Kyobu Geka, 1996 Jan, 49(1), 53 - 6 {Reconstruction of chest wall defects with autogenous ribs grafts}; Kawamura M et al.; Three methods of chest wall reconstruction using autogenous rib grafts were reported . Fresh non-vascularized autogenous rib graft, vascularized autogenous ribs with muscle-flap, and pasteurized autogenous rib grafts were the materials used in these techniques . They are less convenient than those with artificial materials but afterwards physiologically more natural chest wall will be reconstructed . The third method (pasteurized rib graft) was applied to 22-year-old female with large recurrent desmoid tumor . Six resected ribs were heated in the saline at 60 degrees C for 30 min . and three of them were returned to the former position . Though tumor cells and bacteria are killed under this condition, these heated bone can be revascularized and replaced by normal bone as early as fresh non-vascularized rib graft. Infect Immun, 1996 Jan, 64(1), 50 - 4 Immunosuppressive factor from Actinobacillus actinomycetemcomitans down regulates cytokine production; Kurita-Ochiai T et al.; A cytoplasmic soluble fraction of Actinobacillus actinomycetemcomitans Y4 was isolated and characterized as suppressing mitogen-stimulated proliferation of and cytokine production by C3H/HeN mouse splenic T cells . This factor, designated suppressive factor 1 (SF1), was isolated from the supernatant of sonicated whole bacteria and purified by Q-Sepharose Fast Flow column chromatography, DEAE-Sepharose Fast Flow column chromatography, hydroxyapatite high-pressure liquid chromatography (HPLC), and Protein Pack 300 & 125 gel filtration HPLC . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that the purified SF1 migrated as a single band corresponding to a molecular mass of 14 kDa . This molecule was protease labile, heat resistant, and noncytotoxic . N'-terminal sequence analysis revealed no homology with any known peptides of periodontopathic bacteria or with any host-derived growth factors . Purified SF1 suppressed the proliferation of mouse splenic T cells which had been stimulated with concanavalin A, as well as suppressing the production of interleukin-2 (IL-2), gamma interferon, IL-4, and IL-5 from CD4+ T cells as 0.1 microgram/ml or more . These data suggest that SF1 produced by the periodontal pathogen A . actinomycetemcomitans functions as a virulence factor by down regulating T-cell proliferation and cytokine production at local defense sites. Infect Immun, 1996 Jan, 64(1), 197 - 208 Adherence, fibronectin binding, and induction of cytoskeleton reorganization in cultured human cells by Mycoplasma penetrans; Giron JA et al.; Mycoplasma penetrans adhered to cultured human cells, forming clusters that localized to specific areas of the host cell surface . Adherence and cluster formation were inhibited by anti-M . penetrans antibodies, suggesting the involvement of specific adhesin-receptor interactions . Ultrastructural studies showed that after 2 h of infection, mycoplasmas attach to and penetrate the host cell surface . M . penetrans bound selectively to immobilized fibronectin, an interaction which was not inhibited by a 70-kDa fragment containing a heparin-gelatin-binding domain of fibronectin, other matrix glycoproteins, or an RGD tripeptide, suggesting the recognition of other specific binding sites on the fibronectin molecule . A ca . 65-kDa fibronectin-binding protein of M . penetrans was eluted following Sepharose-fibronectin affinity chromatography . Confocal, light, and immunofluorescence microscopy demonstrated that the interaction of M . penetrans with target cells triggers a signal that causes recruitment of several cytoskeletal components, including tubulin and alpha-actinin, and aggregation of phosphorylated proteins . Detergent-soluble mycoplasma proteins with apparent molecular masses of 18, 28, 32, 36, 39, and 41 kDa selectively bound to glutaraldehyde-fixed HEp-2 cells . Our findings offer new insights into understanding the interaction of this human mycoplasma with host target cells. J Bacteriol, 1996 Jan, 178(2), 505 - 10 Coenzyme F390 synthetase from Methanobacterium thermoautotrophicum Marburg belongs to the superfamily of adenylate-forming enzymes; Vermeij P et al.; Depending on the reduction-oxidation state of the cell, some methanogenic bacteria synthesize or hydrolyze 8-hydroxyadenylylated coenzyme F420 (coenzyme F390) . These two reactions are catalyzed by coenzyme F390 synthetase and hydrolase, respectively . To gain more insight into the mechanism of the former reaction, coenzyme F390 synthetase from Methanobacterium thermoautotrophicum Marburg was purified 89-fold from cell extract to a specific activity of 0.75 mumol.min-1.mg of protein-1 . The monomeric enzyme consisted of a polypeptide with an apparent molecular mass of 41 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . ftsA, the gene encoding coenzyme F390 synthetase, was cloned and sequenced . It encoded a protein of 377 amino acids with a predicted M(r) of 43,280 . FtsA was found to be similar to domains found in the superfamily of peptide synthetases and adenylate-forming enzymes . FtsA was most similar to gramicidin S synthetase II (67% similarity in a 227-amino-acid region) and sigma-(L-alpha-aminoadipyl)-L-cysteine-D-valine synthetase (57% similarity in a 193-amino-acid region) . Coenzyme F390 synthetase, however, holds an exceptional position in the superfamily of adenylate-forming enzymes in that it does not activate a carboxyl group of an amino or hydroxy acid but an aromatic hydroxyl group of coenzyme F420. J Bacteriol, 1996 Jan, 178(1), 12 - 8 A global signal transduction system regulates aerobic and anaerobic CO2 fixation in Rhodobacter sphaeroides; Qian Y et al.; Complementation of a mutant of Rhodobacter sphaeroides defective in photosynthetic CO2 reduction led to the identification of a gene which encodes a protein that is related to a class of sensor kinases involved in bacterial signal transduction . The nucleotide sequence and deduced amino acid sequence led to the finding that the gene which complemented the mutant is the regB (prrB) gene, previously isolated from both R . sphaeroides and Rhodobacter capsulatus and shown to regulate the anaerobic expression of structural genes required for the synthesis of the reaction center and light-harvesting systems of these organisms . The current investigation indicates that in addition to its role in the regulation of photosystem biosynthesis, regB (prrB) of R . sphaeroides is intimately involved in the positive regulation of the cbbI and cbbII Calvin cycle CO2 fixation operons . In addition to regulating the expression of structural genes encoding enzymes of the primary pathway for CO2 fixation in R . sphaeroides, regB was also found to be required for the expression of a gene(s) important for the putative alternative CO2 fixation pathway(s) of this organism . A mutation in regB also blocked expression of structural genes of the cbb regulon in a strain of R . sphaeroides capable of aerobic CO2-dependent growth in the dark . It is thus apparent that regB is part of a two-component system and encodes a sensor kinase involved in the global regulation of both anoxygenic light-dependent- and oxygenic light-independent CO2 fixation as well as anoxygenic photosystem biosynthesis. Ann Otol Rhinol Laryngol, 1996 Jan, 105(1), 54 - 7 Comparative perilymph permeability of cephalosporins and its significance in the treatment and prevention of suppurative labyrinthitis; Sun AH et al.; Cephalosporins are nonototoxic antibiotics that provide excellent coverage for almost all bacteria that can cause suppurative labyrinthitis . In this study we performed comparative perilymph permeability determinations of the three cephalosporins that we deemed to have the most clinical potential in these varied situations . Perilymph pharmacokinetic profiles were established for ceftazidime, cefuroxime, and cefotaxime and its metabolite desacetylcefotaxime in 36 guinea pigs by using the technique of high-performance liquid chromatography . At 1, 2, 3, 4, and 6 hours after intravenous administration of the three cephalosporins at a dose of 100 mg/kg of body weight, ceftazidime consistently exhibited the highest perilymph concentration . Desacetylcefotaxime showed the next highest capacity for penetration into perilymph . Keeping in mind that the choice of drug for the treatment of suppurative labyrinthitis should be based foremost on culture and sensitivity studies, we consider ceftazidime to be the first-line agent for treatment and prevention of both meningogenic labyrinthitis and labyrinthitis complicating acute or chronic otitis media. J Am Coll Surg, 1996 Jan, 182(1), 7 - 11 Necrotizing soft tissue infections: obstacles in diagnosis; Lille ST et al.; BACKGROUND: This study was done to identify obstacles in the early diagnosis and treatment of necrotizing soft tissue infections . STUDY DESIGN: A ten-year retrospective case series was analyzed . RESULTS: Data from 29 patients were analyzed . Among patients undergoing early operation within 24 hours of admission (n = 17) there was one death (6 percent mortality rate); survivors averaged 2.9 operations per patient . By comparison, of patients with delayed operation (n = 12) three died (25 percent mortality rate) and there were 3.6 operations per patients . Positive fine-needle aspiration (FNA) of suspicious lesions, demonstrating either pus or bacteria by Gram's stain, led to early operation in 80 percent of patients tested . Patients with soft tissue gas on radiographs were more likely to undergo early operation (58 percent) . Delayed operation was more common in the absence of radiographic findings . All patients admitted to nonsurgical services had delayed operations . CONCLUSIONS: Suspected necrotizing soft tissue infections require prompt surgical evaluation and early operative exploration . Early operation with definitive surgical therapy initiated within 24 hours of admission is associated with decreased mortality rates . Negative FNA findings, nondiagnostic radiographs, and admission to a nonsurgical service correlate with delay in definitive operative intervention. Rev Environ Contam Toxicol, 1996, 145, 129 - 73 Atrazine retention and transport in soils; Ma L et al.; No pesticide has been studied as extensively as atrazine . The study of atrazine has contributed to our general understanding of the behavior of pesticides in soils . New knowledge and concepts were evaluated, such as atrazine adsorption kinetics, desorption hysteresis, and preferential flow . Corresponding conceptual models were also proposed to explain the behavior of atrazine in soils . Atrazine adsorption-desorption is the major process affecting atrazine behavior in soils and is mainly affected by organic matter and soil pH . Atrazine in soils is subject to biological and chemical degradations . Hydroxyatrazine, the chemical degradation product, is more strongly adsorbed to soil than atrazine . Deethylatrazine and deisopropylatrazine, the major biological degradation products, are more mobile than atrazine . Hydrolysis of atrazine is soil-surface catalyzed and favored by low soil pH . The overall dissipation rate of atrazine was found to be pseudo first-order . Two distinct and different processes are involved in atrazine movement: slow transport through the soil matrix and rapid movement through macropores . The first process is controlled by adsorption kinetics and degradation reactions and can be well explained by models based on chemical heterogeneity, such as the two-site models and second-order models . The second flow process results from preferential flow through large pores and can be explained by physical nonequilibrium models such as the mobile-immobile and two-flow domain models . Because both processes coexist in atrazine transport, coupling of physical and chemical nonequilibrium models is often necessary and has shown promise in atrazine transport modeling . However, more efforts are needed in estimating model parameters and in developing management-oriented models. Gene, 1995 Dec 29, 167(1-2), 279 - 83 A single amino-acid change between the antigenically different extracellular serine proteases V2 and B2 from Dichelobacter nodosus; Riffkin MC et al.; Dichelobacter nodosus (Dn), the causative organism of ovine footrot, secrets three distinct types of extracellular serine proteases which have been implicated in virulence . Southern analyses have shown that the proteases are encoded by three separate genes, and the genes encoding an acidic protease V5 and a basic protease have already been characterised from virulent Dn strain 198 . The gene encoding the third protease type, as represented by acidic protease V2, was isolated from an EcoRI-BamHI library of strain 198 genomic DNA by probing with a polymerase chain reaction (PCR) fragment generated with oligodeoxyribonucleotides based on protease V2 amino acid (aa) sequences . A further clone from an RsaI library was isolated to complete the 5' region of the gene to yield an ORF of 1803 bp encoding a protein precursor of 601 aa . The acidic protease V2 gene, aprV2, shows the same precursor structure as the bprV and aprV5 genes with 72% and 69% similarity at the nucleotide (nt) level and with 73% and 69% similarity at the aa level, respectively . As monoclonal antibodies consistently distinguish the virulent (V) and benign (B) forms of this protease, the gene encoding the acidic protease B2 from benign Dn strain 305 was isolated using the PCR and characterized to investigate the molecular basis for this difference in antigenicity . A 2-bp substitution in a single codon was identified which appeared to be responsible for a change of epitope. J Biol Chem, 1995 Dec 29, 270(52), 31244 - 8 Regulation of NF-kappa B through the nuclear processing of p105 (NF-kappa B1) in Epstein-Barr virus-immortalized B cell lines; Baldassarre F et al.; Transcription factors of the NF-kappa B/Rel family are retained in the cytoplasm as inactive complexes through association with I kappa B inhibitory proteins . Several NF-kappa B activators induce the proteolysis of I kappa B proteins, which results in the nuclear translocation and DNA binding of NF-kappa B complexes . Here, we report a novel mechanism of NF-kappa B regulation mediated by p105 (NF-kappa B1) precursor of p50 directly at the nuclear level . In Epstein-Barr virus-immortalized B cells, p105 was found in the nucleus, where it was complexed with p65 . In concomitance with NF-kappa B activation, mitomycin C induced the processing of p105 to p50 in the nucleus, while it did not affect the steady-state protein levels of I kappa B alpha and p105 in the cytoplasm . Differently, phorbol 12-myristate 13-acetate induced a significant proteolysis of both I kappa B alpha and p105 in the cytoplasm, while it did not affect the protein level of p105 in the nucleus . These results suggest that in Epstein-Barr virus-positive B cell lines the nuclear processing of p105 can contribute to NF-kappa B activation in response to specific signaling molecules, such as DNA-damaging agents. Transplantation, 1995 Dec 27, 60(12), 1504 - 10 Genetic control of the humoral immune response to xenografts . II . Monoclonal antibodies that cause rejection of heart xenografts are encoded by germline immunoglobulin genes; Borie DC et al.; The early phases of the rejection of xenografts exchanged between closely related species are dominated by a vigorous humoral immune response . We have recently used a linker-mediated polymerase chain reaction (LM-PCR) to generate Ig heavy and light chain-specific cDNA libraries to examine the Ig gene control of a prototypic IgM monoclonal antibody, HAR-1, that causes the hyperacute rejection of hamster xenografts . Recombinant clones from the library were screened directly from bacterial colonies by PCR and the nucleic acid sequences of the clones established . Our results demonstrate that the HAR-1 hybridoma is encoded by Ig VH and JH genes in a germline configuration . Comparison of the cDNA sequence for HAR-1 VH with the germline equivalent of this gene isolated from newborn LEW liver (provisionally designated VHHAR-1) showed that the two VH sequences share a nucleic acid identity of 99.3% . Similarly, the HAR-1 monoclonal uses a Ig JH gene that is 98.2% identical with the JH1 nucleic acid sequence available in the GeneBank . The use of Ig VH and JH genes in a germline configuration is similar to that seen with polyreactive natural antibodies to infectious agents and autoantibodies . These humoral responses are thought to be the result of the stimulation of a T cell-independent subset of B cells, the B-1a/B-1b subset, that is responsible for producing antibodies that serve as a primitive humoral (natural antibody) defense mechanism against infectious diseases . Our results suggest that the humoral component of the rejection of xenografts in the hamster-to-rat model may represent the stimulation of this type of B cell antibody response by xenogeneic target antigens that share antigenic epitopes with bacteria and other infectious agents. Nucleic Acids Res, 1995 Dec 25, 23(24), 5048 - 54 Specific binding of the replication protein of plasmid pPS10 to direct and inverted repeats is mediated by an HTH motif; Garcia de Viedma D et al.; The initiator protein of the plasmid pPS10, RepA, has a putative helix-turn-helix (HTH) motif at its C-terminal end . RepA dimers bind to an inverted repeat at the repA promoter (repAP) to autoregulate RepA synthesis . {D . Garcia de Viedma, et al . (1996) EMBO J . in press} . RepA monomers bind to four direct repeats at the origin of replication (oriV) to initiate pPS10 replication This report shows that randomly generated mutations in RepA, associated with defficiencies in autoregulation, map either at the putative HTH motif or in its vicinity . These mutant proteins do not promote pPS10 replication and are severely affected in binding to both the repAP and oriV regions in vitro . Revertants of a mutant that map in the vicinity of the HTH motif have been obtained and correspond to a second amino acid substitution far upstream of the motif . However, reversion of mutants that map in the helices of the motif occurs less frequently, at least by an order of magnitude . All these data indicate that the helices of the HTH motif play an essential role in specific RepA-DNA interactions, although additional regions also seem to be involved in DNA binding activity . Some mutations have slightly different effects in replication and autoregulation, suggesting that the role of the HTH motif in the interaction of RepA dimers or monomers with their respective DNA targets (IR or DR) is not the same. J Biol Chem, 1995 Dec 22, 270(51), 30453 - 7 Purification and characterization of a novel ADP-dependent glucokinase from the hyperthermophilic archaeon Pyrococcus furiosus; Kengen SW et al.; Pyrococcus furiosus uses a modified Embden-Meyerhof pathway during growth on poly- or disaccharides . Instead of the usual ATP-dependent glucokinase, this pathway involves a novel ADP-dependent (AMP-forming) glucokinase . The level of this enzyme and some other glycolytic enzymes appeared to be closely regulated by the substrate . Growth on cellobiose resulted in a high specific activity of 0.96 units mg-1, whereas on pyruvate a 10-fold lower activity was found . The ADP-dependent glucokinase was purified 1350-fold to homogeneity . The oxygen-stable enzyme had a molecular mass of 93 kDa and was composed of two identical subunits (47 kDa) . The glucokinase was highly specific for ADP, which could not be replaced by ATP, phosphoenolpyruvate, GDP, PPi, or polyphosphate . D-Glucose could be replaced only by 2-deoxy-D-glucose, albeit with a low efficiency . The Km values for D-glucose and ADP were 0.73 and 0.033 mM, respectively . An optimum temperature of 105 degrees C and a half-life of 220 min at 100 degrees C are in agreement with the requirements of this hyperthermophilic organism . The properties of the glucokinase are compared to those of less thermoactive gluco/hexokinases. Carbohydr Res, 1995 Dec 20, 278(2), 289 - 300 Synthesis of 2-(4-aminophenyl)ethyl 3-deoxy-5-O-(3,4,6-tri-O-beta-D- glucopyranosyl-alpha-D-glucopyranosyl)-alpha-D-manno-oct-2-ulopyrano sid onic acid, a highly branched pentasaccharide corresponding to structures found in lipopolysaccharides from Moraxella catarrhalis; Ekelof K et al.; Syntheses of the pentasaccharide 2-(4-aminophenyl)ethyl 3-deoxy-5-O-(3,4,6- tri-O-beta-D-glucopyranosyl-alpha-D-glucopyranosyl)-alpha-D-manno-oct-2- ulopyranosidonic acid and of the tetrasaccharide 3,4,6-tri-O-beta-D-glucopyranosyl-alpha-D-glucopyranoside, both as its methyl and 2-(4-trifluoro-acetamidophenyl)ethyl glycoside, are described . These oligosaccharides correspond to structures found in the lipopolysaccharide of Moraxella catarrhalis and were needed for biological experiments aimed at producing antibodies against the bacteria . The best way to introduce the glucopyranosyl groups into the 3-, 4-, and 6-positions of the branched target compounds was found to be a one-step reaction using a 3,4,6-triol as acceptor and 2,3,4,6-tetra-O-benzoyl-D-glucopyranosyl bromide as donor in a silver trifluoromethanesulfonate-promoted coupling . The spacer arm, necessary for the formation of immunoactive glycoconjugates, was introduced into the glucose moiety via a dimethyl(methylthio)sulfonium trifluoromethanesulfonate-promoted reaction using the ethyl thioglucoside as donor, whereas for Kdo, the acetylated glycal derivative, methyl 4,5,7,8-tetra-O-acetyl-2,6-anhydro-3-deoxy-D-manno-oct-2-enonate, was used as donor and phenylselenyl trifluoromethanesulfonate as a stereocontrolling promoter. Proc Natl Acad Sci U S A, 1995 Dec 19, 92(26), 12384 - 8 Characterization of the wild-type form of 4a-carbinolamine dehydratase and two naturally occurring mutants associated with hyperphenylalaninemia; Johnen G et al.; The characterization of 4a-carbinolamine dehydratase with the enzymatically synthesized natural substrate revealed non-Michaelis-Menten kinetics . A Hill coefficient of 1.8 indicates that the dehydratase exists as a multisubunit enzyme that shows cooperativity . A mild form of hyperphenylalaninemia with high 7-biopterin levels has been linked to mutations in the human 4a-carbinolamine dehydratase gene . We have now cloned and expressed two mutant forms of the protein based on a patient's DNA sequences . The kinetic parameters of the mutant C82R reveal a 60% decrease in Vmax but no change in Km (approximately 5 microM), suggesting that the cysteine residue is not involved in substrate binding . Its replacement by arginine possibly causes a conformational change in the active center . Like the wild-type enzyme, this mutant is heat stable and forms a tetramer . The susceptibility to proteolysis of C82R, however, is markedly increased in vitro compared with the wild-type protein . We have also observed a decrease in the expression levels of C82R protein in transfected mammalian cells, which could be due to proteolytic instability . The 18-amino acid-truncated mutant GLu-87--> termination could not be completely purified and characterized due to minute levels of expression and its extremely low solubility as a fusion protein . No dehydratase activity was detected in crude extracts from transformed bacteria or transfected mammalian cells . Considering the decrease in specific activity and stability of the mutants, we conclude that the patient probably has less than 10% residual dehydratase activity, which could be responsible for the mild hyperphenylalaninemia and the high 7-biopterin levels. Experientia, 1995 Dec 18, 51(12), 1175 - 88 Cell adhesion in the life cycle of Dictyostelium; Bozzaro S et al.; Three forms of cell adhesion determine the life cycle of Dictyostelium: i) adhesion of bacteria to the surface of the growing amoebae, as the prerequisite for phagocytosis; ii) cell-substrate adhesion, necessary for both locomotion of the amoebae and migration of the slug; iii) cell-cell adhesion, essential for transition from the unicellular to the multicellular stage . Intercellular adhesion has received the most attention, and fruitful approaches have been developed over the past 25 years to identify, purify and characterize cell adhesion molecules . The csA glycoprotein, in particular, which mediates adhesion during the aggregation stage, is one of the best defined cell adhesion molecules . The molecular components involved in phagocytosis and cell-substratum adhesion are less well understood, but the basis has been laid for a systematic investigation of both topics in the near future. Experientia, 1995 Dec 18, 51(12), 1124 - 34 PSF and CMF, autocrine factors that regulate gene expression during growth and early development of Dictyostelium; Clarke M et al.; Throughout growth and development, Dictyostelium cells secrete autocrine factors that accumulate in proportion to cell density . At sufficient concentration, these factors cause changes in gene expression . Vegetative Dictyostelium cells continuously secrete prestarvation factor (PSF) . The bacteria upon which the cells feed inhibit their response to PSF, allowing the cells to monitor their own density in relation to that of their food supply . At high PSF/bacteria ratios, which occur during late exponential growth, PSF induces the expression of several genes whose products are needed for cell aggregation . When the food supply has been depleted, PSF production declines, and a second density-sensing pathway is activated . Starving cells secrete conditioned medium factor (CMF), a glycoprotein of Mr 80 kDa that is essential for the development of differentiated cell types . Antisense mutagenesis has shown that cells lacking CMF cannot aggregate, and preliminary data suggest that CMF regulates cAMP signal transduction . Calculations indicate that a mechanism of simultaneously secreting and recognizing a signal molecule, as used by Dictyostelium to monitor cell density, could also be used to determine the total number of cells in a tissue. FEMS Microbiol Lett, 1995 Dec 15, 134(2-3), 279 - 85 Genomic heterogeneity in Chlorobium limicola: chromosomic and plasmidic differences among strains; Mendez-Alvarez S et al.; Chromosome analysis by pulsed-field gel electrophoresis shows a high level of genetic heterogeneity between the two subspecies of the green sulfur bacteria Chlorobium limicola analysed: C . limicola and C . limicola f . s . thiosulfatophilum . Currently, they are differentiated only by the ability to utilize thiosulfate as photosynthetic electron donor, and by their %G + C content (51% and 58.1%, respectively) . However, the capacity to utilize thiosulfate as photosynthetic electron donor does not appear to be a useful criterion to differentiate between some strains of this species, because this ability is encoded by plasmids that are different depending on the thiosulfatophilum strain analysed . In contrast, this study reveals that the comparison of chromosomal restriction patterns is very useful as an additional aid for the differentiation and identification of C . limicola strains. J Biol Chem, 1995 Dec 15, 270(50), 29640 - 3 Human ADP-ribosylation factor-activated phosphatidylcholine-specific phospholipase D defines a new and highly conserved gene family; Hammond SM et al.; Activation of phosphatidylcholine-specific phospholipase D (PLD) has been implicated as a critical step in numerous cellular pathways, including signal transduction, membrane trafficking, and the regulation of mitosis . We report here the identification of the first human PLD cDNA, which defines a new and highly conserved gene family . Characterization of recombinant human PLD1 reveals that it is membrane-associated, selective for phosphatidylcholine, stimulated by phosphatidylinositol 4,5-bisphosphate, activated by the monomeric G-protein ADP-ribosylation factor-1, and inhibited by oleate . PLD1 likely encodes the gene product responsible for the most widely studied endogenous PLD activity. J Immunol, 1995 Dec 15, 155(12), 5760 - 8 Clearance pathways of soluble immune complexes in the pig . Insights into the adaptive nature of antigen clearance in humans; Davies KA et al.; Efficient delivery of immune complexes (ICs) to the mononuclear phagocytic system, and subsequent IC processing, may prevent their potentially harmful effects in other tissues and may also be important in the development of humoral immune responses . In mice, rabbits, and primates, the liver and spleen are the main sites of IC clearance . It has been demonstrated previously that the pulmonary capillaries in the pig are lined with macrophages and that certain particulates, including bacteria, localize to this organ . In this study, we used gamma scintigraphy to explore the sites and kinetics of clearance of soluble IC comprising 123I-labeled hepatitis B surface Ag (HBsAg):porcine anti-HBsAg in the Large White pig . At t = 10 min after i.v . injection, 43 +/- 5% (mean +/- SE) IC localized in the lungs, and 36 +/- 6% counts in the liver . At t = 85 min, values were: lungs, 15 +/- 4% and liver, 29 +/- 2% . Findings were similar following intraarterial injection . Complement depletion resulted in more rapid initial IC clearance (t1/2 = 5 min), reduced lung uptake (23 +/- 3% at 10 min), and impaired IC catabolism . In normal animals, 5 to 7% injected IC bound to PBMCs, but no E binding was seen . A fall in PBMC numbers (46 to 59% of baseline), was observed following IC injection . These findings contrast with our previous observations using analogous IC in humans, in which we did not observe any change in peripheral blood leukocyte counts consequent upon complex processing, suggesting that in humans, Es may function as a buffering system for complement-bearing IC in the circulation, preventing their interaction with leukocytes bearing complement and FcR, and the potential activation of these cells. J Am Vet Med Assoc, 1995 Dec 15, 207(12), 1618 - 21 Epizootic of Mycobacterium bovis in a zoologic park; Stetter MD et al.; An epizootic of Mycobacterium bovis in a zoologic park resulted in the death of 4 southern white rhinoceroses and 2 colobus monkeys . Zoo personnel were detected that had positive intradermal tuberculin skin test results after exposure to mycobacterial-infected animals . On the basis of DNA fingerprinting, all 3 mycobacterial isolates (from 1 rhinoceros and 2 monkeys) were determined to be genetically similar and probably originated from the same source . The 3 animals (1 rhinoceros and 2 colobus monkeys) that had confirmed infections lived in separate, but adjacent, areas . Aerosolization of bacteria during routine cleaning was believed to have contributed to the unusual distance between infected animals . Tuberculosis has reemerged as a major disease problem in human and veterinary medicine. Biochemistry, 1995 Dec 12, 34(49), 16004 - 12 Tyrosine 147 of cytochrome b is required for efficient electron transfer at the ubihydroquinone oxidase site (Qo) of the cytochrome bc1 complex; Saribas AS et al.; In Rhodobacter capsulatus, tyrosine (Y) 147 is a highly conserved residue of the cyt b subunit of the bc1 complex . It is located in the vicinity of residues altered in spontaneous inhibitor resistant mutants that affect the ubihydroquinone oxidase (Qo) site of this enzyme . In this work, Y147 was substituted with phenylalanine (F), valine (V), serine (S), and alanine (A) using site-directed mutagenesis in an effort to investigate its specific role in the Qo site . Of the four mutants obtained, Y147S and Y147A exhibited very low ubihydroquinone:cyt c reductase activities and were unable to support photosynthetic growth (Ps) while Y147F and Y147V were Ps+ . In all mutants, no changes in the redox midpoint potentials (Em7) of the cyt bH and cyt bL, the occupancy of the Qo site by Q/QH2, and the flash-induced reverse electron transfer kinetics from Qi to cyt bH were observed . On the other hand, rates of electron transfer from Qo to cyt bH were mildly reduced (2-3-fold) in Y147F and V but dramatically decreased (about 20-fold) in Y147A and S, localizing the defect to the Qo site . Thus, Y147A and S are members of a novel class of Qo site mutants that affect the Qo site catalysis without perturbing the accessibility or binding of the substrate . Additional insight to the role of Y147 on ubihydroquinone oxidation was gained by analyzing the Ps+ revertants of these mutants . Two pseudorevertants contained a second mutation {isoleucine (I) or valine (V)} at the highly conserved M154 position, six residues away from Y147.(ABSTRACT TRUNCATED AT 250 WORDS) J Mol Biol, 1995 Dec 8, 254(4), 595 - 607 Mutations in the gene encoding the 34 kDa subunit of yeast replication protein A cause defective S phase progression; Santocanale C et al.; The in vivo function of the 34 kDa subunit of yeast replication protein A (RPA), encoded by the RFA2 gene, has been studied by analyzing the effect of Rpa34 depletion and by producing and characterizing rfa2 temperature-sensitive mutants . We show that unbalanced stoichiometry of the RPA subunits does not affect cell growth and cell cycle progression until the level of Rpa34 becomes rate-limiting, at which point cells arrest with a late S/G2 DNA content . Rpa34 is involved in DNA replication in vivo, since rfa2 ts mutants are defective in S phase progression and ARS plasmid stability, and rfa2 pol1 double mutants are non-viable . Moreover, when shifted to the restrictive temperature, about 50% of the rfa2 mutant cells rapidly die while traversing the S phase and the surviving cells arrest in late S/G2 at the RAD9 checkpoint . Finally, rfa2 mutant cells have a mutator and hyper-recombination phenotype and are more sensitive to hydroxyurea and methyl-methane-sulfonate than wild-type cells. MMWR Morb Mortal Wkly Rep, 1995 Dec 8, 44(48), 892 - 3, 899-900 Unexplained severe illness possibly associated with consumption of Kombucha tea--Iowa, 1995; Outbreak of hepatitis A in a college traced to contaminated water reservoir in cafeteria; Division of Epidemiology, Ministry of Public Health, Nonthaburi, ThailandA sharp but short outbreak of hepatitis A occurred in a college during September and October 1992 . The epidemic pattern suggested a common source . The attack rate of clinically recognizable hepatitis A was 8% all cases were HAV IgM positive . Among 31 students with minor symptoms but without jaundice 8 (26%) were also HAV IgM positive, as were 8 (10%) of 77 totally asymptomatic students tested . A case control study of eating and drinking habits of the students showed no other significant differences other than that 45 of 56 cases and 18 of 34 controls interviewed had filled their water glasses by dipping them in a overflow water reservoir . This gives an odds ratio of 3.8 . The reservoir was heavily contaminated with coliform bacteria and the residual chlorine was at lower than standard concentration, whereas other water resources were clean . It is suggested that the reservoir had been contaminated with hepatitis A virus by somebody with fecally contaminated hands a couple of weeks prior to the beginning of the outbreak. Cell Growth Differ, 1995 Dec, 6(12), 1495 - 503 The LAZ3/BCL6 oncogene encodes a sequence-specific transcriptional inhibitor: a novel function for the BTB/POZ domain as an autonomous repressing domain; Deweindt C et al.; Rearrangements and mutations of the LAZ3/BCL6 gene are the most frequent events associated with diffuse large-cell lymphoma, a particular class of non-Hodgkin's lymphomas . This gene encodes a putative regulatory protein with six COOH-terminal Kruppel-like zinc fingers and a NH2-terminal hydrophobic region, the so-called BTB/POZ domain, which mediates homo- as well as heterotypic interactions in other related proteins . Recently, a consensus binding sequence has been defined using the isolated LAZ3/BCL6 zinc finger region produced in bacteria . To understand the normal and oncogenic functions of LAZ3/BCL6, we examined its properties as a transcription factor . We thus demonstrated that its full-length product binds to the same consensus sequence, although the BTB/POZ domain decreases this activity, at least in vitro . In transient transfection experiments, the LAZ3/BCL6 protein exerts a repressive effect, both as a wild-type protein on its own target sequence and as a GAL-4 fusion protein . Furthermore, our results indicate that the BTB/POZ domain plays a prominent role in the mediation of this activity . Indeed, on the LAZ3/BCL6 cognate sequence, deletion of the BTB/POZ domain diminishes the repressive function . Conversely, as a GAL-4 chimera, the isolated LAZ3/BCL6 BTB/POZ domain appears nearly as efficient as the entire protein at inducing transcriptional repression . Taken together, these findings demonstrate that the LAZ3/BCL6 is a sequence-specific transcriptional repressor and point to a novel function for the BTB/POZ region, at least in LAZ3/BCL6, as an autonomous transcriptional inhibitory domain. Differentiation, 1995 Dec, 59(5), 289 - 97 Cell-density-dependent repression of discoidin in Dictyostelium discoideum; Wetterauer BW et al.; When Dictyostelium discoideum cells are grown on bacteria, their natural food source, the discoidin genes are induced by cell-density-sensing factors before the food supply is exhausted {11, 18}, and expression increases continuously thereafter . This regulation pattern is changed when cells are grown in axenic medium: the discoidins are induced at a considerably lower cell density and are no longer expressed in stationary phase {13} . We have investigated this phenomenon further and show that repression begins when cells are still in exponential growth . It occurs at the level of transcription and involves an element of the discoidin I gamma promoter for which no function has previously been described . Since the effect of high cell density can be mimicked by conditioned medium, it appears that the repression is due to an extracellular signal . This signal is neither ammonia, nor folate, nor cAMP, the known repressors of discoidin expression. Zentralbl Bakteriol, 1995 Dec, 283(2), 145 - 53 Diagnosis of catheter-related infections; Geiss HK; Catheter-related infections (CRI) are a major cause of febrile episodes in hospitalized patients . Additionally, approximately 40% of primary infections in intensive care patients are directly related to central venous catheters . Despite the clinical significance of CRI diagnostic procedures are still under debate . Clinical diagnosis which includes systemic signs of infection and suppuration at the catheter entry site is altogether a rare event . Therefore, most cases are still diagnosed by laboratory methods . Although the semiquantitative roll-plate technique is widely used and frequently regarded as gold standard, the disadvantages of a post-hoc diagnosis are obvious . In-situ techniques which leave the suspected catheter in place include differential blood cultures, skin and hub cultures and a new method of microscopic screening of blood drawn through the inflicted catheter . However, until now the true value of all these methods still lack unanimous acceptance . Further research is necessary to close the gap between clinical expectations and laboratory results. Mol Microbiol, 1995 Dec, 18(5), 903 - 12 Control of P1 plasmid replication by iterons; Abeles AL et al.; The incA locus of plasmid P1 controls plasmid copy number by inhibiting the replication origin, oriR . Both loci contain repeat sequences (iterons) that bind the P1 RepA protein . Regulation appears to occur by contact of incA and oriR loci of daughter plasmids mediated by RepA-bound iterons . Synthetic incA iteron arrays were constructed with altered numbers, sequences or spacing of iterons . Using these in in vitro and in vivo assays, we examined two models: (i) that the origin and incA loci form a stable 1:1 complex in which multiple iterons of each locus are paired with those of the other, and (ii) that individual incA iterons act as freely diffusing nucleoprotein units that contact origin iterons in a random and dynamic fashion . The data presented here strongly favour the latter case . The origin, with its five iterons, acts as a target but not as an effector of regulation . We present a model for replication control based on random, dynamic contacts between incA iterons and the origin . This system would display randomness with respect to choice of templates and timing of initiation if multiple replicon copies were present, but would tend to act in a machine-like fashion in concert with the cell cycle if just two copies were present in a dividing cell. Nihon Kyobu Shikkan Gakkai Zasshi, 1995 Dec, 33(12), 1392 - 1400 {Effect of clarithromycin on symptoms and mucociliary transport in patients with sino-bronchial syndrome}; Nishi K et al.; The effect of clarithromycin on symptoms and on mucociliary transport (as assessed by the saccharin test) were studied in 32 patients with sino-bronchial syndrome . Before treatment with clarithromycin, the nasal clearance time was significantly longer in these patients (70.3 +/- 64.7 min, mean +/- SD) than in control subjects (11.9 +/- 5.3 min, p < 0.001) . By the end of 4 weeks of treatment with oral clarithromycin (400 mg/day), nasal clearance time in the patients had improved significantly (30.4 +/- 39.5 min, p < 0.001) . Before clarithromycin therapy, bacteria were found in cultures of sputum from 15 patients . After clarithromycin therapy, bacteria were found in cultures of sputum from only 3 of those 15 patients . Cough frequency, volume of sputum, and dyspnea on exertion were significantly improved by clarithromycin therapy . These findings suggest that mucociliary transport is abnormal in patients with sino-bronchial syndrome, and that clarithromycin can be clinically useful in these patients. Trends Microbiol, 1995 Dec, 3(12), 469 - 74 Vaccines for gonorrhea: where are we on the curve? Blake MS, Wetzler LM. Human antibodies that bind the gonococcal outer membrane modulate gonorrheal transmission and disease . The effects of antibody binding can favor either the host or the bacteria, and depend on the antigen involved . An effective gonococcal vaccine is feasible, but only by the careful selection and formulation of gonococcal antigens that elicit only host-protective antibodies. Singapore Med J, 1995 Dec, 36(6), 619 - 20 Prolonged treatment with omeprazole does not improve the eradication rate of Helicobacter pylori infection--a short report {corrected}; Goh KL et al.; Omeprazole has been shown to have a suppressive effect on Helicobacter pylori . The aim of this study was to determine if prolonged treatment with omeprazole would result in a higher eradication rate than short course treatment . Twenty patients with endoscopy proven duodenal ulcers and unequivocal evidence of Helicobacter pylori (HP) infection based on culture, histology, urease test and Gram's stain of a fresh tissue smear were treated with omeprazole 40 mg om for 2-4 weeks . Following ulcer healing, patients received either maintenance omeprazole 20 mg om or placebo for up to one year . All 20 patients had healed ulcers following a 2-4 week course of omeprazole 40 mg om. . All were negative for HP at the end of treatment . Thirteen patients received short course therapy with omeprazole only, followed by placebo . On follow-up endoscopy at 3 months, only one of 13 (7.7%) had eradicated the bacteria . Seven patients received maintenance treatment with omeprazole 20mg om for one year . Following completion of treatment, patients were followed up at 1, 3 and 6 months . Only one of 7 (14.3%) patients had eradicated the infection on long term follow-up . The eradication rates of HP with both short and long course omeprazole monotherapy were low. J Hepatol, 1995 Dec, 23(6), 727 - 33 Reticuloendothelial system function in acute liver injury induced by D-galactosamine; Kasravi FB et al.; AIMS/METHODS: Reticuloendothelial system function, as assessed by clearance of radiolabelled bacteria, was evaluated in acute liver injury induced by D-galactosamine in rats, and compared with that after 70% liver resection model . RESULTS: Reticuloendothelial system function was significantly impaired in both instances, but the extent and the pattern of reticuloendothelial system impairment differed in the two models . While the elimination rate of the radiolabelled bacteria (k-value) decreased in both the liver resection and D-galactosamine groups (19% and 52%, respectively), the corrected phagocytic index (alpha) increased in 70% liver resection (247%), indicatine increased activity among the remaining reticuloendothelial system cells of the liver . Estimation of subserosal organ blood flow showed decreased flow to the cecum and distal small intestine (correction of intesting) in both groups, whereas it was significantly increased (477%) in the remaining parts of the liver in the liver resection group . CONCLUSIONS: These findings show that reticuloendothelial system activity is deranged in both these groups, which may explain the increased occurrence of bacterial complications observed in corresponding clinical conditions. Clin Infect Dis, 1995 Dec, 21(6), 1474 - 6 Vertebral osteomyelitis due to Roseomonas species: case report and review of the evaluation of vertebral osteomyelitis; Nahass RG et al.; We report what we believe is the first case of vertebral osteomyelitis caused by Roseomonas species . The diagnosis of vertebral osteomyelitis can be difficult . The case illustrates the importance of the establishment of an etiologic diagnosis in vertebral osteomyelitis . The features of Roseomonas species and the evaluation of cases of vertebral osteomyelitis are reviewed. Curr Opin Struct Biol, 1995 Dec, 5(6), 758 - 66 Di-iron-carboxylate proteins; Nordlund P et al.; Di-iron centers bridged by carboxylate residues and oxide/hydroxide groups have so far been seen in four classes of proteins involved in dioxygen chemistry or phosphoryl transfer reactions . The dinuclear iron centers in these proteins are coordinated by histidines and additional carboxylate ligands . Recent structural data on some of these enzymes, combined with spectroscopic and kinetic data, can now serve as a base for detailed mechanistic suggestions . The di-iron sites in the major class of hydroxylase-oxidase enzymes, which contains ribonucleotide reductase and methane monooxygenase, show significant flexibility in the geometry of their coordination of three or more carboxylate groups . This flexibility, combined with a relatively low coordination number, and a buried environment suitable for reactive oxygen chemistry, explains their efficient harnessing of the oxidation power of molecular oxygen. Vet Microbiol, 1995 Dec, 47(3-4), 245 - 56 Chlamydia psittaci in turkeys: pathogenesis of infections in avian serovars A, B and D; Vanrompay D et al.; At 7 days of age, 4 groups, each of twenty specific pathogen free turkeys kept in isolation units were inoculated by aerosol with the Texas Turkey strain (avian Chlamydia psittaci serovar D), strain 92/1293 (avian Chlamydia psittaci serovar D), strain 84/55 (avian Chlamydia psittaci serovar A) or strain 89/1326 (avian Chlamydia psittaci serovar B) . A fifth group of 4 specific pathogen free turkeys were sham inoculated controls . At daily intervals for 10 days and then twice weekly up to 34 days post infection, one bird in each group was killed and the target tissues and cells for replication and the sequence of events of serovar A, B and D infections was examined . In these turkeys, the primary site of replication was the respiratory tract . Chlamydial replication could be detected in the respiratory tract on day 1 post inoculation (p.i.) for group A, on day 3 p.i . for group B and on day 1 to 2 p.i . for groups D1 and D2 . Subsequently, there was chlamydaemia and localisation in the digestive tract, in one or more parenchymatous organs, in the pericardium and in the conjunctivae . Specific immunoperoxidase staining revealed chamydiae in these organs in epithelial cells and in monomorphonuclear cells in all infected groups . The monomorphonuclear cells were identified as macrophages by double immunofluorescence staining . Chlamydiae were present in the same tissues for serovars A and D, but could not be demonstrated in proventriculus, duodenum, pancreas, ovaries and testes for serovar B . Furthermore, the intensity of replication was similar for all serovars . However, for serovar B in comparison with the other serovars, the bacteria appeared in most tissues 1 to 6 days later and the maximal replication in these tissues occurred 3 to 4 days later. Vet Immunol Immunopathol, 1995 Dec, 49(3), 229 - 39 Effect of passively administered immunoglobulin G on the colonization and clearance of Bordetella avium in turkeys; Suresh P et al.; This study was conducted to detect the effect of parenterally administered immunoglobulin isotype G (IgG) on the colonization and clearance of Bordetella avium at the tracheal surface in young turkeys . In two separate experiments, 3-week-old turkeys were infected with B . avium either after or before IgG administration . Comparisons were made between a control group which received an irrelevant IgG (specific for keyhole limpet hemocyanin {KLH}) and the experimental group which received a B . avium-specific IgG . When given before the bacteria, IgG reduced the numbers of colony-forming units (CFUs) in the trachea . As a supplement to non-specific respiratory defense mechanisms, B . avium-specific IgG also appears to inhibit colonization of the tracheal mucosa . In a second experiment designed to study the role of IgG in bacterial clearance, administration of B . avium-specific IgG after bacterial inoculation significantly reduced the number of CFUs on the tracheal surface . These studies support the role of B . avium-specific IgG in resistance to and recovery from B . avium infection. Ann Trop Med Parasitol, 1995 Dec, 89 Suppl 1, 83 - 8 Vaccines against leishmaniasis; Modabber F; Unlike some other parasites, Leishmania can be grown in cell-free media with ease . This simple cultivation and the use of killed parasites as skin-test antigens (leishmanin) for diagnosis in humans during the past several decades have prompted scientists to try using the killed parasites, with or without adjuvant, as vaccines or for immunotherapy . In addition, different recombinant molecules, either parasite fractions or genetically engineered organisms (i.e . Leishmania made avirulent by removing specific genes, or bacteria carrying and expressing leishmanial genes), are being investigated as potential future vaccines against leishmaniasis . The 'first-generation' vaccines, composed of killed parasites with or without adjuvant, have been derived using an empirical approach . The 'second-generation' vaccines have been genetically constructed, using a more rational approach . At present, the first-generation vaccines are at various stages of Phase I (safety), II (reactivity) or III (efficacy) trials in humans . Results are expected in 1-2 years . The second-generation vaccines are, however, only in a preclinical state and are not expected to reach clinical trials for at least 3 years . The Special Programme for Research and Training in Tropical Diseases (TDR) is actively involved in most clinical trials of the first-generation vaccines and supports many of the second-generation candidates . In the present article, the advantages and disadvantages of each approach to vaccine development are discussed and the progress being made is briefly reviewed. Eur Heart J, 1995 Dec, 16 Suppl O, 36 - 41 The epidemiology of infectious myocarditis, lymphocytic myocarditis and dilated cardiomyopathy; Friman G et al.; Infectious myocarditis is a common condition which often passes unrecognized, and the true incidence is thus unknown . Lymphocytic myocarditis has been recorded in 1.06% of 12,747 unselected routine autopsies performed over a 10-year period . Dilated cardiomyopathy (DCM) has an estimated frequency of 7.5-10% per 100,000 inhabitants per year . Overall, the enteroviruses, and particularly the Coxsackie-B viruses, predominate among viruses as the cause of myocarditis . As new molecular biological techniques have become available, the cytomegaloviruses (CMV) seem to have emerged as a more common cause of myocarditis than was previously recognized . Among the bacterial myocarditides, diphtheric myocarditis has become a serious threat in Russia and adjacent states during the 1990s . Among newly identified bacteria, Borrelia burgdorferi infection is accompanied by cardiac involvement in 1-8% of cases, where myocarditis with conduction disturbances is the most prominent feature . Chlamydia pneumoniae may be associated with myocarditis and sudden unexpected death . In AIDS, myocarditis with variable aetiology occurs in up to 50% of patients, although asymptomatic in most cases . In lymphocytic myocarditis and DCM, enteroviral-specific nucleotide sequences have been detected in about 30% of patients, and CMV-specific nucleotide sequences in 14% . Borrelia burgdorferi may occasionally be implicated in DCM . In this contribution we focus also on sudden unexpected death (SUD) in young athletes, since, in Sweden, an increased frequency of SUD has recently been observed in young orienteers and myocarditis was a common feature. Eur J Clin Microbiol Infect Dis, 1995 Dec, 14(12), 1070 - 5 Role of immunoglobulin G subclasses in Q fever; Camacho MT et al.; The progression of Q fever to either acute or chronic disease has been attributed both to biological characteristics of the bacteria and to the host immune response . In order to determine whether a specific immunoglobulin G (IgG) subclass distribution could play a diagnostic or prognostic role in Q fever, IgG subclass levels were measured in patients with acute or chronic disease . It was observed that (i) IgG1 and IgG3 levels were elevated in patients with chronic Q fever compared to patients with acute disease or normal controls; (ii) variations over time reflected inverse complementary relationships of subclass levels, such as between IgG1 and IgG3 compared with IgG2 and IgG4, or an inverse relationship between IgG1 and IgG2; (iii) variations in IgG2 and IgG3 total subclass levels during follow-up of patients with chronic Q fever showed a decrease in IgG2 with a concomitant increase in IgG3 two years from disease onset . These findings indicate that measurements of IgG subclasses may be a simple, additional tool useful in the diagnosis of Q fever . This data raises the question of an unusual immunoregulatory mechanism in Q fever that is implicated in the presentation of the clinical disease. Int J Lepr Other Mycobact Dis, 1995 Dec, 63(4), 518 - 28 CD4+ T-cell responses to recombinant hsp65 and hsp18 of M . leprae and their trypsin-digested fragments in leprosy: diversity in HLA-DR restriction; Mitra DK et al.; Mycobacterium leprae heat-shock proteins hsp65 and hsp18 have received immense attention as major T-cell target antigens in leprosy . Both of these hsps and their tryptic fragments were characterized for their ability to stimulate CD4+ T cells derived from polar leprosy cases and healthy contacts . The optimal digestion of hsps with trypsin yielded four fragments of hsp65--TDB65-1 (24 kDa), TDB65-2 (18 kDa), TDB65-3 (17 kDa), TDB65-4 (14 kDa)-- and three of hsp18--TDB18-1 (10 kDa), TDB18-2 (5 kDa), TDB18-3 (3 kDa) . While all of these tryptic fragments and undigested hsps triggered CD4+ T cells from tuberculoid (TT) leprosy patients and healthy contacts (SI > 2), only two fragments--TDB65-2 and TDB18-3--were found to be stimulatory in anergic lepromatous (LL) leprosy patients (SI = 5.27 and 3.0, respectively) . Blocking studies using allele-specific anti-DR monoclonal antibodies revealed multiple HLA-Dr restriction, with DR2 providing the strongest restriction in both TT as well as LL leprosy . These findings indicate that M . leprae hsps and their trypsin-digested fragments are promiscuous and recognizable in the context of diverse HLA alleles, of which DR2 is the most efficient restriction element . The 18-kDa fragment of hsp65 and the 3-kDa fragment of hsp18 are the most versatile fragments that could elicit in vitro proliferation in both polar forms of leprosy. Lepr Rev, 1995 Dec, 66(4), 287 - 95 Extended studies on the viability of Mycobacterium leprae outside the human body; Desikan KV et al.; Very little is known in leprosy regarding the transmission of the infection from the source to the susceptible host . One of the important factors which governs the transmission of the disease is the viability of Mycobacterium leprae outside the human body . In this study M . leprae obtained from untreated patients have been subjected to several adverse conditions . Their viability was verified by their multiplication in the footpads of normal mice . After drying in the shade the organisms were viable up to 5 months . On wet soil, they remained alive for 46 days . Kept in saline at room temperature, the organisms lived for 60 days . Surprisingly on exposure to direct sunlight for 3 hours a day the bacteria survived for 7 days . On refrigeration at 4 degrees C, the bacteria could be preserved for 60 days . On the other hand, keeping at -70 degrees C, the bacteria could be maintained in a living condition for only 28 days . On exposure to antiseptics like Savlon (R) and alcohol, the bacteria were rapidly killed . These results indicate the survival outside the human body of M . leprae under different environmental conditions in India where the disease is endemic . Transmission of infection by indirect contact and occurrence of new cases in the absences of any known source, are consistent with M . leprae being viable outside the human body for varying periods of time . The findings could also be pointers to understand the epidemiology of leprosy. Plant Mol Biol, 1995 Dec, 29(6), 1223 - 33 Molecular characterization of glyoxalase-I from a higher plant; upregulation by stress; Espartero J et al.; A cDNA, GLX1, encoding glyoxalase-I was isolated by differential screening of salt-induced genes in tomato . Glyoxalases-I and -II are ubiquitous enzymes whose functions are not clearly understood . They may serve to detoxify methylglyoxal produced from triosephosphates in all cells . The protein encoded by GLX1 shared 49.4% and 58.5% identity with glyoxalase-I isolated from bacteria and human, respectively . Furthermore, yeast cells expressing GLX1 showed a glyoxalase-I specific activity 20-fold higher than non-transformed cells . Both GLX1 mRNA and glyoxalase-I polypeptide levels increased 2- to 3-fold in roots, stems and leaves of plants treated with either NaCl, mannitol, or abscisic acid . Immunohistochemical localization indicated that glyoxalase-I was expressed in all cell types, with preferential accumulation in phloem sieve elements . This expression pattern was not appreciably altered by salt-stress . We suggest that the increased expression of glyoxalase-I may be linked to a higher demand for ATP generation and to enhanced glycolysis in salt-stressed plants. N Y State Dent J, 1995 Dec, 61(10), 22 - 8 Doctor, would you drink water from your dental unit? Prevost AP, Robert M, Charland R, Barbeau J. Contamination of dental unit water lines is not new to dentistry, but this problem takes on a new dimension when considering immuno-deficient patients and existing infection-control measures . This study identifies the bacteria involved in the contamination process, estimates the contamination levels and reviews the methods that may be used to control the contamination. J Endod, 1995 Dec, 21(12), 613 - 6 Anaerobic tissue-dissolving abilities of calcium hydroxide and sodium hypochlorite; Yang SF et al.; Closed root canals likely have an oxygen-free environment; most bacteria in canals are anaerobic . These bacteria and other debris are difficult to remove . Unknown is tissue dissolution with chemicals under these anaerobic conditions . This study evaluated and compared dissolving properties of calcium hydroxide (Ca(OH)2) and sodium hypochlorite (NaOCl) on bovine pulp tissue in aerobic and anaerobic environments . Sixty bovine pulp specimens were dried, then randomly divided into six groups . Groups A and B were immersed in Ca(OH)2 + water solution, whereas group C and D were in 2.5% NaOCl . Groups E and F (controls) specimens were placed in distilled water . Groups A, C, and E were incubated anaerobically, and groups B, D, and F were incubated under regular atmospheric conditions, all for 7 days . Percentages of weight loss were compared between groups . Results showed the following: (a) both chemicals partially dissolved pulp tissue, (b) anaerobic environment did not alter tissue-dissolving properties of Ca(OH)2 or NaOCl, and (c) Ca(OH)2 and NaOCl were equal and more effective than water. Trends Biotechnol, 1995 Dec, 13(12), 497 - 500 Discovering the intelligence in molecular biology; Uberbacher E; The Third International Conference on Intelligent Systems in Molecular Biology was truly an outstanding event . Computational methods in molecular biology have reached a new level of maturity and utility, resulting in many high-impact applications . The success of this meeting bodes well for the rapid and continuing development of computational methods, intelligent systems and information-based approaches for the biosciences . The basic technology, originally most often applied to 'feasibility' problems, is now dealing effectively with the most difficult real-world problems . Significant progress has been made in understanding protein-structure information, structural classification, and how functional information and the relevant features of active-site geometry can be gleaned from structures by automated computational approaches . The value and limits of homology-based methods, and the ability to classify proteins by structure in the absence of homology, have reached a new level of sophistication . New methods for covariation analysis in the folding of large structures such as RNAs have shown remarkably good results, indicating the long-term potential to understand very complicated molecules and multimolecular complexes using computational means . Novel methods, such as HMMs, context-free grammars and the uses of mutual information theory, have taken center stage as highly valuable tools in our quest to represent and characterize biological information . A focus on creative uses of intelligent systems technologies and the trend toward biological application will undoubtedly continue and grow at the 1996 ISMB meeting in St Louis. Biomaterials, 1995 Dec, 16(18), 1395 - 400 Physico-mechanical properties of poly (epsilon-caprolactone) for the construction of rumino-reticulum devices for grazing animals; Vandamme TF et al.; The solid-state degradation of poly(epsilon-caprolactone) in the rumen of fistulated cattle was investigated . The degradation process was studied by measurement of changes in weight loss, crystallinity, Young's modulus, molecular weight by size exclusion chromatography and by intrinsic viscosity . In vitro degradation studies were conducted at 39 degrees C in aqueous solutions with a pH and ionic strength as near as possible to those encountered in vivo . Such studies demonstrated that the poly (epsilon-caprolactone) degraded more rapidly in vivo than in vitro . In vivo, chain scission is associated with an increase in crystallinity . The faster degradation in vivo was attributed to fatty acids and bacteria that are present in the rumen, the first portion of the stomach of the grazing animals. Exp Mycol, 1995 Dec, 19(4), 314 - 9 Osmotic effects on the polyamine pathway of Neurospora crassa; Davis RH et al.; In bacteria, mammals, and certain plants, the induction of the polyamine synthetic enzyme, ornithine decarboxylase (ODC), and the accumulation of its product, putrescine, follows osmotic manipulations of cells . In at least some of these cases, this response is indispensable for survival . We wished to determine whether the polyamine pathway of Neurospora crassa was regulated in response to hyper- or hypoosmotic conditions . Unlike ODC of most other classes of organisms, the N . crassa enzyme and the accumulation of putrescine appears to be relatively indifferent to these conditions, either during sudden transitions or in steady-state . We conclude that other mechanisms of osmotic adjustment or tolerance have evolved in N . crassa and perhaps other fungi that obviate the need for putrescine accumulation. Immunology, 1995 Dec, 86(4), 519 - 24 Protection against tuberculosis by bone marrow cells expressing mycobacterial hsp65; Silva CL et al.; Although mice acquire only a slight degree of protection against tuberculosis by immunization with Mycobacterium leprae (M . leprae) hsp65 in incomplete Freund's adjuvant, protection is substantial following immunization by injection with J774 macrophage-like tumour cells that express the protein from the mycobacterial gene via a retroviral vector . We here took the same vector, used it to transfect the gene into normal murine bone marrow cells in vitro, and then used the transfected cells to reconstitute haematopoiesis in lethally irradiated mice . Bone marrow-cell clonal expansion and production of the protein in vivo resulted in specific delayed-type hypersensitivity and protection against challenge with Mycobacterium tuberculosis (M . tuberculosis) in about half of recipients . Counts of live bacteria in liver at 3 weeks were fivefold lower in delayed-type hypersensitivity (DTH)-positive than in DTH-negative mice . Other mice acquired neither DTH nor protection despite the presence of the protein in peripheral blood. Plant Mol Biol, 1995 Dec, 29(5), 933 - 45 Light-dependent chlorophyll a biosynthesis upon chlL deletion in wild-type and photosystem I-less strains of the cyanobacterium Synechocystis sp . PCC 6803; Wu Q et al.; Part of the chlL gene encoding a component involved in light-independent protochlorophyllide reduction was deleted in wild type and in a photosystem I-less strain of Synechocystis sp . PCC 6803 . In resulting mutants, chlorophyll biosynthesis was fully light-dependent . When these mutants were propagated under light-activated heterotrophic growth conditions (in darkness except for 15 min of weak light a day) for several weeks, essentially no chlorophyll was detectable but protochlorophyllide accumulated . Upon return of the chlL- mutant cultures to continuous light, within the first 6 h chlorophyll was synthesized at the expense of protochlorophyllide at a rate independent of the presence of photosystem I . Chlorophyll biosynthesized during this time gave rise to a 685 nm fluorescence emission peak at 77 K in intact cells . This peak most likely originates from a component different from those known to be directly associated with photosystems II and I . Development of 695 and 725 nm peaks (indicative of intact photosystem II and photosystem I, respectively) required longer exposures to light . After 6 h of greening, the rate of chlorophyll synthesis slowed as protochlorophyllide was depleted . In the chlL- strain, greening occurred at the same rate at two different light intensities (5 and 50 microE m-2 s-1), indicating that also at low light intensity the amount of light is not rate-limiting for protochlorophyllide reduction . Thus, in this system the rate of chlorophyll biosynthesis is limited neither by biosynthesis of photosystems nor by the light-dependent protochlorophyllide reduction . We suggest the presence of a chlorophyll-binding 'chelator' protein (with 77 K fluorescence emission at 685 nm) that binds newly synthesized chlorophyll and that provides chlorophyll for newly synthesized photosynthetic reaction centers and antennae. J Laryngol Otol, 1995 Dec, 109(12), 1168 - 75 Pharyngeal trauma in children--accidental and otherwise; Tostevin PM et al.; Pharyngeal perforation is an uncommon injury in children . Most reported cases to date have been secondary to instrumentation or penetrating wounds . Laceration to the pharyngeal wall may introduce air, secretions and bacteria into the parapharyngeal space and mediastinum and consequently has potentially life-threatening sequelae . The management of these injuries is controversial . We present a series of four children who suffered pharyngeal trauma, accidentally and otherwise, and discuss their management . We recommend a high index of suspicion of pharyngeal injury in all cases of oropharyngeal trauma and overnight admission to hospital for observation until an accurate diagnosis has been established . Non-accidental injury of the child must be seriously considered in all cases. Eur J Biochem, 1995 Dec 1, 234(2), 592 - 7 Purification and properties of coenzyme F390 hydrolase from Methanobacterium thermoautotrophicum (strain Marburg); Vermeij P et al.; 8-Hydroxyadenylylated coenzyme F420 (coenzyme F390-A) is formed in methanogenic bacteria upon oxidative stress . After reinstatement of anaerobic conditions, coenzyme F390 is degraded into coenzyme F420 and AMP . The enzyme catalyzing the latter reaction, coenzyme F390 hydrolase, was purified to homogeneity from Methanobacterium thermoautotrophicum strain Marburg 355-fold to a specific activity of 12.1 mumol.min-1.mg protein-1 . The enzyme consisted of one polypeptide of approximately 27 kDa . Coenzyme F390 hydrolase displayed an apparent Km for coenzyme F390 of 40 microM . The enzyme required the presence of a reducing agent like dithiothreitol to become active . Activity could be manipulated by applying various ratios of reduced and oxidized dithiothreitol . Activation proceeded by a two-electron reduction, which indicates that one S-S bridge is involved the activation/inactivation of the enzyme . Dithiothreitol could be replaced by the methanogenic C1-carrier 2-mercaptoethanesulfonate (H-S-CoM), but not by N7-mercaptoheptanoyl-L-threonine phosphate (H-S-HTP) or other naturally occurring thiol-containing compounds . The addition of the heterodisulfide of H-S-CoM and H-S-HTP (CoM-S-S-HTP) diminished the stimulatory effect of H-S-CoM. Clin Exp Immunol, 1995 Dec, 102(3), 456 - 61 Peripheral cell-mediated immune response to mycobacterial antigens in inflammatory bowel disease; Rowbotham DS et al.; A mycobacterial etiology has been proposed in Crohn's disease (CD) . We have sought evidence of increased or modified T lymphocyte immune responses to Mycobacterium tuberculosis and Myco, paratuberculosis in patients with CD (n = 13), compared with ulcerative colitis (UC; n = 17) and controls (n = 17) . Peripheral blood cells were cultured with phytohaemagglutinin (positive mitogen control), mycobacterial purified protein derivative (PPD) preparations, lysates, column fractions and whole, heat-killed bacteria . Responses of T cells and T cell subsets were assessed by expression of activation markers (CD25, CD69), coupled with blastogenesis assays (3H-thymidine uptake) and estimates of proliferation . Virtually all patients responded to Myco . paratuberculosis and Myco . tuberculosis antigens . There were no significant differences between patient groups, although there was a very high overall correlation (r = 0.95; P < 0.0001) between responses to the two mycobacterial species . Most of the activation and proliferative responses resided in the CD4+ (T helper) subset . Although up to 15% of CD8+ (suppressor/cytotoxic) cells also became activated, the CD8+ cells did not proliferate subsequently . Cells expressing the alternate gamma delta form of the T cell receptor (TCR gamma delta+) did not activate or proliferate in response to mycobacterial antigens . There were no differences in any of these parameters between patient groups . We conclude that there is no specific increase or alteration in cell-mediated anti-mycobacterial immunity in inflammatory bowel disease (IBD) . Thus our data do not support a mycobacterial etiopathology of Crohn's disease. Curr Microbiol, 1995 Dec, 31(6), 377 - 81 Specific PCR detection and identification of Xylella fastidiosa strains causing citrus variegated chlorosis; Pooler MR et al.; By cloning and sequencing specific randomly amplified polymorphic DNA (RAPD) products, we have developed pairs of PCR primers that can be used to detect Xylella fastidiosa in general, and X . fastidiosa that cause citrus variegated chlorosis (CVC) specifically . We also identified a CVC-specific region of the X . fastidiosa genome that contains a 28-nucleotide insertion, and single base changes that distinguish CVC and grape X . fastidiosa strains . When using RAPD products to develop specific PCR primers, we found it most efficient to screen for size differences among RAPD products rather than presence/absence of a specific RAPD band. J Bacteriol, 1995 Dec, 177(24), 7210 - 21 Interactive regulation of Azorhizobium nifA transcription via overlapping promoters; Loroch AI et al.; The Azorhizobium nifA promoter (PnifA) is positively regulated by two physiological signal transduction pathways, NtrBC, which signals anabolic N status, and FixLJK, which signals prevailing O2 status . Yet, PnifA response (gene product per unit time) to these two activating signals together is more than twice that of the summed, individual signals . In the absence of NIFA, a negative PnifA autoregulator, the fully induced PnifA response is more than 10-fold greater than that of summed, individual signals . Given this synergism, these two signal transduction pathways must interactively regulate PnifA activity . PnifA carries three cis-acting elements, an anaerobox, which presumably binds FIXK, a NIFAbox, which presumably binds NIFA itself, and a sigma 54 box, which presumably binds sigma 54 initiator, a subunit of RNA polymerase . For combinatorial analysis, single, double, and triple promoter mutations were constructed in these cis-acting elements, and PnifA activities were measured in six different trans-acting background, i.e., fixK, fixJ, nifA, ntrC, rpoF, and wild type . Under all physiological conditions studied, high-level PnifA activity required both FIXK in trans and the anaerobox element in cis . Surprisingly, because PnifA was hyperactive with a mutated sigma 54box, this cis-acting element mediates both negative and positive control . Because PnifA hyperactivity also required a wild-type upstream NIFAbox element, even in the absence of NIFA, a second upstream nifA transcription start superimposed on the NIFAbox element was hypothesized . When nifA mRNA 5' start points were mapped by primer extension, both a minor upstream transcript(s) starting 45 bp distal to the anaerobox and a major downstream transcript starting 10 bp distal to the sigma 54 box were observed . In Azorhizobium, RNA polymerase sigma 54 initiator subunits are encoded by a multigene family, which includes rpoF and rpoN genes . Because rpoF mutants show an Ntr+ phenotype, whereas rpoN mutants are Ntr-, multiple sigma 54 initiators are functionally distinct . Two independent rpoF mutants both show a tight Nif- phenotype . Moreover, rpoF product sigma 54F is absolutely required for high-level PnifA activity . In summary, the Azorhizobium nifA gene carries overlapping housekeeping-type and sigma 54-type promoters which interactively respond to different signals . Effectively, the upstream, housekeeping-type promoter responds to FIXK and positively regulates the downstream, sigma 54-type promoter . The downstream, sigma 54-type promoter responds to NTRC and negatively regulates the upstream, housekeeping-type promoter . In terms of transcript yield, the upstream, housekeeping-type promoter is therefore weak, and the downstream, sigma 54-type promoter is strong. J Bacteriol, 1995 Dec, 177(24), 7041 - 9 In vitro recognition of the replication origin of pLS1 and of plasmids of the pLS1 family by the RepB initiator protein; Moscoso M et al.; Rolling-circle replication of plasmid pLS1 is initiated by the plasmid-encoded RepB protein, which has nicking-closing (site-specific DNA strand transferase) enzymatic activity . The leading-strand origin of pLS1 contains two regions, (i) the RepB-binding site, constituted by three directly repeated sequences (iterons or the bind region), and (ii) the sequence where RepB introduces the nick to initiate replication (the nic region) . A series of plasmids, belonging to the pLS1 family, show features similar to those of pLS1 and have DNA sequences homologous to the pLS1 nic region . In addition, they all share homologies at the level of their Rep proteins . However, the bind regions of these plasmids are, in general, not conserved . We tested the substrate specificity of purified RepB of pLS1 . The RepB protein has a temperature-dependent nicking-closing action on supercoiled pLS1, as well as on recombinant plasmid DNAs harboring the pLS1 nic region . The DNA strand transferase activity of pLS1-encoded RepB was also assayed on two plasmids of the pLS1 family, namely, pE194 and pFX2 . DNAs from both plasmids were relaxed by RepB, provided they had a proper degree of supercoiling; i.e., it was necessary to modulate the supercoiling of pE194 DNA to achieve RepB-mediated DNA relaxation . Single-stranded oligonucleotides containing the nic regions of various plasmids belonging to the pLS1 family, including those of pE194 and pFX2, were substrates for RepB . In vitro, the RepB protein does not need to bind to the iterons for its nicking-closing activity. J Infect Dis, 1995 Dec, 172(6), 1598 - 601 Interaction with human immunodeficiency virus type 1 modulates innate effector functions of human monocytes; Zerlauth G et al.; The effect of human immunodeficiency virus (HIV) type 1 on human mononuclear phagocyte effector functions in response to infection with bacteria of the Mycobacterium avium-intracellular complex (MAC) was investigated . The results showed that interaction of HIV-1 or its constituents with CD4 expressed in the monocyte membrane led to substantial impairment of monocyte capacity to restrict the intracellular growth of MAC . This was accompanied by substantially decreased production of tumor necrosis factor-alpha by HIV-1-exposed and MAC-infected monocytes . However, productive HIV-1 infection of monocytes was not required to induce the observed effects . These studies suggest that HIV-1 may interfere with innate mononuclear phagocyte function . This may be of physiologic importance in the late stages of AIDS, when an impaired T cell immunity can no longer provide proper immune-activating signals, and may help to explain the undue susceptibility to MAC infections in these patients. J Immunol, 1995 Dec 1, 155(11), 5343 - 51 Pulmonary surfactant protein A mediates enhanced phagocytosis of Mycobacterium tuberculosis by a direct interaction with human macrophages; Gaynor CD et al.; During initial infection with Mycobacterium tuberculosis, bacteria that reach the distal airspaces of the lung are phagocytosed by alveolar macrophages in the presence of pulmonary surfactant . Here we have examined the role of surfactant-associated protein A (SP-A) in phagocytosis of the virulent Erdman strain of M . tuberculosis by human monocyte-derived macrophages (MDMs) and human alveolar macrophages (HAMs) . Macrophage monolayers incubated with soluble SP-A from alveolar proteinosis patients (APP SP-A4) and recombinant rat SP-A (SP-Ahyp) demonstrated enhanced adherence of M . tuberculosis, 82 +/- 17% and 49 +/- 18%, respectively . Removal of SP-A from monolayers by washing before adding bacteria did not diminish the enhanced adherence . Fluorescence microscopy demonstrated that washed monolayers contained intracellular rather than surface-bound SP-A . These studies indicated a direct interaction between SP-A and the macrophage in mediating enhanced adherence of M . tuberculosis . Consistent with this interpretation, macrophage monolayers formed on human or rat SP-A (substrate SP-A) demonstrated enhanced adherence of M . tuberculosis to their apical surface (APP SP-A and native rat SP-A increased M . tuberculosis adherence by 102 +/- 16% and 102 +/- 25%, respectively) . Electron microscopy demonstrated increased numbers of phagocytosed bacteria in APP SP-A-treated MDM cross-sections . SP-A proteins devoid of carbohydrate failed to enhance M . tuberculosis adherence to macrophages . In contrast, heat-denatured APP SP-A enhanced adherence of bacteria equivalent to that of intact glycoprotein . Thus, the carbohydrate moieties of SP-A appear to be critical in the SP-A-macrophage interaction . Finally, mannan and anti-mannose receptor Ab completely inhibited the enhanced phagocytosis of M . tuberculosis observed with APP SP-A, providing evidence for up-regulation of macrophage mannose receptor activity . These studies implicate SP-A as an important modulator of alveolar macrophage function that results in an enhanced potential for M . tuberculosis to gain access to its intracellular niche. J Immunol, 1995 Dec 1, 155(11), 5273 - 9 Nuclear factor-IL6 activates the human IL-4 promoter in T cells; Davydov IV et al.; Positive regulatory element I (PRE-I) is a strong enhancer element essential for expression of the human IL-4 gene . To identify transcription factors binding to PRE-I, we screened a cDNA expression library from Jurkat T cells and isolated a cDNA encoding nuclear factor (NF)-IL6 (also known as C/EBP beta) . NF-IL6 mRNA was found in human Jurkat T cells and in the mouse Th2 clone D10, but not in Th1 clone 29 . rNF-IL6 expressed in bacteria was shown to specifically bind to PRE-I . PRE-I forms multiple DNA-protein complexes with nuclear extracts from Jurkat cells . Some of these complexes were demonstrated to contain NF-IL6 by using anti-C/EBP beta Abs . Overexpression of NF-IL6 enhanced expression of the chloramphenicol acetyl transferase reporter gene linked to the PRE-I-thymidine kinase or the human IL-4 promoter more than 10-fold in Jurkat cells . Promoter deletion studies revealed two additional NF-IL6 binding sites located at positions -44 to -36 (C/EBP proximal) and -87 to -79 (C/EBP medial), respectively . Our results demonstrate that NF-IL6 is involved in transcriptional activation of the human IL-4 promoter in T cells. J Bacteriol, 1995 Dec, 177(23), 6825 - 31 Identification and nucleotide sequences of mxaA, mxaC, mxaK, mxaL, and mxaD genes from Methylobacterium extorquens AM1; Morris CJ et al.; The DNA sequence for a 4.4-kb HindIII-XhoI Methylobacterium extorquens AM1 DNA fragment that is known to contain three genes (mxaAKL) involved in incorporation of calcium into methanol dehydrogenase (I . W . Richardson and C . Anthony, Biochem . J . 287:709-7115, 1992) was determined . Five complete open reading frames and two partial open reading frames were found, suggesting that this region contains previously unidentified genes . A combination of sequence analysis, mutant complementation data, and gene expression studies showed that these genes correspond to mxaSACKLDorf1 . Of the three previously unidentified genes (mxaC, mxaD, and orf1), mutant complementation studies showed that mxaC is required for methanol oxidation, while the function of the other two genes is still unknown. Infect Immun, 1995 Dec, 63(12), 4826 - 9 Isolation, cultivation, and partial characterization of the ELB agent associated with cat fleas; Radulovic S et al.; ELB rickettsiae from cat flea homogenates were recovered in tissue culture cells following sequential passage through laboratory rats and the yolk sacs of embryonated chicken eggs . Seven days after inoculation of ELB from the infected yolk sacs, Vero cells and L929 cells were observed to contain intracellular bacteria as demonstrated by Diff Quik and indirect immunofluorescence assay staining . The rickettsial and ELB identity of the cultured agent was confirmed by PCR detection of the 16S rRNA and citrate synthase genes and PCR-restriction fragment length polymorphism analysis of the 17-kDa conserved rickettsial antigen gene . The ELB rickettsiae induced plaques in Vero cells on day 11 postinfection . Rat anti-ELB serum reacted at 1:4,096 to cultured ELB and had lower reactivity to Rickettsia typhi Wilmington (1:1,024), Rickettsia akari Kaplan (1:512), and Rickettsia australis JC (1:64) . Spotted fever group polyclonal sera also exhibited lower reactivity to ELB than to the homologous antigen . Coomassie blue-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of the ELB isolate and two R . typhi strains were identical. J Trauma, 1995 Dec, 39(6), 1123 - 8 Influence of reaming versus nonreaming in intramedullary nailing on local infection rate: experimental investigation in rabbits; Melcher GA et al.; The question of whether the impairment of the endosteal blood supply, which is induced by nailing with reaming of the medullary cavity, increases the risk of a postoperative infection cannot be conclusively answered by studying existing literature . The aim of this study was to investigate the effect of medullary reaming on the occurrence of local infection based on an infection model in the rabbit tibia (n = 44) . An infection rate of 50% was found after unreamed nailing, as opposed to an infection rate of 64% after medullary reaming . The number of bacteria observed after reaming was significantly higher than after nail insertion without previous reaming . The differing susceptibilities to infection as observed in this model are statistically significant (p < or = 0.05). J Biol Chem, 1995 Dec 1, 270(48), 28938 - 45 Identification of two novel Dictyostelium discoideum cysteine proteinases that carry N-acetylglucosamine-1-P-modification; Souza GM et al.; Dictyostelium discoideum makes multiple developmentally regulated lysosomal cysteine proteinases . One of these, a lysosomal enzyme called proteinase I, contains a cluster of GlcNAc-alpha-1-P-Ser residues . We call this phosphoglycosylation . To study its function, a cDNA library from vegetative cells was screened, and two novel cysteine proteinase clones were characterized (cprD and cprE) . Each of them has highly conserved regions expected for cysteine proteinases, but unlike any other, each has a serine-rich domain containing three distinct motifs, poly-S, SGSQ, and SGSG . cprD and cprE cDNAs were overexpressed in Dictyostelium and the active enzymes identified . cprD codes for a protein of approximately 36 kDa (CP4), which is recognized by monoclonal antibodies against GlcNAc-1-P and fucose . cprE corresponds to a 29-kDa protein, which is recognized by antibodies against GlcNAc-1-P . mRNA for both enzymes is present in the vegetative phase and increases during growth on bacteria but decreases throughout development . When the formation of the fruiting body is complete the mRNA for both messages is detected again but in very low levels . Having cloned cDNAs for proteins that carry GlcNAc-1-P should allow us to probe the function of the carbohydrate in these putative lysosomal enzymes. J Biol Chem, 1995 Dec 1, 270(48), 28897 - 902 Isolation of MEK5 and differential expression of alternatively spliced forms; English JM et al.; The prototype mitogen-activated protein (MAP) kinase module is a three-kinase cascade consisting of the MAP kinase, extracellular signal-regulated protein kinase (ERK) 1 or ERK2, the MAP/ERK kinase (MEK) MEK1 or MEK2, and the MEK kinase, Raf-1 or B-Raf . This and other MAP kinase modules are thought to be critical signal transducers in major cellular events including proliferation, differentiation, and stress responses . To identify novel mammalian MAP kinase modules, polymerase chain reaction was used to isolate a new MEK family member, MEK5, from the rat . MEK5 is more closely related to MEK1 and MEK2 than to the other known mammalian MEKs, MKK3 and MKK4 . MEK5 is thought to lie in an uncharacterized MAP kinase pathway, because MEK5 does not phosphorylate the ERK/MAP kinase family members ERK1, ERK2, ERK3, JNK/SAPK, or p38/HOG1, nor will Raf-1, c-Mos, or MEKK1 highly phosphorylate it . Alternative splicing results in a 50-kDa alpha and a 40-kDa beta isoform of MEK5 . MEK5 beta is ubiquitously distributed and primarily cytosolic . MEK5 alpha is expressed most highly in liver and brain and is particulate . The 23 amino acids encoded by the 5' exon in the larger alpha isoform are similar to a sequence found in certain proteins believed to associate with the actin cytoskeleton; this alternatively spliced modular domain may lead to the differential subcellular localization of MEK5 alpha. Chest, 1995 Dec, 108(6), 1632 - 9 Reappraisal of distal diagnostic testing in the diagnosis of ICU-acquired pneumonia; Timsit JF et al.; BACKGROUND: The thresholds of the diagnostic procedures performed to diagnose ICU-acquired pneumonia (IAP) are either speculated or incompletely tested . PURPOSE: To evaluate the best threshold of protected specimen brush (PSB), plugged telescoping catheter (PTC), BAL culture (BAL C), and direct examination of cytocentrifugated lavage fluid (BAL D) to diagnose IAP . Each mechanically ventilated patient with suspected IAP underwent bronchoscopy successively with PSB, PTC, and BAL in the lung segment identified radiographically . POPULATION: One hundred twenty-two episodes of suspected IAP (occurring in 26% of all mechanically ventilated patients) were studied . Forty-five patients had definite IAP, and 58 had no IAP . Diagnosis was uncertain in 19 cases . RESULTS: Using the classic thresholds, sensitivity was 67% for PSB, 54% for PTC, 59% for BAL D, and 77% for BAL C . Specificity was 88% for PSB, 77% for PTC, 98% for BAL D, and 77% for BAL C . We used receiver operating characteristics methods to reappraise thresholds . Decreasing the thresholds to 500 cfu/mL for PSB, 10(2) cfu/mL for PTC, 2% cells containing bacteria for BAL D, 4 x 10(3) cfu/mL for BAL C increased the sensitivities (plus 14%, 23%, 25%, 10%, respectively) and moderately decreased the specificities (minus 4%, 9%, 2%, 4%, respectively) of the four examinations . The association of PSB with a 500 cfu/mL threshold and BAL D with a 2% threshold recovered all but one episode of pneumonia (SE 96 +/- 4%) with a 84 +/- 10% specificity . For a similar ICU population, these "best" thresholds increased negative predictive value with a minimal decrease of positive predictive value . They need to be confirmed in multiple ICU settings in prospective fashion. Orig Life Evol Biosph, 1995 Dec, 25(6), 549 - 64 The phylogeny of tRNAs seems to confirm the predictions of the coevolution theory of the origin of the genetic code; Di Giulio M; An extensive analysis of the evolutionary relationships existing between transfer RNAs, performed using parsimony algorithms, is presented . After building up an estimate of the tRNA ancestral sequences, these sequences are then compared using certain methods . The results seem to suggest that the coevolution hypothesis (Wong, J.T., 1975, Proc . Natl . Acad . Sci . USA 72, 1909-1912) that sees the genetic code as a map of the biosynthetic relationships between amino acids is further supported by these results, as compared to the hypotheses that see the physicochemical properties of amino acids as the main adaptative theme that led to the structuring of the genetic code. Am J Surg, 1995 Dec, 170(6), 665 - 9; discussion 669-70 Comparison of diagnostic specimens and methods to evaluate infected venous access ports; Whitman ED et al.; BACKGROUND: Implanted venous access port infection can be difficult to diagnose and treat . If device removal is necessary, confirming port infection is problematic . MATERIALS AND METHODS: Culture specimens from three sites, catheter tip (Tip), port pocket, and the material within the reservoir (Inside), were sent from ports removed for potential infection . The results of these cultures were compared to preremoval peripheral and central blood cultures . RESULTS: Forty-five ports were removed for suspected infection . Confirmed port infection was defined as positive culture(s) from one or more experimental specimen(s) . In 29 evaluable cases, the Inside specimens were completely predictive . Tip specimens were less accurate, even with a lower diagnostic threshold . In 7 of 19 confirmed infections, only the Inside culture was diagnostic . CONCLUSION: The most predictive culture specimen in a potentially infected port is the thrombotic material inside the reservoir. Pediatrics, 1995 Dec, 96(6), 1137 - 42 Serologic responses to Bartonella and Afipia antigens in patients with cat scratch disease; Szelc-Kelly CM et al.; OBJECTIVE . To assess the serologic response to Afipia and Bartonella, previously named Rochalimaea, in patients with cat scratch disease (CSD) and a healthy control group . DESIGN . Prospective, controlled trial . SETTING: Referral clinic and hospitalized patients in a university medical center . PARTICIPANTS . Eighty patients with CSD and 57 healthy control subjects of similar age . MAIN OUTCOME MEASURES . The immune responses to Afipia felis and Bartonella henselae were evaluated by a newly developed enzyme-linked immunosorbent assay (ELISA) in patients with CSD and healthy control subjects . Responses to B henselae were also measured by indirect fluorescent antibody (IFA) tests . Antibody levels to Bartonella quintana were measured by ELISA and IFA in a limited number of patients and control subjects . RESULTS . Of the 80 patients with clinical CSD, 56 had positive results of CSD skin tests . ELISA antibody levels to A felis did not differ between patients and control subjects, but immunoglobulin M (IgM) and IgG ELISA antibodies to B henselae and B quintana were significantly higher in patients than in control subjects . IFA responses to B henselae and B quintana were also significantly higher in patients than in control subjects . CONCLUSION . Patients with CSD had significant serologic responses to B henselae and B quintana but not to A felis, suggesting that the causative agent of CSD is antigenically related to the Bartonella genus and not to Afipia . The Bartonella IgM ELISA and IFA assay were both sensitive and specific and may be used to establish the diagnosis of CSD. Carbohydr Res, 1995 Nov 30, 278(1), 143 - 53 Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain 49; Ferreira F et al.; The structure of Butyrivibrio fibrisolvens strain 49 capsular polysaccharide has been investigated mainly by sugar and methylation analysis, partial chemical degradations, NMR spectroscopy, and mass spectrometry . The results suggest that the polysaccharide is composed of pentasaccharide repeating units having the following structure . {formula: see text} The polysaccharide contains O-acetyl groups, one of which is substituted to O-3 of the 4-substituted alpha-D-Galp residue, while others occur in non-stoichiometric amounts at other locations. Biochem Pharmacol, 1995 Nov 27, 50(11), 1753 - 9 Auranofin inhibits the induction of interleukin 1 beta and tumor necrosis factor alpha mRNA in macrophages; Bondeson J et al.; Gold compounds are widely used in the treatment of rheumatoid arthritis, but their mechanisms of action remain unclear . We demonstrate here that auranofin (AF) (0.1-3 microM), but neither the hydrophilic gold compounds aurothiomalate (ATM) and aurothioglucose nor methotrexate or D-penicillamine, inhibits the induction of interleukin 1 beta and tumor necrosis factor (TNF) alpha mRNA and protein by either zymosan, lipopolysaccharide (LPS), or various bacteria in mouse macrophages . The auranofin-mediated inhibition of the induction of TNF-alpha mRNA was stronger than that of interleukin (IL) 1 beta mRNA . AF, but not the other drugs, also inhibited zymosan-induced mobilization of arachidonate . The fact that AF inhibited the induction of mRNA for both these proinflammatory cytokines, irrespective of which stimulus was used, may indicate that it affects some common signal transduction step vital to their induction. Ann N Y Acad Sci, 1995 Nov 27, 772, 212 - 26 A genetic approach to idiotypic vaccination for B cell lymphoma; Stevenson FK et al.; Idiotypic immunoglobulin expressed by a B cell tumor presents a clear tumor antigen which could be attacked by vaccination of the host . Vaccination with idiotypic protein has been shown to induce protective immunity against lymphoma, but application to patients is limited by the requirement of "personal" vaccines for each patient . A genetic approach enables V-region sequences encoding idiotypic antigen to be rescued from tumor biopsies, and to be assembled as scFv fragments . These can be expressed in bacteria to produce recombinant protein, or used directly as naked DNA vaccines . Intramuscular injection of idiotypic DNA from a mouse B cell lymphoma induces low levels of syngeneic anti-idiotypic antibody in serum . Response can be stimulated by co-injection of DNA plasmids encoding either IL-2 or GM-CSF, and T cells which proliferate in response to idiotypic IgM are generated . However, protection against tumor appears to be blocked by continuing secretion of idiotypic antigen from the persisting vaccine vector, which forms immune complexes with serum antibody . Methods for regulating the level of scFv to engage the immune system, but not to block the effector arm are being investigated . Similar control will be applicable to the cytokine vectors, which can deliver encoded cytokines designed to activate immune pathways for tumor destruction . Experience gained in lymphoma may be extended to other tumors with defined tumor antigens. J Chromatogr A, 1995 Nov 24, 717(1-2), 71 - 4 Differences between natural and recombinant interleukin-2 revealed by gel electrophoresis and capillary electrophoresis; Knuver-Hopf J et al.; High-performance capillary electrophoresis (HPCE) is shown to be useful for analysis of interleukin-2 (IL-2) in its native state under non-reducing conditions . The results obtained were compared with those from analysis of IL-2 by protein blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) under denaturing and reducing conditions . In addition, resolution of the different glycosylated and non-glycosylated natural IL-2 species was achieved by HPCE . The HPCE electropherogram of native IL-2 could easily generate quantitative amounts of the different naturally occurring IL-2 species . For HPCE of IL-2 run times of less than 10 min are sufficient, and only extremely small amounts of IL-2 are needed . In this report, human IL-2 expressed in bacteria has been analysed by HPCE and the existence of two recombinant IL-2 forms was demonstrated. Biochem Biophys Res Commun, 1995 Nov 22, 216(3), 785 - 92 Fibronectin binding domain of P . gingivalis fimbriae; Sojar HT et al.; P . gingivalis fimbriae play an important role in attachment of bacteria to various salivary components as well as to host cells and matrix proteins including fibronectin . In the present study, we investigated the binding domain of P . gingivalis fimbriae to fibronectin using synthetic peptides . A series of 20 mer fimbrillin peptides were used . Binding of fibronectin to purified fimbriae and synthetic peptides was assayed using polyclonal fibronectin antibodies as well as iodinated fibronectin . Purified fimbriae and peptide 126-146 (RMAFTEIKVQMSAAYDNIYTF) showed high levels of binding to fibronectin, while peptide 318-337(HLNVQCTVAEWVLVGQNATW) showed low but statistically significant binding . Our results suggest V-Q-X-X-X-A or V-X-X-X A common domain/domains present in both peptides might be involved in protein-protein interaction between P . gingivalis fimbriae and fibronectin. Gene, 1995 Nov 20, 165(2), 243 - 8 A multifunctional Urechis caupo protein, PAPS synthetase, has both ATP sulfurylase and APS kinase activities; Rosenthal E et al.; The synthesis of 3'-phosphoadenosine-5'-phosphosulfate (PAPS) from inorganic sulfate and ATP requires two enzymes, ATP sulfurylase (SUL) and adenosine-5'-phosphosulfate kinase (KIN) . In bacteria, fungi, yeast and plants, the two enzymes are present on separate polypeptide chains . We have identified the first animal gene coding for these enzymes . In the marine worm, Urechis caupo (Uc), both SUL and KIN are present on a single polypeptide chain . This protein, which we call PAPS synthetase (PAPSS), is able to complement yeast mutants lacking either enzyme . The Uc PAPSS mRNA is present in oocytes, but is not translated until after fertilization . At least three adult tissues, gut, ceolomocytes and body wall, also contain the mRNA, but at lower concentrations than are found in embryos . Partial sequences of a similar gene from Caenorhabditis elegans (Ce) were detected in a search of the GenBank expressed sequence tag database . Comparison of these Uc and Ce PAPSS sequences with the sequences of cloned genes from non-animal organisms strongly suggests that the animal genes evolved through the fusion of the SUL- and KIN-encoding genes from lower organisms. Gene, 1995 Nov 20, 165(2), 239 - 42 A cDNA encoding ribosomal protein L3 from the parasitic nematode Toxocara canis; Moore J et al.; A cDNA encoding the ribosomal (r) protein L3 of the parasitic nematode Toxocara canis was isolated from a library constructed from mRNA of the infective larval stage . The encoded protein has a high degree of similarity to r-protein L3 from other organisms, including mammals, yeast, plants and bacteria . The mRNA encoding r-protein L3 is derived from a single-copy gene, and experimental evidence would suggest that it contains the pan-nematode splice leader sequence at its 5' end and that the gene is interrupted by at least three introns. FEBS Lett, 1995 Nov 20, 375(3), 280 - 2 Enzymatic and immunological activity of 4000 years aged bone alkaline phosphatase; Weser U et al.; Structurally intact and functionally active human bone alkaline phosphatase was isolated from clavicle fragments of IDU, an Egyptian mummy of the Old Kingdom (2150 +/- 50 BC) . Both anion exchange and affinity chromatographies were employed to optimise the preparation of the ancient enzyme resulting in a specific activity of 180 +/- 30 mU/mg . The intactness of the bone enzyme fractions of the wheat-germ lectin affinity chromatography was successfully demonstrated in an ELISA using the monoclonal antibody BAP A . Fortunately, the mummified bone was not contaminated by fungi or bacteria. Biochemistry, 1995 Nov 14, 34(45), 14722 - 32 Fourier transforms infrared difference spectroscopy of secondary quinone acceptor photoreduction in proton transfer mutants of Rhodobacter sphaeroides; Nabedryk E et al.; In order to investigate the changes of protonation or environment of carboxylic residues occurring upon photoreduction of the secondary quinone acceptor (QB) in the reaction center (RC) of the photosynthetic bacteria Rhodobacter sphaeroides 2.4.1., we have performed light-induced Fourier transform infrared (FTIR) spectroscopy on RCs from wild-type (Wt) and several site-directed mutants . The FTIR QB-/QB spectra have been obtained at pH 7 upon single-saturating flash excitation for native RCs and RC mutants containing either a single-site mutation, with Gln at L212 (EQ L212), Asn at L213 (DN L213), or Asn at L210 (DN L210), or a double-site mutation with both Gln at L212 and Asn at L213 (EQ L212 + DN L213) . The assignment of an IR band to the protonation/deprotonation of a particular carboxylic side chain was analyzed by combining the effects of site-directed mutagenesis and 1H/2H isotope exchange . A positive band at 1728 cm-1 in the QB-/QB spectra was observed in Wt, DN L213, and DN L210 and was absent in the mutants EQ L212 and EQ L212 + DN L213 . The intensity of the 1728 cm-1 band was significantly reduced in 2H2O, and a new feature appears at 1717 +/- 1 cm-1 . Furthermore, the amplitude of the 1728 cm-1 band was similar in native and DN L210 RCs but was increased in DN L213 . This band is attributed to partial proton uptake by Glu L212 estimated to be 0.3-0.4 H+/QB- in native and DN L210 RCs and O.5-0.6 H+/QB- in DN L213 RCs . In contrast, the FTIR QB-/QB spectra show no evidence for change of protonation or environment of Asp L213 upon QB- formation . The increased protonation of Glu L212 in DN L213 RCs is explained by a decreased Glu L212 pKa value due to the loss of a negatively charged Asp L213 . Part of a small differential signal at 1732 (+)/1740 (-) cm-1 that is affected by 1H/2H exchange is tentatively assigned to an environmental shift of the protonated Asp L210 . A negative signal at 1685 cm-1 is propose to arise from the absorption change of the amide I carbonyl mode of Glu L212.(ABSTRACT TRUNCATED AT 400 WORDS) Biochemistry, 1995 Nov 14, 34(45), 14675 - 86 Influence of charge and polarity on the redox potentials of high-potential iron-sulfur proteins: evidence for the existence of two groups; Heering HA et al.; We have investigated the HiPIPs from Ectothiorhodospira vacuolata (iso-1 and iso-2), Chromatium vinosum, Rhodocyclus gelatinosus, Rhodocyclus tenuis (strain 2761), Rhodopila globiformis, and Rhodospirillum salinarum (iso-2) by direct electrochemistry . Using a glassy carbon electrode with a negatively charged surface, direct, unpromoted electrochemistry is possible with the positively charged HiPIPs . With the negatively charged HiPIPs, the positively charged and flexible bridging promoter poly(L-lysine) is required . The stability of the response can be improved by morpholin, aspartate, tryptophan, or 4,4'-dipyridyl . These "stabilizers" prevent the blocking of the electrode by denatured protein . The redox potential of 500 mV found for R . salinarum iso-2 is the highest HiPIP potential reported . The presence of histidines in the sequence does not per se predict a pH-dependent redox potential . Only C . vinosum and R . gelatinosus HiPIPs show a weak but significant pH dependence with a difference of 35 mV between the low- and the high-pH form and maximum slopes of -20 mV/unit . The dependence of the midpoint potential on temperature and on ionic strength varies over the different HiPIPs . The dependence of the potentials on square root of I cannot be fully explained by the Debye-Huckel theory because the linearity exceeds the limiting concentration and only small negative slopes are observed (o to -28 mV/square root of M) Combination of the sequences, the optical spectra, the overall charges, and the redox thermodynamics suggests that existence of two groups of HiPIPs . One group consists of Chromatium-like HiPIPs with redox potentials between 300 and 350 mV, modulated only by the solvation of the cluster . The second group is formed by Ectothiorhodospira-like HiPIPS with potentials between 50 and 500 mV, modulated by the overall charge of the peptide (25 mV/unit) and by the solvation of the cluster. Virology, 1995 Nov 10, 213(2), 676 - 9 Inhibition of viral aphid transmission by the N-terminus of the maize dwarf mosaic virus coat protein; Salomon R et al.; Since removal of the exposed N-terminus of the coat protein of some potyviruses abolishes aphid transmission, the role of this coat protein region of maize dwarf mosaic potyvirus (MDMV) in aphid transmission was investigated . The viral cDNA encoding this region was cloned and expressed as a fusion protein in bacteria . The resulting purified N-terminus of the coat protein was used in controlled aphid transmission experiments in competition with MDMV . The results show that this region inhibits aphid transmission of MDMV, indicating a direct involvement of the N-terminal region of the coat protein in aphid transmission. Gene, 1995 Nov 7, 165(1), 87 - 91 Conservation and variability in Archaea: protein antigens with tandem repeats encoded by a cluster of genes with common motifs in Methanosarcina mazei S-6; Mayerhofer LE et al.; Three open reading frames, orf492, orf375 and orf783, were identified in a 5.9-kb DNA fragment from the genome of Methanosarcina mazei S-6 that code for proteins recognized by antibodies against cell-surface antigens . The deduced amino-acid (aa) sequences of orfs492 and 375, i.e., ORF492 and ORF375, contain seven and four copies of an approx . 42-aa repeat, respectively . The aa sequence of ORF783 contains nine copies of an approx . 85-aa repeat, one of which is also present once in each of the first two ORFs . The organization of the repeats is similar to that of some Gram+ cell-wall-associated proteins . Comparative analyses of aa sequences, compositions and hydropathy profiles of the archaeal ORFs showed similarity with surface (S-) layer and outer-membrane proteins of Bacteria and Archaea. Gene, 1995 Nov 7, 165(1), 143 - 4 An IS903-based vector for transposon mutagenesis and the isolation of gene fusions; Derbyshire KM; A derivative of the IS903 transposon (Tn) is described that is capable of creating lacZ gene fusions upon transposition . It should find wide use as a tool for Tn mutagenesis in bacteria since it can be used both to generate mutants and to examine gene expression . The transposase-encoding gene (tnp) is located outside the Tn in the vector, thus Tn insertions into a genome are stably maintained in the absence of its cis-acting transposase (Tnp) . The element carries a KmR gene allowing for the direct selection of transposition events in hosts that cannot support pBR322 plasmid replication and facilitating the subcloning of genes into which the Tn has inserted. Endoscopy, 1995 Nov, 27(9), 671 - 5 Endotoxemia and mediator release during colonoscopy; Berger D et al.; BACKGROUND AND STUDY AIMS: Previous clinical and experimental studies have shown evidence of a leakage of whole bacteria and bacterial products after major trauma through the gut barrier . By determining plasma endotoxin levels, products of the arachidonic pathway, interleukin-6, and the endotoxin-neutralizing capacity (ENC) of plasma during colonoscopy, we studied the gut barrier function and the pathogenetic sequelae of mediator release during a minimally invasive procedure . PATIENTS AND METHODS: Thirty-two patients were enrolled in a controlled prospective study . Endotoxin and ENC were determined by a chromogenic modification of the limulus amebocyte lysate test . Prostanoids and interleukin-6 were measured using commercially available ELISA tests . C-reactive protein levels were checked by nephelometry . RESULTS: Twenty-one of the 32 patients had elevated endotoxin plasma levels during colonoscopy . In one patient, gut-derived bacteria were detected in plasma . ENC decreased after 5 min, and thromboxane B2 levels also started to increase at that time . No acute-phase response took place after 24 h . CONCLUSION: During colonoscopy, endotoxin can be detected in blood . ENC measurement was shown to be even more sensitive . The pathogenetic sequelae leading to gut barrier failure remain unclear, because mediator release and endotoxemia, as checked by ENC, took place simultaneously. Pathol Res Pract, 1995 Nov, 191(11), 1072 - 77 Suppurative lesions without prominent epithelioid cell response in abscess-forming granulomatous lymphadenitis; Kojima M et al.; To clarify the clinicopathological significance of the suppurative lesions without an epithelioid granulomatous response (SLs without Ep) in lymph nodes and their relationship to abscess-forming granulomatous lymphadenitis (AGL) and cat scratch disease (CSD), 10 cases were assessed clinicopathologically and immunohistologically . SLs without Ep were located in the subcapsular sinus, paracortical area and medullary cords, but not in the germinal centers . The microabscesses were surrounded by collections of monocytoid B-lymphocytes (MBLs), histiocytes without epithelioid features, neutrophils, small lymphocytes and small numbers of plasma cells . The majority of the MBLs seen in the SLs without Ep were of the large cell type . The histological triad of toxoplasmic lymphadenitis, i.e., reactive follicular hyperplasia, small clusters of epithelioid cells and aggregates of MBLs, were also seen in all cases . Some of the clinical and pathological findings in our 10 cases were characteristic of CSD, i.e., (1) cat exposure before the lymphadenopathy was in four of the 10 cases, (2) occurrence in autumn and winter months in all cases, (3) typical suppurative granulomas surrounded by palisaded epithelioid cells were in four of the 10 cases, and (4) Warthin-Starry silver stain-positive bacteria were detected in seven of the 10 cases . The results of our study suggest that SLs without Ep are an early stage of CSD. Mol Microbiol, 1995 Nov, 18(4), 703 - 14 Mechanism of antigenic variation in Mycoplasma pulmonis: interwoven, site-specific DNA inversions; Bhugra B et al.; The chromosome of the murine pathogen Mycoplasma pulmonis undergoes rearrangements at a high frequency . We show that some of these rearrangements regulate the phase-variable expression of a cluster of genes (the vsa locus) that encode the variable V-1 surface antigens . Only one vsa gene is associated with an expression site; the other vsa genes are transcriptionally silent . The silent genes lack the 5' end region (promoter and ribosome-binding site) that is present in the expressed gene, and DNA rearrangements regulate gene expression by reassorting the 5' end region from an expressed gene with the 3' end region from a previously silent gene . All vsa rearrangements identified so far are site-specific DNA inversions that occur between copies of a specific 34 bp sequence that is conserved in each vsa gene . Interestingly, DNA inversions within the vsa locus apparently occur in concert with inversion of the hsd1 element, which regulates restriction and modification activity