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31.
Neurosurgical Review - Cauda equina paragangliomas are rare benign extra-adrenal neuroendocrine tumours arising from the neural crest cells associated with autonomic ganglia. These tumours are...  相似文献   
32.
Modulation of fibrogenesis, epithelial, and mesenchymal cell fates are prominent effects of transforming growth factor-beta (TGF-beta) signaling by Smad proteins. We have previously shown that Smad2 and Smad3 insufficiency leads to a loss of bile ducts. In addition, Smad3/4 activity is mediated by embryonic liver fodrin (ELF), a beta-Spectrin. In mouse elf(-/-) mutants and in liver explant cultures, loss of ELF function results in T lymphocytic proliferation and absent intrahepatic bile ducts. A similar phenotype is seen in a number of cholestatic diseases with progressive loss of intrahepatic bile ducts and fibrosis. However, the expression patterns of Smads or role of ELF in cholestatic and fibrotic liver diseases are not yet known. METHODS/RESULTS: We investigated the role of ELF in primary biliary cirrhosis (PBC), autoimmune hepatitis C, chronic viral hepatitis and in livers from mice deficient in Smad2/Smad3. We generated elf(+/-) mutant mice and analyzed for chronic liver disease and hepatocellular cancer (HCC) from 6 to 12 months. Perturbations in ELF expression were consistently seen only in PBC tissues. ELF expression was similarly aberrant in tissues from Smad2(+/-)/Smad3(+/-) mutant mice. Further studies indicated that ELF mislocalization is correlated with aberrant localization of Smad3 in some PBC tissues. Thirteen of 17 elf(+/-) mutant mice developed steatosis, fibrosis, hepatic dysplasia, with HCC in two mice. CONCLUSIONS: These results suggest that a compromised cytoarchitecture and polarized trafficking of TGF-beta signaling molecules, ELF and Smad3 are involved in the pathogenesis of PBC as well as HCC.  相似文献   
33.
34.

Objective

Heat shock during restorative procedures can trigger damage to the pulpodentin complex. While severe heat shock has toxic effects, fever-range heat stress exerts beneficial effects on several cells and tissues. In this study, we examined whether continuous fever-range heat stress (CFHS) has beneficial effects on thermotolerance in the rat clonal dental pulp cell line with odontoblastic properties, KN-3.

Methods

KN-3 cells were cultured at 41 °C for various periods, and the expression level of several proteins was assessed by Western blot analysis. After pre-heat-treatment at 41 °C for various periods, KN-3 cells were exposed to lethal severe heat shock (LSHS) at 49 °C for 10 min, and cell viability was examined using the MTS assay. Additionally, the expression level of odontoblast differentiation makers in surviving cells was examined by Western blot analysis.

Results

CFHS increased the expression levels of several heat shock proteins (HSPs) in KN-3 cells, and induced transient cell cycle arrest. KN-3 cells, not pre-heated or exposed to CFHS for 1 or 3 h, died after exposure to LSHS. In contrast, KN-3 cells exposed to CFHS for 12 h were transiently lower on day 1, but increased on day 3 after LSHS. The surviving cells expressed odontoblast differentiation markers, dentine sialoprotein and dentine matrix protein-1. These results suggest that CFHS for 12 h improves tolerance to LSHS by inducing HSPs expression and cell cycle arrest in KN-3 cells.

Conclusions

The appropriate pretreatment with continuous fever-range heat stress can provide protection against lethal heat shock in KN-3 cells.  相似文献   
35.
36.
Optical clearing methods are widely used for three-dimensional biological information acquisition in the whole organ. However, the imaging quality of cleared tissues is often limited by ununiformed tissue clearing. By combining tissue clearing with mechanical sectioning based whole organ imaging system, we can reduce the influence of light scattering and absorption on the tissue to get isotropic and high resolution in both superficial and deep layers. However, it remains challenging for optical cleared biological tissue to maintain good sectioning property. Here, we developed a clearing method named M-CUBIC (machinable CUBIC), which combined a modified CUBIC method with PNAGA (poly-N-acryloyl glycinamide) hydrogel embedding to transparentize tissue while improving its sectioning property. With high-throughput light-sheet tomography platform (HLTP) and fluorescent micro-optical sectioning tomography (fMOST), we acquired continuous datasets with subcellular resolution from intact mouse brains for single neuron tracing, as well as the fine vascular structure of kidneys. This method can be used to acquire microstructures of multiple types of biological organs with subcellular resolutions, which can facilitate biological research.  相似文献   
37.
急性心肌梗塞Q-Td与预后关系的探讨   总被引:1,自引:5,他引:1  
目的 :探讨急性心肌梗塞 Q- Td与其预后的关系。方法 :分析 52例急性心肌梗塞患者的 Q- Td与有、无心源性休克、急性左心衰竭、室性心律失常和心源性死亡的关系。结果 :急性心肌梗塞伴有室性心律失常组的 Q- Td明显长于无室性心律失常组 (P<0 .0 0 1) ,心源性死亡组 Q- Td明显长于存活组(P<0 .0 1)。结论 :急性心肌梗塞 Q- Td对于预测其预后有一定价值。  相似文献   
38.
Prognostic factors for chronic active Epstein-Barr virus infection   总被引:11,自引:0,他引:11  
Chronic active Epstein-Barr virus infection (CAEBV) is a high-mortality and high-morbidity disease. To clarify the prognostic factors, a national survey was performed in Japan, and data for 82 patients who met the criteria for CAEBV were analyzed. Of these 82 patients, 47 were alive and 35 had already died. Multivariate analysis revealed that thromobocytopenia and age at disease onset were correlated with mortality. The probability of 5-year survival was 0.45 for older patients (onset age, > or = 8 years), 0.94 for younger patients (P<.001), 0.38 for patients with thrombocytopenia (platelet count < 12 x 10(4) platelets/microL at diagnosis), and 0.76 for patients without thrombocytopenia (P=.01). Furthermore, patients with T cell infection by EBV had shorter survival times than patients with natural killer cell infection (probability of 5-year survival, 0.59 vs. 0.87; P<.009). Patients with CAEBV with late onset of disease, thrombocytopenia, and T cell infection had significantly poorer outcomes.  相似文献   
39.
Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in skeletal mass in patients who are infected with hepatitis C virus (HCV). The clinical presentation is an acquired deep bone pain with increased serum alkaline phosphatase (ALP) activity. We present a case of a patient with HCAO who was treated with antiviral therapy. A 42-year-old Japanese man presented with severe, stabbing pain in his lower limbs. He was diagnosed with hepatitis C secondary to intravenous drug use 20 years earlier. Serum biochemical studies revealed markedly elevated ALP activity and osteocalcin levels. Skeletal radiographs showed diffuse bony sclerosis with marked cortical thickening in the long bones. The bony findings and clinical symptoms were attributed to HCAO. The HCV RNA viral load was high and the genotype was 2a. The patient was treated with peginterferon alfa-2b and ribavirin for 24 weeks. After 24 weeks of the combination therapy, the patient had a sustained virological response and clinical remission of bone pain and a decrease in the level of serum ALP. In conclusion, HCAO was improved by the combination therapy of peginterferon alfa-2b and ribavirin when the patient achieved sustained virological response. It was confirmed that HCAO was one of the extrahepatic manifestations of HCV.  相似文献   
40.

Background

Sleeve gastrectomy plus side-to-side jejunoileal anastomosis (JI-SG), a relatively new approach to bariatric surgeries, has shown promising results for treating obesity and metabolic comorbidities. This study investigated the feasibility and safety of JI-SG in weight loss and diabetes remission compared with sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB).

Methods

Forty 10-week-old male Zucker diabetic fatty rats were randomly assigned to four groups: control, SG, JI-SG, and RYGB. Their body weights, food intake, and levels of gut hormones (ghrelin, insulin, and glucagon-like peptide-1 (GLP-1)) and lipids were measured.

Results

Rats in the SG, JI-SG, and RYGB groups demonstrated lower food intake and more weight loss 2 weeks postoperatively compared with control rats. Furthermore, rats in the JI-SG group achieved more weight loss (mean 242.7?±?11.2 g) compared with those in the SG and RYGB groups (SG, 401.4?±?15.1 g and RYGB, 298?±?12 g, both P?<?0.01). All surgery groups demonstrated a decreased fasting insulin, serum glucose, lipid levels, and increased GLP-1 postoperatively. The JI-SG group had lower fasting ghrelin levels than the RYGB group (168?±?19.8 ng/L vs. 182?±?16.7 ng/L, P?<?0.01) and higher fasting GLP-1 levels than the SG group (1.99?±?0.11 pmol/L vs. 1.71?±?0.12 pmol/L, P?<?0.01) at 12 weeks postoperatively. Over the experimental period, the ghrelin levels slowly increased in all surgical groups but remained lower than the preoperative and control levels.

Conclusions

JI-SG induced higher ghrelin and GLP-1 levels and improved glycemic control in Zucker diabetic fatty rats. Compared with SG and RYGB, JI-SG appeared to be a simple, relatively safe, and more effective procedure for treating type 2 diabetes and obesity in this animal model.
  相似文献   
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