Crit Care Nurs Clin North Am, 1994 Jun, 6(2), 405 - 19 Neonatal sepsis: confronting the challenge; Witek-Janusek L et al.; The challenge of neonatal sepsis is reviewed and updated, and the incidence and importance of microbial pathogens are addressed . Important maternal, neonatal, and environmental risk factors responsible for increasing the incidence of neonatal sepsis are reviewed . Underlying the neonate's susceptibility to sepsis is the markedly limited immunologic defense of the neonate . The neonate's humoral, cellular, and barrier defense limitations are analyzed with respect to how each alters host susceptibility . The clinical manifestations and progression of sepsis in the neonate are reviewed and the status of new therapeutic approaches is examined . Ways that nurses can assist in the prevention and limitation of disability from neonatal sepsis are provided. Quintessence Int, 1994 Jun, 25(6), 435 - 9 Atmospheric contamination during dental procedures; Legnani P et al.; The aim of this study was to evaluate the level of aerosol pollution following dental procedures performed in 15 sessions with an ultrasound scaler and a bicarbonate cleaner . The air contamination was measured by means of the Surface Air System method and the "plate" method (Air Microbial Index) . Each colony-forming unit per cubic meter of air was allotted a unit value for statistical analysis . The data were then compared with the hygienic assessments made in previous studies . The results showed that the initial environmental conditions in a dental office initiated at the level of mediocre, then became very bad during dental procedures, and fell between mediocre and very bad at the end of the procedures. Oncol Nurs Forum, 1994 Jun, 21(5), 857 - 65; quiz 866-7 Bacterial translocation: nursing implications in the care of patients with neutropenia; Carter LW; PURPOSE/OBJECTIVES: To describe bacterial translocation; the potential causes and influencing factors of bacterial translocation; the anatomy, physiology, and immunology of the small intestine; and the significance of bacterial translocation in patients with cancer . DATA SOURCES: Published articles and books, as well as clinical experience . DATA SYNTHESIS: 50% of infections in patients with cancer who are neutropenic result from endogenous sources such as the normal microbial flora of the bowel . This process called bacterial translocation may be responsible for symptoms such as fever of unknown origin in these patients . CONCLUSION: Maintaining normal bacterial ecology and mucosal integrity of the bowel can reduce the risk of bacterial translocation . IMPLICATIONS FOR NURSING PRACTICE: Care is directed at preventing constipation and maintaining integrity of the normal bowel and microbial flora by providing a low-microbial diet that contains adequate fluid and fiber and by encouraging good oral care. Microbiol Res, 1994 Jun, 149(2), 167 - 71 Effect of soil treatment with the organophosphorus insecticide Profenfos on the fungal flora and some microbial activities; Abdel-Mallek AY et al.; Tests were conducted to determine the effects of Profenfos {(0-(4-bromo-2-chlorophenyl) 0-ethyl S-n-propyl-phosphorothioat} on fungal populations and some activities in soil . Profenfos (at 5.4 micrograms active ingredient/g dry soil), has a significant adverse effect on the count of total fungi after 2, 4 and 6 weeks after treatment . This effect was completely alleviated after longer incubation . Incorporation of this insecticide into the agar medium inhibited the total count of soil fungi at 6.4 and 38.4 micrograms ml-1 . Initial activation followed by a decrease in CO2 output occurred in soil treated with 5.4 micrograms a.i./g . The two doses of Profenfos accelerated urease activity for 6 weeks after soil treatment, but inhibited the enzyme activity after longer periods . An inhibitory effect on nitrate reductase activity was observed with some insecticide treatments in the early stages of incubation followed by an activation in certain cases. Diagn Microbiol Infect Dis, 1994 Jun, 19(2), 81 - 8 Mycobacterial identification by computer-aided gas-liquid chromatography; Smid I et al.; The suitability of the Microbial Identification System (MIS) marketed by Microbial ID (Newark, DE, USA) for routine diagnosis of clinically important mycobacteria was investigated and assessed . Cellular fatty acids were extracted from 1077 stock and recent clinical isolates . They were analyzed using a gas-liquid chromatograph combined with MIS software . The MIS system finally identifies the isolates by comparing their fatty-acid compositions with a standard library for mycobacteria . As the library search usually results in more than one possible match, suitable identification criteria were determined . The stricter these criteria are, the more the percentage of false-positive identifications can be reduced, but at the cost of more cases that remain undecided and require additional analysis . Under conditions similarity index (SI) SI1 > or = 0.4 and SI1-SI2 > or = 0.1, 63% of all isolates were correctly and 6% incorrectly identified. Afr J Med Med Sci, 1994 Jun, 23(2), 171 - 6 Immunoglobulin and immune complex levels in Nigerians with acute lymphoblastic leukaemia; Okpala IE et al.; Twenty-five patients with acute lymphoblastic leukaemia (ALL) aged 10 months to 43 years and twenty-five age and sex matched healthy control subjects were investigated in this study . Serum immunoglobulins A, G and M levels were measured by single radial immunodiffusion method and immune complex levels estimated by polyethylene glycol precipitation technique . Significant increase in immune complexes and decrease in immunoglobulin G were observed in the patients . Although not statistically significant, the patients had a lower mean level of immunoglobulin A, and a higher mean immunoglobulin M concentration than the controls . Hypoimmunoglubulinaemia observed in this study may contribute to the aetiology of ALL or be an effect of the disease . Raised immune complexes could result from specific antibodies combining with tumour associated or microbial antigens . Immunoglobulin G levels showed a significant positive correlation with survival in the patients . The adverse effect of reduced immunoglobulin G on the prognosis of ALL is probably due to compromised immunity in the patients. Ther Immunol, 1994 Jun, 1(3), 187 - 96 Interleukin-12: a cytokine with therapeutic potential in oncology and infectious diseases; Gately MK et al.; IL-12 is a cytokine that promotes cell-mediated immunity by promoting Th1-type cytokine responses, enhancing the lytic activity of NK/LAK cells, augmenting specific CTL responses, and inducing the production of IFN-gamma . On the other hand, IL-12 suppresses the development of Th2-type cytokine responses and humoral immunity, particularly IgGl and IgE responses . It is likely that IL-12 normally plays an important role in the host defense against intracellular microbial pathogens . In addition, the administration of rIL-12 to mice has been shown to have potent therapeutic effects in several tumour and infectious disease models . IL-12 has been shown to be more efficacious than IL-2 in several murine tumour models, and toxicology studies suggest that it may have a substantially better therapeutic index . In addition, the long serum half-life of IL-12 relative to other cytokines will allow more flexibility in dosing schedules . However, future clinical trials are required to determine whether the efficacy of IL-12 seen in these experimental models is predictive for its use as an immunomodulatory drug in humans. Ann N Y Acad Sci, 1994 May 28, 725, 128 - 45 Interactions between respiratory epithelial cells and cytokines: relationships to lung inflammation; Adler KB et al.; Epithelial cells lining respiratory airways can participate in inflammation in a number of ways . They can act as target cells, responding to exposure to a variety of inflammatory mediators and cytokines by altering one or several of their functions, such as mucin secretion, ion transport, or ciliary beating . Aberrations in any of these functions can affect local inflammatory responses and compromise pulmonary defense . For example, oxidant stress can increase secretion of mucin and depress ciliary beating efficiency, thereby affecting the ability of the mucociliary system to clear potentially pathogenic microbial agents . Recent studies have indicated that airway epithelial cells also can act as "effector" cells, synthesizing and releasing cytokines, lipid mediators, and reactive oxygen species in response to a number of pathologically relevant stimuli, thereby contributing to inflammation . Many of these epithelial-derived substances can act locally, affecting both neighboring cells and tissues, or, via autocrine or paracrine mechanisms, affect structure and function of the epithelial cells themselves . Studies in our laboratories utilized cell cultures of both human and guinea pig tracheobronchial and nasal epithelial cells, and isolated human nasal epithelial cells, to investigate activity of respiratory epithelial cells in vitro as sources of cytokines and inflammatory mediators . Primary cultures of guinea pig and human tracheobronchial and nasal epithelial cells synthesize and secrete low levels of IL-6 and IL-8 constitutively . Production and release of these cytokines increases substantially after exposure to specific inflammatory stimuli, such as TNF or IL-1, and after viral infection. Transplantation, 1994 May 27, 57(10), 1462 - 5 Screening donors for xenotransplantation . The potential for xenozoonoses; Michaels MG et al.; Xenotransplantation is a potential solution to the current donor shortage for solid organ transplantation . The transmission of infectious agents from donor organs or bone marrow to the recipient is a well-recognized phenomenon following allotransplantation . Thus the prospect of xenotransplantation raises the issue of xenozoonoses--i.e., the transmission of animal infections to the human host . Anticipating an increasing number of baboon to human transplants, 31 adult male baboons (Papio cynocephalus) from a single colony in the United States were screened for the presence of antibody to microbial agents (principally viral) that may pose a significant risk of infection . Antibody to simian cytomegalovirus, simian agent 8 and Epstein-Barr virus, was found in 97% of animals tested . Antibody to simian retroviruses and Toxoplasma gondii was found in 30% and 32% respectively . Discordant results were found when paired samples were examined by two primate laboratories . This was particularly noted when methodologies were based on cross-reaction with human viral antigens . These results highlight the need to develop specific antibody tests against the species used for xenotransplantation. J Mol Biol, 1994 May 20, 238(5), 709 - 32 Horse pancreatic lipase . The crystal structure refined at 2.3 A resolution; Bourne Y et al.; Pancreatic lipase (EC 3.1.1.3) plays a key role in dietary fat digestion by converting triacylglycerols into 2-monoacylglycerols and free fatty acids in the intestine . Although the crystallographic structures of the human pancreatic lipase and of a human lipase-porcine colipase complex have been solved, no refined structure of pancreatic lipase has yet been published . The crystal structure of the horse enzyme was solved by the molecular replacement method from the model of the human pancreatic lipase and subsequently refined to 2.3 A resolution . The final model contains two molecules of 449 amino acid residues each in the asymmetric unit, 705 well-defined water molecules and two calcium ions . The two molecules in the asymmetric unit of the orthorhombic crystals are related by a 2-fold non-crystallographic symmetry axis as in the case of the human lipase . However, the association between the two molecules in their respective crystal forms is different . The overall molecular structure of the horse lipase is very similar to that of the human enzyme . The horse lipase is made up of two well-defined domains . The N-terminal domain which bears the active centre has a typical alpha/beta hydrolase fold topology . The C-terminal domain which is devoted to colipase binding has a beta-sheet sandwich topology . Comparison of equivalent C alpha atom positions between the final model of the horse lipase and the human lipase structure shows only slight differences which are mainly located in the C-terminal domain . The horse enzyme possesses the common features of the known mammalian and microbial lipases, in particular the "flap" covering the catalytic triad . In addition to more precise information concerning these features, the elucidation of the horse lipase crystal structure allowed us to better understand the structural basis of the kinetic behaviour of pancreatic lipases towards a soluble substrate, p-nitrophenyl acetate, and the different sensitivity of these enzymes towards limited proteolysis. Br J Hosp Med, 1994 May 18-31, 51(10), 538 - 41 Contact lens wear by hospital health care staff: is there cause for concern? Hay J, Seal DV. The increasing use of contact lenses means that some hospital staff wear them at work . Yet hospitals inevitably contain populations of pathogens . This article reviews the risks of microbial keratitis faced by contact lens wearers, and suggests ways to avoid them. Cancer Res, 1994 May 15, 54(10), 2719 - 23 Intratumoral generation of 5-fluorouracil mediated by an antibody-cytosine deaminase conjugate in combination with 5-fluorocytosine; Wallace PM et al.; Cytosine deaminase (CD) is a microbial enzyme that can convert the antifungal agent 5-fluorocytosine (5-FC) into the antitumor agent, 5-fluorouracil (5-FU) . The enzyme was chemically conjugated to the L6 monoclonal antibody, forming a conjugate that bound to antigens on the H2981 lung adenocarcinoma . Detailed studies were undertaken to determine the extent to which L6-CD generated 5-FU in tumor-bearing mice . Very high tumor:blood ratios of L6-CD (42:1) in vivo were obtained by injecting the conjugate followed 24 h later by an antiidiotypic antibody that could bind to circulating L6-CD but not to L6-CD that was bound to H2981 cells . As a result, significantly more 5-FC could be administered (> 800 mg/kg) than 5-FU (90 mg/kg) . L6-CD converted 5-FC into 5-FU such that the L6-CD/antiidiotypic monoclonal antibody/5-FC combination resulted in 17 times more intratumoral 5-FU compared to systemic 5-FU administration . The conversion was antigen dependent since much lower intratumoral 5-FU levels were obtained in H3719 tumors that failed to localize L6-CD . The conversion of 5-FC into 5-FU was low in blood, kidneys, and liver . This demonstrates that a major increase in intratumoral drug concentrations can be attained with an monoclonal antibody-enzyme conjugate in combination with an anticancer prodrug compared to systemic drug therapy. Anal Biochem, 1994 May 15, 219(1), 53 - 60 Fluorescent spot test method for specific detection of beta-lactamases; Chen KC et al.; A simple, sensitive fluorescent spot test method for specific detection of microbial beta-lactamases has been developed, based on the modification of a previously disclosed method (K . C . S . Chen, October 23, 1990, U.S . Patent 4,965,193) . The new fluorescence developer used in the present study consisted of 0.5 mM HgCl2, in 0.5 M sodium citrate buffer, pH 4.5, prepared in 0.5% formaldehyde aqueous solution . A beta-lactam substrate solution consisting of a beta-lactam antibiotic with an acyl side chain containing an alpha-amino group and an alpha-phenyl group, or its derivatives, was incubated with a beta-lactamase-producing organism . One volume of the fluorescence developer was added to 4 vol of the incubated beta-lactam substrate solution, followed by heating the mixture at 45 degrees C for 10 min . The mixture was spotted on filter paper . Production of fluorophore indicated beta-lactamase activity . Each fluorophore was analyzed by TLC and its chemical identity was determined . Using ampicillin as the penicillinase substrate and cephalexin as the cephalosporinase substrate, the new method can be conveniently carried out by using dropping bottles for storing and dispensing the substrate solutions and the fluorescence developer . This modified method also provided more favorable conditions for the penicillinases to remain active during fluorescence development . Therefore, the sensitivity of the test was increased. J Biotechnol, 1994 May 15, 34(2), 185 - 93 Rapid and quantitative analysis of recombinant protein expression using pyrolysis mass spectrometry and artificial neural networks: application to mammalian cytochrome b5 in Escherichia coli; Goodacre R et al.; Recombinant Escherichia coli clones encoding between 0 and 6 copies of the mammalian cytochrome b5 gene were subjected to pyrolysis mass spectrometry (PyMS) . To deconvolute the pyrolysis mass spectra so as to obtain quantitative information on the amount of cytochrome b5 produced fully-interconnected feedforward artificial neural networks (ANNs) were studied . It was found that the combination of PyMS and ANNs could be used to predict the amount of cytochrome b5 expressed in E . coli . PyMS is a novel, convenient and rapid method for the screening and analysis of microbial and other cultures producing recombinant proteins. Carbohydr Res, 1994 May 5, 257(2), 227 - 38 Configurational stability and molecular dynamics of acetal-linked pyruvate substituents in polysaccharides; Miertus S et al.; Pyruvate groups occur naturally in many microbial polysaccharides as nonsaccharidic components and significantly affect their physicochemical and biological properties . The configuration of the acetal carbon of pyruvate groups is mainly influenced by the favoured equatorial orientation of the methyl group . Evaluation of conformational energies has been carried out to assess the relative stabilities of the R and S isomers as a function of configuration and torsional angles for several residue models, including methyl 4,6-O-(1-carboxyethylidene)-alpha-D-galactopyranoside (1) . Different levels of theoretical approach are used ranging from ab initio, semiempirical (AM1), and molecular mechanics (MM) methods up to molecular dynamics (MD) . The higher stability of the isomer R of 1 was demonstrated by all of the methods used, thus giving full agreement with the NMR data on the natural compounds. Math Biosci, 1994 May, 121(1), 61 - 110 Periodic, quasi-periodic, and chaotic coexistence of two competing microbial populations in a periodically operated chemostat; Lenas P et al.; It is well known that when two microbial populations competing for a single rate-limiting nutrient are grown in a chemostat with time-invariant inputs, with competition being the only interaction between them, they cannot coexist, but eventually one of the two populations prevails and the other becomes extinct . It has been suggested that periodic variation of one of the chemostat's operating parameters can stabilize the coexistence state of the two microbial populations . A systematic numerical study of the model equations describing microbial competition in a chemostat with periodically varying dilution rate is performed, and it is shown that coexistence of the competing microbial populations is obtained for a wide range of operating conditions . The coexistence state is usually in the form of limit cycle oscillations . However, cases of chaotic behavior resulting from successive period doublings and quasi-periodicity are also observed. J Environ Sci Health B, 1994 May, 29(3), 485 - 506 The effect of multiple soil applications of disulfoton on enhanced microbial degradation in soil and subsequent uptake of insecticidal chemicals by potato plants; Chapman RA et al.; Potatoes were grown during 1992 in 2 m2 plots of loam which had received 1, 2 or 3 annual treatments of Di-Syston 15G, equivalent to 3.36 kg AI/ha, in furrow at planting . The presence of enhanced degradative activity to the sulfoxide and sulfone metabolites of disulfoton in the soil treated in the previous two years was confirmed by laboratory tests prior to the 1992 treatments . Soil, seed potato and foliage from the three treatments were analyzed for disulfoton and its sulfoxide and sulfone metabolites for 12 wk following planting/treatment . Disulfoton was the major insecticidal component of the soil, a minor component of the seed piece and was not detected (< 0.02 ppm) in potato foliage . Disulfoton concentrations in each of the three substrates sampled were similar for the three treatments . Disulfoton sulfoxide and sulfone were the major insecticidal components of the seed piece and foliage . Their maximum concentrations in 1st year soil, seed pieces and foliage were ca . 2x, 2x and 6x, respectively, those measured in the 2nd and 3rd year treatments . The results demonstrate that enhanced microbial degradation of relatively minor insecticidal compounds in the soil can profoundly affect insecticide levels in the plant when these compounds are the major insecticidal components accumulated . The broader implications for crop protection using soil-applied systemic insecticides are discussed. Gut, 1994 May, 35(5), 669 - 74 Increased macrophage subset in inflammatory bowel disease: apparent recruitment from peripheral blood monocytes; Rugtveit J et al.; Mucosal specimens from active Crohn's disease (ileum, n = 6; colon, n = 6), active ulcerative colitis (n = 9), normal ileum (n = 6), and normal colon (n = 6) were subjected to paired immunofluorescence staining for characterisation of macrophage subsets in situ . In the normal state, only few CD68+ macrophages (< 10%) expressing the myelomonocytic L1 antigen (calprotectin) were seen . In inflamed mucosa, especially near small vessels, the CD68+L1+ fraction increased with the degree of inflammation, near ulcers to median 65% (range 35-91%) . Cells reactive with the monoclonal antibody RFD7 were also increased in inflammation but less than 5% of them costained for L1 antigen . It is concluded that L1 producing macrophages are distinct from the RFD7+ subset and probably recently recruited from peripheral blood monocytes . Like granulocytes, L1+ macrophages may be important in non-specific defence, providing calprotectin with putative anti-microbial and anti-proliferative properties. Br J Rheumatol, 1994 May, 33(5), 413 - 9 Bacterial superantigens in autoimmune arthritis; Goodacre JA et al.; Discoveries of the biological properties of bacterial superantigens have given rise to much speculation about their possible role in the pathogenesis of autoimmune diseases . There is an increasing body of data to support these speculations . This field of research has the potential to provide a long-elusive understanding of the mechanisms which underlie microbial involvement in the pathogenesis of autoimmune polyarthritides. Diabetes, 1994 May, 43(5), 613 - 21 Immunoregulatory and cytokine imbalances in the pathogenesis of IDDM . Therapeutic intervention by immunostimulation? Rabinovitch A. The autoimmune response that leads to destruction of pancreatic islet beta-cells and insulin-dependent diabetes mellitus (IDDM) has a genetic basis; however, environmental factors can exert profound modulating effects on the genetic predisposition to this autoimmune response . Recent studies in animal models for human IDDM, the genetically diabetes-prone NOD mouse and BB rat, have revealed that microbial agents--including certain viruses and extracts of bacteria, fungi, and mycobacteria--often have a protective action against diabetes development . Many of these microbial preparations are immune adjuvants, which are agents that stimulate the immune system . The protective effects of these agents against diabetes appear to involve perturbations in the production of cytokines, which are polypeptides produced by and acting on cells of the immune system . Thus, recent studies in NOD mice suggest that the islet beta-cell-directed autoimmune response may be mediated by a T-helper 1 (Th1) subset of T-cells producing the cytokines interleukin-2 (IL-2) and interferon-gamma . These studies also suggest that the diabetes-protective effects of administering microbial agents, adjuvants, and a beta-cell autoantigen (GAD65 {glutamic acid decarboxylase}) may result from activation of a Th2 subset of T-cells that produce the cytokines IL-4 and IL-10 and consequently downregulate the Th1-cell-mediated autoimmune response . The clinical implication of these findings is that the autoimmune response leading to islet beta-cell destruction and IDDM may be amenable to prevention or suppression by therapeutic interventions aimed at stimulating the host's own immunoregulatory mechanisms. Cancer Res, 1994 May 1, 54(9), 2419 - 23 Wortmannin, a potent and selective inhibitor of phosphatidylinositol-3-kinase; Powis G et al.; Phosphatidylinositol-3-kinase is an important enzyme for intracellular signaling . The microbial product wortmannin and some of its analogues have been shown to be potent inhibitors of phosphatidylinositol-3-kinase . The 50% inhibitory concentration for inhibition by wortmannin is 2 to 4 nM . Kinetic analysis demonstrates that wortmannin is a noncompetitive, irreversible inhibitor of phosphatidylinositol-3-kinase, with inactivation being both time- and concentration-dependent . Wortmannin has previously been reported to be an inhibitor of myosin light chain kinase but with an inhibitory concentration of 0.2 microM . Wortmannin was found not to be an inhibitor of phosphatidylinositol-4-kinase, protein kinase C, or protein tyrosine kinase . Wortmannin inhibited the formation of phosphatidylinositol-3-phosphates in intact cells . The results of the study suggest that wortmannin and its analogues may have utility as pharmacological probes for studying the actions of phosphatidylinositol-3-kinase. J Immunol, 1994 May 1, 152(9), 4699 - 705 A single amino acid substitution in core residues of S-antigen prevents experimental autoimmune uveitis; Singh DP et al.; We have previously reported that microbial Ags, having a three- to six-amino-acid-sequence homology with a uveitopathogenic epitope (peptide M) of retinal soluble protein (S-Ag), induce experimental autoimmune uveitis (EAU) . Another uveitopathogenic epitope (peptide G) of S-Ag also was characterized . In addition, we have characterized the core sequences by truncating peptides G and M from amino acid and carboxyl termini . In this study, we have further defined the core sequences using synthetic octapeptides with a single amino acid substitution . In addition, the analogues of peptides Gm5 or Mm4 are capable of inhibiting the proliferative response of T-lymphocytes from rats immunized with peptides G-8 or M-8, respectively . Co-injection of a pathogenic peptide with nonpathogenic substitution analogues blocked the induction of EAU . These results suggest that specific nonpathogenic analogues with single amino acid substitution derived from pathogenic peptides have potential for prevention and therapy of autoimmune diseases. J Infect, 1994 May, 28(3), 293 - 304 Microbial contamination of cases used for storing contact lenses; Clark BJ et al.; A survey of the hygienic practices of 178 contact lens wearers in west central Scotland was conducted along with assessment of microbial contamination of their lens storage cases . Multivariate analysis indicated that in some subgroups of lens wearers, the method of disinfection used, the use of unmodified tap water and the age of the lens, were significantly associated with microbial contamination of storage cases . In addition, statistical analysis suggested that features other than those commonly considered as important in contact lens hygiene, and therefore included in this study, may be more significant predictors of contamination of cases . Instruction of patients, patient compliance and simplicity of the regimen for the care of contact lenses may be important for achieving their safer use. J Nat Prod, 1994 May, 57(5), 557 - 73 Genetically engineered synthesis of natural products; Scott AI; The feasibility of multi-step, one-flask total synthesis of natural products is demonstrated by cloning and overexpression of the corresponding biosynthetic enzymes from plant and microbial sources . As many as eight or nine enzymes can be recombined in vitro to reach an advanced intermediate in the vitamin B12 pathway. Pediatr Dent, 1994 May-Jun, 16(3), 217 - 23 Disturbances in the oral cavity in pediatric long-term survivors after different forms of antineoplastic therapy; Nasman M et al.; Oral health and disturbances in dental development were studied in long-term survivors after antineoplastic therapy . Fifty-seven children treated with combination chemotherapy and 19 children treated with total body irradiation (TBI) prior to bone marrow transplantation (BMT) were examined . The variables studied were dental caries, salivary flow, salivary microbial counts, enamel disturbances, and disturbances in dental development . The results showed no increased caries experience in children treated with BMT or chemotherapy compared with controls . Children treated with BMT had a significantly lower salivary secretion rate of 0.7 +/- 0.4 ml/min, compared with 1.1 +/- 0.5 in the chemotherapy group, and 1.3 +/- 0.6 in the control group (P < 0.05) . The clinical examination showed equal numbers of teeth affected by disturbances in enamel mineralization in the BMT and chemotherapy groups . A mean 15.9 +/- 8.2 teeth were affected by disturbances in root development in the BMT group compared with 1.2 +/- 1.6 in the chemotherapy group (P < 0.001) . The results show that children who are long-term survivors of pediatric malignant diseases exhibit a wide range of disturbances in the oral cavity . In this study the most severe disturbances are found in children treated with total body irradiation prior to BMT. J Anim Sci, 1994 May, 72(5), 1344 - 54 In vitro determination of ruminal protein degradability using {15N}ammonia to correct for microbial nitrogen uptake; Hristov A et al.; An in vitro procedure was developed to estimate rate and extent of ruminal protein degradation using {15N}H3 to quantify uptake of protein degradation products for microbial protein synthesis . Incubations were conducted for 6 h in stirrer flasks with ruminal inoculum plus buffer, reducing solution, pectin, soluble carbohydrates, and added (15NH4)2SO4 . Seven protein concentrates were tested in the system . Samples of media were analyzed for 15N enrichment of NH3, microbial N, and total solids N . Degradation rate was computed from net (i.e., protein-added minus blank) release of NH3 N plus net synthesis of microbial protein N; escape was estimated assuming ruminal passage rate = .06/h . Over the course of the incubations, pH was stable at 6.6, protozoal numbers increased slightly, and microbial protein content increased by more than 200% . Free AA had not accumulated at the end of the incubations . Microbial protein synthesis was a linear function (P < .001; r2 = .780) of extent of degradation . Mean degradation rates and ruminal escapes determined were, respectively, .569/h and 10% (casein), .148/h and 29% (solvent soybean meal), .036/h and 63% (expeller soybean meal), .026/h and 70% (low solubles fish meal), .063/h and 49% (high solubles fish meal), .034/h and 64% (corn gluten meal), and .050/h and 55% (roasted soybeans) . Overall, degradation rates averaged 28% greater than those previously estimated using an inhibitor in vitro system; however, rates obtained for the fish meals using the 15N method were slower. Methods Find Exp Clin Pharmacol, 1994 May, 16(4), 271 - 8 Development of an azopolymer based colonic release capsule for delivering proteins/macromolecules; Cheng CL et al.; The colon, high in microbial contents with degradation ability of azo bonds, seems to be suitable for site-specific delivery of drugs . The degradation of azoaromatic hydrogel depends on the degree of swelling . However, the degree of swelling of azopolymers and the ability of the azoaromatic polymers to protect peptide drugs against the action of digestive enzymes still remains to be established . An azopolymer was synthesized and membranes were cast to investigate the degree of swelling . An azopolymer-coated capsule suitable for delivering peptides/proteins to the colon was developed by in vitro evaluation using vitamin B12 as a model drug to screen various formulations . For in vitro dissolution the half-changed method was used to mimic the pH-time profile in the GI tract . It was shown that the release of vitamin B12 is dependent on the degree of swelling which increases as pH increases . An in vivo study was also performed with insulin in azopolymer-coated capsules in 6 normal beagle dogs . The results suggest that this azopolymer-coated capsule is capable of protecting peptide/macromolecules against digestive enzymes . However, to obtain a promising peroral insulin capsule, more formulation work is required to achieve better absorption availability. J Periodontol, 1994 May, 65(5 Suppl), 539 - 44 Oral hygiene and compliance as risk factors in periodontitis; Bakdash B; Periodontitis is an inflammatory disease caused by microbial infection in the subgingival region . Risk factors associated with the development and progression of this disease are numerous, multifactorial, complex, and often not well defined across individuals and population groups . The focus of this paper is to provide an overview of existing information relevant to oral hygiene and compliance as risk factors in periodontitis and to present a 26-month prospective clinical study dealing with the same . The review of literature from epidemiological, clinical, and public health perspectives indicated that oral hygiene can be considered as risk indicator, risk factor, and/or risk predictor . The extent of oral hygiene contribution to the overall risk of individuals and population varies greatly across studies . Such variations may be attributed to population, personal and disease characteristics, research methodology used, and analytical strategies employed . The purpose of the study reported was to determine the role of self-reported daily oral hygiene practices and clinical plaque scores as risk factors in a middle-aged health-conscious population with early periodontitis . The group consisted of 174 subjects selected on the basis of putative bacterial risk markers and clinical indices . Medical, dental, behavioral, and clinical periodontal measurements including plaque, calculus, gingival inflammation, probing depth, bleeding on probing, and relative attachment level were obtained by one of two calibrated examiners at baseline, 14, 20, and 26 months . Data analyses revealed that some trends were seen relevant to self-reported oral hygiene and plaque scores favoring oral hygiene as a possible risk factor in periodontitis . Such trends, however, were neither clear nor consistent across various clinical parameters and observation intervals.(ABSTRACT TRUNCATED AT 250 WORDS) J Mol Evol, 1994 May, 38(5), 506 - 32 Nucleotide composition as a driving force in the evolution of retroviruses; Bronson EC et al.; All complete retrovirus sequences in the GenEMBL database were examined with the goal of assessing possible relationships between the nucleotide composition of retroviral genomes, the amino acid composition of retroviral proteins, and evolutionary strategies used by retroviruses . The results demonstrated that the genome of each viral lineage has a characteristic base composition and that the variations between groups are related to retroviral phylogeny . By analogy to microbial species, we suggest that the variations arise from group-specific patterns of directional mutations where the bias can be exerted on any of the four nucleotides . It is most likely that the mutational patterns are introduced during reverse transcription, and a direct participation of reverse transcriptase in the process is suspected . A straightforward strategy was used to analyze the compositional relationship between nucleotides and encoded amino acids . The procedure entailed calculations of amino acid frequencies from nucleotide content and the comparison of the calculated values to the observed amino acid frequencies in retroviruses . The results revealed an excellent correspondence between variation in genomic base composition and variation in amino acid composition of proteins with the compositional differences extending into all major coding regions of the viruses . Because of the magnitude and dispersion of these effects, and because of the nonconservative nature of many of the substitutions between groups with different genomic biases, we suggest that the variations in protein composition driven by biased nucleotide frequencies are an important factor in shaping the characteristic phenotypes of the different viral lineages . A clue to the nature of the evolutionary forces that are responsible for the generation of nucleotide biases was provided by the observation that viruses with radically different base frequencies most often inhabit the same cell type . This observation, along with analysis of amino acid and nucleotide replacement patterns between and within reverse transcriptase sequences from the various groups, permitted us to advance a model for the evolution of retroviruses . According to the model, speciation could initiate when daughter virions from a single progenitor vary in the direction of their mutational bias . These variations would exert a pleiotropic effect on the frequencies of nucleotides in all viral genes and consequently on the frequencies of amino acids in the encoded proteins . The variants with the most extreme compositional differences would have a selective advantage because their different precursor requirements would enable them to occupy different ecological niches within a single cell.(ABSTRACT TRUNCATED AT 400 WORDS) Microbiology, 1994 May, 140 ( Pt 5), 1085 - 96 Weak acid preservatives block the heat shock response and heat-shock-element-directed lacZ expression of low pH Saccharomyces cerevisiae cultures, an inhibitory action partially relieved by respiratory deficiency; Cheng L et al.; Inhibition of microbial growth by weak acid preservatives increases with medium acidification, since these agents enter cells in the undissociated state . Many of the effects of these acids are due to the cytoplasmic acidification they cause as they dissociate in the higher pH environment of the cytosol . Sorbic and benzoic acids, two widely used preservatives, were found to exert pronounced effects on the heat shock response and thermotolerance of Saccharomyces cerevisiae . These effects were strongly influenced by the pH of the culture medium . In low pH cultures sorbate inhibited the induction of thermotolerance by sublethal heat shock, causing strong induction of respiratory-deficient petites among the survivors of heat treatment . However, when the culture pH was above 5.5 sorbate acted as a powerful chemical inducer of thermotolerance in the absence of any sublethal heat treatment . Sorbate and benzoate also inhibited heat induction of the major heat shock proteins in low pH yeast cultures . This appears to result from lack of induction of the heat shock element (HSE) promoter sequence since sorbate prevented heat induction of a HSE-lacZ fusion at low pH . The uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP) and the plasma-membrane-ATPase inhibitor diethylstilboestrol were identified as additional inhibitors of heat induction of heat shock proteins . Numerous chemicals induce the heat shock response in the absence of heat stress, but sorbate, benzoate, CCCP and diethylstilboestrol are the first compounds shown to act as selective inhibitors of heat-induced protein expression in yeast . In the presence of sorbate concentrations which, at low pH, totally inhibit both the heat shock response and growth of cells competent in respiration, respiratory-deficient petites still retain a limited capacity for growth and for heat induction of heat shock proteins . This restoration of a response to heat shock in acidified sorbate-treated cultures of petites might contribute to their higher capacity for growth in the presence of sorbate. J AOAC Int, 1994 May-Jun, 77(3), 760 - 4 Simple and rapid determination of phytase activity; Engelen AJ et al.; A simple and rapid method is described for determining the enzymatic activity of microbial phytase . The method is based on the determination of inorganic orthophosphate released on hydrolysis of sodium phytate at pH 5.5. J Steroid Biochem Mol Biol, 1994 May, 49(1), 93 - 100 Microbial transformations of steroids--VIII . Transformation of progesterone by whole cells and microsomes of Aspergillus fumigatus; Smith KE et al.; The filamentous fungus, Aspergillus fumigatus, efficiently hydroxylated exogenous progesterone producing, after 3 h of incubation, 11 alpha- and 15 beta-hydroxyprogesterone as major products, 7 beta-hydroxyprogesterone as a minor product and trace amounts of 7 beta, 15 beta- and 11 alpha, 15 beta-dihydroxyprogesterone . After 72 h the dihydroxyprogesterones were the sole metabolites in the culture medium . Microsomes, prepared by Ca2+ precipitation, catalysed only monohydroxylation of progesterone at the same sites as whole cells . Hydroxylation was dependent on NADPH (but not NADH) which was replaceable by NaIO4 . Hydroxylation was inhibited by carbon monoxide and by the azole fungicide, ketoconazole . Microsomes gave a dithionite-reduced, carbon monoxide difference absorbance spectrum with a peak at 448 nm and a Type-I progesterone-binding spectrum typical of cytochrome P450 interaction with substrate . Ketoconazole inhibition studies suggest the presence of two non-inducible cytochrome P450 progesterone hydroxylases, one possessing 7 beta site-selectivity, the other 11 alpha/15 beta site-selectivity. J Chir (Paris), 1994 May, 131(5), 221 - 35 {Effects of ischemia and revascularization on the epithelium of the small intestine: study on swine}; Barthod F; Ischaemia of the small intestine leads to the destruction of the intestinal mucosa . The capacity of the epithelium to regenerate is proportional to the duration of revascularization . The aim of this work was to analyze the kinetic aspects of intestinal epithelial regeneration after destruction due to prolonged ischaemia . This study was conducted in 44 animals (swine) after development of an ischaemia-revascularization protocol of a jejunal loop and bipolar secondary cutaneous exteriorization . After a first series with ischaemia times of 1, 2, 3 and 4 hours, the 4 hour period of ischaemia was chosen for further analysis of the regeneration kinetics over a period of 21 days since it leads to regular and total destruction of the epithelium compatible with regeneration . This analysis included (1) a histological examination (semi-thin slices), (2) immunofluorescent detection of intestinal brush border proteins on frozen slices (villin, saccharase-isomaltase, aminopeptidase N, dipeptidylpeptidase-IV) and mucines, (3) measurement of specific intestinal hydrolase activities (saccharase, aminopeptidase N, dipeptidylpeptidase-IV and alkaline phosphatase) in enriched brush border fractions, and (4) an analysis of variations in intestinal flora . After the 4 hour ischaemia, total destruction of the epithelium with disappearance of the villin and intestinal hydrolases and disorganization of the mucosa invaded by mucosal lacks was observed . Epithelial regeneration was rapid and two days later the histological aspect of the mucosa showed apical expression (still discontinuous), villin and intestinal hydrolase activity . Luminal apical expression of the markers became continuous on day 4, demonstrating the total recovery of the intestinal barrier as confirmed by stable microbial flora . Mucine expression also returned to normal . This regeneration was however incomplete since the mucosa was seen to be flat, without villosities . Immunofluorescence showed the weak intensity of brush border activity and the very low specific activity of hydrolase . Values were below normal and did not start to rise again until day 21 . If serum levels and associated brush border markers could be measured and were significant, they could be specific markers of regeneration in double stomy ischaemic-revascularized intestine and thus eliminate the need for early second look laparotomy. Zh Mikrobiol Epidemiol Immunobiol, 1994 May-Jun, (3), 61 - 4 {The immunological efficacy of Francisella tularensis outer membranes for hamadryas baboons}; Khlebnikov VS et al.; The protective properties of the preparation of F . tularensis outer membranes (OM), obtained from F . tularensis vaccine strain 15, were studied in experiments on hamadryas baboons challenged subcutaneously with F . tularensis virulent strain Schu (nonarctic subspecies) . The subcutaneous immunization with the OM preparation prevented the development of clinically pronounced infection in more than 70% of the monkeys challenged with F . tularensis strain Schu in a dose of 787 live microbial cells 30 days after immunization . Antibody titers determined in the immunized monkeys with the use of the agglutination test (AT) and the passive hemagglutination test (PHAT) were usual in minimal diagnostic limits (1:80 for AT and 1:320 for PHAT) and did not significantly rise by day 20 after immunization . In all intact animals infected with F . tularensis strain Schu the development of the infectious process was registered, which was accompanied by a rise in temperature exceeding 39.5 degrees C and a rise in the titer of specific antibodies. Int J Immunopharmacol, 1994 May-Jun, 16(5-6), 419 - 24 Immunoglobulin Fab fragment-binding proteins; Bouvet JP; Five molecules are known to bind the Fab fragments of human immunoglobulins (Ig) . Microbial protein A and protein G are primarily Fc-binding molecules but can also bind other structures of the heavy chain, which are located in the variable domain of the third subgroup (VH3) and in the first constant domain of IgG (CH1 gamma), respectively . In contrast, the two other microbial receptors have a sole Ig-binding site, directed to chi chains (protein L) or to Ig polymers (protein P) . Protein Fv is synthesized by human liver cells and released in the digestive lumen, where it forms large complexes with secretory Ig after binding to the VH domains . These five molecules, in the main, bind cleaved Ig and most of them recognize all classes of antibodies . Bacterial molecules are, or can be, used as reagents to purify and detect Ig and fragments . Furthermore, a possible use in human therapy or vaccination is envisaged, and the human protein Fv is a key-factor in immune protection against intraluminal pathogens of the gut. Comp Biochem Physiol Pharmacol Toxicol Endocrinol, 1994 May, 108(1), 11 - 8 NO as an effector molecule of parasite killing: modulation of its synthesis by cytokines; Oswald IP et al.; It has recently been appreciated that NO, a molecule previously known to play a physiologic role in blood pressure regulation, is a major effector molecule of macrophage cytotoxicity against a variety of microbial targets, including protozoan and helminth parasites . NO production by macrophages is arginine dependent and catalyzed by a cytokine-inducible form of the NO synthase . This activity is positively controlled by several up-regulatory stimuli (including IFN-gamma, TNF-alpha, IL-2) and negatively controlled by others (principally IL-10, IL-4, TGF-beta) . Other cell types, such as endothelial cells and hepatocytes, display a similar capacity for NO production in response to cytokine stimulation . In murine models of leishmaniasis and schistosomiasis, in vivo NO synthesis correlates with protective immunity against infection . The effector molecule that plays a similar role in cell-mediated immunity in man has not yet been identified. J Antibiot (Tokyo), 1994 May, 47(5), 515 - 22 Benzomalvins, new substance P inhibitors from a Penicillium sp; Sun HH et al.; In the course of screening microbial broths for neurokinin receptor antagonists, a series of new benzodiazepines, benzomalvins A (1), B (2) and C (3), has been isolated from the culture broth of a fungus identified as a Penicillium sp . Benzomalvin A (1) showed inhibitory activity against substance P with Ki values of 12, 42 and 43 microM at the guinea pig, rat and human neurokinin NK1 receptors, respectively . Benzomalvins B (2) and C (3) were only weakly active . The structures of these compounds were determined by spectroscopic methods including MS measurements and NMR analysis. J Biol Chem, 1994 Apr 22, 269(16), 11743 - 50 3,5,3'-Triiodothyronine-induced carbamyl-phosphate synthetase gene expression is stabilized in the liver of Rana catesbeiana tadpoles during heat shock; Helbing CC et al.; One of many changes occurring during spontaneous and 3,5,3'-triiodothyronine (T3)-induced metamorphosis of the Rana catesbeiana tadpole is the permanent transition from an ammonotelic, aquatic larva to a ureotelic, terrestrial adult . T3-induced urea production is preceded by T3-induced elevation in the synthesis and level of liver-specific urea cycle enzymes essential for detoxication of ammonia in a terrestrial environment . This report focuses on establishing the effects heat shock (hs) has on the T3-induced expression of genes encoding three essential urea cycle enzymes . We demonstrate that hs stabilizes the intracellular existing levels of carbamyl-phosphate synthetase I (CPS I), the first enzyme in the urea cycle, while concurrently depressing its new synthesis . To establish the effects of hs on CPS I mRNA levels, we characterized cDNAs encoding an amphibian CPS I and demonstrate that it may represent an evolutionary link between microbial CPS and mammalian CPS I . Using this CPS I cDNA and other R . catesbeiana gene-specific probes, we demonstrate that hs depresses the level of T3-induced thyroid hormone receptor beta mRNAs but does not affect the level of T3-induced CPS I, ornithine transcarbamylase, and arginase mRNAs . These results support the contention that the hs response may involve the selective protection of some pre-existing mRNAs and proteins essential for an organism's survival. Biochim Biophys Acta, 1994 Apr 21, 1199(3), 285 - 92 DNA cleavage by Cu(II)-desferal: identification of C1'-hydroxylation as the initial event for DNA damage; Joshi RR et al.; Desferal, a siderophore of microbial origin is the only drug currently used for clinical treatment of a genetic disorder, thalassemia . By using a combination of HPLC and 31P-NMR, it is demonstrated that the Cu complex of desferal cleaves DNA, the primary site of hydroxyl radical attack being the sugar C1' in the minor groove, which leads to production of 5-methylene furanone . While no C5'-oxidation was observed, a minor process involving C4'-attack accompanies the above cleavage path . The oxidative cleavage of DNA observed with CuDFO may have implications in the emerging applications of desferal as a drug delivery agent and an antimalarial. J Immunol, 1994 Apr 15, 152(8), 4070 - 9 Binding of the terminal mannosyl units of lipoarabinomannan from a virulent strain of Mycobacterium tuberculosis to human macrophages; Schlesinger LS et al.; Recent studies from this laboratory have demonstrated that macrophage phagocytosis of virulent strains (Erdman and H37Rv), but not the attenuated H37Ra strain of Mycobacterium tuberculosis, is mediated by phagocyte mannose receptors (MR) in addition to complement receptors (CR1 and the leukocyte integrins CR3 and CR4) . Lipoarabinomannan (LAM) is a major surface lipoglycan of M . tuberculosis . LAM from the Erdman strain (Man-LAM) contains mannose oligosaccharides at the terminal portions of the molecule . This study investigated the ability of ManLAM to serve as a microbial ligand in adherence to human monocyte-derived macrophages (MDM) . Polystyrene microspheres were coated with known amounts of purified ManLAM, LAM without the terminal mannosyl units from an avirulent mycobacterium (AraLAM), lipomannan (LM), or buffer and incubated with MDM monolayers in the absence of serum . The presence of LAM on microspheres was confirmed by indirect immunofluorescence studies . Microspheres coated with ManLAM demonstrated a more than threefold increase in adherence to MDM when compared with microspheres coated with AraLAM, LM, or buffer and the low levels of adherence of microspheres in the latter three groups were comparable . Compared with control monolayers, selective down-modulation of MDM MR on a mannan substrate abrogated the enhanced adherence of microspheres mediated by ManLAM . Adherence of microspheres coated with AraLAM, LM, or buffer was not influenced by MR modulation . To confirm the importance of the terminal mannosyl units of ManLAM in the enhanced adherence of ManLAM microspheres to MDM, these units were selectively removed by exomannosidase treatment . The structure of LAM products before and after enzyme treatment was confirmed by high performance anion exchange chromatography with pulsed amperometric detection . Removal of the terminal mannosyl units abolished the capacity of ManLAM to mediate enhanced adherence of microspheres to MDM . Finally, preincubation of Erdman M . tuberculosis with CS-40, a mAb directed against LAM, resulted in a consistent inhibition of adherence of the bacteria to MDM (up to 49% inhibition), confirming a role for ManLAM on intact bacteria in adherence to MDM . Thus, we provide evidence for a novel receptor-ligand pathway in phagocytosis of M . tuberculosis that consists of MR on macrophages and mannosyl units at the terminal end of ManLAM, a major microbial surface lipoglycan. J Am Vet Med Assoc, 1994 Apr 15, 204(8), 1201 - 6 Characterization of naturally developing small intestinal bacterial overgrowth in 16 German shepherd dogs; Willard MD et al.; Sixteen German Shepherd Dogs were found, via quantitative microbial culture of intestinal fluid samples, to have small intestinal bacterial overgrowth (IBO) over an 11-month period . All dogs were deficient in serum IgA . Consistent clinical signs suggestive of an alimentary tract disorder were not observed . Serum cobalamin determinations were not helpful in detecting IBO . Serum folate concentrations had variable sensitivity and specificity for detecting dogs from which we could culture > or = 1 x 10(5) bacterial/ml from intestinal fluid samples in the nonfed state . Histologic and intestinal mucosal cytologic examinations were not useful in detecting IBO . Substantial within-dog and between-dog variation was found in the numbers and species of bacteria in the intestines . The difficulty in diagnosing IBO, the variability in organisms found in individual dogs on repeated sampling, the likelihood that intestinal fluid microbial cultures failed to diagnose IBO in some dogs, and the potential of IBO to be clinically inapparent were the most important findings in this study. Blood, 1994 Apr 15, 83(8), 2345 - 51 Differential effect of 4-hydroperoxycyclophosphamide and antimyeloid monoclonal antibodies on T and natural killer cells during bone marrow purging; Zhong RK et al.; Autologous bone marrow (BM) transplantation after high dose therapy is widely used to treat acute leukemia, lymphoma, and selected solid tumors . In studies of BM purging with chemical agents, monoclonal antibodies (MoAbs), or other agents, the emphasis has been on the efficacy of tumor cell removal and sparing of hematopoietic progenitor cells . Two commonly used methods of BM purging for patients with acute myeloid leukemia have been the drug 4-hydroperoxycyclophosphamide (4-HC) and (MoAbs) directed to myeloid antigens such as CD14, CD15, and CD33 . Although both methods of BM purging have potent activity against leukemia cells, 4-HC is also quite toxic to normal hematopoietic progenitor cells in the same concentrations that are used to deplete leukemia cells . To further characterize the cellular composition of BM after purging, we examined the effects of MoAbs plus complement and 4-HC on cells of the lymphoid lineage in the BM . 4-HC exerted a concentration-dependent cytotoxicity on clonogenic T lymphocytes, natural killer (NK) cells, and lymphokine (interleukin-2)-activated killer (LAK) cells, whereas the anti-CD14 and anti-CD15 MoAbs had little effect . At a concentration of 4-HC commonly used for BM purging (60 micrograms/mL), there were 4 to 5 logs of T-cell depletion and almost complete elimination of NK- and LAK-cell activity . In contrast, 4-HC at low concentrations (eg, 3 micrograms/mL) spared the majority of lymphoid cells suggesting that low concentration 4-HC combined with MoAb purging may be a desirable alternative to higher concentration 4-HC . These data indicate that purging with antimyeloid MoAbs, but not with 4-HC, spares the function of mature graft lymphocytes . Infusion of viable lymphocytes may be important for the transfer of immune memory against microbial and neoplastic antigens and may hasten immune reconstitution . In addition, mature graft lymphocytes may also be selectively activated and expanded in conjunction with interleukin-2 administration after BM transplantation. J Immunol, 1994 Apr 15, 152(8), 4110 - 8 Inactivation of nitric oxide synthase after prolonged incubation of mouse macrophages with IFN-gamma and bacterial lipopolysaccharide; Vodovotz Y et al.; Large amounts of nitric oxide (NO) are produced by the inducible isoform of NO synthase (iNOS) in many cell types once the iNOS gene is transcriptionally activated . In primary mouse peritoneal macrophages elicited by thioglycolate broth, expression of iNOS follows treatment with IFN-gamma and is synergistically increased by the addition of bacterial LPS . Expression of iNOS is suppressible at transcriptional and translational levels by certain cytokines and microbial products . The present study describes a novel form of inactivation of iNOS that is post-translational and nondegradative . Mouse peritoneal macrophages cultured in the presence of IFN-gamma alone or IFN-gamma plus LPS rapidly depleted the medium of L-arginine, a substrate for iNOS, and stopped producing NO . Repletion of L-arginine permitted cells treated with IFN-gamma alone to resume NO production for at least 5 days, leading to the release of more NO than macrophages were previously believed capable of generating . L-Arginine repletion also boosted NO production by macrophages cultured for up to 2 to 3 days in the presence of IFN-gamma plus LPS, but thereafter, iNOS was inactive in these cells whether or not L-arginine was repleted . Activity of iNOS could be restored by adding both L-arginine and fresh IFN-gamma with or without LPS, likely reflecting the synthesis of new enzyme . However, the inactivation of iNOS seen late in culture with a single application of IFN-gamma plus LPS could be attributed neither to loss of iNOS protein nor to its autoinactivation by NO . Thus, LPS, a co-inducer of iNOS, causes macrophages to inactivate iNOS about 3 days after the onset of its induction . The mechanism, which remains to be identified, is novel for iNOS, in that it decreases neither its amount nor its apparent molecular mass. Proc Natl Acad Sci U S A, 1994 Apr 12, 91(8), 3358 - 62 A beta-lactone related to lactacystin induces neurite outgrowth in a neuroblastoma cell line and inhibits cell cycle progression in an osteosarcoma cell line; Fenteany G et al.; Lactacystin, a microbial natural product, induces neurite outgrowth in Neuro 2A mouse neuroblastoma cells and inhibits progression of synchronized Neuro 2A cells and MG-63 human osteosarcoma cells beyond the G1 phase of the cell cycle . A related beta-lactone, clasto-lactacystin beta-lactone, formally the product of elimination of N-acetylcysteine from lactacystin, is also active, whereas the corresponding clastolactacystin dihydroxy acid is completely inactive . Structural analogs of lactacystin altered only in the N-acetylcysteine moiety are active, while structural or stereochemical modifications of the gamma-lactam ring or the hydroxyisobutyl group lead to partial or complete loss of activity . The inactive compounds do not antagonize the effects of lactacystin in either neurite outgrowth or cell cycle progression assays . The response to lactacystin involves induction of a predominantly bipolar morphology that is maximal 16-32 h after treatment and is distinct from the response to several other treatments that result in morphological differentiation . Neurite outgrowth in response to lactacystin appears to be dependent upon microtubule assembly, actin polymerization, and de novo protein synthesis . The observed structure-activity relationships suggest that lactacystin and its related beta-lactone may act via acylation of one or more relevant target molecule(s) in the cell. Med Device Technol, 1994 May, 5(4), 14 - 6 Cobalt-60: the heart of gamma-radiation sterilization; Brinston RM et al.; Currently, more than three million cubic metres of single-use medical devices are sterilized by gamma radiation each year . The wide use of this method of sterilization is a result of the lethal effects of ionizing radiation on microbial populations and the penetrative powers of cobalt-60 . This article describes how cobalt-60 is produced and used in gamma-radiation sterilization, and how it is disposed of once it has reached the end of its useful life . Cobalt-60 sources typically have a life of 20 years, at which point they are returned to the suppliers for re-encapsulation, reprocessing, recycling, or disposal. J Periodontol, 1994 Apr, 65(4), 303 - 8 Influence of tooth instrumentation roughness on subgingival microbial colonization; Leknes KN et al.; This study evaluated microbial colonization of periodontal pockets subjected to root instrumentation with a curet or a rotating diamond . Ten maxillary and 10 mandibular subgingival pockets were established in the canines of 5 beagle dogs . The subgingival root surface areas were debrided by a sharp curet or a flame-shaped, fine-grained, rotating diamond point . The dogs were fed a plaque-inducing diet for 70 days . Specimens from both instrumentation groups were then harvested and prepared for stereomicroscopic and scanning electron microscopic evaluation . Grading of the extent of subgingival colonization was performed in coded specimens directly on the fluorescent screen of the scanning electron microscope in a grid-counting system . Error of the method was assessed by duplicate counts . The subgingival root surface areas were divided into 3 zones: cervical, middle, and apical, and statistical differences between these zones as well as between the 2 instrumentation groups were calculated . The results revealed that curet-treated surfaces were smoother and promoted less subgingival colonization than diamond-treated surfaces . The difference in amount of bacterial colonization between the 2 groups was statistically significant (P < 0.05) in all zones . Bacterial colonization decreased in apical direction in both instrumentation groups . For the diamond-treated specimens, this decrease was significant (P < 0.05) between each of the 3 zones . In the curet-treated specimens, the decrease was significant only between the cervical and the apical zone (P < 0.05) . The present study has demonstrated that subgingival instrumentation roughness significantly influences the subgingival microbial colonization. Mol Pharmacol, 1994 Apr, 45(4), 724 - 30 RES-701-1, a novel, potent, endothelin type B receptor-selective antagonist of microbial origin; Tanaka T et al.; The unique cyclic peptide designated RES-701-1 blocked the binding of 125I-labeled endothelin (ET)-1 to bovine cerebellar membranes . ETB receptors are predominant in bovine cerebellum . However, in bovine lung membranes, where both ETA and ETB receptors are expressed, RES-701-1 inhibited 125I-ET-1 binding by up to 70%; RES-701-1, in the presence of the ETA-selective antagonist BQ-123 at 1 microM, displaced 125I-ET-1 binding completely . With membranes from transfected Chinese hamster ovary cells expressing the human ETA or ETB receptors, RES-701-1 inhibited 125I-ET-1 binding to the ETB receptor with an IC50 value of 10 nM but had no effect on 125I-ET-1 binding to the ETA receptor . Thus, RES-701-1 is highly specific for the ETB receptor; it has no effect on a number of other receptors . RES-701-1 selectively inhibited the ET-1-induced increase in intracellular Ca2+ concentration in COS-7 cells expressing the ETB receptor but did not inhibit the Ca2+ transient in ETA-expressing cells . When injected intravenously (250 nmol/kg) into anesthetized rats, RES-701-1 abolished the initial depressor response to ET-1 but enhanced the subsequent pressor response . These results suggest that RES-701-1 is a potent and specific antagonist for the ETB receptor and that RES-701-1 will be a powerful tool for understanding the physiological roles of this receptor. Hum Pathol, 1994 Apr, 25(4), 419 - 23 Mitochondrial complex I and III mutations and neutral-lipid storage in activated mononuclear macrophages and neutrophils: a case presenting with necrotizing myopathy, poikiloderma atrophicans vasculare, and xanthogranulomatous bursitis; Haferkamp O et al.; We report the case of a 57-year-old woman suffering from xanthogranulomatous bursitis, necrotizing myopathy, and poikiloderma atrophicans vasculare, which are associated with marked accumulation of neutral-lipid storage phagocytes . The observed lipid storage was restricted to activated phagocytes independent of the presence of tissue necrosis and was not seen either in circulating blood leukocytes or in muscle fibers . The patient's daughter disclosed xanthomatous inflammatory reaction with profound delay of wound healing secondary to pelviscopy . Examination of the mitochondrial DNAs of the patient, her daughter, and her two grandchildren revealed two homoplasmic mutations at positions 13708 and 15257 of the mitochondrial genome . We discuss the involvement of these mutations in the pathogenesis of xanthomatous and xanthogranulomatous inflammation . Further investigations are required to test whether impairment of aerobic energy production independent from mitochondrial DNA mutations (eg, by hypoxia or microbial toxins) similarly can cause the accumulation of lipid-laden macrophages and explain the persistency of xanthogranulomatous inflammation. Ann Allergy, 1994 Apr, 72(4), 307 - 16 AIDS-associated Reiter's syndrome; Altman EM et al.; Classically, Reiter's syndrome was defined as a triad of arthritis, urethritis, and conjunctivitis . In 1981, the American Rheumatism Association revised its defining criteria for Reiter's syndrome as an episode of peripheral arthritis of more than 1 month's duration occurring in association with urethritis and/or cervicitis . Reiter's syndrome is also associated with mucocutaneous lesions . Reiter's syndrome was first described in association with the human immuno-deficiency virus (HIV) in 1987 . The course of Reiter's syndrome in HIV is more severe, progressive, and refractory to treatment than in non-HIV-positive patients . The immunopathogenesis of Reiter's syndrome is linked to HLA-B27, which has been described as the disease susceptibility factor . The association of Reiter's syndrome and HLA-B27 positivity is 80% . Infectious agents may play a critical role in the initiation or perpetuation of Reiter's syndrome . It has been suggested that an amino acid sequence within the HLA-B27 molecule allows microbial peptides to bind and be presented to T cytotoxic cells (CD8), which results in a primary T cytotoxic cell response against various tissues . The role of the HIV in the pathogenesis of Reiter's syndrome is still being investigated . Human immunodeficiency virus may directly cause arthritis; it may increase the host's susceptibility to infection with arthritogenic organisms . Additionally, HIV infection increases the relative number of CD8 cells, which may play a key role in the pathogenesis of Reiter's syndrome . In this article, we present a case of Reiter's syndrome in an HLA-B27 and HIV-positive patient, and a review of the literature on the infectious, immunologic, and dermatologic aspects of Reiter's syndrome in HIV disease. Am J Clin Pathol, 1994 Apr, 101(4 Suppl 1), S18 - 21 The molecular approach to microbial diagnosis; Hillyard DR; Nucleic acid technology is reshaping the laboratory approach to infectious diseases . The intrinsic advantages of the molecular diagnostic approach, coupled with rapid technical progress in this field, ensure its expanding role in clinical microbiology and virology . Interpretation of molecular tests requires a thorough understanding of their theoretical foundations, and laboratory professionals should renew their commitment to education in this area. Eur J Immunol, 1994 Apr, 24(4), 991 - 8 A fungal metabolite which inhibits the interaction of CD4 with major histocompatibility complex-encoded class II molecules; Gammon G et al.; CD4, a cell-surface glycoprotein expressed on a subpopulation of T cells, is the receptor for class II molecules of the major histocompatibility complex (MHC II) and a receptor for the envelope glycoprotein (gp 120) of human immunodeficiency virus-1 (HIV-1) . Screening of microbial metabolites for CD4-binding activity using an enzyme-linked immunosorbent assay based on the binding of the CD4-specific monoclonal antibody (mAb), anti-Leu3a, identified a family of compounds comprising several novel polyketides . The parent compound (411F, Vinaxanthone) is a C28 molecule probably arising from a dimerization of two C14 polyketide units . It strongly inhibited the interaction of anti-Leu 3a and that of several other D1/D2 epitope-specific mAb with CD4, but only weakly inhibited the binding of HIV-1 gp120 . Binding of a representative MHC class II molecule, HLA-DRB*0401, was also inhibited by 411F with a comparable inhibitory concentration (IC50 = 1 microM) . In functional assays 411F inhibited antigen-induced CD4-dependent T cell proliferative responses of peripheral blood mononuclear cells . At the clonal level 411F exhibited selectivity in that the compound inhibited peptide-induced CD4+ T cell proliferative responses but not alloantigen-induced CD8+ T cell proliferation . It is hypothesized that 411F, a polyanionic compound in aqueous solution at neutral pH, inhibits CD4-dependent functions by binding over a broad area of the positively charged amino-terminal D1 and D2 domains implicated in the interaction with MHC II molecules . 411F has the potential for development as an immunosuppressive agent with a novel mechanism of action. J Nutr, 1994 Apr, 124(4), 566 - 70 Dietary soybean oil changes lipolytic rate and composition of fatty acids in plasma membranes of ovine adipocytes; Jenkins TC et al.; A study was conducted to determine which fatty acids in plasma membranes of adipose tissue from ruminants are changed when the diet is supplemented with unsaturated fatty acids and to determine the effect of the fat supplement on adipocyte metabolism . Ten sheep were randomly assigned to two isonitrogenous diets containing either no added fat (control) or 5 g soybean oil/100 g diet . Perirenal fat was removed at slaughter, adipocytes isolated by collagenase digestion, and plasma membranes prepared by centrifugation on a Percoll gradient . Feeding soybean oil to the sheep increased (P < 0.05) linoleic acid {18: 2(n-6)} concentration in subcutaneous fat and isolated adipocytes, suggesting partial escape of dietary unsaturated fatty acids from ruminal biohydrogenation . Soybean oil consumption also decreased (P < 0.05) concentrations of myristic acid, arachidonic acid {20: 4(n-6)} and anteiso 17:0 in plasma membranes, but increased (P < 0.05) trans 18:1 . Lipogenesis was not affected by diet, but lipolysis tended to be greater (P = 0.07) in sheep fed the soybean oil-containing diet than in those fed the control diet . In ruminants, fatty acids of ruminal origin, namely trans intermediates of biohydrogenation or branched-chain fatty acids of microbial lipid, may account for as much change in the composition of plasma membranes and in cellular metabolism as do the small quantities of unsaturated fatty acids in the diet that escape biohydrogenation. Crit Care Med, 1994 Apr, 22(4), 673 - 9 Circulating interleukin-8 concentrations in patients with multiple organ failure of septic and nonseptic origin; Marty C et al.; OBJECTIVES: Interleukin (IL)-8, a pro-inflammatory cytokine, is a potent chemoattractant factor and an activator of neutrophils produced by many cell types after stimulation by IL-1, tumor necrosis factor (TNF), or microbial products such as endotoxins . We investigated whether the presence of measurable IL-8 in plasma was associated with the clinical status of severely ill septic or nonseptic patients susceptible to the development of multiple organ failure . DESIGN: Cohort study . SETTING: A collaborative study between an intensive care unit and a research laboratory . SUBJECTS: Circulating IL-8 concentrations were measured in the plasma of 27 patients with sepsis syndrome and in 16 patients with noninfectious shock because these two conditions put patients at risk for the development of multiple organ failure . Sixteen of 27 patients with severe infection and 13 of 16 patients with noninfectious pathologies developed multiple organ failure . MEASUREMENTS AND MAIN RESULTS: A specific enzyme-linked immunosorbent assay (ELISA) for IL-8 was set up with a monoclonal and a rabbit polyclonal antihuman IL-8 using a sandwich technique . High concentrations of circulating IL-8 were found in the plasma of patients with sepsis syndrome . Among septic patients, a significant difference was observed between concentrations of IL-8 in survivors (n = 16) and nonsurvivors (n = 11) (81 +/- 13 pg/mL vs . 3326 +/- 1219 pg/mL, respectively; p = .001) . A correlation was noticed between plasma IL-8 and IL-6 concentrations (r2 = .42; p = .001), while no correlation was observed between IL-8 and TNF-alpha values, or between IL-8 and IL-1 beta . Although the mortality rate of nonseptic, multiple organ failure patients was 92%, low plasma concentrations of IL-8 were found (78 +/- 34 pg/mL), while high plasma concentrations were measured in septic, multiple organ failure patients (mortality rate 69%) who were sampled at a similar stage . By contrast, increased IL-6 values were observed in both septic and nonseptic, multiple organ failure patients . CONCLUSIONS: In septic patients, high amounts of circulating IL-8 concentrations correlate with fatal outcome, whereas only low plasma concentrations of IL-8 are present in patients with nonseptic, multiple organ failure . This finding suggests that the signals involved in the exacerbation of IL-8 production are different, depending on infectious or noninfectious etiology. J Oral Maxillofac Surg, 1994 Apr, 52(4), 393 - 6 Stability of reconstituted methohexital sodium; Beeman CS et al.; The purpose of this study was to determine the stability of reconstituted solutions of methohexital sodium over a 6-week period . Stability of methohexital was examined using reversed-phase high-performance liquid chromatography . The results indicate that reconstituted methohexital is extremely stable for up to 6 weeks when stored at 4 degrees C . When stored at room temperature, reconstituted solutions of methohexital contained increasing levels of degradation products and showed a corresponding decrease in methohexital over a 6-week period . However, the rate of degradation of the drug was slow, with less than 10% of the methohexital undergoing breakdown . In addition, tests for microbial contamination of the solutions stored at room temperature and under refrigeration were negative for up to 6 weeks . This study demonstrates that methohexital, when stored under refrigeration for up to 6 weeks, is virtually chemically identical to a freshly reconstituted solution of the drug . When stored at room temperature, there is some degradation of the drug, but it is not known whether the small amount of degradation is clinically significant . This study emphasizes the importance of obtaining scientific data to support changes in guidelines related to handling and storage of drugs. J Biochem (Tokyo), 1994 Apr, 115(4), 743 - 51 Isolation and characterization of Streptoverticillium anticoagulant (SAC), a novel protein inhibitor of blood coagulation produced by Streptoverticillium cinnamoneum subsp . cinnamoneum; Tanabe M et al.; Three Streptoverticillium anticoagulants, SAC I, II, and III, which strongly inhibit human intrinsic blood coagulation, were each isolated in a homogeneous form from a culture fluid of Streptoverticillium cinnamoneum subsp . cinnamoneum IFO 12852 . SAC I, II, and III are simple proteins with molecular weights of around 12,000, and with isoelectric points of 9.7, 9.7, and 9.9, respectively . Their amino acid compositions are similar and each SAC possesses two disulfide bonds . The COOH-terminal residue of each of these proteins is phenylalanine . Together with the similarity of their protein chemical properties, the results of NH2-terminal amino acid sequence analysis of these SAC proteins strongly suggested that the deletion of Ser-Leu and Ser-Leu-Tyr from the NH2-terminus of SAC I (Ser-Leu-Tyr-Ala-Pro-...) results in the generation of SAC II and III, respectively . The amount of each SAC necessary to double the partial thromboplastin time was around 5 micrograms/ml . SAC I inhibited activated human factor XII and human plasma kallikrein . It also inhibited, but to a lesser extent, activated factor X . The inhibition constants (Ki) of SAC I toward activated factor XII and plasma kallikrein were 5.3 x 10(-8) and 7.2 x 10(-9) M, respectively . The SACs also inhibited some microbial serine proteases such as subtilisin Carlsberg and, to a lesser extent, mammalian serine proteases including bovine trypsin and alpha-chymotrypsin . Of these three inhibitors, only SAC I inhibited metalloproteases such as thermolysin in addition to these serine proteases. J Oral Pathol Med, 1994 Apr, 23(4), 168 - 71 The relationship between micronutrient depletion and oral health in geriatrics; Sweeney MP et al.; Changes in the oral microbial flora, some of which are related to mucosal disease, have been detected in the elderly, but the causes are not fully understood . This study has examined the possible role of micronutrient depletions in the reduced colonisation resistance and oral infection exhibited by some elderly subjects . The oral health, oral microbiology and micronutrient status of 37 geriatric patients aged 65-91 years (mean 81 years) were examined . Ten of the patients had no oral mucosal disease . Mucosal pathology in the remainder included erythema (27%), denture stomatitis (24%), angular cheilitis (16%) and atrophic glossitis (41%) . Those with mucosal pathology had significantly lower serum iron concentrations (P = 0.02) . Serum or plasma concentrations of zinc, copper, selenium, C-reactive protein, transferrin, caeruloplasmin, albumin, vitamin A and vitamin E were not significantly different between those with oral disease and those with healthy mouths . Similarly, activity of the selenium-containing enzyme, red cell glutathione peroxidase, did not differ significantly between the two groups . In both groups, plasma selenium concentrations (82%), red cell glutathione peroxidase activity (47%), plasma zinc concentrations (58%) and albumin concentrations (44%) tended to be below the lower limit of the reference interval . The influence of subclinical infection on these values is discussed. Immunology, 1994 Apr, 81(4), 564 - 8 Proliferative and cytolytic responses of human gamma delta T cells display a distinct specificity pattern; Haecker G et al.; The function and physiological role of gamma delta T cells are still unknown . Concerning the specificity of these cells, a proliferative response towards microbial ligands has been noted, whereas in terms of effector functions in humans a cytolytic activity against a variety of tumour targets is most prominent . Here we show data demonstrating that the cytolytic activity of activated human gamma delta T cells does not reflect the specificity of these cells in primary in vitro stimulation; moreover, we provide evidence that the recognition of target cells by gamma delta T cells can have different qualities . gamma delta T cells proliferate vigorously in primary in vitro reaction upon stimulation with various B-cell tumour lines but not with the T-cell lines Jurkat or Molt-4 . However, gamma delta T cells stimulated primarily with phytohaemagglutinin or with cells from B-cell lines gain unrestricted cytolytic activity against a broad set of tumour targets, including Jurkat and Molt-4; the same set of targets is capable of inducing release of serine esterases (SE) from gamma delta T-effector cells . Whereas the cytolytic activity in the 51Cr-assay against the B-cell lines and against Molt-4 depends on the presence of Ca2+ ions in the assay, the lysis of Jurkat cells is only slightly reduced upon removal of Ca2+ from the medium; the SE release, however, is Ca2+ dependent in all cases . Taken together, these data suggest several different ways of target cell recognition by gamma delta T cells leading to either proliferation or triggering of cytolytic activity, and argue against an involvement of the gamma delta T-cell receptor in the cytotoxic activity of gamma delta T cells. Ann Pharmacother, 1994 Apr, 28(4), 451 - 5 Compatibility of oral morphine sulfate solution with enteral feeding products; Udeani GO et al.; OBJECTIVE: Patients with terminal cancer often receive continuous enteral nutrition and oral medications concomitantly through nasogastric or gastrostomy feeding tubes . This study evaluated in vitro the compatibility of morphine sulfate (MS) solution 2 mg/mL (Roxane Laboratories) with three enteral nutrition products (Jevity {J}, Osmolite-HN {O}, and Pulmocare {P}) at 22 and 37 degrees C for 48 hours and J alone at 50 degrees C for 48 hours . METHODS: Mixtures containing 1 mg/mL MS were prepared with each enteral product: J, O, and P (Ross Laboratories) . Serial samples (1 mL) were collected from each mixture and analyzed for morphine by reverse-phase HPLC . An analog pH meter was used to measure the pH of each mixture at scheduled intervals . RESULTS: The addition of MS 2 mg/mL (MS2) to J caused an immediate decrease in pH from 6.24 +/- 0.01 to 4.96 +/- 0.05 and a noticeable precipitate/phase separation . No phase separation was observed with a 1 mg/mL mixture of MS and J, O, and P when they were prepared with a more concentrated MS solution (20 mg/mL, MS20) (Roxanol Intensol) . The pH declined linearly for all three enteral feeding products as the MS20 concentration was increased from 0 to 1 mg/mL . The precipitate observed in the mixture of MS2 with J was probably caused by the decrease in pH, which was caused by the greater volume fraction of MS solution . The concentration of morphine in the supernatant of a MS2/J solution was 0.83 mg/mL, and the concentration of MS in a homogeneous MS20/J solution was 0.86 mg/mL . At 48 hours, there was negligible (< 2 percent) morphine decomposition in all MS admixtures at all temperatures . No microbial growth was observed in any admixture at 24 hours . Electrophoretic analysis demonstrated equal protein migration and molecular weight distribution for J and MS/J solutions . CONCLUSIONS: MS is stable in enteral feeding solutions at temperatures from 22 to 50 degrees C . MS2 is associated with a pH-dependent protein precipitation (but not destruction of the proteins), resulting in disproportionate concentrations of morphine in the supernatant and precipitate . This incompatibility may adversely affect enteral feeding analgesic delivery . We, therefore, recommend MS 20 mg/mL for this method of oral MS delivery, because of its superior compatibility and stability with enteral feeding products. Lab Anim, 1994 Apr, 28(2), 158 - 71 Twenty-five years of progress in laboratory animal science; Quimby FW; During the past 25 years tremendous improvements have been made in the field of laboratory animal science . Refinements in genetic and microbial quality assurance and animal housing coupled with the development of professional expertise has contributed to enhanced animal well-being and a reduction in the variability of data collected from research animals . These advances occurred concomitant with an increased public awareness of research animal use . In 1967 Laboratory Animals Ltd . published the first issue of Laboratory Animals . In celebration of its Silver Jubilee, I will briefly highlight some of the changes which occurred in the field of laboratory animal science since 1967 and some of the medical advances which depended on animal-based research. Appl Environ Microbiol, 1994 Apr, 60(4), 1116 - 20 Use of gene probes to aid in recovery and identification of functionally dominant 2,4-dichlorophenoxyacetic acid-degrading populations in soil; Ka JO et al.; The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was applied to soils in microcosms, and degradation was monitored after each of five repeated additions . Total DNAs were isolated from soil bacterial communities after each 2,4-D treatment . The DNA samples were analyzed on slot blots and Southern blots by using a tfdA gene probe subcloned from plasmid pJP4 and a Spa probe derived from a different 2,4-D-degrading isolate, a Sphingomonas paucimobilis strain . 2,4-D applied to soil was quickly degraded by indigenous microbial populations . As determined by slot blot analyses of DNA from a Michigan soil, the increase in hybridization signal in response to 2,4-D treatments was greater with the Spa probe than with the tfdA probe . In contrast, the DNA from a Saskatchewan soil exhibited an increase in hybridization signal with the tfdA probe . This indicated that a population with 2,4-D-degradative gene sequences different from the tfdA gene sequence was dominant in the Michigan site, but not in the Saskatchewan site . A Southern blot analysis of DNA from Michigan soil showed that the dominant 2,4-D-degrading population was S . paucimobilis 1443 . A less dominant 2,4-D-degrading population was detected with the tfdA probe; further analysis revealed that this population was a Pseudomonas pickettii 712 . These gene probe analyses revealed that an important population carrying out 2,4-D degradation was not detected when the canonical tfdA gene probe was used . After a series of new strains were isolated, we identified a probe to detect and identify the dominant members of this new group. J Anim Sci, 1994 Apr, 72(4), 1023 - 8 Concentrations of folates in ruminal content of steers: responses to a dietary supplement of folic acid in relation with the nature of the diet; Girard CL et al.; In an attempt to evaluate the ruminal effects of dietary supplements of folic acid, eight steers (352 +/- 27 kg BW) fitted with a ruminal cannula were randomly assigned to a replicated 4 x 4 Latin square design . The treatments were 70% rolled barley + 30% timothy hay (HC), HC + 2 mg of folic acid per kilogram of BW (HC + FA), 30% rolled barley + 70% timothy hay (HF), and HF + 2 mg of folic acid per kilogram of BW (HF + FA) . After 5 wk of adaptation to the dietary treatments, ruminal contents were sampled over three consecutive days, at 1, 2, 4, 8, 12, and 23 h after feed distribution . Concentrations of folates in solid and liquid ruminal fractions were increased by the dietary supplement of folic acid (P = .0001) and by the ingestion of concentrate compared with hay-based diets (P < .05) . Preprandial concentrations of serum folates were not affected by the nature of the diet when steers received no folic acid but the increase of serum folates induced by the dietary supplement of folic acid was more important in steers fed concentrates than in those fed hay-based diets (diet x supplement of folic acid interaction P = .002) . Microbial protein (P = .004) and microbial mass (P = .002) in ruminal fluid were increased with concentrate-based diets compared with hay-based diets; folic acid did not have any effect on these variables (P > .05) . In conclusion, concentrations of folates in ruminal contents were affected by dietary supplements of folic acid and by the nature of the diet.(ABSTRACT TRUNCATED AT 250 WORDS) Sports Med, 1994 Apr, 17(4), 245 - 58 Regulation of neutrophil function during exercise; Pyne DB; In recent years there has been considerable interest in how exercise and training may affect the immune system . There is now substantial cross-sectional and epidemiological evidence that exercise causes significant changes in the distribution and function of a number of cellular and humoral immune parameters . Neutrophils represent one of the key nonspecific host defence cell populations responsible for the phagocytosis of many microbial, bacterial and viral pathogens . The neutrophil is also known to be involved in the synthesis and release of immunomodulatory cytokines that influence both T cell and B cell activities . Therefore, it plays an important role in both the efferent (phagocytosis and degranulation) and afferent (release of immunomodulatory molecules) limbs of the immune response . Neutrophils and macrophages respond both to phagocytosable particles (e.g . bacteria, viruses and cell debris) and to a number of soluble factors . There is an increase in the number of circulating neutrophils with exercise as a result of demargination of cells from endothelial tissues (mediated by catecholamines) and bone marrow (mediated by cortisol), or as part of the phagocytic and inflammatory response to exercise-induced tissue damage . Following exercise-induced mobilisation into the circulation and migration into tissues, neutrophils undergo adherence, phagocytosis (engulfment) of bacteria or tissue fragments, degranulation of cytoplasmic granules and, ultimately, activation of the respiratory burst . The capacity of the respiratory burst largely determines the cytotoxic potential of the neutrophil . The respiratory burst involves a sudden increase in nonmitochondrial oxidative metabolism, resulting in the production of the superoxide anion (O2-) and other reactive oxygen species by the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase enzyme complex located at the plasma membrane . Although the biochemistry of the respiratory burst has been well studied, the mechanisms by which exercise and training may influence its activity are not well characterised or understood . Studies on the acute effects of exercise show that exercise generally elicits an initial activation of neutrophils-evidenced by release of cytoplasmic enzymes (degranulation) with secondary changes in key effector functions such as the phagocytic and respiratory burst activity . The nature of the functional changes is still unclear, as some studies show a transient suppression of the respiratory burst and/or phagocytic capacity immediately after exercise, while others report that moderate intensity exercise elicits an enhanced response . The variability in findings may be attributable to differences in the age, gender and initial fitness levels of the people studied, the intensity and duration of the exercise protocols used, and the different methodological procedures employed.(ABSTRACT TRUNCATED AT 400 WORDS) Appl Environ Microbiol, 1994 Apr, 60(4), 1241 - 8 Quantification of methanogenic groups in anaerobic biological reactors by oligonucleotide probe hybridization; Raskin L et al.; The microbial community structure of anaerobic biological reactors was evaluated by using oligonucleotide probes complementary to conserved tracts of the 16S rRNAs of phylogenetically defined groups of methanogens . Phylogenetically defined groups of methanogens were quantified and visualized, respectively, by hybridization of 32P- and fluorescent-dye-labeled probes to the 16S rRNAs from samples taken from laboratory acetate-fed chemostats, laboratory municipal solid waste digestors, and full-scale sewage sludge digestors . Methanosarcina species, members of the order Methanobacteriales, and Methanosaeta species were the most abundant methanogens present in the chemostats, the solid-waste digestors, and the sewage sludge digestors, respectively. J Neurochem, 1994 Apr, 62(4), 1319 - 29 Staurosporine, K-252a, and K-252b stabilize calcium homeostasis and promote survival of CNS neurons in the absence of glucose; Cheng B et al.; Staurosporine, K-252a, and the 9-carboxylic related compound K-252b are low-molecular-weight alkaloids from microbial origin that at high concentrations are kinase inhibitors and can antagonize the effects of neuronal growth factors . Paradoxically, we have found that very low concentrations of these agents (10 fM-10 nM) prolong the survival of hippocampal, septal, and cortical neurons deprived of glucose . These agents did not prevent the depletion of ATP caused by glucose deprivation . The large elevation of intracellular calcium levels that normally mediates glucose deprivation-induced damage was attenuated by staurosporine, K-252a, and K-252b . Western blot analysis using antiphosphotyrosine antibody showed that staurosporine and the K-252 compounds (10-100 pM) stimulated tyrosine phosphorylation of several different proteins . The tyrosine kinase inhibitor genistein significantly reduced the protective effect of staurosporine and the K-252 compounds, indicating that tyrosine phosphorylation was required for neuroprotection by these compounds . Taken together, the data demonstrate that low concentrations of staurosporine and the K-252 compounds can stabilize calcium homeostasis, possibly by a mechanism involving activation of receptor tyrosine kinase transduction pathways. Proc Natl Acad Sci U S A, 1994 Mar 29, 91(7), 2634 - 8 Use of genetic recombination as a reporter of gene expression; Camilli A et al.; An understanding of the patterns of gene expression in response to specific environmental signals can yield insight into a variety of complex biological systems such as microbial-host interactions, developmental cycles, cellular differentiation, ontogeny, etc . To extend the utility of the reporter gene fusion approach to such studies, we have constructed a gene expression reporter cassette that permits the generation of transcriptional fusions to tnpR encoding resolvase, a site-specific recombinase of the transposable element gamma delta . Induction of the transcriptional fusions results in production of resolvase, which in turn, catalyzes excision of a linked tetracycline-resistance reporter gene flanked by direct repeats of res, the DNA sequences at which resolvase functions . The loss of tetracycline resistance in descendant bacteria serves as a permanent and heritable marker of prior gene expression . This gene fusion approach will allow us to assay the induction of gene expression in as few as one cell . Additionally, gene expression can be assayed at a later time and/or different place from the inducing environment facilitating the study of gene expression in complex environments such as animal tissues. Sci Total Environ, 1994 Mar 15, 142(3), 157 - 62 Dehydrogenase activity of the microbial biomass in soils from a field experiment amended with heavy metal contaminated sewage sludges; Obbard JP et al.; Dehydrogenase activity (DHA) of the microbial biomass was measured in sewage sludge amended soil samples collected from the Braunschweig experimental site, Germany . The site had received additions of sludge with or without heavy metals at two application rates (100 m3/ha per year and 300 m3/ha per year) on soils of 'low' (4.8-5.8) and 'high' (5.4-7.0) pH since 1980 . DHA was found to be a sensitive and precise assay for determining the effect of heavy metals on substrate-induced (glucose) microbial biomass in sewage sludge amended soils . Effects on DHA were determined in relation to heavy metal concentrations and other soil factors . Addition of relatively uncontaminated sludge enhanced DHA, but this was dependent on the level and type of sludge addition . Adverse metal effects were only significant in the most contaminated soils where sludge had been added to the 'high' and 'low' pH treatments at Braunschweig . However, these effects were small compared to the effects of high rates of sludge addition alone, despite exceeding statutory limits for Zn and Cu, where concentrations reached 341 and 99 micrograms/g, respectively. J Immunol, 1994 Mar 15, 152(6), 2930 - 7 Intracellular infection by Leishmania donovani inhibits macrophage apoptosis; Moore KJ et al.; The phagocytic macrophage plays a critical role in host immune responses to microbial infection, and represents a major source of inflammatory and growth cytokines . Intramacrophage infection by the protozoan parasite Leishmania donovani results in increased viability of the host cell in the absence of exogenous growth factor . We demonstrate that infection of bone marrow-derived macrophages (BMMs) by L . donovani promastigotes or treatment of BMMs with lipophosphoglycan LPG, the major surface molecule of the promastigote, inhibits apoptosis in the macrophage induced by the removal of macrophage (M)-CSF . This effect was also achieved by supernatants collected from L . donovani-infected macrophages, implicating the elaboration of a soluble factor by infected cells as the mediator of this inhibition . To identify candidate factors, reverse transcription PCR was employed to characterize the mRNA cytokine profile of infected macrophages . L . donovani infection of BMMs was found to induce gene expression for granulocyte-macrophage CSF, TNF-alpha, TGF-beta, and IL-6, but not M-CSF or IL-1 beta . Of the cytokines induced by L . donovani, rTNF-alpha and recombinant granulocyte-macrophage CSF were shown to inhibit apoptosis of BMMs induced by the removal of M-CSF . The amount of these cytokines in L . donovani-infected cell supernatants was quantified by ELISA . The mechanism by which L . donovani may inhibit apoptosis is discussed. J Immunol, 1994 Mar 15, 152(6), 3128 - 36 New monoclonal antibody (23D12) recognizing three different V gamma elements of the human gamma delta T cell receptor . 23D12+ cells comprise a major subpopulation of gamma delta T cells in postnatal thymus; Kabelitz D et al.; The gamma delta TCR is expressed on 1 to 5% of CD3+ human peripheral blood T lymphocytes . The majority of peripheral blood gamma delta T cells expresses V gamma 9 paired with V delta 2; this subset strongly responds to certain microbial ligands . Other gamma delta T cell subsets with unknown Ag specificity expressing different V gamma elements are present in peripheral blood and lymphoid tissue . We describe a new anti-human V gamma mAb termed 23D12 with unusual specificity . As revealed by analysis of a large number of T cell clones and transfectants expressing molecularly well-defined gamma delta TCR, mAb 23D12 recognized several, but not all, members of the human V gamma 1 family, specifically V gamma 2, V gamma 3, and V gamma 4 but not V gamma 5 or V gamma 8 . In combination with available mAb against V gamma 4, mAb 23D12 was used to identify V gamma 2- or V gamma 3-bearing cells . On average, 23D12+ cells accounted for 18% of peripheral blood gamma delta T cells and 56% of postnatal gamma delta thymocytes . In combination with anti-V gamma 9 mAb, mAb 23D12 23D12 identified gamma delta cells expressing V elements other than V gamma 2, V gamma 3, V gamma 4, or V gamma 9 . Such cells are detectable in peripheral blood and postnatal thymus . Using mAb 23D12, we also confirmed the appearance of two distinct TCR gamma-chains on the surface of some gamma delta T cells. Biochim Biophys Acta, 1994 Mar 8, 1184(2-3), 291 - 5 Kinetics of ligand binding of cytochrome oxidases: a comparative study; Basu A et al.; The plethora of microbial oxidases revealed by photochemical action spectra (Chance, B . (1989)) Biochim . Biophys . Acta 1000, 345-347) has led to detailed identification, purification and overproduction in many species, to the point where kinetic comparison of properties seems to allow structure/function deductions . This work compares the carbon monoxide recombination of five types of oxidases obtained from various organisms . The results are plotted in an Arrhenius-type plot and suggest that the carbon monoxide ligation is a sensitive indicator of the heme environment specific for an oxidase expressed under a given oxygen concentration . This survey of the carbon monoxide recombination kinetics of naturally occurring cytochrome oxidases in whole cells shows evidence for structural control of the reaction kinetics. Plant Mol Biol, 1994 Mar, 24(5), 733 - 41 Isolation and characterization of a cDNA from flowers of Cynara cardunculus encoding cyprosin (an aspartic proteinase) and its use to study the organ-specific expression of cyprosin; Cordeiro MC et al.; Poly(A)+ RNA isolated from flower buds of Cynara cardunculus has been used to prepare a cDNA library . Screening of the cDNA after expression of cloned DNA with antibodies raised against the large subunit of cyprosin 3 resulted in the isolation of six positive clones . One of these clones (cypro1s; a 1.7 kb Eco RI fragment) codes for cyprosin . The nucleotide sequence contain a 1419 bp open reading frame coding for 473 amino acids (aa) including a putative full-length mature protein (440 aa) and a partial prosequence (33 aa) . Cypro1s contains a 162 bp 3' non-coding region followed by a poly(A) tail . The deduced amino acid sequence shows high homology to other plant aspartic proteinases . The homology to mammalian and microbial aspartic proteinases is somewhat lower . Plant aspartic proteinases contain an insert of around 100 aa . We are modelling where this plant-specific insert will appear in the structure of cyprosin . Using cypro1s as a probe in northern blot analysis, the expression of cyprosin in developing flowers and other tissues has been studied . The signal on the northern blot increased for RNA samples from early (flower buds 6 mm in length) to later stages of floral development (flower buds up to 40 mm in length) . In late stages of floral development (open flowers 50 mm in length and styles from such flowers) no hybridization signal was visualized showing that the synthesis of mRNA encoding the cyprosin starts in early stages of floral development and switches off at maturation of the flower.(ABSTRACT TRUNCATED AT 250 WORDS) J Anim Sci, 1994 Mar, 72(3), 572 - 6 Laboratory and field evaluation of commercial feed preservatives in the diet of nursery pigs; Rahnema S et al.; A two-part study was conducted to compare the effectiveness of 10 neutralized preservatives as inhibitors of microbial activity on cracked shelled corn at two moisture levels (15 and 18%) and to evaluate the performance of nursery pigs fed diets containing the two most effective preservatives selected from part one of this study . In part one, for each of the three replications (15 d), moisture content of the cracked corn was adjusted to 15 and 18% . Preservatives were diluted (1:1) with water and sprayed on 300 g of ground corn . Treated corn was then divided into two equal parts and placed in 500-mL sterilized Erlenmeyer flasks, covered with sterile cotton plugs, and incubated at 31 degrees C . Several preservatives were as effective as propionic acid in inhibiting microbial growth . Liquid Myco Curb (MC) and Sal Curb (SC) inhibited CO2 production by 12.7 and 13 d with 15 and 18% moisture corn, respectively . Combining the data for 15 and 18% moisture corn, Sal Curb inhibited microbial growth on corn the longest (12.2 d) . The second part of this study consisted of two replicates of a randomized complete block design experiment to evaluate the palatability, ADG, and gain:feed ratio of nursery pigs fed pelleted diets containing 1 kg/t of diet of either MC, SC, or no preservative . Pigs were blocked by sex and weight and randomly assigned to the treatments . Daily feed, weekly feed refusals, and weekly weights were recorded.(ABSTRACT TRUNCATED AT 250 WORDS) J Anim Sci, 1994 Mar, 72(3), 565 - 71 Digestibility, nitrogen utilization, and voluntary intake of ensiled crab waste-wheat straw mixtures fed to sheep; Abazinge MD et al.; Crab waste and wheat (Triticum aestivum L.) straw mixtures, ensiled with different additives, were evaluated in metabolism and palatability trials . Crab waste and straw were mixed in proportions of 1:1, wet basis, with 20% water and different additives, and ensiled in 210-L metal drums double-lined with polyethylene bags . Thirty crossbred wethers (40 kg initial BW) were fed a 1) basal diet consisting of 75% orchardgrass (Dactylis glomerata L.) hay and 25% concentrate, 2) ensiled crab waste-wheat straw, with 16% (vol/wt) added glacial acetic acid, 3) crab waste-wheat straw ensiled with 20% dry molasses, 4) crab waste-wheat straw ensiled with 20% dry molasses and a microbial inoculant, and 5) ensiled wheat straw supplemented with urea . Apparent digestibility of DM and CP was lower (P < .05) for acetic acid-treated silages than for silages containing molasses . Nitrogen retention was higher (P < .05) for molasses-inoculant-treated silage than for the molasses-treated silage (5.4 vs 3.9 g/d) . Ruminal NH3 N and blood urea N were higher (P < .05) for lambs fed the molasses-treated silages than for those receiving the acetic acid-treated crab waste mixture . Among the wethers fed crab waste silages, intake was lower (P < .01) for wethers receiving the acetic acid-treated silage than for those fed the molasses-treated mixtures . Treatment of crab waste-straw mixtures with molasses produced a palatable silage that was efficiently utilized by wethers. FEMS Microbiol Lett, 1994 Mar 1, 116(3), 283 - 6 Analysis of low-molecular mass products from biosolubilized coal; Toth-Allen J et al.; A relatively simple, rapid sample preparation method has been developed for analysis of low-molecular mass compounds present in soluble coal products generated by microbial coal solubilizing agents . Acidification of the sample followed by direct extraction into hexanes is coupled with gas chromatography/mass spectrometry analysis for characterization of the soluble coal products . Characterization of the products can contribute to a more complete understanding of the solubilization processes involved, provide further information as to the structure of coal and identify products of potential commercial value. Kansenshogaku Zasshi, 1994 Mar, 68(3), 332 - 8 {Analysis of complement-mediated phagocytosis in systemic lupus erythematosus model mice, NZB/W F1}; Onogawa T et al.; We have attempted to examine the cause of lowering phagocytic activity of phagocytes on clearance of bacteria in SLE patients . The experiments were performed in SLE model mice, NZB/WF1 female mice (BWF1) . The ratio of the cells which phagocytized fluorescent microspheres and possessed Mac-1 on both peripheral blood leukocytes (PBL) and peritoneal macrophages (PMo) in BWF1 female mice was shown decreasing by using the flow cytometric method before the present of typical symptoms of SLE (under 25 weeks-old), i.e., the appearance of ANA and IgG deposits in glomeruli . In a period of showing the symptoms of SLE (over 25 weeks-old), the ratio of Mac-1 positive cells on PBL increased, but phagocytic function of these cells did not increase . On the other hand, on PMo, they decreased together in that period . Moreover, the phagocytosis of PMo in 15, 25, 35 weeks-old mice against fluorescent microspheres showed a significant increase (1.7 times) by replacing opsonin with normal (ddY) murine serum instead of BWF1 murine serum, and the phagocytosis of PMo treated with anti-Mac-1 antibody (M1/70) showed a significant inhibition (46%) against that of untreated PMo . These results indicate that lowering phagocytic activity of phagocytes on primary defence against microbial infections in SLE patients is due possibly to decrease of C3 activity in the serum rather than a decrease of positive percentage and function of Mac-1 on these cells. J Antibiot (Tokyo), 1994 Mar, 47(3), 276 - 80 RES-701-1, a novel and selective endothelin type B receptor antagonist produced by Streptomyces sp . RE-701 . II . Determination of the primary sequence; Yamasaki M et al.; The structure of RES-701-1, a novel microbial endothelin type B receptor antagonist, was determined . Protein chemical data and FAB-MS have identified RES-701-1 to be a cyclic polypeptide consisting of 16 common L-amino acids . This compound is so stable against proteolysis that its enzymatic digestion under standard conditions proved to be very difficult . Therefore, the primary sequence of RES-701-1 was determined by the application of advanced protein chemical methods to be Gly1-Asn2-Trp3-His4-Gly5-Thr6-Ala7-Pro8-++ +Asp9-Trp10-Phe11-Phe12-Asn13- Tyr14-Tyr15-Trp16 . The compound is cyclized between the beta-carboxyl group of Asp9 and the alpha-amino group of Gly1. Cornea, 1994 Mar, 13(2), 148 - 55 A rapid fluorometric assay for tear fluid plasmin activity; Tervo T et al.; A rapid (5- to 10-min), sensitive (detection limit 0.6 IU/L), and moderately specific fluorometric plasmin assay for small volume tear fluid samples was developed . Addition of albumin (up to 0.1% final concentration) to the assay buffer improved the sensitivity of the test so that plasmin activity in healthy controls could be detected . pH in the reaction buffer was 8.0, Michaelis-Menten constant for the substrate, H-D-Val-Leu-Lys.7-amido-4-methyl-coumarin (AMC), was 0.28 mM, and final substrate concentration in the reaction buffer was 1 mM . Intra- and interassay imprecisions were 1.6 and 4.4%, respectively at a plasmin level of 10 IU/L . Tear fluid flow was significantly higher in the patients than in the healthy controls, and this dilatory effect must be considered when using plasmin determination for diagnostic purposes . This effect was counteracted by correcting the plasmin activity values by tear fluid flow . Plasmin flux is plasmin activity (microIU) secreted in units of time (min) . This parameter showed highly significant differences between the patients and controls . All patients with microbial keratitis, corrosive trauma, ocular trauma, herpetic infection, and other diseases showed highly significant elevation of plasmin flux compared with controls . The highest plasmin flux values (several hundredfold that of controls) were recorded in patients with severe corneal ulcers . Few patient samples showed some involvement of other proteases, which were not inhibited by aprotinin. J Bacteriol, 1994 Mar, 176(6), 1555 - 60 Sensing of aromatic compounds by the DmpR transcriptional activator of phenol-catabolizing Pseudomonas sp . strain CF600; Shingler V et al.; The dmp operon of the pVI150 catabolic plasmid of Pseudomonas sp . strain CF600 encodes the enzymes involved in the catabolism of phenol and methylphenols . The regulator of this dmp pathway, DmpR, is a member of the NtrC family of transcriptional activators and controls transcription of the dmp operon in response to aromatic effector compounds (V . Shingler, M . Bartilson, and T . Moore, J . Bacteriol . 175:1596-1604, 1993) . Using a lux gene fusion reporter system, in which the DmpR-regulated operon promoter controls the expression of luciferase activity, we have shown in the study reported here that DmpR is activated by, but responds differentially to, the presence of a wide range of aromatic compounds . In many microbial regulatory systems, including some members of the NtrC family, the response to environ