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11.
The disturbance of immune regulatory T cells is related to the pathogenesis of ulcerative colitis. Here we demonstrated and characterized the serum factor from ulcerative colitis patients that induced proliferation of intrathymic T cells. The factor isolated from the patient sera by a combination of gel filtration and anion-exchange chromatography induced proliferation of CD4+CD8 intrathymic T cells in the organ-cultured embryonic mouse thymus. Purification and amino acid sequence analysis of the serum factor demonstrated that the N-terminal 12 sequence was homologous to that of interleukin-7. SDS-PAGE and Western blot confirmed that purified serum factor was interleukin-7. Enzyme immunoassay demonstrated that the serum interleukin-7 concentration was significantly increased in the patients. PCR and Southern blot hybridization demonstrated that interleukin-7 mRNA expression was increased in the thymus tissues from patients but decreased in the colonic mucosa. Since interleukin-7 is a crucial cytokine for proliferation and differentiation of T cells in the thymus, the present study indicates that interleukin-7 may contribute to the disturbance of immune regulatory T cells in ulcerative colitis.  相似文献   
12.
Mice homozygous for klotho gene deletion are well established aging models as they mimic certain aspects of human senescence e.g. osteoporosis. Induced senescence may affect cellular functions and alter the histological properties of the extracellular matrices. The present study examined the histological and ultrastructural features of osteocytes and the surrounding bone matrix in klotho-deficient mice. As expected, osteoblasts showed a flattened shape with a weak immunoreactivity for alkaline phosphatase, and the bone matrix contained many empty osteocytic lacunae. The walls of both normal and empty lacunae were intensely immunopositive for osteopontin and dentin matrix protein-1, but featured an inconsistent immunoreactivity for osteocalcin and type I collagen. Not surprisingly, TUNEL-positivity, indicative of apoptosis, was found in many osteoblasts, osteocytes, and bone marrow cells of the klotho-deficient mice. In transmission electron microscopy, an amorphous matrix containing non-collagenous organic materials was recognizable around osteoblasts and in the osteocytic lacunae. Some osteoblasts on the bone surface featured these amorphous materials in vacuoles associated with their trans-Golgi network, indicating that, under klotho-deficient conditions, they synthesize and secrete the non-collagenous structures. Some osteocytes displayed pyknosis or degenerative traits. Thus, our findings provide histological evidence that klotho gene deletion influences the spatial distribution of osteocytes and the synthesis of bone matrix proteins in addition to the accelerated aging of bone cells.  相似文献   
13.
为探讨成釉细胞纤维肉瘤( A F S)间叶细胞的本质及特征, 作者采用免疫组化和电镜技术,对3例 A F S间叶细胞进行了研究,并与6例成釉细胞纤维瘤进行比较。结果显示: A F S的间叶细胞主要由成纤维细胞构成,此外尚有少许未分化间叶细胞和组织细胞, 偶见肌纤维母细胞。成纤维细胞仅表现 Vim entin 阳性。肌纤维母细胞呈 Vim entin, H H F35及 α S M A 阳性。组织细胞 P G M1 和kp1标记均阳性, 可能是炎症或免疫反应的产物。与成釉细胞纤维瘤比较, A F S间叶细胞具备较高的 P C N A 阳性标记率, 提示 A F S的增生活性较高。  相似文献   
14.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
15.
PURPOSE: Ewing's family tumors (EFTs) display the characteristic fusion gene EWS-Fli1. We have reported EWS-Fli1 may promote the cell cycle progression accompanied by the suppression of the expression of cyclin-dependent kinase inhibitor p27(kip1) in EFT cells. Here, we describe the prognostic and therapeutic relevance of p27 in EFTs. EXPERIMENTAL DESIGN: We examined tumor samples taken from 21 patients with primary EFTs for the expression of p27 protein immunohistochemically and evaluated its correlation with clinical outcome. We also investigated the usefulness of p27 as a therapeutic strategy in vitro and in vivo using p27 expression adenovirus. Finally, we examined the process of EWS-Fli1-mediated reduction of p27 expression. RESULTS: Immunohistochemical analysis showed that a low expression level of p27 protein was related to poor event-free survival in an univariate analysis and that the expression level of p27 correlated more significantly with patient survival than several clinical factors in a multivariate survival analysis. Overexpression of p27 with the adenoviral vector remarkably inhibited the cell growth in all EFT cells tested and further induced apoptosis in the wild-type p53 EFT cells. In vivo studies demonstrated a reduction in tumor growth of EFT xenograft in nude mice treated with the intratumoral injection of p27-expressing adenovirus. EWS-Fli1 did not significantly affect the p27 promoter activity and p27 mRNA levels. However, the challenge of the proteasome inhibitor caused accumulation of p27 protein in EFT cells. These data strongly suggest EWS-Fli1 might attenuate p27 protein level via activation of the proteasome-mediated degradation pathway. CONCLUSIONS: Our findings provide the first evidence of the prognostic relevance of p27 expression in EFTs. We propose p27 as a novel and powerful therapeutic factor for the molecular target therapy of EFTs.  相似文献   
16.
17.
Interstitial pneumonia (IP) is a major risk factor for lung adenocarcinoma (LADC). IP-related LADC predominantly develops in the bronchiolar metaplasia lining in honeycomb lesions. Kirsten rat sarcoma virus (KRAS) is the most common oncogene mutated in IP-related LADC. The present study examined the metaplastic epithelia in honeycomb lesions for KRAS mutations using digital droplet polymerase chain reaction (ddPCR), a sensitive method used to detect infrequent mutations. Significantly higher KRAS mutation variant allele frequencies (VAFs) were detected in the metaplastic lung epithelia from 13 patients with IP compared with those in 46 non-lesioned lung samples from patients without IP (G12V, P=0.0004, G12C, P=0.0181, and G12A, P=0.0234; Mann Whitney U test). Multivariate analyses revealed that higher KRAS G12V (logistic regression model; P=0.0133, odds ratio=7.11) and G12C (P=0.0191, odds ratio=5.81) VAFs in patients with IP were independent of confounding variables, such as smoking and age. In patients with IP, metaplastic epithelia exhibited significantly higher KRAS G12V and G12C VAFs compared with the non-lesioned counterparts (paired t-test; G12V, P=0.0158, G12C, P=0.0465). These results suggested that IP could increase KRAS mutations and supported the hypothesis that bronchiolar metaplasia could be a precursor for IP-related LADC.  相似文献   
18.
ObjectivesLaparoscopic abdominal surgery (LS) has been prevailing over open surgery (OS). However, its functional outcomes in the aging generation have not been sufficiently examined. We compared changes in physical status and earlier resumption of oral intake between LS and OS.MethodsUsing the Japanese administrative database, we matched variables affecting LS and compared them between LS and OS patients. During the 6-month period from July to December of 2006–2010, we examined the data from data from surviving patients of ≥15 year old who underwent isolated gastrectomy, colectomy, or anterior resection. Functional status was estimated by the Barthel index (BI) at admission and discharge. Outcomes were postoperative complications, BI deterioration, change in BI, and day of recommencing postoperative oral intake.ResultsWe identified 30,763 gastrectomies (laparoscopic: 7297), 31,958 colectomies (laparoscopic: 9364), and 12,545 anterior resections (laparoscopic: 4351). Variation in LS indications was observed in patient and hospital mixes. Among the paired-matched gastrectomy, colectomy, and anterior resection groups, LS was associated with fewer complications and earlier recovery of postoperative oral intake. Laparoscopic anterior resection (LAR) and colectomy were associated with less frequent BI deterioration. Longer operative time was associated with more complications, which then influenced BI deterioration in patients who underwent anterior resection.ConclusionsShorter operative time for LAR was associated with less functional deterioration than for laparoscopic gastrectomy and colectomy. Physicians should consider the appropriate indications for LS by concurrently avoiding unnecessary longer operations and their associated complications. More investment in teaching the skills necessary for LAR is recommended.  相似文献   
19.
Objective: Recent studies have reported a high prevalence of primary aldosteronism (PA) among hypertensive patients. However, few data exist regarding the prevalence of PA in the general population. Therefore, we examined the prevalence of PA in the general population including normotensive subjects. Methods: Plasma renin activity (ng/mL/hr), plasma aldosterone concentration (pg/mL) and aldosterone renin ratio (ARR) were determined in 309 subjects aged >40 years in Horimatsu and Higashi-Matsuho district, Shika-machi, Ishikawa, Japan. Results: Among them, 195 subjects (78 males, mean age: 62 ± 11 years) did not take antihypertensive agents: 113 normotensive subjects and 82 hypertensive subjects. Under these conditions, 68 subjects (13 males, age 62 ± 10 years) had an ARR >200. In 14 subjects who underwent captopril suppression test, PA was documented in 5 subjects, yielding a minimum prevalence of 2.6% in total subjects (1.8% in normotensive subjects and 3.7% in hypertensive subjects). Interestingly, females subjects demonstrated significant differences in ARR between subjects with age <50 (172 ± 105) and those with age 51–60 (388 ± 531), although there were no differences in male subjects. Conclusions: These results demonstrate that PA including normotensive subjects exists more commonly than that expected in the general population. We suggest further investigation about the cause and progression of PA associated with sex and aging.  相似文献   
20.
Aim: The epidemiology of acute hepatitis B is unknown in many countries, and the clinical features of this disease remain unclear. In this study, we used the Diagnosis Procedure Combination (DPC) database to estimate the incidence of acute hepatitis B and investigate the clinical practices for acute hepatitis B in Japan. Methods: The DPC database is a nationwide discharge abstract and administrative claims database, covering 40% of all inpatient admissions to acute care hospitals between 1 July and 31 December each year in Japan. We identified cases with a diagnosis of acute hepatitis B between 2007 and 2008. Patient characteristics, length of stay, in‐hospital mortality and total charges were determined. Clinical practice patterns were examined, including drugs used and procedures performed during hospitalization. Results: We identified 890 cases with acute hepatitis B among 5.85 million inpatients in the database. The mean age was 40.0 years old and 76% were male. The incidence of acute hepatitis B was estimated to be approximately 2100–2400/year (17–19/1 million people per year). Of 890 cases, 53 (6.0%) developed fulminant hepatitis and 36 (4.0%) died. Nucleos(t)ide analogs were prescribed for 226 cases (25.4%). Only 194 cases (21.8%) were tested for HIV status. Conclusion: It is essential to monitor the trends of this communicable and preventable disease. The establishment and distribution of appropriate clinical evidence and guidelines are vital to improve the clinical practices for acute hepatitis B.  相似文献   
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