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81.
Caveolae are involved in clathrin-independent endocytosis, transcytosis, signal transduction, and tumor suppression – all of which depend on their main constituent protein caveolin families. The periodontal Ruffini ending has been reported to develop a caveola-like structure on the cell membrane of both the axon terminals and Schwann sheaths, suggesting the existence of an axon–Schwann cell interaction in the periodontal Ruffini endings. However, little information is available concerning the functional significance of these caveolae. The present study was undertaken to examine the immunolocalization of caveolin-1, -3 (Cav-1, Cav-3) and Ca2+-ATPase in the periodontal Ruffini endings of the rat incisor. Decalcified sections of the upper jaws were processed for immunocytochemistry at the levels of light and electron microscopy. Some immunostained sections were treated with histochemistry for nonspecific cholinesterase (nChE) activity. Observations showed the periodontal Ruffini endings were immunopositive for Cav-1, but not Cav-3. Immunoreactive products for Cav-1 were confined to caveola-like structures in the cell membranes of the cytoplasmic extensions and cell bodies of the terminal Schwann cells associated with the periodontal Ruffini endings. However, the axonal membranes of the terminals did not express any Cav-1 immunoreaction. Double staining with Ca2+-ATPase and either protein gene product 9.5 (PGP 9.5) or S-100 protein disclosed the co-localization of immunoreactions in the axonal branches of the periodontal Ruffini endings, but not in the terminal Schwann cells. As Ca2+ plays an important role in mechanotransduction, these characteristic immunolocalizations show Cav-1/Ca2+-ATPase might be involved in the quick elimination of intracellular Ca2+ in mechanotransduction.  相似文献   
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A reduced incidence of graft versus host disease (GvHD) has been documented among Japanese allogeneic bone marrow transplantation (BMT) patients, as the Japanese are genetically more homogeneous than western populations. To clarify whether this ethnic difference affects the results of allogeneic peripheral blood stem cell transplantation (PBSCT), we conducted a nationwide survey to compare clinical outcomes of allogeneic PBSCT (n = 214) and BMT (n = 295) from a human leucocyte antigen-identical-related donor in Japanese patients. The cumulative incidence of grades II-IV acute GvHD was 37.4% for PBSCT and 32.0% for BMT. The cumulative incidence of extensive chronic GvHD at 1 year was significantly higher after PBSCT than BMT (42% vs. 27%; P < 0.01). The organ involvement patterns of GvHD were different between the two groups. By multivariate analyses, the incidence of chronic GvHD was significantly increased in PBSCT, whereas the stem cell source did not affect the incidence of acute GvHD, transplant-related mortality, relapse or survival. We concluded that Japanese PBSCT patients have an increased risk of chronic GvHD compared with BMT patients, but the incidence of acute GvHD was still lower than in western populations. Thus, the choice of haematopoietic stem cell source should be considered based on data for individual ethnic populations.  相似文献   
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Trends in Asthma Mortality in Japan   总被引:3,自引:0,他引:3  
Asthma mortality has been increasing in many developed countries in recent years, so we have described the epidemiological features of asthma in Japan. Data on all certified asthma deaths from 1950 to 1997 were obtained from The National Vital Statistics, published annually by the Ministry of Health and Welfare. Trends in crude and age-adjusted asthma mortality rates, as well as age-specific mortality rates, were analyzed. Age and birth cohort effects on mortality rates were also examined using multiplicative models. Between 1950 and 1980, crude asthma mortality rates steadily decreased in both sexes and began to level off thereafter. Age-adjusted mortality rates have also decreased since 1950, and showed a persistent downward trend in both sexes even in recent years. Asthma mortality rates were higher in males than in females during the entire study period. When analysis was restricted to those aged 5 to 34 years, an upward trend since 1980 was observed. The multiplicative model showed a rapidly decreasing cohort effect on mortality among those born after 1860. However, the slope increased in the cohorts born after 1950 in both sexes. The age effect increased linearly with advancing age after 50 years in both sexes. Overall asthma mortality rates have been decreasing during the past five decades in Japan, but the mortality rate has increased among the 5-34-year-old age group since 1980. The high fatality rate stemming from the overuse of beta 2-agonists may account for the mortality increase.  相似文献   
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Previous studies have found markedly elevated serum concentrations of proinflammatory cytokines in patients with Graves’ disease (GD). We investigated the role of macrophage colony-stimulating factor (M-CSF) in GD. We assayed concentrations of M-CSF in sera from 32 patients with GD (25 untreated; 7 receiving thiamazole therapy). We also studied 32 age-matched healthy subjects as controls. Relationships between serum M-CSF and both thyroid state and serum lipids were examined. Moreover, to examine the effect of thyroid hormone alone on serum M-CSF, T3 was administered orally to normal subjects. Serum concentrations of M-CSF in GD patients who were hyperthyroid were significantly increased compared with GD patients who were euthyroid (P < 0.05) and control subjects (P < 0.0001). Serum M-CSF concentrations correlated closely with T3 levels in patients (= 0.51, < 0.005). Serial measurement of five individual patients revealed that serum concentrations of M-CSF were significantly decreased (P < 0.05), reaching normal control values upon attainment of euthyroidism. Furthermore, oral T3 administered to 15 volunteers for 7 days produced significant increases in serum levels of M-CSF (< 0.05). The close correlation between serum M-CSF and serum thyroid hormone levels suggests that high circulating levels of thyroid hormones may directly or indirectly potentiate the production of M-CSF in patients with GD.  相似文献   
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Background/Purpose

Between 1988 and 2003, 38 patients underwent biliary resection for pancreaticobiliary maljunction (PBM). We reviewed the histopathologic findings for the surgically resected specimens to compare the clinical and pathologic features and assess the relationship between changes in the background biliary epithelium and the development of neoplasms.

Methods

Papillary hyperplasia (PHP) seen in the biliary epithelium of patients with PBM, was classified into grades 0–III in the gallbladder and grades 0–II in the extrahepatic bile duct, according to the extent, and was assessed for links with tumors in the same specimens.

Results

The incidence of gallbladder carcinoma was 13/21 in grades I–II, versus 0/16 in grade III, while the incidence of bile duct carcinoma was 4/20 in grade I versus 0/5 in grade II. Furthermore, these incidences for patients below age 50 years and age 50 or older were 1/18 versus 12/20, and 0/14 versus 6/17, respectively.

Conclusions

PHP of the biliary epithelium in PBM patients is an important precursor lesion, especially for gallbladder cancer, and the risk becomes greater with age, regardless of the type of pancreatobiliary junction (PBJ) and its location in the biliary tract.  相似文献   
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