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1.
To investigate the role of cell-mediated immunity (CMI) in glomerulonephritis (GN), we identified the infiltrating immune cells both within the glomerulus and in the interstitium. Frozen sections from 103 patients with various forms of GN: 10 with minor glomerular abnormality (MGA) as control, 10 with minimal change nephrotic syndrome (MCNS), 10 with membranous nephropathy (MN), 9 with focal glomerulosclerosis (FGS), 30 with IgA nephropathy (IgAN), 22 with acute post streptococcal glomerulonephritis (APSGN), and 2 with rapidly progressive glomerulonephritis (RPGN) were examined using monoclonal antibodies (MoAb) by indirect immunoalkaline-phosphatase labelling. In most glomerulonephritis, monocyte/M phi and helper/inducer T cells were predominantly infiltrating in the interstitium, but intraglomerular infiltration was rare, except for APSGN. This interstitial infiltration increased proportionally to the level of serum creatinine, and was most prominent in RPGN. Apparently different distribution was seen in APSGN, that is, prominent increase in total number of intra-glomerular monocyte/M phi infiltration with slightly increased T cells. The change was correlated with time after onset; namely the more leucocytic infiltration was observed when the tissue was taken earlier. These data suggest that in APSGN, monocyte/M phi accumulate in glomeruli via cell mediated immunity in addition to humoral immune mechanism resulting in glomerular hypercellularity, whereas in most chronic glomerulonephritis interstitial leucocyte infiltration, particularly helper T cells and monocyte/M phi may play an important role in the progression of glomerulonephritis.  相似文献   
2.
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity.  相似文献   
3.
The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction.  相似文献   
4.
In order to examine time trends of the prevalences of HBeAg positives among HBV carriers in Japan, we analysed data on HBeAg of HBsAg positive voluntary blood donors (23,560 males, and 8659 females) at the Osaka Red Cross Blood Centre between January 1977 and March 1984. Age-specific prevalences of HBeAg positives decreased year by year for both sexes, especially for those in their teens and twenties. The prevalences of HBeAg positives decreased with age, but at any given age it was lower for the later than for the earlier birth cohorts. Although reasons for the secular declines are unknown, the findings suggest that the prevalence of HBeAg positives among HBV carriers will continue to decrease in Japan. This, together with the immunization programme implemented this year, may lead to a future reduction in the risk of HBV related liver diseases in Japan.  相似文献   
5.
 Rhabdomyosarcoma (RMS) is occasionally found in the female genital tract, and mostly appears as one of the heterologous mesenchymal components in uterine carcinosarcoma designated as malignant mixed müllerian tumour (MMMT). We examined the biological properties of a pure rhabdomyosarcoma (RMS) cell line designated FU-MMT-3, which was newly established from a surgical specimen taken from a patient with uterine MMMT. We also evaluated c-myc and MYCN gene amplification in three RMS cell lines (including FU-MMT-3) derived from three MMMTs by Southern blot analysis. FU-MMT-3 cells were propagated continuously for 57 serial passages over a 2-year period in vitro. FU-MMT-3 was able to produce tumours demonstrating pure RMS in athymic nude mice. Cytogenetically, FU-MMT-3 showed a triploidy pattern, with complex karyotypic abnormalities including trisomy of chromosome 8. All three RMS cell lines, including FU-MMT-3, showed amplification of the c-myc gene (approximately fourfold to eightfold), while no cell lines demonstrated MYCN gene amplification. FU-MMT-3 is considered to provide a useful system for the study of the biological behaviour of RMS in MMMTs. Extra copies of chromosome 8 and c-myc gene amplification may be associated with the rhabdomyoblastic differentiation in MMMT. Received: 7 January 1997 / Accepted: 2 May 1997  相似文献   
6.
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.  相似文献   
7.
The effect of sodium 6-(2-(1-(1H)-imidazolyl)methyl-4,5-dihydrobenzo(b) thiophene)carboxylate (RS-5186), a potent and long acting thromboxane synthetase inhibitor in vitro and in vivo, on infarct size and on the infiltration of polymorphonuclear leukocytes (PMNs), was studied in a rabbit coronary artery occlusion (1 h)--reperfusion (0.5 h or 3 h) model. The infarcted region was stained with triphenyltetrazolium, and the ratio of infarcted area/left ventricular area was calculated. The infiltration of PMNs into the infarcted region was determined by measuring the PMNs specific enzyme, myeloperoxidase (MPO) activity. In the vehicle treated group, infarct size and MPO activity were increased with increased reperfusion time from 0.5 h to 3 h (infarct size: 15.3 +/- 2.7 to 25.2 +/- 3.2%; MPO activity: 255 +/- 51 to 825.3 +/- 169.4 units/g wet weight). There was also a significant correlation (r = 0.90, p less than 0.01) between the infarct size and MPO activity. In contrast, in the RS-5186 treated group (2 mg/kg i.v.), both infarct size and MPO activity did not increase with prolongation of the reperfusion period (infarct size: 12.8 +/- 5.5 to 10.3 +/- 3.6%; MPO activity: 318.8 +/- 36.7 to 381.2 +/- 72.6 units/g wet weight). In 0.5 h reperfused samples, there was no significant difference in infarct size or in MPO activity between the vehicle treated group and RS-5186 treated group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
We established a novel murine model of pharyngeal candidiasis maintaining stable yeast population and local symptoms characteristic of pharyngeal thrush. The persistent Candida-infection was prolonged by inhalation of beclomethasone dipropionate corticosteroid. The severity of infection lesions was evaluated by determining viable cell number of Candia albicans and scores representing symptomatic curd-like white patch on pharyngeal tissue. The utility of this model was shown by the disappearance of lesions and fungal cells after treatment with fluconazole (FLCZ). The model would be useful for evaluating new chemotherapeutic or immunotherapeutic approaches against pharyngeal candidiasis, as well as in pathological studies.  相似文献   
9.
A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS.  相似文献   
10.
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.  相似文献   
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