Antimicrob Agents Chemother, 1995 Mar, 39(3), 739 - 45 Antigenic properties and immunoelectron microscopic localization of Mycobacterium fortuitum beta-lactamase; Wagner B et al.; Mycobacterium fortuitum is a fast-growing Mycobacterium species which produces a beta-lactamase involved in the intrinsic resistance of the microorganism to beta-lactam antibiotics . An anti-beta-lactamase serum against the purified enzyme was raised in rabbits . Antibody binding was specific for native beta-lactamase, and enzyme activity was partially inhibited by the serum; furthermore, cross-reactions with denatured class A beta-lactamases were observed . This serum was used as a probe in immunogold labeling for the localization of the cell-bound beta-lactamase in both the low-level producer ATCC 19542 (parental strain) and the overproducer mutant D316 . By the combination of preembedding immunogold labeling and replica technique, it was shown that the beta-lactamase was uniformly distributed on the whole external cell surface, where it appeared to be associated with a Tween 80-removable capsule-like material . Compared with the parental strain, a much higher level of expression of surface enzyme was observed in strain D316 . Surface labeling was more intense in the stationary phase of growth than in exponentially growing cells . The data obtained are interpreted in the context of the intrinsic resistance of M . fortuitum to beta-lactam antibiotics. Vet Pathol, 1995 Mar, 32(2), 134 - 9 Higher incidence of Gastrospirillum sp . in swine with gastric ulcer of the pars oesophagea; Barbosa AJ et al.; Gastric ulcer in swine is characterized by an area of acid-peptic digestion, occurs usually in the pars oesophagea of the stomach, and has unknown etiopathogenesis . The present work was carried out to investigate the prevalence of the newly described spiral-shaped microorganism Gastrospirillum sp . ("Gastrospirillum suis") in stomachs of abattoir pigs with and without gastric ulcer . Stomachs were removed from 32 consecutive pigs presenting apparently normal mucosa and from 32 additional consecutive pigs presenting frank, chronic gastric ulcer of the pars oesophagea . Fragments of antral, oxyntic, cardiac and pars oesophagea regions were taken from each stomach and processed for histology and for identification of Gastrospirillum sp . in tissue sections . The microorganisms were identified mainly in the mucous layer and in gastric foveolas of the antral and oxyntic mucosa . Forty pigs (62.5%) were positive for Gastrospirillum sp.; among them, 27 (67.5%) had gastric ulcer, and 13 (32.5%) had no ulcer . Twenty-four pigs (37.5%) were negative for Gastrospirillum sp.; among them, five (20.8%) presented with gastric ulcer, and 19 (79.2%) had no ulcer . There was a significant difference between pigs with and without gastric ulcer in regard to the presence of Gastrospirillum sp . (P < 0.01) . The spiral-shaped microorganism Gastrospirillum sp . that inhabits the stomach of pigs should be considered a possible factor connected with the etiopathogenesis of swine gastric ulcer. Clin Chest Med, 1995 Mar, 16(1), 29 - 44 Epidemiology of nosocomial pneumonia in intensive care unit patients; George DL; Pneumonia is the most commonly reported nosocomial infection in ICU patients, occurring predominantly in patients whose lungs are ventilated, at a rate of 1% to 3% per day of mechanical ventilation . Substantially increased costs and mortality have been attributed to nosocomial pneumonia . Our understanding of the epidemiology of nosocomial pneumonia in ICU populations has been limited by the reliance of most published studies on clinical diagnostic criteria, which are nonspecific . In addition to mechanical ventilation and tracheal intubation, other suspected risk factors of importance include chronic lung disease, age, severity of illness, upper abdominal or thoracic surgery, head trauma or depressed level of consciousness, and gastric acid inhibition . Aspiration appears to be the primary mode of inoculation of microorganisms into the distal lung; however, the relative importance of different sites as reservoirs for aspiration is controversial . It is hoped that studies based on improved diagnostic techniques, such as quantitative cultures of protected brush or bronchoalveolar lavage specimens, will provide the basis for an improved understanding of the epidemiology and prevention of this important infection in critically ill patients. Plant Mol Biol, 1995 Mar, 27(5), 995 - 1001 Characterization of two proteinase inhibitor (ATI) cDNAs from alfalfa leaves (Medicago sativa var . Vernema): the expression of ATI genes in response to wounding and soil microorganisms; McGurl B et al.; cDNAs encoding two Bowman-Birk proteinase inhibitors were isolated from the leaves of alfalfa (Medicago sativa) . The cDNAs are derived from a small gene family (3 to 10 genes) encoding alfalfa trypsin inhibitors (ATIs) . Each cDNA clone encoded a mature ATI that was part of a larger, putative preprotein . ATI mRNAs are continuously expressed in flower parts, but are mechanically wound-inducible in the stems and leaves . ATI mRNA is shown to be continuously present in roots of soil-grown plants, but its presence is primarily in response to microorganisms present in the soil . Additionally, while mechanical wounding of the alfalfa roots induced ATI mRNA synthesis both in the roots and in the leaves, microbial infection of the roots triggered ATI mRNA synthesis in the roots but not in the leaves . These results suggest that both local and systemic signalling pathways for proteinase inhibitor synthesis are present in alfalfa plants. Biosci Biotechnol Biochem, 1995 Mar, 59(3), 487 - 91 Purification and properties of fructosyl lysine oxidase from Fusarium oxysporum S-1F4; Sakai Y et al.; Fructosyl lysine oxidase (FLOD) was examined for its use in the enzymatic measurement of the level of glycated albumin in blood serum . To isolate microorganisms having such an enzyme activity, we used N epsilon-fructosyl N alpha-Z-lysine (epsilon-FL) as a sole nitrogen source in the enrichment culture medium . The isolated fungus, strain S-1F4, showed a high FLOD activity in the cell-free extract and was identified as Fusarium oxysporum . FLOD was purified to an apparent homogeneity on SDS-PAGE . The molecular mass of the subunit was 50 kDa on SDS-PAGE and seemed to exist in a monomeric form . The enzyme had an absorption spectrum characteristic of a flavoprotein and the flavin was found to be covalently bound to the enzyme . The enzyme acted against N epsilon-fructosyl N alpha-Z-lysine and N alpha-fructosyl N epsilon-Z-lysine and showed specificity for fructosyl lysine residues. In Vitro Cell Dev Biol Anim, 1995 Mar, 31(3), 196 - 206 A polarized human endometrial cell line that binds and transports polymeric IgA; Ball JM et al.; We have demonstrated that a human endometrial cell line, HEC-1, maintains a transepithelial electrical resistance, directionally transports fluids across the cell monolayer, and releases enveloped viruses at distinct plasma membrane domains: influenza virus is released at the apical surfaces and vesicular stomatitis virus (VSV) at the basolateral surfaces . In addition, we have examined the expression of domain-specific endogenous proteins, including the polyimmunoglobulin receptor . Multiple endogenous polypeptides were found to be secreted into the culture medium at basolateral surfaces, whereas no secretion of specific polypeptides was observed from apical cell surfaces . Distinct patterns of endogenous proteins were also observed on apical and basolateral cell surfaces, with a much more complex polypeptide pattern on the basolateral membranes . Using surface biotinylation and immunofluorescence, the polyimmunoglobulin receptor was found to be expressed on the basolateral surface of HEC-1 monolayers . The specific binding of poly-immunoglobulin A (pIgA) was found to occur on the basolateral surface, and was followed by transcytosis to the apical surface and release into the apical medium . The observed characteristics indicate that the endometrium-derived HEC-1 epithelial cell line can be employed as a model for studies of protein transport in polarized epithelial cells of human endometrial tissues, as well as for studies of the interaction of microorganisms with epithelial cells in the genital tract. Plant J, 1995 Mar, 7(3), 367 - 79 Molecular evolution of plant beta-glucan endohydrolases; Hoj PB et al.; The evolutionary relationships of two classes of plant beta-glucan endohydrolases have been examined by comparison of their substrate specificities, their three-dimensional conformations and the structural features of their corresponding genes . These comparative studies provide compelling evidence that the (1-->3)-beta-glucanases and (1-->3,1-->4)-beta-glucanases from higher plants share a common ancestry and, in all likelihood, that the (1-->3,1-->4)-beta-glucanases diverged from the (1-->3)-beta-glucanases during the appearance of the graminaceous monocotyledons . The evolution of (1-->3,1-->4)-beta-glucanases from (1-->3)-beta-glucanases does not appear to have invoked 'modular' mechanisms of change, such as those caused by exon shuffling or recombination . Instead, the shift in specificity has been acquired through a limited number of point mutations that have resulted in amino acid substitutions along the substrate-binding cleft . This is consistent with current theories that the evolution of new enzymic activity is often achieved through duplication of the gene encoding an existing enzyme which is capable of performing the required chemistry, in this case the hydrolysis of a glycosidic linkage, followed by the mutational alteration and fine-tuning of substrate specificity . The evolution of a new specificity has enabled a dramatic shift in the functional capabilities of the enzymes . (1-->3)-beta-Glucanases that play a major role, inter alia, in the protection of the plant against pathogenic microorganisms through their ability to hydrolyse the (1-->3)-beta-glucans of fungal cell walls, appear to have been recruited to generate (1-->3,1-->4)-beta-glucanases, which quite specifically hydrolyse plant cell wall (1-->3,1-->4)-beta-glucans in the graminaceous monocotyledons during normal wall metabolism . Thus, one class of beta-glucan endohydrolase can degrade beta-glucans in fungal walls, while the other hydrolyses structurally distinct beta-glucans of plant cell walls . Detailed information on the three-dimensional structures of the enzymes and the identification of catalytic amino acids now present opportunities to explore the precise molecular and atomic details of substrate-binding, catalytic mechanisms and the sequence of molecular events that resulted in the evolution of the substrate specificities of the two classes of enzyme. Clin Infect Dis, 1995 Mar, 20(3), 501 - 6 Infective endocarditis in patients with negative blood cultures: analysis of 88 cases from a one-year nationwide survey in France; Hoen B et al.; Blood cultures were negative in 88 (14%) of 620 cases of infective endocarditis (IE) documented in France during a 1-year nationwide survey . In 15 of these 88 cases, the causative microorganism was identified: seven cases of Q fever endocarditis and two cases of chlamydial endocarditis were diagnosed by serological and/or immunohistologic techniques, and a pathogen was cultured from five surgically removed valves and one arterial septic embolus . Forty-two (48%) of the 88 cases involved patients who had received antibiotics before the first blood sample was taken for culture . Mortality was lower in this group than among patients who had not previously received antibiotics (7% vs . 22%, P = .05) . Comparison of blood culture-negative cases of IE with blood culture-positive cases revealed that the former tended to occur more often on prosthetic valves (32% vs . 22%, P = .16), were more often left-sided (97% vs . 83%, P = .0009), less often included extracardiac symptoms at presentation (52% vs . 63%, P = .06), and were more often surgically treated (53% vs . 34%, P = .001) . Mortality was similar regardless of the results of blood culture (15% vs . 21%, P = .18) . This study showed that more than 10% of all cases of IE in France are still associated with negative blood cultures and confirmed that a search for pathogens such as Coxiella burnetii and Chlamydia species is worthwhile in this situation. Mutat Res, 1995 Mar, 346(3), 145 - 9 Genotoxic activity in vivo of the naturally occurring glucoside, cycasin, in the Drosophila wing spot test; Kawai K et al.; Cycasin, methylazoxymethanol-beta-glucoside, is a naturally occurring carcinogenic compound . The genotoxicity of cycasin was assayed in the Drosophila wing spot test . Cycasin induced small single and large single spots on feeding at 10 mumol/g medium . The presence of these spots indicates that cycasin is genotoxic in Drosophila melanogaster . Microorganisms which showed beta-glucosidase activity for cleaving cycasin to toxic aglycon were isolated from gut flora of the Drosophila larvae . Consequently, the Drosophila wing spot test would be useful for mutagenicity screening of other naturally occurring glucosides. J Steroid Biochem Mol Biol, 1995 Mar, 52(3), 271 - 5 The role of cytochrome P450(11 alpha) in detoxification of steroids in the filamentous fungus Rhizopus nigricans; Breskvar K et al.; The evidence was presented that steroid hydroxylating enzyme complex induced by substrate in the filamentous fungus Rhizopus nigricans (R . nigricans) alleviated toxic effect(s) of the steroid on fungal growth . The growth inhibition of fungal mycelium observed in steroid-containing culture(s) became much more obvious when fungal mycelia were grown in the simultaneous presence of inducing steroid and the P450(11 alpha) inhibitor metyrapone . On the other hand, in experiments where we followed the fate of radioactively labelled progesterone added to the mycelial suspension, we noticed that steroid, after being initially accumulated in the microorganism, was, after some time, released from it; the latter phenomenon was not observed if induction of 11 alpha-hydroxylase was prevented by cycloheximide . Results of experiments presented in this communication can be regarded as the first strong indication that the biological role of P450(11 alpha) induction in R . nigricans is in removal of steroids which are toxic for the mycelium. Minerva Anestesiol, 1995 Mar, 61(3), 77 - 81 {Role of slime in the pathogenesis of pulmonary infections}; Chini G et al.; Microorganisms have proved to produce an amorphous substance that adheres to surfaces of several medical devices like intravenous catheters and endotracheal tubes . We investigated the presence of slime in endotracheal tubes in our Intensive Care Unit (ICU) in 12 patients . We found in this study no correlation between the strain of bacteria on the surface of endotracheal devices and those responsible for pneumonia. Ann Ital Chir, 1995 Mar-Apr, 66(2), 217 - 22 Clinical significance and management of pancreatic abscess and infected necrosis complicating acute pancreatitis; Bittner R; Secondary pancreatic infections are most serious and life threatening complications of acute necrotizing pancreatitis . The risk of secondary infection is to a large extend related to duration and extension of pancreatic or peripancreatic necrosis . The combination of abdominal CT-scan with guided percutaneous needle aspiration has been demonstrated to be highly reliable on differentiating between sterile and infected pancreatic necrosis . Previous results suggest a major role of enteric pathogens in this disease . Due to the type of microorganisms and the defence capacity of the patient, the pancreatic infection might result in either elimination of the microorganism, unlimited propagation within devitalized tissue (infected necrosis) or they may remain localized (abscess formation) . Though the most fulminant course of acute pancreatitis is found in patients with early infected necrosis . In these cases an operation is usually necessary within 14 days after onset of symptoms . Persistence or new development of typical symptoms two to five weeks after initial improvement should raise the suspicion of abscess . The finding of infection is an absolute indication for surgical intervention . The intention of surgical treatment in combination with antibiotic therapy is to remove devitalized pancreatic and peripancreatic tissue, evacuate all purulent material and provide continuous drainage either by lavage or "open" abdominal treatment . In this article basic procedures of diagnosis and therapy are discussed. Xenobiotica, 1995 Mar, 25(3), 229 - 37 Age-dependent intestinal hydrolysis of valproate glucuronide in rat; Slattum PW et al.; 1 . Age-dependent differences in the intestinal hydrolysis of the glucuronide conjugate of valproic acid were evaluated in the Fisher-344 rat at 14 and 40 days, and 24 months of age . 2 . Hydrolysis occurred more quickly when incubations were conducted under anaerobic as compared with aerobic conditions . 3 . The rate of hydrolysis of valproate glucuronide was most rapid in the contents of the large intestine (caecum and colon); no difference in rate was noted between age groups during incubations with large intestinal contents . 4 . Hydrolysis in the tissues of the large and small intestines, and the contents of the small intestine, was more rapid in the 14-day-old rat than in the older age groups . Differences in the rates and sites of hydrolysis in the 14-day-old animal may be due to regional differences in the number and types of microorganisms or mammalian beta-glucuronidase present in the gastrointestinal tract . 5 . Differences in intestinal hydrolysis of valproate glucuronide may account in part for age-related changes in enterohepatic recirculation of valproate in young animals; other mechanisms apparently are responsible for altered valproate disposition in senescent animals. Eur J Clin Microbiol Infect Dis, 1995 Mar, 14(3), 234 - 7 Presence of Helicobacter pylori in the oral cavity, oesophagus, stomach and faeces of patients with gastritis; Namavar F et al.; The presence of Helicobacter pylori in the oral cavity (6 sites), oesophagus, stomach and bowel of 20 dyspeptic patients was investigated . Samples were cultured on three selective media and analyzed by 16S rDNA polymerase chain reaction (PCR) and southern hybridization . Helicobacter pylori DNA was detected by PCR from oral-cavity samples of three (20%) and from faeces samples of only one (7%) of the patients whose stomach biopsies were positive for Helicobacter pylori . When culture was used, the microorganism's rate of recovery from the oral cavity and faeces was 13% and 7%, respectively . One patient had a Helicobacter pylori-like organism in samples collected from the tongue and palate . Both strains were urease, catalase and oxidase positive and grew microaerophilically but were negative on PCR analysis . This demonstrates the possibility of false identification of Helicobacter pylori by use of routine enzyme reactions . Interestingly, specimens collected from the cheeks of three patients were positive for Helicobacter pylori by PCR analysis . This is the first instance of detection of this microorganism in the cheek. Acta Gastroenterol Belg, 1995 Mar-Apr, 58(2), 193 - 200 Gastric carcinoma: the Helicobacter pylori trail; Deltenre M et al.; Gastric carcinoma is the world's overall second most common cancer . Besides obvious environmental factors, recent epidemiological studies and a better knowledge of Helicobacter Pylori biological properties revealed that the microorganism is involved in the first steps of gastric carcinogenesis as proposed by the Correa model (from normal gastric tissue through superficial gastritis, multifocal atrophic gastritis, intestinal metaplasia and dysplasia to carcinoma) . Significant correlation between the prevalence of H . pylori infection and incidence of gastric carcinoma (mainly the intestinal type) in various geographical areas has been reported . The high prevalence of HP in pre-neoplastic states and in cases of early gastric cancer indicates the infection would precede the development of gastric cancer . HP-related chronic inflammation of gastric mucosa with increased mucosal cell proliferation, deficit in local ascorbic acid concentration, topical ammonia toxicity are putative mechanisms that overexpose a weakened gastric mucosa to environmental carcinogens. Microb Pathog, 1995 Mar, 18(3), 197 - 209 Molecular investigation of the role of ApxI and ApxII in the virulence of Actinobacillus pleuropneumoniae serotype 5; Reimer D et al.; The extracellular hemolytic toxins (ApxI and ApxII) of Actinobacillus pleuropneumoniae are thought to be important factors in this microorganism's virulence and the pathogenesis of swine pleuropneumonia . Using the polymerase chain reaction, the apxI locus of a non-hemolytic, avirulent mutant of A . pleuropneumoniae serotype 5 (mIT4-H) generated by chemical mutagenesis (Inzana T . J., Todd J., Veit H . P . Microb Pathog 1991; 10: 281-96) was found to contain deletions that affected major parts of the entire apxICABD operon, thus inactivating each gene in the operon . The apxII locus was not affected . Monoclonal antibodies to ApxI and ApxII were used to confirm that ApxI was not synthesized, and that ApxII was synthesized but not secreted from the cell . The apxICABD genes and apxIBD genes were cloned into a broad host range vector to obtain plasmids pJFF800 and pJFF801, respectively . Each recombinant plasmid was electroporated into strain mIT4-H to obtain strain mIT4-H/pJFF800 and strain mIT4-H/pJFF801, respectively . Strain mIT4-H/pJFF800 exported ApxI and ApxII, and produced hemolytic activity comparable to or exceeding that of wild type strain J45 . Strain mIT4-H/pJFF801 exported only ApxII and produced weak hemolytic activity . Strain mIT4-H/pJFF800 was virulent in mice, and had an LD50 of about 2 x 10(6) colony forming units . In contrast, mIT4-H/pJFF801 and mIT4-H were essentially avirulent in mice, and LD50s for these strains could not be calculated . Strain mIT4-H/pJFF800 was virulent in pigs and caused lethal pleuropneumonia, whereas parent strain mIT4-H was avirulent . Strain mIT4-H/pJFF801 was also able to induce pleuropneumonia in pigs, although a higher dose was required to induce lesions similar to those caused by mIT4-H/pJFF800 . Thus, A . pleuropneumoniae strains that produce ApxI and ApxII require ApxI for full virulence and toxic activity in pigs . However, other factors including ApxII contribute to the virulence of A . pleuropneumoniae in pigs. Rev Sci Tech, 1995 Mar, 14(1), 21 - 39 History of disinfection from early times until the end of the 18th century; Blancou J; The author describes and analyses the methods of disinfection in use until the end of the 18th century, i.e . before the scientific demonstration of the role of pathogenic microorganisms . These methods are classified into three categories: chemical (by derivatives of sulphur, mercury, copper, and also by alkalis and acids), physical (heating, fumigation, filtration, etc.) and biological (burial) . The author concludes that, despite their empiricism, these methods were of great value to those responsible for controlling diseases of animals, as in some cases they were able to eradicate diseases while still ignorant of the causal mechanisms. Rev Sci Tech, 1995 Mar, 14(1), 177 - 89 Aircraft and ship disinfection; Cancellotti FM; Shipment of animals, animal products and foodstuffs (for human or animal consumption) by sea and air is economically important . However, the possibilities of pathogen transmission represent a genuine danger, even if veterinary controls are performed continuously . Bacteria, viruses, fungi and parasites excreted by animals may contaminate surfaces and are protected by organic matter . Cleaning is an important step in the sanitizing process, and if this is performed well, more than 90% of microorganisms can be removed . Chemical disinfectants must be compatible with cleaning procedures, instruments and materials used previously, and should be without harmful effects on humans or animals . The author outlines the basic procedures and fundamental principles involved. Microbiologia, 1995 Mar, 11(1), 23 - 32 {Food preservation through combined processes}; Sala Trepat FJ; Food preservation by combined processes is based on the combination of two or more existing preservation methods with the objective of developing milder preservation procedures . Currently two combined processes (CP) deserve a special attention, the preservation of food by high pressures (HP) and the preservation of food with the combined use of heat and ultrasounds under pressure (Mano-Thermo-Sonication) . In the preservation by HP, the food, at room temperature or at very mild temperature, is held during relatively long periods under very high pressures (100-1000 MPa) to inactivate its enzymes and/or microorganisms . This procedure has proved to be effective to inactivate vegetative cells but much less effective to inactivate most enzymes and bacterial spores . Several kinds of food preserved by this method have already been launched into the market . In Mano-Thermo-Sonication (MTS Process) microorganisms and enzymes are inactivated by a combined heat/ultrasounds treatment under pressure . By this method, the lethality of heat treatments at the same temperature is highly increased . Therefore, the intensity of heat treatments can be drastically reduced . Heat resistance of spores is reduced by a factor of 1/10 and that of enzymes and vegetative cells is reduced by a factor of 1/50 approximately . The applicability of this procedure is currently being investigated. Microbiologia, 1995 Mar, 11(1), 115 - 24 {Biological control in the preservation of pome fruits}; Vinas I; Fresh fruits are susceptible of be attacked by several pathogenic fungi after harvest due to both their high water and nutrients content and their loss of most of the intrinsic resistance that protected them over their development while attached to the plant . Most rot pathogens can be controlled by various methods such as refrigeration, controlled atmospheres and fungicides . Biological control strategies are emerging as promising alternatives to the use of synthetic fungicides . Several factors must be considered for the selection of biocontrol agents to be used against postharvest fruits diseases . Survivability of the antagonist is a major factor to determine its usefulness . Antagonists must survive and be effective after their exposure to both postharvest treatments and storage conditions . Several antagonistic microorganisms have been found that can effectively inhibit postharvest diseases . Just as there is a diversity among microorganisms, there is also a diversity of mechanisms by which they operate . Although in most cases these mechanisms have not been satisfactorily elucidated, they are likely to involve antibiosis, nutrient competition, stimulation of host defense, predation and parasitism . In many cases, probably more than one mechanism operate . The marketing of some of these antagonists may be feasible and they could be an alternative to synthetic pesticides. J Biol Chem, 1995 Feb 24, 270(8), 3560 - 4 Interaction of the hemolytic lectin CEL-III from the marine invertebrate Cucumaria echinata with the erythrocyte membrane; Hatakeyama T et al.; CEL-III is one of four Ca(2+)-dependent galactose/N-acetylgalactosamine (GalNAc)-binding lectins from the marine invertebrate Cucumaria echinata which exhibits hemolytic activity, especially toward rabbit and human erythrocytes . The hemolytic activity of CEL-III was also Ca(2+)-dependent and was found to be inhibited by galactose or GalNAc-containing carbohydrates, suggesting that the hemolysis was caused by CEL-III binding to specific carbohydrates on the erythrocyte membrane by Ca(2+)-dependent lectin activity, followed by partial destruction of the membrane . The activity of CEL-III was highest at 10 degrees C and decreased markedly with increasing temperature, unlike usual enzymatic reactions . The hemolytic activity of CEL-III increased with increasing pH from neutral to 10, but almost no hemolysis was observed below pH 6.5 . Immunoblotting analysis of proteins from the erythrocyte membrane after treatment with CEL-III indicated that CEL-III aggregates were irreversibly bound to the membrane . When erythrocytes were incubated with CEL-III in the presence of dextran with molecular masses greater than 4 kDa, lysis was impeded considerably, while a concomitant release of ATP was detected from these osmotically protected cells . It was found that CEL-III released carboxyfluorescein from artificial globoside-containing lipid vesicles, and it is suggested that CEL-III is a novel pore-forming protein with the characteristics of a Ca(2+)-dependent lectin, which may act as a toxic protein to foreign microorganisms. FEMS Microbiol Lett, 1995 Feb 15, 126(2), 203 - 7 Evidence that the novel microorganism 'Z' may belong to a new genus in the family Chlamydiaceae; Kahane S et al.; The purpose of this study was to investigate possible phylogenetic relationships of a new microorganism called 'Z' . The organism was previously shown to be similar to chlamydia in its growth cycle and some of its metabolic requirements, but different in others and in its major outer membrane protein . In this study we report the sequencing of 'Z"s 16S ribosomal DNA and comparison of the sequence with that of other microorganisms, including chlamydia and rickettsiae . While chlamydial species have 95.5% sequence identity among themselves, 'Z' had 83% identity with them, and 73% identity with certain rickettsia-like organisms . Based on the sequence analyses and taking into account physiologic considerations, we believe that 'Z' may belong to a novel genus in the family Chlamydiaceae. Proc Natl Acad Sci U S A, 1995 Feb 14, 92(4), 939 - 43 cDNA cloning of prophenoloxidase from the freshwater crayfish Pacifastacus leniusculus and its activation; Aspan A et al.; Prophenoloxidase (proPO), an enzyme that is the terminal component of the so-called proPO activating system, a defense and recognition system in crustaceans and insects, has been purified and cloned from a crayfish blood cell cDNA library . The deduced amino acid sequence codes for a polypeptide with a mass of 80,732 Da, which is close to 76 kDa, the apparent mass of the purified enzyme . proPO contains two copper atoms, and two putative copper-binding sites were found in the deduced amino acid sequence . Sequence comparisons show that these putative copper-binding sites are similar to the corresponding sites in arthropod hemocyanins and also, although the sequence similarities are less extensive, similar to tyrosinases from vertebrates and microorganisms . The purified enzyme is a typical tyrosinase because it hydroxylates monophenols and oxidizes o-diphenols but does not oxidize p-diphenols . If a homogeneous preparation of crayfish proPO were incubated with a homogeneous sample of the proPO activating enzyme, a serine proteinase, the cleavage of proPO by this trypsin-like enzyme was found to occur between Arg-176 and Thr-177. Tidsskr Nor Laegeforen, 1995 Feb 10, 115(4), 476 - 8 {Induced sputum . Indication for examination in Pneumocystis carinii pneumonia?}; von der Lippe E et al.; Induced sputum is a simple, rapid, and non-invasive technique for detection of Pneumocystis carinii in patients with Pneumocystis carinii pneumonia . In this study 31 patients were examined both with induced sputum and bronchoalveolar lavage . P . carinii was found in 24 patients . In 68% of the samples obtained by the induced sputum method the microorganism was found after Giemsa or methenamine silver staining . In 32% the diagnosis was established in the lavage fluid only . Induced sputum is indicated in moderate cases of P . carinii infection . Bronchoalveolar lavage has to be performed in suspected cases where staining of induced sputum is negative and when coinfection with other microbial agents is suspected. Gen Physiol Biophys, 1995 Feb, 14(1), 67 - 71 A simple method of determination of partition coefficient for biologically active molecules; Sersen F; A simple method is presented for the determination of partition coefficient of an effector between water environment and biological material, based on concentration-dependent effects . The method allows the determination of partition coefficients for biological objects such as algae, bacteria and other microorganisms. Mol Pharmacol, 1995 Feb, 47(2), 398 - 402 Structure-activity relationships of new heterocycle-containing bisphosphonates as inhibitors of bone resorption and as inhibitors of growth of Dictyostelium discoideum amoebae; Rogers MJ et al.; The mechanisms by which bisphosphonate drugs inhibit osteoclast-mediated bone resorption are unclear . Effects of bisphosphonates on cellular enzymes, metabolic pathways, and osteoclast morphology have previously been described and could culminate in a generalized cytotoxic effect or a decreased capacity of osteoclasts to resorb bone . Recent studies of the structure-activity relationship for the bisphosphonate side chain indicate, however, that at least the newer generations of nitrogen-containing bisphosphonates probably act by binding to a specific target at a site that is complementary in structure to the bisphosphonate side chain . We have previously proposed that such a target for bisphosphonates is also present in amoebae of the cellular slime mold Dictyostelium discoideum, because growth of this microorganism is inhibited by a wide range of bisphosphonates in a manner that closely reflects the antiresorptive potencies of the bisphosphonates in vivo . We have added support for this view by examining the potency towards Dictyostelium of bisphosphonates in which slight changes in the structure of the side chain or conformational restrictions to the side chain have marked effects on antiresorptive potency . The changes in the side chain that affected the in vivo antiresorptive potency of the bisphosphonates consistently affected in a similar manner the potency of the bisphosphonates as inhibitors of the growth of Dictyostelium amoebae . These observations confirm that bisphosphonate drugs have a molecular target that is common to both Dictyostelium amoebae and osteoclasts. J Bacteriol, 1995 Feb, 177(4), 1017 - 22 Proton pumping and the internal pH of yeast cells, measured with pyranine introduced by electroporation; Pena A et al.; The internal pH of yeast cells was determined by measuring the fluorescence changes of pyranine (8-hydroxy-1,3,6-pyrene-trisulfonic acid), which was introduced into the cells by electroporation . This may be a suitable procedure for the following reasons . (i) Only minor changes in the physiological status of the cells seemed to be produced . (ii) The dye did not seem to leak at a significant rate from the cells . (iii) Different incubation conditions produced large fluorescence changes in the dye, which in general agree with present knowledge of the proton movements of the yeast cell under different conditions . (iv) Pyranine introduced by electroporation seemed to be located in the cytoplasm and to avoid the vacuole, and therefore it probably measured actual cytoplasmic pH . (v) Correction factors to obtain a more precise estimation of the internal pH are not difficult to apply, and the procedure may be useful for other yeasts and microorganisms, as well as for the introduction of other substances into cells . Values for the cytoplasmic pHs of yeast cells that were higher than those reported previously were obtained, probably because this fluorescent indicator did not seem to penetrate into the cell vacuole. Infect Immun, 1995 Feb, 63(2), 430 - 6 Identification of a new intestinal spirochete with pathogenicity for chickens; Swayne DE et al.; Two intestinal spirochete isolates obtained from chickens with diarrhea were examined by electron microscopy, biochemical tests, rRNA gene restriction pattern analysis, and multilocus enzyme electrophoresis . One isolate (strain 91-1207/C1) was pathogenicity tested in vivo in chickens . The chicken spirochetes were morphologically indistinguishable from Serpulina innocens and Serpulina hyodysenteriae and phenotypically similar to S . innocens . However, the chicken spirochetes could be distinguished from S . innocens, S . hyodysenteriae, and other swine intestinal spirochetes by rRNA gene restriction pattern analysis and multilocus enzyme electrophoresis . In pathogenicity tests in 1-day-old chicks and 14-month-old hens, chicken spirochete 91-1207/C1 produced pale-yellow, watery cecal contents and mild lymphocytic typhlitis . These findings support the conclusion that avian intestinal spirochetes can be pathogenic to commercial poultry and that the microorganisms are different from intestinal spirochetes that infect pigs. J Ind Microbiol, 1995 Feb, 14(2), 169 - 77 Metal oxidoreduction by microbial cells; Wakatsuki T; For many organisms, some heavy metals in external media are essential at low concentrations but are toxic at high concentrations . Strongly toxic heavy metals are toxic even at low concentrations . Recently, it was proven that changes of valencies of Fe, Cu and Mn were necessary for these metals to be utilized by organisms, especially microorganism . The valencies of Hg and Cr are changed by reducing systems of cells in the process of detoxifying them . Thus, the processes of oxidoreduction of these metals are important for biological systems of metal-autoregulation and metal-mediated regulation . Metal ion-specific reducing enzyme systems function in the cell surface layer of microorganisms . These enzymes require NADH or NADPH as an electron donor and FMN or FAD as an electron carrier component . Electron transport may be operated by transplamsa-membrane redox systems . Metal ion reductases are also found in the cytoplasm . The affinities of metal ions to ligand residues change with the valence of the metal elements and mutual interactions of various metal ions are important for regulation of oxidoreduction states . Microorganisms can utilize essential metal elements and detoxify excess metals by respective reducing enzyme systems and by regulating movement of heavy metal ions. Cell Biophys, 1995 Feb, 26(1), 45 - 55 The electrokinetic surface of five enteropathogenic Escherichia coli serogroups; Mangia AH et al.; The surface ionogenicity of five enteropathogenic Escherichia coli serogroups (O111:H2, O111:H12, O125:H9, O119:H6, and O26:H11) was investigated by electrokinetical approaches . All of the studied surfaces are negatively charged with their mean values of zeta potential (ZP) varying from -9.0 (O26:H11) to -11.9 mV (O111:H2) . The populational behavior of the all bacteria are similar since very high ZP values varying from -26 to -30 mV were obtained in experiments carried out with the slip plane calculated at 6.83 nm from the cell surface . All the surfaces are extremely acidic, because the isoelectrophoretic points are localized at pH values below 3.0 . Treatment of the microorganisms with neuraminidase did not alter their surface anionogenicity, while treatment with trypsin or phospholipase C reduced their negative charge. Bioessays, 1995 Feb, 17(2), 109 - 17 Phagocytosis; Brown EJ; Phagocytosis is the process of recognition and engulfment of microorganisms or tissue debris that accumulate during infection, inflammation or wound repair . This ingestion, which is performed most efficiently by migrating, bone marrow-derived cells called 'professional phagocytes', is essential for successful host defense . Ingestion results when an invading microorganism is recognized by specific receptors on the phagocyte surface and requires multiple, successive interactions between the phagocyte and the target . Each of these interactions results in a signal transduction event, which is confined to the membrane and cytoskeleton around the ligated receptor and which is required for successful phagocytosis . Many molecules found at sites of inflammation or infection stimulate phagocytosis, so that efficient ingestion is confined to the site of infection or inflammation, which in turn limits the proinflammatory and tissue-destructive processes that accompany phagocytosis . This review summarizes current understanding of this critical component of host defense and of its regulation. Clin Infect Dis, 1995 Feb, 20(2), 461 - 6 Notes on the early history of infective endocarditis and the development of an experimental model; Contrepois A; Experimental models of infective endocarditis antedate Garrison and Freedman's work in 1970 . The hypothesis of the role of parasites (microorganisms) microscopically observed in vegetations and cardiac valves of patients with endocarditis was first put forth by Winge in Sweden in 1869 . Winge's work led Klebs and Rosenbach in Germany to establish, between 1878 and 1881, an animal model of experimental endocarditis in which the aortic valves of rabbits were perforated with a metallic probe (loaded with septic material) introduced through the carotid artery . Ten years after Winge's work, Pasteur emphasized the importance of bacteriologic "blood cultures." During the period 1881-1886, Netter and Grancher (Pasteur's associates) introduced a method for drawing aseptic blood samples from patients with clinical endocarditis and performing bacteriologic blood cultures . In Vienna in 1885-1886, Orth, Weichselbaum, and Wyssokowitsch further developed Rosenbach's procedure of inducing experimental endocarditis by injecting material from a bacterial culture into a rabbit's ear vein . The development of an experimental model of endocarditis by investigators in the latter part of the nineteenth century provided anatomopathological and bacteriologic data that in turn led to a better understanding of infective endocarditis. Clin Infect Dis, 1995 Feb, 20(2), 291 - 5 The practice of infectious diseases in the 1990s: the Canadian experience; Schlech WF 3rd; A survey of the members of the Canadian Infectious Disease Society was carried out to determine the content of an infectious diseases consultative practice in the 1990s . Respondents were asked to identify all new inpatient, outpatient, and telephone consultations during a 1-week period in 1990 . Consultations were categorized by the infectious disease syndrome of the patient and by the microorganism that was identified . Bacterial infections were the most common cause of inpatient consultations, while viral infections were more common in outpatients . Consultations for parasitic infections were primarily for Pneumocystis carinii pneumonia related to infection with the human immunodeficiency virus (HIV) . "Newer" infectious disease syndromes such as chronic fatigue syndrome, toxic shock syndrome, and Lyme disease were all represented in the responses for the 1-week study period . The significant impact of HIV infection on the overall consultative load suggests that there will be a continuing need for newly trained infectious disease consultants into the 21st century. Infusionsther Transfusionsmed, 1995 Feb, 22(1), 31 - 5 {Detection and side effects of isoantibodies in intravenously administered immunoglobulin preparations}; Strobel E et al.; BACKGROUND: Intravenous immunoglobulins (IvIg) contain not only the declared antibodies against pathogenic microorganisms, but also all the other antibodies of the blood donors, e.g . against erythrocytic antigens . MATERIALS AND METHODS: We tested 14 IvIg from 7 manufacturers (a total of 40 charges) for isoantibodies and irregular antibodies . To improve the reading of our tests we used the gel centrifugation method (ID-Microtyping-System, Fa . Diamed, Bensheim, Germany) . RESULTS: The highest isoantibody titers were (in 8 charges) 1:32 or 1:64 in the Liss-Coombs test . Irregular antibodies were found in 5 IvIg (maximal titer 1:8) . CONCLUSIONS: Isoantibodies in the IvIg can influence blood group serologic tests . With an example of a newborn who had received IvIg we point to the potential danger of misinterpretation of a positive direct antiglobulin test after administration of IvIg . Therefore we recommend to carry out the direct antiglobulin test before administration of IvIg and to examine all eluates after a positive direct Coombs test not only with 0 RBCs but also with A or B RBCs of the AB0 blood group of the patient. Ceska Gynekol, 1995 Feb, 60(1), 25 - 30 {Cytodiagnosis and premature birth in light of the Bethesda system}; Kobilkova J et al.; 1 . Evaluation of cytological cervico-vaginal smears by the Bethesda system enlisted cytodiagnostics among important laboratory methods which can be used also in risk pregnancies . 2 . Vaginal cytology makes it possible to test at the same time the hormonal situation during pregnancy, which reflects the placental function, and to evaluate also the vaginal biocenosis . 3 . The authors provided evidence that the large number of superficial cells on the cytological smear (more than 10%) is associated with low oestriol and pregnandiol levels which are warning signs of the approaching termination of pregnancy . 4 . By the action of microorganisms on the vaginal epithelium typical morphological changes develop in the cell nucleus and in the cytoplasm . By polychromatic staining also the causal agents of inflammations and infections threatening the mother and foetus are apparent . 5 . The authors assume that cytological examination and evaluation according to the Bethesda system should be included in the complex of antenatal examinations also in women without clinical symptoms of premature delivery or without signs of vaginal infection. Inflammation, 1995 Feb, 19(1), 101 - 18 Synergistic effects among oxidants, membrane-damaging agents, fatty acids, proteinases, and xenobiotics: killing of epithelial cells and release of arachidonic acid; Ginsburg I et al.; The assumption that cellular injury induced in infectious and in inflammatory sites might be the result of a well-orchestrated, synergistic "cross-talk" among oxidants, membrane-damaging agents, proteinases, and xenobiotics was further investigated in a tissue culture model employing monkey kidney epithelial cells (BGM) labeled either with 51 chromium or {3H}arachidonate . The cells could be killed in a synergistic manner following exposure to combinations among H2O2 and the following membrane-damaging agents: streptolysins S (SLS) and O (SLO), poly-D-lysine, arachidonic acid, eicosapentanoic acid, arachidic acid, lysophosphatidylcholine, lysophosphatidylinositol, lysophosphatidylglycerol, ethanol, and sodium taurocholate . Peroxyl radical (ROO) generated by azobisdiamidinopropane dihydrochloride (AAPH) further enhanced cell killing induced by SLS, SLO, and nitroprusside when combined with H2O2 and trypsin . BGM cells labeled either with chromium or with tritiated arachidonate, which had been treated with increasing concentrations of sodium nitroprusside (a donor of NO) and with subtoxic amounts of SLS and H2O2, were also killed in a synergistic manner and also lost a substantial amounts of their arachidonate label . Both cell killing and the release of membrane lipids were totally inhibited by hemoglobin (an NO scavenger) but not by methylene blue, an antagonist of NO2-BGM cells that had been treated with increasing concentrations of taurocholic acid were killed in a synergistic manner by a mixture of subtoxic amounts of ethanol, H2O2, and crystalline trypsin (quadruple synergism) . Normal human serum possessing IgM complement-dependent cytotoxic antibodies against Ehrlich ascites tumor cells were killed in a dose-dependent fashion . Cell killing was doubled by the addition of H2O2 . Cell killing and the release of membrane lipids by all the mixture of agonists tested were both strongly inhibited by the antioxidants catalase, Mn2+, vitamin A, and by fresh carrot juice . It appears that in order to overcome the antioxidant capacities of the epithelial cells, a variety of membrane-damaging agents had to be present in the reaction mixtures . Taken together, it might be speculated that the killing of mammalian cells in infectious and in inflammatory sites is a synergistic phenomenon that might be inhibited by antagonizing the cross-talk among the various proinflammatory agonists generated by microorganisms by activated phagocytes or by combinations among these agents . Our studies might also open up new approaches to the assessment of the toxicity of xenobiotics and of safe drugs to mammalian cells by employing tissue culture techniques. Int J Immunopharmacol, 1995 Feb, 17(2), 133 - 39 Low molecular weight immunomodulators produced by microorganisms; Ishizuka M et al.; In order to develop a new class of low molecular weight immunomodulators for the treatment of incurable diseases involving cancer, hematologic diseases and inflammation, we have sought cytokine inducers and inhibitors of cell adhesion to the extracellular matrix among the low molecular compounds produced by microorganisms . Cytogenin, cytoblastin (a monokine inducer), conagenin (a lymphokine inducer) and delaminomycins and IC-101 (inhibitors of cell adhesion to extracellular matrices) have been recently found in our institute . In this report, we describe the principles of screening and structures, and discuss their biological activities. Eur J Vasc Endovasc Surg, 1995 Feb, 9(2), 143 - 51 Histopathological characteristics of explanted human prosthetic arterial grafts: implications for the prevention and management of graft infection; Olofsson P et al.; OBJECTIVE: to study the histopathological characteristics of prosthetic vascular graft infection . DESIGN: prospective clinical study over 2 years . SETTING: University Hospital . MATERIALS: 36 infected and 29 uninfected (control) chronically implanted vascular prostheses (half aortic) were removed and 352 sections prepared . CHIEF OUTCOME MEASURES: light microscopy (multiple stains), scanning electron microscopy (SEM), and multiple culture techniques to identify characteristics of healing, infection, and microorganisms . MAIN RESULTS: Acute inflammation (AI) (neurophils, granulocytes and necrosis) were seen in 75% of infected grafts, were most prominent in the perigraft tissue and rarely seen on the luminal surface . These were usually well localised, leaving the remainder of a graft well incorporated with no signs of infection . In 25% of clinically infected, culture-positive grafts there was no significant acute inflammation . Chronic inflammation (CI) (macrophages, lymphocytes, monocytes, giant cells) was seen in 70% of both control and infected grafts . In 50% of both groups a significant lymphocytic population was composed exclusively of T-lymphocytes suggesting a true host vs graft response . Unincorporated chronically implanted grafts (> 1 yr) were seen with equal frequency in the two groups although more diffusely unincorporated grafts were infected . Microorganisms were cultured from 23 infected grafts (64%) and were, at microscopy, mostly found outside the graft and nerves on the luminal side . CONCLUSIONS: This data cast doubt on criteria commonly used to distinguish graft infections and host vs . graft reactions from normal graft healing . Acute and chronic inflammation are not predictive of infection. Environ Health Perspect, 1995 Feb, 103 Suppl 1, 53 - 8 Trace metal mobilization in soil by bacterial polymers; Chen JH et al.; Enhanced transport of trace metal in porous media can occur in the presence of a ligand or "carrier" that has a high affinity for binding the pollutant, is dispersed and mobile in the soil environment, is recalcitrant with respect to microbial degradation, and is acceptable to the public . These aspects of the facilitated transport to trace metals are discussed with respect to a naturally occurring carrier: extracellular polymers of bacterial origin . The literature is reviewed regarding the production and composition of bacterial extracellular polymers, the processes relevant to the facilitated transport of trace metals in soil by bacterial polymers, and potential for transformation of polymers in soils by microbial degradation . Model calculations of contaminant retardation are presented for the case of polymer-mediated transport of cadmium in a sandy aquifer material . The available information suggests that extracellular polymers can bind metal ions and are mobile in the soil environment . Extracellular polymers also appear to be relatively slowly degraded by soil microorganisms . These properties and the supporting model calculations indicate that extracellular polymers of bacterial origin merit consideration as agents that may be applied to contaminated soils to enhance trace metal mobility. Appl Environ Microbiol, 1995 Feb, 61(2), 407 - 12 Detection of Legionella species in reclaimed water and air with the EnviroAmp Legionella PCR kit and direct fluorescent antibody staining; Palmer CJ et al.; Reclaimed water is an important resource for areas with inadequate water supplies . However, there have been few studies on the variety of microorganisms found in this type of water, since typically reclaimed water is examined only for the presence of coliform bacteria . Many microorganisms, including the legionellae, are known to be more resistant to chlorine than are coliform bacteria . Previously, we detected > 10(3) Legionella cells per ml in primary and secondary sewage effluents and observed no significant reduction in population numbers throughout the treatment process . In this study, we detected Legionella spp . in chlorinated effluent by using an EnviroAmp Legionella PCR kit and direct fluorescent antibody (DFA) staining . However, we were not able to isolate Legionella spp . from either natural or seeded reclaimed water samples . This suggests that the Legionella spp . detected by the PCR and DFA methods may be injured or viable but nonculturable after exposure to the high residual chlorine levels typically found in this type of water source . The numbers of coliform bacteria were low (< 2 cells per 100 ml) in most reclaimed water samples and were not correlated with the presence or absence of Legionella spp . We also collected air samples from above a secondary aeration basin and analyzed them by using the PCR, DFA, and plate culture methods . Legionella spp . were detected in the air obtained from above the secondary basin with all three methods . We concluded that the PCR was superior to the culture and DFA methods for detecting Legionella spp . in environmental water samples. Singapore Med J, 1995 Feb, 36(1), 107 - 9 Tuberculosis and invasive pulmonary aspergillosis in a young woman with a myelodysplastic syndrome; Kueh YK et al.; A 29-year-old Chinese woman developed pyrexia, multiple skin abscesses and bilateral fine nodular lung infiltrates about 3 months after the commencement of therapy for idiopathic thrombocytopenic purpura (ITP) . Pseudomonas aeroginosa was isolated from the abscesses but multiple blood and sputum cultures, as well as a broncho-alveolar lavage did not yield any microorganisms . The persistence of fever and pulmonary infiltrates warranted an open lung biopsy which provided a definitive diagnosis of tuberculous-aspergillus granulomatous lung disease . Bone marrow re-examination revised the primary haematological disorder to that of a trisomy 8 associated myelodysplastic syndrome. Pediatr Allergy Immunol, 1995 Feb, 6(1), 20 - 3 Ontogeny of human mannan-binding protein, a lectin of the innate immune system; Thiel S et al.; Mannan-binding protein (MBP) is a member of the collectins . These lectins are composed of polypeptide chains which contains a collagen-like region and a calcium dependent carbohydrate recognition domain (named a C-type CRD) . MBP binds via the CRD to carbohydrate structures on microorganisms . MBP can activate the complement system when bound to carbohydrate . MBP is thus thought to play a role in the defence against microorganisms . The present report describes the ontogeny of MBP . The level of MBP increase during the first 3 months of life, at which time a stable level is reached, comparable to that seen in adults . On average, the level of MBP at term was 37% of the post 3-month level . Measurements on infants born prematurely showed a 3-fold increase in MBP concentration from the time of birth at around 30 weeks from conception to the 10th week of life. FASEB J, 1995 Feb, 9(2), 200 - 9 Free radicals and phagocytic cells; Rosen GM et al.; Phagocytes mediate their innate immunological response by releasing products that damage invading microorganisms . These products include proteins such as lysozyme, peroxidases, and elastase as well as reactive oxygen species such as superoxide, hydrogen peroxide, hypohalous acid, and hydroxyl radical . Although it is clear that many phagocytic secretory products have direct cytotoxic potential, understanding is limited of how multiple products interact to generate and modulate the cytotoxic response . This review focuses on recent findings that elucidate the biochemical nature of secretory product interaction in the formation of free radicals, particularly the highly reactive hydroxyl radical . The possible role of these reactions in phagocyte microbicidal activity and inflammatory tissue injury is discussed. Insect Mol Biol, 1995 Feb, 4(1), 23 - 9 Molecular analysis of the endosymbionts of tsetse flies: 16S rDNA locus and over-expression of a chaperonin; Aksoy S; Based on 16S rDNA sequence comparison, intracellular mycetome-associated endosymbionts (P-endosymbionts) of tsetse flies (Diptera: Glossinidae) form a distinct lineage within the gamma-3 subdivision of proteobacteria, related to the free-living bacterium Escherichia coli, midgut S-endosymbionts of various insects including tsetse flies, and to the P-endosymbiont lineage of aphids, Buchnera aphidicola . Gene organization and expression of several loci in intracellular microorganisms have revealed differences from free-living bacteria . This study analyses two of these characteristics in tsetse endosymbionts; the copy number and gene organization of rDNA operations and the nature of the abundant protein(s) synthesized by these microorganisms . Results indicate that Glossina morsitans morsitans S-endosymbionts have multiple (seven) rDNA operons coding for 16S (rrs) followed by 23S (rrl) gene sequences, whereas tsetse P-endosymbionts have a single, similarly organized rDNA operon . In tsetse mycetocytes in vitro, P-endosymbionts synthesize a predominant protein of 60 kDa in size (p60) which by Western blot analysis shows immunological cross-reactivity with the abundant 63 kDa (p63) protein of B . aphidicola . p63 (also referred to as symbionin) has been characterized as a molecular chaperone, structurally and functionally similar to the groEL protein of E . coli . Under in vitro conditions, tsetse S-endosymbionts synthesize high levels of a similarly-sized protein that cross-reacts with p63 chaperonin . Antisera against the tsetse p60 protein also recognizes p63 protein of B . aphidicola, suggesting that the abundant tsetse endosymbiont protein is a chaperonin. Transplantation, 1995 Jan 27, 59(2), 234 - 40 Abdominal multivisceral transplantation; Todo S et al.; Under FK506-based immunosuppression, 13 abdominal multivisceral transplantations were performed in 6 children and 7 adults . Of the 13 recipients, 7 (53.8%) are alive and well with functioning grafts after 9 to 31 months . Six recipients died: three from PTLD, one from rejection, one from sepsis, and one from respiratory failure . In addition to rejection, postoperative complications occurring in more than isolated cases included PTLD (n = 6), abdominal abscess formation (n = 5), pancreatitis (n = 3), and ampullary dysfunction (n = 2) . In addition, infection by enteric microorganisms was common during the early postoperative period . Currently, all 7 survivors are on an oral diet and have normal liver function . Two recipients (one insulin-dependent) require antidiabetes treatment, in one case following distal pancreatectomy and in the other after two episodes of pancreatic rejection . Thus, abdominal multivisceral transplantation is a difficult but feasible operation that demands complex and prolonged posttransplantation management . It is not yet ready for application and awaits a better strategy of immune modulation. J Biol Chem, 1995 Jan 20, 270(3), 1308 - 14 Biosynthetic modulation of sialic acid-dependent virus-receptor interactions of two primate polyoma viruses; Keppler OT et al.; Sialic acids are essential components of the cell surface receptors of many microorganisms including viruses . A synthetic, N-substituted D-mannosamine derivative has been shown to act as precursor for structurally altered sialic acid incorporated into glycoconjugates in vivo (Kayser, H., Zeitler, R., Kannicht, C., Grunow, D., Nuck, R., and Reutter, W . (1992) J . Biol . Chem . 267, 16934-16938) . In this study we have analyzed the potential of three different sialic acid precursor analogues to modulate sialic acid-dependent virus receptor function on different cells . We show that treatment with these D-mannosamine derivatives can result in the structural modification of about 50% of total cellular sialic acid content . Treatment interfered drastically and specifically with sialic acid-dependent infection of two distinct primate polyoma viruses . Both inhibition (over 95%) and enhancement (up to 7-fold) of virus binding and infection were observed depending on the N-acyl substitution at the C-5 position of sialic acid . These effects were attributed to the synthesis of metabolically modified, sialylated virus receptors, carrying elongated N-acyl groups, with altered binding affinities for virus particles . Thus, the principle of biosynthetic modification of sialic acid by application of appropriate sialic acid precursors to tissue culture or in vivo offers new means to specifically influence sialic acid-dependent ligand-receptor interactions and could be a potent tool to further clarify the biological functions of sialic acid, in particular its N-acyl side chain. Nature, 1995 Jan 19, 373(6511), 264 - 8 Penicillin acylase has a single-amino-acid catalytic centre; Duggleby HJ et al.; Penicillin acylase (penicillin amidohydrolase, EC 3.5.1.11) is widely distributed among microorganisms, including bacteria, yeast and filamentous fungi . It is used on an industrial scale for the production of 6-aminopenicillanic acid, the starting material for the synthesis of semi-synthetic penicillins . Its in vivo role remains unclear, however, and the observation that expression of the Escherichia coli enzyme in vivo is regulated by both temperature and phenylacetic acid has prompted speculation that the enzyme could be involved in the assimilation of aromatic compounds as carbon sources in the organism's free-living mode . The mature E . coli enzyme is a periplasmic 80K heterodimer of A and B chains (209 and 566 amino acids, respectively) synthesized as a single cytoplasmic precursor containing a 26-amino-acid signal sequence to direct export to the cytoplasm and a 54-amino-acid spacer between the A and B chains which may influence the final folding of the chains . The N-terminal serine of the B chain reacts with phenylmethylsulphonyl fluoride, which is consistent with a catalytic role for the serine hydroxyl group . Modifying this serine to a cysteine inactivates the enzyme, whereas threonine, arginine or glycine substitution prevents in vivo processing of the enzyme, indicating that this must be an important recognition site for cleavage . Here we report the crystal structure of penicillin acylase at 1.9 A resolution . Our analysis shows that the environment of the catalytically active N-terminal serine of the B chain contains no adjacent histidine equivalent to that found in the serine proteases . The nearest base to the hydroxyl of this serine is its own alpha-amino group, which may act by a new mechanism to endow the enzyme with its catalytic properties. Dtsch Med Wochenschr, 1995 Jan 5, 120(1-2), 23 - 8 {Disseminated extrapulmonary tuberculosis in idiopathic CD4-lymphocytopenia}; Neukirch B et al.; A previously healthy, now 42-year-old man suddenly fell ill with bouts of septic fever up to 39.5 degrees C, sweats and weight loss without any demonstrable organ involvement . Physical examination on hospitalization 3 weeks after onset of the illness was unremarkable . Blood sedimentation rate at one hour was 123 mm . There was also a moderate increase in gamma-GT and alkaline phosphatase . Routine bacteriological and serological tests failed to discover a causative microorganism . After imaging tests had provided first indication of splenic and hepatic involvement, biopsies of these two organs demonstrated disseminated epithelioid granulomas and Langhans giant cells . Staining and culturing of pelvic crest biopsy tissue showed evidence of Mycobacterium tuberculosis, but there was no evidence of pulmonary involvement . In addition to four-drug tuberculostatic treatment the patient was given glucocorticoids for several weeks to control the fever bouts . Persistent CD4+ T-lymphocytopenia was demonstrated as the cause of the entirely extrapulmonary tuberculosis in this HIV-negative patient . This is an only recently described and so far unexplained syndrome. Nature, 1995 Jan 5, 373(6509), 72 - 4 Increased male fertility in Tribolium confusum beetles after infection with the intracellular parasite Wolbachia; Wade MJ et al.; The cytoplasmically inherited microorganism Wolbachia pipientis behaves like a sexually selected trait in its host, the flour beetle Tribolium confusum, enhancing male fertility at the expense of female fecundity . Here we show that infected females have fewer offspring than uninfected females but infected males have a large fertility advantage over uninfected males within multiply-inseminated infected or uninfected females . The male fertility effect accelerates the spread of the Wolbachia through the host population and expands the initial opportunity for hitch-hiking of host nuclear genes . Sperm competition in a host, mediated by endosymbionts, has not been previously described. Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 9 - 13 The chemistry of poisons in amphibian skin; Daly JW; Poisons are common in nature, where they often serve the organism in chemical defense . Such poisons either are produced de novo or are sequestered from dietary sources or symbiotic organisms . Among vertebrates, amphibians are notable for the wide range of noxious agents that are contained in granular skin glands . These compounds include amines, peptides, proteins, steroids, and both water-soluble and lipid-soluble alkaloids . With the exception of the alkaloids, most seem to be produced de novo by the amphibian . The skin of amphibians contains many structural classes of alkaloids previously unknown in nature . These include the batrachotoxins, which have recently been discovered to also occur in skin and feathers of a bird, the histrionicotoxins, the gephyrotoxins, the decahydroquinolines, the pumiliotoxins and homopumiliotoxins, epibatidine, and the samandarines . Some amphibian skin alkaloids are clearly sequestered from the diet, which consists mainly of small arthropods . These include pyrrolizidine and indolizidine alkaloids from ants, tricyclic coccinellines from beetles, and pyrrolizidine oximes, presumably from millipedes . The sources of other alkaloids in amphibian skin, including the batrachotoxins, the decahydroquinolines, the histrionicotoxins, the pumiliotoxins, and epibatidine, are unknown . While it is possible that these are produced de novo or by symbiotic microorganisms, it appears more likely that they are sequestered by the amphibians from as yet unknown dietary sources. Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 75 - 82 Chemical ecology: a view from the pharmaceutical industry; Caporale LH; Biological diversity reflects an underlying molecular diversity . The molecules found in nature may be regarded as solutions to challenges that have been confronted and overcome during molecular evolution . As our understanding of these solutions deepens, the efficiency with which we can discover and/or design new treatments for human disease grows . Nature assists our drug discovery efforts in a variety of ways . Some compounds synthesized by microorganisms and plants are used directly as drugs . Human genetic variations that predispose to (or protect against) certain diseases may point to important drug targets . Organisms that manipulate molecules within us to their benefit also may help us to recognize key biochemical control points . Drug design efforts are expedited by knowledge of the biochemistry of a target . To supplement this knowledge, we screen compounds from sources selected to maximize molecular diversity . Organisms known to manipulate biochemical pathways of other organisms can be sources of particular interest . By using high throughput assays, pharmaceutical companies can rapidly scan the contents of tens of thousands of extracts of microorganisms, plants, and insects . A screen may be designed to search for compounds that affect the activity of an individual targeted human receptor, enzyme, or ion channel, or the screen might be designed to capture compounds that affect any step in a targeted metabolic or biochemical signaling pathway . While a natural product discovered by such a screen will itself only rarely become a drug (its potency, selectivity, bioavailability, and/or stability may be inadequate), it may suggest a type of structure that would interact with the target, serving as a point of departure for a medicinal chemistry effort--i.e., it may be a "lead." It is still beyond our capability to design, routinely, such lead structures, based simply upon knowledge of the structure of our target . However, if a drug discovery target contains regions of structure homologous to that in other proteins, structures known to interact with those proteins may prove useful as leads for a medicinal chemistry effort . The specificity of a lead for a target may be optimized by directing structural variation to specificity-determining sites and away from those sites required for interaction with conserved features of the targeted protein structure . Strategies that facilitate recognition and exploration of sites at which variation is most likely to generate a novel function increase the efficiency with which useful molecules can be created. Proc Natl Acad Sci U S A, 1995 Jan 3, 92(1), 56 - 61 The chemistry of signal transduction; Clardy J; Several disciplines, including chemical ecology, seek to understand the molecular basis of information transfer in biological systems, and general molecular strategies are beginning to emerge . Often these strategies are discovered by a careful analysis of natural products and their biological effects . Cyclosporin A, FK506, and rapamycin are produced by soil microorganisms and are being used or considered as clinical immunosuppressive agents . They interrupt the cytoplasmic portion of T-cell signaling by forming a complex with a binding protein--FKBP12 in the case of FK506 and rapamycin and cyclophilin A (CyPA) in the case of cyclosporin A (CsA) . This complex in turn inhibits a protein target, and the best understood target is calcineurin, which is inhibited by FK506-FKBP12 and CyPA-CsA . Mutational and structural studies help define how FK506-FKBP12 interacts with calcineurin, and the results of these studies are summarized . The existence of strong FK506-FKBP12 binding suggests that FK506 is mimicking some natural ligand for FKBP12 . Synthetic and structural studies to probe this mimicry are also described. Acta Cient Venez, 1995, 46(2), 135 - 9 {Production of an acid extract of rice straw}; Zamora R et al.; The chemical composition of rice straw was determined by means of standard analytical procedures . The material showed an adequate content of potentially assimilable carbohydrates for the growth of microorganisms . The optimum result of the rice straw treatment corresponds to a particle size of 60 mesh mixed with 5% H2SO4 in a weight: volume relation of 1:10 and submitted to a temperature of 121 degrees C . Under these conditions a rice straw's acid extract was obtained, containing 20 g/lt of total sugars and 15 g/lt of reducing sugars . This content of sugars is enough to support the growth of microorganisms in aerobic conditions. Drug Metabol Drug Interact, 1995, 12(3-4), 171 - 87 Plant cytochromes P450: an overview; Durst F et al.; Cytochromes P450 from higher plants share many general characteristics with those from animals and microorganisms . There are now 20 known P450 gene families in plants, with the number rapidly increasing . Many of these enzymes catalyze reactions in the secondary metabolic pathways of higher plants . The sheer number of plant species and the variety of these many pathways together result in the diverse enzyme chemistry available from P450s in the plant kingdom . Highlights of recent findings and of the contents of this journal issue are summarized. Scanning Microsc, 1995, 9(4), 1121 - 6; discussion 1126 Alterations in intestinal transport of oxalate in disease states; Hatch M et al.; Normally, absorption of oxalate from dietary sources can occur in all segments of the intestinal tract . However, alterations in both the magnitude and direction of oxalate fluxes across the intestine can occur in disease states . In enteric hyperoxaluria, enhanced absorption of oxalate by the large intestine is caused by increased permeability of a shunt conductance induced by malabsorbed bile salts and fatty acids . In this condition, the contribution of a paracellular passive flux of oxalate moving along its electrochemical gradient will predominate when intraluminal concentrations of free oxalate are high . In contrast, in chronic renal failure, secretion of oxalate can occur across both small and large intestine thereby facilitating extrarenal elimination with subsequent degradation by mucosal substrate-specific microorganisms . Clearly, in recent studies of oxalate transport, the intestine has emerged with an integral role in mass balance of oxalate in health and disease. Rev Esp Cardiol, 1995, 48 Suppl 7, 96 - 107 {Infectious complications in patients undergoing a heart transplant}; Bouza E et al.; Infectious complications are, with rejection, the main cause of morbidity and mortality in heart transplantation recipients . Adequate management of these patients requires an adequate knowledge of risk factors, of most common infectious syndromes and of relevant microorganism, as long as of their resistance pattern . Among the first group, we may mention lower respiratory tract infections, mediastinitis and meningitis, and among the microorganisms, Citomegalovirus, Aspergillus and Toxoplasma gondii . The impressive development of diagnostical techniques and of prophylactic and therapeutical possibilities suggest the convenience of a multidisciplinar approach to these complications. J Health Polit Policy Law, 1995 Winter, 20(4), 1001 - 24 Miasma and "social factors" in disease causality: lessons from the nineteenth century; Tesh SN; Conventional public health wisdom holds that the end of the nineteenth century saw a dramatic change in beliefs about what causes disease, as early convictions about the importance of broad social factors gave way to a concentration on microorganisms . I argue, however, that in both the middle and late nineteenth century nearly everyone, professionals and laypeople alike, saw disease causality in terms of precise, invisible entities, and that prevention policies were as reductionist and narrow as the available technology would allow . My argument is based on a rereading of the primary documents that other scholars have seen as supporting the idea of two distinct public health periods, and on a new interpretation of the revisionist history that questions the idea . I suggest that health policy analysts today are too vague about the meaning of "social factors" and that disease prevention policies might be better if the term was clarified. Chir Ital, 1995, 47(2), 14 - 24 {The intestine: a central organ in the pathogenesis of septic complications in acute pancreatitis}; Gianotti L et al.; Despite the array of new diagnostic and therapeutic tools, acute pancreatitis remains a critical condition with a high rate of septic morbidity and mortality . To date the main cause of death is still the occurrence of septic complications . In 80% the cases, the microorganisms responsible for infection are of enteric origin and in 30% of the patients with septic shock, no evident focus of infection is recognized . Bacterial translocation is increasingly accepted as the main cause of infection, sepsis and multiple organ failure in these critically ill patients . The mechanisms facilitating the loss of gut barrier function are overgrowth of enteric bacteria and damage to the intestinal mucosa . Pancreatitis-induced immunosuppression may allow the systemic spread of translocated organisms and subsequent severe septic sequelae. Adv Neuroimmunol, 1995, 5(3), 299 - 309 Morphine stimulates phagocytosis of Mycobacterium tuberculosis by human microglial cells: involvement of a G protein-coupled opiate receptor; Peterson PK et al.; Opiate-induced immunosuppression has been implicated in the pathogenesis of infections caused by a variety of microorganisms, including human immunodeficiency virus (HIV) . Although effects of opiates on lymphocyte function have been studied more extensively, morphine also has been shown to inhibit several functional activities of mononuclear phagocytes (e.g . chemotaxis, respiratory burst activity and phagocytosis) . Opiate addiction has been identified as a risk factor for clinical tuberculosis prior to the HIV epidemic, and macrophages are a key cell in the pathogenesis of Mycobacterium tuberculosis . Thus, the hypothesis was tested in the present study that morphine would suppress phagocytosis of M . tuberculosis by human microglial cells, the resident macrophages of the brain . Contrary to this hypothesis, treatment of human fetal microglial cell cultures with morphine (10(-8) M) was found to stimulate phagocytosis of nonopsonized M . tuberculosis H37Rv . The stimulatory effect of morphine was blocked by naloxone and the mu opiate receptor selective antagonist beta-funaltrexamine . Also, morphine-induced increase in phagocytic activity was markedly inhibited by pertussis toxin and was unaffected by cholera toxin, suggesting the mechanism of morphine's stimulatory effect on microglial cell phagocytosis involves a Gi protein-coupled mu opiate receptor . The results of this in vitro study support the concept that exogenous and endogenous opioids play an immunomodulatory role within the central nervous system through their interaction with G protein-coupled receptors on microglial cells. Adv Neuroimmunol, 1995, 5(4), 379 - 410 Nitric oxide in the liver: physiopathological roles; Suzuki H et al.; Many of the known roles of arginine (e.g . in immune function, wound healing, and protection against ammonia intoxication) are mediated by a metabolic pathway synthesising nitric oxide (NO) in the liver . Contrary to some of the current views, liver-produced NO may be basically beneficial, as it exerts both protective actions against tissue injury and cytotoxic effects on invading microorganisms, parasites, or tumor cells . An ongoing equilibrium between NO and other NO-reactive compounds (e.g . O2 and non-heme iron-sulphur-containing moieties) appears to be important in this respect, even under critical conditions . Thus, NO may prevent liver tissue harm from oxidant stress . Only when this putative counterbalance is upset by an uncontrolled, prolonged and/or massive production of NO, liver tissue damage may occur leading to hepatic inflammation or even tumor development . Moreover, the currently available data support the working hypothesis that hepatocytes partake not only to immunoregulatory processes, but even to immune defence mechanisms . Thus, the liver constitutes an excellent model for investigations into the crosstalks regulating the production of NO which take place among not only the various networks operating inside a single hepatic cell, but even the individual types of liver cells. Vestn Khir Im I I Grek, 1995, 154(3), 63 - 4 {The comparative characteristics of the efficacy of medium- and low-frequency ultrasound in treating the suppurative wound}; Iudin VA et al.; The investigation has been conducted to study the influence of middling and low-frequency ultrasound on the culture of standard microorganisms in vitro and in vivo and on the wound process in 26 patients . It has been shown that the middling ultrasound has a priority bactericidal effect upon the microorganisms and the wound infection . It also makes the process of depuration more active. Adv Exp Med Biol, 1995, 390, 211 - 6 An improved method for in vitro susceptibility testing of Trichomonas vaginalis; Bromke BJ et al.; A protocol is presented for in vitro susceptibility testing of Trichomonas vaginalis . A 100 ml culture of the microorganisms is prepared for inoculation into antibiotic dilutions and controls by centrifugation, washing with 10 mM HEPES (pH 6.2) plus 1.5 x 10(-1) M NaCl, a second centrifugation and a resuspension in the HEPES-saline buffer . Inclusion of the gelling agent carrageenan in the culture medium permits an ease of harvesting the trichomonads and a reproducible initial cell density of 1-4 x 10(4) cells per ml . Following inoculation, tubes with antibiotic dilutions and controls are incubated anaerobically at 35 degrees C for 48 h, which corresponds to late exponential phase . Inclusion of a negative control helps determine Minimum Lethal Concentration (MLC) values. Skin Pharmacol, 1995, 8(6), 319 - 25 Optimization of topical erythromycin formulations by ion pairing; Matschiner S et al.; Erythromycin (ERY) is used in the topical treatment of acne vulgaris . In order to decrease the amount of microorganisms markedly, the antibiotic must penetrate into the sebaceous follicles . Firstly, the aim of this study was to improve the lipophilicity of ERY by ion pairing . Secondly, a formulation with optimized penetration of the ion pair was developed . Thirdly, the optimized formulation was compared with formulations containing ethanol and with the commercial product Zineryt . The determination of lipophilicity was based on partition coefficients (PC) and on the penetration of ERY into a modified multilayer membrane system (MMS) . It was shown that the penetration of ERY into a lipophilic acceptor system was three times higher when ion pairing between ERY and octadecansulfonate was used in comparison with the penetration of the ERY base alone . The dosage of the antibiotic used can be markedly reduced by optimizing a vehicle for the ion pair. Rev Environ Contam Toxicol, 1995, 144, 1 - 93 Ecotoxicology of chlorpyrifos; Barron MG et al.; Chlorpyrifos is a broad-spectrum organophosphorothioate insecticide with a principal mechanism of toxicity by inactivation of acetylcholinesterase at nerve junctions . Unlike certain organochlorine pesticides, chlorpyrifos is relatively nonpersistent (Racke 1993), and its principal degradation products are less toxic than the parent chemical . Species sensitivity varies considerably across kingdom and phyla . In general, aquatic and terrestrial microorganisms and plants are tolerant to chlorpyrifos exposure . Aquatic invertebrates, particularly crustaceans and insect larvae, are sensitive to exposure: LC50s are generally less than 1 microgram/L, and no-observed-effect concentrations may be below 0.1 microgram/L in laboratory studies . Fish appear to be less sensitive, with LC50s generally between 1 and 100 micrograms/L and no-observed effect concentrations of approximately 0.5 microgram/L . In general, saltwater and freshwater organisms exhibit similar sensitivity to chlorpyrifos, considering the extreme phylogenetic and species differences in toxicity . Chlorpyrifos effects in aquatic ecosystems are complex because of the diversity of species assemblages and trophic interactions . In general, functional endpoints (e.g., community metabolism) are less sensitive than structural parameters of ecosystems (e.g., loss of sensitive species) . Ecosystem recovery is dependent on the interaction of a variety of factors including treatment timing and application dose, rate of dissipation, species assemblages, trophic structure, and the reproductive capacity and growth rate of susceptible and tolerant populations . Terrestrial species are relatively tolerant of chlorpyrifos exposure, although contact toxicity to sensitive terrestrial invertebrates may occur at concentrations of 0.1 microgram/insect . Amphibians, birds, and mammals show similar sensitivity to orally administered chlorpyrifos, with LD50s ranging from 8 to > 400 mg/kg body weight . Long-term chronic feeding studies in birds and mammals have shown no observed effect concentrations to be greater than 1 mg/kg food . In general, field studies have shown limited or no acute toxicity to amphibians, reptiles, birds, or mammals. J Enzyme Inhib, 1995, 9(4), 243 - 52 DMI-1, a new DNA methyltransferase inhibitor produced by Streptomyces sp . strain No . 560; Suzuki K et al.; A new inhibitor of DNA methyltransferase named DMI-1 has been discovered in the culture filtrate of Streptomyces sp . strain No . 560 . DMI-1 was purified by extraction with ethyl acetate followed by Diaion HP-20SS and silica gel column chromatography . The structure of DMI-1 was determined to be 8-methylpentadecanoic acid (C16H32O2) . DMI-1 is a novel inhibitor of methyltransferase isolated from microorganisms and is structurally different from sinefungin and A9145C which are structural analogs of S-adenosylmethionine (methyl donor) . DMI-1 was a strong inhibitor of N6-methyladenine-DNA methyltransferase (M . Eco RI, EC 2.1.1.72) in a noncompetitive manner and its inhibition depended on the pH and temperature in the assay media. Biochimie, 1995, 77(7-8), 651 - 60 Small G proteins and the neutrophil NADPH oxidase; Dagher MC et al.; The NADPH oxidase of phagocytic cells is a multimeric enzyme complex activated during phagocytosis . It catalyzes the production of the superoxide anion, precursor of many toxic oxygen metabolites involved in the defense against microorganisms . The enzyme becomes active after assembly on a membrane bound flavocytochrome b of cytosolic factors p47 phox, p67 phox and p40 phox and of low molecular mass GTP binding proteins . This paper reviews recent results concerning the role of two small G proteins, Rac and Rap 1A in oxidase activation . Native prenylated small G proteins are either in the form of a complex in which the GDP bound G protein is associated with a guanine nucleotide dissociation inhibitor, GDI, or in an active GTP bound form able to trigger the activity of its effector . Rac and Rho share a common GDI . As chemotaxis, under Rho control, and oxidase activation, under Rac control, show mutually exclusive signalling pathways, we propose a model where the GDI would switch from one pathway to the other by sequestering either Rac or Rho. Wien Med Wochenschr, 1995, 145(17-18), 385 - 9 {Cellular mechanisms of circadian clocks}; Roenneberg T et al.; The mechanisms of the biological clock are today being investigated in single neurons in cell culture or in unicellular and in other microorganisms . The results show that all components of this "endogenous clock" can be found at the cellular level . The cellular circadian program is controlled by a complex system of biochemical reactions, which can contain more than one circadian pacemaker and which comprises several feed-back loops at the input and the output side . This complex temporal program is a prerequisite for specialization and survival within the chrono-ecological niches of the "temporal space" day . It enables organisms on the one hand to adaptively react to environmental changes and thereby reaching transient independence of the external, physical time course; on the other side, it ensures that the endogenous day never runs out of synchrony with the solar day of the environment. Scand J Infect Dis, 1995, 27(5), 511 - 4 Cyclospora in patients with traveller's diarrhea; Gascon J et al.; Following the description in 1986 of a new enteropathogen called Cyanobacteria-like body (CLB), several outbreaks caused by this microorganism have been described . Since then several research teams have agreed to place CLB in the genus Cyclospora and to establish the epidemiological, pathogenical and clinical features of the illness . This paper describes and assesses those features in 20 travellers diagnosed with CLB and reviews the main literature concerning this enteropathogen . CLB was found in 2.8% of all cases of traveller's diarrhea in our series. Arch Tierernahr, 1995, 48(3), 245 - 56 {In vitro studies on glycerol transformation by rumen microorganisms}; Bergner H et al.; Rumen fluid from sheep (non adapted to glycerol) was incubated up to six hours under anaerobic conditions with buffer and mineral solution . Wheat starch was added as substrate in an amount of 1g DM per vessel . Glycerol was additionally admitted to rumen fluid in amounts of 5 to 50% of starch . Carrier-free 14C-glycerol (1.3-labelled) or 15N-labelled NH4Cl were added to different incubation vessels . The disappearance rate of glycerol depended from the amount of added glycerol and incubation time . More than 90% of glycerol disappeared in 2 hours (5% addition), 4 hours (10% addition) and 6 hours (15 to 25% addition) respectively . The sum of volatile fatty acids elevated significant with a higher glycerol addition and 6 hours incubation time . The concentration of propionic acid increased also in dependence of the added glycerol amount and the longer incubation time . The proportion of acetic acid to propionic acid changed from high values (3.5 to 4.0, without glycerol) to the lowest value from 2.5 after 6 hours incubation time and 25% glycerol addition . The most radioactivity of added 14C-glycerol was found in propionic acid and only up to 11% in CO2 . 14C-radioactivity was not detected in methane, lactic acid and acetic acid respectively . The 15N-labelling of TCA-precipitable N-fraction was not influenced by glycerol supplementation but the 15N-incorporation in the bacterial nitrogen fraction was lower in the vessels with glycerol. Crit Rev Neurobiol, 1995, 9(2-3), 137 - 62 Neurovirulence of pseudorabies virus; Card JP et al.; Virulence is defined as the relative capacity of a microorganism to overcome the defense mechanisms of the host organism and thereby cause disease . Virally induced virulence is usually quantitated by measuring the mean time to death or appearance of symptoms following viral inoculation . In this review we make a distinction between general virulence and neurovirulence . We define neurovirulence as the degree of pathogenesis in the nervous system, but intend it to be more encompassing than the simple ability of the virus to grow in the central nervous system (CNS) . This distinction is made possible by recent advances that permit an integrated assessment of the degree of pathology, reactive gliosis, and inflammatory response to infection in the intact organism with specific antisera and molecular probes. Gynecol Obstet Invest, 1995, 40(2), 97 - 100 Stable engraftment of human female genital mucous membrane xenografts on SCID mice; Kaufmann R et al.; We developed a model in which full-thickness human genital mucous membranes (fallopian tubes, endometrium) were heterotopically xenografted into the skin of severe combined immunodeficient (SCID) mice . The transplanted tissue retained its human phenotype for at least 4 weeks including the glandular epithelium, the lamina propria, and main parts of the grafted vessels . By using an occlusive chamber filled with covering phosphate-buffered saline we created a system that protected the moist human epithelial surface . This system will allow the study of the interaction of test substances, or of invasive, pathogenic microorganisms, with epithelial cells and other cellular components of the human genital mucosa under in vivo conditions. J Basic Microbiol, 1995, 35(5), 279 - 84 Studies of rifamycin production by Amycolatopsis mediterranei cells immobilized on glass wool; Abu-Shady MR et al.; Cells of Amycolatopsis mediterranei CBS 42575 were immobilized on glass wool for the production of rifamycins B and SV . Glass wool (CORNING type) of 8 microns in diameter has a better entrapment capacity for microbial cells of microorganism than the other types of glass wool used . The most suitable amount of glass wool was 0.8 g/50 ml . The best initial cell concentration used as inoculum was 40 mg cells/50 ml . Repeated batch production of rifamycins by immobilized cells on glass wool was carried out for 6 repeated batches . The results showed that reduction of batch time from 96 h to 48 h does not decrease rifamycin production by immobilized cells. G E N, 1995 Jan-Mar, 49(1), 23 - 8 Isolation and axenization of two entamoeba histolytica strains; Urdaneta H et al.; We describe the isolation and axenization of two E . histolytica strains, obtained from the stools of two patients with the clinical diagnosis of dysentery . We used Pavlova's medium for initial polixenic culture, and TYI-S-33 (Diamond's) medium for monoxenic and axenic cultures . In order to eliminate the microorganism contaminating the stools the following antibiotics were used: penicillin, streptomycin, ampicillin, chloramphenicol, kanamycin, nistatin, ceftriaxone and amphoterycin B . Both strains grew in similar culture conditions with a yield of 2 x 10(6) microorganism per tube of 15 ml . Both strains belong to pathogenic zymodemes, and virulence was determined by the capacity for producing hepatic abscesses in 100% of the hamsters inoculated intrahepatically. Int J Clin Lab Res, 1995, 25(3), 128 - 34 Cytokines in the acquired immunodeficiency syndrome and other infectious diseases; Poli G et al.; The pathogenesis of several infectious diseases is frequently related not only to their etiological agents of viral, bacterial, or parasitic nature, but also to the host immune response . Both inflammatory responses and specific immune responses to the invading microorganisms are controlled by complex networks of intercellular signalling molecules, namely cytokines . This rapidly growing family of mediators includes lymphokines, interleukins, and molecules such as tumor necrosis factors and interferons . Patterns of cytokine production from antigen- or allergen-specific T lymphocytic cell clones have been identified, firstly in animal models and subsequently in man, and are commonly referred to as TH0, TH1, and TH2 profiles . The predominance of one of these profiles strongly influences the type of immune response (humoral versus cellular) and, at least in some experimental models, whether the immune response is protective or harmful . This is most convincingly demonstrated in models of parasitic diseases, but has also been hypothesized to be involved in the pathogenesis of human immunodeficiency virus infection and the acquired immunodeficiency syndrome . Earlier studies on human immunodeficiency virus infection revealed that the replicative capacity of this retrovirus, like the herpes viruses, is strongly influenced by the cytokine milieu of infected cells . Transcriptional and post-transcriptional regulation of human immunodeficiency virus expression by human cytokines are examples of the complex interdigitation of viruses with the host immune system. Annu Rev Microbiol, 1995, 49, 777 - 805 Microbiology to 10,500 meters in the deep sea; Yayanos AA; Microorganisms in the deep sea live at high pressures, low and high temperatures, and in darkness . These parameters and their food supply govern their lives . The study of these creatures gives us an opportunity to see how life processes work at some of the highest temperatures and pressures of the biosphere . Cultured bacterial isolates can grow to over 100 MPa at 2 degrees C and to over 40 MPa at over 100 degrees C . These cultures comprise the foundation for the study of the molecular biology and biotechnology of these isolates . The PTk diagram shows how temperature and pressure affect the growth rate of a bacterium and helps in the search for relationships among bacteria from habitats differing in temperature and pressure. Annu Rev Microbiol, 1995, 49, 201 - 38 Polyketide synthase gene manipulation: a structure-function approach in engineering novel antibiotics; Hutchinson CR et al.; Polyketides are produced primarily in microorganisms through a specialized metabolism that is a variation of fatty acid biosynthesis . A strong sequence and mechanistic similarity among many of the fatty acid and polyketide synthase enzymes has led to two paradigms for explaining polyketide biochemistry . In one, polyketides are formed by enzyme complexes consisting of four to seven monofunctional proteins in which the beta-carbonyl groups of the intermediates resulting from the condensation of acetate residues are largely not reduced and cyclization of the intermediates typically produces aromatic compounds . The intermediates in the other model are formed by multifunctional enzymes in which each of the initial condensation products is processed through reduction; reduction and dehydration; or reduction, dehydration, and further reduction cycles to produce highly reduced compounds from acetate, propionate, and butyrate residues . Expression of the genes encoding each type of polyketide synthase, or their mutant forms, has provided much information about the underlying biochemistry and, in some cases, resulted in the formation of novel natural products. Perit Dial Int, 1995, 15(7 Suppl), S41 - 5; discussion S45-6 In vitro studies on the effect of dialysis solutions on peritoneal leukocytes; Jorres A et al.; Within the limitations of the various experimental protocols there appears to be agreement in the literature that unused dialysis fluids, at least when studied in vitro, adversely affect multiple leukocyte functions . The effects of dialysis fluids on leukocytes that have been reported to date include: 1 . Decreased cell viability of PMNs, PM phis, PBMCs, and lymphocytes; 2 . Inhibited phagocytosis and bacterial killing of various microorganisms by PM phis, PMNs, and peripheral blood leukocytes; 3 . Reduced secretion of leukotrienes (LTB4, LTC4) from peritoneal and peripheral blood PMNs and PBMCs; 4 . Reduced secretion of prostaglandins (PGE2, TXB2 and 6-keto-PGF1 alpha) from PM phi; 5 . Decreased production of many cytokines including TNF alpha, IL-8, and IL-6 in PM phis and PBMCs . In addition, several studies targeting the potential mechanisms by which dialysis solutions inhibit leukocyte function identified the initial low pH of the fluids in combination with their lactate content as being of primary relevance, since they may lead to a rapid intracellular acidification of leukocytes . Moreover, some studies indicated the importance of fluid hyperosmolarity and excessive glucose concentrations . These results are indirectly supported by recent in vitro investigations of alternative fluids, which showed improved leukocyte function following exposure to solutions with neutral pH, bicarbonate buffer instead of lactate, or normal osmolarity due to use of an alternative osmotic agent (e.g., glucose polymer) . In conclusion, the evidence obtained during in vitro experimentation suggests that current dialysis fluids are, indeed, not biocompatible . However, whether this also bears physiological relevance in vivo remains to be established in controlled clinical trials comparing conventional fluids to alternative solutions with improved biocompatibility . With regard to the future development of in vitro models for biocompatibility assessment, the following guidelines are suggested: 1 . Cell functional parameters should be studied in more than one cell population; 2 . Depending on which fluid aspect is under investigation, short or even very short exposure times should be used (e.g., < 30 min for pH/buffer studies; < 4 hours for osmolality/osmotic agent studies); 3 . In case the parameter/readout of interest requires longer study periods than indicated above (e.g., studies of cytokine induction or surface receptor expression), preincubation/recovery models should be preferred over coincubation experiments. Rocz Panstw Zakl Hig, 1995, 46(3), 279 - 92 {Abiotic and biotic transformation of persistent organochlorine compounds in the environment}; Strucinski P et al.; The presence of persistent organochlorine compounds in the environment is defined as being of anthropogenic origin . They are the result of intentional production (pesticides, solvents, dielectric and hydraulic fluids, flame retardants etc.) as well as they are produced as unintentional by-products from many processes (incineration, pulp and paper production, use and production of chlorinated aromatic chemicals and PVC) . Nowadays, they are recognized as one of the major classes of the contaminants in the environment because of their wide distribution and a high capacity to bioaccumulate in organisms--especially in higher levels of the trophic food chain . They have been also claimed to cause adverse effects on organisms and human . In the paper, the main classes of chlorinated hydrocarbons are presented, including pesticides, polychlorinated biphenyls and dioxins . The proposed degradative pathways--abiotic (photolysis, hydrolysis) as well as biotic (biotransformation by microorganisms and higher organisms, including human) are reviewed on the basis of current literature. Riv Eur Sci Med Farmacol, 1995 Jan-Feb, 17(1), 27 - 33 {Heat shock proteins in diabetes mellitus}; Parlapiano C et al.; The Heat Shock Proteins (HSP) are a special category of proteins synthesized from 2 types of cells, one originating from ordinary organs and the other highly specialized ones from mammals . Their synthesis originates from a reaction of the cells to heat shock and therefore it can be thought of as a defense mechanism activated by the cells to protect themselves from the damage done by heat . HSPs are also qualified as "molecular chaperons" since they are present at the assembling of other proteins and they protect them from any possible anomalous interactions even if they do not take an active part in the final making up of the protein itself . This chaperone role is the base of the hypothesis that HSPs could take part in the processing and presentation of the antigens . Two hypothesis have been formed on the role of HSPs in the immunological process . 1) HSP could be antigens that call for an immediate immunological reaction; 2) HSP could set off a self destructive mechanism brought on by an immunological reaction . From all this it emerges that the immunological reaction to HSP has two angles . One is protective in that it allows the cells to eliminate micro foreign-organisms and the other is harmful due to a badly regulated immunological reaction . In some studies it has been demonstrated that patients with varying autoimmunological disorders as LES and rheumatoid arthritis (AR), have autoantibodies against HSPs . Moreover the HSPs of certain microorganisms induce the formation of autoantibodies in the host and the proliferation of T cells in the synovial fluid in patients with AR.(ABSTRACT TRUNCATED AT 250 WORDS) Scand J Infect Dis, 1995, 27(3), 289 - 90 Actinobacillus actinomycetemcomitans pneumonia with chest wall and subphrenic abscess; Chen AC et al.; A 14-year-old girl had progressive dyspnea and right lower chest pain for about 1 1/2 months and a weight loss of 3 kg in 2 months . Chest X-ray revealed right pleural effusion and a round infiltration over the right lower chest, initially suspected to be malignant . Image study revealed consolidation in the right middle and lower lobes with abscess-like lesions around the right lower pleura and transdiaphrenic involvement to the subphrenic region . The lesion had also invaded the intercostal muscle . The pleural abscess was obtained by fiberoptic thoracoscopy, and culture of the pus grew typical colonies of Actinobacillus actinomycetemcomitans . After the causative microorganism had been identified, cefoxitin was given for 2 weeks followed by oral amoxicillin (250 mg/6 h) for a total period of 3 months . Follow-up chest X-ray revealed resolution of the lung lesions and the patient recovered gradually without any sequelae. Semin Thorac Cardiovasc Surg, 1995 Jan, 7(1), 47 - 53 The surgical treatment of patients with prosthetic valve endocarditis; David TE; Prosthetic valve endocarditis is associated with high mortality and morbidity . Although antibiotics alone may sterilize an infected prosthetic valve, adjunctive surgical therapy is often necessary . Depending on the virulence of the offending microorganism, the type of prosthetic valve and the site where it was implanted, the infection spreads into paravalvular structures, producing abscess . Systemic embolization of infected material may cause metastatic abscess . Thus, timing of surgery in these patients is crucial to optimize clinical results . An aggressive approach is justifiable in most patients with prosthetic valve endocarditis . It is believed that radical resection of all infected material and reconstruction of the heart and annuli with fresh autologous or glutaraldehyde-fixed bovine pericardium offer the best chance to eradicate the infection . Prolonged antibiotic therapy is also necessary in these patients . In the author's personal experience with 45 patients with prosthetic valve endocarditis, the infection was limited to the valve in 10 patients and had extended into the surrounding tissues in 35 . The operative mortality rate was 13% . The actuarial survival at 5 years was 61% +/- 5% . These results support the premise that radical resection of all infected materials offers a good chance for curing prosthetic valve endocarditis. Enferm Infecc Microbiol Clin, 1995 Jan, 13(1), 17 - 22 {Comparison of the automatized BacT/ALERT blood culture incubation and reading system and a conventional system}; Alonso C et al.; BACKGROUND: The aim of the present study was to compare the BacT/ALERT blood culture automatic management and reading system (Organon Teknika) with a conventional, nonautomatic technique (DUO, Bio-Merieux) . METHODS: 1,405 blood cultures were parallel compared . 263 of them were positive; out of these, 148 were considered as indicative of septicaemia, 38 of doubtful clinical significance and 77 as accidental contaminations . RESULTS: No differences were detected between both systems neither in the number of isolates obtained nor in the kind of microorganisms recovered or in the number of false-positive or false-negative readings . The conventional system detected 28% of significant isolates during the first 24 hours, reaching 77% after 48 hours; whereas the BacT/ALERT system had detected 57% of significant isolates after 12 hours, reaching 82% after 24 hours (p < 0.001) . CONCLUSIONS: The results obtained and the automatization of the BacT/ALERT system appoint it as a firm candidate to be included into the Clinical Microbiology laboratory routine. Int J Gynecol Pathol, 1995 Jan, 14(1), 70 - 4 IUD-associated pelvic actinomycosis: a report of five cases; Muller-Holzner E et al.; Five cases of intrauterine device (IUD)-associated tuboovarian actinomycosis are presented . The patients' ages ranged from 33 to 49 years and their IUD usage from 2 to 12 years . Clinical features of the cases included stenosis of the sigmoid colon in 4 cases, ureteric or bladder obstruction in two cases, and rectal fistula in a further instance . All patients were successfully treated postoperatively with penicillin or ampicillin . An initial diagnosis of ovarian carcinoma was considered in all cases . Although Actinomyces is difficult to differentiate histopathologically from microorganisms and other substances that cause the Splendore-Hoeppli phenomenon, morphological diagnosis permits a quicker and more practical approach than bacterial cultures in the establishment of postoperative antibiotic treatment . Intraoperative frozen-section diagnosis of an acute inflammatory process permits the surgeon to make an immediate decision in order to avoid extensive surgery when ovarian carcinoma is suspected. Rev Clin Esp, 1995 Jan, 195(1), 8 - 11 {Anticardiolipin antibodies in parenteral drug addicts: relationship with HIV}; Gonzalez Dominguez J et al.; The IgG isotype of anticardiolipin antibodies (aCL) and its possible relationship with the immunodeficiency virus (HIV) were studied in 65 parenteral drug addicts (PDA) . Thirty-seven patients were infected in the present study . Nineteen (51%) fulfilled diagnostic criteria of AIDS . Thirty-two of these 37 HIV-positive patients (86%) were IgG-aCL positive . Fourteen (50%) of the 28 HIV-negative patients were IgG-aCL positive . Our study reveals a lack of correlation between aCL and thrombocytopenia . None of the patients had thromboembolic complications . In AIDS patients no relationship was found between IgG-aCL levels and the presence of Pneumocystis carinii, other infections by opportunist microorganism, and clinical deterioration . Highly increased levels of IgG-aCL (> 80 GPL) were observed in three patients with AIDS and infectious endocarditis . In conclusion, given the non-specificity of aCL en PDA, it is our opinion that its measurement is of little help in daily clinical praxis. J Forensic Sci, 1995 Jan, 40(1), 45 - 54 Validation and population studies of the loci LDLR, GYPA, HBGG, D7S8, and Gc (PM loci), and HLA-DQ alpha using a multiplex amplification and typing procedure; Budowle B et al.; Studies were performed to evaluate the forensic applicability of multiplex amplification of the loci low density lipoprotein receptor, glycophorin A, hemoglobin G gammaglobin, D7S8, and group-specific component (PM loci) and simultaneous typing of these loci using a reverse dot blot approach where allele specific oligonucleotide probes are immobilized on a nylon membrane strip . These results were obtained by using the AmpliType PM PCR Amplification and Typing Kit . The experiments included: mixed body fluid studies; chemical contaminant effects on the DNA in body fluid samples; the effect of typing DNA from body fluid samples deposited on various substrates; the effect of microorganism contamination on typing DNA derived from blood and semen; the effect of sunlight and storage conditions on DNA typing; determination of the sensitivity of detection of the PM test kit; determination of cross-reactivity of DNA from species other than human; typing DNA derived from various tissues from an individual; and an evaluation of the hybridization temperature of the assay . The data demonstrate that DNA exposed to a variety of environmental insults yields reliable PM typing results . Allele and genotype frequencies for six loci (PM loci and HLA-DQ alpha) were determined in African Americans . Caucasians, southeastern Hispanics, and southwestern Hispanics . All loci meet Hardy-Weinberg expectations a