J Bacteriol, 1995 May, 177(10), 2827 - 33 Molecular characterization of the staphylococcal multidrug resistance export protein QacC; Paulsen IT et al.; The QacC polypeptide is a member of a family of small membrane proteins which confer resistance to toxic compounds . The staphylococcal qacC gene confers resistance to toxic organic cations via proton-dependent export . The membrane topology of the QacC polypeptide was investigated by constructing and analyzing a series of qacC-phoA and qacC-lacZ fusions . From these analyses, most of the predicted features of the QacC protein were verified, although data regarding the possible orientation of the COOH region were not conclusive . The role of the sole cysteine residue, Cys-42, in QacC was studied by using the sulfhydryl reagent N-ethylmaleimide and site-directed mutagenesis . N-Ethylmaleimide was shown to inhibit qacC-mediated ethidium export . Multiple amino acid substitutions were made for Cys-42, and mutations at this location had various effects on resistance specificity . This suggests that the Cys-42 residue may be located near a region of QacC that is involved in substrate recognition . Mutagenesis of conserved residues in QacC indicated that Tyr-59 and Trp-62 also play an essential structural or functional role in QacC. Arch Dermatol, 1995 May, 131(5), 552 - 5 Cultures of skin biopsy tissue from immunocompromised patients with cancer and rashes; Chren MM et al.; BACKGROUND AND DESIGN: Microbiological cultures of skin biopsy tissue are often recommended in immunocompromised patients with cancer and rashes, but in a previous study, they were usually sterile or grew clinically insignificant organisms . To examine the use and bacteriological results of these cultures more comprehensively, we reviewed records from all immunocompromised adults with cancer and acute rash on which skin biopsy was performed during 39 months on a bone marrow transplantation/acute leukemia unit of a university hospital (108 episodes of rash in 80 patients) . RESULTS: Of the 158 cultures that were performed, one (1%; 95% confidence interval {CI}, 0% to 4%) was a true positive; 11 (7%; 95% CI, 3% to 13%) were false positive; 143 (91%; 95% CI, 87% to 95%) were true negative; and three (2%; 95% CI, 1% to 6%) were false negative . Thus, the sensitivity of culture was 0.25, and the specificity was 0.93 . Coagulase-negative Staphylococcus was the single pathogenic organism that grew, yet was judged to be a contaminant in three episodes . Among the 95 rashes in which fewer than four types of culture were performed, viral culture may have been helpful in one case (1%; 95% CI, 0% to 6%) . CONCLUSIONS: Cultures of skin tissue from immunocompromised cancer patients with rashes were often unable to diagnose infection or the absence of infection . Clinical judgement was crucial to the interpretation of culture results. J Bacteriol, 1995 May, 177(9), 2408 - 15 Characterization of a genetic locus essential for maltose-maltotriose utilization in Staphylococcus xylosus; Egeter O et al.; A genetic locus from Staphylococcus xylosus involved in maltose-maltotriose utilization has been characterized . The chromosomal region was identified by screening a genomic library of S . xylosus in Escherichia coli for sucrose hydrolase activity . Nucleotide sequence analysis yielded two open reading frames (malR and malA) encoding proteins of 37.7 and 62.5 kDa, respectively . MalR was found to be homologous to the LacI-GalR family of transcriptional regulators, and MalA showed high similarity to yeast alpha-1,4-glucosidases and bacterial alpha-1,6-glucosidases . Inactivation of malA in the genome of S . xylosus led to a maltose-maltotriose-negative phenotype . In cell extracts of the mutant, virtually no glucose release from maltose and short maltodextrins was detectable . Inactivation of malA in a sucrose-6-phosphate hydrolase-deficient S . xylosus strain resulted in the complete loss of the residual sucrose hydrolase activity . The MalA enzyme has a clear preference for maltose but is also able to release glucose from short maltosaccharides . It cannot cleave isomaltose . Therefore, malA encodes an alpha-1,4-glucosidase or maltase, which also liberates glucose from sucrose . Subcloning experiments indicated that malA does not possess its own promoter and is cotranscribed with malR . Its expression could not be stimulated when maltose was added to the growth medium . Chromosomal inactivation of malR led to reduced maltose utilization, although alpha-glucosidase activity in the malR mutant was slightly higher than in the wild type . In the mutant strain, maltose uptake was reduced and inducibility of the transport activity was partially lost . It seems that MalR participates in the regulation of the gene(s) for maltose transport and is needed for their full expression . Thus, the malRA genes constitute an essential genetic locus for maltosaccharide utilization in S . xylosus J Immunol, 1995 May 1, 154(9), 4883 - 94 Increased frequency of gamma delta T cells in cerebrospinal fluid and peripheral blood of patients with multiple sclerosis . Reactivity, cytotoxicity, and T cell receptor V gene rearrangements; Stinissen P et al.; Infiltrating gamma delta T cells are potentially involved in the central nervous system demyelination in multiple sclerosis (MS) . To further study this hypothesis, we analyzed the frequency and functional properties of gamma delta T cells in peripheral blood (PB) and paired cerebrospinal fluid (CSF) of patients with MS and control subjects, including patients with other neurologic diseases (OND) and healthy individuals . The frequency analysis was performed under limiting dilution condition using rIL-2 and PHA . After PHA stimulation, a significantly increased frequency of gamma delta T cells was observed in PB (14.7 x 10(-4)) and in CSF (15.8 x 10(-4)) of MS patients as compared with 4.3 x 10(-4) in PB and 3.9 x 10(-4) detected in CSF of patients with OND . The frequency was represented equally in OND patients and normal individuals . Similarly, the IL-2-responsive gamma delta T cells occurred at a higher frequency in PB of control subjects (1.1 x 10(-4)) in OND patients and 1.5 x 10(-4) in normal individuals) . Forty-three percent (13 of 30) of the gamma delta T cell clones isolated from PB and CSF of MS patients responded to heat shock protein (HSP70) but not HSP65, whereas only 2 of 30 control gamma delta T cell clones reacted to the HSP . The majority of the gamma delta T cell clones were able to induce non-MHC-restricted cytolysis of Daudi cells . All clones displayed a substantial reactivity to bacterial superantigens staphylococcal enterotoxin B and toxic shock syndrome toxin-1, irrespective of their gamma delta V gene usage . Furthermore, the gamma delta T cell clones expressed predominantly TCRDV2 and GV2 genes (26 of 35 clones), whereas the clones derived from CSF of MS patients expressed either DV1 or DV2 genes . The obtained gamma delta clones, in general, represented rather heterogeneous clonal origins, even though a predominant clonal origin was found in a set of 10 gamma delta clones derived from one patient with MS . The present study provides new evidence supporting a possible role of gamma delta T cells in the secondary inflammatory processes in MS. J Immunol, 1995 May 1, 154(9), 4247 - 60 T cell receptor V alpha 4 is expressed by a subpopulation of V beta 6 T cells that respond to the bacterial superantigen staphylococcal enterotoxin B; Borrero H et al.; A subpopulation of murine minor lymphocyte-stimulating locus Ag (Mls)-1a-responsive, TCR V beta 6-expressing T hybrids was responsive to the superantigenic bacterial toxin, staphylococcal enterotoxin B (SEB), presented by murine MHC class II molecules . Comparative functional and surface marker analyses showed that this heterogeneity was not caused by nonspecific effects . It seemed, therefore, that the ability of the TCR V beta 6 T hybrids to respond to SEB was regulated by non-V beta TCR elements . cDNA sequencing analyses of the TCR beta- and alpha-chains expressed by the V beta 6 T hybrids and a beta-chain cDNA gene transfer experiment indicated that although J beta, CDR3 beta, J alpha, and CDR3 alpha were not the relevant elements, SEB responsiveness did correlate with the expression of two different members of the V alpha 4 family . A functional analysis of a separate panel of V alpha 4 T hybrids expressing different V beta elements, including V beta 6, specifically associated SEB responsiveness with the V alpha 4, V beta 6 combination . Overall, the data obtained with both panels of T hybrids showed SEB responsiveness in five out of five V beta 6, V alpha 4 T hybrids, and not in either 11 V beta 6 T hybrids expressing a variety of other V alpha elements or four V alpha 4 T hybrids expressing V beta 11, 14, and 15 elements . Thus, our experiments show for the first time a specific, positive qualitative effect of a defined V alpha element on responsiveness to a bacterial superantigen . Finally, this study has identified four new V alpha elements. Clin Exp Dermatol, 1995 May, 20(3), 242 - 3 Troublesome myiasis complicated by peri-nephric abscess; Gibbs S; A normally fit European resident of East Africa developed a staphylococcal peri-nephric abscess following repeated episodes of furuncular myiasis caused by the tumbu fly, Cordylobia anthropophaga . A few lesions had required surgical intervention and one, presumably the source of sepsis, had become infected . There are very few descriptions in the literature of serious complications of myiasis and this is the first report of peri-nephric abscess from this source . This paper discusses the management of the myiasis and what factors determine the variation in host susceptibility and immune response to the infestation. Biol Chem Hoppe Seyler, 1995 May, 376(5), 303 - 9 The domain structure and functional relationships in the bacterial superantigen, SEB; Hayball JD et al.; Staphylococcal enterotoxin B (SEB) has three essential biological properties that appear to be mediated by particular domains of the protein . As a superantigen, SEB triggers the T cell receptor (TcR) of a selected subset of T cells where the beta chain is encoded by particular V beta gene products . T cell triggering is generally dependent upon the ability of SEB to form a ternary complex with the TcR and MHC class II molecules and this interaction is relatively unrestricted by class II polymorphism . The third property of SEB is its potent toxicity; a few nanograms are sufficient to cause vomiting and violent diarrhoea in primates . In this study, we confirm the importance of the amino terminal domain of SEB for stimulation of human T cells . It is clear that the first 138 residues are the minimal mitogenic component of the toxin, and deletion of just seven more residues abrogates all activity . A mutant molecule with an internal deletion of these seven residues (SEB delta 131-138) was mitogenic suggesting that the region can confer stability to the rest of the protein, but does not include contact sites for either class II or the TcR . We further show that the disulphide loop is not essential for T cell recognition and that each of our mutants binds class II molecules with reduced affinity and is subtly variant in the pattern of TcR that it stimulates. Toxicol Pathol, 1995 May-Jun, 23(3), 262 - 8 Aerosolized staphylococcal enterotoxin B-induced pulmonary lesions in rhesus monkeys (Macaca mulatta); Mattix ME et al.; The pathology of aerosolized staphylococcal enterotoxin B (SEB) was studied in the nonhuman primate . Six juvenile rhesus monkeys that received multiple lethal inhaled doses of SEB developed diarrhea and vomiting within 24 hr followed by depression, dyspnea, and shock . Three of 6 animals died by 52 hr . The most striking gross lesion in all 6 monkeys was diffuse severe pulmonary edema . Histologically, edema fluid was present within the peribronchiolar, peribronchial, and perivascular interstitium, alveolar septa, and alveoli . The adventitia of pulmonary vessels was infiltrated by lymphocytes, macrophages, and fewer neutrophils . Numerous large lymphocytes with occasional mitotic figures were within pulmonary vessels, often occluding alveolar capillaries . These cells were strongly immunoreactive with monoclonal antibodies against CD3, establishing them as T cells . Ultrastructurally, endothelial cell junctions were intact, and endothelial cells and type I pneumocytes contained numerous pinocytotic vesicles . Alveolar septal interstitial spaces were expanded by edema . The mechanism of these SEB-induced pulmonary lesions was not determined . We hypothesize that cytokine production by activated T cells may have caused vascular permeability changes leading to widespread pulmonary edema and shock. J Heart Valve Dis, 1995 May, 4(3), 284 - 7 Experimental and clinical evaluation of formalin containing pericardial bioprostheses for replacement of infected valves; Garcia-Bengoechea JB et al.; In 1988 we quantified the adherence of two Staphylococcus epidermidis strains to glutaraldehyde-fixed bovine pericardium and teflon . The pericardium was used with and without prior rinsing to remove the preservative formaldehyde . Bacterial adherence was not detected on non-rinsed pericardium, and it was significantly less on rinsed pericardium than on teflon (p < 0.001) . In view of these results, we have since then implanted 31 pericardial bioprostheses without rinsing them in 29 patients with active bacterial endocarditis . Valve infection reoccurred in two patients (6.7%) and two patients developed early periprosthetic leaks in the absence of re-infection . No adverse clinical or biochemical findings attributable to residual aldehydes have been observed. Glycobiology, 1995 May, 5(3), 327 - 33 Digalactosylceramide is the receptor for staphylococcal enterotoxin-B in human kidney proximal tubular cells; Chatterjee S et al.; We have characterized a glycosphingolipid (GSL) receptor for Staphylococcus enterotoxin-B (SEB) in cultured human kidney proximal tubular (PT) cells . Solid-phase binding of {125I}SEB to the GSL receptor was concentration dependent and was not displaceable by two structurally related toxins, such as staphylococcal enterotoxin-A and toxic shock syndrome toxin-1 . Rat kidney cells did not bind {125I}SEB . However, when the rat kidney cells were pre-incubated with digalactosylceramide, there was a concentration-dependent binding of {125I}SEB . Trimethylsilyl derivatization of methyl glycosides, followed by gas-liquid chromatography-mass spectrometry (GC-MS), revealed that galactose was the major sugar component of this putative receptor GSL . The sphingosines present in this GSL were d18:2, d22:2 and d23:0; the fatty acids present were palmitate, oleate and stearate . Permethylation of alditol acetates and GC-MS revealed two predominant sugars, namely 2, 3, 4 and 6 tetramethylgalactital and 2, 3 and 6 trimethylgalactital . The GSL receptor for SEB was sensitive to alpha-galactosidase, and resistant to beta-galactosidase and beta-glucosidase . Taken together, our studies reveal that the tentative structure of the receptor for SEB in human kidney PT cells is CerGal alpha 1-->4Gal . In summary, we have identified a GSL as one of the binding sites of SEB, a food-borne toxin . We believe that our finding may open up rational approaches for the therapy of SEB-induced glycopathology in man. Acta Derm Venereol, 1995 May, 75(3), 218 - 21 In vitro T cell response to staphylococcal enterotoxin B superantigen in chronic plaque type psoriasis; Bour H et al.; Recent studies have demonstrated the important role of CD4+ T cells in the pathophysiology of psoriasis . One of the current hypotheses is that triggering of the psoriatic inflammatory process could be secondary to CD4+ T cell activation by bacterial superantigens in the skin . In this study, IL-2-derived T cell lines were recovered from the blood and the skin of 4 patients with chronic plaque type psoriasis and of 2 patients with allergic contact dermatitis (ACD) . Blood and skin T cell lines were tested for their ability to proliferate in vitro to staphylococcal enterotoxin B (SEB) presented by MHC class II expressing antigen-presenting cells . The results showed a significantly higher SEB-induced T cell proliferation in skin T cell lines as compared to blood T cell lines in 3 out of 4 psoriatic patients and in one of the 2 ACD patients . No difference between the skin and blood T cells for their response to phytohemagglutinin was observed . Furthermore the blood T cell lines from both patients and control individuals responded equally well to SEB . Thus psoriatic skin T cell lines were characterized by an enrichment in SEB-responding T cells . Since similar enhancement of SEB-responsive T cells was occasionally found in ACD patients, we propose that SEB could be an environmental factor associated with rather than responsible for psoriatic inflammation. Immunology, 1995 May, 85(1), 57 - 62 Superantigens and conventional antigens induce different responses in alpha beta T-cell receptor transgenic mice; Blankson JN et al.; While superantigens such as staphylococcal enterotoxin B (SEB) have been shown to induce both clonal deletion and clonal anergy, it is still not known why tolerance rather than memory is induced . To address this issue, we tested the proliferative capacity of T cells from ovalbumin (OVA)-specific alpha beta T-cell receptor transgenic mice primed with either SEB emulsified in complete Freund's adjuvant (CFA) or with OVA peptide, the specific antigen, in CFA . By contrast cells from mice primed with SEB in CFA appeared to be anergic in that they were hyporesponsive to OVA peptide as well as to SEB . The anergic cells could respond to phorbol myristate acetate (PMA) and ionomycin, suggesting that a proximal signal transduction step was affected . Cells from transgenic mice primed with OVA peptide and CFA were not anergic and in fact displayed an enhanced response when they were challenged with OVA in vitro . Thus, when the two antigens are emulsified in CFA and then injected subcutaneously, they behave very differently: the superantigen SEB induces anergy whereas the conventional antigen OVA induces a memory type of response. Clin Nucl Med, 1995 May, 20(5), 395 - 7 Tc-99m leukocyte scintigraphy in infective endocarditis; Adams BK; A 56-year-old man with Staphylococcal aureus septicemia and clinically suspected infective endocarditis was imaged using Tc-99m HMPAO leukocytes . Although abnormal uptake was seen at 3 hours after injection, 24-hour images demonstrated marked concentration of radiolabeled leukocytes in a myocardial abscess and large posterior parietal infarct . In addition, multiple splenic infarcts were shown . The Tc-99m labeled leukocyte scan proved to be an excellent whole body screening procedure for diagnosing sites of infection and infarction in this patient. J Clin Microbiol, 1995 May, 33(5), 1385 - 8 Value of terminal subcultures for blood cultures monitored by BACTEC 9240; Shigei JT et al.; Blood cultures collected in BACTEC Plus Aerobic/F bottles and BACTEC Plus Anaerobic/F bottles were monitored for 5 days by BACTEC 9240 and subsequent terminal subcultures . Of the 13,471 bottles subcultured, 11.0% (1,477 of 13,471) were culture positive . Of these, 94.0% (1,388 of 1,477) were detected by BACTEC 9240; the additional 6.0% (89 of 1,477) were considered to be false negatives by BACTEC 9240 since they were detected by terminal subculture only . The false-negative bottles consisted of 17 BACTEC Plus Aerobic/F and 72 BACTEC Plus Anaerobic/F bottles, accounting for 2.2 (17 of 786) and 10.4% (72 of 691) of the total positive aerobic and anaerobic bottles, respectively . The positive blood culture bottles most frequently not detected by BACTEC 9240 grew Pseudomonas spp . (24), Staphylococcus spp . (21), and yeasts (24) . Of the 86 blood cultures represented by the 89 false-negative bottles, 41 would not have been identified as positive since the other bottle in the blood culture set was either a false negative or a true negative . In general, terminal subcultures of false-negative BACTEC bottles had heavy growth, indicating that BACTEC Plus media were able to support the growth of microorganisms, but the BACTEC 9240 instrument was unable to detect this growth. Br J Surg, 1995 May, 82(5), 677 - 80 Influence of laparoscopic and conventional cholecystectomy upon cell-mediated immunity; Griffith JP et al.; Surgery, trauma and anaesthesia induce a state of transient immunosuppression . Laparoscopic cholecystectomy has several well documented clinical advantages over traditional cholecystectomy and provokes a lower acute phase response, thought to be a result of the smaller wound size . The influence of laparoscopic cholecystectomy (21 patients) and conventional open cholecystectomy (13 patients) upon components of the cell-mediated immune system was investigated . Cell-mediated immunity was studied by in vitro assays of T lymphocyte proliferation to different mitogens, and by natural killer cell cytotoxicity using a standard 51Cr release assay . Blood samples were taken before and 24 h after the start of the operation . In the sample taken after operation there was significant depression of T lymphocyte proliferation to phytohaemagglutinin (stimulation index 149.4 versus 33.3, P < 0.002), staphylococcal enterotoxin B (85.2 versus 52.6, P = 0.01) and toxic shock syndrome toxin (48.4 versus 14.8, P = 0.08) in the group of patients who underwent open surgery, but not in the group treated by laparoscopic surgery . There was a small but statistically insignificant decrease of natural killer cell cytotoxicity in both groups of patients . These findings suggest that laparoscopic cholecystectomy causes less depression of cell-mediated immunity than open cholecystectomy. Int Arch Allergy Immunol, 1995 May-Jun, 107(1-3), 179 - 82 Staphylococcal enterotoxin B affects in vitro IgE synthesis, interferon-gamma, interleukin-4 and interleukin-5 production in atopic eczema; Neuber K et al.; Peripheral blood mononuclear cells from patients with atopic eczema (AE) stimulated with the 'superantigen' Staphylococcus enterotoxin B (SEB) secreted significantly more interleukin (IL)-4 and IL-5 as well as IgE, and markedly less interferon-gamma than those from healthy controls . Our results support the assumption that SEB produced by S . aureus colonizing the skin of patients with AE may induce expansion of IL-4- and IL-5-producing Th2 clones, leading to increased IgE synthesis and eosinophil activation. Br J Ophthalmol, 1995 May, 79(5), 473 - 5 Rapid diagnosis of ocular herpes simplex infections; Asbell PA et al.; BACKGROUND--The Surecell herpes (HSV) test kit is a test for detecting the presence of herpes simplex viral antigen by means of a monoclonal antibody based immunoassay . The test has proved to be highly sensitive and specific in diagnosing genital, oral, and dermatological herpes infections . METHODS--In this study, samples from patients with ocular keratitis were evaluated by tissue cultures and the Surecell test . The eyes of New Zealand rabbits were then inoculated with HSV type 1 acute keratitis, acute Staphylococcus keratitis, and HSV type 1 postkeratitis (healed corneas) . Tear film samples collected from each eye with a cotton swab were evaluated by routine culture (A-549 monolayers) and by the Surecell test with and without prior placement of the swab in Hank's medium . RESULTS--The Surecell system had a 70% sensitivity and a 100% specificity in the detection of HSV antigen in ocular infections, and was shown to be a quick, efficient, and accurate method of testing for HSV antigen in humans . CONCLUSION--These results from humans and rabbits indicate that the Surecell test, which requires no special equipment, can be a useful in office adjunct in the clinical diagnosis of ocular herpes simplex. Immunol Lett, 1995 May, 46(1-2), 9 - 14 Lethally irradiated normal strains of mice radioprotected with SCID bone marrow develop sensitivity to low doses of staphylococcal enterotoxin B; Aboud-Pirak E et al.; Normal strains of mice are rendered sensitive to small amounts (3-10 micrograms) of staphylococcal enterotoxin B (SEB) by transplanting bone marrow cells of SCID donor mice to lethally irradiated recipients . Four to 12 weeks post-transplantation, SEB induces 56-100% lethality . Transplantation of normal mouse bone marrow cells, either alone or with the SCID mouse selected bone marrow cells, does not confer SEB sensitivity . These data imply that either irradiation ablates certain cell population(s), that confer resistance to SEB in normal mice (populations that are absent in the SCID donor mice) or that the donor cells selectively repopulate recipients with SEB-sensitive cells . This model will help elucidate the cells, cytokines and the SEB peptide fragments responsible for SEB toxicity and will be useful in identifying promising vaccine candidates and in developing preventive medicines to protect against this potent toxin. Eur Heart J, 1995 May, 16(5), 588 - 602 Identification of high-risk subgroups in infective endocarditis and the role of echocardiography; Erbel R et al.; The outcome of infective endocarditis remains poor . It has an overall mortality of around 30%, rising in high-risk subgroups to 50% and 100% . The prognosis can be improved by identification of high-risk patients and special management . Patients with infective endocarditis are found to be at high risk for death or serious complications when one or more of the following factors exist: old age (especially > 60 years old), delayed diagnosis, staphylococcal infection, aortic valve endocarditis, large valvular vegetation, congestive heart failure, embolization in the central nervous system or coronary artery, prosthetic valve infection, recurrent events, and failed antibiotic therapy . These factors often coexist and interrelate with one another . Early diagnosis and active treatment are critical for a better clinical outcome . However, infective endocarditis is difficult to diagnose because of the atypical clinical manifestations and frequent negative results from blood culture . Echocardiography plays an indispensable role in the diagnosis and management of suspected or known infective endocarditis . By detecting and monitoring certain pathological changes associated with the disease, e.g . vegetation, abscess formation, or valvular destruction, echocardiography helps to diagnose the disease early, to identify patients at high risk, to monitor the patients, and to optimize the timing and mode of surgical intervention . Serious complications can thus be avoided or cured at an early stage and the prognosis significantly improved. Pediatr Pulmonol, 1995 May, 19(5), 256 - 61 Vitamin A status and airway infection in mechanically ventilated very-low-birth-weight neonates; Shenai JP et al.; Vitamin A (retinol) plays an important role in immunity . Respiratory and enteral infections in children are associated with low serum vitamin A concentrations that improve during recovery . To test the hypothesis that airway infection in very-low-birth-weight (VLBW) neonates likewise may be associated with a change in vitamin A status, we examined 20 VLBW neonates (selection criteria: birth weight 700-1300 g, gestational age 26-30 weeks, need for supplemental oxygen and mechanical ventilation for > 72 hr after birth) who were enrolled in the control group of a randomized clinical trial of vitamin A supplementation reported earlier . We studied changes in weekly measurements of plasma concentrations of vitamin A and retinol-binding protein (RBP) during 4 weeks following enrollment in the trial (postnatal day 4) and compared changes between periods with and without airway infections . Seventeen infants had 22 episodes of documented airway infection . Staphylococcus epidermidis was the predominant organism . Plasma vitamin A concentrations decreased during 19 out of 22 . With airway infection (mean change: -4.1 to -18.6 micrograms/dL), while they increased during 37 out of 58 periods without airway infection (mean change: -0.2 to +5.8 micrograms/dl; P < 0.001) . The mean (+/- SD) plasma vitamin A concentrations before, during, 1 week after, and 2 weeks after an episode of airway infection were 20.9 +/- 8.3, 9.7 +/- 4.1, 12.8 +/- 8.9, and 16.2 +/- 7.2 micrograms/dL, respectively . The mean value during airway infection was significantly lower than those before and two weeks after airway infection (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) Mol Microbiol, 1995 May, 16(3), 477 - 84 Plasmid pT181 replication is decreased at high levels of RepC per plasmid copy; Iordanescu S; The replication of staphylococcal plasmid pT181 is indirectly controlled at the level of the synthesis of its replication initiator, RepC . As a result, high levels of RepC synthesis per plasmid copy were expected to lead to autocatalytic plasmid replication, which secondarily would affect host physiology . Surprisingly, RepC overexpression was found to lead to a rapid decrease in pT181 copy number and replication rate . These effects depended on the ratio of RepC to the pT181 replication origin rather than on the absolute amount of RepC in the cell . In a wild-type host, the increase in RepC/plasmid copy also inhibited chromosome replication and cell division . The changes in host physiology did not play any role in the decrease in pT181 replication caused by RepC overexpression since pT181 replication responded in the same way in a host mutant insensitive to the effects of RepC induction . These results suggest that pT181, the prototype of an entire class of plasmids from Gram-positive bacteria, responds to overexpression of its replication initiator by a decrease in plasmid replication. Cell Immunol, 1995 May, 162(2), 315 - 20 Activation of murine T cells by bacterial superantigens requires B7-mediated costimulation; Muraille E et al.; Staphylococcus enterotoxins bind class II MHC molecules on antigen-presenting cells (APC) and stimulate T cells expressing appropriate V beta gene products . Although the role of non-TcR-associated costimulatory receptors during antigen-specific T cell stimulation has been clearly established, the involvement of costimulatory activity in T cell activation by superantigens (SAgs) has been the matter of controversy . The aim of this study was to evaluate the role of the costimulatory-receptor ligand molecules CD28/B7 on bacterial SAg-mediated activation of naive murine T cells . We demonstrate in this report that a combination of monoclonal antibodies to murine B7.1 and B7.2 molecules inhibits the in vitro response of naive T cells to SAgs SEA, SEB, and TSST-1 . The inhibition of T cell responses required simultaneous blocking of B7.1 and B7.2, suggesting that either B7.1 or B7.2 is sufficient to provide costimulatory signals to naive T cells in response to bacterial exotoxins . Inhibition of T cell activation by antibodies to B7-related molecules can be overcome by antibodies to CD28, a finding in agreement with the hypothesis that CD28-mediated signals participate in T cell activation by bacterial SAgs . These observations suggest that, as demonstrated for conventional antigen, T cell activation by SAgs requires the coordinated participation of TcR- and CD28-derived signals. J Immunol, 1995 May 1, 154(9), 4395 - 403 Expression and function of mouse Fas antigen on immature and mature T cells; Nishimura Y et al.; We prepared mAbs specific for the mouse Fas Ag (CD95) and used them to analyze the expression and apoptosis-inducing activity of the Fas Ag on murine immunocytes . Cytofluorometry of mouse bone marrow, thymus, and splenocytes using the mAbs indicated that cells of the T lineage, except for bone marrow cells, expressed Fas Ag on the surface . CD4-CD8- undifferentiated thymocytes expressed low levels of Fas Ag . Immature CD4+CD8+ thymocytes and mature CD4+CD8- and CD4-CD8+ thymocytes were highly positive for Fas Ag . CD4+CD8+ thymocytes were specifically sensitive to the apoptosis-inducing activity of anti-Fas, although CD4-CD8-, CD4+CD8-, and CD4-CD8+ thymocytes were resistant . Spleen T cells were resistant to anti-Fas, whereas they expressed Fas Ag . The superantigen, staphylococcal enterotoxin B (SEB) administered to BALB/c mice, induced clonal expansion and successive clonal deletion of spleen T cells bearing the V beta 8 TCR, which specifically reacts to SEB . Such clonal deletion of V beta 8 T cells was highly suppressed in lpr mice, which have defects in the Fas Ag gene . In SEB-administrated BALB/c mice, expression of Fas Ag was significantly enhanced on V beta 8, but not on V beta 6 T cells, which cannot react to SEB . Moreover, V beta 8 T cells in SEB-primed mice were sensitive to the cell-killing activity of anti-Fas, although V beta 6 T cells were resistant . These findings show that the expression level and apoptosis-inducing activity of Fas Ag on peripheral T cells are directly up-regulated by stimulation through the TCR in vivo. J Immunol, 1995 May 1, 154(9), 4302 - 8 Fas ligand-mediated cytotoxicity is directly responsible for apoptosis of normal CD4+ T cells responding to a bacterial superantigen; Ettinger R et al.; Exposure of naive CD4+ T lymphocytes to superantigens such as staphylococcal enterotoxin B (SEB) induces a strong proliferative response . Prolonged exposure or subsequent restimulation of the responding T cell population with SEB leads to the apoptotic events of activation-induced cell death (AICD) . However, T cells derived from either Fas-deficient lpr or Fas ligand-deficient gld autoimmune mouse strains, fail to undergo AICD under these conditions . Instead, these autoimmune T cells mount a vigorous proliferative response, suggesting a critical role for Fas/FasL interactions in this form of autoapoptosis . In the current study, we found that SEB-induced AICD was tied to the rapid induction of FasL expression in cells constitutively expressing high levels of Fas . Furthermore, the addition of soluble Fas-IgG fusion protein to the SEB-restimulated cultures blocked AICD and resulted in a 2 degrees proliferative response that was comparable in magnitude and kinetics to that of the lpr and gld T cells . The rapid onset of apoptosis in normal T cells subsequent to restimulation with SEB was in direct contrast to the proliferative response of the initial cultures, even though comparable levels of Fas and FasL RNA were found in T cells after 1 degree and 2 degrees challenge . The clonal expansion of the normal T cells responding to the initial SEB stimulation was, however, dramatically compromised when the normal cells were cocultured with an MRL-lpr responder population; addition of soluble Fas-IgG rescued the normal component of the response . Together, these data demonstrate first, that Fas/FasL interactions are intimately tied to superantigen-induced AICD, a form of autocrine cell death, and second, that FasL-mediated cytotoxicity is responsible for the disappearance of normal CD4+ T cells in lpr cocultures. Philos Trans R Soc Lond B Biol Sci, 1995 Apr 29, 348(1323), 27 - 34 Initial studies of the equilibrium folding pathway of staphylococcal nuclease; Wang Y et al.; Spectroscopic methods were used to examine the sequential build up of structure in the denatured state of staphylococcal nuclease . The 'free energy distance' between the native and denatured states was manipulated by altering conditions in solution (for example altering urea or glycerol concentration) and by changing the amino acid sequences . Initial studies employed a fragment of nuclease, referred to as delta 131 delta, which lacks six structural residues from the amino terminus and one structural residue from the carboxy-terminus . Nuclear magnetic resonance analysis of this fragment in solution revealed a modest quantity of dynamic structure which is native-like in character . With the addition of urea, 12 new HN peaks appeared in the 1H-15N correlation spectrum, presumably as a result of the breakdown of residual structure involving the first three beta strands . With the addition of glycerol, there was a rapid increase in the quantity of beta sheet structure detected by circular dichroism spectroscopy . At very high glycerol concentrations, an increase in helical structure became apparent . These data in addition to previously published results suggest that: (i) a beta-meander (strands beta 1-beta 2-beta 3) and the second alpha helix (alpha 2) are among the most stable local structures; (ii) the five-strand beta-barrel forms in a reaction which does not require the presence of several other native substructures; and (iii) the last step on the equilibrium folding pathway may be the formation and packing of the carboxy terminal alpha helix (alpha 3) to give the native state. J Immunol Methods, 1995 Apr 26, 181(2), 233 - 43 Whole blood culture for measuring mitogen induced T cell proliferation provides superior correlations with disease state and T cell phenotype in asymptomatic HIV-infected subjects; Bocchieri MH et al.; Proliferative responses to a panel of mitogens were compared in parallel for two sources of cells, whole blood (WB) and conventionally prepared peripheral blood mononuclear cells (PBMC), obtained from asymptomatic HIV seropositive and control subjects . Weak but statistically significant correlations of the proliferative responses were observed . Use of either lymphocyte source produced significant differences in the proliferative responses between the HIV seropositive and control subjects, but the use of WB was more powerful, with a smaller sample size being required to discriminate between the proliferative responses of the two study groups . Furthermore, proliferative responses using WB gave strong and highly significant correlations with a number of important changes in the surface marker phenotype of the lymphocyte populations in the HIV seropositive subjects including CD4, CD8, CD4:CD8 ratio and certain CD8 subsets, whereas strong correlations were not observed with the PBMC . The response of WB lymphocytes to staphylococcal enterotoxin B (SEB) was highly reproducible and provided the best discrimination between HIV-infected and control subjects . We conclude that the use of WB for measuring lymphoproliferation is easy, rapid, accurate, and discriminative for assessing and following the changes in immune function which occur in HIV seropositive subjects, applicable in the clinical as well as in the research setting. Science, 1995 Apr 21, 268(5209), 403 - 5 Superantigen-dependent, cell-mediated cytotoxicity inhibited by MHC class I receptors on T lymphocytes; Phillips JH et al.; Bacterial superantigens bind with high affinity to major histocompatibility complex (MHC) class II antigens on antigen-presenting cells and with T cell antigen receptor (TCR) beta chains on T lymphocytes, which results in the T cell activation responsible for toxic shock syndrome and food poisoning . Many cytotoxic T lymphocyte (CTL) clones were shown to have receptors for human leukocyte antigen (HLA) class I molecules that inhibited superantigen-induced cytotoxicity against appropriate class I-bearing target cells . One type of inhibitory receptor, NKB1, was present on CD4+ and CD8+TCR alpha beta+ CTL clones and blocked the killing of staphylococcal enterotoxin B (SEB)-coated targets bearing certain polymorphic HLA-B molecules . Expression of HLA-A, -B, and -C molecules on the SEB-coated targets also protected against cytolysis mediated by many NKB1-negative T cell clones, suggesting the presence of additional inhibitory MHC class I receptors . These HLA class I receptors may limit tissue destruction and possibly autoimmunity caused by activated T lymphocytes. EMBO J, 1995 Apr 18, 14(8), 1607 - 14 Potassium-inhibited processing of IL-1 beta in human monocytes; Walev I et al.; Agents that deplete cells of K+ without grossly disrupting the plasma membrane were found to stimulate the cleavage of pro-interleukin (IL)-1 beta to mature IL-1 beta . Agents examined in this study included staphylococcal alpha-toxin and gramicidin, both of which selectively permeabilize plasma membranes for monovalent ions, the ionophores nigericin and valinomycin, and the Na+/K+ ATPase inhibitor ouabain . K+ depletion by brief hypotonic shock also triggered processing of pro-IL-1 beta . The central role of K+ depletion for inducing IL-1 beta maturation was demonstrated in cells permeabilized with alpha-toxin: processing of pro-IL-1 beta was totally blocked when cells were suspended in medium that contained high K+, but could be induced by replacing extracellular K+ with Na+, choline+ or sucrose . To test whether K+ flux might also be important in physiological situations, monocytes were stimulated with lipopolysaccharide (LPS) for 1-2 h to trigger pro-IL-1 beta synthesis, and transferred to K(+)-rich medium . This maneuver totally suppressed IL-1 beta maturation . Even after 16 h, however, removal of K+ from the medium resulted in rapid processing and export of IL-1 beta . Ongoing export of mature IL-1 beta from cells stimulated with LPS for 2-6 h could also be arrested by transfer to K(+)-rich medium . Moreover, a combination of two K+ channel blockers inhibited processing of IL-1 beta in LPS-stimulated monocytes . We hypothesize that K+ movement and local K+ concentrations directly or indirectly influence the action of interleukin-1 beta-converting enzyme (ICE) and, possibly, of related intracellular proteases. Biochemistry, 1995 Apr 18, 34(15), 4909 - 12 Evidence for a molten globule-like transition state in protein folding from determination of activation volumes; Vidugiris GJ et al.; One of the most important, yet elusive, aspects of the protein folding question lies in the nature of the transition state . Direct information about the structural properties of the transition state can be obtained from determination of the activation volumes for the folding and unfolding transitions . The present pressure-jump relaxation study on the folding/unfolding of staphylococcal nuclease reveals that the volume of the protein-solvent system is larger in the transition state than in either the folded or unfolded states . Moreover, the activation volume of folding is much larger than that of unfolding . These results support a molten globule-like model for the transition state of nuclease in which the polypeptide chain is in a collapsed, loosely packed, solvent-excluded structure . In this model, hydrophobic collapse with concomitant desolvation is the rate-limiting step in the folding of the polypeptide chain, and solvent-excluded expansion of the folded state is the rate-limiting step in protein unfolding. FEMS Microbiol Lett, 1995 Apr 15, 128(1), 39 - 44 Typing of Staphylococcus epidermidis strains by random amplification of polymorphic DNA; Marquet-Van Der Mee N et al.; The polymerase chain reaction was used to obtain randomly amplified polymorphic DNA profiles for typing of Staphylococcus epidermidis strains . Epidemiologically unrelated S . epidermidis isolates were screened with randomly amplified polymorphic DNA analysis . The discriminating ability of 45 randomly designed 10-mer primers was assessed . The highest discriminatory power was obtained with the 10-mer oligonucleotide OPAM-12 . In typing a total of 13 unrelated S . epidermidis strains with OPAM-12, 11 different banding profiles were obtained reproducibly by agarose gel electrophoresis . The discriminatory power of the method with OPAM-12 was estimated using the D value of Hunter and Gaston (1988) to be 0.961 . A reproducibility index of 1 was obtained after typing a total of 40 cultures including 12 triplicates and one quadruplicate of the 13 unrelated strains . Following the described procedure, the randomly amplified polymorphic DNA method provided a rapid, simple and reproducible alternative to other S . epidermidis typing systems. Cell Immunol, 1995 Apr 15, 162(1), 26 - 32 Staphylococcal enterotoxin B induces the expression of activation markers on murine memory T cells in the absence of proliferation or lymphokine secretion; Lee WT et al.; Superantigens have been used to study peripheral tolerance in CD4+ T cells . The superantigen SEB induces T cell anergy by promoting the differentiation of SEB-activated virgin T cells into anergic memory T cells . Memory T cells from SEB or antigen-primed mice do not proliferate when they are cultured with SEB . The present studies were performed to determine whether memory T cells fail to interact with SEB antigen-presenting cells or whether SEB promotes incomplete or negative signals in memory T cells . When murine virgin and memory T cells were separated on the basis of CD45RB expression and cultured with SEB-pulsed B cells, SEB induced the expression of CD25, which then mediated proliferation when IL-2 was added to the cultures . In addition, SEB promoted the expression of the CD40L, which is required for T helper cell function . Finally, PMA induced a costimulatory signal leading to the proliferation of these cells . Surprisingly, the agents, i.e., IL-2 and PMA, which induced TM cell proliferation in conjunction with SEB failed to induce lymphokine secretion . However, in the presence of IL-4 plus IL-5, the T memory cells induced the SEB-pulsed B cells to secrete IgM and IgG . These results suggest that memory T cells are not simply unresponsive to SEB but are actively anergized. Proc Natl Acad Sci U S A, 1995 Apr 11, 92(8), 3611 - 5 Differential modulation of Th1- and Th2-related cytokine mRNA expression by a synthetic peptide homologous to a conserved domain within retroviral envelope protein; Haraguchi S et al.; The influence of a synthetic retroviral peptide, CKS-17, on T helper type 1 (Th1)- or Th2-related cytokines was investigated in human blood mononuclear cells . Cells were stimulated with staphylococcal enterotoxin A, anti-CD3 plus anti-CD28 monoclonal antibodies, or lipopolysaccharide to induce cytokine mRNA . mRNA was detected by a reverse transcription-polymerase chain reaction or Northern blot analysis . CKS-17 down-regulated stimulant-induced mRNA accumulation for interferon gamma (IFN-gamma), interleukin (IL)-2, and p40 heavy and p35 light chains of IL-12, a cytokine that mediates development of Th1 response . CKS-17 up-regulated stimulant-induced mRNA accumulation of IL-10 and did not suppress Th2-related cytokine (IL-4, IL-5, IL-6, or IL-13) mRNA expression . A reverse sequence of CKS-17 peptide, used as a control, showed no such action . Anti-human IL-10 monoclonal antibody blocked ability of CKS-17 to inhibit mRNA accumulation for IFN-gamma but not the CKS-17 suppressive activity of IL-12 p40 heavy chain mRNA . Thus, CKS-17-mediated suppression of IFN-gamma mRNA expression is dependent upon augmentation of IL-10 production by CKS-17 . This conserved component of several retroviral envelope proteins, CKS-17, may act as an immunomodulatory epitope responsible for cytokine dysregulation that leads to suppression of cellular immunity. J Biol Chem, 1995 Apr 7, 270(14), 7799 - 808 Further characterization of HeLa DNA polymerase epsilon; Chui G et al.; DNA polymerase epsilon (pol epsilon) from HeLa cells was purified to near homogeneity, utilizing Mono S fast protein liquid chromatography for complete separation from pol alpha . The purified pol epsilon preparation showed two polypeptides of > 200 and 55 kDa and a small amount of active 122-kDa proteolysis product on denaturing polyacrylamide gels . Pol epsilon (as well as pols alpha and delta) is optimally active in 100-150 mM potassium glutamate and 15 mM MgCl2 . Replication factors RF-A and RF-C, proliferating cell nuclear antigen, and Escherichia coli single-stranded DNA binding protein showed no significant effect on this preparation's pol epsilon activity, processivity, or substrate specificity . The size of the pol epsilon transcript for the catalytic subunit (> 200 kDa) was investigated in both normal human fibroblasts and HeLa cells . A 7.7-kilobase transcript was detected which was 5-16-fold more prevalent in proliferating than in quiescent HeLa cells . No significant difference in the level of pol epsilon transcript in HeLa cells or fibroblasts was seen after ultraviolet irradiation . Mouse polyclonal antiserum was produced to a 144-amino acid fragment of pol epsilon fused to staphylococcal protein A . This non-neutralizing polyclonal antiserum specifically recognized the catalytic subunit of pol epsilon by immunoblotting, but not that of pol alpha, beta, or delta . In addition, mouse polyclonal antiserum raised against column-purified pol epsilon was able to recognize and to neutralize pol epsilon, and a mouse monoclonal antibody was raised which was able to recognize specifically the catalytic subunit of pol epsilon. Biochim Biophys Acta, 1995 Apr 5, 1248(1), 27 - 34 Identification of the active site histidine in Staphylococcus hyicus lipase using chemical modification and mass spectrometry; Boots JW et al.; Staphylococcus hyicus lipase is a serine hydrolase . In order to identify the active site histidine of S . hyicus lipase we have chemically modified S . hyicus lipase with 1-bromo-octan-2-one . The enzyme is rapidly inactivated by this inhibitor with a half-time of 578 s at pH 6.5 and 30 degrees C . Addition of the enzyme's cofactor calcium increases the inactivation rate approx . 2-fold . When n-hexadecylphosphocholine, a non-hydrolysable substrate analogue, is added the inactivation rate decreases about 3-fold, suggesting that a residue in the active site of S . hyicus lipase is involved in the inactivation reaction . Inactivation of S . hyicus lipase with 14C-labelled 1-bromo-octan-2-one shows that 1.4 moles of inhibitor per mole of lipase are incorporated . The results of an electrospray mass spectrometric study of the inactivated enzyme are consistent with this finding . In order to identify the modified residue, both the inactivated and the unmodified lipase were digested with cyanogen bromide followed by trypsin . The resulting peptides were analysed using HPLC and fast atom bombardment mass spectrometry . The results allow the modified residue to be assigned to the peptide Gly597-Lys612 . Collision induced dissociation mass spectrometry allowed the modified residue to be identified as His-600 . From these results we conclude that this residue forms part of the catalytic triad of S . hyicus lipase. Biochemistry, 1995 Apr 4, 34(13), 4316 - 24 X-ray crystal structures of staphylococcal nuclease complexed with the competitive inhibitor cobalt(II) and nucleotide; Loll PJ et al.; Two crystal structures of ternary complexes of staphylococcal nuclease, cobalt(II), and the mononucleotide pdTp are reported . The first has been refined at 1.7 A to a crystallographic R value of 0.198; the second, determined from a crystal soaked for 9 months in a slightly different mother liquor than the first crystal, has been refined at 1.85 A to an R value of 0.174 . In the first structure, the cobalt ion is displaced 1.94 A from the normal calcium position, and the active site is dominated by a salt bridge between Asp-21 and Lys-70 from a symmetry-related molecule in the crystal lattice . The Co2+ ion appears unable to displace this lysine; consequently, the metal is bound in a vestibular site adjacent to the calcium site . The metal-binding pocket in the second structure adopts a configuration similar to that of the calcium complex, with the cobalt ion binding only 0.36 A from the calcium position . However, an inner sphere water seen in the calcium structure is missing from this structure . The cobalt ion in the second structure appears to be loosely or transiently coordinated within the calcium binding pocket, as evidenced by the high value of its refined thermal factor . Loss of catalytic activity for cobalt(II)-substituted nuclease is perhaps due to its inability to bind this inner sphere water. Nat Immun, 1995 Apr, 14(4), 188 - 97 Human intestinal V delta 1+ T cells obtained from patients with colon cancer respond exclusively to SEB but not to SEA; Maeurer M et al.; The function and activation requirements for gamma delta T cells residing in the human intestine are still poorly defined . We have established two gamma delta + T cell tumor-infiltrating lymphocyte (TIL) lines derived from a primary colorectal cancer (gamma delta TIL No . 3481), and from a colorectal cancer lesion metastatic to the liver (gamma delta TIL No . 7279) . Both gamma delta TIL lines used exclusively the V delta 1 segment and predominantly the V gamma 2 segments of the T cell receptor (TCR) variable regions and lysed allogeneic colorectal cancer cell lines, e.g . HCT 116, but not natural killer/lymphokine-activated-killer-sensitive target cell lines, e.g . K562 or Daudi . gamma delta T cell effector functions were evaluated on the basis of their recognition and cytolysis of colorectal cancer cell lines, T cell proliferation, and interferon (IFN)-gamma release . Both gamma delta T cell lines exhibited similar responses to the staphylococcal superantigens (SE) A and B . SEA and SEB did not influence target cell cytolysis of colon cancer targets . Neither gamma delta + T cell line responded to SEA as measured by IFN-gamma release of T cell proliferation . In marked contrast, SEB induced T cell proliferation and IFN-gamma release in the absence of stimulator cells . SEB induced secretion of IFN-gamma by gamma delta T cells which could be augmented if stimulator cells (HCT116) were also added to gamma delta T cells . On the basis of these data, we suggest that intestine-derived V delta 1/V gamma 2+ T cells respond preferentially to SEB and not to SEA . This disparity may reflect the inherently higher affinity of individual gamma delta TCR subsets for SEB but not to SEA and/or indicate that a subset of gamma delta + TILs in patients with colon cancer may be preferentially expanded with a TCR rearrangement favoring the interaction with SEB . The induction of IFN-gamma release and proliferative gamma delta + T cell responses by SEB suggests a pivotal role for intestinal gamma delta T cells in mediating immune responses against bacteria and bacterial products, or potentially in anti-tumor-directed immunity . Such immune responses mediated by gamma delta + T cells may take place prior to the maturation of antigen-specific MHC-restricted alpha beta + T cell responses. Bioorg Med Chem, 1995 Apr, 3(4), 437 - 45 Targeting peptide nucleic acid-protein conjugates to structural features within duplex DNA; Norton JC et al.; A convenient small scale synthesis has been developed for obtaining peptide nucleic acid oligomers (PNAs) . PNAs have been conjugated to a protein, staphylococcal nuclease, through disulfide exchange between a cysteine at the 3'-(carboxy) end of the PNA and an introduced cysteine on the surface of the nuclease . Site specific DNA cleavage by the attached nuclease has been used to examine the Watson-Crick hybridization of the PNAs to duplex DNA . Substantial affinity cleavage occurred when target sites contained inverted repeats which have the potential to form non B-DNA structures such as cruciforms . No affinity cleavage was observed at a site lacking apparent potential for non B-DNA structures . These results indicate that the Watson-Crick hybridization of PNAs to duplex DNA by strand displacement is favored by the presence of potential alternative secondary structures within the target sequence. Infect Immun, 1995 Apr, 63(4), 1223 - 8 In vitro modulation of keratinocyte-derived interleukin-1 alpha (IL-1 alpha) and peripheral blood mononuclear cell-derived IL-1 beta release in response to cutaneous commensal microorganisms; Walters CE et al.; The ability of a range of skin commensal microorganisms to modulate interleukin-1 (IL-1) release by cultured human keratinocytes and peripheral blood mononuclear cells (PBMCs) was investigated by a combination of enzyme-linked immunosorbent assays and bioassays . Three fractions (formaldehyde-treated whole cells, culture supernatants, and cellular fractions) were prepared from Propionibacterium acnes, Propionibacterium granulosum, Staphylococcus epidermidis, Staphylococcus capitis, Staphylococcus hominis, and Malassezia furfur serovar B . The levels of immunochemical IL-1 alpha released by cultured keratinocytes during coincubations with these microbial fractions ranged from 0 to 136 pg/ml and were maximal after 72 h . No microbial fraction consistently upregulated immunochemical IL-1 alpha release by freshly isolated keratinocytes from two donors and a transformed cell line, all of which produced the cytokine constitutively to various extents . Bioassays revealed that most of the IL-1 released was biologically inactive . In contrast, whole cells of formaldehyde-treated P . granulosum and S . epidermidis significantly stimulated release of IL-1 beta by PBMCs from three donors compared with the negative control (culture medium) . Release was maximal at 24 h . Coincubation with intact cells of the yeast M . furfur significantly decreased levels of IL-1 beta below the values for the negative control by PBMCs from all three donors . There was good correlation between bioassay data and immunoassay data for IL-1 beta, and the depressive effect of M . furfur cells on cytokine production by all three cultures of PBMCs was mirrored in the levels of bioactive cytokine . This reduction in IL-1 beta release by PBMCs by M . furfur may provide an explanation why dermatoses thought to be caused by this yeast are essentially noninflammatory or only mildly inflammatory. Infect Immun, 1995 Apr, 63(4), 1158 - 64 Anti-gamma interferon and anti-interleukin-6 antibodies affect staphylococcal enterotoxin B-induced weight loss, hypoglycemia, and cytokine release in D-galactosamine-sensitized and unsensitized mice; Matthys P et al.; Administration of staphylococcal enterotoxin B (SEB) to BALB/c mice was found to induce a cytokine release syndrome hallmarked by weight loss and hypoglycemia . A neutralizing monoclonal antibody against gamma interferon (IFN-gamma) given before SEB counteracted weight loss and prevented hypoglycemia . This protective effect of anti-IFN-gamma antibody was associated with decreased IFN-gamma levels in serum; tumor necrosis factor (TNF) and interleukin-6 (IL-6) levels remained unchanged . A monoclonal anti-IL-6 antibody, known for its ability to cause accumulation of biologically active IL-6 in the circulation, did not modify SEB-induced body weight loss or hypoglycemia . Levels of TNF, IFN-gamma, and IL-6 in serum were all more elevated in anti-IL-6-treated mice than in corresponding SEB-challenged control mice . In D-galactosamine-sensitized mice, SEB-induced weight loss but not hypoglycemia was more severe, resulting mostly in death within 24 h . Higher levels of biologically active TNF and IFN-gamma in serum were noted in these mice than in mice receiving SEB only . In D-galactosamine-sensitized mice, anti-IFN-gamma antibody did prevent hypoglycemia but failed to reduce the severity of the syndrome . Again, TNF levels in anti-IFN-gamma-treated mice remained unchanged . Pretreatment with anti-IL-6 antibody temporarily attenuated SEB-induced hypoglycemia in sensitized mice . Thus, at 6 h post-SEB injection, anti-IL-6-treated mice were less hypoglycemic than corresponding controls . However, at 24 h, hypoglycemia was significantly aggravated . Concomitantly, IL-6 levels were dramatically increased . Neither anti-IFN-gamma nor anti-IL-6 antibody treatment modulated mortality levels in D-galactosamine-sensitized mice . The data obtained with anti-IFN-gamma antibody clearly indicate that endogenous IFN-gamma is instrumental in bringing about hypoglycemia and body weight loss in mice exposed to SEB but also that hypoglycemia is not a crucial determinant of mortality in D-galactosamine-sensitized mice . The data obtained with anti-IL-6 antibody indicate that endogenous IL-6 is involved in regulating the levels of TNF and IFN-gamma in serum. Immunology, 1995 Apr, 84(4), 528 - 35 Superantigen-induced peripheral T-cell deletion: the effects of chemical modification of antigen-presenting cells, interleukin-4 and glucocorticoid hormones; Ayroldi E et al.; Experiments were performed to evaluate the role of antigen-presenting cells (APC) and the effect of interleukin-4 (IL-4) and glucocorticoid hormone (GCH) exposure on the in vitro deletion of CD4+ CD8- and CD8+ CD4- T cells by staphylococcal enterotoxin B (SEB) . APC fixation with the chemical cross-linker 1-ethyl-3-(3-dimethyl-aminopropyl) carbodiimide (ECDI) inhibited their capacity to induce SEB-specific deletion of mature T lymphocytes . Deletion was not influenced by treatment with anti-CD28 antibodies, which modulate T-cell activation . However, it was augmented by IL-4, known to counteract anti-CD3- and GCH-induced thymocyte apoptosis, and was inhibited by dexamethasone (DEX) . These results indicate that metabolically active APC are required for deletion of antigen-specific mature T cells and suggest that IL-4 and GCH can modulate this phenomenon in vitro. Antimicrob Agents Chemother, 1995 Apr, 39(4), 834 - 8 Tolerability, kinetics, and efficacy of subconjunctival pefloxacin in pigmented rabbits; Marrakchi-Benjaafar S et al.; Pefloxacin has been shown to have good intraocular penetration when given systemically . In order to extend its clinical use, we have assessed the tolerability, kinetics, and efficacy of subconjunctival pefloxacin in phakic pigmented rabbits . The tolerability of a single subconjunctival injection of pefloxacin (0.8, 1.6, 8, or 16 mg in 0.2 ml) in the right eyes of eight rabbits was evaluated by clinical and histopathological examination . The 0.8-mg dose of pefloxacin was well tolerated . The kinetics was evaluated after a single subconjunctival injection of 0.8 mg in 18 rabbits . Animals were sacrificed at 1, 3, 5, 7, 12, or 18 h postinjection . Drug concentrations were measured by high-performance liquid chromatography . Pefloxacin was found in the cornea (maximum concentration, 18.13 micrograms/ml; half-life, 3.92 h) and in the aqueous humor (maximum concentration, 3.40 micrograms/ml; half-life, 2.14 h) . Pefloxacin did not penetrate into the vitreous humor by this route . The efficacy was evaluated in an experimental model of staphylococcal corneal ulcers in eight rabbits which received two subconjunctival injections of 0.8 mg of pefloxacin at 16 and 24 h after intrastromal inoculation . The results (expressed as mean log10 CFU per milliliter +/- standard deviation) showed that pefloxacin significantly (P < 0.001) reduced the bacterial counts (4.39 +/- 0.97) compared with those in control eyes (6.46 +/- 0.69) . For phakic eyes, subconjunctival pefloxacin might be of value for the treatment of corneal ulcers . Further studies are required to determine its penetration into the vitreous humor of aphakic eyes. Br J Haematol, 1995 Apr, 89(4), 698 - 703 In vitro inhibition of tumour necrosis factor-alpha and interleukin-6 production by intravenous immunoglobulins; Toungouz M et al.; In vitro data about the action of pooled immunoglobulins (Ig) on cytokine (CK) production are controversial . The recent finding of natural antibodies against staphylococcal toxins neutralizing superantigen-induced activation prompted us to design an assay determining their ability to modulate staphylococcal enterotoxin B (SEB) induced CK production (IL-6 and TNF-alpha) . Presence of anti-SEB antibodies was demonstrated by a dot-blot assay in the three preparations tested . Preincubation of SEB with pooled Ig prior to addition into the test tube containing PBMCs (neutralizing condition) resulted in a strong inhibition of both TNF-alpha and IL-6 release (TNF alpha: 59 +/- 5% inhibition, P < 0.0001; IL-6: 71 +/- 7% inhibition, P < 0.0001, n = 15) . Anti-CD3 MoAb-induced CK production was not modified . During our study it was found that experimental conditions were critical to observe this inhibitory effect . Reversing the previous procedure by adding PBMCs into the test tube containing pooled Ig mixed with SEB resulted in a marked induction of TNF-alpha and IL-6 production . The same observation was made when pooled Ig solely was added (coating condition) . F(ab')2 fragments of pooled Ig displayed similar inhibitory capacity when added in neutralizing condition, indicating that the mechanism involved was not Fc dependent . The fragments lost the activating properties of intact Ig when incubated in coating condition, showing that Fc receptor activation occurs in this setting . The present work demonstrates that inhibition of SEB-induced CKs release by pooled Ig can be achieved by SEB neutralization, provided that the experimental conditions avoid activation through the Fc receptor . It can be assumed that similar mechanisms take place in some clinical conditions during which pooled Ig are infused. Ann Rheum Dis, 1995 Apr, 54(4), 298 - 304 Staphylococcal enterotoxin B increases the severity of type II collagen induced arthritis in mice; Wooley PH et al.; OBJECTIVE--To observe the influence of T cell subset changes on the development of experimental arthritis, by using the bacterial superantigen staphylococcal enterotoxin B (SEB) to modulate the T cell repertoire during the arthritogenic response to type II collagen (CII) in vivo . METHODS--DBA/1 mice were injected with SEB before immunisation with CII, and assessed for the development of collagen induced arthritis (CIA) and an immune response to CII . Mice with established arthritis were also treated therapeutically with SEB . Flow cytometry was used to evaluate the effect of the therapy on T cell subsets and T cell receptor (TCR) V beta expression . RESULTS--Mice injected with SEB developed arthritis significantly faster than saline treated control animals, and developed more severe clinical features . Mice treated with SEB after the onset of CIA were also observed to progress more rapidly to a severe arthritis than mice treated with saline alone . The level of anti-CII antibody was not affected by SEB injection . Flow cytometric analysis of TCR expression in mice 21 days after injection of CII showed decreased expression of V beta 6 and V beta 8 cells in SEB treated mice, compared with collagen immunised control mice . Injection of SEB alone caused a decrease in V beta 8, but not V beta 6 T cells compared with the values in normal DBA/1 mice . No significant variations in the T cell repertoire were detected 70 days after CII immunisation . CONCLUSIONS--Treatment with the bacterial enterotoxin SEB before the induction of arthritis did not suppress the immunological or arthritogenic response to CII in DBA/1 mice, despite the modulation of the V beta 8 T cell subset . Treatment of mice with established arthritis using SEB provoked a more severe disease course. Arch Dis Child, 1995 Apr, 72(4), 325 - 9 Morbidity using subcutaneous ports and efficacy of vancomycin flushing in cancer; Rubie H et al.; An evaluation of totally implanted venous access systems inserted in 163 consecutive children with cancer is reported . From 1988 to 1994, 180 subcutaneous ports were inserted in children more than 1 year old . Initial diagnosis was acute leukaemia (n = 79), non-Hodgkin's lymphoma (n = 33), and solid tumour (n = 51) . Median age was 85 months . All venous procedures were performed through the device . Chemotherapy was either moderate (n = 13) or intensive (n = 119) or very intensive (n = 48), including 16 patients undergoing marrow transplantation . Cumulative venous access totalled 55,770 patient days with a mean of 305 days/subcutaneous port . The cause of device removal was, end of treatment (n = 111), death due to malignancy (n = 20), catheter related infection (n = 7), and occlusion of the system (n = 4) . Mechanical complications occurred in 19 ports; 16 were due to clots, of which 14 were cleared with instillation of urokinase . Documented infectious episodes occurred in 47 ports, recurred once in 14, and twice in five cases . Among these infections, 47 were septicaemic; 31 due to Staphylococcus epidermidis . Twenty seven of initial septic episodes were considered to be catheter related; the rate was 15%/subcutaneous port or 0.05/100 catheter days . Risk factors for the development of a first infection were age below 4 years and the time of use . Since February 1993, vancomycin (50 micrograms/ml) has been given and this has reduced the rate of S epidermidis infection from 26/83 subcutaneous port to 4/97 . Life table analysis showed that the infection free interval for staphylococcus was significantly better after this technique ws initiated (log rank rest=0.02) . Time saved was approximately 30minutes/patient/week compared with external catheters, or 45 hours/month for the cohort of children treated . Subcutaneous ports in paediatric cancer patients are reliable, safe, and durable and may offer an attractive alternative to external catheters for prolonged venous access and intensive treatment. J Neurol Neurosurg Psychiatry, 1995 Apr, 58(4), 444 - 6 Comparison of rates of infection of two methods of emergency ventricular drainage; Kim DK et al.; The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review . Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate . The difference in the infection rate between the two methods was statistically significant (P < 0.015) . Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection . Most infections from either method were caused by a coagulase negative staphylococcus . The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies. Nutr Clin Pract, 1995 Apr, 10(2), 60 - 6 Femoral catheters increase risk of infection in total parenteral nutrition patients; Harden JL et al.; Central venous access for the administration of total parenteral nutrition is usually achieved via the subclavian or internal jugular veins . Although a high incidence of complications has been reported with the use of femoral catheters for central venous access, this route has been used when traditional central venous access is contraindicated . We retrospectively reviewed 171 patients who received total parenteral nutrition via a central venous triple-lumen catheter and compared the rates of infections in femoral vs nonfemoral access . A literature review was performed to identify associated complications of and appropriate indications for femoral catheter use . In the 171 patients studied, 355 triple-lumen catheters were placed; these included 331 nonfemoral catheters and 24 femoral catheters . Femoral catheters were placed in nine patients . Femoral catheters had a greater incidence of positive tips (42% vs 6.9%, p < .001) and related bacteremia (16.7% vs 1.8%, p = .002) than did nonfemoral catheters . The organisms most commonly isolated from the blood and catheter tips of both catheter access sites were methicillin-resistant Staphylococcus epidermidis and Candida . The use of femoral catheters for central venous access for total parenteral nutrition administration results in an increased risk of infectious complications. J Bone Joint Surg Am, 1995 Apr, 77(4), 524 - 9 Delayed infections following posterior spinal instrumentation for the treatment of idiopathic scoliosis; Richards BS; Ten patients who had been managed with posterior spinal arthrodesis and Texas Scottish Rite Hospital instrumentation because of idiopathic scoliosis had a delayed deep wound infection at an average of twenty-five months after the operation . The signs of infection included spontaneous drainage in eight patients and fluctuance in two patients . In addition, six patients--including five of the eight who had drainage--had mild pain in the back . The average erythrocyte sedimentation rate was thirty-nine millimeters per hour (range, nineteen to eighty-one millimeters per hour) . The instrumentation was removed from all of the patients . In two patients, a pseudarthrosis that had not been noted on preoperative radiographs was noted intraoperatively; in both patients, the pseudarthrosis occurred at a level at which two hooks had been placed in one intervertebral space . Primary closure was performed in seven patients, and delayed primary closure was performed on the third postoperative day in three patients . All wounds healed uneventfully . Cultures of specimens taken from deep within the wound were positive for Propionibacterium acnes (five patients), Staphylococcus epidermidis (two patients), a rare coagulase-negative Staphylococcus species (one patient), or Micrococcus varians (one patient) . No organisms grew on culture of the specimen obtained from the remaining patient . Propionibacterium acnes required an extended period of incubation before identification . Antibiotics were administered parenterally to all of the patients after the removal of the hardware, and this treatment was followed by oral administration of antibiotics for nine of the patients . We suspect--but can not prove--that several of the delayed infections resulted from intraoperative seeding and remained subclinical for an extended period of time. Arch Surg, 1995 Apr, 130(4), 446 - 7 Tropical pyomyositis presenting in the upper extremity; Michaels BM et al.; Tropical pyomyositis is a staphylococcal infection, usually of a single large muscle, most commonly seen in young men in tropical regions . The following presents a case of tropical pyomyositis in a 62-year-old man that affected all four extremities, including the muscles of the forearms . Computed tomography was a useful guide for directing surgical explorations . To decrease the degree of disability from the multiple operative sites, we successfully used limited longitudinal incisions and conservative debridements. Am J Kidney Dis, 1995 Apr, 25(4), 593 - 6 Catheter-related sepsis complicating long-term, tunnelled central venous dialysis catheters: management by guidewire exchange; Shaffer D; Standard therapy of catheter-related sepsis of long-term, tunnelled, silicone dialysis catheters is catheter removal, parenteral antibiotics, and catheter replacement in a new venous site after documented clearing of bacteremia . This leads to loss of future venous access sites . Thirteen consecutive cases of dialysis catheter-related sepsis in 10 patients successfully managed by guidewire exchange with preservation of the same central venous access site are reported . Although the most common cause of catheter sepsis in this series was coagulase-negative staphylococcus, guidewire exchange also was successful in cases due to gram-negative rods and yeast . To preserve future venous access sites in the chronic hemodialysis population, long-term, tunnelled dialysis catheter-related sepsis should be managed by a short course of parenteral antibiotics and by changing the catheter over a guidewire using the same venous insertion site. Cell Immunol, 1995 Apr 1, 161(2), 188 - 94 Heligmosomoides polygyrus adult worm homogenate superantigen: presentation to T cells requires MHC class I positive accessory cells; Robinson M et al.; A series of experiments were carried out to further characterize the previously discovered Heligmosomoides polygyrus, adult worm homogenate (AWH), superantigen . AWH, in contrast to staphylococcal enterotoxin B (SEB) superantigen, was totally unable to stimulate naive thymocytes, in either the presence or the absence of exogenous accessory cells (AC) . Experiments using AC from B10 congenic mice failed to indicate a requirement for a specific MHC haplotype for successful presentation of the AWH superantigen and also indicated that the presence or absence of the H-2,E molecule on AC did not affect AWH stimulation of T cell hybridomas . Furthermore, AWH was found to require the presence of MHC class I-positive AC in order to stimulate T cell hybridomas, while, in contrast, the absence of MHC Class II on AC did not affect the superantigenic properties of AWH . Initial characterization of the T cell hybridomas stimulated by the AWH superantigen, indicated that all were CD4-positive and that three of them expressed TCR V beta 8.1 . Hence AWH superantigen can stimulate TCR V beta 8.1/CD4-positive T cells only in the presence of MHC Class I-positive AC. Eur Heart J, 1995 Apr, 16 Suppl B, 94 - 8 Surgical treatment of infective endocarditis; Acar J et al.; Optimal timing of surgery in infective endocarditis (IE) depends mainly on the haemodynamic tolerance of the patient . Emergency surgery is required in cases of refractory heart failure due to valvular lesions, intracardiac fistulas and high grade cardiac conduction abnormalities caused by septal abscesses . Surgery must be considered in all patients who have undergone a transient episode of heart failure such as a pulmonary oedema and it must be early--within 2 or 3 weeks of starting antibiotic therapy in patients with aortic regurgitation . Bacteriological indications are less frequent: persistent sepsis beyond the first week in spite of medical therapy, mycotic IE or prosthetic valve endocarditis caused by Gram-negative or staphylococcal organisms . Some complications may swing the argument in favour of surgery: detection of root abscesses or mycotic aneurysms using transoesophageal echocardiography, and systemic embolisms with persistent, large and mobile vegetative lesions . Mortality rate depends on the haemodynamic status but also on the severity of anatomical lesions, on the type of endocarditis (native or prosthetic valve), on the type of surgery and on bacterial aetiologies . It varies between 5% and 30% . The late postoperative outcome is good . The actuarial survival rate at 8 years was 70% in our series of 31 patients with aortic regurgitation and early surgery . In mitral regurgitation, conservative surgery is possible in most cases . In our department, 48 patients with mitral bacterial lesions have been operated on with conservative surgery without operative mortality . IE was active in 14, recent in 12 and had occurred earlier in 22.(ABSTRACT TRUNCATED AT 250 WORDS) Eur Heart J, 1995 Apr, 16 Suppl B, 63 - 7 Echocardiographic assessment of prosthetic valve endocarditis; Vered Z et al.; Prosthetic valve endocarditis is still a very serious complication, carrying an incidence of death between 30 and 70% in some series . Therefore early and accurate diagnosis is crucial . Early (less than 60 days post surgery) endocarditis is usually a fulminant disease, where staphylococcal infection is most common . Late prosthetic endocarditis resembles more closely other forms of the disease . Conventional echocardiography is useful in the evaluation of prosthetic valve function, but it is very limited in the demonstration of infective lesions, primarily because of acoustic shadowing . Transoesophageal echocardiography (TE) enables high resolution imaging of the heart without chest wall interference, and viewing of the heart from the posterior (atrial, low pressure) side, where most of the vegetations are expected to be found in both mitral and tricuspid positions . It also enables better visualization of the left ventricular outflow tract, where aortic prosthetic vegetations tend to be present . Furthermore, transoesophageal echocardiography allows accurate diagnosis of some of the common complications of endocarditis: abscess/cavity formation; mycotic aneurysm; prosthetic valve dehiscence and regurgitation . In spite of these advantages, limitations should be recognized . Struts are commonly seen on transoesophageal echocardiography following surgery and should not be confused with vegetations . Similarly, normal prosthetic regurgitation should not be confused with paravalvar leakage . Nevertheless, transoesophageal echocardiography, when expertly used, changes the possibility for early and more accurate diagnosis of prosthetic valve endocarditis dramatically . Transoesophageal echocardiography should be included among the major criteria in the diagnosis and follow-up of prosthetic valve endocarditis. Eur Heart J, 1995 Apr, 16 Suppl B, 32 - 8 Early infective endocarditis on prosthetic valves; Chastre J et al.; Despite major advances in cardiovascular surgical techniques and routine use of prophylactic antimicrobial agents, prosthetic valve endocarditis (PVE) continues to complicate the course of a small percentage of patients after cardiac valve replacement . Using actuarial methods to describe the risk of PVE after valve implementation, several studies have shown that its incidence peaked at around 5 weeks and levelled off to a stable rate by 12 months, for a cumulative risk of 3% at that time . The microbial aetiology of early PVE is dominated by staphylococcal species, S . epidermis and S . aureus accounting for about 30% and 20% of cases, respectively, even though prophylactic regimens used today are targeted against these microorganisms . In nearly all patients, infection spread behind the site of attachment of the valve prosthesis, resulting in valve ring abscesses and valve dehiscence in 60% of cases . Valve obstruction by vegetations is much more uncommon except in patients with mitral or tricuspid valve endocarditis . The clinical course of early PVE tends to be frequently fulminant, with rapid deterioration of the haemodynamic status due to valvular or annular destruction or persistent bacteraemia . In some cases, however, the classic symptoms of endocarditis may be less noticeable because signs related to an initial source of bacteria, such as sternotomy wound infection, may be more prominent . While various non-invasive and invasive studies have been proposed to aid in the diagnosis of PVE, transoesophageal echocardiography is now the technique of choice for that purpose, as well as for detecting prosthetic valve dysfunction and other intracardiac complications of PVE.(ABSTRACT TRUNCATED AT 250 WORDS) Antibiot Khimioter, 1995 Apr, 40(4), 37 - 9 {Therapeutic effectiveness of furazolidone and difuracil (PAP-49) in experimental staphylococcal and Escherichia septicemia}; Terekhov VI et al.; The therapeutic efficacy of a new nitrofuran, N-(5-nitrofurilidene)-5-nitrofuran-2-(N'-acetyl)carboxamidra zone (difuracil or PAP-49) in experimental staphylococcal and Coli septicemia was stated and compared to that of furazolidone . It was shown in the models of staphylococcal and Coli septicemia of albino mice that by its therapeutic efficacy difuracil (PAP-49) was 1.3 times more active as furazolidone and by 1-2 days earlier eradicated the pathogens in the host. Eur J Clin Microbiol Infect Dis, 1995 Apr, 14(4), 359 - 62 Influence of the incubation atmosphere on the production of slime by Staphylococcus epidermidis; Perez-Giraldo C et al.; The influence of various incubation atmospheres on the growth and slime production of 23 Staphylococcus epidermidis strains was studied . The atmospheres evaluated were aerobiosis (control), anaerobiosis, candle jar, 5% CO2 and 10% CO2 . As compared to the aerobic control, growth was 55.7 +/- 19% (p < 0.01) in anaerobic incubation, 113.7 +/- 12% (p < 0.01) in 5% CO2, 112.8 +/- 13% (p < 0.01) in 10% CO2 and 106.4 +/- 7% (p > 0.1) in the candle jar . The slime production in relation to the aerobic control was 20.3 +/- 19% in anaerobiosis (p < 0.01), 22.3 +/- 27% (p < 0.01) in 5% CO2, 29.4 +/- 39% (p < 0.01) in 10% CO2 and 68.3 +/- 26% (p > 0.1) in the candle jar . The results of this study may explain the discrepancies which have been noted on occasion between slime formation data and pathogenicity. Eur J Clin Microbiol Infect Dis, 1995 Apr, 14(4), 342 - 6 Use of ribotyping to investigate tracheal colonisation by Staphylococcus epidermidis as a source of bacteremia in ventilated newborns; Betremieux P et al.; Ribotyping was used to determine whether a relationship exists between endotracheal tube colonisation with Staphylococcus epidermidis and bacteremia with this organism . Over a three-week period, four mechanically ventilated preterm babies presented with five episodes of infection and bacteremia . For each blood specimen obtained for culture a tracheal aspirate sample was collected at the same time by suctioning . After DNA extraction and cleavage by EcoRI, hybridisation was performed with a digoxigenin-labelled 16S-rDNA probe from Escherichia coli . Five different band patterns were recognised on the membrane . In two children the same band pattern was found in Staphylococcus epidermidis isolated from both blood and tracheal aspirate . Ribotyping thus could be used to differentiate a series of infections from an outbreak and showed that a relationship may exist between tracheal colonisation and bacteremia in mechanically ventilated newborns. Clin Orthop, 1995 Apr, (313), 214 - 9 Septic sacroiliitis; Osman AA et al.; The authors treated 31 patients with septic arthritis of the sacroiliac joint (14 patients with tuberculosis, 7 acute staphylococcal, 6 gonococcal, and 4 typhoid) . The clinical presentation was vague and nonspecific, but most patients reported buttock pain, low back pain and difficulty walking . In 28 patients, the diagnosis was established after clinical examination, bone scans, hematologic investigations, and blood cultures . The diagnosis was established through arthrocentesis of the sacroiliac joint in 9 patients . In 3 patients, there was a delay in diagnosis . Twenty-nine patients improved on a conservative regimen of bed rest and antibiotics . Two patients required open drainage because of a large buttock abscess that was secondary to tuberculosis sarcoiliitis. FEMS Immunol Med Microbiol, 1995 Apr, 11(2), 91 - 7 Staphylococcal enterotoxin B toxicity in BALB/c mice: effect on T-cells, plasma cytokine levels and biochemical markers; Wood AC et al.; Groups of BALB/c mice were treated with a sub-lethal dose (60 micrograms) of staphylococcal enterotoxin B (SEB) intraperitoneally and were sacrificed at 2, 5, 8, or 10 h post-injection . Organ, blood plasma and lymph node samples from these mice were analyzed . Plasma levels of urea, creatinine and alanine aminotransferase were significantly raised above normal by 5 h post-injection . However, alkaline phosphatase levels showed an erratic increase after toxin administration and, after administration of 10-40 microgramS SEB per mouse, were consistently at least 30% below normal levels at 24 h post-injection . Weight change was also monitored but found to be inconsistent . Lung, spleen and kidney samples appeared normal on histopathological examination, but liver samples showed minor polymorph infiltration and congestion . TNF-alpha, and IL-1 alpha levels in the plasma were raised by 8 h to picogram levels per ml of plasma, whereas IFN-gamma and IL-2 were raised by 2 h to nanogram levels per ml of plasma . Lymph node cells taken from mice treated with toxin were given a secondary stimulation with toxin in vitro . Although the response of the cells was lower than normal on assay at four days, a time response curve showed a peak in cell responsiveness to secondary stimulation with toxin at three days . These data indicate that biochemical markers and cytokine levels are affected by the administration of SEB to mice and may be used as indicators of toxicity. Histochem J, 1995 Apr, 27(4), 300 - 8 Binding of bacterial toxins to glycoproteins in the envelopes of rainbow trout eggs; Kudo S et al.; The ability of the vitelline and fertilization envelopes of rainbow trout eggs to trap toxins was investigated using cholera enterotoxin B and staphylococcal enterotoxin B in cytochemical or immunocytochemical experiments . Extracts from both envelopes were investigated by immunoblot analysis to identify toxin-binding proteins after SDS-PAGE . Binding studies of cholera enterotoxin B to vitelline envelopes and fertilization envelopes revealed a greater reactive intensity in the former . Treatment with neuraminidase enhanced the reactive intensity (or deposit) in the vitelline envelope and fertilization envelope outermost layers, with more conspicuous reactivity in the former . Cytochemical experiments showed that exogenous ganglioside GM1 considerably enhanced cholera enterotoxin B binding to vitelline and fertilization envelopes . This enhancement was shown by an intense reactivity following the occurrence of new binding sites on the vitelline envelope inner surface and the inner wall of the zona radiata, a simultaneous extreme reduction in the reactivity of the vitelline envelope outermost layer, and a striking increase in reactive products in the fertilization envelope outermost layer . The surface region of the vitelline or fertilization envelope outermost layer was the binding site for staphylococcal enterotoxin B, and neuraminidase treatment caused a considerable reduction of reactive products in these areas . Immunoblot analysis of cholera enterotoxin B- or staphylococcal enterotoxin B-binding substances in extracts from the vitelline envelopes or fertilization envelopes demonstrated that the great majority of the binding substances are glycoproteins . The present results suggest that glycoproteins constituting the vitelline envelope or fertilization envelope may contribute to the protection of the egg itself or the embryo by trapping noxious toxins. J Biomed Mater Res, 1995 Apr, 29(4), 485 - 93 Adhesion of Staphylococcus epidermidis to biomedical polymers: contributions of surface thermodynamics and hemodynamic shear conditions; Wang IW et al.; Adhesion studies of Staphylococcus epidermidis RP62A were conducted using a rotating disk system to determine the roles of surface physicochemistry and topographies under physiologic shear conditions . Six materials were investigated: biomedical reference polyethylene and polydimethylsiloxane; argon plasma-treated reference polyethylene (Ar-PE); Silastic; expanded polytetrafluoroethylene; and woven Dacron . All of the polymers except Dacron demonstrated reduced bacterial adhesion with increasing shear stress . Argon plasma treatment of polyethylene reduced the level of staphylococcal adhesion . Adsorption of human plasma proteins effected significantly lower numbers of adherent bacteria . The lowest adhesion was observed for Ar-PE in 1% human plasma protein solution, whereas Dacron had the highest number of adherent bacteria . The high adhesion on Dacron was attributed to increased bacterial flux caused by topography-induced turbulent flow and physical entrapment of the bacteria in the fiber interstices . The results indicate that the driving force for S . epidermidis adhesion is strongly influenced by substrate physicochemistry, but this may be dominated by physical forces such as shear and turbulence. J Biomed Mater Res, 1995 Apr, 29(4), 455 - 66 Bacteria/blood/material interactions . I . Injected and preseeded slime-forming Staphylococcus epidermidis in flowing blood with biomaterials; Brunstedt MR et al.; Blood-material interactions were studied using in vitro recirculation with human blood, slime-forming Staphylococcus epidermidis, and cardiovascular materials . Staphylococcus epidermidis, under preseeded or injected conditions, adhered to nonsmooth materials and elevated plasma levels of fibrinopeptide A (FpA) and C3a in the presence of all materials . Increased white blood cell (WBC) and platelet adhesion and thrombospondin and platelet factor 4 (PF4) release were noted for respective materials in the presence of injected bacteria . Materials that adhered significant quantities of injected S . epidermidis exhibited low levels of adsorbed proteins . Materials with high levels of preseeded S . epidermidis showed high levels of adsorbed proteins . Adhesion of preseeded bacteria and blood plasma elevations of C3a and FpA were lowest on semicrystalline polymer substrates, intermediate on halogenated substrates, and highest on amorphous substrates . In the presence of injected bacteria, WBCs and platelets adhered at earlier recirculation times to amorphous substrates than to semicrystalline substrates. Protein Sci, 1995 Apr, 4(4), 636 - 54 Proline cis-trans isomerization in staphylococcal nuclease: multi-substrate free energy perturbation calculations; Hodel A et al.; Staphylococcal nuclease A exists in two folded forms that differ in the isomerization state of the Lys 116-Pro 117 peptide bond . The dominant form (90% occupancy) adopts a cis peptide bond, which is observed in the crystal structure . NMR studies show that the relatively small difference in free energy between the cis and trans forms (delta Gcis-->trans approximately 1.2 kcal/mol) results from large and nearly compensating differences in enthalpy and entropy (delta Hcis-->trans approximately delta TScis-->trans approximately 10 kcal/mol) . There is evidence from X-ray crystal structures that the structural differences between the cis and the trans forms of nuclease are confined to the conformation of residues 112-117, a solvated protein loop . Here, we obtain a thermodynamic and structural description of the conformational equilibrium of this protein loop through an exhaustive conformational search that identified several substates followed by free energy simulations between the substrates . By partitioning the search into conformational substates, we overcame the multiple minima problem in this particular case and obtained precise and reproducible free energy values . The protein and water environment was implicitly modeled by appropriately chosen nonbonded terms between the explicitly treated loop and the rest of the protein . These simulations correctly predicted a small free energy difference between the cis and trans forms composed of larger, compensating differences in enthalpy and entropy . The structural predictions of these simulations were qualitatively consistent with known X-ray structures of nuclease variants and yield a model of the unknown minor trans conformation. Eur J Pediatr, 1995 Apr, 154(4), 295 - 8 Recombinant human interferon-gamma in patients with chronic granulomatous disease--European follow up study; Weening RS et al.; This was an uncontrolled, open-label follow up study of a previous 12-month, randomized, double-blind, placebo-controlled trial performed to assess the long-term efficacy and safety of Recombinant Human Interferon Gamma (rIFN-gamma) in patients with chronic granulomatous disease (CGD) . In two centres, 28 patients (24 male, 4 female) with a mean age of 16 years (range 3-37) entered the open-label phase . The patients were treated for a mean of 880 days (range 97-1375 days) . Visits were scheduled every 180 days and patients completed one to six visits . rIFN-gamma was administered subcutaneously three times weekly at a dose of 0.05 mg per m2 . During the open-label phase of the study 12 patients experienced a serious infection requiring hospitalization within 880 days . The median infection-free time was 993 days . No obvious increase of infections over time was seen . Phagocyte superoxide anion production and phagocyte staphylococcal killing were not influenced by therapy . Seven patients were withdrawn from the study, one because of an adverse reaction, three on their own wish and the other three because they changed to another trial . No patient died during the study . Conclusion . Treatment of patients with CGD with intracellular active antibiotics and additional interferon gamma as infection prophylaxis is safe and justified. Pediatr Res, 1995 Apr, 37(4 Pt 1), 455 - 9 Frequency and cytokine phenotype of blood T cells from premature infants responding to staphylococcal enterotoxin B; Hayward AR et al.; The responder cell frequency (RCF) of premature (< 1900 g birth weight) infants' blood lymphocytes, which proliferate in cultures stimulated by staphylococcal enterotoxin B, falls from 1:3400 to about 1:8000 during the first 2 wk of life . Term infants, in contrast, show no fall in RCF . The reduced RCF in the premature infants affected cells that make interferon-gamma more than cells making IL-4 . The reduced RCF was accompanied by a fall in the fraction of V beta 3+ T cells that entered cell cycle in stimulated cultures . The RCF of premature infants' T cells was increased in cultures supplemented with irradiated monocytes from adults . Addition of IL-4 (but not IL-2, IL-6, or indomethacin) increased the RCF and fraction of cells entering cell cycle of the premature infants . The data suggest that postnatal environmental factors limit the ability of premature infants' monocytes to support a T-cell response to staphylococcal enterotoxin B in vitro and that this limitation is overcome by adding IL-4. Diagn Microbiol Infect Dis, 1995 Apr, 21(4), 227 - 30 Reevaluations of disk diffusion susceptibility testing interpretive criteria for lomefloxacin and norfloxacin using fluoroquinolone-resistant isolates; Cormican MG et al.; The current National Committee for Clinical Laboratory Standards interpretive criteria for disk diffusion susceptibility testing of lomefloxacin and norfloxacin were reevaluated using a test panel of 298 bacteria (200 with ciprofloxacin minimum inhibitory concentrations (MICs) at > or = 4 micrograms/ml) . MICs were correlated with the diameter of zones of inhibition by regression statistics and error-rate bounding methods . Modifications of the interpretive criteria for lomefloxacin disk susceptibility testing are proposed as follows: susceptible at > or = 20 mm and resistant at < or = 16 mm, a 2-mm decrease of existing break-point zones . These criteria result in an absolute interpretive agreement of 95.3% with a very major (false susceptible) error rate of only 0.7% . The currently used criteria for norfloxacin (susceptible at > or = 16 mm and resistant at < or = 13 mm) were validated, and these break-points had an absolute interpretive correlation between methods of 91.9% . The change proposed for lomefloxacin disk interpretations would minimize minor and major errors most often reported for Staphylococcus saprophyticus isolates. Cell Immunol, 1995 Apr 1, 161(2), 158 - 65 Superantigens induce primary T cell responses to soluble autoantigens by a non-V beta-specific mechanism of bystander activation; Rott O et al.; Superantigens have been suggested to act as powerful TCR V beta-specific inducers of T cell reactivity in autoimmune diseases . We have investigated the capacity of staphylococcal enterotoxins (SE) to prime autoreactive T cell responses in naive animals in the Lewis rat model of experimental autoimmune encephalomyelitis (EAE), where myelin basic protein (MBP)-specific CD4+ effector T cells express almost exclusively V beta 8.2 TCR elements . By taking advantage of the reactivity of V beta 8.2+ MBP-specific T cells to SEE but not to other SEs in vitro, we estimated the potential of different SEs (SEA, SEB, and SEE) to induce a primary T cell response to soluble MBP in vivo . Upon immunization of naive rats with soluble MBP alone or MBP and SEB (which is only a very weak superantigen for rat T cells), no MBP-responses could be retrieved . Similarly, when coimmunizing naive rats with MBP and V beta 8.2-activating SEE, no autoreactivity was inducible . By contrast, coimmunization of animals with soluble MBP and the superantigen SEA that is strongly activating various T cell subpopulations in Lewis rats but not V beta 8.2+ (i.e., potentially MBP reactive) T cells led to a significant primary MBP-specific T cell autoreactivity . These SEA-induced MBP-reactive T cells expressed V beta 8.2 TCRs at levels similar to those seen in autoreactive T cells conventionally induced by immunization with MBP administered in complete Freund's adjuvant (CFA) and could induce disease in a transfer model of EAE . Thus, our results are consistent with the notion that superantigens are able to induce primary T cell responses to soluble autoantigens by a non-V beta specific mechanism of bystander priming. J Immunol, 1995 Apr 1, 154(7), 3204 - 12 Unique cytokine production profile of anergic human T cells in SCID-hu mice after staphylococcal enterotoxin B administration; Schols D et al.; Severe combined immunodeficient mice transplanted with human organs (SCID-hu mice), provide a unique in vivo model for studying human intrathymic T cell selection and development of tolerance . In vivo administration of staphylococcal enterotoxin B (SEB) to SCID-hu mice causes intrathymic clonal deletion of SEB-specific V beta+ T cells that occurs already at the immature CD4+8+ double positive stage . The expression of activation markers such as CD25, CD71, and HLA-DR was specifically increased on V beta+ T cells responding to SEB . The remaining SEB-specific human T cells that had not been deleted in vivo failed to proliferate when rechallenged with SEB in vitro . These SEB-specific T cells that were rendered anergic in vivo had a unique cytokine production profile . They failed to produce IL-2, which correlated with the lack of proliferation of these cells . In addition, they failed to produce TNF-alpha . However, the anergized T cells synthesized considerable amounts of IFN-gamma, granulocyte-macrophage CSF and IL-10 after SEB stimulation . This clonal anergy can be completely reversed in vitro by stimulating the SEB-specific cells in the presence of exogenous IL-2 or by triggering of the CD28/CTLA-4 activation pathway . Under these stimulation conditions, anergic T cells produced levels of IL-2 and TNF-alpha that were comparable to their non-anergized counterparts, whereas the levels of granulocyte-macrophage CSF, IL-10 and IFN-gamma production were even higher . Collectively, these data demonstrate that in vivo administration of SEB to SCID-hu mice leads to activation, deletion, and anergy of SEB-specific human thymocytes and that the production of IL-2 and TNF-alpha is selectively switched off in these anergic T cells. Riv Inferm, 1995 Apr-Jun, 14(2), 62 - 6 {Overview of nosocomial infections in a neonatal intensive care unit (1989-1993)}; Cologna M; Newborns admitted to any Intensive Care Unit (ICU) are more at risk for nosocomial infections . The author analyzed the incidence of nosocomial bacteriaemias occurred in the neonatal ICU of Trento, especially focusing on the relationship between weight at delivery, incidence of infections and mortality . The incidence of bacteriaemiae during the observation period (1.189-31.12.93) accounted for 3.5%, and 2.8% were classified as nosocomial . The most frequently involved organism was the Staphylococcus PCN (62% of bacteriaemiae) . High risk newborns weighted < 1500 g; 10.7% were affected by nosocomial bactaeriaemia, representing the 56.1% of all the observed bacteriaemiae . A strong association (p < 0.05) was also observed between bactaeriaemiae and mortality, in newborns weighting less than 1000 g . Since low and very low birth weigh infants are particularly at risk for infections, special attention should be paid to the invasive techniques and a systematic reporting and documentation of epidemiology of infections, in order to monitor impact of modifications in caring techniques is warranted. FEBS Lett, 1995 Mar 27, 362(1), 29 - 33 A cell-free protein translocation system prepared entirely from a gram-positive organism; Schimz KL et al.; A cell-free protein translocation system derived exclusively from a Gram-positive bacterium is described here for the first time . Highly efficient in vitro synthesis of plasmid encoded preprolipase of Staphylococcus hyicus is accomplished by coupled transcription/translation using either a cytosolic extract of S . carnosus alone or in combination with T7-RNA-polymerase . Addition of inside-out cytoplasmic membrane vesicles of S . carnosus leads to the partial conversion (processing) of preprolipase to prolipase . In addition, as shown in a protease protection assay, a significant part of preprolipase plus prolipase is translocated in vitro into the lumen of the vesicles . Translocation of preprolipase into the membrane vesicles requires the proton-motive force and the S . carnosus SecA protein. J Immunol, 1995 Mar 15, 154(6), 2600 - 11 Selective expansion followed by profound deletion of mature V beta 8.3+ T cells in vivo after exposure to the superantigenic lectin Urtica dioica agglutinin; Galelli A et al.; Urtica dioica agglutinin (UDA) is a superantigen that, in vitro, binds to specific carbohydrate structures on class II and induces a sixfold enrichment of V beta 8.3+ BALB/c mice splenic T cells . Superantigens have pleiotropic effects in vivo, causing the activation, proliferation, and deletion of specific T cells, but are heterogenous in regard to their effects on T cell tolerization . We, therefore, compared the responses of peripheral T cells from adult BALB/c mice with the i.v . injection of 50 micrograms UDA or the bacterial superantigen staphylococcal enterotoxin B (SEB) that also recognizes the V beta 8.3 gene product . The data presented indicate that activation, clonal expansion, anergy, and death of V beta 8.3+ T cells occur sequentially after UDA administration . Two days after UDA injection, the proportion of V beta 8.3+ T cells in the periphery is elevated to approximately twice that of normal mice . This expansion occurs in both CD4+ and CD8+ subsets . V beta 8.3+ T cells from UDA-primed mice are anergic to UDA restimulation and fail to proliferate or to produce IL-2 . Futhermore, the proliferation of V beta 8.3+ T cells is followed by their rapid disappearance concomitant with their specific elimination by apoptosis . In 1 wk, all CD4+ V beta 8.3+ peripheral T cells are deleted . The decline of V beta 8.3+ T cells in the CD4+ subset is more than in the CD8+ subset . This occurs in thymectomized and in thymus-intact animals . Two months after UDA priming, the percentage of V beta 8.3+ T cells is still lower than in control mice. J Med Microbiol, 1995 Mar, 42(3), 156 - 60 Chronic bacteraemia due to Staphylococcus epidermidis after bone marrow transplantation; Lina B et al.; A chronic bacteraemia due to Staphylococcus epidermidis occurred in a patient undergoing allogeneic bone marrow transplantation . Forty-two S . epidermidis isolates were obtained from blood cultures over a period of 5 months . Isolates were separated into three groups by SmaI macrorestriction characterisation with pulsed-field gel electrophoresis (PFE-1, one isolate; PFE-2, 32 isolates; PFE-3, nine isolates) . Differences were detected in antimicrobial susceptibility patterns among isolates belonging to group PFE-2 . The two strains, PFE-2 and PFE-3, were both responsible for the chronic bacteraemia and were isolated during different admissions to the hospital . A central venous catheter was the portal of entry for PFE-2 . DNA macro-restriction analysis with pulsed-field gel electrophoresis was helpful in the epidemiological investigation of this S . epidermidis chronic bacteraemia. J Leukoc Biol, 1995 Mar, 57(3), 450 - 4 Differential inhibitory effects of interleukin-10, interleukin-4, and dexamethasone on staphylococcal enterotoxin-induced cytokine production and T cell activation; Krakauer T; The cytokine profile of human peripheral blood mononuclear cells (PBMC) stimulated by staphylococcal enterotoxin (SE) A and B was examined . Production of tumor necrosis factor (TNF alpha), interleukin (IL)-1, IL-6, IL-2, and gamma interferon (IFN-gamma) was observed . In contrast, Th2 cytokines IL-4 and IL-10 were absent from SEA- or SEB-stimulated PBMC . Moreover, adding IL-10 to SE-stimulated PBMC inhibited the production of IL-1, IL-6, TNF alpha, and IFN gamma by 50 to 80% but had less effect (8-30%) on T cell proliferation . IL-4 was less effective than IL-10 in inhibiting cytokine production and enhanced T cell proliferation by SEA or SEB . The anti-inflammatory agent, dexamethasone, was the most potent agent in controlling the SE-mediated effects as evidenced by inhibited T cell proliferation (55%) and reduced levels of IL-1, IL-6, and IFN gamma (60% to 100%) and TNF alpha (50%) . Reducing levels of toxic mediators such as TNF alpha, IL-1, IL-6, and IFN gamma by dexamethasone in SE-induced T cell responses may be a useful therapeutic strategy to circumvent SE toxicity and pathogenesis. Clin Exp Immunol, 1995 Mar, 99(3), 398 - 403 Cytotoxic activity of V beta 8+ T cells in Crohn's disease: the role of bacterial superantigens; Baca-Estrada ME et al.; In Crohn's disease, disease-related stimuli could alter the T cell receptor (TCR) repertoire . To examine the possibility that changes in function may occur in T cell subsets without obvious changes in expression of TCR, we analysed the TCR repertoire of cytotoxic T lymphocytes in Crohn's disease peripheral blood . Furthermore, we examined the effect of bacterial superantigens, staphylococcal enterotoxin B (SEB) and E (SEE) on the cytotoxic function of T cell subsets bearing different TCR V genes using MoAbs specific for CD3 and TCR V gene products in a redirected cytotoxicity assay . There was no difference between patients and controls in the cytotoxicity measured in concanavalin A (Con A)-stimulated peripheral blood mononuclear cells (PBMC) with anti-CD3 or with six of seven anti-TCR V gene MoAbs . However, the cytotoxicity of V beta 8 T cells was decreased in Crohn's disease patients . This was not due to a decrease in total or CD8+ T cells expressing V beta 8 . Furthermore, in normal subjects, PBMC stimulation with SEE and SEB selectively expanded and increased the cytotoxicity of V beta 8 and V beta 12 T cells, respectively . In Crohn's disease, although SEB stimulation increased the number and cytolytic function of the V beta 12 subset, SEE stimulation failed to increase cytolytic activity of V beta 8+ T cells in spite of the expansion of V beta 8+ T cells . These results suggest that the changes in cytotoxic function observed in V beta 8 T cells in Crohn's patients may reflect previous exposure to a V beta 8-selective superantigen. Clin Exp Immunol, 1995 Mar, 99(3), 345 - 51 Synovial cells are potent antigen-presenting cells for superantigen, staphylococcal enterotoxin B (SEB); Origuchi T et al.; There is ample evidence suggesting that superantigens may act as a triggering factor in the pathogenesis of rheumatoid arthritis (RA) . We investigated whether superantigen could activate T cells in the presence of synovial cells . T cells were cultured with SEB in the presence of interferon-gamma (IFN-gamma)-treated synovial cells . T cell proliferation and activation were assessed by 3H-thymidine incorporation and IL-2 production . The expression of HLA class II antigens and adhesion molecules on synovial cells was detected by flow cytometer . In the presence of IFN-gamma-treated synovial cells, T cells proliferated vigorously and produced IL-2 in response to SEB . A low SEB-induced T cell response was noticed in the presence of untreated synovial cells . Allogeneic as well as autologous IFN-gamma-treated synovial cells markedly enhanced SEB-induced T cell proliferation . IFN-gamma-treated synovial cells had increased expression of HLA class II antigens and intercellular adhesion molecule-1 (ICAM-1) adhesion molecules . MoAbs towards these antigens markedly inhibited the SEB-induced T cell response . These results indicate that activated synovial cells are potent antigen-presenting cells for SEB to T cells, and that superantigens may play a critical role in the pathogenesis of RA through activated synovial cells. J Thorac Cardiovasc Surg, 1995 Mar, 109(3), 561 - 4 Effect of vancomycin infusion on cardiac function in patients scheduled for cardiac operation; Rosenberg JM et al.; Patients scheduled for cardiac operation often receive vancomycin before the operation to decrease postoperative staphylococcal wound infections . In animal studies, vancomycin depressed cardiac function approximately 15% . Because of the potentially serious consequences of myocardial depression in patients undergoing cardiac operation, we examined the effect of vancomycin infusion on cardiac hemodynamics in patients scheduled for cardiac operation . Patients who were scheduled for cardiac operation and vancomycin prophylaxis were enrolled in our study . After baseline cardiac output, mean arterial pressure, central venous pressure, and pulmonary capillary wedge pressure were measured, 1 gm of vancomycin HCl was infused over 1 hour . Cardiac output, mean arterial pressure, central venous pressure, and pulmonary capillary wedge pressure were measured at 15, 30, 60, 90, and 120 minutes after the start of the infusion . In the 46 patients that completed the study, no significant change was observed in cardiac output or systemic vascular resistance at any time when compared with baseline . Mean arterial pressure increased significantly (p = 0.03) between baseline (90.8 +/- 2.4 standard error of mean) and 90 minutes (94.1 +/- 2.4 standard error of mean) . One patient had a transient 30% fall in mean arterial pressure and systemic vascular resistance with facial flushing during the infusion . In conclusion, we found that vancomycin infusion over 1 hour in patients before cardiac operation is safe and not associated with cardiac depression. Cell Immunol, 1995 Mar, 161(1), 28 - 33 Patterns of interferon-gamma mRNA expression in toxic shock syndrome toxin-1 expanded V beta 11+ T lymphocytes; Zhao YX et al.; We have recently demonstrated that toxic shock syndrome toxin-1 (TSST-1), a staphylococcal exotoxin with superantigenic properties, is involved in the pathogenesis of septic arthritis . The aim of the current study was to characterize in detail the in vitro properties of TSST-1 with regard to T cell activation patterns . We demonstrate that TSST-1 preferentially expands murine V beta 11+ T lymphocytes and this expansion occurs equally well within CD4 and CD8 compartments . To analyze the functional properties of V beta 11+ T cells expanded in response to TSST-1, we have utilized a combined in situ hybridization and immunocytochemistry method . With this technique we show that TSST-1-stimulated V beta 11+ T cells are an important source of IFN gamma mRNA synthesis, suggesting that this cytokine may participate in superantigen-mediated septic arthritis. J Urol, 1995 Mar, 153(3 Pt 1), 659 - 61 Inflatable penile implant infection: predisposing factors and treatment suggestions; Wilson SK et al.; A retrospective review of 1,337 consecutive inflatable prosthesis implantations was done to detect predisposing factors for infection . Operations were performed by the same team during a 7-year period . Of the procedures 823 were primary implantations, while the remaining 514 were either revisions (mechanical failure, iatrogenic causes or patient dissatisfaction), salvage operations or removals for