Microorganisms

Antimicrob Agents Chemother, 1995 Mar, 39(3), 739 - 45
Antigenic properties and immunoelectron microscopic localization of Mycobacterium fortuitum beta-lactamase; Wagner B et al.; Mycobacterium fortuitum is a fast-growing Mycobacterium species which produces a beta-lactamase involved in the intrinsic resistance of the microorganism to beta-lactam antibiotics . An anti-beta-lactamase serum against the purified enzyme was raised in rabbits . Antibody binding was specific for native beta-lactamase, and enzyme activity was partially inhibited by the serum; furthermore, cross-reactions with denatured class A beta-lactamases were observed . This serum was used as a probe in immunogold labeling for the localization of the cell-bound beta-lactamase in both the low-level producer ATCC 19542 (parental strain) and the overproducer mutant D316 . By the combination of preembedding immunogold labeling and replica technique, it was shown that the beta-lactamase was uniformly distributed on the whole external cell surface, where it appeared to be associated with a Tween 80-removable capsule-like material . Compared with the parental strain, a much higher level of expression of surface enzyme was observed in strain D316 . Surface labeling was more intense in the stationary phase of growth than in exponentially growing cells . The data obtained are interpreted in the context of the intrinsic resistance of M . fortuitum to beta-lactam antibiotics.

Vet Pathol, 1995 Mar, 32(2), 134 - 9
Higher incidence of Gastrospirillum sp . in swine with gastric ulcer of the pars oesophagea; Barbosa AJ et al.; Gastric ulcer in swine is characterized by an area of acid-peptic digestion, occurs usually in the pars oesophagea of the stomach, and has unknown etiopathogenesis . The present work was carried out to investigate the prevalence of the newly described spiral-shaped microorganism Gastrospirillum sp . ("Gastrospirillum suis") in stomachs of abattoir pigs with and without gastric ulcer . Stomachs were removed from 32 consecutive pigs presenting apparently normal mucosa and from 32 additional consecutive pigs presenting frank, chronic gastric ulcer of the pars oesophagea . Fragments of antral, oxyntic, cardiac and pars oesophagea regions were taken from each stomach and processed for histology and for identification of Gastrospirillum sp . in tissue sections . The microorganisms were identified mainly in the mucous layer and in gastric foveolas of the antral and oxyntic mucosa . Forty pigs (62.5%) were positive for Gastrospirillum sp.; among them, 27 (67.5%) had gastric ulcer, and 13 (32.5%) had no ulcer . Twenty-four pigs (37.5%) were negative for Gastrospirillum sp.; among them, five (20.8%) presented with gastric ulcer, and 19 (79.2%) had no ulcer . There was a significant difference between pigs with and without gastric ulcer in regard to the presence of Gastrospirillum sp . (P < 0.01) . The spiral-shaped microorganism Gastrospirillum sp . that inhabits the stomach of pigs should be considered a possible factor connected with the etiopathogenesis of swine gastric ulcer.

Clin Chest Med, 1995 Mar, 16(1), 29 - 44
Epidemiology of nosocomial pneumonia in intensive care unit patients; George DL; Pneumonia is the most commonly reported nosocomial infection in ICU patients, occurring predominantly in patients whose lungs are ventilated, at a rate of 1% to 3% per day of mechanical ventilation . Substantially increased costs and mortality have been attributed to nosocomial pneumonia . Our understanding of the epidemiology of nosocomial pneumonia in ICU populations has been limited by the reliance of most published studies on clinical diagnostic criteria, which are nonspecific . In addition to mechanical ventilation and tracheal intubation, other suspected risk factors of importance include chronic lung disease, age, severity of illness, upper abdominal or thoracic surgery, head trauma or depressed level of consciousness, and gastric acid inhibition . Aspiration appears to be the primary mode of inoculation of microorganisms into the distal lung; however, the relative importance of different sites as reservoirs for aspiration is controversial . It is hoped that studies based on improved diagnostic techniques, such as quantitative cultures of protected brush or bronchoalveolar lavage specimens, will provide the basis for an improved understanding of the epidemiology and prevention of this important infection in critically ill patients.

Plant Mol Biol, 1995 Mar, 27(5), 995 - 1001
Characterization of two proteinase inhibitor (ATI) cDNAs from alfalfa leaves (Medicago sativa var . Vernema): the expression of ATI genes in response to wounding and soil microorganisms; McGurl B et al.; cDNAs encoding two Bowman-Birk proteinase inhibitors were isolated from the leaves of alfalfa (Medicago sativa) . The cDNAs are derived from a small gene family (3 to 10 genes) encoding alfalfa trypsin inhibitors (ATIs) . Each cDNA clone encoded a mature ATI that was part of a larger, putative preprotein . ATI mRNAs are continuously expressed in flower parts, but are mechanically wound-inducible in the stems and leaves . ATI mRNA is shown to be continuously present in roots of soil-grown plants, but its presence is primarily in response to microorganisms present in the soil . Additionally, while mechanical wounding of the alfalfa roots induced ATI mRNA synthesis both in the roots and in the leaves, microbial infection of the roots triggered ATI mRNA synthesis in the roots but not in the leaves . These results suggest that both local and systemic signalling pathways for proteinase inhibitor synthesis are present in alfalfa plants.

Biosci Biotechnol Biochem, 1995 Mar, 59(3), 487 - 91
Purification and properties of fructosyl lysine oxidase from Fusarium oxysporum S-1F4; Sakai Y et al.; Fructosyl lysine oxidase (FLOD) was examined for its use in the enzymatic measurement of the level of glycated albumin in blood serum . To isolate microorganisms having such an enzyme activity, we used N epsilon-fructosyl N alpha-Z-lysine (epsilon-FL) as a sole nitrogen source in the enrichment culture medium . The isolated fungus, strain S-1F4, showed a high FLOD activity in the cell-free extract and was identified as Fusarium oxysporum . FLOD was purified to an apparent homogeneity on SDS-PAGE . The molecular mass of the subunit was 50 kDa on SDS-PAGE and seemed to exist in a monomeric form . The enzyme had an absorption spectrum characteristic of a flavoprotein and the flavin was found to be covalently bound to the enzyme . The enzyme acted against N epsilon-fructosyl N alpha-Z-lysine and N alpha-fructosyl N epsilon-Z-lysine and showed specificity for fructosyl lysine residues.

In Vitro Cell Dev Biol Anim, 1995 Mar, 31(3), 196 - 206
A polarized human endometrial cell line that binds and transports polymeric IgA; Ball JM et al.; We have demonstrated that a human endometrial cell line, HEC-1, maintains a transepithelial electrical resistance, directionally transports fluids across the cell monolayer, and releases enveloped viruses at distinct plasma membrane domains: influenza virus is released at the apical surfaces and vesicular stomatitis virus (VSV) at the basolateral surfaces . In addition, we have examined the expression of domain-specific endogenous proteins, including the polyimmunoglobulin receptor . Multiple endogenous polypeptides were found to be secreted into the culture medium at basolateral surfaces, whereas no secretion of specific polypeptides was observed from apical cell surfaces . Distinct patterns of endogenous proteins were also observed on apical and basolateral cell surfaces, with a much more complex polypeptide pattern on the basolateral membranes . Using surface biotinylation and immunofluorescence, the polyimmunoglobulin receptor was found to be expressed on the basolateral surface of HEC-1 monolayers . The specific binding of poly-immunoglobulin A (pIgA) was found to occur on the basolateral surface, and was followed by transcytosis to the apical surface and release into the apical medium . The observed characteristics indicate that the endometrium-derived HEC-1 epithelial cell line can be employed as a model for studies of protein transport in polarized epithelial cells of human endometrial tissues, as well as for studies of the interaction of microorganisms with epithelial cells in the genital tract.

Plant J, 1995 Mar, 7(3), 367 - 79
Molecular evolution of plant beta-glucan endohydrolases; Hoj PB et al.; The evolutionary relationships of two classes of plant beta-glucan endohydrolases have been examined by comparison of their substrate specificities, their three-dimensional conformations and the structural features of their corresponding genes . These comparative studies provide compelling evidence that the (1-->3)-beta-glucanases and (1-->3,1-->4)-beta-glucanases from higher plants share a common ancestry and, in all likelihood, that the (1-->3,1-->4)-beta-glucanases diverged from the (1-->3)-beta-glucanases during the appearance of the graminaceous monocotyledons . The evolution of (1-->3,1-->4)-beta-glucanases from (1-->3)-beta-glucanases does not appear to have invoked 'modular' mechanisms of change, such as those caused by exon shuffling or recombination . Instead, the shift in specificity has been acquired through a limited number of point mutations that have resulted in amino acid substitutions along the substrate-binding cleft . This is consistent with current theories that the evolution of new enzymic activity is often achieved through duplication of the gene encoding an existing enzyme which is capable of performing the required chemistry, in this case the hydrolysis of a glycosidic linkage, followed by the mutational alteration and fine-tuning of substrate specificity . The evolution of a new specificity has enabled a dramatic shift in the functional capabilities of the enzymes . (1-->3)-beta-Glucanases that play a major role, inter alia, in the protection of the plant against pathogenic microorganisms through their ability to hydrolyse the (1-->3)-beta-glucans of fungal cell walls, appear to have been recruited to generate (1-->3,1-->4)-beta-glucanases, which quite specifically hydrolyse plant cell wall (1-->3,1-->4)-beta-glucans in the graminaceous monocotyledons during normal wall metabolism . Thus, one class of beta-glucan endohydrolase can degrade beta-glucans in fungal walls, while the other hydrolyses structurally distinct beta-glucans of plant cell walls . Detailed information on the three-dimensional structures of the enzymes and the identification of catalytic amino acids now present opportunities to explore the precise molecular and atomic details of substrate-binding, catalytic mechanisms and the sequence of molecular events that resulted in the evolution of the substrate specificities of the two classes of enzyme.

Clin Infect Dis, 1995 Mar, 20(3), 501 - 6
Infective endocarditis in patients with negative blood cultures: analysis of 88 cases from a one-year nationwide survey in France; Hoen B et al.; Blood cultures were negative in 88 (14%) of 620 cases of infective endocarditis (IE) documented in France during a 1-year nationwide survey . In 15 of these 88 cases, the causative microorganism was identified: seven cases of Q fever endocarditis and two cases of chlamydial endocarditis were diagnosed by serological and/or immunohistologic techniques, and a pathogen was cultured from five surgically removed valves and one arterial septic embolus . Forty-two (48%) of the 88 cases involved patients who had received antibiotics before the first blood sample was taken for culture . Mortality was lower in this group than among patients who had not previously received antibiotics (7% vs . 22%, P = .05) . Comparison of blood culture-negative cases of IE with blood culture-positive cases revealed that the former tended to occur more often on prosthetic valves (32% vs . 22%, P = .16), were more often left-sided (97% vs . 83%, P = .0009), less often included extracardiac symptoms at presentation (52% vs . 63%, P = .06), and were more often surgically treated (53% vs . 34%, P = .001) . Mortality was similar regardless of the results of blood culture (15% vs . 21%, P = .18) . This study showed that more than 10% of all cases of IE in France are still associated with negative blood cultures and confirmed that a search for pathogens such as Coxiella burnetii and Chlamydia species is worthwhile in this situation.

Mutat Res, 1995 Mar, 346(3), 145 - 9
Genotoxic activity in vivo of the naturally occurring glucoside, cycasin, in the Drosophila wing spot test; Kawai K et al.; Cycasin, methylazoxymethanol-beta-glucoside, is a naturally occurring carcinogenic compound . The genotoxicity of cycasin was assayed in the Drosophila wing spot test . Cycasin induced small single and large single spots on feeding at 10 mumol/g medium . The presence of these spots indicates that cycasin is genotoxic in Drosophila melanogaster . Microorganisms which showed beta-glucosidase activity for cleaving cycasin to toxic aglycon were isolated from gut flora of the Drosophila larvae . Consequently, the Drosophila wing spot test would be useful for mutagenicity screening of other naturally occurring glucosides.

J Steroid Biochem Mol Biol, 1995 Mar, 52(3), 271 - 5
The role of cytochrome P450(11 alpha) in detoxification of steroids in the filamentous fungus Rhizopus nigricans; Breskvar K et al.; The evidence was presented that steroid hydroxylating enzyme complex induced by substrate in the filamentous fungus Rhizopus nigricans (R . nigricans) alleviated toxic effect(s) of the steroid on fungal growth . The growth inhibition of fungal mycelium observed in steroid-containing culture(s) became much more obvious when fungal mycelia were grown in the simultaneous presence of inducing steroid and the P450(11 alpha) inhibitor metyrapone . On the other hand, in experiments where we followed the fate of radioactively labelled progesterone added to the mycelial suspension, we noticed that steroid, after being initially accumulated in the microorganism, was, after some time, released from it; the latter phenomenon was not observed if induction of 11 alpha-hydroxylase was prevented by cycloheximide . Results of experiments presented in this communication can be regarded as the first strong indication that the biological role of P450(11 alpha) induction in R . nigricans is in removal of steroids which are toxic for the mycelium.

Minerva Anestesiol, 1995 Mar, 61(3), 77 - 81
{Role of slime in the pathogenesis of pulmonary infections}; Chini G et al.; Microorganisms have proved to produce an amorphous substance that adheres to surfaces of several medical devices like intravenous catheters and endotracheal tubes . We investigated the presence of slime in endotracheal tubes in our Intensive Care Unit (ICU) in 12 patients . We found in this study no correlation between the strain of bacteria on the surface of endotracheal devices and those responsible for pneumonia.

Ann Ital Chir, 1995 Mar-Apr, 66(2), 217 - 22
Clinical significance and management of pancreatic abscess and infected necrosis complicating acute pancreatitis; Bittner R; Secondary pancreatic infections are most serious and life threatening complications of acute necrotizing pancreatitis . The risk of secondary infection is to a large extend related to duration and extension of pancreatic or peripancreatic necrosis . The combination of abdominal CT-scan with guided percutaneous needle aspiration has been demonstrated to be highly reliable on differentiating between sterile and infected pancreatic necrosis . Previous results suggest a major role of enteric pathogens in this disease . Due to the type of microorganisms and the defence capacity of the patient, the pancreatic infection might result in either elimination of the microorganism, unlimited propagation within devitalized tissue (infected necrosis) or they may remain localized (abscess formation) . Though the most fulminant course of acute pancreatitis is found in patients with early infected necrosis . In these cases an operation is usually necessary within 14 days after onset of symptoms . Persistence or new development of typical symptoms two to five weeks after initial improvement should raise the suspicion of abscess . The finding of infection is an absolute indication for surgical intervention . The intention of surgical treatment in combination with antibiotic therapy is to remove devitalized pancreatic and peripancreatic tissue, evacuate all purulent material and provide continuous drainage either by lavage or "open" abdominal treatment . In this article basic procedures of diagnosis and therapy are discussed.

Xenobiotica, 1995 Mar, 25(3), 229 - 37
Age-dependent intestinal hydrolysis of valproate glucuronide in rat; Slattum PW et al.; 1 . Age-dependent differences in the intestinal hydrolysis of the glucuronide conjugate of valproic acid were evaluated in the Fisher-344 rat at 14 and 40 days, and 24 months of age . 2 . Hydrolysis occurred more quickly when incubations were conducted under anaerobic as compared with aerobic conditions . 3 . The rate of hydrolysis of valproate glucuronide was most rapid in the contents of the large intestine (caecum and colon); no difference in rate was noted between age groups during incubations with large intestinal contents . 4 . Hydrolysis in the tissues of the large and small intestines, and the contents of the small intestine, was more rapid in the 14-day-old rat than in the older age groups . Differences in the rates and sites of hydrolysis in the 14-day-old animal may be due to regional differences in the number and types of microorganisms or mammalian beta-glucuronidase present in the gastrointestinal tract . 5 . Differences in intestinal hydrolysis of valproate glucuronide may account in part for age-related changes in enterohepatic recirculation of valproate in young animals; other mechanisms apparently are responsible for altered valproate disposition in senescent animals.

Eur J Clin Microbiol Infect Dis, 1995 Mar, 14(3), 234 - 7
Presence of Helicobacter pylori in the oral cavity, oesophagus, stomach and faeces of patients with gastritis; Namavar F et al.; The presence of Helicobacter pylori in the oral cavity (6 sites), oesophagus, stomach and bowel of 20 dyspeptic patients was investigated . Samples were cultured on three selective media and analyzed by 16S rDNA polymerase chain reaction (PCR) and southern hybridization . Helicobacter pylori DNA was detected by PCR from oral-cavity samples of three (20%) and from faeces samples of only one (7%) of the patients whose stomach biopsies were positive for Helicobacter pylori . When culture was used, the microorganism's rate of recovery from the oral cavity and faeces was 13% and 7%, respectively . One patient had a Helicobacter pylori-like organism in samples collected from the tongue and palate . Both strains were urease, catalase and oxidase positive and grew microaerophilically but were negative on PCR analysis . This demonstrates the possibility of false identification of Helicobacter pylori by use of routine enzyme reactions . Interestingly, specimens collected from the cheeks of three patients were positive for Helicobacter pylori by PCR analysis . This is the first instance of detection of this microorganism in the cheek.

Acta Gastroenterol Belg, 1995 Mar-Apr, 58(2), 193 - 200
Gastric carcinoma: the Helicobacter pylori trail; Deltenre M et al.; Gastric carcinoma is the world's overall second most common cancer . Besides obvious environmental factors, recent epidemiological studies and a better knowledge of Helicobacter Pylori biological properties revealed that the microorganism is involved in the first steps of gastric carcinogenesis as proposed by the Correa model (from normal gastric tissue through superficial gastritis, multifocal atrophic gastritis, intestinal metaplasia and dysplasia to carcinoma) . Significant correlation between the prevalence of H . pylori infection and incidence of gastric carcinoma (mainly the intestinal type) in various geographical areas has been reported . The high prevalence of HP in pre-neoplastic states and in cases of early gastric cancer indicates the infection would precede the development of gastric cancer . HP-related chronic inflammation of gastric mucosa with increased mucosal cell proliferation, deficit in local ascorbic acid concentration, topical ammonia toxicity are putative mechanisms that overexpose a weakened gastric mucosa to environmental carcinogens.

Microb Pathog, 1995 Mar, 18(3), 197 - 209
Molecular investigation of the role of ApxI and ApxII in the virulence of Actinobacillus pleuropneumoniae serotype 5; Reimer D et al.; The extracellular hemolytic toxins (ApxI and ApxII) of Actinobacillus pleuropneumoniae are thought to be important factors in this microorganism's virulence and the pathogenesis of swine pleuropneumonia . Using the polymerase chain reaction, the apxI locus of a non-hemolytic, avirulent mutant of A . pleuropneumoniae serotype 5 (mIT4-H) generated by chemical mutagenesis (Inzana T . J., Todd J., Veit H . P . Microb Pathog 1991; 10: 281-96) was found to contain deletions that affected major parts of the entire apxICABD operon, thus inactivating each gene in the operon . The apxII locus was not affected . Monoclonal antibodies to ApxI and ApxII were used to confirm that ApxI was not synthesized, and that ApxII was synthesized but not secreted from the cell . The apxICABD genes and apxIBD genes were cloned into a broad host range vector to obtain plasmids pJFF800 and pJFF801, respectively . Each recombinant plasmid was electroporated into strain mIT4-H to obtain strain mIT4-H/pJFF800 and strain mIT4-H/pJFF801, respectively . Strain mIT4-H/pJFF800 exported ApxI and ApxII, and produced hemolytic activity comparable to or exceeding that of wild type strain J45 . Strain mIT4-H/pJFF801 exported only ApxII and produced weak hemolytic activity . Strain mIT4-H/pJFF800 was virulent in mice, and had an LD50 of about 2 x 10(6) colony forming units . In contrast, mIT4-H/pJFF801 and mIT4-H were essentially avirulent in mice, and LD50s for these strains could not be calculated . Strain mIT4-H/pJFF800 was virulent in pigs and caused lethal pleuropneumonia, whereas parent strain mIT4-H was avirulent . Strain mIT4-H/pJFF801 was also able to induce pleuropneumonia in pigs, although a higher dose was required to induce lesions similar to those caused by mIT4-H/pJFF800 . Thus, A . pleuropneumoniae strains that produce ApxI and ApxII require ApxI for full virulence and toxic activity in pigs . However, other factors including ApxII contribute to the virulence of A . pleuropneumoniae in pigs.

Rev Sci Tech, 1995 Mar, 14(1), 21 - 39
History of disinfection from early times until the end of the 18th century; Blancou J; The author describes and analyses the methods of disinfection in use until the end of the 18th century, i.e . before the scientific demonstration of the role of pathogenic microorganisms . These methods are classified into three categories: chemical (by derivatives of sulphur, mercury, copper, and also by alkalis and acids), physical (heating, fumigation, filtration, etc.) and biological (burial) . The author concludes that, despite their empiricism, these methods were of great value to those responsible for controlling diseases of animals, as in some cases they were able to eradicate diseases while still ignorant of the causal mechanisms.

Rev Sci Tech, 1995 Mar, 14(1), 177 - 89
Aircraft and ship disinfection; Cancellotti FM; Shipment of animals, animal products and foodstuffs (for human or animal consumption) by sea and air is economically important . However, the possibilities of pathogen transmission represent a genuine danger, even if veterinary controls are performed continuously . Bacteria, viruses, fungi and parasites excreted by animals may contaminate surfaces and are protected by organic matter . Cleaning is an important step in the sanitizing process, and if this is performed well, more than 90% of microorganisms can be removed . Chemical disinfectants must be compatible with cleaning procedures, instruments and materials used previously, and should be without harmful effects on humans or animals . The author outlines the basic procedures and fundamental principles involved.

Microbiologia, 1995 Mar, 11(1), 23 - 32
{Food preservation through combined processes}; Sala Trepat FJ; Food preservation by combined processes is based on the combination of two or more existing preservation methods with the objective of developing milder preservation procedures . Currently two combined processes (CP) deserve a special attention, the preservation of food by high pressures (HP) and the preservation of food with the combined use of heat and ultrasounds under pressure (Mano-Thermo-Sonication) . In the preservation by HP, the food, at room temperature or at very mild temperature, is held during relatively long periods under very high pressures (100-1000 MPa) to inactivate its enzymes and/or microorganisms . This procedure has proved to be effective to inactivate vegetative cells but much less effective to inactivate most enzymes and bacterial spores . Several kinds of food preserved by this method have already been launched into the market . In Mano-Thermo-Sonication (MTS Process) microorganisms and enzymes are inactivated by a combined heat/ultrasounds treatment under pressure . By this method, the lethality of heat treatments at the same temperature is highly increased . Therefore, the intensity of heat treatments can be drastically reduced . Heat resistance of spores is reduced by a factor of 1/10 and that of enzymes and vegetative cells is reduced by a factor of 1/50 approximately . The applicability of this procedure is currently being investigated.

Microbiologia, 1995 Mar, 11(1), 115 - 24
{Biological control in the preservation of pome fruits}; Vinas I; Fresh fruits are susceptible of be attacked by several pathogenic fungi after harvest due to both their high water and nutrients content and their loss of most of the intrinsic resistance that protected them over their development while attached to the plant . Most rot pathogens can be controlled by various methods such as refrigeration, controlled atmospheres and fungicides . Biological control strategies are emerging as promising alternatives to the use of synthetic fungicides . Several factors must be considered for the selection of biocontrol agents to be used against postharvest fruits diseases . Survivability of the antagonist is a major factor to determine its usefulness . Antagonists must survive and be effective after their exposure to both postharvest treatments and storage conditions . Several antagonistic microorganisms have been found that can effectively inhibit postharvest diseases . Just as there is a diversity among microorganisms, there is also a diversity of mechanisms by which they operate . Although in most cases these mechanisms have not been satisfactorily elucidated, they are likely to involve antibiosis, nutrient competition, stimulation of host defense, predation and parasitism . In many cases, probably more than one mechanism operate . The marketing of some of these antagonists may be feasible and they could be an alternative to synthetic pesticides.

J Biol Chem, 1995 Feb 24, 270(8), 3560 - 4
Interaction of the hemolytic lectin CEL-III from the marine invertebrate Cucumaria echinata with the erythrocyte membrane; Hatakeyama T et al.; CEL-III is one of four Ca(2+)-dependent galactose/N-acetylgalactosamine (GalNAc)-binding lectins from the marine invertebrate Cucumaria echinata which exhibits hemolytic activity, especially toward rabbit and human erythrocytes . The hemolytic activity of CEL-III was also Ca(2+)-dependent and was found to be inhibited by galactose or GalNAc-containing carbohydrates, suggesting that the hemolysis was caused by CEL-III binding to specific carbohydrates on the erythrocyte membrane by Ca(2+)-dependent lectin activity, followed by partial destruction of the membrane . The activity of CEL-III was highest at 10 degrees C and decreased markedly with increasing temperature, unlike usual enzymatic reactions . The hemolytic activity of CEL-III increased with increasing pH from neutral to 10, but almost no hemolysis was observed below pH 6.5 . Immunoblotting analysis of proteins from the erythrocyte membrane after treatment with CEL-III indicated that CEL-III aggregates were irreversibly bound to the membrane . When erythrocytes were incubated with CEL-III in the presence of dextran with molecular masses greater than 4 kDa, lysis was impeded considerably, while a concomitant release of ATP was detected from these osmotically protected cells . It was found that CEL-III released carboxyfluorescein from artificial globoside-containing lipid vesicles, and it is suggested that CEL-III is a novel pore-forming protein with the characteristics of a Ca(2+)-dependent lectin, which may act as a toxic protein to foreign microorganisms.

FEMS Microbiol Lett, 1995 Feb 15, 126(2), 203 - 7
Evidence that the novel microorganism 'Z' may belong to a new genus in the family Chlamydiaceae; Kahane S et al.; The purpose of this study was to investigate possible phylogenetic relationships of a new microorganism called 'Z' . The organism was previously shown to be similar to chlamydia in its growth cycle and some of its metabolic requirements, but different in others and in its major outer membrane protein . In this study we report the sequencing of 'Z"s 16S ribosomal DNA and comparison of the sequence with that of other microorganisms, including chlamydia and rickettsiae . While chlamydial species have 95.5% sequence identity among themselves, 'Z' had 83% identity with them, and 73% identity with certain rickettsia-like organisms . Based on the sequence analyses and taking into account physiologic considerations, we believe that 'Z' may belong to a novel genus in the family Chlamydiaceae.

Proc Natl Acad Sci U S A, 1995 Feb 14, 92(4), 939 - 43
cDNA cloning of prophenoloxidase from the freshwater crayfish Pacifastacus leniusculus and its activation; Aspan A et al.; Prophenoloxidase (proPO), an enzyme that is the terminal component of the so-called proPO activating system, a defense and recognition system in crustaceans and insects, has been purified and cloned from a crayfish blood cell cDNA library . The deduced amino acid sequence codes for a polypeptide with a mass of 80,732 Da, which is close to 76 kDa, the apparent mass of the purified enzyme . proPO contains two copper atoms, and two putative copper-binding sites were found in the deduced amino acid sequence . Sequence comparisons show that these putative copper-binding sites are similar to the corresponding sites in arthropod hemocyanins and also, although the sequence similarities are less extensive, similar to tyrosinases from vertebrates and microorganisms . The purified enzyme is a typical tyrosinase because it hydroxylates monophenols and oxidizes o-diphenols but does not oxidize p-diphenols . If a homogeneous preparation of crayfish proPO were incubated with a homogeneous sample of the proPO activating enzyme, a serine proteinase, the cleavage of proPO by this trypsin-like enzyme was found to occur between Arg-176 and Thr-177.

Tidsskr Nor Laegeforen, 1995 Feb 10, 115(4), 476 - 8
{Induced sputum . Indication for examination in Pneumocystis carinii pneumonia?}; von der Lippe E et al.; Induced sputum is a simple, rapid, and non-invasive technique for detection of Pneumocystis carinii in patients with Pneumocystis carinii pneumonia . In this study 31 patients were examined both with induced sputum and bronchoalveolar lavage . P . carinii was found in 24 patients . In 68% of the samples obtained by the induced sputum method the microorganism was found after Giemsa or methenamine silver staining . In 32% the diagnosis was established in the lavage fluid only . Induced sputum is indicated in moderate cases of P . carinii infection . Bronchoalveolar lavage has to be performed in suspected cases where staining of induced sputum is negative and when coinfection with other microbial agents is suspected.

Gen Physiol Biophys, 1995 Feb, 14(1), 67 - 71
A simple method of determination of partition coefficient for biologically active molecules; Sersen F; A simple method is presented for the determination of partition coefficient of an effector between water environment and biological material, based on concentration-dependent effects . The method allows the determination of partition coefficients for biological objects such as algae, bacteria and other microorganisms.

Mol Pharmacol, 1995 Feb, 47(2), 398 - 402
Structure-activity relationships of new heterocycle-containing bisphosphonates as inhibitors of bone resorption and as inhibitors of growth of Dictyostelium discoideum amoebae; Rogers MJ et al.; The mechanisms by which bisphosphonate drugs inhibit osteoclast-mediated bone resorption are unclear . Effects of bisphosphonates on cellular enzymes, metabolic pathways, and osteoclast morphology have previously been described and could culminate in a generalized cytotoxic effect or a decreased capacity of osteoclasts to resorb bone . Recent studies of the structure-activity relationship for the bisphosphonate side chain indicate, however, that at least the newer generations of nitrogen-containing bisphosphonates probably act by binding to a specific target at a site that is complementary in structure to the bisphosphonate side chain . We have previously proposed that such a target for bisphosphonates is also present in amoebae of the cellular slime mold Dictyostelium discoideum, because growth of this microorganism is inhibited by a wide range of bisphosphonates in a manner that closely reflects the antiresorptive potencies of the bisphosphonates in vivo . We have added support for this view by examining the potency towards Dictyostelium of bisphosphonates in which slight changes in the structure of the side chain or conformational restrictions to the side chain have marked effects on antiresorptive potency . The changes in the side chain that affected the in vivo antiresorptive potency of the bisphosphonates consistently affected in a similar manner the potency of the bisphosphonates as inhibitors of the growth of Dictyostelium amoebae . These observations confirm that bisphosphonate drugs have a molecular target that is common to both Dictyostelium amoebae and osteoclasts.

J Bacteriol, 1995 Feb, 177(4), 1017 - 22
Proton pumping and the internal pH of yeast cells, measured with pyranine introduced by electroporation; Pena A et al.; The internal pH of yeast cells was determined by measuring the fluorescence changes of pyranine (8-hydroxy-1,3,6-pyrene-trisulfonic acid), which was introduced into the cells by electroporation . This may be a suitable procedure for the following reasons . (i) Only minor changes in the physiological status of the cells seemed to be produced . (ii) The dye did not seem to leak at a significant rate from the cells . (iii) Different incubation conditions produced large fluorescence changes in the dye, which in general agree with present knowledge of the proton movements of the yeast cell under different conditions . (iv) Pyranine introduced by electroporation seemed to be located in the cytoplasm and to avoid the vacuole, and therefore it probably measured actual cytoplasmic pH . (v) Correction factors to obtain a more precise estimation of the internal pH are not difficult to apply, and the procedure may be useful for other yeasts and microorganisms, as well as for the introduction of other substances into cells . Values for the cytoplasmic pHs of yeast cells that were higher than those reported previously were obtained, probably because this fluorescent indicator did not seem to penetrate into the cell vacuole.

Infect Immun, 1995 Feb, 63(2), 430 - 6
Identification of a new intestinal spirochete with pathogenicity for chickens; Swayne DE et al.; Two intestinal spirochete isolates obtained from chickens with diarrhea were examined by electron microscopy, biochemical tests, rRNA gene restriction pattern analysis, and multilocus enzyme electrophoresis . One isolate (strain 91-1207/C1) was pathogenicity tested in vivo in chickens . The chicken spirochetes were morphologically indistinguishable from Serpulina innocens and Serpulina hyodysenteriae and phenotypically similar to S . innocens . However, the chicken spirochetes could be distinguished from S . innocens, S . hyodysenteriae, and other swine intestinal spirochetes by rRNA gene restriction pattern analysis and multilocus enzyme electrophoresis . In pathogenicity tests in 1-day-old chicks and 14-month-old hens, chicken spirochete 91-1207/C1 produced pale-yellow, watery cecal contents and mild lymphocytic typhlitis . These findings support the conclusion that avian intestinal spirochetes can be pathogenic to commercial poultry and that the microorganisms are different from intestinal spirochetes that infect pigs.

J Ind Microbiol, 1995 Feb, 14(2), 169 - 77
Metal oxidoreduction by microbial cells; Wakatsuki T; For many organisms, some heavy metals in external media are essential at low concentrations but are toxic at high concentrations . Strongly toxic heavy metals are toxic even at low concentrations . Recently, it was proven that changes of valencies of Fe, Cu and Mn were necessary for these metals to be utilized by organisms, especially microorganism . The valencies of Hg and Cr are changed by reducing systems of cells in the process of detoxifying them . Thus, the processes of oxidoreduction of these metals are important for biological systems of metal-autoregulation and metal-mediated regulation . Metal ion-specific reducing enzyme systems function in the cell surface layer of microorganisms . These enzymes require NADH or NADPH as an electron donor and FMN or FAD as an electron carrier component . Electron transport may be operated by transplamsa-membrane redox systems . Metal ion reductases are also found in the cytoplasm . The affinities of metal ions to ligand residues change with the valence of the metal elements and mutual interactions of various metal ions are important for regulation of oxidoreduction states . Microorganisms can utilize essential metal elements and detoxify excess metals by respective reducing enzyme systems and by regulating movement of heavy metal ions.

Cell Biophys, 1995 Feb, 26(1), 45 - 55
The electrokinetic surface of five enteropathogenic Escherichia coli serogroups; Mangia AH et al.; The surface ionogenicity of five enteropathogenic Escherichia coli serogroups (O111:H2, O111:H12, O125:H9, O119:H6, and O26:H11) was investigated by electrokinetical approaches . All of the studied surfaces are negatively charged with their mean values of zeta potential (ZP) varying from -9.0 (O26:H11) to -11.9 mV (O111:H2) . The populational behavior of the all bacteria are similar since very high ZP values varying from -26 to -30 mV were obtained in experiments carried out with the slip plane calculated at 6.83 nm from the cell surface . All the surfaces are extremely acidic, because the isoelectrophoretic points are localized at pH values below 3.0 . Treatment of the microorganisms with neuraminidase did not alter their surface anionogenicity, while treatment with trypsin or phospholipase C reduced their negative charge.

Bioessays, 1995 Feb, 17(2), 109 - 17
Phagocytosis; Brown EJ; Phagocytosis is the process of recognition and engulfment of microorganisms or tissue debris that accumulate during infection, inflammation or wound repair . This ingestion, which is performed most efficiently by migrating, bone marrow-derived cells called 'professional phagocytes', is essential for successful host defense . Ingestion results when an invading microorganism is recognized by specific receptors on the phagocyte surface and requires multiple, successive interactions between the phagocyte and the target . Each of these interactions results in a signal transduction event, which is confined to the membrane and cytoskeleton around the ligated receptor and which is required for successful phagocytosis . Many molecules found at sites of inflammation or infection stimulate phagocytosis, so that efficient ingestion is confined to the site of infection or inflammation, which in turn limits the proinflammatory and tissue-destructive processes that accompany phagocytosis . This review summarizes current understanding of this critical component of host defense and of its regulation.

Clin Infect Dis, 1995 Feb, 20(2), 461 - 6
Notes on the early history of infective endocarditis and the development of an experimental model; Contrepois A; Experimental models of infective endocarditis antedate Garrison and Freedman's work in 1970 . The hypothesis of the role of parasites (microorganisms) microscopically observed in vegetations and cardiac valves of patients with endocarditis was first put forth by Winge in Sweden in 1869 . Winge's work led Klebs and Rosenbach in Germany to establish, between 1878 and 1881, an animal model of experimental endocarditis in which the aortic valves of rabbits were perforated with a metallic probe (loaded with septic material) introduced through the carotid artery . Ten years after Winge's work, Pasteur emphasized the importance of bacteriologic "blood cultures." During the period 1881-1886, Netter and Grancher (Pasteur's associates) introduced a method for drawing aseptic blood samples from patients with clinical endocarditis and performing bacteriologic blood cultures . In Vienna in 1885-1886, Orth, Weichselbaum, and Wyssokowitsch further developed Rosenbach's procedure of inducing experimental endocarditis by injecting material from a bacterial culture into a rabbit's ear vein . The development of an experimental model of endocarditis by investigators in the latter part of the nineteenth century provided anatomopathological and bacteriologic data that in turn led to a better understanding of infective endocarditis.

Clin Infect Dis, 1995 Feb, 20(2), 291 - 5
The practice of infectious diseases in the 1990s: the Canadian experience; Schlech WF 3rd; A survey of the members of the Canadian Infectious Disease Society was carried out to determine the content of an infectious diseases consultative practice in the 1990s . Respondents were asked to identify all new inpatient, outpatient, and telephone consultations during a 1-week period in 1990 . Consultations were categorized by the infectious disease syndrome of the patient and by the microorganism that was identified . Bacterial infections were the most common cause of inpatient consultations, while viral infections were more common in outpatients . Consultations for parasitic infections were primarily for Pneumocystis carinii pneumonia related to infection with the human immunodeficiency virus (HIV) . "Newer" infectious disease syndromes such as chronic fatigue syndrome, toxic shock syndrome, and Lyme disease were all represented in the responses for the 1-week study period . The significant impact of HIV infection on the overall consultative load suggests that there will be a continuing need for newly trained infectious disease consultants into the 21st century.

Infusionsther Transfusionsmed, 1995 Feb, 22(1), 31 - 5
{Detection and side effects of isoantibodies in intravenously administered immunoglobulin preparations}; Strobel E et al.; BACKGROUND: Intravenous immunoglobulins (IvIg) contain not only the declared antibodies against pathogenic microorganisms, but also all the other antibodies of the blood donors, e.g . against erythrocytic antigens . MATERIALS AND METHODS: We tested 14 IvIg from 7 manufacturers (a total of 40 charges) for isoantibodies and irregular antibodies . To improve the reading of our tests we used the gel centrifugation method (ID-Microtyping-System, Fa . Diamed, Bensheim, Germany) . RESULTS: The highest isoantibody titers were (in 8 charges) 1:32 or 1:64 in the Liss-Coombs test . Irregular antibodies were found in 5 IvIg (maximal titer 1:8) . CONCLUSIONS: Isoantibodies in the IvIg can influence blood group serologic tests . With an example of a newborn who had received IvIg we point to the potential danger of misinterpretation of a positive direct antiglobulin test after administration of IvIg . Therefore we recommend to carry out the direct antiglobulin test before administration of IvIg and to examine all eluates after a positive direct Coombs test not only with 0 RBCs but also with A or B RBCs of the AB0 blood group of the patient.

Ceska Gynekol, 1995 Feb, 60(1), 25 - 30
{Cytodiagnosis and premature birth in light of the Bethesda system}; Kobilkova J et al.; 1 . Evaluation of cytological cervico-vaginal smears by the Bethesda system enlisted cytodiagnostics among important laboratory methods which can be used also in risk pregnancies . 2 . Vaginal cytology makes it possible to test at the same time the hormonal situation during pregnancy, which reflects the placental function, and to evaluate also the vaginal biocenosis . 3 . The authors provided evidence that the large number of superficial cells on the cytological smear (more than 10%) is associated with low oestriol and pregnandiol levels which are warning signs of the approaching termination of pregnancy . 4 . By the action of microorganisms on the vaginal epithelium typical morphological changes develop in the cell nucleus and in the cytoplasm . By polychromatic staining also the causal agents of inflammations and infections threatening the mother and foetus are apparent . 5 . The authors assume that cytological examination and evaluation according to the Bethesda system should be included in the complex of antenatal examinations also in women without clinical symptoms of premature delivery or without signs of vaginal infection.

Inflammation, 1995 Feb, 19(1), 101 - 18
Synergistic effects among oxidants, membrane-damaging agents, fatty acids, proteinases, and xenobiotics: killing of epithelial cells and release of arachidonic acid; Ginsburg I et al.; The assumption that cellular injury induced in infectious and in inflammatory sites might be the result of a well-orchestrated, synergistic "cross-talk" among oxidants, membrane-damaging agents, proteinases, and xenobiotics was further investigated in a tissue culture model employing monkey kidney epithelial cells (BGM) labeled either with 51 chromium or {3H}arachidonate . The cells could be killed in a synergistic manner following exposure to combinations among H2O2 and the following membrane-damaging agents: streptolysins S (SLS) and O (SLO), poly-D-lysine, arachidonic acid, eicosapentanoic acid, arachidic acid, lysophosphatidylcholine, lysophosphatidylinositol, lysophosphatidylglycerol, ethanol, and sodium taurocholate . Peroxyl radical (ROO) generated by azobisdiamidinopropane dihydrochloride (AAPH) further enhanced cell killing induced by SLS, SLO, and nitroprusside when combined with H2O2 and trypsin . BGM cells labeled either with chromium or with tritiated arachidonate, which had been treated with increasing concentrations of sodium nitroprusside (a donor of NO) and with subtoxic amounts of SLS and H2O2, were also killed in a synergistic manner and also lost a substantial amounts of their arachidonate label . Both cell killing and the release of membrane lipids were totally inhibited by hemoglobin (an NO scavenger) but not by methylene blue, an antagonist of NO2-BGM cells that had been treated with increasing concentrations of taurocholic acid were killed in a synergistic manner by a mixture of subtoxic amounts of ethanol, H2O2, and crystalline trypsin (quadruple synergism) . Normal human serum possessing IgM complement-dependent cytotoxic antibodies against Ehrlich ascites tumor cells were killed in a dose-dependent fashion . Cell killing was doubled by the addition of H2O2 . Cell killing and the release of membrane lipids by all the mixture of agonists tested were both strongly inhibited by the antioxidants catalase, Mn2+, vitamin A, and by fresh carrot juice . It appears that in order to overcome the antioxidant capacities of the epithelial cells, a variety of membrane-damaging agents had to be present in the reaction mixtures . Taken together, it might be speculated that the killing of mammalian cells in infectious and in inflammatory sites is a synergistic phenomenon that might be inhibited by antagonizing the cross-talk among the various proinflammatory agonists generated by microorganisms by activated phagocytes or by combinations among these agents . Our studies might also open up new approaches to the assessment of the toxicity of xenobiotics and of safe drugs to mammalian cells by employing tissue culture techniques.

Int J Immunopharmacol, 1995 Feb, 17(2), 133 - 39
Low molecular weight immunomodulators produced by microorganisms; Ishizuka M et al.; In order to develop a new class of low molecular weight immunomodulators for the treatment of incurable diseases involving cancer, hematologic diseases and inflammation, we have sought cytokine inducers and inhibitors of cell adhesion to the extracellular matrix among the low molecular compounds produced by microorganisms . Cytogenin, cytoblastin (a monokine inducer), conagenin (a lymphokine inducer) and delaminomycins and IC-101 (inhibitors of cell adhesion to extracellular matrices) have been recently found in our institute . In this report, we describe the principles of screening and structures, and discuss their biological activities.

Eur J Vasc Endovasc Surg, 1995 Feb, 9(2), 143 - 51
Histopathological characteristics of explanted human prosthetic arterial grafts: implications for the prevention and management of graft infection; Olofsson P et al.; OBJECTIVE: to study the histopathological characteristics of prosthetic vascular graft infection . DESIGN: prospective clinical study over 2 years . SETTING: University Hospital . MATERIALS: 36 infected and 29 uninfected (control) chronically implanted vascular prostheses (half aortic) were removed and 352 sections prepared . CHIEF OUTCOME MEASURES: light microscopy (multiple stains), scanning electron microscopy (SEM), and multiple culture techniques to identify characteristics of healing, infection, and microorganisms . MAIN RESULTS: Acute inflammation (AI) (neurophils, granulocytes and necrosis) were seen in 75% of infected grafts, were most prominent in the perigraft tissue and rarely seen on the luminal surface . These were usually well localised, leaving the remainder of a graft well incorporated with no signs of infection . In 25% of clinically infected, culture-positive grafts there was no significant acute inflammation . Chronic inflammation (CI) (macrophages, lymphocytes, monocytes, giant cells) was seen in 70% of both control and infected grafts . In 50% of both groups a significant lymphocytic population was composed exclusively of T-lymphocytes suggesting a true host vs graft response . Unincorporated chronically implanted grafts (> 1 yr) were seen with equal frequency in the two groups although more diffusely unincorporated grafts were infected . Microorganisms were cultured from 23 infected grafts (64%) and were, at microscopy, mostly found outside the graft and nerves on the luminal side . CONCLUSIONS: This data cast doubt on criteria commonly used to distinguish graft infections and host vs . graft reactions from normal graft healing . Acute and chronic inflammation are not predictive of infection.

Environ Health Perspect, 1995 Feb, 103 Suppl 1, 53 - 8
Trace metal mobilization in soil by bacterial polymers; Chen JH et al.; Enhanced transport of trace metal in porous media can occur in the presence of a ligand or "carrier" that has a high affinity for binding the pollutant, is dispersed and mobile in the soil environment, is recalcitrant with respect to microbial degradation, and is acceptable to the public . These aspects of the facilitated transport to trace metals are discussed with respect to a naturally occurring carrier: extracellular polymers of bacterial origin . The literature is reviewed regarding the production and composition of bacterial extracellular polymers, the processes relevant to the facilitated transport of trace metals in soil by bacterial polymers, and potential for transformation of polymers in soils by microbial degradation . Model calculations of contaminant retardation are presented for the case of polymer-mediated transport of cadmium in a sandy aquifer material . The available information suggests that extracellular polymers can bind metal ions and are mobile in the soil environment . Extracellular polymers also appear to be relatively slowly degraded by soil microorganisms . These properties and the supporting model calculations indicate that extracellular polymers of bacterial origin merit consideration as agents that may be applied to contaminated soils to enhance trace metal mobility.

Appl Environ Microbiol, 1995 Feb, 61(2), 407 - 12
Detection of Legionella species in reclaimed water and air with the EnviroAmp Legionella PCR kit and direct fluorescent antibody staining; Palmer CJ et al.; Reclaimed water is an important resource for areas with inadequate water supplies . However, there have been few studies on the variety of microorganisms found in this type of water, since typically reclaimed water is examined only for the presence of coliform bacteria . Many microorganisms, including the legionellae, are known to be more resistant to chlorine than are coliform bacteria . Previously, we detected > 10(3) Legionella cells per ml in primary and secondary sewage effluents and observed no significant reduction in population numbers throughout the treatment process . In this study, we detected Legionella spp . in chlorinated effluent by using an EnviroAmp Legionella PCR kit and direct fluorescent antibody (DFA) staining . However, we were not able to isolate Legionella spp . from either natural or seeded reclaimed water samples . This suggests that the Legionella spp . detected by the PCR and DFA methods may be injured or viable but nonculturable after exposure to the high residual chlorine levels typically found in this type of water source . The numbers of coliform bacteria were low (< 2 cells per 100 ml) in most reclaimed water samples and were not correlated with the presence or absence of Legionella spp . We also collected air samples from above a secondary aeration basin and analyzed them by using the PCR, DFA, and plate culture methods . Legionella spp . were detected in the air obtained from above the secondary basin with all three methods . We concluded that the PCR was superior to the culture and DFA methods for detecting Legionella spp . in environmental water samples.

Singapore Med J, 1995 Feb, 36(1), 107 - 9
Tuberculosis and invasive pulmonary aspergillosis in a young woman with a myelodysplastic syndrome; Kueh YK et al.; A 29-year-old Chinese woman developed pyrexia, multiple skin abscesses and bilateral fine nodular lung infiltrates about 3 months after the commencement of therapy for idiopathic thrombocytopenic purpura (ITP) . Pseudomonas aeroginosa was isolated from the abscesses but multiple blood and sputum cultures, as well as a broncho-alveolar lavage did not yield any microorganisms . The persistence of fever and pulmonary infiltrates warranted an open lung biopsy which provided a definitive diagnosis of tuberculous-aspergillus granulomatous lung disease . Bone marrow re-examination revised the primary haematological disorder to that of a trisomy 8 associated myelodysplastic syndrome.

Pediatr Allergy Immunol, 1995 Feb, 6(1), 20 - 3
Ontogeny of human mannan-binding protein, a lectin of the innate immune system; Thiel S et al.; Mannan-binding protein (MBP) is a member of the collectins . These lectins are composed of polypeptide chains which contains a collagen-like region and a calcium dependent carbohydrate recognition domain (named a C-type CRD) . MBP binds via the CRD to carbohydrate structures on microorganisms . MBP can activate the complement system when bound to carbohydrate . MBP is thus thought to play a role in the defence against microorganisms . The present report describes the ontogeny of MBP . The level of MBP increase during the first 3 months of life, at which time a stable level is reached, comparable to that seen in adults . On average, the level of MBP at term was 37% of the post 3-month level . Measurements on infants born prematurely showed a 3-fold increase in MBP concentration from the time of birth at around 30 weeks from conception to the 10th week of life.

FASEB J, 1995 Feb, 9(2), 200 - 9
Free radicals and phagocytic cells; Rosen GM et al.; Phagocytes mediate their innate immunological response by releasing products that damage invading microorganisms . These products include proteins such as lysozyme, peroxidases, and elastase as well as reactive oxygen species such as superoxide, hydrogen peroxide, hypohalous acid, and hydroxyl radical . Although it is clear that many phagocytic secretory products have direct cytotoxic potential, understanding is limited of how multiple products interact to generate and modulate the cytotoxic response . This review focuses on recent findings that elucidate the biochemical nature of secretory product interaction in the formation of free radicals, particularly the highly reactive hydroxyl radical . The possible role of these reactions in phagocyte microbicidal activity and inflammatory tissue injury is discussed.

Insect Mol Biol, 1995 Feb, 4(1), 23 - 9
Molecular analysis of the endosymbionts of tsetse flies: 16S rDNA locus and over-expression of a chaperonin; Aksoy S; Based on 16S rDNA sequence comparison, intracellular mycetome-associated endosymbionts (P-endosymbionts) of tsetse flies (Diptera: Glossinidae) form a distinct lineage within the gamma-3 subdivision of proteobacteria, related to the free-living bacterium Escherichia coli, midgut S-endosymbionts of various insects including tsetse flies, and to the P-endosymbiont lineage of aphids, Buchnera aphidicola . Gene organization and expression of several loci in intracellular microorganisms have revealed differences from free-living bacteria . This study analyses two of these characteristics in tsetse endosymbionts; the copy number and gene organization of rDNA operations and the nature of the abundant protein(s) synthesized by these microorganisms . Results indicate that Glossina morsitans morsitans S-endosymbionts have multiple (seven) rDNA operons coding for 16S (rrs) followed by 23S (rrl) gene sequences, whereas tsetse P-endosymbionts have a single, similarly organized rDNA operon . In tsetse mycetocytes in vitro, P-endosymbionts synthesize a predominant protein of 60 kDa in size (p60) which by Western blot analysis shows immunological cross-reactivity with the abundant 63 kDa (p63) protein of B . aphidicola . p63 (also referred to as symbionin) has been characterized as a molecular chaperone, structurally and functionally similar to the groEL protein of E . coli . Under in vitro conditions, tsetse S-endosymbionts synthesize high levels of a similarly-sized protein that cross-reacts with p63 chaperonin . Antisera against the tsetse p60 protein also recognizes p63 protein of B . aphidicola, suggesting that the abundant tsetse endosymbiont protein is a chaperonin.

Transplantation, 1995 Jan 27, 59(2), 234 - 40
Abdominal multivisceral transplantation; Todo S et al.; Under FK506-based immunosuppression, 13 abdominal multivisceral transplantations were performed in 6 children and 7 adults . Of the 13 recipients, 7 (53.8%) are alive and well with functioning grafts after 9 to 31 months . Six recipients died: three from PTLD, one from rejection, one from sepsis, and one from respiratory failure . In addition to rejection, postoperative complications occurring in more than isolated cases included PTLD (n = 6), abdominal abscess formation (n = 5), pancreatitis (n = 3), and ampullary dysfunction (n = 2) . In addition, infection by enteric microorganisms was common during the early postoperative period . Currently, all 7 survivors are on an oral diet and have normal liver function . Two recipients (one insulin-dependent) require antidiabetes treatment, in one case following distal pancreatectomy and in the other after two episodes of pancreatic rejection . Thus, abdominal multivisceral transplantation is a difficult but feasible operation that demands complex and prolonged posttransplantation management . It is not yet ready for application and awaits a better strategy of immune modulation.

J Biol Chem, 1995 Jan 20, 270(3), 1308 - 14
Biosynthetic modulation of sialic acid-dependent virus-receptor interactions of two primate polyoma viruses; Keppler OT et al.; Sialic acids are essential components of the cell surface receptors of many microorganisms including viruses . A synthetic, N-substituted D-mannosamine derivative has been shown to act as precursor for structurally altered sialic acid incorporated into glycoconjugates in vivo (Kayser, H., Zeitler, R., Kannicht, C., Grunow, D., Nuck, R., and Reutter, W . (1992) J . Biol . Chem . 267, 16934-16938) . In this study we have analyzed the potential of three different sialic acid precursor analogues to modulate sialic acid-dependent virus receptor function on different cells . We show that treatment with these D-mannosamine derivatives can result in the structural modification of about 50% of total cellular sialic acid content . Treatment interfered drastically and specifically with sialic acid-dependent infection of two distinct primate polyoma viruses . Both inhibition (over 95%) and enhancement (up to 7-fold) of virus binding and infection were observed depending on the N-acyl substitution at the C-5 position of sialic acid . These effects were attributed to the synthesis of metabolically modified, sialylated virus receptors, carrying elongated N-acyl groups, with altered binding affinities for virus particles . Thus, the principle of biosynthetic modification of sialic acid by application of appropriate sialic acid precursors to tissue culture or in vivo offers new means to specifically influence sialic acid-dependent ligand-receptor interactions and could be a potent tool to further clarify the biological functions of sialic acid, in particular its N-acyl side chain.

Nature, 1995 Jan 19, 373(6511), 264 - 8
Penicillin acylase has a single-amino-acid catalytic centre; Duggleby HJ et al.; Penicillin acylase (penicillin amidohydrolase, EC 3.5.1.11) is widely distributed among microorganisms, including bacteria, yeast and filamentous fungi . It is used on an industrial scale for the production of 6-aminopenicillanic acid, the starting material for the synthesis of semi-synthetic penicillins . Its in vivo role remains unclear, however, and the observation that expression of the Escherichia coli enzyme in vivo is regulated by both temperature and phenylacetic acid has prompted speculation that the enzyme could be involved in the assimilation of aromatic compounds as carbon sources in the organism's free-living mode . The mature E . coli enzyme is a periplasmic 80K heterodimer of A and B chains (209 and 566 amino acids, respectively) synthesized as a single cytoplasmic precursor containing a 26-amino-acid signal sequence to direct export to the cytoplasm and a 54-amino-acid spacer between the A and B chains which may influence the final folding of the chains . The N-terminal serine of the B chain reacts with phenylmethylsulphonyl fluoride, which is consistent with a catalytic role for the serine hydroxyl group . Modifying this serine to a cysteine inactivates the enzyme, whereas threonine, arginine or glycine substitution prevents in vivo processing of the enzyme, indicating that this must be an important recognition site for cleavage . Here we report the crystal structure of penicillin acylase at 1.9 A resolution . Our analysis shows that the environment of the catalytically active N-terminal serine of the B chain contains no adjacent histidine equivalent to that found in the serine proteases . The nearest base to the hydroxyl of this serine is its own alpha-amino group, which may act by a new mechanism to endow the enzyme with its catalytic properties.

Dtsch Med Wochenschr, 1995 Jan 5, 120(1-2), 23 - 8
{Disseminated extrapulmonary tuberculosis in idiopathic CD4-lymphocytopenia}; Neukirch B et al.; A previously healthy, now 42-year-old man suddenly fell ill with bouts of septic fever up to 39.5 degrees C, sweats and weight loss without any demonstrable organ involvement . Physical examination on hospitalization 3 weeks after onset of the illness was unremarkable . Blood sedimentation rate at one hour was 123 mm . There was also a moderate increase in gamma-GT and alkaline phosphatase . Routine bacteriological and serological tests failed to discover a causative microorganism . After imaging tests had provided first indication of splenic and hepatic involvement, biopsies of these two organs demonstrated disseminated epithelioid granulomas and Langhans giant cells . Staining and culturing of pelvic crest biopsy tissue showed evidence of Mycobacterium tuberculosis, but there was no evidence of pulmonary involvement . In addition to four-drug tuberculostatic treatment the patient was given glucocorticoids for several weeks to control the fever bouts . Persistent CD4+ T-lymphocytopenia was demonstrated as the cause of the entirely extrapulmonary tuberculosis in this HIV-negative patient . This is an only recently described and so far unexplained syndrome.

Nature, 1995 Jan 5, 373(6509), 72 - 4
Increased male fertility in Tribolium confusum beetles after infection with the intracellular parasite Wolbachia; Wade MJ et al.; The cytoplasmically inherited microorganism Wolbachia pipientis behaves like a sexually selected trait in its host, the flour beetle Tribolium confusum, enhancing male fertility at the expense of female fecundity . Here we show that infected females have fewer offspring than uninfected females but infected males have a large fertility advantage over uninfected males within multiply-inseminated infected or uninfected females . The male fertility effect accelerates the spread of the Wolbachia through the host population and expands the initial opportunity for hitch-hiking of host nuclear genes . Sperm competition in a host, mediated by endosymbionts, has not been previously described.

Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 9 - 13
The chemistry of poisons in amphibian skin; Daly JW; Poisons are common in nature, where they often serve the organism in chemical defense . Such poisons either are produced de novo or are sequestered from dietary sources or symbiotic organisms . Among vertebrates, amphibians are notable for the wide range of noxious agents that are contained in granular skin glands . These compounds include amines, peptides, proteins, steroids, and both water-soluble and lipid-soluble alkaloids . With the exception of the alkaloids, most seem to be produced de novo by the amphibian . The skin of amphibians contains many structural classes of alkaloids previously unknown in nature . These include the batrachotoxins, which have recently been discovered to also occur in skin and feathers of a bird, the histrionicotoxins, the gephyrotoxins, the decahydroquinolines, the pumiliotoxins and homopumiliotoxins, epibatidine, and the samandarines . Some amphibian skin alkaloids are clearly sequestered from the diet, which consists mainly of small arthropods . These include pyrrolizidine and indolizidine alkaloids from ants, tricyclic coccinellines from beetles, and pyrrolizidine oximes, presumably from millipedes . The sources of other alkaloids in amphibian skin, including the batrachotoxins, the decahydroquinolines, the histrionicotoxins, the pumiliotoxins, and epibatidine, are unknown . While it is possible that these are produced de novo or by symbiotic microorganisms, it appears more likely that they are sequestered by the amphibians from as yet unknown dietary sources.

Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 75 - 82
Chemical ecology: a view from the pharmaceutical industry; Caporale LH; Biological diversity reflects an underlying molecular diversity . The molecules found in nature may be regarded as solutions to challenges that have been confronted and overcome during molecular evolution . As our understanding of these solutions deepens, the efficiency with which we can discover and/or design new treatments for human disease grows . Nature assists our drug discovery efforts in a variety of ways . Some compounds synthesized by microorganisms and plants are used directly as drugs . Human genetic variations that predispose to (or protect against) certain diseases may point to important drug targets . Organisms that manipulate molecules within us to their benefit also may help us to recognize key biochemical control points . Drug design efforts are expedited by knowledge of the biochemistry of a target . To supplement this knowledge, we screen compounds from sources selected to maximize molecular diversity . Organisms known to manipulate biochemical pathways of other organisms can be sources of particular interest . By using high throughput assays, pharmaceutical companies can rapidly scan the contents of tens of thousands of extracts of microorganisms, plants, and insects . A screen may be designed to search for compounds that affect the activity of an individual targeted human receptor, enzyme, or ion channel, or the screen might be designed to capture compounds that affect any step in a targeted metabolic or biochemical signaling pathway . While a natural product discovered by such a screen will itself only rarely become a drug (its potency, selectivity, bioavailability, and/or stability may be inadequate), it may suggest a type of structure that would interact with the target, serving as a point of departure for a medicinal chemistry effort--i.e., it may be a "lead." It is still beyond our capability to design, routinely, such lead structures, based simply upon knowledge of the structure of our target . However, if a drug discovery target contains regions of structure homologous to that in other proteins, structures known to interact with those proteins may prove useful as leads for a medicinal chemistry effort . The specificity of a lead for a target may be optimized by directing structural variation to specificity-determining sites and away from those sites required for interaction with conserved features of the targeted protein structure . Strategies that facilitate recognition and exploration of sites at which variation is most likely to generate a novel function increase the efficiency with which useful molecules can be created.

Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 56 - 61
The chemistry of signal transduction; Clardy J; Several disciplines, including chemical ecology, seek to understand the molecular basis of information transfer in biological systems, and general molecular strategies are beginning to emerge . Often these strategies are discovered by a careful analysis of natural products and their biological effects . Cyclosporin A, FK506, and rapamycin are produced by soil microorganisms and are being used or considered as clinical immunosuppressive agents . They interrupt the cytoplasmic portion of T-cell signaling by forming a complex with a binding protein--FKBP12 in the case of FK506 and rapamycin and cyclophilin A (CyPA) in the case of cyclosporin A (CsA) . This complex in turn inhibits a protein target, and the best understood target is calcineurin, which is inhibited by FK506-FKBP12 and CyPA-CsA . Mutational and structural studies help define how FK506-FKBP12 interacts with calcineurin, and the results of these studies are summarized . The existence of strong FK506-FKBP12 binding suggests that FK506 is mimicking some natural ligand for FKBP12 . Synthetic and structural studies to probe this mimicry are also described.

Acta Cient Venez, 1995, 46(2), 135 - 9
{Production of an acid extract of rice straw}; Zamora R et al.; The chemical composition of rice straw was determined by means of standard analytical procedures . The material showed an adequate content of potentially assimilable carbohydrates for the growth of microorganisms . The optimum result of the rice straw treatment corresponds to a particle size of 60 mesh mixed with 5% H2SO4 in a weight: volume relation of 1:10 and submitted to a temperature of 121 degrees C . Under these conditions a rice straw's acid extract was obtained, containing 20 g/lt of total sugars and 15 g/lt of reducing sugars . This content of sugars is enough to support the growth of microorganisms in aerobic conditions.

Drug Metabol Drug Interact, 1995, 12(3-4), 171 - 87
Plant cytochromes P450: an overview; Durst F et al.; Cytochromes P450 from higher plants share many general characteristics with those from animals and microorganisms . There are now 20 known P450 gene families in plants, with the number rapidly increasing . Many of these enzymes catalyze reactions in the secondary metabolic pathways of higher plants . The sheer number of plant species and the variety of these many pathways together result in the diverse enzyme chemistry available from P450s in the plant kingdom . Highlights of recent findings and of the contents of this journal issue are summarized.

Scanning Microsc, 1995, 9(4), 1121 - 6; discussion 1126
Alterations in intestinal transport of oxalate in disease states; Hatch M et al.; Normally, absorption of oxalate from dietary sources can occur in all segments of the intestinal tract . However, alterations in both the magnitude and direction of oxalate fluxes across the intestine can occur in disease states . In enteric hyperoxaluria, enhanced absorption of oxalate by the large intestine is caused by increased permeability of a shunt conductance induced by malabsorbed bile salts and fatty acids . In this condition, the contribution of a paracellular passive flux of oxalate moving along its electrochemical gradient will predominate when intraluminal concentrations of free oxalate are high . In contrast, in chronic renal failure, secretion of oxalate can occur across both small and large intestine thereby facilitating extrarenal elimination with subsequent degradation by mucosal substrate-specific microorganisms . Clearly, in recent studies of oxalate transport, the intestine has emerged with an integral role in mass balance of oxalate in health and disease.

Rev Esp Cardiol, 1995, 48 Suppl 7, 96 - 107
{Infectious complications in patients undergoing a heart transplant}; Bouza E et al.; Infectious complications are, with rejection, the main cause of morbidity and mortality in heart transplantation recipients . Adequate management of these patients requires an adequate knowledge of risk factors, of most common infectious syndromes and of relevant microorganism, as long as of their resistance pattern . Among the first group, we may mention lower respiratory tract infections, mediastinitis and meningitis, and among the microorganisms, Citomegalovirus, Aspergillus and Toxoplasma gondii . The impressive development of diagnostical techniques and of prophylactic and therapeutical possibilities suggest the convenience of a multidisciplinar approach to these complications.

J Health Polit Policy Law, 1995 Winter, 20(4), 1001 - 24
Miasma and "social factors" in disease causality: lessons from the nineteenth century; Tesh SN; Conventional public health wisdom holds that the end of the nineteenth century saw a dramatic change in beliefs about what causes disease, as early convictions about the importance of broad social factors gave way to a concentration on microorganisms . I argue, however, that in both the middle and late nineteenth century nearly everyone, professionals and laypeople alike, saw disease causality in terms of precise, invisible entities, and that prevention policies were as reductionist and narrow as the available technology would allow . My argument is based on a rereading of the primary documents that other scholars have seen as supporting the idea of two distinct public health periods, and on a new interpretation of the revisionist history that questions the idea . I suggest that health policy analysts today are too vague about the meaning of "social factors" and that disease prevention policies might be better if the term was clarified.

Chir Ital, 1995, 47(2), 14 - 24
{The intestine: a central organ in the pathogenesis of septic complications in acute pancreatitis}; Gianotti L et al.; Despite the array of new diagnostic and therapeutic tools, acute pancreatitis remains a critical condition with a high rate of septic morbidity and mortality . To date the main cause of death is still the occurrence of septic complications . In 80% the cases, the microorganisms responsible for infection are of enteric origin and in 30% of the patients with septic shock, no evident focus of infection is recognized . Bacterial translocation is increasingly accepted as the main cause of infection, sepsis and multiple organ failure in these critically ill patients . The mechanisms facilitating the loss of gut barrier function are overgrowth of enteric bacteria and damage to the intestinal mucosa . Pancreatitis-induced immunosuppression may allow the systemic spread of translocated organisms and subsequent severe septic sequelae.

Adv Neuroimmunol, 1995, 5(3), 299 - 309
Morphine stimulates phagocytosis of Mycobacterium tuberculosis by human microglial cells: involvement of a G protein-coupled opiate receptor; Peterson PK et al.; Opiate-induced immunosuppression has been implicated in the pathogenesis of infections caused by a variety of microorganisms, including human immunodeficiency virus (HIV) . Although effects of opiates on lymphocyte function have been studied more extensively, morphine also has been shown to inhibit several functional activities of mononuclear phagocytes (e.g . chemotaxis, respiratory burst activity and phagocytosis) . Opiate addiction has been identified as a risk factor for clinical tuberculosis prior to the HIV epidemic, and macrophages are a key cell in the pathogenesis of Mycobacterium tuberculosis . Thus, the hypothesis was tested in the present study that morphine would suppress phagocytosis of M . tuberculosis by human microglial cells, the resident macrophages of the brain . Contrary to this hypothesis, treatment of human fetal microglial cell cultures with morphine (10(-8) M) was found to stimulate phagocytosis of nonopsonized M . tuberculosis H37Rv . The stimulatory effect of morphine was blocked by naloxone and the mu opiate receptor selective antagonist beta-funaltrexamine . Also, morphine-induced increase in phagocytic activity was markedly inhibited by pertussis toxin and was unaffected by cholera toxin, suggesting the mechanism of morphine's stimulatory effect on microglial cell phagocytosis involves a Gi protein-coupled mu opiate receptor . The results of this in vitro study support the concept that exogenous and endogenous opioids play an immunomodulatory role within the central nervous system through their interaction with G protein-coupled receptors on microglial cells.

Adv Neuroimmunol, 1995, 5(4), 379 - 410
Nitric oxide in the liver: physiopathological roles; Suzuki H et al.; Many of the known roles of arginine (e.g . in immune function, wound healing, and protection against ammonia intoxication) are mediated by a metabolic pathway synthesising nitric oxide (NO) in the liver . Contrary to some of the current views, liver-produced NO may be basically beneficial, as it exerts both protective actions against tissue injury and cytotoxic effects on invading microorganisms, parasites, or tumor cells . An ongoing equilibrium between NO and other NO-reactive compounds (e.g . O2 and non-heme iron-sulphur-containing moieties) appears to be important in this respect, even under critical conditions . Thus, NO may prevent liver tissue harm from oxidant stress . Only when this putative counterbalance is upset by an uncontrolled, prolonged and/or massive production of NO, liver tissue damage may occur leading to hepatic inflammation or even tumor development . Moreover, the currently available data support the working hypothesis that hepatocytes partake not only to immunoregulatory processes, but even to immune defence mechanisms . Thus, the liver constitutes an excellent model for investigations into the crosstalks regulating the production of NO which take place among not only the various networks operating inside a single hepatic cell, but even the individual types of liver cells.

Vestn Khir Im I I Grek, 1995, 154(3), 63 - 4
{The comparative characteristics of the efficacy of medium- and low-frequency ultrasound in treating the suppurative wound}; Iudin VA et al.; The investigation has been conducted to study the influence of middling and low-frequency ultrasound on the culture of standard microorganisms in vitro and in vivo and on the wound process in 26 patients . It has been shown that the middling ultrasound has a priority bactericidal effect upon the microorganisms and the wound infection . It also makes the process of depuration more active.

Adv Exp Med Biol, 1995, 390, 211 - 6
An improved method for in vitro susceptibility testing of Trichomonas vaginalis; Bromke BJ et al.; A protocol is presented for in vitro susceptibility testing of Trichomonas vaginalis . A 100 ml culture of the microorganisms is prepared for inoculation into antibiotic dilutions and controls by centrifugation, washing with 10 mM HEPES (pH 6.2) plus 1.5 x 10(-1) M NaCl, a second centrifugation and a resuspension in the HEPES-saline buffer . Inclusion of the gelling agent carrageenan in the culture medium permits an ease of harvesting the trichomonads and a reproducible initial cell density of 1-4 x 10(4) cells per ml . Following inoculation, tubes with antibiotic dilutions and controls are incubated anaerobically at 35 degrees C for 48 h, which corresponds to late exponential phase . Inclusion of a negative control helps determine Minimum Lethal Concentration (MLC) values.

Skin Pharmacol, 1995, 8(6), 319 - 25
Optimization of topical erythromycin formulations by ion pairing; Matschiner S et al.; Erythromycin (ERY) is used in the topical treatment of acne vulgaris . In order to decrease the amount of microorganisms markedly, the antibiotic must penetrate into the sebaceous follicles . Firstly, the aim of this study was to improve the lipophilicity of ERY by ion pairing . Secondly, a formulation with optimized penetration of the ion pair was developed . Thirdly, the optimized formulation was compared with formulations containing ethanol and with the commercial product Zineryt . The determination of lipophilicity was based on partition coefficients (PC) and on the penetration of ERY into a modified multilayer membrane system (MMS) . It was shown that the penetration of ERY into a lipophilic acceptor system was three times higher when ion pairing between ERY and octadecansulfonate was used in comparison with the penetration of the ERY base alone . The dosage of the antibiotic used can be markedly reduced by optimizing a vehicle for the ion pair.

Rev Environ Contam Toxicol, 1995, 144, 1 - 93
Ecotoxicology of chlorpyrifos; Barron MG et al.; Chlorpyrifos is a broad-spectrum organophosphorothioate insecticide with a principal mechanism of toxicity by inactivation of acetylcholinesterase at nerve junctions . Unlike certain organochlorine pesticides, chlorpyrifos is relatively nonpersistent (Racke 1993), and its principal degradation products are less toxic than the parent chemical . Species sensitivity varies considerably across kingdom and phyla . In general, aquatic and terrestrial microorganisms and plants are tolerant to chlorpyrifos exposure . Aquatic invertebrates, particularly crustaceans and insect larvae, are sensitive to exposure: LC50s are generally less than 1 microgram/L, and no-observed-effect concentrations may be below 0.1 microgram/L in laboratory studies . Fish appear to be less sensitive, with LC50s generally between 1 and 100 micrograms/L and no-observed effect concentrations of approximately 0.5 microgram/L . In general, saltwater and freshwater organisms exhibit similar sensitivity to chlorpyrifos, considering the extreme phylogenetic and species differences in toxicity . Chlorpyrifos effects in aquatic ecosystems are complex because of the diversity of species assemblages and trophic interactions . In general, functional endpoints (e.g., community metabolism) are less sensitive than structural parameters of ecosystems (e.g., loss of sensitive species) . Ecosystem recovery is dependent on the interaction of a variety of factors including treatment timing and application dose, rate of dissipation, species assemblages, trophic structure, and the reproductive capacity and growth rate of susceptible and tolerant populations . Terrestrial species are relatively tolerant of chlorpyrifos exposure, although contact toxicity to sensitive terrestrial invertebrates may occur at concentrations of 0.1 microgram/insect . Amphibians, birds, and mammals show similar sensitivity to orally administered chlorpyrifos, with LD50s ranging from 8 to > 400 mg/kg body weight . Long-term chronic feeding studies in birds and mammals have shown no observed effect concentrations to be greater than 1 mg/kg food . In general, field studies have shown limited or no acute toxicity to amphibians, reptiles, birds, or mammals.

J Enzyme Inhib, 1995, 9(4), 243 - 52
DMI-1, a new DNA methyltransferase inhibitor produced by Streptomyces sp . strain No . 560; Suzuki K et al.; A new inhibitor of DNA methyltransferase named DMI-1 has been discovered in the culture filtrate of Streptomyces sp . strain No . 560 . DMI-1 was purified by extraction with ethyl acetate followed by Diaion HP-20SS and silica gel column chromatography . The structure of DMI-1 was determined to be 8-methylpentadecanoic acid (C16H32O2) . DMI-1 is a novel inhibitor of methyltransferase isolated from microorganisms and is structurally different from sinefungin and A9145C which are structural analogs of S-adenosylmethionine (methyl donor) . DMI-1 was a strong inhibitor of N6-methyladenine-DNA methyltransferase (M . Eco RI, EC 2.1.1.72) in a noncompetitive manner and its inhibition depended on the pH and temperature in the assay media.

Biochimie, 1995, 77(7-8), 651 - 60
Small G proteins and the neutrophil NADPH oxidase; Dagher MC et al.; The NADPH oxidase of phagocytic cells is a multimeric enzyme complex activated during phagocytosis . It catalyzes the production of the superoxide anion, precursor of many toxic oxygen metabolites involved in the defense against microorganisms . The enzyme becomes active after assembly on a membrane bound flavocytochrome b of cytosolic factors p47 phox, p67 phox and p40 phox and of low molecular mass GTP binding proteins . This paper reviews recent results concerning the role of two small G proteins, Rac and Rap 1A in oxidase activation . Native prenylated small G proteins are either in the form of a complex in which the GDP bound G protein is associated with a guanine nucleotide dissociation inhibitor, GDI, or in an active GTP bound form able to trigger the activity of its effector . Rac and Rho share a common GDI . As chemotaxis, under Rho control, and oxidase activation, under Rac control, show mutually exclusive signalling pathways, we propose a model where the GDI would switch from one pathway to the other by sequestering either Rac or Rho.

Wien Med Wochenschr, 1995, 145(17-18), 385 - 9
{Cellular mechanisms of circadian clocks}; Roenneberg T et al.; The mechanisms of the biological clock are today being investigated in single neurons in cell culture or in unicellular and in other microorganisms . The results show that all components of this "endogenous clock" can be found at the cellular level . The cellular circadian program is controlled by a complex system of biochemical reactions, which can contain more than one circadian pacemaker and which comprises several feed-back loops at the input and the output side . This complex temporal program is a prerequisite for specialization and survival within the chrono-ecological niches of the "temporal space" day . It enables organisms on the one hand to adaptively react to environmental changes and thereby reaching transient independence of the external, physical time course; on the other side, it ensures that the endogenous day never runs out of synchrony with the solar day of the environment.

Scand J Infect Dis, 1995, 27(5), 511 - 4
Cyclospora in patients with traveller's diarrhea; Gascon J et al.; Following the description in 1986 of a new enteropathogen called Cyanobacteria-like body (CLB), several outbreaks caused by this microorganism have been described . Since then several research teams have agreed to place CLB in the genus Cyclospora and to establish the epidemiological, pathogenical and clinical features of the illness . This paper describes and assesses those features in 20 travellers diagnosed with CLB and reviews the main literature concerning this enteropathogen . CLB was found in 2.8% of all cases of traveller's diarrhea in our series.

Arch Tierernahr, 1995, 48(3), 245 - 56
{In vitro studies on glycerol transformation by rumen microorganisms}; Bergner H et al.; Rumen fluid from sheep (non adapted to glycerol) was incubated up to six hours under anaerobic conditions with buffer and mineral solution . Wheat starch was added as substrate in an amount of 1g DM per vessel . Glycerol was additionally admitted to rumen fluid in amounts of 5 to 50% of starch . Carrier-free 14C-glycerol (1.3-labelled) or 15N-labelled NH4Cl were added to different incubation vessels . The disappearance rate of glycerol depended from the amount of added glycerol and incubation time . More than 90% of glycerol disappeared in 2 hours (5% addition), 4 hours (10% addition) and 6 hours (15 to 25% addition) respectively . The sum of volatile fatty acids elevated significant with a higher glycerol addition and 6 hours incubation time . The concentration of propionic acid increased also in dependence of the added glycerol amount and the longer incubation time . The proportion of acetic acid to propionic acid changed from high values (3.5 to 4.0, without glycerol) to the lowest value from 2.5 after 6 hours incubation time and 25% glycerol addition . The most radioactivity of added 14C-glycerol was found in propionic acid and only up to 11% in CO2 . 14C-radioactivity was not detected in methane, lactic acid and acetic acid respectively . The 15N-labelling of TCA-precipitable N-fraction was not influenced by glycerol supplementation but the 15N-incorporation in the bacterial nitrogen fraction was lower in the vessels with glycerol.

Crit Rev Neurobiol, 1995, 9(2-3), 137 - 62
Neurovirulence of pseudorabies virus; Card JP et al.; Virulence is defined as the relative capacity of a microorganism to overcome the defense mechanisms of the host organism and thereby cause disease . Virally induced virulence is usually quantitated by measuring the mean time to death or appearance of symptoms following viral inoculation . In this review we make a distinction between general virulence and neurovirulence . We define neurovirulence as the degree of pathogenesis in the nervous system, but intend it to be more encompassing than the simple ability of the virus to grow in the central nervous system (CNS) . This distinction is made possible by recent advances that permit an integrated assessment of the degree of pathology, reactive gliosis, and inflammatory response to infection in the intact organism with specific antisera and molecular probes.

Gynecol Obstet Invest, 1995, 40(2), 97 - 100
Stable engraftment of human female genital mucous membrane xenografts on SCID mice; Kaufmann R et al.; We developed a model in which full-thickness human genital mucous membranes (fallopian tubes, endometrium) were heterotopically xenografted into the skin of severe combined immunodeficient (SCID) mice . The transplanted tissue retained its human phenotype for at least 4 weeks including the glandular epithelium, the lamina propria, and main parts of the grafted vessels . By using an occlusive chamber filled with covering phosphate-buffered saline we created a system that protected the moist human epithelial surface . This system will allow the study of the interaction of test substances, or of invasive, pathogenic microorganisms, with epithelial cells and other cellular components of the human genital mucosa under in vivo conditions.

J Basic Microbiol, 1995, 35(5), 279 - 84
Studies of rifamycin production by Amycolatopsis mediterranei cells immobilized on glass wool; Abu-Shady MR et al.; Cells of Amycolatopsis mediterranei CBS 42575 were immobilized on glass wool for the production of rifamycins B and SV . Glass wool (CORNING type) of 8 microns in diameter has a better entrapment capacity for microbial cells of microorganism than the other types of glass wool used . The most suitable amount of glass wool was 0.8 g/50 ml . The best initial cell concentration used as inoculum was 40 mg cells/50 ml . Repeated batch production of rifamycins by immobilized cells on glass wool was carried out for 6 repeated batches . The results showed that reduction of batch time from 96 h to 48 h does not decrease rifamycin production by immobilized cells.

G E N, 1995 Jan-Mar, 49(1), 23 - 8
Isolation and axenization of two entamoeba histolytica strains; Urdaneta H et al.; We describe the isolation and axenization of two E . histolytica strains, obtained from the stools of two patients with the clinical diagnosis of dysentery . We used Pavlova's medium for initial polixenic culture, and TYI-S-33 (Diamond's) medium for monoxenic and axenic cultures . In order to eliminate the microorganism contaminating the stools the following antibiotics were used: penicillin, streptomycin, ampicillin, chloramphenicol, kanamycin, nistatin, ceftriaxone and amphoterycin B . Both strains grew in similar culture conditions with a yield of 2 x 10(6) microorganism per tube of 15 ml . Both strains belong to pathogenic zymodemes, and virulence was determined by the capacity for producing hepatic abscesses in 100% of the hamsters inoculated intrahepatically.

Int J Clin Lab Res, 1995, 25(3), 128 - 34
Cytokines in the acquired immunodeficiency syndrome and other infectious diseases; Poli G et al.; The pathogenesis of several infectious diseases is frequently related not only to their etiological agents of viral, bacterial, or parasitic nature, but also to the host immune response . Both inflammatory responses and specific immune responses to the invading microorganisms are controlled by complex networks of intercellular signalling molecules, namely cytokines . This rapidly growing family of mediators includes lymphokines, interleukins, and molecules such as tumor necrosis factors and interferons . Patterns of cytokine production from antigen- or allergen-specific T lymphocytic cell clones have been identified, firstly in animal models and subsequently in man, and are commonly referred to as TH0, TH1, and TH2 profiles . The predominance of one of these profiles strongly influences the type of immune response (humoral versus cellular) and, at least in some experimental models, whether the immune response is protective or harmful . This is most convincingly demonstrated in models of parasitic diseases, but has also been hypothesized to be involved in the pathogenesis of human immunodeficiency virus infection and the acquired immunodeficiency syndrome . Earlier studies on human immunodeficiency virus infection revealed that the replicative capacity of this retrovirus, like the herpes viruses, is strongly influenced by the cytokine milieu of infected cells . Transcriptional and post-transcriptional regulation of human immunodeficiency virus expression by human cytokines are examples of the complex interdigitation of viruses with the host immune system.

Annu Rev Microbiol, 1995, 49, 777 - 805
Microbiology to 10,500 meters in the deep sea; Yayanos AA; Microorganisms in the deep sea live at high pressures, low and high temperatures, and in darkness . These parameters and their food supply govern their lives . The study of these creatures gives us an opportunity to see how life processes work at some of the highest temperatures and pressures of the biosphere . Cultured bacterial isolates can grow to over 100 MPa at 2 degrees C and to over 40 MPa at over 100 degrees C . These cultures comprise the foundation for the study of the molecular biology and biotechnology of these isolates . The PTk diagram shows how temperature and pressure affect the growth rate of a bacterium and helps in the search for relationships among bacteria from habitats differing in temperature and pressure.

Annu Rev Microbiol, 1995, 49, 201 - 38
Polyketide synthase gene manipulation: a structure-function approach in engineering novel antibiotics; Hutchinson CR et al.; Polyketides are produced primarily in microorganisms through a specialized metabolism that is a variation of fatty acid biosynthesis . A strong sequence and mechanistic similarity among many of the fatty acid and polyketide synthase enzymes has led to two paradigms for explaining polyketide biochemistry . In one, polyketides are formed by enzyme complexes consisting of four to seven monofunctional proteins in which the beta-carbonyl groups of the intermediates resulting from the condensation of acetate residues are largely not reduced and cyclization of the intermediates typically produces aromatic compounds . The intermediates in the other model are formed by multifunctional enzymes in which each of the initial condensation products is processed through reduction; reduction and dehydration; or reduction, dehydration, and further reduction cycles to produce highly reduced compounds from acetate, propionate, and butyrate residues . Expression of the genes encoding each type of polyketide synthase, or their mutant forms, has provided much information about the underlying biochemistry and, in some cases, resulted in the formation of novel natural products.

Perit Dial Int, 1995, 15(7 Suppl), S41 - 5; discussion S45-6
In vitro studies on the effect of dialysis solutions on peritoneal leukocytes; Jorres A et al.; Within the limitations of the various experimental protocols there appears to be agreement in the literature that unused dialysis fluids, at least when studied in vitro, adversely affect multiple leukocyte functions . The effects of dialysis fluids on leukocytes that have been reported to date include: 1 . Decreased cell viability of PMNs, PM phis, PBMCs, and lymphocytes; 2 . Inhibited phagocytosis and bacterial killing of various microorganisms by PM phis, PMNs, and peripheral blood leukocytes; 3 . Reduced secretion of leukotrienes (LTB4, LTC4) from peritoneal and peripheral blood PMNs and PBMCs; 4 . Reduced secretion of prostaglandins (PGE2, TXB2 and 6-keto-PGF1 alpha) from PM phi; 5 . Decreased production of many cytokines including TNF alpha, IL-8, and IL-6 in PM phis and PBMCs . In addition, several studies targeting the potential mechanisms by which dialysis solutions inhibit leukocyte function identified the initial low pH of the fluids in combination with their lactate content as being of primary relevance, since they may lead to a rapid intracellular acidification of leukocytes . Moreover, some studies indicated the importance of fluid hyperosmolarity and excessive glucose concentrations . These results are indirectly supported by recent in vitro investigations of alternative fluids, which showed improved leukocyte function following exposure to solutions with neutral pH, bicarbonate buffer instead of lactate, or normal osmolarity due to use of an alternative osmotic agent (e.g., glucose polymer) . In conclusion, the evidence obtained during in vitro experimentation suggests that current dialysis fluids are, indeed, not biocompatible . However, whether this also bears physiological relevance in vivo remains to be established in controlled clinical trials comparing conventional fluids to alternative solutions with improved biocompatibility . With regard to the future development of in vitro models for biocompatibility assessment, the following guidelines are suggested: 1 . Cell functional parameters should be studied in more than one cell population; 2 . Depending on which fluid aspect is under investigation, short or even very short exposure times should be used (e.g., < 30 min for pH/buffer studies; < 4 hours for osmolality/osmotic agent studies); 3 . In case the parameter/readout of interest requires longer study periods than indicated above (e.g., studies of cytokine induction or surface receptor expression), preincubation/recovery models should be preferred over coincubation experiments.

Rocz Panstw Zakl Hig, 1995, 46(3), 279 - 92
{Abiotic and biotic transformation of persistent organochlorine compounds in the environment}; Strucinski P et al.; The presence of persistent organochlorine compounds in the environment is defined as being of anthropogenic origin . They are the result of intentional production (pesticides, solvents, dielectric and hydraulic fluids, flame retardants etc.) as well as they are produced as unintentional by-products from many processes (incineration, pulp and paper production, use and production of chlorinated aromatic chemicals and PVC) . Nowadays, they are recognized as one of the major classes of the contaminants in the environment because of their wide distribution and a high capacity to bioaccumulate in organisms--especially in higher levels of the trophic food chain . They have been also claimed to cause adverse effects on organisms and human . In the paper, the main classes of chlorinated hydrocarbons are presented, including pesticides, polychlorinated biphenyls and dioxins . The proposed degradative pathways--abiotic (photolysis, hydrolysis) as well as biotic (biotransformation by microorganisms and higher organisms, including human) are reviewed on the basis of current literature.

Riv Eur Sci Med Farmacol, 1995 Jan-Feb, 17(1), 27 - 33
{Heat shock proteins in diabetes mellitus}; Parlapiano C et al.; The Heat Shock Proteins (HSP) are a special category of proteins synthesized from 2 types of cells, one originating from ordinary organs and the other highly specialized ones from mammals . Their synthesis originates from a reaction of the cells to heat shock and therefore it can be thought of as a defense mechanism activated by the cells to protect themselves from the damage done by heat . HSPs are also qualified as "molecular chaperons" since they are present at the assembling of other proteins and they protect them from any possible anomalous interactions even if they do not take an active part in the final making up of the protein itself . This chaperone role is the base of the hypothesis that HSPs could take part in the processing and presentation of the antigens . Two hypothesis have been formed on the role of HSPs in the immunological process . 1) HSP could be antigens that call for an immediate immunological reaction; 2) HSP could set off a self destructive mechanism brought on by an immunological reaction . From all this it emerges that the immunological reaction to HSP has two angles . One is protective in that it allows the cells to eliminate micro foreign-organisms and the other is harmful due to a badly regulated immunological reaction . In some studies it has been demonstrated that patients with varying autoimmunological disorders as LES and rheumatoid arthritis (AR), have autoantibodies against HSPs . Moreover the HSPs of certain microorganisms induce the formation of autoantibodies in the host and the proliferation of T cells in the synovial fluid in patients with AR.(ABSTRACT TRUNCATED AT 250 WORDS)

Scand J Infect Dis, 1995, 27(3), 289 - 90
Actinobacillus actinomycetemcomitans pneumonia with chest wall and subphrenic abscess; Chen AC et al.; A 14-year-old girl had progressive dyspnea and right lower chest pain for about 1 1/2 months and a weight loss of 3 kg in 2 months . Chest X-ray revealed right pleural effusion and a round infiltration over the right lower chest, initially suspected to be malignant . Image study revealed consolidation in the right middle and lower lobes with abscess-like lesions around the right lower pleura and transdiaphrenic involvement to the subphrenic region . The lesion had also invaded the intercostal muscle . The pleural abscess was obtained by fiberoptic thoracoscopy, and culture of the pus grew typical colonies of Actinobacillus actinomycetemcomitans . After the causative microorganism had been identified, cefoxitin was given for 2 weeks followed by oral amoxicillin (250 mg/6 h) for a total period of 3 months . Follow-up chest X-ray revealed resolution of the lung lesions and the patient recovered gradually without any sequelae.

Semin Thorac Cardiovasc Surg, 1995 Jan, 7(1), 47 - 53
The surgical treatment of patients with prosthetic valve endocarditis; David TE; Prosthetic valve endocarditis is associated with high mortality and morbidity . Although antibiotics alone may sterilize an infected prosthetic valve, adjunctive surgical therapy is often necessary . Depending on the virulence of the offending microorganism, the type of prosthetic valve and the site where it was implanted, the infection spreads into paravalvular structures, producing abscess . Systemic embolization of infected material may cause metastatic abscess . Thus, timing of surgery in these patients is crucial to optimize clinical results . An aggressive approach is justifiable in most patients with prosthetic valve endocarditis . It is believed that radical resection of all infected material and reconstruction of the heart and annuli with fresh autologous or glutaraldehyde-fixed bovine pericardium offer the best chance to eradicate the infection . Prolonged antibiotic therapy is also necessary in these patients . In the author's personal experience with 45 patients with prosthetic valve endocarditis, the infection was limited to the valve in 10 patients and had extended into the surrounding tissues in 35 . The operative mortality rate was 13% . The actuarial survival at 5 years was 61% +/- 5% . These results support the premise that radical resection of all infected materials offers a good chance for curing prosthetic valve endocarditis.

Enferm Infecc Microbiol Clin, 1995 Jan, 13(1), 17 - 22
{Comparison of the automatized BacT/ALERT blood culture incubation and reading system and a conventional system}; Alonso C et al.; BACKGROUND: The aim of the present study was to compare the BacT/ALERT blood culture automatic management and reading system (Organon Teknika) with a conventional, nonautomatic technique (DUO, Bio-Merieux) . METHODS: 1,405 blood cultures were parallel compared . 263 of them were positive; out of these, 148 were considered as indicative of septicaemia, 38 of doubtful clinical significance and 77 as accidental contaminations . RESULTS: No differences were detected between both systems neither in the number of isolates obtained nor in the kind of microorganisms recovered or in the number of false-positive or false-negative readings . The conventional system detected 28% of significant isolates during the first 24 hours, reaching 77% after 48 hours; whereas the BacT/ALERT system had detected 57% of significant isolates after 12 hours, reaching 82% after 24 hours (p < 0.001) . CONCLUSIONS: The results obtained and the automatization of the BacT/ALERT system appoint it as a firm candidate to be included into the Clinical Microbiology laboratory routine.

Int J Gynecol Pathol, 1995 Jan, 14(1), 70 - 4
IUD-associated pelvic actinomycosis: a report of five cases; Muller-Holzner E et al.; Five cases of intrauterine device (IUD)-associated tuboovarian actinomycosis are presented . The patients' ages ranged from 33 to 49 years and their IUD usage from 2 to 12 years . Clinical features of the cases included stenosis of the sigmoid colon in 4 cases, ureteric or bladder obstruction in two cases, and rectal fistula in a further instance . All patients were successfully treated postoperatively with penicillin or ampicillin . An initial diagnosis of ovarian carcinoma was considered in all cases . Although Actinomyces is difficult to differentiate histopathologically from microorganisms and other substances that cause the Splendore-Hoeppli phenomenon, morphological diagnosis permits a quicker and more practical approach than bacterial cultures in the establishment of postoperative antibiotic treatment . Intraoperative frozen-section diagnosis of an acute inflammatory process permits the surgeon to make an immediate decision in order to avoid extensive surgery when ovarian carcinoma is suspected.

Rev Clin Esp, 1995 Jan, 195(1), 8 - 11
{Anticardiolipin antibodies in parenteral drug addicts: relationship with HIV}; Gonzalez Dominguez J et al.; The IgG isotype of anticardiolipin antibodies (aCL) and its possible relationship with the immunodeficiency virus (HIV) were studied in 65 parenteral drug addicts (PDA) . Thirty-seven patients were infected in the present study . Nineteen (51%) fulfilled diagnostic criteria of AIDS . Thirty-two of these 37 HIV-positive patients (86%) were IgG-aCL positive . Fourteen (50%) of the 28 HIV-negative patients were IgG-aCL positive . Our study reveals a lack of correlation between aCL and thrombocytopenia . None of the patients had thromboembolic complications . In AIDS patients no relationship was found between IgG-aCL levels and the presence of Pneumocystis carinii, other infections by opportunist microorganism, and clinical deterioration . Highly increased levels of IgG-aCL (> 80 GPL) were observed in three patients with AIDS and infectious endocarditis . In conclusion, given the non-specificity of aCL en PDA, it is our opinion that its measurement is of little help in daily clinical praxis.

J Forensic Sci, 1995 Jan, 40(1), 45 - 54
Validation and population studies of the loci LDLR, GYPA, HBGG, D7S8, and Gc (PM loci), and HLA-DQ alpha using a multiplex amplification and typing procedure; Budowle B et al.; Studies were performed to evaluate the forensic applicability of multiplex amplification of the loci low density lipoprotein receptor, glycophorin A, hemoglobin G gammaglobin, D7S8, and group-specific component (PM loci) and simultaneous typing of these loci using a reverse dot blot approach where allele specific oligonucleotide probes are immobilized on a nylon membrane strip . These results were obtained by using the AmpliType PM PCR Amplification and Typing Kit . The experiments included: mixed body fluid studies; chemical contaminant effects on the DNA in body fluid samples; the effect of typing DNA from body fluid samples deposited on various substrates; the effect of microorganism contamination on typing DNA derived from blood and semen; the effect of sunlight and storage conditions on DNA typing; determination of the sensitivity of detection of the PM test kit; determination of cross-reactivity of DNA from species other than human; typing DNA derived from various tissues from an individual; and an evaluation of the hybridization temperature of the assay . The data demonstrate that DNA exposed to a variety of environmental insults yields reliable PM typing results . Allele and genotype frequencies for six loci (PM loci and HLA-DQ alpha) were determined in African Americans . Caucasians, southeastern Hispanics, and southwestern Hispanics . All loci meet Hardy-Weinberg expectations and there is little evidence for association of alleles between the loci . The frequency data can be used in forensic analyses and paternity tests to estimate the frequency of a multiple locus DNA profile in various general United States populations.

Chemosphere, 1995 Jan, 30(2), 209 - 13
Easy and inexpensive diffusion tests for detecting the assimilation of aromatic compounds by yeast-like fungi . Part I . Assimilation of dihydroxyphenols; Kocwa-Haluch R; A number of easy and inexpensive diffusion tests have been proposed to find microorganisms that are able to decompose aromatic compounds . These tests made it possible to show the assimilation of catechol, resorcinol and hydroquinone by selected yeast-like fungi . The tests may be used to choose highly active strains from culture collections.

Int J Syst Bacteriol, 1995 Jan, 45(1), 188 - 9
Taxonomic note: the potential of dead bacterial specimens for systematic studies; Sneath PH; Consideration should be given to preserving nonliving bacterial specimens as dried material in herbaria for use in future systematic studies . Nucleic acid sequences can be recovered from such material, and it may be possible to utilize it in other techniques . Dried specimens are cheap to prepare and preserve and would record much bacterial variation without the expense of maintaining living cultures . They would also be useful for uncultivable microorganisms . Some technical suggestions are offered.

Ann Chir, 1995, 49(2), 173 - 9
{Rules of decontamination and disinfection of medicosurgical instruments in the operating room}; Dumartin C et al.; Nosocomial infections may result from the reuse of surgical devices if adequate disinfection or sterilization measures are not employed . The first step of reprocessing occurs immediately after use in the operating room . This consists of cleaning and decontamination to eliminate organic material and to reduce the number of microorganisms, in order to protect personnel who subsequently manipulate these instruments and to facilitate the ultimate process of sterilization or disinfection . Instruments that cannot be sterilized must be submitted to "high level disinfection" to remove undesirable microorganisms . In order to guarantee the desired results of disinfection, it is very important to adopt reliable and effective protocols, chemical products with good germicidal properties and with minimal adverse effects on the personnel and the environment . The personnel involved in this delicate and important task must be thoroughly trained . If the above conditions are met, the infectious risk associated with reuse of surgical devices can be controlled.

DNA Res, 1995, 2(1), 21 - 6
cDNA sequences of three kinds of beta-tubulins from rice; Koga-Ban Y et al.; Complete nucleotide sequences of three kinds of rice beta-tubulin cDNA clones (pTUB22, R1623 and R2242) were determined . Southern hybridization indicated that these beta-tubulins consist of one gene family . Using RFLP mapping, these three beta-tubulin cDNAs were mapped to different chromosomes indicating at least three loci for the beta-tubulin gene . The deduced amino acid sequences of these cDNAs showed a high similarity to other plant beta-tubulins . The asparagine residue located at the 100th amino acid from the N-terminus of plant beta-tubulins was also conserved with these three beta-tubulins . This asparagine is thought to be responsible for the sensitivity against rhizoxin, the toxin of the pathogen of rice seedling blight, Rhizopus sp . a soil-borne microorganism . Expression of the three beta-tubulin genes was analyzed by Northern blotting and all three clones were expressed in root, the possible target tissue of rhizoxin . These results suggest that these clones are candidates of beta-tubulins targeted by rhizoxin.

Biotechnol Prog, 1995 Jan-Feb, 11(1), 71 - 9
A kinetic model for substrate and energy consumption of microbial growth under substrate-sufficient conditions; Zeng AP et al.; The growth of heterotrophic microorganisms can be classified into substrate-limited and substrate-sufficient growth according to the relative availability of the substrate (carbon and energy source) and other nutrients . It is generally observed that the consumption rates of substrate and energy (ATP) are higher under substrate-sufficient conditions than under conditions of substrate limitation . The excess substrate and ATP consumption is often influenced by the residual concentration of substrate in a relatively wide range . To account for these effects, a kinetic model is proposed to describe substrate and ATP consumption rates of microbial growth under substrate-sufficient conditions . According to the model, the specific substrate consumption rate of a substrate-sufficient culture can be expressed as the sum of the substrate rate under substrate-limited conditions at the corresponding specific growth rate and an additional consumption rate due to excess substrate . The same kinetic form also applies to the specific ATP consumption rate and to the specific oxygen consumption rate of an aerobic culture, respectively . The linear equations for substrate and ATP consumption rates of Pirt and of Stouthammer and Bettenhousen can be used for substrate-limited growth . The excess of substrate and ATP consumption rates at carbon surplus can be described in a form similar to that of Michaelis-Menten kinetics . The proposed kinetic model has been verified with experimental data from three continuous cultures representing both anaerobic and aerobic microbial growth on substrates with low and high degrees of reductance . Using this model, the parameters maximum growth yield and maintenance requirement (both in terms of substrate and ATP) of a culture under different growth limitations can be better defined and quantified.(ABSTRACT TRUNCATED AT 250 WORDS)

Bioprocess Technol, 1995, 21, 89 - 137
Design, formulation, and optimization of media; Ertola RJ et al.; The fundamental knowledge available about the microorganism, substrates, and process represent the basis on which a rational approach for the design and formulation of media for microbial processes can be attempted . In this respect, it is necessary to analyze critically the main objective to be optimized (yield, productivity, quality of final product, etc.) . The first step of medium development is concerned with the decision to be taken about the adequate components to be used, followed by the calculation of their concentrations . After medium preparation and experimentation, the application of the most appropriate statistical optimization methodology will make it possible to attain the optimal medium . Medium design and formulation for plant cell processes are still carried out on an empirical basis owing to the lack of fundamental knowledge . However, some general guidelines can be given for growth and production media considering the experimental evidence available about the functions and influence of the medium components for promoting growth and product formation . Adequate manipulation of the carbon, nitrogen, and phosphorus sources and phytohormones and the inclusion of precursors and elicitors in the medium represent the best strategy for improving medium development for plant cell processes . The development of cost-effective medium supplies for mammalian cell culture production of proteins is a key element for a commercially successful process . Medium development is a task that requires experience, time, and resources in its solutions, which may be several . An optimal formulation is elusive because there will always be room for improvement, but through systematic, comprehensive work, practical combinations of nutrients, factors, and feeding schedules can be developed in a reasonable time . A properly developed formulation can bring the burden of the medium below 10% of the total cost of a mammalian cell process.

J Biolumin Chemilumin, 1995 Jan-Feb, 10(1), 41 - 8
The influence of age and sex on phagocyte chemiluminescence; McCafferty AC et al.; The process of ageing is associated with increased susceptibility to infection . Phagocytes form the primary defence mechanism against infecting microorganisms, but the influence of ageing on phagocyte function remains controversial . In this study we have applied a microtitre plate phagocyte chemiluminescence (CL) assay suitable for clinical use to compare phagocyte oxidative metabolism in younger healthy subjects (age 20-60 years) and healthy older (60-70 years) subjects . Polymorphonuclear leukocytes (PMNL) and monocytes were stimulated using phorbol myristate acetate (PMA), serum opsonized zymosan (SOZ), and non-opsonized zymosan (ZYM) in the presence of both lucigenin and luminol . Monocytes showed a higher luminol-enhanced CL response to PMA in males compared with females in the younger age group . No PMNL differences were observed between the sexes . Although no differences were found in relation to age when cells were stimulated with PMA and SOZ, significantly lower background (unstimulated) CL was obtained from PMNL with luminol . PMNL luminol-enhanced CL responses were also lower in response to ZYM . The findings suggest a reduced response of PMNL from older subjects to minimal stimulation . This could be related to abnormalities in the triggering of the respiratory burst or myeloperoxidase release due to ageing . The influence of age and sex should be taken into account in clinical studies of phagocyte CL.

C R Acad Sci III, 1995 Jan, 318(1), 135 - 9
Population genetics and strain typing of microorganisms: how to detect departures from panmixia without individualizing alleles and loci; Tibayrenc M; The actual impact of genetic exchange in natural populations of microorganisms is presently under debate . It is indispensable to precisely estimate this parameter in order to assess the stability in space and time of these microorganisms' genotypes, and hence, their epidemiological and medical relevance . Population genetic concepts make it possible to address this question rigorously . Nevertheless, the analyses are made difficult by the fact that very often, the genetic markers used do not allow discrimination of individual alleles and loci . This work presents some linkage disequilibrium tests usable even under these conditions, and hence applicable with any class of marker (isoenzymes, RFLP, RAPD, DNA fingerprinting).

Glia, 1995 Jan, 13(1), 45 - 50
Cytokine modulation of murine microglial cell superoxide production; Hu S et al.; Activated microglia may contribute to two opposite effects during inflammation within the central nervous system: host defense against microorganisms and neuronal injury . Each of these processes may be mediated by the generation of reactive oxygen intermediates by activated microglia . We investigated the effects of two proinflammatory cytokines, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha, and of the anti-inflammatory cytokine, transforming growth factor (TGF)-beta, on murine microglial cell superoxide (O2-) production upon stimulation with phorbol myristate acetate (PMA) . Priming of microglia with IFN-gamma or TNF-alpha resulted in a dose-dependent enhancement of O2- release in response to PMA . The priming effects of these two cytokines were additive, suggesting that they acted by independent mechanisms . We also found that IFN-gamma and TNF-alpha stimulated the release of bioactive TGF-beta and that treatment of microglial cell cultures with TGF-beta antagonized the priming effects of IFN-gamma and TNF-alpha on O2- production . The results of this study have implications for understanding the mechanisms by which cytokines and microglia may contribute to host defense as well as to injury of the brain.

Soz Praventivmed, 1995, 40(2), 116 - 23
{Arguments against routine mumps vaccination}; Albonico HU; Routine immunization against mumps was included in the MMR-elimination-programme of Switzerland despite the lack of any public health necessity . Seven years later, the theoretical presumptions of the mumps immunization campaign are challenged by practical experiences: An unnecessary vaccination proves to be of insufficient efficacy, yet associated with an unexpected high complication rate and bears thus the risk of discrediting also other immunizations in the general public . What could be considered a particular immunization failure reveals important inconsistencies of the entire MMR-mass-immunization-campaign . The project remains epidemiologically highly vulnerable and thus hazardous . Because of its constraining effects on the general population, compatibility with basic civil rights can be questioned . The reasons why some 20% of the Swiss population refuse mumps vaccination are little investigated so far . Nevertheless, research can provide important clues for further investigations in this field . As the maturation of the immune system follows learning principles, the question arises whether childhood diseases are not essential for the normal development of immunocompetence . In cancer therapy new attention is drawn to hyperthermia and thus to the healing potential of fever . And finally, there are concerns about the longterm effects of manipulations of the natural balance between man and microorganisms.

J Trauma, 1995 Jan, 38(1), 5 - 7
Peritoneal lavage in the diagnosis of acute surgical abdomen following thermal injury; Mozingo DW et al.; Intraperitoneal sepsis is difficult to diagnose in thermally injured patients . We reviewed the use of diagnostic peritoneal lavage (DPL) in burn patients suspected of having intraperitoneal infection . Seventeen patients were identified in whom celiotomy, autopsy, or complete recovery could be used to validate the lavage results . A lavage was considered positive if there were greater than 500 white blood cells per mm3 or if microorganisms were present on Gram stain . Six patients had a positive DPL and 11 patients had a negative DPL . There were six true positive, no false positive, ten true negative, and one false negative studies resulting in a sensitivity of 0.86, specificity of 1.00, and diagnostic accuracy of 94% . No complications related to the DPL occurred . This procedure is safe and will rapidly and reliably discriminate between patients needing urgent celiotomy and those requiring further investigation to identify a source of sepsis.

Antonie Van Leeuwenhoek, 1995, 67(1), 111 - 23
Microbial response to environmental changes in an Anaerobic Baffled Reactor (ABR); Nachaiyasit S et al.; Two 10 litre Anaerobic Baffled Reactors (ABR), with 8 separate compartments, were used to examine the effect of Hydraulic Retention Time (HRT), effluent recycle and temperature changes on the trophic groups in anaerobic digestion . A synthetic carbohydrate (sucrose)-protein substrate was used, and the reactors run at 20 h HRT, and 35 degrees C . Changing the HRT from 40 to 20 hours doubled the organic loading which caused accumulation of reduced intermediates . The pattern of Volatile Fatty Acids (VFA) at steady state due to an increase in recycle ratios led to the breakage of microbial flocs, and a reduced overall microbial activity . However, the quantity of reduced intermediates was substantially reduced . Decreasing the temperature to 25 degrees C had differing degrees of influence on reactors I & II, but the same pattern of microbial response occurred; that is the slower growing microorganisms were more affected by the temperature drop . It was found that the unique structure of the ABR brings about the partial separation of acidogenesis and methanogenesis.

J Hosp Infect, 1995 Jan, 29(1), 45 - 56
Bacterial and viral removal efficiency, heat and moisture exchange properties of four filtration devices; Vanderbroucke-Grauls CM et al.; Four devices used for filtration of microorganisms and/or for heating and moistening the ventilated air during mechanical ventilation were evaluated . This evaluation included measurement of bacterial and viral removal efficiency, heat and moisture exchange properties, dead space and air flow resistance . The devices included: Pall BB50T and DAR Sterivent (filtration devices); DAR Hygrobac and Gibeck Humid-vent {heat and moisture exchangers (HMEs)} . The two devices which are primarily conceived as filters, had the highest bacterial and viral removal efficiency (titre reduction of 10(5)-10(6) for bacteria and of 10(4)-10(5) for viruses), while removal efficiencies of the HME devices were lower: titre reduction of 10(4) for bacteria and 10(1)-10(3) for viruses . As expected, heat and moisture output of HMEs was better than that of filters . In mechanical ventilation, dead space and air flow resistance are important properties of devices, which might disturb efficient ventilation . There were only minor differences in dead space and air flow resistance . Resistance to airflow in the HMEs was increased by nebulization of medication (mesna) unlike that of the filters.

Biol Pharm Bull, 1995 Jan, 18(1), 126 - 33
Enhancement of LPS triggered TNF-alpha (tumor necrosis factor-alpha) production by (1-->3)-beta-D-glucans in mice; Ohno N et al.; Effects of (1-->3)-beta-D-glucans on tumor necrosis factor-alpha (TNF-alpha) production in mice in vivo were investigated with or without triggering stimulation of lipopolysaccharide (LPS) . Administration of grifolan (GRN) (100-250 micrograms/mouse) obtained from Grifola frondosa, did not elevate the TNF-alpha concentration in serum, but significantly elevated LPS (10 micrograms/mouse)-elicited TNF-alpha production in serum . The priming effect was observed as early as 2 h after administration and remained high for 3 weeks . The priming effect was dependent on the strain of mice, i.e . ICR, BALB/c, and MRL/lpr (15 weeks old) showed high response . In addition, GRN administration increased membrane-bound TNF-alpha assessed by Western blotting and flow cytometry . Comparing the activity using structurally related glucans obtained from other microorganisms, highly branched glucans, SSG isolated from Sclerotinia sclerotiorum IFO 9395 and OL-2 from Omphalia lapidescence significantly increased TNF-alpha production . Small molecular weight GRN derivatives prepared by heat degradation method showed weaker priming effect . These facts suggested that the glucans showed priming effect of TNF-alpha production in vivo and that this effect was related to the degree of branching and molecular weight.

J Periodontal Res, 1995 Jan, 30(1), 1 - 14
Human antibody responses to outer envelope antigens of Porphyromonas gingivalis serotypes; Ebersole JL et al.; Immunological studies examining the homogeneity of the major antigenic components of P . gingivalis have suggested 3 serotypes and have indicated a limited distribution of the serotypes in an individual patient . These studies prompted us to define the immunodominant antigens and distribution of immune responses to P . gingivalis serotypes . Serum IgG antibody levels in periodontitis patients in the present study were most frequently elevated above the normal subjects when tested against P . gingivalis serotype A (i.e., 33277) . Nearly 1/3 of the patients showed significantly elevated antibody to multiple serotypes of the P . gingivalis apparently resulting from cross-reacting antigens . We determined distinctive differences among outer envelope protein and antigen patterns obtained from the three serotypes . Moreover, the results identified considerable similarities in the qualitative and quantitative antigen response patterns among patients to a particular serotype . There was a strong positive correlation between IgG antibody levels (ELISA) and the total level of reactivity determined in the immunoblots, as well as a positive correlation to the proportion of antibody to particular antigens . These findings suggest that responses to these antigens comprised a major portion of the response to the intact microorganism . Additionally, the detection of antibody to particular antigen bands was indicative of early responses to each of the P . gingivalis serotypes . The results of our study indicate that a subpopulation of periodontitis patients develop an extensive serum antibody response often to multiple serotypes of P . gingivalis and may define a patient population with a P . gingivalis disease . Finally, our results indicate a more consistent antigenic composition for P . gingivalis which may enhance the potential for strategies to immunologically interfere with disease caused by this microorganism.

Mikrobiologiia, 1995 Jan-Feb, 64(1), 137 - 9
{Hydrophobic characteristics of the microorganism cell surface}; Iaskovich GA et al.; Hydrophobic properties of the surface of microorganism cells can be featured by parameters that define the equilibrium of cellular adsorption on liquid carbohydrates: constant of sorption equilibrium, a maximal number of adsorbable cells, as well as coefficient of cellular distribution (Kd) between liquid and organic phases that can be determined either with the equation of adsorption isotherm or experimentally . It is shown that the latter technique gives a more informative characteristics of the hydrophobicity levels in the surface of cells than the percentage of of hydrophobicity cited in literature . The results of this study can be used in the screening of microorganism strains and in the solvation of problems of industrial microbiology related to the fixation of cells on differently structured carriers.

Int J Sports Med, 1995 Jan, 16(1), 34 - 7
Changes in several neutrophil functions in basketball players before, during and after the sports season; Benoni G et al.; Neutrophils play an important role in the immune system, forming the "first line of defence" against invading microorganisms and there are few data available concerning neutrophil functions in relation to exercise . We investigated in 7 basketball professional players possible changes before, during and after the sports season, in some haematological parameters and in several aspects of the phagocytic process of neutrophils, such as adhesion, superoxide anion release and bactericidal activity . Training and competitions produced a significant rise in the number of total leukocytes and differential counts, but the values returned to the pre-start levels 3 weeks after the end of the championship . The bactericidal activity and the superoxide anion released were significantly greater during the sports season, while the percentage of cellular adhesion significantly decreased during the championship; after the sports season the values returned to the control levels . As in the literature data concerning neutrophil functions in relation to exercise are non-convergent, it is important in our opinion, to understand whether the alterations induced by exercise can persist after repeated stimuli.

Bioorg Khim, 1995 Jan, 21(1), 3 - 8
{Bioactive compounds from marine actinomycetes}; Mikhailov VV et al.; Studies of the origin of bioactive metabolites of marine actinomycetes are reviewed . Structures and properties of new metabolites from indigenous marine bacteria from Actinomycetales order, such as a benzanthraquinone antibiotic from a strain of the Chainia purpurogena, istamycins, aplasmomycins, altemicidin, new phenazine esters . C13-butanolide, marinone and debromomarinone, palmyromycin, urauchimicins and some others compounds are presented . Prospects of marine biotechnology and microbiology (with considerable emphasis on the development of the basis biology of marine microorganisms in cultures collection) are discussed.

Arch Microbiol, 1995 Jan, 163(1), 1 - 6
Macroscopic phototactic behavior of the purple photosynthetic bacterium Rhodospirillum centenum; Ragatz L et al.; Most photosynthetic microorganisms have the capability of photosensing light quality and intensity . Movement of motile photosynthetic microorganisms to locales that offer optimal physical and chemical conditions for light-dependent growth provides obvious selective advantages . Among phototrophs, many cyanobacteria and algae migrate towards or away from the direction of light, a process termed phototaxis . In contrast, anoxygenic photosynthetic bacteria are believed to respond to changes in light intensity in a manner that is not related to the direction of light, a process that is often described by the term "photophobic" . We recently reported that "swarm colonies" of the purple photosynthetic bacterium Rhodospirillum centenum are capable of macroscopically visible phototactic behavior . In the present study we further characterize the phototactic behavior of R . centenum swarm colonies and provide an action spectrum that delineates regions of the spectrum that elicit positive and negative phototaxis.

Arch Androl, 1995 Jan-Feb, 34(1), 13 - 32
Real-time sperm separation system: a review of Wang tubes and related technologies; Wang FN; This paper discusses real-time sperm separation technology and the use of Wang tubes for isolating high-quality and fertile sperm . Several methods have been developed and used to prepare a better sperm specimen, including the conventional swim-up technique, Percoll discontinuous density gradient, Sephadex gel filtration, centrifugation, migration-sedimentation, albumin column, and Sperm-prep . However, none of these methods has the ability to isolate from the original ejaculum a large number of highly motile, morphologically normal, and normal-chromatin sperm, while retaining in an adequate volume of physiological medium, free of less-motile and nonmotile sperm, and free of microorganisms, cell debris, seminal plasma, leukocytes, and foreign bodies . These methods should be classified as incomplete techniques of sperm separation and are of only limited effectiveness in infertility treatment . They may also cause irreparable damage to the mother or fetus . Real-time sperm separation technology is based on the observations that nonpathological spermatozoa do not transfer organisms, that the motility pattern and swim-up capacity of pathological sperm are limited or disturbed, and that the movement of sperm differs from the passive motion of nonciliated microorganisms and the random active motion of ciliated microorganisms in terms of velocity and direction . Real-time sperm separation technology encompasses the Wang tube system, which has two main functions: to isolate organisms-free, normal-chromatin, morphologically normal, and highly motile spermatozoa that are suitable for use in infertility treatment, and to prevent sex-linked inherited diseases . The results of these evaluations indicate that real-time sperm separation technology is the most effective and precise method of isolating and decontaminating sperm to date.

Int Rev Cytol, 1995, 157, 181 - 276
Signal transduction by the antigen receptors of B and T lymphocytes; Gold MR et al.; B and T lymphocytes of the immune system recognize and destroy invading microorganisms but are tolerant to the cells and tissues of one's own body . The basis for this self/non-self-discrimination is the clonal nature of the B and T cell antigen receptors . Each lymphocyte has antigen receptors with a single unique antigen specificity . Multiple mechanisms ensure that self-reactive lymphocytes are eliminated or silenced whereas lymphocytes directed against foreign antigens are activated only when the appropriate antigen is present . The key element in these processes is the ability of the antigen receptors to transmit signals to the interior of the lymphocyte when they bind the antigen for which they are specific . Whether these signals lead to activation, tolerance, or cell death is dependent on the maturation state of the lymphocytes as well as on signals from other receptors . We review the role of antigen receptor signaling in the development and activation of B and T lymphocytes and also describe the biochemical signaling mechanisms employed by these receptors . In addition, we discuss how signal transduction pathways activated by the antigen receptors may alter gene expression, regulate the cell cycle, and induce or prevent programmed cell death.

J Clin Microbiol, 1995 Jan, 33(1), 33 - 6
Simple and rapid detection of Mycobacterium tuberculosis complex organisms in bovine tissue samples by PCR; Liebana E et al.; Mycobacterium bovis is a slowly growing microorganism, and confirmation of the diagnosis by conventional culture is a lengthy process . A simple, rapid method for the extraction of DNA from bovine tissue samples was developed and used in a PCR designed for the diagnosis of tuberculosis . Tissues from 81 cattle from tuberculosis-infected herds (group 1) and 19 cattle from tuberculosis-free herds (group 2) were tested in this PCR, and the results were compared with those of conventional culture . The PCR assay detected 71.4% of the culture-positive animals from group 1 . Tissue from all animals in group 2 were negative in the PCR assay and by culture . The described method could be used as a rapid screening technique which would be complementary to culture of tissue specimens for the routine diagnosis of bovine tuberculosis . The PCR technique is much faster than culture and reduces the time for diagnosis from several months to 2 days . It also provides for the detection of M . bovis when rapidly growing Mycobacterium spp . are present in the sample and may be able to detect the presence of M . bovis in samples even when organisms have become nonviable.

Antimicrob Agents Chemother, 1995 Jan, 39(1), 66 - 9
Utilization of time-kill kinetic methodologies for assessing the bactericidal activities of ampicillin and bismuth, alone and in combination, against Helicobacter pylori in stationary and logarithmic growth phases; Coudron PE et al.; Assessment of in vitro susceptibility testing of Helicobacter pylori is difficult because of the fastidious, slowly growing nature of this microorganism . The high rate of relapse observed clinically and a possible subpopulation of cells that are not actively replicating suggest the potential need for bactericidal therapy in order to eradicate H . pylori . We used modified time-kill kinetic methodology in order to evaluate the bactericidal activities of ampicillin and bismuth, alone and in combination, against three strains of H . pylori in both a stationary (slow) growth phase and a logarithmic (rapid) growth phase . We found that ampicillin produced a decrease in CFU per milliliter (2 to 4 log10 units) for three strains of H . pylori when tested in logarithmic growth phases but was less inhibitory (< 1-log10-unit decrease in CFU per milliliter) when tested in a stationary growth phase . In contrast, bismuth, when tested in a logarithmic growth phase, produced little inhibitory effect, as the CFU for all strains tested increased above the inoculum . However, when tested in a stationary growth phase, bismuth produced a decrease in CFU per milliliter of < 1 to > 3 log10 units) . The activities of these two agents when combined mimicked the activity of the most active drug alone for that growth phase . We conclude that the clinical use of ampicillin combined with bismuth has been more effective than that of either agent used alone because ampicillin targets replicating cells, whereas bismuth targets cells that are not actively replicating.

Arch Virol, 1995, 140(8), 1515 - 20
Identification and classification of viruses that have not been propagated; Maniloff J; Microorganisms that cannot be grown in the laboratory can now be tentatively identified, by cloning and sequencing particular nucleic acid segments and then carrying out a comparative sequence analysis with an appropriate database . For bacteria, a few universally distributed genes and gene products have enabled comparative sequence analysis to be used for tentative identification and classification of uncultured bacteria . For viruses, there is no universally distributed viral gene or gene product . However, in a few cases, viruses that could not be propagated in the laboratory have been identified and classified . In these cases, either the entire viral genome sequence was determined or partial sequence information was supplemented with additional data . The Executive Committee of the International Committee on Taxonomy of Viruses (ICTV) has reviewed the issue of identification and classification of viruses that have not been propagated . Under the ICTV system, formal review of any taxonomic proposal is carried out by the relevant ICTV Subcommittee or Study Group . The few examples of unpropagated viruses that have arisen thus far have been readily accommodated within existing viral taxonomy, with the international group of experts comprising each Subcommittee and Study Group determining the necessary and sufficient amount of information needed for classification of an unpropagated virus on a case-by-case basis.

Rev Environ Contam Toxicol, 1995, 142, 119 - 47
Heavy metal toxicity testing in environmental samples; Kong IC et al.; The toxicity of heavy metals in the environment depends on a number of physicochemical and biological factors . The complexity of these relationships has encouraged the use of bioassays for direct measurement of the {table: see text} impact of toxic metals on selected test species . Fish and daphnid bioassays are well accepted by the scientific and regulatory communities, but their length (48 h or more) and the considerable time and effort needed to culture the test organisms make their application to sample screening problematical . Microbial and biochemical assays based on the inhibition of bioluminescence, enzyme activity, enzyme biosynthesis, growth, respiration, and heat production are typically faster and less expensive than the traditional and fish bioassays . Some of these tests approach or equal the sensitivity of daphnids to heavy metals . Since the soil acts as a sink for airborne and waste-applied metals, the uptake of metals by plants and the associated toxic impacts are important . Growth inhibition, enzyme induction, and production of stress proteins have been considered as toxicity end points . Enzymatic tests have been developed that are specific for heavy metal toxicity . Such tests can facilitate toxicity reduction evaluations . Detection of individual metals in the environment may eventually be possible using biosensors consisting of genetically engineered microorganisms . Direct solid-phase tests for soil, sediment, or sludge toxicity, using bacterial bioluminescence or enzyme activity as end points, have been developed . Such tests may complement traditional solid-phase toxicity tests using nematodes or earthworms as indicator organisms . Based on the work reviewed, we draw the following conclusions: 1 . The Microtox assay is sensitive to mercury but would fail to detect the toxicity of certain metals, such as cadmium . Among all the microbial assays reviewed, the bioassay based on growth inhibition of the alga Selenastrum capricornutum appears to give the lowest EC50s, similar to those seen for daphnid bioassays . 2 . Biosensors, using genetically engineered microorganisms, offer an elegant means of detecting the presence of specific heavy metals in environmental samples . However, at the present time, they are not designed for assessing heavy metal toxicity . 3 . The use of bioassays specific for heavy metal toxicity can be useful for directly assessing the bioavailability of these toxicants in environmental samples, thus avoiding the need for fractionation.+4

Planta, 1995, 196(3), 492 - 500
Age-dependent induction of pyruvate, orthophosphate dikinase in Mesembryanthemum crystallinum L; Fisslthaler B et al.; A full-length transcript for pyruvate, orthophosphate dikinase (PPDK; EC 2.7.9.1), has been characterized from Mesembryanthemum crystallinum . Under salt stress or with increasing age, this plant shows a transition from C3 to Crassulacean acid metabolism (CAM) . The PPDK plays a central role in gluconeogenesis during the light phase of CAM . The transcript is 3165 bases in length with a single open reading frame of 2739 nucleotides specifying a protein of molecular mass 103098, including a transit peptide of mass 7902 for chloroplast import . The protein shares 44-77% sequence identity with PPDK from C4-plants and microorganisms . Known functional and regulatory amino acids are conserved . Southern-type hybridizations indicated one copy or very few closely related copies of the gene per haploid genome . We investigated the induction of PPDK at the mRNA and protein levels, using the well characterized induction of a CAM-form of phosphoenol pyruvate carboxylase (PEPCase) as internal standard . During wilting of excised leaves PEPCase mRNA amounts increased strongly within 8 h . Under these conditions amounts of PPDK mRNA remained constant . Re-hydrating leaves from previously stressed plants led to a decrease in PEPCase and PPDK mRNA amounts . During salt stress, no correlation between PEPCase and PPDK was observed . Analysis of plants of different ages indicated that, even in well-watered plants, PPDK-specific protein and mRNA increased when the plants reached a certain age . In old plants, salt stress failed to further increase PPDK mRNA or protein levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Crit Rev Microbiol, 1995, 21(2), 123 - 52
Serodiagnosis of leishmaniasis; Kar K; Leishmaniasis is a spectrum of diseases ranging in severity from cutaneous (CL), post-kala-azar dermal (PKDL), and diffuse cutaneous (DCL) to mucocutaneous (MCL) and visceral (VL) infections that are endemic in 86 tropical and subtropical countries around the world, accounting for 75,000 deaths per year . Different forms of leishmaniases are generally caused by different distinct species of Leishmania having a digenetic life cycle alternating between an aflagellated amastigote form replicative within the macrophages of the host and a flagellated promastigote form that multiplies within the gut of the sandfly . VL, MCL, PKDL, DCL, and CL forms of the disease can be arranged on a priority basis in accordance with the humoral immune responses of host . Generally, the cell-mediated immunity, particularly the delayed-type hypersensitivity to leishmanial antigens, is associated with CL, MCL, PKDL, and cured VL cases . The serodiagnosis of leishmaniasis appears to be an alternative to parasite detection in biopsy samples either by the staining of amastigotes or by culturing the amastigotes, which transform to a promastigote form and replicate . A battery of immunological procedures have been developed or adapted to demonstrate either humoral or cell-mediated immune responses against Leishmania for diagnosis and epidemiological survey . The sensitivity and specificity of such diagnostic methods depend on the type, source, and purity of antigen employed, as some of the leishmanial antigens have common cross-reactive epitopes shared with other microorganisms, particularly Trypanosoma, Mycobacteria, Plasmodia, and Schistosoma . Serodiagnostic techniques for the detection of antileishmanial antibodies have been employed with about 72 to 100, 23 to 90, 83, and 33 to 100% success in VL, CL, MCL, and PKDL patients, respectively . The Leishmanin skin test (LST) is useful to detect MCL and CL, with about 100 and 84% success, respectively . In PKDL, the gradual fall of antileishmanial antibody titer to some extent and the rise of delayed hypersensitivity to the parasite antigen are the characteristic features associated with the chronicity of the disease . The use of whole promastigote as the source of antigens in the direct agglutination test (DAT) and immunofluorescent test (IFAT) gave cross-reactions with the sera of leprosy, tuberculosis, and African trypanosomiasis patients . Again, the use of cell-free extracts of promastigotes generally gave false positive results with the sera of normal human and Chagas' disease, leprosy, tuberculosis, and malaria patients in enzyme-linked immunosorbent assay (ELISA), dot ELISA, immunodiffusion, immunoelectrophoresis, and counter-current immunoelectrophoresis tests.(ABSTRACT TRUNCATED AT 400 WORDS)

Crit Rev Food Sci Nutr, 1995 Jan, 35(3), 231 - 62
Evaluation of the integrated time-temperature effect in thermal processing of foods; Hendrickx M et al.; In this review, current methods used to evaluate the integrated impact of time and temperature upon preserving a food product by a heat treatment are considered . After identifying the basic premise any preservation scheme shall meet, the central role of a feasible description for the heat activation kinetics of microorganisms, their spores, and other quality attributes are stressed . Common concepts to quantify a thermal process are presented . Shortcomings of the prevalent evaluation methods are highlighted and attention is given to the development, restrictions, and possibilities of time-temperature-integrators as "new" evaluation tools to measure the impact of a "classical" in-pack heat treatment and more modern heating techniques such as continuous processing of solid/liquid mixtures on foods.

Minerva Chir, 1995 Jan-Feb, 50(1-2), 115 - 9
{Our experience with a new material for skin graft areas}; Navissano M et al.; The authors describe a new method of medicating disepidermised areas from which a dermo-epidermic graft has been removed to cover burn areas or following post-traumatic loss of substance . This method consists of the use of a thin microfibrillar film of a polysaccharidic type, which serves as a temporary substitute for the skin, offering selective permeability, the possibility of transpiration and gaseous exchange, but at the same time being impermeable to liquids and microorganisms . A study was performed to evaluate the efficacy and tolerability of this new dressing, involving 30 patients of both sexes aged between 9 and 87 years old . The site, dimensions, and type of graft were assessed in each patient together with the duration of pain and the time taken for the lesion to heal . This study has highlighted the positive function performed by medication with microfibrillar film in facilitating the cicatricial process, achieving complete re-epithelisation within an average of 8-9 days, with a considerable reduction in pain and satisfactory esthetic and functional result . No collateral effects or complications relating to the use of this material are reported in any of the cases studied.

Int J Oral Maxillofac Implants, 1995 Jan-Feb, 10(1), 67 - 73
Microbiologic and clinical study of polytetrafluoroethylene membranes for guided bone regeneration around implants; Nowzari H et al.; This study determined the microbiota of the mucosa- and implant-facing parts of expanded polytetrafluoro ethylene augmentation material, and the influence of major periodontopathogens on the healing process associated with guided bone regeneration around dental implants . Seventeen patients with nine dehiscence and eight extraction defects were studied . Prior to surgery and at membrane removal, microbial morphotypes, total viable counts, and the occurrence of selected microbial species were examined by phase-contrast microscopy, nonselective and selective cultures, and DNA probes . Nine sites with submerged barrier membranes throughout the 9-month study were free of cultivable microorganisms and experienced significantly more osseous healing than eight sites with prematurely exposed membrane . Patients with few or no deep periodontal pockets demonstrated significantly fewer residual osseous defects than patients showing several pockets of increased depths . In addition, patients with prematurely exposed membranes revealed several deep periodontal pockets . Three patients with less than 1 mm of osseous gain yielded either Porphyromonas gingivalis or Actinobacillus actinomycetemcomitans . Peptostreptococcus micros occurred in high proportions in seven of the eight patients with premature membrane exposure and inadequate osseous healing . These findings associate putative periodontal pathogens with unsuccessful guided bone regeneration . The control of periodontal pathogens in the oral cavity prior to placement of barrier membranes around implants might increase the prognosis of osseous regeneration.

Annu Rev Immunol, 1995, 13, 459 - 86
Superantigens of mouse mammary tumor virus; Acha-Orbea H et al.; Superantigens (SAgs) are proteins of microbial origin that bind to major histocompatibility complex (MHC) class II molecules and stimulate T cells via interaction with the V beta domain of the T cell receptor (TCR) . Mouse mammary tumor virus (MMTV) is a milk-transmitted type B retrovirus that encodes a SAg in its 3' long terminal repeat . Upon MMTV infection, B cells present SAg to the appropriate T cell subset, which leads to a strong "cognate" T-B interaction . This immune reaction results in preferential clonal expansion of infected B cells and differentiation of some of these cells into long-lived memory cells . In this way a stable MMTV infection is achieved that ultimately results in infection of the mammary gland and virus transmission via milk . Thus, in contrast to many microorganisms that attempt to evade the host immune system (reviewed in 1), MMTV depends upon a strong SAg-induced immune response for its survival . Because of their ability to stimulate very strong T cell responses in MHC-identical mice, minor lymphocyte stimulatory (Mls) antigens, discovered more than 20 years ago, are now known to be SAgs encoded by endogenous MMTV proviruses that have randomly integrated into germ cells . The aim of this review is to combine the extensive biology of Mls SAgs with our current understanding of the life cycle of MMTV.

Reprod Nutr Dev, 1995, 35(3), 329 - 37
Effect of anaerobic fungi on glycoside hydrolase and polysaccharide depolymerase activities, in sacco straw degradation and volatile fatty acid concentrations in the rumen of gnotobiotically reared lambs; Fonty G et al.; Four naturally born lambs were placed in sterile isolators 24 h after birth, before the natural establishment of the cellulolytic microorganisms . At the age of 4 weeks, a cellulolytic bacterial population of approximately 10(8) cells g-1 of rumen contents was established by inoculation with a 10(-6) dilution of ruminal contents taken from an adult sheep . A pure culture of Neocallimastix frontalis MCH3 and Piromyces communis FL was inoculated into the rumen 5 months after birth and a stable population of 10(3)-10(4) zoospores g-1 developed; the cellulolytic bacteria and fungi established populations in the 4 lambs that were similar to those observed in conventional animals . The presence of fungi led to an increase in the activity of most of the glycoside and polysaccharide hydrolases of the particle-associated microbial populations . However, this effect was not accompanied by an increase in the in sacco degradation of wheat straw or an increase in the volatile fatty acid concentration in the rumen contents.

Adv Appl Microbiol, 1995, 40, 289 - 321
Detection, isolation, and stability of megaplasmid-encoded chloroaromatic herbicide-degrading genes within Pseudomonas species; Cork DJ et al.; Dicamba is used as a model system for microbial degradation of chloroaromatic benzoic acids . The detection, isolation, and stability of a megaplasmid within a Pseudomonas sp . is described as the first step in optimizing the growth of this microorganism and other microorganisms similar to it . A large plasmid, pDK1, consisting of approximately 250 kb, was purified from dicamba-degrading Pseudomonas sp . PXM . This plasmid was purified by the method of Allen (personal communication, 1994), which is a modified version of several that have been attempted for the isolation of large plasmids (Lee and Rasheed, 1990) . The restriction analysis of this plasmid (pDK1) from PXM . revealed many distinctive bands on agarose gel electrophoresis . Based on the preliminary restriction enzyme analysis, the estimated size of this plasmid is 250 kb, which could make it one of the largest procaryotic plasmids encoding for chloroaromatic degrading enzymes . Allen's methodology results in very high purity and reproducibility compared to the other methods used in this study . As described in this work, the method of Kado and Liu (1981) is easier to perform and results in a more reproducible plasmid preparation than the method of Casse et al . (1979) . Casse's protocol requires the use of a highly alkaline SDS solution (pH 12.45) in order to eliminate the chromosomal DNA . However, only incomplete removal of the chromosomal DNA results . Compared to the Casse et al . protocol, the Kado and Liu protocol requires the use of a highly alkaline solution (pH 12.6) and a high temperature (55-65 degrees C) to eliminate the chromosomal DNA . This results in a nearly complete removal of the chromosomal DNA . The high temperature treatment also quickly eliminates the RNA . Another advantage of the protocol of Kado and Liu over the protocol of Casse et al . is that the former uses phenol-chloroform extraction while the latter uses only phenol extraction . The phenol-chloroform extraction step denatures the DNA along with the proteins . In addition to this, the phenol-chloroform mixture minimizes the formation of a brown oxidation pigment that usually occurs with phenol extraction alone . Finally, the time needed to complete the Kado and Liu protocol is much shorter (2 hr) than the time needed to complete the Casse protocol (8 hr) . As described previously, a highly purified plasmid preparation with minimal chromosomal DNA was prepared by following the suggestions of L . Allen.(ABSTRACT TRUNCATED AT 400 WORDS)

Planta, 1995, 197(1), 1 - 10
Adenosine diphosphate glucose pyrophosphorylase genes in wheat: differential expression and gene mapping; Ainsworth C et al.; A full-length cDNA clone representing the large (shrunken-2) subunit of ADP-glucose pyrophosphorylase (AGP; EC 2.7.7.27) has been isolated from a cDNA library prepared from developing grain of hexaploid wheat (Triticum aestivum L., cv . Chinese Spring) . The 2084-bp cDNA insert contains an open reading frame of 1566 nucleotides and primer-extension analysis indicated that the 5' end is 10 nucleotides shorter than the mRNA . The deduced protein contains 522 amino acids (57.8 kDa) and includes a putative transit peptide of 62 amino acids (6.5 kDa) . The similarity of the deduced protein to the small subunit of AGP and to other AGP genes from plants and microorganisms is discussed . Northern hybridisation shows that the Agp1 genes (encoding the small subunit in the wheat endosperm) and the Agp2 genes (encoding the large subunit in the wheat endosperm) are differentially expressed in the wheat grain . Transcripts from both gene sets accumulate to high levels in the endosperm during grain development with the majority of the expression in the endopsperm rather than the embryo and pericarp layers . Although enzyme activity is detected in developing grains prior to 10 d post anthesis, only the Agp1 genes are active at this time (the Agp2 genes are not expressed until 10 d post anthesis) . The possibility that the enzyme expressed during early grain development is a homotetramer of small subunits is discussed . The Agp1 and Agp2 genes are arranged as triplicate sets of single-copy homoeoloci in wheat . The Agp2 genes are located on the long arms of chromosomes 1A, 1B and 1D, about 80 cM from the centromere . The Agp1 genes have been mapped to a position just distal to the centromere on the long arms of chromosomes 7A, 7B and 7D.

Ann Pharm Fr, 1995, 53(4), 155 - 62
{PCR: principles and prospects in clinical biology}; Billiald P et al.; In the short time it has been available, the Polymerase Chain Reaction (PCR) has been rapidly established as a powerful tool for the analysis of genes leading to a wide spread of its application in research . Its basic qualities (sensitivity, specificity and quickness) also offer facilities for its application to the detection and amplification of foreign and aberrant genes . Recent reports have already shown its ability to detect microorganisms and to identify genes related to molecular diseases . Therefore, its application to the diagnosis of infectious and genetic diseases is expected in the next future . However, some problems have to be solved before the use of this technology is routine in clinical chemistry.

Ann Biol Clin (Paris), 1995, 53(1-2), 25 - 8
Automated blood culture systems; Gutierrez J et al.; This review compares automated systems of blood culture for the detection of positive bottles, excluding mycobacteria . The performance of different systems is influenced by several key variables, including volume of the blood sample, the use of resins, shaking to increase the recovery of aerobic microorganisms, duration of incubation and final subculture . The Bactec, BacT/Alert, BioArgos and ESP systems require further study and technical improvement . There is no single ideal system of blood culture, and combinations of two or more methods are likely to provide the best results.

Ann Biol Clin (Paris), 1995, 53(1-2), 21 - 4
Clinical evaluation of the Vital system compared with the Hémoline diphasic method for the detection of aerobic blood cultures; Avril JL et al.; In a collaborative study at two university hospitals, the recovery of microorganisms and the speed of detection of microbial aerobic growth by the Vital system (bioMerieux) and a diphasic conventional blood culture system were compared . The Vital system monitors each blood culture bottle every 15 minutes to detect inactivation of fluorescent suspended in the broth medium due to microbial growth . A total of 1086 comparisons were made between the two systems, yielding a total of 117 isolates . Microorganisms were recovered more often from the Vital aerobic bottles (p < 0.05) . The Vital system detected 43% of the microorganisms within the first 12 hours of incubation whereas in the same time the conventional system detected only 5% of the microorganisms . The results demonstrate that the Vital system is a reliable, continuous monitoring, fully automated system and an attractive alternative to conventional blood culture methods.

Adv Enzyme Regul, 1995, 35, 43 - 53
Isolation and biological activities of signal transduction inhibitors from microorganisms and plants; Umezawa K; Microorganisms and plants are treasuries of secondary metabolites having unique structures and biological activities . We have isolated inhibitors of cellular signal transduction from them . Phosphatidylinositol turnover inhibitors include inostamycin, piericidins and echiguanines . Erbstatin and lavendustin A were isolated as tyrosine kinase inhibitors, and dephostatin was isolated as a tyrosine phosphatase inhibitor . Recently, we have isolated a new vinca alkaloid having anti-ras activity . These signal transduction inhibitors will be useful for mechanistic studies and suppression of cancer.

Stomatologiia (Mosk), 1995, 74(3), 52 - 5
{The microorganism count on impression materials following disinfection by dynamic plasma treatment}; Ostroukhova AA et al.; B . subtilis and B . cereus in concentrations under 10(5) mt, and of E . coli M-17 below 10(7) mt on different plaster materials die within fractures of a second after dynamic plasma processing at atmospheric pressure and at least one passing of the processed surface at a rate of 2.0 to 2.5 m/s at plasma flow power of 60 kw.

Probl Tuberk, 1995, (4), 40 - 2
{Possibilities of the use of gas-liquid chromatography in the identification of Nocardia microorganisms}; Shkarin AV et al.; By determination of fatty acid composition of bacterial cells, gas-liquid chromatography can quickly identify Nocardia microorganisms isolated from the infected material . The study of fatty acid spectrum of the reference and fresh cultures Nocardia has found their homogeneity . Such fatty acids as hexadecenoic, hexadecanoic, octadecenoic, octadecanoic and tuberculostearic acids occurred most frequently . Differential criteria are proposed for Nocardia microorganisms basing on gas-liquid chromatography data on fatty acid spectra from mycobacteria to other nonmycobacterial acid-fast microorganisms.

Aviakosm Ekolog Med, 1995, 29(3), 26 - 8
{Biotechnology manufacture as a possible source of environmental pollution and a risk factor for human health}; Pivovarov IuP et al.; The biotechnology-oriented quantitative criteria and a plan of primary sanitary hygienic evaluation of pathogenicity of microorganisms-producers were first established . New evidence of the negative effects of strains-producers on microbiocenosis and self-purification of soils and reservoirs were obtained . The requirement of an all-round hygienic assessment of microorganisms-producers consisting of two mandatory steps, i.e . the primary sanitary hygienic evaluation of pathogenicity of strains and the investigation of effects of these microorganisms on microbiocenosis and soil and reservoir self-purification has been substantiated.

Przegl Epidemiol, 1995, 49(1-2), 9 - 16
{Kawasaki disease}; Gliwinska E; Kawasaki disease (KD), first described in Japan in 1967 by Dr . Tomisaku Kawasaki, is an acute multi system vasculitis of infancy and early childhood characterised by high fever, rash, conjunctivitis, inflammation of the mucous membranes, erythematous induration of the hands and feet and cervical lymphadenopathy . Synonyms for Kawasaki disease include "Kawasaki syndrome" and "mucocutaneous lymph node syndrome" (MCLS, MLNS, MCLNS) . Kawasaki disease was initially presumed to occur only in Japan; but now this disease is known in the whole world . The first cases in the United States were reported in Hawaii in 1976 . In poland 5 cases were recognized, and first time described in 1981 . The etiology of Kawasaki disease remains unknown . Toxic, allergic and immunologic causes have been suspected, but most investigators favor an infectious cause or an immune response to an infectious agent . Among classes of microorganism suspected of causing Kawasaki disease were bacteria, leptospires, fungi, rickettsiae and a number of viruses . Recently, there has been considerable interest in the possibility, that Kawasaki disease is caused by RETROVIRUSES . Although the disease is generally benign and self-limited, about 20% of children develop coronary artery aneurysms . In 5% of cases, giant aneurysm/more then 8 mm/develop, predisposing the patient to acute coronary artery thrombosis, myocardial infarction and sudden death . This is the most serious complication of KD . Other manifestations of hearth involvement, include pericarditis, myocarditis, myocardial failure and mitral regurgitation . Besides this many other clinical findings are commonly noted in KD; such as: pneumonia, diarrhea, arthritis, aseptic meningitis, otitis media, obstructive jaundice, hydrops of gallbladder and others.(ABSTRACT TRUNCATED AT 250 WORDS)

Mol Plant Microbe Interact, 1995 Jan-Feb, 8(1), 172 - 6
GmN56, a novel nodule-specific cDNA from soybean root nodules encodes a protein homologous to isopropylmalate synthase and homocitrate synthase; Kouchi H et al.; We have isolated a novel nodule-specific cDNA clone, GmN56, from soybean root nodules . The expression of GmN56 was induced almost concomitantly with the onset of nitrogen fixation, together with leghemoglobin and other late nodulin genes . In situ hybridization studies demonstrated the localization of GmN56 mRNA in the bacterial infected cells of mature nodules . The predicted amino acid sequence of the GmN56 protein exhibits significant homology to those of LeuA (isopropylmalate synthase) of several microorganisms and NifV (putative homocitrate synthase) of nitrogen-fixing bacteria, suggesting that GmN56 encodes an enzyme catalyzing a reaction involving acetyl-CoA and alpha-keto acid as substrates.

Klin Lab Diagn, 1995 Jan-Feb, (1), 38 - 40
{Transport medium for pathogenic pseudomonads}; Zhoga LK et al.; A transporting medium was designed for the transportation and preservation for 5 to 7 days of material infected with agents of malleus and melioidosis . Foreign contaminating microorganisms gradually die in this medium, whereas solitary cells of malleus and melioidosis agents (100 bacterial cells per 0.1 ml) survive.

Kidney Int, 1995 Jan, 47(1), 88 - 95
Neuraminidase promotes neutrophil, lymphocyte and macrophage infiltration in the normal rat kidney; Marin C et al.; Neuraminidase (NA) is an enzyme produced by several microorganisms, which is capable of liberating sialic acid from glycoproteins and modifying cellular adhesion mechanisms . NA is considered a virulence factor in some bacterial species and has been implicated in the pathogenesis of acute poststreptococcal glomerulonephritis, a disease in which glomerular leukocyte infiltration is a prominent feature . We examined the effect of NA on kidney infiltration by neutrophils (PMN), T lymphocytes (TL) and monocyte-macrophages (MM) . Intravenous injection of NA resulted in an early increase in the number of PMN (1 hr, 3.42 +/- 0.19 cells/cgs, mean +/- SEM; 3 hr, 3.63 +/- 0.13; 6 hr, 2.9 +/- 0.24; controls, 1.53 +/- 0.18; P < 0.001) and MM (1 hr, 3.49 +/- 0.16; 3 hr, 4.02 +/- 0.2; 6 hr, 3.88 +/- 0.27; controls 1.43 +/- 0.14; P < 0.001) in the glomeruli, while TL increased later (24 hr, 2.29 +/- 0.14; 48 hr, 2.4 +/- 0.2; 72 hr, 2.16 +/- 0.15; controls 0.7 +/- 0.07; P < 0.001) . PMN and TL were also increased in the interstitium (up to ninefold for PMN and up to threefold for TL) . Following i.v . injection of 51Cr-labeled NA-treated leukocytes, renal radioactive uptake was significantly increased at all times tested (percent radioactivity/gram of tissue after PMN injection, 3 hr, 5.57 +/- 0.46, mean +/- SEM; 12 hr, 5.38 +/- 0.77; 60 hr, 6.51 +/- 1.1; controls, 1.26 +/- 0.17, 1.75 +/- 0.25, and 2.46 +/- 0.08, respectively; P < 0.001 in each case.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastroenterology, 1995 Jan, 108(1), 75 - 82
Mucosal expression by B7-positive cells of the 60-kilodalton heat-shock protein in inflammatory bowel disease; Peetermans WE et al.; BACKGROUND/AIMS: Heat-shock protein (Hsp) 60 is an immunodominant antigen of mycobacteria and other microorganisms that is highly homologous to its human counterpart . Hsp60 may provide a link between immunity to invading microorganisms and autoimmune diseases . METHODS: Expression of Hsp60 was studied by immunohistochemistry in gut resection specimens of patients with Crohn's disease (n = 14), ulcerative colitis (n = 7), acute self-limited colitis (infective type) (n = 5), and controls (n = 9) using the monoclonal antibodies LK1 and LK2 . RESULTS: A strong staining positivity for Hsp60 was observed in numerous mononuclear cells of the mucosa and submucosa in ileum and colon tissue biopsy specimens of patients with Crohn's disease from inflamed and healthy areas . In ulcerative colitis, Hsp60 expression was limited to the mucosa . In biopsy specimens from patients with acute self-limited colitis and controls, Hsp60-positive cells were absent or only present in low numbers and staining intensity was weak . Differentiation between mammalian and bacterial Hsp60 showed expression of the human homologue . Double staining for B7 and Hsp60 showed that Hsp60 was expressed by B7-positive cells . CONCLUSIONS: Human Hsp60 is strongly expressed by B7-positive antigen-presenting mononuclear cells in the mucosa of patients with inflammatory bowel disease and might play a role in the initiation or maintenance of the inflammatory process.

Pol J Pathol, 1995, 46(3), 179 - 85
Comparison of morphological and biochemical changes of BAL-isolated cells in experimental lung emphysema; Sulkowski S et al.; The aim of the study was to evaluate the protease and antiprotease activity in the fluid obtained from the culture of cells isolated from the lungs of animals with experimental emphysema . An attempt was made to correlate the results of biochemical examinations with adherence degree and ultrastructural changes of the surface of BAL-isolated cells . The experiment was carried out on male Wistar rats, of 180-220 g b.w . Two i.p . injections of BCG-vaccine (4 x 10(8) microorganisms) on the 1st and 14th day were applied as macrophage mobilizing and activating agent . Papain (2 mg/l ml/100 g b.w.) was given once i.t . on the 21st day . The animals were sacrificed on the 28th day of the experiment . We found a correlation between the increase in the cell adherence and ultrastructural changes (in SEM), suggesting an increased activity of the cells isolated from BCG-treated rats . In the culture medium of cells isolated from the rats which were given BCG or papain and BCG+papain we observed an increased base protease activity and decreased Cathepsin D activity comparing with the control group . Increased antitrypsin activity in the BCG and BCG+papain-treated rats and decreased antitrypsin activity in papain-treated rats only was observed, too . There was no obvious difference in the levels of the antiplasmin and antichymotrypsin activities between the groups . The present results indicate that activated pulmonary macrophages are one of the sources of the protease-antiprotease intraalveolar imbalance . However, an increased production of proteolytic enzymes may not be the only factor responsible for the progression of lung emphysema in BCG-treated rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adv Biochem Eng Biotechnol, 1995, 52, 27 - 58
Production of poly(hydroxyalkanoic acid); Lee SY et al.; Poly(hydroxyalkanoic acid) {PHA} is accumulated by numerous microorganisms as an energy reserve material under unbalanced growth conditions in the presence of excess carbon source . In spite of being a good candidate for biodegradable thermoplastics, their high price compared with conventional plastics currently in use has limited their availability in a wide range of applications . With the aim of reducing the high production cost of PHA, much effort is currently being devoted to improve productivity by employing various microorganisms and by developing efficient culture techniques . Several processes recently developed and employed for the production of PHA by various bacteria are described.

Zentralbl Gynakol, 1995, 117(9), 466 - 71
{Reactive and areactive actinomycosis infection of the female genitals and differentiation of pseudoactinomycosis}; Horn LC et al.; Actinomycotic infections of the female genital tract are rare . In relation of clinical symptoms and therapeutical implications, reactive and non-reactive infections can be distinguished . During a period of seven years we observed five reactive infections . All these cases with tubo-ovarian abscesses (TOA) were seen in women using intrauterine devices (IUD) for 9.8 years on average . 9.1% of all TOA in this period were caused by actinomyces . Ten cases showed a non-reactive infection (colonisation) . The frequency was 1.9% . In three cases pseudosulfurgranules (pseudoactinomycotic granules) were identified histologically by PAS-, Grocott-and Kossa-staining) . One case showed a bacterial infection of a mucinous cystadenofibroma of the ovary with colonization of microorganisms similar to cases of botryomycosis in lung and other organs . Reactive infections require antibiotic therapy . Reimplantation of IUD should be done after 4 to 8 weeks, even in areactive infections . In specimens with pseudosulfurgranules no therapy is necessary.

Ann N Y Acad Sci, 1994 Dec 15, 740, 346 - 61
Emerging infectious diseases in the United States, Improved surveillance, a requisite for prevention; Bryan RT et al.; Emerging infectious diseases such as prolonged diarrheal illness due to water-borne Cryptosporidium, hemorrhagic colitis and renal failure from food-borne E . coli O157:H7, and rodent-borne hantavirus pulmonary syndrome as well as reemerging infections such as tuberculosis, pertussis, and cholera vividly illustrate that we remain highly vulnerable to the microorganisms with which we share our environment . Prompt detection of new and resurgent infectious disease threats depends on careful monitoring by modern surveillance systems . This article focuses on five important elements of improved surveillance for emerging infections: 1) strengthening the national notifiable disease system, 2) establishing sentinel surveillance networks, 3) establishing population-based emerging infections programs, 4) developing a system for enhanced global surveillance, and 5) applying new tools and novel approaches to surveillance.

Clin Intensive Care, 1995, 6(4), 174 - 80
The role of the gastric reservoir in ventilator-associated pneumonia; Torres A et al.; Ventilator-associated pneumonia (VAP) is a common complication of mechanical ventilation with an incidence ranging from 9-70% and averaging around 25% . The pathogenesis of VAP requires abnormal oropharyngeal and gastric colonisation and then aspiration of these contents into the lower airways . Another co-existing mechanism could be direct oropharyngeal or lower airways inoculation of microorganisms through contaminated respiratory therapy equipment . Ventilator-associated pneumonia develops easily if aspiration or inoculation of microorganisms occur in patients with artificial airways and in whom mechanical, cellular and/or humoral defences are altered . Both host factors and treatments may alter pulmonary defence mechanisms; these too may contribute to the development of VAP . An alternative mechanism to explain VAP is bacterial translocation, although this mechanism is still under investigation . Figure 1 illustrates a schema of the pathogenesis of VAP . In this paper we review the possible role of the gastric reservoir in the aetiology of VAP, emphasising the following issues: 1 . Risk factors for gastric colonisation 2 . Clinical evidence of gastric aspiration to the lower airways in mechanically ventilated patients 3 . Clinical evidence and controversies surrounding the role of the gastric reservoir in ventilator-associated pneumonia 4 . The role of bacterial translocation as a mechanism for the development of VAP 5 . A summary of prophylactic measures.

J Biol Chem, 1994 Dec 9, 269(49), 31006 - 11
Sulfolobus acidocaldarius terminal oxidase . A kinetic investigation and its structural interpretation; Giuffre A et al.; The thermoacidophilic archaebacterium Sulfolobus acidocaldarius possesses a very unusual terminal oxidase . We report original kinetic experiments on membranes of this microorganism carried out by stopped flow, using time-resolved optical spectroscopy combined with singular value decomposition analysis . The reduced-oxidized kinetic difference spectrum of the Sulfolobus membranes is characterized by three significant peaks in the visible region at 605, 586, and 560 nm . The 605-nm peak and part of the 586-nm peak (cytochrome aa3-type quinol oxidase) are reduced synchronously by both ascorbate plus N,N,N',N'-tetramethyl-p-phenylendiamine (TMPD) and dithionite, and they are very rapidly oxidized by molecular oxygen . A second pool of cytochromes seems to contribute to the 586-nm peak which is not reduced by ascorbate plus TMPD and reacts very slowly with dithionite . The b-type cytochromes (560 nm peak) are reduced by both reductants and are essentially "non-autoxidizable" at room temperature . Only one CO binding site with spectral features, kinetic properties, and ligand affinity not very dissimilar from those of mammalian cytochrome oxidase can be detected in the ascorbate-reduced membranes . On the contrary, a second CO binding site having unusual properties for aa3 terminal oxidases can be detected in the dithionite-reduced membranes.

FASEB J, 1994 Dec, 8(15), 1314 - 25
The interleukin-1 family: 10 years of discovery; Dinarello CA; Ten years ago the cloning of two interleukin-1 molecules (IL-1 alpha and IL-1 beta) resolved the question of whether a single polypeptide could evoke a wide variety of biological effects . During the past decade, the biology of IL-1 has greatly expanded our understanding of how the host responds to external challenges, such as injury and infection, as well as its role in several diseases . We learned of the remarkable potency of IL-1 in the femtomolar range and of its ability to induce a response by triggering only one or two receptors per cell . Unexpectedly, the IL-1 family of genes, receptors and associated molecules have been linked to those of Drosophila, nematodes, and microorganisms and IL-1 signal transduction is similar to that observed after cellular stress . The cloning of IL-1 opened other avenues of fundamental biological interest . For example, in addition to the two agonist molecules IL-1 alpha and IL-1 beta, a third member of the IL-1 gene family is a specific, high affinity receptor antagonist (IL-1 receptor antagonist) . That this third member of the IL-1 family inhibits the other two is characteristic of the tight control over production and activity exerted on IL-1 . Although IL-1 contributes to the pathogenesis of many diseases, a small amount appears to be needed to combat infection and initiate healing processes . This article highlights 10 years of discoveries on IL-1.

FASEB J, 1994 Dec, 8(15), 1248 - 59
The animal fatty acid synthase: one gene, one polypeptide, seven enzymes; Smith S; The animal fatty acid synthase comprises two multifunctional polypeptide chains, each containing seven discrete functional domains, juxtaposed head-to-tail such that two separate centers for fatty acid assembly are formed at the subunit interface . The kinetics and specificities of the component enzymes are well adapted to ensure that, at each of the two centers, the iterative condensation of an acetyl moiety with successive malonyl moieties and complete reduction of the beta-keto intermediates normally results in the formation of palmitic acid as the major product . Nevertheless, utilization of alternative substrates and alternative chain-terminating mechanisms can extend the range of products to include branched-chain, odd carbon-numbered, and shorter chain-length fatty acids . The potential of this multifunctional form of molecular architecture for the elaboration of more complex natural products has been further exploited in microorganisms that, by the use of different fatty acid synthase "modules" that perform variable beta-carbon processing at successive elongation steps, generate a structurally diverse family of polyketides retaining keto, hydroxyl, enoyl, or alkyl functions at specific positions in the carbon chain.

Clin Orthop, 1994 Dec, (309), 44 - 55
Treatment of the infected total knee arthroplasty with insertion of another prosthesis . The effect of antibiotic-impregnated bone cement; Hanssen AD et al.; Eighty-six patients with 89 infected total knee arthroplasties were treated with insertion of another prosthesis . Treatment was not according to an established protocol for parameters, such as delay between removal of the infected prosthesis and insertion of the new prosthesis, duration of antibiotics, use of antibiotic-impregnated cement spacers or beads, and use of antibiotic-impregnated cement for prosthetic fixation at revision surgery . Final followup averaged 52 months (range, 6-126 months) . Complications occurred in 30 (33.7%) knees, with recurrent deep infection developing in 10 (11.24%) knees . Patient age, medical diagnosis, type of microorganism, duration of parenteral antibiotics, delay between the resection and revision surgery, and use of antibiotic-impregnated cement spacers or beads were not correlated with the cure rate of infection . Use of antibiotic-impregnated bone cement for prosthesis fixation at revision surgery was the only variable that correlated with the cure rate of deep infection . Seven (28%) of the 25 knees without antibiotic-impregnated cement for prosthesis fixation developed recurrent infection compared with 3 (4.7%) of 64 knees with antibiotic-impregnated cement for prosthesis fixation . This difference was statistically significant (p = 0.0025, log-rank test).

J Immunol, 1994 Dec 1, 153(11), 5316 - 20
Association of Gm allotypes with the antibody response to the outer membrane proteins of a common upper respiratory tract organism, Moraxella catarrhalis; Goldblatt D et al.; Previously, Gm allotypes have been shown to influence human serum Ig subclass levels as well as the Ab levels achieved after Ag stimulation . The majority of the latter studies have focused on Ab responses to polysaccharide Ags . In this study, we have investigated the relationship between Gm allotypes and naturally occurring serum Ab levels to a bacterial protein Ag, the outer membrane proteins of a common microorganism, Moraxella catarrhalis . In the sera of 160 patients having chronic/recurrent sinusitis, there was a highly significant correlation between the level of specific anti-M . catarrhalis IgG3 level and certain Gm phenotypes . After additional investigation, we found that the presence of G3m(21) homozygosity correlated significantly with lower levels of Ag-specific IgG3 . Specific anti-M . catarrhalis IgG3 levels were found to be independent of total serum IgG3 concentrations, and there was no correlation between the serum level of IgG3 and any Gm phenotype . Total IgG and IgG2 that were specific for pneumococcal cell wall polysaccharide also were measured in this group of patients, and no correlation was found between the naturally occurring IgG2 subclass levels to pneumococcal cell wall polysaccharide and the interactive effect of G2m(23) (syn: G2m(n)) and Km(1) . Gm allotypes may influence Ab responses other than the anti-carbohydrate responses and, therefore, should be taken into account when investigating IgG subclass responses to protein Ags.

Fertil Steril, 1994 Dec, 62(6), 1250 - 4
Detection of Chlamydia trachomatis in semen by antibody-enzyme immunoassay compared with polymerase chain reaction, antigen-enzyme immunoassay, and urethral cell culture; Wolff H et al.; OBJECTIVE: To compare the results obtained by four different techniques for the detection of Chlamydia trachomatis in the male genital tract . DESIGN: Prospective study . SETTING: Andrology unit of a university hospital . PATIENTS: Male infertility patients . INTERVENTIONS: Analysis of semen samples and urethral swabs for the presence of C . trachomatis by recombinant antibody-enzyme-linked immunosorbent assay (rELISA), polymerase chain reaction (PCR), antigen-enzyme immunoassay (EIA) and McCoy cell culture . MAIN OUTCOME MEASURE: Detection of C . trachomatis . RESULTS: In 57 of 205 semen samples (27.8%) immunoglobulin A-antibodies against C . trachomatis were found . In contrast, only 1 of 56 semen samples (1.8%) was positive for C . trachomatis-DNA by PCR, only 1 of 139 semen samples (0.7%) was positive by antigen-EIA, and only 4 of 173 urethral swabs (2.3%) grew C . trachomatis in cell culture . CONCLUSIONS: The discrepancy of positive results found by the antibody-rELISA and direct methods for the detection of C . trachomatis indicates successful eradication of the microorganism in > 90% of antibody-positive men . Therefore, detection of antibodies against C . trachomatis in seminal plasma appears to be of limited diagnostic value.

Am J Respir Crit Care Med, 1994 Dec, 150(6 Pt 2), S147 - 54
Structure of the azurocidin, proteinase 3, and neutrophil elastase genes . Implications for inflammation and vasculitis; Jenne DE; The granule-associated elastase homologues neutrophil elastase (NE), proteinase 3 (PR3), and azurocidin (AZU) are involved in immune defense reactions of neutrophils and monocytes . Proteinase 3 and NE contribute to the destruction and elimination of microorganisms, cleave elastin and other proteins of connective tissues, and generate chemotactic activities by forming alpha 1-proteinase inhibitor (alpha 1-PI) complexes . Azurocidin is cytotoxic to certain microorganisms and chemotactic to monocytes . All three proteins are produced and packaged into azurophil granules in large quantities during neutrophil development . The genes encoding AZU, PR3, and NE are closely clustered in this sequence within 50 kb of genomic DNA and have the same transcriptional orientation . All three genes show the same exon-intron organization as neutrophil cathepsin G, mast cell chymase 1, and the lymphocyte serine proteases, granzymes A, B, and H . The AZU-PR3-NE gene cluster was mapped to the telomeric region on the short arm of human chromosome 19 (19p13.3), whereas cathepsin G, lymphocyte granzymes B and H, and mast cell chymase 1 are organized as a separate gene cluster on chromosome 14q11.2 . Neutrophil-derived serine proteases are widely regarded as pathogenic factors in degenerative and inflammatory diseases with abnormal tissue catabolism . Autoantibodies against PR3 are an obligate feature in the pathogenesis of Wegener's granulomatosis, a systemic autoimmune vasculitis . In addition, PR3 appears to regulate growth and terminal differentiation of the myelomonocyte lineage . Future investigations will clarify whether allelic variations in the AZU-PR3-NE locus predispose patients to increased degradation of elastic fibers, as in pulmonary emphysema, and to the formation of autoantibodies against PR3 in patients with Wegener's granulomatosis.

Arch Pediatr Adolesc Med, 1994 Dec, 148(12), 1327 - 30
Fine needle aspiration in the evaluation of children with lymphadenopathy; Buchino JJ et al.; OBJECTIVE: To evaluate fine needle aspiration of enlarged lymph nodes in children . DESIGN: Retrospective study of children who were referred for fine needle aspiration of a palpable lymph node that was of concern to their clinicians . SETTING: Large, urban, tertiary care pediatric hospital . SUBJECTS: One hundred nineteen patients (123 cases) aged 10 months through 21 years during the 30-month period from January 1990 to June 1992 . RESULTS: Aspirated material in 13 cases (10.6%) was deemed inadequate for cytologic diagnosis . In the remaining 110 cases, five aspirates revealed malignancy: two patients had Hodgkin's disease, one had non-Hodgkin's lymphoma, one had a leukemic infiltrate, and one had rhabdomyosarcoma . The findings in two cases were suspicious for malignancy, but the lymph nodes were found to be benign on excisional biopsy . No false-negative findings for malignancy were detected . The conditions of patients in the remaining 103 cases were diagnosed as a benign process, most commonly reactive lymphadenitis . Of 57 aspirates cultured, eight (14%) were positive for a microorganism . No significant complications were encountered in any of the 123 cases . CONCLUSION: Fine needle aspiration of enlarged lymph nodes in children is a safe, reliable (accuracy, 98%) procedure that often obviates the need for an excisional biopsy.

Genetics, 1994 Dec, 138(4), 1351 - 63
Sampling theory for cytonuclear disequilibria; Asmussen MA et al.; We examine the statistical properties of cytonuclear disequilibria within a system including one diploid nuclear locus and one haploid cytoplasmic locus, each with two alleles . The results provide practical guidelines for the design and interpretation of cytonuclear surveys seeking to utilize the novel evolutionary information recorded in the observed pattern of cytonuclear associations . Important applications include population studies of nuclear allozymes in conjunction with genes from mitochondria, chloroplasts, or cytoplasmically inherited microorganisms . Our attention focuses on the allelic and genotypic disequilibria, which respectively measure the nonrandom associations between the cytotypes and the nuclear alleles and genotypes . We first derive the maximum likelihood estimators and their approximate large sample variances for each disequilibrium measure . These are each in turn used to set up an asymptotic test of the null hypothesis of no disequilibrium . We then calculate the minimum sample sizes required to detect the disequilibria under specified alternate hypotheses . The work also incorporates the deviation from Hardy-Weinberg equilibrium at the nuclear locus, which can significantly affect the results . The practical utility of this new sampling theory is illustrated through applications to two nuclear-mitochondrial data sets.

Oral Microbiol Immunol, 1994 Dec, 9(6), 335 - 44
Gingival crevicular fluid antibody to Actinobacillus actinomycetemcomitans in periodontal disease; Ebersole JL et al.; We identified antibody isotypes and subclass proportions in gingival crevicular fluid to understand the potential protective ability of these antibodies towards infection with Actinobacillus actinomycetemcomitans . Immunoglobulin G (IgG) 1-4 antibody levels to A . actinomycetemcomitans serotype b were quantified in serum and gingival crevicular fluid from 20 periodontitis patients who had at least one subgingival plaque sample with cultivable A . actinomycetemcomitans . The subclass antibody levels in the patients' sera were IgG1 = IgG2 > IgG3 > IgG4 . A portion of the gingival crevicular fluid samples had IgG (15.7%; range: 0-52%) and IgA (2.5%; range: 0-15%) antibody that was significantly elevated compared with serum . Gingival crevicular fluid samples with elevated IgG antibody were analyzed for the subclass distribution and showed elevated IgG3 (58%), IgG4 (35%), IgG1 (25%) and IgG2 (25%) antibody in the gingival crevicular fluid . These results demonstrated a characteristic distribution of both serum and gingival crevicular fluid IgG subclass responses to A . actinomycetemcomitans . We also examined the sites with elevated antibody in each subclass for the presence of A . actinomycetemcomitans in the subgingival microbiota . The results showed that > 95% of sites with elevated IgG4 were colonized, whereas < 50% of sites with elevated IgG2 demonstrated this microorganism . IgG2 and IgG4 levels were primarily elevated in diseased sites, whereas IgG4 elevations were absent in healthy sites . The frequency and distribution of antibody in the gingival crevicular fluid as related to colonization with this microorganism were consistent with localized host-parasite interactions at individual tooth sites . The relative subclass distribution of elevated gingival crevicular fluid antibody was shown to be IgG3 > IgG4 > IgG2 = IgG1 . These antibody types suggest that the potential exists for this local antibody to A . actinomycetemcomitans to play an important role in the gingival sulcus in relationship to colonization and clinical presentation.

Appl Environ Microbiol, 1994 Dec, 60(12), 4544 - 52
Characterization of a psychrotrophic Arthrobacter gene and its cold-active beta-galactosidase; Trimbur DE et al.; Enzymes with high specific activities at low temperatures have potential uses for chemical conversions when low temperatures are required, as in the food industry . Psychrotrophic microorganisms which grow at low temperatures may be a valuable source of cold-active enzymes that have higher activities at low temperatures than enzymes found for mesophilic microorganisms . To find cold-active beta-galactosidases, we isolated and characterized several psychrotrophic microorganisms . One isolate, B7, is an Arthrobacter strain which produces beta-galactosidase when grown in lactose minimal media . Extracts have a specific activity at 30 degrees C of 2 U/mg with o-nitrophenyl-beta-D-galactopyranoside as a substrate . Two isozymes were detected when extracts were subjected to electrophoresis in a nondenaturing polyacrylamide gel and stained for activity with 5-bromo-4-chloro-indolyl-beta-D-galactopyranoside (X-Gal) . When chromosomal DNA was prepared and transformed into Escherichia coli, three different genes encoding beta-galactosidase activity were obtained . We have subcloned and sequenced one of these beta-galactosidase genes from the Arthrobacter isolate B7 . On the basis of amino acid sequence alignment, the gene was found to have probable catalytic sites homologous to those from the E . coli lacZ gene . The gene encoded a protein of 1,016 amino acids with a predicted molecular mass of 111 kDa . The enzyme was purified and characterized . The beta-galactosidase from isolate B7 has kinetic properties similar to those of the E . coli lacZ beta-galactosidase but has a temperature optimum 20 degrees C lower than that of the E . coli enzyme.

Microbiologia, 1994 Dec, 10(4), 423 - 8
{In vitro tests of the antagonistic behavior of Trichoderma spp . against pathogenic species of the horticultural region of La Plata, Argentina}; Monaco C et al.; The antagonistic properties of seven Trichoderma species in front of the pathogens Fusarium oxysporum, F . equiseti, F . solani, Sclerotinia sclerotiorum, S . minor, Rhizoctonia sp . and Sclerotium rolfsii was evaluated in vitro . Those microorganisms were isolated from horticultural soils of La Plata in order to test the antagonistic-pathogenic relationship . Dual cultures on PDA 2% were used . All the species of Trichoderma grew in the culture medium with a colonization value higher than 50% . Differences in the antagonistic behaviour of the pathogens were observed depending on the species with which they interacted . The presence of diffusible metabolites to the medium was demonstrated in almost 80% of the pathogens antagonists tested.

Microbiologia, 1994 Dec, 10(4), 413 - 22
Diversity of actinomycetes and fungi on seaweeds from the Iberian coasts; Genilloud O et al.; As a part of a screening program for natural products from microorganisms, 465 actinomycetes strains and 278 fungal strains were isolated from 44 seaweed specimens (Rhodophyta and Phaeophyta), collected in the Iberian peninsula seashore (Atlantic and Mediterranean coasts) . Six different isolation procedures were followed, and seven isolation media were used, some of which included seawater in their composition . The isolated microorganisms were identified to the level of species or genus by microscopic morphology . Determination of species of Streptomyces was performed through total fatty acid analysis by gas chromatography . Richness and diversity of the Streptomyces and actinoplanetes species isolated from the seaweeds are compared, taking into account the geographic location of the samples . Most of the fungi recovered from these samples were terrestrial, although several marine species (Dendryphiella arenaria, Dendryphiella salina, Varicosporina ramulosa, Corollospora intermedia and Asteromyces cruciatus) were also isolated.

Microbiologia, 1994 Dec, 10(4), 331 - 42
Forty years of screening programmes for antibiotics; Mochales S; The article gathers the reflections on the experiences of forty years doing research on the screening of natural product in the pharmaceutical industry . Over those years new technologies have improved the methodology . However, the steps followed in such a research are the same: the isolation and cultivation of microorganisms; the definition of assays with well defined targets; the demonstration of their efficacy for the discovery and selection of active substances produced by microorganisms; the classification and structural determination of the new products; and the study of their therapeutical efficiency . Examples of the processes which led to the production of several antibiotics (fosfomycin, cefoxitin and thienamycin) are described . One important lesson that the author has learnt is that microorganisms have unique fingerprints and that generalization should be avoided in the planning of this work.

Biosci Biotechnol Biochem, 1994 Dec, 58(12), 2299 - 300
Cloning and sequencing of a Synechococcus gene encoding a protein very similar to mammalian aldehyde dehydrogenases; Kashiwagi S et al.; We report cloning and sequencing of a gene encoding a putative aldehyde dehydrogenase in Synechococcus sp . PCC7942 . It was found that this phototrophic microorganism has a protein very similar to mammalian class-3 aldehyde dehydrogenases . A mutant strain lacking this gene was hypersensitive in growth to an aromatic aldehyde.

Curr Microbiol, 1994 Dec, 29(6), 323 - 9
Rapid purification of native SecA from Escherichia coli: development of a new affinity chromatography procedure; Kiser KB et al.; The SecA protein occupies a pivotal position in the public protein export pathway in Escherichia coli . The multifunctional SecA protein recognizes cytoplasmic factors associated with export including the presecretory protein and targets the complex to the inner membrane, where it acts in the early stages of protein translocation . The ability of SecA to bind ATP was the basis for the development of a novel, rapid purification scheme involving a single chromatographic step . Affinity chromatography was carried out on Red Sepharose CL-6B . The SecA present in crude extracts of E . coli binds strongly to this dye-ligand matrix, and active protein was purified to greater than 90% homogeneity . The protein isolated by this procedure retained the previously described ATPase and RNA-binding activities of SecA . This approach should permit the rapid purification of SecA homologs from a variety microorganisms.

J Diarrhoeal Dis Res, 1994 Dec, 12(4), 287 - 9
Role of different methods for the detection of diarrhoeal pathogens in HIV-infected patients in Brazil; Belo MT et al.; To evaluate the ability of different diagnostic methods for the detection of AIDS-related diarrhoeal pathogens in developing countries, we studied 40 HIV-infected patients with diarrhoea . All patients were subjected to stool examinations for parasites, stool culture and peroral jejunal biopsy . Jejunal specimens were processed for histological examination with several stains and for transmission electron microscopy (TEM) . Jejunal juice and mucosa were cultured . An aetiologic agent was found in twenty patients . Eleven stool specimens were positive for parasites and stool culture was positive in three patients . The enteropathogens detected by these two methods included every microorganism amenable to treatment . Histological examination revealed four agents not previously identified . TEM added to diagnosis in only two patients . All cultures of jejunal mucosa and jejunal juice were negative, even when stool culture was positive . We conclude that a minimal investigation consisting of stool examination for parasites and stool culture is a cost-effective strategy in the management of AIDS-related diarrhoea in developing countriesPIP: The authors report findings from their evaluation of the ability of different diagnostic methods to detect AIDS-related diarrheal pathogens in developing countries . 40 HIV-infected patients with diarrhea participated in the study, having their stools examined for parasites and submitting to stool culture and peroral jejunal biopsy . Jejunal specimens were processed for histological examination with several stains and for transmission electron microscopy (TEM) . Jejunal juice and mucosa were cultured . An etiologic agent was found in 20 patients, with 11 stool specimens positive for parasites and stool culture positive in three patients . The enteropathogens detected by these two methods included every microorganism amenable to treatment . Histological examination revealed four agents not previously identified . TEM added to diagnosis in only two patients . All cultures of jejunal mucosa and jejunal juice were negative, even when stool culture was positive . The authors conclude that a minimal investigation consisting of stool examination for parasites and stool culture is a cost-effective strategy in the management of AIDS-related diarrhea in developing countries .

J Antimicrob Chemother, 1994 Dec, 34(6), 1047 - 50
Amoxycillin causes an enhanced uptake of metronidazole in Actinobacillus actinomycetemcomitans: a mechanism of synergy; Pavicic MJ et al.; We investigated the influence of sub-inhibitory concentrations amoxycillin on metronidazole uptake of the metronidazole-susceptible facultative microorganism Actinobacillus actinomycetemcomitans . The rate of metronidazole uptake by bacterial cells simultaneously incubated with amoxycillin was higher than uptake in cells incubated with metronidazole alone . This phenomenon may explain the recently reported in-vitro synergic interaction between metronidazole and amoxycillin against A . actinomycetemcomitans.

J Chemother, 1994 Dec, 6(6), 383 - 7
Increased beta-lactamase activity in Branhamella catarrhalis after exposure to amoxicillin and clavulanic acid; Bedenic B et al.; Branhamella catarrhalis, previously regarded as a harmless member of the normal nasopharyngeal flora, has periodically been implicated as the major pathogen in representative cases of a variety of infections such as sinusitis, pneumonia, septicemia and meningitis . In addition, beta-lactamase production of these microorganisms, first described in 1977, has been reported with increasing frequency, up to 80% . The first-choice drug for the therapy of the infections caused by beta-lactamase producing strains of B . catarrhalis is amoxicillin combined with clavulanic acid . The aim of our work was to determine the influence of amoxicillin and clavulanic acid on the biosynthesis of beta-lactamase of B . catarrhalis . Our results point out that the combination of amoxicillin and clavulanic acid produces only a slight increase in enzyme activity in 5003 and 462 strains . Clavulanic acid alone caused no increase in enzyme production . Ravasio strain showed no increase in enzyme formation after exposure to antibiotics.

J Dairy Sci, 1994 Dec, 77(12), 3608 - 17
Effects of reduced phenolic acids on metabolism of propionate and palmitate in bovine liver tissue in vitro; Cremin JD Jr et al.; Benzoic acid, 3-phenylpropionic acid, trans-cinnamic acid, and 3-(4-hydroxyphenyl)propionic acid in ruminal fluid are presumed to be the products of chemical reduction of dietary phenolic monomers by ruminal microorganisms . Effects of reduced phenolics on metabolism in bovine liver tissue were evaluated by measurement of 1) conversion of propionate to glucose and CO2, 2) conversion of palmitate to oxidized products, and 3) leakage of lactate dehydrogenase from liver slices in vitro . In Experiment 1, .4 mM benzoic, 3-phenylpropionic, trans-cinnamic, or 3-(4-hydroxyphenyl)propionic acids decreased conversion of propionate to glucose and decreased conversion of palmitate to total oxidation products . At .2 mM, 3-(4-hydroxyphenyl)propionic acid did not inhibit conversion of propionate to glucose compared with that of controls, but the other reduced phenolics did . In Experiment 2, the same reduced phenolics inhibited conversion of propionate to glucose . Of the reduced phenolics tested, cinnamic acid inhibited conversion of propionate to glucose at the lowest concentration, .1 mM . Additionally, when present at > or = .4, .1, or .005 mM, benzoic, 3-phenylpropionic, or trans-cinnamic acids, respectively, increased leakage of lactate dehydrogenase from liver tissue . The reduced phenolics tested, which are representative of those in ruminal fluid, inhibited metabolism of bovine liver tissue in vitro at supraphysiological concentrations . Data at physiological concentrations were inconclusive.

Acta Med Port, 1994 Dec, 7 Suppl 1, S61 - 6
Cerebral toxoplasmosis after renal transplantation . Case report and review; Da Cunha S et al.; Infection caused by Toxoplasma gondii is a frequent event in Portugal . When this occurs in immunocompetent individuals, it is rarely a matter of concern; the contrary occurs with immunosuppressed patients or in pregnancy . Transplant patients are treated with immunosuppressive drugs which mainly disturb their mechanisms of cellular immunity, and that opens the way to infections by opportunistic intracellular microorganisms . We recently treated a renal transplant patient who suffered from cerebral toxoplasmosis, and this provided an opportunity for a review of the other 20 patients reported in medical literature to date.

Pathologica, 1994 Dec, 86(6), 659 - 64
{Disseminated Pneumocystis carinii infection: clinico-pathologic findings in an AIDS patient}; Valdes E et al.; Pneumocystis carinii pneumonia (PcP) is the most frequent cause of death in AIDS patients . Systemic diffusion of this microorganism is a rare event, mostly reported in patients receiving prophylactic aerosol therapy . The case here described is relative to a 29 years old man with AIDS, dead short by after hospital admission . Radiological and ecoscan examinations revealed structural subversion of liver and spleen, with frequent parenchymal calcification . Post mortem histological examination of lung, liver, spleen, heart, bone marrow, lymph nodes, kidney and hypophysis identified the presence of Pc, confirmed by monoclonal specified antibody immunostaining.

Braz J Med Biol Res, 1994 Dec, 27(12), 2803 - 20
Detection of infectious disease agents in tissue by immunocytochemistry; Bacchi CE et al.; 1 . Immunocytochemical procedures have played an increasingly larger role in the identification of infectious disease agents in tissue sections owing to the increased availability and specificity of antibody reagents, the great sensitivity of the methods, and the relative facility with which the studies are performed . 2 . Immunocytochemical methods can be applied to routine formalin-fixed tissue for the detection of infectious agents such as viruses, bacteria, fungi, and protozoa among other microorganisms for diagnostic and research purposes.

Eur J Gastroenterol Hepatol, 1994 Dec, 6 Suppl 1, S17 - 21
Morphological aspects of the cytotoxic action of Helicobacter pylori; Taniguchi Y et al.; OBJECTIVE: To morphologically investigate the cytotoxic action of Helicobacter pylori on gastric mucosal cells . METHODS: Twenty biopsy specimens were obtained from the antrum and greater curvature of the upper body of the stomach, and examined by electron microscopy to elucidate the process of mucus cell injury induced by H . pylori . RESULTS: Only H . pylori colonies in intimate contact with the mucosal cells caused various cell alterations, including loss of microvilli, mucus depletion, cell membrane injury and degeneration of the cytoplasm . In contrast, H . pylori that were not in contact with the mucosa had no effect on the surface mucus cells . CONCLUSIONS: The results of this study suggested the following mechanism of H . pylori-induced gastric mucosal injury . Intimate contact between H . pylori and the epithelial cell is necessary for cytotoxic action . During the process of cytotoxic action, degradation of the mucous gel layer and the glycocalyx are first caused by the proteolytic enzymes produced by H . pylori . Then the microorganism approaches the surface mucus cell, making intimate contact with the cell surface . Finally, H . pylori adheres directly to the cell membrane, effecting direct action of the toxins on the cell membrane . Subsequently, the degenerative changes induced destroy the cell membrane, resulting in degeneration of the cell itself.

Tierarztl Prax, 1994 Dec, 22(6), 592 - 5
{Lymph node cytology}; Hirschberger J; The cytological preparation of a lymph node is a relatively simple technique . A fine needle aspirate is smeared as a blood sample and stained with a hematological method, Wright-stain or Diff-Quik . The microscopical examination can be completed in a few minutes . The cytology of a lymph node is a valuable diagnostical step for the classification of a lymphadenopathy . Reactive hyperplasia, forms of lymphadenitis, primary or metastatic neoplasias, microorganisms and parasites can be diagnosed.

Schweiz Rundsch Med Prax, 1994 Nov 22, 83(47), 1303 - 8
{Pathogenesis of infectious endocarditis}; Eggimann P et al.; The principles of pathogenesis of infective endocarditis are reviewed . Predisposing factors include not only rheumatic and congenital, but also degenerative cardiopathies, such as valvulopathy, and some extracardial factors of increasing importance . These abnormalities promote the development of nonbacterial thrombotic vegetations, which may become infected when bacteremia occurs . The ability of some microorganisms to produce an infective endocarditis is related to their capacity of adherence to valvular tissue . The pathogenesis of the infected vegetations explains most of the pathophysiologic mechanisms responsible for the variety of the clinical manifestations of infective endocarditis.

J Biol Chem, 1994 Nov 18, 269(46), 28997 - 9002
Covalent attachment of human complement C3 to IgG . Identification of the amino acid residue involved in ester linkage formation; Sahu A et al.; C3 (native complement component 3) plays a central role in the activation of complement and in the transport and processing of immune complexes . Proteolytic activation of C3 exposes a highly reactive thioester bond which preferentially reacts with the hydroxyl groups of acceptor molecules on activators such as immune complexes or carbohydrates on microorganisms . Recently, a C3 attachment site has been localized on the CH1 domain of IgG1 between Val134 and Lys156 . We have synthesized a series of peptide analogs of this region to identify the preferred residue for C3b (the proteolytically activated form of C3) attachment . The parent peptide included all 6 hydroxyl-containing amino acids present in the proposed binding site and was highly reactive with activated C3 . The C3b-peptide complex was sensitive to hydroxylamine as was C3b-IgG indicating that both were ester-linked . The kinetic profile of hydrolysis of the C3b-peptide complex under physiologic conditions was found to be nearly identical to the profiles of C3b-IgG, C3b-IgG1, and C3b-glycerol complexes . Site-specific amino acid substitution of threonine and serine residues in the peptide indicated that, in contrast to the attachment site in C4b, little or no attachment occurred at serine residues . The threonine corresponding to Thr144 in the CH1 domain of IgG was found to be the major acceptor site for C3b . Thr148 was the second most reactive site on the peptide, but this residue is buried in native IgG.

Carbohydr Res, 1994 Nov 15, 264(2), 237 - 51
Transglucosylation with 6'-chloro-6'-deoxysucrose and immobilized isomaltulose-producing microorganisms using 2,2-dimethyl-1,3-dioxolane-4-methanol and its related compounds as acceptors . Steric and chemical requirement of the glucosyl acceptor; Kakinuma H et al.; Enantioselective and diastereoselective alpha-D-glucosylation of 2,3-O-isopropylidene-erythritol was observed in transglucosylation with a synthetic donor using three kinds of immobilized isomaltulose-producing microorganisms . Several related compounds, including an 2,3-O-isopropylidenated aldotetrose dimethyl dithioacetal and an aldotetronic acid ester were also glucosylated in moderate or good yield, depending on the microorganism utilized . Steric as well as functional group factors are discussed in relation to the substrate specificity of the glucosyl acceptor.

J Biol Chem, 1994 Nov 4, 269(44), 27280 - 5
Assessment of the contribution of the cytochrome b moiety of the NADPH oxidase to the transmembrane H+ conductance of leukocytes; Nanda A et al.; Phagocytic cells can kill microorganisms by synthesizing superoxide . Activation of the NADPH oxidase that generates superoxide is accompanied by a large intracellular burst of metabolic acid production . Despite the excess acid generation, cytosolic pH (pHi) remains near neutrality due to the concomitant stimulation of several homeostatic H+ extrusion mechanisms including a recently described H(+)-conductive pathway . Activation of the conductance by phorbol esters is defective in neutrophils of chronic granulomatous disease (CGD) patients lacking the transmembrane cytochrome b subunits of the NADPH oxidase . This finding suggests that the oxidase itself undertakes H+ translocation or that, alternatively, assembly of the oxidase is required to activate a separate H+ conducting entity . To distinguish between these possibilities, the presence of the conductive pathway was assessed in unstimulated normal and CGD cells by manipulating pHi and the transmembrane potential . Using fluorimetric determinations of pHi, a conductive, Zn(2+)-sensitive alkalinization was observed in neutrophils from both normal and cytochrome b-deficient CGD donors . The electrophysiological properties of the conductance were defined in purified blood monocytes using the whole cell configuration of the patch clamp . Depolarizing pulses induced slowly activating outward currents in cells from both normal and cytochrome b-deficient individuals . The elicited currents were potentiated by cytosolic acidification and did not inactivate within the times tested . As in control leukocytes, the reversal potential of tail currents in the CGD cells closely approximated the H+ equilibrium potential and was unaffected by substitution of the major ionic components of the external bathing medium . At all voltages tested, the magnitude of the evoked currents was comparable in normal and CGD cells . The results indicate that, like macrophages and granulocytes, human monocytes display a voltage-gated highly H(+)-selective conductance . More importantly, our findings imply that the conductive pathway is present in cells devoid of cytochrome b . Therefore, the defective activation of the conductive pathway by protein kinase C agonists in CGD cells is not due to the physical absence of the transporter . Instead we propose that the oxidase functions in a regulatory capacity, facilitating the opening of a distinct H+ conductance during cellular stimulation.

Br J Hosp Med, 1994 Nov 2-15, 52(9), 473 - 8
Antibiotic resistance: the current position and the molecular mechanisms involved; Hayward CM et al.; The introduction of antibiotics heralded a new era in the chemotherapy of infectious diseases, but over the ensuing years bacterial evolutionary responses to the selective pressure of antibiotics have resulted in microorganisms resistant to virtually every known antibiotic . The consequences have been very important in clinical practice, as patients infected with a multi-resistant organism suffer increased morbidity and mortality and often require the use of expensive and potentially toxic antibiotic regimens in order to achieve effective, specific treatment.

Bull Tokyo Dent Coll, 1994 Nov, 35(4), 197 - 205
Histo-pathological study of a glass-ionomer/resin (Geristore) restoration system; Nakazawa Y et al.; The purpose of this experiment was to investigate histo-pathologically the pulpal reaction to a glass-ionomer/resin (Geristore) restoration system in human teeth . Black's class I cavities were prepared in 22 human teeth; these were divided into 2 groups, one with the Geristore after cavity was cleaned with 10% NaOCl solution and 3% H2O2 solution (Group G) and the other with the Geristore after the cavity was applied with Mirage-Bond (Group MG) . The treated teeth were observed clinically over 90 days after operation . They were then extracted for histological examination . No unpleasant symptoms were noted . A few pathological changes were observed . No histo-pathological score differences were observed between groups G and MG . The average evaluation score of pathological results in both groups G and MG were excellent . Microorganisms observed in the cavity dentin of the group G was fewer than in group MG . In some cases, microorganisms were observed along the dentin walls . In conclusion, the pulpal injury due to this Geristore restoration system was slight, and the system was considered to be safe for the pulp and clinically useful.

Appl Environ Microbiol, 1994 Nov, 60(11), 3903 - 8
Engineering of Escherichia coli central metabolism for aromatic metabolite production with near theoretical yield; Patnaik R et al.; Escherichia coli and many other microorganisms synthesize aromatic amino acids through the condensation reaction between phosphoenolpyruvate (PEP) and erythrose 4-phosphate to form 3-deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) . It has been shown that overexpression of transketolase increases the production of DAHP in an aroB mutant strain (unable to further metabolize DAHP) with elevated DAHP synthase . However, the yield (percent conversion) of DAHP from glucose is still low . Stoichiometric analysis shows that many enzymes compete for intracellular PEP . In particular, the phosphotransferase system, responsible for glucose transport in E . coli, uses PEP as a phosphate donor and converts it to pyruvate, which is less likely to recycle back to PEP . This stoichiometric limitation greatly reduces the yield of aromatic metabolites . To relieve this limitation, we overexpressed PEP synthase in the presence of glucose and showed that it increased the final concentration and the yield of DAHP by almost twofold, to a near theoretical maximum . The PEP synthase effect is not observed without overproduced transketolase, suggesting that erythrose 4-phosphate is the first limiting metabolite . This result demonstrates the utility of pathway analysis and the limitation of central metabolites in the high-level overproduction of desired metabolites.

FEMS Microbiol Lett, 1994 Nov 1, 123(3), 225 - 32
New insights into the genetic instability of streptomyces; Leblond P et al.; The high level of genetic instability in Streptomyces ambofaciens is related to large scale DNA rearrangements (deletions and DNA amplifications) which occur within a 2 Mb chromosomal region . The genome of several Streptomyces species is linear and the unstable region is present at the chromosomal extremities . This has raised the questions of the role of the unstable region (which is dispensable under laboratory conditions), the functions of the genes present in this area, and the relationships between instability and chromosomal linearity . The unstable region of Streptomyces and the replication termini of several other microorganisms, including Escherichia coli, share numerous common traits . This suggests that the unstable region of Streptomyces includes the replication terminus, and that chromosomal instability is related to the termination process.

AJR Am J Roentgenol, 1994 Nov, 163(5), 1141 - 5
Treatment of pelvic abscesses and other fluid collections: efficacy of transvaginal sonographically guided aspiration and drainage; Feld R et al.; OBJECTIVE . The purpose of this study was to evaluate the clinical efficacy of transvaginal sonographically guided aspiration and drainage of pelvic fluid collections . MATERIALS AND METHODS . Forty patients underwent transvaginal sonographically guided aspiration of a possible pelvic abscess (41 pelvic collections) . In patients with clinical findings highly suggestive of infection, both purulent and nonpurulent collections were immediately drained via a catheter . In patients with clinical findings moderately suggestive of infection, nonpurulent collections were completely removed by aspiration and the aspirates were cultured; however, purulent collections were immediately drained via a catheter . RESULTS . All collections were successfully accessed by transvaginal sonography . For 27 of the 41 collections, the aspirate was purulent (18 collections) or the patient's clinical findings were highly suggestive of infection (nine collections) and catheter drainage was performed . Seventeen of the 27 collections completely resolved and surgery was not required . Four of the 27 collections were in patients who had surgery for reasons other than persistent infected collection . For six of the 27 collections, catheter treatment was not successful and surgery was required . The overall success rate of catheter drainage was 78% . In the remaining 14 of the 41 collections, the aspirate was serous or serosanguineous, and the patient's clinical findings were moderately suggestive of infection . Cultures of aspirates of seven collections were positive for microorganisms . Eleven collections were successfully treated with antibiotics or no therapy was required (based on culture results); for three, surgery was required . Two complications occurred: one vaginal fistula after catheter drainage and one disruption of vaginal sutures after aspiration . CONCLUSION . Transvaginal sonographically guided drainage is effective treatment of pelvic abscess, being either completely curative or temporizing in 78% of patients . Catheter treatment was unsuccessful and surgery was necessary in 22% of patients . For nonpurulent collections, catheter drainage is indicated only when clinical findings are highly suggestive of infection.

J Lab Clin Med, 1994 Nov, 124(5), 652 - 9
Small intestinal HIV-associated enteropathy: evidence for panintestinal enterocyte dysfunction; Carlson S et al.; To characterize the absorptive defect of AIDS enteropathy, we have used a D-xylose kinetic model of proximal absorption and correlated these findings with Schilling's test for cobalamin absorption, measurements of distal intestinal function . In addition, we compared findings between duodenal and jejunal biopsy and aspirations to determine whether additional information can be obtained by sampling the more distal site . Twelve consecutive patients with AIDS who had 3 to 14 loose bowel movements per day and two stool study results negative for pathogens, were admitted for study . D-xylose testing with oral and intravenous doses was used to determine the rate constants for D-xylose absorption, Ka, and the rate constant for nonabsorptive loss, Ko . Duodenal and distal duodenal-jejunal endoscopic aspirations and biopsies were also performed . Minimal histologic abnormalities were seen in either the proximal or distal biopsy sites . There were no significant differences in mucosal blunting, abnormalities of the enterocytes, lamina propria infiltrate, or presence of microorganisms between duodenal and distal duodenal-jejunal sites . Seventy-five percent had no identifiable pathogens . Ten of 12 patients had diminished Ka, elevated Ko, or both . Two patients had a normal Ka and Ko . Eight of 10 had an abnormal Schilling's test result . Percentage weight loss correlated negatively with Ka (r = 0.75; p = 0.013) and with Schilling's test results (r = 0.65; p = 0.043 . Ka correlated positively with Schilling's test results (r = 0.82; p = 0.004).(ABSTRACT TRUNCATED AT 250 WORDS)

Clin Exp Immunol, 1994 Nov, 98(2), 229 - 33
Heat shock proteins as carrier molecules: in vivo helper effect mediated by Escherichia coli GroEL and DnaK proteins requires cross-linking with antigen; Barrios C et al.; In the past few years we have shown that mycobacterial heat shock proteins (hsp) of 65 and 70 kD exert a very strong helper effect in mice and monkeys when conjugated to peptides and oligosaccharides and given in the absence of adjuvants . In the present study we show that this adjuvant-free helper effect (i) is not due to lipopolysaccharide (LPS), since it was observed in LPS-resistant mice (C3H/HeJ) immunized with hsp-based constructs containing the malaria peptide (NANP)40, and (ii) is characteristic of hsp, since it was not observed with conjugates containing the mycobacterial p38 antigen, which is not a stress protein . Interestingly, the hsp GroEL and DnaK of Escherichia coli, which share a high degree of homology with the mycobacterial 65-kD and 70-kD hsp, respectively, exhibit a strong in vivo helper effect when conjugated to the (NANP)40 peptide, and the conjugates given in the absence of adjuvants . This in vivo helper behaviour of the GroEL and DnaK proteins corresponds well to that observed with the mycobacterial 65-kD and 70-kD hsp, respectively, since the hsp65- and GroEL-based constructs require previous priming of the animals with live bacille Calmette-Guerin (BCG), which is not needed for the hsp70- and DnaK-based constructs . Finally, using both mycobacterial and E . coli hsp we show that their in vivo helper effect in the absence of adjuvants requires cross-linking to the synthetic peptide . Taken together, our results suggest that the adjuvant-free helper effect observed with mycobacterial and E . coli hsp may be a generalized phenomenon, exhibited by hsp from diverse microorganisms . These findings may find applications in the design of vaccine constructs.

Fertil Steril, 1994 Nov, 62(5), 1077 - 9
Hypothalamic-pituitary deficiency after Weil's syndrome: a case report; Panidis D et al.; A case of male hypogonadism after Weil's syndrome is described . Hypogonadism was the result of complete hypothalamic-pituitary deficiency . The relationship between leptospirosis and the endocrinopathy, the incidence that leptospira attacks hypothalamic-pituitary axis, and the mechanism with which the microorganism may cause damage to the pituitary and/or the hypothalamus are discussed.

Mol Microbiol, 1994 Nov, 14(4), 809 - 22
Altered intracellular targeting properties associated with mutations in the Legionella pneumophila dotA gene; Berger KH et al.; Legionella pneumophila dot mutations cause defects in intracellular targeting of the microorganism within cultured macrophages . Each of the previously characterized dot mutations was shown to be complemented by a single open reading frame designated dotA . The defects caused by the mutations appear to be due to disrupted function of the predicted 1048-amino-acid residue DotA protein, and not by polarity effects on a downstream gene . Complementation studies indicated that the product of the dotA53 mutation results in a partially functional DotA protein, consistent with a stable N-terminal fragment having biological activity.

Fetal Diagn Ther, 1994 Nov-Dec, 9(6), 357 - 61
Screening of fetal stem cells for infection and cytogenetic abnormalities; Ek S et al.; Fetal stem cell transplantation may rely on material from therapeutic abortions . It is essential that the stem cell transplant does not transmit any microorganisms that may affect the fetus and that genetically abnormal cells are avoided . To evaluate such contamination, human fetal stem cells collected February 1992 - December 1993 were analyzed for bacterial and fungal growth, and the placentas were karyotyped . Four samples of 70 were positive for different pathogens . Serological screening of 43 women during this period resulted in five seroconversions and revealed one carrier of anti-HCV . Karyotyping revealed two abnormal findings out of 72 samples . Thus, the concept of using material from therapeutic abortions is safe.

Pediatr Res, 1994 Nov, 36(5), 567 - 71
Search for highly conserved viral and bacterial nucleic acid sequences corresponding to an etiologic agent of Kawasaki disease; Rowley AH et al.; The use of conventional methods to detect a possible infectious cause of Kawasaki disease (KD) has been unsuccessful . Using the polymerase chain reaction and DNA hybridization techniques, we have sought evidence that a known or new herpesvirus, parvovirus, or bacterial pathogen is related etiologically to KD . Peripheral blood DNA from acute KD patients was subjected to amplification and dot-blot hybridization to detect the presence of herpesvirus DNA, and acute KD peripheral blood and serum DNA were subjected to dot-blot hybridization for the presence of parvoviral DNA . All samples were negative for both herpesvirus and parvovirus DNA . In addition, we analyzed buffy-coat white blood cell DNA, synovial fluid DNA, and frozen autopsy and formalin-fixed, paraffin-embedded myocardial tissue DNA from KD patients for the presence of highly conserved bacterial 16S ribosomal RNA gene sequences with the polymerase chain reaction, and all were negative . These results argue against a direct pathogenic role for herpesviruses, parvoviruses, and bacteria in KD . This approach to the detection of highly conserved genomic sequences among broad groups of microorganisms can be adapted for the detection of other groups of microorganisms and may yet prove useful in the search for an etiologic agent of KD.

Diagn Microbiol Infect Dis, 1994 Nov, 20(3), 121 - 5
Subcultures of BACTEC-positive but gram or acridine orange stain-negative NR 6A and 7A blood culture bottles are unnecessary; Harrell LJ et al.; A prospective study was done to assess the comparative use of acridine orange and Gram stains for detecting false-positive BACTEC blood culture bottles, thereby eliminating unnecessary subcultures . A total of 1049 NR 6A and 7A bottles that were instrument-positive in the BACTEC 660 nonradiometric system, but were Gram stain-negative, had aerobic and anaerobic subcultures as well as an acridine orange stain performed . Only five of 1049 (0.5%) instrument-positive, Gram stain-negative bottles grew microorganisms on subculture . Of these five microorganisms, acridine orange stain detected two . All five microorganisms were assessed not to be clinically significant based on review of the patients' charts . Our data showed that the Gram stain and the acridine orange stain are comparable for detecting false-positive NR 6A and 7A bottles . We conclude that subculture of BACTEC-positive, Gram stain-negative NR 6A and 7A bottles is not necessary.

Curr Genet, 1994 Nov-Dec, 26(5-6), 390 - 7
Stabilization of methionine-rich protein in Saccharomyces cerevisiae: targeting of BZN protein into the peroxisome; Nicaud JM et al.; We have constructed a gene coding for the 12-kDa intermediate form of the 2s methionine-rich protein from Bertholletia excelsa seeds . This protein, expressed intracellularly in yeast, is characterised by a 20-min half-life . By adding 11 amino acids corresponding to the peroxisome-targeting sequence (PTSc) of luciferase, we have significantly increased its half-life . This stabilization allowed accumulation of the BZN protein into the peroxisome as judged by cell fractionation . Accumulation of the 12-kDa protein results in a significant increase of the total methionine content in yeast cells (30%) indicating that such a microorganism could represent a practicable protected shuttle for an animal-feed additive.

Int J Food Microbiol, 1994 Nov, 23(3-4), 265 - 75
Modelling the growth, survival and death of microorganisms in foods: the UK food micromodel approach; McClure PJ et al.; Techniques for the development of mathematical models in the area of predictive microbiology have greatly improved recently, allowing better and more accurate descriptions of microbial responses to particular environmental conditions, thus enabling predictions of those responses to be made with greater confidence . Recognising the potential value of applying these techniques in the food industry, the Ministry of Agriculture, Fisheries and Food (MAFF) initiated a nationally coordinated five-year programme of research into the growth and survival of microorganisms in foods, with the aim of developing a computerised Predictive Microbiology Database in the UK . This initiative has resulted in the systematic generation of data, through protocols which ensure consistency of methodology, so that data in the database are truly comparable and compatible, and lead to reliable predictive models . The approaches taken by scientists involved in this programme are described and the various stages in the development of mathematical models summarized . It is hoped that this initiative and others being developed in the USA, Australia, Canada and other countries, will encourage a more integrated approach to food safety which will influence all stages of food production and, eventually, result in the development of an International Predictive Microbiology Database.

Int J Food Microbiol, 1994 Nov, 23(3-4), 241 - 64
Predictive microbiology; Ross T et al.; Predictive microbiology is based upon the premise that the responses of populations of microorganisms to environmental factors are reproducible, and that by considering environments in terms of identifiable dominating constraints it is possible, from past observations, to predict the responses of those microorganisms . Proponents claim that predictive microbiology offers many benefits to the practice of food microbiology, and there is growing interest internationally . This review considers the origins, benefits and approaches to predictive microbiology and critically considers limitations and potential solutions . It is suggested that the traditional delineation between kinetic and probabilistic models is artificial, and that the two approaches represent the opposite ends of a spectrum of modelling needs . It is concluded: that despite the complexity of many food systems predictive modelling can be successfully applied; that strategies based on predictive models can simplify problems and allow useful predictions and analyses to be made; that the full potential of the technique has not yet been realised; and that "predictive microbiology" may be seen as providing a rational framework for understanding the microbial ecology of food.

J Periodontol, 1994 Nov, 65(11), 996 - 1001
Smoking as an additional risk for tooth loss; Holm G; Epidemiological studies have shown that loss of teeth is associated with increasing age . This was explained as the result of the action of microorganisms which, as components of dental plaque, destroyed the tooth by causing caries or periodontitis . Routine prevention programs therefore concentrated on removal of plaque, resulting in good oral hygiene . Despite good oral hygiene some individuals developed periodontitis . Studies have indicated that smoking may be a risk factor for this disease . This study was undertaken to determine whether or not smoking is also a risk factor for tooth loss . A total of 273 individuals were followed for 10 years, during which 93 individuals lost a total of 260 teeth . Younger individuals and especially males smoking more than 15 cigarettes a day were found to have the highest relative risk of losing teeth (4.55 and 3.18 respectively) . In the younger age groups the proportional attributable risk was also highest; 78% for smokers smoking more than 15 cigarettes a day . The combination of a high plaque score and smoking was, together with age, the strongest predictor of tooth loss . The findings of this study suggest that smokers, especially those in the age group < 50 years, are a high risk group for tooth loss.

Infect Control Hosp Epidemiol, 1994 Nov, 15(11), 724 - 33
Glutaraldehyde: current status and uses; Russell AD; Glutaraldehyde (pentanedial) is a dialdehyde that displays potent bactericidal, fungicidal, mycobactericidal, sporicidal, and virucidal activity . Pertinent to its activity is its interaction with amino groups in proteins and enzymes, but this simplistic statement masks the manner in which it inactivates various types of microorganisms . Notwithstanding its toxicity for medical staff, glutaraldehyde remains an invaluable compound for high-level disinfection purposes in endoscopy units.

Ann Gastroenterol Hepatol (Paris), 1994 Nov-Dec, 30(6), 270 - 6, 281; discussion 281-2
{Absorption, distribution and excretion of vitamin B12}; Nicolas JP et al.; During our first communication {1}, 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.

Oral Surg Oral Med Oral Pathol, 1994 Nov, 78(5), 634 - 45
Microbiologic factors in endodontology; Seltzer S et al.; The role of microorganisms in the cause of endodontic lesions has been intensively investigated . Bacterial components such as endotoxin and other cell wall components are implicated in the development of pulpal and periapical inflammation . Newer anaerobic microbiologic techniques have facilitated accurate and reproducible identification of endodontic pathogens, some of which have been reclassified . This article reviews and correlates newer microbiologic findings with clinical symptoms.

Appl Biochem Biotechnol, 1994 Nov, 49(2), 93 - 9
Effect of sodium dodecyl sulfate on lipase of Candida lipolytica; Nascimento AE et al.; The effects of sodium dodecyl sulfate on extracellular lipase produced by Candida lipolytica have been studied . The microorganism was grown in culture medium containing different sodium dodecyl sulfate concentrations added to the culture at different intervals of growth . The extracellular lipase activity was not detected when the treated culture supernatants were directly tested in Yeast Mold Agar-Triolein-Rhodamine plates, regardless of surfactant addition time and concentrations . However, after ammonium sulfate precipitation and dialysis, the extracellular lipase activity could be recovered . Therefore, the surfactant, under the experimental conditions used here, does not seem to be able to inhibit lipase production, but it does inhibit the enzyme activity because of its presence in the mixture of the reaction.

Minerva Med, 1994 Nov, 85(11), 563 - 8
Efficacy comparison of glutaraldehyde-phenate vs other glutaraldehydes in fomites disinfection, by different methods; Herruzo-Cabrera R et al.; OBJECTIVE . To compare the efficacy of glutaraldehyde-phenate against four other glutaraldehydes . DESIGN . We use two methods: (1) Bacteriostatic method- With 97 microrganisms of 8 different species . (2) Bactericide method- With a low contamination (10(4)cfu) plus organic soil (simulating the work conditions of glutaraldehyde when we wash fomites before disinfection), we used six microorganisms (the most sensitive and the most resistant, according to the first method, of three species: P . aeruginosa, R . pneumoniae and S . aureus) in different times and concentrations . RESULTS . Glutaraldehyde-phenate is the most active against Gram-positives, but less with Gram-negatives . However when we study the total effect of the five glutaraldehydes, there are no significant differences among the mean of the minimum inhibitory concentrations (MICm) . With the bactericide method the total bactericide effect (0% survival) is easily achieved with the five glutaraldehydes at 2% dilution, but when we reduced the concentration (1/16) we needed 60 minutes for glutaraldehyde-phenate and 15-30 minutes with the rest . CONCLUSIONS . The five products have got a similar efficacy in higher concentration, but at 1/16 dilution glutaraldehyde-phenate need increase the contact-time on the fomite.

Biol Signals, 1994 Nov-Dec, 3(6), 271 - 7
Effects of insulin and glucose tolerance factor on glucose uptake by yeast cells; Mirsky N et al.; Addition of mammalian insulin or glucose tolerance factor (GTF), to Saccharomyces cerevisiae ATCC 7752, increased 2-deoxyglucose uptake by yeast cells . The enhancement was dose-dependent, and also dependent on preincubation of the cells with glucose, prior to the addition of the hormone . The effect of insulin on glucose uptake by the yeast was very similar to the effect of GTF on these cells . Insulin and GTF increased also the growth of yeast cells, while denatured insulin or glucagon failed to act . Our findings support the view that both insulin and GTF might regulate carbohydrate metabolism in microorganisms.

Nat Struct Biol, 1994 Nov, 1(11), 789 - 94
Human mannose-binding protein carbohydrate recognition domain trimerizes through a triple alpha-helical coiled-coil; Sheriff S et al.; Human mannose-binding protein is a hexamer of trimers with each subunit consisting of an amino-terminal region rich in cysteine, 19 collagen repeats, a 'neck', and a carbohydrate recognition domain that requires calcium to bind ligand . A 148-residue peptide, consisting of the 'neck' and carbohydrate recognition domains forms trimers in solution and in crystals . The structure of this trimeric peptide has been determined in two different crystal forms . The 'neck' forms a triple alpha-helical coiled-coil . Each alpha-helix interacts with a neighbouring carbohydrate recognition domain . The spatial arrangement of the carbohydrate recognition domains suggest how MBP trimers form the basic recognition unit for branched oligosaccharides on microorganisms.

Vet Microbiol, 1994 Nov, 42(2-3), 147 - 58
Analysis of the variability in expression of Mycoplasma gallisepticum surface antigens; Garcia M et al.; The in vitro expression of surface epitopes for different strains of Mycoplasma gallisepticum (MG) was studied with a panel of monoclonal antibodies (mAbs) using indirect colony immunostaining and Western blot (WB) analyses . Immunostaining of colonies with mAbs showed that five epitopes had different degrees of variable expression, while one epitope was permanently expressed in vitro . Colonies that failed to express the studied epitopes had the potential of phenotypically switching the expression of these epitopes in vitro . Variable and permanently expressed epitopes were associated with more than one protein and not all mAb-defined proteins were responsible for the immunostaining of intact MG colonies . The ability of MG to variably express their surface epitopes maybe the mechanism utilized by the microorganism to avoid the host immune response.

Nippon Rinsho, 1994 Nov, 52(11), 2799 - 804
{T cell development and selection in extrathymic environments}; Kubota H et al.; Thymocytes express randomly diversified TCRs by TCR gene rearrangement and those reactive to self antigens are negatively selected while those capable of recognizing antigens in the context of self MHC antigens are positively selected . The selection process in the thymus for forming the TCR repertoire is a basic rule for the formation of T cell repertoire . Recently, however, certain T cells have been reported to be generated extra-thymically and exhibit the restricted TCR repertoire . Some of these T cells are suggested to recognize self antigens in a non-MHC-restricted fashion . Those self antigens, such as endogenous retrovirus, surface activation antigens, and bacterial antigens, are induced by exogenous stress, transformation and invading microorganisms . T cells which recognize such self antigens seem to be activated and expand clonally whenever the antigens are expressed in the periphery . Although the biological roles of the unique T cells remain obscure, it is suggested that they may participate in immune surveillance system to monitor cell integrity and to destroy cells altered by transformation and infection by microorganisms.

Mutat Res, 1994 Nov, 315(3), 213 - 28
High-level expression of the photorepair gene in Drosophila ovary and its evolutionary implications; Todo T et al.; DNA photolyase catalyzes light-dependent repair of cis, syn-cyclobutane dipyrimidines (pyrimidine dimers); its apoenzyme is encoded by the photorepair (phr) gene . The phr cDNA was cloned from D . melanogaster; it has an open reading frame to encode a 61,483-Da protein . The phr cDNA hybridized to band 44C-D of Drosophila polytene chromosome, equivalent to the locus of the phr- gene . Drosophila photolyase is made of an apoenzyme with a molecular weight of 62 kDa . Drosophila photolyase is extraordinarily abundant in the embryo and adult ovary, whereas mRNA of the phr gene is abundant only in the ovary . The action spectrum of Drosophila photolyase for photoreactivation has a maximum at 440 nm . The phr gene of Drosophila has about 60% identical amino acid sites with that of goldfish but only 13-18% with those of microorganisms . Implications of the unique characteristics of the Drosophila phr gene are discussed overviewing the diversified characteristics of phr genes in various organisms that have presumably evolved from a common ancestral gene.

Eur J Immunol, 1994 Nov, 24(11), 2850 - 4
Deficient expression of co-stimulatory molecules on Leishmania-infected macrophages; Kaye PM et al.; Co-stimulatory signals are necessary for the full activation of T cells for growth and effector function . As co-stimulatory molecules are normally regulated in their expression, it has been suggested that microorganisms enhance their expression on host antigen-presenting cells (APC), thus allowing efficient generation of anti-microbial immunity . We here describe experiments which demonstrate that infection of macrophages, both in vitro and in vivo, by the protozoan parasite Leishmania donovani fails to trigger expression of co-stimulatory molecules B7-1 and heat-stable antigen on these APC . Furthermore, infection with this parasite inhibits the macrophage response to normal regulatory signals, such as bacterial lipopolysaccharide . These changes in the cell surface are mirrored in functional studies of co-stimulation in vitro . Together, these data suggest a further facet of parasite interference in host immunity, but also indicate a potential new target for immunotherapy.

Infect Immun, 1994 Nov, 62(11), 4900 - 8
Chlamydia trachomatis serovar L2 induces protein tyrosine phosphorylation during uptake by HeLa cells; Birkelund S et al.; Chlamydia trachomatis L2 is an obligate intracellular microorganism with a unique biphasic life cycle . The extracellular form, the elementary body (EB), is infectious but metabolically inactive . Attachment of EBs to host cells is medicated by a heparan sulfate-like glycosaminoglycan . Following attachment, the EB is internalized within a membrane-bound vesicle, and during the first 8 h of infection the vesicles are transported to a perinuclear location where they aggregate and fuse . By use of a monoclonal antibody against phosphotyrosine, we showed that three classes of proteins are tyrosine phosphorylated: a triple band of 68, 66, and 64 kDa, a 97-kDa band, and a 140-kDa band . The phosphorylation could be detected by immunoblotting from 15 min after infection of HeLa cells . We followed the movement of the EBs and the tyrosine phosphorylation of proteins by double-labelling immunofluorescence microscopy with the same monoclonal anti-phosphotyrosine antibody and a polyclonal antibody against the C . trachomatis L2 outer membrane complex . During the first 8 h of infection, the phosphorylation colocalized with EBs . Sixteen hours after infection, EBs have reorganized to the replicating reticulate bodies, forming an inclusion . At this time, phosphorylation was seen as dotted spots in the periphery of the inclusion.

Schweiz Med Wochenschr, 1994 Oct 22, 124(42), 1852 - 61
{Diarrhea due to rare forms of colitis: microscopic (lymphocytic, collagenous) colitis and spirochetosis}; Gebbers JO et al.; Lymphocytic and collagenous colitis, uncommon entities that are identifiable by histopathologic examination only, and intestinal spirochetosis may cause chronic diarrhea . Data on incidence, histopathology, and diseases associated with these infrequent forms of colitis are reviewed . Etiology and pathogenesis of lymphocytic and collagenous colitis are still unknown, but immuno-inflammatory factors may be involved in both forms as well as, in collagenous colitis, primary disorders of collagen metabolism or drug-induced toxic effects . The significance of intestinal colonization by spirochetes is disputed; however, recent results indicate that these microorganisms are capable of inducing disease.

J Immunol, 1994 Oct 15, 153(8), 3791 - 803
Characterization and affinity isolation of xenoreactive human natural antibodies; Parker W et al.; Natural Abs, which are thought to provide an initial defense against invasive microorganisms, include isohemagglutinins, anti-phosphatidylcholine Abs, and anti-alpha-galactose Abs . We have evaluated the physiologic properties of the fraction of human natural Abs that bind to porcine endothelial cells and that would, as a result, initiate the rejection of a porcine organ transplanted into a human . The concentration of xenoreactive IgM in the serum varied widely in the population (5 to 105 micrograms/ml), but was highly dependent on the concentration of IgM in the serum (r = 0.85) . Despite this variation and the potential diversity of epitopes recognized, human xenoreactive natural Abs exhibited surprisingly homogeneous binding characteristics, both in one individual and in the population . The apparent avidity determined by using a direct ELISA yielded a functional dissociation constant of 10(-8) M to 10(-10) M, depending on the temperature used . This high functional Kd apparently results from polyvalent interactions between the IgM and the porcine cell surface . Although the xenoreactive IgMs were absorbed by structurally diverse molecules such as ssDNA and thyroglobulin, about 80% of the xenoreactive Abs were specific for the terminal alpha-galactose determinant . A method was developed for affinity isolation of xenoreactive natural Abs by using a thermal extraction procedure . The method quantitatively accounts for all xenoreactive IgM, yielding functional IgM as evidenced by Ag binding and complement activation . Given the overlapping specificity of xenoreactive Abs in the population and the homogeneity of the functional Kd, the natural humoral immunologic barrier to xenotransplantation may be far less formidable than previously thought.

Sci Total Environ, 1994 Oct 14, 155(2), 125 - 30
Fungal metabolite extracts active against phytopathogens; Okeke B et al.; The effectiveness of some genetically engineered microorganisms in the control of plant disease pathogens is widely acknowledged . These biopesticides, so far, pose less danger to the environment . However, little attention has been paid to the potential benefit of the use of exometabolites of some microorganisms in spite of their known activity and high biodegradability . A total of 1108 fungal metabolite extracts obtained from different strains of micromycetes cultured in two different liquid media (malt extract and yeast saccharose) were tested for antifungal activity . The target organisms were Collectotrichum musae, Drechslera spicifera, Fusarium oxysporum, Geotrichum candidum, Pyricularia oryzae, Drechslera oryzae and Gerlachia oryzae . Percentage mycelial growth inhibition activities varied widely with the different taxonomic groups . Extracts from Aspergillus and Penicillium spp . consistently showed the highest activity . A greater number of micromycetes produced active extracts in a liquid yeast extract saccharose medium than in a liquid malt extract medium . Mycelial growth inhibition diameters were also greater in assays with extracts from the yeast extract saccharose medium . The results generally demonstrated fungal metabolite extracts as potential sources of agricultural chemical input.

Proc Natl Acad Sci U S A, 1994 Oct 11, 91(21), 10000 - 4
Unusual mechanism of hydrocarbon formation in the housefly: cytochrome P450 converts aldehyde to the sex pheromone component (Z)-9-tricosene and CO2; Reed JR et al.; An unusual mechanism for hydrocarbon biosynthesis is proposed from work examining the formation of (Z)-9-tricosene (Z9-23:Hy), the major sex pheromone component of the female housefly, Musca domestica . Incubation of (Z)-15-{1-14C}- and (Z)-15-{15,16-3H2}tetracosenoic acid (24:1 fatty acid) with microsomes from houseflies gave equal amounts of {3H}Z9-23:Hy and 14CO2 . The formation of CO2 and not CO, as reported for hydrocarbon formation in plants, animals, and microorganisms {Dennis, M . & Kolattukudy, P . E . (1992) Proc . Natl . Acad . Sci . USA 89, 5306-5310}, was verified by trapping agents and by radio-GLC analysis . Incubation of (Z)-15-{15,16-3H2}tetracosenoyl-CoA with microsomal preparations in the presence of NADPH and O2 gave almost equal amounts of (Z)-15-3H2}tetrasosenal (24:1 aldehyde) and Z9-23:Hy . Addition of increasing amounts of hydroxylamine (aldehyde trapping agent) caused a decrease in hydrocarbon formation with a concomitant increase in oxime (aldehyde derivative) formation . The 24:1 aldehyde was efficiently converted to (Z)-9-tricosene only in the presence of both NADPH and O2 . Bubbling carbon monoxide (20:80 CO/O2) or including an antibody against housefly cytochrome P450 reductase inhibited the formation Z9-23:Hy from 24:1 aldehyde . These data demonstrate an unusual mechanism for hydrocarbon formation in insects in which the acyl-CoA is reduced to the corresponding aldehyde and then carbon-1 is removed as CO2 . The requirement for NADPH and O2 and the inhibition by CO and the antibody to cytochrome P450 reductase strongly implicate the participation of a cytochrome P450 in this reaction.

Ugeskr Laeger, 1994 Oct 3, 156(40), 5862 - 5
{Cheese-packers' disease--respiratory complaints at a cheese-packing dairy}; Dahl S et al.; Twenty-one present and three former employees working in the paching room of a cheese-making dairy underwent clinical examinations including symptom history, smoking habits, chest examination, and pulmonary function tests . Blood samples were drawn to determine level of peripheral eosinophil count and antibodies to microorganisms detected by air samples . Air sample concentrations of Penicillium camemberti var . candidum, used in the cheese-production, were very high (> 6000 colony forming units per cubic metre of air) . In 15 of the 24 exposed workers, precipitating antibodies towards this fungus were detected, but no antibodies were detected in a reference consisting of pooled blood from 1000 donors . Of the sixteen workers with airway symptoms five had asthma requiring treatment . Two-thirds of the symptomatic cheeseworkers but only half of those without symptoms had precipitating antibodies . The high frequency of precipitating antibodies together with the clinical causes of the airway symptoms indicates an aetiological relationship between airway symptoms and heavy exposure to Penicillium camemberti.

Occup Environ Med, 1994 Oct, 51(10), 683 - 8
Effect of air humidification on the sick building syndrome and perceived indoor air quality in hospitals: a four month longitudinal study; Nordstrom K et al.; The sensation of dryness and irritation is essential in the sick building syndrome (SBS), and such symptoms are common in both office and hospital employees . In Scandinavia, the indoor relative humidity in well ventilated buildings is usually in the range 10-35% in winter . The aim of this study was to evaluate the effect of steam air humidification on SBS and perceived air quality during the heating season . The study base consisted of a dynamic population of 104 hospital employees, working in four new and well ventilated geriatric hospital units in southern Sweden . Air humidification raised the relative air humidity to 40-45% in two units during a four months period, whereas the other two units served as controls with relative humidity from 25-35% . Symptoms and perceived indoor air quality were measured before and after the study period by a standardised self administered questionnaire . The technical measurements comprised room temperature, air humidity, static electricity, exhaust air flow, aerosols, microorganisms, and volatile organic compounds in the air . The most pronounced effect of the humidification was a significant decrease of the sensation of air dryness, static electricity, and airway symptoms . After four months of air humidification during the heating season, 24% reported a weekly sensation of dryness in humidified units, compared with 73% in controls . No significant changes in symptoms of SBS or perceived air quality over time were found in the control group . The room temperature in all units was between 21-23 degrees C, and no significant effect of air humidification on the air concentration of aerosols or volatile organic compounds was found . No growth of microorganisms was found in the supply air ducts, and no legionella bacteria were found in the supply water of the humidifier . Air humidification, however, significantly reduced the measured personal exposure to static electricity . It is concluded that air humidification during the heating season in colder climates can decrease symptoms of SBS and perception of dry air.

Appl Biochem Biotechnol, 1994 Oct, 49(1), 59 - 74
Lipase from a Brazilian strain of Penicillium citrinum; Pimentel MC et al.; A lipases (glycerol ester hydrolases E . C . 3.1.1.3) from a brazilian strain of Penicillium citrinum has been investigated . When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL) . In addition, decrease of yeast extract concentration also reduces the lipase activity . Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected . Purification by precipitation with ammonium sulfate showed best activity in the 40-60% fraction . The optimum temperature for enzyme activity was found in the range of 34-37 degrees C . However, after 30 min at 60 degrees C, the enzyme was completely inactivated . The enzyme showed optimum at pH 8.0 . The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28 degrees C) for 8 mo . This result in lipase stability suggests an application of lipases from P . citrinum in detergents and other products that require a high stability at room temperature.

Bioessays, 1994 Oct, 16(10), 715 - 7
Microbial adaptation to a changeable environment: cell-cell interactions mediate physiological and genetic differentiation; Rosenzweig RF et al.; Recent work by Magnuson, Solomon and Grossman(1) adds to a growing body of evidence indicating that microorganisms possess sophisticated signaling systems that enable them to sense and respond to environmental challenges . Typically, this response results in morphological, physiological and even genetic differentiation, paralleling that observed among higher organisms . These signaling systems may be interpreted as adaptations that maximize the reproductive potential of a population.

Oftalmologia, 1994 Oct-Dec, 38(4), 363 - 5
{The etiopathogenesis of uveitis}; Denislam D; A review of the different etiopathological classification of uveitis is presented . In our present stage of knowledge an exhaustive classification is almost impossible . This is due to the fact that any microorganism foreign body or pathological process which can produce a general inflammation is able to cause an uveitis.

FEMS Microbiol Rev, 1994 Oct, 15(2-3), 261 - 77
Biochemical diversity among sulfur-dependent, hyperthermophilic microorganisms; Adams MW; Hyperthermophiles are a recently discovered group of microorganisms that grow at and above 90 degrees C . They currently comprise over 20 different genera, and except for two novel bacteria, all are classified as Archaea . The majority of these organisms are obligately anaerobic heterotrophs that reduce elemental sulfur (S degree) to H2S . The best studied from a biochemical perspective are the archaeon, Pyrococcus furiosus, and the bacterium, Thermotoga maritima, both of which are saccharolytic . P . furiosus is thought to contain a new type of Entner-Doudoroff pathway for the conversion of carbohydrates ultimately to acetate, H2 and CO2 . The pathway is independent of nicotinamide nucleotides and involves novel types of ferredoxin-linked oxidoreductases, one of which has tungsten, a rarely used element, as a prosthetic group . The only site of energy conservation is at the level of acetyl CoA, which is the presence of ADP and phosphate is converted to acetate and ATP in a single step . In contrast, T . maritima utilizes a conventional Embden-Meyerhof pathway for sugar oxidation . P . furiosus also utilizes peptides as a sole carbon and energy source . Amino acid oxidation is thought to involve glutamate dehydrogenase together with at least three types of novel ferredoxin-linked oxidoreductases which catalyze the oxidation of 2-ketoglutarate, aryl pyruvates and formaldehyde . One of these enzymes also utilizes tungsten . In P . furiosus, virtually all of the reductant that is generated during the catabolism of both carbohydrates and peptides is channeled to a cytoplasmic hydrogenase . This enzyme is now termed sulhydrogenase, as it reduces both protons to H2 and S degrees (or polysulfide) to H2S . S degrees reduction appears to lead to the conservation of energy in P . furiosus but not in T . maritima, although the mechanism by which this occurs is not known.

FEMS Microbiol Rev, 1994 Oct, 15(2-3), 251 - 60
Regulated gene expression in methanogens; Eggen RI; Methanogens form a very large and diverse group of microorganisms within the domain of the Archaea . Energy for their growth is obtained by the reduction of a variety of substrates into methane . Several genes, coding for enzymes involved in methanogenesis or in the central metabolism have been cloned and studied . The molecular features of their expression signals have been compared with bacterial and eukaryal expression signals . This indicated that the transcription process is an intermediate form between the specific processes known in Bacteria and Eukarya . The translation system that is used in Archaea is very similar with the process in Bacteria . Although the molecular features of genes and expression signals in Archaea are well-studied, investigations on the regulation of gene expression in these organisms are very scarce . In order to give insight into molecular regulatory mechanisms in methanogens, the current knowledge of regulated systems in methanogens will be reviewed in this manuscript.

Arch Pathol Lab Med, 1994 Oct, 118(10), 1028 - 30
Sclerosing hemangioma of the lung . Granulomatous variant; Moran CA et al.; We present a case of granulomatous sclerosing hemangioma of the lung in a 43-year-old white woman in whom a pulmonary nodule was found on a routine chest roentgenogram . Surgical resection of a well-circumscribed pulmonary nodule was performed . Histologically, the tumor showed the typical features of sclerosing hemangioma with the unusual feature of a florid granulomatous reaction . Immunohistochemical studies using antibodies for epithelial membrane antigen decorated the tumoral cells, while factor VIII was positive in the vascular structure . Histochemical stains for microorganisms yielded negative results.

Gan To Kagaku Ryoho, 1994 Oct, 21(14), 2525 - 32
{Properties of interleukin 8 and its correlation with inflammatory diseases and malignant neoplasia}; Matsushima K; Inflammation is a vital consequence of tissue injury caused by various reasons including invasion of foreign particles, infection with microorganisms, autoimmune responses, ischemia-reperfusion injury, and malignant neoplasia . In 1987, a major neutrophil chemotactic and activating factor, now called interleukin 8 (IL-8), was purified and molecularly cloned . In this article, general overview of IL-8 was made describing biochemical structure, regulation of production of IL-8, properties of the receptors for IL-8 and pathophysiological roles of IL-8 in inflammation.

J Pediatr, 1994 Oct, 125(4), 541 - 8
Familial enteropathy with villous edema and immunoglobulin G2 subclass deficiency; Smith LJ et al.; We describe a familial form of recurrent acute, life-threatening secretory diarrhea associated with distinctive jejunal histologic changes and IgG2 subclass deficiency . Symptoms begin abruptly with anorexia and vomiting, and progress within hours to massive secretory diarrhea and shock with profound neutropenia and hypoproteinemia, including hypoalbuminemia and hypogammaglobulinemia . Affected survivors recover quickly and thereafter grow and develop normally . Biopsy specimens obtained during remission from 3 adults and 11 children show club-shaped jejunal villi broadened by edema and histiocytes with imbibed fluid; the overlying intestinal epithelium and brush border appear normal, but the basement membrane is interrupted in some areas . No characteristic microorganisms have been identified in association with the syndrome . Clinical manifestations cease in the second decade, but the abnormal jejunal histologic pattern persists into adult life . Female and male patients are equally affected, although all fatal cases have been in female subjects . Inheritance appears dominant with variable penetrance: one family member without a history of diarrhea has characteristic biopsy findings and another appears to be an obligate carrier with normal biopsy findings . Affected individuals have a reduced serum concentration of IgG2 . We believe that this familial enteropathy is a unique entity, not previously described.

J Exp Med, 1994 Oct 1, 180(4), 1523 - 7
A pathway for entry of retroviruses into the host through M cells of the respiratory tract; Morin MJ et al.; Many microorganisms gain access to the systemic circulation after entering the respiratory tract . The precise pathways used to cross the mucosal barriers of the lungs have not been clearly described . We have used the mammalian reoviruses in order to determine the pathway that a systemic virus uses to penetrate the mucosal barrier and enter the systemic circulation after entering the airways of the lungs . Reoviruses enter through pulmonary M cells, which overlie bronchus-associated lymphoid tissue, and subsequently spread to regional lymph nodes . Thus, the pathway through M cells represents a strategy by which viruses and probably other microorganisms can penetrate the mucosal surface of the respiratory tract and thereby enter the systemic circulation.

Infect Immun, 1994 Oct, 62(10), 4650 - 1
Stimulation or inhibition of the respiratory burst in cultured macrophages in a mycobacterium model: initial stimulation is followed by inhibition after phagocytosis; Gordon AH et al.; Microorganisms cause varying degrees of stimulation of superoxide (O2-) production (respiratory burst {RB}) in macrophages but in some cases apparently inhibit the RB induced in the same monolayers by a conventional stimulator . We have explored these differences . A mycobacterium model, the slowly multiplying mouse pathogen Mycobacterium microti, induced a modest RB in resident macrophage monolayers, compared with the substantial RB induced by opsonized zymosan (Zy) . However, if the 1-h M . microti pulse immediately preceded the Zy assay (instead of being concurrent), the RB was consistently less than that elicited by the Zy alone . Cytochalasin (an inhibitor of phagocytosis) enhanced Zy-induced RB, supporting the view that the burst is cell surface mediated, but this agent apparently eliminated the inhibition of the Zy-induced RB caused by prior M . microti exposure, suggesting that this inhibition may have an intracellular origin . The inhibition described extended not only to another mycobacterium (Mycobacterium bovis BCG) but also to a previous application of Zy itself . The general implications for macrophage functions of these observations on timing and sites of initiation are briefly discussed.

Int J Sports Med, 1994 Oct, 15 Suppl 3, S179 - 83
Mucosal (secretory) immune system responses to exercise of varying intensity and during overtraining; Mackinnon LT et al.; Athletes are susceptible to upper respiratory tract infection (URTI) during intense training and after major competition; high rates of URTI have also been associated with the overtraining syndrome (staleness) . Secretory immunoglobulin A (IgA), the predominant immunoglobulin in mucosal secretion, is a major effector of resistance against pathogenic microorganisms causing URTI . Previous work has shown that salivary IgA levels decrease after a single bout of intense prolonged exercise . The purpose of these studies was to examine the IgA response to various exercise conditions . Whole, unstimulated saliva was obtained before and after exercise . IgA concentration (microgram.mg protein-1) was measured by ELISA and IgA secretion rate (microgram.min-1) calculated . Study 1: Recreational joggers ran on a treadmill for 40 min at 55% and 75% VO2peak and competitive distance runners ran for 90 min at the same intensites . In both groups, IgA secretion rate did not change significantly after exercise at either intensity . Study 2: Competitive runners ran on a treadmill for 90 min at 75% VO2peak on 3 consecutive days . IgA secretion rate decreased 20 to 50% after exercise (p < .001) . Post-exercise IgA secretion rates were significantly lower (p < .05) on days 2 and 3 compared with day 1 . Study 3: Elite swimmers were followed over a 6 month season, with IgA concentration measured at 5 times . Throughout the season, IgA concentration was significantly (p < .05) lower in stale compared with well-trained swimmers.(ABSTRACT TRUNCATED AT 250 WORDS)

J Cutan Pathol, 1994 Oct, 21(5), 437 - 45
The spectrum of cutaneous granulomatous vasculitis: histopathologic report of eight cases with clinical correlation; Gibson LE et al.; Cutaneous granulomatous vasculitis is an uncommon histopathologic finding that has been associated with lymphoproliferative disorders, systemic vasculitis, autoimmune inflammatory diseases, and infection . To define further the concept of cutaneous granulomatous vasculitis and to emphasize its clinical importance, we reviewed biopsy material from 8 patients seen from 1985 through 1992 . All biopsies showed evidence of blood vessel damage with fibrinoid change or hemorrhage (or both) and granulomatous inflammation in and around vessel walls . Special stains for microorganisms were negative in all cases . Associated medical disorders included neuropathy (2 patients), sarcoid-like disease (2), systemic vasculitis (1), lymphoma and suspected lymphoma (1 each), and associated herpes simplex virus (1) . T-cell gene-rearrangement studies were negative in a patient with suspected lymphoma . Granulomatous cutaneous vasculitis is most commonly associated with lymphoma and systemic vasculitis . In selected cases, infection should be considered as an underlying cause.

Vet Immunol Immunopathol, 1994 Oct, 43(1-3), 143 - 50
Immunology of the porcine gastrointestinal tract; Stokes CR et al.; The gastrointestinal immune system is presented with a contrasting array of antigens, ranging from harmless dietary components to highly pathogenic microorganisms . The mucosal immune system has the ability to recognise different groups of antigens and has evolved a battery of responses from which an appropriate response may be orchestrated . The question as to how the mucosal immune system categories antigens and selects a particular response is central to this process but it remains largely unanswered . The solution to this question is likely to hold the key to the development of safe and effective mucosal vaccines as well as suggesting methods for the prevention and control of allergic responses . Enteric diseases resulting from antigens (microbial and dietary) presented via the gastrointestinal tract are a major cause of morbidity and mortality . In addition to being of substantial economic importance, growing public awareness on animal welfare and food quality confirms the urgent need for new methods of disease control.

Pharmacol Ther, 1994 Oct, 64(1), 23 - 35
Inhibitors of the insulin receptor tyrosine kinase; Srinivas PR et al.; Insulin is a polypeptide hormone consisting of 51 amino acids . Insulin promotes a variety of anabolic enzymatic pathways and inhibits many catabolic enzymatic pathways involved in energy storage, as well as in synthesis of structural tissue proteins . In addition, insulin serves as a growth factor, modulating mitogenesis, growth and differentiation . Insulin mediates all of its effects by initially binding and activating its specific cell-surface receptor . Conformational changes induced by insulin binding lead to activation of intrinsic receptor tyrosine kinase . Thus, the study of tyrosine kinase inhibitors, whether synthetically produced or purified from microorganisms or humans, has led to elucidation of molecular details of physiological insulin signaling.

Scand J Gastroenterol, 1994 Oct, 29(10), 923 - 9
Mycobacterium paratuberculosis in intestinal tissue from patients with Crohn's disease demonstrated by a nested primer polymerase chain reaction; Lisby G et al.; BACKGROUND: The etiology of Crohn's disease remains unknown, but current research has concentrated on autoimmunity and/or mycobacterial infection . The polymerase chain reaction (PCR) enables the detection of genetic material even when very few microorganisms are present . METHODS: A nested primer PCR for detection of a multi-copy insertional element (IS900) specific for Mycobacterium paratuberculosis was applied to DNA extracted from fresh and from paraffin-embedded intestinal tissue obtained from patients undergoing surgery . RESULTS: In fresh intestinal tissue from 11 of 24 patients with Crohn's disease, from 2 of 10 patients with ulcerative colitis, and from 3 of 28 patients with other colonic disorders, specific M . paratuberculosis DNA was found . In paraffin-embedded Crohn's disease tissue the presence of specific M . paratuberculosis DNA was also increased . CONCLUSIONS: Whether the presence of M . paratuberculosis is connected to the inflammatory bowel disease or is a mere coincidence cannot be stated . We find this presence interesting and encouraging for further investigations.

Acta Paediatr Jpn, 1994 Oct, 36(5), 537 - 44
Mucosal immunity and strategies for novel microbial vaccines; Mestecky J et al.; Infectious diseases continue to be the leading cause of morbidity and mortality worldwide . Increased awareness of the fact that mucosal membranes are the most frequent portals of entry of pathogenic microorganisms has prompted studies aimed at the development of vaccination protocols and antigen delivery systems that would lead to an increased protection of mucosae . Although systemic and strictly local immunizations are of limited effectiveness in the induction of mucosal protection, ingestion or inhalation of antigens results in a generalized immune response manifested by the appearance of specific antibodies of the secretory immunoglobulin (Ig) isotype in external secretions due to the dissemination of IgA precursor cells from IgA-inductive lymphoid tissues . Furthermore, additional inductive sites strategically positioned at the opening of the respiratory and digestive tracts may also be suitable targets for induction of immune responses at desired effector sites . To prevent degradation and the increase of ingested antigens absorption, novel strategies including enclosure of antigens into biodegradable microspheres, liposomes or their expression in viral and bacterial vectors and plants are currently being considered . Forthcoming technological advances in antigen preparation and routes of delivery will undoubtedly have a profound impact on immunization practices in the future.

Curr Opin Pediatr, 1994 Oct, 6(5), 583 - 90
Therapeutic use of inhaled nitric oxide; Adatia I et al.; Nitric oxide is a gaseous endogenous mediator of vascular dilation, neural transmission, defense against microorganisms, and inhibitor of platelet adhesion . Endothelium-derived nitric oxide is important in the maintenance of normal vascular tone in the systemic and pulmonary circulation . The discovery of a selective pulmonary vasodilator has eluded investigators for many years . Inhaled nitric oxide can be used to selectively manipulate the pulmonary vasculature and represents an important advance in pharmacologic strategies aimed at the treatment of the diseased pulmonary circulation . Indeed, preliminary studies of the therapeutic use of inhaled nitric oxide in human pulmonary hypertension and respiratory failure are yielding encouraging and exciting results . Controlled and randomized studies will be required to show improvement in patient outcome and the absence of adverse sequelae from inhaled nitric oxide therapy.

Pharmazie, 1994 Oct, 49(10), 759 - 61
A simple cytotoxicity assay using the eucaryotic microorganism Dictyostelium discoideum; Tillner J et al.; First attempts to evaluate the potential of the cellular slime mold Dictyostelium discoideum as a model system for cytotoxic tests of potential drugs are described . Using the cell counter and analyser system, CASY 1, two parameters, cell count and mean cell volume, could be established as relevant parameters to estimate cytotoxicity . The effects on these two parameters of two well characterized drugs, the gentamycin analogue G418 and doxorubicin, are reported.

Nippon Jinzo Gakkai Shi, 1994 Oct, 36(10), 1175 - 83
{Changes in residual dextrose and amount of total protein loss in the effluent during the clinical course of continuous ambulatory peritoneal dialysis-related peritonitis}; Wakabayashi Y; Solute permeability of the peritoneum accelerates considerably in continuous ambulatory peritoneal dialysis (CAPD)-related peritonitis . Residual dextrose (RD) (g/bag) and the amount of total protein loss (LP) (g/bag) in the effluent of dialysate were measured during the clinical course of 21 cases of CAPD-related peritonitis as markers of deranged peritoneal permeability . The following were the results obtained: 1) In 15 cases of intraluminal infection (simple peritonitis by microorganism contamination through the lumen of a peritoneal catheter), RD decreased on day 1 (p < 0.001) and day 3 (p < 0.001) after the onset of peritonitis, and LP increased on day 1 (p < 0.001) and day 3 (p < 0.01), compared to the values of the non-infected phase . Both parameters were restored on day 7 and day 14 by adequate therapeutic maneuver . 2) In 6 cases of periluminal infection (peritonitis caused by an organic lesion of infection along the peritoneal catheter), RD and LP persisted even on day 7 (p < 0.01), and recovered 10 days after surgical removal of the peritoneal catheter with simultaneous catheter replacement . It is concluded that both RD and LP are valuable markers in the evaluation of the clinical course of CAPD-related peritonitis, and are useful in deciding on therapeutic intervention.

Aust Dent J, 1994 Oct, 39(5), 310 - 5
Physiopathology of primary periodontitis associated with plaque . Microbial and host factors . A review . Part 2; Liebana J et al.; To a considerable extent, host factors condition the initiation and progression of periodontitis . The integrity of the periodontal structures and the immune elements in the gingival fluid may act as a defensive barrier against microorganisms . However, immune over-response may lead to tissue damage and bone resorption from anaphylactic reactions, immunocomplex reactions, type IV hypersensitivity, complement hyperactivation via the alternative pathway, or direct action of leukocytes and macrophages . Moreover, insufficient host response allows bacteria to escape control, allowing more rapid progression of the disease.

Dermatol Clin, 1994 Oct, 12(4), 703 - 12
American mucocutaneous leishmaniasis; Goihman-Yahr M; American mucocutaneous leishmaniasis is produced by several species of Leishmania . The microorganism lives in jungle reservoirs and is transmitted by sandflies . After infection, a complex set of immunologic phenomena takes place . Most lesions tend to heal, but some clinical forms are relentlessly progressive and resistant to available therapy . Diagnosis is usually possible with classical or modern techniques . Current treatment is effective in most cases, but it is expensive and difficult to manage under field conditions . Research on the immune response has been interesting, and vaccine prevention and treatment are objects of current interest . American leishmaniasis may not always remain a sylvan disease, and urban adaptation is a distressing possibility.

Chemosphere, 1994 Oct, 29(8), 1735 - 42
Effect of hydrogen on the pathway and products of PCB dechlorination; Sokol RC et al.; The pathway and products of reductive dechlorination of 2,3,4-chlorobiphenyl by Hudson River sediment microorganisms were altered by H2 . Under H2/CO2, 2,3,4-CBP was dechlorinated to 2,4-,2,3-, and then 2-CBP . On the other hand, under N2, the same organisms yielded only 2,4-CBP as they did under N2/CO2 . Dechlorination was not inhibited by a single or periodic addition of a methanogenic inhibitor, 2-bromoethanesulfonic acid under all gas atmospheres and thus, methane production was not necessary for dechlorination.

Berl Munch Tierarztl Wochenschr, 1994 Oct, 107(10), 342 - 7
{The problem of a high content of vitamin A in the liver of calves, cattle, sheep and swine for the consumer . Amount of accumulation and mechanism of teratogenic effect (review article)}; Kolb E; Cases of hypervitaminosis A in men--especially in pregnant women, with development of malformations--are reported . The existence of withdrawal times to slaughter after the application of vitamin-A-containing preparations with a content of 10,000 to 10(6) international units and more is described . The content of vitamin A in the liver of monogastric animals is closely related to that in the feed . In ruminants about 40 to 70% of the vitamin A of the feed is decomposed by the microorganisms in the forestomachs . The amount of vitamin A stored in the liver after a therapeutic application is dependent of the initial content . The velocity of the depletion of the stores at a carotene- and vitamin-A-poor feeding is described . In ruminants and pigs in the account of the properties of the placenta no embryotoxicity of a therapeutic dose of vitamin A is to be expected . The mechanism of the teratogenesis by vitamin A in mice is described.

Shock, 1994 Oct, 2(4), 301 - 10
The complement system in trauma-related and ischemic tissue damage: a brief review; Mollnes TE et al.; There is increasing evidence that the complement system plays an important role in tissue damage associated with trauma and ischemia . In the present review we focus on some principles of importance for a basic understanding of the complement system, particularly aimed at those not working in this field . Complement is activated by its ability to discriminate between self and non-self, primarily as a defense against microorganisms . The activation induces an inflammatory reaction which may lead to harmful effects on the host, either as local tissue damage or, in case of an extensive systemic activation, as breakdown of homeostatic mechanisms . Complement-mediated inflammation is important not only in specific immunological defense reactions, but also in the induction of tissue injury by ischemia, hypothermia or other general tissue-damaging factors . Major trauma leads to systemic complement activation and complications to trauma may enhance the activation and increase the risk of development of the whole body inflammatory reaction and even of a fatal outcome . To protect the host against self-damage, complement activation is controlled by a series of regulatory proteins inhibiting at the various levels of the cascade . Intervening with complement activation using regulatory proteins like soluble complement receptor 1 has provided direct evidence for the importance of complement in tissue damage in various experimental models . Therapeutic complement intervention using a similar approach may be a useful tool in selected patients to attenuate the degree of complement activation and thereby reduce the total inflammatory load.

Avian Dis, 1994 Oct-Dec, 38(4), 922 - 7
Beak infection by Penicillium cyclopium in a macaw (Ara ararauna); Bengoa A et al.; A case of localized beak infection by Penicillium cyclopium in a macaw (Ara ararauna) is described . A necrotic lesion, with destruction of the corneous layer, was localized in the upper zone of the beak . Diagnosis was carried out on samples of the affected zone by direct microscopic observation, routine fungal culturing techniques, and scanning electron microscopy . Results were consistent: P . cyclopium was the only microorganism associated with the lesion site . No previous reports concerning this type of beak pathology have been found in the literature.

Am J Reprod Immunol, 1994 Oct, 32(3), 200 - 10
The value of amniotic fluid interleukin-6, white blood cell count, and gram stain in the diagnosis of microbial invasion of the amniotic cavity in patients at term; Gomez R et al.; PROBLEM: Subclinical microbial invasion of the amniotic cavity occurs in 18.8% of women with term labor and intact membranes and in 34% of patients with term PROM and is a risk factor for the development of puerperal infection related morbidity . Although amniotic fluid white blood cell count, interleukin-6 determination, and Gram stain examination have been used for the diagnosis of intrauterine infection in patients with preterm labor and preterm premature rupture of membranes, no information is available about the accuracy and specific cut-off values for these tests in patients at term . The purpose of this study was to compare the performance of the amniotic fluid Gram stain examination, white blood cell count, and interleukin-6 determination in the identification of microbial invasion of the amniotic cavity in patients at term with and without PROM . METHOD: Amniotic fluid was retrieved from 148 patients with term gestations (90 patients with spontaneous labor and intact membranes and 58 patients with PROM) . Samples were cultured for bacteria and Mycoplasma species . Amniotic fluid Gram stain, white blood cell count, and interleukin-6 determinations (ELISA, sensitivity: 43 pg/ml) were performed in all samples . Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture for microorganisms . Analysis was conducted using Mann-Whitney U test, Fisher's exact test, receiver operating characteristic curves and logistic regression . RESULTS: Patients with spontaneous labor and intact membranes: The prevalence of microbial invasion of amniotic cavity in this group was 15.6% (14/90) . The most sensitive test for the detection of microbial invasion of the amniotic cavity was amniotic fluid interleukin-6 determination (sensitivity for: interleukin-6 > or = 5.7 ng/ml = 86%, white blood cell count > or = 20 cells/mm3 = 64%, Gram stain = 28%) . The most specific test was the Gram stain of the amniotic fluid (specificity for: Gram stain = 84%, interleukin-6 = 79% and white blood cell count = 63%) . Multiple logistic regression demonstrated that amniotic fluid interleukin-6 concentration was the only covariate that retained statistical significance when intrauterine infection was used as outcome variable . Patients with PROM: The prevalence of a positive amniotic fluid culture in this group was 39.7% (23/58) . Logistic regression demonstrated that only interleukin-6 retained a significant relationship with the results of amniotic culture when all variables were entered simultaneously into a model to predict amniotic fluid culture results . The most sensitive tests for the detection of intrauterine infection were interleukin-6 determination and white blood cell count (sensitivity for interleukin-6 > or = 3.4 ng/ml and white blood cell count > or = 20 cells/mm3 = 69.6% for both) . The most specific test was Gram stain (97.1%) . CONCLUSIONS: Amniotic fluid interleukin-6 determination is the best rapid test for the detection of microbial invasion of the amniotic cavity in patients at term with and without PROM . When this test is not available, amniotic fluid Gram stain and white blood cell count represent valid diagnostic tools to assess the microbial state of amniotic cavity.

Environ Health Perspect, 1994 Oct, 102 Suppl 4, 25 - 30
A perspective on the potential development of environmentally acceptable light-duty diesel vehicles; Hammerle R et al.; Between 1979 and 1985, an international technical focus was placed upon potential human health effects associated with exposure to diesel emissions . A substantial data base was developed on the composition of diesel emissions; the fate of these emissions in the atmosphere; and the effects of whole particles and their chemical constituents on microorganisms, cells, and animals . Since that time, a number of significant developments have been made in diesel engine technology that require a new look at the future acceptability of introducing significant numbers of light-duty diesel automobiles into the European and American markets . Significant engineering improvements have been made in engine design, catalysts, and traps . As a result, particle emissions and particle associated organic emissions have been reduced by about 10 and 30 times, respectively, during the past 10 years . Research studies to help assess the environmental acceptability of these fuel-efficient engines include the development of an emissions data base for current and advanced diesel engines, the effect of diesel emissions on urban ozone formation and atmospheric particle concentrations, the effect of fuel composition, e.g., lower sulfur and additives on emissions, animal inhalation toxicology studies, and fundamental molecular biology studies.

Mol Cell Biol, 1994 Oct, 14(10), 6597 - 606
Two FK506 resistance-conferring genes in Saccharomyces cerevisiae, TAT1 and TAT2, encode amino acid permeases mediating tyrosine and tryptophan uptake; Schmidt A et al.; The macrocyclic lactone FK506 exerts immunosuppressive effects on T lymphocytes by interfering with signal transduction leading to T-cell activation and also inhibits the growth of eukaryotic microorganisms, including Saccharomyces cerevisiae . We reported previously that an FK506-sensitive target in S . cerevisiae is required for amino acid import and that overexpression of two new genes, TAT1 and TAT2 (formerly called TAP1 and TAP2), confers resistance to the drug . Here we report that TAT1 and TAT2 encode novel members of the yeast amino acid permease family composed of integral membrane proteins that share 30 to 40% identity . TAT1 is the tyrosine high-affinity transporter, which also mediates low-affinity or low-capacity uptake of tryptophan . TAT2 is the tryptophan high-affinity transporter . FK506 does not reduce the levels of TAT1 and TAT2 transcripts, indicating that the inhibition of amino acid transport by the drug is posttranscriptional.

Tidsskr Nor Laegeforen, 1994 Sep 30, 114(23), 2722 - 4
{Biological pollution of indoor air}; Becher R et al.; Biological pollution of indoor air can consist of viruses, bacteria, fungi, fungal spores, mites, dander and metabolic products from the microorganisms . The occurrence of such pollution can occasionally cause building-related adverse health effects . Allergens produced by house dust mites and in the dander of furred domestic animals are generally regarded to be among the most important causes of disease episodes in atopic individuals . Bacteria and fungi as such cause building-related disease more rarely . An exception is respiratory infections caused by Legionella bacteria . Other possible health effects of biological indoor air pollution have been suggested, but the data are inconclusive.

Proc Natl Acad Sci U S A, 1994 Sep 27, 91(20), 9584 - 7
A physical map of the Myxococcus xanthus chromosome; He Q et al.; A physical map of the 9.2-Mbp Myxococcus xanthus DK1622 chromosome at a resolution of 25 kbp was constructed by using a strategy that is applicable to virtually all microorganisms . Segments of the chromosome were used as hybridization probes to subdivide a yeast artificial chromosome (YAC) library into groups of linked clones . The clones were aligned by comparing their EcoRI restriction patterns . The groups of YAC clones ("contigs") were oriented and aligned with the genomic restriction map by means of common genetic and physical markers such as rare restriction sites and transposon insertions . Over 95% of the genome is represented by cloned DNA . Sixty genetic loci including > 100 genes, many of which play a role in fruiting body development, have been mapped in this way . Additional genes can now be located on the chromosome map by hybridization of their sequences to the ordered set of YAC chromosomes . The mapped genetic loci account for approximately 2% of the genome.

FEBS Lett, 1994 Sep 26, 352(2), 146 - 50
Herbivore-induced volatiles: the emission of acyclic homoterpenes from leaves of Phaseolus lunatus and Zea mays can be triggered by a beta-glucosidase and jasmonic acid; Hopke J et al.; The treatment of healthy, undamaged plants of the Lima bean Phaseolus lunatus with solutions of a beta-glucosidase from bitter almonds (at 5 U.ml-1) through the petiole results in an enhanced emission of volatiles to the environment . The compounds are identical with those emitted in response to infestation with the red spotted spider mite Tetranychus urticae . Dominant products are the two acyclic homoterpenes 4,8-dimethyl-1,3E,7- dimethylnonatriene (homoterpene I) and 4,8,12-trimethyl-1,3E,7E,11-tridecatetraene (homoterpene II) which are of sesquiterpenoid and diterpenoid origin . Therefore, a beta-glucosidase of the herbivore may be considered as the true elicitor for the odor induction . Homoterpene I and most other of the herbivore-induced volatiles can also be triggered by treatment of the plant with solutions of jasmonic acid (JA) at 100 nmol.ml-1 to 10 mumol.ml-1 . The C16 homoterpene II is not significantly induced by JA . The time-course of the enzymatic- and the JA-triggered induction of the volatiles is identical . The dose-response to JA parallels previous reports on alkaloid induction in cell cultures . In corn plants (Zea mays) JA triggers the emission of all volatiles which are known to be emitted in response to the damage by the beet army worm Spodoptora exigua . In summary, the emission of volatiles after damage by a herbivore resembles the production of phytoalexins in response to an attacking microorganism and uses similar elicitors and internal transduction pathways.

Structure, 1994 Sep 15, 2(9), 809 - 21
Crystal structure of the FAD-containing fragment of corn nitrate reductase at 2.5 A resolution: relationship to other flavoprotein reductases; Lu G et al.; BACKGROUND: In the biological assimilation of nitrate in plants and microorganisms, nitrate is reduced to ammonium by transfer of eight electrons in a two-step process . The first step of the pathway, the reduction of nitrate to nitrite, is catalyzed by nitrate reductase, a multi-redox cofactor enzyme which belongs to the class of flavoprotein pyridine nucleotide cytochrome reductases . The enzyme can be divided into three functional fragments that bind the cofactors molybdopterin, heme-iron and flavin adenine dinucleotide (FAD)/nicotinamide adenine dinucleotide (NADH) . RESULTS: Here we describe the crystal structure of the recombinant cytochrome b reductase fragment of corn nitrate reductase, in complex with the cofactor FAD, determined to 2.5 A resolution . This catalytically competent fragment of nitrate reductase consists of two domains, the amino-terminal lobe, which binds FAD, and the carboxy-terminal lobe, which presumably binds NADH, connected by a linker region . CONCLUSIONS: Nitrate reductase belongs to the class of flavoprotein pyridine nucleotide cytochrome reductases, a subgroup in the family of ferredoxin reductase-like flavoproteins . Comparison with other members of this family reveals that large structural differences are found in the relative orientation of the cofactor binding lobes . This indicates that conformational changes might be important for biological function.

Biochem Biophys Res Commun, 1994 Sep 15, 203(2), 1251 - 8
A bacterial nitric oxide synthase from a Nocardia species; Chen Y et al.; Nitric oxide synthase (EC 1.14.23) was discovered in a Nocardia species . The bacterial nitric oxide synthase was purified as much as 380 fold by affinity chromatography over 2',5'-ADP-agarose . The partially purified enzyme required NADPH, O2, CA++, FAD, FMN, and tetrahydrobiopterin as cofactors in the conversion of L-arginine to L-citrulline and nitric oxide . The apparent Km for L-arginine was determined to be 8.2 microM, and the Vmax was 840 nmole NADPH consumed/min/mg protein . The enzyme was competetively inhibited by NG-nitro-arginine with an apparent Ki of 14.6 microM . The experimental evidence provides confirmation of the first microbial nitric oxide synthase in microorganisms.

Am J Obstet Gynecol, 1994 Sep, 171(3), 784 - 90
Simultaneous detection of three common sexually transmitted agents by polymerase chain reaction; Mitrani-Rosenbaum S et al.; OBJECTIVE: Human papillomaviruses, herpes simplex viruses, and Chlamydia trachomatis are very common infections of the genital tract . The purpose of our study was to develop a polymerase chain reaction-based assay for the simultaneous detection of these organisms from a single genital swab . STUDY DESIGN: To prove the technical feasibility of a simultaneous polymerase chain reaction assay for these organisms, a mixture of deoxyribonucleic acids extracted from cells infected by these three agents was amplified in the same tube with three different sets of primers corresponding to specific regions of the human papillomavirus genome, the herpes simplex virus 1 and 2 genomes, and the Chlamydia trachomatis plasmid, respectively . Then genital swabs from patients with suspected infection by one or more of these agents were assayed by polymerase chain reaction for the presence of herpes simplex virus, human papillomavirus, and Chlamydia trachomatis independently and simultaneously . Most of the samples were analyzed in parallel by other methods: herpes simplex virus by culture., Chlamydia trachomatis by culture and antigen staining, and human papillomavirus by the filter in situ hybridization method . RESULTS: Analysis of the polymerase chain reaction products amplified from the deoxyribonucleic acid mixture revealed three bands corresponding to the respective amplified region of each microorganism . A total of 391 genital swabs were assayed independently by polymerase chain reaction for the presence of herpes simplex virus (113 samples), human papillomavirus (200 samples), and Chlamydia trachomatis (78 genital swabs and four urethral swabs) . Forty-nine were herpes simplex virus positive (47 by culture), 45 were human papillomavirus positive (43 by filter in situ hybridization), and one sample was positive for Chlamydia trachomatis, both by polymerase chain reaction and by culture . Ninety-two of the 391 samples were analyzed simultaneously by polymerase chain reaction for the presence of the three agents . The correlation between the results obtained independently and simultaneously was of the order of 100%: 29 were positive for herpes simplex virus, 16 were positive for human papillomavirus, and one was positive for Chlamydia trachomatis, in one sample we could detect both human papillomavirus and herpes simplex virus . CONCLUSIONS: The polymerase chain reaction simultaneous assay is a quick and efficient way of detecting herpes simplex virus, human papillomavirus, and Chlamydia trachomatis from a single genital swab . This method can greatly simplify the diagnostic procedures in the laboratory.

J Environ Sci Health B, 1994 Sep, 29(5), 963 - 87
Cometabolic degradation of acifluorfen by a mixed microbial culture; Andreoni V et al.; Laboratory experiments were conducted to study the degradation of acifluorfen 5-{2-chloro-4-(trifluoromethyl)-phenoxyl}-2-nitrobenzoic acid by a mixed microbial population . Concentrations of acifluorfen up to 100 mg/l had no inhibitory effect on the growth of microbial culture . The microorganisms degraded acifluorfen through a cometabolic process in presence of 2-nitrobenzoate . The degradation rate of acifluorfen, determined by liquid chromatography analysis in batch cultures incubated under oxygen-limited conditions were compared . The degradation was slower under oxygen than oxygen-limited conditions . Aminoacifluorfen was produced in both conditions.

Infect Immun, 1994 Sep, 62(9), 4005 - 14
Localized expression of mRNA for phagocyte-specific chemotactic cytokines in human periodontal infections; Tonetti MS et al.; In bacterial infections, mononuclear and polymorphonuclear phagocytes are key components of host defenses . Recent investigations have indicated that chemokines are able to recruit and activate phagocytes . In particular, interleukin-8 (IL-8) attracts polymorphonuclear leukocytes (PMNs), while monocyte chemoattractant protein-1 (MCP-1) is selective for cells of the monocyte/macrophage lineage . In this investigation, we analyzed the in situ expression of IL-8 and MCP-1 mRNAs in human periodontal infections . Specific mRNA was detected by in situ hybridization using 35S-labeled riboprobes in frozen tissue sections . Phagocytes (PMNs and macrophages) were specifically detected as elastase-positive or CD68+ cells by a three-stage immunoperoxidase technique . Results indicated that expression of phagocyte-specific cytokines was confined to selected tissue locations and, in general, paralleled phagocyte infiltration . In particular, IL-8 expression was maximal in the junctional epithelium adjacent to the infecting microorganisms; PMN infiltration was more prominent in the same area . MCP-1 was expressed in the chronic inflammatory infiltrate and along the basal layer of the oral epithelium . Cells of the monocyte/macrophage lineage were demonstrated to be present in the same areas . The observed expression pattern may be the most economic way to establish a cell-type-selective chemotactic gradient within the tissue that is able to effectively direct polymorphonuclear phagocyte migration toward the infecting microorganisms and modulate mononuclear phagocyte infiltration in the surrounding tissues . This process may optimize host defenses and contribute to containing leukocyte infiltration to the infected and inflamed area, thus limiting tissue damage.

Minerva Chir, 1994 Sep, 49(9), 829 - 36
Antibiotic prophylaxis in elective neurosurgery . Epidemiological study; Santilli F et al.; The authors present an epidemiological study of patients who have undergone elective neurosurgery and who have been treated with different types of antibiotics throughout a ten year time span . From the statistic analysis of the different parameters taken into consideration (administering modalities of the short-term and long-term antibiotic, type of sepsis encountered, isolated microorganisms) the authors show, as a result, that the long-term antibiotic prophylaxis is a clearly improper method; the short-term prophylaxis is a correct method the effect of which is, however, still controversial as it does not modify a natural low percentage of infections in elective neurosurgery . The role given to the antibiotic seems much less important compared with the adoption of correct antiseptic measures and of proper nursing.

Nutr Rev, 1994 Sep, 52(9), 311 - 5
Iron-copper interactions: some new revelations; Harris ED; Iron and copper show an uncommon but largely unexplained interdependence, the basis for which is being clarified in hemoglobin-synthesizing cells, yeast, and photosynthetic microorganisms . The interactions of the two metals with membrane transport systems and genetic regulators are more apt to be cooperative than antagonistic.

Z Lebensm Unters Forsch, 1994 Sep, 199(3), 219 - 21
{Determination of the number of somatic cells in raw milk using the REF method}; Faltusz E; A rapid and sensitive method of determining the number of somatic cells in milk will be presented . By this method, based upon an innovative processing of milk solubilisation, it is possible at first to determine simultaneously the diverse microorganisms which are also present . The method requires only chemicals which are harmless to the environment.

Undersea Hyperb Med, 1994 Sep, 21(3), 277 - 86
Effects of deep saturation diving on the lymphocyte subsets of healthy divers; Shinomiya N et al.; We examined the effect of deep saturation diving on the host defense mechanisms of five healthy volunteers using fluorescein-dye-conjugated monoclonal antibodies . Six divers engaged in a 440-m saturation diving simulation with total hyperbaric exposure of 30 days; five served as subjects . Change in the expression of surface molecules on the lymphocytes was analyzed during that period . Blood samples were serially taken on Days 4, 6, 8, 15, 22, 29, and after surfacing . The total number of lymphocytes showed no remarkable change . However, the fraction of T (CD3+) cells decreased from 68.0 +/- 3.3% to 55.8 +/- 5.8% (Day 8), and B cells increased reciprocally . In these T cells, the CD4:CD8 ratio (normally > 1.0) became less than 1.0 during compression and thereafter . In spite of the prophylactic use of anti-external otitis agents, one of the divers revealed a remarkable growth of Pseudomonas in the external auditory meatus, showing a high level of blood endotoxin (10.2 pg/ml) . These results suggest that decrease in CD4+ fraction of T lymphocytes might explain in part the decreased resistance of divers to infective microorganisms in deep saturation diving.

J AOAC Int, 1994 Sep-Oct, 77(5), 1202 - 17
Evaluation of a gas chromatographic method to identify irradiated chicken, pork, and beef by detection of volatile hydrocarbons; Schreiber GA et al.; A method suitable for routine application was used in an interlaboratory study to detect irradiation treatment of chicken carcass, pork, and beef . By using gas chromatographic analysis, 17 participating laboratories determined the quantity of 4 different radiation-induced volatile hydrocarbons (tetradecene, pentadecane, hexadecadiene, and heptadecene) in the fat fraction of coded specimens approximately 3 and 6 months after irradiation . The specimens of each type of meat were supplied by 2 different producers . The dose range tested (0.6-7.5 kGy) included levels commercially used to reduce the number of contaminating microorganisms (1-5 kGy) . The method employed permitted a correct identification of irradiated or nonirradiated in 98.3% of the 864 specimens.

Rev Prat, 1994 Sep 1, 44(13), 1786 - 91
{Infections of cutaneous wounds}; Stein A et al.; Infection of cutaneous wounds can be defined as proliferation of microorganisms at an interruption in the mucocutaneous covering . The phenomenon depends on an association of local and general factors which disturb the balance in host-pathogen interactions, in favor of the latter . In addition to infections by nonspecific pyogenic germs, whether posttraumatic or postsurgical, there are specific infections where the wound is the departure point for a systemic infection . Even today, tetanus and gaseous gangrene should be apprehended and systematically prevented . Similarly, the high incidence of infection of bite or scratch wounds (animal or human) should suggest prophylactic antibiotic treatment as well as evaluation of the risk of rabies in the case of animal bites or scratches . In any case, even if antibiotic treatment must be undertaken as an emergency measure, previous bacteriological investigation should be carried out if possible since it permits subsequent adaptation in case of failure of the initial antibiotic treatment.

J Gerontol Nurs, 1994 Sep, 20(9), 8 - 14
Protecting the skin from moisture and associated irritants; Kemp MG; 1 . Skin that is damp or wet is more permeable to irritating substances and more readily colonized by microorganisms . Less friction is required to abrade or blister skin when it is damp . 2 . The goal of nurses who care for patients at risk for skin breakdown secondary to moisture and associated irritants is to keep the skin dry and free of irritants . 3 . Although there are many products that claim to protect the skin from the injurious effects of moisture, the research supporting these claims is limited . Nurses, therefore, must be inquisitive and vigilant when selecting products.

Ann Emerg Med, 1994 Sep, 24(3), 490 - 502
Molecular methods: applications for clinical infectious diseases; Engleberg NC; The application of molecular biology to microbiology has led to a surge of new information about most infectious microorganisms, the pathogenesis of the infections they cause, and the specific microbial antigens involved in the immune response to these infections . The simultaneous application of the same techniques to diagnosis and epidemiology has also shown great promise, but these developments have not yet had a major effect on the routine practice of medicine . For some purposes, direct probe tests perform as well as other available methods . However, for most infections, these methods have not been proven sufficiently sensitive . The latest generation of highly sensitive diagnostics based on the polymerase chain reaction will overcome this technical obstacle and may revolutionize the management of many infections . Difficulties inherent in performing these tests will require special procedures and training in clinical laboratories to ensure that they are performed reliably . Nucleic acid-based methods for epidemiologic typing of microorganisms and for identification of noncultivatable pathogens are particularly useful for analysis of poorly cultivatable, dangerous, or otherwise untypeable microorganisms.

Microbiologia, 1994 Sep, 10(3), 297 - 304
{Application of immunologic methods to the analysis of bio-leaching bacteria}; Coto O et al.; Pure cultures of Thiobacillus ferrooxidans and mixed cultures of Thiobacillus ferrooxidans and Leptospirillum ferrooxidans isolated from the Matahambre mine (Cuba) were used to fit immunodiffusion and immunoelectron microscopy to the study of iron oxidizing bacteria . The possibilities, advantages and limits of those techniques have been studied from both the identification and the serological characterization points of view . Finally, the efficiency of these methods was tested by applying them to the identification of microorganisms from acidic waters from the mine.

Int Angiol, 1994 Sep, 13(3), 196 - 201
Arterial aneurysms in Behçet's disease; Bastounis E et al.; Six cases of arterial aneurysms, due to "Behcet's disease" located in various arteries are presented . Surgical reconstruction included: Resection of the lesions and replacement with corresponding grafts with satisfactory results . In spite of the macroscopic similarity of the aneurysms found in "Behcet's disease" as compared to those of mycotic origin, the presence of any microorganism could not be detected in various cultures or pathological specimens . Meticulous diagnosis on the nature of the aneurysm, close follow-up and careful postoperative anticoagulant treatment, is imperative for satisfactory immediate and late results.

Int J Pept Protein Res, 1994 Sep, 44(3), 245 - 52
alpha-Amylases from Thermoactinomyces vulgaris: characteristics, primary structure and structure prediction; Hansen G et al.; Two amylolytic active protein fractions (named alpha-amylase 1 and alpha-amylase 2) were isolated from the bacterium Thermoactinomyces vulgaris strain 94-2A . alpha-Amylase 1 had a molecular mass of 51.6 kDa, whereas alpha-amylase 2 consists of two fragments which have molecular masses of 17.0 and 34.6 kDa, respectively . These two fragments are products from a proteolytic cleavage of alpha-amylase 1 at amino acid position 303 (tryptophan) by a serine protease (thermitase) which is also produced by T . vulgaris . The purified alpha-amylase 1 and 2 follow the Michaelis-Menten kinetics in the presence of starch as substrate with Km values of 1.37 +/- 0.07 and 1.29 +/- 0.18 mg/mL, respectively . In effect they differ in their stability characteristics . The amino acid sequence of alpha-amylase from T . vulgaris derived from DNA sequence (1) was compared with those of other alpha-amylases . It reveals high homologies to alpha-amylases from other microorganisms (e.g . B . polymyxa, A . oryzae, S . occidentalis and S . fibuligera) . A three-dimensional structure model for alpha-amylase 1 on the basis of the 3 A X-ray structure of Taka-amylase was constructed.

J Immunol, 1994 Sep 1, 153(5), 2146 - 52
Effect of aging on murine macrophages . Diminished response to IFN-gamma for enhanced oxidative metabolism; Ding A et al.; The ability of macrophages to secrete reactive oxygen intermediates, as well as reactive nitrogen intermediates, correlates closely with their capacity to perform two critical effector functions: intracellular killing of microorganisms and lysis of tumor cells . In this study, age-associated changes in the ability of caseinate-elicited peritoneal macrophages to release hydrogen peroxide were determined . Macrophages from aged BALB/c mice produced 50% less hydrogen peroxide than those from young mice in response to PMA or opsonized zymosan . In contrast, the production of macrophage-activating cytokines including IFN-gamma was not diminished in splenocyte supernatants from the aged group . Furthermore, no difference was detected in surface expression of IFN-gamma receptor in old and young mice . Macrophage responses to IFN-gamma, however, declined with aging . In vitro, IFN-gamma-induced release of hydrogen peroxide and nitric oxide was 50% lower in old mice than in young mice . IFN-gamma-induced tyrosine phosphorylation of MAPK, an early activation event, was undetectable in macrophages from the aged mice . These data demonstrate that diminished responses of macrophages to activating signals are one aspect of the impaired immune response in aged mice.

J Biol Chem, 1994 Aug 26, 269(34), 21415 - 9
Discovery of a new type of sialidase, "KDNase," which specifically hydrolyzes deaminoneuraminyl (3-deoxy-D-glycero-D-galacto-2-nonulosonic acid) but not N-acylneuraminyl linkages; Kitajima K et al.; The release of 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN, deaminoneuraminic acid) residues from their alpha-ketosidic linkage is required to determine the structural and functional role of KDN-glycoconjugates in sources as disparate as trout egg polysialoglycoproteins and human cancers . We report for the first time the isolation and characterization of a novel type of sialidase (KDNase), which specifically hydrolyzes KDN ketosidic but not N-acylneuraminyl linkages . KDNase activity was assayed using 4-methylumbelliferyl KDN (4-MU-KDN) . A KDNase-producing microorganism was identified as Sphingobacterium multivorum . The affinity-purified enzyme was designated KDNase SM to denote its origin and that it was free of N-acylneuraminidase, proteolytic, and other glycosidase activities . KDNase SM activity toward 4-MU-KDN was not inhibited by the N-acylneuraminidase inhibitor, 2,3-dehydro-2-deoxy-N-acetylneuraminic acid . KDNase SM released free KDN from naturally occurring substrates, including (KDN)GM3, KDN-glycoprotein, which bears a number of O-linked chains of KDN alpha 2-->3Gal beta 1-->3GalNAc alpha 1-->3 (KDN alpha 2-->(-->8KDN alpha 2-->)n-->6)GalNAc alpha 1-->, and the biantennary complex-type of N-glycan, KDN alpha 2-->3Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->6(KDN alpha 2-->3Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->3)Man beta 1-->4GlcNAc beta 1-->4GlcNAc . KDNase SM thus exhibited a broad linkage specificity and was able to hydrolyze the KDN residues ketosidically linked alpha 2-->3, alpha 2-->6, and alpha 2-->8 . The enzyme did not release Neu5Ac or Neu5Gc from 4-MU-Neu5Ac, N-acetyl-neuraminyllactose, colominic acid, or other Sia(Neu5Ac or Neu5Gc)-containing glycoconjugates.

J Natl Cancer Inst, 1994 Aug 17, 86(16), 1222 - 7
Chronic active hepatitis and associated liver tumors in mice caused by a persistent bacterial infection with a novel Helicobacter species; Ward JM et al.; BACKGROUND: In the autumn of 1992, a novel form of chronic, active hepatitis of unknown etiology was discovered in mice at the National Cancer Institute-Frederick Cancer Research and Development Center (NCI-FCRDC), Frederick, Md . A high incidence of hepatocellular tumors occurred in affected animals . The disease entity was originally identified in A/JCr mice that were untreated controls in a long-term toxicologic study . PURPOSE: Our original purpose was to determine the origin and etiology of the chronic hepatitis and to quantify its association with hepatocellular tumors in mice of low liver tumor incidence strains . After a helical microorganism was discovered in hepatic parenchyma of diseased mice, we undertook characterization of the organism and investigation of its relationship to the disease process . METHODS: Hepatic histopathology of many strains of mice and rats, as well as guinea pigs and Syrian hamsters, in our research and animal production facilities was reviewed . Steiner's modification of the Warthin-Starry stain and transmission electron microscopy were used to identify bacteria in the liver . We transmitted the hepatitis with liver suspensions from affected mice and by inoculation with bacterial cultures . Bacteria were cultivated on blood agar plates maintained under anaerobic or microaerophilic conditions and characterized morphologically, biochemically, and by 16S rRNA sequence . RESULTS: We report here the isolation of a new species of Helicobacter (provisionally designated Helicobacter hepaticus sp . nov.) that selectively and persistently colonizes the hepatic bile canaliculi of mice (and possibly the intrahepatic biliary system and large bowel), causing a morphologically distinctive pattern of chronic, active hepatitis and associated with a high incidence of hepatocellular neoplasms in infected animals . CONCLUSIONS: The novel Helicobacter is a likely candidate for the etiology of hepatocellular tumors in our mice . The Helicobacter-associated chronic active hepatitis represents a new model to study mechanisms of carcinogenesis by this genus of bacteria . IMPLICATIONS: Adenocarcinoma of the stomach, the second most prevalent of all human malignancies world-wide, is associated with infection at an early age with Helicobacter pylori . Infection leads to several distinctive forms of gastritis, including chronic atrophic gastritis, which is a precursor of adenocarcinoma . H . hepaticus infection in mice constitutes the only other parallel association between a persistent bacterial infection and tumor development known to exist naturally . Study of the H . hepaticus syndrome of chronic active hepatitis and liver tumors in mice may yield insights into the role of H . pylori in human stomach cancer and gastric lymphoma.

Cancer Lett, 1994 Aug 15, 83(1-2), 123 - 8
DNA damage induced by wood preserving waste extracts in vitro without metabolic activation, as assayed by 32P-postlabeling; Randerath K et al.; Aqueous wood preserving waste (WPW) extracts were tested for their ability to damage DNA in vitro without metabolic activation . Two extracts were prepared from a surface tar and a surface clay soil sample of a WPW site . As assayed by 32P-post-labelling incubation of DNA with these extracts gave rise to highly complex, extract-specific profiles of DNA adducts whose formation depended on the concentration of WPW material . Most of the adducts appeared to be derived from polycyclic aromatic hydrocarbons (PAHs) . Three mg organic WPW residue gave rise to total adduct levels of 13.8 (extract 1) and 66.2 (extract 2) DNA modifications in 10(7) DNA nucleotides, corresponding to 13.9 and 26.9 modifications, respectively, per 10 mg of soil . Thus, extract 2 was more active, although the parent residue had a 1.4-times lower PAH content as determined by gas chromatography/mass spectrometry (GC/MS) . DNA adduct formation presumably was a consequence of (i) free radical reactions, possibly involving semiquinones and oxygen free radicals, and (ii) reaction of direct-acting electrophiles, derived from metabolism of WPW toxicants by soil microorganisms . These reactions appeared to be more active in sample 2 . The results suggest that ground water at WPW sites contains DNA-reactive compounds posing a cancer hazard to humans . The in vitro DNA adduct assay represents a novel tool to readily assess this type of hazard and the possible effects of remediation measures.

Clin Exp Immunol, 1994 Aug, 97 Suppl 2, 4 - 9
Collectins, collectin receptors and the lectin pathway of complement activation; Malhotra R et al.; The collectins are a group of soluble multimeric lectins, which contain collagenous segments, and resemble the complement protein C1q in aspects of their structures and functions . This group of proteins, which includes MBP, SP-A, SP-D, conglutinin and CL-43, are known to act as opsonins in various circumstances, and are likely to have roles in innate immunity . The focus of current research is to pursue the hypothesis that the collectins recognize and bind to non-host carbohydrate structures on microorganisms and particles, and participate in the processing or elimination of such material, either by direct interaction with phagocytic cell receptors, or by indirect routes such as complement activation Publication Types:

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