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81.
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. 下载免费PDF全文
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. 相似文献
82.
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. 相似文献
83.
T W Huber S Storms P Young L E Phillips T E Rogers D G Moore R P Williams 《Journal of clinical microbiology》1983,17(3):405-409
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. 相似文献
84.
Crook TW Rogers BB McFarland RD Kroft SH Muretto P Hernandez JA Latimer MJ McKenna RW 《Human pathology》2000,31(2):161-168
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. 相似文献
85.
Isolation, cloning, and expression of a 70-kilodalton plasminogen binding protein of Borrelia burgdorferi. 下载免费PDF全文
L T Hu S D Pratt G Perides L Katz R A Rogers M S Klempner 《Infection and immunity》1997,65(12):4989-4995
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. 相似文献
86.
M J Rogers 《Clinical and experimental immunology》1982,48(3):561-573
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. 相似文献
87.
88.
The effect of dietary supplementation with n-3 polyunsaturated fatty acids on the synthesis of interleukin-1 and tumor necrosis factor by mononuclear cells 总被引:48,自引:0,他引:48
S Endres R Ghorbani V E Kelley K Georgilis G Lonnemann J W van der Meer J G Cannon T S Rogers M S Klempner P C Weber 《The New England journal of medicine》1989,320(5):265-271
We examined whether the synthesis of interleukin-1 or tumor necrosis factor, two cytokines with potent inflammatory activities, is influenced by dietary supplementation with n-3 fatty acids. Nine healthy volunteers added 18 g of fish-oil concentrate per day to their normal Western diet for six weeks. We used a radioimmunoassay to measure interleukin-1 (IL-1 beta and IL-1 alpha) and tumor necrosis factor produced in vitro by stimulated peripheral-blood mononuclear cells. With endotoxin as a stimulus, the synthesis of IL-1 beta was suppressed from 7.4 +/- 0.9 ng per milliliter at base line to 4.2 +/- 0.5 ng per milliliter after six weeks of supplementation (43 percent decrease; P = 0.048). Ten weeks after the end of n-3 supplementation, we observed a further decrease to 2.9 +/- 0.5 ng per milliliter (61 percent decrease; P = 0.005). The production of IL-1 alpha and tumor necrosis factor responded in a similar manner. Twenty weeks after the end of supplementation, the production of IL-1 beta, IL-1 alpha, and tumor necrosis factor had returned to the presupplement level. The decreased production of interleukin-1 and tumor necrosis factor was accompanied by a decreased ratio of arachidonic acid to eicosapentaenoic acid in the membrane phospholipids of mononuclear cells. We conclude that the synthesis of IL-1 beta, IL-1 alpha, and tumor necrosis factor can be suppressed by dietary supplementation with long-chain n-3 fatty acids. The reported antiinflammatory effect of these n-3 fatty acids may be mediated in part by their inhibitory effect on the production of interleukin-1 and tumor necrosis factor. 相似文献
89.
IgD production and other lymphocyte functions in HIV infection: immaturity and activation of B cells at different clinical stages. 下载免费PDF全文
T and B cell function, in particular IgD production in vitro, were studied across the spectrum of HIV infection in homosexual men and compared with seronegative homosexual and heterosexual male controls. Proliferation to phytohaemagglutinin (PHA) was reduced most strikingly in symptomatic HIV infection; it was also impaired in HIV seronegative homosexual men and there was no difference between these and asymptomatic HIV seropositives or those with persistent generalized lymphadenopathy (PGL). Spontaneous IgG and IgM production were increased in patients with PGL and Kaposi's sarcoma; pokeweed mitogen (PWM)-induced production of IgG and IgM was reduced in all HIV infected subjects. Spontaneous production of IgD was highest in asymptomatic HIV infection, with raised values also seen in PGL and AIDS with opportunist infection; IgD production was suppressed by PWM in the same groups. These data indicate an increase in circulating immature B cells. Markers of B cell immaturity and polyclonal activation are apparent to differing degrees at different stages of HIV infection. 相似文献
90.
Immunological analysis of the zinc-binding peptides of surface metalloproteinase (gp63) of Leishmania major. 下载免费PDF全文
The surface metalloproteinase, gp63, is highly conserved and immunogenic. A peptide spanning the zinc-binding region of the molecule is immunogenic and can induce protective immunity in mice against Leishmania major infection. We report here that the minimum length of the immunogenic peptide in this region is a heptapeptide, VVTHEMA, corresponding to residues 161-167. Optimal immunogenicity is conferred by a decapeptide, LVTVVTHEMA, corresponding to residues 158 to 167, where H and E are consensus zinc-binding residues. These two residues determine the specificity of the peptide. The next two residues, M and A are necessary for the immunogenicity of the peptide. These results suggest that the zinc-binding residues are recognized by the T-cell receptor complex, while the two adjacent residues are involved in the peptide presentation by the major histocompatibility complex (MHC) molecule. 相似文献