Microorganisms

Am J Physiol, 1994 Aug, 267(2 Pt 2), F197 - 207
Cytokines and L-arginine in renal injury and repair; Ketteler M et al.; Advances in molecular biology have identified cytokines as mediators of pathophysiological changes in chronic renal disease . Transforming growth factor-beta (TGF-beta) plays an important role in the pathogenesis of glomerular and interstitial fibrosis, whereas platelet-derived growth factor (PDGF) is involved in proliferative changes in chronic progressive renal diseases . Tumor necrosis factor-alpha and interleukins are expressed in experimental models of renal disease and are causes of inflammation and cell migration . Cytokines act by many different mechanisms, and one target of their action may be L-arginine metabolism . Since the discovery of the effector molecule nitric oxide (NO), generated from L-arginine, knowledge of this pathway has increased dramatically . It became evident that the L-arginine/NO pathway is of major importance in the regulation of hemodynamics and neurotransmission, in host defense against intracellular microorganisms, and in immunologic tissue injury . This pathway is induced by proinflammatory cytokines and possibly regulated by TGF-beta and PDGF . L-Arginine is also metabolized to L-ornithine, which can be processed to polyamines or to L-proline . As polyamines are important mediators of cell growth and L-proline is a substrate for collagen synthesis, both pathways, once activated, may be important in repair processes . It is likely that cytokines and L-arginine metabolism are interconnected and that both are involved in the inflammation, tissue repair, and fibrogenesis processes in the kidney . Dietary protein restriction in progressive renal diseases may substantially affect both systems . This review summarizes current knowledge about interactions of cytokines and L-arginine metabolism and the relevance to renal diseases.

J Allergy Clin Immunol, 1994 Aug, 94(2 Pt 1), 195 - 200
Reduced secretion of IgA to skin surface of patients with atopic dermatitis; Imayama S et al.; To investigate whether the secretory form of immunoglobulin A (sIgA) was reduced on the skin surface in atopic dermatitis, the amount of sIgA present in sweat was measured in 40 patients with atopic dermatitis and in 50 healthy volunteers by attaching a cellulose membrane disk (10 x 10 mm) to the inner aspect of the upper arm skin for 24 hours . The secretory form of IgA, which was absorbed to the membrane and accumulated during the period of application, was revealed as dots by an enzyme immunoassay in which antibodies for IgA and for the secretory component were used . The density and number of dots (per mm2/day), which corresponded to the openings of eccrine excretory ducts, were determined with a densitometer . The mean amount of sIgA secreted by those patients was 3.86 +/- 0.71 pg/mm2/day (range, 0 to 21.17 pg/mm2/day), whereas that of the control subjects was significantly higher (p < 0.001), 16.79 +/- 2.80 pg/mm2/day (range, 0.79 to 133.77 pg/mm2/day) . This may be related to the high incidence of bacterial and viral skin infections seen in patients with atopic dermatitis, and in addition, to the development of eczematous lesions through a defect in ridding the skin of allergens and/or microorganisms.

EMBO J, 1994 Aug 1, 13(15), 3464 - 71
Identification of a high affinity NH4+ transporter from plants; Ninnemann O et al.; Despite the important role of the ammonium ion in metabolism, i.e . as a form of nitrogen that is taken up from the soil by microorganisms and plants, little is known at the molecular level about its transport across biomembranes . Biphasic uptake kinetics have been observed in roots of several plant species . To study such transport processes, a mutant yeast strain that is deficient in two NH4+ uptake systems was used to identify a plant NH4+ transporter . Expression of an Arabidopsis cDNA in the yeast mutant complemented the uptake deficiency . The cDNA AMT1 contains an open reading frame of 501 amino acids and encodes a highly hydrophobic protein with 9-12 putative membrane spanning regions . Direct uptake measurements show that mutant yeast cells expressing the protein are able to take up {14C}methylamine . Methylamine uptake can be efficiently competed by NH4+ but not by K+ . The methylamine uptake is optimal at pH 7 with a Km of 65 microM and a Ki for NH4+ of approximately 10 microM, is energy-dependent and can be inhibited by protonophores . The plant protein is highly related to an NH4+ transporter from yeast (Marini et al., accompanying manuscript) . Sequence homologies to genes of bacterial and animal origin indicate that this type of transporter is conserved over a broad range of organisms . Taken together, the data provide strong evidence that a gene for the plant high affinity NH4+ uptake has been identified.

J Bacteriol, 1994 Aug, 176(16), 5126 - 30
Evidence for structural conservation of Lon and RcsA; Dierksen KP et al.; DNA probes specific to the Escherichia coli genes encoding Lon protease and RcsA hybridized to specific DNA sequences in a number of different microorganisms . Antiserum to either E . coli protein Lon or RcsA reacted with specific proteins in these organisms . These results provide structural evidence of the presence of Lon and RcsA in organisms other than E . coli.

Hepatology, 1994 Aug, 20(2), 356 - 61
Fibrous and obliterative cholangitis in liver allografts: evidence of recurrent primary sclerosing cholangitis?
Harrison RF, Davies MH, Neuberger JM, Hubscher SG.
Fibroobliterative lesions and fibrous cholangitis are characteristic histological lesions of primary sclerosing cholangitis . To determine whether such lesions can be found in the liver allograft, and whether they represent recurrent disease, we reviewed all consecutive histological material taken at greater than 6 mo after transplantation in a 3-yr period from a series of 207 liver transplantations (22 with primary sclerosing cholangitis, 185 controls without primary sclerosing cholangitis) . Because patients with primary sclerosing cholangitis have a biliary system reconstructed by means of a Roux loop, we compared the findings with those from a further control group of patients who had received a Roux loop for reasons other than primary sclerosing cholangitis . Of 22 patients receiving liver transplants for primary sclerosing cholangitis, 7 (32%) patients had biopsy specimens showing features of biliary obstruction, 6 (27%) showed fibrous cholangitis, and 3 (14%) showed classic fibroobliterative lesions . These findings compared with 3 (14%), 1 (5%) and 0 of 22 Roux controls, and 19 (10%), 4 (2%) and 0 of 185 controls without primary sclerosing cholangitis, respectively . The three patients with fibroobliterative lesions either had clinical episodes of cholangitis or had microorganisms in the large bile ducts . However, both biliary obstructive features and fibrous cholangitis were more common in primary sclerosing cholangitis, and fibroobliterative lesions were found only in patients who received transplants for primary sclerosing cholangitis, despite the presence of cholangitis and Roux loops in control patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Immun, 1994 Aug, 62(8), 3311 - 9
High-molecular-mass lipopolysaccharides are involved in Actinobacillus pleuropneumoniae adherence to porcine respiratory tract cells; Paradis SE et al.; Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia . The major adhesin of A . pleuropneumoniae has been identified as the lipopolysaccharides (LPSs) (M . Belanger, D . Dubreuil, J . Harel, C . Girard, and M . Jacques, Infect . Immun . 58:3523-3530, 1990) . Using immunoelectron microscopy and flow cytometry, we showed in the present study that LPSs were well exposed at the surface of this encapsulated microorganism . Immunolocalization with porcine lung and tracheal frozen sections showed that extracted LPS bound to the lung mesenchyme and vascular endothelium and to the tracheal epithelium, respectively . Inhibition of adherence of A . pleuropneumoniae with extracted LPS was also performed with lung and tracheal frozen sections . Acid hydrolysis of LPS revealed that the active component of LPS was not lipid A but the polysaccharides . LPSs from A . pleuropneumoniae serotypes 1 and 2 were separated by chromatography on Sephacryl S-300 SF, in the presence of sodium deoxycholate, according to their molecular masses . The adherence-inhibitory activity was found in the high-molecular-mass fractions . These high-molecular-mass fractions contained 2-keto-3-deoxyoctulosonic acid and neutral sugars, and they were recognized by a monoclonal antibody directed against A . pleuropneumoniae O antigen but not recognized by a monoclonal antibody against capsular antigen.

J Infect Dis, 1994 Aug, 170(2), 464 - 7
Ultrastructural lung pathology of experimental Chlamydia pneumoniae pneumonitis in mice; Yang ZP et al.; The ultrastructural lung pathology of Swiss Webster mice on days 2, 4, 7, 11, 15, and 21 after intranasal inoculation of Chlamydia pneumoniae AR-39 is described . The inflammatory infiltrate was predominantly polymorphonuclear leukocytes on day 2 . By day 7, mononuclear cells were most prominent in the infiltrate . On day 2, chlamydial inclusions were found frequently in the bronchial ciliated epithelial cells and less frequently in the interstitial cells that appeared to be macrophages . Free particles of all developmental forms of the chlamydial microorganism were found in the bronchial lumen and alveolar space . These particles were likely organisms released from infected cells . Inclusions as well as free particles were difficult to find after day 4 . These ultrastructural observations suggest an immunopathologic basis for the acute phase of the disease process.

Neurol Clin, 1994 Aug, 12(3), 541 - 64
Neurologic infections of the fetus and newborn; Griffith BP et al.; This article concentrates primarily on infections of viral origin, although numerous microorganisms can infect the fetal and newborn brain (see Tables 1 and 2) . Intrauterine infections occur most often for HIV, CMV and rubella, whereas HSV is preferentially transmitted intrapartum . In the last decade, changes in the epidemiology of some of the neonatal infections have occurred largely because of the AIDS epidemic . Indeed, pediatric HIV is now the second most frequent viral infection of the newborn (see Table 1) and congenital syphilis has reemerged . Surprisingly, the AIDS epidemic appears to have had minimum impact on infections with other organisms such as Toxoplasma and CMV that commonly infect the brain of adults with AIDS . The recent availability of improved viral diagnostic methods and anti-viral drugs has aided in the identification and treatment of infected newborns.

Biochem Mol Biol Int, 1994 Aug, 33(5), 1023 - 32
How to determine control of growth rate in a chemostat . Using metabolic control analysis to resolve the paradox; Snoep JL et al.; The chemostat makes it possible to study microbial physiology at steady state . However, because growth rate in a chemostat is set by the experimenter, it seems impossible to employ the chemostat to study the control of microbial growth by processes within the microorganism . In this paper we show how, paradoxically, one can determine control of growth rate, of growth yield and of other fluxes in a chemostat . We develop metabolic control analysis for the chemostat . This analysis does not depend on the particular way in which specific growth rate varies with the concentration of the growth limiting substrate.

Am J Infect Control, 1994 Aug, 22(4), 218 - 23
Use of image analysis to measure handwashing effectiveness; Turner JG et al.; BACKGROUND: This study tested a unique quantification technology (image analysis of fluorescent particles) for the measurement of handwashing effectiveness, comparing an automated system with traditional manual handwashing . In this instance, handwashing "effectiveness" was defined as ability of the technique to remove surface soil, as opposed to removal of microorganisms . METHODS: Sixty-five subjects washed their hands by manual handwashing (day 1) and automated handwashing (day 2) . Hands were coated with an oil-based fluorescent suspension, photographed under controlled conditions, washed for 10 seconds, and rephotographed . Photographs from before and after handwashing were subjected to image analysis . RESULTS: Manual handwashing removed 73.1% of the particles; the automated method removed 23.2% . Parameters for use of image analysis as a technique to examine removal of gross contamination from the hands are given in the text . CONCLUSIONS: Although this method will not replace traditional culture methods for examining microbial removal, it is useful for measuring removal of particles (gross contamination) from skin or other surfaces . Under the conditions tested, manual handwashing was found to be decidedly superior to use of an automated system for removal of oil-based soil on the hands.

J Rheumatol, 1994 Aug, 21(8), 1573 - 7
Piroxicam induced pulmonary infiltrates and eosinophilia; Pfitzenmeyer P et al.; We describe 2 patients who developed pulmonary infiltrates while being treated with piroxicam . There was no satisfactory explanation other than drug induced lung disease for their illness . They had no exposure to pneumotoxic drugs or aerocontaminants . Microorganisms were not cultured in sputum or bronchoaveolar lavage . There was no underlying illness with possible lung involvement . Pulmonary infiltrates developed during piroxicam therapy, disappeared after drug withdrawal and recurred following rechallenge.

Histochem J, 1994 Aug, 26(8), 666 - 77
Histochemical analysis of glycoproteins in the unicellar glands in the epidermis of an Indian freshwater fish Mastacembelus pancalus (Hamilton); Mittal AK et al.; The unicellular glands in the epidermis of the Indian freshwater fish Mastacembelus pancalus consist of three types of mucous cells and sacciform cells . The histochemical properties of their secretory glycoproteins have been analysed by means of a battery of histochemical methods . These included methods for the identification and simultaneous visualization of oxidizable vicinal diols, O-acyl sugars, O-sulphate esters and sialic acid residues with or without side-chain O-acyl variants . Four general classes of glycoproteins (GPs) were identified . These included (i) GPs with O-sulphate esters and oxidizable vicinal diols, (ii) GPs with oxidizable vicinal diols and sialic acid residues with or without O-acyl substitution at C7, (iii) GPs mainly with O-sulphate esters, low moieties of GPs with oxidizable vicinal diols, O-acyl sugars and sialic acid residues with side-chain O-acyl variant predominantly at C8 (or which are di- or tri-substituted) or C9 and in traces of sialic acid residues without O-acyl substitution or with O-acyl substitution at C7, and (iv) GPs with traces of oxidizable vicinal diols, O-acyl sugars and sialic acid residues with O-acyl substitution at C8 (or which are di- or tri-substituted) or C9 . The physiological significances of these GP classes and their release on the surface of the epidermis are discussed with special reference to their role in lubrication, protection and inhibition of the invasion and proliferation of pathogenic microorganisms in the epidermis, as adapted to the peculiar mode of life of the fish.

Anal Biochem, 1994 Aug 1, 220(2), 244 - 8
Estimation of the sulfate content of hydrothermal vent bacterial polysaccharides by Fourier transform infrared spectroscopy; Lijour Y et al.; Deep-sea hydrothermal vents are characterized by unusual chemical and physical parameters, including high pressure and temperature . In this extreme environment, unusual microorganisms of biotechnological importance survive . Polymer-producing bacteria have been specifically studied for several years with the aim of demonstrating their ability to produce unusual polysaccharides in terms of physical, chemical, and biological properties . Because sulfates play an important role in the biological properties of polysaccharides, it is very important to determine their content with accuracy . Fourier transform infrared spectroscopy (FT-IR) was used for sulfate analysis and the results were compared with those of other analytical techniques . We found a good correlation between FT-IR and other analytical techniques for sulfate concentrations ranging from 2.4 to 20% . The data indicated that this technique could be used to determine the chemical composition of the polymers along with a semiquantitative estimation of the sulfate content.

J Periodontol, 1994 Aug, 65(8), 755 - 61
A preliminary report on a method for studying the permeability of expanded polytetrafluoroethylene membrane to bacteria in vitro: a scanning electron microscopic and histological study; Simion M et al.; The technique of guided tissue regeneration using expanded polytetrafluoroethylene (ePTFE) membranes has been shown to be effective in implant dentistry (bony defects, extremely thin alveolar ridges, and implants placed in fresh extraction sockets) . One of the drawbacks associated with the use of membranes is their premature exposure with consequent bacterial contamination . The aim of this study was to examine the possibility that oral bacteria migrate through the occlusive portion of ePTFE membranes and to determine the time needed for microorganisms to pass from the outer surface to the inner surface of the membranes . A removable acrylic device was adapted to the molar-premolar region of one quadrant of the jaws in each of three volunteers . Five cylindrical teflon chambers were glued to the buccal aspect of each device . The chambers were divided into two rooms separated by the inner portion of a ePTFE membrane . The outer room was open to the oral cavity allowing plaque accumulation; the inner room was isolated from the oral cavity by the ePTFE membrane . One of the 5 chambers was completely closed and used as control . The test period lasted for 4 weeks . Every week, one chamber was removed from each device and processed for scanning electron microscopic and histologic examinations . Our study showed the possibility that oral bacteria may contaminate ePTFE membranes exposed to the oral cavity . One specimen showed partial bacterial penetration after 2 and 3 weeks, but after 4 weeks, all membrane specimens demonstrated bacterial contamination.(ABSTRACT TRUNCATED AT 250 WORDS)

J Am Coll Nutr, 1994 Aug, 13(4), 311 - 3
Review: microbiology of the gastrostomy tube; Gottlieb K et al.; This review summarizes what is presently known about microbial colonization of silicone gastrostomy feeding tubes and their deterioration . Feeding tubes are frequently colonized by fungal and bacterial organisms . Candida organisms seem to originate from the oral cavity from where they colonize the stomach and the gastrostomy tubes . It appears that many microorganisms are able to metabolize certain polymer additives, and although this is well described for polyvinyl chloride, it is not for silicone elastomers . However, clinical evidence for a role of microorganisms in the deterioration of silicone feeding tubes is very strong . The clinical significance of gastrointestinal tract seeding from gastrostomy tubes, which act as incubators, is not fully understood and deserves further study . Likewise, deterioration of feeding tubes must be investigated systematically to address the safety and economical issues it presents.

Cytopathology, 1994 Aug, 5(4), 243 - 50
Actinomycosis in fine needle aspiration cytology; Das DK; Four cases of actinomycosis were diagnosed by fine needle aspiration (FNA) cytology and eight more cases were detected during a review of FNA smears reported as inflammatory . The age of these 12 cases ranged from 20 to 61 years with a median of 35 years . The male to female ratio was 3:1 . The common regions of involvement were cervicofacial in seven cases (58.3%), thoracic in three (25.0%) and abdominal in two (16.7%) . Four of the seven cervicofacial cases presented with intra-oral masses; the thoracic lesions were pulmonary in location, and the abdominal lesions presented as bowel masses . The possibility of actinomycosis was not considered clinically in any case . The main reason for missed cytodiagnosis in two thirds of the cases appeared to be observer error . It is suggested that when the aspiration smear from a mass is found to be an inflammatory exudate rich in neutrophils, special efforts must be made to look for this microorganism.

Curr Opin Immunol, 1994 Aug, 6(4), 590 - 5
Interactions of bacteria with non-phagocytic cells; Galan JE; It is becoming increasingly clear that bacterial pathogens can manipulate the host cell to their advantage . Recently, we have learnt more about the different strategies that microorganisms have evolved to subvert normal host-cellular functions . These strategies allow bacteria to gain access to, survive, and replicate within host cells, as well as to spread to neighboring cells, without the need for an extracellular phase . During the next few years, we expect to learn much more about these mechanisms and, in the process, it is likely that we will learn more about the host itself.

Nippon Rinsho, 1994 Aug, 52(8), 1977 - 81
{Pathways leading to intractable vasculitis syndromes: a review}; Ishikura H et al.; Intractable vasculitis syndromes are reviewed in terms of pathways leading to the diseases . The III-type, IV-type, and II-type allergic reaction, as well as angiospasm and endothelial dysfunction pathways are important in the pathogenesis of vasculitis . Each pathway has been described, using appropriate animal models or experimental and clinical data . Antigens of microorganisms are, among others, important pathogenic factors, activating several pathways . Endogenous retroviral antigens in the mouse, and possibly in humans, cause vasculitis through the II-type and III-type hypersensitivity, and experiments on the intractable vasculitis remain to be focused on this point.

FEMS Microbiol Rev, 1994 Aug, 14(4), 339 - 49
Microbial oxidation and reduction of manganese: consequences in groundwater and applications; Gounot AM; In the natural environment, manganese is found as reduced soluble or adsorbed Mn(II) and insoluble Mn(III) and Mn(IV) oxides . Mn oxidation has been reported in various microorganisms . Several possible pathways, indirect or direct, have been proposed . A wider variety of Mn-reducing microorganisms, from highly aerobic to strictly anaerobic, has been described . The mechanisms of Mn reduction can be either an indirect process resulting from interactions with organic or inorganic compounds, or a direct enzymatic (electron-transfer) reaction . The role of microorganisms in Mn cycle is now well demonstrated by various methods in superficial natural environments, and research has been initiated on subsurface sediments . Observations in vivo (Rhone valley) and under in vitro suggested that bacterial activities are the main processes that promote manganese evolution and migration in shallow aquifers . After the building of hydroelectric dams, the stream of the Rhone was modified, giving rise to mud deposition on the bank . In the mud, bacteria are stimulated by the high organic content and consume oxygen . The redox potential drops . The manganese oxides previously formed under aerobic conditions are reduced and soluble manganese (Mn(II)) migrates into the aquifer . If the subsurface sediments are coarse-grained, the aquifer is well aerated, allowing the re-oxidation of Mn(II) by the oligotrophic attached bacteria in aquifer sediments . If the aquifer is confined, aeration is not sufficient for Mn-reoxidation . Mn(II) remains in a reduced state and migrates to the wells . Furthermore, the presence of organic matter in subsurface sediments results in the reduction of previously formed Mn oxides . Pseudo-amorphous manganese oxides, which were probably recently formed by bacteria, are more readily reduced than old crystalline manganese oxides . Although the concentrations of soluble manganese found in groundwaters are not toxic, it still is a problem since its oxidation results in darkening of water and plugging of pipes in drinking or industrial water systems . Soluble manganese can be removed from water by biological processes involving manganese-oxidizing bacteria, either in situ, or in sand filters after pumping . Various procedures are mentioned.

Glycoconj J, 1994 Aug, 11(4), 304 - 8
Complement-dependent cytotoxic activity of serum mannan-binding protein towards mammalian cells with surface-exposed high-mannose type glycans; Ohta M et al.; Serum mannan-binding protein (S-MBP), a lectin specific for mannose and N-acetylglucosamine, activates complement through the classical pathway . With the help of complement, S-MBP lyses red blood cells which have been coated with yeast mannan and kills bacteria which have N-acetylglucosamine and/or L-glycero-D-manno-heptose on their core oligosaccharide . In this study, we examined whether mammalian cells, on which S-MBP could bound, are killed by a complement-dependent mechanism . When baby hamster kidney (BHK) cells were treated with an alpha-mannosidase inhibitor, 1-deoxymannojirimycin (dMM), most of the cellular oligosaccharides were transformed from the complex-type to the high mannose-type . S-MBP bound to the dMM-treated BHK cells in the presence of Ca2+, and this binding was eliminated by mannose . When dMM-treated cells, labelled with 51Cr, were incubated with complement, radioactivity was released in a dose-dependent manner by S-MBP and complement . This release was not observed with heat-inactivated complement . These observations suggest that S-MBP is able, with the help of complement, to kill not only exogenous microorganisms but also mammalian cells which have high mannose-type oligosaccharides exposed on their surfaces.

Electrophoresis, 1994 Aug-Sep, 15(8-9), 1051 - 61
Analysis of photoreceptor proteins of microorganisms by gradient gel electrophoresis and other biochemical separation methods; Hader DP et al.; Photoreceptor proteins for photoorientation in microorganisms are usually membrane bound and can be isolated by standard biochemical methods . Three examples are shown: the flagellates Euglena gracilis, Peridinum gatunense and the slime mold Dictyostelium discoideum . The photoreceptor of Euglena is attached to the basis of the flagellum and is composed of at least four chromoproteins which can be separated by gradient sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) fast protein liquid chromatography (FPLC) and isoelectric focusing (IEF); it contains pterins and a flavin as chromophoric groups . The photoreceptor of Peridinium absorbs in the red wavelength band . Though not yet identified in detail, multiple receptors are probably involved, as indicated by fluorescence spectroscopy . Dictyostelium shows positive and negative phototaxis in its amoebal form and exclusively positive phototaxis in its pseudoplasmodial form . It is still open to discussion whether the two stages use separate photoreceptors . From amoebae two photoreceptor pigments have been isolated, showing an absorption which resembles the action spectrum, one membrane bound with a molecular mass of 45 kDa and one cytoplasmic fraction with a molecular mass of 27 kDa.

Zh Mikrobiol Epidemiol Immunobiol, 1994 Aug-Sep, Suppl 1, 99 - 103
{The effect of the characteristics of the interaction of their determinant of virulence with the metabolic and specific mechanisms of immunity on the persistence of infectious causative agents}; Adamov AK; The persistence of the causative agents of infections depends on the effectiveness of the function of their virulence determinants ensuring their nutrition in the host body and resistance to its nonspecific and specific mechanisms of protection . The presence of antigens, effective mechanisms of antigenic reconstruction and, probably, the optimum ratio of strong and weak antigens in pathogenic microorganisms facilitates their persistence in the body of an immune host.

Glycobiology, 1994 Aug, 4(4), 469 - 75
Purification and immunohistochemistry of Griffonia simplicifolia agglutinin-II-binding mucus glycoprotein in rat stomach; Oinuma T et al.; Gastric mucus is thought to protect the gastric wall from mechanical trauma, desiccation, pathogenic microorganisms, acid and proteases . We purified Griffonia simplicifolia agglutinin-II (GSA-II)-binding mucus glycoprotein (GMG) from rat gastric mucosa by solubilization in a guanidine-containing buffer, gel permeation chromatography, Ricinus communis agglutinin-I (RCA-I)-affinity chromatography and GSA-II-affinity chromatography . Rat GMG showed high molecular weight on a Sephacryl S-1000 column, and a single band in 0.5% agarose-2% polyacrylamide composite gels and blots . A protein of approximately 60 kDa was contained in the GMG preparation . GMG was deglycosylated with trifluoromethanesulphonic acid treatment . An antibody was raised against deglycosylated GMG (deGMG) . The antibody recognized deGMG, GMG, periodic acid-treated deGMG and O-glycanase-digested deGMG, but did not react to trypsin-digested deGMG . These results suggest that the antibody recognizes proteinase-sensitive region or peptide backbone of GMG . In immunohistochemistry, the mucous gel layer of the stomach luminal surface was stained with antibody . The antibody recognized not only gastric mucous neck cells and pyloric gland cells, but also gastric surface mucous cells, mucous cells in the duodenal gland, and goblet cells in the small intestine and colon . These results indicate that GMG is a component of rat gastric mucus, and that the antibody recognizes mucous-secreting cells in rat stomach and intestine.

Eur J Clin Microbiol Infect Dis, 1994 Aug, 13(8), 658 - 9
Guillain-Barré syndrome associated with acute Q fever; Bernard E et al.; Several bacterial and viral agents have been implicated in the pathogenesis of the Guillain-Barre syndrome, an acquired immune-mediated disorder . A case of Guillain-Barre syndrome associated with acute Q fever is described . Coxiella burnetii should therefore be added to the list of microorganisms capable of inducing the Guillain-Barre syndrome.

Eur J Obstet Gynecol Reprod Biol, 1994 Aug, 56(2), 95 - 101
Prevalence and influence of Mycoplasma hominis and Ureaplasma urealyticum in 218 African pregnant women and their infants; Luton D et al.; OBJECTIVES: To estimate the prevalence of Ureaplasma urealyticum (Uu) and Mycoplasma hominis (Mh) in the lower genital tract of pregnant women, their evolution during pregnancy, and the effect of these pathogens on the outcome of pregnancy in Equatorial Africa . STUDY DESIGN: 218 pregnant women were followed from before 20 weeks gestational age through delivery . Samples were taken from the cervix at every visit and from the newborn at delivery and tested for Uu and Mh . The data were analysed using Student's t-test, the Mann-Whitney, or the chi 2-test . RESULTS: The prevalence of cervical colonization by Ureaplasma urealyticum and Mycoplasma hominis in pregnant women was 79% and 41% respectively . Colonization with Uu and Mh increased significantly throughout pregnancy (P < 0.001) . Their presence was associated with lower gestational age at delivery, lower birth weight and increased neonatal morbidity and mortality (P < 0.05) . Erythromycin therapy did not have any effect on the evolution of Uu and Mh colonization during pregnancy . CONCLUSION: Uu and Mh are additional factors that might contribute to poor pregnancy outcome in a country where neonatal health is already impaired by many other microorganism.

FEMS Immunol Med Microbiol, 1994 Aug, 9(2), 91 - 100
The role of infectious agents in sudden infant death syndrome; Blackwell CC et al.; Epidemiological factors associated with susceptibility to respiratory infections are similar to those associated with Sudden Infant Death Syndrome . Here we review the evidence that respiratory pathogens might be involved in some cases of Sudden Infant Death Syndrome in the context of factors identified in epidemiological studies of cot deaths: the age range affected; mother' smoking; respiratory viral infections; immunisation status . Both laboratory and epidemiological evidence suggests that vulnerability of infants to infectious agents depends on interactions between genetic, developmental and environmental factors that contribute to colonisation by microorganisms, the inflammatory and specific immune responses and the infants' physiological responses to inflammatory mediators . A model is proposed to explain how microorganisms might trigger a series of events resulting in some of these unexpected deaths and discusses how the the present recommendations regarding child care practices might help reduce the numbers of Sudden Infant Death Syndrome cases associated with infectious agents.

J Cutan Pathol, 1994 Aug, 21(4), 289 - 96
Idiopathic plantar hidradenitis: a neutrophilic eccrine hidradenitis occurring primarily in children; Stahr BJ et al.; Neutrophilic eccrine hidradenitis (NEH) has been described in a variety of clinical settings but is most often seen in leukemic patients receiving chemotherapy . We have recently encountered 6 healthy individuals, of whom 5 were children, who developed NEH localized to the feet . The patients were from 9 to 21 years of age . The presenting complaint was rapid development of tenderness of the feet with varying degrees of morbidity . At clinical evaluation, tender, erythematous papules and nodules were confined to the feet, primarily the plantar surfaces . The major differential diagnoses were erythema nodosum and vasculitis . Laboratory studies were non-contributory . Histologically, the findings were generally similar to those of NEH with certain exceptions, most notably the absence of syringosquamous metaplasia and the presence, in most cases, of neutrophilic abscesses in eccrine coils . Inflammatory and degenerative changes involved primarily the eccrine duct (coiled and dermal), and tended to spare the secretory apparatus . Stains for microorganisms were negative . There were brief recurrences in some of the patients, but those followed over time have remained well . We suggest the term idiopathic plantar hidradenitis for this condition.

Biosci Biotechnol Biochem, 1994 Aug, 58(8), 1545 - 6
Isolation and characterization of a dipeptidyl aminopeptidase from Streptomyces sp . WM-23; Murao S et al.; A screening test was undertaken to isolate microorganisms that produced dipeptidyl aminopeptidase . The hydrolytic activity toward alanyl-phenylalanine p-nitroanilide was found in a culture filtrate of a actinomyces strain (WM-23), newly isolated from a soil sample . The enzyme (WM-23 dipeptidyl aminopeptidase) was isolated from the culture filtrate as a homogeneous preparation . The WM-23 enzyme, inhibited by phenylmethylsulfonyl fluoride, may be classified to mammalian dipeptidyl aminopeptidase II . The enzymatic characteristics were investigated.

J Leukoc Biol, 1994 Aug, 56(2), 166 - 73
Functional characterization of peripheral circulating and liver recruited neutrophils in endotoxic rats; Spitzer JA et al.; Neutrophil accumulation in tissue is a hallmark of inflammation and is associated with a variety of pathological conditions . In bacterial infection neutrophils are selectively attracted in large numbers to phagocytose and kill invading microorganisms . However, activated neutrophils can also cause injury to tissues . To investigate functional alterations in liver recruited neutrophils (PMNs), we studied the functional characteristics of circulating blood and liver sequestered PMNs in terms of host defense mechanisms, such as nitric oxide (NO) and superoxide (SO) generation, beta 2 integrin expression, phagocytosis, and eicosanoid profile . Cells were isolated from rats infused with a nonlethal dose (320 micrograms/kg) of E . coli endotoxin (ET) or pyrogen-free saline for 90 min . Liver PMNs produced significantly more NO both in the absence and in the presence of an in vitro endotoxin challenge than did blood PMNs . No significant difference was observed in phorbol myristate acetate-stimulated SO generation . Endotoxin infusion significantly up-regulated the expression of CD11b/c in circulating and even more so in liver PMNs . Phagocytosis was significantly enhanced by in vivo ET treatment in blood PMNs, and liver PMNs showed even greater phagocytic activity than blood PMNs or Kupffer cells . The percent distribution of prostaglandins D2 and E2 of total 14C-eicosanoids was significantly higher and that of thromboxane B2 and 5-, 12-, and 15-HETEs was significantly lower in liver than in blood PMNs . Our study demonstrates several functional differences between liver-recruited and circulating PMNs in an acute endotoxic model . The implications of altered neutrophil function may extend to mechanisms of host defense and hepatotoxicity associated with sepsis and endotoxemia.

Am J Obstet Gynecol, 1994 Aug, 171(2), 455 - 60
Proliferative response to conserved epitopes of the Chlamydia trachomatis and human 60-kilodalton heat-shock proteins by lymphocytes from women with salpingitis; Witkin SS et al.; OBJECTIVE: Our objective was to determine whether an upper genital tract Chlamydia trachomatis infection sensitizes lymphocytes to heat-shock protein epitopes expressed in both the human and chlamydial 60 kd heat-shock protein . STUDY DESIGN: Peripheral blood mononuclear cells were isolated from women with or without a prior documented salpingitis and tested for their ability to proliferate in response to the recombinant C . trachomatis heat-shock protein and to five synthetic peptides corresponding to conserved epitopes expressed in both the human and chlamydial heat-shock proteins . RESULTS: Among 22 healthy women with no history of chlamydial infections or salpingitis and 10 women seen for complaints other than a C . trachomatis infection, none had positive lymphocyte responses to any of the peptides and only one responded to the chlamydial heat-shock protein . Among nine women with a single episode of salpingitis none responded to the chlamydial heat-shock protein and one exhibited a positive lymphocyte response to a single peptide . This woman was also positive for C . trachomatis in the cervix . In contrast, among the 10 women with two or more episodes of salpingitis four (40%) had proliferation in response to the chlamydial heat-shock protein and five (50%) had positive lymphocyte responses to one of the peptides; two of these women also had C . trachomatis detected in their cervices . CONCLUSION: In women with a history of C . trachomatis upper genital tract infections, infection with C . trachomatis or other microorganisms can induce a lymphocyte proliferative response to the chlamydial 60 kd heat-shock protein and to epitopes present in the human heat-shock protein.

Leukemia, 1994 Aug, 8(8), 1424 - 34
Effective treatment of mycoplasma contamination in cell lines with enrofloxacin (Baytril); Fleckenstein E et al.; Continuous cell lines are frequently contaminated with microorganisms, mycoplasmas being the most prominent and cumbersome . In our experience, of the 300 cell lines examined more than one third was infected with mycoplasmas . Mycoplasma contamination can affect virtually every parameter and functional activity of a cultured cell . An alternative to the recommended disposal of infected cultures is an attempt to eliminate the contaminants . Adding antibiotics with strong activity against mycoplasmas to the culture medium is a simple, inexpensive and efficient decontamination method . Here, we studied the effectiveness of the new antibiotic enrofloxacin (Baytril) developed specifically for use against mycoplasmas . Baytril is a new synthetic agent from the group of quinolone derivatives that are DNA gyrase inhibitors . Thirty-two chronically infected cell lines (27 human leukemia-lymphoma cell lines) were treated with Baytril in a prospective study in direct comparison with three other well-established anti-mycoplasma regimens, the antibiotics BM-Cyclin, Ciprobay and MRA (Mycoplasma Removal Agent) . Mycoplasmas were detected by DNA staining, agar colony growth, DNA-RNA hybridization, polymerase chain reaction, and monoclonal antibody staining . Treatment with Baytril eliminated the contaminants in 30/32 cultures (94%) . The cure rates for Ciprobay, BM-Cyclin and MRA were 91%, 81%, and 75%, respectively . The IC50 values of Baytril for cell lines varied over a wide range depending on the type of hematopoietic cell lineage with T- and B-cell lines being more sensitive targets . Baytril-treated cell lines remained mycoplasma-negative over a 12-week antibiotic-free culture period . Low levels of mycoplasma infection were shown not to persist by repeat testing after growth without antibiotics . A retrospective analysis of anti-mycoplasma treatments with BM-Cyclin, Ciprobay, MRA or Baytril showed that 265/351 cultures (75%) were immediately cured of mycoplasma; however, all of the remaining, mycoplasma-positive cultures harboring mycoplasms resistant to the first antibiotic could be cleaned up by a second round with a different antibiotic . Baytril is an efficient anti-mycoplasma antibiotic and based on its high cure rate might be the treatment of first choice.

Schweiz Med Wochenschr, 1994 Jul 30, 124(30), 1326 - 33
{Heart and AIDS}; Buhler JA et al.; Although pulmonary and central nervous symptoms prevail before death, autopsy often reveals marked myocardial alterations in AIDS patients . This discrepancy prompted us to systematically study cardiac alterations in 100 sequential autopsies of patients who died of AIDS . We appraised the results in relation to changes noted in other organ systems, and compared our data with the AIDS-associated cardiac alterations described in the literature . Cardiac lesions were present in more than 50% of our patients, predominantly in the myocardium (47%) . 38 patients displayed signs of active myocarditis . The endocardium and epicardium were secondarily involved, although drug abuse (23 patients) was the most important risk factor for HIV infection, after homosexuality (44%) . The prevailing opportunistic agents were identical to those generally seen in AIDS patients, i.e . toxoplasma, cytomegalovirus, mycobacteria and fungi, with the exception of Pneumocystis carinii . This microorganism spared the heart, although it was present in the lungs of 47 patients . Our results are in keeping with other published data . Toxoplasma, present in the myocardium of our patients more frequently than reported in other series, did not necessarily cause a concomitant myocarditis; Coxsackie viruses are deemed to be responsible for many cases of myocarditis in AIDS patients, perhaps even in cases in which we found toxoplasma pseudocysts to be present in the heart muscle . The study clearly shows that the heart is often the unrecognized target of AIDS-associated lesions, even in the initial phase of the AIDS outbreak (1981-1989) . Thus, not every shortness of breath is necessarily of pulmonary origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Philos Trans R Soc Lond B Biol Sci, 1994 Jul 29, 345(1311), 65 - 73
Theoretical and practical aspects of the quantification of biodiversity among microorganisms; O'Donnell AG et al.; The quantification of biodiversity among microorganisms has to address both theoretical and practical aspects . Species concepts are often at variance with those applied in macroorganisms, and satisfactory concepts suitable for general use in bacteria and fungi have yet to be formulated . Molecular approaches have not yet provided a universal solution to this key issue . Quantification in habitats such as soil is difficult as isolation procedures yield only a small and skewed selection of the microorganisms present . Indices of taxonomic or phylogenetic diversity have potential in the quantification of microbial diversity at a range of ranks, but the non-equivalence of ranks and representatives of the taxa detected have to be addressed . Chemical and molecular methods have immense potential in the quantification of microbial diversity in environmental samples; 16S rRNA has shown particular promise with bacteria, but as yet the fungi lack a universal probe . A greater awareness of the limitations of existing approaches and methodologies used by microbiologists is needed, but significant progress can be anticipated as new technologies are developed and become more widely adopted.

Philos Trans R Soc Lond B Biol Sci, 1994 Jul 29, 345(1311), 21 - 33
Biodiversity at the molecular level: the domains, kingdoms and phyla of life; Embley TM et al.; The results of comparative sequence analysis, mainly of small subunit (SSU) ribosomal (r)RNA sequences, have suggested that all of cellular life can be placed in one of three domains: the Archaea, Bacteria or Eucarya . There is some evidence that the Archaea may not be a monophyletic assemblage, but as yet this issue has not been resolved . Most of the lineages, and all of the deepest ones, in the tree based upon SSU rRNA sequences, are microbial . Traditional ideas of classification such as Whittaker's five kingdom scheme do not adequately describe life's diversity as revealed by sequence comparisons . There are many microbial groups that demonstrate much greater amounts of SSU rRNA sequence divergence than do members of the classical kingdoms, Animalia, Plantae and Fungi . The old microbial kingdoms Monera and Protista are clearly paraphyletic but as yet there is no consensus as to how they should be reorganized in taxonomic terms . New data from environmental analysis suggests that much of the microbial world is unknown . Every environment which has been analysed by molecular methods has revealed many previously unrecorded lineages . Some of these show great divergence from the sequences of cultured microorganisms suggesting that fundamentally new microbial groups remain to be isolated . The relationships of some of these new lineages may be expected to affect how the tree of life is organized into higher taxa, and to also influence which features will be recognized as synapomorphies . There is currently no objective measure whereby microbial diversity can be quantified and compared to the figures which are widely quoted for arthropods and other Metazoa.

Philos Trans R Soc Lond B Biol Sci, 1994 Jul 29, 345(1311), 101 - 18
Estimating terrestrial biodiversity through extrapolation; Colwell RK et al.; Both the magnitude and the urgency of the task of assessing global biodiversity require that we make the most of what we know through the use of estimation and extrapolation . Likewise, future biodiversity inventories need to be designed around the use of effective sampling and estimation procedures, especially for 'hyperdiverse' groups of terrestrial organisms, such as arthropods, nematodes, fungi, and microorganisms . The challenge of estimating patterns of species richness from samples can be separated into (i) the problem of estimating local species richness, and (ii) the problem of estimating the distinctness, or complementarity, of species assemblages . These concepts apply on a wide range of spatial, temporal, and functional scales . Local richness can be estimated by extrapolating species accumulation curves, fitting parametric distributions of relative abundance, or using non-parametric techniques based on the distribution of individuals among species or of species among samples . We present several of these methods and examine their effectiveness for an example data set . We present a simple measure of complementarity, with some biogeographic examples, and outline the difficult problem of estimating complementarity from samples . Finally, we discuss the importance of using 'reference' sites (or sub-sites) to assess the true richness and composition of species assemblages, to measure ecologically significant ratios between unrelated taxa, to measure taxon/sub-taxon (hierarchical) ratios, and to 'calibrate' standardized sampling methods . This information can then be applied to the rapid, approximate assessment of species richness and faunal or floral composition at 'comparative' sites.

Gene, 1994 Jul 22, 145(1), 97 - 101
Sequencing and expression of the aroA gene from Dichelobacter nodosus; Alm RA et al.; The aroA locus of the Gram- pathogen Dichelobacter nodosus, which encodes 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase, has been sequenced and expressed in Escherichia coli . The gene is located on a 1.48-kb DraI-HindIII fragment located directly upstream and in opposite transcriptional orientation to the gene encoding the fimbrial structural subunit . The deduced open reading frame is 1329 nucleotides in length, which encodes a protein of 443 amino acids (aa) with a calculated M(r) of 47,413, which was visualized in E . coli minicells, under the control of its native promoter . This derived aa sequence displays significant similarities with the sequences of the aroA gene products from a variety of microorganisms.

Science, 1994 Jul 22, 265(5171), 524 - 8
The three-dimensional crystal structure of the catalytic core of cellobiohydrolase I from Trichoderma reesei; Divne C et al.; Cellulose is the major polysaccharide of plants where it plays a predominantly structural role . A variety of highly specialized microorganisms have evolved to produce enzymes that either synergistically or in complexes can carry out the complete hydrolysis of cellulose . The structure of the major cellobiohydrolase, CBHI, of the potent cellulolytic fungus Trichoderma reesei has been determined and refined to 1.8 angstrom resolution . The molecule contains a 40 angstrom long active site tunnel that may account for many of the previously poorly understood macroscopic properties of the enzyme and its interaction with solid cellulose . The active site residues were identified by solving the structure of the enzyme complexed with an oligosaccharide, o-iodobenzyl-1-thio-beta-cellobioside . The three-dimensional structure is very similar to a family of bacterial beta-glucanases with the main-chain topology of the plant legume lectins.

Mikrobiol Z, 1994 Jul-Sep, 56(4), 36 - 42
{The biological properties of Aerococcus antagonists, representatives of human microbiocenoses}; Kremenchutskii GN et al.; The paper deals with the data on biology of Aerococcus, a slightly studied group of microorganisms . Physiological-biochemical properties of Aerococcus are described, data of their distribution in nature are given . Peculiar attention is paid to the estimate of the role of Aerococcus in human microbiocenoses . As a result of the profound and all-round study of this group of microorganisms the authors have developed new bacterial drug "A-bakterin" based on the aerococcus strain . Data presented about the results of clinical tests of "A-bakterin" are presented, a possibility to use Aerococcus lysate in the elaboration of new drugs is discussed.

FEMS Microbiol Lett, 1994 Jul 1, 120(1-2), 11 - 2
Further evidence in support of the authenticity of microorganisms believed to have survived for 5300 years; Haselwandter K et al.; It has been questioned whether the microorganisms isolated from hay, which the ice-man had used for padding his boots, were authentic . The arguments in favour of, and those brought forward against, the authenticity are discussed . Based upon additional circumstantial evidence we maintain our view that the microbial strains isolated from the grass samples are more likely to be of ancient origin than to have been derived from secondary contamination.

Trends Microbiol, 1994 Jul, 2(7), 250 - 4
Infection and multiple sclerosis: a possible role for superantigens?
Brocke S, Veromaa T, Weissman IL, Gijbels K, Steinman L.
The association of infection with autoimmune diseases is enigmatic, partly because cause and effect are difficult to establish in chronic diseases . Microorganisms might initiate multiple sclerosis and trigger relapses of disease . Superantigens might be involved in autoimmunity through the (re)activation of T cells, including autoreactive cells, expressing certain T cell receptor beta chain variable regions.

Appl Environ Microbiol, 1994 Jul, 60(7), 2438 - 49
Evidence for a novel pathway in the degradation of fluorene by Pseudomonas sp . strain F274; Grifoll M et al.; A fluorene-utilizing microorganism, identified as a species of Pseudomonas, was isolated from soil severely contaminated from creosote use and was shown to accumulate six major metabolites from fluorene in washed-cell incubations . Five of these products were identified as 9-fluorenol, 9-fluorenone, (+)-1,1a-dihydroxy-1-hydro-9-fluorenone, 8-hydroxy-3,4-benzocoumarin, and phthalic acid . This last compound was also identified in growing cultures supported by fluorene . Fluorene assimilation into cell biomass was estimated to be approximately 50% . The structures of accumulated products indicate that a previously undescribed pathway of fluorene catabolism is employed by Pseudomonas sp . strain F274 . This pathway involves oxygenation of fluorene at C-9 to give 9-fluorenol, which is then dehydrogenated to the corresponding ketone, 9-fluorenone . Dioxygenase attack on 9-fluorenone adjacent to the carbonyl group gives an angular diol, 1,1a-dihydroxy-1-hydro-9-fluorenone . Identification of 8-hydroxy-3,4-benzocoumarin and phthalic acid suggests that the five-membered ring of the angular diol is opened first and that the resulting 2'-carboxy derivative of 2,3-dihydroxy-biphenyl is catabolized by reactions analogous to those of biphenyl degradation, leading to the formation of phthalic acid . Cell extracts of fluorene-grown cells possessed high levels of an enzyme characteristic of phthalate catabolism, 4,5-dihydroxyphthalate decarboxylase, together with protocatechuate 4,5-dioxygenase . On the basis of these findings, a pathway of fluorene degradation is proposed to account for its conversion to intermediary metabolites . A range of compounds with structures similar to that of fluorene was acted on by fluorene-grown cells to give products consistent with the initial reactions proposed.

Ther Umsch, 1994 Jul, 51(7), 459 - 61
{History of vitamins}; Muller-Landgraf I; The history of the discovery of vitamins was initiated by the observation that beriberi is caused by qualitatively poor nutrition rather than by microorganisms . An early theory suggested the formation of toxins by improper cooking, preservation, or storage; however, research soon took another turn . Feeding experiments with standardized food pointed at the existence of 'accessory factors', present in food in small amounts . These factors seemed to be essential for the maintenance of metabolic processes, yet could not be synthesized by the organism . This was the initial spark for a worldwide research boom . The period from 1912 to 1948 saw the isolation and identification of individual factors belonging to a variety of chemical classes collectively labeled as 'vitamins'.

J Leukoc Biol, 1994 Jul, 56(1), 36 - 40
Selective Mycobacterium avium-induced production of nitric oxide by human monocyte-derived macrophages; Dumarey CH et al.; Infection with a virulent strain of Mycobacterium avium, but not with virulent Mycobacterium tuberculosis or avirulent Mycobacterium smegmatis, induced the formation of nitric oxide by human monocyte-derived macrophages . This process was not affected by lipopolysaccharide or cytokines such as interferon-gamma or tumor necrosis factor alpha . M . avium-induced nitric oxide production was significantly decreased by NG-monomethyl-L-arginine, a potent inhibitor of nitric oxide synthase activity, without any significant enhancement of intramacrophagic mycobacterial growth . Infection with all the three mycobacterial species induced a significant activation of phospholipase A2 activity of macrophages as evidenced by the increased release of thromboxane A2 . Finally, nitric oxide production by human monocyte-derived macrophages required infection with live M . avium, as neither gamma-irradiated M . avium nor the subcellular fractions of this microorganism (cell wall, cytosol) were able to trigger nitric oxide synthesis.

Am J Respir Crit Care Med, 1994 Jul, 150(1), 261 - 5
Chronic destructive lung disease associated with a novel mycobacterium; Emler S et al.; A woman born in 1920 has suffered from a chronic destructive lung disease since 1972, with development of a severe combined restrictive and obstructive ventilatory defect . Large quantities of acid-fast microorganisms have been repeatedly observed in her sputum . Multiple courses of antimycobacterial treatment did not stop the progression of the disease . The mycobacterium involved was first identified as Mycobacterium gordonae, and later as Mycobacterium scrofulaceum . Analysis of part of the amplified gene of the 16S rRNA, however, revealed that its sequence differed from that of any established mycobacterial species, although it was observed once before in a German lymph node isolate, for which the name "Mycobacterium interjectum" has been proposed . Retrospective analysis confirmed the presence of this sequence in frozen samples which had been provided by the patient in 1983, 1985, 1989, 1990, and 1993 . Our case confirms the value of amplification and sequencing of mycobacterial 16S rRNA for classifying mycobacteria, and suggests that "Mycobacterium interjectum" may be involved in cases of chronic destructive lung disease.

Sud Med Ekspert, 1994 Jul-Sep, 37(3), 5 - 7
{A comparative study of the glucose level in dry blood stains from donors and cadavers}; Kachina NN; Glucose concentrations in dry spots of cadaveric and donor blood stored at room temperature for different periods were measured . Studies by glucose oxidase method revealed that glucose levels in dry spots of both cadaveric and donor blood gradually reduced until completely disappeared, but in comparison with glucose level lowering in liquid blood the period during which this carbohydrate completely disappeared from a dry blood spot was by several times longer . Effects of the velocity of blood spot drying and of microorganisms contaminating the sample may make the expert conclusions doubtful.

Med Hypotheses, 1994 Jul, 43(1), 6 - 10
Self and nonself: duality of immune system; Chigira M; From the viewpoint of evolution, mammalian immunity has been developed to prevent invasion by foreign bodies including parasites and microorganisms and not to survey oncogenesis . The surveillance system on oncogenesis has been lost in the evolutionary process from amphibians to mammals . The essential duality between developmental antigens and tumor specific antigens is important in explaining what the target of self-defense mechanisms is . This duality between self-defense and defense against foreign bodies originated from invertebrates as shown in insects . Immunity has been developed to survey retrodifferentiation of somatic cells and to drive the developmental process in organogenesis . Under these conditions, the clonal deletion theory of immunocyte differentiation will lose its teleological meaning . Also, the hypothesis explaining self reactivity of immunity by the immune system recognizing only an 'internal image' composed of an idio-antiidio network of immunocytes and antibodies is overly pedantic.

New Microbiol, 1994 Jul, 17(3), 249 - 53
Rapid detection of mycobacteria by combining a radiometric detection system with DNA probes; Mascellino MT et al.; Forty-four Mycobacterium-spp . were isolated in 33 patients from an infectious diseases ward . All patients were HIV-positive and most of them were drug-abusers . M . avium-intracellulare was the most common type of MOTT (Mycobacteria other than tuberculosis) detected and the only microorganism isolated in patients with mycobacteriaemia . The radiometric method performed by the Bactec system enhanced the isolation rate of mycobacteria, especially from the bloodstream . The Gen-probe DNA hybridization system proved to be rapid diagnostic tool for the identification of strains.

Infect Control Hosp Epidemiol, 1994 Jul, 15(7), 443 - 6
Viewpoint: survival benefit by selective decontamination of the digestive tract (SDD); van Saene HK et al.; Morbidity and mortality due to infection acquired either before or after admission to the intensive care unit is still a major problem . A limited range of potentially pathogenic microorganisms (PPM) are involved, and infection with these PPM usually follows a predictable pattern . Selective decontamination of the digestive tract (SDD) should be investigated further in patients with primarily curable diseases who are not infected on admission to intensive care but become infected there.

J Antimicrob Chemother, 1994 Jul, 34(1), 139 - 48
Bacteriology of selective decontamination: efficacy and rebound colonization; Tetteroo GW et al.; In earlier studies concerning the use of selective decontamination (SD) we recognized some patients to have an incomplete or failed decontamination which had negative consequences for their outcome . We also experienced patients to have a rebound colonization with potentially pathogenic microorganisms (PPM) after the withdrawal of SD medication, thereby endangering the hospital environment as sources of possibly resistant microorganisms . In a prospective observational cohort-study, we have studied 135 patients on a surgical ICU in a University hospital . On admission 51% of all patients harboured PPM, of which 64% and 79% were eliminated form the oropharynx and gut, respectively . A total of 49 episodes of SD (32%) had to be defined as ineffective, partly due to late or inadequate administration of medication . Rebound colonization with nosocomial aerobic PPM was seen in 20 of 90 successfully decontaminated episodes, but there were no infections . Eighty-four of 123 surveillance cultures (68%) revealed a complete recolonization with flora in a composition not different from the pre-admission flora . Withdrawal of SD medication 5 days after extubation proved satisfactory because no infections ensued . Surveillance cultures are obligatory to determine whether SD is effective as one third of patients receiving SD experienced bacterial colonization with PPM and therefore had no benefit from this prophylaxis . In addition, these results indicate that an intact and functional colonization resistance develops in patients after cessation of effective SD medication, but only when physiological defence mechanisms are presumably restored . In the seven years of experience with SD, increasing antibiotic resistance has not been in the study hospital.

Z Naturforsch {C}, 1994 Jul-Aug, 49(7-8), 407 - 10
7-Chloro-4,6-dimethoxy-1(3H)-isobenzofuranone and basidalin: antibiotic secondary metabolites from Leucoagaricus carneifolia Gillet (basidiomycetes) {corrected}; Huff T et al.; Two antibiotic metabolites were isolated from cultures of Leucoagaricus carneifolia . Their structures were elucidated by spectroscopic methods . The first compound, 7-chloro-4,6-dimethoxy-1(3H)-isobenzofuranone {corrected} (1) had to our knowledge not been described from natural sources whereas the second, basidalin (2), is a known metabolite of L . naucina (H . Iinuma et al., 1983) . 1 exhibits antibiotic activities with minimal inhibitory concentrations of 20 micrograms/ml against Botrytis cinerea, the most sensitive microorganism.

J Dairy Sci, 1994 Jul, 77(7), 2103 - 12
Physiology of mastitis and factors affecting somatic cell counts; Harmon RJ; Inflammation of the mammary gland that results from the introduction and multiplication of pathogenic microorganisms in the mammary gland is a complex series of events leading to reduced synthetic activity, compositional changes, and elevated SCC . The magnitude and temporal relationships of these responses vary with nutritional status, other animal factors, and the pathogen involved . Because the elevation of SCC is a response to an insult to the mammary gland and is modulated by inflammatory mediators, the major factor influencing SCC is infection status . The effects of stage of lactation, age, season, and various stresses on SCC are minor if the gland is uninfected . Except for normal diurnal variation, few factors other than infection status have a significant impact on milk SCC.

J Clin Microbiol, 1994 Jul, 32(7), 1750 - 6
Development of o.a.s.i.s., a new automated blood culture system in which detection is based on measurement of bottle headspace pressure changes; Stevens CM et al.; o.a.s.i.s . (Unipath Ltd., Basingstoke, United Kingdom) is a new automated blood culture system . The metabolism of microorganisms is detected by measuring changes in the pressure of the headspace of blood culture bottles . These changes are measured by monitoring the position of a flexible sealing septum, every 5 min, with a scanning laser sensor . This noninvasive system can detect both gas absorption and production and does not rely solely on measuring increasing carbon dioxide levels . A research prototype instrument was used to carry out an evaluation of the media, the detection system, and its associated detection algorithm . In simulated blood cultures, o.a.s.i.s . supported growth and detected a range of clinical isolates . Times to positivity were significantly shorter in o.a.s.i.s . than in the BACTEC 460 system . Results of a clinical feasibility study, with a manual blood culture system as a control, confirmed that o.a.s.i.s . was able to support the growth and detection of a variety of clinically significant organisms . On the basis of these findings, full-scale comparative clinical trials of o.a.s.i.s . with other automated blood culture systems are warranted.

In Vivo, 1994 Jul-Aug, 8(4), 613 - 9
Non-specific interstitial pneumonia (NIP): immunohistologic screening of etiologic agents; Ostermann A et al.; Non-specific interstitial pneumonia (NIP) occurs frequently in patients with HIV-infection . To elucidate the etiology of this pulmonary disorder, we searched for 13 different microorganisms in transbronchial biopsies from 15 patients with NIP, 15 patients with Pneumocystis carinii pneumonia (PCP) and 20 patients with lung diseases not related to HIV-infection using monoclonal antibodies and the APAAP- or PAP-technique for immunostaining . Chlamydia trachomatis and parainfluenza III were detected frequently and in great number . Adenovirus, influenza B, varicella zoster and cytomegalovirus were also found frequently, but not in great number . Measles virus, respiratory syncytial virus, influenza A and herpesviruses 1&2 were not found . Also not found were parainfluenza I, mycoplasma pneumoniae and coronavirus . In seven out of fifteen NIP patients at least one organism was shown, compared to nine out of fifteen patients with PCP and eight out of twenty patients in the control group.

Bioorg Med Chem, 1994 Jul, 2(7), 659 - 67
Thermostability and thermoactivity of enzymes from hyperthermophilic Archaea; Adams MW et al.; Enzymes from hyperthermophilic microorganisms are characteristically thermostable and thermoactive at extremely high temperatures . Information about the basis for the structure and function of these novel proteins is beginning to emerge . However, there are very few generalizations that can be drawn at this point that can be derived from the limited number of studies that have focused on biocatalysis and thermostability at extremely high temperatures.

Lijec Vjesn, 1994 Jul-Aug, 116(7-8), 211 - 5
{Bacterial adherence and its importance in the pathogenesis of infections}; Vranes J; Bacteria usually attack the susceptible animal or human organisms at mucosal surfaces of the respiratory, gastrointestinal or genitourinary tract . To colonize these surfaces they must penetrate a number of nonspecific defense barriers including cleansing mechanisms such as sneezing, coughing, peristalsis and fluid flow . Successful microorganisms escape recognition by soluble immune or nonimmune molecules, and bind to the mucosal surfaces via specialised molecules exposed on their surface (adhesions) which recognize and interact with complementary molecules (receptors) on the surface of specific host cells . This key step in the pathogenesis of infectious diseases is currently the subject of intensive investigation . In this review the mechanism and the role of adherence in different bacterial infections are considered.

Rev Latinoam Microbiol, 1994 Jul-Sep, 36(3), 213 - 9
{Sequential activation of cellular and humoral immunity in leprosy: considerations based on recent findings}; Rojas-Espinosa O et al.; Lepromatous leprosy in the human being evolves showing a progressive loss of cell mediated immunity (CMI) to the antigens of Mycobacterium leprae (ML) . This does not prevent the host to respond with antibodies to the same microorganism . On the other hand, the production of antibodies to the great majority of exogenous antigens results from cell-to-cell interactions that involve the participation of helper T cells . On this ground, a satisfactory explanation for the loss of CMI to M . leprae (which indicates either the loss or inactivation of specific helper T cells), with no effect on the humoral response to the same microorganism (this implying the participation of functional specific helper T cells), was difficult to found . It was not until Mosmann established, in the mouse, the existence of two subpopulations of helper T cells, that a feasible explanation for the apparent immunological paradox observed in leprosy was possible to offer . The work described here, based to a great extent in our experience on murine leprosy, refers to recent concepts concerning this issue.

J Periodontol, 1994 Jul, 65(7), 713 - 7
Effects of antibiotic treatment on clinical conditions with guided tissue regeneration: one-year results; Demolon IA et al.; The one-year results of a regenerative procedure in patients treated with or without antibiotics are presented . Expanded polytetrafluoroethylene (ePTFE) was placed over mandibular molar Class II furcation invasions and retained for four weeks . The patients in group 1 received no antibiotics; patients in group 2 received amoxicillin/clavulanate potassium during the first 10 post-operative days . The initial differences in tested microorganisms and post-surgical inflammation indicated that the use of the antibiotic might enhance the long-term outcome . After one year, the reduction in mean probing depth of the furcation invasions was 2.0 +/- 1.2 mm for group 1 and 1.8 +/- 1.1 mm for group 2 . An overall gain of 0.8 mm of clinical attachment was found . Twenty-two of the 24 sites were re-entered . Wide individual variations were found but the changes between pre-treatment and one-year data for any of 6 linear measurements of hard tissue landmarks did not differ between groups or between pre-treatment and re-entry . A combination of an overall loss of 0.4 mm alveolar bone at the crest and 0.3 mm gain of bone at the bottom of the furcation defects was found . Volumetric analysis indicated an average 32% bone fill for both groups, ranging from a decrease in defect volume by 84% (gain) to an increase of the size of the furcation invasion by 66% (loss) . A decrease in defect volume > 30% was found at 7 sites from each group . The antibiotic may have controlled initial inflammation, but 12 months later it had no direct effect on bone regeneration or soft tissue attachment.

Dtsch Med Wochenschr, 1994 Jun 24, 119(25-26), 899 - 903
{The chemotactic behavior of alveolar macrophages and blood monocytes after exposures to different NO2 concentrations}; Kienast K et al.; The chemotaxis of alveolar macrophages (AM) and blood monocytes (BM) is important in the elimination of particles and microorganisms which have invaded the lung . The effect of nitrogen dioxide (NO2) on chemotaxis was tested on AM obtained by diagnostic bronchoscopy from five patients suspected of having bronchial carcinoma (four men, one woman; mean age 59 +/- 10 years) . Blood monocytes were also studied with blood from seven healthy subjects (five men, two women; mean age 32 +/- 10 years) . These cells were placed on polycarbonate membranes for 15 min each, exposed to NO2 concentrations between 1.0 and 5.0 parts per million (ppm), and then incubated with complement component C5a as chemotactically active agent . The number of AM or BM which actively migrated through the polycarbonate membrane under the influence of C5a was measured by means of a light microscope . The migration rate of AM (compared to air exposure) was reduced by 33% with 1.0 ppm NO2 and by 61% with 5.0 ppm . The migration rate of BM in similar conditions was reduced by as much as 55% . There was no significant cytotoxic effect of NO2 exposure at 1.0 and 3.0 ppm . With 5.0 ppm 13.0 +/- 3.0 cells were no longer viable . These results indicate that NO2 concentrations relevant to indoor conditions affect the chemotaxis of AM and BM after short-time NO2 exposures . The data further suggest that NO2 exposures of these cells depressed chemotactic mechanisms without relevant cytotoxicity.

Cancer Res, 1994 Jun 15, 54(12), 3305 - 14
Expression of carcinoembryonic antigen and nonspecific cross-reacting 50-kDa antigen in human normal and cancerous colon mucosa: comparative ultrastructural study with monoclonal antibodies; Baranov V et al.; The precise localization of carcinoembryonic antigen (CEA) and non-specific cross-reacting 50-kDa antigen (NCA 50) in normal colon mucosa and colon adenocarcinoma was investigated by using an indirect immunoperoxidase electron microscopic technique with specific monoclonal antibodies . In normal adult colon both antigens were localized to microvesicles and filaments of the "fuzzy coat" on the apical surface of the epithelial cells . In addition, NCA 50 was found in the narrow spaces between adjoining microvilli . Mature columnar cells at the free luminal surface contained most of the antigen positive material . CEA and NCA 50 were also detected as intracellular components of goblet cells . In multilayered tumor glands, the cell surface expression of the antigens was dependent on the position of the tumor cell in the gland . The neoplastic cells showed either a predominant apical labeling or a positive staining of almost the entire cell surface . Some of the neoplastic cells contained CEA in so-called "intracellular lumina." In contrast to normal colon epithelial cells most tumor cells synthesized NCA 50 actively . In normal colonic mucosa, unlike in cancerous tissue, CEA and NCA 50 appear to be released via vesicles formed from the microvillous membrane of mature columnar cells . These results are consistent with the hypothesis that CEA and NCA play a role in the nonspecific defense against microorganisms in the large intestine.

Science, 1994 Jun 10, 264(5165), 1551 - 7
How nature builds the pigments of life: the conquest of vitamin B12; Battersby AR; In part because humans cannot synthesize vitamin B12 and must obtain it from organisms that produce it and because B12 deficiency leads to pernicious anemia, it has been important to understand how microorganisms build this quite complex substance . As shown here, an interdisciplinary attack was needed, which combined the strengths of genetics, molecular biology, enzymology, chemistry, and spectroscopy . This allowed the step-by-step synthetic pathway of B12 to be elucidated, and this approach has acted as a model for future research on the synthesis of substances in living organisms . One practical outcome of such an approach has been the improved availability of B12 for animal feedstuffs and human health.

Neuroreport, 1994 Jun 2, 5(10), 1201 - 4
Further ultrastructural evidence that spirochaetes may play a role in the aetiology of Alzheimer's disease; Miklossy J et al.; Recently it was reported that, at autopsy, in neuropathologically confirmed cases of Alzheimer's disease spirochaetes were found in blood and cerebrospinal fluid using dark-field microscopy . Moreover, the spirochaetes were isolated and cultured from brain tissue . We now show, using scanning electron microscopy and atomic force microscopy that the helically shaped microorganisms isolated and cultured from the Alzheimer brains possess axial filaments . This indicates that these microorganisms taxonomically indeed belong to the order Spirochaetales . A morphometric analysis reinforces this notion.

Toxicol Appl Pharmacol, 1994 Jun, 126(2), 214 - 23
Effects of benzene metabolites on receptor-mediated phagocytosis and cytoskeletal integrity in mouse peritoneal macrophages; Manning BW et al.; Exposure to benzene can induce a number of hematotoxicities and decrease host resistance to microorganisms and tumors . Several studies have shown that metabolism of benzene to reactive intermediates is required for myelotoxicity . Since receptor-mediated phagocytosis by macrophages is an important host defense, we have examined the effects of benzene metabolites on receptor-mediated phagocytosis in cultured murine peritoneal macrophages . 1,4-Benzoquinone (BQ) was the most potent of the metabolites examined . Ten-minute exposures to a 12.5 microM concentration inhibited Fc and complement receptor-mediated phagocytosis by > or = 90% . Macrophage viability was largely unaffected by BQ treatment . Exposure to 50 and 100 microM 1,2,4-benzenetriol (BT) inhibited Fc receptor-mediated phagocytosis by 70 and 95%, respectively . Hydroquinone (HQ) elicited a major decrease (50%) only at 100 microM . The comparative inhibitory potencies of BT and HQ correlate with previously published data on their relative facility for autooxidation to quinones at physiological pH . Catechol had no effect at the concentrations employed . Macrophages treated with BQ and BT failed to recover their Fc receptor-mediated phagocytic capacity when incubated overnight in the absence of the xenobiotics . Only small differences in the inhibition of Fc receptor-mediated phagocytosis were observed between macrophages exposed to BQ at 4 versus 37 degrees C . BQ also had little effect on the Fc receptor binding of target cells . Fluorescent digital imaging microscopy demonstrated that BQ treatment markedly decreased the filamentous actin content of macrophages . However, BQ bound in low amounts to purified actin and did not affect its assembly . Our findings suggest that a mechanism for inhibition of Fc receptor-mediated phagocytosis by BQ is disruption of filamentous actin via an effect(s) other than the direct alkylation of actin by BQ.

J Lab Clin Med, 1994 Jun, 123(6), 808 - 16
Newly recognized causes of atherosclerosis: the role of microorganisms and of vascular iron overload; Jacob HS; We have hypothesized that shear stresses at sites of increased vascular turbulence may foster atherogenesis by two previously unknown mechanisms: The first involves Herpes virus activation, which can provoke direct or inflammatory cell-mediated endothelial damage while altering the vascular surface to a highly procoagulant entity . The second derives from red blood cell fragmentation, with resulting uptake by endothelium of released heme groups . In this instance the opening of the heme ring by induced endothelial heme oxygenase frees iron, which sensitizes cells to damage by oxidants--for instance, those generated by closely apposed inflammatory cells . An additional injurious effect of released heme results from its potent catalysis of LDL oxidation--a process specifically and rapidly inhibited by oral supplementation of vitamin E . Although heme-protein's deleterious actions can be counteracted by the plasma constituents haptoglobin and hemopexin, we suggest that these may not be sufficiently present in "sanctuary" sites of vessel walls such as in intramural hemorrhages associated with atherosclerotic intimal tears.

Surg Clin North Am, 1994 Jun, 74(3), 609 - 20
Infections in the immunocompromised patient; Howard RJ; Specific microorganisms have certain types of host defenses directed at them . Inhibition of different host defenses, therefore, leads to an increased risk of the host for infection with different organisms . This article discusses the types of infections present in immunocompromised patients as well as a general approach to diagnosis and treatment.

Infect Immun, 1994 Jun, 62(6), 2619 - 21
Infection of human endothelial cells by Rickettsia rickettsii causes a significant reduction in the levels of key enzymes involved in protection against oxidative injury; Devamanoharan PS et al.; The activities of glucose-6-phosphate dehydrogenase, catalase, and glutathione peroxidase were significantly decreased in human endothelial cells infected with the obligate intracellular bacterium Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever . This observation lends additional support to our hypothesis implicating oxidative damage in endothelial cell injury caused by this microorganism.

Infect Immun, 1994 Jun, 62(6), 2409 - 16
Mycoplasma arthritidis-derived superantigen induces proinflammatory monokine gene expression in the THP-1 human monocytic cell line; al-Daccak R et al.; Soluble factors produced by Mycoplasma arthritidis play an important role in the pathology of arthritis in rodents, which closely resembles human rheumatoid arthritis . At least one of the products of these microorganisms, M . arthritidis-T cell mitogen (MAM), has biological activities in common with superantigens . These superantigens activate T cells in a V beta-restricted fashion, and this response is strictly dependent on the presence of major histocompatibility complex (MHC) class II-positive cells . In the present study, we have examined the ability of MAM to induce proinflammatory monokine (interleukin 1 beta {IL-1 beta} and tumor necrosis factor alpha {TNF-alpha}) gene expression in the THP-1 monocytic cell line . Treatment of these cells (which express a very low level of HLA-DR molecules) with gamma interferon (INF-gamma) induced HLA-DR, -DQ, and -DP molecules and enabled them to respond to MAM in a dose-dependent manner, resulting in an increase in the level of steady-state mRNA for IL-1 beta and TNF-alpha . Stimulation of the U937 monocytic cell line (MHC class II-negative even after INF-gamma treatment) with MAM did not induce either IL-1 beta or TNF-alpha transcription . Moreover, MAM adsorption on Raji (MHC class II-positive) cells resulted in the loss of its cytokine-inducing activity to induce monokine gene expression . These findings demonstrate clearly that MAM induces monokine gene expression following interaction with MHC class II molecules . Pretreatment of INF-gamma-treated THP-1 cells with the transcription inhibitor actinomycin D prevented the induction of monokine mRNA, whereas cycloheximide superinduced mRNA after stimulation with MAM . Finally, our results, obtained with protein tyrosine kinase inhibitors and antiphosphotyrosine Western blotting (immunoblotting), indicate that protein tyrosine kinase is involved in MAM-induced IL-1 beta and TNF-alpha gene expression in the THP-1 monocytic cell line . The capacity of MAM to induce proinflammatory cytokine transcription in monocytes via MHC class II molecules can be one pathway of MAM contribution to autoimmune diseases.

Infect Immun, 1994 Jun, 62(6), 2169 - 77
Specific interaction of Aspergillus fumigatus with fibrinogen and its role in cell adhesion; Coulot P et al.; Interaction between Aspergillus fumigatus conidia and different proteins known to mediate the attachment of malignant tumor cells or microorganisms to the host tissues was studied in vitro . Flow cytometry using fluorescein isothiocyanate-conjugated fibrinogen confirmed that binding of human fibrinogen to the conidia was dose dependent and specific . Binding was inhibited by unlabeled fibrinogen and by basement membrane laminin . Moreover, the expression of fibrinogen receptors at the surfaces of conidia seemed to be related to the maturation of the conidia . Binding sites appeared to be located in the D domains of the fibrinogen molecule . However, the peptide sequence recognized by the fungus could not be identified but was different from the classical adhesive recognition sequences, RGDS and fibrinogen gamma-chain dodecapeptide . In addition, an assay of adherence to proteins immobilized onto microtiter plates allowed us to establish the role of these interactions in fungal adhesion . Conidia strongly adhered to human fibrinogen and to laminin but not to fibronectin . Adhesion to fibrinogen substrates was specific, since it was inhibited by soluble fibrinogen and by specific antibodies, and seemed to be mediated by the D domains of the molecule . Study of the adhesion of numerous strains or clinical isolates to various mammalian fibrinogens did not reveal any particular affinity of strains for some animal species . Finally, by cultivation of the fungus in the presence of 125I-human fibrinogen and analysis of the radiolabeled material bound to the surface of the fungus, we were able to specify the sequence of events allowing its installation within the host . The interactions identified here may play an important role in governing fungal adherence and host tissue invasion.

Antimicrob Agents Chemother, 1994 Jun, 38(6), 1219 - 24
Single-dose pharmacokinetics of oral fleroxacin in bacteremic patients; Schrenzel J et al.; Fleroxacin is a new broad-spectrum quinolone which can be given by the oral route . The present study was designed to assess the influence of bacteremia on the pharmacokinetics of a single oral dose of fleroxacin . Thirteen patients with proven bacteremia (one or more pairs of positive blood cultures, no hypotension) were given a single 400-mg fleroxacin dose orally on two occasions while also receiving standard antibiotic therapy . The first dose was administered 12 to 36 h after the last positive blood culture was drawn (day 1), and a second dose was administered 7 days later (day 7 +/- 2) to compare the pharmacokinetics between the acute and the convalescent phases of the disease . Following each administration of fleroxacin, serial plasma samples were collected for up to 72 h and were analyzed for unchanged drug by a reversed phase high-pressure liquid chromatography technique . There were no significant changes in the following pharmacokinetic parameters (mean standard deviation) the maximum concentration of drug in serum (6.4 +/- 1.5 versus 6.7 +/- 1.9 mg/liter), the minimum concentration of drug in serum, defined as the concentration of drug in serum at 24 h postdose (3.0 +/- 1.7 versus 2.5 +/- 1.2 mg/liter), the time to the maximum concentration of drug in serum (2.3 +/- 1.4 versus 2.0 +/- 1.2 h), and the elimination half-life (19.7 +/- 8.0 versus 17.9 +/- 6.9 h) . Fleroxacin clearances were compared for each individual patient . A positive correlation (R2 = 0.787) was found between the values measured on day 1 and day 7 . Oral clearance of fleroxacin (CL = CL/F, where F is bioavailability was slightly, but not significantly, reduced during the bacteremic phase (oral clearance, 43.8+/- 23.5 versus 48.5 +/- 17.5 ml/min.) . When compared with previous results obtained in healthy young subjects, longer times to the maximum concentration of drug in serum and elimination half-lives and higher areas under the curve were observed . This could be due to the bacteremic state, the old age of the patients (mean, 66 years), and the low renal clearance (mean calculated creatinine clearance, 71.1 ml/min) . A single oral dose of 400 mg of fleroxacin provides sufficient levels in serum to cover susceptible microorganisms for at least 24 h in bacteremic patients . Renal function appeared to be the key element that had to be taken into consideration to adapt fleroxacin dosage profiles in our patient population . Bacteremia itself appeared to amplify that phenomenon, but to a much lesser extent than renal function did.

Ophthalmic Surg, 1994 Jun, 25(6), 361 - 4
En bloc capsulectomy in the diagnosis and treatment of refractory, chronic, recurrent pseudophakic endophthalmitis; Thach AB et al.; Anterior chamber and vitreous aspiration may fail to isolate a microorganism in chronic pseudophakic endophthalmitis . In some eyes, obtaining a portion of the central posterior lens capsule may assist in determining the infectious etiology of the endophthalmitis . We describe a technique by which the entire lens capsule and its internal contents are removed and cultured . This surgical method facilitated the isolation and eradication of the causative pathogen in a patient with chronic recurrent pseudophakic endophthalmitis that was diagnostically and therapeutically refractory to previous vitrectomy, posterior capsulectomy, and intravitreal antibiotic injection.

Geburtshilfe Frauenheilkd, 1994 Jun, 54(6), 337 - 40
{Ciprofloxacin/metronidazole vs . cefoxitin/doxycycline: comparison of two therapy schedules for treatment of acute pelvic infection}; Fischbach F et al.; The efficacy and safety of two antibiotic regimens for the treatment of acute pelvic inflammatory disease (PID) was compared in a prospective and randomised study . 57 patients received either 0.2 gms ciprofloxacin intravenously b.i.d . in combination with 0.5 g metronidazole intravenously t.i.d . (n = 26), or alternatively 2 g cefoxitin intravenously t.i.d . in combination with doxycycline 0.1 g b.i.d . (n = 31) . After commencing therapy intravenously, medication with ciprofloxacin, metronidazole and doxycycline was continued orally after two or three days . In the ciprofloxacin/metronidazole group, PID was found to be severe in 7, moderate in 12 and mild in 7 patients . The numbers in the cefoxitin/doxycycline group were 8, 20 and 3 respectively . The clinical result after treatment with ciprofloxacin/metronidazole was resolution of all symptoms in 24 patients and improvement in 2 others . In the cefoxitin/doxycycline treated group, resolution was found in 27 patients, improvement in 2 others . Failure occurred in 2 patients . 53 different microorganisms as the suspected cause of PID were isolated in the ciprofloxacin/metronidazole group and 56 in the cefoxitin/doxycycline group . According to our clinical and bacteriological criteria, treatment for PID was successful in 97% of the ciprofloxacin/metronidazole group and in 87% of the cefoxitin/doxycycline group . Adverse reactions were found in 4 patients in the ciprofloxacin/metronidazole treated group . Therapy had to be terminated in 3 of these patients . In the cefoxitin/doxycycline group 2 patients had adverse reactions, and therapy had to be terminated in one of these patients . According to our results, both antibiotic regimens can be recommended for the treatment of PID.

J Periodontol, 1994 Jun, 65(6), 576 - 82
Comparison of DNA probe and ELISA microbial analysis methods and their association with adult periodontitis; Melvin WL et al.; The purposes of this study were two-fold: to compare the DNA probe and enzyme linked immunosorbent assay (ELISA) microbial identification tests and correlate the levels of microorganisms with adult periodontitis . A single plaque sample were taken from each of 2 sites in 52 patients . Twelve of these patients were also sampled during and after treatment . The experimental site had clinical indicators of disease (bleeding on probing, probing and attachment loss of > or = 6 mm) and the contralateral site (control) was clinically healthy . A total of 176 plaque samples were collected, divided, processed, and sent for both types of quantitative microbial analyses . All of these samples were used to compare the DNA probe and ELISA methods while only the initial 104 pretreatment sites were used to correlate microorganisms/method with clinical indicators of adult periodontitis . DNA probes were used to assay for A . actinomycetemcomitans, P . gingivalis, P . intermedia, E . corrodens, F . nucleatum, T . denticola, and C . rectus . An ELISA utilizing monoclonal antibodies was used to assay for P . gingivalis, E . corrodens, T . denticola, and C . rectus . Comparison of the two methods revealed that the ELISA test identified P . gingivalis and C . rectus significantly more often than the DNA probe method and that T . denticola was detected more frequently with the DNA probe . The sensitivities and specificities varied widely among organisms and by test . P . gingivalis, as identified by ELISA, had the highest degree of sensitivity and specificity (0.90 and 0.82 respectively) to clinical indicators of adult periodontitis.

J Clin Microbiol, 1994 Jun, 32(6), 1488 - 91
Comparison of BACTEC Plus 26 and 27 media with and without fastidious organism supplement with conventional methods for culture of sterile body fluids; Fuller DD et al.; We compared the BACTEC Plus 26/27 culture system (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.) with and without fastidious organism supplement with conventional centrifugation preparation and plating for the recovery and speed of detection of microorganisms . A total of 1,101 sterile body fluid specimens were collected and processed at five hospital laboratories, yielding 234 (21%) positive cultures . Of the 176 isolates considered clinically significant, 133 (76%) were recovered by both the BACTEC system and conventional culture, while 28 (16% {P < 0.005}) were recovered by BACTEC only and 11 (6%) were recovered by conventional culture alone . There were no statistically significant differences in the speed of detection of microbial growth . It was found that BACTEC, with or without the addition of fastidious organism supplement, exhibited improved sensitivity for the recovery of microorganisms, including fastidious bacteria.

Vet Hum Toxicol, 1994 Jun, 36(3), 199 - 202
The effect of long-term exposure to anthio on serum esterases and ruminal microorganisms of male calves; Awal MD et al.; The effect of long-term exposure to the organophosphate insecticide Anthio on serum esterases and ruminal microorganisms of male calves was investigated . The daily oral administration of 3, 6 or 12 mg Anthio/kg/d for 90 d caused significant inhibition of serum cholinesterase (10-28%) and carboxylesterase (12-33%) in male calves . Toxic signs characteristic of anticholinesterase poisoning were observed during 25-70 d of exposure to 6 and 12 mg Anthio/kg . The dose of 12 mg Anthio/kg was lethal to 1/5 calves . Total protozoal population was decreased significantly (15-27%) following 6 and 12 mg Anthio/kg, whereas reduction in total bacterial population (18%) was only significant at 12 mg Anthio/kg.

Math Biosci, 1994 Jun, 121(2), 127 - 39
The attractiveness of the Droop equations . II . Generic uptake and growth functions; Oyarzun FJ et al.; In a recent paper the authors proved global asymptotic stability of the Droop equations . This system of nonlinear ordinary differential equations describes the growth of a microorganism in a chemostat . In this setting the growth rate of the organism is limited by the availability of a single nutrient . The state variables of the Droop system are biomass density, intracellular nutrient concentration . (I"cell quota" in Droop's terminology), and extracellular nutrient concentration . In the current paper the authors relax Droop's particular choices for the uptake and growth functions . Characterizing these functions in qualitative terms only, they again reach the same conclusion of global asymptotic stability . Their analysis relies on reducing the three-dimensional Droop system to a two-dimensional system via the first integral of Burmaster.

Mol Microbiol, 1994 Jun, 12(5), 799 - 809
Identification of a novel sugar-H+ symport protein, FucP, for transport of L-fucose into Escherichia coli; Gunn FJ et al.; L-Fucose (6-deoxy-L-galactose) is used as sole carbon source by many microorganisms, and its transport into Escherichia coli is mediated by an L-fucose-H+ symport activity . In order to determine the nature of a putative transporter encoded by the E . coli fucP gene and identify its protein product it was cloned downstream of the inducible T7 RNA polymerase and lambda OLPL promoters . Induction of the T7 promoter resulted in the expression of {14C}-L-fucose uptake activity and the concomitant expression of a {35S}-Met-labelled 32 kDa protein at levels too low for detection by staining with Coomassie brilliant blue or for protein sequencing . Induction of the lambda OLPL promoter caused the appearance of L-fucose-H+ symport activity and of a Coomassie brilliant blue-stained 32 kDa membrane protein expressed at high levels sufficient for identification as FucP by N-terminal protein sequencing . The FucP protein is, therefore, a sugar-H+ symporter different in amino acid sequence from any other known transporter . These and other results illustrate the general unpredictability of cloning strategies for attempting the amplified expression of membrane transport proteins.

Rinsho Byori, 1994 Jun, 42(6), 615 - 21
{Gene level diagnostics of infectious diseases}; Miyachi H et al.; Recent developments in medical technology have caused a great change in infectious diseases, as characterized by epidemics of antibiotics-resistant bacteria, opportunistic infection in compromised hosts, and blood-borne viral infections such as hepatitis virus and human immunodeficiency virus . In the diagnosis of such new aspects of infectious diseases, conventional immunological, culture, and microscopical techniques are not always practical . By contrast, evaluation of infectious agents using molecular biological technology frequently offers the rapid, most accurate and sensitive method of diagnosis . Amplification methods are particularly attractive for the detection of small numbers of microorganisms, as in latent conditions, or for the fastest identification of the pathogen without laborious isolation . For introduction of the tests into routine procedures, their standardization as well as simplicity and low cost are required . Gene level diagnostics should be applied appropriately to management of infectious diseases along with the conventional techniques, while further roles of the tests must be determined, on the basis of the molecular elucidation of infectious diseases.

FEMS Microbiol Rev, 1994 Jun, 14(2), 139 - 60
Bacterial genomics; Cole ST et al.; During the last decade, great advances have been made in the study of bacterial genomes which is perhaps better described by the term bacterial genomics . The application of powerful techniques, such as pulsed-field gel electrophoresis of macro-restriction fragments of genomic DNA, has freed the characterisation of the chromosomes of many bacteria from the constraints imposed by classical genetic analysis . It is now possible to analyse the genome of virtually every microorganism by direct molecular methods and to construct detailed physical and gene maps . In this review, the various practical approaches are compared and contrasted, and some of the emerging themes of bacterial genomics, such as the size, shape, number and organisation of chromosomes are discussed.

FEMS Microbiol Rev, 1994 Jun, 14(2), 121 - 37
Copper resistance mechanisms in bacteria and fungi; Cervantes C et al.; Copper is both an essential micronutrient and a toxic heavy metal for most living cells . The presence of high concentrations of cupric ions in the environment promotes the selection of microorganisms possessing genetic determinants for copper resistance . Several examples of chromosomal and plasmid copper-resistance systems in bacteria have been reported, and the mechanisms of resistance have started to be understood at the molecular level . Bacterial mechanisms of copper resistance are related to reduced copper transport, enhanced efflux of cupric ions, or copper complexation by cell components . Copper tolerance in fungi has also been ascribed to diverse mechanisms involving trapping of the metal by cell-wall components, altered uptake of copper, extracellular chelation or precipitation by secreted metabolites, and intracellular complexing by metallothioneins and phytochelatins; only the metallothionein chelation mechanism has been approached with molecular detail.

Scand J Immunol, 1994 Jun, 39(6), 613 - 7
Mycobacterial heat-shock protein 65 induces proinflammatory cytokines but does not activate human mononuclear phagocytes; Peetermans WE et al.; The 65 kDa heat-shock protein (Hsp65), a well-conserved and immunodominant antigen which elicits a cellular and humoral immune response, may play a role in host defence against invading microorganisms and autoimmune disorders . The aim of the present study was to assess the effects of Hsp65 on the functional activities of human mononuclear phagocytes in the absence of lymphocytes . Incubation with Hsp65 resulted in an enhanced release of TNF-alpha and IL-1 beta by human monocytes and monocyte-derived macrophages (MDM) . The amount of cytokines released by these cells in response to Hsp65 was similar to that released in response to IFN-gamma together with LPS . Incubation with ovalbumin did not stimulate the release of these cytokines . In vitro stimulation of monocytes with Hsp65 enhanced the membrane expression of complement receptor III but did not influence either the expression of Fc gamma-receptor I and HLA class-II antigens or the release of reactive oxygen intermediates . Therefore, Hsp65-stimulated monocytes cannot be considered to be activated according to classical criteria . The release of the proinflammatory cytokines TNF-alpha and IL-1 beta by human mononuclear phagocytes in response to Hsp65 indicates that this protein can contribute to both host defence and tissue damage in inflammatory lesions characterized by an abundant expression of Hsp65.

Int J Androl, 1994 Jun, 17(3), 127 - 34
Peroxidase-positive round cells and microorganisms in human semen together with antibiotic treatment adversely influence the outcome of in-vitro fertilization and embryo transfer; De Geyter C et al.; Human semen contains not only spermatozoa but also other cells routinely differentiated as being peroxidase-positive (e.g . leucocytes) and peroxidase-negative (e.g . immature germ cells and lymphocytes) cells . Considerable uncertainty exists about their role in male fertility . To assess the clinical value of both parameters, and of microorganisms in semen, 391 treatments with in-vitro fertilization and embryo transfer were analysed retrospectively, and the concentrations of both peroxidase-positive and -negative cells, together with the presence of microorganisms in semen, were compared with both the fertilization and pregnancy rates . The data indicate that the results of treatment were affected only by excessively elevated concentrations of peroxidase-positive cells (> 6 x 10(6)/ml) and only marginally by the presence of microorganisms in the semen . The pregnancy rate after in-vitro fertilization and embryo transfer was not improved by antibiotic treatments preceding gamete recovery by several weeks . The increased presence of peroxidase-negative cells (e.g . germ cells) in semen was not associated with a significant change in the pregnancy rate . However, the concentration of peroxidase-negative cells in semen correlated significantly with sperm numbers (p < 0.01), sperm concentration (p < 0.01), and normal morphology rates (p < 0.01) . It is concluded that short-term antibiotic treatment of asymptomatic patients before assisted reproduction should be handled with caution . The widespread view that peroxidase-negative cells in semen are harmful is rejected.

Immunol Lett, 1994 Jun, 40(3), 279 - 85
Ageing alters the competence of the immune system to control parasitic infection; Albright JW et al.; The elderly are more susceptible to infections with various pathogenic organisms that are young-adults or middle-aged individuals . Certain microorganisms that are non-pathogenic in adults may cause serious infections in the elderly . This heightened susceptibility of the elderly is most likely a reflection of the age-associated decline in the competence of the immune system . It appears that the population of T cells is altered with advanced age and, possibly, the efficiency of the monocyte/macrophage cells to destroy microbial invaders declines . There is a small, but compelling, body of literature which shows that the elderly are particularly susceptible to protozoan and metazoan parasites . We have studied the markedly increased severity of infections in aged mice with the mouse-specific Trypanosoma musculi; both the parasite burden and the duration of infection are substantially greater in old compared to young mice . It appears that this difference is due, to a large extent, to the relatively weak ability of aged animals to generate cytokines associated with the TH1 subset of CD4+ T cells; in particular, the weak ability to generate IL-2 and IFN gamma which are involved in the selective expression of curative, parasite-specific antibody of the IgG2a isotype . A striking difference between young and aged mice is in the response of IL-3 producing cells to the parasite infection; IL-3-producers decline during infection in young mice but increase markedly in aged animals . There are several advantages to using T . musculi as a prototype pathogen for studying age-related susceptibility to infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Vet Res, 1994 Jun, 55(6), 803 - 9
Isolation and partial polypeptide characterization of bovine neutrophil plasma membranes; Salgar SK et al.; The neutrophil plasma membrane has a major role in migration, phagocytosis, and destruction of microorganisms . Neutrophils isolated from blood and mammary secretions were homogenized, and the plasma membrane fraction was isolated on discontinuous sucrose gradient (20, 32, and 50%) . Purity of plasma membrane preparation was determined by use of marker enzyme analysis . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the membrane proteins was performed under reducing conditions for polypeptide characterization . The membrane proteins were also labeled with 125I externally, using 1,3,4,6-tetrachloro-3 alpha-6 alpha-diphenylglycouril, and proteins were separated by SDS-PAGE and autoradiographed . Compared with whole cell homogenate, the plasma membrane fraction obtained at the 20/32% interface was enriched for the marker enzymes, 5'-nucleotidase (16-fold), alkaline phosphatase (5.5-fold), and total phosphatase (26-fold) . The membrane fraction had minimal specific activity for beta-glucuronidase (0.4-fold), compared with whole cell homogenate . Plasma membrane protein yield was about 500 micrograms/10(9) bovine blood neutrophils . The SDS-PAGE of plasma membrane proteins revealed 25 protein bands, of which 13 were major bands . There were 3 distinct bands (18, 36, and 65 kd) in the plasma membrane-enriched fraction (20/32 interface) that were not seen in other fractions (30/50% and pellet) . Further, 125I-labeling identified 5 distinct protein bands (205, 140, 65, 35, and 30 kd) . Blood and mammary neutrophils had similar polypeptide patterns, except that 36- and 65-kd bands were more prominent for blood neutrophils than for mammary neutrophils.

Pharm Res, 1994 Jun, 11(6), 777 - 83
Pharmaceutical applications of microcalorimetry; Koenigbauer MJ; General principles and applications of microcalorimetry are reviewed . Microcalorimetry is useful in the study of physical, chemical, and biological drug interactions . The sensitivity of the present instrumentation is approximately 0.1 microW . With this high sensitivity, additional applications have been developed, including the interactions of drugs with food, lymphoma cells, microorganisms, blood, excipients, and cyclodextrin . A recent application of microcalorimetry is the measurement of degradation rates of drugs.

Mol Microbiol, 1994 Jun, 12(6), 859 - 64
A-factor as a microbial hormone that controls cellular differentiation and secondary metabolism in Streptomyces griseus; Horinouchi S et al.; A-factor, containing a gamma-butyrolactone in its structure, is an autoregulatory factor or a 'microbial hormone' controlling secondary metabolism and cellular differentiation in Streptomyces griseus . A-factor exerts its regulatory role by binding to a specific receptor protein which, in the absence of A-factor, acts as a repressor-type regulator for morphological and physiological differentiation . In the signal relay leading to streptomycin production in S . griseus, the A-factor signal is transferred from the A-factor receptor to the upstream activation sequence of a regulatory gene, strR, in the streptomycin biosynthetic gene cluster via an A-factor-dependent protein that serves as a transcription factor for strR . The StrR protein thus induced appears to activate the transcription of other streptomycin-production genes . The presence of A-factor homologues in a wide variety of Streptomyces species and distantly related bacteria implies the generality of gamma-butyrolactones as chemical cellular signalling molecules in microorganisms.

Curr Opin Immunol, 1994 Jun, 6(3), 458 - 66
Role of cytokines in determining T-lymphocyte function; O'Garra A et al.; Early events in an immune response stimulate the production of cytokines that direct the subsequent development of T-helper (Th) subsets with discrete patterns of cytokine production . These events are dictated by the type of antigen/microorganism administered to a host, as well as dose and route of immunization . Bacterial stimuli activate macrophages of the innate immune response to produce IL-12 and drive Th1 development and cell-mediated immunity . Conversely, production of IL-4 early in an immune response favors a Th2 or allergic/humoral immune response . The ability of IL-4 and IL-10 to inhibit Th1 development and effector function, as well as the requirement of committed Th1 cells for co-stimulators to induce maximal IFN-gamma production, suggests that cell-mediated immunity is under strict control, probably to achieve immunity with minimum immunopathology.

Zentralbl Hyg Umweltmed, 1994 Jun, 195(5-6), 366 - 76
{Biologic degradation of phenoxypropanolene . Biodegradability of phenoxypropanols}; Goroncy-Bermes P et al.; Phenoxypropanols have been used for some time as ingredients in surface and instrument disinfectants . Since the residual solutions of these preparations are discharged into the waste-water, the biodegradability of the ingredients used is of great importance . Tests by means of the Zahn-Wellens test in accordance with OECD guidelines have shown that phenoxypropanols are biodegradable . In further studies it was investigated whether unwanted intermediate products are formed in considerable amounts . Of particular interest was the question of the possible development of phenol outside the bacterial cells . To test the biodegradability of the aromatic alcohols and to ascertain whether there is extracellular formation of phenol, microorganisms were isolated from the municipal sewage plant at Stellinger Moor, Hamburg, and from water from the River Elbe . Phenoxypropanol-containing solutions were then inoculated with the bacteria and incubated at 30 degrees C . At regular intervals both the concentration of the alcohols was determined and the test for phenol was performed by means of liquid chromatography on reverse phase material (RP 18) and detection with a photodiode array detector . The breakdown of the phenoxypropanols was monitored for a period of up to 4 weeks . During this period a clear breakdown of the aromatic alcohols was observed . No phenol was detected.

Microbiol Rev, 1994 Jun, 58(2), 162 - 210
Analysis of the sequence and gene products of the transfer region of the F sex factor; Frost LS et al.; Bacterial conjugation results in the transfer of DNA of either plasmid or chromosomal origin between microorganisms . Transfer begins at a defined point in the DNA sequence, usually called the origin of transfer (oriT) . The capacity of conjugative DNA transfer is a property of self-transmissible plasmids and conjugative transposons, which will mobilize other plasmids and DNA sequences that include a compatible oriT locus . This review will concentrate on the genes required for bacterial conjugation that are encoded within the transfer region (or regions) of conjugative plasmids . One of the best-defined conjugation systems is that of the F plasmid, which has been the paradigm for conjugation systems since it was discovered nearly 50 years ago . The F transfer region (over 33 kb) contains about 40 genes, arranged contiguously . These are involved in the synthesis of pili, extracellular filaments which establish contact between donor and recipient cells; mating-pair stabilization; prevention of mating between similar donor cells in a process termed surface exclusions; DNA nicking and transfer during conjugation; and the regulation of expression of these functions . This review is a compendium of the products and other features found in the F transfer region as well as a discussion of their role in conjugation . While the genetics of F transfer have been described extensively, the mechanism of conjugation has proved elusive, in large part because of the low levels of expression of the pilus and the numerous envelope components essential for F plasmid transfer . The advent of molecular genetic techniques has, however, resulted in considerable recent progress . This summary of the known properties of the F transfer region is provided in the hope that it will form a useful basis for future comparison with other conjugation systems.

Zentralbl Bakteriol, 1994 Jun, 281(1), 102 - 6
No cultural detection of Helicobacter pylori in dental plaque; Von Recklinghausen G et al.; Helicobacter pylori causes human type B gastritis and is involved in the etiology of peptic ulcer disease . The routes of transmission of H . pylori are still unclear . The microorganism may be transmitted orally, since H . pylori has been detected in dental plaques . To confirm the hypothesis that dental plaques are a reservoir of H . pylori, 100 dental plaque specimens from 55 dental surgery patients were incubated on one nonselective and up to four selective agar media for the detection of H . pylori . In addition, urease activity of the plaque material was tested, and the gingival status of the patients was assessed . H . pylori was not cultivated from any of the specimens investigated . Plaque material from 12 patients with moderate and severe gingivitis showed urease activity . The results do not confirm the hypothesis that dental plaques are a relevant reservoir of viable H . pylori cells . However, non-cultivatable forms of H . pylori may survive in dental plaques . Urea cleaving activity of dental plaque may be a marker of gingival inflammation.

Ecotoxicol Environ Saf, 1994 Jun, 28(1), 71 - 81
Fate of a volatile chlorinated solvent in indoor aquatic microcosms: sublethal and static exposure to {14C}dichloromethane . Groupe pour l'Etude du Devenir de Xénobiotiques dans l'Environnement (GEDEXE); Thiebaud H et al.; The goal of this work was to study the fate of dichloromethane in indoor aquatic microcosms after a sublethal and static exposure to simulate the accidental contamination of a lenitic ecosystem such as littoral lake zone or a pond . This kind of ecosystem is characterized by high productive capacity and rich biocoenose, and are usually first affected by acute or chronic pollution . Microcosms containing immersed bryophytes (Fontinalis antipyretica), macrophytes (Lemna minor, Groenlendia densa, Elodea canadensis), molluscs (Physa fontinalis), crustaceans (Daphnia magna), and unicellular green algae (Scenedesmus subspicatus) were contaminated with sublethal concentrations of dichloromethane or {14C}dichloromethane . The initial mean concentration was 9.9 +/- 3.7 microM . The mean concentration exposure for organisms was 4.5 +/- 1.5 microM . The fate of 14C radioactivity was monitored by measuring the radioactivity of the sediment, water, macro- and microorganism, and atmospheric compartments . Radioactivity in the water disappeared quickly from the microcosms, most likely as {14C}dichloromethane (t1/2 = 5.31 +/- 0.41 days) . At the end of the experiments, radioactivity was mainly located in the atmosphere, with traces remaining in the biomass . Under static conditions, the bioaccumulation of 14C radioactivity from the radiolabeled dichloromethane was negligible.

Biochem Biophys Res Commun, 1994 May 30, 201(1), 478 - 85
Molecular cloning and nucleotide sequence of complementary DNA for human hepatic cytosolic acetoacetyl-coenzyme A thiolase; Song XQ et al.; Complementary DNA for human cytosolic acetoacetyl-CoA thiolase (CT) was cloned with the use of anti-{human CT} antibody . The human CT cDNA clone (HCT10) has a 1479-bp insert and a 1191-base open reading frame encoding 397 amino acid residues . Partial polypeptide sequences from purified human CT were present in the deduced sequence . In vivo expression analysis showed that HCT10 encoded potassium-ion non-activated acetoacetyl-CoA thiolase with no 3-ketooctanoyl-CoA thiolase activity, which is characteristic for CT . The deduced amino acid sequence has a 34-57% homology with 4 other human thiolases and 4 acetoacetyl-CoA thiolases of microorganisms.

Schweiz Rundsch Med Prax, 1994 May 17, 83(20), 609 - 14
{Nucleic probes and PCR: application in the diagnosis of bacterial infections}; Bille J et al.; Probes and amplification systems represent new technologic developments in the domain of clinical microbiology . In spite of their high specificity, simple applicability and high velocity the DNA probes show only little sensitivity especially for the direct detection of microorganisms in clinical samples . This sensitivity lead to the development of DNA-amplification technics . PCR is the most famous of them and the most often used one . Next to the direct detection of microorganisms in clinical samples without culture these technics also allow the direct isolation of bacterial toxins, of genes for resistance to antibiotics as well as a systematic search for pathogens in diseases with unknown cause . Different problems of these methods in daily clinical practice are illustrated by four applications 1 . direct detection of mycobacterium tuberculosis complex (M . tbc) in clinical samples, 2 . rapid identification of mycobacterial species, 3 . their typing for epidemiologic intentions, 4 . rapid detection of resistance to antibiotics.

J Biol Chem, 1994 May 6, 269(18), 13405 - 13
Isolation of a cDNA encoding chloroplast ferrochelatase from Arabidopsis thaliana by functional complementation of a yeast mutant; Smith AG et al.; Ferrochelatase catalyzes the insertion of ferrous iron into protoporphyrin IX to form protoheme . It is located in the mitochondria in all eukaryotes and is also found in plastids in plants . Although it has been purified from animals and microorganisms, and genes for it isolated and characterized, very little is known about plant ferrochelatases . We have isolated a cDNA for ferrochelatase from the higher plant Arabidopsis thaliana by functional complementation of a mutant of Saccharomyces cerevisiae defective in this enzyme . The cDNA encodes a protein of 52 kDa, which has 25-35% sequence similarity to ferrochelatases from other organisms . There is an N-terminal extension of about 65 residues, which is almost certainly the chloroplast transit peptide, since the precursor protein, transcribed and translated in vitro, is efficiently imported and processed to the mature size by isolated pea chloroplasts . In contrast, the precursor was not processed by mitochondrial processing peptidase activity, nor could import into isolated yeast mitochondria be demonstrated conclusively, although, presumably, in the rescued yeast mutant, at least some of the Arabidopsis ferrochelatase must be present in the mitochondria . A single transcript the same size as the cDNA was detected in both Arabidopsis leaves and roots, although the amount of message was greater in the photosynthetic tissue . Southern analysis suggests that there is a single gene for chloroplast ferrochelatase in Arabidopsis.

Cas Lek Cesk, 1994 May 2, 133(9), 275 - 6
{Immunologic factors in human colostrum and milk}; Ulcova-Gallova Z et al.; BACKGROUND . The mammary gland is at present conceived as an immunological secretory organ, capable of producing specific and non-specific factors transmitted into colostrum or milk . METHODS AND RESULTS . Colostrum was collected from the 1st to 3rd day after delivery, milk on the 4th to 19th day after delivery . Colostrum from 42 and milk from 63 mothers was examined . Levels of the following were assessed: IgG, IgM, IgD, IgA, sIgA, SCIgA, C3, C4, orosomucoid, prealbumin, alpha 1-antitrypsin, alpha 1-fetoprotein, alpha 2-macroglobulin, haemopexin, haptoglobin, beta 2-microglobulin, alpha 2-AP glycoprotein (methodradial immunodiffusion) and IgE (ELISA) . Colostrum contains more IgG, SCIgA, almost three times more IgM, IgA and secretory IgA than milk . IgD was not detected . Factors of non-specific immunity were found only in low concentrations . CONCLUSIONS . Human colostrum and milk are from the immunological aspect an important liquid with proven bacteriostatic and inhibitory activity preventing penetration of pathogenic microorganisms and absorption of potential allergens into the digestive and respiratory tract of the neonate . From the immunological aspect it is essential to promote breastfeeding.

Chest, 1994 May, 105(5), 1338 - 41
Pleural tuberculosis and HIV infection; Relkin F et al.; Human immunodeficiency virus infection changes the clinical presentation of tuberculosis infection with atypical radiographs and more common extra-pulmonary involvement . We retrospectively studied pleural tuberculosis in HIV-positive patients over a 5-year period . We identified 70 patients with pleural tuberculosis by positive Mycobacterium tuberculosis cultures of pleural fluid and/or pleural tissue, including 43 HIV-positive and 27 HIV-negative patients . The HIV-positive patients were significantly younger (mean age, 38 +/- 1 years in HIV-positive vs 52 +/- 3 years in HIV-negative patients, p < 0.05) . There were more intravenous drug abusers in the HIV-positive group (74 vs 30 percent, p < 0.01) . The HIV-positive group had significantly fewer positive tuberculin skin tests (41 percent vs 76 percent, p < 0.03) . Both groups had similar pleural fluid cellularity and pleural biopsy histologic conditions, but the HIV-positive patients demonstrated significantly more acid-fast bacteria identifiable in pleural tissue (69 percent vs 21 percent, p < 0.01), and a higher incidence of positive M tuberculosis cultures of sputum (53 percent vs 23 percent, p = 0.02) . Pleural tuberculosis in HIV-positive patients presented more often as a manifestation of a greater burden of microorganisms and impaired host response.

J Nutr, 1994 May, 124(5), 694 - 701
Conjugated linoleic acid (9,11- and 10,12-octadecadienoic acid) is produced in conventional but not germ-free rats fed linoleic acid; Chin SF et al.; Conjugated linoleic acid (CLA) is an anticarcinogen in several model animal systems . Conjugated linoleic acid occurs naturally in food and is present at higher concentrations in products from ruminant animals . Given that certain rumen microorganisms produce CLA from free linoleic acid, we studied the effect of feeding free or esterified linoleic acid on tissue CLA concentrations using conventional and germ-free rats . Conventional rats were fed a 5% (wt/wt) corn oil control diet alone or supplemented with 5% free linoleic acid or 8.63% corn oil (equivalent to 5% linoleic acid in triglyceride) . Germ-free rats were fed autoclavable nonpurified diet alone or supplemented with 5% free linoleic acid . Analyses of CLA concentrations were performed on lipids extracted from liver, lung, kidney, skeletal muscle and abdominal adipose tissue, and on liver phospholipid and neutral lipid fractions . Tissue CLA concentrations were higher in conventional rats fed free linoleic acid (the major isomers were cis-9, trans-11 and trans-9, cis-11) than in control animals . Conjugated linoleic acid concentrations in free linoleic acid-fed rats were maximal at 4 wk, and levels were 5-10 times higher than those of controls . Elevated CLA concentrations were also observed in liver phospholipid and neutral lipid fractions . In contrast, CLA concentrations in the tissues of germ-free rats were not affected by diet . Feeding the corn oil-fortified diet to conventional rats did not increase CLA concentration in the tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunol Lett, 1994 May, 40(2), 139 - 46
Killing of Borrelia burgdorferi by macrophages is dependent on oxygen radicals and nitric oxide and can be enhanced by antibodies to outer surface proteins of the spirochete; Modolell M et al.; Interaction of B . burgdorferi organisms with mouse bone marrow-derived macrophages (BMM phi) leads to phagocytosis of microorganisms, induction of nitric oxide (NO) and superoxide radicals (O2-) by BMM phi and killing of spirochetes . Destruction of spirochetes by BMM phi was quantified by a new method based on the release of radioactivity from spirochetes pre-labelled with {3H}adenine . Uptake of B . burgdorferi by BMM phi, which mainly occurs by coiling phagocytosis, generation of NO and O2- radicals as well as killing of spirochetes were significantly enhanced by pre-opsonization of spirochetes with monoclonal antibodies (mAb) to the outer surface proteins A and B but not with those to the periplasmic flagellin . Addition of inhibitors specific for NO and O2- radical synthesis either separately or together to cultures of BMM phi and spirochetes resulted in only partial reduction of the killing potential of effector cells . The data indicate that NO and O2- radicals are necessary, but not sufficient, for complete elimination of B . burgdorferi by macrophages . Together with previous findings that protection against B . burgdorferi infection is conveyed by humoral immune responses the present data indicate that one of the important functions of specific antibodies is their participation in macrophage-mediated control of spirochetes.

Int J Food Microbiol, 1994 May, 22(2-3), 207 - 15
Study of the growth of yeasts from feta cheese; Vivier D et al.; The effects of various physicochemical parameters on the growth of three yeast strains were investigated, including: pH, sodium chloride content, water activity in the medium and temperature . All strains were unaffected by pH changes . Growth was optimal at pH 5.5, while these yeasts were able to develop within the pH 2.5-8 range . Suitable growth was obtained at temperatures of 4 degrees C-44 degrees C and the optimal temperature for growth was 32 degrees C for all three strains . Modelling of this latter parameter is described . Growth of microorganisms was considerably modified by increased NaCl or decreased water activity in the medium.

J Pharm Sci, 1994 May, 83(5), 668 - 73
Derivation of a rigorous equation for the calculation of the F-value in isothermal sterilization processes; Armenante PM; The use of simplified equations utilizing the Z- and F-values to calculate the level of sterilization achieved in isothermal processes is very common in industry . This method assumes that the Z-value is independent of temperature . This is a simplifying assumption that is not based on a physically realistic microbial inactivation model . In the present work the appropriate equations for the Z- and F-values were derived with kinetic theory and utilized to predict the level of sterility obtained during isothermal sterilization . The F-value obtained with the proposed equation was always higher than the F-value obtained when the simplifying assumption was made . Therefore, the use of the equation proposed here for the F-value results in more realistic and generous estimates of the lethal effect on microorganisms produced by isothermal sterilization processes . Tables of the F-values so obtained are provided.

Mol Gen Mikrobiol Virusol, 1994 May-Jun, (3), 39 - 40
{Isolation and molecular-genetic characteristic of a cryptic plasmid from the Francisella novicida like F6168 strain}; Pavlov VM et al.; A 4 Kb plasmid DNA has been isolated from Francisella novicida like strain F6168 . Restriction map of the plasmid was constructed for restriction endonucleases HindIII, XbaI, EcoRV, BgIII . The plasmid pFN10 has been shown to be stably inherited by F . tularensis . The use of pFN10 for the construction of plasmid vectors for microorganisms of the genus Francisella is discussed.

J Anim Sci, 1994 May, 72(5), 1335 - 43
Improved techniques for dissociating particle-associated mixed ruminal microorganisms from ruminal digesta solids; Whitehouse NL et al.; Combinations of physical and chemical methods were evaluated for their ability to remove particle-associated microorganisms (PAM) from saline-washed ruminal digesta solids (SWRDS) . Physical methods included chilling and storage, homogenization, multiple extraction, and agitation with marbles . Chemical methods included use of low pH, Tween 80, formaldehyde, methanol, tertiary butanol, and methylcellulose . Microbial removal from SWRDS was determined directly by using epifluorescence microscopy and indirectly by measuring removal of diaminopimelic acid and total purines . Different combinations of methods resulted in removals of 46 to 82% for particle-associated bacteria (PAB), 52 to 98% for particle-associated protozoa (PAP), and 60 to 83% for PAB plus PAP . Two methods were considered most effective, based on microscopy; both removed similar amounts of PAB (79 to 82%) and PAB plus PAP (80 to 83%) . In one method, SWRDS were stored for 24 h at 4 degrees C in a solution of pH 2 saline, .1% Tween 80, 1.0% methanol, and 1.0% tertiary butanol . In the other method, SWRDS were incubated for 30 min in .1% methylcellulose before storage for 24 h at 4 degrees C in pH 2 saline, .1% Tween 80, and 1.0% methanol . Common to both treatments was subsequent homogenization of the suspensions for 15 s followed by washing the digesta solids seven times with the treatment solutions . Both methods resulted in values that exceeded those reported previously for removal of PAM from ruminal digesta solids.

Rev Esp Enferm Dig, 1994 May, 85(5), 325 - 30
{Functional dyspepsia, gastric emptying of solids, and Helicobacter pylori infection}; Mones Xiol J et al.; The origin of functional dyspepsia (FD) is unknown, however, abnormal gastric emptying and infection by H . pylori have been suggested as possible causes . OBJECTIVE: The aim of this study was to test the hypothesis that infection by H . pylori could be related to alterations in gastric emptying of solids and play a role in the pathophysiology of dyspepsia . METHODS: Studies were performed on 12 controls: 6 males, 6 females, age 40 +/- 13, and on 45 FD patients: 15 males and 30 females, age 43.5 +/- 12 . Clinical criteria for FD diagnosis were post-prandial epigastric pain, nausea, vomiting or epigastric bloating, with normal blood test, upper endoscopy and abdominal ultrasound . Diagnosis of H . pylori infection was either by growth positive on culture of antral biopsy or by all of the following: on Gram stain, urease test positive and visualization of microorganisms in the antral biopsy . Gastric emptying of solids was studied with a radio-nuclide technique . Patients were prospectively classified in 4 groups according to the main symptom: reflux-like, ulcer-like, dysmotility, and non-specific . RESULTS: H . pylori infection was observed in 21/32 (66%) FD patients . No significant differences in the gastric emptying of solids between the control group and patients with FD (tl/2 80 +/- 17 minutes vs 75 +/- 16 min) . The presence of H . pylori infection did not influence gastric emptying rates (78 +/- 16 minutes in infected patients vs 73 +/- 15 min in non infected patients) . Gastric emptying times were similar among the four subgroups of FD patients . CONCLUSIONS: No significant differences in gastric emptying of solids were found in H . pylori infected persons as compared with the controls . These findings suggest that H . pylori infection and/or changes in gastric emptying of solids do not play a role in the pathophysiology of FD.

J Periodontol, 1994 May, 65(5 Suppl), 498 - 510
Bacteria as risk markers for periodontitis; Wolff L et al.; Specific microbial species have been closely associated with periodontitis . Through longitudinal studies, some of these microbial species have been implicated in the etiology of progressive periodontal disease . Although putative periodontal pathogens are often isolated from individuals with severe periodontitis, they also frequently inhibit the subgingival environment and are not always associated with advanced disease . In this respect, it is becoming increasingly apparent that there is no single etiology of the various periodontal diseases . Destructive periodontal diseases are the result of environmental, host, and bacterial factors . Microorganisms, however, are essential components of any model for progressive periodontitis . This paper selectively reviews bacteria as risk markers for periodontitis . Attention focuses on bacteria in conjunction with behavioral patterns (oral hygiene habits and smoking) and host response (gingival crevicular fluid substances) as risk markers for periodontitis . Prospective studies implicating specific bacteria in progressive periodontitis are addressed and a bacterial risk assessment model for progressive periodontitis is discussed with respect to the interplay between bacterial, environmental, and host markers.

Neurol Clin, 1994 May, 12(2), 273 - 84
Acquired myasthenia gravis . Immunopathology; Richman DP et al.; Much of the remarkable advance in our understanding of the immunopathology of MG relates to the availability of two gifts of nature that permit the ready purification of the antigen, AChR . Immunization of experimental animals with AChR has led to the development of the extremely faithful animal model, EAMG . Analysis of both EAMG and MG has revealed that the effector agents in this autoimmune disease are anti-AChR antibodies, whose production is regulated by anti-AChR CD4+ T cells . The pathogenic effects on neuromuscular transmission are mediated by antibody-induced antigenic modulation of end-plate AChR, end-plate membrane destruction through complement fixation and recruitment of inflammatory cells, and antibody-induced blockade of the function of the remaining AChR molecules . The origin of MG remains unknown . One theory proposes that dysregulation of the thymic control of tolerance plays an important role . An alternative hypothesis is that tolerance is broken as the result of a vigorous immune response directed against an invading microorganism that expresses a molecule that is similar to AChR, so-called molecular mimicry . This "normal" response eventually cross-reacts with self-AChR, resulting in the autoimmune damage . Our current knowledge of MG has suggested a number of possible sites of therapeutic intervention that are under active study . Future information concerning the origin of the disease will likely be useful in the design of more effective treatment for this and other related autoimmune diseases.

Isr J Med Sci, 1994 May-Jun, 30(5-6), 443 - 7
Human papillomaviruses and the diagnosis of genital microorganisms; Mitrani-Rosenbaum S; Considerable evidence points to certain types of human papillomaviruses (HPV) as high risk factors in the malignant progression mechanism in lesions of the lower genital tract . Since infection of the genital mucosa by papillomaviruses includes a wide variety of viral types, it is essential to recognize the specific HPV type eventually present in a genital lesion to ensure an appropriate follow-up of the patient . We have developed a polymerase chain reaction (PCR) based assay which differentiates in a single amplification reaction the "malignant" HPV genital types from the "benign" ones . We report also the use of PCR for the detection of other frequent sexually transmitted agents, such as herpes simplex virus and Chlamydia trachomatis . We show that it is possible to design and use a PCR-based assay for the simultaneous detection of various genital agents from a single genital swab . This assay can be a model for the development of additional multidetection systems of microorganisms potentially involved in similar pathologies.

Recenti Prog Med, 1994 May, 85(5), 296 - 302
{Infections due to hard-to-treat germs . Endocarditis and nosocomial opportunistic infections}; Altucci P et al.; The authors describe some aspects of "difficult to treat" infections, pointing out, on the basis of their experience, infective endocarditis (IE) and nosocomial infections in compromised host . Among difficult-to-treat IE, the authors stress: 1) the peculiar etio-epidemiological features and the frequent causative pathogens multiresistance on early post-surgical IE; 2) the problems in detecting and management of IE by HACEK group microorganisms; 3) the problems related to other unusual agents IE, with particular regard to nutritionally deficient variants of S . viridans and to Coxiella burnetii . Among nosocomial infections in compromised host, Authors underline the relationship between either nosocomial flora or surgical/instrumental practices and possible underlying immunodeficiencies . Clinical and diagnostic remarks of sepsis, pneumonitis, meningitis, enteritis in neutropenic patients are then stressed, pointing out their atypical presentations and severe prognosis.

Anal Chem, 1994 May 1, 66(9), 1462 - 7
Use of Saccharomyces cerevisiae in flow injection atomic absorption spectrometry for trace metal preconcentration; Maquieira A et al.; The yeast Saccharomyces cerevisiae was covalently immobilized on controlled pore glass (CPG) using a modified method of enzyme immobilization . This species was packed in a mini-column and incorporated in a flow injection manifold system for trace determination of some metals prior to quantification with atomic absorption spectrometry (AAS) . A number of investigations on the ability of the microorganism to remove metal ions from solution have shown that different metal ions bind to the cell wall of yeast . We have observed that the pH-dependence behavior is different for Pb(II) and Fe(III) compared to the other metal ions . Between pH 6.0 and 7.5 a variety of metal ions bind strongly to the cell surface . All the metal ions tested were deabsorbed by lowering the pH to < 2.0 . Samples of 5 mL of Cd(II), Zn(II), Cu(II), Pb(II), and Fe(III) were preconcentrated to give detection limits of 0.2, 0.1, 0.7, 8.0, and 0.6 ng/mL, respectively . The analysis of real sample reference material showed a good agreement with the certified values for cadmium and copper.

Pol J Pharmacol, 1994 May-Jun, 46(3), 103 - 14
Some biochemical and pharmacological aspects of free radical-mediated tissue damage; Ignatowicz E et al.; Living in aerobic conditions carries a risk of oxidative stress, in connection with free radical deleterious action on tissues and cells . Free radical mechanisms have been implicated in the pathogenesis of many diseases, as well as in host defense against various invading microorganisms . A substantial body of evidence has been reported on free radical involvement in inflammation, ischaemia/reperfusion injury, atherosclerosis and many other pathologies . The aim of this paper is to review selected literature and opinions concerning free radical-induced damage to tissues and to present xenobiotic contribution to oxidative stress.

Tsitol Genet, 1994 May-Jun, 28(3), 3 - 17
{The antimutagenic and gene-protective properties of preparations of plant origin}; Bariliak IR et al.; The data of experimental studies of gene protective and antimutagenic activities of plant extracts on different test systems is reviewed . The most frequently used test systems are microorganisms and experimental animals (49.4 and 40.6% of cases, respectively) . Plant test systems, insects and human cell cultures are rarely used (7.2, 2.9, and 4.3, respectively) . Antimutagenic properties of plant preparations are due to vitamins, pigments, polyphenol complex, coumarin, flavonoids, terpenic saponins, lactons etc.

J Biochem (Tokyo), 1994 May, 115(5), 811 - 3
Characterization of ascorbate oxidase from Acremonium sp . HI-25; Hirose J et al.; The ascorbate oxidase obtained from a microorganism, Acremonium sp . HI-25 (molecular weight, 80 kDa; monomeric protein), was studied with respect to atomic absorption, EPR, absorption spectra, circular dichroism (CD) spectra, and steady-state kinetics . The enzyme was found to be a multicopper protein, containing four copper atoms of three kinds, types 1, 2, and 3 copper, in the ratio of 1:1:2 . The EPR parameters of the type 1 and 2 copper atoms in the ascorbate oxidase are very similar to those in the case of the ascorbate oxidase obtained from cucumber, which is a dimeric protein . The apparent Km and kcat values for ascorbic acid of the ascorbate oxidase from Acremonium sp . HI-25 are almost the same as those of the monomeric unit of the ascorbate oxidase from cucumber.

J Biolumin Chemilumin, 1994 May-Jun, 9(3), 139 - 44
Applications of low-light imaging to life sciences; Nicolas JC; Photon imaging is a new technique for the quantitative analysis of bioluminescence and chemiluminescence and can be performed both at the macro and micro levels . The high sensitivity and spatial resolution of photon-counting cameras have resulted in the development of new applications in the life sciences . At the macro level, imaging is a valuable tool for the rapid identification of biological samples emitting long-lasting glows in assays using microtitre plates or filter formats (immunoassays, DNA probes, phagocytosis, gene expression, metabolite and drug analysis) and also for in vivo studies of promoter activity . At the micro level, low-light imaging can be used for analysing multiple analytes on micro sensors) and for advanced cell analysis (immunocytology, in situ hybridization, identification of cells or tissues expressing the luciferase gene, intracellular or intercellular protein traffic, metabolite analysis and imaging of Ca2+ flux and phosphorylation reactions) . Two-dimensional photon-counting instrumentation is a versatile and powerful research tool for imaging and is complementary to conventional luminometers . The main applications to the life sciences involve many types of luminescence assays and can be performed on multiple samples in standard and non-standard formats . Photon-counting coupled to imaging is very helpful in selecting microorganisms or cells expressing bioluminescent genes . Measurements can be made in vitro and in vivo with a sensitivity comparable to that of phototube luminometers.

Med Hypotheses, 1994 May, 42(5), 313 - 7
A specific oxidant is the prime factor in cancer cells' origin and growth; White MW; Sufficient evidence is present to conclude the fact that there is a specific anion acceptor (oxidant) substance actively functioning within the living malignant cell . It is this oxidant that possesses the physiological properties to accept the negative charged electrons while releasing or expelling the oxygen molecules . This oxidant, as studies indicate, consists of a specific delicate chemical entity . It arises from one of several varieties of plant like bacterial microorganisms, whose spores, once formed, have the genetic capability of embedding within a cell or sac, lie quiescently, while retaining, and still holding viable its electron acceptor chemical complex . These spores are identified in the group of microorganisms known as ascospores . It is important to emphasize that it is the spore forms only and not the adult form in any manner that enters the animal cell . It is this oxidant present within the latter spores that will become activated when there develops an adequate circulating flow of blood to provide the transportation of the metabolites, electrons, cations, CO2 and oxygen molecules to and from the involved cells . The ultimate response, with this oxidant's presence is the striking physiological alteration whereby respiration and metabolism is henceforth basically anaerobic . There is likewise the ability too for the spores under these circumstances to reproduce asexually to produce further spores by the method of abstriction from the blastospore's embryonic phase.

Int J Immunopharmacol, 1994 May-Jun, 16(5-6), 475 - 80
Antitumoral activity of an immunomodulatory fraction of Nocardia opaca: mechanism of action; Leibovici J et al.; Immunomodulatory substances have been used as antineoplastic agents in experimental and human systems . Many of these agents were derived from microorganisms . Several biologically active fractions have been isolated from Nocardia . These derivatives were shown to induce interferon production, to activate natural killer cells and macrophages and to exert an antitumoral effect . We attempted to examine the mechanism of the antitumoral activity of the Nocardia water-soluble mitogen (NWSM) . The tumor tested was the Lewis lung carcinoma (3LL) . Regular histological examination and identification of the cellular immune reaction by monoclonal antibodies against macrophages (Mac 1 antigen), B- (IgG expressing) and T-lymphocytes (anti-Lyt-1), analysed by flow cytometry, were performed on samples of the tumor site and of the spleen . Intratumoral administration of the immunomodulators resulted in a massive accumulation of inflammatory cells around the tumor in mice treated with NWSM . The thick rim of infiltrating cells consisted of macrophages and lymphocytes, while the nontreated tumor was found to provoke only a scanty lymphocyte infiltration . Macrophages were, therefore, present at the tumor site and were directly implicated in the antitumoral effect of the Nocardia immunomodulator . T-lymphocytes were also observed at the site of the tumor . The spleen reaction consisted of marked extramedullary hematopoiesis and enlarged follicles containing prominent germinal centres (assessed also by a FACS-demonstrated increase in B-lymphocytes) . In view of the inefficiency of chemotherapy in the treatment of advanced cancer, it is of major importance to explore alternative cancer treatment modalities . Immunotherapy is a particularly interesting alternative since it can potentially affect metastatic disease.

Science, 1994 Apr 22, 264(5158), 566 - 9
{URE3} as an altered URE2 protein: evidence for a prion analog in Saccharomyces cerevisiae; Wickner RB; A cytoplasmically inherited element, {URE3}, allows yeast to use ureidosuccinate in the presence of ammonium ion . Chromosomal mutations in the URE2 gene produce the same phenotype . {URE3} depends for its propagation on the URE2 product (Ure2p), a negative regulator of enzymes of nitrogen metabolism . Saccharomyces cerevisiae strains cured of {URE3} with guanidium chloride were shown to return to the {URE3}-carrying state without its introduction from other cells . Overproduction of Ure2p increased the frequency with which a strain became {URE3} by 100-fold . In analogy to mammalian prions, {URE3} may be an altered form of Ure2p that is inactive for its normal function but can convert normal Ure2p to the altered form . The genetic evidence presented here suggests that protein-based inheritance, involving a protein unrelated to the mammalian prion protein, can occur in a microorganism.

Biochim Biophys Acta, 1994 Apr 20, 1191(1), 103 - 8
Reversal of doxorubicin resistance and catalytic neutralization of lysosomes by a lipophilic imidazole; Dubowchik GM et al.; A number of lipophilic nitrogenous bases, designed to act as membrane-active, catalytic proton transfer agents, were tested for their ability to neutralize the acidity of lysosomes, a model for other acidic intracellular vesicles involved in drug sorting . The most successful of these, an imidazole 1, caused a 1.7 unit rise in lysosomal pH of RAW cells at 100 microM, compared to a 0.2 and 1.4 unit rise for ammonium chloride at 100 microM and 10 mM, respectively . Compound 1 also exhibited potent reversal of doxorubicin (DOX) resistance in the HCT116-VM46 cell line by a factor of 14 over the sensitive strain, and superior to that of widely used verapamil (VRP) by a factor of 1.75 at 20 microM . It also has antiviral properties, and potential applications in other lysosome-related areas such as immunotoxin potentiation and the control of bacterial toxins, immune response, prion replication, malaria and intralysosomal microorganisms.

MMWR Recomm Rep, 1994 Apr 15, 43(RR-5), 1 - 18
Addressing emerging infectious disease threats: a prevention strategy for the United States . Executive summary; Adhesion of hard spheres under the influence of double-layer et al.; Institut National de la Sante et de la Reberche Medicale, Contrat Jeune Formation 92-04, Universite Louis Pasteur, Strasbourg, FranceThe deposition process of colloidal particles or microorganisms on flat surfaces is analyzed by means of computer simulations . Interparticle interactions (double layer and van der Waals) and weak gravitational forces are taken into account; hydrodynamic interactions, on the other hand, are neglected . In particular, the deposition probability as a function of the deposition location of a particle in the presence of one or two identical fixed particles is discussed . It is shown, in particular, that the ratio of the adhesion probabilities at a given location r, for particles subject to weak gravitation, in the presence and in the absence of the interparticle interaction U(r) follows approximately a Boltzmann law exp{-U(r)/kT}, even though the adsorption process is fully irreversible . This result validates, as far as the distribution function of particles on a surface is concerned, Adamczyk's assumption {Adamczyk, Z., Zembala, M., Siwek, B . & Warszynski, P . (1990) J . Colloid Interface Sci . 140, 123-137} that the adhesion process of Brownian particles can be modeled by a random sequential adsorption model with an adsorption probability equal to exp{-U(r)/kT}.

Gene, 1994 Apr 8, 141(1), 39 - 46
Cloning and sequences of two macrolide-resistance-encoding genes from mycinamicin-producing Micromonospora griseorubida; Inouye M et al.; Two macrolide-resistance determinants were cloned from a mycinamicin (Mm)-producing Micromonospora griseorubida strain in Streptomyces lividans and Streptomyces parvulus . One of the cloned genes, designated myrA, was cloned as a gene which conferred strong resistance to Mm and tylosin (Ty), but not to erythromycin (Er) or josamycin (Jm) on S . lividans . Another gene, named myrB, was cloned as an ErR-encoding gene which conferred MLS resistance (to macrolide, lincosamide and streptogramine B antibiotics) on S . parvulus . Both myrA and myrB were sequenced and the corresponding ORFs were determined . The deduced amino acid (aa) sequence of myrA showed no similarity to proteins in the available databases, suggesting that an unknown mechanism of macrolide resistance is exerted by the MyrA protein . The deduced aa sequence of myrB exhibited high similarity to 23S rRNA methyltransferases (MTases), such as ErmE and CarB, from a variety of microorganisms.

Biochemistry, 1994 Apr 5, 33(13), 4080 - 5
Adaptation to altered growth temperatures in Acholeplasma laidlawii B: Fourier transform infrared studies of acyl chain conformational order in live cells; Moore DJ et al.; Acholeplasma laidlawii B cells, highly enriched in saturated C14 and C15 fatty acids, have been grown at several temperatures . Conformational order in the acyl chains of live cell membranes has been monitored with Fourier-transform infrared (FT-IR) spectroscopy . Coupled CH2 wagging progressions, characteristic of the all-trans conformation, have been used to quantitatively monitor the extent of trans-gauche isomerization . A simple model relating the changes in the progression intensity to the introduction of gauche rotamers into the acyl chains suggest that at the growth temperature (25 or 37 degrees C for the C14-enriched cells, 30 or 37 degrees C for the C15-enriched cells) the cell membrane contains about 1.5 gauche bonds per acyl chain . The thermotropic response of the CH2 stretching frequencies near 2850 cm-1 reveals that the gel-liquid-crystal phase transition is shifted toward lower temperatures when the growth temperature is reduced . In addition, at any given temperature, the cells grown at lower temperature are more conformationally disordered than their counterparts grown at higher temperature . This behavior is consistent with the quantitative results from the CH2 wagging measurements . The data reveal that A . laidlawii B cells can control the overall conformational state of their membranes and that the observed degree of disorder (1.5 +/- 0.3 gauche bonds/acyl chain), when achievable, provides optimum cell viability . The ability of this microorganism to control the degree of membrane disorder delineates one possible pathway for homeoviscous adaptation.

Community Dent Oral Epidemiol, 1994 Apr, 22(2), 116 - 21
Early-onset periodontitis in Hispanic-American adolescents associated with A . actinomycetemcomitans; Cappelli DP et al.; This study examines the frequency of oral disease in an adolescent population, and assesses the relationship to Actinobacillus actinomycetemcomitans . A total of 470 eighth grade students from San Antonio, Texas, were examined clinically for number of teeth, frequency of gingival inflammation, frequency of sites with BOP, and frequency of sites with 3-5 mm pockets, and pockets > 5 mm . The population ranged in age from 12 to 17 yr and was 93% Hispanic . Heavy accumulations of plaque and calculus were frequently observed and were associated with gingival inflammation, as 95.6% of the students exhibited bleeding on probing, and 99.6% of the students presented with at least on quadrant of inflammation upon visual examination . Significantly, 25.7% of the students exhibited early-onset periodontitis (EOP) with 1.7% diagnosed as LJP . Many students exhibited substantial levels of plaque and calculus, but no clinical evidence of loss of attachment . Subjects with periodontitis (EOP or LJP) presented with elevated systemic IgG antibody to A . actinomycetemcomitans serotype b and subgingival plaque samples positive for the microorganism . These results describe the prevalence of EOP/LJP in an adolescent Hispanic population from South Texas . The findings support that A . actinomycetemcomitans may represent a pathogen in periodontitis and while oral health care may be poor, contact with the microorganism appears to be required to initiate disease in this population.

Oftalmologia, 1994 Apr-Jun, 38(2), 101 - 6
{The corneal epithelial barrier}; Apostol S et al.; The corneal epithelium is an stratificated pavimentous epithelium . The epithelial cells are grouped in 3 levels: superficial cells, intermediate cells, basal cells . The superficial cells are solidarised by there type of junctional complexes: desmosomes, impermeable junctions, and communicating junctions . Because the corneoconjunctival surface is colonised by microorganisms and every minimal lesions can favorise an infection, the epithelial integrity plays a protective role . The corneal epithelium constitute the main way of intraocular penetration of topical drugs . There are two ways of drugs penetration through corneal epithelium: intracell and pericell way . The penetration speed was influenced by ocular factors (epithelial lesions) and drugs features (solubility, molecular mass, molecular structure, pH, pK, concentration, contact time).

Am J Obstet Gynecol, 1994 Apr, 170(4), 1048 - 59; discussion 1059-60
Bacterial vaginosis is associated with prematurity and vaginal fluid mucinase and sialidase: results of a controlled trial of topical clindamycin cream; McGregor JA et al.; OBJECTIVE: The pathogenesis of preterm birth and other adverse pregnancy outcomes linked with reproductive tract infection remains poorly understood . Mucolytic enzymes, including mucinases and sialidases (neuraminidase), are recognized virulence factors among enteropathogens and bacteria that cause periodontal infection . Perturbation of maternal cervicovaginal mucosa membrane host defenses by such enzyme-producing microorganisms may increase the risk of subclinical intrauterine infection during pregnancy and thus increase risks of preterm birth . STUDY DESIGN: We prospectively evaluated vaginal fluid mucinase and sialidase and selected cervicovaginal bacteria along with pregnancy outcomes in 271 women . Within this study, women with bacterial vaginosis (16 to 27 week' gestation) were treated with 2% clinadmycin vaginal cream or placebo . Enzyme, microbial findings, treatment effects, and pregnancy outcomes were compared among drug- and placebo-treated women and control women without bacterial vaginosis . RESULTS: Presence of bacterial vaginosis at intake was associated with increased risk of preterm birth (relative risk 3.3, 95% confidence interval 1.2 to 9.1, p = 0.02), premature rupture of membranes (relative risk 3.8, 95% confidence interval 1.6 to 9.0, p = 0.002), and preterm premature rupture of membranes . Mucinase and sialidase activities were more commonly identified, and they occurred in higher concentrations, if present, in women with bacterial vaginosis (mucinase: 44.3% with bacterial vaginosis vs 27.4% without, p = 0.007; sialidase: 45% with bacterial vaginosis vs 12% without p < 0.001) . Sialidase activity was associated with bacterial vaginosis-linked organisms (Gardnerella vaginalis, Mobiluncus spp, and Mycoplasma hominis) and Chlamydia trachomatis and yeast species; mucinase activity was associated only with bacterial vaginosis-linked microorganisms . Clindamycin, 2% cream, was effective treatment for bacterial vaginosis and temporarily reduced mucinase and sialidase activities . Topical treatment of bacterial vaginosis did not reduce risks of perinatal morbidity . Women with persistent or recurrent sialidase 8 weeks after treatment were at increased risk of preterm birth (15.6% vs 7.4%) premature rupture of membranes (30% vs 15%), and low birth weight (20% vs 3%, relative risk 6.8, 95% confidence interval 1.6 to 28.1) . CONCLUSIONS: Persistence of sialidase-producing vaginal microorganisms in numbers sufficient to increase vaginal fluid sialidase activity may be a risk factor for possibly preventable subclinical intrauterine infection and preterm birth . This study confirms and further informs our understanding of the association of bacterial vaginosis and preterm birth; studies to evaluate whether systemic treatment for bacterial vaginosis can effectively reduce vaginal mucolytic enzymes and risks of prematurity and other morbid outcomes are continuing.

J Trauma, 1994 Apr, 36(4), 482 - 5
The role of systemic antibodies against intestinal Escherichia coli in the prevention of bacterial translocation of Escherichia coli in a burn model in mice; Dijkstra HM et al.; Bacterial translocation (BT) from the gastrointestinal (GI) tract has been proposed to play a role in the pathogenesis of septic complications in severely burned patients . It is well known that severely ill patients such as thermally injured patients may acquire new potential pathogenic microorganisms in the GI tract . Because these patients have no antibodies directed against these acquired microorganisms, BT may be facilitated in these patients . To investigate this hypothesis in a burn model, a study was performed in which two groups of C3H-HeN mice underwent a different period of intestinal overgrowth by a single neomycin-resistant (NR) Escherichia coli strain after oral neomycin-bacitracin treatment . Group I underwent a short period (5 days) and group II experienced a long period (44 days) of intestinal overgrowth before a thermal injury was executed . Two days postburn, plasma antibody titers of IgA, IgG, and IgM isotype against NR E . coli were measured by indirect immunofluorescence (IIF) and BT to various organs was determined by culturing . Although there were no significant differences of BT to organs between the groups, the IgG antibody titer against the NR E . coli strain was significantly increased in group II . Antibody titers of IgA and IgM were not significantly different between the groups . Titers of plasma antibodies of IgG isotype against the intestinal NR E . coli did not correlate with BT . We conclude that increased IgG titers against the NR E . coli used are the result of a longer intestinal overgrowth period and are not associated with prevented or decreased BT.

J Pediatr, 1994 Apr, 124(4), 566 - 73
Immunoglobulin A subclasses in infants' saliva and in saliva and milk from their mothers; Fitzsimmons SP et al.; We sought to determine (1) the ontogeny of secretory IgA subclasses in saliva of breast- and formula-fed infants and (2) the influence of breast-feeding on the maturation of secretory salivary IgA subclasses . Secretory IgA and subclasses 1 and 2 concentrations were determined in saliva from 40 healthy, term infants from birth to age 18 months, and in parallel milk samples from the infants' mothers who were breast-feeding during the first 6 months after birth . Secretory IgA was detected in the neonates' saliva as early as 3 days after birth, increased rapidly during the next 6 months, but then stabilized at a level approximately one-sixth that of the mothers' salivary secretory IgA . Secretory IgA2 represented less than 15% of secretory IgA in saliva collected 2 weeks after birth but by 6 months represented 24.4% of secretory IgA, a value approaching that of the mothers' salivary secretory IgA2 (30.4%) . This increase in the proportion of secretory IgA2 was temporally related to a reduction in the proportion of secretory IgA2 in milk throughout lactation . The secretory IgA concentration increased more rapidly during the first 6 months after birth in infants exclusively breast fed than in those exclusively bottle fed . We conclude that although secretory immunity is immature in infants, breast-feeding may aid in protection against pathogenic microorganisms by increasing the rate of mucosal IgA maturation.

J Am Coll Surg, 1994 Apr, 178(4), 321 - 5
Single-dose cefuroxime versus multiple-dose cefazolin as prophylactic therapy for high-risk cholecystectomy; Sirinek KR et al.; The ideal regimen for the prevention of postoperative infections occurring after elective cholecystectomy has been widely debated . This double-blind, randomized study was conducted to compare the effectiveness and safety of cefuroxime with that of cefazolin in 295 patients undergoing elective cholecystectomy who were considered to be at high risk for postoperative infection . Patients were randomly assigned to receive either a single 1.5 gram dose of cefuroxime plus three doses of placebo, or four 1 gram doses of cefazolin . Each regimen was begun 30 to 60 minutes preoperatively and repeated every six hours for three doses postoperatively . Patients were evaluated during the hospitalization period and again at 30 days . All postoperative infections, including remote infections, were included in the definition of failure . Bacteriologic success rates were 95.5 percent in the cefuroxime group and 98.2 percent in the cefazolin group (p > 0.05) . Corresponding clinical success rates were 91.4 and 94.9 percent (p > 0.05), respectively . There was no association between intraoperative bile cultures and the risk of failure or the type of microorganism isolated from postoperative infections . Both regimens were well-tolerated . In view of the additional costs and time associated with preparation and administration of multiple doses, a single preoperative 1.5 gram dose of cefuroxime may be a cost-effective alternative to four 1 gram doses of cefazolin in patients undergoing elective cholecystectomy who are at high risk for postoperative infection.

Biometals, 1994 Apr, 7(2), 135 - 41
Evidence for the interference of aluminum with bacterial porphyrin biosynthesis; Scharf R et al.; Aluminum (0.74 mM) was found to retard bacterial growth, and enhance porphyrin formation and excretion in Arthrobacter aurescens RS-2 . Coproporphyrin III was shown to be the main porphyrin excreted by aluminum-exposed A . aurescens RS-2 cultures and by RS-2 cultures grown under anoxic conditions . Synthesis and excretion of porphyrins in A . aurescens RS-2 increased in a dose-dependent manner when the bacteria were exposed to increasing aluminum concentrations . Incubation of A . aurescens RS-2 with delta-aminolevulinic acid (delta-ALA, 1.2 mM) brought about the intense formation and excretion of porphyrins by the cells, in the presence or absence of aluminum . delta-ALA slightly enhanced the toxicity of aluminum towards RS-2 bacteria . Furthermore, the intracellular concentration of heme was reduced by 63.9 +/- 8.67% in aluminum-exposed RS-2 bacteria when compared with control cultures . The results are discussed in light of the recent finding concerning aluminum toxicity and porphyrin biosynthesis in microorganisms.

Am J Respir Crit Care Med, 1994 Apr, 149(4 Pt 1), 860 - 6
Bronchoalveolar lavage for diagnosing bacterial pneumonia in mechanically ventilated patients; Aubas S et al.; To assess the usefulness of BAL in diagnosing bacterial pneumonia in mechanically ventilated patients, 80 BAL fluid samples obtained from 72 patients with lung infiltrates were studied using the following parameters: infected cell count (polymorphonuclear leukocytes or macrophages with intracellular organisms), microscopic examination of stained smears, and quantitative culture with the determination of the simplified bacterial index (SBI) and the predominant species index (PSI) . Of the 80 BAL samples studied, 56 were performed under antibiotic therapy . Bacterial pneumonia was the final diagnosis in 28 cases . The SBI is the sum of the whole numbers of each bacterial concentration expressed as a common logarithm . The PSI is the whole number of the predominant microorganism's concentration expressed as a common logarithm . The discriminative value of each test was assessed using a receiver operating characteristic (ROC) curve, whereby the possibility of establishing a cutoff value used to discriminate between the presence or absence of pneumonia is evaluated . The percentage of infected cells was higher in the pneumonia group (8.8 +/- 18.1 versus 0.4 +/- 1.1%, p < 10(-3), but no cutoff value could be proposed . Under microscopic examination, the presence of bacteria was noted with a significantly greater frequency in the pneumonia group (sensitivity 67.8% and specificity 82.7%) . A total of 58 BAL samples were positive when cultured . The SBI was significantly higher in the pneumonia group (6.5 +/- 2.9 versus 1.6 +/- 1.7, p < 10(-4).(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Respir Cell Mol Biol, 1994 Apr, 10(4), 430 - 6
Lectin-mediated interactions of surfactant protein D with alveolar macrophages; Kuan SF et al.; Surfactant protein D (SP-D) is a calcium-dependent carbohydrate-binding protein that is secreted into the pulmonary airspaces by type II epithelial and Clara cells . Previous studies have shown that SP-D can bind to specific surfactant phospholipids and to glycoconjugates associated with the surface of various microorganisms, consistent with possible roles in surfactant metabolism and pulmonary host defense . We now describe specific saccharide-mediated interactions of SP-D with alveolar macrophages in lung tissue and in vitro . Biotinylated rat SP-D showed specific binding to alveolar macrophages in sections of rat lung; this labeling was inhibited by competing saccharides or EDTA . In addition, the binding of 125I-SP-D to isolated alveolar macrophages in the presence of calcium was time-dependent, saturable, and reversible and was preferentially inhibited by known monosaccharide and disaccharide ligands for SP-D . Scatchard analysis gave an apparent single class of binding sites with a Kd = 1.4 x 10(-6) M . We speculate that the multivalent structure of SP-D mediates bridging interactions between microbial glycoconjugates or surfactant phospholipids and specific glycosylated ligands expressed on the surface of phagocytic cells.

J Vet Diagn Invest, 1994 Apr, 6(2), 188 - 94
A sensitive immunoblotting technique for the serodiagnosis of Brucella ovis infections; Kittelberger R et al.; A simplified electrophoretic immunoblotting technique based on antigen extracted from Brucella ovis cells with sodium dodecyl sulfate/mercaptoethanol was compared with the complement fixation test (CFT), the enzyme-linked immunosorbent assay, and the gel diffusion test . Sera from 89 chronically infected, semen culture-positive rams, 378 sera from B . ovis-infected flocks, 300 sera from accredited disease-free flocks, and 29 sera from specific-pathogen-free sheep were used . The immunoblotting technique had sensitivity and specificity comparable to those of the standard tests and was able to identify several CFT-negative or -borderline sera as positive . The major immunoreactive antigens of B . ovis had molecular masses of 63, 29, 19 kD (proteins) and 8-12 kD (rough lipopolysaccharide) . Antibodies against these antigens were present in 96% of CFT-positive sera from infected flocks and in 100% of sera from semen culture-positive rams . However, immunoblotting also identified antibodies to components other than the major antigens in 1% of CFT-negative sera from infected flocks and in 7.7% of the sera from flocks with a history of freedom from the disease . These reactions probably represent cross-reactivities with other microorganisms and were distinguishable from truly positive reactions.

Boll Chim Farm, 1994 Apr, 133(4), 235 - 8
Microbial and mycotoxic contamination of peppers and food safety; Delcourt A et al.; Twelve random samples of pepper powders were analyzed for contamination by microorganisms of public health significance (bacteria, moulds) and for aflatoxin B1 concentration . Black peppers were more heavily contaminated than white peppers but the most important bacteria causing foodborne diseases were not isolated; The mould flora was dominated by xerophilic species, particularly Aspergillus fumigatus, A . flavus, A . niger and A . ochraceus . These potentially pathogenic species can be dangerous for predisposed patients . The most striking result concerns aflatoxin B1 which was detected in every sample analyzed and could not always be correlated with the occurrence of a mycotoxinogenic strain of Aspergillus, suggesting the use of a sterilizing treatment previously . So, the detection of aflatoxin B1 must be a necessary criterion to be added to microbial criteria to appreciate the quality of peppers.

Clin Microbiol Rev, 1994 Apr, 7(2), 174 - 84
DNA fingerprinting of medically important microorganisms by use of PCR; van Belkum A; Selected segments of any DNA molecule can be amplified exponentially by PCR . This technique provides a powerful tool to detect and identify minimal numbers of microorganisms . PCR is applicable both in diagnosis and in epidemiology . By amplification of hypervariable DNA domains, differences can be detected even among closely related strains . PCR fingerprinting is a valuable tool for medical microbiologists, epidemiologists, and microbial taxonomists . The current state of PCR-mediated genotyping is reviewed, and a comparison with conventional molecular typing methods is included . Because of its speed and versatility, PCR fingerprinting will play an important role in microbial genetics, epidemiology, and systematics.

Enferm Infecc Microbiol Clin, 1994 Apr, 12(4), 200 - 3
{Evaluation of 4 media for the isolation of Helicobacter pylori from gastric biopsies}; Merino FJ et al.; BACKGROUND: Different culture mediums were used for the isolation of Helicobacter pylori . In this study three mediums commonly used for the culture of this microorganism were evaluated: chocolate agar, Martin-Lewis medium and CP of Dent medium as well as a new selective medium Pylori agar . METHODS AND RESULTS: Over a period of 7 months gastric biopsies were collected in 112 patients with clinical manifestations of chronic atrophic gastritis . H . pylori was isolated in some of these mediums on 73 occasions (65.1%) . On 72 of the 73 occasions the microorganism grew in the Pylori agar medium (98.6%) being the medium achieving the greatest number of isolations, followed by the CP of Dent medium with 67 isolations (91.7%), 65 isolations with the Martin-Lewis medium (89.0%) and 57 isolations with chocolate agar (78.0%) . The chocolate agar medium was that which most frequently presented contaminant flora (35 times: 61.4%) and the CP of Dent medium achieved the most rapid and widespread growth . The colonies were largest and therefore easier to recognize in the CP of Dent and Pylori agar mediums . CONCLUSIONS: The authors recommend the association of the CP of Dent and Pylori agar mediums in the isolation of Helicobacter pylori since these two mediums provide the greatest number of isolations with the greatest growth and ease for colony recognition.

J Clin Microbiol, 1994 Apr, 32(4), 893 - 6
Development and evaluation of PCR test for detection of Taylorella equigenitalis; Bleumink-Pluym NM et al.; A PCR for the detection of Taylorella equigenitalis, the causative agent of contagious equine metritis, was developed and evaluated . A genus-specific primer-probe set was derived from the 16S ribosomal DNA sequences . The PCR was specific and amplified a 585-bp product from all 64 available T . equigenitalis isolates . This PCR product hybridized with a specific probe in a dot spot assay . A variety of microorganisms from the genital tracts of horses or with a close phylogenetic relationship to T . equigenitalis did not yield a visible PCR product and were all negative in the dot spot hybridization assay . The results of the PCR assay were compared with those of culture by using 191 genital swabs from horses of several breeds . We demonstrate that the sensitivity of the PCR assay is superior to that of culture . The assay is most sensitive when DNA from culture plates incubated for at least 2 days is used . Of the tested samples, 1.5% were positive in the culture assay, whereas 35% were positive in the culture PCR assay . PCR-positive samples were obtained from all breeds tested . This means that many T . equigenitalis-carrying horses go unidentified by the current culturing technique . This affects current views about the spread and control of T . equigenitalis.

Infusionsther Transfusionsmed, 1994 Apr, 21(2), 104 - 14
{Prevention of infections caused by intravascular catheters--a review of the literature}; Bach A et al.; OBJECTIVE: The literature on catheter-related infections was reviewed to discuss appropriate strategies for the prevention of infections related to intravenous catheters . DATA SOURCES AND SELECTION CRITERIA: The data bases Medline, Biosis and Embase (publication years 1988 to June 1993) were used to retrieve all articles with the key words catheter and infection . Papers covering infections related to intravenous catheters were included . Furthermore, landmark articles from previous years were selected . Only a selected number of articles was listed in the References . RESULTS: Most authors stress the importance of strict aseptic precautions in the management of intravenous lines and the need for dedicated, specialized care of intravascular devices . Quantitative culture of catheter segments and molecular subtyping of microorganisms provide new insights into the pathogenesis and diagnosis of catheter-related infections and enable the evaluation of preventive measures . Technological advances in manufacturing catheter polymers with anti-infective properties will facilitate a reduction in the incidence of catheter-related infections to a greater extent than with any other methods used to date . CONCLUSION: Prevention of catheter-related infections is based on the care of these devices according to strict hygienic standards . In the near future, modification of plastic polymers with anti-infective properties will allow for a further reduction in these infections.

ASAIO J, 1994 Apr-Jun, 40(2), 176 - 80
Prosthetic valve endocarditis . An analysis of the outcome in 32 cases; Otaki M; To evaluated the clinical results and risk factors with prosthetic valve endocarditis (PVE), we reviewed data on 32 patients who were hospitalized over a period of 10 years because of prosthetic valve dysfunctions secondary to endocarditis . The linearized incidence of PVE was 0.89% per patient year . Overall mortality was 34% (11 of 32 patients) . However, the mortality differed depending upon the factors associated with PVE: medical treatment alone (100%, p < 0.001), early onset within 12 months (53%, p < 0.05), and complication with systemic emboli (80%, p < 0.05) . In contrast, anatomic valve position, mechanical valves, female gender, microorganisms, and conduction abnormality did not appear to be significant risk factors . In the 25 patients with medical-surgical therapy, there were 4 operative deaths (16%, 4 of 25 patients) . Pre operative New York Heart Association Class IV (p < 0.05) and reoperations on an urgent basis (p < 0.04) had a significant correlation with the operative mortality . On the basis of these results, the outcome of PVE can be improved if conditions predisposing to myocardial damage or complications leading to deaths are prevented with initial treatment by antibiotics and subsequent surgical intervention.

Rev Latinoam Microbiol, 1994 Apr-Jun, 36(2), 139 - 58
{Synthesis, function, and evolutionary origin of secondary metabolites produced by micro-organisms}; Santana C et al.; The microbial secondary metabolites are compounds with a wide range of chemical structures, produced mainly by actinomycetales and some fungi, usually in the late growth phase . Although a high proportion of this metabolites are antibiotics, there are also examples with pigment, herbicide and surfactant properties . Its function has been correlated to bacterial pathogenicity and cellular differentiation, however, properties dealing with chelation, hormonal and antitumor activities as well as nutritional reserve have been also reported . As in other examples of cellular compounds, the secondary metabolites are produced from low molecular weight precursors . For this purpose, specific biosynthetic pathways are utilized and regulated by processes which generally affect either the activity or the synthesis of the enzymes involved in it . Considering the secondary metabolites apparently are dispensable compounds, there are difficulties to explain their existence from an evolutionary point of view . Explanations to their existence have gone from laboratory artifacts to those conferring them an adaptative value in the past . It seems that they were maintained due to selective advantages to the producer microorganisms and probably, their sometimes complex biosynthetic pathways, have emerged from primary metabolites and evolved later independently by random mutation, amplification and genetic transfer.

Immun Infekt, 1994 Apr, 22(2), 53 - 5
{Intravenous immunoglobulin substitution in patients with ARC and AIDS (WR 3-6)}; Kiehl M et al.; HIV-infected patients acquire a profound dysfunction in humoral and cellular immunity . This immunological impairment causes a markedly increased incidence of recurrent infections . While effective prophylaxis of Pneumocystis carinii pneumonia is available, infections with other microorganisms still cause a high rate of morbidity and mortality . Preliminary results of our randomized outpatient trial to evaluate the efficacy of intravenous immunoglobulin (IVIG) in adults demonstrate that IVIG reduces the episodes of fever, diarrhea, and the duration of hospitalization . We also found a significant reduction of mortality due to infection.

Rev Prat, 1994 Apr 1, 44(7), 855 - 64
{Recognition and identification of unknown infectious agents}; Berche P; The recognition and the identification of previously unrecognized infectious agents require a multidisciplinary approach to specify the nosologic entity of the disease and the epidemiological data, especially the modes of transmission and the risk factors, as well as to discover the microorganism in the laboratory . In the past 20 years, significant breakthroughs have been achieved in cellular cultures (growth factors), in immunology (monoclonal antibodies), and moreover in molecular biology, which have been widely used in the field of infectious diseases . Whereas the classical methods used to grow microorganisms remain of major interest in many cases, innovating strategies have been recently designed to identify previously unknown pathogens . The genomic amplification by polymerase chain reaction (PCR) of highly conserved bacterial genes (as those coding for ribosomal RNA), from tissue biopsies for example, allow to recognize unknown bacteria . The evolutionary distance between a newly recognized pathogen and known microorganisms can be calculated through sequencing of these genes, as described for Rochalimaea henselae or Tropheryma whipplelii . The constitution of cDNA banks from infected tissues is also a novel approach allowing to clone and sequence viral genes, such as those from hepatitis C or from hepatitis E . In the near future, noteworthy improvements will be achieved to rapidly detect microorganisms with highly sensitive and specific tests using monoclonal antibodies, molecular probes (including branched DNA) and with PCR (including Q beta replicase and ligase chain reaction), and to determine the genetic diversity of microbial pathogens by new methods as pulse field gel electrophoresis or arbitrarily primed PCR . This will result in a better knowledge of the pathophysiology of infectious diseases, in a better recognition of a typical, previously unrecognized clinical expression of pathogenicity, and also in a more precise assessment of the actual impact of a given pathogen in human populations by highly sophisticated diagnosis tests.

Mol Biochem Parasitol, 1994 Apr, 64(2), 327 - 36
A short interspersed repetitive element provides a new 3' acceptor site for trans-splicing in certain ribosomal P2 beta protein genes of Trypanosoma cruzi; Vazquez MP et al.; Four Trypanosoma cruzi genomic DNA fragments carrying different TcP2 beta genes have been isolated and sequenced . Three of them had a single TcP2 beta gene, while the 3.8-kb-long DNA segment encoding the TcP2 beta-H1.8 locus showed two TcP2 beta genes arranged in tandem . These genes were physically connected by a 428-bp-long DNA sequence that was also located immediately 5' to the first gene and immediately 3' to the second . Comparison of the 4 TcP2 beta gene loci, suggested that the insertion of this repeated element originated the duplication of its target sequence, a poly(dT) stretch . Approximately 1200 copies of this short sequence, named short interspersed repetitive element (SIRE), were found scattered in the genome . Analysis of the 5' non-coding regions of different TcP2 beta mRNAs, and RNA-PCR experiments suggested that the insertion of a SIRE upstream of a TcP2 beta-H1.8 gene introduced a new 3' spliced leader (SL) acceptor site in the TcP2 beta-H1.8 pre-mRNAs, encoded within the SIRE . Consequently, in the mature H1.8 mRNA the SL sequence is followed by 38 bases directly transcribed from the SIRE . Structural and functional features of this repeated element reveal similarity to the short interspersed repetitive DNA sequences detected in the genomes of several microorganisms.

Appl Environ Microbiol, 1994 Apr, 60(4), 1059 - 67
Use of molecular techniques to evaluate the survival of a microorganism injected into an aquifer; Thiem SM et al.; A PCR primer set and an internal probe that are specific for Pseudomonas sp . strain B13, a 3-chlorobenzoate-metabolizing strain, were developed . Using this primer set and probe, we were able to detect Pseudomonas sp . strain B13 DNA sequences in DNA extracted from aquifer samples 14.5 months after Pseudomonas sp . strain B13 had been injected into a sand and gravel aquifer . This primer set and probe were also used to analyze isolates from 3-chlorobenzoate enrichments of the aquifer samples by Southern blot analysis . Hybridization of Southern blots with the Pseudomonas sp . strain B13-specific probe and a catabolic probe in conjunction with restriction fragment length polymorphism (RFLP) analysis of ribosome genes was used to determine that viable Pseudomonas sp . strain B13 persisted in this environment . We isolated a new 3-chlorobenzoate-degrading strain from one of these enrichment cultures . The B13-specific probe does not hybridize to DNA from this isolate . The new strain could be the result of gene exchange between Pseudomonas sp . strain B13 and an indigenous bacterium . This speculation is based on an RFLP pattern of ribosome genes that differs from that of Pseudomonas sp . strain B13, the fact that identically sized restriction fragments hybridized to the catabolic gene probe, and the absence of any enrichable 3-chlorobenzoate-degrading strains in the aquifer prior to inoculation.

Biotechnology (N Y), 1994 Apr, 12(4), 375 - 80
Drug synthesis by genetically engineered microorganisms; Hutchinson CR; The interplay between chemical and biological approaches to drug discovery and development is increasing with the advent of combinatorial methods that accelerate the output of screening programs and the development of genetically modified microorganisms able to make new metabolites and larger amounts of known ones . Actinomycetes, the most prolific microbial source of known drugs, can produce new aromatic compounds by manipulation of the Type II polyketide synthase genes as well as analogs of existing macrolide antibiotics, unavailable by chemical synthesis, through targeted mutation of specific biosynthetic genes . Genetic alteration of pathways to aminoglycoside and oligopeptide antibiotics should offer equally promising approaches to manufacturing novel metabolites . When coupled with DNA-based prescreening of microbial isolates for genes associated with known pharmacologically active agents, these new genetic-based approaches are creating an expanded role for microorganisms in drug research.

J Clin Epidemiol, 1994 Apr, 47(4), 419 - 33
Sartwell's incubation period model revisited in the light of dynamic modeling; Philippe P; The objective is to look into the well-known robustness of Sartwell's disease incubation period (IP) lognormal model . A new approach is proposed that embeds the pathogenesis of infection into the framework of percolation theory derived from the physical sciences . A two-step model of the individual disease process is proposed . The first step has a stochastic basis: it is aimed at establishing the threshold position of subjects bound to be diseased . Agent and host factors entertain and help the process reach the threshold . They include all the biologic risk factors (age, exposure dose and intensity, route of inoculation, etc.) to which Sartwell's model is usually found robust . The threshold is the point of no return of the disease process . The threshold provides the initial conditions of the second step . The second step traces the evolution of the pathologic process until disease onset: it is based on a nonlinear deterministic model that progressively unfolds the individual fates . As a chaotic regime is embedded into the model and as chaos unavoidably develops at some time entailing disease onset, the IP distribution becomes independent of the initial conditions laid out at the threshold . Unpredictable disease time courses and onsets are obtained . Biological examples supporting the model are provided . A simulation of 1000 pathologic processes is undertaken according to a simple birth-and-death process of microorganisms or cancer cells . As expected, a lognormal fits the IP distribution over a wide range . A lack of lengthy IPs is, however, observed . A simple multiplicative process coincides exactly with a lognormal model, but a multiplicative-competitive process such as that which is embedded in the nonlinear deterministic model has a narrower distribution . Large sample sizes are, however, needed to uncover this departure from the lognormal . Biologically, at least two phases of the empiric IP should be told apart: lengthy IPs should be distinguished from short and median IPs . Lengthy IPs emphasize interaction (complexity) between the disease progression and the immunological defenses of the host . Simulated distributions involving process complexity closely fit selected cancer data sets . Process complexity of the host pathologic unfolding can actually be recognized and quantified.

Mutat Res, 1994 Apr 1, 306(1), 45 - 60
Fluctuation test for two-stage mutations: application to gene amplification; Kimmel M et al.; The determination of mutation rates is an important experimental procedure for characterizing mutation processes . The accepted method of determining mutation rates, the fluctuation test, was introduced by Luria and Delbruck in 1943 . Since then it has been applied to various microorganisms and cells . The Luria-Delbruck test is based on a restrictive hypothesis of mutations being due to single irreversible events . However, some inherited changes in phenotype, like gene amplification, may be due to two or more genetic changes, some of which may be reversible . The Luria-Delbruck model of mutation was compared to other models which included reversibility and more than one mutation stage . The Luria-Delbruck model has been confirmed to be consistent with the original bacteriophage resistance data . However, for gene amplification this model gives incompatible estimates of mutation rates by the P0 and r methods . Relaxing the hypotheses of the single-stage models did not improve the fit . In contrast, a two-stage reversible model provided a fit . Analysis of gene amplification data by the two-stage reversible model provides new information, including estimates of rates for each of the two forward stages and of the reverse step.

Schweiz Med Wochenschr, 1994 Mar 19, 124(11), 452 - 60
{Current developments in the diagnosis and therapy of Crohn disease and ulcerative colitis}; Hammer B; The etiology and pathogenesis of idiopathic chronic-inflammatory bowel diseases, i.e . Crohn's disease and ulcerative colitis, are still unknown . This has no effect on diagnosis, yet does affect treatment of these diseases, which has thus remained symptomatic . Clinical features, laboratory findings, endoscopy in conjunction with histologic examination and radiologic studies are all of proven value in the diagnosis of these disorders . Microbiologic and, if indicated, serologic studies are employed to search for colitis caused by microorganisms . Other bowel disorders to be considered in differential diagnosis include ischemic, radiation and drug-induced forms of colitis, as well as diverticulitis . More recently introduced techniques for the detection of secondary intra-abdominal processes are CT-scan and MRI (magnetic resonance imaging) . Ultrasound examination of the abdomen can be used to search for thickening of the bowel wall . Use of the rather complicated hydrocolon sonography is rarely necessary . Endo-sonography is an established method for exploration of the rectum and is particularly useful for the detection of abscesses . The role of this technique in the diagnosis of colon processes remains to be determined . Studies using radiolabeled leukocytes are of theoretical interest but not usually required in the routine work-up of such patients . The same is true of chemical analyses of the feces and testing for antineutrophil cytoplasmic antibodies . Standard systemic treatment is based on the administration of salicylic acid derivatives and corticosteroids . Azathioprine and 6-mercaptopurine can be used in patients refractory to standard treatment . Metronidazole has been proven quite effective in patients with Crohn's disease of the colon, particularly in the perianal region.(ABSTRACT TRUNCATED AT 250 WORDS)

J Biol Chem, 1994 Mar 18, 269(11), 8022 - 8
Interactions of cyclic hydrocarbons with biological membranes; Sikkema J et al.; Many cyclic hydrocarbons, e.g . aromatics, cycloalkanes, and terpenes, are toxic to microorganisms . The primary site of the toxic action is probably the cytoplasmic membrane, but the mechanism of the toxicity is still poorly understood . The effects of cyclic hydrocarbons were studied in liposomes prepared from Escherichia coli phospholipids . The membrane-buffer partition coefficients of the cyclic hydrocarbons revealed that these lipophilic compounds preferentially reside in the membrane . The partition coefficients closely correlated with the partition coefficients of these compounds in a standard octanol-water system . The accumulation of hydrocarbon molecules resulted in swelling of the membrane bilayer, as assessed by the release of fluorescence self-quenching of fluorescent fatty acid and phospholipid analogs . Parallel to the expansion of the membrane, an increase in membrane fluidity was observed . These effects on the integrity of the membrane caused an increased passive flux of protons and carboxyfluorescein . In cytochrome c oxidase containing proteoliposomes, both components of the proton motive force, the pH gradient and the electrical potential, were dissipated with increasing concentrations of cyclic hydrocarbons . The dissipating effect was primarily the result of an increased permeability of the membrane for protons (ions) . At higher concentrations, cytochrome c oxidase was also inactivated . The effective concentrations of the different cyclic hydrocarbons correlated with their partition coefficients between the membrane and aqueous phase . The impairment of microbial activity by the cyclic hydrocarbons most likely results from hydrophobic interaction with the membrane, which affects the functioning of the membrane and membrane-embedded proteins.

Structure, 1994 Mar 15, 2(3), 209 - 19
Structures of a legume lectin complexed with the human lactotransferrin N2 fragment, and with an isolated biantennary glycopeptide: role of the fucose moiety; Bourne Y et al.; BACKGROUND: Lectins mediate cell-cell interactions by specifically recognizing oligosaccharide chains . Legume lectins serve as mediators for the symbiotic interactions between plants and nitrogen-fixing microorganisms, an important process in the nitrogen cycle . Lectins from the Viciae tribe have a high affinity for the fucosylated biantennary N-acetyllactosamine-type glycans which are to be found in the majority of N-glycosylproteins . While the structures of several lectins complexed with incomplete oligosaccharides have been solved, no previous structure has included the complete glycoprotein . RESULTS: We have determined the crystal structures of Lathyrus ochrus isolectin II complexed with the N2 monoglycosylated fragment of human lactotransferrin (18 kDa) and an isolated glycopeptide (2.1 kDa) fragment of human lactotransferrin (at 3.3 A and 2.8 A resolution, respectively) . Comparison between the two structures showed that the protein part of the glycoprotein has little influence on either the stabilization of the complex or the sugar conformation . In both cases the oligosaccharide adopts the same extended conformation . Besides the essential mannose moiety of the monosaccharide-binding site, the fucose-1' of the core has a large surface of interaction with the lectin . This oligosaccharide conformation differs substantially from that seen in the previously determined isolectin I-octasaccharide complex . Comparison of our structure with that of concanavalin A (ConA) suggests that the ConA binding site cannot accommodate this fucose . CONCLUSIONS: Our results explain the observation that Viciae lectins have a higher affinity for fucosylated oligosaccharides than for unfucosylated ones, whereas the affinity of ConA for these types of oligosaccharides is similar . This explanation is testable by mutagenesis experiments . Our structure shows a large complementary surface area between the oligosaccharide and the lectin, in contrast with the recently determined structure of a complex between the carbohydrate recognition domain of a C-type mammalian lectin and an oligomannoside, where only the non-reducing terminal mannose residue interacts with the lectin.

Tidsskr Nor Laegeforen, 1994 Mar 10, 114(7), 814 - 7
{Acute bronchitis in adults . Clinical findings, microorganisms and use of antibiotics}; Melbye H et al.; Among 72 adult patients with a diagnosis of acute bronchitis, serological investigation established the presence of an aetiologic agent in 29 (40%) . Influenza virus was the most common pathogen . Seven patients had bacterial infection, caused by pneumococci in four patients and Mycoplasma pneumoniae in three . Five of the patients had pneumonia as diagnosed by radiography, and mycoplasmal aetiology was established in one of these . Altogether, 11 patients either had bacterial infection or radiographic pneumonia . Although the doctors' recording of wheezes was strongly associated with prescription of antibiotics (p < 0.0001), wheezes were heard only in two of the 11 patients with pneumonia or bacterial infection, compared with 30 of the 61 patients with viral or unspecified bronchitis . The median value of C-reactive protein (CRP) was 52 mg/l in the 11 patients, significantly higher than < 11 mg/l in the 61 other patients (p < 0.0001) . The corresponding values for erythrocyte sedimentation rate were 45 and 14 mm/h (p < 0.0005) . The results indicate that certain patients with acute bronchitis should be treated with antibiotics, and that the erythrocyte sedimentation rate and the CRP-test may be useful in detecting which patients this applies to.

J Med Entomol, 1994 Mar, 31(2), 202 - 5
New artificial feeding technique for experimental infection of Argas ticks (Acari: Argasidae); Abbassy MM et al.; An artificial feeding technique using fetal bovine serum as a food source was established for the demonstration of West Nile virus transmission by Argas ticks in susceptibility studies . Fetal bovine serum does not coagulate and is free from contaminating microorganisms, antibodies, and anticoagulants, which are all known to reduce virus titers . This technique also compensates for the lack of suitable laboratory hosts as well as problems associated with disease agents, such as viruses that may not produce illness or antibodies after virus exposures.

Clin Lab Med, 1994 Mar, 14(1), 83 - 97
Laboratory detection of fungemia; Geha DJ et al.; Patients who are immunosuppressed, receiving broad-spectrum antibiotics, or with intravascular catheters in place are at risk for invasive fungal infections . In a significant number nosocomial fungal infections develop . The diagnosis of invasive fungal disease often relies on the detection of the etiologic agent using blood cultures . Great progress has been made in fungal blood culturing over the past 20 years with the development of biphasic media, automated radiometric and nonradiometric systems, and LCS used with selective culture media . The biphasic BHI and Septi-Chek systems provide recovery of the majority of fungal isolates, yet there frequently is an undesirable delay in detection . Lysis of blood cells, aeration by venting, and agitated incubation improve detection with these systems . Automated systems often require a significant initial financial investment but have been shown to be durable and effective in most aspects of blood culturing . They have a limited daily hands on requirement . The newer nonradiometric systems appear to be better than the older systems, especially in time to detection and in the reduction of false-positive signals . The most significant factors, however, may be the volume of blood used in these systems and the resins incorporated in the media to eliminate inhibitors of fungal growth . A significant disadvantage of the automated systems has been their failure to detect certain organisms (C . neoformans and dimorphic fungi); however, the use of newer culture media as well as blind subculturing may partially alleviate this problem . Lysis-centrifugation blood culturing has performed well, is highly sensitive, and permits recovery of both fungi and aerobic bacteria . Because it is flexible, the media selection can be altered to suit any specific growth requirement . It is rapid and permits the identification of most yeast and yeastlike microorganisms within 4 days and of H . capsulatum within 3 weeks . Because this system utilizes solid media, blind subculturing is unnecessary . Quantitation of fungemia is possible and may permit determination of the clinical importance of the microorganism and assessment of the patient's response to treatment . The disadvantages of this system are that it requires a significant amount of the technologist's time to process the specimen, inoculate the various media, and visually examine the culture media throughout the incubation period . A significant contamination rate still exists despite working within a laminar flow biosafety cabinet; this also increases time requirements . The detection of fungemia has markedly improved; the times to detection have decreased to the point of being clinically useful, and several systems are available to accommodate individual laboratory needs.(ABSTRACT TRUNCATED AT 400 WORDS)

Clin Lab Med, 1994 Mar, 14(1), 31 - 49
Blood cultures and immunocompromised patients; Stratton CW; The diagnosis of blood-borne infections in immunocompromised patients is a major challenge for the clinical microbiology laboratory . Isolation of blood-borne pathogens in these patients has profound clinical implications, yet is fraught with technical problems . Contamination of blood cultures by skin flora is particularly problematic in the immunosuppressed host as these low-virulence microorganisms can be the cause of infection . Careful skin preparation is necessary to minimize such contamination . Drawing at least two blood samples for culture improves the specificity of this test on an individual patient . If possible, blood for culture should not be obtained through indwelling vascular devices . The microbiology laboratory must be aware of the wide range of blood-borne pathogens in immunocompromised patients and have available suitable techniques for the isolation of prevalent microorganisms . For most hospitals, this now must include techniques for the isolation of mycobacteria . Newer blood culture techniques have made the isolation of unusual pathogens easier . These techniques include the use of fluorescent stains, special media, antigen assays, and DNA probes . Each laboratory must evaluate current techniques in terms of suitability for use in its individual setting . Each must also be aware of new technologic developments . When clinical infection is suspected despite negative blood cultures, staff in the microbiology laboratory should be aware of special blood culture techniques or adjunctive procedures such as bone marrow and liver biopsies . These techniques may assist the clinician in making a diagnosis . Due to the practical limitations of blood culture technology as well as to economic constraints, the microbiology laboratory cannot routinely offer blood cultures suitable for the isolation of all blood-borne pathogens . Therefore, the microbiology laboratory must act in consultation with the clinician to determine the optimal approach for blood cultures in the immunocompromised patient . Such a consultative role with special blood culture techniques made available for selected types of immunosuppressed hosts allows the cost-effective use of the latest technology.

Clin Lab Med, 1994 Mar, 14(1), 119 - 31
Recovery of select rare and fastidious microorganisms from blood cultures; Wilson ML et al.; Most, if not all, rare or fastidious microbial pathogens can be recovered from standard blood culture bottles and media using routine laboratory methods . Because they are only rarely recovered from blood cultures, relatively few data exist concerning the ability of different blood culture systems to recover these microorganisms . Thus, clinical microbiologists should take a conservative approach when processing blood cultures that may contain one of the microorganisms reviewed in this article, including the use of additional media, media supplements, blind and terminal subcultures, or prolonged incubation and testing.

Cesk Epidemiol Mikrobiol Imunol, 1994 Mar, 43(1), 23 - 5
{Unusual causes of chromomycosis}; Tomsikova A; The typical clinical picture and mycological and histological basis of chromomycosis is compared with the clinical course, which is encountered more often nowadays . It refers also to the affection of the vascular, respiratory, lymphatic system, the brain and the dissemination in compromised patients . For this reason chromomycosis should rank among opportunistic mycoses . Chromohyphomycosis characterized by skin nodules occurs very rarely . Subcutaneous abscesses also called phaeomycotic cysts, are more frequent especially after corticoid and immunosuppressive therapy . Among three Czechoslovak cases of chromomycosis, the case in Pilsen can be evaluated as uncommon . It was caused by Phialophora pedrosoi and passed as a skin form of chromomycosis . The lesion developed on the right forefinger of a patient who never visited tropical countries . She never was seriously ill, never treated with antibiotics, chemotherapeutics, or corticosteroids . The histological examination of the excision revealed a granuloma with histiocytes and many giant cells phagocytizing typical spherical brown microorganisms . The patient was cured by KI, intraiodine and X-ray therapy.

Am J Forensic Med Pathol, 1994 Mar, 15(1), 28 - 31
Acute pancreatitis in a prisoner with AIDS . Bugs or drugs?
Cina SJ, Conradi SE.
Acute pancreatitis has been the cause of death in several patients with AIDS and AIDS-related complex (ARC) . Documented etiologies include several microorganisms and adverse drug reactions . We present a case of an HIV-positive prison inmate who died of acute necrotizing pancreatitis . Although he was infected with Mycobacterium avium-intracellulare, it is more likely that 2',3'-dideoxyinosine, an antiretroviral agent, induced pancreatitis . It is important to obtain a thorough pharmaceutical history in HIV-positive patients . Fatal medicinal reactions may result in death in ARC or AIDS patients . Documentation of opportunistic infection in AIDS patients may prove difficult and expensive, but costs may be minimized and diagnostic accuracy optimized if appropriate tissue samples, including lymph nodes, are submitted for histologic analysis.

Kokubyo Gakkai Zasshi, 1994 Mar, 61(1), 71 - 81
{A study on distribution of Porphyromonas gingivalis in oral cavity by using a non-radioactive DNA probe method}; Kojima T; The purpose of this study was to evaluate the distribution of Porphyromonas gingivalis (P . gingivalis) in the dentition using a non-radioactive DNA probe and to compare the presence of P . gingivalis with the clinical parameters . Fifteen adult periodontitis patients and 6 clinically healthy volunteers were examined . Subgingival plaque samples were taken from 4 sites of all the remaining teeth . Probing depth and bleeding on probing (BOP) were also recorded . Plaque samples were investigated using a whole genomic DNA probe from P . gingivalis modified with bisulfite . In the patient group, the detection percentage and the amounts of P . gingivalis present were statistically compared with probing depth and BOP . As a result, P . gingivalis was detected in all 15 patients and 3 out of 6 healthy individuals . The detection average was 31% in the patient group . When the probing depth was over 4mm, 6mm or the BOP was positive, the detection percentage of P . gingivalis significantly increased in the patient group . As more P . gingivalis was identified, the percentage of the sites with deep probing depth or that were BOP-positive increased . However, P . gingivalis was also detected in the clinically healthy sites, and also it was not detected in some sites with deep probing depth or that were BOP-positive . These results indicate that P . gingivalis plays an important role, but is not the only microorganism responsible for adult periodontitis.

J Clin Periodontol, 1994 Mar, 21(3), 177 - 83
Ex vivo studies of polymorphonuclear neutrophils from patients with early-onset forms of periodontitis . (I) . Chemotactic assessment using the under agarose method; Mouynet P et al.; The polymorphonuclear neutrophil (PMN) appears to be an important cell in the protection of the host from pathogenic periodontal microorganisms and, despite some reports to the contrary, it is generally assumed that early-onset forms of periodontal disease (including both juvenile and rapidly progressing periodontitis) are associated with a defect in PMN chemotactic behaviour . The purpose of the present study was to examine the peripheral PMN chemotactic behaviour, using the under agarose method, in 4 groups, namely healthy periodontium group (n = 7), gingivitis group (n = 8), early-onset periodontitis group (n = 17) and adult periodontitis group (n = 8) . PMN from early-onset periodontitis patients showed normal random and chemotactic locomotory behaviour when compared with those of PMN from subjects of the other groups . No statistically significant difference could be found among the 4 studied groups, with regard to spontaneous and oriented migration.

Trends Microbiol, 1994 Mar, 2(3), 76 - 81
Short-sighted evolution and the virulence of pathogenic microorganisms; Levin BR et al.; For some microorganisms, virulence may be an inadvertent consequence of mutation and selection in the parasite population, occurring within a host during the course of an infection . This type of virulence is short-sighted, in that it engenders no advantage to the pathogen beyond the afflicted host . Bacterial meningitis, poliomyelitis and AIDS are three candidates for this model of the evolution of virulence.

Infect Immun, 1994 Mar, 62(3), 769 - 78
Heparin-inhibitable lectin activity of the filamentous hemagglutinin adhesin of Bordetella pertussis; Menozzi FD et al.; Bordetella pertussis, the etiologic agent of whooping cough, produces an outer membrane-associated filamentous hemagglutinin (FHA) which is the major adhesin of this organism . FHA exhibits a lectin-like activity for heparin and dextran sulfate . By using in vitro adherence assays to cultured epithelial cells, the attachment of B . pertussis was reduced in the presence of sulfated polysaccharides such as heparin and dextran sulfate but not in the presence of dextran, indicating the crucial role of polysaccharide sulfation . In addition, inhibition of cellular sulfation by chlorate treatment of the cells resulted in a reduction of B . pertussis adherence, suggesting that epithelial cell surface-exposed sulfated glycoconjugates may serve as receptors for the microorganism . B . pertussis mutant strains deficient in FHA production expressed residual adherence that was no longer inhibited by sulfated polysaccharides . In addition, purified FHA displayed heparin-inhibitable binding to epithelial cells . Mapping experiments of the heparin-binding site of FHA indicated that this site is different from the RGD site and the recently proposed carbohydrate-binding site involved in the interaction of FHA with lactosylceramide . This result demonstrates that FHA contains at least three different binding sites, a feature unusual for bacterial adhesions but similar to features of eukaryotic adhesins and extracellular matrix proteins.

Bull Acad Natl Med, 1994 Mar, 178(3), 551 - 65; discussion 565-8
{Absorption, distribution and excretion of vitamin B12}; Nicolas JP et al.; In our first communication, the complexity of vitamin B12 digestive transport was considered . This second presentation demonstrates the route of the vitamin in the body . As cobalamin or vitamin B12 has existed for Four Billion Years, they figure without any doubt amongst those molecules which have the most complex structure . The rarity of an architecture organised around a cobalt atom confirms their high level of originality . Their exceptional character is reflected in their cycle such as for mammals and for man where the intervention of binders, such as intrinsic factor, transcobalamin and haptocorrin is necessary for transporting them . As far as cellular metabolism is concerned, it is especially loaded sometimes with folates in the transfer of the methyl group . The Molecules are spiked with hydrophobic sites . Their membrane transfer is facilitated by several types of receptors . The intestinal absorption, which appears to require the presence of two receptors and two transporters, remains for the moment a unique assimilation model . The very probable existence of an enterohepatic cycle as well as a renal reabsorption saves this molecule, itself synthesised by microorganisms only.

Med J Malaysia, 1994 Mar, 49(1), 74 - 7
Cytopathologic changes associated with intrauterine contraceptive devices . A review of cervico-vaginal smears in 350 women; Pillay B et al.; Cervico-vaginal smears from 350 IUCD users were analysed to ascertain the range of abnormalities induced in the genital tract of these women . Alteration of the microbial environment, inflammatory, degenerative, reparative and proplastic epithelial changes were the salient cytological findings . The clinical implications of these are briefly discussedPIP: Researchers examined results of cervico-vaginal smears of 350 women aged 23-45 years fitted with IUDs at various family planning clinics in Kuala Lumpur, Malaysia, to examine abnormalities in their genital tract . All the women had undergone preinsertion cervico-vaginal smears . They used the IUD for 1-8 years . Around 66% exhibited symptoms after IUD insertion . 40% had vaginal discharge, especially mucous . 3% had pelvic pain and intermittent low grade fever, suggesting pelvic inflammatory disease . 80% had an increase in the number of leukocytes in their blood . 42% had an increase in the number of histiocytes with multinucleate giant forms . The following microorganisms were present: Gardnerella vaginalis (42%), Trichomonas vaginalis (32%), Candida (28%), Actinomyces-like organisms (2%), and non-pathogenic Amoeba (0.6%) . Both endocervical and squamous columnar cells exhibited morphological atypias (inflammatory, degenerative, or reparative changes) . 70% of atypias were benign and varied from mild to severe . 14 women (4%) had cervical intra-epithelial neoplasia (CIN) . 3% of the women had atypical single cells . The IUDs were removed from all of these women . 6 months after IUD removal, the cervixes with mild dysplasia had reverted to normal . Two women with severe dysplasia underwent cervical biopsy, which revealed a CIN III lesion . 28% of smears had abnormal or irritated glandular epithelial endocervical and endometrial cells with hyperchromatic nuclei, an increased nucleo-cytoplasmic ratio, and bubble-gum vacuolation of the cytoplasm . 31% of the women had normal or inflamed out-of-phase (beyond day 11 of the menstrual cycle) endometrial cells . 80% of these 109 women had menorrhagia or intermenstrual bleeding . The researchers recommend that serious epithelial atypias be followed up and the IUD be removed . IUD removal allows clinicians to determine whether atypias will regress in the absence of an IUD or are truly neoplastic .

J Antimicrob Chemother, 1994 Mar, 33(3), 523 - 36
Investigation of dirithromycin and erythromycylamine uptake by human neutrophils in vitro; Mtairag EM et al.; Dirithromycin, a new semisynthetic 14-membered-ring macrolide was avidly concentrated by human neutrophils in a time- but not concentration-dependent manner with mean cellular/extracellular, concentration ratios (C/E) of 9 within the first 5 min and up to 47 at 120 min . Erythromycylamine, the hydrolysis product of dirithromycin, was concentrated significantly less by neutrophils, reaching C/E values of 4 and 19 (at 5 and 120 min) . A point of interest was the interindividual variability in the antibiotic uptake kinetics; in particular, 7 out of 47 neutrophil samples from different healthy volunteers displayed very slow uptake of both drugs (C/E values at 30 min: dirithromycin, 5.8; erythromycylamine, 4.6) . The reason(s) for this is unknown . The uptake of both drugs was decreased at acidic pH and increased at basic pH . Chloroquine, an antimalarial drug which is concentrated in and alkalinizes azurophilic granules, reduced uptake by half . Metabolic inhibitors (2-4 dinitrophenol, sodium fluoride, potassium cyanide and sodium azide) did not impair the uptake of either drug but, interestingly, ouabain, an inhibitor of membrane Na+/K+ ATPase activity, impaired uptake by about 30% . Competitive inhibitors of some transport systems identified on neutrophil membrane (nucleosides, D-glucose and various aminoacids) did not alter the uptake of either drug . Dirithromycin and to a lesser extent, erythromycylamine, reached intracellular concentrations much higher than those required to inhibit the growth of sensitive microorganisms . Although the mechanism of uptake is not clear, one interesting hypothesis involves trapping by protonation into acidic compartments of neutrophils.

J Perinatol, 1994 Mar-Apr, 14(2), 134 - 44
Uncommon pathogens in newborn infants; Giacoia GP; Newborns, especially premature newborns, are immunocompromised and have increased susceptibility to infections by opportunistic organisms . Experience with these uncommon pathogens is limited to a handful of case reports and to several reports of neonatal intensive care nursery outbreaks . Many of these infections are misdiagnosed or diagnosed at autopsy because of the nonspecific features of their clinical presentation, difficulties in recovering the pathogen from body fluids, or because the microorganism is considered either a contaminant or nonpathogenic . This review summarizes the clinical characteristics of these uncommon pathogens and emphasizes the existence of dual and polymicrobial infections . The limited experience with many of these infections precludes the formulation of an optimal therapeutic approach.

Enferm Infecc Microbiol Clin, 1994 Mar, 12(3), 150 - 3
{Tuberculous meningitis caused by resistant microorganisms . Therapeuticfailure in 2 patients with HIV infection and disseminated tuberculosis}; Fortun J et al.; BACKGROUND: Tuberculosis in HIV infected patients does not carry a worse therapeutic response rate . Treatment failure is usually due to incomplete schedule, with development of acquired resistance . Two patients with HIV infection and disseminated tuberculosis who developed fatal meningitis are presented . METHODS: In vitro studies of sensitivity to anti-tuberculous drugs were carried out, using the proportions method . RESULTS: Following a good initial evolution, both patients were readmitted with tuberculous meningitis resistant to isoniazide in both and to rifampicin in one of the patients . In one patient, the original strain (which was sensitive) was available . In this patient, changes in the treatment were performed in the initial phase . CONCLUSIONS: The importance of anti-tuberculous multiple therapy, particularly in the initial phases, for HIV positive patients is crucial . The lengthen of admission when good patient's compliance is in question, but also to avoid, whenever possible, changes in treatment are important measures in this stage . Meningitis may occur as a form of therapeutic failure and its cure may be difficult if the strains are resistant.

Vet Q, 1994 Mar, 16(1), 45 - 50
Role of the neutrophil leucocyte in the local and systemic reactions during experimentally induced E . coli mastitis in cows immediately after calving; Burvenich C et al.; Mammary leucocytes are the major contributors to natural defence against mastitis after a microorganism has entered the gland . This paper reviews the role of the neutrophil granulocyte during acute coliform mastitis in cows in the periparturient period . Qualitative and quantitative aspects of several neutrophil cell functions before and during experimentally induced infections are briefly discussed.

Oper Dent, 1994 Mar-Apr, 19(2), 65 - 9
Histobacteriological analysis of acid red dye-stainable dentin found beneath intact amalgam restorations; Boston DW et al.; This study determined histologically the incidence of acid red dye-stainable dentin and its correlation to bacterial presence beneath intact clinically sound amalgam restorations . Fourteen of 16 clinically sound amalgam restorations (88%), serving an average of 11 years, had microscopically evident microorganisms in the subjacent dentin . Eleven of the 14 specimens containing bacteria (79%) exhibited acid red dye-stainable dentin . There was no obvious correlation between dye-stainable dentin and the presence of bacteria on the walls of the cavity preparations studied . The question of how much dye-stainable dentin can be present beneath an amalgam restoration before the restoration fails is still unanswered.

Genetics, 1994 Mar, 136(3), 993 - 9
Cytoplasmic incompatibility in Australian populations of Drosophila melanogaster; Hoffmann AA et al.; In Drosophila melanogaster, weak incompatibility in crosses between infected and uninfected strains is associated with a Wolbachia microorganism . Crosses between infected males and uninfected females show a reduction (15-30%) in egg hatch . Progeny tests indicated that the infection is widespread in Australian D . melanogaster populations and that populations are polymorphic for the presence of the infection . The infection status of 266 lines from 12 populations along the eastern coast of Australia was determined by 4',6-diamidino-2-phenylindole (DAPI) staining of embryos . All populations contained both infected and uninfected flies . Infection frequencies varied between populations but there was no discernible geographical pattern . Laboratory experiments indicated that the infection was not associated with a reduction in fecundity as in Drosophila simulans . Incompatibility levels could not be increased by laboratory selection on isofemale lines . Factors contributing to the persistence of the infection in D . melanogaster populations are discussed.

Res Immunol, 1994 Mar-Apr, 145(3), 165 - 83
Mechanisms of autoimmunity and AIDS: prospects for therapeutic intervention; Atlan H et al.; The network theory of autoimmunity is presented with recent experimental data relevant to the understanding of the pathogenesis of AIDS . Schematically, effector T cells specific for self-antigens exist normally, but their activity is modulated and prevented by networks of regulatory T cells . As a result of mimicry between molecular components of microorganisms and self-antigens, autoimmune disease can be triggered by specific foreign pathogens which alter the state of activity of the network from suppression to activation . Conversely, by a procedure known as T-cell vaccination, autologous effector T cells re-injected after in vitro stimulation and attenuation may alter the state of the network from an activation to a suppression . Numerous observations are reviewed that support the concept of autoimmune activity in the destruction of non-infected T4 cells . Such activity is presumed to be triggered by an antigen of viral origin, the most likely, but not the only one, being the envelope protein gp 120 . Based on this hypothesis, a T-cell vaccination procedure against effector T cells responsible for autoimmunopathic activity in HIV-seropositive patients is proposed, similar to the one known from experimental study of autoimmunity and presently being tested in human autoimmune diseases . Its purpose would be to prevent T-cell loss and the onset of immunodeficiency disease in HIV-seropositive patients . Apart from its potential therapeutic value, this procedure will have use as a therapeutic test from which insight will be gained about the immunopathogenesis of AIDS.

Microbiologia, 1994 Mar-Jun, 10(1-2), 49 - 56
{Grouping of the genes of biosynthesis and resistance to beta-lactam antibiotics in cephamycin-C producing actinomycetes}; Liras P et al.; Three genes related to beta-lactam resistance have been found in the cluster of genes for cephamycin C biosynthesis in Nocardia lactamdurans . The cmcT gene encodes a hydrophobic protein located in the cytoplasmic membrane . The sequence of CMCT has a 21-31% identity in amino acids to proteins involved in antibiotic export from other antibiotic producing microorganisms . The pbp gene encodes a penicillin binding protein . Nocardia lactamdurans is rather sensitive to penicillins, but no to cephalosporins or cephamycin C . A third gene, bla, encodes a type A beta-lactamase . Both the beta-lactamase and the PBP protein, might form a system for the sensing and hydrolysis of penicillin intermediates which are released into the medium during the lysis of antibiotic producing cells.

Microbiologia, 1994 Mar-Jun, 10(1-2), 121 - 30
Biocorrosion produced by Thiobacillus-like microorganisms; Lopez AI et al.; Biocorrosion can be produced by many different microorganisms through diverse mechanisms . The biocorrosion produced by acidophilic microorganisms of the genus Thiobacillus is based on the production of sulfuric acid and ferric ion from pyrites or related mineral structures, as a result of the chemolithotrophic metabolism of these microorganisms . The products of this aerobic respiration are also powerful oxidant elements, which can produce chemical oxidations of other metallic structures . The Tinto River, a very unusual extremophilic habitat (pH around 2, and high concentration of ferric ion), product of the growth of strict chemolithotrophic microorganisms, is discussed as a model case.

Z Gastroenterol, 1994 Mar, 32(3), 174 - 81
{Gastrointestinal manifestations of HIV infection}; Schneider T et al.; The intestinal (in particular rectal) mucosa is the main portal of entry for HIV in homosexual men, who represent the vast majority of HIV-infected patients in Europe and North America . There are several possibilities for HIV to reach the CD4-positive T cells, macrophages and follicular-dendritic cells in the intestinal mucosa . HIV may be transported through M-cells directly to mucosal lymph follicles . Alternatively HIV may infect enterocytes via Fc-receptor by antibody-bound HIV or via a CD4-independent receptor . By successive budding on the basolateral side of the enterocytes HIV may be released into the lamina propria . The loss and functional impairment of activated CD4-positive lamina propria T-cells could be responsible for both the decreased immune defense and altered structure and function of the mucosa . The common intestinal symptoms in HIV-infected patients may be caused by a variety of mechanisms . The high number of secondary opportunistic or non-opportunistic infections and secondary malignancies of the gut may be responsible for the observed symptoms . However, the pathogenic relevance of some of these pathogens is questionable since there is often no correlation between symptoms and presence of the pathogen . In addition, there is a considerable percentage of symptomatic patients without identifiable microorganisms . Yet unidentified pathogens, small intestinal bacterial overgrowth, damage of intestinal nerve fibres, or secretory diarrhea may contribute to the pathogenesis of gastrointestinal symptoms . The findings of a pathogen-negative diarrhea, of HIV-infected mononuclear cells in the gut, and of epithelial hypoproliferation and enterocyte dysmaturation is in agreement with the hypothesis that there is an enteropathy caused by HIV itself.

Comp Biochem Physiol Biochem Mol Biol, 1994 Mar, 107(3), 489 - 94
Comparative inhibition patterns of adenylate kinases from mammals, bird, fish and microorganisms; Williams A et al.; The S8 inhibitions of AKs from six different sources were studied in mammals, birds, fish, and a microorganism . All AKs tested were inhibited by S8 . Except for carp, all inhibited AKs from those tested were reactivated by DTT . Inhibitions of AKs by other hydrophobic inhibitors, NEM, butanol and ethanol were also studied . The inhibitions by S8 suggest that the hydrophobic pockets in the AKs cover a wide phylogenetic range . All inhibitions by S8 are reactivated by DTT . Unlike the inhibitions by S8, the characteristics of inhibitions by the other hydrophobic inhibitors differed among the AK sources tested and none was the irreversible type . The data suggest that no covalent bonds were formed with NEM . Similarly, the ability to reactivate the inhibitions by DTT differed among the AK sources . The possibility that the hydrophobic domains in the AKs may serve as part of an enzyme activity control mechanism is discussed.

Arzneimittelforschung, 1994 Mar, 44(3A), 402 - 7
Biochemistry and molecular biology of nitric oxide synthases; Forstermann U; Many mammalian cells synthesize nitric oxide (NO) . Three different isoforms of NO synthase have been characterized, purified and cloned . The identity of the three isoforms at the amino acid level is 50-60%, in cases where the same isoform has been cloned from more than one species > 90% identity is found between species . Isozyme I is present in neuronal cells of the brain (where NO may mediate synaptic plasticity), in peripheral neurons (where NO acts as an atypical neurotransmitter relaxing vascular and non-vascular smooth muscle), in specialized epithelial cells, and in human skeletal muscle . Macrophages are induced with bacterial endotoxin and/or cytokines to express isozyme II . The high concentrations of NO produced by this inform have cytostatic effects on parasitic microorganisms and tumor cells . Very similar isozymes can be induced in various other cells such as smooth muscle cells, mesangial cells, endothelial cells, fibroblasts, hepatocytes, etc . The induced enzyme from rat hepatocytes has been cloned and shows 94% sequence identity with the mouse macrophage enzyme . Endothelial cells contain isoform III of NO synthase which seems to be unique for this cell type . Endothelium-derived NO is a physiologically significant vasodilator and inhibitor of platelet aggregation and adhesion . NO can also prevent leukocyte adhesion to the endothelium, and has also been shown to inhibit the proliferation of vascular smooth muscle cells . Thus at least three distinct isoforms of NO synthase are responsible for NO formation in mammals.

Clin Diagn Lab Immunol, 1994 Mar, 1(2), 150 - 4
Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens; Ruedl C et al.; We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens . After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G {IgG}, IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence . The procedure followed the principle of the classical ELISPOT test with nitrocellulose-bottomed microtiter plates, but europium (Eu3+)-linked streptavidin rather than enzyme-conjugated streptavidin was used, with the advantage of quantifying secreted immunoglobulins instead of detecting single antibody-secreting cells . Lymphocytes isolated from the lungs of treated animals revealed significant increases in total and antigen-specific IgA synthesis compared with the rates of the controls, whereas IgG and IgM production rates showed no remarkable differences . In addition, the sera of treated mice revealed higher antigen-specific IgA titers but not increased IgM and IgG levels . We conclude that priming the gut-associated lymphoid tissue with bacterial antigens of pneumotropic microorganisms can elicit an enhanced IgA response in a distant mucosal effector site, such as the respiratory tract, according to the concept of a common mucosa-associated immune system.

J Biotechnol, 1994 Feb 28, 32(3), 221 - 9
Investigation of oxygen transfer through the membrane of polymer hollowspheres by oxygen micro-electrodes; Wiesmann R et al.; Estimation of oxygen transfer from an aqueous solution into polymer hollow spheres, as used for encapsulation of microorganisms, requires detection of the dissolved oxygen concentration inside the hollow sphere . Using microcoaxial needle electrodes, oxygen kinetics in different penetration depths within single cellulose-sulfate hollow spheres loaded with and without living yeast cells could be measured . Based on the reaction kinetics the diffusion coefficient for oxygen and the oxygen-uptake rate have been calculated . The diffusion coefficient DO2 within the thin membrane of cell-free spheres was in the order of 10(-10)m2s-1 . Due to the liquid core of the hollow sphere the corresponding diffusion coefficient DO2 is in the range of the value for water . The oxygen-uptake rate QO2 in cell containing spheres could be estimated to 90 mmol l-1 h-1, which corresponds to a specific oxygen-uptake rate qO2 of 10 mmol g-1 h-1 . It is to conclude that oxygen supply of the microorganisms inside the hollow spheres was, in this case, not critically influenced by the thin polymeric wall of the capsules.

FEMS Microbiol Lett, 1994 Feb 15, 116(2), 189 - 93
Microorganisms surviving for 5300 years; Haselwandter K et al.; Recently, the well-preserved corpse of a prehistoric man with an age of approximately 5300 years bp was discovered in the Central European Alps . Analysis of materials associated with the individual has revealed the presence of microorganisms which are believed to have survived since the time of death . So far, two fungi have been isolated and identified as species of the genera Chaetomium and Absidia, respectively . In addition, we have obtained one bacterial isolate which we have identified as a Streptomyces species . Our findings demonstrate that microorganisms can remain viable under appropriate circumstances for thousands of years . The isolates may enable us to study evolutionary trends within microorganisms.

Tijdschr Diergeneeskd, 1994 Feb 15, 119(4), 93 - 8
{Quality care in meat production . 'From Von Ostertag to total quality care'}; van Logtestijn JG; Von Ostertag developed the scientific basis for the system of meat inspection which is still applied over practically the whole world . The decision as to whether meat is fit for human consumption is based on observations made by the veterinarian or his/her assistant before and after slaughter . This system has worked well for years, particularly in the time when various infectious zoonoses were important . Recently, however, the system has been found more and more lacking . For example protection of the consumer from residues and enteropathogenic microorganisms is insufficient . A new analysis of the risks, which are, in fact what meat inspection is about, must be carried out . The costs of inspection are no longer considered to be in the right proportion to the actual level of public health protection . It is useful and necessary to provide the consumer with adequate guarantees, not only with respect to safety, but also with respect to the quality of the products and even the way in which they are produced (environmental aspects, well-being of animals, responsible use of feedstuffs and animal handling systems, etc.) . The situation in the animal production sector (health status of the herd, animal health care, consumer/market orientated production, etc.) also makes a different set-up necessary . The traditional meat inspection as the last step in animal production must make way for a system whereby the whole of production can be taken into account and the consumer can be given a total package of all relevant desired guarantees, paired with all relevant information on production methods and products.

Schweiz Med Wochenschr, 1994 Feb 12, 124(6), 236 - 40
{Pneumonia in patients with mechanical ventilation: physiopathology and prevention}; Troillet N et al.; Nosocomial pneumonias are due to various causes and their development depends mainly on the underlying condition of the patients . Intubated patients are prone to develop bacterial pneumonia, with microorganisms found in the oro-pharyngeal or gastric flora . Prevention relies on diminishing the exogenous and endogenous colonization of the tracheobronchial tree through: avoidance of cross contamination, maintenance of a physiological gastric pH and, possibly, selective digestive decontamination.

Ann Otol Rhinol Laryngol, 1994 Feb, 103(2), 135 - 8
Mycoplasma and Chlamydia in adenoids and tonsils of children undergoing adenoidectomy or tonsillectomy; Huminer D et al.; The prevalence of mycoplasmal and chlamydial infection was assessed in 83 children undergoing adenoidectomy, tonsillectomy, or both procedures for recurrent adenotonsillitis or obstructive symptoms . Throat smears (surface specimens) and minced adenoids and tonsils (core specimens) were cultured for Mycoplasma spp and for Chlamydia spp . Isolation rates in adenoidal specimens were as follows: Mycoplasma hominis, surface 7.1% core 2.9%; and Ureaplasma urealyticum, surface 1.4%, core 2.9% . Mycoplasma hominis was also found in tonsillar specimens: surface 14.3%, core 20% . Chlamydia trachomatis was isolated only from a single core adenoidal specimen . The rate of mycoplasma isolation was significantly higher in children with recurrent adenotonsillitis (34.5%) than in those with obstructive symptoms (3.7%) . Our findings document colonization of genital mycoplasmas in adenoids and tonsils of children with recurrent adenotonsillitis . Further studies are needed to evaluate the possible pathogenetic role of these microorganisms in adenotonsillar infection.

Crit Care Med, 1994 Feb, 22(2), 265 - 72
Role of early enteral feeding and acute starvation on postburn bacterial translocation and host defense: prospective, randomized trials; Gianotti L et al.; OBJECTIVES: To investigate the effect of: a) starvation during the preburn period and b) immediate postburn enteral nutrition on the permeability of the gut to microorganisms and the ability of the host to kill translocated bacteria . DESIGN: Prospective, randomized, experimental trials . SETTING: Laboratory . SUBJECTS: Balb/c mice and Hartley guinea pigs . INTERVENTIONS: In the first experiment, mice were starved for 0, 6, 12, 18, or 24 hrs before receiving gavage with 10(10) 14C-labeled Escherichia coli and a 20% burn injury . In the second experiment, guinea pigs received a 40% burn injury and were randomized to receive a complete enteral diet (175 kcal/kg/day) or infusion of an equal volume of lactated Ringer's solution via a previously placed gastrostomy for 6, 24, or 48 hrs . After each feeding period, 10(10) 14C Escherichia coli were infused intragastrically . In both experiments, the animals were killed 4 hrs after gavage, and mesenteric lymph nodes, spleen, liver, lungs, peritoneal fluid, and blood were harvested aseptically . MEASUREMENTS: For each tissue or fluid, the number of viable E . coli and radionuclide counts of the 14C E . coli were measured and the percentage of translocated bacteria that remained alive was calculated . MAIN RESULTS: In mice, 18 and 24 hrs of preburn starvation increased translocation only to the mesenteric lymph nodes, but it also enhanced bacterial killing in all tested tissues . Guinea pigs that were fed enterally for 6, 24, and 48 hrs postburn had significantly lower bacterial translocation in all tissues compared with animals infused with lactated Ringer's solution . Additionally, enhanced killing of translocating organisms was observed after 24 and 48 hrs of feeding . CONCLUSIONS: Starvation preburn has different consequences than starvation postburn on translocation and bacterial killing . Postburn enteral nutrition decreases the load of viable bacteria in the tissues via a double mechanism: an initial decreased translocation and a subsequent improved ability to kill bacteria that do translocate.

Can J Surg, 1994 Feb, 37(1), 23 - 8
Chronic, contained rupture of aortic aneurysms associated with vertebral erosion; Galessiere PF et al.; Chronic, contained rupture of aortic aneurysms is an important subset of ruptured aneurysms . Their presentation is unusual, and the diagnosis may be delayed . The associated vertebral erosion may contribute to the difficulty in diagnosis . The courses of three patients with chronic, contained rupture of an aortic aneurysm associated with vertebral erosion are presented . In each case the presentation was unusual and the initial diagnosis delayed . Computed tomography demonstrated the contained rupture and vertebral erosion in all cases . Microorganisms were cultured from all three aneurysms . Repair was successful in all cases . Contained rupture of an aortic aneurysm should be considered in older patients with unexplained back pain, and the possibility of this condition should not be ignored when there is a history of arthritic back pain or a radiograph suggestive of degenerative disease . Urgent surgical repair is indicated to prevent lethal, uncontrolled hemorrhage.

Infect Immun, 1994 Feb, 62(2), 639 - 43
Effect of tracheal cytotoxin from Bordetella pertussis on human neutrophil function in vitro; Cundell DR et al.; The infiltration of neutrophils which phagocytose and kill microorganisms is an important defense mechanism against infections of the airways . Bordetella pertussis is a human respiratory pathogen which colonizes ciliated epithelium, causing whooping cough . We have investigated the effects of the peptidoglycan fragment tracheal cytotoxin (TCT) of B . pertussis on human neutrophil function in vitro . TCT (10(-6) to 10(-8) M) was toxic for human neutrophils, as measured by lactate dehydrogenase release and levels of intracellular ATP . TCT (10(-9) to 10(-15) M) did not stimulate neutrophil migration or chemiluminescence and did not affect neutrophil phagocytosis . Incubation of neutrophils for 20 min with TCT (10(-9) to 10(-11) M) significantly inhibited (P < 0.05) their subsequent migration toward the chemotactic factor N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP; 10(-9) M) . Incubation of neutrophils for 20 min with TCT (10(-9) to 10(-15) M) significantly inhibited (P < 0.05) chemiluminescence stimulated by FMLP (10(-5) M) . TCT (10(-6) to 10(-12) M) did not stimulate interleukin-1 alpha production by neutrophils or serum complement activation by the alternate pathway . We conclude that TCT at concentrations of < 10(-8) M affects important neutrophil functions and at higher concentrations is toxic . TCT may therefore contribute to the survival of B . pertussis within the airways in vivo.

J Oral Maxillofac Surg, 1994 Feb, 52(2), 161 - 5; discussion 166
Autologous fibrin adhesive in mandibular reconstruction with particulate cancellous bone and marrow; Tayapongsak P et al.; Displacement of bone graft particles during their placement, neck flap closure, and insertion of the freeze-dried mandibular crib housing the graft to the glenoid fossa is a commonly encountered problem during major mandibular reconstruction with autogenous particulate cancellous bone and marrow . Autologous fibrin adhesive proved to be a solution as demonstrated in a series of 33 cases . In addition to adhesive and hemostatic properties, it helped the remodeling process begin about 50% earlier by providing the substratum for migration of mesenchymal cells, accelerating revascularization and migration of fibroblasts, stimulating the growth of both fibroblasts and osteoblasts, and slowing the multiplication of microorganisms . Bony incorporation and remodeling were detected radiographically at the fourth postoperative week compared with the eighth week in bone grafts without autologous fibrin adhesive.

Sangre (Barc), 1994 Feb, 39(1), 35 - 8
{Bone marrow granulomas}; Vijnovich Baron IA et al.; PURPOSE: To evaluate bone marrow granulomatous lesions in order to establish their etiology . MATERIAL AND METHODS: 2,250 bone marrow biopsies were studied during the period of March 1983-March 1991 . Granulomas and/or granulomatous lesions were found in 24 of them (1.06%) . A correlation between histological characteristics, special stains: PAS, Ziehl Neelsen and Grocott and cultures were done . Immunohistochemistry was done to evaluate B or T cell-lineage in 4 patients . RESULTS: The 24 patients were biopsied because of the clinical diagnosis of haematological and non-haematological neoplasias, infections, AIDS, sarcoidosis and fever of unknown origin . Bone marrow cellularity ranged from 20% to 75% (M: 49.8%) . Myeloid cells were increased in 54% of the cases . The number of granulomas ranged from 1 to 19 (M: 3.9) . The epithelioid cells were the predominant component in 66% of the cases . Of the 7 patients with non-Hodgkin's lymphoma, 4 had lymphomatous involvement with granulomatous pattern . These cases showed predominance of lymphoid cells and vessels in addition to epithelioid cells . CONCLUSION: We consider that in order to establish a relationship between infection and granuloma, the identification of a microorganism through a culture is a more reliable test . We couldn't find any morphological characteristic which allowed an etiologic diagnosis of bone marrow granulomas . In case of lesions with a great lymphocytic and vascular proliferation plus the presence of epithelioid cells and fibrosis, NHL with bone marrow involvement with a granulomatous pattern should be strongly considered.

Comput Appl Biosci, 1994 Feb, 10(1), 71 - 3
Integrated software for probabilistic identification of microorganisms; Maradona MP; A computer program has been designed to carry out microbial identification using probability matrices along with the Bayes theorem . When implementing the system the main considerations have been flexibility, user-friendliness and integration of identification coefficients and mathematical tests of matrices . The program has been developed in QuickBASIC for PC/MS-DOS operating systems and presents a menu-driven structure that aims to facilitate its use.

Biol Rev Camb Philos Soc, 1994 Feb, 69(1), 1 - 33
Cost of growth in cells and organisms: general rules and comparative aspects; Wieser W; In a crude fashion it can be said that metabolizable energy (M) is partitioned into metabolic work, paid for by 'oxidations' (R), and 'assimilation', i.e . production (P), so that M = R+P . However, a fraction of R is required to meet the expenses of production and if these expenses represent, Joule for Joule, a constant proportion of the amount produced, then Rt = Rm+cP, where Rt = total metabolic expenditures, Rm = metabolic expenditures for maintaining the non-producing organism, and cP = Rp = metabolic expenditures connected with the processes of production . The partitioning of metabolizable energy into R and P as well as into Rm and Rp may vary depending on the phylogeny and life-history of the species concerned and on ecological circumstances . Thus selection is expected to act on both ratios, R/P and Rm/Rp . By comparing the ratios P/(P+Rp) (the apparent efficiency of production) and Rp/P (the apparent metabolic cost of production) in different types of organisms, one finds that a value of P/(P+Rp) = 0.75, equal to 75% efficiency, 10 mgdbm/mmol ATP, and 16 mumolO2/mg dbm (when I mg identical to 22 J), can be used as a 'consensus value' for the average efficiency, or cost, of the transformation of metabolizable energy into production in a wide range of organisms, from bacteria to mammals . This value corresponds to about three times the theoretical cost of synthesizing the same amount of tissue on the basis of known biochemical principles . The reasons why the empirical costs of production are higher than the theoretical costs of synthesis by what appears to be a common factor may be quite different in bacteria, small ectothermic and large endothermic organisms . Deviations from the consensus value may be due to differences in energy density of the nutrients assimilated and the tissues synthesized . Further complications arise because of interactions between P, Rp, and Rm . In microorganisms the existence of a constant and a variable component of maintenance metabolism has been postulated, the latter decreasing with increasing rate of production . In small ectothermic metazoans, on the other hand, the nonlinear relationship between growth metabolism and growth rate has led to the speculation that above a critical value of Pg certain energy consuming functions of maintenance are suppressed and the energy thus gained used for fuelling growth processes . There is some evidence that, at least in ectothermic metazoans, the apparent cost of growth decreases with the rate of growth, reaching a low plateau of about 10 mumolO2/mgdbm at growth rates exceeding about 8 mgdbm/g/h.(ABSTRACT TRUNCATED AT 400 WORDS)

Semin Cancer Biol, 1994 Feb, 5(1), 77 - 90
Skin cancer and transgenic mice; Zinkel S et al.; At the outer surface of the body, the epidermis of skin forms a protective barrier to keep microorganisms out and essential body fluids in . This barrier is composed of one main cell type, the keratinocyte, which undergoes a precisely defined program of differentiation to produce a durable and renewable integument . The delicate balance between differentiation and proliferation is maintained by regulatory molecules and growth factors . In basal and squamous cell carcinomas of the skin, the balance between growth and differentiation goes awry, although the detailed pathways underlying these cancers remain to be elucidated . Transgenic mice provide the opportunity to precisely perturb growth factors in the skin in the context of a whole organism, leading to valuable insight into both appropriate and deranged growth . This article will review the biology and biochemistry of epidermal growth and differentiation, with emphasis on basal and squamous cell carcinomas and hyperproliferative diseases of the skin, and how recent transgenic research has been utilized to take a penetrating look into these issues.

Med Sci Sports Exerc, 1994 Feb, 26(2), 140 - 6
NK cell response to physical activity: possible mechanisms of action; Pedersen BK et al.; Natural killer (NK) cells are highly influenced by physical exercise . The possible important mechanisms behind exercise-induced changes in NK cell function are cytokines, hyperthermia, and stress hormones, including catecholamines, growth hormone, cortisol, and beta-endorphins . Infusion studies mimicking stress hormone levels in blood during exercise indicate that increased plasma-adrenaline accounts for at least part of the exercise-induced modulation of NK cell function . During moderate as well as severe acute exercise, the NK cell activity is enhanced, but severe exercise is followed by immunodepression, at least in part caused by prostaglandins . Elite athletes have at rest elevated NK cell activity . However, due to frequent severe exercise the NK cell function is often temporarily severely depressed . It is suggested that during the time of immunodepression microorganisms, especially virus, invade the host, whereby infections can be established . However, in those who perform regular moderate exercise the immune system will often be temporarily enhanced and this will protect these from infections.

Nihon Kyobu Shikkan Gakkai Zasshi, 1994 Feb, 32(2), 168 - 73
{A case of chronic necrotizing pulmonary aspergillosis effectively treated with miconazole inhalation}; Maeda T; A 63-year-old male was hospitalized due to persistent cough on August 19, 1991 . He was suspected to have pulmonary tuberculosis based on the findings of chest roentgenograms . He was therefore given anti-tuberculous drugs and antibiotics as of the first hospital day . Approximately two months later, he developed high fever, and the infiltrative shadows on his chest roentgenograms worsened . Therefore, he was readmitted to our hospital on October 31, 1991 . Despite the use of several antibiotics, his high fever persisted and the infiltrative shadows on chest roentgenography continued to worsen after admission . Although no pathogenic microorganisms were isolated, in spite of frequent sputum examinations, we strongly suspected pulmonary aspergillosis because serum precipitin antibody against aspergillus antigens was positive . Intravenous administration of miconazole was thus initiated and lead to reduction in the fever . The fever recurred but, after the start of miconazole inhalation, gradually diminished . Serum precipitin antibody subsequently became negative . We diagnosed this case as chronic necrotizing pulmonary aspergillosis based on the clinical course . It is often difficult to confirm the presence of aspergillus hyphae . Therefore, this disease should be suspected on the basis of serum precipitin antibody . In such cases, a therapeutic diagnosis should be attempted.

Clin Infect Dis, 1994 Feb, 18(2), 199 - 206
Lack of clinical benefit from subcutaneous tunnel insertion of central venous catheters in immunocompromised patients; Andrivet P et al.; To assess the efficacy of subcutaneous tunneling, we randomly designated 212 central venous catheters for tunneling (107 catheters) or for standard insertion (105 catheters) in 169 immunocompromised patients . The patients who received tunneled catheters (TCs) and the patients who received nontunneled catheters (NTCs) were similar with respect to age, gender, underlying disease, incidence of leukopenic episodes, receipt of blood product transfusions or parenteral nutrition, and medical care and attendants . The life span of catheters was 112.5 +/- 9.5 days in the TC group and 119 +/- 9 days in the NTC group (P = .5) . Clinically relevant bacteremia occurred in 26 cases in the TC group (0.22 episode per 100 catheter-days), a rate not significantly different from that in the NTC group (25 episodes; 0.20 episode per 100 catheter-days) . Catheter-related bacteremia was documented in seven cases and non-catheter-related bacteremia in five cases . In most instances, the precise origin of the septic episode could not be determined . Cutaneous infection and bacteremia were associated with the same microorganism in two cases in each group . Since the present study failed to demonstrate any clinical benefit of subcutaneous tunneling, such a procedure is no longer performed in our hospital.

J Periodontol, 1994 Feb, 65(2), 162 - 7
The influence of surface-free energy on supra- and subgingival plaque microbiology . An in vivo study on implants; Quirynen M et al.; The influence of surface free energy on supra- and subgingival plaque microbiology was examined in 9 patients with functional fixed prostheses supported by endosseous titanium implants . Two abutments (trans-mucosal part of the 2 stage implant) were replaced by either a new titanium abutment or a fluor-ethylene-propylene (FEP) coated abutment per subject . After 3 months of habitual oral hygiene, plaque samples were taken . Supragingival plaque was examined by means of differential phase-contrast microscopy, whereas for the subgingivial plaque additional analyses (DNA probes analysis, culturing) were performed . The subgingival samples were taken by paper-points and by scraping of the subgingival abutment surface . Differential phase-contrast microscopy showed a significant difference in plaque composition, especially when supragingival plaque was considered (P = 0.05) . FEP coated abutments frequently harbored more coccoid microorganisms, whereas spirochetes or motile organisms were only detected around titanium abutments . Subgingivally, the number of colony forming units (CFU) in paper-points was comparable for both types of abutments . If the to-the-abutment-adhering plaque was considered, the number of CFU was 5 times higher on the titanium abutments than on the FEP coated abutments . However, this difference did not reach a statistical level of significance (P = 0.38) . The DNA probe analysis of the subgingival plaque collected with paper-points showed a slightly higher frequency and concentration of perio-pathogens around the titanium abutments . However, the inter-substratum differences were smaller than the inter-subject differences . The latter seemed to be related to patient's dental status.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunol Today, 1994 Feb, 15(2), 67 - 74
Collectins: collagenous C-type lectins of the innate immune defense system; Holmskov U et al.; Collectins are humoral lectins found in mammals and birds . They are oligomers whose subunits comprise three polypeptide chains each containing a collagenous section and a C-terminal lectin domain . They are related structurally and functionally to the first component of the classical complement pathway, C1q, and seem to serve important roles in innate immunity through opsonization and complement activation . The lectin domains bind carbohydrates on microorganisms, while the collagenous regions are ligands for the collectin receptor on phagocytes and also mediate C1q-independent activation of the classical complement pathway.

J Clin Periodontol, 1994 Feb, 21(2), 76 - 85
Prevalence of periodontitis and suspected periodontal pathogens in families of adult periodontitis patients; Petit MD et al.; The aim of the present study was to investigate the prevalence of periodontopathic microorganisms and periodontal destruction in the spouses and children of adult periodontitis patients . For this study, 24 families were selected on the basis of one parent with severe periodontal breakdown and the presence of Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis and/or more than 30% Prevotella intermedia subgingivally . The clinical examination of both parents and children included pocket depth and clinical attachment loss (CAL) measurements . Samples for bacterial examination were obtained from the mucous membranes, the saliva and pockets . Pocket selection was based on the most advanced periodontitis situation found in a subject . The samples were cultured for the detection of A . actinomycetemcomitans, P . gingivalis and P . intermedia . By phase-contrast microscopy, the % of spirochetes and motile microorganisms was assessed . The number of children within each family varied between 1 and 3 . In total 49 children were investigated with a range in age of 3 months to 15 years . Results showed that under the age of 5 years, none of the children had CAL, whereas in the age group of 5-15 years, 26.5% had 1-5 sites in the primary and/or permanent dentition with 1-3 mm CAL . 3 of the spouses had no interproximal CAL . 16 of the 24 spouses had a light to moderate form of periodontitis, with at least one site with 1 to 4 mm CAL and 5 spouses had severe periodontal breakdown with sites showing at least 8 mm CAL . Spirochetes, motile microorganisms and P . intermedia were frequently present in all family members . 18 out of the 24 probands were positive for P . gingivalis . This organism was found once only in a 5-year-old boy and in 11 of the spouses . A . actinomycetemcomitans was detected in 13 probands; 5 children and 5 of the spouses were also positive for this bacterium . If a child harboured one of the periodontopathogens, at least 1 of the parents was also positive for that bacterium . This phenomenon may be due to transmission of microorganisms between family members . Comparison of the clinical data reported in the present study with similar clinical parameters from epidemiological studies of the Dutch population suggest that the spouses and children of adult periodontitis patients might be at relatively high risk of developing periodontal breakdown.

Appl Environ Microbiol, 1994 Feb, 60(2), 746 - 8
Recognition of chimeric small-subunit ribosomal DNAs composed of genes from uncultivated microorganisms; Kopczynski ED et al.; When PCR was used to recover small-subunit (SSU) rRNA genes from a hot spring cyanobacterial mat community, chimeric SSU rRNA sequences which exhibited little or no secondary structural abnormality were recovered . They were revealed as chimeras of SSU rRNA genes of uncultivated species through separate phylogenetic analysis of short sequence domains.

Nippon Rinsho, 1994 Feb, 52(2), 439 - 45
{Intractable bacterial infections in the nervous system}; Motohiro T et al.; It is not exaggeration to say that infectious meningitis is most often seen among infections of the nervous system caused by various microorganisms, in which viruses are main causative pathogens . Infectious meningitis due to bacteria includes purulent one with acute progress, tuberculous and fungal ones which are representative for subacute meningitis . They can not be easily treated . As brain abscess is similar to them, diagnosis and chemotherapy on these four diseases are briefly summarized here . It is needless to say that the prognosis is influenced by early diagnosis and how fast appropriate chemotherapy is started in all four diseases . Dexamethasone therapy should be tried in purulent meningitis in order to decrease hearing disturbance which is unable to be prevented by chemotherapy.

J Prosthet Dent, 1994 Feb, 71(2), 154 - 8
Microbial contamination in four commercially available denture adhesives; Gates WD et al.; Four brands of commercially available powder denture adhesives were tested for microbial contamination . Sterile Petri plates that contained either brain-heart infusion (BHI) or Sabouraud's (SAB) agar were inoculated with 0.5 gm samples of each adhesive . The BHI plates were incubated aerobically and anaerobically at 35 degrees C and the SAB plates aerobically at 30 degrees C for 2 weeks . The sterility of these procedures was confirmed by incubating uninoculated control plates . All bottles of powder denture adhesive tested contained microorganisms . Both bacterial and fungal growth were noted . The containers of adhesive were then subjected to 10 minutes of microwave energy (650 W) to sterilize the adhesive material . After retesting, any bottles still contaminated were subjected to additional 10 minutes of microwave exposure and then retested . Seven of 24 bottles still showed evidence of microbial contamination after exposure to microwave energy . Of the seven bottles, five were of one brand . A Fisher's exact test showed significant differences in the percentage of contaminated samples between that and the other brands (p < 0.05) . Microwave energy reduced microbial contamination in all samples but failed to completely sterilize seven of 24 samples.

Am J Trop Med Hyg, 1994 Feb, 50(2), 219 - 28
An ultrastructural study of vertical transmission of Rickettsia tsutsugamushi during oogenesis and spermatogenesis in Leptotrombidium pallidum; Urakami H et al.; Rickettsia tsutsugamushi in Leptotromibidium pallidum was observed by electron microscopy and rickettsiae were found in the various tissues and organs of both larvae and adults . Budding of rickettsiae, a manner of release from the host cells, was observed only in the rudiments of the reproductive organs in larvae . Oogonia and maturing oocytes in adult females and eggs after oviposition contained the microorganisms . In adult males, rickettsiae were also found in the spermatogonia, spermatocytes, and spermatids in the early stage of spermatogenesis, but were eliminated from these cells during maturation . Only the maturing spermatids, but not the eliminated rickettsiae, migrated to another rickettsia-free area of the testis, resulting in the separation of spermatids from rickettsiae and in the production of rickettsia-free spermatophores . Based on these observations, the mechanism of vertical transmission of the rickettsiae to the progeny occurs only in the female parents . Most rickettsiae in the somatic cells of larvae and adults were coccoid, but some rickettsiae in the ovary and the testis of adult mites showed bacillary forms and were enveloped by a membrane of unknown origin.

Insect Mol Biol, 1994 Feb, 3(1), 27 - 33
Molecular identification of rickettsia-like microorganisms associated with colonized cat fleas (Ctenocephalides felis); Higgins JA et al.; Cat fleas (Ctenocephalides felis) from eight commercial flea colonies from various regions of the USA were examined by selective PCR amplification, and subsequent restriction digest analysis and Southern hybridization of PCR products, for the presence of a rickettsia-like organism (ELB agent) . These flea colonies were either started with fleas from one supplier (EL Labs), in which ELB agent was first identified, or were started with fleas from stray cats and dogs and later came into contact with ELB-infected fleas . Infection rates in the colonies ranged from 43% to 93% . The successful propagation of ELB agent in these colonies may be due to efficient trans-stadial and transovarial transmission . While ELB agent has recently been identified in blood from human murine typhus cases, attempts to infect mammalian cells and SCID mice with flea isolates were unsuccessful.

Acta Virol, 1994 Feb, 38(1), 31 - 3
Possible significance of antibodies to Legionella pneumophila in HIV-1 infected patients with acute respiratory illness; Del Prete R et al.; Eighty-six serum samples from 52 HIV-1 infected patients with complicating pneumonia illness were assayed for the presence of antibodies to Legionella pneumophila . In 25 of these patients Pneumocystic carinii has been previously diagnosed . Among all patients investigated only 4 had antibodies to L . pneumophila of significant titer of 128 . In one patient L . pneumophila was demonstrated coexisting with P . carinii . Despite of a small proportion of patients with a significant titer of antibodies against L . pneumophila, the presence of this microorganism should be carefully investigated in AIDS patients with complicating pneumonia especially when the aetiological diagnosis is not defined; the reason is to improve the therapeutic treatment.

Med Hypotheses, 1994 Feb, 42(2), 81 - 8
Chronic infections from the perspective of evolution: a hypothesis; Ngu VA; No satisfactory explanation has so far been given for the persistence in the body sometimes, of various microorganisms-bacteria, parasites, fungi and viruses-in spite of their foreign antigens and a competent immune system . It has been proposed as an explantation that these microorganisms, in the course of evolution, have concealed their true antigens from the immune system . Free living microorganisms concealed their true antigens when the heat of the sun, with the threat of dehydration, induced the development in surviving mutants of a lipid coat to reduce surface water losses . This coat enveloped the microorganisms, concealing their true antigens . Viruses that cause chronic infections concealed their true antigens beneath a viral envelope derived from host cell . Exposing the true antigens on microorganisms and viruses with suitable lipid solvents and re-introducing the microorganisms and viruses so treated into the host as a kind of vaccine, should provoke a new immune response effective in eliminating the pathogens concerned from the body and in preventing future infections . In this way, pathogens could be used to treat and prevent certain infectious diseases . The above procedure should have significant benefits for human and animal health.

Med Hypotheses, 1994 Feb, 42(2), 133 - 4
Short note: possible role of macrophage metabolic products including quinolinic acid and neopterin in the pathogenesis of inflammatory brain diseases; Rabinoff M; It is hypothesized that macrophage metabolic products, including the possible neurotoxic NMDA receptor agonist quinolinic acid, and neopterin, may play a role in the pathogenesis of inflammatory brain diseases . It is suggested that the production of neopterin may have physiological roles, including to inhibit folate synthesis in intracellular pathogenic microorganisms and to inhibit viral nucleic acid synthesis . The possible role of excess neopterin production during chronic infection in the pathogenesis of inflammatory brain diseases is discussed.

Plant Cell, 1994 Feb, 6(2), 265 - 75
Light regulation of chlorophyll biosynthesis at the level of 5-aminolevulinate formation in Arabidopsis; Ilag LL et al.; 5-Aminolevulinic acid (ALA) is the universal precursor of tetrapyrroles, such as chlorophyll and heme . The major control of chlorophyll biosynthesis is at the step of ALA formation . In the chloroplasts of plants, as in Escherichia coli, ALA is derived from the glutamate of Glu-tRNA via the two-step C5 pathway . The first enzyme, Glu-tRNA reductase, catalyzes the reduction of Glu-tRNA to glutamate 1-semialdehyde with the release of intact tRNA . The second enzyme, glutamate 1-semialdehyde 2,1-aminomutase, converts glutamate 1-semialdehyde to ALA . To further examine ALA formation in plants, we isolated Arabidopsis genes that encode the enzymes of the C5 pathway via functional complementation of mutations in the corresponding genes of E . coli . The Glu-tRNA reductase gene was designated HEMA and the glutamate 1-semialdehyde 2,1-aminomutase gene, GSA1 . Each gene contains two short introns (149 and 241 nucleotides for HEMA, 153 and 86 nucleotides for GSA1) . The deduced amino acid sequence of the HEMA protein predicts a protein of 60 kD with substantial similarity (30 to 47% identity) to sequences derived from the known hemA genes from microorganisms that make ALA by the C5 pathway . Purified Arabidopsis HEMA protein has Glu-tRNA reductase activity . The GSA1 gene encodes a 50-kD protein whose deduced amino acid sequence shows extensive homology (55 to 78% identity) with glutamate 1-semialdehyde 2,1-aminomutase proteins from other species . RNA gel blot analyses indicated that transcripts for both genes are found in root, leaf, stem, and flower tissues and that their levels are dramatically elevated by light . Thus, light may regulate ALA, and hence chlorophyll formation, by exerting coordinated transcriptional control over both enzymes of the C5 pathway.

Bioseparation, 1994 Feb, 4(1), 29 - 38
Ultrasound enhanced phase partition of microorganisms; Allman R et al.; Aqueous two-phase partition is an established technique for the separation of many biological particles or solutes . Similarly, ultrasound is finding application in the harvesting of cell populations . We have combined the two methodologies to produce an elegant technique for separating and concentrating biological particles or solutes in an enclosed environment which is non-destructive and minimally perturbing to the objects being separated . Megahertz frequency ultrasonic standing wave fields produced either axially or radially from piezo-ceramic transducers dramatically reduce the time for completion of partition to about 1 min as demonstrated using Saccharomyces cerevisiae and Escherichia coli . The system described is competitive with established methods of cell separation and concentration.

Free Radic Biol Med, 1994 Feb, 16(2), 275 - 82
Expression of manganese superoxide dismutase promotes cellular differentiation; St Clair DK et al.; Manganese superoxide dismutase (MnSOD) is a nuclear encoded mitochondrial matrix enzyme that scavenges toxic superoxide radicals . It has been shown that increased generation of reactive oxygen species is associated with the differentiation of microorganisms . To test the hypothesis that the ability of mitochondrial superoxide dismutase to neutralize a cellular hyperoxidant state is important for differentiation of mammalian cells, we examined the effect of transfection of MnSOD into mouse embryo fibroblasts on cellular differentiation . C3H10T1/2 cells served as a model for differentiation because these cells can be triggered to differentiate into myoblasts, adipocytes, and chondrocytes by treatment with 5-azacytidine . In this report, myoblast differentiation was defined by the presence of multinucleated cells, appearance of Z-bands, and expression of actin and desmin in the differentiated cells . Transfection of MnSOD gene was found to greatly enhance differentiation of C3H10T1/2 cells into myoblasts by 5-azacytidine . This result identifies MnSOD as an important factor for cell differentiation and supports a role for reactive oxygen species in the process of cellular differentiation.

Trends Neurosci, 1994 Feb, 17(2), 62 - 71
Chemosensory transduction in eukaryotic microorganisms: trends for neuroscience?
Van Houten J.
It might appear curious to read about yeast, slime molds and protozoa in a journal dedicated to neuroscience . However, despite their distinct lack of synapses, eukaryotic microorganisms hold a wealth of information relevant to the signal-transduction pathways that underly activity in neuronal receptor cells, particularly those subserving the chemical senses . Microorganisms are sensitive to chemical stimuli from their environment and thus have similarities to receptor neurons of the olfactory system and the taste bud . Here, we introduce receptors, second messengers and effectors responsible for chemosensory signal transduction in yeast mating, sea-urchin spermatozoan chemotaxis, slime-mold aggregation and development, and ciliate chemoresponses.

Biochem Biophys Res Commun, 1994 Jan 28, 198(2), 682 - 92
The exon-intron structure and chromosomal localization of the mouse macrophage mannose receptor gene Mrc1: identification of a Ricin-like domain at the N-terminus of the receptor; Harris N et al.; The macrophage mannose receptor is a transmembrane protein that is expressed on the surface of mature macrophages . The ectodomain of the receptor contains multiple domains, eight of which belong to the calcium-dependent C-type lectin family . The mannose receptor binds to carbohydrate polymers that have a high content of mannose . This property allows this protein to function as a phagocytic receptor that participates in first-line host defense against invading microorganisms . In this paper we describe the intron-exon structure of the mouse macrophage mannose receptor gene which was found to span at least 70 kilobases . We also report the localization of this gene, termed Mrc1, to mouse Chromosome 2 . Like its human counterpart, Mrc1 contains 30 exons and 29 introns . A protein module that resembles a subdomain of the B chain of the plant lectin Ricin has been found within the N-terminal cysteine-rich domain of the mannose receptor.

Biochim Biophys Acta, 1994 Jan 18, 1217(1), 97 - 100
Organization and nucleotide sequence of the secE-nusG region of Streptomyces griseus; Miyake K et al.; The nusG genes of Streptomyces griseus and Streptomyces coelicolor A3(2) were cloned by the DNA-probing method with synthetic oligonucleotides designed on the basis of the nucleotide sequence of the nusG gene of Streptomyces virginiae . The amino acid sequences of the NusG proteins deduced from the nucleotide sequences showed significant homologies to those from a variety of microorganisms . Nucleotide sequence analysis of the region upstream of the nusG gene of S . griseus revealed the presence of the secE gene, suggesting that secE and nusG are organized as an operon as is found in other microorganisms.

CMAJ, 1994 Jan 15, 150(2), 177 - 85
Helicobacter pylori infection as a cause of gastritis, duodenal ulcer, gastric cancer and nonulcer dyspepsia: a systematic overview; Veldhuyzen van Zanten SJ et al.; OBJECTIVE: To evaluate current evidence for a causal relation between Helicobacter pylori infection and gastritis, duodenal ulcer, gastric cancer and nonulcer dyspepsia . DATA SOURCES: A MEDLINE search for articles published in English between January 1983 and December 1992 with the use of MeSH terms Helicobacter pylori, gastritis, duodenal ulcer, gastric cancer, dyspepsia and clinical trial; abstracts were excluded . Six journals and Current Contents were searched manually for pertinent articles published in that time frame . STUDY SELECTION: Original studies with at least 25 patients, case reports and reviews that examined the relation between H . pylori and the four gastrointestinal disorders; 350 articles were on gastritis, 122 on duodenal ulcer, 44 on gastric cancer and 96 on nonulcer dyspepsia . DATA EXTRACTION: The quality of the studies was rated independently on a four-point scale . The strength of the evidence was assessed using a six-point scale for each of the eight established guidelines for determining a causal relation . DATA SYNTHESIS: There was conclusive evidence of a causal relation between H . pylori infection and histologic gastritis . Koch's postulates for the identification of a microorganism as the causative agent of a disease were fulfilled for H . pylori as a causative agent of gastritis . There was strong evidence that H . pylori is the main cause of duodenal ulcers not induced by nonsteroidal anti-inflammatory drugs, but all of Koch's postulates were not fulfilled . There was moderate epidemiologic evidence of an association between chronic H . pylori infection and gastric cancer . There was a lack of convincing evidence of a causal association between H . pylori and nonulcer dyspepsia . CONCLUSIONS: The evidence supports a strong causal relation between H . pylori infection and gastritis and duodenal ulcer and a moderate relation between such infection and gastric cancer . Further studies are needed to clarify the role of H . pylori in these disorders . Thus far, there is no evidence of a causal relation between H . pylori and nonulcer dyspepsia.

J Biol Chem, 1994 Jan 7, 269(1), 711 - 5
Osteopontin inhibits induction of nitric oxide synthase gene expression by inflammatory mediators in mouse kidney epithelial cells; Hwang SM et al.; We report that osteopontin (OPN), a secreted, Arg-Gly-Asp-containing phosphoprotein expressed at high levels in the kidney, suppresses nitric oxide (NO) synthesis induced by the inflammatory mediators gamma-interferon and lipopolysaccharide in primary mouse kidney proximal tubule epithelial cells . Northern blot and immunofluorescence analyses of inducible nitric oxide synthase (iNOS) expression revealed that the inflammatory mediators increased iNOS mRNA and protein levels . Recombinant human OPN (purified from both mammalian cells and from Escherichia coli) inhibited this response by a process that was blocked by anti-OPN antiserum and by the peptide GRGDS, but not GRGES . The data suggest that inhibition of NO synthesis by OPN in these kidney cells is mediated by an integrin, possibly the alpha v beta 3 integrin, which is known to be an OPN receptor . NO is believed to control blood flow through the glomerulus, regulating salt and water balance, and to be important as a defense against tumor cells and infecting microorganisms . The ability of OPN to inhibit the induction of iNOS suggests that OPN may be an important regulator of the NO signaling pathway and NO-mediated cytotoxic processes.

Folia Microbiol (Praha), 1994, 39(6), 481 - 4
Phytase from Aspergillus niger; Volfova O et al.; 132 microorganisms, isolates from soil and decayed fruits, were tested for phytase production . All isolates intensively producing active extracellular phytase were of fungal origin . The most active fungal isolates with phytase activity were identified as Aspergillus niger . At the end of the growth phase, the extracellular phytase activity produced by A . niger strain 92 was 132 nkat/mL, with strain 89 it was 53 nkat/mL . In both strains the extracellular enzyme activity exhibited two marked activity optima at pH 1.8 and 5.0 and a temperature optimum at 55 degrees C.

J West Soc Periodontol Periodontal Abstr, 1994, 42(3), 77 - 80
Human dental plaque formation on plastic films . A quantitative SEM study; Brecx M et al.; The initial colonization of bacteria in previously clean teeth or artificial surfaces inserted in mouth has been reported to occur at various periods of time . Ronstrom et al., using light microscopy, saw that bacteria were present 10 seconds after prophylaxis . Bacterial culture studies have shown that microorganisms associated with the surface coating on tooth surfaces appeared within minutes after prophylaxis . Furthermore, Ronstrom et al . noted that the number of bacteria increased over a period of four hours . In contrast, ultrastructural investigations of early plaque have demonstrated bacterial colonization only within the first two hours of plaque development in a few samples obtained on a smooth surface and in most samples on a rough surface . However, microorganisms have been found regularly after four hours of plaque accumulation in subjects with healthy gingiva . The aim of the present investigation was to determine the earliest occurrence of bacterial colonization in situ and to observe the pattern of the initial formation of human dental plaque.

J Bacteriol, 1994 Jan, 176(2), 388 - 94
Rickettsial relative associated with male killing in the ladybird beetle (Adalia bipunctata); Werren JH et al.; A cytoplasmically inherited microorganism associated with male killing in the two-spot ladybird beetle, Adalia bipunctata, is shown to be closely related to bacteria in the genus Rickettsia . Sequencing of a PCR-amplified product of the 16S genes coding for rRNA (16S rDNA) shows the organism associated with male killing in ladybirds to share a common ancestry with the Rickettsias relative to other genera (e.g., Anaplasma, Ehrlichia, and Cowdria) . The rickettsial 16S rDNA product is found in four strains of ladybird beetle showing male embryo lethality and is absent from two uninfected strains and an antibiotic-cured strain . In addition, a revertant strain that had naturally lost the male-killing trait failed to amplify the rickettsial 16S rDNA product . Use of PCR primers for a 17-kDa protein antigen which is found only in rickettsias also resulted in an amplified product from infected strains . Uninfected, cured, and revertant strains and insect species infected with related bacteria (cytoplasmic-incompatibility bacteria from Nasonia wasps) failed to amplify the product . Discovery of a close relative of rickettsias associated with sex ratio distortion in insects has implications for the evolution and population dynamics of this bacterial genus.

Chest, 1994 Jan, 105(1), 224 - 8
Risk factors for early onset pneumonia in trauma patients; Antonelli M et al.; STUDY OBJECTIVES: The aim of the study was to identify risk factors for early onset pneumonia (EOP) in trauma patients, in order to seek possible intervention strategies . STUDY POPULATION: Participants included 124 consecutive trauma patients admitted to a general intensive care unit (ICU) of a university hospital from December 1990 to February 1992 inclusive . DATA COLLECTION: The following data were prospectively collected for each patient: demographics, severity of trauma according to the abbreviated injury scale (AIS), severity of coma according to the Glasgow coma scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and mechanical ventilation . All patients were monitored daily during the ICU stay for the onset of pneumonia, sepsis syndrome, septic shock, and adult respiratory distress syndrome (ARDS) . Criteria for the diagnosis of pneumonia were: core temperature of greater than 38.3 degrees C, a WBC count of 10,000 cells/mm3, purulent tracheobronchial secretions, a worsening of pulmonary gas exchange, and persistent pulmonary infiltrates . All patients with suspected pneumonia underwent quantitative bronchoalveolar lavage (BAL) as well as blood cultures; BAL cultures were considered positive when they showed bacterial growth greater than 1 x 10(5) colony-forming unit (cfu)/ml, or less than 10(5), but with the same microorganism isolated in blood cultures . Pneumonia occurring within the first 96 h after trauma was considered EOP . DATA ANALYSIS: A stepwise logistic regression analysis was carried out in order to identify factors independently associated with an increased risk of EOP and late onset pneumonia (LOP) . RESULTS: Overall mortality was 43.5 percent: mortality increased by age and AIS score . Forty one patients (33.1 percent) developed pneumonia: 26 (63.4 percent) were EOP and 15 (36.6 percent) were LOP . In the univariate analysis, an age greater than 40 years, the presence of pulmonary contusion, AIS of more than 4 for thorax and of more than 9 for abdomen, and the absence of mechanical ventilation (MV) during the first 4 days of hospitalization or MV lasting less than 24 h were significantly associated with an increased risk of acquiring EOP . Logistic regression analysis showed that the strongest risk factor for EOP was a combined severe abdominal and thoracic trauma, which increased the risk of EOP by 11 times; an age of more than 40 years and MV of less than 24 h during the first 4 days of hospitalization were also independent risk factors for EOP . Factors associated with LOP were an AIS score of more than 4 for abdomen and a length of MV of more than 5 days . CONCLUSION: In a trauma population, a combined severe abdominal and thoracic trauma represents a major risk factor for EOP . Mechanical ventilation administered during the first days after trauma seems to reduce the risk of EOP . As reported in previous studies, mechanical ventilatory support lasting more than 5 days is associated with an increased risk of LOP.

Ann Biol Clin (Paris), 1994, 52(1), 49 - 52
Clinical relevance of IgG subclass deficiencies; Morell A; Patients with primary or secondary IgG subclass deficiencies suffer from infections due to encapsulated microorganisms such as H influenzae and pneumococci . In addition to relapsing infections, some patients with primary subclass deficiencies may have autoimmune disorders . The best characterized defect in IgG2 deficiency, either isolated or combined with IgG4 deficiency . It is frequently associated with IgA deficiency or with ataxia telangiectasia . IgG1 deficiency occurs mostly in combination with disturbances of other immunoglobulin isotypes, and probably represents a form of common variable immune deficiency . Decreased IgG3 levels were reported in association with lung dysfunction and viral diseases . Except in IgG1 deficiency, total IgG serum levels in primary as well as secondary IgG subclass deficiency states may be normal or even increased . It is assumed that IgG subclass deficiencies represent an indicator of more basic immunologic abnormalities . There is evidence that antibody defects correlate better with the clinical symptoms than the total serum IgG subclass concentrations . In patients with severe recurrent infections and IgG subclass deficiency, intravenous immunoglobulin treatment at dosages of 0.3 to 0.4 g/kg body weight every 3-4 weeks is indicated.

Acta Vet Scand, 1994, 35(1), 93 - 8
Mycoplasma hyorhinis in the etiology of serositis among piglets; Friis NF et al.; In a study on the involvement of Mycoplasma hyorhinis in serositis of piglets, 26 routine diagnostic animals, 3-7 weeks old, with distinct serofibrinous lesions in the pericardial, pleural and peritoneal cavities were examined . M . hyorhinis was isolated in 9 cases, non-haemolytic Escherichia coli in another 9 cases and in 4 cases both species were found . Neither of the microorganisms were found in the remaining 4 cases . The presence of M . hyorhinis in the serous cavities in the absence of non-haemolytic E . coli was always accompanied by a diagnosis of other disease conditions, mainly of the respiratory tract . In the cases infected with non-haemolytic E . coli complicating problems were absent . The pathogenicity of M . hyorhinis was further studied by inoculation of 2 young pigs in which the typical serofibrinous lesions of the serous cavities were produced . It therefore appears that M . hyorhinis can be regarded as a cause of polyserositis in piglets; under field conditions, however, the synergistic presence of other debilitating syndromes appears necessary for its haematogenous spread from the respiratory tract to the serous cavities.

Mikrobiologiia, 1994 Jan-Feb, 63(1), 86 - 9
{Distribution in the genomes of microorganisms of fragments homologous to cDNA of chicken pro-alpha1(1) collagen}; Nuraminskaia MV et al.; Southern-analysis of genomic DNAs from 14 yeast species (Ascomycetes and Basidiomycetes) with alpha 1(1) chicken collagen cDNA coding for triple-helical domain as a probe, has shown that presence of genomic fragment, homologous to collagen genes of higher eucaryotes, is characteristic for yeasts . In bacterial genomes such fragments are revealed quite rarely . No collagen-like sequences has been found in known yeast proteins by computer-analysis.

Mikrobiologiia, 1994 Jan-Feb, 63(1), 5 - 16
{Physiologic and physico-chemical mechanisms of the resistance of microorganisms to freezing and drying}; Volkov VIa; The influence of osmotic stress and temperature on physiologo-biochemical state of microbial cells intended for freeze-drying has been analysed . Molecular mechanisms of cryo- and xeroprotective effect of protectors are dealt with in the paper.

Mikrobiologiia, 1994 Jan-Feb, 63(1), 145 - 51
{Sorption capacity of microbial biomass with respect to various radionuclides}; Khovrychev MP et al.; Biosorption capacity of different microorganisms to uptake 90Sr, 137Cs and 239Pu radionuclides from aqueous solution was investigated . Distribution coefficients of the above-mentioned radionuclides were determined as well as their dependence upon sorption conditions and pretreatment of microbial biomass . The possibility to use of the biomass of some microbial strains for recovery Sr, Cs, Pu from ultra-dilute solutions was demonstrated.

Nutr Hosp, 1994 Jan-Feb, 9(1), 18 - 26
{The contamination of enteral nutrition in critical patients}; Lalueza Broto MP et al.; Some previous studies have shown that administration of contaminated enteral diets may produce nosocomial infections in critical patients . There is a series of factors in these patients which may enhance the risk of clinical complications deriving from the administration of enteral nutrition (EN) contaminated by microorganisms (alteration of the immunological state, increased stomach pH, reduced intestinal motility, reduced mucosa production, etc.) . This study examines EN contamination in critical patients admitted to the ICU of the Hospital Universitario de Traumatologia y Rehabilitacion de las C . S . Vall d'Hebron, suffering from cranial-encephalic traumatism and/or multiple traumatism . The data made it possible to create a working design which takes account of factors which may increase the risk of EN contamination . The work was done in three phases, involving different handling procedures (Phase 1, Phase 2 and Phase 3) . The results of the three studies made it possible to describe a working method in which the following points are outstanding: handwashing with antiseptic soap prior to handling the EN, avoidance of reuse of containers (if necessary) for more than 24 hours, not to exceed 8 hours' perfusion of EN previously handled, and not to wash the container prior to adding new quantities of EN.

Can J Infect Control, 1994 Spring, 9(1), 5 - 8
Minimizing the risk of Q fever in the hospital setting; Perry S et al.; Q fever is caused by a rickettsial microorganism (Coxiella burnetii) harboured in sheep . The highest concentration of organisms are found in birth products . It is a very contagious organism which humans can contract by inhaling aerosolized organisms . Most commonly it leads to an acute 'flu-like illness . Rarely, chronic disease with endocarditis is fatal . Infected patients should be treated with tetracyclines or chloramphenicol . A number of outbreaks have been reported in hospital and research settings . Because of the fear of patients and staff contracting Q fever, Hospital Research Review Boards have increasingly resisted the presence of sheep in medical facilities . The authors have reviewed the circumstances leading to these outbreaks and believe researchers can minimize the risk of Q fever . The most important precautions are to use sheep only from Q fever controlled flocks and, depending on the nature of the research, only male sheep.

Trends Microbiol, 1994 Jan, 2(1), 10 - 4
Binding and internalization of microorganisms by integrin receptors; Isberg RR et al.; Many microbial pathogens bind host-cell integrin receptors . These interactions are promoted either by a host protein binding the microorganism or by a surface-localized ligand encoded by the pathogen . Attachment facilitates extracellular adhesion of the microorganism or internalization by the host cell.

CLAO J, 1994 Jan, 20(1), 32 - 6
Contamination of disinfection solution bottles used by contact lens wearers; Collins M et al.; We investigated the contamination of disinfection solution bottles after 2 weeks of patient use . Forty-four subjects participated in the study and each used three soft lens care systems (cross-over study) . The order in which the three care systems were dispensed was randomized to eliminate systematic bias . Sixteen subjects used only one of the systems (disinfection solutions) over three consecutive 2-week periods (reliability study) . Contamination of the disinfection solution bottles occurred in 12 of the 180 bottles sampled (7%), and the level of contamination of these bottles ranged up to 10(5) colony forming units per milliliter . A wide range of microorganisms was identified in these positive samples, many of which were potential ocular pathogens . None of the subjects in the study (n = 60) showed contamination in more than one of the three solution bottles sampled, suggesting that the phenomenon was not strongly patient specific . The rate of contamination of disinfection solution bottles was not influenced by contact lens wearing experience (i.e., familiarity with care procedures), by the time of year (season) at which the samples were collected, or by the subjects' compliance with hand washing . However, among the 44 subjects in the cross-over study, the rate of contamination of disinfection solution bottles was influenced by the type of disinfection solution.

Zentralbl Hyg Umweltmed, 1994 Jan, 195(2), 111 - 20
{The efficiency of sterilization methods for different soils}; Stroetmann I et al.; Three different soil types (two sandy materials and one till soil type) were sterilized with 14 different sterilization methods or variations . The cation-exchange capacity and specific surface of the soil samples were chosen as control parameters of physico-chemical modifications in the soils . Incubation of soil samples in the presence of Na-azide and HgCl2, in addition to tyndallization and fractionated heating of soil lead to a significant reduction of microorganisms . UV radiation and alternating freezing and thawing of soil had no influence on the number of microorganisms . The application of mercury-II-chloride did not lead to the expected sterilization, especially with till . A sterilization of soil is possible by using formaldehyde and ethylene oxide gassing, in addition to autoclaving and gamma radiation . No microorganisms could be detected in the soils after application of these sterilization methods . The cation exchange capacity of the soils was only slightly influenced with these methods . The use of gamma radiation seems to be the best method for sterilization of soils.

World Health Forum, 1994, 15(1), 69 - 71
Contaminated food, a hazard for the very young; Motarjemi Y et al.; Contaminated food is responsible for much diarrhoeal disease in young children, yet the education of mothers and care-givers about the preparation of food under hygienic conditions tends to be neglectedPIP: Breast milk is no longer sufficient to meet the nutritional requirements of infants aged 4-6 months; thus, during weaning, complimentary foods should be introduced gradually . At this time, infants are at increased risk of getting diarrhea from food-borne pathogens resulting in reduced food intake and loss of nutrients through vomiting and fever . Diminished immunological resistance to infections causes as estimated 13 million fatalities a year among children under 5 years of age as a result of infectious diseases and malnutrition . In developing countries, preparation of weaning foods under unhygienic conditions causes up to 70% of diarrheal cases . Pathogenic strains of Escherichia coli account for up to 25% of diarrhea episodes . The sources of food contamination are night soil, polluted water, files and other pests, domestic animals, dirty utensils and pots, unwashed hands, and dust . Pathogenic bacteria can multiply if the food is prepared several hours before consumption and stored at temperatures favoring the growth of microorganisms and/or production of toxins . Insufficient cooking or reheating can also facilitate bacterial growth . Sociocultural and economic factors contribute to risks, such as short supply of food; maternal ignorance about the link between diarrhea and improper food handling; unsafe water supplies and lack of sanitation with increased risk of food contamination; shortage of fuel for cooking and lack of refrigeration; and insufficient time for food preparation . The World Health Organization Golden Rules for Safe Food Preparation need to be observed . Food should be thoroughly cooked and fed to infants once it is cool enough; food should not be stored where there are no facilities for storage below 10 degrees Celsius or for keeping food at or above 60 degrees Celsius . Mothers should be advised about food safety within the framework of educational programs .

Pharm Res, 1994 Jan, 11(1), 160 - 74
Pharmacokinetic analysis of in vivo metabolism of amino acid or dipeptide conjugates of salicylic acid in rabbit intestinal microorganisms; Nishida K et al.; We analyzed the pharmacokinetics of salicylic acid (SA)-amino acid (alanine, glutamic acid, methionine, and tyrosine) or SA-dipeptide (glycylglycine) conjugates in rabbits, by using a model that takes into account the metabolism of prodrug to SA by intestinal microorganisms and, also, by model-independent analysis . The blood concentration profiles of these prodrugs and released SA following intracecal and oral administration to rabbits were obtained previously (Nakamura et al., J . Pharm . Pharmacol., 44, 295-299, 1992; Chem . Pharm . Bull., 40, 2164-2168, 1992; Int . J . Pharm., 87, 59-66, 1992; J . Pharm . Pharmacol., 44, 713-716, 1992) . First, the overall in vivo behavior was evaluated by statistical moment analysis . Next, the blood concentration profiles of prodrug and SA following intracecal and oral administration were simultaneously fitted to the above model . In general, good agreement was observed between fitted lines and experimental data for every prodrug, suggesting the validity of this model . The obtained parameters characterized the difference in the rate of metabolism and absorption among the prodrugs . Lower absorbability and enhanced hydrolysis rate of the prodrug lead to prolonged blood concentration of SA.

J Antibiot (Tokyo), 1994 Jan, 47(1), 54 - 63
Overproduction of the acyl carrier protein component of a type II polyketide synthase stimulates production of tetracenomycin biosynthetic intermediates in Streptomyces glaucescens; Decker H et al.; The development of microorganisms with improved antibiotic production is an important goal in the commercialization of new pharmaceuticals or in lowering the cost of established drugs . We report a way to achieve this for biosynthetic intermediates of an antibiotic made by the polyketide pathway whose earliest steps involve a Type II multienzyme complex . Introduction of the tcmKLM beta-ketoacyl: ACP synthase and acyl carrier protein (ACP) genes or just the tcmM ACP gene into the tetracenomycin (Tcm) C-producing Streptomyces glaucescens wild-type strain, or its tcmN or tcmO blocked mutants, on high copy vectors under the control of strong promoters caused a 2 to 30-fold overproduction of Tcm D3 and some other biosynthetic intermediates (or shunt products) and a 25 to 30% increase in Tcm C production relative to the control strains carrying the plasmid vector only . However, Tcm C production was not greater than that obtained with the vector-free wild-type strain . The unexpected effect of increased ACP on Tcm D3 production suggests that the level of this protein can influence either the activity or level of the three other components of the Tcm polyketide synthase.

Biometals, 1994 Jan, 7(1), 3 - 8
Ferric reductases or flavin reductases?
Fontecave M, Coves J, Pierre JL.
Assimilation of iron by microorganisms requires the presence of ferric reductases which participate in the mobilization of iron from ferrisiderophores . The common structural and catalytic properties of these enzymes are described and shown to be identical to those of flavin reductases . This strongly suggests that, in general, the reduction of iron depends on reduced flavins provided by flavin reductases.

Appl Environ Microbiol, 1994 Jan, 60(1), 374 - 6
Use of solid-phase PCR for enhanced detection of airborne microorganisms; Alvarez AJ et al.; The solid-phase PCR (SP-PCR) was compared with a culture-based technique for the detection of aerosolized Escherichia coli DH1 . Results with SP-PCR showed an increase in detection sensitivity over that of culture methods . Therefore, SP-PCR may be useful for the detection of airborne microorganisms which may be nonculturable because of aerosolization or sampling stress.

Appl Environ Microbiol, 1994 Jan, 60(1), 313 - 22
Anaerobic degradation of toluene and o-xylene by a methanogenic consortium; Edwards EA et al.; Toluene and o-xylene were completely mineralized to stoichiometric amounts of carbon dioxide, methane, and biomass by aquifer-derived microorganisms under strictly anaerobic conditions . The source of the inoculum was creosote-contaminated sediment from Pensacola, Fla . The adaptation periods before the onset of degradation were long (100 to 120 days for toluene degradation and 200 to 255 days for o-xylene) . Successive transfers of the toluene- and o-xylene-degrading cultures remained active . Cell density in the cultures progressively increased over 2 to 3 years to stabilize at approximately 10(9) cells per ml . Degradation of toluene and o-xylene in stable mixed methanogenic cultures followed Monod kinetics, with inhibition noted at substrate concentrations above about 700 microM for o-xylene and 1,800 microM for toluene . The cultures degraded toluene or o-xylene but did not degrade m-xylene, p-xylene, benzene, ethylbenzene, or naphthalene . The degradative activity was retained after pasteurization or after starvation for 1 year . Degradation of toluene and o-xylene was inhibited by the alternate electron acceptors oxygen, nitrate, and sulfate . Degradation was also inhibited by the addition of preferred substrates such as acetate, H2, propionate, methanol, acetone, glucose, amino acids, fatty acids, peptone, and yeast extract . These data suggest that the presence of natural organic substrates or contaminants may inhibit anaerobic degradation of pollutants such as toluene and o-xylene at contaminated sites.

Am J Ind Med, 1994 Jan, 25(1), 79 - 80
Viral infection enhances lung response to Micropolyspora faeni; Cormier Y et al.; Farmer's lung is an important form of hypersensitivity pneumonitis . It is believed to represent a delayed type allergic reaction to microorganisms found in moldy hay dust . The disease is prevalent in farmers from countries where, because of high humidity in the summer, molding of stored hay is unavoidable.

Am J Ind Med, 1994 Jan, 25(1), 43 - 6
Bacteria, fungi, and endotoxin as potential agents of occupational hazard in a potato processing plant; Dutkiewicz J; Workers in a potato processing plant were exposed at the particular workplace to large concentrations of airborne microorganisms and endotoxin . The presence of precipitins to microbial antigens was significantly correlated with the occurrence of the work-related respiratory and general symptoms that were found in 45.9% of the examined workers.

Am J Ind Med, 1994 Jan, 25(1), 121 - 2
Endotoxin and microorganisms in percolate derived from compostable household waste; Nielsen BH et al.; Health related problems among Danish garbage collectors have been reported . Separated compostable household waste was analyzed for endotoxin and microorganisms in an experimental study . Aerosols and liquid (percolate) from the waste were sampled over two 14-day periods during storage in containers.

Am J Ind Med, 1994 Jan, 25(1), 109 - 12
Experimental grain dust atmospheres generated by wet and dry aerosolization techniques; Thorne PS; Properties of grain dust aerosols generated using wet and dry techniques were studied . Relative to the dry aerosol generation, the wet generation technique yielded a smaller particle size distribution (MMAED of 1.5 microns vs . 15.5 microns) but also reduced the viability of microorganisms . Analysis of dust mass and endotoxin activity on cascade impactor stages demonstrated equivalent partitioning of the airborne endotoxin with the dust mass for aerosols produced by either generation method . Comparison of laboratory-generated atmospheres to field sampling indicated a greater proportion of respirable microorganisms in soybean handling facilities than were generated using the dry aerosol system . Limitations of both aerosol generation systems were found that may affect the validity of inhalation toxicology studies in which these bioaerosols are artificially created.

J Periodontal Res, 1994 Jan, 29(1), 9 - 16
Infection by Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, and antibody responses at different ages in humans; Nakagawa S et al.; This study examined the serum IgG and IgM responses against Porphyromonas gingivalis and 3 serotypes of Actinobacillus actinomycetemcomitans, and the correlations of these responses with age and homologous infection . A total of 90 individuals were included in this study: 40 subjects with gingivitis, 40 periodontally healthy subjects, and 10 adult periodontitis subjects . The subjects in the gingivitis and periodontally healthy groups were divided into 4 stages based on their physiological age: early childhood, school age, puberty, and adult . In the gingivitis group, there was a positive correlation between increase in age and increase in serum IgG antibody levels against P . gingivalis until puberty . However, no statistically significant difference was found between the puberty stage and the adult stage . The average level of IgG antibodies against A . actinomycetemcomitans in the school age gingivitis group was significantly higher than that in the early childhood gingivitis group for all serotypes (p < 0.01) . In serotype c, IgG antibody levels in the school age gingivitis group were significantly higher than in the early childhood gingivitis group or the adult gingivitis group (p < 0.01) . With both P . gingivalis and A . actinomycetemcomitans, positive correlations between elevated IgG level and infections by these microorganisms were found in the puberty gingivitis and adult periodontitis groups.

Crit Rev Microbiol, 1994, 20(2), 95 - 105
Pseudomonas lipases: molecular genetics and potential industrial applications; Soberon-Chavez G et al.; Lipases are esterases able to hydrolyze water-insoluble esters such as long-chain triglycerides . These enzymes also catalyze the formation of esters (esterification) and the exchange of ester bonds (transesterification) when present in nonaqueous media . Lipases display a high degree of specificity and enantioselectivity for esterification and transesterification reactions, and thus their potential uses in industry are very wide . These potential industrial applications have been an important driving force for lipase research during the last several years, and in particular for the study of lipases produced by microorganisms . Pseudomonas lipases are very interesting because they display special biochemical characteristics not common among the lipases produced by other microorganisms, such as their thermoresistance and activity at alkaline pHs . Recently, several Pseudomonas genes have been cloned and sequenced, and the regulation of their expression is beginning to be understood . The molecular genetic approach to the study of Pseudomonas lipases will permit the construction of recombinant strains with increased lipase productivity and will provide the opportunity to modify these enzymes to suit particular industrial applications.

Crit Rev Microbiol, 1994, 20(2), 79 - 85
Microorganisms in the development of subunit vaccines against parasites; Willetts N; Because of the increasing problems of resistance to chemicals and chemical residues, preventative vaccination has increasing appeal as a way to control parasite infestations in humans and in animals . Such vaccines are now feasible through the application of genetic engineering technology to allow production of parasite protective antigens in microorganisms in commercially viable quantities at an acceptable cost . This concept is illustrated by describing research toward subunit vaccines against human malaria (P . falciparum) and against the tropical cattle tick (B . microplus) . Although the concept is straightforward, difficulties include the identification of a protective antigen, refolding of the initial microbial product to achieve the native conformation, and its formulation to produce a vaccine eliciting an adequate and appropriate immune response.

Rev Assoc Med Bras, 1994 Jan-Mar, 40(1), 50 - 8
{Statins in hypercholesterolemia treatment}; Quintao EC; Statins are microorganism derived drugs that greatly impair the cell synthesis of cholesterol by competitively inhibiting the activity of the enzyme HMG-CoA reductase . Statins, however lower the blood level of cholesterol chiefly by increasing the number of high affinity receptors that recognize plasma LDL and by diminishing the VLDL synthesis rate in the liver . The latter explains the mild triglyceride reducing effect of these drugs . Statins efficiency in lowering the plasma cholesterol concentration is comparable to that of the bile acid binding polymers, but is better than that of the fibrates and nicotinic acid . Statins are better tolerated than the latter two drugs but are less efficient in lowering plasma triglycerides and in increasing the HDL-cholesterol concentrations . Tissue selectivity varies for the different statins but this is a secondary issue when the rarity of side effects is taken into account . Statins should be prescribed considering solely their pharmacologic efficiency and cost . Coronary angiography studies in coronary heart disease patients treated with placebo as compared to statins alone, or combined to other lipid lowering drugs, indicate that coronary artery disease regression can be achieved by pharmacological means.

Biosens Bioelectron, 1994, 9(3), 231 - 42
Harmonic 'signatures' of microorganisms; Blake-Coleman BC et al.; The frequency/amplitude effect of various microorganisms exposed to periodic (time varying) electric fields, when proximate to immersed electrodes, has been studied using a novel analytical instrument . The harmonic distribution, in complex signals caused by cells exposed to harmonic free waveforms and occupying part of the electrode/suspension interface volume, was shown to be almost entirely due to the change in the standing interfacial transfer function by the (dielectrically nonlinear) presence of cells . Thus, the characteristic interfacial non-linearity is viewed as variable, being uniquely modulated by the presence of particular cells in the interfacial region . Little can be attributed to bulk (far field) effects . The tendency for subtle (characteristic) signal distortion to occur as a function of particulate (cell or molecular) occupancy of the near electrode interfacial region under controlled current conditions leads to the method of sample characterisation by harmonic (Fourier) analysis . We report here, as a sequel to our original studies (Hutchings et al., 1993; Hutchings and Blake-Coleman, 1993), preliminary results of the harmonic analysis of microbial suspensions under controlled signal conditions using a three-electrode configuration . These data provide three-dimensional graphical representations producing harmonic 'surfaces' for various microorganisms . Thus, cell type differences are characterised by their 'harmonic signature' . The visual distinction provided by these 'surface' forming three-dimensional plots is striking and gives a convincing impression of the ability to identify and enumerate specific microorganisms by acquisition of cell-modulated electrode interfacial Fourier spectra.

Int J Legal Med, 1994, 106(4), 205 - 8
Sudden unexpected nocturnal deaths among Thai immigrant workers in Singapore . The possible role of toxigenic bacteria; Blackwell CC et al.; Sudden Unexpected Nocturnal Deaths (SUND) occur in young, apparently healthy immigrant workers from Thailand, the Philippines and Bangladesh living among ex-patriot labour forces in countries such as Singapore and Saudi Arabia . Several factors associated with these deaths are similar to those observed for Sudden Infant Death Syndrome (SIDS): sleep related and mainly nocturnal occurrence; no prodromal illnesses other than mild respiratory tract infection; exposure to cigarette smoke; absence of invasive microorganisms at autopsy . The hypotheses proposed to explain these deaths in adults are examined . Based on our studies of the role toxigenic bacteria might play in some cases of SIDS, we suggest a new approach to the investigation of SUND.

Schweiz Arch Tierheilkd, 1994, 136(5), 173 - 85
{Bovine virus diarrhea/mucosal disease: a review}; Weiss M et al.; Infections with the Bovine Viral Diarrhea/Mucosal Disease Virus (BVDV) are widespread and cause a variety of diseases including reproductive disorders, abortion and malformation, pneumoenteritis, thrombocytopenia and mucosal disease . Together with the closely related border disease virus of sheep (BDV) and European Swine fever virus (CSFV), also referred to as Hog Cholera virus, BVDV is now classified in the genus pestivirus of the Flaviviridae family . The BVDV exists in two biotypes, noncytopathic and cytopathic, the latter differing in structural proteins from the noncytopathic biotypes . In virus-free animals infection is transient and mostly subclinical or mild but may also lead to an array of diverse symptoms such as pneumoenteritis (often in combination with other microorganisms) . Infection of the developing fetus early in gestation with a noncytopathic biotype of BVDV may result in persistent infection and birth of apparently healthy calves . Such calves may later in their lives develop Mucosal Disease, a lethal course of infection associated with a mutation to the cytopathic biotype or superinfection with a cytopathic BVDV antigenically similar to the non-cytopathic virus already present in these animals . Diagnosis of infections with BVDV is based on the clinical symptoms and demonstration of virus . Paired serum samples allow the detection of seroconversion in acute infections while persistently infected animals are immunotolerant and generally lack antiviral antibody . Although generally found in their respective host species, pestiviruses of cattle, sheep and pigs are capable of crossing the species barrier into the other species . The existence of pestiviruses in wild ruminants and boars may complicate control strategies that are aimed at removing virus carriers and the control of animal movements.

Int J Health Serv, 1994, 24(2), 311 - 35
Nuclear fallout, low birthweight, and immune deficiency; Gould JM et al.; An investigation of the mortality rates of young adults born in the postwar period of large-scale atmospheric nuclear testing (1945-1965) in the United States and other western industrial nations reveals an increasingly anomalous rise in mortality from its previous secular decline . Beginning in the late 1970s and particularly since 1983, the deterioration in the health of the 25-44 age group is related to in utero exposure to fission products in the milk and diet, associated with an unprecedented rise in underweight births and neonatal mortality known to be accompanied by loss of immune resistance . The 1945-1965 rise in the percentage of live births below 2500 grams is highly correlated with the amount of strontium-90 in human bone, both peaking in the mid-1960s . In the 1980s, for the baby boom generation (those born between 1945 and 1965), cancer incidence and mortality due to infectious diseases associated with a rising degree of immune deficiency, such as pneumonia, septicemia, and AIDS, increased sharply . This process of increasing immune deficiency appears to have been exacerbated by continuing secondary exposures to accidental reactor releases and by an acceleration of radiation-induced mutation of pathogenic microorganisms increasingly resistant to drugs.

Curr Opin Periodontol . 1994;:111-8.
The nonantimicrobial properties of tetracycline for the treatment of periodontal disease; Vernillo AT et al.; Tetracyclines have nonantimicrobial properties that appear to modulate host response . In that regard, tetracyclines and their nonantimicrobial chemically modified analogues (chemically modified tetracycline molecules {CMTs}) inhibit the extracellular activity of mammalian neutrophil and osteoblast collagenases . The activity of this matrix metalloproteinase appears crucial in the destruction of collagen . Apart from its anticollagenase effect, tetracyclines are also potent inhibitors of osteoclast function . Several recent studies have also addressed the therapeutic potential of tetracyclines and CMTs in periodontal disease . These drugs reduced excessive gingival collagenase activity and severity of periodontal breakdown in rats infected with Porphyromonas gingivalis and in diabetic rats . CMT was not associated with the emergence of resistant microorganisms . In human double-blind clinical trials, low-dose doxycycline therapy substantially reduced collagenase activity in the gingival and crevicular fluid, and prevented the loss of attachment in adult periodontitis without the emergence of doxycycline-resistant microorganisms . Tetracyclines and CMTs have enormous therapeutic potential because these drugs can inhibit the activity of matrix metalloproteinases as well as osteoclast function, and thus prevent the degradation of osseous connective tissues in periodontal as well as arthritic diseases.

Wiad Lek, 1994 Jan-Feb, 47(1-2), 22 - 4
{Susceptibility to antibiotics of bacterial strains isolated from the vagina of women in labor}; Blaszczak G et al.; On the basis of vaginal secretion cultures in 520 pregnant women admitted for labour, the susceptibility to drugs was studied of bacteria present in it . Four basic antibiotic groups were taken into account: penicillin derivatives, tetracyclines, aminoglycosides, cephalosporins . A higher resistance to the studied drugs was found of Gram (+) than Gram (-) bacteria, while the highest susceptibility was found to cephalosporins, and the lowest to aminoglycosides . Of interest was the high sensitivity of microorganisms to penicillin derivatives, which is of significant importance in view of their slight side effects and relatively low treatment cost.

Biosens Bioelectron, 1994, 9(2), 131 - 8
The rapid potentiometric detection of catalase positive microorganisms; Cowell DC et al.; The rate of fluoride ion release from the enzymatic cleavage of fluoride ion from 4-fluorophenol by horseradish peroxidase, in the presence of hydrogen peroxide, was measured using a fluoride ion selective electrode . Monitoring the utilisation of hydrogen peroxide by catalase (intracellularly present in almost all aerobic microorganisms) in the presence of 4-fluorophenol demonstrated the inhibition of the enzyme . Horseradish peroxidase appeared to impart a partial protective mechanism of this inhibition . The development of a sequential assay demonstrated the applicability of the proposed method in the assessment of aerobic microorganism numbers . The judicious variation of three parameters, the length of incubation, the concentration of the primary substrate (hydrogen peroxide) and the indicator enzyme activity (horseradish peroxidase), affected both the detection limit and the sensitivity of the assay . Typically with a 15 minute incubation, a detection limit for catalase activity of 1.5 x 10(-6) Uml-1 was obtained together with a sensitivity of 2.42 mumol l-1 s-1 per decade change in activity . Application of the developed catalase assay to the detection of Escherichia coli achieved a detection limit of 1 x 10(2) colony forming units (cfu) ml-1 with a sensitivity of 3.26 mumol l-1 s-1 per decade change in intact microorganisms . By lysis of the microorganisms the detection limit was further reduced to less than 10 cfu ml-1, indicating the future possibilities of the assay.

Biosens Bioelectron, 1994, 9(2), 105 - 9
Using feed-forward neural networks for estimation of microbial concentration in a simulated biochemical process; Bulsari A et al.; This work investigated the feasibility of using feed-forward neural networks for estimation of a state variable in a process with highly non-linear characteristics . A biochemical process was considered where the microorganism Saccharomyces cerevisiae, a yeast, grows in a chemostat on a glucose substrate and produces ethanol as a product of primary energy metabolism . Three state variables for the process are the microbial concentration, substrate concentration and product concentration . The Levenberg-Marquardt Method was used to train the neural networks by minimising the sum of squares of the residuals . The inputs to the networks were the measured variable (product concentration) and the control variable (dilution rate) . The output of the network was an estimate for the microbial concentration . Earlier work had shown that system identification of this biochemical process could be performed quite well using feed-forward neural networks . This work demonstrated that state estimation can also be performed successfully using feed-forward neural networks . Knowledge of the process model is not required . The method is simple, reliable and accurate enough for engineering purposes . It can save a lot of expense on sensors, their installation and maintenance.

Prev Med, 1994 Jan, 23(1), 40 - 7
Characteristics of women nonsmokers exposed to passive smoke; Cress RD et al.; BACKGROUND . Studies that have investigated the association between exposure to passive smoke and increased risk for disease have had inconclusive results and have raised questions about whether women exposed to passive smoke differ from those not exposed . METHODS . The study population included 120 women nonsmokers who reported that they had been exposed to passive smoke in the 24 hr prior to the interview and 213 women who reported no exposure . Women were queried about demographic, lifestyle, sexual, and reproductive factors . RESULTS . Exposed women were younger, less educated, and slightly heavier than nonexposed women . They were more likely to be divorced or separated (OR = 3.3, 95% CI = 1.4-7.6, P = 0.005), to have had first intercourse at or before age 16 (OR = 1.4, 95% CI = 1.0-1.9, P = 0.04), and to have had three or more live births (OR = 2.9, 95% CI = 1.2-6.8, P = 0.02) . Women exposed to passive smoke were more likely to have consumed two or more cups of coffee (OR = 2.0, 95% CI = 1.1-3.8, P = 0.03), two or more glasses of beer (OR = 3.7, 95% CI = 1.1-12.5, P = 0.03), or to have smoked marijuana in the past 24 hr (OR = 14.7, 95% CI = 1.8-122.3, P = 0.01) than women who were not exposed . There were no differences noted between exposed and nonexposed women in history of gynecologic diseases or number of cervical microorganisms . CONCLUSION . Women exposed to passive smoke differed from those not exposed on several factors that should be considered in future studies that seek to investigate smoking-related disease risk.

Medicina (B Aires), 1994, 54(2), 97 - 102
{Humoral response to mycobacteria in patients with Crohn disease}; Morgante P et al.; The recent recovery of Mycobacterium paratuberculosis from tissues of patients with Crohn's disease has highlighted the possible etiologic role of this microorganism in the disease . However, the immunological evidence generated by various groups supporting this hypothesis is as yet inconclusive . A specific antibody response might be masked in these patients by the wide antigenic homologies prevailing within the genus Mycobacterium . The present study was undertaken with the purpose of exploring the humoral response to M . paratuberculosis in patients with Crohn's disease, by means of a cross-absorption procedure recently proposed for unveiling the presence of specific antibodies in bovine paratuberculosis . Antibodies IgG to M . paratuberculosis were investigated by enzyme-linked immunosorbent assay in 90 serum samples from 17 patients with Crohn's disease, 23 patients with ulcerative colitis an 14 with other bowel diseases . Samples from 86 subjects without bowel disease (healthy individuals and patients with tuberculosis, mycobacterioses and fungal diseases) were also included as controls . The specificity of these antibodies was explored by the absorption of sera with an ubiquitous Mycobacterium (M . phlei) . The results were compared to those obtained by similar ELISA tests employing M . avium or M . tuberculosis as antigens . A faint humoral response to M . paratuberculosis and M . tuberculosis was detected in patients with Crohn's disease . Cross-absorption with M . phlei did not disclose a specific response nor was an increase in antibody levels detected in patients studied periodically . Sera from patients with ulcerative colitis and other bowel diseases also showed a slight reaction to mycobacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Reprod Nutr Dev, 1994, 34(4), 281 - 8
Effect of extraction method on activities of polysaccharide-depolymerase enzymes in the microbial population from the solid phase in the rumen; Noziere P et al.; Samples of rumen digesta were collected from 2 cows fed with a 100:0 or 40:60 forage/concentrate diet 1 h before and 2 h after feeding . Enzymes from particle-associated microorganisms were extracted by 5 different methods, including physical (freezing, grinding and sonication) or chemical and enzymatic (autolysis in a buffer, lysozyme and CCl4) treatments . Hydrolytic enzyme activities were measured on 3 polysaccharidic substrates: xylan, carboxymethylcellulose and Avicel cellulose . Contamination of enzyme preparations by feed proteins was evaluated . For the 3 substrates, the effect of feeding (sampling time and diet) on enzyme activities was independent of extraction method . Maximal activities were obtained with treatments including lysozyme and CCl4 or grinding in liquid nitrogen . Contamination of enzyme preparations by feed proteins was higher with chemical and enzymatic methods than with physical treatments.

Eur J Pediatr, 1994, 153(7 Suppl 1), S84 - 5
DNA techniques for screening of inborn errors of metabolism; McCabe ER; Molecular genetic techniques are being used increasingly in newborn screening programs . Initial applications involved genotypic confirmation of positive screening tests by DNA microextraction or direct amplification from the dried blood spots . More recently we have shown that RNA can be microextracted from newborn screening specimens, treated with reverse transcriptase and amplified by the polymerase chain reaction . Primary DNA screening is being considered for medium chain acyl-CoA dehydrogenase deficiency in an attempt to identify and treat affected children before their first hypoglycemic episodes . An exciting new development is the application of DNA "fingerprinting" to the microorganisms used in the bacterial inhibition assays for quality control of these critical biological reagents . Thus, molecular genetic approaches will be valuable, not only for confirmatory testing, but also for primary newborn screening for inborn errors of metabolism.

Crit Rev Biotechnol, 1994, 14(3), 251 - 85
Pathway engineering in secondary metabolite-producing actinomycetes; Piepersberg W; Actinomycetes represent the microbial group richest in production of variable secondary metabolites . These mostly bioactive molecules are the end products of complex multistep biosynthetic pathways . Recent progress in the molecular genetics and biochemistry of the biosynthetic capacities of actinomycetes enables first attempts to redesign these pathways in a directed fashion . However, in contrast to several examples of designed biochemical improvement of primary metabolic processes in microorganisms, none of the products or strains derived from pathway engineering in actinomycetes discussed herein have reached pilot or production scale . The main reasons for this slow progress are the complicated pathways themselves, their complex regulation during the actinomycete cell cycle, and their uniqueness, as most pathways and products are specific for a strain rather than for a given species or larger taxonomic group . However, the modular use of a minimum of very similar enzymes and their conversion of similar intermediates to form the building blocks for the production of a maximum of divergent end products gives hope for the future application of these genetic models for the redesign of complex pathways for modified or new natural products . Several strategies that can be followed to reach this aim are discussed, mainly for the variable 6-deoxyhexose metabolism as an ubiquitously applicable example.

Klin Lab Diagn, 1994, (4), 42 - 3
{A chamber for microorganism microcultivation with microscopic monitoring}; Bil'ko IP; A new chamber for microorganism microcultivation with microscopic monitoring has been developed and tried . It is not only fit for microcultivation of various microorganism species but is characterized by a number of advantages over the known chambers as well.

Rev Argent Microbiol, 1994 Jan-Mar, 26(1), 21 - 7
{Isolation and characterization of Azotobacter sp . for the production of poly-beta-hydroxyalkanoates}; Quagliano JC et al.; A microorganism (Azotobacter sp.) was isolated from soil samples from the Agronomy Faculty campus and its ability to accumulate poly-beta-hydroxyalkanoate (PHAs) polymers was analyzed . The isolated strain (named No 8) accumulated 8 micrograms PHA/m of culture media as intracytoplasmic granules . The following properties of the strain were analyzed: utilization of different carbon sources, antibiotic resistance, optimal pH and temperature, pigment production, nitrogen fixation, proteolytic activity, acid and hydrogen sulphide production, optimal growth temperature, cyst formation, growth on phenol and sodium fluoride, catalase, pleomorfism and mobility . The synthesized polymer showed valuable properties respect to organic solvents resistance.

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