Appl Microbiol Biotechnol, 1990 May, 33(2), 139 - 44 A study of N- and P-dependence of nikkomycin production in continuous culture with immobilized cells; Truck HU et al.; The influence of nitrogen and phosphate on the biosynthesis of nikkomycin was studied in chemically defined medium . Cells of Streptomyces tendae were immobilized on porous glass particles in a fluidized-bed reactor for continuous production of nikkomycin . Phosphate had no significant influence on the biosynthesis of nikkomycin . However, even a very low concentration of phosphate in the production medium (0.0125 mmol/l) resulted in microbial growth on the particles . The concentration of nitrogen was highly effective in the regulation of the biosynthesis of nikkomycin . A high level of antibiotic production (maximum 3.05 mg/g dry cell weight per hour) was maintained for a period of about 200 h in a medium that contained nitrogen at a concentration of 0.2 g NH4NO3/l. Fortschr Med, 1990 Apr 20, 108(12), 232 - 4 {Occupational respiratory tract allergies}; Baur X; Numerous occupation-related substances of plant, animal, microbial and chemical origin are potent immunogens and allergens . In the Federal Republic of Germany, the most common form of occupational obstructive airways disease is baker's asthma, caused by the inhalation of flour dust and other related substances . Compliance with the industrial threshold limit values (TIL) at the workplace reduce the risk of contracting disease, but cannot exclude it completely . Apart from obtaining a detailed history, and performing a physical examination, the diagnostic work-up also requires inclusion of special allergy tests (prick, intradermal, RAST)--in equivocal cases also, after a prior exposure--free preparatory period, re-exposure and inhalative work-place-related provocative testing . Therapeutically, elimination of exposure heads the list of measures; in concrete terms, this can also mean a change of occupation or even occupational re-training. Ugeskr Laeger, 1990 Apr 9, 152(15), 1086 - 9 {Insuject-X for children . A clinical trial of the NPH insulin pen}; Rix M et al.; The use of Insuject-X for NPH insulin was tested by 21 children, age less than or equal to 10 years with insulin dependent diabetes mellitus less than or equal to 1 year, on conventional treatment with NPH insulin once or twice daily . After a preliminary period of one month the syringe injection regimen was changed to injections by Insuject-X for a four-month "pen" period . We observed no significant changes in metabolic control . The mean potency of NPH insulin in partly used cartridges was 103.6 +/- 5.6 IU/ml (range 91.0-118.1, n = 39) with no correlation to the residual volume or days of use . Measurements over 110 IU/ml were seen at the end of the study indicating the need of repeated instruction in use of the pen by children . No microbial contamination of the cartridges, nor any local reactions at injection sites were found . We observed more technical problems than in adult studies indicating that children handle the pen more roughly . The accept of Insuject-X was good as a more convenient means of injecting . All of the children preferred to continue using it. Biophys Chem, 1990 Apr, 35(2-3), 271 - 85 Physiochemical characterization of substituted chromeno{4,3-b}{1,5}benzodiazepine stereoisomers designed as cell membrane active antitumor agents; Werner W et al.; As an alternative to naturally occurring pyrrolo{2,1-c}{1,4}benzodiazepines (e.g., antramycin) which possess properties of DNA alkylation, we have designed several antileukemic chromeno{4,3-b}{1,5}benzodiazepine derivatives with potential activity toward leukemia cell membranes and the cyclic nucleotide system . The cis and trans diastereoisomers were characterized by NMR . The absolute configurations of the enantiomers were established by X-ray diffraction and circular dichroism (CD) measurements . By means of absorption spectroscopy and determinations of fluorescence and fluorescence decay, it was found that the cancerostatically active compound (+)(6aR, 13aS)-3,4-dimethoxy-10,11-dimethyl-6,6a,7,8,13, 13a-hexahydrochromeno{4,3-b}{1,5}benzodiazepine (ZIMET 54/79) and its biologically inactive (-) enantiomer (ZIMET 55/79) interact with liposomal membranes . At pH values of 6.0 and 7.3 the long-wave absorption bands of these agents showed weak bathochromic and hypochromic effects upon addition of neutral, and positively and negatively charged phosphatidylcholine and phosphatidylcholine/cholesterol liposomes . Such spectral changes are interpreted as resulting from the binding of both agents to phospholipid bilayers . Steady-state determinations using the membrane probe 1-anilino-8-naphthalenesulfonic acid (1,8-ANS) led to the observation of a small decrease in fluorescence intensity in the presence of either agent . Time-resolved measurements demonstrate that the mechanism of action of the agents occurs mainly through the partial displacement of probe molecules from regions of hydrophobic binding to areas of greater solvent accessibility . No significant differences in binding between the cancerostatically active and inactive enantiomers with liposomes (archiral systems) were detectable on the basis of spectrophotometric and fluorescence determinations . Cell membrane bound adenylate cyclase is stimulated by ZIMET 54/79, resulting in an increase of 103% in the level of cAMP in mouse L1210 leukemia cells . On examination of structure-activity relationships, it was found that the biological activity (leukemia L1210, P388, Lewis lung carcinoma, melanoma B16, increase in cAMP) is correlated with the particular configuration (6aR,13aS) and type of substituent at positions 3 and 4 of the benzo ring in the case of alkoxy groups and positions 10 and 11 for methyl groups . No activity was detected toward DNA/RNA using microbial test systems. Helv Chir Acta, 1990 Apr, 56(6), 947 - 50 {Simple references of the differential blood picture in assessing the immune status of immunologically compromised severely injured patients}; Holch M et al.; Infectious complications threaten the survival of severe traumatized patients in the intensive care unit . Major cause is a secondary immunodeficiency syndrome as a consequence of overloading the immune system by tissue debris and microbial antigens . Antigen presenting cells of the monocyte-macrophage line become activated unspecifically and produce immunosuppressive monokines, which modulate the T- and B-cell systems and weaken the specific immune response to antigens . In 150 severe injured patients (mean ISS 31; 15 patients died due to infections) we found that a decrease of lymphocytes below 1000/microliters and an increase of monocytes up to more than 1000/microliters within the first 24 hours correlate with developing infection in such a manner, that the lymphocyte/monocyte-quotient on day 1 was 2.0 in survivors and 0.9 in subjects, who died due to infections. J Econ Entomol, 1990 Apr, 83(2), 374 - 6 Confirmation of the safety of Lagenidium giganteum (Oomycetes: Lagenidiales) to mammals; Kerwin JL et al.; Lagenidium giganteum Couch, a fungal parasite of mosquito larvae, is considered a promising agent for operational control . Quantitative reisolation of the fungus from rodent blood and tissue is easily accomplished because the cell walls are much more persistent than those of mammalian cells . The mycelium forms discrete, septate cells very early in its development, in marked contrast to filamentous fungi . The fungus is rapidly cleared from mice following intraperitoneal injection of large quantities of mycelium and oospores . More than 95% of viable cells are cleared within 24 h . Mortality following intravenous injection of mycelium in tail veins of mice is caused solely by embolism of heart and lung tissue . Recently revised U.S . Environmental Protection Agency protocols for testing of microbial pest control agents may have to be altered further to accommodate physically large microbial agents such as L . giganteum. Appl Environ Microbiol, 1990 Apr, 56(4), 1012 - 6 Microbial degradation of trichloroethylene in the rhizosphere: potential application to biological remediation of waste sites; Walton BT et al.; The possibility that vegetation may be used to actively promote microbial restoration of chemically contaminated soils was tested by using rhizosphere and nonvegetated soils collected from a trichloroethylene (TCE)-contaminated field site . Biomass determinations, disappearance of TCE from the headspace of spiked soil slurries, and mineralization of {14C}TCE to 14CO2 all showed that microbial activity is greater in rhizosphere soils and that TCE degradation occurs faster in the rhizosphere than in the edaphosphere . Thus, vegetation may be an important variable in the biological restoration of surface and near-surface soils. Cornea, 1990 Apr, 9(2), 122 - 4 Acridine orange and Gram stains in infectious keratitis; Groden LR et al.; Two hundred thirty consecutive cases of presumed infectious keratitis were reviewed . Cultures were positive in 49.5% (114 of 230) . Acridine orange stain sensitivity (81%) was significantly greater than gram stain sensitivity (65%) (p less than 0.002) . Gram stain specificity was 92%, and acridine orange specificity was 89% . In keratitis with low or moderate growth, acridine orange was positive in 73% (61 of 84) as compared with Gram stain 53% (45 of 84), (p less than 0.001) . In cases of heavy microbial growth, Gram stain was positive in 97% (29 of 30), acridine orange in 100% (30 of 30) . This study demonstrates that both Gram stain and acridine orange stain are excellent in cases of infectious keratitis with heavy microbial growth, but that acridine orange is significantly better than Gram stain in cases with low amounts of organisms. Oral Surg Oral Med Oral Pathol, 1990 Apr, 69(4), 437 - 43 An animal model for mucositis induced by cancer chemotherapy; Sonis ST et al.; Mucositis induced by chemotherapy is a painful and often dose-limiting side effect of cancer therapy . Furthermore, loss of the integrity of the oral epithelium often provides a microbial portal of entry and leads to sepsis . The present study describes the first animal model for chemotherapy-induced mucositis . The combination of three intraperitoneal injections of 5-fluorouracil at 5-day intervals and superficial mechanical mucosal irritation resulted in clinical breakdown of the oral mucosa characterized by ulcerative mucositis in Golden Syrian hamsters . Both clinical and histologic evaluation demonstrated that these changes were similar to those described in human beings and followed a pattern influenced by the degree of myelosuppression . This model should be of significance in establishing the stomatotoxicity of new chemotherapeutic agents, in evaluating medicaments to treat mucositis, and in studying the influence of oral mucosal breakdown on sepsis in myelosuppressed persons. J Immunol, 1990 Apr 1, 144(7), 2745 - 50 Requirement of lipophosphoglycan for intracellular survival of Leishmania donovani within human monocytes; McNeely TB et al.; The function of the lipophosphoglycan of Leishmania donovani parasites was investigated in human peripheral monocytes . In contrast to wild-type L . donovani which grow in monocytes, incubation of monocytes with two variant lines of L . donovani, defective in lipophosphoglycan expression, resulted in the entry of the variant cells into the monocytes and their subsequent destruction . Passive transfer of lipophosphoglycan to the variant cells led to prolonged survival in monocytes . These results indicate that lipophosphoglycan is required by the parasite for intracellular survival . To investigate one possible protective role of the glycoconjugate, preincubation of monocytes with a suspension of lipophosphoglycan and subsequent treatment of the cells with PMA or opsonized zymosan resulted in an attenuation of the oxidative burst; the attenuation effect was concentration dependent on the glycoconjugate and independent of preincubation time . Moreover, hydrophobic beads, coated with lipophosphoglycan, were phagocytized by monocytes and found to inhibit oxygen consumption in monocytes activated with PMA . These results suggest a possible relationship between the absence of lipophosphoglycan in the variant parasites and their inability to survive within monocytes . Although the precise molecular basis remains to be elucidated, the ability of lipophosphoglycan to impair the microbial oxidative response may be a contributing factor in its requirement for intracellular survival. Scand J Work Environ Health, 1990 Apr, 16(2), 85 - 95 Biosafety considerations in industries with production methods based on the use of recombinant deoxyribonucleic acid; Andrup L et al.; Since no occupational accidents or diseases have been attributed specifically to the use of constructions containing recombinant deoxyribonucleic acid (rDNA), this paper evaluates the occupational health risks in industries utilizing genetically manipulated organisms mainly on the basis of theoretical considerations . Bacteria, filamentous fungi, yeasts, and mammalian cells in culture are in use . For each of these systems the possible hazards are considered . Concerning microbial production systems, infections are regarded as the main problem, but the risk of infection is considered extremely low . As for cells in culture, only dormant viruses are regarded as problematic, but well-defined production cell lines should not contain such undetected and dangerous viruses . Overall, the additional risks posed by rDNA-modified micro-organisms are minor . Only long-term observations can, however, confirm this assumption, and consequently the highest feasible containment measures should still be used in the years to come. FASEB J, 1990 Apr 1, 4(6), 1591 - 7 Bifunctional thymidylate synthase-dihydrofolate reductase in protozoa; Ivanetich KM et al.; Protozoa contain thymidylate synthase (TS) and dihydrofolate reductase (DHFR) on the same polypeptide . In the bifunctional protein, the DHFR domain is on the amino terminus, TS is on the carboxyl terminus, and the two domains are separated by a junction peptide of varying size depending on the source . The native protein is composed of a dimer of two such subunits and is 110-140 kDa . Most studies of the bifunctional TS-DHFR have been performed with the protein from anti-folate resistant strains of Leishmania major, which show amplification of the TS-DHFR gene and overproduction of the bifunctional protein . The Leishmania TS-DHFR has also been highly expressed in heterologous systems . There appears to be extensive communication among domains and channeling of the H2folate product of TS to DHFR . Anti-folates commonly used to treat microbial infections are poor inhibitors of L . major DHFR . However, selective inhibition of L . major vs . human DHFR does not appear difficult to achieve, and selective inhibitors are known . The TS-DHFR from Plasmodium falciparum has also been cloned and has recently been expressed in Escherichia coli, albeit in small amounts . Interestingly, pyrimethamine-resistant strains of P . falciparum all have a common point mutation in the DHFR coding sequence (Thr/Ser 108 to Asn), which causes decreased binding of the folate analog . It is suggested that if an appropriate inhibitor of the pyrimethamine-resistant P . falciparum DHFRs can be found, it may serve in combination with pyrimethamine as an antimalarial regimen with low propensity for the development of resistance . In the future, we project that we will have a detailed knowledge of the structure and function of TS-DHFRs, and have the essential tools necessary for a molecular-based approach to drug design. Exp Parasitol, 1990 Apr, 70(3), 367 - 71 Thymidylate synthase-dihydrofolate reductase in protozoa; Ivanetich KM et al.; In protozoa, thymidylate synthase (TS) and dihydrofolate reductase (DHFR) exist on the same polypeptide . The DHFR domain is on the amino terminus, TS is on the carboxy terminus, and the domains are separated by a junction peptide of varying size depending on the source . The native protein is a dimer of two such subunits and is 110-140 kDa . Most studies of bifunctional TS-DHFR have been performed with the protein from anti-folate resistant strains of Leishmania major, which show amplification of the TS-DHFR gene and overproduction of the bifunctional protein . The Leishmania TS-DHFR has also been highly expressed in heterologous systems . There is extensive communication between domains, and channeling of the H2folate product of TS to DHFR . Anti-folates commonly used to treat microbial infections are poor inhibitors of L . major DHFR . However, selective inhibitors of L . major vs human DHFR have been found . The TS-DHFR from Plasmodium falciparum has also been cloned and sequenced . Interestingly, pyrimethamine-resistant strains of P . falciparum have a common point mutation in the DHFR coding sequence which causes decreased binding of the folate analog . A detailed knowledge of the structure and function of protozoan TS-DHFRs will soon be available. J Dairy Sci, 1990 Apr, 73(4), 985 - 94 Interaction between the respiratory burst activity of neutrophil leukocytes and experimentally induced Escherichia coli mastitis in cows; Heyneman R et al.; The respiratory burst activity of neutrophil leukocytes from bovine peripheral blood was studied before and during an experimentally induced Escherichia coli mastitis . The competence of neutrophils to generate reactive oxygen species following stimulation with opsonized particles prior to infection was negatively correlated with severity of subsequently induced E . coli mastitis . In the presence of the soluble activator, phorbol myristate acetate, no such correlation was obtained . However, combination of blood neutrophil numbers with phorbol myristate acetate induced respiratory burst competence, called reactive oxygen species-generating capacity, displayed a negative correlation with the intensity of a subsequent inflammation of the bovine mammary gland . At the onset of mastitis, a concomitant reduction in blood neutrophil numbers, a strong shift in cell types, and a substantial decrease in production of reactive oxygen species occurred . Reestablishment and even enhancement of the respiratory burst activity coincided with the reappearance of mature neutrophils . Possible stimulatory effects on neutrophil superoxide generation are discussed . Data suggest that generation of reactive oxygen species by mature neutrophils may be of primary importance for microbial killing during the onset and recovery from mastitis. Trends Biochem Sci, 1990 Apr, 15(4), 158 - 62 Comparison of active sites of some microbial ribonucleases: structural basis for guanylic specificity; Sevcik J et al.; Crystallographic studies of enzymes complexed with suitable ligands are an important tool to aid our understanding of biological catalysis . To this goal, a contribution is made by analysing structures of complexes formed by three guanyl-specific ribonucleases with guanosine 3'-monophosphate. J Antibiot (Tokyo), 1990 Apr, 43(4), 397 - 402 Method of search for microbial inhibitors of mevalonate biosynthesis using animal cells; Kumagai H et al.; A new screening method for specific inhibitors of mevalonate biosynthesis was established using Vero cells, an animal cell line . The cultures selected were those which inhibited the growth of Vero cells in the EAGLE's minimum essential medium supplemented with 2% calf serum (2% CS-MEM) but lacked inhibitory activity against the growth of cells in 2% CS-MEM supplemented with 1 mM mevalonate . By this screening method, inhibitors of the two enzymes involved in mevalonate biosynthesis, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase and HMG-CoA reductase, were selected from about 11,000 soil isolates . The beta-lactone 1233A, a fungal metabolite, was found to be the first naturally occurring compound which inhibits HMG-CoA synthase specifically and strongly . Monacolins K and J, inhibitors of HMG-CoA reductase, were also detected and identified. J Biotechnol, 1990 Apr, 14(1), 99 - 114 Monitoring of enzymes during chromatographic separations; Stamm WW et al.; An on-line enzyme assay is presented based on flow injection techniques combined with fluorimetric detection . It allows to monitor NAD-dependent oxidoreductases during the purification of microbial crude extracts or partially purified enzymes by fast protein liquid chromatography (FPLC) in a near real-time mode . The arrangement is simple and can be easily integrated in the chromatographic system avoiding dead volumes . A high measuring frequency (up to 180 samples h-1) and a short response time (10-30 s) are achieved . The method has a low limit of detection (approximately 0.01 U ml-1), and a good reproducibility (1-4%), the injected sample volume is only 2 microliters. J Biotechnol, 1990 Apr, 14(1), 63 - 70 Prerequisites for the on-line control of microbial processes by flow injection analysis; Ogbomo I et al.; Problems associated with the use of biosensors in process control, e.g . difficulties of sterilization and sensor fouling, are shortly displayed, and possibilities to overcome them are outlined . The advantages of flow injection analysis (FIA) are demonstrated and examples for efficient sampling systems connected with this method are reviewed . Special emphasis is given to problem-orientated sample pretreatments, preventing fast inactivation of immobilized enzymes in the analysis system . Examples of problem-orientated sample pretreatment units are given . A proposal for a computer-controlled self-calibrating FIA system is given. Nature, 1990 Mar 29, 344(6265), 395 - 400 Signal transduction in bacteria; Stock JB et al.; Cells display a remarkable ability to respond to small fluctuations in their surroundings . In simple microbial systems, information from sensory receptors feeds into a circuitry of regulatory proteins that transfer high energy phosphoryl groups from histidine to aspartate side chains . This phosphotransfer network couples environmental signals to an array of response elements that control cell motility and regulate gene expression. Vestn Otorinolaringol, 1990 Mar-Apr, (2), 52 - 6 {The cause-effect interdependence in the pathogenesis of chronic tonsillitis as an infectious allergic process}; Iakovenko VD et al.; Clinical and immunological examinations of 360 patients with chronic tonsillitis and 286 patients suffering from systemic complications of chronic tonsillitis at various post-tonsillectomy stages demonstrated that the major immunopathological factor in the case of chronic compensated tonsillitis was microbial allergy and in the case of chronic decompensated tonsillitis, autoimmune disorders . The high titer of autoantibodies to tonsillar antigen that persisted at various post-tonsillectomy stages made it necessary to use systemic immune correction as part of therapy of chronic tonsillitis. J Appl Bacteriol, 1990 Mar, 68(3), 279 - 83 Investigations of the effectiveness of detergent washing, drying and chemical disinfection on contamination of cleaning cloths; Scott E et al.; Detergent washing, drying and chemical disinfection for decontamination of cleaning cloths was investigated with cloths contaminated by use in the domestic environment . Detergent washing produced only limited reductions in microbial contamination and cloths then stored at room temperature for 24 h showed increases in contamination due to multiplication of residual survivors . For effective and consistent decontamination of cloths, detergent washing followed by drying at 80 degrees C for 2 h was required . Hypochlorite and phenolic disinfectants produced significant reductions in contamination, but chemical disinfection may be unreliable where cloths are heavily contaminated. Br J Ophthalmol, 1990 Mar, 74(3), 133 - 5 Contamination of contact lens storage cases by Acanthamoeba and bacteria; Larkin DF et al.; In order to identify possible risk factors for microbial keratitis the storage cases for contact lenses of 102 asymptomatic lens wearers were tested for contamination by bacteria and free-living amoebae . Of this group 43 had significant counts of viable bacteria and only 40 had negligible counts . Seven had contamination by acanthamoebae, of whom six also had significant bacterial counts . These results were categorised according to the type of contact lens worn and the lens disinfection method . The high rates of contamination by apathogenic and pathogenic organisms, in particular Acanthamoeba, and the probable support by contaminating bacteria of Acanthamoeba, are discussed. Appl Environ Microbiol, 1990 Mar, 56(3), 590 - 4 Detection of ruminal bacteria that degrade toxic dihydroxypyridine compounds produced from mimosine; Allison MJ et al.; Leucaena leucocephala, a tropical leguminous shrub, contains a toxic amino acid, mimosine . Successful utilization of leucaena as a ruminant forage depends on colonization of the rumen by bacteria that degrade dihydroxypyridines (DHP), which are toxic intermediates in the metabolism of mimosine . Populations in the rumina of animals in some parts of the world, however, do not include bacteria that are able to carry out this degradation . We thus describe tests for the presence of DHP degraders in ruminal populations that are based on degradation (loss) of DHP compounds from culture media . Results obtained with the tests indicate that DHP degraders were not part of microbial populations in the rumina of cattle, sheep, and goats in Iowa, while most rumen samples examined from animals from the Virgin Islands and Haiti contained DHP degraders . These results confirm and extend the findings of others about geographic limits to the distribution of these important ruminal bacteria. Infect Control Hosp Epidemiol, 1990 Mar, 11(3), 139 - 43 Alcohol for surgical scrubbing? Larson EL, Butz AM, Gullette DL, Laughon BA. To test the effects of four surgical scrub products on colonizing hand flora, 60 healthy adult volunteers were assigned by block randomization (12 subjects per group) to use one of the following formulations: 70% ethyl alcohol with 0.5% chlorhexidine gluconate (ALC); a liquid detergent base containing 1% triclosan (TRI); a liquid detergent base containing 4% chlorhexidine gluconate (CHG); a liquid detergent base containing 7.5% povidone-iodine (PI); or a nonantimicrobial liquid soap (control) . Using standard protocol, subjects performed a surgical scrub daily for five consecutive days . Hand cultures were obtained at baseline and on test days 1 and 5 immediately after the scrub and following four hours of gloving . After the first and last scrubs, ALC, CHG and PI resulted in significant reductions in colonizing flora when compared to the control . Additionally, by day 5 ALC was associated with an almost 3-log reduction as compared to an approximate 1.5-log reduction for CHG and PI and less than a 1-log reduction of TRI and the control (p = .009) . After four hours of gloving on both days 1 and 5, microbial counts on hands of subjects using ALC, TRI and CHG were significantly lower than counts for the control (p less than .001), whereas there was no significant difference in counts between the PI and control groups (p = .41) . Skin assessment by study subjects rated products from least to most harsh as follows: control, TRI, CHG, ALC and PI p = .00001) . It was concluded that ALC could be an efficacious and acceptable alternative for surgical scrubbing. Am J Orthod Dentofacial Orthop, 1990 Mar, 97(3), 213 - 8 Effects of orthodontic bands on microbiologic and clinical parameters; Huser MC et al.; The aim of this study was to evaluate the effect of placement of orthodontic bands on the gingival tissues and the microbial composition of dental plaque . Ten subjects undergoing orthodontic treatment completed the study . In each subject four sites were examined: two test sites with orthodontic bands and two control sites free of bands . Clinical and bacterial examinations were performed before the beginning of the treatment and 5, 7, 47, 72, and 90 days after placement of the orthodontic appliances . Plaque index (Pl I) and bleeding scores increased significantly on banded teeth as compared with control sites . Probing depth remained within normal values for both test and control groups . The composition of dental plaque determined by dark-field microscopy showed significant shifts in the test sites after banding . Changes consisted of an increase in the percentage of spirochetes, motile rods, filaments, and fusiforms; conversely, a decrease in cocci was noted . During the same period no significant changes in the bacterial distribution were observed in the control group. Antibiot Khimioter, 1990 Mar, 35(3), 3 - 6 {Study of the conditions for reproducing the processes of antibiotic biosynthesis . Determining the limiting stage of the process of mass transfer of oxygen}; Kuz'mina LM et al.; A theoretical method for estimating limiting stage of oxygen mass transfer is proposed . The method is based on calculation and comparison of particular resistance of separate stages of mass transfer: mass transfer through the gas-liquid boundary, oxygen transport in the liquid phase, mass transfer through the liquid-cell boundary and oxygen consumption by microbial cells . With the proposed method, particular resistance was calculated and conditions for oxygen mass transfer were analyzed in the biosynthesis of sisomicin as an example . As a result the conditions for reproducibility of the process in apparatus of various size were determined. World J Surg, 1990 Mar-Apr, 14(2), 227 - 30 Nonoperative antiinfective treatment of intraabdominal infections; Pollock AV; There are many causes of peritonitis . Primary peritonitis is rare, but may complicate cirrhosis of the liver or may, in developing countries, be caused by Mycobacterium tuberculosis . It is occasionally iatrogenic, particularly as a complication of continuous ambulatory peritoneal dialysis . It is, however, most frequently the result of perforation of a hollow viscus, caused by either trauma or disease . Its most lethal form follows breakdown of an intestinal anastomosis . Primary and iatrogenic peritonitis should be treated with antibiotics, and localized abscesses can sometimes be cured by percutaneous aspiration . Secondary peritonitis requires resuscitation, antibiotics, and operation . When there is gross microbial invasion, it is wise to avoid suture of the hollow viscus . If there is a strong chance of recurrence of intraabdominal abscesses, nonclosure of the abdomen is theoretically desirable and allows frequent reexploration . This is particularly applicable to pancreatic abscesses. Microbiol Rev, 1990 Mar, 54(1), 75 - 87 Influence of interfaces on microbial activity; van Loosdrecht MC et al.; Bacterial adhesion in natural and artificial systems has been critically reviewed to investigate the influences exerted by the presence of interfaces . Numerous investigations have demonstrated that, in the presence of a solid phase, the activity of bacterial cultures is changed . Reviewing relevant literature, two problems were encountered . One is of an experimental nature . Due to lack of similarity in experimental conditions, disparate experiments often cannot be compared; their results may even appear conflicting . The other problem is of an interpretational nature: several hypothetical theories exist which try to explain the effect of surfaces on microbial activity . These theories often confuse changes in the medium and limitations in mass transfer which are due to the presence of solid surfaces (indirect influences) with changes in cell properties (direct influences) . Whenever a surface is reported to influence the metabolism of bacteria, the action is found almost exclusively to be due to changes in the medium or environment and is therefore indirect . Based on data reported in the literature, and by using thermodynamic and kinetic considerations, it is concluded that so far neither experimental nor theoretical evidence exists for a direct influence of interfaces on microbial activity. J Anim Sci, 1990 Mar, 68(3), 863 - 9 New food safety initiatives in the Food Safety and Inspection Service, U.S . Department of Agriculture; Norcross MA et al.; The production of meat and poultry products has become increasingly complex . Technological growth has contributed to the need for sophistication in determining the origin and risk of food-borne microbial infections as well as environmental contaminants . The increasing use of agricultural chemicals in animal production and to some extent in processed foods has led to the presence of chemical residues in meat and poultry . These changes have caused the Food Safety and Inspection Service (FSIS), a public health agency within the United States Department of Agriculture (USDA), to institute new food safety initiatives and procedures for inspection of meat and poultry products . The goal is to reduce risks to the public health from conditions observed during antemortem and postmortem inspection or detected during processing . FSIS is committed to scientific innovation and has implemented several rapid inplant tests that have given the Agency inexpensive, less disruptive methods to determine product adulteration contamination. Am J Gastroenterol, 1990 Mar, 85(3), 231 - 7 Bacterial overgrowth; Kirsch M; Small bowel bacterial overgrowth is a syndrome manifested by malabsorption, weight loss, and diarrhea . Human intestinal flora is part of a complex ecosystem regulated by host mechanisms, environmental factors, and bacterial interactions . Numerous conditions can tilt this balance to favor bacterial contamination of the gut . Knowledge of intestinal microbial control enables the clinician to better understand the pathophysiology and the clinical features of this disorder . Current strategies in diagnosis and therapy are discussed. Arch Tierernahr, 1990 Mar, 40(3), 245 - 57 Studies on the evaluation of feed protein for ruminants . 1 . Passage of nitrogen fractions to the duodenum of dairy cows fed different protein and carbohydrate sources; Voigt J et al.; The duodenal passages of non-ammonia nitrogen (NAN), amino acid N (AA-N) and microbial N (MN) were measured in seven duodenal fistulated dairy cows (6130 kg FCM/305 d) during lactation receiving 30 different rations similar to those used in dairy practice . The rations consisted of roughage (protein-rich silages, hay) and concentrate mixture (corn, barley, oat) in a ratio of 60:40 on a DM basis or roughage/concentrate mixture/fodder beets in the proportions 60:20:20 or 60:0:40 respectively . N supplements consisted of soya bean meal and peas meal (untreated or treated with formaldehyde in each case), rapeseed meal, fish meal and urea . DM intake varied between 9.6 and 19.1 kg/d, the crude fibre content between 166 and 270 g/kg DM, the crude protein (CP) content between 111 and 184 g/kg DM, the AA content (N basis) of the CP between 51 and 82%, the unfermentable CP content of the CP between 23 and 49% and the organic matter digestibility between 70 and 79% . The duodenal passage of NAN was 24.2 +/- 2.7 g/kg DM intake, 34.9 +/- 4.1 g/kg apparently digestible organic matter (in total tract, DOM), 43.3 +/- 5.5 g/kg apparently digestible carbohydrates or 4.2 +/- 0.5 g/MJ net energy fat, (y +/- s, n = 90) . The value measured for AA-N was 16.8 +/- 2.9 g/kg DM intake, and that for RNA-labelled microbial CP was 146 +/- 26 g/kg DOM . NAN passage (g/kg DM intake) correlated more closely with the duodenal digesta flow rate (DFR) (kg digesta/kg DM intake) as an intrinsic animal factor (r = 0.78) and with the rumen content dilution rate (RDR) (passage of microbial-free organic matter at duodenum/kg BW0.75.h) as a ration dependent factor (r = 0.64) than with the UDP fraction (% of ration CP) (r = 0.50) or other ration parameters . It was concluded that the specific effect of protein concentrates in mixed rations on duodenal NAN yields in lactating dairy cows is lower than hitherto assumed . The duodenal NAN yield of a single feedstuff or ration (g/kg DM) in cows is dependent on animal and feeding factors . The DFR could represents a suitable target for breeding activities. AIDS Res Hum Retroviruses, 1990 Mar, 6(3), 393 - 9 Muramyl dipeptide inhibits replication of human immunodeficiency virus in vitro; Masihi KN et al.; In the search for compounds capable of inducing endogenous production of colony-stimulating factor (CSF) and possessing activity against human immunodeficiency virus (HIV), an immunomodulator, muramyl dipeptide (MDP), was investigated . MDP can enhance monocyte-macrophage CSF in serum and promote nonspecific resistance against a variety of microbial pathogens . MDP exhibited an inhibitory activity against HIV infection of CD4+ H9 lymphocytes and U937 monocytoid cells . An inhibitor of viral reverse transcriptase, 2', 3'-dideoxyadenosine, produced potent inhibition in cultures which were similarly infected with HIV . MDP could partially reduce antigen production in persistently HIV-infected KE37/1 lymphocyte cultures. In Vitro Cell Dev Biol, 1990 Mar, 26(3 Pt 1), 275 - 9 Fish cell lines: establishment and characterization of three new cell lines from grass carp (Ctenopharyngodon idella); Lu YA et al.; Three new cell lines were established from tissues of the grass carp, Ctenopharyngodon idella . Derived from the fin, snout, and swim bladder of two apparently healthy diploid fry, these cell lines have been designated GCF, GCS-2, and GCSB, respectively . The cells grew at temperatures between 24 degrees and 36 degrees C with optimal growth at 32 degrees C and have been subcultured more than 50 times since their initiation in August 1986 . Two of the lines remained diploid or pseudodiploid after 38 passages . The cells were tested for microbial contamination, and plating efficiencies were determined . The three cell lines were sensitive to Rhabdovirus carpio (RVC), infectious hematopoietic necrosis virus (IHNV), golden shiner virus (GSV), chum salmon virus (CSV), and infectious pancreatic necrosis virus serotype VR299 IPNV) . They were refractory to channel catfish virus (CCV), channel catfish reovirus (CRV), chinook salmon paramyxovirus (CSP), and an Ab serotype of IPNV. J Bacteriol, 1990 Mar, 172(3), 1180 - 5 Microbial growth patterns described by fractal geometry; Obert M et al.; Fractal geometry has made important contributions to understanding the growth of inorganic systems in such processes as aggregation, cluster formation, and dendritic growth . In biology, fractal geometry was previously applied to describe, for instance, the branching system in the lung airways and the backbone structure of proteins as well as their surface irregularity . This investigation applies the fractal concept to the growth patterns of two microbial species, Streptomyces griseus and Ashbya gossypii . It is a first example showing fractal aggregates in biological systems, with a cell as the smallest aggregating unit and the colony as an aggregate . We find that the global structure of sufficiently branched mycelia can be described by a fractal dimension, D, which increases during growth up to 1.5 . D is therefore a new growth parameter . Two different box-counting methods (one applied to the whole mass of the mycelium and the other applied to the surface of the system) enable us to evaluate fractal dimensions for the aggregates in this analysis in the region of D = 1.3 to 2 . Comparison of both box-counting methods shows that the mycelial structure changes during growth from a mass fractal to a surface fractal. Trends Pharmacol Sci, 1990 Mar, 11(3), 122 - 6 Somnogenic activity of immune response modifiers; Krueger JM; Sleepiness is a presenting symptom in nearly all infectious diseases . James Krueger describes how microbial products, such as muramyl peptides, lipid A and double-stranded RNA, as well as endogenous products elicited by these substances, such as interleukin 1, modulate sleep . The altered sleep during infection seems to result from an exaggerated activation of physiological sleep mechanisms, since normal sleep is controlled by a wide range of substances including many of these immune response modifiers. Infection, 1990 Mar-Apr, 18(2), 86 - 90 Efficacy of intravenous immunoglobulins in patients with advanced HIV-1 infection . A randomized clinical study; Brunkhorst U et al.; 40 adults with symptomatic HIV-1 infection (AIDS related complex {ARC} WR 2B-4B or AIDS WR 5-6) were randomized into two groups, receiving either 200 mg of an i.v . immunoglobulin preparation (ivIg)/kg body weight every other week or no such treatment . Medical care and antibiotic therapy were comparable in the two groups . Frequency of opportunistic infections, "B"-symptoms, number of T-helper cells, change of disease stage (Walter Reed Classification, WR), delayed cutaneous hypersensitivity, onset and clinical course of Kaposi's sarcoma, neurological manifestations and proportion of patients alive at the end of the observation period were evaluated . After an average observation period of 13.8 months, decreased mortality was observed in ivIg treated patients of WR 5-6 (p less than 0.004) . Frequency and microbial spectrum of opportunistic infections, the most frequent cause of death, were not influenced significantly by ivIg treatment . No statistically relevant differences concerning the other parameters were observed . A similar beneficial effect of ivIg in WR 2B-4 patients has not become apparent so far. J Exp Med, 1990 Mar 1, 171(3), 819 - 29 Human anti-p68 autoantibodies recognize a common epitope of U1 RNA containing small nuclear ribonucleoprotein and influenza B virus; Guldner HH et al.; Autoantibodies from patients with systemic rheumatic diseases were used to map antigenic sites on the 68-kD autoantigen (p68) associated with (U1)RNA-containing small nuclear ribonucleoprotein (snRNP) particles . With truncated recombinant fusion proteins and synthetic peptides, a subset of anti-p68 autoantibodies was found to recognize the amino acid sequence motif Glu-Arg-Lys-Arg-Arg (ERKRR) . To investigate the possible involvement of epitopes shared by microbial antigens and host self-components in initiation of autoimmunity (molecular mimicry), a sequence data bank was screened for proteins containing an amino acid motif identical or related to ERKRR . The identical motif was found on the M1 matrix protein of influenza B viruses, and affinity-purified human anti-ERKRR autoantibodies recognized this epitope also in the viral amino acid sequence context . The common epitope recognized by human autoantibodies suggests that influenza B virus infection may play a role in initiation of the anti-p68 and anti-(U1)RNP autoimmune response. Anal Biochem, 1990 Feb 15, 185(1), 136 - 42 Direct analysis of microbial extracts containing metabolites of ethylenediamine-type antihistamines via high-performance liquid chromatography-thermospray mass spectrometry; Korfmacher WA et al.; The utility of high-performance liquid chromatography-thermospray mass spectrometry (HPLC-TSMS) for the characterization of the ethylenediamine-type antihistamines, pyrilamine, methapyrilene, tripelennamine, and thenyldiamine, and their methylene chloride-extractable microbial metabolites from a biological matrix is demonstrated . Typically, the {M + H}+ ion was detected as the base peak in the TS mass spectra of these compounds . The ethylenediamine-type antihistamine metabolites were detected in an extract of a fungal culture grown in the presence of 5 mg of the antihistamine . A detection limit of 200 ng was observed for the HPLC-TSMS analysis of pyrilamine. Planta Med, 1990 Feb, 56(1), 24 - 6 Pharmacological effects of three phenylpropanoid glycosides from Mussatia; Cano E et al.; The phenylpropanoid glycosides 1 (4-cinamoylmussatioside), 2 (4-dimethylcaffeoylmussatioside), and 3 (4-p-methoxycinnamoylmussatioside) isolated from the methanolic extract of Mussatia sp . showed inhibitory action on ADP-induced rat platelet aggregation . The order of activity was 1 greater than 2 greater than 3 . This antiplatelet effect is likely to be related to the reported inhibition of cAMP-phosphodiesterase . On the other hand, compounds 1-3 had no effect on blood pressure and heart rate, on microbial growth, or on prostaglandin biosynthesis. Vet Microbiol, 1990 Feb, 21(4), 329 - 37 The effect of Mycoplasma bovis on fertilization processes in vitro with bull spermatozoa and zona-free hamster oocytes; Eaglesome MD et al.; The effect of Mycoplasma bovis (Donetta strain) on the ability of bull spermatozoa to interact with zona pellucida-free hamster oocytes was studied in an in vitro assay . Ejaculates of semen from a fertile Holstein bull were used fresh on the day of collection (unextended semen) as well as diluted with egg yolk-citrate and used the following day (extended semen) . The addition of M . bovis to both unextended and extended semen at a mycoplasma to sperm cell ratio of 10:1 significantly reduced sperm penetration rates and the mean number of sperm per penetrated egg . Similarly, the ability of spermatozoa to form pronuclei and the activation of penetrated oocytes were adversely affected by M . bovis . No apparent effect on sperm motility was detected . When M . bovis was added to the oocytes, there was a marked reduction in the sperm penetration rates and fertilization processes suggesting that the organism affects certain oocyte function(s) . The results indicate that the presence of M . bovis in semen or in the female reproductive tract may affect fertilization . Moreover, the in vitro assay with hamster oocytes was found to be useful for demonstrating the effects of contaminating microbial agents on bovine fertilization processes. J Pharmacol Exp Ther, 1990 Feb, 252(2), 526 - 30 Phorbol-12,13-dibutyrate-induced vasoconstriction in vivo: characterization of response in genetic hypertension; Bilder GE et al.; To assess the role of protein kinase C (PKC) in the control of vessel tone in vivo in genetic hypertension, the vascular effects of phorbol-12,13-dibutyrate (PDBu), a PKC activator, was measured in the autoperfused hindlimb of reserpinized spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY) . PDBu infusion (1-3000 ng/kg/min) into the hindlimb elevated perfusion pressure in a dose-related manner . Vasoconstriction response characteristics (latency, T1/2 to peak effect, decay of effect) of PDBu were significantly longer (2- to 10-fold) than that produced by membrane receptor agonists; phenylephrine, SKF 89748, a lipophilic alpha-1 agonist, angiotensin II and 5-hydroxytryptamine . The tonic vasoconstriction induced by PDBu was not antagonized by prazosin, rauwolscine, cyproheptadine, {Sar1lle8}-angiotensin II but was inhibited reversibly by microbial PKC-inhibitors, K252a and staurosporine at concentrations (1.56-2.8 micrograms/kg/min) which did not block vasoconstriction by phenylephrine or 5-hydroxytryptamine . The EC50 for PDBu was identical in SHR and WKY . However, the maximal response to PDBu was significantly greater in SHR compared to WKY . Staurosporine lowered mean arterial pressure equally in SHR (20%) and WKY (17%) but reduced perfusion pressure in SHR (13%) to a slightly greater extent than in WKY (5%) . Unlike the in vivo response, aortic rings removed from SHR were more sensitive to cumulative doses of PDBu than rings from WKY . It is concluded that PDBu-vasoconstriction in vivo is mediated largely through activation of PKC.(ABSTRACT TRUNCATED AT 250 WORDS) Gastroenterology, 1990 Feb, 98(2), 493 - 6 Acute necrotizing esophagitis; Goldenberg SP et al.; Esophagitis of varying degrees and significance is caused by reflux, infections, radiation, and ingestion of chemical agents . A case of necrotizing esophagitis, seen as a black esophagus on endoscopy in a postoperative patient and resulting in long tubular stricture which ultimately required esophagectomy, is reported . Although the course of necrotizing esophagitis may parallel that associated with ischemia, severe caustic injury, or overwhelming infection, its etiology is uncertain . Diminished mucosal defenses, microbial implantation by a nasogastric tube placed perioperatively or sepsis, and transient ischemia with oxyradical formation and resultant reperfusion injury are hypothesized as important causative factors in the pathogenesis of acute necrotizing esophagitis. Quintessence Int, 1990 Feb, 21(2), 141 - 51 Oral ulcerations; Woods MA et al.; Ulcerations are common occurrences in the mouth . Causes include physical trauma, radiation, chemical injury, and microbial infection (bacterial, viral, and fungal) . Some ulcerations, such as recurrent aphthous stomatitis, Behcet's syndrome, and erythema multiforme, are of uncertain etiology, whereas others (eg, pemphigus, pemphigoid) are apparently of immunologic origin . Malignant neoplasms also may present as ulcerations . Because the natural history and treatment varies with the diagnosis, the practitioner should become familiar with the clinical appearance of the various types of ulcerations so that appropriate treatment can be instituted. Clin Biochem, 1990 Feb, 23(1), 67 - 71 Nitrosamines as potential environmental carcinogens in man; Lin JK; Nitrosamines are ubiquitous in our environment and diet . Many nitroso compounds are carcinogenic in animals and most probably in man . Nitrosamines are formed from the reaction of nitrite with primary, secondary, or tertiary amines in an acid medium . Nitrate should be considered as a nitrosating agent because it can be converted to nitrite by microbial action . Many aliphatic and nitrogen-containing heterocyclic compounds can be nitrosated to form carcinogenic substances . The occurrence in food and in some drugs of several nitrosamines or their nitrosatable precursors is described . Several tobacco-specific nitrosamines have been considered as possible causative agents for human cancer . Nitrosamines may be implicated in the induction of certain human gastric cancers. Nippon Juigaku Zasshi, 1990 Feb, 52(1), 63 - 70 Comparative distribution of immunoglobulin-containing cells in stomach, intestine and associated lymph nodes of cattle; Sato S et al.; Immunoglobulin (Ig)-containing cells were investigated immunohistochemically in the stomach, intestine and associated lymph nodes of clinically normal calves, cows and fetuses to examine mucosal immune responses in the forestomach to rumen microbial flora . IgG-containing cells were observed in the mucosal propria of the forestomach of a 32 day-old, a 37 day-old, two 90 day-old calves, and of all 5 cases of cows . However, no IgA- and IgM-containing cells were observed . Further, no Ig-containing cells were detected in the associated lymph nodes of all calves and cows . Various numbers of Ig-containing cells, predominantly IgG, were observed in the mucosal propria of the abomasum, small intestine and cecum, and in the mesenteric lymph nodes of aged calves and all cows . No Ig-containing cells were observed in any tissues of fetuses . The results suggest that the development of mucosal immune responses in the forestomach may be incomplete as compared with that of the intestine. J Clin Invest, 1990 Feb, 85(2), 563 - 9 Regulation of macrophage function by interferon-gamma . Somatic cell genetic approaches in murine macrophage cell lines to mechanisms of growth inhibition, the oxidative burst, and expression of the chronic granulomatous disease gene; Goldberg M et al.; The importance of oxidative cytocidal mechanisms of phagocytic cells in immune protection against microbial pathogens is uniquely revealed by chronic granulomatous disease (CGD), a genetic deficiency disease of man . This cytocidal response in mononuclear phagocytes is principally regulated by IFN-gamma . A somatic cell genetic approach was taken to select oxidative variants from a cloned murine macrophage cell line, J774.16, which formally permitted us to dissociate three regulatory effects of IFN-gamma on these cells: the antiproliferative effect, the antiviral effect, and production of superoxide anion . Half of the variants defective in O-2 production after phorbol myristate acetate stimulation were also resistant to the antiproliferative effects of IFN-gamma . This result suggests that IFN-gamma-induced growth inhibition and production of cytocidal oxygen intermediates are mediated via a common pathway . The somatic cell genetic approach has allowed us to develop in vitro macrophage models for several forms of CGD . One variant characterized in detail, D9, was unable to produce superoxide after stimulation by phorbol esters . At the molecular level, Northern blot analysis revealed that the mRNA encoding the large subunit of the putative CGD gene product, cytochrome b558, was absent in this variant . Another class of variants constitutively unable to produce O-2 or the cytochrome b558 mRNA could be induced to do so by IFN-gamma . These somatic mutants may be useful models in clarifying the role of the CGD gene product and its regulation in the production of cytocidal oxygen intermediates. Infect Immun, 1990 Feb, 58(2), 427 - 32 Involvement of gamma interferon in antibody enhancement by adjuvants; Odean MJ et al.; In a previous study the adjuvant action of a monophosphoryl lipid A, a nontoxic derivative of endotoxic lipopolysaccharide (LPS), was found to be negated by a monoclonal anti-gamma interferon (anti-IFN-gamma) antibody . The present investigation centered on three other adjuvants of diverse microbial origins, testing for their capacity to affect the release of IFN-gamma as an explanation for their antibody-enhancing action . The adjuvant action of each of the three, a wild-type LPS, synthetic poly(A)-poly(U) complexes, and a synthetic muramyl dipeptide, n-acetylmuramyl-L-alanyl-D-glutaminyl-n-butyl ester (murabutide), was transferable by adjuvant-stimulated T cells to normal spleen cells on coculture . Supernatant fluids from these T cells contained increased levels of IFN-gamma . Addition of a monoclonal anti-IFN-gamma antibody to adjuvant-stimulated spleen cell cultures reduced the adjuvant action by approximately one-half . Removal of natural killer cells from spleen cell populations prior to culture with antigen had no effect on the enhancement induced by LPS and monophosphoryl lipid A . It was concluded that the enhancement induced by the adjuvants LPS, poly(A)-poly(U), and murabutide is mediated in part by their action on T cells resulting in release of IFN-gamma suggesting activation of a common transmembrane signal. J Formos Med Assoc, 1990 Feb, 89(2), 115 - 20 Short-course treatment of bacteremia with ceftriaxone monotherapy; Wang LS et al.; The efficacy of short-course ceftriaxone monotherapy in treatment of bacteremia was evaluated in an open protocol . Patients with laboratory-proven bacteremia were randomly treated with one of three dosing schedules for a duration of 5 to 7 days . Fifty-seven (62%) out of the 92 evaluable infections had successful results . Successful responses were seen in 20 (59%) out of 34 infections given 4 g every 24 hours, 15 (54%) out of 28 given 2 g every 12 hours, and 22 out (73%) of 30 given 2 g every 24 hours . The results showed no significant differences . The cases evaluated as failures were largely due to infections with resistant organisms or inadequate drainage of the primary infectious foci . Forty-nine (94%) of the 52 infections had successful results with one of the short-course treatment regimens, provided that they had no factors indicative of a poor prognosis . We stress the importance of anti-microbial susceptibility and adequate removal of the primary foci in the treatment of bacteremia . Our experience indicates that once-daily administrations of 2 g ceftriaxone as monotherapy is preferred for short-course treatment of bacteremia since it is equally effective, but more economical than higher dose regimens. J Periodontol, 1990 Feb, 61(2), 95 - 102 Morphologic and histochemical characteristics of the dental cuticle in teeth affected by prepubertal periodontitis; Lopez NJ et al.; A study was undertaken to determine the nature and composition of the cuticle found in teeth with generalized prepubertal periodontitis (PP) . This was accomplished by using histological and histochemical methods on decalcified specimens . Forty-six permanent teeth which were extracted from three prepubertal periodontitis patients (siblings) were used . Nineteen of the 46 teeth were obtained with the facial or interdental gingiva . As a control, 20 healthy teeth extracted from 10 children for orthodontics reasons, and 22 teeth affected by terminal adult periodontitis (AP), were used . All the teeth with PP showed a thick coat covering the root surface from the cemento-enamel junction to the junctional epithelium . In some teeth the cuticle extended a few microns coronally to the cemento-enamel junction . The cuticle had a thickness which varied between 10 to 80 microns . It usually presented a very regular surface in the coronal portion of the root, and showed laminations suggesting appositional growth . In the middle and apical portions of the root exposed to the pocket, the cuticle was lobular with a very irregular surface and was covered with a thick microbial plaque . The staining reactions indicated that the cuticle was made of proteins probably derived from the inflammatory exudate . None of the healthy teeth examined nor those affected by AP showed a cuticle similar to those with PP . The cuticle formed on the teeth with PP appears to be an abnormal structure of proteinaceous nature, characteristic of these teeth, and may possibly play a role in the pathogenesis of the disease. Cancer Res, 1990 Feb 1, 50(3), 533 - 8 Regulation of the epidermal growth factor receptor by growth-modulating agents: effects of staurosporine, a protein kinase inhibitor; Friedman B et al.; Staurosporine is a potent microbial inhibitor of a number of protein kinases, including protein kinase C, cyclic AMP-dependent kinase, and the tyrosine kinase pp60src . We have used staurosporine to investigate the role of phosphorylation in the regulation of the epidermal growth factor (EGF) receptor in both human epidermal carcinoma A431 cells and mouse Swiss 3T3 fibroblasts . We report here that staurosporine treatment causes enhancement in high affinity EGF binding and a decrease in the phosphorylation state of the unstimulated receptor at a number of residues, including threonine 669 . Staurosporine also antagonizes the inhibition of high affinity EGF binding and the increase in phosphorylation state of the unstimulated EGF receptor by phorbol esters and the calcium ionophore A23187 . Staurosporine is an effective inhibitor of the EGF-stimulated receptor tyrosine kinase in vitro and thus does not enhance EGF stimulation of EGF receptor autophosphorylation in vivo . These results suggest that phosphorylation plays a major role in the regulation of the high affinity binding state of the EGF receptor in both unstimulated and mitogenically activated cells. J Immunol, 1990 Jan 15, 144(2), 420 - 4 The use of transfected fibroblasts and transgenic mice establishes that stimulation of T cells by the Mycoplasma arthritidis mitogen is mediated by E alpha; Cole BC et al.; Mycoplasma arthritidis produces a soluble protein which is active for murine and human lymphocytes when presented by Ia-bearing accessory cells . By using fibroblasts transfected in vitro with various class II Ag, we demonstrated that presentation of the M . arthritidis mitogen (MAM) to T cells was mediated by E alpha-containing molecules . We also showed that splenocytes from transgenic mice expressing E alpha heterozygously (B10.TRG E alpha+) or homozygously (B10.E alpha TG +/+) underwent a similar proliferation in response to MAM as compared with the failure of control B10.TRG E alpha- splenocytes to respond to MAM . Although splenocytes from inbred C3H and CBA mice exhibited much higher proliferative responses to MAM than did those from B10.TRG.E alpha+ or B10.E alpha TG +/+ mice, flow cytometry showed similar levels of E alpha expression . Furthermore, gamma-irradiated splenocytes from B10.TRG E alpha + mice presented MAM to T hybridoma cells with a similar efficacy as did splenocytes from C3H mice . The lesser response to MAM of lymphocytes from the E alpha transgenic mice as compared with those from C3H and B10.K mice was likewise not due to differential expression of their V beta TCR . We conclude that presentation of MAM to T cells is accomplished by E alpha-containing molecules . The studies also suggest that the conserved, nonpolymorphic regions of class II molecules may play an important role in host immune response to microbial products. Curr Top Microbiol Immunol, 1990, 150, 129 - 57 Visualization of the bacterial polysaccharide capsule; Bayer ME; The highly hydrated capsule of E . coli strains is composed of a large number of polysaccharide fibers of which the thinnest measure about 2 nm in width . The fibers may span the entire distance from the outer membrane to the outer rim of the capsule and show a propensity to associate with each other to form thicker filaments . Presence of thick filaments may also indicate a partial collapse of the capsular organization due to removal of water . The in vivo capsule represents a relatively open structure with the negatively charged polysaccharide fibers permitting the binding of large quantities of water and ions, and providing intracellular space for diffusing molecules to access the envelope membranes even in conditions of high cell density . Negative charge and steric hindrance of the polysaccharide strands protect the cells against attack by a large variety of harmful macromolecules and against infection by most bacteriophages . Two types of procedure have been most successful in maintaining the size and overall structure of the capsule: (a) the interaction of cationic molecules with the in vivo capsule, and (b) the use of antibody to stabilize capsules for subsequent dehydration and plastic embedding . A further type of potentially useful procedure, cryofixation and cryosubstitution, has shown interesting results in a number of cases . These techniques are expected to play a significant role in structural studies in the near future . The sites of export of capsular antigen have been described in earlier conventional electron microscopic studies . Data obtained from the recent technique of "on-section" labeling support the model that both the capsular antigen and the O antigen are assembled at junctions of the inner and outer membrane . It is anticipated that one will be able to discern in greater ultrastructural detail the membranes at which the antigen is translocated . Novel membrane fixation and isolation techniques will have to be established and employed in a combination of sensitive microscopic techniques and immuno- and enzyme localization methods . These developments will make it possible to explore questions pertaining to the maintenance and structural organization of microbial capsules and the functional interaction of polysaccharides with natural surfaces, man-made substances and drugs. Dent Clin North Am, 1990 Jan, 34(1), 1 - 11 Chemotherapy . A viable periodontal treatment modality? Deasy MJ. Because bacterial plaque is composed chiefly of micro-organisms, use of chemotherapeutic agents directed against a susceptible flora would seem a conceptually valid therapeutic modality, in terms of inhibition of plaque, for the prevention and treatment of periodontal disease . The objective of treatment largely dictates the modality used . If, for example, the philosophy of treatment is elimination or reduction of pocket depth, chemotherapy against supragingival plaque may complement mechanical oral hygiene in the absence of a plaque-free environment . On the other hand, access to the subgingival flora can only be achieved through systemic administration of drugs or the use of controlled delivery systems . Notwithstanding their potential benefit as adjunctive therapy, in cases of refractory periodontitis and juvenile periodontitis in which elimination of Actinobacillus actinomycetemcomitans by mechanical debridement alone is extremely difficult, the potential for adverse reactions from the administration of antibiotics must be weighed and their use, in general, considered unwarranted . The dynamics of the inter-relationship between supragingival and subgingival plaque necessitates control of both for the successful treatment of periodontal disease . Although there are chemical agents that have been shown to be effective in the treatment of gingivitis, the evidence pertaining to their effectiveness in the treatment of periodontitis, either alone or in conjunction with conventional therapy, is inconclusive . If specific microbial floras are associated with different forms of periodontal disease, chemotherapeutic agents to which such micro-organisms are susceptible would have to be employed for their elimination . Until accurate predictors of disease activity--including definitive indicators of which particular sites are, at any one time, actively undergoing attachment loss--are available, the use of chemotherapeutic agents directed at the subgingival flora appears extremely limited and impractical . However, with the development of predictors of disease activity, including sophisticated methods of determining even small increments of attachment loss, new drugs, and a better understanding of subgingival ecologic systems, chemotherapy may yet play a significant role in the treatment of periodontal disease. Int J Artif Organs, 1990 Jan, 13(1), 44 - 50 Peritoneal leucocyte response to bacterial peritonitis in patients receiving peritoneal dialysis; Shah GM et al.; We evaluated the quantitative peritoneal leucocyte response to antibiotic therapy in 25 CAPD patients with 57 episodes of bacterial peritonitis . Eighty-eight percent of the peritonitis episodes were initially treated with a first generation cephalosporin, but results of microbial sensitivity studies led to a change in the initial antibiotic regimen in 23 episodes . Overall, 47/57 (82%) episodes were cured by antibiotic therapy alone (responders), while 10/57 (18%) required removal of the peritoneal catheter as a curative procedure (nonresponder) . Neither the duration of symptoms on initial presentation nor the status of being a nonresponder could be related to the baseline peritoneal leucocyte values, either the total (PLC) or polymorphonuclear counts (PMN) . Since the baseline PLC and PMN showed a 500-fold variation, subsequent changes were expressed as a percent {PLC (%) and PMN-PLC (%)} of the baseline value . On day 3 of peritonitis, PLC (%) and PMN-PLC (%) were less in responders (26% and 10%) than nonresponders (251% and 254%) (p less than 0.001) . Differentiation between responders and nonresponders based on PLC (%) and PMN-PLC (%) was associated with a high degree of sensitivity (90%) and specificity (90%) . Similar results were obtained for day 4 . These data suggest that the temporal pattern of PLC and PMN, when expressed as a percentage of the baseline value, may be useful in predicting those episodes of peritonitis which require removal of the peritoneal catheter. Comp Biochem Physiol B, 1990, 96(3), 475 - 82 Distribution of branched-chain fatty acid in the skin surface lipid of laboratory animals; Oku H et al.; 1 . The distribution of the branched-chain fatty acid (BCFA) was studied in skin surface lipids of laboratory animals (rat, mouse, hamster and rabbit) and the experimental animal for the study of the metabolic fate of BCFA was chosen . 2 . The monoester fraction resistant to microbial degradation was the index of which fatty acids were identified and the compositions were analyzed by capillary gas chromatography and mass spectrometry (GC-MS) . 3 . The contents of monoester fractions in rat, mouse, hamster and rabbit were 78.9, 15.9, 30.4 and 45.6% of the total skin surface lipid, respectively . 4 . BCFAs were exclusively identified to be either iso- or anteiso-series type by means of mass spectrometry . 5 . The sum of iso- and anteiso-acid was the highest in hamster comprising 53% in male and 38% in female of the monoester acid . 6 . Sex related differences of BCFA concentration were not so evident in the other three species . 7 . BCFA contents in the monoester fractions were as follows: rat 32%, mouse 25% and rabbit 3% . 8 . Concentrations of iso-series fatty acid were consistently higher than that of anteiso-series type in all animals studied . 9 . Abundance of 2-hydroxy fatty acid in the rabbit monoester fraction was noted for the first time . 10 . Suitability of these laboratory animals for the study of BCFA metabolism was discussed. J Basic Microbiol, 1990, 30(4), 297 - 300 Selective and rapid solubilization of the microbial membrane enzyme aldehyde dehydrogenase; Hommel R et al.; An improved solubilization procedure for the membrane-bound quinoprotein aldehyde dehydrogenase from Acetobacter rancens CCM 1774 was established . After the first solubilization of membrane enzymes by Brij 35 which provided important extraction of membrane proteins other than aldehyde dehydrogenase, the application of Trition X-100 resulted in an almost 20-fold purification of quinoprotein aldehyde dehydrogenase . The optimal solubilization was closely connected with definite detergent/protein ratios. Med Lab Sci, 1990 Jan, 47(1), 42 - 5 Use of a bacterial sampler for rapid transfer of microvolumes into microplates; Rawlinson J et al.; A method has been devised to transfer very small volumes of serum from microplates prepared during routine screening of blood into microplates containing diluent . Simultaneous transfer of 96 samples is achieved without the need for disposable tips, while still avoiding carry-over between different plates . Using this method a mean transfer volume of 0.9 microliters (cv 8.9%) was obtained, which lent itself conveniently to testing for high-titre anti-microbial antibodies for which high dilution factors are required. Probl Tuberk, 1990, (3), 36 - 41 {Identification of Mycobacteria species by liquid-gas chromatography}; Pinchuk LM et al.; Principles and characteristic features of gas chromatographic indentification of Mycobacterium from the fatty acid composition were considered . The results of their differentiation by gas chromatography agree with Myco . indentification according to the complex of morphological, cultural and biochemical, and other characteristics . Copyrolysis has a number of advantages compared to the routine identification techniques, i.e . it reduces the time needed for the analysis down to 2-3 hours; allows one to use small portions of microbial mass; and provides for a complete automation of the procedure . The advisability of putting the gas chromatographic identification of Myco . species into practice of the antituberculosis medical and veterinary institutions is pointed out. Vopr Virusol, 1990 Jan-Feb, 35(1), 64 - 8 {Characteristics of Namalwa cells--a substrate for production of human interferon}; Shukhmina NR et al.; The properties of lymphoid Namalwa cell line propagated at the USSR Academy of Medical Sciences Research Institute of Viral Preparations for interferon production are described . The scanning and transmissive electron microscopy studies of the cells showed their morphological stability and the absence of microbial contamination . The 46-48-chromosome cells comprised 85% of the population, hypodiploid cells (44-45 chromosomes), 9%, tetraploid and hypertetraploid cells, 3% . Spontaneous aberrations were detected in 3% of the chromosome . Inoculation of the cells into unsuppressed laboratory animals (rabbits, guinea pigs, adult or suckling mice) or chick embryos did not cause the development of any pathological process . Namalwa cells were shown to produce interferon after multiple (up to 4 times) induction with Newcastle disease virus. Vestn Akad Med Nauk SSSR, 1990, (2), 46 - 8 {Transcription of nucleoplasmatic and nucleolar sites of DNA sensitive to the protease inhibitor antipain}; Iarygin VN et al.; Age-related changes in the transcriptional activities of Purkinje cells chromatin and sympathetic cranial cervical ganglion under the influence of morphine and some natural and synthetic peptide compounds were found . It was shown that at different stages of the ontogenesis, morphine was capable of increasing the template activity of nucleolar and/or extranucleolar chromatin, and that this process was inhibited by antipain . The findings suggest the presence of DNA sites in the eucaryotic genome, that are induced by the protease mechanism and are likely to be similar to the SOS-genes of procaryotes . The SOS-genes of procaryotes are activated under unfavourable conditions and promote the survival of the microbial population, while in eucaryotes these genes are believed to provide the formation of definite cell populations whose composition is the most adequate for the living conditions of an adult organism. Cornea, 1990, 9 Suppl 1, S59 - 61; discussion S62-3 A review of relative risks associated with four types of contact lenses; Bailey CS; This paper reviews the data of Frank et al . in the light of increasing concern over the safety of contact lenses used for extended wear . Relative risks were calculated for four types of contact lenses (CLs): extended wear soft, daily wear soft, rigid gas-permeable (RGP), and polymethylmethacrylate (PMMA) lenses--worn by a group of patients who presented themselves for emergency ocular treatment . The cases comprised 329 CL wearers who were found to have lens related metabolic disorders, toxic or hypersensitivity reactions, cornea abrasions, microbial keratitis, or some other lens-induced problem . Controls comprised 64 CL wearers whose ocular problems were unrelated to lens use . It was found that extended wear soft lenses were nearly 7 times more likely to be associated with an ocular disorder than PMMA hard lenses, and approximately 3.4 times more likely than daily wear soft lenses . Furthermore, extended wear soft lenses were nearly 5 times more likely to be linked with microbial keratitis than daily wear soft lenses, and approximately 7.5 times more likely than RGP lenses . Metabolic disorders were also more common with extended wear lenses (relatively risk: 3.3) than with either RGP (1.8) or daily wear soft lenses (2.0) or PMMA lenses (1.0) . If the association between extended wear soft lenses and ocular complications is borne out in large population studies, eye-care professionals may need to reconsider the wisdom of prescribing these lenses for the cosmetic correction of vision. Toxicon, 1990, 28(1), 101 - 5 Effect of storage temperature on the stability of the liquid polyvalent antivenom produced in Costa Rica; Rojas G et al.; The effect of storage temperature on the stability of the liquid polyvalent (crotaline) antivenom produced at the Instituto Clodomiro Picado, Costa Rica, was studied during a twelve-month period . The following parameters were evaluated: neutralizing potency against lethal activity of Bothrops asper venom; protein and phenol concentrations; pH; turbidity; safety; and sterility . Analyses were performed each month on different samples of a batch, stored at 4, 23, 30 and 37 degrees C . No significant (P greater than 0.1) variations occurred in potency, protein and phenol concentrations, pH, sterility or safety, at any of the storage temperatures during the study period . However, visual inspection revealed a moderate increase in turbidity of the samples stored at 23, 30 and 37 degrees C, at nine, four and three months, respectively . Culture of samples excluded the possibility of microbial contamination of the product leading to turbidity . Chromatographic and electrophoretic analyses demonstrated that turbidity was caused by the formation of heterogeneous protein aggregates of high molecular weight . Present results support the conclusion that, although storage temperature (up to 37 degrees C for twelve months) does not alter antivenom potency, it significantly influences the formation of protein aggregates . This phenomenon can be prevented by recommending the storage of antivenom at refrigeration temperature. Stomatologiia (Mosk), 1990 Jan-Feb, 69(1), 29 - 31 {A difference in the mechanisms of the development of periodontitis}; Mashchenko IS; The study based on immunological and epidemiological evaluation of large groups of population has revealed the factors responsible principally for periodontitis pattern . They are: 1) microbial and tissue sensitization, 2) immune defences, 3) disturbed microcirculation in periodontal tissues . In view of various causes underlying periodontitis it is advisable to take them into consideration when evaluating diagnostic data and deciding on indications for immunocorrective therapy. Nahrung, 1990, 34(1), 37 - 46 {Water binding of adsorptive immobilized lipases}; Loose S et al.; It is supposed that not only the total water content of lipase preparations but more their state of water binding is of technological importance in enzymatic interesterification reactions in systems nearly free from water . The isotherms at 65 degrees C of two microbial lipases immobilized on various adsorbents as well as different adsorbents themselves are shown . The water binding capacity in the range of water content of technological interest decreases from the anion exchange resin Amberlyst A 21 via nonpolar adsorbent Amberlite XAD-2 to kieselguhr Celite 545 . It is demonstrated that water binding by lipases is depending on temperature but is also affected by adsorptive immobilization . Adsorptive immobilized lipases show hysteresis, which is very important for preparing a definite water content of the enzyme preparations. J Dairy Sci, 1990 Jan, 73(1), 142 - 8 Influence of synchronizing protein and starch degradation in the rumen on nutrient utilization and microbial protein synthesis; Herrera-Saldana R et al.; A 4 x 4 Latin square design with four multiparous cows in midlactation fitted with duodenal cannulae was used to determine the effect of synchronization of protein and starch degradation in the rumen on nutrient availability in lactating cows . As major starch and protein sources, diets contained: barley plus cottonseed meal; barley plus brewers dried grains; milo plus cottonseed meal; and milo plus brewers dried grains . Experimental periods were 12 d and consisted of 8 d adjustment and 4 d collection . Chromium oxide was used as the marker to determine digestibility and nutrient flow from the rumen . Microbial protein synthesis was estimated from nucleic acid content in duodenal samples . Apparent and corrected rumen digestibilities of DM, organic matter, CP, and starch were higher for diets containing barley than milo but were not affected by protein source . For diets containing barley and milo, starch digested postruminally averaged 820 and 2190 g/d and percentage digestibility was 70 and 77% . No difference among diets was found in DM, organic matter, and CP flow to the small intestine; however, microbial N synthesis was higher in diets containing barley than in diets containing milo. J Submicrosc Cytol Pathol, 1990 Jan, 22(1), 79 - 90 Ultrastructural comparative distribution of carbohydrates in human tracheal and frog palate mucosa using neuraminidase and lectin-colloidal gold complexes; Plotkowski MC et al.; We have compared, at the ultrastructural level, the carbohydrate structure of glycoconjugates of the different types of secretory cells of the human tracheal mucosa (HTM) and the frog palate mucosa (FPM), proposed as a model for studying bacterial adherence to mucus-coated respiratory epithelium . In addition to reactivity with Concanavalin A and Lens cullinaris agglutinin, reactivity of Epon-embedded HTM and FPM secretory granules was studied by transmission electron microscopy using neuraminidase-gold complex and colloidal gold-adsorbed lectins with affinity for sugar residues of human mucins, namely the following: Helix pomatia, Lotus tetragonolobus, Ricinus communis II, Wheat germ and Limax flavus agglutinins . The affinity of HTM and FPM mucous and serous cells for the different colloidal-gold complexes was very similar, however Limax flavus agglutinin labelled only HTM and not FPM secretory granules . The FPM mucous and serous secretory granules were nevertheless intensely labelled by the neuraminidase-gold complex, demonstrating the presence of sialic acid residues . The close ultrastructural and histochemical similarities between HTM and FPM suggest that the FPM may be a valuable model for studying the specific interaction between microbial lectins and mucus glycoproteins in the bacterial adherence phenomenon. Pathol Biol (Paris), 1990 Jan, 38(1), 36 - 42 {Interleukins and inflammation}; Cavaillon JM; Interleukins (IL) are a heterogeneous class of cytokines involved in activation of T lymphocytes (IL-1, 2, 4, 6 and 7), B lymphocytes (IL-1, 2, 4, 5, 6 and 7), and macrophages (IL-1 and 4), and hematopoiesis (IL-1, 2, 3, 4, 5, 6 and 7), acting either by themselves, or as co-stimulator factors . Interleukin-1 (IL-1 alpha and IL-1 beta) is induced by different signals including microbial products; it mediates various events occurring during inflammation (e.g . fever, osteolysis, leucopenia, hypotension, hyperalgia, etc...) . Such mechanisms are often the consequences of the induction by IL-1 of lipid mediators (e.g . prostaglandins, platelet activating factor, etc) . IL-1 often acts synergistically with Tumor Necrosis Factor during the pro-inflammatory process . IL-1 as well as microbial products induces the production of interleukin-6 and interleukin-8 . IL-6 also plays a role in inflammation, mainly as an inducer of acute phase proteins synthesis by hepatocytes . IL-8 has chemotactic and activating properties for neutrophils. J Steroid Biochem, 1990 Jan, 35(1), 107 - 13 Inhibition of microbial cholesterol oxidases by dimethylmorpholines; Hesselink PG et al.; Cholesterol oxidase is a potentially important enzyme in steroid transformations, catalysing the conversion of 3-hydroxy-5-ene steroids to 3-keto-4-ene derivatives via a 3-keto-5-ene intermediate . Morpholine derivatives, especially fenpropimorph and tridemorph, were found to block selectively the isomerisation activity of cholesterol oxidases isolated from Nocardia erythropolis, Streptomyces sp., Pseudomonas testosteroni and Schizophyllum commune . These enzymes differ strongly in physical characteristics and catalytic behaviour . The effectiveness of the inhibitors varied with the cholesterol oxidase tested . Fenpropimorph was most effective with each of the 4 enzymes, 50 mg/l inhibiting about 50% of the enzyme activity . Inhibition was instantaneous and followed a reversible competitive mechanism in Streptomyces sp . and a reversible non-competitive mechanism in Nocardia erythropolis and Schizophyllum commune . An irreversible type of inhibition was observed for P . testosteroni cholesterol oxidase. Am Rev Respir Dis, 1990 Jan, 141(1), 179 - 85 Direct cytotoxicity of polymorphonuclear leukocyte granule proteins to human lung-derived cells and endothelial cells; Okrent DG et al.; Neutrophils, in the course of defending the host against microbial invasion, release a potent arsenal of proteins that can potentially damage host tissues . Defensins are major peptides of human polymorphonuclear leukocyte (PMN) granules and are both broadly microbicidal and cytotoxic to several tumor cell lines . To determine whether these peptides could play a role in neutrophil-mediated lung injury, we examined the cytotoxicity of defensins and other PMN granule proteins in a chromium release assay with human lung-derived cell lines MRC-5 (lung fetal fibroblast), A549 (lung adenocarcinoma with features of alveolar epithelium), and primary cultures of human umbilical vein endothelial cells (HUVEC) . Crude fractionation of an acid extract of human PMN granules yielded four fractions A-D . Only fraction D (containing mostly defensins) was significantly cytotoxic to all three target cells . In contrast, fraction A (containing myeloperoxidase and lactoferrin) and fraction C (containing lysozyme) had little effect, and fraction B (containing chiefly cathepsin G and elastase) was only injurious to endothelial cells . The cytotoxicity of whole PMN granule extracts on pulmonary epithelial and fibroblast targets could be completely accounted for by their defensin content . Fraction D- and defensin-mediated cytotoxicity was concentration dependent, required at least 10 to 12 h to become manifest, and was inhibited by serum . The role of these peptides in lung damage during acute and chronic inflammation deserves further study. Adv Biochem Eng Biotechnol, 1990, 42, 97 - 131 Application of immobilized growing cells; Tanaka A et al.; Immobilized living and growing cells are attracting worldwide attention because these biocatalysts have self-proliferating and self-regenerating properties of catalytic systems and are able to catalyze efficiently multifunctional and multistep reactions involving coenzyme regeneration . This article summarizes the application of microbial, plant, and mammalian cells, genetically improved or not, immobilized by different methods to the production of amino acids, organic acids, antibiotics, steroids, medicines, enzymes, bioactive peptides, etc., emphasizing the recent results . Effects of the gel properties on the efficient performance of bioprocesses are also discussed. Biopolymers, 1990, 30(3-4), 239 - 56 The solution conformations of ferrichrome and deferriferrichrome determined by 1H-NMR spectroscopy and computational modeling; Constantine KL et al.; We have applied computational procedures that utilize nmr data to model the solution conformation of ferrichrome, a rigid microbial iron transport cyclohexapeptide of known x-ray crystallographic structure {D . van der Helm et al . (1980) J . Am . Chem . Soc . 102, 4224-4231} . The Al3+ and Ga3+ diamagnetic analogues, alumichrome and gallichrome, dissolved in d6-dimethylsulfoxide (d6-DMSO), were investigated via one- and two-dimensional 1H-nmr spectroscopy at 300, 600, and 620 MHz . Interproton distance constraints derived from proton Overhauser experiments were input to a distance geometry algorithm {T . F . Havel and K . Wuthrich (1984) Bull . Math . Biol . 46, 673-691} in order to generate a family of ferrichrome structures consistent with the experimental data . These models were subsequently optimized through restrained molecular dynamics/energy minimization {B . R . Brooks et al . (1983) J . Comp . Chem . 4, 187-217} . The resulting structures were characterized in terms of relative energies and conformational properties . Computations based on integration of the generalized Bloch equations for the complete molecule, which include the 14N-1H dipolar interaction, demonstrate that the x-ray coordinates reproduce the experimental nuclear Overhauser effect time courses very well, and indicate that there are no significant differences between the crystalline and solution conformations of ferrichrome . A similar study of the metal free peptide, deferriferrichrome, suggests that at least two conformers are present in d6-DMSO at 23 degrees C . Both are different from the ferrichrome structure and explain, through conformational averaging, the observed amide NH and CH alpha multiplet splittings . The occurrence of interconverting peptide backbone conformations yields an increased number of sequential NH-CH alpha and NH-NH Overhauser connectivities, which reflects the mean value of r-6 dependence of the dipolar interaction . Our results support the idea that, in the case of structurally rigid peptides, moderately accurate distance constraints define a conformational subspace encompassing the "true" structure, and that energy considerations reduce the size of this subspace . For flexible peptides, however, the straight-forward approach can be misleading since the nmr parameters are averaged over substantially different conformational states. J Med Vet Mycol, 1990, 28(4), 303 - 15 An extended QBASIC program for the normalization and computation of whole-cell protein profiles and the application to clinically important Candida species; Smit EJ et al.; The computer program described enables a rapid calculation of relative molecular masses of proteins from different yeasts and microbial pathogens, by interpolation from a molecular weight calibration curve that comprises stepwise linear regression between the protein bands produced by the internal standards . A similarity matrix can then be produced, taking into account variations between calculated molecular masses caused by small differences in bandwidths and/or positions of specific protein bands . This program has been applied to different Candida species and the similarity data obtained further analysed numerically utilizing CLUSTAN II on a SPERRY 1100 multi-processor. Adv Microb Physiol, 1990, 31, 183 - 223 Microbial stress proteins; Watson K; There is general agreement that a function, perhaps the major function, of stress proteins under normal physiological conditions is to help assembly and disassembly of protein complexes and to catalyse protein-translocation processes . It remains unclear, however, as to what role these processes play in stressed cells . It could be that cells under stress produce abnormal, misfolded or otherwise damaged proteins and that increased synthesis of stress proteins is required to counter protein modifications . A role for stress proteins in recovery of cells from stress, as opposed to a role in helping cells to withstand a lethal stress, is thus suggested . The intracellular location of stress proteins, in the unstressed and stressed cell, is worthy of further studies . Members of the hsp70 family are associated with the cytosol, mitochondria and endoplasmic reticulum . There is evidence, particularly from studies on mammalian cells (Tanguay, 1985; Welch and Mizzen, 1988; Arrigo et al., 1988), that following stress hsps migrate to various cellular compartments and subsequently delocalize after stress . However, there is little comparable data from microbial systems for this phenomenon (e.g . Rossi and Lindquist, 1989) . The question as to the role of stress proteins in the transient acquisition of thermotolerance remains to be answered . It is insufficient to equate the kinetics of stress-protein synthesis with acquisition of thermotolerance . Quantitative data on the amount of stress protein present at various times, including the recovery period, is required . The demonstration that microbial stress proteins are important antigenic determinants of micro-organisms causing major debilitating diseases in the world is an exciting observation . Studies on the interplay of pathogen and host, both carrying similar antigenic hsp determinants, will be a challenging area for future research . It is likely that E . coli and Sacch . cerevisiae, with their well-established biochemical and genetic properties, will continue to be the experimental systems of choice for studies on stress proteins . On the other hand, it is encouraging that studies on other micro-organisms have expanded in the past few years and have made substantial contributions towards our understanding of the stress response . The ubiquitous nature of the stress response and the remarkable evolutionary conservation of the stress proteins continue to be attractive areas for research. Reprod Nutr Dev, 1990, 30(4), 533 - 40 Microbial degradation in the rumen of wheat straw and anhydrous ammonia treated wheat straw observed by electron microscopy; Grenet E et al.; With the exception of the phloem and the crown of the parenchyma, which borders the medullary lacuna, the walls of the tissues of both treated and untreated straw were lignified . The walls of the treated straw were not fluorescent in the ultraviolet probably because the treatment had modified the phenolic acids . They also had a stronger reaction to Schiff reagent particularly in the sclerenchyma indicating that their polysaccharides were more accessible . The tissues of the treated straw degraded faster in the rumen . The walls of the sclerenchyma of the treated straw were attacked by micro-organisms . Both treated and normal straw were abundantly colonized by rumen fungi, especially in the sclerenchyma . The increase in the digestibility of the treated straw was due to the greater access the micro-organisms had to the polysaccharides of the lignified walls. Adv Exp Med Biol, 1990, 264, 79 - 84 Effects of glycyl-histidyl-lysyl chelated Cu(II) on ferritin dependent lipid peroxidation; Miller DM et al.; The copper binding tripeptide, glycyl-L-histidyl-L-lysine {GHK:Cu(II)} has a plethora of biological effects related to the wound healing process . The presence of iron complexes in damaged tissues is detrimental to wound healing, due to local inflammation, as well as microbial infection mediated by iron . To test if the wound healing properties of GHK:Cu(II) are due to an affect on iron metabolism, we examined the effects of GHK:Cu(II) on iron catalyzed lipid peroxidation . GHK:Cu(II) inhibited lipid peroxidation only if the iron source was ferritin . Whereas GHK:Cu(II) inhibited ferritin iron release it did not exhibit significant superoxide dismutase-like or ceruloplasmin-like activity . We propose that GHK:Cu(II) binds to the channels of ferritin involved in iron release and physically prevents the release of Fe(II) . Thus, a biological effect of GHK:Cu(II), possibly related to wound healing, may be the inhibition of ferritin iron release in damaged tissues, preventing inflammation and microbial infections. Nahrung, 1990, 34(8), 701 - 17 {The characterization of microbial lipases . 1 . The determination of lipase activity}; Bariszlovich M et al.; In the selection of an appropriate method for activity determination of lipases existing technical equipment, kind of enzymes, number of samples investigated (e.g . in routine analysis), and expected sensitivity range have to be taken into account . Titrimetric methods and above all copper salt methods with their high detection sensitivity are the most suitable procedures for activity determination of lipases used in laboratories and institutions without equipment for radiochemical analysis. Cytobios, 1990, 62(250-251), 191 - 9 A further study on the regulation of microbial proteases; Kuo WN et al.; Various agents were tested for their effects on microbial proteases, which activity was monitored by the analysis of cleaved peptide bands in SDS-polyacrylamide gel electrophoresis . Using casein as a substrate, fungal protease (type XIX) was inhibited by the phenyl methyl sulphonyl fluoride, chymostatin, antipain and leupeptin, while bacterial protease (type XXVI) was inhibited by phosphatidyl glycerol, phosphatidyl inositol and sphingosine . MS2 RNA exerted minor inhibition on the bacterial proteolysis of regulatory subunits of cyclic AMP-dependent protein kinase (A-PK) . The cleavage of DNA binding protein by both proteases was inhibited, in the presence of MS2 RNA and lambda DNA . In comparison, phosphatidyl serine slightly stimulated the fungal protease on the cleavage of ribonuclease T1 . RNA polymerase is a good substrate of the bacterial protease as indicated by the generation of multiple cleaved peptide fragments, whereas alkaline phosphatase is not susceptible to proteolysis. Cancer Detect Prev, 1990, 14(4), 471 - 81 Tumor-cytolytic human macrophages cultured as nonadherent cells: potential for the adoptive immunotherapy of cancer; Helinski EH et al.; Tumor-cytolytic lymphokine (e.g., interleukin-2; IL-2)-activated killer cells are currently being evaluated in IL-2/LAK cell adoptive immunotherapy regimens for the treatment of cancer . Monocyte-derived macrophages (M phi) are also known to be efficient tumor killer cells; accordingly, M phi that have been activated in vitro may also be of therapeutic merit . However, attempts to cultivate M phi for morphological and functional studies have often been compromised because M phi adhere rapidly and tenaciously to cultureware . Studies that we have conducted to address this problem have proven successful in developing procedures for the long-term cultivation of non-adherent immunocompetent M phi in serum-free medium using petri dishes containing a thin Teflon liner . The utility of this technology is documented by the results of studies presented herein in which light and scanning electron microscopy was used to analyze tumor-cytolytic human M phi . In these experiments, we demonstrated that nonadherent immunocompetent human M phi can be prepared for detailed examinations of their pleomorphic membrane architecture . Moreover, nonadherent human M phi could readily be collected for preparing conjugates of M phi and tumor cells . It is anticipated that this technology should prove useful for future structure-function studies defining the topographical location and spatial distribution of antigens and receptors on M phi membrane ultrastructures, particularly the microvilli-like projections that bridge together an immunocompetent effector M phi and target cell (e.g., tumor cells and microbial pathogens) and which provide the physical interaction required for the initial phases of a cellular immune response that includes antigen recognition and cell-to-cell adhesion. Biosens Bioelectron, 1990, 5(4), 273 - 89 Oscillometric instrument for the non-invasive detection of low-level microbial activity . Part 2: Growth characteristics, detection limits and impedimetric assays; Cossar JD et al.; Instrument performance and application was evaluated with a variety of microbial suspensions . Data were compared with those obtainable from current commercial apparatus in terms of resolution and detection times . Trials with growing and non-growing cultures indicated periodic synchronous ion exchange processes . Media composition, particularly salt and nutrient ratios, remain crucial to early and rapid detection of viable microbial activity at low concentrations . With appropriate conditions very significant improvements in detection times with typical detection thresholds of 300 min for start concentrations of 10(2) are shown . It is concluded that with regard to resolution and stability, the system out-performs current systems and is superior in terms of potential test costs, sample handling and sample transport. Reprod Nutr Dev, 1990, Suppl 2, 161s - 162s {Degradability in small bags of nitrogenous components of feed concentrates: standardization of the method and intra- and interlaboratory variability}; Verite R et al.; In sacco degradability of feed protein (DT) was measured in 13 feedstuffs by 4 laboratories according the French standardized procedure . Adjustment for variations in microbial activity by reference to DM disappearance of a standard sample of lucerne decreased within and between lab variability . When the standardized procedure was carefully followed, results were in rather good agreement between labs. Adv Appl Microbiol, 1990, 35, 171 - 94 Microbial levan; Han YW; Levans are natural polymers of the sugar fructose found in many plants and microbial products . Like dextrans, they are formed as an undesirable by-product of sugar juice processing . On the other hand, levans, which can only be produced from sucrose, have potential industrial applications as thickeners and encapsulating agents and could provide additional, valuable products from sugarcane juice . A strain of B . polymyxa (NRRL B-18475) produced a high yield of polysaccharide when grown on sucrose solution . Hydrolysis and subsequent analyses showed the product to consist entirely of D-fructose . 13C-NMR and methylation analyses indicated the products to be a beta(2----6)-linked polymer of fructose, with 12% branching . The polysaccharide has a Mr of approximately 2 million and is readily soluble in water . Levan has not been utilized, but if developed, could be useful in food and other industrial applications. Prev Assist Dent, 1990 Jan-Feb, 16(1), 7 - 10 {Disinfection of toothbrushes . Experimental research}; Fratto G et al.; Aim of the present paper is to verify in a vitro study, the possible disinfection of the toothbrushes with an UV instrument (Dentec 4000) . The modifications in microbic concentration after a contamination with microbial suspension of oral cavity have been estimated. Biol Met, 1990, 2(4), 191 - 6 Roles of trace metals in transcriptional control of microbial secondary metabolism; Weinberg ED; Secondary metabolism in bacteria and fungi requires a much narrower range of environmental concentrations of key trace metals than that permitted for primary metabolism . The cells acquire appropriate quantities of the key metals at the initiation of the shift from primary to secondary metabolism . Evidence suggests that these essential micronutrients participate in regulating the expression of genes responsible for synthesis of secondary metabolites and/or morphological alterations associated with cellular differentiation. Cornea, 1990, 9 Suppl 1, S25 - 7; discussion S31-2 Is daily wear better than extended wear? Arguments in favor of daily wear; Weissman BA et al.; The use of contact lenses for extended wear appears to be accompanied by an increase in several complications, the most serious of which is corneal infection . It has been proposed that infection is due to corneal epithelial layer microtrauma and lens care system contamination, but noncompliance, contamination of care systems, and microtrauma {especially among keratoconics and polymethylmethacrylate (PMMA) lens users, for example} are so common in daily wear that we believe they are insufficient to explain the approximately sixfold increase in the rate of corneal infection with extended wear . Perhaps the chronic hypoxic stress of extended wear use of contact lenses substantially reduces the resistance of the epithelium to either injury or microbial infection . Until evidence is provided that new contact lenses have sufficient oxygen transmissibility (Dk/L) to fully satisfy corneal oxygen needs under extended wear conditions, and the extended wear use of such lenses is thoroughly tested in a study population, we believe that the majority of contact lens patients should be maintained on daily wear schedules. Annu Rev Pharmacol Toxicol, 1990, 30, 369 - 85 Mutational spectrometry in animal toxicity testing; Thilly WG; The microbial geneticists who pioneered the study of mutational spectra have shown us how rich a source of mutagen-specific information it can be for the pharmacologist and toxicologist . Contributions by physical chemists and molecular biologists have led to a practical means to observe mutation spectra directly from the DNA of cultured human cells and this review suggests that the same methodology may be applied successfully to the study of mutations and mutational spectra in tissues of experimental animals and humans . In toxicological testing, the new field of mutational spectrometry offers a previously unattainable level of sensitivity and specificity as well as new tools for dissecting mechanisms of pharmacologic and toxic action. Klin Khir, 1990, (1), 1 - 3 {Prevention of microbial contamination of surgical wounds}; Buianov VM et al.; Comparative analysis of 3707 operations on the organs of the abdominal cavity has shown the significant advantage of the suggested by the authors method for intraoperative wound protection with latex rubber in combination with placing the longitudinal removable sutures over the subcutis and skin, and dressing-free management of the wounds in prophylaxis of the postoperative purulent wound complications . After 310 operations of different contamination degree performed with the use of the given method, no suppuration of the operative wounds was noted. Artery, 1990, 17(3), 170 - 5 Influence of acarbose (a glucosidase inhibitor) on experimental atherosclerosis in the rabbit; Kritchevsky D et al.; Acarbose, a complex oligosaccharide of microbial origin, was added at levels of 100, 200 or 400 mg/kg to an atherogenic diet fed to New Zealand White rabbits . The rabbits consumed 75 g/day of each diet, thus the daily intake of Acarbose was 7.5, 15 and 30 mg . Rabbits fed 30 mg/day of Acarbose showed reduced levels of plasma cholesterol, intermediate density lipoprotein (IDL) and low density lipoprotein (LDL) . Aortic sudanophilia was inhibited by 23% in rabbits fed 7.5 mg/day of Acarbose and by 43% in rabbits fed 15 or 30 mg/day . Acarbose had been shown previously to lower serum cholesterol and triglyceride levels in rats and mice . Our studies demonstrate that it also inhibits atherogenesis in rabbits fed 0.2% cholesterol. Arch Microbiol, 1990, 153(4), 329 - 36 Soluble and membrane-bound ferrisiderophore reductases of Escherichia coli K-12; Fischer E et al.; After uptake of microbial ferrisiderophores, iron is assumed to be released by reduction . Two ferrisiderophore-reductase activities were identified in Escherichia coli K-12 . They differed in cellular location, susceptibility to amytal, and competition between oxygen and ferrichrome-iron(III) reduction . The ferrisiderophore reductase associated with the 40,000 X g sediment (membrane-bound enzyme) was inhibited by 10 mM amytal in contrast to the ferrisiderophore reductase present in the 100,000 X g supernatant (soluble enzyme) . Reduction by the membrane-bound enzyme followed sigmoid kinetics, but was biphasic in the case of the soluble enzyme . The soluble reductase could be assigned to a protein consisting of a single polypeptide of Mr 26,000 . Reduction of iron(III) by the purified enzyme depended on the addition of NADH or NADPH which were equally active reductants . The cofactor FMN and to a lesser degree FAD stimulated the reaction . Substrate specificity of the soluble reductase was low . In addition to the hydroxamate siderophores arthrobactin, schizokinen, fusigen, aerobactin, ferrichrome, ferrioxamine B, coprogen, and ferrichrome A, the iron(III) complexes of synthetic catecholates, dihydroxy benzoic acid, and dicitrate, as well as carrier-free iron(III) were accepted as substrates . Both ferrisiderophore reductases were not controlled by the fur regulatory system and were not suppressed by anaerobic growth. Eicosanoids, 1990, 3(1), 1 - 22 The neutrophil and leukotrienes--role in health and disease; Konig W et al.; The granulocyte plays a major role in inflammatory processes by its capability to produce and release proinflammatory mediators such as the leukotrienes . This class of mediators exerts multiple functions in various physiological and pathophysiological processes . The interdependent interaction among the various mediator cascades, the inflammatory cells as well as the neuroendocrine system are areas of current interest . Appropriate stimuli (immunological, non immunological) by their defined pattern of signal transduction are responsible for priming, cellular activation and deactivation of granulocytes as it is shown for microbial infection . Thus the mediators may provide the prerequisites for a balanced homeostasis during host defense . It is clear that among the complexity of mediators not a single factor but the interaction of multiple mediator cascades reflect the final outcome of the disease process . In this regard the actual concentrations at local sites are obviously more relevant as those in whole body fluids. Adv Exp Med Biol, 1990, 256, 101 - 19 Structure-activity relationship of chemically synthesized nonreducing parts of lipid A analogs; Homma JY et al.; Some synthetic compounds of the nonreducing part of lipid A were found to preserve significant immunopharmacological activities of the endotoxin, at the same time showing very slight if any endotoxic activity such as pyrogenicity lethality or Shwartzman reactivity . Thus, divers activities of the endotoxin which had earlier been considered intrinsic and inseparable were shown to be separable when certain synthetic analogs of lipid A-subunit are at work . The combination of acyl components as well as phosphorylation and acylation positions in these partial structure analogs of lipid A affect the expression of biological activities of the endotoxin . Moreover, stereospecificities of acyl substituents contribute differently to enhance the various biological activities of the endotoxin . It was remarkable that protective activities of the endotoxin such as enhancing nonspecific resistance against microbial infections and antitumor activity are preserved in lipid A-subunit analogs of small molecular weight of ca . 1,000, which at the same time lose all or most toxic activity such as pyrogenicity, lethality and Shwartzman reactivity . It is hoped that new derivatives of lipid A and/or lipid A-subunit which exert only limited biological activities of endotoxin, whether they be protective or toxic, can be synthesized in order to clarify the structural requirements for expressing a given activity . Such compounds will be useful not only for promoting basic endotoxin research but also for application in clinical medicine . Further detailed experiments on the structure-activity relationships of the newly synthesized 4-O-phosphono-D-glucosamine derivatives binding acyl substituents of varying carbon chain length at the 2-N- and 3-O- positions are in progress. Biosens Bioelectron, 1990, 5(1), 13 - 26 Piezoelectric crystal biosensors; Ngeh-Ngwainbi J et al.; The recent development of piezoelectric devices as biosensors is reviewed . Biological materials, like enzymes, lipids, antibodies and antigens, have been used as specific coatings and were utilized for the determination of different substrates . Methods of protein coating and several applications are reported including microgravimetric immunoassays, microbial assays, DNA hybridization, enzyme detections and gas phase biosensors . Although the piezoelectric immunochemical sensor is convenient to use and very promising, a thorough understanding of the different phenomena associated with crystals frequency measurement in biological reactions is still lacking and deserves further investigation. Microbios, 1990, 63(256-257), 165 - 71 Detection of microbial trypsin-like enzymes by use of an agar gel; Pederson ED et al.; Certain oral micro-organisms associated with periodontal diseases elaborate trypsin-like enzymes . This study describes a single assay for these enzymes, based on the incorporation of the synthetic substrate N-alpha-benzoyl-DL-arginine-p-nitroanilide (BAPNA) into ion-agar gel . The system can provide quantitative or qualitative data within 24 h and is suitable for use in the dental clinic. J Basic Microbiol, 1990, 30(3), 209 - 24 Microbial DNA topoisomerases and their inhibition by antibiotics; Zimmer C et al.; Supercoiling of bacterial DNA is regulated by topoisomerases and influences most of the metabolic processes involving DNA . The present review is devoted to a brief outline of the supercoiled state