Acta Microbiol Pol, 1992, 41(3-4), 145 - 50 Staphylococcal L-asparaginase: catabolic repression of synthesis; Rozalska M et al.; The regulation mechanism of production of staphylococcal L-asparaginase was investigated . The role of cAMP in regulation of its synthesis was confirmed . Production of L-asparaginase from S . aureus NCTC 4135 was inhibited by all carbon sources, mono- and disaccharides added to the growth medium . The strongest inhibition was caused by saccharose and maltose, whereas weaker by galactose, lactose, mannitol and mannose . It was found that exogenous cAMP in the presence of carbon sources stimulated synthesis of the investigated enzyme. Ann Trop Paediatr, 1992, 12(4), 451 - 3 Pyogenic liver abscess causing acute Budd-Chiari syndrome; Mehrotra G et al.; Acute Budd-Chiari syndrome caused by compression of the inferior vena cava by a space-occupying lesion in the liver is rare in children . We report a case where the compression was due to a large staphylococcal abscess in the right lobe of the liver . A high index of suspicion in such a case ensures early intervention and saves life. Microbios, 1992, 71(288-289), 203 - 15 Detection and purification of a potential precursor protein or a prohaemolysin produced by Staphylococcus haemolyticus; Sevigny G et al.; The haemolytic substance H7 produced by Staphylococcus haemolyticus is composed of three peptides out of 44 amino acid residues each having a structure resembling a signal peptide . The cytoplasmic fraction for the presence of a protein precursor containing this signal sequence was investigated . Specific rabbit IgGs to substance H7 were isolated by affinity chromatography on Sepharose-4B-H7 . These anti-H7 IgGs recognized mainly a 51 kD protein in the cytoplasmic fraction of S . haemolyticus from 2, 4, 6, 8, 10 and 23 h cultures . These results support the idea that the 51 kD protein could be either a prohaemolysin or else the precursor of a protein of unknown function with a signal sequence showing homology with the haemolytic peptides . After affinity chromatography on Sepharose-4B-anti-H7, the 51 kD protein was shown associated with an RNA-protein complex composed of four or five proteins and an RNA estimated at 300 nt . This complex could be associated with the machinery of protein secretion . The 51 kD protein was finally purified to homogeneity by HPLC on a Protein Pak DEAE-5PW column in the presence of 5 M urea. J Immunol, 1991 Dec 15, 147(12), 4082 - 5 A recombinant C-terminal fragment of staphylococcal enterotoxin A binds to human MHC class II products but does not activate T cells; Hedlund G et al.; Binding of staphylococcal enterotoxin A (SEA) to MHC class II encoded proteins is a prerequisite for its subsequent activation of a large fraction of T lymphocytes through interaction with variable segments of the TCR-beta chain . We cloned SEA in Escherichia coli and produced four recombinant fragments covering both the N- and C-terminal regions . These fragments were used to analyze the interaction between SEA and the human MHC class II products . A C-terminal fragment of SEA, representing amino acids 107-233 bound to HLA-DR and HLA-DP but did not activate T cells . The three other fragments (amino acids 1-125, 1-179 and 126-233) neither bound to MHC class II Ag nor activated T cells . SEA apparently bind to HLA-DR and HLA-DP through its C-terminal part, whereas T cell activation is dependent on additional parts of the protein. Biochem J, 1991 Dec 15, 280 ( Pt 3), 809 - 11 Identification by protein microsequencing of a proteinase-V8-cleavage site in a folding intermediate of chick muscle creatine kinase; Morris GE et al.; We have identified by protein microsequencing a glutamic acid residue (Glu-166) in a folding intermediate of chick muscle creatine kinase that is very sensitive to cleavage by staphylococcal proteinase V8 . Most other glutamic acid residues, including Glu-168, are already partly protected from proteolytic attack at this stage . After the final stages of protein refolding, when enzyme activity is recovered, Glu-166 is also resistant to proteolysis. J Long Term Eff Med Implants, 1992, 1(4), 321 - 8 The inhibition of bacterial adhesion to a tobramycin-impregnated polymethylmethacrylate substratum; Oga M et al.; Tobramycin sulfate powder (1.2 g) was mixed with Palacos polymethylmethacrylate (PMMA) bone cement (40 g) to produce 100 discs containing 5.9 mg tobramycin per disc . These discs were used to evaluate the inhibition of bacterial adhesion to an antibiotic-laden biomaterial . Tobramycin-impregnated PMMA discs and control discs containing no tobramycin were exposed in vitro to Staphylococcus epidermidis . Colonization was quantitated using plate count techniques and electron microscopy . Tobramycin-impregnated surfaces reduced adhesive bacteria colonization by 1 log relative to control discs . These observations suggest that tobramycin-impregnated PMMA may not be significantly effective in preventing colonization of the biomaterial substratum and PMMA may be a poor choice as a drug delivery vehicle in biomaterial and compromised tissue-centered infections. Eur J Biochem, 1991 Dec 5, 202(2), 421 - 9 Pericytes of the brain microvasculature express gamma-glutamyl transpeptidase; Frey A et al.; The expression of gamma-glutamyl transpeptidase (GGT) is a specific property of the brain capillary endothelium that constitutes the blood-brain barrier . We report here the detection of GGT, not only in endothelial cells, but also in pericytes, demonstrating that a brain capillary-specific pericyte population exists . We raised antibodies to GGT using a porcine brain microvessel GGT-protein-A (staphylococcal protein A) fusion protein as antigen which was expressed in Escherichia coli . The immunohistochemical analysis of the subcapillary distribution of GGT in porcine brain cortex and cerebellum sections by both light and electron microscopy revealed the expression of GGT in the capillary-adjacent pericytes in addition to the GGT-positive endothelial layer . We confirmed these data for cultured porcine brain microvascular endothelial cells and pericytes . GGT immunofluorescence could be detected in both cell types in culture . Endothelial cells exhibited a weak staining, whereas pericytes were strongly positive for GGT . Due to the high phagocytotic activity of pericytes and their location on the abluminal surface of the microvessels, we propose a possible protective or detoxifying function of GGT in cerebrovascular pericytes. Circulation, 1991 Dec, 84(6), 2539 - 46 Protection against endocarditis due to Staphylococcus epidermidis by immunization with capsular polysaccharide/adhesin; Takeda S et al.; BACKGROUND . Staphylococcus epidermidis is the principal pathogen in prosthetic valve endocarditis . The capsular polysaccharide adhesin (PS/A) has been shown to mediate attachment of bacteria to medical devices . In this study, we investigated the efficacy of active and passive immunization against PS/A in preventing S . epidermidis endocarditis in a rabbit model . METHODS AND RESULTS . Aortic valve vegetations were produced by inserting a Teflon catheter into the left ventricle through the right carotid artery . Bacteremia and endocarditis were then established by implanting in the left jugular vein a catheter that was attached to an osmotic pump and contaminated with S . epidermidis strain RP62A . During a 3-week study period, of 64 blood cultures taken every second or third day from six nonimmune rabbits, 54 (84%) yielded strain RP62A . In rabbits actively immunized with PS/A, eight of 60 blood cultures (13%) were positive (odds ratio 5.0, 95% CI, 2.0-12.3, p = 0.005) . At death, all six nonimmune rabbits had infected vegetations that yielded 10(6)-10(11) colony-forming units (cfu)/g of vegetation, whereas only one PS/A-immunized rabbit had an infected vegetation . Immunization protocols designed to elicit antibody to teichoic acid but not to PS/A afforded no protection against bacteremia or endocarditis . Infusion of monoclonal antibody to PS/A through a catheter in the right jugular vein provided a level of protection against both bacteremia and endocarditis comparable to that produced by active immunization . In vitro, antibody against PS/A was opsonic for S . epidermidis . CONCLUSIONS . Immunoprophylaxis targeted at staphylococcal PS/A is a promising new approach to the prevention of prosthetic valve endocarditis. J Immunol, 1991 Dec 1, 147(11), 3876 - 81 Staphylococcal toxins bind to different sites on HLA-DR; Chintagumpala MM et al.; Staphylococcal enterotoxins (SE) and toxic shock syndrome toxin 1 (TSST-1) bind to MHC class II molecules and the toxin-class II complexes induce proliferation of T cells bearing specific V beta sequences . We have previously reported that these toxins display varying binding affinities for HLA-DR1 . We now investigated whether these differences simply reflected differences in binding affinity for a single class II binding site or, at least in part, the engagement of different binding sites on the HLA-DR complex . Through competitive binding studies we show that SEB and TSST-1, which are not closely related by their amino acid sequences, bind to two different sites on HLA-DR . Both of these sites are also occupied by staphylococcal enterotoxin A (SEA), enterotoxin D (SED), and enterotoxin E (SEE) which exhibit more than 70% amino acid sequence homology . SEB and TSST-1 failed to inhibit SEA binding to HLA-DR . These studies suggest that there may be three distinct, although perhaps overlapping, binding sites on HLA-DR for these toxins . Further, although SED and SEE are similar to SEA in structure, and appear to bind the same sites on HLA-DR as SEA, they displayed significantly lower binding affinities . T cell proliferative responses to SED required a higher concentration of the toxin than SEA, probably reflecting its lower binding affinity . SEE, however, elicited T cell responses at very low concentrations, similar to SEA, despite its much lower binding affinity . Therefore, although the affinities of these toxins to MHC class II molecules appear to significantly influence the T cell responses, the effective recognition of the toxin-class II complex by the TCR may also contribute to such responses. Immunology, 1991 Dec, 74(4), 638 - 44 The stage of negative selection in tolerance induction in neonatal mice; Ando T et al.; In flow microfluorometry analysis of thymus and lymph node cells of C57BL/6(I-E-,Mlsb) mice rendered neonatally tolerant to (C57BL/6 x AKR/J)F1 (I-E+,Mlsb/a) lymphoid cells, both CD4+ and CD8+ cells showed a striking reduction in the number of V beta 6+ cells capable of recognizing Mlsa in the context of major histocompatibility complex (MHC) class II molecules, indicating that clonal deletion of V beta 6+ cells by Mlsa antigen occurs just at a stage of immature V beta 6lowCD4+CD8+ thymocytes . On the other hand, the number of V beta 11+ cells capable of recognizing I-E was markedly reduced in CD4+ cells, but CD8+ cells showed only partial (20%) reduction of such a population . The clonal deletion of V beta 11+ cells by I-E may begin at the transitional stage from V beta 11lowCD4+CD8+ to V beta 11highCD4+CD8- single-position cells, and V beta 11lowCD4+CD8+ cells differentiating to V beta 11highCD4-CD8+ cells seem to be resistant to clonal deletion . V beta 11+ T cells are also stimulated by staphylococcal enterotoxin A (SEA) irrespective of expression of CD4 or CD8 . Nearly all of both V beta 11+CD4+ and V beta 11+CD8+ lymph node T cells were deleted by the injection of SEA every other day from birth . In their thymi, both V beta 11+CD4+CD8- and V beta 11+CD4-CD8+ single-positive thymocytes were deleted, and the proportion of V beta 11low thymocytes was lower than that of normal mice . The clonal deletion of V beta 11+ T cells by SEA injection occurs at a stage of immature V beta 11lowCD4+CD8+ double-positive thymocytes, resulting in deletion of both V beta 11+CD4+ and V beta 11+CD8+ T cells. J Protein Chem, 1991 Dec, 10(6), 669 - 83 Biosynthetic antibody binding sites: development of a single-chain Fv model based on antidinitrophenol IgA myeloma MOPC 315; McCartney JE et al.; The functional antigen binding region of antidinitrophenol mouse IgA myeloma MOPC 315 has been produced as a single-chain Fv (sFv) protein in E . coli . Recombinant 315 proteins included sFv alone, a bifunctional fusion protein with amino-terminal fragment B (FB) of staphylococcal protein A, and a two-chain 315 Fv fragment . Successful refolding of the 315 sFv required formation of disulfide bonds while the polypeptide was in a denatured state, as previously observed for the parent Fv fragment . Affinity-purified recombinant 315 proteins showed full recovery of specific activity, with values for Ka,app of 1.5 to 2.2 x 10(6) M-1, equivalent to the parent 315 Fv fragment . As observed for natural 315 Fv, the sFv region of active FB-sFv315 fusion protein was resistant to pepsin treatment, whereas inactive protein was readily degraded . These experiments will allow the application of protein engineering to the 315 single-chain Fv; such studies can advance structure-function studies of antibody combining sites and lead to an improved understanding of single-chain Fv proteins. Rev Esp Fisiol, 1991 Dec, 47(4), 201 - 8 Influence of blood proteins in the in vitro adhesion of Staphylococcus epidermidis to teflon, polycarbonate, polyethylene and bovine pericardium; Carballo J et al.; The influence of human plasma proteins (fibrinogen, albumin and fibronectin) on the adherence of Staphylococcus epidermis to teflon, polyethylene, polycarbonate and bovine pericardium was studied in an in vitro quantitative assay by scintillation counting . Bacterial adhesion was generally reduced by the presence of protein during the adherence assay except in the case of bovine pericardium, in which adherence remained almost unaffected . The effect of these plasma proteins on bacterial surface properties resulted in strong increases of surface charge as measured by ion-exchange chromatography and with no effect on hydrophobicity, estimated as contact angles . Adherence was not found to be correlated with these two properties, suggesting that bacteria-surface interactions must not be simplified to the influence of interfacial forces. Eur J Clin Microbiol Infect Dis, 1991 Dec, 10(12), 1007 - 12 In vitro selection of resistance to vancomycin in bloodstream isolates of Staphylococcus haemolyticus and Staphylococcus epidermidis; Herwaldt L et al.; The purpose of the study was to determine whether vancomycin-resistant strains of Staphylococcus haemolyticus could be selected regardless of the initial MIC of vancomycin . Twenty-one bloodstream isolates of Staphylococcus haemolyticus were studied by broth and agar selection methods . The broth method selected strains for which MICs of vancomycin ranged from 4 to 32 micrograms/ml and MBCs from 16 to greater than 128 micrograms/ml . The agar method selected strains for which MICs ranged from 8 to 32 micrograms/ml and MBCs from 8 to greater than 128 micrograms/ml . For comparison, seven strains of Staphylococcus epidermidis were evaluated by the agar selection method . Final MICs of vancomycin ranged from 8 to 16 micrograms/ml; MBCs ranged from 16 to 64 micrograms/ml . Clearly, in vitro exposure to vancomycin can select strains of Staphylococcus haemolyticus and Staphylococcus epidermidis for which MIC values are beyond the susceptible breakpoint. J Rheumatol, 1991 Dec, 18(12), 1841 - 4 A prospective analysis of patients with rheumatic diseases attending referral hospitals in Harare, Zimbabwe; Stein CM et al.; In a 10-month prospective study a research assistant identified 411 patients with rheumatic disease at the 2 referral hospitals in Harare . Rheumatic disease accounted for less than 1% of hospital admissions . Rheumatoid arthritis, the commonest condition, accounted for 18% of patients, many of whom had impaired functional capacity . Septic arthritis (16%) was common in younger patients, often affecting the hip or knee and often associated with other complications of disseminated staphylococcal infection . Osteoarthritis (9%), rheumatic fever (7%), gout (6%), human immunodeficiency virus associated musculoskeletal problems (6%) and systemic lupus erythematosus (5%) were relatively common while the spondyloarthropathies occurred less frequently . The spectrum of rheumatic disease seen in teaching hospitals in Harare, although significantly different from that seen in Europe and North America, approximates the pattern seen in developed countries more closely than previous studies from Africa would suggest. Int J Food Microbiol, 1991 Dec, 14(3-4), 325 - 31 Feasibility of a reference material for staphylococcal enterotoxin A; Notermans S et al.; A reference material for staphylococcal enterotoxin A (SEA), was produced by spray-drying the toxin in milk . With this procedure the SEA was distributed homogeneously in the material . For ease of handling the reference material was encased in gelatin capsules, each containing 405 ng of SEA . Simply dissolving the milk powder in distilled water resulted in a 100% recovery of the SEA present . The reference material would appear suitable for testing laboratory performance, comparison of detection methods and to validation of extraction procedures. Int J Food Microbiol, 1991 Dec, 14(3-4), 305 - 12 Comparison of four kits for the detection of staphylococcal enterotoxin in foods from outbreaks of food poisoning; Wieneke AA; Four commercial kits, three based on sandwich ELISA techniques and one on latex agglutination were compared for the detection of staphylococcal enterotoxins in foods from outbreaks of food poisoning . Enterotoxin was detected in 14 of 18 foods with the Swiss SET-EIA and in 9 or 10 with the Unipath SET-RPLA and two ELISAs from Transia . The advantages and disadvantages of the four methods are discussed. Zentralbl Bakteriol, 1991 Dec, 276(1), 86 - 93 Staphylococcal lipoteichoic acid exerts growth factor-like activity towards human and murine cells; Ohshima Y et al.; Lipoteichoic acid (LTA) was extracted from Staphylococcus saprophyticus strain S1 and tested for the capacity to induce hematopoietic and lymphatic cell proliferation . As compared to nontreated cells, the number of human bone marrow cells significantly increased in the presence of low LTA concentrations . Optimal growth was observed on the fifth day of in vitro incubation . After exposure to LTA, the lymphocyte proliferation rate also increased in a dose and time dependent manner . On the other hand, human epithelial cells and fibroblasts did not show enhanced growth activities in the presence of LTA. Zentralbl Bakteriol, 1991 Dec, 276(1), 36 - 45 Evidence for degradation of synthetic polyurethanes by Staphylococcus epidermidis; Jansen B et al.; The survival of Staphylococcus epidermidis strain KH 11 in the presence of synthetic high molecular polyurethanes was prolonged in comparison to control experiments performed in the absence of any nutrients . Investigations of the bacteria after contact with the polymers revealed changes in their surface properties and metabolism, in particular a marked induction of urease activity . ESCA (Electron Spectroscopy for Chemical Analysis) measurements detected a decrease in elementary nitrogen in the polyurethane surfaces after incubation with the bacteria . The alterations observed indicate an urease-induced degradation of synthetic polymers by Staphylococcus epidermidis KH 11. Zh Mikrobiol Epidemiol Immunobiol, 1991 Dec, (12), 42 - 5 {The reactogenicity and efficacy of a dried cell-free staphylococcal vaccine in treating chronic bronchitis}; Egorova NB et al.; The data obtained in the controlled trial of the immunotherapy of chronic bronchitis (CB) patients with lyophilized acellular staphylococcal vaccine developed at the Mechnikov Research Institute for Vaccines and Sera (USSR Acad . Med . Sci.), Moscow, are presented . The patients were divided at random into two groups; of these, one group received the vaccine and the other, placebo (0.9% sodium chloride solution) . The preparations were injected subcutaneously simultaneously with traditional treatment . The vaccine was well tolerated by the patients . In the blood of the patients receiving the vaccine, in contrast to those receiving placebo, a significant increase in the level of specific antibodies determined in the passive hemagglutination test and IgG was noted . When following the remote consequences of the disease for a year after the course of immunotherapy, a significant decrease in the occurrence of aggravations, an increase in the duration of remission and a decrease in the duration of sick leaves were registered . These data indicate that the immunotherapy of CB with lyophilized acellular staphylococcal vaccine is a promising method of preventing relapses. Klin Med (Mosk), 1991 Dec, 69(12), 53 - 5 {Evaluation of diagnostic indices of reactivity during treatment of patients with chronic bronchitis and bronchiectatic disease}; Linevskii IuV et al.; Evaluation of neutrophils conditions by glycogen, enzymatic activity (acid and alkaline phosphatases, peroxidase), lymphocyte blast-transformation reaction stimulated by staphylococcal antigen in 113 patients with bronchial pathology on treatment suggested the conclusion of their value in verification of the disease course correction of on-going treatment and definition of its effect . The methods acquire additional significance in objective assessment of the process activity in obscure clinical manifestations and lack of laboratory evidence for aggravation. Br J Ophthalmol, 1991 Dec, 75(12), 710 - 2 Posterior lens capsule abscess due to Propionibacterium acnes and Staphylococcus epidermidis following extracapsular cataract extraction; Manners RM et al.; A case of posterior lens capsular abscess occurring many months after an extracapsular cataract extraction is presented . This was caused by a mixed infection involving Propionibacterium acnes and Staphylococcus epidermidis . The significance of Staph epidermidis after such a long postoperative period is uncertain, but the case shows features typical of secondary endophthalmitis due to P acnes, including a long delay in onset and a grumbling course not brought under control by medical treatment . It supports the theory that the nidus of infection is localised in the posterior lens capsule by showing development of a visible capsular abscess with associated vitreous involvement . The subsequent removal of the capsule and vitreous, despite leaving the intraocular lens in place, led to complete resolution of the inflammation . Both organisms have previously been found to be sequestered in the posterior lens capsule by histological and microbiological examination of excised capsular specimens . It is important to consider them as possible causative agents in the formation of a postoperative capsular abscess. Kidney Int, 1991 Dec, 40(6), 1160 - 5 Simultaneous catheter replacement and removal in refractory peritoneal dialysis infections; Swartz R et al.; The present report describes more than nine years of experience with simultaneous removal and replacement of the chronic peritoneal dialysis (PD) catheter in treating refractory mechanical and infectious complications . Simultaneous catheter replacement and removal not only succeeded in 22 of 23 cases with non-infectious mechanical complications, allowing uninterrupted PD in all but three, but also succeeded in 30 (83%) of 36 additional cases with persisting or recurring infection . Simultaneous procedures failed in six (17%) of 36 infectious cases, due to persistent infection in two cases and to procedure complications in four cases . The clinical characteristics of the 30 successful infectious cases were compared to the characteristics of both the six failures, as well as 29 additional infectious cases in which the peritoneal catheter was removed but was not replaced because of a variety of serious complications (such as pancreatitis, abscess, sepsis, or fluid overload) . At the time of simultaneous catheter replacement in successful cases, temporary control of active peritoneal inflammation was achieved more frequently (80% vs . 31%, P less than 0.001) with a shorter interval of antibiotic coverage (6.4 +/- 0.9 vs . 14.7 +/- 1.3 days, P less than 0.001) . In addition, the successful cases were characterized by significantly more Staphylococcal infections (70% vs . 26%, P less than 0.001) and significantly fewer Pseudomonal or fungal infections (6% vs . 59%, P less than 0.001), although successful cases included some non-Pseudomonal, non-enteric gram negative infections (23%).(ABSTRACT TRUNCATED AT 250 WORDS) Eur J Vasc Surg, 1991 Dec, 5(6), 627 - 32 The clinical use of an antibiotic-bonded graft; Strachan CJ et al.; Attempts to produce an antibiotic-bonded prosthesis have failed owing to poor binding, drug toxicity or inadequate antimicrobial activity of the antibiotic particularly against Staphylococcus epidermidis . Rifampicin, with an ideal spectrum, but untested against slime-forming S . epidermidis has recently been shown to bind with carboxyl groups on gelatin-sealed Dacron . We therefore investigated rifampicin activity against 30 slime-forming adherent S . epidermidis colonies, isolated from 40 consecutive aortic graft recipients, and compared it with their methicillin, gentamicin, cefuroxime, tetracycline and vancomycin resistance patterns . The S . epidermidis colonies were highly sensitive to very low levels of rifampicin . Rifampicin was then bonded to gelatin-sealed Dacron aortic prostheses which were inserted in four patients at high risk of developing subsequent infection. Br J Rheumatol, 1991 Dec, 30(6), 464 - 7 A preliminary study of magnetic resonance relaxation times (T1 and T2) in inflammatory and degenerative synovial fluids; Bellamy N et al.; Multiple synovial fluid samples from 21 patients were analysed using standard synovial analysis techniques and by nuclear magnetic resonance spectroscopy . Significant negative correlations were noted between both T1 (P less than 0.01) and T2 (P less than 0.0006) relaxation times and synovial fluid total protein . No differences in T1 or T2 relaxation times were noted in synovial fluid between 16 patients with inflammatory forms of arthritis and five patients with degenerative arthritis . In a single rheumatoid arthritis patient with concurrent staphylococcal arthritis, T1 and T2 relaxation times did not vary between the active phase and the recovery phase . The lack of any significant differences in the measured relaxation times as a function of joint condition suggest that in vivo magnetic resonance measurements of T1 or T2 for joint analysis may not reveal information of either a diagnostic or pathophysiological nature. J Exp Med, 1991 Dec 1, 174(6), 1431 - 7 Reduction of lupus nephritis in MRL/lpr mice by a bacterial superantigen treatment; Kim C et al.; The effects of biweekly intravenous injections of Staphylococcus Enterotoxin B (SEB) into autoimmune MRL-lpr/lpr (MRL/lpr) mice were investigated . Rather than causing the expansion of V beta 8+ T cells, SEB administration resulted in the reduction V beta 8+, CD4-CD8- "double-negative" (DN) T cells . This was shown by FACS analysis as this putative pathogenic population was diminished in both spleen and lymph node . The symptoms of systemic lupus erythematosus (SLE) in MRL/lpr, which include high titers of anti-DNA antibodies and circulating immune complexes and proteinuria, were reduced in SEB-treated mice in a dose-dependent manner . The clinical parameters of SLE in MRL/lpr, which include lymph node hyperplasia and necrotic vasculitis, were suppressed in 50-micrograms SEB-treated mice . T cells bearing V beta 6 T cell receptor, which does not interact with SEB, were not reduced with SEB administration . Thus, disease suppression was associated with a specific reduction in the number of V beta 8+, DN T cells . These results implicate a possible therapeutic role of superantigen-based immunotherapy in V beta-restricted, T cell-dominated clinical syndromes. J Lab Clin Med, 1991 Dec, 118(6), 570 - 5 The primary structure of serum amyloid A protein in the rabbit: comparison with serum amyloid A proteins in other species; Liepnieks JJ et al.; Rabbit serum amyloid A (SAA) protein was isolated from acute-phase serum by ultracentrifugation, molecular seive chromatography, and ion-exchange chromatography . The complete amino acid sequence of the protein was established by sequence analysis of peptides derived from trypsin and Staphylococcus proteinase digestion of the protein . The molecule consisted of 104 amino acids and had an amino terminus that was blocked by pyrrolidonecarboxylic acid . Heterogeneity was not observed at any residue, which suggests that the material sequenced consisted of a single serum amyloid A species . The protein is highly homologous to serum amyloid A from humans and other animals, particularly in the middle portion of the molecule (positions 33 to 63), which suggests that this region may be important in its function . This highly conserved region may also contain the determinants for amyloid formation. J Perinatol, 1991 Dec, 11(4), 319 - 25 Acute phase reactants in neonatal bacterial infection; Pourcyrous M et al.; The C-reactive protein (CRP) level was evaluated in 142 infants requiring investigation for suspected infection . After excluding two neonates because of incomplete data, there remained 140 neonates, of whom 16 had septicemia . Fifteen of 16 had increased CRP levels . The CRP value was not elevated in any baby (n = 5) who had positive blood cultures for Staphylococcus epidermidis, all of whom had an uneventful clinical course . The CRP level was elevated in all six babies with meconium-aspiration syndrome, but was normal in five infants whose viral cultures were positive . Ninety-nine percent of uninfected babies had normal CRP values . Overall, CRP was a valuable test for diagnostic confirmation of bacterial infection . Elevated CRP level was always accompanied by at least one abnormality in the other tests performed . Although the study was not intended to predict clinical onset of bacterial disease, our results suggest that the CRP level, because of a high negative predictive value, may be useful in ruling out bacterial infection. J Clin Microbiol, 1991 Dec, 29(12), 2768 - 73 Molecular relatedness of Staphylococcus epidermidis isolates obtained during a platelet transfusion-associated episode of sepsis; Shayegani M et al.; Staphylococcus epidermidis was isolated from the blood of a 25-year-old pregnant woman following the administration of eight units of platelets . She had developed chills and a fever of 41.4 degrees C soon after the transfusions were completed . S . epidermidis was also obtained from all eight platelet units, as well as from the packed-erythrocyte unit associated with the first unit of platelets . The isolation of the same organism from these epidemiologically related sources provided us with the opportunity to phenotypically and genetically characterize the isolates . Several typing methods, including four molecular techniques, were used to increase our chances of finding any differences between the isolates under investigation . Phenotypic analyses demonstrated that S . epidermidis isolates from the patient, platelet units, and erythrocyte unit reacted in exactly the same manner in 15 biochemical tests, exhibited slime production, and had the same antibiotic susceptibility pattern . Genetic analyses, which included plasmid profiles, plasmid cross-hybridization, field inversion gel electrophoresis, and ribotyping, substantiated the relationships between the S . epidermidis isolates from the patient, platelet units, and erythrocyte unit . Eight S . epidermidis control strains unrelated to the case were found to differ significantly from the platelet-related strain. J Biol Chem, 1991 Nov 25, 266(33), 22569 - 81 The beta-glucan synthase from Lolium multiflorum . Detergent solubilization, purification using monoclonal antibodies, and photoaffinity labeling with a novel photoreactive pyrimidine analogue of uridine 5'-diphosphoglucose; Meikle PJ et al.; The membrane-bound beta-glucan synthase from Italian ryegrass (Lolium multiflorum L.) endosperm cells has been solubilized by both non-ionic and zwitterionic detergents . A complex relationship exists between the ratio of (1----3)-, (1----4)-, and (1----3, 1----4)-beta-glucan products of the solubilized enzyme, the cations present, and the concentration of the uridine 5'-diphosphoglucose substrate . Monoclonal antibodies directed against the beta-glucan synthase complex were generated by immunization of mice with an unfractionated microsomal reparation . Hybridoma cell lines were screened using a combination of indirect enzyme-linked immunosorbent assay followed by an enzyme-capture assay . The purified monoclonal antibodies were used with Pan-sorbin (stablized protein A-bearing staphylococcal cells) to immunoprecipitate an active beta-glucan synthase complex which had been solubilized from a microsomal preparation with 0.6% CHAPS . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the immunoprecipitated synthase complex revealed four major polypeptides of apparent molecular mass 30, 31, 54, and 58 kDa together with several minor components . The immunoprecipitated beta-glucan synthase complex was capable of synthesizing both (1----3)- and (1----4)-beta-glucans . A new photoreactive pyrimidine analogue of uridine 5'-diphosphoglucose, 5-{3-(p-azidosalicylamide}allyl-uridine 5'-diphosphoglucose was synthesized in a three-step reaction sequence involving mercuration of UDP-Glc, alkylation of 5-Hg-UDP-Glc, and acylation of 5-(3-amino)allyl-UDP-Glc and characterized by chemical and spectroscopic analysis . The analogue inhibits (Kiapp 16 microM) and, upon UV irradiation, irreversibly inactivates the beta-glucan synthase . The analogue was iodinated with Na125I to give a radiolabeled, photoreactive compound, and was used in photoaffinity labeling of UDP-Glc pyrophosphorylase, UDP-Glc dehydrogenase, and several putative UDP-Glc-binding proteins from L . multiforum . The radiolabeled analogue specifically labeled the 31-kDa polypeptide in the immunoprecipitated synthase complex . The photolabeling of this polypeptide is strictly dependent on UV irradiation, is blocked by uridine 5'-diphosphoglucose and uridine 5'-diphosphate, and reaches saturation at analogue concentrations above 300 microM . These results indicate that the 31-kDa polypeptide in the beta-glucan synthase complex bears a uridine 5'-diphosphoglucose-binding site and is involved in the catalysis of beta-glucan synthesis. J Immunol Methods, 1991 Nov 22, 144(2), 197 - 202 Detection of staphylococcal enterotoxin and toxic shock syndrome toxin-1 (TSST-1) by immunoblot combined with a semiautomated electrophoresis system; Orden JA et al.; An immunoblot technique combined with a semi-automated electrophoresis system has been developed for the detection of staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1) . The advantages of this method over other detection techniques include speed, sensitivity (10 ng/ml) and specificity . The use of semiautomated electrophoresis permits the routine detection of staphylococcal enterotoxins and TSST-1. Proc Natl Acad Sci U S A, 1991 Nov 15, 88(22), 9954 - 8 Identification of the staphylococcal enterotoxin A superantigen binding site in the beta 1 domain of the human histocompatibility antigen HLA-DR; Herman A et al.; The staphylococcal enterotoxin A (SEA) is a superantigen that must bind to class II molecules of the major histocompatibility complex to be recognized by T cells . In humans, most HLA-DR class II allelic and isotypic forms, such as DR1, bind SEA well . DRw53 is an exception, binding SEA very poorly . We have localized this difference to a single residue (amino acid 81) in the beta 1 domain . A highly conserved histidine at residue 81 allows SEA binding, but a tyrosine does not . Residue 81 is predicted to lie in an alpha-helix on the surface of the molecule, with its side chain pointing up out of the pocket associated with binding of conventional peptide antigens . This finding supports the hypothesis that superantigens and conventional antigens bind to different sites on the class II molecule. FEMS Microbiol Lett, 1991 Nov 15, 68(2), 143 - 9 Suppression of an Escherichia coli secA(ts) mutant by a gene cloned from Staphylococcus carnosus; Overhoff-Freundlieb B et al.; Escherichia coli mutant MM52 (secA(ts)) was transformed with a cosmid library from Staphylococcus carnosus, and a recombinant cosmid (pBO23) allowing growth at the non-permissive temperature (42 degrees C) was isolated . pBO23 also restored the growth defects of E . coli mutants IQ85 (secY(ts)) and IT41 (lep(ts)) . Nucleotide sequencing revealed that the DNA fragment responsible for the suppression effect codes for a S . carnosus protein highly homologous to the ribosomal protein L13 of E . coli . The staphylococcal L13 protein was efficiently incorporated into E . coli ribosomes . Possible explanations for the effect of this polypeptide on the growth of temperature-sensitive E . coli secretion mutants are discussed. Proc Natl Acad Sci U S A, 1991 Nov 15, 88(22), 10267 - 71 Profound alteration in an alpha beta T-cell antigen receptor repertoire due to polymorphism in the first complementarity-determining region of the beta chain; Gahm SJ et al.; Amino acid residues that are critical in maintaining the framework structure of immunoglobulin heavy- and light-chain variable (V) regions are strongly conserved in the V alpha and V beta proteins of the alpha beta T-cell antigen receptor (TCR alpha beta) . Consequently, it has been proposed that TCR alpha beta has a conformation similar to that of an immunoglobulin Fab fragment and that the regions of the TCR homologous to the three immunoglobulin complementarity-determining regions (CDRs 1, 2, and 3) bind to the peptide antigen-major histocompatibility complex (MHC) molecule ligand . A single amino acid substitution in the predicted CDR1 of the V beta 3 protein of certain mouse strains dramatically altered TCR alpha beta usage in an antigen-specific MHC-restricted immune response but did not abrogate V beta 3 specificity for the superantigens minor lymphocyte stimulatory locus (Mls)c and staphylococcal enterotoxin A (SEA) . The results confirm the importance of the V beta CDR1 in antigen-MHC molecule recognition, supporting the Fab-like structural model of TCR alpha beta, and provide further evidence that conventional antigen-MHC recognition and superantigen recognition are mediated by distinct regions of the TCR beta chain . They also suggest that allelic polymorphism may be a significant source of diversity in the TCR repertoire. J Immunol, 1991 Nov 15, 147(10), 3274 - 81 Mutation of the disulfide loop in staphylococcal enterotoxin A . Consequences for T cell recognition; Grossman D et al.; The hallmark of T cell responses to staphylococcal enterotoxins (SE) and other super-Ag is a selective stimulation of cells expressing particular TCR-V beta segments . Our previous studies suggested that the disulfide loop in SE is critical for their interaction with the TCR . To investigate this concept in further detail we constructed disulfide loop mutants of staphylococcal enterotoxin A (SEA), and examined these altered toxins for mitogenicity, class II MHC binding, and V beta specificity . We found that substitutions of either Cys-96 or Cys-106 decreased mitogenicity by 100-fold without significantly affecting class II binding or resistance of the molecule to proteolysis . Several mutants lost the capacity to stimulate V beta 11+ cells, except a Cys-106----Gln mutant for which V beta 11-stimulatory activity was increased . By contrast, mutants containing Cys----Ala substitutions acquired the capacity to stimulate V beta 6+ cells . Despite these effects of V beta specificity, all mutants retained the predominant preference of SEA for V beta 3+ cells . Neither exchange of regions flanking the loop in SEA with corresponding residues in SEB, nor conversion of the entire loop region of SEA to that of SEE, were associated with transfers of V beta specificity . Our results suggest that the disulfide loop in SEA contributes to toxin avidity for the TCR, rather than specificity for particular V beta. J Immunol, 1991 Nov 15, 147(10), 3296 - 302 Pertussis toxin prevents the induction of peripheral T cell anergy and enhances the T cell response to an encephalitogenic peptide of myelin basic protein; Kamradt T et al.; In a murine model of T cell-mediated autoimmune disease, experimental autoimmune encephalitis (EAE), 80% of all encephalitogenic T cell clones in H-2u mice use the V beta 8.2 TCR element . To induce EAE in susceptible strains of mice either heat-killed Bordetella pertussis organisms or Bordetella pertussis toxin (PT) must be injected in addition to Ag in CFA . We investigated the mechanisms by which PT facilitates the induction of EAE . Our data show, that PT interferes with the induction of Ag-induced peripheral T cell anergy . Furthermore it has a specific adjuvanticity for the autoantigen pAc1-11 in vivo and acts as a selective mitogen in vitro . We also tested the hypothesis that PT is a bacterial superantigen that specifically expands the V beta 8.2+ subset of T cells, thereby expanding the encephalitogenic T cell clones that are contained in this subset, so that the number of autoreactive T cells is brought over a critical threshold, necessary to induce autoimmune disease . Our data show that PT is not a superantigen . Staphylococcal enterotoxin B, a V beta 8.2-specific superantigen, does not enhance the immune response to the encephalitogenic peptide. Am J Respir Cell Mol Biol, 1991 Nov, 5(5), 411 - 5 Human alveolar macrophages inhibit receptor-mediated increases in intracellular calcium concentration in lymphocytes; Yarbrough WC Jr et al.; Prior studies have demonstrated that human alveolar macrophages (AM) are suppressive of lymphocyte function, through the mechanism of inhibition is unclear . In the current study, human AM inhibited receptor-mediated increases in intracellular calcium concentration ({Ca2+}i) in T cells, natural killer cells, and B cells . This effect was produced by either live or fixed AM, while peripheral blood monocytes caused a minimal reduction in {Ca2+}i . The inhibitory effect of AM was seen following 1 to 2 h of incubation with lymphocytes, was complete at 16 h, and did not affect ionomycin-mediated {Ca2+}i . Inhibition of {Ca2+}i by AM correlated with suppression of T-lymphocyte proliferation and cytotoxic T-lymphocyte activity in response to alloantigen and Staphylococcus A-induced immunoglobulin production . Our findings suggest that a membrane signal on AM is capable of inhibiting receptor-mediated signal transduction in lymphocytes and that this is likely a major mechanism by which immune responses are downregulated in the alveolus. Anesthesiology, 1991 Nov, 75(5), 893 - 5 Drug contamination from opening glass ampules; Zacher AN et al.; Recently there have been several reports of postoperative sepsis due to the intravenous injection of contaminated solutions of propofol (Diprivan) . The mechanism by which this contamination occurred has not been identified . This study sought to determine whether bacterial contamination of the contents of glass ampules can be decreased by swabbing the neck of the vial with alcohol prior to opening . Glass ampules of 1% propofol and 1% lidocaine were swabbed with a solution of Staphylococcus epidermidis . Half of these ampules were subsequently wiped with alcohol pads prior to being opened . An aliquot from each ampule was pipetted into a nutrient broth and allowed to incubate overnight at 37 degrees C . These solutions were plated on agar, incubated for 24 h, and then examined for bacterial growth . Three of the eight lidocaine ampules and six of the eight propofol ampules not cleaned with alcohol demonstrated evidence of bacterial contamination . The contents of all ampules that had been wiped with alcohol prior to being opened remained sterile (P less than 0.001 vs . non-alcohol-treated group for propofol ampules and P = 0.20 vs . non-alcohol-treated group for lidocaine ampules) . These data suggest that bacterial contamination of propofol and lidocaine may occur as a result of opening glass ampules . Wiping the outside of the ampule with alcohol immediately prior to opening may decrease this risk. South Med J, 1991 Nov, 84(11), 1375 - 7 Echocardiographic diagnosis of effusive-constrictive pericarditis due to staphylococcal pericarditis after cardiac surgery; D'Cruz IA et al.; Two weeks after coronary artery bypass surgery, a 43-year-old man was readmitted with fever, pneumonia, left pleural effusion, and pericarditis . Echocardiography showed a localized posterior pericardial effusion, pericardial thickening, and bulging of the ventricular septum toward the left ventricle . Right-sided catheterization indicated pericardial constriction . Effusive-constrictive pericarditis was confirmed at surgery . Cardiac imaging played an important role in diagnosis of this unusual complication of cardiac surgery. Infect Immun, 1991 Nov, 59(11), 4049 - 55 Murine macrophage activation by staphylococcal exotoxins; Fleming SD et al.; We investigated the ability of staphylococcal enterotoxins A and B, exfoliative toxins A and B, and toxic shock syndrome toxin 1 to activate macrophages . All of the toxins tested had the potential to stimulate tumoricidal activity in peritoneal macrophages from lipopolysaccharide-responsive C3HeB/FeJ mice . In contrast, none of the toxins activated cytotoxicity in lipopolysaccharide-unresponsive macrophages from C3H/HeJ mice . We also studied toxin stimulation of monokine secretion . Staphylococcal enterotoxin A, toxic shock syndrome toxin 1, and both exfoliative toxins triggered C3HeB/FeJ macrophages to secrete tumor necrosis factor alpha, but enterotoxin B induced only marginal amounts of tumor necrosis factor . All of the toxins used stimulated interleukin-6 production by macrophages from both strains of mice . Nitric oxide is produced in response to the exfoliative toxins only by the lipopolysaccharide-responsive macrophages . These results suggest that macrophages respond differently to several staphylococcal exotoxins. Eur J Immunol, 1991 Nov, 21(11), 2703 - 9 Interferon-gamma and growth factor production by murine T cells derived from three different lymphoid tissues; Hoiden I et al.; Various antigen-presenting cells and the environment in different lymphoid tissues have been suggested to influence the type of lymphokine produced by T cells . We have investigated the mitogen-induced proliferation, interferon-gamma (IFN-gamma) and growth factor production by cells isolated from spleen, mesenteric and peripheral (axillary, brachial and inguinal) lymph nodes (LN) . We found that stimulation with concanavalin A or staphylococcus enterotoxin B induced IFN-gamma synthesis in spleen cells but not in LN cells . Proliferation and growth factor production were comparable in the three cell populations . The addition of the phorbol ester phorbol 12-myristate 13-acetate (PMA), which is commonly used as a substitute for accessory cells, did not influence the IFN-gamma synthesis by LN cells . The growth factor production was, on the other hand, elevated by the addition of PMA . A high number of IFN-gamma-producing peripheral LN cells were obtained if they were stimulated in the presence of splenic adherent cells . The growth factor synthesis was marginally affected by the presence of these cells . Thus, splenic adherent cells provide a co-stimulatory signal to the T cell necessary for IFN-gamma synthesis. Plant Mol Biol, 1991 Nov, 17(5), 1013 - 21 Expression of antifreeze proteins in transgenic plants; Hightower R et al.; The quality of frozen fruits and vegetables can be compromised by the damaging effects of ice crystal growth within the frozen tissue . Antifreeze proteins in the blood of some polar fishes have been shown to inhibit ice recrystallization at low concentrations . In order to determine whether expression of genes of this type confers improved freezing properties to plant tissue, we have produced transgenic tobacco and tomato plants which express genes encoding antifreeze proteins . The afa3 antifreeze gene was expressed at high steady-state mRNA levels in leaves from transformed plants, but we did not detect inhibition of ice recrystallization in tissue extracts . However, both mRNA and fusion proteins were detectable in transgenic tomato tissue containing a chimeric gene encoding a fusion protein truncated staphylococcal protein A and antifreeze protein . Furthermore, ice recrystallization inhibition was detected in this transgenic tissue. J Biomol NMR, 1991 Nov, 1(4), 439 - 46 Measurement of 15N-13C J couplings in staphylococcal nuclease; Delaglio F et al.; 15N-C alpha and 15N-C' J couplings were measured for the backbone of staphylococcal nuclease, uniformly enriched with 15N and 13C . It is found that the 1JC'N coupling is similar for beta-sheet, J = 14.8 +/- 0.5 and for alpha-helix, J = 14.8 +/- 0.4 but tends to be larger for the unstructured N- and C-terminal ends of the protein (J = 15.6 +/- 0.5) . On average, 1JNC alpha are smaller for alpha-helical residues (J = 9.6 +/- 0.3 Hz) compared to beta-sheet (J = 10.9 +/- 0.8 Hz) and a substantial difference is observed for 2JNC alpha in alpha-helices (J = 6.4 +/- 0.4 Hz) and beta-sheets (J = 8.3 +/- 0.8 Hz). J Immunol, 1991 Nov 1, 147(9), 3080 - 6 Differential sensitivity of virgin and memory T lymphocytes to calcium ionophores suggests a buoyant density separation method and a model for memory cell hyporesponsiveness to Con A; Miller RA et al.; Previous work from this laboratory has indicated that murine memory T cells differ from virgin T cells in that the former are more resistant to agents that alter intracellular {Ca}i . We have used this difference to devise a method for separating virgin from memory T cells by centrifugation over an ionomycin-containing Percoll step gradient after brief exposure to 2 microM ionomycin . Under these conditions, those T cells that are most sensitive to ionomycin-induced changes in {Ca}i become more dense and therefore travel further into the Percoll/ionomycin gradient than cells that are more resistant to ionomycin . We show that the ionomycin-resistant cell population is enriched for cells that express high levels of Pgp-1 (CD44), and low levels of CD45RB, and thus appears to consist largely of memory T cells . Both CD4 and CD8 cells can be divided into Pgp-1hi and Pgp-1lo subsets in this way . Cells recovered from such a gradient and washed to remove the ionomycin appear normally functional, i.e., neither more nor less responsive to mitogens and costimuli than untreated cells . Limiting dilution methods show that the ionomycin-sensitive (virgin) subset contains most of the Con A-responsive precursors for cytotoxicity, and most of the cells able to produce IL-2 in responses to Con A or staphylococcal enterotoxin B . Ag-specific helper memory cells are, however, found predominantly in the ionomycin-resistant fraction of the spleen and draining lymph nodes of mice infected with Schistosoma mansoni . Changes in resistance to calcium signal development may represent a fundamental distinction between virgin and memory T cells, and could contribute to differences in activation requirements between these two cell subsets. Enferm Infecc Microbiol Clin, 1991 Nov, 9(9), 543 - 6 {Effect of subinhibitory concentrations of beta-lactams on the production of slime, surface hydrophobicity and adhesion of Staphylococcus epidermidis}; Martinez-Martinez L et al.; The activity of subinhibitory concentrations of oxacillin, imipenem, cefalotin, cefuroxime, cefotaxime and amoxycillin-clavulanic acid upon slime production, surface hydrophobicity and polystyrene adherence of S . epidermidis was evaluated . Slime production and polystyrene adherence of three Staphylococcus epidermidis strains was assessed using test tube (safranin stained film) or in microtiter plate . The surface hydrophobicity was determined using a biphasic system (water/p-xylene) . Using one-half and one-quarter of MIC for all antibiotics tested, a reduction in slime production and polystyrene adherence was observed in all three strains used . Regarding surface hydrophobicity, in one of the strains used we have observed a rise in surface hydrophobicity values as compared to control strains whenever one-half of MCI was used for all six antimicrobial agents and also with one-quarter of amoxicillin-clavulanate MCI . Subinhibitory MCI of all six antibiotics tested inhibits slime production and adherence of Staphylococcus epidermidis . This inhibitory effect is not related to changes in surface hydrophobicity. Zh Mikrobiol Epidemiol Immunobiol, 1991 Nov, (11), 45 - 7 {The choice of a method of isolating human IgG F(ab)2 fragments for determining antibodies to staphylococcal protein A}; Minster AB et al.; The comparative study of two methods of the proteolysis of IgG with the aim of obtaining F(Ab)2-fragments from the blood sera of patients and healthy donors has been made . Different methods for the isolation of F (ab)2-fragments, such as gel filtration on Sephadex G-200, affinity chromatography on protein A-BrCN-sepharose, reprecipitation with zinc sulfate, have been analyzed . For further work the method of the peptic decomposition of whole serum with subsequent salting out with ammonium sulfate and gel filtration on Sephadex G-200 has been chosen. Immunobiology, 1991 Nov, 183(5), 433 - 50 Crosslinked staphylococcal enterotoxin B stimulates CD8+ T cells only in the presence of unlinked costimulator signals; Miethke T et al.; The superantigen staphylococcal enterotoxin B (SEB) binds to class II MHC expressing cells and subsequently causes selective activation of T cells carrying appropriate T cell receptor (TCR) V beta chains . Apparently SEB acts as a bifunctional molecule by bridging class II MHC structures with the appropriate TCR-V beta chains . This assumption predicts that immobilized SEB ought to stimulate purified, class II MHC negative murine T cells . We show here that immobilized SEB lacks the ability to trigger murine CD8 T cells . Responsiveness obtained at a high T cell concentration is due to contaminating class II MHC-positive lymphocytes . Complementation of the culture system with syngeneic irradiated B cells blasts effectively restores responsiveness . The proliferating cells exhibit SEB specific cytotoxicity and a bias for V beta 8 expression . Since no evidence for leakiness of SEB covalently bound to sephadex beads was obtained, the data imply that immobilized SEB in fact binds to the TCR of T cells expressing the appropriate V beta chains . However, for primary activation additional costimulatory signals are required which can be provided in an unlinked fashion by activated B cells . Resting B cells are activated by immobilized SEB to cells expressing high costimulator activity . As such, the data point out a third function of SEB. J Antimicrob Chemother, 1991 Nov, 28(5), 681 - 94 Screening tests for the detection of methicillin resistance in Staphylococcus epidermidis; Hedin G et al.; Methods to detect resistance to methicillin in Staphylococcus epidermidis were studied in order to find a rapid screening test suitable for routine use . One hundred and forty-nine clinical isolates, 16 isolates from skin of healthy people and two reference strains were studied . Hypersecretion of beta-lactamase as a cause of methicillin resistance was eliminated in the strains studied . Tube and microtitre breakpoint, agar breakpoint and disc diffusion methods were compared . The breakpoint for methicillin resistance used was 16 mg/L in broth and 10 mg/L in agar . The discs used contained 1 and 5 micrograms oxacillin and 5 and 10 micrograms methicillin . Turbidimetric measurements in broth during incubation were carried out using the Bioscreen analysing system . The skin strains were founf to be susceptible in all tests . Using an inoculum of 10(7) cfu/mL 111/149 clinical isolates were classified as resistant after incubation for 24 h at 35 degrees C using the tube and microtitre breakpoint tests, incubation for 72 h did not increase this rate . When an inoculum of 10(5) cfu/mL was used 73% of these strains were identified within 24 h and all within 72 h with the tube breakpoint test . Using the microtitre breakpoint test, with an inoculum of 10(5) cfu/mL or lower, all resistant strains were not detected within 48 h . All agar breakpoint tests required 48 h incubation for reliable results . Only the 1 microgram oxacillin disc always separated strains found to be resistant or susceptible in the tube breakpoint test . The zone of inhibition was clearly readable after 16 h of incubation at 35 degrees C. Can J Microbiol, 1991 Nov, 37(11), 877 - 80 Assessment of two commercial agglutination kits for detecting Escherichia coli heat-labile enterotoxin; Speirs J et al.; Two commercial agglutination kits, a reserved passive agglutination test (VET-RPLA) and a staphylococcal coagglutination test (Phadebact ETEC-LT Test), were compared with two cell culture assays (Y-1 and Vero) and GM1 ganglioside enzyme-linked immunosorbent assay (GM1-ELISA) for sensitivity in detecting Escherichia coli heat-labile enterotoxin (LT) . Of 48 toxigenic strains, 23 were positive by all assays . One strain was negative only by the Phadebact test . Four strains, all LT-II producers, were positive by cell culture only . For LT-I detection, the Phadebact test was the least sensitive but was simple and rapid; VET-RPLA was simple, sensitive, and a good substitute for cell culture or GM1-ELISA. FEMS Microbiol Lett, 1991 Nov 1, 68(1), 23 - 6 Characteristics of extracellular protein production by a plasmidless derivative of Staphylococcus simulans biovar staphylolyticus; Nitterauer JD et al.; A derivative of Staphylococcus simulans biovar staphylolyticus cured of all five plasmids present in the wild-type organism was developed, and the characteristics of extracellular protein production by this plasmidless strain were compared to those of the wild type . Although staphylolytic endopeptidase (lysostaphin) and beta-lactamase are known to be plasmid encoded, analysis of this cured strain revealed that most other extracellular proteins are chromosomally encoded. FEMS Microbiol Lett, 1991 Nov 1, 68(1), 119 - 22 Characterization of staphylococcal plasmids hybridizing with the fosfomycin resistance gene fosB; Etienne J et al.; The distribution of the fosB gene, coding for fosfomycin resistance, in 105 fosfomycin-resistant isolates of Staphylococcus from various geographical areas, was studied by Southern blot hybridization . Nucleotide sequences related to fosB were detected in 36 strains belonging to five species . Plasmids bearing fosB were often of a size similar to that of pIP1842 (2.54 kb) in S . epidermidis, most often small (2.4 to 4.1 kb) in other species including S . aureus where a 2.7-kb plasmid was found in 16 out of the 18 strains studied . The fosB gene was geographically dispersed since it was present in six different locations in France and also in Japan . The weak hybridization observed with plasmid DNA of certain strains of S . aureus, S . epidermidis, S . haemolyticus, S . saprophyticus, and S . warneri may indicate gene heterogeneity for fosfomycin resistance in Staphylococcus spp. Nippon Seikeigeka Gakkai Zasshi, 1991 Nov, 65(11), 1112 - 9 {Haematogenous osteomyelitis induced by strain SMU-0611 of Staphylococcus warneri in mice}; Matsuoka M; Strain SMU-0611 of Staphylococcus warneri isolated from clinical specimens (1.25 x 10(9) colony forming units) was intravenously administered into mice . Strain SMU-0611 caused remarkable inflammation characterized by roentgenographically recognizable changes in bone at 14 days after the injection . A number of organisms were detected in the bone marrow for as long as 35 days after the injection, suggesting specific lodgement of the strain in mouse bone marrow . Concerning the X-ray features of the mice, multiple foci of osteolytic changes were shown in the metaphysis of the femur and the tibia obtained 14 days after the injection . However, these changes did not aggravate at all for 56 days after the injection. DNA Cell Biol, 1991 Nov, 10(9), 663 - 9 Restriction fragment fingerprint and genome sizes of Staphylococcus species using pulsed-field gel electrophoresis and infrequent cleaving enzymes; Poddar SK et al.; Large restriction fragments of genomic DNA from Staphylococcus species were separated by pulsed-field gel electrophoresis (PFGE) . Five different strains of S . aureus (ISP8, SAU3A, PS96, ATCC 6538, ATCC 15564) and three representative strains of S . haemolyticus SM102, S . warneri MCS4, S . cohnii LK478 from human hosts, and one strain of S . aureus (ATCC 8432) from an avian host were used in this study . Since Staphylococcus is A + T rich (approximately 67%), restriction fragments were obtained by digesting chromosomal DNA with endonucleases that recognize GC-rich sequences . Five enzymes Csp I, Sma I, Ecl XI, Ksp I, or Sac II were used for generation of few (7 to 16) distinctly separated fragments, with average sizes in the range of 200-300 kb . The size distribution of restriction fragments for each enzyme for each strain produced a strain-identifying fingerprint, and the genome size of each strain was determined from such restriction fragments separated by PFGE. J Clin Ultrasound, 1991 Nov-Dec, 19(9), 555 - 60 Superficial masses with color flow Doppler imaging; Mitchell DG et al.; Color Doppler imaging findings and spectral waveforms were reviewed for 21 superficial masses in which color Doppler imaging revealed flow . This series included 5 benign hyperplastic lymph nodes, 5 malignant masses, 2 staphylococcus abscesses, and 9 pseudoaneurysms . Benign hyperplastic nodes had a vascular pattern consisting of prominent central flow with a branching radial pattern, reflecting the morphology of lymph nodes . One metastasis from melanoma demonstrated abundant peripheral flow and central avascularity, while the other 4 malignant masses and the 2 abscesses had sparse internal flow . All pseudoaneurysms had a to-and-fro imaging and spectral pattern (into the mass during systole, out during diastole), and/or a swirling pattern on real-time images (8 of 9 each) . Doppler spectral analysis revealed continuous forward flow during diastole for all other masses and abscesses . Waveforms appeared similar for benign and malignant masses, and for abscesses . Conventional image-directed Doppler examinations performed prior to color Doppler studies failed to reveal flow in 2 partially thrombosed pseudoaneurysms, 1 malignant mass, and 1 abscess . Benign hyperplastic nodes, malignant masses, and pseudoaneurysms had distinctive color Doppler image appearances in this series, although demonstration of flow within a mass does not eliminate the possibility of abscess . Proper use of color and spectral Doppler analysis of superficial masses involves more than mere detection or exclusion of flow. J Clin Invest, 1991 Nov, 88(5), 1531 - 9 Escherichia coli hemolysin is a potent inductor of phosphoinositide hydrolysis and related metabolic responses in human neutrophils; Grimminger F et al.; Escherichia coli hemolysin (Hly) is a proteinaceous pore-forming exotoxin that probably represents a significant virulence factor in E . coli infections . We investigated its influence on human polymorphonuclear neutrophils (PMN), previously identified as highly susceptible targets . Hly provoked rapid secretion of elastase and myeloperoxidase, generation of superoxide, and synthesis of platelet-activating factor (PAF) and lyso-PAF . Concomitantly, marked phosphatidylinositol (PtdIns) hydrolysis with sequential appearance of the inositol-phosphates, inositol-phosphates, inositol triphosphate, diphosphate, and monophosphate, respectively, and formation of diacylglycerol, occurred . The metabolic responses displayed distinct bell-shaped dose dependencies, with maximum events noted at low toxin concentrations of 0.1-0.5 hemolytic units per milliliter . PtdIns hydrolysis and metabolic responses elicited by Hly exceeded those evoked by optimal concentrations of formylmethionyl-leucyl phenylalanine, PAF, leukotriene B4, A23187, or staphylococcal alpha-toxin . The toxin-induced effects were sensitive toward modulators of PMN stimulus transmission pathways (pertussis toxin, the kinase C inhibitor H7, and phorbol myristate acetate "priming") . We conclude that the marked capacity of low doses of Hly to elicit degranulation, respiratory burst, and lipid mediator generation in human PMN probably envolves signal transduction via PtdIns hydrolysis. Biochem Biophys Res Commun, 1991 Oct 31, 180(2), 742 - 7 Identification of a site for carboxyl methylation in human alpha-globin; Ladino CA et al.; The human erythrocyte protein carboxyl methyltransferase modifies unusual protein D-aspartyl and L-isoaspartyl residues which arise spontaneously from internal rearrangements accompanying asparaginyl deamidation and aspartyl isomerization . A site of methylation associated with alpha-globin in intact cells has been identified by peptide mapping of radiolabeled globin isolated from human erythrocytes previously incubated with L-{methyl-3H}methionine . The site is located in a Staphylococcus V8 peptide containing residues 1-30 of alpha-globin . Two potential sources of methylation sites are present in this sequence at Asp-t and Asn-9. Proc Natl Acad Sci U S A, 1991 Oct 15, 88(20), 9287 - 91 Monoclonal antibody-targeted superantigens: a different class of anti-tumor agents; Dohlsten M et al.; The bacterial superantigen staphylococcal enterotoxin (SE) A (SEA) directs cytotoxic T lymphocytes (CTLs) expressing particular sequences of the T-cell receptor (TCR) beta chain to lyse tumor cells expressing major histocompatibility complex (MHC) class II molecules, which serve as receptors for SEs . We now report that chemical conjugates of SEA and the colon carcinoma-reactive monoclonal antibodies (mAbs) C215 or C242 mediate T cell-dependent destruction of colon carcinoma cells lacking MHC class II molecules . SEA was covalently linked to the mAbs C215 and C242 via a PEG-based hydrophilic spacer . The C215-SEA conjugate targeted CD4+ as well as CD8+ CTLs to lyse a panel of colon carcinoma cells lacking MHC class II molecules . T-cell recognition of mAb-SEA conjugates was SEA specific, since SEB-selective T-cell lines with potent cytotoxic activity towards Raji cells coated with SEB did not respond to the C215-SEA conjugate . Unconjugated SEA did not induce T-cell lysis of MHC class II- colon carcinoma cells but efficiently directed CTLs against MHC class II+ Raji cells and certain interferon-treated MHC class II+ colon carcinoma cells . These results suggest that SEA-mAb conjugates retain the SEA-related selectivity for certain TCR beta-chain variable region (V beta) sequences but, in contrast to unconjugated SEA, mediate the TCR interaction in a MHC class II-independent manner . The cytotoxic activity mediated by C215-SEA and C242-SEA conjugates was blocked by excess of C215 mAb and C242 mAb, respectively, showing that the specificity in the targeting of mAb-SEA conjugates is defined by the antigen reactivity of the mAb . These results demonstrate that bacterial superantigens may be successfully conjugated to mAb with preserved T cell-activating capacity . The circumvention of MHC class II binding of SEs by conjugation to mAb suggests that such conjugates may find general application as antitumor agents, taking advantage of the extreme T cell-activating potency of superantigens. Cornell Vet, 1991 Oct, 81(4), 389 - 95 Antibiotic-responsive generalized nonlesional pruritus in a dog; Miller WH Jr; A 15-year-old dog was evaluated for a nonresponsive generalized pruritic condition of 5 months duration . Routine diagnostic testing, including intradermal testing with 63 inhaled allergens and the feeding of a home-cooked hypoallergenic diet, failed to define the cause of the pruritus . An intradermal skin test with a staphylococcal cell wall/toxoid mixture and a skin biopsy of the skin test site suggested that the dog had a bacterial hypersensitivity . Antibiotic therapy eliminated the pruritus and the dog's pruritus was successfully managed for 3 years with the combined use of subtherapeutic dosages of antibiotics and a commercial staphylococcal vaccine. Nippon Kyobu Geka Gakkai Zasshi, 1991 Oct, 39(10), 1932 - 6 {Mitral prosthetic valve endocarditis diagnosed by transesophageal echocardiography--a surgical case report}; Shimono T et al.; The patient was a 39-year-old female who had undergone mitral valve replacement 2 years previously . Staphylococcus epidermidis was detected on blood culture . Transesophageal echocardiography revealed vegetation attached to the left atrial site of the mitral prosthesis, whereas precordial echocardiography did not reveal any abnormal echo structure . The patient was performed an emergency operation, during which the echocardiographic finding was confirmed . We conclude that performance of transesophageal echocardiography is useful when clinical features suggest prosthetic valve endocarditis. J Clin Pathol, 1991 Oct, 44(10), 873 - 4 Staphylococcus lugdunensis; Barker KF et al.; A fatal case of penicillin resistant Staphylococcus lugdunensis endocarditis on a native valve damaged by rheumatic fever is described . A retrospective examination of 978 tube coagulase negative staphylococcal blood culture isolates was also performed to determine how often this species is isolated . None of the 978 isolates was identified as S lugdunensis . It is concluded that ornithine decarboxylase production is the only reliable method of identifying this species. J Appl Bacteriol, 1991 Oct, 71(4), 347 - 53 Conversion of biological and immunological properties during a process of decapsulation in a strain of Staphylococcus hyicus; Yoshida E et al.; Repeated subculture at 42 degrees C of Staphylococcus hyicus strain ST67P, which exhibits streaming-type growth in a soft-agar medium, yielded three variants, ST67L, ST67S and ST67C, which had different colonial morphologies; small compact colonies possessing long and short tails and perfect compact colonies . The parent strain and ST67L respectively gave strong and weak positive intensity when stained by rabbit antisera prepared by capsular type I and II strains of Staph . epidermidis conjugated with fluorescein isothiocyanate . Variant ST67L gave a positive result with antiserum prepared by capsular type I strain and no staining was observed with variants ST67S and ST67C against these antisera preparations . Strain ST67C had the lowest virulence although no remarkable difference was shown between the parent strain and variants ST67L and ST67S . The cell volume index of the parent strain was 1.35, 2.43 and 3.71 times larger than those of ST67L, ST67S and ST67C, respectively . The converting activity of rabbit anti-ST67P strain serum absorbed by strain ST67C required four times more of the organisms than strain ST67P, changing the colonial morphology of the strain from diffuse to compact type by the addition of antiserum to soft agar medium . Positive coagulase and false positive clumping factor reaction were shown in variants ST67C, but no remarkable alteration was observed with 19 biochemical properties determined by a conventional identification kit . In ulta-thin sections of the parent strain labelled with rabbit anti-strain ST67P serum conjugated with ferritin, large capsule surrounded by ferritin granules were demonstrated by electron microscopy.(ABSTRACT TRUNCATED AT 250 WORDS) Br J Clin Pharmacol, 1991 Oct, 32(4), 433 - 9 Nicardipine sustained release in hypertension; Webster J et al.; 1 . A novel formulation of nicardipine (25% standard, 75% sustained release--SR) was evaluated in mild hypertension in a double-blind, randomized, placebo-controlled comparison with standard nicardipine (STD), using clinic measurements (Hawksley) augmented by home recorded blood pressures (Copal UA 251) . 2 . At 2 h after dosing (peak effect) both STD nicardipine (30 mg three times daily) and SR nicardipine (60 mg twice daily) for 28 days produced a highly significant reduction in sitting and standing blood pressure . The mean sitting blood pressure was reduced by 20/16 mm Hg (STD) and by 25/18 mm Hg (SR) compared with placebo . 3 . Predose (8-11 h after last dose of STD, 12-15 h after last dose of SR) the reductions in sitting blood pressure relative to placebo were 11/6 mm Hg (STD) and 14/7 mm Hg (SR) . 4 . Home recordings confirmed the hypotensive effect of both formulations . Both exhibited a distinct 'peak dose' effect between 1-3 h after dosing . The effect of the SR formulation was sustained throughout the 12 h dosing interval . 5 . Of the 60 patients entering the study, one died of unexplained staphylococcal septicaema, two were withdrawn for non drug-related reasons and 14 (32%) were withdrawn because of adverse effects on active therapy (headaches, facial flushing, leg oedema, chest pain, dizziness) . 6 . In the 43 patients who completed the study adverse symptoms were reported more frequently while they were on the two active formulations of nicardipine compared with placebo . Most of these reactions were again of vasodilator origin.(ABSTRACT TRUNCATED AT 250 WORDS) Ethiop Med J, 1991 Oct, 29(4), 149 - 61 The incidence of methicillin resistant S . aureus strains in clinical specimens in relation to their beta-lactamase producing and multiple-drug resistance properties in Addis Abeba; Geyid A et al.; From December 1987 to July 1988, a total of 17,142 clinical specimens were examined at the National Research Institute of Health (NRIH), Addis Abeba, to determine the incidence of methicillin resistant S . aureus (MRSA) strains . Coagulase positive Staphylococcus spp . were isolated from 355 specimens . Two hundred and forty-nine 249 (70%) isolates were tested for methicillin resistance by minimum inhibition concentration method (MIC) of which 76 (30.5%) were found to be MRSA and 173 (69.5%) were methicillin sensitive S . aureus (MSSA) strains . The presence of beta-lactamase production was determined in the 355 S . aureus isolates using the rapid Iodometric and Nitrocefin methods and 252 (71%) isolates were found to be beta-lactamase procedures . Furthermore, 47 (62%) of the 76 MRSA isolates and 140 (81%) of the 173 MSSA isolates were beta-lactamase positive strains . The sensitivity pattern of all the S . aureus isolates against 11 common drugs indicated that the majority (80%) of the MRSA strains were multipledrug resistant while 4 (8%) were not resistant to any of the drugs tested . Among the antibiotics, vancomysin and clindamycin were effective against all S . aureus isolates . It was also found that 41 (54%) of the MRSA strains were both betalactamase producers and multiple-drug resistant isolates; of the latter, 36 (87.8%), strains were isolated from pus specimens of patients with post-operative wound infections . The results of this study show that MRSA strains are quite prevalent among specimens referred to the NRIH. Int J Cardiol, 1991 Oct, 33(1), 83 - 8 Profile of right-sided endocarditis: an Indian experience; Grover A et al.; The clinical profile of right-sided infective endocarditis in India was studied from a review of records of patients with infective endocarditis admitted to this hospital . From November 1982 to November 1989, 109 patients with infective endocarditis showed vegetations on cross-sectional echocardiography confirming the diagnosis of infective endocarditis . In 19 (17.4%) patients, only the right side of the heart was involved: specifically the tricuspid valve alone in 10; tricuspid and pulmonary valves in 4; tricuspid valve and right ventricular outflow tract in 1; tricuspid valve and right ventricular free wall in 1; pulmonary valve alone in 2; and bifurcation of pulmonary trunk in 1 . Eleven patients (57.9%) had underlying congenital heart disease whereas the remaining 8 patients (42.1%) did not have any underlying heart disease . The latter group, therefore, had isolated right-sided infective endocarditis . Previous illnesses leading to isolated right-sided infective endocarditis were: puerperal sepsis in 4; septic abortion in 1; staphylococcal pneumonia in 2; and epididymoorchitis in one . Eight out of 11 patients with congenital heart disease did not report any previous illness . In the remaining 3, right-sided endocarditis followed cardiac surgery in one; dental extraction without prophylaxis in one; and pulmonary balloon valvoplasty in one . All patients with isolated right-sided infective endocarditis had features of septicaemia, but a murmur of tricuspid regurgitation was audible in only 4 (50%) of them . We conclude that, unlike western reports, the pattern of right-sided infective endocarditis in India is different . No drug addict with right-sided infective endocarditis was seen; puerperal sepsis and septic abortion were the commonest causes of isolated right-sided infective endocarditis.(ABSTRACT TRUNCATED AT 250 WORDS) Ann Hematol, 1991 Oct, 63(4), 223 - 6 Immunological characterization of canine hematopoietic progenitor cells; Hahn J et al.; Canine hematopoietic progenitor cells were characterized by separation with monoclonal antibodies . Depleted and enriched fractions were studied for growth of CFU-GM in semisolid agar and for repopulating capacity of lethally irradiated dogs . CFU growth was not reduced by depletion of marrow using monoclonal antibodies F 3-20-7 (anti-dog Thy-1), MT606 (anti-human CD 6), and IOT2a (anti-human DR) . CFU growth was variable following treatment with the anti-canine T-cell antibody MdT-P 1 and immunomagnetic bead separation . It was regularly enriched when MdT-P 1 treatment was followed by immunorosetting with staphylococcal protein A-loaded sheep red blood cells and density gradient separation . Lethally irradiated dogs were reconstituted by autologous marrow depleted of MdT-P 1-positive cells using immunorosetting and density gradient centrifugation, whereas immunomagnetic bead-depleted marrow was ineffective . Fluorescence-activated cell sorting showed enrichment of hematopoietic progenitor cells in the weakly MdT-P 1-positive fraction. Postgrad Med, 1991 Oct, 90(5), 58 - 66, 69-73 Pneumonia . Pearls for interpreting patients' radiographs; Montgomery JL; The chest radiograph can detect pneumonia, but laboratory evaluation is needed to determine the specific causative organism . However, before these results become available, a presumptive diagnosis can be made with the help of chest radiography . A lobar pattern on radiography is usually produced by pneumococcal and Klebsiella infections . A lobular (bronchopneumonia) pattern may be produced by Staphylococcus, gram-negative organisms, and anaerobes . An interstitial pattern results from viral, Mycoplasma, and Pneumocystis carinii infections . Mixed patterns may also occur . There is great variation in the presentation of each infection . However, pertinent clinical information, epidemiologic factors, and associated radiographic findings (eg, adenopathy, pleural effusion, cavitation) are helpful in further limiting diagnostic possibilities. Infect Immun, 1991 Oct, 59(10), 3667 - 72 Influence of major histocompatibility complex haplotype on the mitogenic response of T cells to staphylococcal enterotoxin B; Robinson JH et al.; The abilities of antigen-presenting cells (APC) from nine independent major histocompatibility complex haplotypes and a number of intra-H-2 recombinant congenic strains of mice to present staphylococcal enterotoxin B (SEB) and induce proliferation in murine T-cell receptor V beta 8+ T-cell clones were compared . SEB presented by APC of all haplotypes tested induced significant responses in each of the T-cell clones . The magnitude of response was similar for most haplotypes, but there were limited quantitative differences between certain haplotypes . SEB presented by APC from H-2b mice as well as the intra-H-2 recombinant strains B10.GD and B10.A(4R), which do not express cell surface I-E (designated I-E-), induced the poorest T-cell responses . However, APC from AfE-, AsE-, and AqE- mice were as potent in SEB presentation as APC expressing both I-A and I-E . Antibodies against I-E were more effective than anti-I-A antibodies at inhibiting responses to SEB presented by APC expressing both I-A and I-E, whereas responses induced by APC expressing I-A but not I-E were blocked by antibodies against I-A . Thus, our results show that I-A can present SEB efficiently but that expression of both I-A and I-E on the same APC results in presentation of SEB predominantly by I-E . In addition, experiments using four distinct I-E- strains of mice indicate that I-A alleles differ in their ability to present SEB. Cell Immunol, 1991 Oct 1, 137(1), 61 - 71 Induction of interleukin-1 in human monocytes by the superantigen staphylococcal enterotoxin A requires the participation of T cells; Gjorloff A et al.; Nanogram quantities of the bacterial superantigen Staphylococcal Enterotoxin A (SEA) induced significant amounts of extracellular IL-1 alpha and IL-1 beta in human peripheral blood mononuclear cells . Induction of maximal IL-1 alpha and IL-1 beta levels by lipopolysaccharide (LPS) required microgram quantities . LPS induced detectable extracellular IL-1 content within 3-6 hr and maximal levels were detected already after 12 hr . Induction of IL-1 production by SEA showed a delayed release with peak values after 24-48 hr . IL-1 beta was the major species of IL-1 seen in both SEA- and LPS-stimulated culture supernatants . SEA was in general a relatively stronger inducer of extracellular IL-1 alpha than LPS . SEA-induced extracellular IL-1 production in human monocytes was entirely dependent on the presence of T cells, whereas addition of T cells to LPS-stimulated purified human monocytes only marginally enhanced the extracellular IL-1 production . The capacity to induce extracellular IL-1 production in monocytes in response to SEA was high in the CD4+ 45RO+ memory T cell subset, whereas CD4+ 45RA+ naive T cells and CD8+ T cells had lower IL-1-inducing capacity . The T cell help for IL-1 production could not be replaced by a panel of T cell-derived recombinant lymphokines added to SEA-stimulated monocytes, including IFN-gamma and TNF, indicating the participation of cell membrane-bound ligands or hitherto unidentified soluble mediators. J Chemother, 1991 Oct, 3(5), 315 - 20 An open study of teicoplanin in the treatment of gram-positive infections; Nathwani D et al.; Teicoplanin, a new glycopeptide antibiotic similar to vancomycin, was evaluated in treating 36 hospitalized patients suffering from various Gram-positive infections . The 36 patients received teicoplanin once daily as a mean intravenous injection of 550 mg/day (range 200-800 mg/day) . Previous antimicrobial therapy was used in 28% of patients . The mean duration of therapy was 7.5 days (range 3-38 days) . The overall clinical success rate was 94% . 24/36 patients (66%) had positive microbiology . Elimination of the pathogens was seen in 75% of all evaluable cases . Four patients with early prosthetic valve endocarditis due to coagulase negative Staphylococcus (3 patients) and Propionibacterium acnes (1 patient) had a favorable clinical and microbiological outcome . No adverse drug reactions were observed . Teicoplanin is safe and effective in the therapy of many different infections caused by Gram-positive bacteria. J Am Acad Dermatol, 1991 Oct, 25(4), 674 - 81 Clinical and bacteriologic evaluation of OPC-7251 in patients with acne: a double-blind group comparison study versus cream base; Kurokawa I et al.; Twenty-eight patients with acne were assigned to 4 weeks of treatment with OPC-7251 (a new fluoroquinolone derivative) 1% cream or the cream base in a double-blind manner to evaluate the antibacterial effect of the drug on resident bacteria in the hair follicles and to evaluate clinical response . Propionibacterium acnes was isolated from 21 of the 28 acne patients . When the number of P . acnes was compared before and after treatment, the posttreatment P . acnes count in the OPC-7251 1% cream group was significantly (p = 0.000) reduced compared with that in the cream base group . OPC-7251 1% cream was also significantly (p = 0.019) superior to the cream base in terms of clinical response . P . acnes and Staphylococcus epidermidis isolated from the acne lesions were selected for their susceptibility to various antibacterial agents . The minimal inhibitory concentration of OPC-7251 against P . acnes and S . epidermidis was 0.10 to 0.20 and 0.024 to 0.10 micrograms/ml, respectively, which indicates that the drug has a potent antibacterial effect. Immunology, 1991 Oct, 74(2), 183 - 90 Role of CD4 molecule in intrathymic T-cell development; Takeuchi Y et al.; We have investigated the role of CD4 molecules in intrathymic T-cell repertoire selection . The administration of monoclonal antibody (mAb) to CD4 in organ culture of murine foetal thymus (FTOC) completely inhibited the development of CD4+8- cells, and additional treatment with anti-class II MHC (Ia) mAb caused no further effects on this inhibition . On the other hand, when the potentially autoreactive cells in Mls-1a mice were monitored by expression of the Mls-1a-reactive V beta 6 gene product of T-cell receptor alpha beta (TcR alpha beta), the treatment with anti-CD4 resulted in the appearance of V beta 6-bearing cells to some extent, but this effect was considerably reinforced by the combinatory use of anti-Ia mAb with anti-CD4 . In a model system where the bacterial superantigen staphylococcal enterotoxin B serves as self-antigen to deplete V beta 8-bearing cells in FTOC, the depletion of V beta 8+ cells was restored partially by anti-CD4 alone but completely by the combination with anti-Ia . These results suggest that CD4 is indispensable for positive selection of all CD4+8- thymocytes, whereas participation of CD4 in negative selection is only partial . It was also observed that the development of TcR alpha beta-bearing cells in the CD4-8- population was inhibited by the treatment with anti-CD4 mAb . In Mls-1a mice, V beta 6-bearing cells were developed in CD4-8+, CD4+8+, and also in CD4-8- populations after anti-CD4 mAb treatment . It is suggested that TcR alpha beta-bearing CD4-8- cells are possibly originated from CD4+ cells and undergo CD4-mediated thymic selection. J Immunol, 1991 Oct 1, 147(7), 2088 - 93 Differential T cell hyporesponsiveness induced by in vivo administration of intact or F(ab')2 fragments of anti-CD3 monoclonal antibody . F(ab')2 fragments induce a selective T helper dysfunction; Hirsch R et al.; Induction of peripheral T cell anergy associated with stimulation through the TCR complex in vivo has been described in mice using chemically modified APC, staphylococcal enterotoxin B, and intact anti-CD3 mAb . In the latter two models, T cell proliferation, IL-2R expression, and lymphokine production have been demonstrated before subsequent induction of hyporesponsiveness, whereas in the former model, these events have not been observed . To further investigate the relationship between mitogenicity and induction of peripheral hyporesponsiveness, mice were treated with either mitogenic intact anti-CD3 mAb or nonmitogenic F(ab')2 fragments of anti-CD3 mAb . T cells from F(ab')2-treated mice demonstrated a selective decrease in helper functions, with minimal effect on CTL function . Specifically, a marked reduction in ability of Th cells to secrete IL-2 when challenged in vitro with mitogen or alloantigen was observed, which persisted for at least 2 mo after mAb administration and which was independent of T cell depletion . Proliferative function was decreased in CD4+ T cells and could not be fully restored with addition of exogenous IL-2 . A helper defect was also evident in vivo, in that F(ab')2-treated mice were deficient in their ability to reject MHC-disparate skin grafts, and in vivo administration of IL-2 reconstituted their ability to reject skin grafts normally . In contrast, T cells from mice treated with intact mAb demonstrated a significant decrease in both CTL and helper functions . A long term reduction in TCR expression on CD4+ cells from F(ab')2-treated mice, and on both CD4+ and CD8+ cells from intact mAb-treated mice was observed . These findings demonstrate that peripheral T cell hyporesponsiveness can be induced in vivo by binding an identical epitope on the TCR complex in the presence or absence of initial proliferation, lymphokine secretion, or IL-2R expression, and that binding to the same epitope can result in varying long term effects on T cell function. Indian Pediatr, 1991 Oct, 28(10), 1125 - 8 Gentamicin therapy: medical audit; Bagga A et al.; In order to evaluate the prescription practices on gentamicin, we screened retrospectively the case records of 600 patients admitted to this hospital . Of these, 100 received gentamicin, in combination with other antibiotics, as the initial treatment . Therapy with gentamicin was considered to be indicated in 71 cases; 62% were below 1 year . Patients with neonatal septicemia, meningitis, serious staphylococcal infections and those who were immunocompromised received appropriate treatment with the drug . All the bacteria cultured were sensitive to the antibiotic . Gentamicin was unnecessarily prescribed to 29 cases including bronchial asthma (n = 7), bronchiolitis (n = 6) and acute gastroenteritis with dehydration (n = 8) . In most of the latter cases, the use of gentamicin indicated the psychologic dependence, of the physician, on the drug . Nine patients showed gentamicin-related nephrotoxicity . Formulation of standard treatment guidelines and regular medical audits are necessary to improve quality of prescribing and avoid misuse of drugs. Biologicals, 1991 Oct, 19(4), 271 - 9 The measurement of staphylococcal protein A by ELISA in immunoglobulin preparations; Lucas C et al.; Chicken antibodies were used to develop an ELISA for the quantitation of parts-per-million levels of protein A in the purification of immunoglobulins or immunoglobulin-like molecules . Quantitation of protein A in the presence of excess human or murine immunoglobulins in this assay was compared with that obtained in ELISAs developed with rabbit antibodies specific either to protein A or to other molecules . Experiments demonstrate that protein A is bound to the immunoglobulins being purified and that this binding affects subsequent recognition by the antibodies used for the assay . Because of these effects and because fragments of protein A might not be detected in assays which rely on Fc binding of protein A, chicken antibodies that bind protein A specifically are an advantage for the quantitation of this protein by ELISA . In addition, comparison of the effect of different types of immunoglobulins on the protein A standard curve suggests that alternatives to including the immunoglobulin under purification with the standards can be utilized. Rev Clin Esp, 1991 Oct, 189(6), 264 - 7 {Complications of liver transplant in intensive care . Experience in 130 cases}; Cisneros Alonso C et al.; Liver transplant is the first therapeutic choice in most of the advanced liver diseases . Nevertheless, its performance originates a number of complications derived from: a) conservation techniques of the organ (in our study a prolonged time of hot ischemia was significantly associated with); b) surgery (all patients who required massive blood transfusions developed metabolic alkalosis); c) the graft itself (all the F 1 . degrees were significantly infected), and d) extrahepatic causes (cyclosporin was responsible for high blood pressure and nephrotoxicity which appeared as oliguria with good response to furosemide, as well as hyperglycemia) . Some other relevant results in our series were: right pleural effusion and thrombopenia which appeared with a high incidence . Infections were usually originated the staphylococcus which grows in half of the cultures . We also want to highlight the short mean stay and the low mortality incidence in the ICU. Cryobiology, 1991 Oct, 28(5), 474 - 82 Enhanced survival of yeast expressing an antifreeze gene analogue after freezing; McKown RL et al.; Yeast, like most organisms, survives poorly under freezing conditions . It has been proposed that after rapid cooling yeast suffers a loss in viability from the recrystallization of intracellular ice . Antifreeze proteins found in the blood of certain polar fishes have been shown to be potent inhibitors of ice recrystallization at very low concentrations . We have examined the feasibility of protecting rapidly cooled yeast cells from freezing damage by inhibiting the recrystallization of intracellular ice through in vivo expression of an antifreeze analogue gene . A chemically synthesized gene encoding a protein similar to but differing from the antifreeze proteins of the fish Pseudopleuronectes americanus (winter flounder) was genetically fused to the 3' end of a truncated staphylococcal Protein A gene . When the fused gene was expressed in the budding yeast Saccharomyces cerevisiae, its cells were shown to produce a new chimeric protein that inhibited the recrystallization of ice in vitro . Yeast cells expressing the chimeric antifreeze protein showed a twofold increase in survival after rapid freezing (95 degrees C/min to -196 degrees C) and moderate rates of warming (26 to 64 degrees C/min) compared to cells lacking the chimeric protein. J Exp Med, 1991 Oct 1, 174(4), 901 - 13 Analysis of T cell stimulation by superantigen plus major histocompatibility complex class II molecules or by CD3 monoclonal antibody: costimulation by purified adhesion ligands VCAM-1, ICAM-1, but not ELAM-1; van Seventer GA et al.; Many ligands of adhesion molecules mediate costimulation of T cell activation . The generality of this emerging concept is best determined by using model systems which exploit physiologically relevant ligands . We developed such an "antigen-specific" model system for stimulation of resting CD4+ human T cells using the following purified ligands: (a) major histocompatibility complex class II plus the superantigen Staphylococcus enterotoxin A, to engage the T cell receptor (TCR); (b) adhesion proteins vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and endothelial leukocyte adhesion molecule 1 (ELAM-1), to provide potential cell surface costimulatory signals; and (c) recombinant interleukin 1 beta (rIL-1 beta)/rIL-6 as costimulatory cytokines . In this biochemically defined system, we find that resting CD4+ T cells require costimulation in order to respond to TCR engagement . This costimulation can be provided by VCAM-1 or ICAM-1; however adhesion alone is not sufficient since ELAM-1 mediates adhesion but not costimulation . The cytokines IL-1 beta and IL-6 by themselves cannot mediate costimulation, but augment the adhesion ligand-mediated costimulation . Direct comparison with the model of TCR/CD3 engagement by CD3 monoclonal antibody demonstrated comparable costimulatory requirements in both systems, thereby authenticating the commonly used CD3 model . The costimulation mediated by the activation-dependent interaction of the VLA-4 and LFA-1 integrins with their respective ligands VCAM-1 and ICAM-1 leads to increased IL-2R alpha (CD25) expression and proliferation in both CD45RA+ CD4+ and CD45RO+ CD4+ T cells . The integrins also regulate the secretion of IL-2, IL-4, and granulocyte/macrophage colony-stimulating factor . In contrast the activation-independent adhesion of CD4+ T cell to ELAM-1 molecules does not lead to T cell stimulation as measured by proliferation, IL-2R alpha expression, or cytokine release . These findings imply that adhesion per se is not sufficient for costimulation, but rather that the costimulation conferred by the VLA-4/VCAM-1 and LFA-1/ICAM-1 interactions reflects specialized accessory functions of these integrin pathways . The new finding that VLA-4/VCAM-1 mediates costimulation adds significance to observations that VCAM-1 is expressed on a unique set of potential antigen-presenting cells in vivo. J Hosp Infect, 1991 Oct, 19(2), 107 - 14 Investigation of nosocomial prosthetic valve endocarditis due to antibiotic-resistant Staphylococcus epidermidis; Menzies R et al.; A reservoir of antibiotic-resistant Staphylococcus epidermidis strains in our cardiac surgery unit appeared to be the source of organisms responsible for three cases of early prosthetic valve endocarditis . Staphylococcus epidermidis isolates recovered from the skin of 13 patients before and after surgery were compared . All were typed by plasmid profile, antimicrobial susceptibility and slime production . The three strains from early prosthetic valve endocarditis resembled the antibiotic-resistant nosocomial strains recovered from the skin of eight patients following surgery and the environment of the operating theatres . These strains expressed resistance to oxacillin, gentamicin, kanamycin and tobramycin and most produced slime, whereas those isolated from the skin of patients at the time of admission were predominantly susceptible to antibiotics and few produced slime. Int Immunol, 1991 Oct, 3(10), 1005 - 13 Failure of T cell receptor V beta negative selection in murine intestinal intra-epithelial lymphocytes; Murosaki S et al.; The intestinal intra-epithelial lymphocytes (IEL) are divided into several subsets on the basis of expression of T cell receptor (TCR) alpha beta and gamma delta, intensity of Thy-1 expression and expression of Lyt-3 chain . To investigate the differentiation pathway of the IEL, we examined the repertoire of V beta segments of T cells in the IEL in BALB/c (H-2d, MIs-1b2a) or AKR/J (H-2k, MIs-1a2b) mice . Among freshly isolated IEL, an appreciable number of T cells bearing V beta 3 or V beta 11, which recognize MIs-2a- or MHC IE-encoded molecules respectively, were detected in BALB/c mice . Similarly, in AKR/J mice, IEL contained appreciable levels of V beta 6-bearing T cells . V beta 3- or V beta 11-bearing T cells in the IEL in BALB/c mice increased to a significant level when incubated with staphylococcal enterotoxin A which specifically stimulates V beta 3- and V beta 11-bearing T cells . Most of IEL without clonal deletion expressed Lyt-2 but not Lyt-3 antigens . Such T cells were hardly detected in other organs, including liver . Our results indicate that TCR alpha beta-bearing intestinal IEL that have not undergone negative selection may have differentiated outside the thymus, presumably at a local site of the intestine and can respond normally to the signal via their TCR. Eur J Immunol, 1991 Oct, 21(10), 2455 - 9 Use of variable human V delta genes to create functional T cell receptor alpha chain transcripts; Sottini A et al.; Previous studies of the human T cell receptor delta genes identified five commonly used V delta segments distinct from any of the known V alpha genes . To define better the relationship between the T cell receptor delta and alpha repertoires we amplified cDNA obtained by polyclonally activated lymphocytes with a common 3' antisense C alpha-specific primer and with five different 5' sense V delta family-specific primers . Amplified products were detected in staphylococcal enterotoxin C2, staphylococcal enterotoxin E, phytohemagglutinin, concanavalin A, anti-CD3 and anti-V beta 8-activated cells, although each cell population expressed a selective pattern of V delta genes . Sequence analysis revealed that each of the known V delta genes can productively rearrange to J alpha segments to produce functional V delta-J alpha-C alpha transcripts . These results argue strongly against the notion that the human V delta and V alpha repertoires are distinct . They further suggest that the restricted delta repertoire observed in many gamma/delta clones results from selection rather than from controlled rearrangements at the T cell receptor alpha/delta locus. J Virol, 1991 Oct, 65(10), 5149 - 56 The herpes simplex virus 1 gene encoding a protease also contains within its coding domain the gene encoding the more abundant substrate; Liu FY et al.; The herpes simplex virus 1 open reading frames UL26 and UL26.5 are 3' coterminal . The larger, UL26 open reading frame encodes a protein approximately 80,000 in apparent molecular weight and contains the promoter and coding sequence of the UL26.5 gene, which specifies a capsid protein designated infected cell protein 35 . The larger product contains in its entirety the amino acid sequence of the smaller protein . We report that the UL26 gene encodes a protease which catalyzes its own cleavage and that of the more abundant product of UL26.5 . By inserting the coding sequence of an epitope to a cytomegalovirus monoclonal antibody and homologs of the immunoglobulin G binding domain of staphylococcal protein A into the 3' termini of the coding domains of the two open reading frames, we identified both products of the cleavage and determined that the cleavage site is approximately 20 amino acids from the carboxyl termini of both proteins. J Infect Dis, 1991 Oct, 164(4), 711 - 9 Effects of staphylococcal toxic shock syndrome toxin 1 on aortic endothelial cells; Lee PK et al.; In staphylococcal toxic shock syndrome, hypotension and shock due to capillary leak may rapidly lead to death of the host . To investigate its pathogenesis, the cytotoxic effects of toxic shock syndrome toxin 1 (TSST-1) on porcine aortic endothelial cells (PAEC) were examined in vitro . TSST-1 killed PAEC (as measured by 51Cr release) in a dose- and time-dependent fashion and was blocked by anti-TSST-1 antibodies . Receptor-mediated endocytosis may be critical for the cytotoxic effects of TSST-1, as killing was inhibited by cold (4 degrees C) and by addition of chloroquine and methylamine . Furthermore, calcium and oxygen appeared necessary for TSST-1 effects on PAEC . Membrane receptor binding studies indicated PAEC bind TSST-1 with high affinity (Kd = 5.7 x 10(-7) M) and had 2.2 x 10(4) receptors/cell . Last, as measured by 125I-labeled albumin flux in a transendothelial permeability model, TSST-1 enhanced the permeability of PAEC monolayers in a dose- and time-dependent manner. FEBS Lett, 1991 Sep 23, 290(1-2), 135 - 8 The Pro117 to glycine mutation of staphylococcal nuclease simplifies the unfolding-folding kinetics; Kuwajima K et al.; Kinetics of unfolding and refolding of a staphylococcal nuclease mutant, in which Pro117 is replaced by glycine, have been investigated by stopped-flow circular dichroism, and the results are compared with those for the wild-type protein . In contrast to the biphasic unfolding of the wild-type nuclease, the unfolding of the mutant is represented by a single-phase reaction, indicating that the biphasic unfolding for the wild-type protein is caused by cis-trans isomerization about the prolyl peptide bond in the native state . The proline mutation also simplifies the kinetic refolding . Importance of the results in elucidating the folding mechanism is discussed. Biochemistry, 1991 Sep 17, 30(37), 8945 - 53 Effects of temperature on the fluorescence intensity and anisotropy decays of staphylococcal nuclease and the less stable nuclease-conA-SG28 mutant; Eftink MR et al.; Frequency-domain fluorescence spectroscopy was used to investigate the effects of temperature on the intensity and anisotropy decays of the single tryptophan residues of Staphylococcal nuclease A and its nuclease-conA-SG28 mutant . This mutant has the beta-turn forming hexapeptide, Ser-Gly-Asn-Gly-Ser-Pro, substituted for the pentapeptide Tyr-Lys-Gly-Gln-Pro at positions 27-31 . The intensity decays were analyzed in terms of a sum of exponentials and with Lorentzian distributions of decay times . The anisotropy decays were analyzed in terms of a sum of exponentials . Both the intensity and anisotropy decay parameters strongly depend on temperature near the thermal transitions of the proteins . Significant differences in the temperature stability of Staphylococcal nuclease and the mutant exist; these proteins show characteristic thermal transition temperatures (Tm) of 51 and 30 degrees C, respectively, at pH 7 . The temperature dependence of the intensity decay data are shown to be consistent with a two-state unfolding model . For both proteins, the longer rotational correlation time, due to overall rotational diffusion, decreases dramatically at the transition temperature, and the amplitude of the shorter correlation time increases, indicating increased segmental motions of the single tryptophan residue . The mutant protein appears to have a slightly larger overall rotational correlation time and to show slightly more segmental motion of its Trp than is the case for the wild-type protein. J Immunol, 1991 Sep 15, 147(6), 1877 - 83 Human IgA and IgG F(ab')2 that bind to staphylococcal protein A belong to the VHIII subgroup; Sasso EH et al.; Staphylococcal protein A (SPA) is a bacterial membrane protein that possesses, in addition to its Fc gamma-binding activity, a distinct specificity for the Fab region of some IgM, IgA, IgG, and IgE . The Fab site that binds to SPA has been localized to the V region of the Ig H chain . In a previous study of human monoclonal and polyclonal IgM, we demonstrated that binding to SPA was highly restricted to molecules of the VHIII subgroup, and that nearly all VHIII IgM were able to bind SPA . The present study examines the VH composition of SPA-binding and SPA-nonbinding fractions of purified human polyclonal IgA, and IgG F(ab')2 fragments . We found that 22% of the IgA and 15% of the IgG F(ab')2 bound to SPA-agarose . Analysis with VH subgroup-specific antisera indicated that the SPA-binding fraction of IgA was dominated by the VHIII subgroup, and the SPA-binding fraction of IgG F(ab')2 contained only VHIII molecules . Furthermore, substantial portions of the total VHIII protein in IgA and in IgG F(ab')2 bound to SPA . We conclude that Fab binding to SPA is both restricted to and highly prevalent among human VHIII molecules, regardless of Ig class . These results suggest that protein A is an Ig superantigen. Am J Ophthalmol, 1991 Sep 15, 112(3), 278 - 82 Anterior chamber aspirate cultures after uncomplicated cataract surgery; Dickey JB et al.; We cultured anterior chamber aspirates of 30 patients who had uncomplicated extracapsular cataract extraction or phacoemulsification . The aspirate was obtained at the time of wound closure . Of 30 patients, 13 (43%) had culture-positive anterior chamber aspirates . The total number of organisms recovered was 18, with three patients having multiple organisms identified . The most commonly isolated organisms were coagulase-negative Staphylococcus sp., occurring in eight of 18 isolates (44%) . No eyes in our study developed endophthalmitis, even though almost one half had viable organisms growing from the anterior chamber aspirates . Inoculum sizes were extremely small (10 to 20 colony-forming units/ml) . This study suggests that in humans, the anterior chamber is capable of clearing a low inoculum of bacteria after cataract surgery without the development of endophthalmitis. Can J Microbiol, 1991 Sep, 37(9), 722 - 4 Comparison of the pathogenicity of three species of coagulase-negative Staphylococcus in a mouse model with and without a foreign body; Ferguson KP et al.; Staphylococcus schleiferi, Staphylococcus lugdunensis, and Staphylococcus epidermidis produce a high incidence of abscesses in a mouse model with an implanted foreign body . We investigated the significance of the foreign body in this process . Fourteen strains of S . schleiferi, S . epidermidis, and S . lugdunensis were tested in our model . A preadhered foreign body was implanted into one mouse group, followed by injection of a test strain . Another group received injection without implant . Abscesses were assessed at 7 days; foreign bodies and infected tissues were cultured . The percent of samples that developed abscesses or were culture positive was compared for each strain . Nearly all mice infected with S . schleiferi developed abscesses and were culture positive . The foreign body made no difference in abscess formation for three of four S . schleiferi but increased the incidence of both organism recovery and abscess for three of five S . epidermidis . The foreign body enhanced abscess formation for four of five S . lugdunensis, with all five strains yielding significantly more culture recovery . Although the pathogenicity of nine strains was increased by the foreign body, five strains yielded high abscess and culture recovery rates that were not enhanced by its presence. Ophthalmology, 1991 Sep, 98(9), 1370 - 5 Effect of intravitreal dexamethasone on ocular histopathology in a rabbit model of endophthalmitis; Maxwell DP Jr et al.; The histologic and clinical effect of intravitreal dexamethasone was studied in a rabbit model of experimentally induced gentamicin sensitive Staphylococcal epidermidis endophthalmitis . The study compared four treatment groups: vitrectomy alone (group I), vitrectomy plus intravitreal gentamicin (group II), vitrectomy plus intravitreal gentamicin and dexamethasone (group III), and intravitreal gentamicin and dexamethasone without vitrectomy (group IV) . All eyes treated with dexamethasone, with or without vitrectomy, exhibited less clinical and histologic manifestations of inflammation . This study suggests that suppression of inflammation through the use of intravitreal dexamethasone leads to preservation of ocular architecture with potentially improved retinal function and visual benefit. J Mol Biol, 1991 Sep 5, 221(1), 7 - 14 In a staphylococcal nuclease mutant the side-chain of a lysine replacing valine 66 is fully buried in the hydrophobic core; Stites WE et al.; The crystal structure of the staphylococcal nuclease mutant V66K, in which valine 66 is replaced by lysine, has been solved at 1.97 A resolution . Unlike lysine residues in previously reported protein structures, this residue appears to bury its side-chain in the hydrophobic core without salt bridging, hydrogen bonding or other forms of electrostatic stabilization . Solution studies of the free energy of denaturation, delta GH2O, show marked pH dependence and clearly indicate that the lysine residue must be deprotonated in the folded state . V66K is highly unstable at neutral pH but only modestly less stable than the wild-type protein at high pH . The pH dependence of stability for V66K, in combination with similar measurements for the wild-type protein, allowed determination of the pKa values of the lysine in both the denatured and native forms . The epsilon-amine of this residue has a pKa value in the denatured state of 10.2, but in the native state it must be 6.4 or lower . The epsilon-amine is thus deprotonated in the folded molecule . These values enabled an estimation of the epsilon-amine's relative change in free energy of solvation between solvent and the protein interior at 5.1 kcal/mol or greater . This implies that the value of the dielectric constant of the protein interior must be less than 12.8 . Lysine is usually found with the methylene groups of its side-chain partly buried but is nevertheless considered a hydrophilic surface residue . It would appear that the high pKa value of lysine, which gives it a positive charge at physiological pH, is the primary reason for its almost exclusive confinement to the surface proteins . When deprotonated, this amino acid type can be fully incorporated into the hydrophobic core. Otolaryngol Head Neck Surg, 1991 Sep, 105(3), 419 - 21 Fine-needle aspiration of diffuse cervical lymphadenopathy in patients with acquired immunodeficiency syndrome; Shapiro AL et al.; Although diffuse cervical lymphadenopathy is one of the earliest and most common findings in patients with AIDS, the appropriate diagnostic approach in these patients has yet to be determined . Fine-needle aspiration (FNA) was performed on 26 patients with AIDS in order to evaluate the role of FNA in patients with diffuse cervical adenopathy . Specimens were sent for cytology, bacterial culture, fungal culture, and acid-fast smear and culture . Ten patients had positive findings, including toxoplasmosis, histoplasmosis, tuberculosis, atypical mycobacterium, and methicillin-resistant staphylococcal infection . All patients with either unilateral adenopathy or lymph nodes 3 cm or larger had positive aspirates . A statistically significant difference between patients with lymph nodes smaller than 2 cm and those with nodes larger than 2 cm was found . Fine-needle aspiration of a representative node in patients with AIDS may allow prompt diagnosis of diffuse lymphadenopathy . Rapid initiation of appropriate treatment can lead to symptomatic improvement . The need for excisional biopsy of involved lymph nodes may be obviated . Fine-needle aspiration is recommended as a diagnostic tool in selected patients with diffuse cervical lymphadenopathy and AIDS. Ophthalmology, 1991 Sep, 98(9), 1376 - 8 Intralenticular infections; D'Mellow G et al.; Antecedent trauma resulting in endophthalmitis is not uncommon . However, primary intralenticular infection is a rare occurrence . Primary intralenticular fungal infection has not been previously reported . The authors present two cases: one of Paecilomyces infection and the other of Staphylococcus epidermidis infection limited to the crystalline lens . Both cases illustrate a delay in diagnosis. J Thorac Imaging, 1991 Sep, 6(4), 60 - 4 Pulmonary d