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101.
Background/Purpose. An aggressive approach is required to resect advanced carcinoma of the gallbladder. Therefore, an extended surgical procedure often brings about a poor surgical outcome. To test whether an aggressive surgical treatment can improve the survival rate for primary advanced carcinoma of the gallbladder, 59 patients with stage IV primary gallbladder carcinoma were studied. Methods. Patients were divided into three treatment groups for the survival analysis: group A (resectional surgery, n = 29), group B (low-dose cis-diamminedichloroplatinum-II and 5-fluorouracil therapy, n = 10), and group C (exploratory laparotomy, other treatment modalities, or no treatment, n = 20). Results. The prognosis of group A patients was significantly better than that of group B (P = 0.018) or group C (P = 0.0009). Furthermore, group A patients were divided into subgroups. The prognosis of patients resected with no distant metastasis (group A1) was significantly better than that of patients resected with distant metastases of the distant lymph nodes and the liver (group A2) (P = 0.0004). Also, there was no significant difference in the survival rate between the patients resected with distant metastasis (group A2) and chemotherapy cases (group B). Conclusions. These results indicated that radical surgery should be performed for patients with no distant metastasis, and that chemotherapy might be a useful alternative treatment for patients with distant metastasis in advanced carcinoma of the gallbladder.  相似文献   
102.
Vascular calcification is a pathological calcification process. Its pathogenesis involves active mineralization by chondrogenic and osteogenic cells. Since cartilaginous metaplasia has been found in several vascular diseases, this process may represent one of vascular remodeling in response to vascular injury. Endochondral ossification following cartilaginous metaplasia play an important role in the progression of vascular calcification.  相似文献   
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Thrombomodulin (TM), a thrombin receptor expressed on the endothelial surface, is known to play an important role in the anti-thrombogenic system in vivo. In this study, we examined the effects of 3 single-nucleotide polymorphisms (SNPs) in the TM gene (G-33A, C1418T and C1922T) on the development of myocardial infarction (MI) in Koreans. We found that G-33A was a common SNP (the minor allele frequency was 0.09) in Koreans. Eighty-five MI patients who had received coronary angiography were enrolled and were divided into 3 groups according to the number of coronary arteries in which stenosis was found angiographically (1-vessel disease (1VD) to 3-vessel disease (3VD)). The criterion of coronary stenosis was 50% or more stenosis on angiography. In addition, 102 controls (CONT) who had no significant stenosis were employed. The number of AA/GA genotypes of G-33A was found to be significantly greater in the 1VD than in the CONT (p=0.004 by chi2-test) while no significant difference was found between the multivessel disease (2-3VD) and the CONT. Multiple logistic analysis showed that G-33A was an independent risk factor for the 1VD with an odds ratio of 4.63 (95% confidence interval; 1.62-13.3). C1418T and C1922T were both in linkage disequilibrium with G-33A; however, they were not independent risks for either the 1VD or the 2-3VD. A reporter gene assay showed that G-33A had a significant effect on the TM promoter activity. These results indicated that G-33A polymorphism in TM might be a genetic risk factor for myocardial infarction.  相似文献   
106.
Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ER-α), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-α and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ER-α agonist. Studies employing ER-α–null or ER-β–null mice, ER-α loss-of-function mutant rats, or siRNA demonstrated that ER-α is necessary for E2 to upregulate RV apelin. E2 and ER-α increased BMPR2 in pulmonary hypertension RVs and in isolated RV cardiomyocytes, associated with ER-α binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to exert RV-protective effects. E2 or ER-α agonist rescued monocrotaline pulmonary hypertension and restored RV apelin and BMPR2. We identified what we believe to be a novel cardioprotective E2/ER-α/BMPR2/apelin axis in the RV. Harnessing this axis may lead to novel RV-targeted therapies for PAH patients of either sex.  相似文献   
107.
The cell-cycle status of hematopoietic stem and progenitor cells (HSPCs) becomes activated following chemotherapy-induced stress, promoting bone marrow (BM) regeneration; however, the underlying molecular mechanism remains elusive. Here we show that BM-resident group 2 innate lymphoid cells (ILC2s) support the recovery of HSPCs from 5-fluorouracil (5-FU)–induced stress by secreting granulocyte-macrophage colony-stimulating factor (GM-CSF). Mechanistically, IL-33 released from chemo-sensitive B cell progenitors activates MyD88-mediated secretion of GM-CSF in ILC2, suggesting the existence of a B cell–ILC2 axis for maintaining hematopoietic homeostasis. GM-CSF knockout mice treated with 5-FU showed severe loss of myeloid lineage cells, causing lethality, which was rescued by transferring BM ILC2s from wild-type mice. Further, the adoptive transfer of ILC2s to 5-FU–treated mice accelerates hematopoietic recovery, while the reduction of ILC2s results in the opposite effect. Thus, ILC2s may function by “sensing” the damaged BM spaces and subsequently support hematopoietic recovery under stress conditions.  相似文献   
108.
Activation of EphB receptors by ephrinB (efnB) ligands on neuronal cell surface regulates important functions, including neurite outgrowth, axonal guidance, and synaptic plasticity. Here, we show that efnB rescues primary cortical neuronal cultures from necrotic cell death induced by glutamate excitotoxicity and that this function depends on EphB receptors. Importantly, the neuroprotective function of the efnB/EphB system depends on presenilin 1 (PS1), a protein that plays crucial roles in Alzheimer's disease (AD) neurodegeneration. Furthermore, absence of one PS1 allele results in significantly decreased neuroprotection, indicating that both PS1 alleles are necessary for full expression of the neuroprotective activity of the efnB/EphB system. We also show that the ability of brain-derived neurotrophic factor (BDNF) to protect neuronal cultures from glutamate-induced cell death depends on PS1. Neuroprotective functions of both efnB and BDNF, however, were independent of γ-secretase activity. Absence of PS1 decreases cell surface expression of neuronal TrkB and EphB2 without affecting total cellular levels of the receptors. Furthermore, PS1-knockout neurons show defective ligand-dependent internalization and decreased ligand-induced degradation of TrkB and Eph receptors. Our data show that PS1 mediates the neuroprotective activities of efnB and BDNF against excitotoxicity and regulates surface expression and ligand-induced metabolism of their cognate receptors. Together, our observations indicate that PS1 promotes neuronal survival by regulating neuroprotective functions of ligand-receptor systems.  相似文献   
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We report a case of rhabdoid tumor predisposition syndrome with a renal tumor developing 10 years after a brain tumor, which demonstrated an unexpectedly favorable outcome. A 2-year-old boy underwent gross total resection of a brain tumor located in the fourth ventricle, and received adjuvant chemotherapy and radiotherapy. At the age of 11 years, a renal tumor was found and nephrectomy was performed. He is currently alive without evidence of disease over 2 years without postoperative therapy. Histologically, rhabdoid cells were observed in both brain and renal tumors. Loss of SMARCB1 (also known as INI1) expression was found in the nucleus of both tumor cells. Genetic testing revealed pathogenic variants of SMARCB1 exon 5 in the renal tumor and SMARCB1 exon 9 in the brain tumor. In addition, heterozygous deletion of 22q11.21-q11.23 containing the SMARCB1 locus was shared by both tumors and this deletion was identified in normal peripheral blood. Considering the histopathological and genetic findings, our case was considered to be rhabdoid tumor predisposition syndrome with atypical teratoid/rhabdoid tumor and late-onset rhabdoid tumor of the kidney.  相似文献   
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