Inhibition of chemotaxis of neutrophil leukocytes to interleukin-8 by endotoxins of various bacteria.

The effects of endotoxins from various bacteria (Escherichia coli, Klebsiella pneumoniae, Vibrio cholerae, Shigella flexneri, Salmonella typhosa, and Pseudomonas aeruginosa) on chemotaxis of neutrophil leukocytes to formyl peptide and interleukin-8 were tested in an improved chemotaxis assay involving a "sparse-pore" polycarbonate (Nuclepore) membrane in a Boyden-type chamber. The possible chemotactic activity of the endotoxins themselves were tested by the same technique. In addition, the effects of these substances on random motility of neutrophils were tested with a corresponding assay involving similar chambers fitted with membranes of standard pore density. Possible activation of the complement system of serum by each endotoxin was tested with sheep erythrocyte assays and the maximum endotoxin concentration (100 micrograms/ml) used in the chemotaxis and motility assays. All endotoxins inhibited chemotaxis of neutrophils to interleukin-8. No endotoxin affected chemotaxis to formyl peptide or was itself chemotactic for neutrophils. Endotoxin of S. flexneri inhibited random motility of neutrophils, while the others had no such effect. Endotoxins of K. pneumoniae and of P. aeruginosa produced moderate and marked inhibition, respectively, of total complement, as measured by hemolysis of sheep erythrocytes, without affecting the levels of C3c and C4 in these assays. Endotoxins of the other bacteria had no demonstrable effect in any of these assays of complement activation. These results suggest that chemotaxis to interleukin-8 may be mediated by cellular mechanisms different from those involved in chemotaxis to formyl peptide. Furthermore, the presence of these endotoxins could be significant for the suppression of neutrophil accumulation in inflammatory lesions mediated by interleukin-8.     

Strain variation among Bordetella pertussis isolates from Québec and Alberta provinces of Canada from 1985 to 1994

Pulsed-field gel electrophoresis and gene typing were able to differentiate among 3,597 Bordetella pertussis isolates circulating in Alberta and Québec Provinces, Canada, from 1985 to 1994 and distinguish them from the strains used in vaccine production. This study provides a baseline for continued surveillance of prevalent and emerging strains of B. pertussis in Canada.     

Follicular fluid and serum concentrations of myo-inositol in patients undergoing IVF: relationship with oocyte quality

BACKGROUND: The follicular microenvironment is an important determinant of oocyte development. The aim of this study was to examine whether the myo-inositol (MI) content in human follicular fluid (FF) was associated with better oocyte quality. METHODS: A total of 53 patients treated with IVF was recruited to a prospective observational study. FF and serum samples collected were divided into two groups: group A consisted of FF associated with matured and fertilized oocytes, whilst group B was from follicles with immature and unfertilized oocytes. RESULTS: Patient's age, total ampoules of HMG used, days of stimulation, basal levels of FSH, estradiol (E(2)) levels on the day of HCG, and serum MI content were not significantly different between the two groups. FF volume and its MI content were significantly higher in group A compared with group B (P < 0.05). The levels of MI in FF were positively correlated with the amount of E(2) in their corresponding FF samples and also correlated with embryo quality. CONCLUSIONS: We propose that higher concentrations of MI and E(2) in human FF appear to play a role in follicular maturity and provide a marker of good quality oocytes.     

The clinical features of three babies with osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen.

The features of three babies with lethal perinatal osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen were studied. The babies were heterozygous for this substitution at residue 391 in case 1 (0I24), 667 in case 2 (0I51), and 976 in case 3 (0I30). They were all small, term babies who died soon after birth. The ribs were broad and continuously beaded in 0I24, discontinuously beaded in 0I51, and slender with few fractures in 0I30. The overall radiographical classifications were type IIA in 0I24, IIA/IIB in 0I51, and IIB in 0I30. Histological examination confirmed that the long bones were misshapen and porotic. The calcified cartilage trabeculae were covered with an abnormally thin layer of osteoid and the bone trabeculae were thin and basophilic. There was no evidence of lamellar bone or Haversian systems. The osteoblasts remained relatively large and closely spaced. These babies shared many phenotypic features, but differences in the radiographical appearance of the ribs and long bones suggested that there was a gradient of bone modelling capacity from the slender and overmodelled bones in 0I30 to the absence of modelling in 0I24.     

Housing satisfaction for persons with psychiatric disabilities

Provision of residential services to people with mental illness has assumed increasing importance since deinstitutionalization and as community‐ based services have increased. This large‐scale multisite study of housing programs specifically for persons with mental illness examines one of the factors that lead to successful residential tenure for persons with serious mental illness. To date, the Lehman Quality of Life Scale has been used primarily to assess satisfaction with housing in studies of residential services. This article reports on a new measure of housing satisfaction. This new 25‐item instrument was developed, field tested in a variety of housing settings across the country, and analyzed for reliability and validity by a group of housing researchers and clinicians. The implications of using this instrument for future evaluation and research on housing for persons with mental illness are examined. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 581–590, 2003.     

Plasmodium falciparum sexual stage antigens: immunogenicity and cell-mediated responses.

Antibody and cell-mediated immune responses to the transmission-blocking target antigens of Plasmodium falciparum, Pfs 48/45, were determined in infected non-immune patients and in immune individuals from an endemic area. Characterization of the B cell epitopes with monoclonal antibodies showed that there were five regions identifiable but there could be interactions between them causing either competitive or enhancing effects. Sera from infected non-immune patients contained antibodies that would compete with one or more of the mAbs to the different epitopes. Immune responsiveness to purified Pfs 48/45 in P. falciparum-immune adults measured as lymphoproliferation, production of interferon-gamma, or as Pfs 48/45-specific antibody was very limited. This did not appear to be due to MHC class II restriction, to diversity in structure of the parasite antigens or to a failure of immunological memory. The antibody-response data were more consistent with down-regulation of immunity as a result of prolonged exposure to infection.     

Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, Venereal Disease Research Laboratory, and rapid plasma reagin tests in primary syphilis.

Seroreactivity of sera from 109 patients with first-infection primary syphilis was 98.2% in the fluorescent treponemal antibody absorption test, 92.7% in the rapid plasma reagin 18-mm circle card test, 72.5% in the microhemagglutination test (MHA-TP), and 72.5% in the Venereal Disease Research Laboratory test. Seroreactivity of sera from 18 patients with primary syphilis with documented previous infection(s) was 100% in the fluorescent treponemal antibody absorption test, the rapid plasma reagin 18-mm circle card test, and the MHA-TP test and 88.9% in the Venereal Disease Research Laboratory test. The MHA-TP test failed to confirm reactivity in 13 of 79 sera which were reactive in the Venereal Disease Research Laboratory test and in 24 of 101 sera which were reactive in the rapid plasma reagin 18-mm circle card test. Testing another production lot of MHA-TP reagents resulted in even poorer correlation. The reactivity of the MHA-TP test in primary syphilis appeared to vary with the sensitivity of the production lot of reagents.     

Unusual bone marrow manifestations of parvovirus B19 infection in immunocompromised patients

Parvovirus B19 is responsible for a spectrum of disease in humans. The usual bone marrow findings in acute parvovirus infections are marked erythroid hypoplasia and occasional giant erythroblasts. Intranuclear inclusions in developing erythroid precursors are rarely described in children or adults with parvovirus infection, although abundant intranuclear inclusions are commonly observed in the placenta and other tissues in infected fetuses. In this study, 8 patients are reported in whom the first evidence of parvovirus infection was the recognition of numerous intranuclear inclusions in erythroid precursors on bone marrow biopsy sections. Six of the 8 patients had documented immunodeficiencies; 4 had acquired immune deficiency syndrome (AIDS), and 2 were on chemotherapy. Five of 7 patients were negative for immunoglobulin G (IgG) antiparvovirus antibodies, including all 4 with AIDS. Unlike the typical pattern in parvovirus infection, the bone marrow was hypercellular in most of the patients, and erythroid precursors were usually increased with the entire spectrum of normoblast maturation represented; abundant intranuclear inclusions were observed similar to the finding in fetuses. The inclusions were variably eosinophilic and compressed the chromatin against the nuclear membrane. In situ hybridization showed parvovirus B19 DNA in numerous erythroid precursors in all cases. The findings of erythroid maturation and abundant viral inclusions in these immunocompromised patients is consistent with the hypothesis that failure to produce effective IgG parvovirus neutralizing antibodies may lead to persistent infection through viral tolerance that allows erythroid development of infected cells past the pronormoblast stage. Identification of parvovirus inclusions in marrow biopsies and subsequent confirmation of infection by in situ hybridization can be important in the assessment of anemia in immunodeficient patients because serological studies for parvovirus B19 are frequently negative.     

Isolation, cloning, and expression of a 70-kilodalton plasminogen binding protein of Borrelia burgdorferi.

Surface receptors for plasminogen are expressed by many gram-positive and gram-negative bacteria and may play a role in the dissemination of organisms by binding plasminogen, which upon conversion to plasmin can digest extracellular matrix proteins. Two plasminogen binding proteins have been identified for Borrelia burgdorferi, outer surface protein A and a 70-kDa protein (BPBP). We purified BPBP by plasminogen affinity chromatography and obtained its amino acid sequence by Edman degradation of a tryptic digest. The gene coding for BPBP was isolated from a lambda-ZAP II genomic library with probes developed from sequenced portions of the protein. This gene was expressed in Escherichia coli; the recombinant product was seen by antibody raised against native BPBP and also bound 125I-labeled plasminogen. The experimentally derived amino acid sequences corresponded to the predicted sequence encoded by the BPBP gene. The deduced amino acid sequence for BPBP revealed significant similarity to p30, a 30-kDa protein of B. burgdorferi (54% identity and 65% similarity), to a 60-kDa protein in Borrelia coriaceae (66% identity and 80% similarity), to oligopeptide binding protein A of E. coli (34% identity and 57% similarity), and, more generally, to the periplasmic oligopeptide binding family of proteins.     

H-2b bound to egg lecithin liposomes: biochemical and functional properties.

Purified H-2b and H-2a molecules were bound to egg lecithin liposomes by a detergent dialysis procedure. Analysis of the liposomes indicated that only 30-50% of bound H-2b is oriented with the hydrophilic, antigenic portion of the molecule toward the outside of the liposome. Saturation of the liposomes occurred at a ratio of 64 molecules of egg lecithin per molecule of H-2b. Liposomes containing H-2 molecules were capable of stimulating spleen cells from primed donors to produce specific, alloreactive, cytotoxic T lymphocytes in vitro. Stimulation was dependent on adherent cells present in the responder spleen cells. Optimal stimulation occurred with highly saturated liposomes and at a ratio of 4-8 micrograms of H-2b per 8 X 10(6) responder cells.