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991.
Background: The failure of intestinal mucosal barrier may induce multiple organ dysfunction and systemic inflammatory response syndrome, but little work has been done on whether hypobaric hypoxia related to the failure of intestinal mucosal barrier. Aims: To study the expression of hypoxia-inducible factor 1α (HIF-1α), inducible nitric oxide synthase (iNOS) and morphological changes of intestinal mucosa in albino rats at different altitude. Methods: 30 male Wistar rats raised in plain for one month were randomly divided into 3 groups: Plain 500 m group (n=10), High-altitude (HA) 3842 m group (n=10) and HA4767 m group (n=10). Each group was delivered to different altitude area at the same shipping time and executed after 3 days’ exposure to different altitude. Intestinal segments with the same location of all rats were removed for morphological analyses. Morphologic parameters (villous height, crypt depth, mucosal wall thickness and villous surface area) were measured by optical and scanning electron microscope. The expression of iNOS and HIF-1α were detected by immunohistochemistry. Results: Morphological indexes in higher altitude groups were exacerbated obviously compared with those of lower altitude groups. While the expression of iNOS and HIF-1α in higher altitude groups were significantly increased than those of lower altitude groups. Linear correlation analysis showed that the expression of iNOS was positively correlated with that of HIF-1α. Conclusions: Hypobaric hypoxia increases the expression of HIF-1α and iNOS in intestinal mucosa, however exacerbates the mucous morphologic parameters with altitude increasing. HIF-1α may regulate the expression of iNOS and be involved in the damage of intestinal mucosa.  相似文献   
992.
Background: Microalbuminuria is the earliest clinical sign of diabetic nephropathy (DN). However, earlier markers as a diagnostic tool for DN was required for the invalid of microalbuminuria in some cases. Osteoinductive factor (OIF) was known to be an essential component of the normal vascular matrix. We aimed to research the relationship between DN and OIF, and discussed the availability of the serological markers for earlier stage of DN. Method: One hundred twenty Chinese subjects, who included patients with type 2 diabetes mellitus (T2DM), DN with microalbuminuria, and DN with macroalbuminuria, as well as healthy controls, were enrolled in this study. Serum OIF levels were examined by ELISA and other clinical biochemical parameters were tested based on standard methods. Results: Our results indicated that, serum OIF levels were significantly increased in DN subjects compared with healthy and T2DM subjects (P < 0.05 respectively). However, no significant changes in serum OIF levels were found between T2DM and healthy subjects. Furthermore, serum OIF had negative correlation with estimated glomerular filtration rate (eGFR) and positive correlation with blood urea nitrogen(BUN) and creatinine. ROC curve analysis showed that serum OIF level was a good sensitive and specificity marker for microalbuminuria and early renal damage with sensitivity of 86.7% and specificity of 95%, as well as for macroalbuminuria and damage progress with sensitivity of 90% and specificity of 95%. Conclusion: OIF may be an indicator of the earlier-stage DN in subjects with T2DM. Understanding the exact mechanism of up-regulated OIF in subjects with DN requires further study.  相似文献   
993.
We conducted a case-control study to investigate the role of ABCB1 C3435T and G2677T/A in the susceptibility and prognosis of colorectal cancer patients. A total of 316 patients with colorectal cancer and 316 controls were collected between January 2009 and January 2011. Genotyping of ABCB1 C3435T and G2677T/A was conducted by the methods of Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Conditional logistic regression analysis showed that subjects carrying CT and CC genotypes of ABCB1 C3435T were more frequently observed in colorectal cancer patients when compared with controls, and the adjusted ORs were 1.62 (1.05-2.52) and 2.05 (1.25-3.36), respectively. By Cox regression analysis, we found that the TT genotype of ABCB1 C3435T was significantly associated with shorter PFS and OS in patients with colorectal cancer when compared with CC genotype, with adjusted HR (95% CI) of 2.57 (1.14-6.04) and 2.54 (1.05-6.61), respectively. We found that the ABCB1 C3435T polymorphism could affect the susceptibility and clinical outcome of colorectal cancer patients.  相似文献   
994.
Severe aplastic anemia (SAA) is a bone marrow failure disease induced by hyperfunctional autoimmunic Th1 lymphocytes. Memory T cells (TM) are a component of the adaptive immune system. They ensure the host of more aggressive and faster immune response to efficiently eliminate the specific antigens after re-exposure and thus play a key role in T-cell functions. In this study we investigate the quantities and functions of memory T cells in SAA patients before and after immunosuppressive therapy (IST) to further clarify the mechanism of SAA apoptosis of bone marrow hematopoietic cells. Results showed that the percentage of CD4+ effector T cells in peripheral blood and bone marrow lymphocytes was decreased in SAA patients. The ratio of CD4+ memory T lymphocytes to CD8+ memory T subsets (CD4+/CD8+TM) in SAA patients was also lower. The percentage of CD8+ effector T cells in peripheral blood and CD8+ central memory T cells in the bone marrow lymphocytes was significantly higher in newly diagnosed patients. Furthermore, the median expressions of perforin and granzyme B on memory T cells were higher in SAA patients compared to those in normal controls. After IST, the quantities and functions of memory T cells return to normal level. Therefore, we concluded that the abnormal immunomodulatory ability on memory T cells may contribute to the imbalance of Th1/Th2 subsets and thus lead to over-function of T lymphocytes and hematopoiesis failure in SAA.  相似文献   
995.
996.
Backgound: Renal epithelioid angiomyolipoma (EAML) is a rare variant of AML (angiomyolipoma) and is often associated with aggressive behaviors. The pathogenesis of EAML has been poorly understood. We analyzed the expression of p53 and Ki-67 by immunohistochemistry (IHC) and investigated p53 mutation analysis in 11 cases of EAML in comparison to classical AML. Methods: P53 and Ki-67 expression status were determined by IHC staining. P53 mutation analysis was performed using bi-directional sequencing. Results: Renal EAML tumors were significantly associated with more severe to moderate nuclear atypia (100% vs. 36.4%, P = 0.004) and mitotic activity (90.9% vs. 27.3%, P = 0.008) compared with AML tumors. Out of 11 cases of EAML, 8 were positive for p53. There was only 1 case with positive p53 expression in AML cases and expression of p53 protein showed significant difference between EAML and AML tumors (72.7% vs. 9.1%, P = 0.008). In addition, there were 7 AML and 6 EAML cases harbored P72R mutation (SNP) in exon 4 of p53. Compared with AML cases, 2 out of 11 cases of EMAL showed more than 10% positivity for ki-67. The finding of stronger p53 expression in renal EAML might have contributed to their malignant behavior. However, the abnormal p53 expression cannot be entirely explained by p53 mutations in the exons examined. Conclusions: Thus, the combination of immunohistochemical assessment of tumor antigens might improve our ability to predict the malignant outcome in EAML.  相似文献   
997.
As a negative regulatory molecule, T-cell immunoglobulin–and mucin domain-3 (Tim-3) plays a crucial role in the tumor immunological tolerance. In the present study, we aimed to determine the Tim-3 expression in gastric cancer tissue and its relationship with clinicopathological parameters and prognosis. The Tim-3 expression was assessed in 52 gastric cancer specimens and 15 gastritis tissues by flow cytometry, and gastritis tissues served as the control. As a result, we found that the Tim-3 expressions on CD4+T cells and CD8+T cells in gastric cancer tissue was significantly higher than those in gastritis tissue (P=0.022, P=0.047, respectively). The median expression level of Tim-3 on CD4+T cells were significantly correlated with clinicopathological parameters, such as tumor size, lymph node metastasis, the depth of tumor invasion and TNM staging (P=0.042, P=0.026, P=0.001, P=0.003, respectively), while it was not correlated with sex, age and histological subtype (all P>0.05). In CD8+T cells, the Tim-3 expression was relevant to tumor invasion and TNM staging (P=0.035, P=0.017, respectively), while it was irrelevant to other clinicopathological parameters (all P>0.05). Additionally, Kaplan-Meier survival curves showed that the median overall survival time of patients with lower Tim-3 expression was greater than that of patients with higher Tim-3 expression in CD4+T cells and CD8+T cells (χ2=18.036, P<0.001 and χ2=18.036, P<0.001, respectively). Moreover, the multivariate analysis revealed that the Tim-3 expression and TNM stage were independent prognostic factors for gastric cancer patients (P=0.029, P=0.043 and P=0.003, respectively). These results suggest that Tim-3 played an important role in the development and progression of gastric cancer, and it could be used as an independent prognostic factor for gastric cancer patients.  相似文献   
998.
Objective: The aim of this study was to characterize the mesenchymal stromal cells (MSCs) and endothelial progenitor cells (EPCs) mobilization, and bone turnover in osteoporotic fracture healing in ovariectomized mice. Methods: In total, 112 female C57/BL mice were divided into two groups. The first group was sham-operated (SO), and the other group was ovariectomized (OVX). After three weeks, the right femora of the mice were fractured under anesthesia and internally fixed with steel pin. Peripheral blood and bone marrow were was collected for flow cytometry analysis, at 0 hours (h), 12 h, 24 h, 72 h and 168 h after fracture. MSCs and EPCs levels were assessed using cell surface antigens in different combinations (CD44+ CD34-CD45-, and CD34+ KDR+CD45-) by flow cytometry. At 0, 14, 28 and 42 days after fracture, sera were assayed for circulating levels of procollagen type I-N-terminal propeptide (P1NP) and C-terminal telopeptide of type I-collagen (CTX) by ELISA. Femurs were harvested at 2 weeks and 6 weeks after fracture for X-ray radiography, micro-computed tomography (micro-CT) and histology. Results: Our results showed that bone marrow and peripheral blood MSCs numbers of the OVX mice were significantly lower than the SO mice, at 12 h, 24 h and 72 h after fracture. In addition, circulating P1NP and CTX levels of the OVX mice were significantly higher than the SO mice, at 2 and 4 weeks. Conclusion: Results of the present study revealed disorders of bone marrow MSCs mobilization and bone turnover may partially account for the delay of osteoporotic fracture healing.  相似文献   
999.
Hydatid disease, which is also known as cystic echinococcosis, is a zoonotic infection caused by the cestode tapeworm Echinococcus granulosus and rarely by Echinococcus multilocularis. In this report we describe an unusual case of a 19-year-old woman who was admitted to our hospital for abdominal pain, nausea, and vomiting. Computed tomography revealed multi-organ abdominal echinococcosis. The patient recovered after undergoing surgery to excise the cyst. The diagnosis, clinical features, treatment, and prevention in this case of multi-organ abdominal echinococcosis are discussed, in light of the relevant literature.  相似文献   
1000.
Objective: To investigate the relation of Fas and Fas ligand (FasL) protein expression with carcinogenesis and metastasis of cardiac carcinoma. Methods: Immunohistochemistry was used to detect Fas and FasL protein expression in 64 cardiac carcinoma tissue samples and 20 normal gastric tissue samples. Relation between FasL and Fas expression, age and gender of gastric cancer patients, and pathological subtype and lymph node metastasis of gastric cancer was analyzed. Results: The Fas expression level was significantly higher in normal gastric tissue samples than in cardiac carcinoma tissue samples (85.0% vs. 25.0%, P<0.001), while the FasL expression level was significantly lower in normal gastric tissue samples than in cardiac carcinoma tissue samples (30.0% vs. 81.3%, P<0.001). The Fas expression level was significantly higher in invasive lymph nodes than in non-invasive lymph nodes (82.9% vs. 56.5%, P<0.003) and in well-differentiated gastric carcinoma tissue samples than in poorly-differentiated cardiac carcinoma tissue samples (50.0% vs. 18.0%, P=0.015). The FasL expression level was significantly lower in well-differentiated cardiac carcinoma tissue samples than in poorly- differentiated cardiac carcinoma tissue samples (42.9% vs. 84.0%, P=0.021). The Fas and FasL expression levels (25.0% and 81.3%) were significantly different in cardiac carcinoma tissue samples (P<0.001), but had a non-linear correlation (P=0.575). Conclusion: Abnormal Fas and FasL expressions in cardiac carcinoma and lymph node tissues are involved in carcinogenesis and metastasis of gastric cancer.  相似文献   
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