Appl Environ Microbiol, 1997 May, 63(5), 1883 - 8 In vivo levels of chlorinated hydroquinones in a pentachlorophenol-degrading bacterium; McCarthy DL et al.; Sphingomonas chlorophenolica RA-2 is a soil microorganism that can grow on pentachlorophenol (PCP) as a sole carbon source . In this microorganism, PCP is converted to tetrachlorohydroquinone (TCHQ), trichlorohydroquinone, and 2,6-dichlorohydroquinone . The remainder of the pathway has not yet been defined . The ability to grow on PCP as a sole carbon source is remarkable because of the toxicity of PCP and its chlorinated hydroquinone metabolites . Experiments in which the levels of PCP and chlorinated hydroquinones were measured in cells metabolizing {U-14C}PCP revealed that the levels of chlorinated hydroquinones in the cytoplasm are in the low micromolar range . The toxicity of chlorinated hydroquinones was evaluated by exposure of Escherichia coli cells that had been treated with EDTA (to remove the outer membrane) to TCHQ . Significant toxicity due to TCHQ was not apparent until concentrations of 500 microM and higher . Thus, an important part of the explanation for why S . chlorophenolica RA-2 is able to grow on PCP as a sole carbon source is undoubtedly that it can process sufficient carbon for growth without accumulating high levels of toxic intermediates. Appl Environ Microbiol, 1997 May, 63(5), 1739 - 43 Cyclosporin C is the main antifungal compound produced by Acremonium luzulae; Moussaif M et al.; A strain of Acremonium luzulae (Fuckel) W . Gams was selected in screening new microorganisms for biological control of fruit postharvest diseases, especially gray and blue mold diseases on apples and strawberries . This strain manifests a very strong activity against a large number of phytopathogenic fungi . In this work, the product responsible for this antifungal activity was isolated from modified Sabouraud dextrose broth cultures of A . luzulae . It was purified to homogeneity by reverse-phase column chromatography . On the basis of UV, infrared, and 1H and 13C nuclear magnetic resonance spectra, mass spectral analysis, and the amino acid composition of the acid hydrolysates, the antibiotic was determined to be cyclosporin C . Cyclosporin C showed a broad-spectrum activity against filamentous phytopathogenic fungi but no activity against bacteria or yeasts . Its antifungal activity is only fungistatic . In contrast to Tolypocladium inflatum, another cyclosporin-producing strain, A . luzulae, did not produce additional cyclosporins . This was confirmed by in vivo-directed biosynthesis. J Cell Physiol, 1997 May, 171(2), 179 - 89 From newborn to adult: phenotypic and functional properties of skin equivalent and human skin as a function of donor age; Michel M et al.; The skin's most important function is to act as a barrier against fluid loss, microorganism infections, and percutaneous absorption . To fulfill this role, keratinocytes proliferate and differentiate to produce a protective layer: the stratum corneum . Because stem cells are responsible for the production of differentiated progeny and stem cells (K19-expressing cells) are less abundant in skin from older donors, the purpose of this study was to establish whether histological and functional properties of differentiating skin is influenced by donor age . The in vitro model developed for the evaluation of skin properties (Michel et al., 1995) was used to produce skin equivalents from newborn, child, and adult keratinocytes . Throughout maturation, skin equivalents were compared with corresponding skin biopsies for keratin, filaggrin, and transglutaminase expression . Percutaneous absorptions of hydrocortisone also were measured and correlated with lipid content . After 1 wk of immersed culture, the epidermal layer of newborn skin equivalents was thicker than child and adult epidermis . As expected, a greater proportion of cutaneous stem cells was present in newborn compared with children and adult skin equivalents . No age-related difference was observed for differentiation markers . When skin equivalents were cultured at the air-liquid interface, cell differentiation and stratum corneum formation were induced, and the age-related variation in the thickness of the epidermal layer disappeared . Percutaneous absorption through these matured skin equivalents did not vary with age . Their lipid density and profile were similar . Accordingly, skin biopsies exhibited comparable percutaneous absorption profiles independently of donor age . In conclusion, although newborn skin equivalents, or skin biopsies, contained more stem cells than child and adult counterparts, no age-related histological difference was observed in the differentiated tissues . Moreover, the functional barrier property of skins and matured skin equivalents did not vary with age . Therefore, both newborn and adult keratinocytes produce useful in vitro models to study epidermal differentiation processes involved in both normal and pathological states. J Immunol, 1997 May 1, 158(9), 4444 - 51 Properdin, a positive regulator of complement activation, is released from secondary granules of stimulated peripheral blood neutrophils; Wirthmueller U et al.; Properdin is an important regulatory constituent of the complement system . In contrast to most other components of complement, biosynthesis of properdin is restricted to a few cell types only, i.e., monocytes/macrophages and peripheral blood T cells . This report demonstrates the presence of properdin mRNA in peripheral blood granulocytes and shows that properdin is stored in the granules of human neutrophils and secreted upon stimulation with TNF-alpha, C5a, IL-8, or FMLP . Subcellular fractionation using Percoll density gradients and Western blot analyses revealed that the bulk of properdin is contained in the secondary granules . Moreover, flow cytometric analyses indicated that properdin is present on the surface of neutrophils . In contrast to alternative pathway components, components of the classical pathway of complement activation, such as C2 and C4, were not detected . Our findings suggest that neutrophils can actively stabilize and amplify the alternative activation pathway of complement by secretion of properdin as part of the innate defense against microorganisms. Microsc Res Tech, 1997 Apr 15, 37(2), 116 - 35 Epibiotic microorganisms on copepods and other marine crustaceans; Carman KR et al.; Although the occurrence of microbial (algal, protozoan, bacterial, and fungal) epibionts on marine crustaceans and other invertebrates has been documented repeatedly, the ecological context and significance of these relationships generally are not well understood . Recently, several studies have examined the population and community ecology of algal and protozoan epibionts on freshwater crustaceans . Even so, the study of microbial epibionts in aquatic environments is still in its infancy . In this review, we summarize associations of microalgae, protozoans, and bacteria with marine crustaceans, especially copepods . We note differences and commonalities across epibiont taxa, consider host-epibiont cycling of nutrients, generate hypotheses relevant to the ecology of the host and the epibiont, and suggest future research opportunities. Med Clin (Barc), 1997 Apr 12, 108(14), 521 - 3 {Yield of blood cultures in relation to the cultured blood volume in Bactec 6A bottles}; Mensa J et al.; BACKGROUND: Concentration of microorganisms in blood is low in bacteremia from extravascular sources . The best yield from blood cultures is achieved by culturing a minimum of 10-20 ml, although in some processing blood culture systems such as Bactec NR-860, smaller volume is used . The objectives of the present study were to establish the frequency in which inadequate small blood volumes are employed for culturing and to analyze the relation between the cultured blood volume in Bactec 6A bottles and the yield achieved . MATERIAL AND METHODS: We weighed 2000 Bactec 6A bottles pertaining to consecutive blood cultures obtained from untreated patients with clinical suspicion of Infection . The cultured blood volume was estimated subtracting the mean empty bottle weight . RESULTS: Microorganisms were recovered from 251 bottles (12.5%) . One hundred and thirty one (6.8%) isolates were considered as clinically significant and 115 (5.7%) as contaminant . The inoculated blood volume in both significant (5.532 +/- 1.587 ml) and non-significant (5.471 +/- 1.563 ml) recoveries was superior than that of bottles without microbiologic growth (5.209 +/- 1.575 ml, p = 0.016 and p = 0.06, respectively) . A linear positive trend was found between the cultivated blood volume and the rate of recoveries (p = 0.008) . Within the range of 1 up to 10 ml, the rate of recoveries increased 2.28% for each additional ml of cultivated blood (r = 0.953, p < 0.0001) . Out of the 2,000 weighed bottles 127 (6.3%) contained less than 3 ml of blood and 576 (29%) between 3 and 5 ml . CONCLUSIONS: We have proved that the rate of recoveries from Bactec 6A bottles increased with the volume of cultured blood . In untreated patients, this increase is maintained up to volumes of 7 to 10 ml. J Mol Biol, 1997 Apr 11, 267(4), 841 - 8 Annealing of complementary DNA strands above the melting point of the duplex promoted by an archaeal protein; Guagliardi A et al.; One enigma in the biology of hyperthermophilic microorganisms, living near or above 100 degrees C, is how their genomes can be stable and, at the same time, plastic at temperatures above the melting point . The nonspecific DNA-binding protein Sso7d of the hyperthermophilic archaeon Sulfolobus solfataricus is known to protect DNA from thermal denaturation . We report here that Sso7d promotes the renaturation of complementary DNA strands at temperatures above the melting point of the duplex . This novel annealing activity is strictly homology-dependent, and even one mismatch in a stretch of 17 complementary bases severely reduces its efficiency . Since pairing of homologous single strands is a key step in all fundamental processes involving nucleic acids, such as transcription, replication, recombination, and repair, Sso7d is a candidate component of the protein machinery devoted to the coupling of DNA stability to metabolic flexibility at high temperature. FEBS Lett, 1997 Apr 7, 406(1-2), 23 - 7 Molecular characterization of PadA, a phenylacetaldehyde dehydrogenase from Escherichia coli; Ferrandez A et al.; The padA gene encoding the phenylacetaldehyde dehydrogenase involved in the catabolism of 2-phenylethylamine in Escherichia coli has been cloned, sequenced, and located at 31.0 min on the chromosome . The deduced PadA polypeptide contains 499 amino acid residues with a predicted molecular mass of 53.7 kDa, and its primary structure reveals significant similarity with that of members of the aldehyde dehydrogenase superfamily . By engineering optimal transcription and translation elements, a high expression of the padA gene has been achieved . The active PadA enzyme is a homodimer that prefers NAD+ over NADP+ as coenzyme . The enzyme efficiently oxidizes only phenylacetaldehyde-like aromatic aldehydes, and has a weak esterase activity with p-nitrophenol . The padA gene constitutes a new catabolic tool for designing DNA cassettes to expand the abilities of microorganisms to degrade toxic aromatic compounds. Mol Biotechnol, 1997 Apr, 7(2), 103 - 20 Quantification of the presence and activity of specific microorganisms in nature; Jansson JK et al.; Traditional techniques for assessment of microbial numbers and activity generally lack the specificity required for risk assessment following environmental release of genetically engineered microbial inocula . Immunological and molecular-based techniques, such as DNA probing and genetic tagging, were initially used to determine the presence or absence of microorganisms in environmental samples . Increasingly they are being developed for quantification of populations of specific organisms, either indigenous or introduced, in the environment . In addition, they are being used to quantify the activity of particular organisms or groups of organisms, greatly extending the range of techniques available to the microbial ecologist . This article reviews the use of traditional techniques for the quantification of microbial population size and activity and the application of molecular techniques, including DNA probing, genetic marking, use of fluorescent probes, and quantitative PCR, in combination with advanced cell detection techniques such as confocal laser scanning microscopy and flow cytometry. J Clin Pathol, 1997 Apr, 50(4), 278 - 82 Evaluation of a novel endoluminal brush method for in situ diagnosis of catheter related sepsis; Kite P et al.; AIMS: To determine the accuracy of a novel endoluminal brush method for the diagnosis of catheter related sepsis (CRS), which is performed in situ and hence does not require line sacrifice . METHODS: 230 central venous catheters in 216 patients were examined prospectively for evidence of CRS or colonisation using an endoluminal brush method in conjunction with peripheral blood cultures . The results were compared with those obtained using methods that require line sacrifice: extraluminal sampling (Maki roll) or endoluminal sampling (modified Cleri flush) of microorganisms . RESULTS: Only 16% of 128 patients suspected clinically of having line associated infection were confirmed as having CRS . In addition, 2 of 102 patients not suspected of having line associated infection had CRS . Line colonisation was apparent in approximately twice as many catheters using the Maki roll criteria (92%) compared with either the endoluminal brush (43%) or Cleri flush (43%) . Furthermore, colonised catheters sampled using the Maki roll technique yielded mixed growth twice as often as when examined by endoluminal methods (17 and 8 cases, respectively) . It was rare to detect either only endoluminal (4 of 22 episodes) or extraluminal (1 of 22 episodes) microorganisms in cases of CRS . In contrast, catheters defined as being colonised most frequently (59% of episodes) yielded only significant extraluminal growth . Only one case of CRS (5%) would have been "missed" if lines yielding a negative result from endoluminal brush sampling had been left in situ . Conversely, four episodes of CRS (18%) would not have been diagnosed by relying on extraluminal sampling alone . CONCLUSIONS: Diagnosis of CRS by the endoluminal brush method can be achieved without line sacrifice and is more sensitive (95%) and specific (84%) than extraluminal sampling of the catheter tip by the Maki roll technique (82% and 66%, respectively). Rev Mal Respir, 1997 Apr, 14(2), 93 - 9 {Hematopoietic growth factors and anti-infective respiratory defenses}; Gagnadoux F et al.; Colony-Stimulating Factors (CSFs) are a family of glycoproteins that are required for the proliferation and differentiation of hematopoietic progenitor cells . Among these factors, G-CSF and GM-CSF are principally involved in the production of neutrophils . They have been demonstrated to be effective in correcting neutropenia during cytotoxic chemotherapy or bone marrow transplantations . Beside their hematopoietic action, recent data indicate that G-CSF and GM-CSF also have stimulatory effects on mature neutrophils function . The functional properties of neutrophils that are enhanced by G-CSF and GM-CSF are those related primarily to the host's defense against microorganisms . For Gm-CSF those stimulatory effects also concern the macrophages . Investigations of several animal models of severe bacterial infection and specially pneumonia have indicated that exogenous recombinant G-CSF or GM-CSF can significantly enhance host defenses and improve rates of survival . Trials of recombinant G-CSF in combination with antibiotics for the treatment of severe pneumonia in noneutropenic patients have recently been initiated . First results confirm the good tolerance of recombinant G-CSF . Further prospective studies are required to determine the effectiveness and the conditions of administration of G-CSF and GM-CSF in this indication. Nutrition, 1997 Apr, 13(4 Suppl), 30S - 35S Prevention of catheter sepsis: the hub; Sitges-Serra A et al.; The prevention of catheter sepsis lies in a sound understanding of the routes through which catheters get contaminated . The catheter hub has been recognized as a portal for microorganisms causing catheter sepsis, particularly in central venous catheters inserted for > 1 wk . Bacteria and fungi may reach the internal surface of the catheter connector during manipulation by hospital staff and then colonize the entire lumen of the catheter . Endoluminal contamination has diagnostic, therapeutic, and preventive implications . Some traditional preventive approaches (site care, subcutaneous cuffs and tunnels, maximal aseptic barriers at the time of catheter insertion, and external antiseptic or antibiotic coating) may fail because they focus solely on the skin as a source of bacteria . Hub-related catheter sepsis can be prevented by aseptic hub manipulation, appropriate junction protection, and by reducing the number of catheter lumens, side ports, three-way stopcocks, and changes of the infusion sets . Needleless systems must be evaluated in terms of their safety in preventing endoluminal contamination . A new disinfecting catheter hub incorporating an antiseptic barrier has been developed and reduced hub-related catheter sepsis by more than 90% . The endoluminal route of intravascular catheter contamination must be taken into account when designing strategies for the diagnosis and prevention of catheter-related sepsis. Nutrition, 1997 Apr, 13(4 Suppl), 15S - 17S Relevance of the catheter hub as a portal for microorganisms causing catheter-related bloodstream infections; Salzman MB et al.; Microorganisms causing vascular catheter-related sepsis gain access to the bloodstream through either the skin at the catheter insertion site or through the catheter hub . The catheter insertion site is probably the predominant portal for microorganisms in catheters in place for a short time, but the catheter hub may play an increasingly important role in infection in association with long-term catheters, particularly those that are subcutaneously tunneled . Although transient contamination of the catheter hub does not cause infection, certain microorganisms may migrate endoluminally and enter the bloodstream, causing bacteremia or fungemia. FEMS Microbiol Rev, 1997 Apr, 19(4), 209 - 17 Coxiella burnetii: the 'query' fever bacterium . A model of immune subversion by a strictly intracellular microorganism; Mege JL et al.; Although substantial progress occurred in the knowledge of Coxiella burnetii during the past years, the pathophysiology of Q fever is still obscure . Emerging evidence from clinical investigations suggested that certain disorders of cell-mediated immunity play a pivotal role in Q fever and especially in its chronic form . This review analyses the potential strategies that C . burnetii, a strictly intracellular pathogen, use to divert microbicidal mechanisms of macrophages and to depress protective T-cell mediated immunity . The role of monocytes in the induction of Q fever is specifically discussed. J Biochem (Tokyo), 1997 Apr, 121(4), 717 - 23 Comparison of the gene expression of aspartate beta-D-semialdehyde dehydrogenase at elevated hydrostatic pressure in deep-sea bacteria; Kato C et al.; Aspartate beta-D-semialdehyde dehydrogenase genes (asd) were cloned and sequenced from a deep-sea-adapted strictly barophilic bacterium, Shewanella sp . strain DB6705, and a moderately barophilic bacterium, Shewanella sp . strain DSS12 . The determined asd sequences of these two strains were very similar, and the identity of the deduced amino acids sequences was 96.2% . The 5'-ends of the asd mRNA from both strains were localized at corresponding sites by primer extension analysis, and two transcriptional starting points, which differed by only 1 base, were detected . In strain DB6705, a pressure-regulated transcript was mainly observed, whereas in strain DSS12, a pressure-tolerant transcript was observed together with the pressure-regulated transcript . Western-blotting analysis showed that the ASD protein was expressed under higher pressure conditions in DB6705, and under all pressure conditions tested in DSS12, as reflected in the primer extension results . Our findings suggest that asd expression controlled by pressure is one of the important mechanisms involved in the adaptation of microorganisms to the deep-sea environment. J Clin Microbiol, 1997 Apr, 35(4), 999 - 1001 Severe keratitis due to Nocardia farcinica; Eggink CA et al.; Keratitis due to Nocardia farcinica occurred in a 49-year-old female after inappropriate cleaning of her semipermeable rigid contact lenses with basin-stored water during a holiday in France . N . farcinica was differentiated from Nocardia asteroides by its growth at 45 degrees C, acid production from rhamnose, its opacification of Middlebrook 7H10 agar, and its marked degree of resistance to all cephalosporins, aminoglycosides, tetracyclins, macrolides, and trimethoprim-sulfamethoxazole . To the best of our knowledge, this is the first reported case of human N . farcinica keratitis, confirming that this microorganism can be responsible for serious human disease. J Clin Microbiol, 1997 Apr, 35(4), 1024 - 6 Isolation of Lautropia mirabilis from sputa of a cystic fibrosis patient; Ben Dekhil SM et al.; An aggregate-forming coccus, isolated twice as the predominant microorganism in sputa from a cystic fibrosis patient on consecutive days, was shown to belong to the species Lautropia mirabilis on the bases of similarities of 16S rRNA gene sequences and phenotype . These isolates of L . mirabilis appear to be the first reported from a patient with cystic fibrosis and outside of Denmark. Nutr Clin Pract, 1997 Apr, 12(2), 68 - 71 Clinical management of latex allergy; Bey D et al.; The use of latex gloves in the health care setting dates back to the 1800s, when these products were introduced as a means of preventing the passage of microorganisms to operating room patients . Today, fear of human immunodeficiency virus transmission and other blood-borne diseases has led to implementation of standardized guidelines for glove use for health care professionals . Because of the unique combination of strength, flexibility, and elasticity of natural rubber, latex is typically the material of choice for a variety of medical products, including examination gloves . Unfortunately, routine use of latex in the health care setting may be detrimental to patients and caregivers with a history of natural rubber latex hypersensitivity reactions. Ann Occup Hyg, 1997 Apr, 41(2), 201 - 16 Exposure assessment of airborne microorganisms by fluorescence microscopy and image processing; Kildeso J et al.; The purpose of this study was to improve the exposure assessment of airborne microorganisms by means of image processing of fluorescence microscopy images . This technique reduces the analysis time and also offers the opportunity to measure the size distribution of the microorganisms . We developed and implemented an automatic focusing procedure in order to count and size evaluate the microorganisms in the sample . However, automatic focusing was not possible if there were any impurities such as larger particles present . Therefore, manual focusing of the microscope had to be applied in connection with automatic counting and size evaluation when assessing the exposure of workers handling materials containing microorganisms, for example . This is also an improvement as it is faster than the fully manual standard methods . The new methods developed in this study correlated (r2 > 0.85) with the standard method for samples of E . coli and for samples of generated airborne bioaerosols from household waste, although a correction factor is necessary . No correlation was found for samples of generated bioaerosols from composted waste . This work has established a possibility for improving exposure assessment of airborne microorganisms by means of image processing instead of manual counting. Glycobiology, 1997 Apr, 7(3), 445 - 51 Directed mutagenesis of the Trypanosoma cruzi trans-sialidase enzyme identifies two domains involved in its sialyltransferase activity; Smith LE et al.; Of the increasing number of sialidases found to be made by microorganisms, the trypanosome trans-sialidase is unique in its added ability to efficiently carry out a sialyltransferase reaction using preformed glycoconjugates . The enzyme is predicted to have a multidomain structure, with one domain containing sequence and expected structural features found in bacterial sialidases . The trans-sialidase is very similar in overall sequence to another trypanosome enzyme that has only sialidase activity . Hybrid expression constructs containing pieces of these trypanosome trans-sialidase and sialidase genes were used to determine which regions of trans-sialidase are required for sialyltransferase activity . Two domains were found to influence the enzymatic activity: the N-terminal catalytic domain, and a downstream domain that resembles an Fn3-like module. Biol Bull, 1997 Apr, 192(2), 253 - 61 Bacterial endosymbionts in the gills of the deep-sea wood-boring bivalves Xylophaga atlantica and Xylophaga washingtona; Distel DL et al.; Bacterial endosymbionts found in gill tissues in several bivalve families convert otherwise unavailable energy sources (sulfide, methane, or cellulose) to forms readily metabolized by their hosts . We investigated the existence of such a symbiosis in two species of Xylophaga (family Pholadidae) . The genus Xylophaga includes opportunistic species that are the predominant colonizers of wood at depths greater than 150 m . It has been hypothesized that, like their shallow-water counterparts the shipworms (family Teredinidae), species of Xylophaga utilize wood for nutrition . Results from transmission and scanning electron microscopy of X . atlantica and X . washingtona clearly demonstrate the presence of endosymbionts that resemble the shipworm endosymbionts both morphologically and in their anatomical location within the gills . Xylophaga and the teredinids both have a caecum packed with wood chips but lack the dense populations of microorganisms associated with cellulose digestion in termites or ruminants . These observations suggest that Xylophaga has evolved a symbiotic solution to wood digestion similar to that seen in shipworms . Hence, the Xylophaga symbiosis suggests a mechanism for the conversion of terrestrially derived cellulosic carbon from wood into animal biomass in the deep sea. J Clin Periodontol, 1997 Apr, 24(4), 237 - 48 Release and activation of human neutrophil matrix metallo- and serine proteinases during phagocytosis of Fusobacterium nucleatum, Porphyromonas gingivalis and Treponema denticola; Ding Y et al.; The phagocytic ingestion of reference strains and clinical isolates of Fusobacterium nucleatum, Porphyromonas gingivalis, and Treponema denticola by polymorphonuclear leukocytes (PMNs) and the concomitant release of PMN granule proteinases were studied by specific functional and immunological assays . PMNs were incubated with the microorganisms anaerobically at 37 degrees C for indicated time periods . The suspensions and pellets were used for phagocytic ingestion assay and electron microscopic study, respectively . The supernatants were used for the measurements of the amounts and activities of the released PMN enzymes including PMN gelatinase (MMP-9), collagenase (MMP-8), serine proteases (elastase and cathepsin G), and lactate dehydrogenase (LDH) . Both fluorescence microscopy and transmission electron microscopy showed that F . nucleatum, P . gingivalis and T . denticola were ingested by the PMNs in comparable numbers . However, measurements of the enzymes released from the triggered PMNs revealed major differences among the three species . High amount of elastase was released from the PMNs triggered by F . nucleatum, but not by P . gingivalis or T . denticola . The treatment of PMNs with P . gingivalis whole cells resulted in the release of gelatinase partly in the 82 kD active form, suggesting proteolytic activation of the degranulated 92 kD proMMP-9 . The 82 kD active form of gelatinase was not detected upon triggering the PMNs with F . nucleatum and T . denticola . The PMN-bacteria interaction did not result in release of LDH from triggered PMNs indicating the proteinase release was not due to the PMN cell death . The results show that the susceptibilities of the 3 potentially periodontopathogenic microorganisms, F . nucleatum, P . gingivalis and T . denticola to phagocytic ingestion are not directly related to the amounts and activities of PMN enzymes released during the bacteria-PMN interactions . As PMN degranulation is considered as one of the major pathogenic mechanisms in periodontitis, the observed differences among the microorganisms may be important virulence characteristics of these species. Intensive Care Med, 1997 Apr, 23(4), 476 - 9 Summary of round table conference: gut dysfunction in critical illness; Rombeau JL et al.; There is recent evidence that intestinal function is an important determinant in the outcome of critically ill patients . The barrier function is an important characteristic of the gut . Its workings are complex and it consists of epithelial, molecular, and immune components . The pathogenesis of gut dysfunction among critically ill patients is multifactorial, consisting of the quality and quantity of microorganisms, the permeability of the epithelium, and the extent of the vascular perfusion . A practical bedside measure of gut dysfunction is intolerance to enteral feedings . Potential therapies for gut dysfunction include the use of vasoactive drugs to enhance perfusion, selective decontamination to decrease bacteria and endotoxin, and the early and frequent administration of enteral nutrients. Int J Food Microbiol, 1997 Apr 1, 35(2), 163 - 8 Quality control of two rose bengal and modified DRBC and DG18 media; Olsen M et al.; The effect of storage on the performance of four mycological media, DG18, DRBC and two Rose Bengal agars, one from Difco, the other recommended by the Swedish Standard Institution, was investigated . The autoclaved media were stored (+4 degrees C) in the dark for up to 26 weeks . Following each storage period, the media were remelted and poured and the plates stored (+4 degrees C) in the dark for a maximum of 8 weeks before inoculation with test microorganisms . All media contained antibiotics . Both rapidly and slowly growing moulds, and also yeasts and bacteria were used as test microorganisms . No distinct effect of storage time on colony appearance could be shown for any of the four media . If the loss of restricted growth of Rhizopus stolonifer is used as a measure of the performance of the media, DRBC plates should not be stored for longer than 2 weeks after being poured from fresh medium . Storage of DRBC in flasks should not exceed 4 weeks and plates prepared from this medium should not be kept for more than 1 week . DG18 plates should only be poured from fresh medium and kept for a maximum of 1 week . The inhibitory effect of the antibiotic supplement on bacteria lasted for at least 4 weeks in DG18 and the two rose bengal media. Int J Food Microbiol, 1997 Apr 1, 35(2), 147 - 51 Heat resistance of Talaromyces flavus ascospores as determined by a two phase slug flow heat exchanger; Douglas King A; Heat resistance of Talaromyces flavus was determined using two methods . Standard thermal death time vials were used to determine the heat resistance of T . flavus ascospores, from 80 to 90 degrees C with a decimal reduction time D90 of 6.2 min . A continuous two-phase slug flow heat exchanger system with heating, holding and cooling sections was used to determine the heat resistance from 90 to 100 degrees C . Inoculated heating medium was pumped through 1.85 mm ID tubing in 'slugs' separated by air bubbles to interrupt laminar flow . Varying pump speed, length of tubing in the heating bath and temperature allowed collection of data under varied heating conditions . D90 with the slug flow heat exchanger system was 6.4 min, indicating the two methods were comparable, z values were 6.7 and 6.4 degrees C, respectively . The slug flow heat exchanger system permits rapid determination of heat resistance over a range of temperatures . Because of minimum come-up time the slug flow heat exchanger can be used at temperatures near the upper limit of heat resistance for the microorganism being tested. Clin Microbiol Rev, 1997 Apr, 10(2), 298 - 319 Leishmania and human immunodeficiency virus coinfection: the first 10 years; Alvar J et al.; Over 850 Leishmania-human immunodeficiency virus (HIV) coinfection cases have been recorded, the majority in Europe, where 7 to 17% of HIV-positive individuals with fever have amastigotes, suggesting that Leishmania-infected individuals without symptoms will express symptoms of leishmaniasis if they become immunosuppressed . However, there are indirect reasons and statistical data demonstrating that intravenous drug addiction plays a specific role in Leishmania infantum transmission: an anthroponotic cycle complementary to the zoonotic one has been suggested . Due to anergy in patients with coinfection, L . infantum dermotropic zymodemes are isolated from patient viscera and a higher L . infantum phenotypic variability is seen . Moreover, insect trypanosomatids that are currently considered nonpathogenic have been isolated from coinfected patients . HIV infection and Leishmania infection each induce important analogous immunological changes whose effects are multiplied if they occur concomitantly, such as a Th1-to-Th2 response switch; however, the consequences of the viral infection predominate . In fact, a large proportion of coinfected patients have no detectable anti-Leishmania antibodies . The microorganisms share target cells, and it has been demonstrated in vitro how L . infantum induces the expression of latent HIV-1 . Bone marrow culture is the most useful diagnostic technique, but it is invasive . Blood smears and culture are good alternatives . PCR, xenodiagnosis, and circulating-antigen detection are available only in specialized laboratories . The relationship with low levels of CD4+ cells conditions the clinical presentation and evolution of disease . Most patients have visceral leishmaniasis, but asymptomatic, cutaneous, mucocutaneous, diffuse cutaneous, and post-kala-azar dermal leishmaniasis can be produced by L . infantum . The digestive and respiratory tracts are frequently parasitized . The course of coinfection is marked by a high relapse rate . There is a lack of randomized prospective treatment trials; therefore, coinfected patients are treated by conventional regimens . Prophylactic therapy is suggested to be helpful in preventing relapses. J Bacteriol, 1997 Apr, 179(8), 2766 - 8 Unusual fatty acid compositions of the hyperthermophilic archaeon Pyrococcus furiosus and the bacterium Thermotoga maritima; Carballeira NM et al.; The fatty acid compositions of the hyperthermophilic microorganisms Thermotoga maritima and Pyrococcus furiosus were studied and compared . A total of 37 different fatty acids were identified in T . maritima, including the novel 13,14-dimethyloctacosanedioic acid . In contrast, a total of 18 different fatty acids were characterized, as minor components, in P . furiosus, and these included saturated, monounsaturated, and dicarboxylic acids . This is the first report of fatty acids from an archaeon. Nat Biotechnol, 1997 Apr, 15(4), 378 - 82 Bioprotection of microbial communities from toxic phenol mixtures by a genetically designed pseudomonad; Erb RW et al.; Pseudomonas sp . B13 SN45RE is a genetically engineered microorganism (GEM) that is able to simultaneously degrade mixtures of chloro- and methylaromatics ordinarily toxic for microbial communities via a designed novel ortho-cleavage pathway . The utility of the GEM was investigated in a laboratory scale sewage plant fed with mixtures of either 4-chlorophenol and 4-methyphenol or 3-chlorophenol and 4-methylphenol . In the model system the GEM significantly increased the rate and extent of degradation of the phenol mixtures . In the absence of the GEM, shock loads of the phenol mixtures (1 mM of each compound) reduced the numbers of culturable bacteria by three orders of magnitude, completely eliminated protozoa and metazoa, and caused a drastic decrease in oxygen consumption, whereas the presence of the GEM protected the indigenous microbial community and assured continued functioning of the sewage plant. Am J Ind Med, 1997 Apr, 31(4), 442 - 4 A meta-analysis of non-Hodgkin's lymphoma among farmers in the central United States; Keller-Byrne JE et al.; A meta-analysis of studies examining the association between non-Hodgkin's lymphoma (NHL) and employment as a farmer in the central United States was performed to verify the observation by Blair et al . {1993} that this group is at excess risk of NHL . Six studies were selected for the meta-analysis, and the estimator of relative risk calculated was 1.34 (95% confidence interval (CI) = 1.17, 1.55) . Exposures associated with NHL and associated with agricultural commodities frequently produced in the central United States are infectious microorganisms and pesticides . Examination of the production patterns of the farms in this region did not reveal a single specific risk factor consistently found on all farms; however, past production patterns suggest that exposure to either infectious microorganisms or pesticides might be a risk factor for NHL in this group of farmers. Steroids, 1997 Apr, 62(4), 332 - 45 Advances in microbial steroid biotransformation; Mahato SB et al.; Microbial biotransformations of various steroids are reviewed . Developmental studies on hydroxylation, carbon-carbon bond cleavage, enzymatic catalysis in nonaqueous solvents, use of cyclodextrin medium, cell immobilization, and new microbial reactions are highlighted . Various steroid substrates, their metabolites and the microorganisms used for the transformations are compiled covering the literature for the period 1992-1995. Pflugers Arch, 1997 Apr, 433(6), 832 - 41 Laser-assisted patch clamping: a methodology; Henriksen GH et al.; Laser microsurgery can be used to perform both cell biological manipulations, such as targeted cell ablation, and molecular genetic manipulations, such as genetic transformation and chromosome dissection . In this report, we describe a laser microsurgical method that can be used either to ablate single cells or to ablate a small area (1-3 microns diameter) of the extracellular matrix . In plants and microorganisms, the extracellular matrix consists of the cell wall . While conventional patch clamping of these cells, as well as of many animal cells, requires enzymatic digestion of the extracellular matrix, we illustrate that laser microsurgery of a portion of the wall enables patch clamp access to the plasma membrane of higher plant cells remaining situated in their tissue environment . What follows is a detailed description of the construction and use of an economical laser microsurgery system, including procedures for single cell and targeted cell wall ablation . This methodology will be of interest to scientists wishing to perform cellular or subcellular ablation with a high degree of accuracy, or wishing to study how the extracellular matrix affects ion channel function. Ugeskr Laeger, 1997 Mar 3, 159(10), 1417 - 22 {Pathogenic intestinal bacteria: adhesion and invasion}; Paerregaard A; Enteric bacterial pathogens cause considerable morbidity and mortality in developing countries . However, also industrialised countries are burdened with these microorganisms, and there is an increasing public awareness of the problems associated with foodborne diarrhoeal diseases . The ability to interact with the gut epithelium is essential for these bacteria . During the last 10-15 years our insight into the mechanisms for bacterial adhesion and invasion has increased dramatically, and, based upon this, new strategies for prevention and treatment of diarrhoeal diseases have been suggested . This review summarises the present general knowledge about bacterial adhesion and invasion in the gut and gives details for bacteria, that are recognised enteric pathogens . Examples are given about possible future use of this knowledge in the prevention or treatment of diarrhoeal disease. Curr Biol, 1997 Mar 1, 7(3), 176 - 83 Microfilament dynamics during cell movement and chemotaxis monitored using a GFP-actin fusion protein; Westphal M et al.; BACKGROUND: The microfilament system in the cortex of highly motile cells, such as neutrophils and cells of the eukaryotic microorganism Dictyostelium discoideum, is subject to rapid re-organization, both spontaneously and in response to external signals . In particular, actin polymerization induced by a gradient of chemoattractant leads to local accumulation of filamentous actin and protrusion of a 'leading edge' of the cell in the direction of the gradient . In order to study the dynamics of actin in these processes, actin was tagged at its amino terminus with green fluorescent protein (GFP) and observed with fluorescence microscopy in living cells of D . discoideum . RESULTS: Purified GFP-actin was capable of copolymerizing with actin . In the transfected cells of D . discoideum studied, GFP-actin made up 10-20% of the total actin . Microfilaments containing GFP-actin were capable of generating force with myosin in an in vitro assay . Observations of single living cells using fluorescence microscopy showed that the fusion protein was enriched in cell projections, including filopodia and leading edges, and that the fusion protein reflected the dynamics of the microfilament system in cells that were freely moving, being chemotactically stimulated, or aggregated . When confocal sections of fixed cells containing GFP-actin were labeled with fluorescent phalloidin, which binds only to filamentous actin, there was a correlation between the areas of GFP-actin and phalloidin fluorescence, but there were distinct sites in which GFP-actin was more prominent . CONCLUSIONS: Double labeling with GFP-actin and other probes provides an indication of the various states of actin in motile cells . A major portion of the actin assemblies visualized using GFP-actin are networks or bundles of filamentous actin . Other clusters of GFP-actin might represent stores of monomeric actin in the form of complexes with actin-sequestering proteins. Mikrobiol Z, 1997 Mar-Apr, 59(2), 96 - 105 {Microphytic algae in the pathology of the cetaceans}; Birkun AA Jr et al.; The review includes the analysis of the world literature (1913-1995) about the problems of interrelations, between microorganisms (microphytic algae and cyanobacteria) and marine mammals (whales and dolphins) . Special attention is payed to the parasitological, bioindicative and toxicological aspects of microalgae inhabiting the surface of the skin integuments and respiratory organs of cetaceans, as well as their environment . There is the list of the algal species overgrowing the animals bodies and their hosts . The most of the epibionts are belonging to diatoms, there are also some cyanobacteria and green algae . The probability of the influence of the algological factor on the hosts health and a possibility of the microalgae use to evaluate the status of animals and their environment have been discussed. Mikrobiol Z, 1997 Mar-Apr, 59(2), 3 - 11 Antisignature oligonucleotides and their analogs as inhibitors of mollicutes-cofactors of HIV; Skrypal' IH et al.; Inhibition of mollicutes by synthetic oligonucleotides and their analogs complementary to specific "signature" regions of 16S rRNA and corresponding sequences of ribosomal operon DNA was studied . It was shown that antisignature oligonucleotides inhibited transcription in vitro for above 79% interacting specifically with ribosomal operon and non-specific with DNA-dependent RNA-polymerase . The inhibition efficiency depended on oligonucleotide sequence and type of modification . Translation in vitro was suppressed most efficiently (up to 60%) by oligonucleotides complementary to 3'-end region of 16S rRNA, also depending on their modification . Translation in vivo was inhibited most efficiently (up to 73%) by thiophosphate analogs of oligonucleotides complementary to sequences 499-507 and 523-532 of 16S rRNA responsible for binding of ribosomal "core" protein S4 starting the assembly of 30S ribosome subunit . With the simultaneous use of the last two oligonucleotides, the growth of mollicutes in SM IMV-72 medium rich in exogenous sources of nucleosides was suppressed for over 90% . It is supposed that under conditions where mollicutes have no free access to starting materials for their own synthesis of nucleic acid these nucleotides could suppress microorganisms completely . Antisignature oligonucleotides are considered as superspecific agents not leading to the development of resistance of mollicutes and believed to be the main future remedy against diseased caused by microorganisms lacking the system of nucleoside synthesis. Drug Metab Dispos, 1997 Mar, 25(3), 311 - 6 Microbial models of mammalian metabolism . Fungal metabolism of phenolic and nonphenolic p-cymene-related drugs and prodrugs . II . Metabolites of nonphenolic derivatives; Moussa C et al.; A cymene-derived drug, 3-{4'-(o-ethoxyphenyl)piperazin-1'-yl}-ethyloxy-p-cymene+ ++ (B1178), is not significantly metabolized by fungal microorganisms . On the contrary, one of its metabolites in rat, 3-(piperazin-1'-yl)ethoxy-p-cymene (B1071), is quantitatively converted by Cunninghamella echinulata NRRL 3655 into two hydroxylated products: the corresponding phenol derivative and a benzylic alcohol derivative . Other strains, such as Beauveria bassiana ATCC 7159 and Mortierella isabellina MMP 108, produce exclusively an N-acetyl derivative in high yield . Results obtained are discussed on the grounds of relative hydrophobicity of substrates vs . fungi metabolism and detoxification capabilities. Nutr Rev, 1997 Mar, 55(3), 65 - 75 Microorganisms as an alternative source of protein; Kuhad RC et al.; Demand for human food and animal feed proteins from nonconventional sources has increased, particularly in developing countries . Microbial protein is one such source . It is desirable because it is amenable to controlled intensive cultivation and is less dependent on variations in climate, weather, and soil . Microbial proteins must be evaluated for nutritive value, safety, and economic considerations before mass production is undertaken. Epidemiol Mikrobiol Imunol, 1997 Mar, 46(1), 9 - 12 {Detection of DNA specific for Mycobacterium tuberculosis in archeological material using the polymerase chain reaction}; Horvath R et al.; The paleopathological diagnosis of bone tuberculosis in archeological findings may be confirmed by the polymerase chain reaction (PCR) . If the M . tuberculosis-specific DNA fragment is amplified, then the presence of this microorganism in the sample is demonstrated . The pilot study presented investigated whether our molecular biology laboratory can collaborate with anthropologists in paleopathological analyses and to verify the use of the commercial diagnostic kit Cleanmix (Talent, Italy), for DNA isolation from archeological samples . The results were compared with the conclusions of anthropologists . Successful amplification of specific DNA fragments was achieved in a specimen from the period of the 13th to 15th century . The specimen consists of four thoracic vertebrae modified by osseous tuberculosis (gibbus) . The PCR result was also positive in a five-year-old femur sample of a patient with chronic pulmonary tuberculosis . All other specimens of various ages but without macroscopic symptoms of osseous tuberculosis, were PCR negative . These results suggest that it is possible to detect former infections with pathogenic microorganisms in archeological bones find. Ann Periodontol, 1997 Mar, 2(1), 199 - 212 The design and implementation of trials of host modulation agents; Offenbacher S et al.; Over the last two decades it has become more evident that although oral microorganisms are essential agents of periodontal pathogenesis, interpatient variability in the host response is a major determinant of the expression of periodontal disease extent and severity . Data from animal models and human studies have identified many of the components of the host inflammatory response which serve as critical mediators of clinical inflammation, attachment loss, and bone resorption . Studies suggest that certain pharmacologic agents, which act at a molecular level to block specific inflammatory mediators, appear to attenuate disease progression . These promising findings herald a new era in periodontal medicine . Anti-infective therapies may soon be supplemented with anti-inflammatory pharmacological agents . However, there are many unanswered issues regarding formulation design, clinical application, potential indication claims, and clinical study design . Furthermore, current considerations of fundamental mechanisms of pathogenesis, as well as new data from epidemiologic studies emphasizing the multifactorial nature of disease, are changing the underlying assumptions which have served to guide our design of anti-infective drug trials over the last two decades . There are new questions regarding appropriate outcome measurements which are to be reconsidered . For example, the measurement of a change in periodontal disease status, either during progression or in response to therapy, is fundamentally unidimensional and may be only mildly informative when one considers that the disease is multifactorial by nature . Using an example from intensive care medicine, pathophysiologic studies of septic shock have demonstrated that the microbial dose and the host inflammatory mediator response are far better predictors of patient morbidity and mortality than any combination of clinical signs associated with clinical shock . Clinical trials of anti-cytokine and anti-inflammatory drugs to treat shock are now designed and conducted taking strategic advantage of this knowledge by including measurements of microbial dose and host response . It appears prudent that the design and implementation of clinical trials of host modulation agents also benefit from our current insights into pathogenesis and not represent a template-driven adaptation of historical, anti-infective clinical trial protocols. Electrophoresis, 1997 Mar-Apr, 18(3-4), 491 - 7 The Dictyostelium discoideum proteome--the SWISS-2DPAGE database of the multicellular aggregate (slug); Yan JX et al.; The cellular slime mold Dictyostelium discoideum is a eukaryotic microorganism which has developmental life stages attractive to the cell and molecular biologist . By displaying the two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) protein map of different developmental stages, the key molecules can be identified and characterised, allowing a detailed understanding of the D . discoideum proteome . Here we describe the preparation of reference gel of the D . discoideum multicellular aggregate, the slug . Proteins were separated by 2-D PAGE with immobilised pH gradients (pH 3.5-10) in the first dimension and sodium dodecyl sulfate (SDS)-PAGE in the second dimension . Micropreparative gels were electroblotted onto polyvinylidene difluoride (PVDF) membranes and 150 spots were visualised by amido black staining . Protein spots were excised and 31 were putatively identified by matching their amino acid composition, estimated isoelectric point (pI) and molecular weight (M(r)) against the SWISS-PROT database with the ExPASy AAcompID tool . A total of 25 proteins were identified by matching against database entries for D . discoideum, and another six by cross-species matching against database entries for Saccharomyces cerevisiae proteins . This map will be available in the SWISS-2DPAGE database. Clin Lab Med, 1997 Mar, 17(1), 1 - 19 Quantification of nucleic acids; Killeen AA; Quantification of nucleic acids is an area of growing importance in the clinical laboratory . In addition to routine measurements of total nucleic acid concentrations, quantitative techniques are used to determine the number of microorganisms in samples, the level of expression of genes, or the presence of alterations in gene dosage . This article provides an overview of current methodologies for measurement of total and specific nucleic acid concentrations. Schweiz Med Wochenschr, 1997 Mar 1, 127(9), 360 - 6 {Susceptibility to infection}; Cerny A; Recurrent infections in individual patients prompt concern regarding an underlying immunodeficiency . It is often difficult to make a distinction between "normal" and abnormally frequent occurrence of infections . Infectious diseases are the result of a series of complicated interactions between host factors, pathogen properties and epidemiological circumstances . This paper reviews the role of non-specific and antigen-specific host factors relevant to the management of a patient with suspected immunodeficiency . The most important effector mechanisms of immune defence are outlined and the consequences of their failure with respect to specific infections are discussed . Analysis of the clinical presentation, pathophysiology and microorganisms involved offers clues as to which part of the immune system is failing in an individual patient . Based on this, further tests will confirm or exclude an underlying immunodeficiency . The paper concludes with an overview of relevant therapeutic and prophylactic options. Eur J Clin Microbiol Infect Dis, 1997 Mar, 16(3), 210 - 3 Novel approach to investigate a source of microbial contamination of central venous catheters; Elliott TS et al.; The potential route of contamination by skin microorganisms onto the distal tip of central venous catheters during insertion was investigated . Thirty patients undergoing cardiac surgery who required a central venous catheter (CVC) as part of their clinical management were studied . Following catheter placement, the device insertion equipment and the skin at the insertion site were sampled for microorganisms . The distal tips of the CVCs were also sampled in situ within 90 min post insertion . Bacteria were isolated from 20 of 30 (66%) CVC skin insertion sites, from 15 of 30 (50%) guidewires, and from five of 30 (16%) catheter distal tips in situ . These findings suggest that despite rigorous skin disinfection and strict aseptic technique, viable microorganisms are impacted during insertion onto the distal tip of the CVC, which may act as a subsequent nidus of infection. Eur J Clin Microbiol Infect Dis, 1997 Mar, 16(3), 189 - 201 Overview of the etiology of wound infections with particular emphasis on community-acquired illnesses; Janda JM et al.; Wound cultures represent a general catchall category for a group of extremely diverse anatomic samples that range from superficial specimens of cutaneous structures (folliculitis, cellulitis) to specimens revealing invasive infections involving deep fascial planes and muscle (myonecrosis) . Because of the complex nature of these infective processes, the terminology associated with such infections is often imprecise and confusing . Wounds are the result of trauma, either intentionally or accidentally induced . Nosocomial wound infections result primarily from surgical procedures, the development of pressure sores, or catheterization . Community-acquired wound infections are often preceded by injuries resulting from occupational exposure or recreational activities and are associated with a greater diversity of microorganisms due to the exposure of open wounds to inhabitants of the microbial biosphere . This review provides a general overview of the categories of wound infections and describes their acquisition and clinical significance . Particular emphasis is placed on selected community-acquired wound infections and the etiologic agents associated with such conditions. J Med Microbiol, 1997 Mar, 46(3), 188 - 94 The possibilities and limitations of nucleic acid amplification technology in diagnostic microbiology; Vaneechoutte M et al.; Nucleic acid amplification technology is examined from the critical viewpoint of a clinical microbiologist working in a routine diagnostic bacteriology laboratory . Widely recognised limitations of amplification technology include those of false-positive and false-negative results, the difficulty of obtaining quantitative results, the problem of using this technology for susceptibility testing, and the difficulty of detecting routinely the wide range of possible pathogens contained in a clinical sample . On the positive side, amplification technology brings welcome new possibilities for rapid detection of specific pathogens in a sample, including viruses, slowly growing bacteria, fastidious or uncultivable bacteria, fungi and protozoa . Other possible applications include screening normally sterile clinical samples for non-specific bacterial contamination and the use of amplification-based DNA fingerprinting methods for identification and typing of microorganisms . Nevertheless, it is predicted that-in contrast to research and reference facilities-routine bacteriology laboratories will continue to rely on culture as the preferred 'amplification method' for most diagnostic applications. Ecotoxicol Environ Saf, 1997 Mar, 36(2), 140 - 7 Evidence from whole-sediment, porewater, and elutriate testing in toxicity assessment of contaminated sediments; Liss W et al.; Bioassays with microorganisms are widely used as tools in estimating the potential risk of contaminated sediments . Although whole-sediment testing seems the most realistic approach to evaluate the bioavailability of contaminants in sediments, porewaters and aqueous extracts are frequently used . The object of this study was to compare whole sediment, porewater, and elutriate exposure of contaminated sediment simultaneously with two bacterial bioassays . Artificial sediment was spiked with five chemicals of different chemical and physical properties as single substances and as a mixture of all substances . Depending on the quality of the toxicants the test organisms were affected via aqueous phase (elutriate or porewater) or via solid phase (whole sediment) . Sediment quality criteria based on the distribution of chemicals between sediment and aqueous phase and assessment of the toxicity of a sediment with water quality criteria were not confirmed by this study . The DHA solid-phase assay illustrated that threshold concentrations based on the NOEC values of single chemicals are not always sufficient to assess the risk of polluted sediments for organisms . It is suggested that for the evaluation of the potential hazard of a sediment contaminated with an unknown mixture of chemicals all exposure routes of contaminants should be examined by elutriate, porewater, and whole-sediment testing. Presse Med, 1997 Mar, 26 Suppl 2, 11 - 5 {Intracellular penetration of macrolides}; Labro MT; CELL PENETRATION: One of the main features of macrolides is their capacity to penetrate host cells . This property is the basis of their action against intercellular microorganisms and can explain characteristic pharmacokinetics as well as interference with cell metabolism . INTRACELLULAR CONCENTRATION: Erythromycin A derivatives with a single base group (roxithromycin) accumulate rapidly to a saturation point both the cytoplasm and in granulations . Intracellular concentrations of derivatives with two base groups do not reach saturation due to slow exflux . THERAPEUTIC ACTION: Because of their intracellular concentration, macrolides are indicated for the treatment of cell-associated pathogens . Exflux allows possible selective transfer into infected tissues . Macrolides also have an effect on functional activity of the host cells. Clin Neuropathol, 1997 Mar-Apr, 16(2), 55 - 60 Neuro-Behçet's disease; Hadfield MG et al.; We are reporting a case of Bechcet's disease without vasculitis but with acute neutrophilic inflammation which involved the brain and other organs . The patient exhibited waxing and waning neurological deficits which were unresponsive to treatment . The neuroradiologic findings simulated those of multiple sclerosis . The neuropathological examination revealed an acute, focal, though disseminated encephalitis involving the frontal lobe, internal capsule, basal ganglia, cerebellum, and brainstem . The acute inflammation consisted of a neutrophilic and eosinophilic infiltration of the perivascular spaces and parenchyma without evidence of vasculitis, fibrinoid necrosis, or thrombosis . Cultures and special stains for microbial organisms were negative . Ultrastructural examination revealed no viral structures or other microorganisms . In situ hybridization for Epstein-Barr virus (EBV), herpes simplex virus type I (HSV-I), and cytomegalovirus (CMV) was negative . In this case, the lack of inflammation in the vessel walls points out that the necrotizing lesions in neuro-Bechcet's disease need not be the result of vasculitis and superimposed thrombosis, but may occur as a result of primary, acute neutrophilic inflammation. J Periodontol, 1997 Mar, 68(3), 249 - 55 Inflammatory and immune mediators in crevicular fluid from HIV-infected injecting drug users; Grbic JT et al.; Gingival crevicular fluid (GCF) levels of the polymorphonuclear leukocyte (PMN) lysosomal enzyme beta-glucuronidase (beta G), the pro-inflammatory cytokine interleukin 1 beta (IL-1 beta), and immunoglobulins (IgA, IgG, and IgM) were examined in 16 HIV seropositive (HIV+) and 10 HIV seronegative (HIV-) injecting drug users (IDU) . Each subject received a periodontal examination including assessment of probing depth, attachment level, bleeding on probing, and plaque and calculus accumulation . GCF was collected from the mesial surfaces of premolar and molar teeth using filter paper strips . Although HIV+ subjects had a significantly lower number of peripheral blood CD4+ T cells/mm3 compared to HIV- subjects, there were no significant differences in mean probing depth, percentage of sites exhibiting bleeding on probing, or plaque and calculus accumulation between HIV- and HIV+ subjects . When the GCF components were analyzed, we found no significant differences between HIV- and HIV+ subjects in GCF levels of beta G, IL-1 beta, IgA or IgM, but GCF levels of IgG were significantly increased in HIV+ subjects . When sites were categorized by probing depth, no differences in the levels of beta G, IgA, IgG, and IgM existed between sites with probing depth < or = 3 mm compared to sites with probing depth > or = 4 mm in both HIV- and HIV+ IDU . However, levels of IL-1 beta in GCF were increased in the deeper sites (> or = 4 mm) in HIV+ IDU when compared to sites with PD < or = 3 mm . Analyzing GCF constituents in relation to the CD4 cell number, no differences were found between subjects with < or = 400 or > 400 CD4 cells/mm3 with respect to the levels of IL-1 beta, IgG, and IgM . However, the level beta G was significantly decreased in the HIV+ IDU with < or = 400 CD4 cells when compared to those with > 400 CD4 cells/mm3, while levels of IgA were significantly higher in HIV+ subjects with < or = 400 CD4 cells/mm3 . Our results suggest that levels of IgG, and in immunodeficient subjects IgA were increased in GCF of HIV+ IDU while decreased levels of beta G were found in immunodeficient HIV+ IDU . These findings may be local manifestations of systemic alterations and suggest that analysis of GCF may provide insight into the immune and inflammatory responses of HIV-infected individuals to periodontal microorganisms. Biochem Mol Biol Int, 1997 Mar, 41(3), 575 - 81 Mössbauer spectroscopic study of the interaction of indole-3-acetic acid with iron(III) in aqueous solution; Kamnev AA et al.; The data of Mossbauer spectroscopic measurements in rapidly frozen 57FeIII nitrate solutions containing indole-3-acetic acid (IAA) are presented . The results obtained provide direct evidence that iron(III) is gradually reduced by IAA with the formation of soluble iron(II) complex . It has been found that further drying of the solution in air results in complete re-oxidation of iron(II) with the formation of iron(III) complex . The structure of the complexes obtained and their possible role in solubilization and transformation of iron species in soil in the presence of IAA secreted by soil microorganisms into the environment are also discussed. Pediatr Pathol Lab Med, 1997 Mar-Apr, 17(2), 171 - 208 Gastrointestinal manifestations in pediatric AIDS; Kahn E; The pathologic changes in the gastrointestinal tract of children with AIDS are variable, clinically significant, and reflect multisystemic disease processes . Inflammation, changes in the lymphoid tissue, miscellaneous lesions, and tumors are documented in 58 patients in addition to cases reported in the literature . Cytomegalovirus infection of the gastrointestinal tract, associated with ulcerations, hemorrhage, perforations, and intestinal obstruction, carries a high morbidity and mortality, whereas the remaining infections are not life threatening . Special stains and electron micrographic examination are important to identify correctly certain microorganisms such as mycobacterium avium intracellulare, cryptosporidia, and microsporidia . Lymphoproliferative changes of the gastrointestinal tract, a component of the generalized lymphoproliferative process, need to be characterized by tumor markers and cytogenetic studies . Within the miscellaneous lesions, AIDS associated arteriopathy can be complicated by intestinal ulceration and perforation . Both lymphomas and smooth muscle tumor in children with AIDS are related to Epstein-Barr virus infection . The smooth muscle tumors are frequently malignant and multiple. Trends Microbiol, 1997 Mar, 5(3), 109 - 14 Interactions between enteropathogenic Escherichia coli and host epithelial cells; Donnenberg MS et al.; The pathogenesis of enteropathogenic Escherichia coli (EPEC) infection is emerging as a paradigm for a multistage microorganism-host cell interaction . Both type IV fimbriae and a type III secretion apparatus play principal roles in interactions between the bacteria and host cells . Recent data suggest that bacteria-induced signal transduction activates the receptor that allows tenacious adherence of the bacteria to the host cell surface. Arch Otolaryngol Head Neck Surg, 1997 Mar, 123(3), 253 - 6 Otorhinolaryngologic computer-assisted biopsies of the Iceman; Gunkel AR et al.; BACKGROUND: The Iceman is a prehistoric, completely preserved, 5300-year-old male human mummy . OBJECTIVE: To obtain the first biopsy specimens from inside the Iceman while meeting an extended standard of hygiene and following precise intraoperative guidance to the site of biopsy and keeping tissue damage to a minimum . DESIGN: Biopsy specimens from the nose, the maxillary sinus, and the larynx of the Iceman were obtained . Special caution had to be taken while performing the biopsies to not contaminate the Iceman with heavy metals or remnants of microorganisms . SUBJECT: The Iceman, a cadaver kept frozen in a glacier for 5300 years . The Iceman is in an excellent state of preservation and will allow fundamental histological, morphological, and molecular genetic insights into early man . INTERVENTION: The biopsies were planned and executed with the aid of Interventional Video Tomography, a system that guides the surgeon to the target area by combining live video with existing imaging modalities . The system does not need mechanical fixation of the subject (the Iceman) and is barely in physical contact with the subject; thus, it was the ideal tool for guiding the surgeon to the site of the biopsy samplings through a tiny canal into the nose, the maxillary sinus, and the larynx of the Iceman . RESULTS: We have obtained a number of tissue samples by precisely guided 3-dimensional navigation . Unnecessary tissue damage was avoided . CONCLUSIONS: Visual inspection of the extracted mucosa showed typical human cadaver tissue, despite its age, without clinical abnormalities . Currently, the samples are being investigated by various international scientific groups. Cell Biochem Funct, 1997 Mar, 15(1), 35 - 8 Decreased cell surface charge in cystic fibrosis epithelia; Thethi K et al.; A colloid titration technique has been used to determine the surface charge of cystic fibrosis (CF) and corresponding non-CF epithelial cells . We have shown that the negative surface charge of CF epithelial cells is significantly reduced in comparison with non-CF cells . This fact may play an important role in CF, where the increased adherence of microorganisms is known to cause chronic lung infection . Neuraminidase treatment removed approximately the same amount of surface charge in both cell lines, indicating no differences in cell surface sialylation . Similar results were obtained by direct measurements of the amount of N-acetylneuraminic acid released by neuraminidase . Therefore, our results indicate that sialic acid residues are not involved in the reduction of the negative surface charge in CF . This conclusion does not support the hypothesis that undersialylation of cell-membrane molecules occurs in cystic fibrosis. Clin Exp Immunol, 1997 Mar, 107(3), 468 - 73 CD4+ T cell-mediated fatal hyperinflammatory reactions in mice infected with Penicillium marneffei; Kudeken N et al.; In the present study, we demonstrate that all mice survived when a low dose of Penicillium marneffei was instilled intratracheally, while severe infection induced by instillation of 1 x 10(8) and 1 x 10(7) colony-forming units (CFU) killed all and 50% of mice, respectively, within 14 days, although the number of live microorganisms in the lungs of these animals was found to decrease with time . The cellular inflammatory responses in the lungs were much more striking in mice with severe infection than in animals infected with a low dose of microorganisms . The number of leucocytes, macrophages, neutrophils and lymphocytes in the lungs increased progressively during infection, and were more than 50 times higher on day 11 than in the control count . CD4+ T cells were the predominant cells in the lungs, and played an important role in hyperinflammatory host reactions, because neutralizing anti-CD4 MoAb increased the survival rate in infected mice despite the presence of a high number of live microorganisms in the lungs . Our results indicate that severe infection with P . marneffei induces fatal hyperinflammatory host reactions, mediated to a large extent by CD4+ T cells, although the infection is well controlled . However, the contribution of endogenous tumour necrosis factor-alpha (TNF-alpha) remains unsubstantiated, since administration of neutralizing anti-TNF-alpha MoAb in the present study failed to prolong survival in infected mice. J Leukoc Biol, 1997 Mar, 61(3), 293 - 302 Secretion and inactivation of myeloperoxidase by isolated neutrophils; King CC et al.; Neutrophils prevent infection by ingesting and killing microorganisms but oxidants and proteases released by neutrophils damage host tissues . Our aim was to identify factors that regulate oxidant production by the enzyme myeloperoxidase (MPO) following secretion of MPO into the medium . Cells stimulated with phorbol myristate acetate (PMA) or opsonized zymosan particles secreted MPO and released superoxide free radicals (.O2-) . Dismutation of .O2- produced hydrogen peroxide (H2O2) and MPO catalyzed the oxidation of chloride ion by H2O2 to produce the toxic oxidant hypochlorous acid (HOCl) . Adding the enzyme superoxide dismutase (SOD) to increase the rate of conversion of .O2- to H2O2 had pH-dependent effects on HOCl production . From pH 6.0 to 7.4, SOD promoted HOCl production by up to 500% but SOD had no effect at pH 7.6 and inhibited by 40 +/- 10% at pH 7.8 . In further experiments at pH 7.0, MPO activity in the cells decreased by 25 +/- 2 and 44 +/- 4% during 1-h incubations with PMA and zymosan . Only 1 +/- 0 and 3 +/- 1% of the total activity was found in the medium, indicating that most of the secreted MPO was inactivated . Loss of activity was not accompanied by proteolytic destruction of the MPO protein, which was measured with anti-MPO antibodies . SOD raised the amount of active MPO in the medium two- to sevenfold, but adding deferoxamine to chelate iron or adding ferric ion had no effect . The ionophore A23187 was as effective as zymosan as a stimulus for MPO secretion but .O2- production by ionophore-stimulated cells was less than 4% of that of PMA- or zymosan-stimulated cells and most of the secreted MPO was found active in the medium . When PMA-stimulated cells were incubated with purified MPO, the added MPO activity was lost from the medium . Binding or proteolysis did not account for loss of activity as indicated by recovery of added radioiodinated MPO from the medium . The visible absorption spectrum of MPO was lost, indicating destruction of the iron-containing prosthetic group . Loss of activity and loss of the MPO spectrum were blocked by SOD but not by deferoxamine or catalase . The results indicate that, in the physiological pH range, inactivation of MPO in the medium suppressed HOCl production . Inactivation required O2- but not HOCl, H2O2, or free iron . Inactivation of secreted MPO may limit MPO-mediated damage to host tissues by stimulated neutrophils. J Neuroimmunol, 1997 Mar, 73(1-2), 7 - 14 Identification of an epitope derived from human proteolipid protein that can induce autoreactive CD8+ cytotoxic T lymphocytes restricted by HLA-A3: evidence for cross-reactivity with an environmental microorganism; Honma K et al.; The demyelination process that occurs in the central nervous system (CNS) of patients with multiple sclerosis (MS) is in part due to an inflammatory response in which CD4+ and CD8+ T cells and macrophages infiltrate white matter . In this study, we have identified a peptide sequence derived from the CNS-specific myelin protein proteolipid protein (PLP) which could bind to HLA-A3 and induce a HLA-A3-restricted CD8+ CTL response from HLA-A3+ donors . These PLP peptide-specific CTL could lyse HLA-A3+ target cells pulsed with a homologous peptide derived from the CRM1 protein of Saccharomyces cerevisae . These findings demonstrate the immunogenic potential of a PLP-derived peptide for generation of autoreactive HLA-A3-restricted CD8+ CTL, and further show that these CTL can be activated by a peptide derived from a common environmental microorganism. Appl Environ Microbiol, 1997 Mar, 63(3), 1028 - 33 A simple method for quantification of uncultured microorganisms in the environment based on in vitro transcription of 16S rRNA; Polz MF et al.; A simple method for the quantification of uncultured microorganisms in the environment was developed . In vitro-transcribed 16S rRNA is used as a template for midpoint dissociation temperature (Td) determinations of specific oligonucleotide probes and as a standard in quantitative probing . It replaces the need for total nucleic acids extracted from pure cultures of the organisms to be quantified . A sense RNA of a size almost identical to that of native 16S rRNA can be transcribed from ribosomal DNA clones recovered in studies of the phylogenetic diversity of microbial communities . This in vitro-transcribed rRNA yields dissociation curves typical of oligonucleotides . They parallel curves determined with total nucleic acids but yield slightly higher Td values . Neither unspecific sticking of the probe nor probe washing off the DNA template at low temperatures fully accounted for the discrepancy in probe release from the two templates . This suggests that the native rRNA itself has melting characteristics different from those of its in vitro-transcribed counterpart . However, this difference does not affect the performance of in vitro-transcribed rRNA compared with total nucleic acids as a standard in quantitative hybridizations . No difference was found between the estimates of the relative quantity of a single bacterial species in a mixed community obtained with the two standards, regardless of whether DNA was removed from the samples . This protocol will allow the large-scale quantification of the ecological importance of uncultured microorganisms in natural environments for the first time. Proc R Soc Lond B Biol Sci, 1997 Feb 22, 264(1379), 245 - 51 Contrasting levels of variability between cytoplasmic genomes and incompatibility types in the mosquito Culex pipiens; Guillemaud T et al.; Reproductive incompatibilities called cytoplasmic incompatibilities are known to affect a large number of arthropod species and are mediated by Wolbachia, a maternally transmitted microorganism . The crossing relationships between strains of potential hosts define their incompatibility types and it is generally assumed that differences between strains of Wolbachia induce different crossing types . Among all the described host species, the mosquito, Culex pipiens, displays the greatest variability of cytoplasmic incompatibility crossing types . We analysed mitochondrial and bacterial DNA variability in Culex pipiens in order to investigate some possible causes of incompatibility crossing type variability . We sequenced fragments of the ftsZ gene, and the A + T-rich control region of the mtDNA . We also sequenced the second subunit of the mitochondrial cytochrome oxidase (COII) gene, in Culex pipiens and a closely related species, C . torrentium, in order to verify the usefulness of the A + T-rich region for the present purposes . No variability was found in the Wolbachia ftsZ gene fragment, and very limited variation of the mitochondrial marker whatever the compatibility type or the origin of the host . A low variability was found in the A + T-rich region and comparison of divergence of the A + T-rich region and COII gene between C . pipiens and C . torrentium did not reveal any special constraints affecting this region . In contrast to observations in other host species, variability of incompatibility crossing types is not due to multiple infections by distantly related Wolbachia strains. J Biol Chem, 1997 Feb 21, 272(8), 4935 - 40 Roles of hydrogen bonding residues in the interaction between the alpha and beta subunits in the tryptophan synthase complex . Asn-104 of the alpha subunit is especially important; Hiraga K et al.; The interaction of the alpha subunit with the beta2 subunit of tryptophan synthase is known to be necessary for the activation of each subunit and for the catalytic efficiency of the alpha2beta2 complex . To elucidate the roles of hydrogen bonds in the interaction site between the alpha and beta subunits for subunit association, eight mutant alpha subunits at five hydrogen bonding residues (N104D, N104A, N108D, N108A, E134A, E135A, N157D, and N157A) were constructed, and the thermodynamic parameters of association with the beta subunit were obtained using a titration calorimeter . The N104D and N104A mutations remarkably decreased the stimulation activities, the association constants, and the association enthalpies . Although the association constant and the stimulation activities of E134A were reduced in the absence of salt, the change in the association enthalpy was relatively small, and the addition of salt could repair its defects . The substitutions at positions 135 and 157 did not affect the stimulation activity and decreased the Gibbs energy of association corresponding to the defect in 1 mol of hydrogen bond . The present results suggest that the alpha subunit which has a mutation at position 104 cannot fold into an intact conformation upon complex formation, resulting in reduced stimulation activities . The hydrogen bond with Asn-104, which is a conserved residue among 16 microorganisms, was especially important for alpha/beta interaction and mutual activation. Gene, 1997 Feb 20, 186(1), 135 - 42 Minilibraries constructed from cDNA generated by arbitrarily primed RT-PCR: an alternative to normalized libraries for the generation of ESTs from nanogram quantities of mRNA; Neto ED et al.; The generation of expressed sequenced tags (ESTs) depends on the arbitrary selection of individual cDNA clones from libraries . The efficiency of this process reflects the clonal structure of the library used and can be significantly increased using size selected, directional, normalized cDNA libraries . This strategy, however, is not readily applicable when mRNA is limiting, as is the case in the study of complex microorganisms such as parasites, fetal tissues or tumor biopsies . We show here that the construction and systematic sequencing of minilibraries of cDNAs produced by arbitrarily primed PCR provides an alternative means of efficiently generating ESTs in situations where only nanogram quantities of RNA are available . This methodology greatly compensates for unequal message abundance, avoids the need for complex library construction, is equally applicable to the analysis of abundant or rare biological material and is ideally suited to multicenter programmes. Front Biosci, 1997 Feb 15, 2, d78 - 87 Mast cells as modulators of host defense in the lung; Abraham SN et al.; Mast cells display a distinct spatial distribution in the lung where they are found preferentially in intraepithelial locations or in deeper tissue around blood vessels, bronchioles and mucus secreting glands . Yet the physiological role of these granule-laden cells is unknown . There are now intriguing signs that their distinctive distribution together with their intrinsic capacity to release large amounts of inflammatory mediators serve a critical role in immune surveillance . Mast cells have now been shown to be capable of recognizing and aggressively reacting to a wide range of bacteria . The mast cell responses involve ingesting and killing of adherent bacteria, in a manner not unlike that of traditional phagocytic cells . Concomitant with this endocytic activity, a large variety of potent inflammatory mediators are released by the mast cell . One such mast cell-derived mediator, TNF-alpha, was recently shown to be a critical signal for initiating neutrophil influx to sites of bacterial infection in the lung as well as the peritoneum of mice . This capacity of mast cells to recruit neutrophils, together with its recently reported participation in processing and presenting bacterial antigens to immune cells and in mediating proliferation of epithelial cells and mucosal mucus secretion, indicate that mast cells have an extraordinary ability to modulate the innate as well as adaptive immune responses to infectious microorganisms. Eur J Biochem, 1997 Feb 15, 244(1), 186 - 91 Enzymes from cold-adapted microorganisms . The class C beta-lactamase from the antarctic psychrophile Psychrobacter immobilis A5; Feller G et al.; A heat-labile beta-lactamase has been purified from culture supernatants of Psychrobacter immobilis A5 grown at 4 degrees C and the corresponding chromosomal ampC gene has been cloned and sequenced . All structural and kinetic properties clearly relate this enzyme to class C beta-lactamases . The kinetic parameters of P . immobilis beta-lactamase for the hydrolysis of some beta-lactam antibiotics are in the same range as the values recorded for the highly specialized cephalosporinases from pathogenic mesophilic bacteria . By contrast, the enzyme displays a low apparent optimum temperature of activity and a reduced thermal stability . Structural factors responsible for the latter property were analysed from the three-dimensional structure built by homology modelling . The deletion of proline residues in loops, the low number of arginine-mediated H-bonds and aromatic-aromatic interactions, the lower global hydrophobicity and the improved solvent interactions through additional surface acidic residues appear to be the main determinants of the enzyme flexibility. Pharmacoeconomics, 1997 Mar, 11(3), 216 - 24 Is Helicobacter pylori eradication a cost-effective treatment of duodenal ulcer disease? Carrere MO, Lamouliatte H, Ruszniewski P. Treatment strategies aimed at eradicating Helicobacter pylori have shown positive results in the management of duodenal ulcer disease . Several cost-effectiveness studies comparing these regimens with traditional therapy have recently been conducted, and results are discussed in this review . Cost comparisons of different treatment strategies cannot be performed without first identifying whether the cost of ulcer diagnosis is included in the study . Assuming that only 20% of patients with dyspepsia actually have ulcer disease, costs may vary, depending on the study population . Importantly, treatment costs should not be compared between a patient population with confirmed ulcer disease and one without confirmed disease . In patients with confirmed ulcer disease, studies consistently show that H . pylori eradication strategies are associated with greater efficacy and lower costs than traditional treatment, and are therefore a more cost-effective alternative to standard therapy . Although all models used in the cost-effectiveness analyses assume that patients discontinue treatment following successful eradication of the microorganism, in clinical practice some patients continue antisecretory treatment beyond this period . Thus, savings as a result of H . pylori eradication may be less substantial than indicated in cost-effectiveness studies. Actas Urol Esp, 1997 Feb, 21(2), 171 - 4 {Molluscum contagiosum in immunodepressed patient}; Caballero Alcantara J et al.; Molluscum contagiosum is a skin lesion caused by a poxviridae virus . Infection in children takes place through cutaneous contact while in adults results from sexual contact or under immunosuppression conditions . In immunosuppressed patients this infection is caused by opportunistic microorganisms and, basically, its appears when CD4 levels reach a certain decline, therefore its presence can be considered as a marker for poor prognosis or advanced stage of the disease. Home Care Provid, 1997 Feb, 2(1), 46 - 8 The epidemiology of disease transmission; Sharbaugh RJ; As inhabitants of the planet Earth, we live in a veritable sea of microorganisms . Virtually every aspect of our environment is heavily populated with different forms of microbial life . From the air we breathe to the food we eat, our daily existence is in the direct presence of literally billions of microorganisms. Exp Eye Res, 1997 Feb, 64(2), 203 - 9 Expression of aquaporins in the rat ocular tissue; Patil RV et al.; The aquaporins (AQPs) are a rapid growing family of water channel proteins found in animals, plants and microorganisms that raise plasma membrane water permeability required for efficient isosmotic fluid transport . Five homologs of aquaporins (AQP1, AQP2, AQP3, AQP4 and AQP5) have been identified from various mammalian tissues; the expression of these aquaporins in ocular tissues was studied . Semiquantitative expression levels of these aquaporins were determined in ciliary body, cornea, lens, retina, iris and choroid using RT-PCR . Expression levels of AQP1 are highest among the known aquaporins in each rat ocular tissue examined . In cornea, AQP1 is expressed approximately three-fold higher than AQP3 and 2.5 fold higher than AQP5 . However, the highest intraocular expressions of AQP3 and AQP5 are in the cornea . In the iris, expression levels of AQP1 are approximately 600-700 fold higher than AQP4 and AQP5 . In the ciliary body, the expression levels of AQP1 are approximately ten-fold higher than AQP4, the only other aquaporin expressed . In the lens, the major water channel is AQP1 with detectable levels of AQP4 and AQP5 that are approximately 1000-fold lower than AQP1 . In choroid, AQP1 is the only water channel expressed . In retin, AQP1 is expressed approximately six-fold higher than AQP4, the only other aquaporin expressed . However, the highest ocular expression of AQP4 is in retina . AQP2 is not detected in the eye . Finally, the possible physiological roles of aquaporins in maintaining and regulating the aqueous flow, and corneal and lens transparency are discussed. HNO, 1997 Feb, 45(2), 65 - 8 {3D computer-assisted ENT biopsies of the Iceman}; Thumfart WF et al.; The University of Innsbruck possesses a unique prehistoric, completely conserved 5300-year-old human cadaver . We report our experiences during which ENT specialists collected samples from various cavities inside the Iceman . Guidance of biopsy instruments was accomplished with computer-assisted navigation based on Interventional Video Tomography . This technology allows surgical guidance by interlinking currently available imaging modalities with live endoscopic video . The system operates without patient fixation and is practically free of external contact . Apart from sterility, special precautionary measures were necessary to avoid contamination with heavy metals or microorganisms . Visual inspection of the samples of mucosa from the nose, maxillary sinus and larynx revealed the typical patterns of a human cadaver without overt pathology. Appl Biochem Biotechnol, 1997 Feb-Mar, 62(2-3), 131 - 49 Mechanism and potential applications of bio-ligninolytic systems in a CELSS; Sarikaya A et al.; A large amount of inedible plant material, generated as a result of plant growth in a Controlled Ecological Life Support System (CELSS), should be pretreated and converted into forms that can be recycled on earth as well as in space . The main portion of the inedible biomass is lignocellulosic material . Enzymatic hydrolysis of this cellulose would provide sugars for many other uses by recycling carbon, hydrogen, oxygen, and nitrogen through formation of carbon dioxide, heat, and sugars, which are potential foodstuffs . To obtain monosaccharides from cellulose, the protective effect of lignin should be removed . White-rot fungi degrade lignin more extensively and rapidly than other microorganisms . Pleurotus ostreatus degrades lignin effectively, and produces edible and flavorful mushrooms that increase the quality and nutritional value of the diet . This mushroom is also capable of metabolizing hemicellulose, thereby providing a food use of this pentose containing polysaccharide . This study presents the current knowledge of physiology and biochemistry of primary and secondary metabolisms of basidiomycetes, and degradation mechanism of lignin . A better understanding of the ligninolytic activity of white-rot fungi will impact the CELSS Program by providing insights on how edible fungi might be used to recycle the inedible portions of the crops. Surg Laparosc Endosc, 1997 Feb, 7(1), 38 - 41 Effects of CO2 insufflation on bacterial growth in rats with Escherichia coli-induced experimental peritonitis; Sare M et al.; The effects of i.p . CO2 insufflation on bacterial proliferation in a setting of Escherichia coli-induced experimental peritonitis was studied in a rat model . Six male Wistar rats were given 0.25 ml of i.p . saline and formed the sham operation group . Twenty-four rats were divided into three groups, and all had i.p . E . coli injections . Microorganism counts were taken after 8 h in all groups . Group 1 was used as the control group . Group 2 (laparoscopy) was insufflated with CO2, and group 3 (laparotomy) had a midline laparotomy . Microorganism counts were repeated 8 h after the procedures (16 h after i.p . E . coli inoculation) . Postoperative microorganism counts were significantly higher in the CO2 insufflation group (p < 0.05) compared with the control and laparotomy groups and showed an increase, whereas they decreased in the other two groups. Prog Urol, 1997 Feb, 7(1), 132 - 6 {Urogenital infections linked to Chlamydia and mycoplasmas}; Fourmaux S et al.; Chlamydia trachomatis is responsible for urogenital infections, often minimally symptomatic, revealed by their complications . Mycoplasmas, mainly Ureaplasma urealyticum and Mycoplasma hominis, are normal commensal organisms of the genital tract, which sometimes makes it difficult to determine their pathogenicity . However, they are responsible for urogenital infections, and U . urealyticum is a pathogen in male urethris . The laboratory diagnosis is based on specific techniques adapted to these microorganisms . In the case of C . trachomatis, it has benefited from the recent progress in molecular biology techniques . The therapeutic approach is common to both types of organisms: tetracyclines and macrolides are the major antibiotics used in the treatment of these urogenital infections. J Periodontal Res, 1997 Feb, 32(2), 233 - 40 Vital microorganisms in early supragingival dental plaque and in stimulated human saliva; Weiger R et al.; The aim of this study was to compare the percentage of vital microorganisms (= microbial vitality) of saliva with that of supragingival plaque both collected at various times during the early phases of de novo plaque formation . Between intervals of optimal oral hygiene, 14 healthy participants refrained from all oral hygiene measures for periods of 1, 4, 8 and 72 h . Stimulated whole saliva was collected at the beginning (= baseline) and the end of each period . Vestibular plaque was removed from teeth 13-16, and 23-26 . Analysis of the pooled plaque (p) and saliva (s) samples comprised the total number of bacterial counts and colony-forming units to estimate the percentage of viable microorganisms (PEp; PEs) . The microbial vitality (VFp; VFs) was determined by using a fluorescence staining to differentiate vital from dead bacterial cells . The bulk of the PEs values reached 5-30% . At baseline VFs ranged between 70% and 90% . The VFs values recorded at baseline or in the presence of 1 h and 4 h-old plaque, were significantly (alpha = 0.05) higher than the corresponding VFp values ranging from 5% to 30% . It was concluded that there is a considerable discrepancy between the microbial vitality of a very early dental plaque and that of whole surrounding saliva sampled at the same time . Unfavourable local environmental conditions prevailing at cervical tooth surfaces are suggested to restrain the survival of the majority of the first bacteria adhering to a particular tooth area during the early phases of supragingival plaque formation. Occup Environ Med, 1997 Feb, 54(2), 125 - 34 Survey of the use of personal protective equipment and prevalence of work related symptoms among dental staff; Allsopp J et al.; OBJECTIVES: Dental instruments such as the right angle or straight handpiece, air turbine, and ultrasonic scaler have the ability to produce dental aerosols containing water, saliva, microorganisms, blood, tooth particles, lubricating oil, and restorative materials . The purpose of this study was to find out whether personal protective equipment (mask, glasses) was used by dental personnel, and to investigate possible work related disease in the dental profession . METHODS: Cross sectional data were collected with a self administered questionnaire sent to 69 randomly chosen general dental practices in the West Midlands Region . All members of the dental team completed questionnaires (dentists (n = 122); nurses (n = 115); hygienists (n = 86); and receptionists (n = 74) and answered questions on use of personal protective equipment and the prevalence of upper and lower respiratory tract, eye, and skin symptoms (reported and work related) . Reception staff were included as a low exposure, control group . Also, a longitudinal study of dental hygienists was carried out on 31 people who had taken part in a similar study five years earlier . RESULTS: Use of a face mask and glasses differed between clinical groups with hygienists and nurses being the most and least prevalent users respectively . Although several reported symptoms were significantly more prevalent among clinical staff, only one work related symptom (skin rashes or itchy or dry skin) was reported by the clinical staff more than by the non-clinical receptionists . Among female clinical staff, age < 35 years and atopy were the factors that predisposed to work related symptoms . Also, reported symptoms were related to duration of use of instruments that generated aerosols . CONCLUSIONS: This study shows a low level of work related symptoms in dentistry, but highlights a group vulnerable to prolonged exposures to dental aerosols . It also supports the need for enforcement of the use of personal protective equipment among dental nurses. Mol Med Today, 1997 Feb, 3(2), 76 - 83 Insulin-dependent diabetes mellitus: the hypothesis of molecular mimicry between islet cell antigens and microorganisms; Maclaren NK et al.; Insulin-dependent diabetes mellitus (IDDM) in humans and the non-obese diabetic mouse is a polygenic disease, resulting from an autoimmune destruction of the insulin-secreting pancreatic beta cells . At least in NOD mice, the process is mediated through a T helper 1-cell-mediated cytotoxicity pathway . Although there is much circumstantial evidence to suggest that IDDM is environmentally induced, recent studies support the possibility that the inductive event involves cross-reactive immune responses to antigenic epitopes acting as molecular mimics between microbial proteins and autoantigens expressed by pancreatic insulin-secreting beta cells . The following article reviews the evidence for this concept. Eur J Biochem, 1997 Feb 1, 243(3), 577 - 96 Anaerobic metabolism of aromatic compounds; Heider J et al.; Aromatic compounds comprise a wide variety of low-molecular-mass natural compounds (amino acids, quinones, flavonoids, etc.) and biopolymers (lignin, melanin) . They are almost exclusively degraded by microorganisms . Aerobic aromatic metabolism is characterised by the extensive use of molecular oxygen . Monoxygenases and dioxygenases are essential for the hydroxylation and cleavage of aromatic ring structures . Accordingly, the characteristic central intermediates of the aerobic pathways (e.g . catechol) are readily attacked oxidatively . Anaerobic aromatic catabolism requires, of necessity, a quite different strategy . The basic features of this metabolism have emerged from studies on bacteria that degrade soluble aromatic substrates to CO2 in the complete absence of molecular oxygen . Essential to anaerobic aromatic metabolism is the replacement of all the oxygen-dependent steps by an alternative set of novel reactions and the formation of different central intermediates (e.g . benzoyl-CoA) for breaking the aromaticity and cleaving the ring; notably, in anaerobic pathways, the aromatic ring is reduced rather than oxidised . The two-electron reduction of benzoyl-CoA to a cyclic diene requires the cleavage of two molecules of ATP to ADP and P1 and is catalysed by benzoyl-CoA reductase . After nitrogenase, this is the second enzyme known which overcomes the high activation energy required for reduction of a chemically stable bond by coupling electron transfer to the hydrolysis of ATP . The alicyclic product cyclohex-1,5-diene-1-carboxyl-CoA is oxidised to acetyl-CoA via a modified beta-oxidation pathway; the ring structure is opened hydrolytically . Some phenolic compounds are anaerobically transformed to resorcinol (1,3-dihydroxybenzene) or phloroglucinol (1,3,5-trihydroxybenzene) . These intermediates are also first reduced and then as alicyclic products oxidised to acetyl-CoA . This review gives an outline of the anaerobic pathways which allow bacteria to utilize aromatics even in the absence of oxygen . We focus on previously unknown reactions and on the enzymes characteristic for such novel metabolism. Vet Microbiol, 1997 Feb, 54(2), 155 - 66 Detection of Chlamydia psittaci DNA in avian clinical samples by polymerase chain reaction; Hewinson RG et al.; A polymerase chain reaction (PCR) assay was developed to detect . Chlamydia psittaci DNA in faeces and tissue samples from avian species . Primers were designed to amplify a 264 bp product derived from part of the 5' non-translated region and part of the coding region of the ompA gene which encodes the major outer membrane protein . Amplified sequences were confirmed by Southern hybridization using an internal probe . The sensitivity of the combined assay was found to be between 60 to 600 fg of chlamydial DNA (approximately 6 to 60 genome copies) . The specificity of the assay was confirmed since PCR product was not obtained from samples containing several serotypes of C . trachomatis, strains of C . pneumoniae, the type strain of C . pecorum, nor from samples containing microorganisms commonly found in the avian gut flora . In this study, 404 avian faeces and 141 avian tissue samples received by the Central Veterinary Laboratory over a 6 month period were analysed by PCR, antigen detection ELISA and where possible, cell culture isolation . PCR performed favourably compared with ELISA and cell culture, or with ELISA alone . The PCR assay was especially suited to the detection of C . psittaci DNA in avian faeces samples . The test was also useful when applied to tissue samples from small contact birds associated with a case of human psittacosis where ELISA results were negative and chlamydial isolation was a less favourable method due to the need for rapid diagnosis. Epidemiol Infect, 1997 Feb, 118(1), 71 - 5 A simple device for the exposure of animals to infectious microorganisms by the airborne route; Phillpotts RJ et al.; In order to evaluate prophylaxis and therapy for individuals infected with pathogens by the airborne route, we have designed and built a simple apparatus in which small laboratory animals may be exposed to aerosols of infectious microorganisms . Animals are kept in a chamber closed by a HEPA filter and exposed to the pathogen aerosolized using a Collison nebulizer . Air in the exposure chamber may be sampled to show that the infectious agent is present but the dose of agent must be expressed as 50% effective doses determined by titration . An effective dose may be defined by whatever criteria are chosen to judge disease . Using this apparatus we have shown that St Louis encephalitis (SLE) virus is infectious for mice by the airborne route . These data support the idea that there may be significant hazard to personnel exposed to aerosols of infectious SLE after a laboratory accident. Chest, 1997 Feb, 111(2), 411 - 8 Usefulness of quantitative cultures of BAL fluid for diagnosing nosocomial pneumonia in ventilated patients; Jourdain B et al.; STUDY OBJECTIVE: To evaluate the role of quantitative cultures of BAL for diagnosing nosocomial pneumonia in mechanically ventilated patients . DESIGN: Cohort study . SETTING: Medical ICU, Hopital Bichat, Paris, France, an academic tertiary care center . PATIENTS: A total of 141 episodes of suspected lung infection in 84 consecutive patients mechanically ventilated for 48 h or more . MEASUREMENTS AND RESULTS: Microbiologic findings obtained using BAL were compared with those obtained with protected specimen brush (PSB) samples and their operating characteristics were determined . The level of qualitative agreement between BAL and PSB specimen cultures was high, with 83% of the organisms isolated in PSB specimens being recovered simultaneously from BAL fluid . In addition, the results of quantitative BAL and PSB cultures were significantly correlated (rho = 0.46, p < 0.0001) . Fifty-seven cases of pneumonia were diagnosed based on the following criteria: PSB sample yielding > or = 10(3) cfu/mL of at least one microorganism and/or > or = 5% of cells containing intracellular bacteria on direct examination of BAL . The operating characteristics of BAL fluid cultures were determined using different ways to report the results and over a range of values . The discriminative value of 10(4) cfu/mL was found to be an optimal threshold, with a sensitivity of 82% (95% confidence interval {CI}, 76 to 88) and a specificity of 84.5% (95% CI, 79 to 90) . CONCLUSIONS: These results indicate that BAL fluid cultures can offer a sensitive and specific means to diagnose pneumonia in ventilated patients and may provide relevant information about the causative pathogens. Pediatr Infect Dis J, 1997 Feb, 16(2), 163 - 79 The expanding spectrum of Bartonella infections: II . Cat-scratch disease; Bass JW et al.; Recent advancements and developments in molecular biotechnology have allowed more precise reclassification of many microorganisms . With the use of these new taxonomy tools, several organisms previously thought to belong to other genera have been recently described as bartonellae . Of the 11 organisms now described as Bartonella spp., only four have been shown to be pathogenic for humans . Table 1 lists the four Bartonella human pathogens along with the their known epidemiology and the scope and range of disease associated with each . All are now considered to be bacteria and can be grown on blood-enriched agar although primary isolation in some may best be achieved in cell tissue culture . B . bacilliformis infection is limited to certain geographic regions in South America where the only human reservoir and the sandfly vector(s) that spreads the disease reside together . Specific antibiotic treatment is dramatically effective in treating the highly fatal, acute intraerythrocytic hemolytic form of the disease, but their effectiveness in treating the vascular proliferative forms (verruga peruana) or the chronic asymptomatic, bacteremic, carrier state of the disease has not been effective . This disease should remain confined to its present endemic geographic areas in South American unless asymptomatic bacteremic persons from these areas migrate to areas where sandflies and humans exist that are capable of establishing this infection in new endemic areas . B . quintana and B . henselae cause a wide range of clinical diseases in humans, the type and extent of which varies significantly with the immune status of the host . In immunocompetent hosts the pathologic response is granulomatous, suppurative, extracellular and intracellular, generally self-limited and usually unresponsive to antibiotic treatment, even to those drugs to which the organism is shown to be sensitive in vitro . In contrast, in immunocompromised hosts the pathologic response is vasculoproliferative, organisms may be seen intracellularly but they are often seen in abundance in extracellular clumps and infection is usually progressive and fatal unless treated . In these patients clinical response to treatment with drugs that are effective in vitro against these organisms has usually been dramatic . Of these agents those that penetrate cells and are found in high concentrations intracellularly, such as erythromycin, clarithromycin, azithromycin, rifampin, doxycycline and gentamicin, appear to be most effective . These agents not only appear to provide the most dramatic treatment response in patients with BA, BP and PRFB and other manifestations of B . henselae (and B . quintana as well) in immunocompromised persons, they appear to be the most promising agents for treatment of persons with both typical and atypical CSD . Further studies will be necessary to more clearly elucidated the mechanisms responsible for the diverse clinical presentations of infection with these organisms in human hosts relative to their immune status . In addition clarification of the epidemiology of B . elizabethae infections in humans may be helpful in understanding the nature of infection with Bartonella organisms. FASEB J, 1997 Feb, 11(2), 133 - 40 Plant-type ferredoxin-NADP+ reductases: a basal structural framework and a multiplicity of functions; Arakaki AK et al.; Ferredoxin-NADP+ (oxido)reductase (EC 1.18.1.2, FNR) is an FAD-containing enzyme that catalyzes the reversible electron transfer between NADP(H) and electron carrier proteins such as ferredoxin and flavodoxin . Isoforms of this flavoprotein are present in chloroplasts, mitochondria, and bacteria in which they participate in a wide variety of redox metabolic pathways . Although ferredoxin-NADP+ reductases have been thoroughly investigated and their properties reviewed on several occasions, considerable advances in the understanding of these flavoenzymes have occurred in the last few years, including the characterization of cDNA and genomic clones encoding FNR proteins from plants, algae, vertebrates, and bacteria, determination of the atomic structure of a plant FNR at high resolution, and the expression of functional reductases in microorganisms like Escherichia coli and Saccharomyces cerevisiae . The aim of this article is to summarize information gained through these recent developments, including the phylogenetic relationships among ferredoxin reductases and the key structural features of the plant FNR family . Other aspects such as the catalytic mechanism of FNR and the molecular events underlying biogenesis, intracellular sorting, folding, and holoenzyme assembly of this important flavoenzyme are also discussed in some detail . Ferredoxin-NADP+ reductases display several outstanding properties that make them excellent model proteins to address broad biological questions. Curr Opin Immunol, 1997 Feb, 9(1), 57 - 63 An innate view of gamma delta T cells; Boismenu R et al.; Findings made during the past few years demonstrate that gamma delta T cells apparently share with macrophages a propensity to recognize nonpeptidic molecules of the kind most commonly associated with microorganisms and stressed cells . In general, recognition of these antigens by gamma delta T cells involves the antigen receptor but does not require antigen presenting cells to express MHC gene products or to have a functional antigen processing machinery . Other recent advances continue to support the notion that gamma delta T cells can perform specialized functions related to the repair of tissue damage. Appl Environ Microbiol, 1997 Feb, 63(2), 806 - 11 Introduction of anaerobic dechlorinating bacteria into soil slurry microcosms and nested-PCR monitoring; el Fantroussi S et al.; Desulfomonile tiedjei and Desulfitobacterium dehalogenans were chosen as model bacteria to demonstrate the introduction of an anaerobic microbia reductive dechlorination activity into nonsterile soil slurry microcosms by inoculation . De novo 3-chlorobenzoate dechlorination activity was established with the bacterium</