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31.
32.
SCG10 is a nerve growth factor (NGF)-inducible, neuron-specific protein whose expression is tightly correlated with axonal and/or dendritic growth. We have recently shown that the mRNA encoding SCG10 is expressed at significant levels in certain subsets of neurons in the adult rat brain, while its expression is undetectable or negligible in other non-neuronal tissues. Here we show that regional SCG10 mRNA expression in the adult mouse brain is comparable to that in the rat, however, in the hippocampus its expression profile is distinct. In the mouse, SCG10 mRNA is expressed at high levels in pyramidal cells of CA3–CA4 sub-fields of Ammon's horn and at low levels in the CA1–CA2 sub-fields, while it is found rather uniformly throughout the pyramidal cell layer of the rat hippocampus. SCG10 mRNA is not detectable in the dentate gyrus of the mouse hippocampus, although it is expressed in the rat dentate gyrus. Comparison with other mRNAs encoding neuronal growth-associated proteins (nGAPs) such as GAP-43, MAP2, α1-tubulin and stathmin suggests that dentate granule cells express a different repertoire of neuronal growth-associated genes in mouse and rat.  相似文献   
33.
To investigate the effects of polymorphisms in the ATP-binding cassette transporter A1 (ABCA1) gene on the high-density lipoprotein cholesterol (HDL-C) level and the incidence of myocardial infarction (MI), we performed association studies. Sequence analysis identified 14 polymorphisms in the promoter region of ABCA1. After considering linkage disequilibrium, three polymorphisms in the promoter region and 11 polymorphisms from the JSNP database were determined in 1,880 subjects recruited from the Suita Study, representing the general population in Japan. We evaluated the association between the ABCA1 genotype and HDL-C level adjusted not only for standard factors, but also for genetic factors including ApoA1 and ApoE genotypes. Of the 14 polymorphisms tested, the G(–273)C (P=0.0074), C(–297)T (P=0.0195), and IMS-JST071749 (P=0.0093) polymorphisms were significantly associated with the HDL-C level in the Suita population. We could reconfirm that the G(–273)C genotype was influential in another set of subjects (P=0.0310, n=743). However, the distribution of the ABCA1 G(–273)C genotype in subjects with MI (n=598) was not different from that in the control population (n=801). These results indicate that ABCA1 G(–273)C has a significant effect on the HDL-C level in the general Japanese population, but not on the incidence of MI.  相似文献   
34.
Lymphangioma rarely presents as a solitary pulmonary lesion. We encountered a case of solitary cystic lymphangioma and present its clinicopathologic and immunohistochemical findings. A 2-month-old boy was referred to the hospital after developing a persistent cough. Chest X-ray showed a large cyst in the right lung. Under the preoperative diagnosis of bronchogenic cyst, he underwent right lower lobectomy at the age of 11 months. The resected specimen contained a 5.5-cm septate cystic lesion. Microscopically, the lesion consisted of a large cystic space and interconnected slit-like spaces surrounding bronchovascular islands. The cyst was lined by a monolayer of flat cells with focal multinucleated giant cells. Immunohistochemically, the cells lining the cystic lesion were positive for D2-40, Prox1, CD34, and CD31, and weakly positive for VEGFR-3, but were negative for AE1/3, HMB45, VEGF-A, VFGF-C, VEGFR-1. Differential diagnoses included lobar or interstitial emphysema, bronchogenic cyst, congenital pulmonary airway malformation and alveolar adenoma. D2-40 and Prox1 were useful in differentiation and in determining the extent of the lesion. A review of the literature found only 15 cases of solitary pulmonary lymphangioma. In younger patients, the lesions tend to occupy more of the lung. Focal giant cell reaction has not been described in the reported papers.  相似文献   
35.
Galectin-9 (Gal-9) ameliorates autoimmune reactions by suppressing Th17 cells while augmenting Foxp3+ regulatory T cells (Tregs). However, the exact mechanism of Gal-9-mediated immune modulation has been elusive. In a MOG-induced experimental allergic encephalomyelitis model using Gal-9−/− mice, we observed exacerbated inflammation and an increase in IL-17-producing Th17 cells balanced by a decrease in Foxp3+ Tregs. During in vitro Th17 skewing using TGF-β1 and IL-6, exogenous Gal-9 suppressed Th17 cell development and expanded Foxp3+ Tregs from naïve CD4 T cells in an IL-2-dependent manner. Although Gal-9 induced cell death in Tim3-expressing differentiated Th17 cells, Gal-9 suppressed Th17 development in a Tim-3-independent. Benzyl-α-GalNAc (an O-glycan biosynthesis inhibitor), but not swainsonine (a complex-type N-glycan biosynthesis inhibitor) abrogated Gal-9-mediated inhibition of Th17 development indicating that there is a linkage between Gal-9 and an unidentified glycoprotein(s) with O-linked β-galactosides that suppress Th17 development.  相似文献   
36.
Mori N  Mori M 《Medical hypotheses》2011,77(6):996-999
Aging is inevitable to all multi-cellular organisms, and each organism has its own lifespan. The species-specific lifespan seems determined genetically; however little is known about how the lifespan determined. During the last decades accumulative evidence indicates that there is certainly a set of genes that are involved in the lifespan determination. Among those dozens of genes, the Shc gene encoding a phosphotyrosine signal adaptor is of potential interests in mammalian aging and/or longevity determination. Shc is merely one form of a gene family, and accumulative evidence demonstrates the presence of additional Shc homologues that are strongly expressed in the nervous system. We hypothesize that lifespan is regulated primarily by the nervous system and/or brain, and neurally expressed Shc homologues play pivotal roles in relation to the evolution of longevity with quality of life. We discuss herein the recent progress of our understanding of the neuronally expressed Shc genes in comparision with p66-Shc as a candidate for the evolution of long life with higher quality of life in mammals.  相似文献   
37.
Ultrastructure of human pheochromocytoma cells cultured for long periods   总被引:1,自引:0,他引:1  
We conducted ultrastructural analysis of human pheochromocytoma (PC) cells maintained in primary culture for about 10 months. The cells were first isolated by the enzymatic treatment of a surgically resected tissue specimen obtained from a 37-year-old man with PC, a condition which is characterized by elevated blood levels of adrenaline and noradrenaline. It was found that noradrenaline production in the medium continued until the 90th day of culture (1330 pg/ml). The production level decreased to 20 pg/ml on the 180th day, and to 18 pg/ml on the 300th day. Examination under a transmission electron microscope (TEM) at 4 weeks of culture revealed electron-dense granules (about 200 nm in size and, presumably, rich in catecholamines), which were also observed in the tumor cells from the original PC tissue. Neurite-like processes grew at around 1 week of culture, and were still maintained at 6 months of culture. But, after 6 months of culture, the neurite-like processes contained a rosary-like elevated structure, which was suggestive of cell degeneration, as determined by a plasma polymerization replica method and observed with a scanning electron microscope. When cells were examined under the TEM, fewer electron-dense granules were observed in the cell bodies, with more numerous lipofuscin-like granules and filaments. Thus, electron-dense granules, which, presumably, contain catecholamines, were seen in a long-term culture of human PC cells. These granules decreased in number in parallel with the decrease in catecholamine levels in the culture.  相似文献   
38.

Background

Depression is a major risk factor for suicide, but few studies have examined psychosocial risk factors for suicide in clinical patients with depression. The purpose of this study was to investigate psychosocial factors which could be associated with suicidal ideation in clinical patients with depression including: sick-leave, help-seeking behavior, and reluctance to admit mental health problems.

Methods

A multi-center cross-sectional survey using self-report questionnaire was conducted at 54 outpatient psychiatric clinics in Tokyo in 2012. Adult outpatients who were diagnosed by psychiatrists as mood disorders (F30–F39) in the International Classification of Diseases-10 (ICD-10) were included in the study. Those who met the criteria for current hypomanic or manic episode were excluded from the study.

Results

A total of 189 patients with depression participated in the survey. Multivariable logistic regression analysis showed that taking sick-leave and having sought help from family were associated with decreased odds of current suicidal ideation. Moderate or more severe depression was associated with increased odds of suicidal ideation, and reluctance to admit own mental health problem tended to increase odds of suicidal ideation.

Limitations

Living status and suicidal ideation before consultation with psychiatrist were not investigated. Severity of suicidal ideation and comorbid psychiatric disorders were not assessed.

Conclusions

Importance of treatment of more severe depression for suicide prevention was confirmed. Industrial health staffs should consider the possibility of positive effect of taking sick-leave when they see employees with depression. Promoting help-seeking for family and reducing stigma of mental illness may be effective for suicide prevention.  相似文献   
39.
The effects of galectin-9 on a mouse collagen-induced arthritis (CIA) model were assessed to clarify whether galectin-9 suppresses CIA by regulating T cell immune responses. Galectin-9 suppressed CIA in a dose-dependent manner, and such suppression was observed even when treatment was started on 7 days after the booster, indicating its preventive and therapeutic effects. Galectin-9 induced the decreased levels of pro-inflammatory cytokines, IL-17, IL-12, and IFNgamma in the joint. Galectin-9 induced the decreased number of CD4(+) TIM-3(+) T cells in peripheral blood. Galectin-9-deficient mice became susceptible to CIA may be by increased number of CD4(+) TIM-3(+) T cells and decreased number of Treg cells. We further found that galectin-9 induces differentiation of naive T cells to Treg cells, and it suppresses differentiation to Th17 cells in vitro. The present results suggested that galectin-9 ameliorates CIA by suppressing the generation of Th17, promoting the induction of regulatory T cells.  相似文献   
40.
In order to evaluate the contribution of FBN1, FBN2, TGFBR1, and TGFBR2 mutations to the Marfan syndrome (MFS) phenotype, the four genes were analyzed by direct sequencing in 49 patients with MFS or suspected MFS as a cohort study. A total of 27 FBN1 mutations (22 novel) in 27 patients (55%, 27/49), 1 novel TGFBR1 mutation in 1 (2%, 1/49), and 2 recurrent TGFBR2 mutations in 2 (4%, 2/49) were identified. No FBN2 mutation was found. Three patients with either TGFBR1 or TGFBR2 abnormality did not fulfill the Ghent criteria, but expressed some overlapping features of MFS and Loeys-Dietz syndrome (LDS). In the remaining 19 patients, either of the genes did not show any abnormalities. This study indicated that FBN1 mutations were predominant in MFS but TGFBRs defects may account for approximately 5-10% of patients with the syndrome.  相似文献   
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