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101.
Teramoto M Kitawaki J Koshiba H Kitaoka Y Obayashi H Hasegawa G Nakamura N Yoshikawa T Matsushita M Maruya E Saji H Ohta M Honjo H 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,51(5):352-357
PROBLEM: Tumor necrosis factor (TNF)-alpha is a major cytokine involved in inflammatory and immune function. The aim of this study was to investigate whether polymorphisms at positions -1031, -863 and -857 in the TNF gene promoter region (TNFA) and TNF receptor type 2 gene (TNFR2) are responsible in part for genetic susceptibility to endometriosis. METHODS OF STUDY: TNFA and TNFR2 polymorphisms were determined in 123 patients with endometriosis and 165 fertile healthy women by the polymerase chain reaction (PCR) - preferential homoduplex formation assay and PCR-restriction fragment length polymorphism, respectively. RESULTS: The frequency of the TNFA-U01 haplotype was increased significantly in patients with endometriosis compared with controls (P = 0.045, OR = 1.45). The TNFA-U01 haplotype was strongly associated with HLA-B*0702. No difference was found in TNFR2 polymorphism between patients and controls. CONCLUSION: Our results indicated that TNFA promoter polymorphism was associated with susceptibility to endometriosis. However, this association was not independent of HLA-class I polymorphisms. 相似文献
102.
Methylation profiling of benign and malignant breast lesions and its application to cytopathology. 总被引:9,自引:0,他引:9
Robert T Pu Lauren E Laitala Patricia M Alli Mary Jo Fackler Saraswati Sukumar Douglas P Clark 《Modern pathology》2003,16(11):1095-1101
Methylation of tumor suppressor genes has been implicated in breast cancer development. However, methylation profiles of different breast lesions, subtypes of carcinoma in particular, have not been examined in detail. In this study, we use methylation-specific PCR (MSP) to generate gene methylation profiles of different breast lesions and to test the clinical utility of such profiles. We examined the methylation status of three genes, RARbeta2, RASSF1A, and cyclin D2, on 102 samples of breast tissue, from benign (n = 36), to in situ carcinoma (n = 21), to invasive carcinoma (n = 45). We found that almost all cases of invasive carcinoma (96%) contained at least one methylated gene from our panel, whereas gene methylation was less common among benign lesions (42%) and in situ carcinoma (76%). Of the three genes, cyclin D2 methylation was most specific for malignancy because only 1 of 35 benign cases was methylated at this gene (1 case was not informative). The major histologic subtypes of invasive carcinoma show similar methylation profiles in the genes examined. We next performed MSP analysis on archival breast fine-needle aspiration (FNA) biopsy samples and corresponding surgical biopsy specimens and found a high concordance between the two types of specimens. We then analyzed 17 breast FNA biopsy samples with an indeterminate diagnosis. In this setting, MSP had a high specificity (100%) and modest sensitivity (67%) for identifying malignancy. 相似文献
103.
Boursier L Farstad IN Mellembakken JR Brandtzaeg P Spencer J 《European journal of immunology》2002,32(9):2427-2436
The contribution of peritoneal B cells to the intestinal lamina propria plasma cell population is well documented in mice, but unknown in humans. We have analyzed immunoglobulin (Ig) genes of human peritoneal B cells, because such genes show distinctive characteristics in mucosal B cells, particularly highly mutated variable regions. Here, we report the characteristics of variable region genes used by IgM, IgA and IgG in peritoneal cells. We focused on the properties of IgV(H)4-34 to allow comparisons of like-with-like between different isotypes and cells from different immune compartments. We observed that the IgM genes were mostly unmutated, and that the mutated subset had less mutations than would be expected in a mucosal B cell population. Likewise, the IgV(H)4-34 genes used by IgA and IgG from peritoneal B cells had significantly lower numbers of mutations than observed in the mucosal counterparts. Other trends observed, while not reaching statistical significance, followed the trend of peripheral B cells. The peritoneal B cell population had more IgA1 than IgA2 sequences, and there was no dominance of J(H)4 in the IgA from peritoneum or spleen, in contrast to the mucosal sequences. Overall, this study suggested that human peritoneal B cell are either peripheral or mixed in origin; they are unlikely to represent an inductive compartment for the mucosal B cell system. 相似文献
104.
A Patakfalvi K Bencze G Papp S Ferenczy L Joós F Csermely M Sebestyén T Császár G Kelényi 《Acta medica Hungarica》1986,43(4):397-405
Fifteen cases of primary gastrointestinal lymphoma diagnosed over 8 years are reviewed. In the period 1980 to 1982 there was a cumulative appearance of GI lymphomas, nine out of 15 cases were diagnosed in that period. According to its localization, lymphoma occurred in 12 cases in the stomach, and in 3 in the small intestines and the colon. One case of gastric lymphoma was Hodgkin type, the others were non-Hodgkin types. The clinical symptoms were not characteristic of lymphoma. The age of the patients was, on the average, ten years lower than the mean age of carcinoma patients. Preoperative diagnosis by gastric biopsy was successful in four cases. In patients with lymphoma of the colon not subjects to surgery, colonoscopy verified the origin of lymphoma. Exact clinical classification in the majority of cases was made intraoperatively. In the non-operated cases, sonography and lymphography were performed. In general, operation was attempted, but patients in stage II, in very poor condition, were possibly not operated. The possibility and indications of the "second look" operation are discussed. Histological typing was made according to the Kiel classification. In the literature, in the most controversial question of therapy, individual consideration of the cases is recommended. Based on our experience, in devising therapy or therapeutic strategy as well as concerning prognosis, the degree of malignancy according to histological type, clinical stage and anatomical localization seem to be the most decisive factors. In exceptionally malignant cases a protocol with doxorubicine + bleomycin + teniposide and prednisolone was applied. 相似文献
105.
106.
Paolo Lionetti Jo Spencer Emma J. Breese Simon H. Murch Jacqueline Taylor Thomas T. Macdonald 《European journal of immunology》1993,23(3):664-668
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506. 相似文献
107.
Taisuke Nakao 《Developmental dynamics》1978,151(3):319-335
The cavernous body in the lamprey gill filament was studied by electron microscopy. This body lies along the outer border of the axial plate of each gill filament and freely communicates with an afferent filament artery. Two series of blood channels run alternately, passing through the cavernous body, and lead to the marginal channels in the secondary lamellae. On the other hand, narrow blood spaces left in the cavernous body lead to the blood lacunae in the axial plate (osmoregulatory region) and to those in the secondary lamellae (respiratory region). All the blood in the cavernous body is finally collected by an efferent filament artery. The cavernous body is traversed by numerous trabeculae and collagenous columns which run diagonally in the blood spaces to connect the walls of the cavernous body. All the walls of the cavernous body, including trabeculae and collagenous columns, are completely surrounded by the cytoplasmic flanges of specialized cells called here “cavernous body cells.” These cells are about 30 μm in diameter and characterized by (1) association with collagenous columns or trabeculae and also by the presence of (2) coated caveolae and vesicles, (3) vacuoles and (4) cytoplasmic granules in their cytoplasm. These cells are considered to be related to the pillar cells in origin because of their close association with collagenous columns or trabeculae. The functional significance of the cavernous body and the cavernous body cells is discussed. 相似文献
108.
Cardoso O Leitão R Figueiredo A Sousa JC Duarte A Peixe LV 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(2):93-97
Resistance to carbapenems is emerging, and it is a great problem to therapeutics. Three isolates of Pseudomonas aeruginosa from a Portuguese hospital identified in urine and sputum, in 1995, presented a high-level resistance to imipenem (> 32 mg/L). Afterward, one isolate of P. aeruginosa recovered from urine of an ambulatory patient in 1998 showed high resistance to imipenem and meropenem. The resistance to carbapenems in these strains was associated with the production of a class B beta-lactamase, as was demonstrated by imipenem hydrolysis and inhibition by EDTA. Using primers described for bla(IMP) and bla(VIM), the amplification of the latter was observed in all isolates and a VIM-2 metallo-enzyme was identified. The pulsed-field gel electrophoresis (PFGE) patterns of these isolates were indistinguishable, suggesting dissemination to the community of this VIM-2 producer. 相似文献
109.
Fordyce Wilbert E. Brockway Jo Ann Bergman James A. Spengler Daniel 《Journal of behavioral medicine》1986,9(2):127-140
Back-pain patients with onset in the preceding 1–10 days and comparable on a back examination were randomly assigned to traditional management (A regimen) and behavioral treatment methods (B regimen). Patients were compared at 6 weeks and 9–12 months on a set of Sick/Well scores derived from patient reported vocational status (V), health-care utilization (HCU), claimed impairment (CI), and pain drawings (D) and on two measures of activity level. No differences were found at 6 weeks, but at 9–12 months, A-group S's were more sick. No A/B differences were found on activity-level measures. Group A S's showed significant increases in claimed impairment from preonset to follow-up, whereas Group B S's had returned at follow-up to preonset levelsA special acknowledgment is made to Darnel Rock, M.S., now of the Department of Psychology, Vanderbilt University, for his major contributions to the organization and analysis of the data of this study. 相似文献
110.
Beatty AL Malloy JL Wright JR 《American journal of respiratory cell and molecular biology》2005,32(2):128-134
Although it is known that surfactant lipids and proteins are altered in patients with Pseudomonas aeruginosa infections, the mechanisms and implications of these alterations are not clear. In this study, the effects of P. aeruginosa on the surfactant large aggregate fraction were examined using an in vitro surface area cycling model. Large aggregates were isolated from porcine bronchoalveolar lavage fluid and incubated with supernatants from P. aeruginosa cultures (PAO1, parent strain; PAO1-A1, lasA-negative mutant; PAO1-B1, elastase-negative mutant) or purified elastase. Amounts of surfactant protein (SP)-A and SP-B, phospholipid content, and large aggregate conversion were assessed. In addition, lipid degradation was assessed by incubating a mixture of radiolabeled phospholipids with P. aeruginosa supernatants. The results demonstrated that SP-A was degraded by PAO1 and PAO1-A1 supernatants, and by purified elastase. SP-B was degraded by PAO1 and PAO1-B1 supernatants, but not by elastase. P. aeruginosa supernatants degraded phospholipids, a process inhibited by ZnCl(2). P. aeruginosa supernatants and elastase increased conversion. The data suggest that protein degradation facilitates increased conversion, and that phospholipid degradation and conversion enhance degradation of surfactant proteins. In conclusion, P. aeruginosa secretes multiple virulence factors that cooperate to result in degradation of surfactant components and alteration of large aggregate conversion. 相似文献