Nature, 1991 Jul 25, 352(6333), 342 - 4 Recognition and plasma clearance of endotoxin by scavenger receptors; Hampton RY et al.; Lipid A is the active moiety of lipopolysaccharide (LPS, also referred to as endotoxin), a surface component of Gram-negative bacteria that stimulates macrophage activation and causes endotoxic shock . Macrophages can bind, internalize and partially degrade LPS, lipid A and its bioactive precursor, lipid IVA . We report here that lipid IVA binding and subsequent metabolism to a less active form by macrophage-like RAW 264.7 cells is mediated by the macrophage scavenger receptor . Scavenger-receptor ligands inhibit lipid IVA binding to, and metabolism by, RAW cells, and lipid IVA binds to type I and type II bovine scavenger receptors on transfected Chinese hamster ovary cells . Although in vitro competition studies with RAW cells indicate that scavenger receptor binding is not involved in LPS or lipid IVA-induced stimulation of macrophages, in vivo studies show that scavenger-receptor ligands greatly inhibit hepatic uptake of lipid IVA in mice . Thus, scavenger receptors expressed on macrophages may have an important role in the clearance and detoxification of endotoxin in animals. Ugeskr Laeger, 1991 Jul 22, 153(30), 2125 - 8 {Itching in the external ear--a side effect of ear plugs}; Madsen EF et al.; The object of this investigation was to assess the frequency of itching in the external auditory meatus in individuals who use hearing aid ear plugs (OP) and, simultaneously, to assess the cause of the itching . Seventy-six of the patients examined consecutively in the audiological department (ages 34-89 years) were questioned about itching and were submitted to an objective ear, nose and throat examination, audiometry and culturing from the external meatus for bacterial and fungal growth . In 20 patients, patch tests were made for allergic reactions from which the ear plugs were made (heat polymerized methyl methacrylate) . None of the 20 patients had become sensitized . Itching in the external auditory meatus was found to be a side effect of employment of ear plugs with an incidence of 39% as opposed to only seven in ears without ear plugs (p less than 0.05) . The incidence of itching was not reduced in ears with a ventilation channel in the ear plug . In 38% of the itching ears no objective changes were observed and, in the remaining cases, the changes were frequently limited . Potentially pathological bacterial growth was found to be significantly more in ears with ear plugs (1- greater than 16%, p less than 0.05) and in itching ears (4- greater than 24%, p less than 0.05) . In ears with potentially pathogenic bacteria, objective changes were nearly always found . In the vast majority of cases, the potentially pathogenic bacteria were Gram-negative, corresponding to the findings in external otitis in the tropics and mixed infections with fungi were frequently present.(ABSTRACT TRUNCATED AT 250 WORDS) Blood, 1991 Jul 15, 78(2), 387 - 93 Plasma antigen levels of the lipoprotein-associated coagulation inhibitor in patient samples; Novotny WF et al.; Human plasma contains an inhibitor of tissue factor-initiated coagulation known as the lipoprotein-associated coagulation inhibitor (LACI) or also known as the extrinsic pathway inhibitor (EPI) . A competitive fluorescent immunoassay was developed to measure the plasma concentration of LACI in samples from normal individuals and patients with a variety of diseases . The LACI concentration in an adult control population varied from 60% to 160% of the mean with a mean value corresponding to 89 ng/mL or 2.25 nmol/L . Plasma LACI levels were not decreased in patients with severe chronic hepatic failure, warfarin therapy, primary pulmonary hypertension, thrombosis, or the lupus anticoagulant . Plasma LACI antigen was decreased in some, but not all patients with gram-negative bacteremia and evidence for disseminated intravascular coagulation . Plasma LACI levels were elevated in women undergoing the early stages of labor (29%), in patients receiving intravenous tissue-type plasminogen activator (45%), and in patients receiving intravenous heparin (375%) . A radioligand blot of the pre- and post-heparin plasma samples shows the increase to be in a 40-Kd form of LACI . Very low levels of plasma LACI antigen were found in patients with homozygous abetalipoproteinemia and hypobetalipoproteinemia, diseases associated with low plasma levels of apolipoprotein B containing lipoproteins . Following the injection of heparin into one patient with homozygous abetalipoproteinemia, the plasma LACI antigen level increased to a level comparable with that in normal individuals after heparin treatment. Am J Ophthalmol, 1991 Jul 15, 112(1), 46 - 9 Ocular infections associated with Comamonas acidovorans; Stonecipher KG et al.; Comamonas acidovorans (Pseudomonas acidovorans) is a ubiquitous gram-negative rod . Although generally considered nonpathogenic, we found C . acidovorans to be associated with six cases of ocular infections . The organism was the only isolate in three cases, whereas an association of other organisms was present in three cases . The multiple resistance patterns of these strains to antibiotic susceptibility testing emphasizes the need for culturing ocular infections . We recommend the identification and susceptibility testing of all ocular gram-negative rod isolates. Circ Shock, 1991 Jul, 34(3), 298 - 310 Characterization of an endotoxemic baboon model of metabolic and organ dysfunction; Lindsey DC et al.; An anesthetized endotoxemic baboon model has been developed by infusing 2.0 mg E . coli endotoxin/kg i.v . over 1 hr (n = 7) . Animals were monitored for 5-7 days with analyses of: cardiovascular, metabolic, and organ dysfunction; acid base, hemostatic, and hematological alterations; as well as tumor necrosis factor (TNF) and interleukin-6 (IL-6) levels . Pathophysiologies detected at 2 hr included transient decreases in vascular resistance and blood pressure, a 157% increase in blood lactate, and a 90% decrease in circulating neutrophils . Organ dysfunction was not observed until 24 hr and, although thrombocytopenia was prevalent (-72% at 48 hr), disseminated intravascular coagulation (DIC) was not a major pathology . Hematocrit fell 21% by 24 hr and was -41% at 5-7 days . Serum TNF peaked at 90 min (7.8 +/- 0.2 ng/mL) and was undetectable after 3 hr . IL-6 also increased early, peaked at 3 hr (3872 +/- 846 U/mL) and was still detectable at 24 hr . A low mortality primate model of gram-negative sepsis has been developed that is characterized by early cardiovascular and metabolic dysfunction (2-6 hr), late organ dysfunction (24-48 hr), sub-clinical DIC, a prolonged anemia, and a 29% mortality between 48 and 72 hr. J Biol Chem, 1991 Jul 5, 266(19), 12536 - 43 Interactions of plasmid-encoded replication initiation proteins with the origin of DNA replication in the broad host range plasmid RK2; Perri S et al.; The TrfA proteins, encoded by the broad host range plasmid RK2, are required for replication of this plasmid in a variety of Gram-negative bacteria . Two TrfA proteins, 33 and 44 kDa in molecular mass (designated TrfA-33 and TrfA-44, respectively), are expressed from the trfA gene of RK2 through the use of two alternative in-frame start codons within the same open reading frame . The two proteins have been purified from Escherichia coli to near homogeneity as a mixture of wild-type TrfA-44/33, as TrfA-33 alone and as a functional variant form of TrfA-44, designated TrfA-44(98L), which contains a leucine in place of the TrfA-33 methionine start codon . Cross-linking experiments demonstrated that TrfA-33 can multimerize in solution . By using gel mobility shift and DNase I footprinting techniques the binding properties of TrfA-33, TrfA-44(98L), and TrfA-44/33 to the origin of replication of plasmid RK2 were analyzed . All three protein preparations were able to bind very specifically to the cluster of five direct repeats (iterons) contained in the minimal origin of replication . Each protein preparation produced a ladder of TrfA/minimal oriV complexes of decreasing electrophoretic mobility . The DNase I protection pattern on the five iterons was identical for all three protein preparations and extended from the beginning of the first iteron to 5 base pairs upstream of the fifth iteron . Studies on the affinity of the proteins for DNA fragments containing one, two, or all five iterons of the origin revealed a strong preference of TrfA protein for DNA containing at least two iterons . To study the stability of TrfA.DNA complexes, association and dissociation rates of TrfA-33 and DNA fragments with one, two, or five iterons were measured . This analysis showed that unlike complexes involving two or five iterons the TrfA/one iteron complexes were highly unstable, suggesting some form of cooperativity between proteins or iterons in the formation of stable complexes and/or the requirement of specific sequences bordering the iterons at the RK2 origin of replication for the stabilization of TrfA/DNA complexes. J Bacteriol, 1991 Jul, 173(14), 4503 - 9 Tet protein domains interact productively to mediate tetracycline resistance when present on separate polypeptides; Rubin RA et al.; Both domains, alpha and beta, of the cytoplasmic membrane-localized Tet proteins encoded by the tet gene family (classes A through E) are required for resistance to tetracycline (Tcr) in gram-negative bacteria . Two inactive proteins, each containing a mutation in the opposite domain, are capable of complementation to produce Tcr . Similarly, inactive hybrid proteins expressed by interdomain gene hybrids constructed between tet(B) and tet(C) {tet(B) alpha/(C) beta and tet(C) alpha/(B) beta} together produce significant Tcr via trans complementation (R.A . Rubin and S . B . Levy, J . Bacteriol . 172:2303-2312, 1990) . A derivative of tet(B) was constructed to express the two domains of Tet(B) as separate polypeptides, neither containing intact the central, hydrophilic interdomain region . Cells harboring this tet(B) mutant expressed Tcr at about 20% the level conferred by intact tet(B) . As expected, no detectable amount of a full-length Tet protein was expressed . A polypeptide corresponding to the alpha domain was observed . Interdomain hybrids between tet(B) and tet(C) containing a frameshift at the fusion junction, designed to result in expression of each of the four domains on separate polypeptides, showed trans complementation without production of detectable full-length proteins . Levels of Tcr were greater than or equal to those previously observed in complementations using full-length hybrid proteins . These results strongly suggest that polypeptides harboring individual alpha and beta domains, lacking an intact interdomain region, can interact productively in the cell to confer Tcr. Infect Immun, 1991 Jul, 59(7), 2505 - 7 The heat-modifiable outer membrane protein of Actinobacillus actinomycetemcomitans: relationship to OmpA proteins; Wilson ME; The outer membrane of Actinobacillus actinomycetemcomitans contains a 29-kDa protein which exhibits heat modifiability on sodium dodecyl sulfate-polyacrylamide gels and represents a major target for immunoglobulin G antibody in sera of periodontitis patients colonized by this organism . In the present study, the N-terminal amino acid sequence of the 29-kDa outer membrane protein was determined and compared with reported sequences for other known proteins . The heat-modifiable outer membrane protein of A . actinomycetemcomitans was found to exhibit significant N-terminal homology with the OmpA proteins of other gram-negative bacteria . Moreover, this protein reacted with antiserum raised against the purified OmpA protein of Escherichia coli K-12 . Whether the heat-modifiable OMP of A . actinomycetemcomitans also shares functional properties of OmpA proteins, particularly with respect to bacteriophage receptor activity, is presently under investigation. Res Microbiol, 1991 Jul-Aug, 142(6), 705 - 10 Diversity of the mechanisms of resistance to beta-lactam antibiotics; Frere JM et al.; The sensitivity of a bacterium to beta-lactam antibiotics depends upon the interplay between 3 independent factors: the sensitivity of the essential penicillin-binding enzyme(s), the quantity and properties of the beta-lactamase(s) and the diffusion barrier that the outer-membrane of Gram-negative bacteria can represent . Those three factors can be modified by mutations or by the horizontal transfer of genes or portions of genes. DICP, 1991 Jul-Aug, 25(7-8), 778 - 83 Human monoclonal antibody against endotoxin; Zarowitz BJ; Little progress has been made over the past several years in the treatment of gram-negative bacteremia and septic shock . Advances in biotechnology have led to the development of human monoclonal antibody against endotoxin (HA-1A), a toxic mediator of the septic response . HA-1A is an immunoglobulin M antibody to the lipid A component of the endotoxin molecule . It distributes into an apparent volume of distribution 10-20 percent larger than plasma volume and has a circulating half-life of 16.0 hours . In a major, multicenter, double-blind trial of HA-1A 100 mg administered intravenously versus placebo, mortality was greatly reduced in HA-1A recipients with gram-negative bacteremia . Increased survival was noted early and was sustained throughout the 28-day study period in patients with and without shock at the time of enrollment . HA-1A has an excellent safety profile; thus far only two minor hypersensitivity reactions and no drug interactions have been reported . Based on currently available information, the release of HA-1A as adjunct therapy for patients with gram-negative bacteremia with or without shock represents a significant therapeutic advance . Investigations are underway to define the optimal dose of HA-1A and its duration of action . Comparative trials between HA-1A and competitive products are necessary. DICP, 1991 Jul-Aug, 25(7-8), 741 - 2 Stability of ceftriaxone sodium in peritoneal dialysis solutions; Nahata MC; Continuous ambulatory peritoneal dialysis is used commonly in patients with endstage renal disease . Infection is the most frequent complication of this dialysis . To treat certain infections caused by gram-negative microorganisms, ceftriaxone sodium may be added to the peritoneal dialysate fluid . No data are available, however, about ceftriaxone's stability at various temperatures in dialysate solutions containing dextrose 1.5 and 4.25% . The objective of this study was to determine the stability of ceftriaxone in dialysis solutions containing dextrose 1.5 and 4.25% over 14 days at 4 degrees C, 5 days at 23 degrees C, and 24 hours at 37 degrees C . Ceftriaxone 500 mg was added to 36 dialysate bags (500 mL); six bags of each of two dextrose concentrations were stored at each of the three temperatures . The samples were collected at 0, 3, 7, 10, and 14 days at 4 degrees C; 0, 1, 2, and 5 days at 23 degrees C; and 0, 6, 12, and 24 hours at 37 degrees C . Ceftriaxone was measured by a specific, stability-indicating HPLC method . A clinically significant loss of potency was defined as a greater than ten percent decrease from its initial concentration . The mean ceftriaxone concentration was 90 percent or more of the initial concentration for 14 days at 4 degrees C, 24 hours at 23 degrees C, and 6 hours at 37 degrees C . Thus, ceftriaxone can be stored in dialysate solutions for 14 days under refrigeration, 24 hours at room temperature, and 6 hours at body temperature. Mol Microbiol, 1991 Jul, 5(7), 1599 - 606 Regulation of capsular polysaccharide synthesis in Escherichia coli K12; Gottesman S et al.; Synthesis of the capsular polysaccharide colanic acid in Escherichia coli K12 is regulated by a complex network of regulatory proteins . This regulation is expressed at the level of transcription of the cps (capsular polysaccharide synthesis) genes . Two positive regulators, RcsA and RcsB, are necessary for maximal capsule expression . The availability of RcsA is normally limited because the RcsA protein is rapidly degraded by the Lon ATP-dependent protease . Therefore Lon acts, indirectly, as a negative regulator of capsule synthesis . The sequence predicted for RcsB suggests that it is the effector component of a two-component system; a protein with homology to sensors, RcsC, also plays a role in capsule regulation . We propose a model for capsule synthesis in which RcsA interacts with RcsB to stimulate transcription of the cps genes . The mechanism of regulation of colanic acid synthesis in E . coli may apply to other capsules in a variety of Gram-negative bacteria. Exp Lung Res, 1991 Jul-Aug, 17(4), 743 - 61 In vivo effects of endotoxin on nasal epithelial mucosubstances: quantitative histochemistry; Harkema JR et al.; Airway inflammation induced by gram-negative bacteria is often characterized by an influx of neutrophils and hypersecretion of mucus . The purpose of this study was to determine how endotoxin, a component of gram-negative bacteria and a chemotaxinogen for neutrophils, affects the amount of stored intraepithelial mucosubstances in the rat nasal airway . Rats were intranasally instilled, once a day for 3 days, with endotoxin or saline (controls) . Before the first and third instillation, half of the animals were depleted of circulating blood neutrophils by administering a rabbit anti-rat neutrophil antiserum . Rats were sacrificed 6 or 24 h after the last instillation . Nasal tissues were processed for light microscopy and histochemical detection of stored intraepithelial mucosubstances . The numbers of nasal epithelial cells and intraepithelial neutrophils per millimeter of basal lamina in the anterior nasal septum and the amounts of intraepithelial mucosubstances in the same nasal tissue were determined by image analysis . We did not observe a neutrophil influx in the nasal tissues of neutrophil-depleted rats at 6 or 24 h after the last endotoxin instillation; however, we did observe a significant increase in intraepithelial mucosubstances, compared to saline-instilled controls . In contrast, nonneutrophil-depleted animals had a marked neutrophilic influx and a concomitant decrease in stored mucosubstances, compared to saline-instilled controls . There was no significant difference in the number of nasal epithelial cells per millimeter of basal lamina among any of the experimental groups . These results indicate (1) that endotoxin induces an increase in the amount of intraepithelial mucosubstances only when intraepithelial neutrophils are absent, and (2) that the endotoxin-induced, neutrophil influx probably triggers mucous hypersecretion. J Submicrosc Cytol Pathol, 1991 Jul, 23(3), 447 - 55 Rickettsiae and giant lysosomes in the testes of Temnocephala novaezealandiae (Platyhelminthes: Temnocephaloidea); Williams JB; Rickettsiae are concentrated in the testes of Temnocephala novaezealandiae, where they occupy the cytoplasm of spermatogenetic stages and the testis epithelia . They have gram negative ultrastructural characteristics and are surrounded by clear zones which are not membrane-limited; indented mitochondria are associated with the clear zones . Propagation occurs by simple division . Extensions of the testis epithelium envelop cloned groups of spermatocytes, spermatids and spermatozoa . Heterophagosomes isolating unmodified rickettsiae, and giant lysosomes enclosing bacteria in advanced stages of degradation, are contained within the epithelial processes . Rickettsiae and large lysosomes were found also in testes of Troglocaridicola mrazeki, a scutariellid . Peririckettsial lucid zones are interpreted as areas of histopathy where host cytoplasm has been catabolized by bacterial enzymes . The rickettsiae evidently are true parasites, although they have no apparent harmful effect on the general condition of their hosts . Digestion of bacteria in lysosomes may provide nutrients for spermatogenetic stages . Transmission of rickettsiae to juvenile temnocephalids does not occur via the spermatozoa. Am J Med, 1991 Jul, 91(1), 23 - 9 High circulating levels of interleukin-6 in patients with septic shock: evolution during sepsis, prognostic value, and interplay with other cytokines . The Swiss-Dutch J5 Immunoglobulin Study Group; Calandra T et al.; PURPOSE AND PATIENTS: We measured the serum concentrations of interleukin-6 (IL-6) in 70 patients with established septic shock caused predominantly by gram-negative bacteria . The aims of the study were to determine whether and for how long IL-6 was detectable in the circulation of these patients, to assess whether IL-6 levels were associated with patients' outcomes, and, finally, to examine the interplay between IL-6, tumor necrosis factor (TNF), interleukin-1 beta (IL-1 beta), and interferon-gamma (IFN-gamma) . RESULTS: IL-6 was detected in 64% of the patients at study entry but in only 18% on Day 1 and 2% on Day 10 . Serum levels of IL-6 were higher (median: 3.5 ng/mL, range: less than 0.1 to 305 ng/mL) in patients dying of fulminant septic shock than in those surviving (median: 0.5 ng/mL, range: less than 0.1 to 135 ng/mL; p = 0.003) or in those with a transient reversal of shock but who ultimately died of a relapse of shock (median: less than 0.1 ng/mL, range: less than 0.1 to 12.5 ng/mL; p = 0.005) . However, no cutoff values of IL-6 confidently predicted the outcome of an individual patient . The serum concentrations of IL-6 measured at study entry correlated with the duration of survival (r = -0.51, p = 0.004) and with the levels of TNF-alpha (r = 0.53; p less than 0.0001) but not with the levels of either IL-1 beta (r = 0.01, p = 0.90) or IFN-gamma (r = 0.06, p = 0.60) . CONCLUSIONS: These results indicate that circulating levels of IL-6 are detectable in a majority of patients with gram-negative septic shock . Concentrations of IL-6 peaked near the onset of shock and rapidly decreased to undetectable levels within approximately 24 hours in most patients . Levels of IL-6 measured at study entry correlated with levels of TNF and with patients' outcomes . Yet, IL-6 does not appear to be a clinically useful laboratory test for predicting the outcome of an individual patient. Clin Microbiol Rev, 1991 Jul, 4(3), 286 - 308 The tribe Ehrlichieae and ehrlichial diseases; Rikihisa Y; The tribe Ehrlichieae consists of gram-negative minute cocci that are obligate intracellular parasites classified in the family Rickettsiaceae . Although ehrlichial organisms have been observed in leukocytes for many years, only a few species have been cultured in quantities sufficient for biochemical and molecular analyses . Recents studies on 16S-rRNA sequence analysis and energy metabolism showed that the genus Ehrlichia is closely related to the genus Rickettsia . There is, however, no antigenic cross-reactivity between these genera . Ehrlichial organisms cause a disease called "ehrlichiosis," a noncontagious infectious disease known to be transmitted by a tick in several cases and by a fluke in one case . Ehrlichia spp . infect dogs, ruminants, horses, and humans . Recently, two new ehrlichial diseases, Potomac horse fever and human ehrlichiosis, were discovered in the United States . The etiologic agent of Potomac horse fever, Ehrlichia risticii, is closely related to the known human pathogen Ehrlichia sennetsu . The etiologic agent of human ehrlichiosis is related to Ehrlichia canis, a canine pathogen . In contrast to the genus Rickettsia, members of the tribe Ehrlichieae reside primarily in the cytoplasmic vacuoles of monocytes or granulocytes and cause hematologic abnormalities, lymphadenopathy, and other pathologic changes in the host . However, the actual mechanisms whereby Ehrlichia spp . infect leukocytes, multiply in them, and produce various forms of systemic disease have not been defined . Depending on the ehrlichial species involved, serologic or direct microscopic observation of stained blood smears is currently used to diagnose ehrlichial disease. J Invertebr Pathol, 1991 Jul, 58(1), 75 - 81 Extracellular giant rickettsiae associated with bacteria in the gill of Crassostrea gigas (Mollusca, Bivalvia); Azevedo C et al.; Extracellular giant rickettsiae closely associated with bacteria with a Gram-negative type wall are reported among the basal insertions of the cilia of the gill epithelium of the oyster Crassostrea gigas (Mollusca, Bivalvia) from the north of Spain . These rickettsiae are extremely pleomorphic cells with a maximum 9 microns length . The internal elements are ribosome-like particles and DNA strands are distributed in some light areas . Some rickettsial cells show one to two vacuole-like dense inclusions formed by curved concentric bands approximately 4 nm thick separated by an approximately 5-nm light space (myelin-like bodies) . Numerous bacteria are closely associated with the rickettsiae in the surrounding zone . The cytopathic effects of this association seemed to give rise to the epithelial lysis and concomitant disappearance of the apical microvilli and cilia and the consequent destruction and disintegration of the gill epithelial cells, where these rickettsiae live in close proximity . This is believed to be the first description of extracellular giant pathogenic rickettsiae of these oyster species. J Laryngol Otol, 1991 Jul, 105(7), 582 - 3 Parapharyngeal space melioidosis in a diabetic; Elango S et al.; Pseudomonas pseudomallei, a gram negative organism causing melioidosis, is found in tropical and subtropical regions . It may manifest as a pulmonary lesion, osteomyelitis, soft tissue abscesses, abscesses in various organs or in septicaemic form . Melioidosis of the parapharyngeal space has not been reported so far . A case of melioidosis of the parapharyngeal space which was successfully treated by drainage and prolonged antibiotic therapy is reported here . Melioidosis should be suspected in severe forms of deep neck space infection, especially if the patient comes from an endemic area. J Periodontal Res, 1991 Jul, 26(4), 308 - 13 Black-pigmenting gram-negative bacteria in periodontal disease . II . Screening strategies for detection of P . gingivalis; Mombelli A et al.; The purpose of this analysis was to evaluate the feasibility of detecting P . gingivalis using selected sites and to indicate increased proportions of this organism in periodontitis patients . In 10 patients suffering from moderate to advanced periodontal disease, separate microbiological samples were taken from the mesial, buccal, distal and oral (lingual or palatal) aspects of every tooth . This yielded a total of 927 microbiological samples, 84 to 102 per patient . Three distinct patterns of distribution and relative proportion of P . gingivalis were recognized . In one group of patients, the organism was not cultured . In a second group, few positive sites with low proportions of P . gingivalis were present . A third group of patients yielded high frequencies and proportions of P . gingivalis . The number of samples necessary to diagnose the presence of P . gingivalis at a 95% confidence level varied considerably between the three groups . In 4 patients, sampling 4 randomly selected sites was sufficient, while in the remaining 3 positive patients, 25 or more samples were required to detect the organism with equal certainty . Seven different protocols for multiple subgingival sampling were studied . When considering the number of samples needed to detect the presence of P . gingivalis and to estimate the highest proportion of this organism, selection of the deepest pocket in each quadrant was the most efficient method of sampling. J Periodontal Res, 1991 Jul, 26(4), 301 - 7 Black-pigmenting gram-negative bacteria in periodontal disease . I . Topographic distribution in the human dentition; Mombelli A et al.; The purpose of this study was to determine the distribution of black-pigmenting Gram-negative bacteria in the dentition of periodontitis patients and to examine differences in the microbial composition of samples taken from a series of adjacent sites . Separate subgingival samples were taken from the mesial, buccal, distal and oral aspects of every tooth in 10 subjects . Thus, a total of 927 sites, 84 to 102 per patient, were scored clinically and sampled microbiologically . P . intermedia and P . melaninogenica were found in all subjects . P . gingivalis was found in 7 . The organisms tended to be distributed unevenly, giving the impression of clusters of positive samples in certain areas of the dentition . 77% of all samples positive for P . gingivalis were also P . intermedia-positive . Premolars had lower frequencies and mean proportions of P . gingivalis than incisors and molars . In the premolar and molar region, frequencies and mean proportions of P . gingivalis increased with more posterior location . While frequencies indicated a similar topographic distribution of P . intermedia the mean proportions of this organism were more consistent at different locations . Based on a logistic regression model, it was estimated that the probability of detecting P . gingivalis was 34 times higher in any site which had at least 1 P . gingivalis-positive neighboring site . For P . intermedia any site with at least 1 P . intermedia-positive neighboring site had a chance 2.4 times higher of harboring the organism as well . The highest chance of detecting P . gingivalis and P . intermedia existed in deep, oral pockets of molars, which bled upon sampling. J Med Assoc Thai, 1991 Jul, 74(7), 288 - 92 Efficacy of dosage schedule for rational dosage prescribing of gentamicin; Thamlikitkul V et al.; In our pilot study of 30 patients who were on gentamicin, the adequate peak level (5-10 mg/dl) was found in 27 per cent, trough level (less than 2 mg/dl) in 67 per cent and both peak and trough level in only 10 per cent . We have several reasons to believe that it is due to inappropriate dosage prescribing . The objective of the study is to test the efficacy of using a recommended dosage schedule for rational dosage prescribing of gentamicin . All medical residents were invited to attend a 2-hour session on gentamicin pharmacokinetics . The problems and the use of recommended dosage schedule were extensively discussed . Then serum gentamicin levels were re-monitored by Fluorescence Polarization Immunoassay (TDx) . Of 73 gentamicin recipients, 39 (53%, C gr.) were given at the correct dosage according to the schedule and 34 (47%, IC gr) were given incorrectly . The characteristics of the patients in both groups were not different . The appropriate peak, trough, peak and trough levels in C gr were 87, 80, 67 per cent respectively compared with 24, 80 and 9 per cent in the IC group, p less than 10(-4) for peak, peak and trough . The incidence of nephrotoxicity was not different between the two groups . The patients' outcomes were difficult to assess because most of the patients received antibiotic combinations . However, case fatality of documented gram-negative infection tended to be less in the C group . It is concluded that dosage schedule can improve rational dosage prescribing of gentamicin . Most of the patients given gentamicin may not need monitoring.(ABSTRACT TRUNCATED AT 250 WORDS) Rev Infect Dis, 1991 Jul-Aug, 13(4), 666 - 87 University of California/Davis Interdepartmental Conference on gram-negative septicemia; Young LS et al.; Gram-negative septicemia remains one of the most serious forms of hospital-acquired infection . The most consistently virulent component of the gram-negative lipopolysaccharide (endotoxin) appears to be lipid A . Elucidation of the structure-function relationships of lipid A and the biochemical configurations required for endotoxicity makes possible the design of lipopolysaccharide antagonists and/or the production of poly- or monoclonal antibodies that may abrogate the biologic effects of endotoxin . The mechanisms of activity of lipopolysaccharide and the pathophysiologic events it triggers are now better understood than in the recent past . Lipid A triggers the release of mediators such as cachectin (tumor necrosis factor), thereby initiating a cascade of potentially lethal events . Although recent studies indicate no routine role for corticosteroids in gram-negative septic shock or acute respiratory distress syndrome, considerable progress has been made in the development of effective antibiotics . Recent studies of septicemia in neutropenic patients show survival rates significantly higher than those reported more than two decades ago. Am Rev Respir Dis, 1991 Jul, 144(1), 202 - 7 Characteristics of aerobic gram-negative bacteria colonizing critically ill patients; Donaldson SG et al.; Adherence of gram-negative bacteria (GNB) to epithelial surfaces is important for GNB colonization to occur . Pili, rodlike structures projecting from the outer membrane of GNB, and GNB surface hydrophobicity have been shown to enhance GNB adherence . We investigated the types of pili and the hydrophobicity of aerobic GNB colonizing the stomach, oropharynx, and trachea of critically ill patients . Piliation and hydrophobicity of oral, tracheal, and gastric GNB were compared with that of commensal GNB isolated from patients' rectums . Significantly more oropharyngeal than rectal GNB were piliated, and the most common type of pili present was type 1, or mannose-sensitive pili . Mannose-resistant and P pili were present less often, and no colonizing GNB had S pili . Colonizing GNB were hydrophilic rather than hydrophobic, and no differences in hydrophobicity were noted between colonizing GNB and rectal isolates . Our results suggest that pili may be important for oropharyngeal GNB colonization. J Bacteriol, 1991 Jul, 173(13), 4195 - 202 Fragmentation of Escherichia coli type 1 fimbriae exposes cryptic D-mannose-binding sites; Ponniah S et al.; Cells of the gram-negative bacterium Escherichia coli are able to attach to various host cells by means of a mannose-specific adhesin associated with type 1 fimbriae . Here we show that fragmentation of type 1 fimbriae by freezing and thawing results in increased mannose-binding activity as demonstrated by increased hemagglutination, increased stimulation of human lymphocyte proliferation, and increased binding of the mannose-containing enzyme horseradish peroxidase . Increased activity in all three assays was mannose sensitive and was not exhibited by FimH- mutant type 1 fimbriae lacking the adhesin . Scatchard analysis of the data from peroxidase binding assays showed that unfrozen and frozen fimbriae contain binding sites displaying two classes of affinity . Frozen and thawed fimbriae expressed an increase in the number of high-affinity binding sites . These results show that fragmentation of the fimbrial structure exposes cryptic mannose-binding activity associated with type 1 fimbriae, presumably that of internally located adhesin molecules . Our data support earlier observations that adhesin moieties of type 1 fimbriae are located both at the tips and at intervals along the length of the fimbriae . In addition, our data suggest that only the adhesin moieties that are located at the fimbrial tips are functional in binding mannose . Adhesins located along the length of the fimbriae have their mannose-binding activity buried within the fimbrial structure and hence are not functional . We propose an updated model for the structure of type 1 fimbriae that is in agreement with the above observations. FEMS Microbiol Lett, 1991 Jul 1, 65(3), 261 - 4 An improved aminoglycoside resistance gene cassette for use in gram-negative bacteria and Streptomyces; Denis F et al.; A cloning cassette, carrying a modified amino-glycoside resistance gene (neo) from transposon Tn5 was constructed . Three restriction sites internal to the neo gene were eliminated by in vitro mutagenesis, allowing their use in designing new cloning vectors . The original, suboptimal transcription promoter was replaced with a synthetic sequence corresponding to the consensus for E . coli and Streptomyces promoters . The cassette has numerous restriction sites for easy subcloning of the promoter, the coding sequence or the whole gene. Eur J Pediatr, 1991 Jul, 150(9), 665 - 8 Vitamin D dependent rickets type II with myelofibrosis and immune dysfunction; Walka MM et al.; We present a new patient with vitamin D dependent rickets type II . A 20-month-old Arabian boy whose parents are first cousins showed florid rickets, myelofibrosis and recurrent septicaemia . In addition to absent specific binding for 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) . 25-Hydroxyvitamin D3-24-hydroxylase activity could not be induced in cultured fibroblasts . The patient did not respond to 99 micrograms 1,25(OH)2D3 per day, but skeletal and haematological abnormalities improved with daily infusion of 100 mg/kg calcium, as serum parathyroid hormone levels fell to normal values . At the age of 7 years, he died from pneumonia . The improvement of haematological abnormalities with calcium infusions but not with 1.25(OH)2D3 suggests a pathogenetic relationship of myelofibrosis and hyperparathyroidism . Having anti-lipid A IgM antibody titres up to 1:10.000 after Gram negative septicaemias, the patient never produced corresponding IgG antibodies . His neutrophil chemotaxis was persistently reduced to 57% +/- 3% of age-matched controls (P less than 0.028) . The patient showed two pathological immune functions considered to contribute to the well-known susceptibility to infection in rickets. J Bacteriol, 1991 Jul, 173(14), 4493 - 502 Characterization of the nonenzymatic chloramphenicol resistance (cmlA) gene of the In4 integron of Tn1696: similarity of the product to transmembrane transport proteins; Bissonnette L et al.; Integrons constitute a novel family of DNA elements which evolved by site-specific integration of discrete units between two conserved segments . On the In4 integron of Tn1696, a precisely inserted gene cassette of 1,549 bp conferring nonenzymatic chloramphenicol resistance (cmlA) is present between the streptomycin-spectinomycin resistance (aadA2) gene cassette and the 3'-conserved segment of the integron . In this study, we present the nucleotide sequence of the cmlA gene cassette of Tn1696, show its similarity to bacterial efflux systems and other transport proteins, and present evidence for alterations that its expression exerts on bacterial membranes . The cmlA gene cassette apparently carries its own promoter(s), a situation that has not heretofore been observed in the integrons of multiresistance plasmids and transposons of gram-negative bacteria . One or more of these promoters were shown to be functionally active in expressing a cat marker gene from promoter-probe vectors . The putative CmlA polypeptide appears to provoke a reduction of the content of the major porins OmpA and OmpC. Infect Immun, 1991 Jul, 59(7), 2252 - 8 Outer membrane protein A (OmpA) contributes to serum resistance and pathogenicity of Escherichia coli K-1; Weiser JN et al.; We examined whether outer membrane protein A (OmpA) contributes to gram-negative pathogenesis by determining the effect of mutagenesis of ompA in a virulent Escherichia coli K-1 isolate . An OmpA mutant was generated by insertion of the transposon TnphoA, which was genetically modified to increase the efficiency of its delivery by conjugation . The mutant was less virulent than its parent strain in two models of E . coli K-1 infection . Equal inocula of the OmpA+ and OmpA- strains fed to neonatal rats resulted in a sevenfold-greater incidence of bacteremia at 72 h from the OmpA+ strain . The lethal effect of the OmpA- mutant was significantly less than that of the OmpA+ parent strain when inoculated onto the chorioallantoic membrane of 10-day embryonated chick eggs . There was, however, no difference between strains in growth characteristics under physiologic conditions, either in rat serum or in unembryonated chick eggs . In the presence of a 10-day chick embryo, there was a 10-fold increase in the survival and growth of the OmpA+ strain . Correction of the mutation in ompA with an E . coli K-12 ompA gene restored a level of virulence equivalent to that of the parent strain . The ompA mutant was more sensitive to the bactericidal effect of pooled human serum by the classical pathway of complement activation . These results suggest that OmpA contributes to E . coli K-1 pathogenesis by a mechanism which may involve increased serum resistance. Oral Surg Oral Med Oral Pathol, 1991 Jun, 71(6), 689 - 95 Salivary secretion rate, yeast cells, and oral candidiasis in patients with acute leukemia; Wahlin YB; Stimulated salivary secretion rate was repeatedly determined in 29 patients with acute leukemia during two periods of cytotoxic treatment in myelosuppressive doses . For comparison, the salivary secretion rate was studied in 83 healthy persons and in three other groups of hospitalized patients without malignant disorders . At the start of cytotoxic treatment the secretion rate in the patients with leukemia was lower than in healthy persons . The rate fell significantly after 1 to 3 days and later rose to the level seen in the healthy persons . Several interacting factors may have contributed to the decrease in salivary secretion rate, but the most important factor was probably the use of antiemetic drugs during the first 3 days of the study periods . No relationship was found between salivary secretion rate and the number of gram-negative rods found in the mouth . Patients with low salivary secretion rates had high numbers of yeast cells and more often oral candidiasis. Am J Pathol, 1991 Jun, 138(6), 1485 - 96 The intratracheal administration of endotoxin and cytokines . I . Characterization of LPS-induced IL-1 and TNF mRNA expression and the LPS-, IL-1-, and TNF-induced inflammatory infiltrate; Ulich TR et al.; Endotoxin (LPS), one of the major proinflammatory constituents of the cell walls of gram-negative bacteria, induces alveolar macrophages to express interleukin-1 (IL-1) and tumor necrosis factor (TNF) messenger RNA (mRNA), peaking at 1 hour in vitro . Intratracheal injection of LPS induces IL-1 and TNF mRNA expression in vivo in whole-lung RNA preparations . Interleukin-1 mRNA is not constitutively detected . In the case of TNF, however, a constitutively-expressed hybridization band is noted at 1.6 kb, whereas the LPS-induced hybridization band is noted at approximately 1.95 kb . Intratracheal injection of LPS induces an intra-alveolar inflammatory reaction composed of a neutrophilic exudate, peaking at 6 to 12 hours, a monocytic exudate peaking at 24 hours, and a lymphocytic exudate peaking at 48 hours, as quantitated by bronchoalveolar lavage . Intratracheal injection of IL-1 recapitulates the kinetics and relative magnitudes of the acute neutrophilic and chronic monocytic and lymphocytic inflammatory sequence . Intratracheal injection of TNF also induces an acute intraalveolar neutrophilic exudate, but TNF is much less potent of an inflammatory stimulus than IL-1 . The effects of recombinant IL-1 and TNF are not due to LPS contamination, as shown by abrogation of the cytokines' inflammatory activity by boiling . In conclusion, LPS induces IL-1 and TNF mRNA expression in vitro in alveolar macrophages and in vivo in pulmonary tissue, and intratracheal injection of IL-1 and TNF recapitulates the LPS-induced pulmonary inflammatory sequence, strongly supporting the hypothesis that these cytokines play an important in vivo role in the pathogenesis of gram-negative bacterial pneumonia. Surgery, 1991 Jun, 109(6), 698 - 705 Tumor necrosis factor and interleukin-1 protection against the lethal effects of tumor necrosis factor; Sheppard BC et al.; Based on the hypothesis that tumor necrosis factor (TNF) causes the lethality of gram-negative sepsis and previous work of tolerance to the lethal effects of TNF induced by repetitive exposure to sublethal intraperitoneal doses of human recombinant (r) TNF, we studied the protective role of a single sublethal intravenous dose of either rTNF (100 micrograms/kg) or recombinant interleukin-1 (rIL-1; 10(5) units/kg) or both before a subsequent lethal intravenous dose of rTNF (800 to 1000 micrograms/kg) in C3H/HEN mice . Mice were treated with a single intravenous dose of saline, rTNF, rIL-1 or both cytokines and challenged within 2 hours to 10 days with a lethal dose of rTNF . Mice treated with rTNF showed significant protection against the lethal effects of TNF when the treatment dose was given only 2 hours before the lethal dose, but maximal protection required a 24-hour interval and lasted as long as 8 days . The treatment dose of rTNF was toxic, and it resulted in occasional treatment deaths . Mice treated with rIL-1 showed maximal protection when treatment was given only 2 hours before challenge and protection lasted for 8 days . No toxicity was apparent secondary to IL-1 treatment . The combination of rIL-1 and rTNF was not as effective as either cytokine alone . The results suggest that rTNF or rIL-1 may be clinically useful in the prevention and treatment of sepsis lethality by the induction of tolerance to the lethal effects of TNF . The more promising cytokine appears to be rIL-1 because it has less toxicity and more rapid induction of full therapeutic effectiveness. Toxicol Appl Pharmacol, 1991 Jun 1, 109(1), 51 - 9 Increased endotoxin sensitivity following T-2 toxin treatment is associated with increased absorption of endotoxin; Taylor MJ et al.; Oral exposure to T-2 Toxin (T-2) in experimental animals results in a syndrome similar to that observed in endotoxemia . Endotoxins are lipopolysaccharide, outer-membrane components of gram-negative bacteria which induce acute, inflammatory responses . In the present study, several aspects of endotoxin pathophysiology were investigated in mice following simultaneous exposure to T-2 and endotoxin, including mortality, hypothermia, tumor necrosis factor-alpha (TNF-alpha) and corticosterone production, and thymic weight . The disposition of endotoxin was also assessed, Acute, simultaneous exposure to T-2 (4 mg/kg, po) and endotoxin (3 micrograms/mouse, ip) resulted in increased mortality, hypothermia, TNF-alpha production, and thymic atrophy compared to treatment with either T-2 of endotoxin alone . Pretreatment of mice with endotoxin, a regime that renders the animals resistant to the effects of endotoxin, reduced many endotoxin effects in animals treated simultaneously with T-2 and endotoxin . Upon further investigation, it was observed that T-2 increased the absorption rate of endotoxin: as the peak height of serum endotoxin increased, the time-to-peak decreased, and the area under the curve was unchanged in animals treated simultaneously with T-2 and endotoxin . It was concluded that increased endotoxin absorption accounted for the increases in mortality, hypothermia, and TNF-alpha associated with T-2 exposure. Q J Med, 1991 Jun, 79(290), 517 - 25 Perspectives in multiple myeloma: survival, prognostic factors and disease complications in a single centre between 1975 and 1988; Rayner HC et al.; One hundred and forty-one patients with multiple myeloma, diagnosed at the City Hospital, Nottingham between January 1975 and October 1986, were followed until death or for at least two years in a retrospective study . Overall median survival was 25 months, with no significant improvement occurring during the study period; increasing age, ESR and serum creatinine concentration at diagnosis were independent predictors of shortened survival . Renal impairment developed in 56 per cent of patients but only 7 per cent died of renal failure . At least one episode of infection occurred in 55 per cent of patients, most commonly in the first month . There was a significant rise in the overall incidence of infection and in the proportion caused by Gram-negative bacteria during the study period . Raised serum urea and low haemoglobin concentrations at diagnosis were independent risk factors for subsequent infection . Infection was associated with 2.75-fold increased risk of death, independent of other risk factors . Prevention of infection is an important aim for improvements in the survival of patients in multiple myeloma. J Antimicrob Chemother, 1991 Jun, 27(6), 707 - 12 Cloning of the type Ib trimethoprim-resistant dihydrofolate reductase gene and preparation of a specific biotinylated DNA probe; Qumsieh MJ et al.; A 3.0-kb PstI/HindIII fragment encoding the type Ib trimethoprim-resistant dihydrofolate reductase (DHFR) was cloned into pUC18 . Following successive subcloning, the type Ib DHFR gene was identified within a 500 bp HincII fragment . The 500 bp fragment was purified, biotinylated and tested for its suitability as a specific DNA probe in non-isotopic hybridisation experiments with standard plasmids carrying genes for the available known Gram-negative DHFR types . Under conditions of high stringency the probe was specific for the type Ib gene and hence will be useful for monitoring the spread of this particular trimethoprim resistance gene. J Bacteriol, 1991 Jun, 173(11), 3591 - 6 Acyl-acyl carrier protein specificity of UDP-GlcNAc acyltransferases from gram-negative bacteria: relationship to lipid A structure; Williamson JM et al.; Lipid A, the component of lipopolysaccharide that provides the membrane anchor of the core and O-antigen sugars, is known to contain characteristic R-3-hydroxy fatty acids bound to the 2,2' (N-linked) and 3,3' (O-linked) positions of the glucosamine disaccharide in different gram-negative bacteria . The studies reported here show that it is the acyl-acyl carrier protein specificities of the enzymes UDP-GlcNAc-O-acyltransferase and UDP-3-O-{(R)-3-hydroxyacyl}-GlcN-N-acyltransferase that determine the nature of these fatty acids. J Bacteriol, 1991 Jun, 173(11), 3342 - 55 Behavior of peripheral rods and their role in the life cycle of Myxococcus xanthus; O'Connor KA et al.; Myxococcus xanthus is a gram-negative bacterium with a complex life cycle including a developmental phase in which cells aggregate and sporulate in response to starvation . In previous papers, we have described a heretofore unsuspected layer of complexity in the development of M . xanthus: vegetatively growing cells differentiate into two cell types during development . In addition to the differentiation of spores within fruiting bodies, a second cell type, peripheral rods, arises outside fruiting bodies . The pattern of expression of proteins in peripheral rods is different from that of either vegetatively growing cells or spores, and peripheral rods express a number of recognized developmental markers . In this report, we examine four aspects of the biology of peripheral rods: (i) the influence of nutrients on the proportion of peripheral rods in a population of developing cells, (ii) the capacity of peripheral rods to recapitulate development, (iii) the development of peripheral rods on conditioned medium, and (iv) the ability of peripheral rods to resume growth on low amounts of exogenously added nutrients . The results of these studies suggest that peripheral rods play a significant role in the life cycle of M . xanthus by allowing the exploitation of low amounts or transient influxes of nutrients without the investment of energy in spore germination . The differentiation of vegetatively growing cells into two cell types that differ significantly in biology, shape, and localization within the population has been incorporated into a model of the life cycle of M . xanthus. J Bacteriol, 1991 Jun, 173(11), 3334 - 41 Analysis of Myxococcus xanthus cell types by two-dimensional polyacrylamide gel electrophoresis; O'Connor KA et al.; Myxococcus xanthus is a gram-negative, soil-dwelling bacterium that undergoes development in response to depletion of nutrients . Whereas most cells aggregate into multicellular mounds in which they differentiate into spores, 10 to 20% of the developing cells remain outside fruiting bodies as peripheral rods . We used two-dimensional polyacrylamide gel electrophoresis to analyze the global expression of polypeptides in cells taken from six stages in the life cycle: vegetatively growing cells, cells 15 h after the induction of development, peripheral rods, prespores (sonication-sensitive, aggregated cells), fruiting-body spores (sonication-resistant, aggregated cells) 96 h after the induction of development, and glycerol-induced spores 15 h after induction . Seven hundred sixty-one discrete sample spots (SSPs) were identified among the six gels . Comparisons among the samples revealed that each sample had some unique SSPs, ranging from 0.3% of the 15-h developing cell SSPs to 17.9% of 96-h peripheral rod SSPs . Sixty-eight SSPs were ubiquitously distributed, but the relative amounts of these SSPs varied among the samples . Statistical analyses of the distribution and relative quantities of the SSPs indicate that, within a confidence level of greater than 99.99%, peripheral rods are significantly different from vegetatively growing cells, 15-h developing cells, prespores, fruiting-body spores, and glycerol-induced spores . In fact, among the six samples studied, only 15-h developing cells and glycerol-induced spores were similar to each other within a confidence level of P greater than or equal to 0.05 . These results are consistent with the description of peripheral rods as a distinct developmental cell type. J Bacteriol, 1991 Jun, 173(11), 3318 - 33 Development in Myxococcus xanthus involves differentiation into two cell types, peripheral rods and spores; O'Connor KA et al.; Myxococcus xanthus, a gram-negative bacterium, has a complex life cycle . In response to starvation, most cells in a population participate in the formation of multicellular aggregates (i.e., fruiting bodies) in which cells differentiate into spores . However, some cells do not enter aggregates . In this and the two accompanying reports, the biology and physiology of these nonaggregated cells is examined . A technique to separate aggregated cells from nonaggregated cells was developed; then differentiating cells at stages throughout the course of development were isolated . In this report we (i) describe peripheral rods, those cells which remain outside aggregates after aggregation has ceased in the rest of the population; (ii) document the occurrence of peripheral rods in several wild-type strains; and (iii) characterize the expression of developmentally regulated genes in both aggregated and nonaggregated cells . These studies have shown that myxobacterial hemagglutinin, protein S (Tps), protein S1 (Ops), protein C, and several phosphatase activities are expressed in cell-type-specific patterns . These data demonstrate that peripheral rods constitute a cell type distinct from either vegetatively growing cells or spores . The description of a second, late developmental cell type (in addition to spores) opens an entirely new line of investigation in M . xanthus, i.e., the regulation of the differentiation of vegetatively growing cells into two cell types that differ significantly in biology, shape, and localization within the population. Mol Microbiol, 1991 Jun, 5(6), 1561 - 6 Transformation of Mycobacterium aurum and Mycobacterium smegmatis with the broad host-range gram-negative cosmid vector pJRD215; Hermans J et al.; The transformation of Mycobacterium aurum and Mycobacterium smegmatis with the Gram-negative RSF1010-derived cosmid pJRD215 is described . The plasmid is stably maintained in both species and the antibiotic resistance determinants for kanamycin and streptomycin are expressed . Southern blot analysis shows that rearrangements take place both in M . aurum and in M . smegmatis . The use of pJRD215 in mycobacterial cloning systems is discussed. J Infect Dis, 1991 Jun, 163(6), 1256 - 66 Role of normal serum in the binding of lipopolysaccharide to IgG fractions from rabbit antisera to Escherichia coli J5 and other gram-negative bacteria; Warren HS et al.; Because lipopolysaccharide (LPS) bound to lipoprotein is less active than unbound LPS in multiple assay systems, the binding of radiolabeled LPS to lipoproteins in sera prepared from normal rabbits and rabbits made hyperimmune to Escherichia coli J5 were compared . LPS-lipoprotein binding in hyperimmune sera to E . coli J5 was not greater than that in normal serum as assessed by ultracentrifugation, but more LPS was precipitated from hyperimmune antisera than normal sera under conditions designed to precipitate LPS-lipoprotein complexes with calcium and dextran . Radiolabeled LPS was precipitated by delipidated antisera and fractions of IgG purified by anion exchange chromatography, but the precipitation was dependent on the presence of normal serum in the reaction mixture . These data suggest that a fluid-phase RIA done in the presence of normal serum may facilitate the detection of IgG in antisera raised to E . coli J5 that binds to heterologous smooth LPS. Metabolism, 1991 Jun, 40(6), 585 - 93 Sepsis-induced increases in glucose uptake by macrophage-rich tissues persist during hypoglycemia; Lang CH et al.; The purpose of the present study was to determine how hypoglycemia alters glucose uptake by individual tissues and whether this response is altered by gram-negative infection . A hypermetabolic septic state was produced in catheterized rats by subcutaneous injections of live Escherichia coli . The next morning, animals were infused with saline, somatostatin to produce a euglycemic insulinopenic state (6 mmol/L glucose, 5 microU/mL insulin), or 3-mercaptopicolinate (3-MP) to inhibit gluconeogenesis and produce a hypoglycemic insulinopenic (4.5 or 2 mmol/L glucose, 5 microU/mL insulin) condition . After 140 minutes, {14C}2-deoxyglucose was injected intravenously (IV) to determine in vivo glucose uptake by individual tissues . Sepsis increased whole body glucose disposal (Rd) by 53% under basal euglycemic conditions and this increase resulted from an enhanced rate of glucose removal by liver, spleen, lung, ileum, and skin . Under euglycemic insulinopenic conditions, total glucose Rd decreased in both septic and nonseptic rats as a result of a decreased rate of glucose uptake by muscle . However, because the absolute rate of glucose uptake was still elevated by sepsis, the rate of non-insulin-mediated glucose uptake (NIMGU) was 46% higher in septic rats than in nonseptic animals . Severe hypoglycemia (2 mmol/L) produced a relative insulin deficiency and decreased whole body Rd in both septic and nonseptic animals by 53% to 58%, compared with euglycemic insulinopenic animals . The decrease in blood glucose decreased glucose uptake by all tissues examined, except brain and heart . However, sepsis still increased glucose uptake by liver, spleen, lung, ileum, and skin (25% to 90%), compared with hypoglycemic nonseptic rats.(ABSTRACT TRUNCATED AT 250 WORDS) J Gen Microbiol, 1991 Jun, 137 ( Pt 6), 1425 - 9 Characterization of a beta-lactamase produced by Pseudomonas paucimobilis; Corkill JE et al.; A novel beta-lactamase enzyme produced by a strain of Pseudomonas paucimobilis is described . The enzyme differs from other recorded beta-lactamases from Gram-negative aerobic bacteria . It was constitutive, and had the characteristics of a penicillinase . One single band of beta-lactamase activity at pI 4.6 was seen on iso-electric focusing . The enzyme had a molecular mass of 30 kDa . The beta-lactamase was strongly inhibited by tazobactam, sulbactam and clavulanic acid but not by the thiol residue inhibitors p-chloromercuribenzoate and p-chloromercuriphenylsulphonic acid, or by metallo-enzyme inhibitors . Plasmid DNA was not demonstrable, suggesting that the enzyme was chromosomally encoded. Control Clin Trials, 1991 Jun, 12(3), 395 - 407 Termination of the Department of Veterans Affairs Cooperative Study of steroid therapy for systemic sepsis; Peduzzi P; The Department of Veterans Affairs Cooperative Study Program conducted a randomized, double-masked trial of steroid therapy versus placebo therapy for patients with systemic sepsis from 1983 to 1986 . Treatment was initiated as soon as sepsis was recognized and before results of cultures confirmed infection . The original hypothesis was to test the effect of therapy on short-term (14-day) mortality in patients with gram-negative bacteremia . Because therapy had to begin before culture results were available, all septic patients had to be enrolled . Consequently, the study was modified to evaluate therapy in all patients with sepsis, and by post-stratification in those with gram-negative bacteremia . Patient enrollment was planned to continue for 3.5 years to achieve a sample size of 276 patients . After 223 patients were randomized, 14-day mortalities were 22% in the placebo-treated group versus 21% in the steroid-treated group (p = 0.97) . In contrast, for the 51 patients with gram-negative bacteremia, mortalities were 27% placebo-treated versus 7% steroid-treated (p = 0.11) . The Data Monitoring Board recommended continuation of the trial to evaluate what appeared to be an emerging gram-negative trend, but the Cooperative Studies Evaluation Committee decided to end the trial 12 months early because of the lack of efficacy in all septic patients . The reasons for the proposed extension and for the termination of the trial are presented . The more general problem of evaluating a biologically important subgroup imbedded in a large clinical trial is also discussed. Dtsch Med Wochenschr, 1991 May 17, 116(20), 768 - 71 {A protracted course in Cardiobacterium hominis endocarditis}; Zehnter E et al.; A 69-year-old man without previous cardiac disease was found over the last 9 months to have a markedly elevated erythrocyte sedimentation rate (ESR: 120 mm/1 . h), haemolytic anaemia (haemoglobin 8.2 g/dl, lactate dehydrogenase 304 U/l), markedly reduced exercise tolerance, backache and weight loss of 5 kg . Radiological, biochemical and endoscopic examinations failed to provide a diagnosis . Nine blood cultures grew, at normal body temperature, Cardiobacterium hominis, a rare Gram-negative organism which can cause endocarditis . Echocardiography revealed endocarditis of the aortic valve with regurgitation . Despite protracted and high-dosage antibiotics (4 times daily 10 million U penicillin G for 6 days, followed by four times 5 million U penicillin G for 6 days, followed by four times 5 million U daily for five weeks, and three times daily 60 mg gentamycin for 10 days), as well as treatment of extensive chronic parodontitis, anaemia, haemolysis and increased ESR have now persisted for over a year, with negative blood cultures . Immune-complex phenomena are thought to be the reason for the persistence of signs of infection. Biochim Biophys Acta, 1991 May 2, 1089(1), 1 - 7 The alpha-ketoacid dehydrogenase complexes . Sequence similarity of rat pyruvate dehydrogenase with Escherichia coli and Azotobacter vinelandii alpha-ketoglutarate dehydrogenase; Matuda S et al.; The pyruvate dehydrogenase complex and the alpha-ketoglutarate dehydrogenase complex are multienzyme complexes consisting of three different enzymes . No significant similarity has been reported among the dehydrogenases which are component enzymes of these complexes, despite the presence of homology among the other component enzymes . Here we isolated cDNAs for the alpha and beta subunits of rat pyruvate dehydrogenase and they exhibited a significant similarity of the amino acid sequences among rat pyruvate dehydrogenase, 2-oxoisovalerate dehydrogenase (which is a dehydrogenase component of branched chain alpha-ketoacid dehydrogenase complex) and alpha-ketoglutarate dehydrogenase, suggesting that they have been derived from a common ancestral dehydrogenase . Our results suggested that the alpha and beta subunits of the pyruvate and 2-oxoisovalerate dehydrogenases have been derived by the cleavage of the alpha-ketoglutarate dehydrogenase . However, we could not find significant homology between rat pyruvate dehydrogenase and Gram-negative bacterial pyruvate dehydrogenase. Am J Pathol, 1991 May, 138(5), 1097 - 101 Intratracheal injection of endotoxin and cytokines . II . Interleukin-6 and transforming growth factor beta inhibit acute inflammation; Ulich TR et al.; The nature of the endogenous mediators that down-regulate and curtail the exodus of neutrophils into local acute inflammatory sites is unknown . In the present report, interleukin-6 (IL-6) and transforming growth factor beta (TGF beta), members of a family of macrophage-derived proteins known as cytokines, are shown to inhibit significantly the acute neutrophilic exodus caused by an intratracheal injection of endotoxin (LPS), a proinflammatory component of the cell walls of gram-negative bacteria . Transforming growth factor beta (10 micrograms) and IL-6 (10 micrograms) coinjected intratracheally with LPS (10 micrograms) each inhibited the number of neutrophils in 6-hour bronchoalveolar lavage (BAL) specimens by approximately 50% . The intratracheal coinjection of IL-6, TGF beta, and LPS inhibited the LPS-induced neutrophilic inflammatory exodus by nearly 75% . Interleukin-6 also is shown to be endogenously upregulated within the lung after intratracheal challenge with endotoxin, providing evidence that IL-6 may represent an endogenous negative feedback mechanism to inhibit endotoxin-initiated cytokine-mediated acute inflammation . Interleukin-6 and TGF beta both strongly inhibited the quantity of TNF-alpha recovered in the BAL fluid of LPS-challenged rats, suggesting that downregulation of LPS-induced TNF-alpha production within the lung represents one mechanism whereby IL-6 and TGF beta exert an antiinflammatory action . Interleukin-6 and TGF beta represent novel pharmacologic and, probably, endogenous inhibitors of acute inflammation. Arch Surg, 1991 May, 126(5), 591 - 7 Tumor necrosis factor and interleukin 1 appearance in experimental gram-negative septic shock . The effects of plasma exchange with albumin and plasma infusion; Busund R et al.; To study the effect of plasma removal vs plasma administration on the appearance of tumor necrosis factor (TNF) and interleukin 1 in septic shock, 24 anesthetized piglets were inoculated with live Escherichia coli . Plasma exchange with albumin was performed in one group . Fresh-frozen plasma was administered to a second group . A third group served as nontreated controls . Following plasma exchange, a reduction in both TNF and interleukin 1 levels occurred, whereas plasma infusion was followed by a decrease in TNF levels only . No significant differences were observed between the two treated groups with respect to survival or cardiovascular performance, with both being significantly enhanced compared with the controls . High levels of TNF and interleukin 1 correlated with depressed cardiovascular performance in the early phase of the shock . Our results confirm the important role of TNF and interleukin 1 as early mediators of septic shock . However, the benefit of reducing cytokine activity in later stages of septicemia seems to be dubious. Vopr Med Khim, 1991 May-Jun, 37(3), 26 - 8 {Functional state of the liver during development of extrahepatic cholestasis and during use of enterosorption}; Grin'ko IV et al.; Use of enterosorption during the first week of extrahepatic cholestasis in rats led to decrease of disorders in functional state of liver tissue and its subcellular organelles as well as of accumulation of toxic substances in organism . The main effect of enterosorption appears to be binding of Gram-negative bacteria endotoxin in intestine. J Vet Intern Med, 1991 May-Jun, 5(3), 167 - 81 Endotoxemia in horses . A review of cellular and humoral mediators involved in its pathogenesis; Morris DD; Endotoxemia remains the leading cause of death in horses, being intimately involved in the pathogenesis of gastrointestinal disorders that cause colic and neonatal foal septicemia . Endotoxins, normally present within the bowel, gain access to the blood across damaged intestinal mucosa, or endotoxemia occurs when gram negative organisms proliferate in tissues . Endotoxins are removed from the circulation by the mononuclear phagocyte system, and the response of mononuclear phagocytes to these lipopolysaccharides (LPS) play an important role in determining the severity of clinical disease . Macrophages become highly activated for enhanced secretory, phagocytic and cidal functions by LPS . Macrophage-derived cytokines are responsible for many of the pathophysiologic consequences of endotoxemia . The arachidonic acid metabolites, prostacyclin and thromboxane A2 likely mediate early hemodynamic dysfunction and the leukotrienes may potentiate tissue ischemia during endotoxemia . Interleukin 1 (IL-1) induces fever and is responsible for the inflammatory cascade, which constitutes the acute phase response . Tumor necrosis factor (TNF), an important proximal mediator of the effects of LPS, acts to initiate events and formation of other molecules that affect shock and tissue injury . Systemic administration of TNF produces most of the physiologic derangements that are associated with endotoxemia and antibodies that are directed against TNF significantly reduce LPS-induced mortality in experimental animals . In response to endotoxins, mononuclear phagocytes express thromboplastin-like procoagulant activity (PCA), which initiates microvascular thrombosis . Both IL-1 and TNF induce PCA expression, creating a positive feedback loop for LPS-induced coagulopathy . A macrophage-derived platelet activating factor contributes to coagulation dysfunction and further stimulates arachidonic acid metabolism . The ultimate consequences of endotoxemia are multiple system organ failure and death . The numerous feedback loops and intertwining cascades of mediators during endotoxemia defy simplistic methods of treatment . The optimal therapy likely involves methods to alter the generation of inflammatory mediators by mononuclear phagocytes. Clin Pharmacokinet, 1991 May, 20(5), 374 - 88 An updated comparison of drug dosing methods . Part III: Aminoglycoside antibiotics; Erdman SM et al.; Aminoglycoside antibiotics continue to be useful for the treatment of Gram-negative infections . Available dosing methods include predictive algorithms and nomograms, pharmacokinetics-based dosing methods, and methods that incorporate Bayesian forecasting . The individualised Sawchuk-Zaske and Bayesian methods have been extensively evaluated since the previous review in the Journal . Both methods continue to be rapid and accurate means of individualising dosage requirements for patients with diverse pharmacokinetic profiles . The predictive performance of the Bayesian method can be further enhanced when population-based parameters reflect the patient population being monitored . There are now several cost-effectiveness studies that demonstrate that pharmacokinetic dosing services for aminoglycosides result in cost savings, better therapeutic concentrations, fewer toxic serum concentrations, and shorter mean durations of hospital stay and aminoglycoside therapy . Further studies are needed for cost-effectiveness and comparison of various dosing methods in paediatric and neonatal patients. Res Vet Sci, 1991 May, 50(3), 315 - 8 Serum cortisol changes in heifers induced by lipid X: a monosaccharide precursor in the biosynthesis of Gram-negative endotoxin; Peter AT et al.; An experiment was conducted to measure the changes in serum cortisol and luteinising hormone (LH) concentrations in heifers during the luteal phase of the oestrous cycle after the administration of lipid X and Gram-negative endotoxin . Nine heifers whose oestrous cycles were synchronised with prostaglandin F2 alpha were assigned at random on day 10 after the second prostaglandin injection to one of the following groups . Group 1 heifers (n = 3) received 5 micrograms kg-1 bodyweight of Escherichia coli endotoxin as an intrauterine infusion and one hour later received an intravenous injection of lipid X (5 micrograms kg-1 bodyweight) . The treatment was reversed in group 2 heifers (n = 3), endotoxin was administered one hour after the lipid X treatment . Group 3 heifers (n = 3) received endotoxin infusion and lipid X treatment at the same time . Similar dosages and routes of administration were used in all the groups for lipid X and endotoxin treatments . Blood samples were collected once every 15 minutes for seven hours, beginning once hour before and six hours after the initial treatment . In group 1 heifers there was a fourfold increase in serum cortisol concentrations within 30 minutes after both the treatments (from 6.5 to 24.6 ng ml-1 and from 7.3 to 29.5 ng ml-1 respectively) . In group 2 heifers the cortisol concentrations increased from the baseline concentrations of 7.2 to 33.2 ng ml-1 within 30 minutes after lipid X treatment and remained at 22.5 ng ml-1 during endotoxin treatment . There was a further increase in cortisol concentrations (28.9 ng ml-1) after the endotoxin treatment.(ABSTRACT TRUNCATED AT 250 WORDS) Int J Pediatr Otorhinolaryngol, 1991 May, 21(3), 259 - 62 Branchial anomaly in a newborn presenting as stridor; Morrish TN et al.; A male patient presented at day 3 of life with a small anterior neck mass and mild intermittent upper airway obstruction . Despite intravenous antibiotics, the patient rapidly progressed to impending airway obstruction requiring surgical intervention . The clinical, radiographic, and histologic findings of this extremely rare case of a third branchial anomaly will be presented . The embryologic basis for the connection to the aerodigestive tract and the access provided to gram negative enteric organisms in newborns will be discussed. Rev Infect Dis, 1991 May-Jun, 13(3), 397 - 404 Ceftazidime plus amikacin versus ceftazidime plus vancomycin as empiric therapy in febrile neutropenic children with cancer; Viscoli C et al.; Two antibiotic regimens, ceftazidime plus amikacin and ceftazidime plus vancomycin, were compared in a prospective, randomized clinical trial as empiric therapy in febrile granulocytopenic children with cancer . The rate of response was similar in the two groups (66% vs . 77%) . The prevalence of secondary gram-negative bacteremia was higher--but not significantly higher--in the group receiving vancomycin . Adverse reactions also occurred more often in the latter group (35% vs . 4%) . Mortality did not differ significantly in the two groups . Adjustment for independent predictors of response to treatment by means of multivariate analysis confirmed the lack of any remarkable difference between the responses to the two regimens . We conclude that the use of vancomycin instead of amikacin in combination with ceftazidime does not significantly improve the outcome of treatment of fever and infection in granulocytopenic children with cancer and that the use of vancomycin is associated with an increased frequency of both secondary infections due to gram-negative bacteria and adverse reactions. JPEN J Parenter Enteral Nutr, 1991 May-Jun, 15(3), 307 - 12 Dietary manipulation of methotrexate-induced enterocolitis; Shou J et al.; Administration of chemotherapy is limited by host toxicity, which is often manifested by severe enterocolitis . This study evaluated the effects of a liquid, elemental, chemically defined diet (ED) supplemented with 2% glutamine (Glu-ED) compared with a polypeptide diet (PPD) on the morbidity and mortality after methotrexate (MTX) administration . Fischer 344 rats (n = 80) were fed either a regular rat chow diet (RD), a 2% glycine supplemented elemental diet (Gly-ED), a 2% glutamine-supplemented elemental diet (GLU-ED), and a glycine-supplemented polypeptide diet(Gly-PPD) for 7 days prior to administration of MTX (20 mg/kg, ip) . After 72 hours, eight rats per group were killed; portal vein and vena cava blood, mesenteric lymph nodes (MLN), liver, small intestine, and cecum were sampled for bacterial culture . Remaining animals were followed to calculate survival . One hundred percent of the Gly-PPD and 25% of the Glu-ED animals survived compared with 0% of the Gly-ED animals . Our data showed that ED resulted in an increased quantity of intestinal Gram-negative bacteria and diminished intestinal mucosal height and mucosal DNA/protein content . The polypeptide diet prevented intestinal mucosal atrophy, avoided MTX-induced enterocolitis and significantly improved animal survival compared with an elemental diet with or without glutamine supplementation. J Antimicrob Chemother, 1991 May, 27 Suppl C, 121 - 8 Efficacy and safety of amikacin in systemic infections when given as a single daily dose or in two divided doses . Scandinavian Amikacin Once Daily Study Group; Maller R et al.; Two hundred and twenty patients with serious infections verified or suspected to be of Gram-negative aetiology were treated in an open randomized comparative multicentre trial with amikacin 15 mg/kg/day given either as a single dose or in two divided doses at 12-h intervals . Amikacin was administered as a short-term iv infusion . When additional therapy was considered necessary piperacillin or ampicillin was recommended . The trial continues and an interim report on data from the 12 participating Scandinavian hospitals is presented . One hundred and forty-four patients have been evaluated for efficacy and 213 patients for safety . There were no significant differences between the two dosage regimens regarding efficacy and safety . A satisfactory clinical response was recorded in 129 (90%) of the evaluable patients . One serious adverse reaction was seen in a patient in the once-daily group . This was ototoxicity which was superimposed on a long standing hearing defect possibly caused by previous streptomycin therapy. Antimicrob Agents Chemother, 1991 May, 35(5), 983 - 5 Modulation of the intestinal flora of mice by treatment with aztreonam and tigemonam; van Ogtrop ML et al.; Oral and parenteral administration of aztreonam and oral administration of tigemonam to conventional mice caused a decrease in the number of aerobic gram-negative rods in the feces . Oral treatment with high doses of aztreonam (greater than or equal to 25 mg/kg/day) and tigemonam (100 mg/kg/day) adversely influenced colonization resistance, whereas oral treatment with lower doses of the monobactams or parenteral treatment with aztreonam did not. Bull Tokyo Dent Coll, 1991 May, 32(2), 63 - 70 Clinical and microbiological study of local minocycline delivery (Periocline) following scaling and root planing in recurrent periodontal pockets; Nakagawa T et al.; This study was designed to evaluate the clinical and microbiological effects of local administration of 2% minocycline-HCl ointment (Periocline) combined with scaling and root planing in recurrent periodontal pockets . Thirty-three sites were selected for this examination . The sites had probing depths greater than 5 mm and loss of attachment greater than 2 mm within the previous 3 months . They were assigned as test (22 sites) or control sites (11 sites) . After meticulous scaling (SC) and root planing (RP), Periocline was delivered into the periodontal pockets of test sites: control sites were irrigated with biological saline following SC/RP . Administration of Periocline or irrigation with saline was performed once a week for 4 consecutive weeks . The effects on clinical conditions including probing pocket depth, clinical attachment level, and bleeding on probing were evaluated at baseline, 2, 4, 8, and 12 weeks . Microbiological examinations consisting of darkfield microscopic study and culture were performed at baseline, 4, and 12 weeks . Clinical conditions improved in both groups following treatment; significantly better improvements were obtained in the test group . Microbiological study revealed that Periocline effectively eliminated periodontopathic gram-negative bacteria . These results indicated that a combination of SC/RP with local administration of 2% minocycline for recurrent periodontal pockets brought about more satisfactory results than conventional SC/RP. J Gen Microbiol, 1991 May, 137 ( Pt 5), 1215 - 22 The use of 16S ribosomal RNA analyses to investigate the phylogeny of the family Legionellaceae; Fry NK et al.; The 16S ribosomal RNA sequences of Legionella pneumophila, L . erythra, L . hackeliae, L . spiritensis, L . longbeachae, L . bozemanii (Fluoribacter bozemanae) and L . micdadei (Tatlockia micdadei) were determined using reverse transcriptase . The sequences were compared with published sequences for Gram-negative bacteria and phylogenetic trees were constructed . The data confirm previous work which showed that the family Legionellaceae forms a monophyletic subgroup within the gamma subdivision of the Proteobacteria . The data show that all of the legionellae studied are highly related (greater than 95%) on the basis of 16S rRNA sequences and do not support the division of the family Legionellaceae into three genera. J Exp Med, 1991 May 1, 173(5), 1281 - 6 Activation of the adhesive capacity of CR3 on neutrophils by endotoxin: dependence on lipopolysaccharide binding protein and CD14; Wright SD et al.; Tumor necrosis factor alpha, granulocyte colony-stimulating factor, granulocyte/macrophage colony-stimulating factor, and formyl peptide were each found to cause a twofold increase in expression of CD14 on the surface of polymorphonuclear leukocytes (PMN) . Upregulation of CD14 was complete by 20 min and thus appeared to result from expression of preformed stores of protein . The CD14 on the surface of PMN was shown to serve two biological functions . It bound particles coated with complexes of lipopolysaccharide (LPS) and LPS binding protein (LBP) . This binding activity was enhanced by agonists that upregulated CD14 expression and may serve in the clearance of Gram-negative bacteria opsonized with LBP . Interaction of CD14 with LPS in the presence of LBP or serum also caused a dramatic, transient increase in the adhesive activity of CR3 (CD11b/CD18) on PMN . Enhanced activity of CR3 and other members of the CD11/CD18 family underlies many of the known physiological responses of PMN to LPS and may be a central feature of the in vivo responses of PMN to endotoxin. Carbohydr Res, 1991 Apr 2, 211(1), 91 - 102 L-guluronan-specific alginate lyase from a marine bacterium associated with Sargassum; Brown BJ et al.; The major extracellular alginate lyase activities secreted by a Gram-negative, facultative bacterium associated with actively growing Sargassum fluitans have been resolved an examined for substrate specificity . A fraction excluded from Sephadex G-75 was equally active toward (1----4)-beta-D-mannuronan, (1----4)-alpha-L-guluronan, and alginate with the formation of di- and tri-saccharides as apparent limit products and oligo-saccharides indicative of an endolytic mechanism . A second fraction which was included during G-75 filtration was inactive toward D-mannuronan and 4 times more active toward L-guluronan than native alginate . Proton magnetic resonance spectrometry identified the primary product of this enzyme as O-(4-deoxy-alpha-L-erythro-hex-4-enopyranosyluronic acid)-(1----4)-O-(alpha-L-gulopyranosyluronic acid)-(1----4)-O-alpha-L-gulopyranuronic acid . The L-guluronan-specific enzyme requires 0.5 M NaCl for maximal activity and has been purified as a monomeric protein having an apparent molecular mass of 38 kD and an approximate pI of 4.5 . The predominant formation of trisaccharide over the course of a reaction showed a primarily exolytic mechanism, indicating an enzyme activity unique from any previously reported. Arch Mal Coeur Vaiss, 1991 Apr, 84(4), 569 - 72 {Colonic angiodysplasia with chronic digestive hemorrhage cured after valvular replacement for aortic valve stenosis}; Obadia JF et al.; Aortic stenosis is found in 15 to 25% of patients with gastrointestinal angiodysplasia . The usual treatment for haemorrhagic angiodysplasia associated with aortic stenosis is the same as for other types of gastrointestinal angiodysplasias: segmental intestinal resection, electrocoagulation and laser photocoagulation . The authors report the case of a 73 year old woman with a long history of gastro-intestinal bleeding and chronic anaemia requiring a number of hospital admissions for blood transfusions . The cause of this bleeding remained obscure for many years, as it was initially thought to be due to portal hypertension complicating cyrrhosis and a surgical porto-caval shunt was performed . Later, angiodysplasia of the colon was recognised and a segmental colonic resection was performed . These two surgical procedures had no effect on the chronic bleeding and finally the patient was referred for a gram negative endocarditis complicating aortic stenosis, previously considered to be non-surgical . After controlling the infection, the patient was sent for surgery of the aortic valve disease with mitral regurgitation in view of progressive degradation of left ventricular function . A double valve replacement with bioprostheses was undertaken with no complication . Finally, three years now after valve replacement, no further bleeding has occurred and control colonoscopy is normal . In the light of this case and a review of the literature of about 30 similar cases, the physiopathology and management of these patients is discussed with respect to the choice of valve prosthesis and the attitude to anticoagulant therapy . These observations suggest that in the presence of valvular heart disease at a surgical stage associated to an angiodysplasia, it is preferable to propose valve surgery to start with . Gastro-intestinal surgery is only indicated if haemorrhage persists after a period of observation. Kidney Int, 1991 Apr, 39(4), 618 - 23 Role of neutrophil derived oxidants and elastase in lipopolysaccharide-mediated renal injury; Linas SL et al.; Gram-negative bacterial sepsis is frequently associated with acute renal failure but the specific effects of lipopolysaccharide (LPS) and other bacterial products on kidney function are not known . Since either LPS or formyl-methionyl-leucyl-phenylalanine (FMLP)--a chemotactic peptide from bacterial cell walls--activate neutrophils (PMN) to release a number of potentially toxic factors in vitro, we determined the effect of adding PMN with LPS and/or FMLP to isolated perfused rat kidneys . Isolated rat kidneys perfused with LPS alone or LPS and normal PMN had normal glomerular filtration rates (GFR) and tubular Na reabsorption (TNa) . Kidneys perfused with FMLP alone or FMLP and normal PMN also had normal GFR and TNa . In contrast, addition of PMN with both FMLP and LPS caused progressive renal dysfunction . For example, after 60 minutes of perfusion, GFR was reduced from 610 +/- 31 to 147 +/- 17 microliters/min/g and TNa from 97 +/- 1 to 72 +/- 2%, both P less than 0.01 . Perfusion with the O2 metabolite scavengers catalase or dimethylthiourea afforded no protection while perfusion with the neutrophil elastase inhibitor Eglin C conferred substantial, but not complete, protection: GFR 492 +/- 34 microliters/min/g; TNa 91 +/- 3% . However, perfusion with both Eglin C and catalase completely prevented the toxic effects of LPS and FMLP-treated PMN on renal function . We conclude that in isolated kidneys, 1) the toxic effects of LPS requires FMLP-treated PMN and that 2) LPS and FMLP treated PMN cause progressive renal injury which is mediated by both O2 metabolites and neutrophil elastase. Masui, 1991 Apr, 40(4), 605 - 10 {Evaluation of the dose of endotoxin to produce endotoxin shock models in dogs}; Yoshizawa M et al.; Intravenous bolus administration of purified endotoxin (ET) is one of the most popular methods of producing experimental ET shock . In an attempt to evaluate the dose of ET in these experimental models, the kinetics of ET was assessed in various doses (1-0.002 mg.kg-1), and dose response study was performed, measuring chronological changes in hemodynamic (mean arterial pressure & cardiac output) and hematological (leucocyte & platelet counts) parameters . It was demonstrated that plasma ET concentrations were sustained extraordinarily high (greater than 5000 pg.ml-1) in doses of 0.2-1 mg.kg-1 during the observation period of several hours, while they were measurable in doses of 0.02 and 0.002 mg.kg-1, showing a biphasic decrease pattern after ET administration . In particular, plasma ET levels of low dose group (0.002 mg.kg-1) were similar to those of clinical gram negative septic patients . We conclude that the empirically used ET doses of more than 1 mg.kg-1 produce extremely severe endotoxemia and that milder degree of ET shock models produced by low dose of ET (0.002 mg.kg-1) would be more applicable for a pathophysiological study of ET shock. Gut, 1991 Apr, 32(4), 450 - 1 Septicaemia after colonoscopy in patients with cirrhosis; Thornton JR et al.; Two patients with ulcerative colitis and chronic active hepatitis with cirrhosis, who developed Gram negative septicaemia after colonoscopy are described . These and two similar reported cases indicate that giving prophylactic antibiotics to patients with cirrhosis undergoing colonoscopy should be considered, particularly when the cirrhosis is advanced. J Exp Med, 1991 Apr 1, 173(4), 1021 - 4 Detection of interleukin 8 and tumor necrosis factor in normal humans after intravenous endotoxin: the effect of antiinflammatory agents; Martich GD et al.; Interleukin 8 (IL-8), a potent activator of neutrophils, may be important in the early host response to serious Gram-negative infections . IL-8 was measured with other acute phase cytokines (tumor necrosis factor alpha {TNF-alpha}, IL-6 and IL-1 beta) in 25 normal humans randomized to receive either intravenous endotoxin alone or endotoxin after oral administration of ibuprofen or pentoxifylline, agents that alter some of the inflammatory responses induced by endotoxin in vitro . TNF immunoreactivity was maximum at 1.5 h, and total TNF (area under the curve) was 4.2- and 4.5-fold greater in subjects given endotoxin/ibuprofen compared to subjects given endotoxin alone (p = 0.026) or endotoxin/pentoxifylline (p = 0.004), respectively . IL-6 levels were maximum at 2-3 h and did not differ among the three groups . No IL-1 beta was detected in any subject . IL-8 levels peaked at 2 h in subjects given either endotoxin alone or endotoxin/pentoxifylline, falling towards baseline by 5 h . Subjects given endotoxin/ibuprofen had a more sustained rise in IL-8 with peak levels 2.8- and 2.5-fold higher at 3 h compared to endotoxin alone (p = 0.048) or endotoxin/pentoxifylline (p = 0.023), respectively . Differences in total IL-8 release among groups approached statistical significance (ANOVA, p = 0.07) . This trend reflected the increased release of IL-8 by the subjects receiving ibuprofen compared to pentoxifylline (1.9-fold higher; p = 0.024) . This suggests that cyclooxygenase products may provide important negative feedback loops for cytokine production in vivo . Increases in circulating IL-8 are part of the acute inflammatory response of humans to endotoxin . Altered cytokine responses caused by antiinflammatory therapy may have important implications for both host defense and injury during septicemia. Infect Immun, 1991 Apr, 59(4), 1394 - 401 Regulation of leukotoxin in leukotoxic and nonleukotoxic strains of Actinobacillus actinomycetemcomitans; Spitznagel J Jr et al.; Actinobacillus actinomycetemcomitans is a gram-negative bacterium that has been implicated in the etiology of several forms of periodontitis, especially localized juvenile periodontitis . A potent leukotoxin (Lkt) is produced by most A . actinomycetemcomitans isolates from patients with periodontal disease, but some isolates are leukotoxin nonproducing (Lkt-) . The molecular bases for the differences in leukotoxin expression are being explored to clarify the role of leukotoxin in pathogenesis . We have previously cloned the leukotoxin structural gene, lktA, from the leukotoxin-producing (Lkt+) strain JP2 and have shown that it is linked to three other genes, lktB, lktC, and lktD, whose gene products are thought to be required for activation and localization of the leukotoxin . These genes have now been used in Southern blot analysis to demonstrate that Lkt- strains, like Lkt+ strains, contain all four genes of the lkt gene cluster . While restriction fragment length polymorphisms were detected, they did not correlate with toxin phenotype . RNA blot analysis demonstrated that Lkt+ strains produced two transcripts, one 9.3 kb in length and the other 4.3 kb . They encode lktCABD and lktCA . respectively . Lkt- strains contained significantly lower levels of the 4.3-kb transcript with no discernible 9.3-kb message . The leukotoxic activity of the A . actinomycetemcomitans strains, measured by chromium release assays, correlated with the lkt RNA content . Therefore, a major component of leukotoxin regulation is at the level of RNA transcription or stability . Interestingly, the lkt RNAs in JP2 are regulated during growth phase, being greatly reduced in cells approaching stationary phase . Thus, the regulation of lkt RNA can be affected by both genotype and environment. DICP, 1991 Apr, 25(4), 357 - 9 In vivo inactivation of tobramycin by piperacillin; Uber WE et al.; In vivo inactivation of aminoglycosides by antipseudomonal penicillins in patients with renal failure can be a significant problem when these drugs are used together in certain gram-negative infections . Our article illustrates the possible magnitude of this interaction and the resultant effect on aminoglycoside pharmacokinetic parameters . Penicillin concentrations remain relatively unaffected by this interaction . This article stresses the need for close monitoring of aminoglycoside concentrations when combined with antipseudomonal penicillins in this patient population. J Chemother, 1991 Apr, 3(2), 98 - 100 Aztreonam biliary excretion in bile duct ligated jaundiced rats; Rulli F et al.; An experimental study was undertaken to assess aztreonam biliary concentrations in bile duct ligated jaundiced rats . The study proved that aztreonam biliary concentrations are sufficient to inhibit Gram-negative bacteria within the first and the second hour after antibiotic administration . The experimental model suggests that clinical conditions such as lithiasis or neoplasms of the biliary tree should not totally inhibit the antibiotic excretion. J Gen Microbiol, 1991 Apr, 137 ( Pt 4), 905 - 11 Characterization and comparative bactericidal activity of monoclonal antibodies to Bordetella pertussis lipo-oligosaccharide A; Archambault D et al.; Spleen cells from mice immunized with a Bordetella pertussis N-lauroyl sarcosine membrane extract (SME) were used to generate hybridoma cells lines producing monoclonal antibodies (mAbs) . Seven mAbs were shown to be specific to B . pertussis lipo-oligosaccharide (LOS) by immunoblotting of SME or purified LOS following SDS-PAGE . All mAbs reacted with the B . pertussis Tohama I strain of the LOS AB phenotype, and did not react with the atypical variant strain 134 of the LOS B phenotype . The immune reactivity of the mAbs was retained after treatment of SME with proteinase K and was lost after sodium periodate treatment . No cross-reactivity was observed with the mAbs when tested against B . parapertussis and other Gram-negative bacteria . However, all mAbs reacted with B . bronchiseptica . Binding assays with live B . pertussis cells demonstrated that mAbs strongly reacted with cell surface exposed antigenic determinants . High bacterial cell lytic capability was observed for five of these mAbs . Concentrations between 0.22 and 2.2 micrograms mAb ml-1 (0.1 and 1 microgram per 450 microliter assay) purified by protein A were required to kill at least 50% of the bacteria . Competition immunoassays with biotinylated antibodies showed that the bacteriolytic and non-bacteriolytic mAbs were directed to different epitopes of the B . pertussis LOS A. Can J Surg, 1991 Apr, 34(2), 137 - 43 Acute pancreatitis--30 years' experience at a teaching hospital; Amurawaiye EO et al.; Advances in medical technology and knowledge have influenced morbidity and mortality in surgically treated diseases . The authors have compiled four consecutive retrospective studies of demography, morbidity and mortality of patients with acute pancreatitis to summarize the experience from 1956 to 1985 at the Montreal General Hospital with 629 patients . The death rate has remained unchanged . Hypotension, gastrointestinal bleeding and respiratory failure have assumed lesser roles as major complicating factors . Renal failure and gram-negative aerobic pancreatic sepsis are the common causes of death . The last two reviews revealed that surgical debridement and drainage combined with appropriate biliary procedures salvaged two-thirds of the patients with sepsis . Deteriorating nutritional status, heralded by a fall of serum albumin level below 30 g/L, is associated with a poor prognosis . Interval cholecystectomy in patients with mild biliary tract pancreatitis is associated with a low death rate (0.01%). J Infect Dis, 1991 Apr, 163(4), 762 - 8 Antibodies to core lipopolysaccharide determinants: absence of cross-reactivity with heterologous lipopolysaccharides; Heumann D et al.; Using monoclonal antibodies directed against defined epitopes of endotoxin core, this study demonstrated that the presentation of lipopolysaccharide (LPS) to antibodies is critical for measuring the specific binding of antibodies to LPS structures . False cross-reactive reactions apparently were observed when free core LPS or lipid A were used as antigens in ELISA, whereas coating with complexes of high-density lipoproteins with core LPS increased both the sensitivity and the specificity of the test compared with coating with free core LPS, so that nonspecific binding of antibodies was largely avoided . Using this technique, it was not possible to find broadly cross-reactive core LPS antibodies after immunization of rabbits and humans with rough mutants of gram-negative bacteria . These observations underscore the need for careful evaluation of the potential for cross-reactivity of antisera and of monoclonal antibodies directed against endotoxin core. Lab Anim Sci, 1991 Apr, 41(2), 146 - 50 Infusion-related sepsis in dogs undergoing acute cardiopulmonary surgery; Slattum MM et al.; During acute cardiopulmonary studies, 33 of 170 (19.4%) dogs developed uncontrollable acidosis accompanied by varying degrees of diarrhea and hypotension . Affected dogs had evidence of gram-negative bacteremia and septic shock . Intravenously administered fluids were contaminated with gram-negative bacteria . Since the experimental procedure entailed nonsurvival surgery, aseptic techniques were not employed . Although aseptic surgical techniques are to be used in animals undergoing survival surgery, such techniques also may be warranted in non-survival surgeries. Resuscitation, 1991 Apr, 21(2-3), 137 - 80 The cell in shock: the origin of multiple organ failure; Schlag G et al.; The immediate organ damage seen after multiple trauma and in shock is a typical example of non-bacterial inflammation triggered by activation of various mediators of both the humoral and cellular systems . Anaphylatoxins and the low-flow syndrome during the shock phase account for increased PMN* margination, which in turn causes pulmonary leukostasis and may provoke massive mediator release by PMN (oxygen radicals, proteinases, eicosanoids, PAF etc) . This probably leads to severe endothelial cell damage, especially in the lung . Adherence of PMN to the endothelium appears to create the micro-environment where high concentrations of proteolytic enzymes and reactive oxygen radicals exert a deleterious effect on the cell membrane . Endothelial cell membrane injury leads to increased vascular permeability and cell edema . The development of the 'organ in shock' may require a few hours and initially cause minor or no functional impairment at all . Only when shock is severe is there early organ failure, which in this stage may still be an expression of non-bacterial inflammation . Numerous studies have reported the existence of shock-induced cardiodepressant substances in association with various forms of circulatory shock . We have determined a net negative inotropic effect of the low-molecular-weight plasma fraction in severe hypovolemic-traumatic shock and have isolated a cardiodepressant factor (CDF), which by blockade of the calcium inward current has a negative inotropic a chronotropic effect . The intestine as a shock organ appears to range first among the organs involved . The translocation of bacteria from the intestinal tract, the 'intestine in shock' represents the trigger reaction that eventually leads from the 'organ in shock', early organ failure to late (septic) organ failure . Here the most prominent factor is endotoxin (LPS) as a basic mediator of gram-negative bacteria, which also triggers the activation of humoral and cellular systems . The posttraumatic hyperdynamic phase commonly starts on days 3-5 and is mainly caused by bacteremia and/or endotoxemia . Macrophages have a major impact on the late phase of organ failure . At present, the most prominent cellular mediator of the lethal effect of endotoxin is thought to be cachectin, which is identical with the tumor necrotising factor (TNF) . TNF is secreted by monocytes/macrophages (MO/MA) in response to LPS . Via macrophage derived cytokines and by LPS there is activation of endothelial cells, with increased adhesiveness for PMN . Both due to this increased adhesiveness and the presence of LPS and cytokines, PMN undergo massive activation, which causes mediator release and tissue damage.(ABSTRACT TRUNCATED AT 400 WORDS) Nature, 1991 Mar 14, 350(6314), 167 - 70 Structural architecture of an outer membrane channel as determined by electron crystallography; Jap BK et al.; Porins are a family of membrane channels commonly found in the outer membranes of Gram-negative bacteria where they serve as diffusional pathways for waste products, nutrients and antibiotics, and can also be receptors for bacteriophages . Porin channels have been shown in vitro to be voltage-gated . They can exhibit slight selectivities for certain solutes; for example PhoE porin has some selectivity for anionic and phosphate-containing compounds . Unlike many known membrane proteins which often contain long stretches of hydrophobic segments that are believed to traverse the membrane in a helical conformation, porins are found to have charged residues distributed almost uniformly along their primary sequences and have most of their secondary structure in a beta-sheet conformation . We have made crystalline patches of PhoE porin embedded in a lipid bilayer and have used these to determine the structure of PhoE porin by electron crystallography to a resolution of 6A . The basic structure consists of a trimer of elliptically shaped, cylindrical walls of beta sheet . Each cylinder has an inner lining, formed by parts of the polypeptide, that defines the channel size . The structure provides a clue as to how deletions of segments of polypeptide, which are found in certain mutants, can result in an actual increase in the channel size. Bone Marrow Transplant, 1991 Mar, 7(3), 227 - 34 Prevention of cytomegalovirus infection following bone marrow transplantation: a randomized trial of blood product screening; Miller WJ et al.; From 1983 to 1987, cytomegalovirus seronegative allogeneic bone marrow recipients were randomized to receive screened cytomegalovirus (CMV) seronegative or unscreened blood products and 125 patients were available for analysis . CMV infection occurred in 18% of patients in the screened versus 38% in the unscreened blood product group . However, only two of 64 patients in the screened group and seven of 61 in the unscreened group developed culture or biopsy-proven CMV infections . Bone marrow donor CMV seropositivity was associated with an increased risk of developing CMV infection (21% with seronegative and 46% with seropositive donor), and CMV infection was not prevented by blood product screening if the bone marrow donor was sero = positive (62% for screened, 42% for unscreened group, p = 0.80) . One year survival censored for relapse was 52% in the screened group versus 68% in the unscreened group (p = 0.08) . Gram negative bacteremia complicated bone marrow transplantation (BMT) in 35% of patients receiving screened and 15% of those receiving unscreened blood products (p = 0.02) . Relapse did not differ in the screened and unscreened groups . By multivariate analysis, high risk disease (p = 0.0002), CMV infection (p = 0.004), screened blood products group (p = 0.011), recipient age greater than 17 (p = 0.027), chronic graft-versus-host disease (p = 0.014) and gram negative bacteremia (p = 0.004) independently had a negative influence on survival . We conclude that blood product screening was effective in preventing CMV infections following BMT if both the recipient and bone marrow donor were CMV seronegative.(ABSTRACT TRUNCATED AT 250 WORDS) J Mol Biol, 1991 Mar 5, 218(1), 141 - 8 Carboxy-terminal phenylalanine is essential for the correct assembly of a bacterial outer membrane protein; Struyve M et al.; Bacterial outer membrane proteins are supposed to span the membrane repeatedly, mostly in the form of amphipathic beta-sheets . The last ten C-terminal amino acid residues of PhoE protein are supposed to form such a membrane-spanning segment . Deletion of this segment completely prevents incorporation into the outer membrane . Comparison of the last ten amino acid residues of other outer membrane proteins from different Gram-negative bacteria revealed the presence of a potential amphipathic beta-sheet with hydrophobic residues at positions 1 (Phe), 3 (preferentially Tyr), 5, 7 and 9 from the C terminus, in the vast majority of these proteins . Since such sequences were not detected at the C termini of periplasmic proteins, it appears to be possible to discriminate between the majority of outer membrane proteins and periplasmic proteins on the basis of sequence data . The highly conserved phenylalanine at the C termini of outer membrane proteins suggests an important function for this amino acid in assembly into the outer membrane . Site-directed mutagenesis was applied to study the role of the C-terminal Phe in PhoE protein assembly . All mutant proteins were correctly incorporated into the outer membrane to some extent, but the efficiency of the process was severely affected . It appears that both the hydrophobicity and the aromatic nature of Phe are of importance. Circ Shock, 1991 Mar, 33(3), 127 - 34 Lethal E . coli septic shock is prevented by blocking tissue factor with monoclonal antibody; Taylor FB Jr et al.; Gram-negative bacteremia poses a major health problem, causing one-half of cases of lethal septic shock acquired during hospitalization . Bacterial lipopolysaccharide (LPS) and the inflammatory cytokines, tumor necrosis factor (TNF) and interleukin-1 (IL-1), have been shown to be essential mediators of septic shock . Among the effects of these mediators is a coagulopathy that may be triggered by induced expression of tissue factor (TF) on macrophages and endothelial cells . We now report that 500 micrograms/kg of either immunoglobulin G (IgG) or Fab fragments of a monoclonal antibody against TF administered to baboons as a pretreatment attenuates the coagulopathy and protects against LD100 Escherichia coli . This study provides direct evidence of an essential effector role for TF in septic shock. Rev Infect Dis, 1991 Mar-Apr, 13(2), 201 - 6 Leptotrichia buccalis bacteremia in patients with cancer: report of four cases and review; Weinberger M et al.; Leptotrichia buccalis, an anaerobic gram-negative rod, is part of the normal oral flora and has rarely been isolated from clinical material . We describe four patients with neutropenia and progressive malignancy who had symptomatic L . buccalis bacteremia, and we review an additional four cases from the literature . The mean age of the patients was 31 years (range, 7-73 years), with an equal number of males and females . The number of positive blood cultures in each case ranged from one to four (mean, two); these cultures became positive after 48-120 hours (median, 54 hours) . All tested isolates were sensitive to the beta-lactam agents, clindamycin, tetracycline, and metronidazole; five of seven were sensitive to chloramphenicol; and not one was sensitive to the aminoglycosides, vancomycin, ciprofloxacin, or erythromycin . Seven patients had one or more possible portals of entry for bacteremia, including mucositis (four patients), mucositis plus esophageal lesions (two), and possible mucositis plus diverticulitis (one) . L . buccalis should be considered a potential pathogen in neutropenic patients, especially when breaks in the mucosal breaks in the mucosal barriers are present. J Invertebr Pathol, 1991 Mar, 57(2), 166 - 71 Rickettsiae in gill epithelial cells of the hard clam, Mercenaria mercenaria; Fries CR et al.; Rickettsiae are found in the gill epithelium of the hard clam, Mercenaria mercenaria . The procaryotes occur free in the cytoplasm of the epithelial cells at the tip of the filament and in the more proximal cells that support the lateral J cilia . The fine structure of the organisms, showing rippled cell walls, is typical of the rickettsiae . The increasing size of the inclusion representing late phase growth often culminates in lysis of the host cell . Masses (Gram-negative, Feulgen-positive) in ova, similar to those observed in the gill epithelium, suggest that transovarian transmission may occur. Arch Intern Med, 1991 Mar, 151(3), 603 - 4 Flavimonas oryzihabitans (Pseudomonas oryzihabitans; CDC group Ve-2) bacteremia in the immunocompromised host; Decker CF et al.; Flavimonas oryzihabitans, known previously as Pseudomonas oryzihabitans, and a member of the Centers for Disease Control group Ve-2, is a gram-negative organism that has rarely been implicated as a human pathogen . Flavimonas oryzihabitans appears to be a soil and saprophytic organism that survives in moist environments and is indigenous to rice paddles . To our knowledge, only seven cases of human infection caused by this organism have been reported; they involved four patients with bacteremia and three patients with peritonitis who were receiving continuous ambulatory peritoneal dialysis . In this report, we describe three immunocompromised patients with catheter-associated bacteremia: a patient with cancer, a patient with acquired immunodeficiency syndrome, and a patient with sickle cell disease . There is emerging clinical evidence that F oryzihabitans should be recognized as an organism that is capable of causing human disease, particularly in immunocompromised patients and with the increased usage of permanent catheters. Am J Physiol, 1991 Mar, 260(3 Pt 2), H832 - 41 Coronary vascular smooth muscle function in E . coli endotoxemia in dogs; Parker JL et al.; The purpose of this study was to determine whether intrinsic contraction-relaxation properties of coronary arteries are altered during acute gram-negative endotoxemia . Coronary vascular smooth muscle (VSM) was evaluated in vitro using large and small left circumflex coronary ring preparations isolated from dogs 4 h after administration of either saline (control; C) or 1.5 mg/kg Escherichia coli endotoxin (ET) . ET dogs exhibited marked systemic hypotension and cardiovascular depression throughout the 4-h in vivo phase of the study accompanied by reduction in total left ventricular myocardial blood flow . Isolated coronary vessels were stretched to the apex of the length-contractile tension curve; no differences were observed in length-active or length-passive tension (vessel compliance) relationships between C and ET vessels . Isometric contractions produced by K+ and prostaglandin F2 alpha (PGF2 alpha) were similar in C and ET coronary arteries . VSM relaxant responses to nitroprusside (NP; 10(-10) to 10(-4) M) were also similar in C and ET vessels . In contrast to the apparent lack of effect of ET on directly acting VSM agents, relaxation responses to the endothelial-dependent vasodilator acetylcholine (ACh) were significantly less in ET vessels . Impaired vasodilator response to ACh was not improved by in vivo treatment with the combination antioxidant therapy of allopurinol, superoxide dismutase, and catalase . We conclude that both depolarization (K+) and receptor (PGF2 alpha)-mediated contractile mechanisms, as well as basal cGMP (NP)-mediated vasodilator mechanisms, remained functional in coronary vasculature during acute endotoxemia . Inhibition of ACh-mediated relaxation in ET vessels suggests altered endothelial-dependent vasodilation in coronary arteries during endotoxemia, but this change did not seem to be associated causally with oxygen free radicals. Infect Immun, 1991 Mar, 59(3), 1131 - 40 Changes in the surface of Leptospira interrogans serovar grippotyphosa during in vitro cultivation; Haake DA et al.; Surface components of virulent and attenuated Leptospira interrogans serovar grippotyphosa were compared by using Triton X-114 solubilization and phase partitioning, immunoprecipitation of intact organisms, and freeze-fracture electron microscopy . Removal of the leptospiral outer membrane by using 0.1% Triton X-114 was demonstrated by whole-mount electron microscopy and by essentially complete solubilization of a lipopolysaccharidelike substance (LLS) from the outer membrane . Triton X-114 (0.1%) did not solubilize subsurface proteins, such as endoflagellar filaments or penicillin-binding proteins, which are markers for the periplasmic space and inner membrane, respectively . Triton X-114 solubilized material from both the virulent and attenuated strains, which partitioned into the hydrophobic, detergent phase, contained LLS and major proteins of 41 and 44 kDa, which were also immunoprecipitable from intact organisms . The virulent strain contained greater amounts of an LLS component with an apparent molecular mass of 30 kDa (R(f) = 0.57), whereas the attenuated strain contained larger amounts of an LLS component with an apparent molecular mass of 20 kDa (R(f) = 0.74) . Differences in protein components between virulent and attenuated organisms were also detected; whereas the 41- and 44-kDa proteins were immunoprecipitated in equal amounts from both the virulent and attenuated strains, a 33-kDa protein was immunoprecipitated in significantly greater amounts from the attenuated strain . Quantitation of outer membrane particle density by freeze-fracture electron microscopy showed that both strains had a low transmembrane outer membrane protein content compared with that of typical gram-negative bacteria . The virulent and attenuated strains had 443 and 990 particles (P less than 0.000001) per micron, respectively, in the concave outer membrane fracture face . These findings suggest that in vitro cultivation of L . interrogans is accompanied by quantitative and qualitative changes in both LLS and outer membrane-associated proteins. Clin Orthop, 1991 Mar, (264), 178 - 83 Analysis of 61 cases of vertebral osteomyelitis; Patzakis MJ et al.; Sixty-one cases of bacterial vertebral osteomyelitis from July 1969 to July 1979 were analyzed . The ages of the 49 men and 12 women ranged from 21 to 66 years . The portal of