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81.
The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases. 相似文献
82.
83.
J. Dawson C. Rordorf-Adam T. Geiger H. Towbin S. Kunz H. Nguyen O. Zingel D. Chaplin K. Vosbeck 《Inflammation research》1993,38(1-2):255-264
We have used our newly described mouse tissue chamber model [1], to investigate the process of IL-1 production in more detail. The inflammatory reaction in the tissue surrounding the implanted chambers was investigated histologically and by using the polymerase chain reaction (PCR). The inflammatory response included influx of leucocytes into the granuloma surrounding the tissue chamber, expression of IL-1 on macrophages present in the inflamed tissue and an increase in the mRNA coding for IL-1 and IL-6 proteins in the granuloma. The effects of three anti-inflammatory or immunosuppressive drugs, prednisolone, indomethacin and cyclosporin A, on IL-1 and PGE2 production in zymosan andBordetella-pertussis-vaccine (BPV)-challenged tissue chambers were also examined. Oral treatment with prednisolone and cyclosporin A of zymosan-challenged animals showed a dose-dependent reduction of IL-1 concentrations, but no effect of indomethacin. Both prednisolone and indomethacin dose-dependently reduced PGE2 concentrations to control levels, while cyclosporin A was effective only at the highest dose tested (100 mg/kg/day p.o.). In drug-treated BPV-challenged animals, prednisolone and cyclosporin A also showed a dose-dependent reduction of IL-1, while indomethacin was again ineffective. Prednisolone and indomethacin also dose-dependently reduced the PGE2 concentrations to control levels, whereas cyclosporin A was effective only at the highest dose tested (100 mg/kg/day p.o.).This model will be useful for investigating the mechanisms controlling the production of IL-1 from the mRNA level to the secretion of mature biologically active protein [1], and in the search for new drugs which could selectively interfere with this process. 相似文献
84.
Phan TG Nishimura S Okame M Nguyen TA Khamrin P Okitsu S Maneekarn N Ushijima H 《Journal of medical virology》2004,74(1):173-179
A total of 236 fecal specimens collected from infants and children with gastroenteritis in Maizuru city, Japan from July 2002 to June 2003, were tested for the presence of rotaviruses, noroviruses, sapoviruses, astroviruses, and adenoviruses by RT-PCR, PAGE, RPHA, and latex agglutination methods. Among diarrheal viruses detected, group A rotavirus was the most prevalent (32.2%; 76 of 236) followed by norovirus GII (21.2%; 50 of 236), group C rotavirus (10.2%; 24 of 236), adenovirus (3.8%; 9 of 236), sapovirus (2.5%; 6 of 236), astrovirus (1.3%; 3 of 236), and norovirus GI (0.8%; 2 of 236), respectively. It is noteworthy that group C rotavirus infection was apparently confined only within the period of 5 months (December 2002 through April 2003). This pattern of infection implied that the outbreak of group C rotavirus in these patients, which was the first outbreak of gastroenteritis attributed to group C rotavirus in Maizuru city. Moreover, about half (12 of 24) of group C rotavirus infected cases were confined to infants and young children less than 3 years old. Another interesting feature of the study was the demonstration of the mixed infections with group C rotavirus and group A rotavirus, as well as group C rotavirus and norovirus GII in 20.8% (5 of 24) and 8.3% (2 of 24), respectively. This is the first report of gastroenteritis associated with the mixed infections with group C rotavirus and other viral enteropathogens such as norovirus. The results indicate that group C rotavirus could infect not only older children and adults but also infants and young children under 3 years old. 相似文献
85.
Niels Fisker Court Pedersen Marianne Lange Nga Thien Tich Nguyen Kim Thien Tich Nguyen J?rgen Georgsen Peer Brehm Christensen 《Journal of clinical virology》2004,31(1):46-52
BACKGROUND: Denmark has a low incidence of acute hepatitis B (HBV) infections but the impact of an increasing number of immigrants with chronic HBV infection on HBV transmission is unknown. OBJECTIVES: To characterise individuals with chronic and acute HBV infection in a defined region and to examine the importance of different risk groups for the current HBV transmission. METHODS: During 2000-2001 all consecutive HBV infected individuals routinely diagnosed through the regional HBV serology laboratory in the County of Funen were classified according to ethnicity, presumed route of transmission and stage of infection based on clinical data mainly supplied by the requesting physician. HBV DNA was sequenced and subjected to phylogenetic analysis. RESULTS: Of 309 identified cases, 91 (29%) were classified as acute infection. HBV DNA sequencing was possible in 54 (59%) of these cases. Phylogenetic analysis showed that HBV isolated from injecting drug users (IDUs) was identical or closely related. Among acute cases acquired in Denmark 89% (74/83) were seen in IDUs (65) or in individuals presumably exposed to IDUs (nine) and phylogenetic analysis corroborated the assumption of IDU related transmission in every case with available sequence data. Among 83 ethnic Danes who acquired their HBV infection in Denmark, no new cases of transmission from immigrants were detected. CONCLUSION: Injecting drug use was the single most important factor for hepatitis B transmission in Denmark. The current Danish vaccination strategy is unable to protect IDUs from HBV infection and IDUs pose a greater risk of HBV transmission to the general population than immigrants. 相似文献
86.
Odile Launay Jean-Claude Nguyen Van Annie Buu-Hoï J. F. Acar 《Clinical microbiology and infection》1997,3(5):541-544
Objective: To report a case of typhoid fever contracted in Portugal in 1994 due to a Salmonella typhi isolate which had reduced susceptibility to fluoroquinolone (MIC 1 mg/L of ciprofloxacin) and high level resistance to nalidixic acid (MIC ≥56 mg/L).
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
87.
Ultan F. Power Hélène Plotnicky-Gilquin Thierry Huss Alain Robert Michel Trudel Stefan Ståhl Mathias Uhlén Thien Ngoc Nguyen Hans Binz 《Virology》1997,230(2):155
A subunit approach to the development of a respiratory syncytial virus (RSV) vaccine was investigated. It involved the production, inEscherichia coli,of an RSV (Long) G protein fragment (G2Na) as a C-terminal fusion partner to an albumin binding region (BB) of streptococcal protein G. G2Na incorporated amino acid residues 130–230 and was specifically recognized by murine anti-RSV-A polyclonal serum. In mice, intraperitoneal immunization with BBG2Na induced high anti-RSV-A serum ELISA titers and low to moderate neutralization activity. The immune response induced by BBG2Na demonstrated a potent protective efficacy against upper and lower respiratory tract RSV-A infection. The immunogenicity and protective efficacy of BBG2Na was maintained for at least 47 and 48 weeks, respectively, and was as potent and durable as live RSV-A administered in a similar fashion. Intramuscular immunization of cotton rats with BBG2Na protected lungs from both homologous and heterologous virus challenge. In contrast to mice, however, cotton rat nasal tracts were not protected after BBG2Na immunization. Consistent with antibody-mediated protection, virus was cleared within 24 hr from the lungs of BBG2Na-immunized mice. The anti-RSV-A antibodies induced in mice were exclusively of the IgG1 isotype and were detected in the serum, lungs, and nasal tracts. Passive transfer of these antibodies prevented acute, and eliminated chronic, RSV-A lung infection in normal and immunodeficient mice, respectively, confirming that such antibodies are important and sufficient for BBG2Na-induced pulmonary protection. Our results clearly demonstrate that BBG2Na contains an important immunogenic domain of the RSV G protein. The prokaryotic origin of this protein indicates that glycosylation of the RSV G protein is not necessary for protective efficacy. Thus, BBG2Na has potential as an RSV subunit vaccine. 相似文献
88.
A unique exonic splice enhancer mutation in a family with X-linked mental retardation and epilepsy points to a novel role of the renin receptor 总被引:6,自引:0,他引:6
Ramser J Abidi FE Burckle CA Lenski C Toriello H Wen G Lubs HA Engert S Stevenson RE Meindl A Schwartz CE Nguyen G 《Human molecular genetics》2005,14(8):1019-1027
The renin-angiotensin system (RAS) is essential for blood pressure control and water-electrolyte balance. Until the discovery of the renin receptor, renin was believed to be mainly a circulating enzyme with a unique function, the cleavage of angiotensinogen. We report a unique mutation in the renin receptor gene (ATP6AP2) present in patients with X-linked mental retardation and epilepsy (OMIM no. 300423), but absent in 1200 control X-chromosomes. A silent mutation (c.321C>T, p.D107D) residing in a putative exonic splicing enhancer site resulted in inefficient inclusion of exon 4 in 50% of renin receptor mRNA, as demonstrated by quantitative RT-PCR. Analysis of membrane associated-receptor molecular forms showed the presence of full-length and truncated proteins in the patient. Functional analysis demonstrated that the mutated receptor could bind renin and increase renin catalytic activity, similar to the wild-type receptor, but resulted in a modest and reproducible impairment of ERK1/2 activation. Thus, our findings confirm the importance of the RAS in cognitive processes and indicate a novel specific role for the renin receptor in cognitive functions and brain development. 相似文献
89.
Azevedo MS Yuan L Iosef C Chang KO Kim Y Nguyen TV Saif LJ 《Clinical and diagnostic laboratory immunology》2004,11(1):12-20
A sequential mucosal prime-boost vaccine regimen of oral attenuated (Att) human rotavirus (HRV) priming followed by intranasal (i.n.) boosting with rotavirus protein VP2 and VP6 rotavirus-like particles (2/6-VLPs) has previously been shown to be effective for induction of intestinal antibody-secreting cell (ASC) responses and protection in gnotobiotic pigs. Because serum or fecal antibody titers, but not intestinal ASC responses, can be used as potential markers of protective immunity in clinical vaccine trials, we determined the serum and intestinal antibody responses to this prime-boost rotavirus vaccine regimen and the correlations with protection. Gnotobiotic pigs were vaccinated with one of the two sequential vaccines: AttHRV orally preceding 2/6-VLP (VLP2x) vaccination (AttHRV/VLP2x) or following VLP2x vaccination (VLP2x/AttHRV) given i.n. with a mutant Escherichia coli heat-labile toxin (mLT) as adjuvant. These vaccines were also compared with three i.n. doses of VLP+mLT (VLP3x) and one and three oral doses of AttHRV (AttHRV1x and AttHRV3x, respectively). Before challenge all pigs in the AttHRV/VLP2x group seroconverted to positivity for serum immunoglobulin A (IgA) antibodies. The pigs in this group also had significantly higher (P < 0.05) intestinal IgA antibody titers pre- and postchallenge and IgG antibody titers postchallenge compared to those in the other groups. Statistical analyses of the correlations between serum IgM, IgA, IgG, and virus-neutralizing antibody titers and protection demonstrated that each of these was an indicator of protective immunity induced by the AttHRV3x and the AttHRV/VLP2x regimens. However, only IgA and not IgM or IgG antibody titers in serum were highly correlated (R2 = 0.89; P < 0.001) with the corresponding isotype antibody (IgA) titers in the intestines among all the vaccinated groups, indicating that the IgA antibody titer is probably the most reliable indicator of protection. 相似文献
90.
Expression of CD95 antigen and Bcl-2 protein in non-Hodgkin's lymphomas and Hodgkin's disease. 总被引:2,自引:1,他引:2
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P. L. Nguyen N. L. Harris J. Ritz M. J. Robertson 《The American journal of pathology》1996,148(3):847-853
CD95 (APO-1/Fas) is a member of the superfamily that includes the nerve growth factor and tumor necrosis factor receptors, OX40, CD27, CD30, and CD40. Present on a minority of resting blood lymphocytes, CD95 expression is upregulated on activated T and B lymphocytes and natural killer cells, where binding of the antigen by anti-Fas and anti-APO-1 antibodies has been shown to induce apoptosis. This CD95-mediated apoptosis is at least partially inhibited by expression of the Bcl-2 protooncogene. To evaluate possible roles of CD95 and Bcl-2 in growth regulation of lymphoid neoplasms, we studied by immunohistochemistry the expression of CD95 and Bcl-2 in 67 B- and 5 T-cell lymphomas, and 10 cases of Hodgkin's disease. In all, 29 B and 2 T cell lymphomas, and 9 cases of Hodgkin's disease expressed CD95. Compared with diffuse large B-cell and Burkitt-like lymphomas, lowgrade B-cell lymphomas more frequently expressed CD95 (52% versus 26%; P < .005). None of the B-cell small lymphocytic lymphomas or mantle cell lymphomas expressed CD95, whereas the majority of follicle center lymphomas, extranodal marginal zone B-cell lymphomas, and immunocytomas were CD95+. Of the 29 CD95+ B-cell lymphomas, only 33% of the high-grade group coexpressed Bcl-2, compared with 87% of the low-grade group (P < .04). Two of three peripheral T-cell lymphomas--including one anaplastic large cell lymphoma--expressed CD95. Staining for CD95 was seen in 9 of 10 cases of Hodgkin's disease. The infrequent expression of CD95 in high-grade B-cell lymphomas suggests an association between loss of CD95 expression/function and a more aggressive tumor grade. Whereas frequent coexpression of Bcl-2 with CD95 may protect low-grade B-cell lymphomas against CD95-mediated apoptosis, in the high-grade group such coexpression is infrequent, and other regulators besides Bcl-2 may be involved in modulating the apoptosis signal delivered by CD95. 相似文献