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81.
Jeong HJ Sung SH Hong SW Moon JI Kim SI Kim YS Park K 《Virchows Archiv : an international journal of pathology》2000,437(1):69-73
The distribution pattern of extracellular matrix (ECM) components in transplant glomerulopathy was studied in relation to
light microscopic features, actin expression of mesangial cells, and intraglomerular inflammatory cells. Nine cases of mild
(group I) and nine cases of severe (group II) transplant glomerulopathy were stained with antisera against fibronectin (FN),
tenascin (TN), collagen types III and IV, smooth muscle actin, CD45RO, CD68, and Ki-67 antigen. The composition of ECM was
similar in the two groups. The expanded mesangium was diffusely stained by type-IV collagen, FN and TN, and focally and weakly
stained by type-III collagen and smooth muscle actin. Type-IV collagen was linearly stained along the capillary walls, imparting
a double-contour feature, whereas FN and TN showed granular staining along the capillary walls. CD68 positive cells were increased
in severe transplant glomerulopathy, but this increase was not related to ECM deposition. These findings suggest that increased
glomerular deposition of normal and abnormal ECM components participate in the evolution of transplant glomerulopathy.
Received: 5 October 1999 / Accepted: 17 January 2000 相似文献
82.
Jang WJ Kim JH Choi YJ Jung KD Kim YG Lee SH Choi MS Kim IS Walker DH Park KH 《Journal of clinical microbiology》2004,42(5):2310-2313
To investigate the prevalence of spotted fever group rickettsioses in Korea, a serosurvey of Japanese spotted fever rickettsiosis in patients with acute febrile illness was conducted with an indirect immunofluorescence assay. Overall, 19.88% of the patients were found to have polyvalent antibody against Rickettsia japonica. This study is the first documentation of spotted fever group rickettsiosis in Korea. 相似文献
83.
In this study we investigate the expression pattern of mucin genes in the human testis and evaluate the relationship between the expression of mucin genes and impaired spermatogenesis in the human testis. Thirty human testis tissues were collected from patients undergoing diagnostic testicular biopsy to investigate the cause of infertility. One part of the tissue underwent histological observation, and the other part of the tissue was subjected to semiquantitative RT-PCR of mucin genes, that is, mucin1, 2, 3, 4, and 9. The relative amount of mucin mRNAs was calculated by densitometry using glyceraldehydes-3-phosphate dehydrogenase (GAPDH) as an internal control. The samples were histologically diagnosed as either obstructive azoospermia with normal spermatogenesis (n = 13) or non-obstructive azoospermia with impaired spermatogenesis (n = 17). In the human testis with normal spermatogenesis, mRNA expression of mucin1, 9, 13 and GAPDH were found, but RT-PCR products of mucin 2, 3 and 4 were not detected. In the testis with impaired spermatogenesis, however, RT-PCR product of mucin1 was not found. There was no difference in the other mucin mRNA expression patterns between the testis with either normal or impaired spermatogenesis. To our knowledge, this study is the first that has detected the mRNA of mucin9 and 13 in human testis. This study also shows that mucin1 expression might be closely related to spermatogenesis. Our findings should be substantiated by more direct evidence, such as mucin protein expression and localization. 相似文献
84.
Santamaria J Pujol M Orteu N Solanas A Cardenal C Santacruz P Chimeno E Moon P 《Sleep》2000,23(3):333-339
STUDY OBJECTIVES: To measure the sleep spindle characteristics in patients with unilateral thalamic stroke. DESIGN: A prospective study of patients with thalamic stroke and age-matched healthy controls. SETTING: Department of Neurology of a University Hospital. PARTICIPANTS: Thirteen patients (mean age: 67 years, SD: 13,44) with an isolated, unilateral acute thalamic stroke and 18 healthy age-matched volunteers. INTERVENTIONS: A polysomnogram recording from 14 scalp EEG electrodes performed during 2 consecutive nights, the second or third week after the stroke. Only the sleep of the second night was analyzed. MEASUREMENTS AND RESULTS: Sleep spindles were counted during two separate 10-minute epochs of stage II. Spindles appearing synchronously in both sides with similar amplitude were called "bilateral." Spindles with twice the amplitude in one side than the other were "right" or "left-side predominant". There were 8 patients with posterolateral, 3 with global and 2 with anterior lesions. Eight were right and 5 left-sided. The number of spindles was similar in patients (39.8 +/- 23.4 in 20 minutes) than controls (26.07 +/- 29.07; p=0.173). Spindles with a centroparietal (34%) and centroparieto-occipital localization (22%) were the most frequent. In controls approximately 66% of the spindles had a bilateral and symmetric distribution over the scalp, 23% of the spindles were predominantly left-sided and 5% were predominantly right-sided. In patients, bilateral spindles decreased (p<0.0001) but asymmetric spindles did not change. CONCLUSION: Unilateral acute thalamic stroke does not decrease sleep spindles ipsilaterally; rather, it seems to produce a bilateral diminution in their number. 相似文献
85.
Histochemical, immunohistochemical and ultrastructural studies were performed on cases of hepatocellular carcinoma (HCC) with pale bodies (PB). HCC containing PBs was observed in 3 (5.5%) of 55 consecutively resected HCC cases. Histologically, a large number of hepatocytes displayed pale or eosinophilic staining of the cytoplasm, resulting in ground-glass appearance. They were aggregated in nodular pattern, or diffusely intermixed with other malignant hepatocytes. PBs were negative for periodic-acid Schiff and Masson's trichrome staining. The inclusions showed a strong positive reaction for fibrinogen and some of them were weakly positive for albumin but negative for hepatitis B surface antigen, hepatitis B core antigen, alpha-fetoprotein and alpha-1-antitrypsin. Ultrastructurally, PBs were membrane-bound and contained granular materials of moderate electron density, and were closely related to dilated rough endoplasmic reticulum. These findings support that PBs are secretory fibrinogen accumulated in cystic ER and that such intracellular accumulation possibly reflects a defective transport of fibrinogen. 相似文献
86.
Multilaboratory Evaluation of a Viability Assay for Measurement of Opsonophagocytic Antibodies Specific to the Capsular Polysaccharides of Streptococcus pneumoniae
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Sandra Romero-Steiner Carl Frasch Nelydia Concepcion David Goldblatt Helena Kyhty Merja Vkevinen Craig Laferriere Dominique Wauters Moon H. Nahm Mark F. Schinsky Brian D. Plikaytis George M. Carlone 《Clinical and Vaccine Immunology : CVI》2003,10(6):1019-1024
Opsonophagocytosis is a correlate of protection that measures the functional activity of vaccine-induced antibodies. A standardized opsonophagocytosis assay (OPA) should be used as part of the evaluation of current and future pneumococcal (Pnc) polysaccharide (Ps)-based vaccines. We enrolled five laboratories to evaluate a previously standardized viability OPA. Each laboratory was provided with a detailed OPA protocol, seven target Pnc strains (serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F), two quality control sera and 12 paired sera (blinded) from adult donors who received one dose of the 23-valent Pnc Ps vaccine. Laboratories sent their results to the Centers for Disease Control and Prevention for analysis. Sera were tested in duplicate (single run), and the results were averaged to yield a single OPA titer (≥50% killing) for each serum sample. The percentage of sera within one or two dilutions of the calculated median OPA titer was determined for each laboratory and for each serotype. In general, laboratories were capable of detecting OPA titers within one or two dilutions of the median for at least 75 and 88%, respectively, of the sera tested. The level of agreement with the median OPA titers varied depending on the participating laboratory (overall agreement = 0.8 [99% confidence interval = 0.75 to 0.85]). All OPA median titers reported for quality control sera were within one dilution of the expected titer. We conclude that this OPA can be done in multiple laboratories with a high degree of interlaboratory reproducibility. 相似文献
87.
Superantigen peptide antagonists failed to block T-cell activation and cytokine production as well as toxic shock induced by staphylococcal enterotoxin B (SEB) in HLA class II transgenic mice. They also failed to inhibit the binding of SEB to HLA class II molecules as well as activation of human T lymphocytes in vitro. 相似文献
88.
Kang BS Chung TW Moon JY Lim JK Shon YH Nam KS Kim DS Jeon BH Kim CH 《Immunopharmacology and immunotoxicology》2004,26(3):355-372
Contribution of cytotoxic T lymphocytes (CTL) to experimental autoimmune thyroiditis (EAT) was well defined (Speidel et al., Eur. J. Immunol. 1997, 27, 2391-2399, Ref. 7). The native porcine thyroglobulin (pTg) showed high sensitivity to endo-o-N-acetylglucosaminidase F (Endo F) and its molecular weights, corresponding to about 330 kDa as a monomer and 660 kDa as a dimer, were reduced to smaller molecular weight forms by Endo F and trifluoromethanesulfonic acid (TMSF). Deglycosylated porcine Tg (dgpTg) and native pTg were injected i.v. into CBA/J mice, without the aid of adjuvants. Both lymphocytic infiltrations of the thyroid glands and levels of Tg-specific CTL were similar to those found in conventional EAT induced by Tg and adjuvants. In contrast, proliferative responses in native pTg and dgpTg-injected mice could not be detected, and titers of antibodies to pTg and dgpTg were 20 times and 30 times lower than that of pTg and adjuvants, respectively. The EAT-inducer CTL belonged to the CD8+ cell subset and exerted their thyroiditogenic potential through release of IFN-gamma. It was concluded that dgpTg-induced EAT is mediated by type 1 cytotoxic T cells (Tcl). Also, results that EAT induction of the glycosylated pTg (gpTg) was much lower than that of dgpTg, suggested that the abberant and incomplete glycosylation of the thyroglobulin is responsible for the induction of autoimmune thyroiditis. 相似文献
89.
Nuclear translocation of survivin in hepatocellular carcinoma: a key to cancer cell growth? 总被引:13,自引:0,他引:13
Survivin is a recently described anti-apoptosis protein and regulator of cell division. Its expression and localization in hepatocellular carcinoma (HCC) and in normal liver tissue has not been fully elucidated. We examined the expression of survivin, Fas, proliferating cell nuclear antigen (PCNA), and apoptosis in 47 specimens of hepatocellular carcinoma (HCC) and surrounding nonmalignant hepatic tissues. To further determine the relationship between survivin expression and cell proliferation and apoptosis, we performed double immunostaining for survivin and PCNA TUNEL staining in the same HCC specimens. Positive immunostaining for survivin was present in 35 of 47 (74%) HCCs. Twenty-two of 35 survivin-positive HCCs (63%) showed punctate nuclear staining in HCC cells, and the remaining 13 showed predominant cytoplasmic staining. In contrast, nonmalignant hepatocytes showed only cytoplasmic staining. HCC cells had significantly higher PCNA-labeling and apoptotic indices compared with the case of nonmalignant hepatic tissue (P<0.001). Furthermore, nucleus-positive HCC specimens for survivin showed the highest PCNA labeling index. The nuclear localization of survivin in HCC cells correlated with tumor cell de-differentiation with the exception of the HepG2 cell line. Survivin expression was inversely associated with apoptosis and was strongly associated with Fas expression (P=0.01). All 4 HCC cell lines examined showed survivin expression and punctate nuclear localization. Our results indicate that survivin is localized to the cytoplasm in quiescent nonmalignant liver cells to suppress apoptosis and translocates into the nucleus in HCC cells. In conclusion, translocation of survivin from the cytoplasm to the nucleus may constitute an important regulatory mechanism for cell proliferation and differentiation in HCC. 相似文献
90.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis. 相似文献