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101.
Sox 基因家族在胚胎发育过程和性别分化中起重要作用, 为研究池蝶蚌中Sox 基因的功能, 以人SRY基因HMG-box 保守区的序列设计简并引物, 以雌、雄池蝶蚌基因组DNA 和精巢cDNA 为模板进行扩增, 获得了2 个不完全相同的序列, 分别为DNA-HMG1、DNA-HMG2 和cDNA-HMG, 长度均为220 bp, 编码73个氨基酸。与人等物种Sox1、Sox2、Sox3 及Sox14 有很高的同源性, 雌雄个体之间没有序列差异性。采用RACE-PCR 扩增获得了池蝶蚌性腺Sox2 部分cDNA 片段, 长度为1774 bp, 该序列核苷酸与欧洲帽贝的SoxB和人类的Sox2 的同源性最高; 在部分开放阅读框249 个氨基酸残基中, 具有Sox 家族典型的HMG-box 结构域, 与人类、小鼠、原鸡和斑马鱼等Sox2 的HMG-box 同源性为98%。为了解该基因在各组织中的表达情况,采用实时荧光定量PCR 方法分析了外套膜、闭壳肌、鳃、肠、肝、肾、精巢和卵巢在内的8 种组织hs-Sox2的表达情况, 结果显示, hs-Sox2 基因在8 种组织中均有表达, 其中在肾脏中的表达量最高, 其次是肠与闭壳肌, 在雄性性腺中的表达量明显高于雌性性腺, 在肝脏中的表达量最低; 为了解hs-Sox2 在不同性腺发育时期的表达情况, 采用实时荧光定量PCR 方法分析了5 个不同月龄的精巢组织中hs-Sox2 的表达情况, 结果显示在39 月龄性腺的表达量最高, 其次是16 月龄性腺, 63 月龄蚌中的表达量最少。以上结果表明, hs-Sox2 基因可能参与了池蝶蚌精巢的发育及功能的维持。    相似文献   
102.
Pancreatic adenosquamous carcinoma (PASC) — a rare pathological pancreatic cancer (PC) type — has a poor prognosis due to high malignancy. To examine the heterogeneity of PASC, we performed single-cell RNA sequencing (scRNA-seq) profiling with sample tissues from a healthy donor pancreas, an intraductal papillary mucinous neoplasm, and a patient with PASC. Of 9,887 individual cells, ten cell subpopulations were identified, including myeloid, immune, ductal, fibroblast, acinar, stellate, endothelial, and cancer cells. Cancer cells were divided into five clusters. Notably, cluster 1 exhibited stem-like phenotypes expressing UBE2C, ASPM, and TOP2A. We found that S100A2 is a potential biomarker for cancer cells. LGALS1, NPM1, RACK1, and PERP were upregulated from ductal to cancer cells. Furthermore, the copy number variations in ductal and cancer cells were greater than in the reference cells. The expression of EREG, FCGR2A, CCL4L2, and CTSC increased in myeloid cells from the normal pancreas to PASC. The gene sets expressed by cancer-associated fibroblasts were enriched in the immunosuppressive pathways. We demonstrate that EGFR-associated ligand-receptor pairs are activated in ductal-stromal cell communications. Hence, this study revealed the heterogeneous variations of ductal and stromal cells, defined cancer-associated signaling pathways, and deciphered intercellular interactions following PASC progression.  相似文献   
103.
Reactive oxygen species (ROS) are an important factor in the development of skin lesions in diabetes. A new antioxidant, hydrogen, can selectively neutralize hydroxyl radicals (OH) and peroxynitrite (ONOO) in cell-free systems, whereas it seldom reacts with other ROS. Fibroblasts are a key component of skin. In the present study, we investigated the protective effects of hydrogen-rich medium on human skin fibroblasts (HSFs) under oxidative stress. Confocal microscopy was used to assay both the intracellular superoxide anion () concentration and the mitochondrial membrane potential (ΔΨ). Cell viability was determined using the Cell Counting Kit-8 (CCK-8). The concentrations of cellular malonaldehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 3-nitrotyrosine (3-NT) were also measured. The results revealed that both mannitol and high glucose could cause oxidative stress in HSFs. Interestingly, the use of a hydrogen-rich medium significantly reduced the level of intracellular , stabilized the ΔΨ and attenuated production of MDA, 8-OHdG and 3-NT which efficiently enhanced the antioxidative defense system and protected the HSFs from subsequent oxidative stress damage. In other words, hydrogen decreased the excessive generation of intracellular and elevated the cellular antioxidative defense. Based on our results, hydrogen may have applications in the treatment of skin diseases caused by diabetes.  相似文献   
104.
Objective: To investigate the expression status of human carcinoma antigen (HCA) in human cholangiocellular carcinomas, and to determine the relationship between HCA and clinical features. Methods: Tissues from 60 intrahepatic cholangiocellular carcinoma (ICC) patients, and normal liver tissues from 20 hepatic hemangioma patients selected randomly were assayed for the expression of HCA by immunohistochemistry, and Western blots. Areas of poorly differentiated (n = 20), moderately-well differentiated (n = 30), highly differentiated tumors (n = 10) from different cases were evaluated. Results were recorded as positive (?5% of cells staining and staining intensity 2+ or 3+) or negative (<5% of cells staining and staining intensity <2+) and analyzed using the χ2 test. Results: BCE075 and BDD048 antibodies showed similar staining patterns. The positive immunostaining of BCE075 was mainly localized in the cytoplasm and cell secretions. The staining was positive in 15% of poorly differentiated ICC, 72% of moderately-well differentiated, 100% of highly differentiated tumors. But, staining was not detected in adjacent normal tissue. The differences in HCA expression among these tissues were statistically significant. Also, we found expression of HCA to be closely associated with the degree of differentiation of ICC and tumor cell morphology. There was a correlation between expression of HCA and serum CA19-9. Conclusion: The data suggest that HCA is a potential marker for the diagnosis of cholangiocellular carcinoma.  相似文献   
105.
The purpose of this study was to compare the fatigue and tensile strengths of radicular dentin. Forty bovine lower central incisors were used, twenty teeth for the fatigue test and twenty teeth for the tensile test. Bovine teeth were each sectioned into coronal and radicular portions. Dentin slabs of 1mm thickness were prepared along the radicular tooth using a low-speed cutting machine and trimmed into dumbbell-shaped specimens. A dentin slab was harvested from each tooth. Subsequently, fatigue and tensile tests were performed in Hank's balanced saline solution at 37 °C. The staircase method was employed to determine fatigue strength and its standard deviation. Fracture surfaces were observed by scanning electron microscopy. Mean fatigue strength and tensile strength were 44.3±5.0 and 84.4±8.3 MPa, respectively. The fatigue strength of radicular dentin was significantly lower than the tensile strength. The fatigue strength of radicular dentin was only approximately one half of the tensile strength.  相似文献   
106.
107.
This phase I study evaluated the feasibility of expanding HER-2/neu (HER2) vaccine-primed peripheral blood T-cells ex vivo and assessed the safety of T-cell infusions. Eight patients with HER2+ treatment refractory metastatic cancers were enrolled. T-cells could be expanded to predefined parameters in seven patients (88 %). Ninety-two percent of adverse events were grade 1 or 2. Three of seven patients developed infusion-related inflammatory reactions at their disease sites. HER2-specific T-cells significantly increased in vivo compared to pre-infusion levels (p = 0.010) and persisted in 4/6 patients (66 %) over 70 days after the first infusion. Partial clinical responses were observed in 43 % of patients. Levels of T-regulatory cells in peripheral blood prior to infusion (p < 0.001), the level of HER2-specific T-cells in vivo (p = 0.030), and development of diverse clonal T-cell populations (p < 0.001) were associated with response. The generation of HER2 vaccine-primed autologous T-cells for therapeutic infusion is feasible and well tolerated. This approach provides a foundation for the application of T-cell therapy to additional solid tumor types.  相似文献   
108.

Background

Electrical stimulation (ES) has been proven to be an effective means of enhancing the speed and accuracy of nerve regeneration. However, these results were recorded when the procedure was performed almost immediately after nerve injury. In clinical settings, most patients cannot be treated immediately. Some patients with serious trauma or contaminated wounds need to wait for nerve repair surgery. Delays in nerve repair have been shown to be associated with poorer results than immediate surgery. It is not clear whether electrical stimulation still has any effect on nerve regeneration after enough time has elapsed.

Methods

A delayed nerve repair model in which the rats received delayed nerve repair after 1 day, 1 week, 1 month, and 2 months was designed. At each point in time, the nerve stumps of half the rats were bridged with an absorbable conduit and the rats were given 1 h of weak electrical stimulation. The other half was not treated. In order to analyze the morphological and molecular differences among these groups, 6 ES rats and 6 sham ES rats per point in time were killed 5 days after surgery. The other rats in each group were allowed to recover for 6 weeks before the final functional test and tissue observation.

Results

The amounts of myelinated fibers in the distal nerve stumps decreased as the delay in repair increased for both ES rats and sham ES rats. In the 1-day-delay and 1-week-delay groups, there were more fibers in ES rats than in sham ES rats. And the compound muscle action potential (CMAP) and motor nerve conduction velocity (MNCV) results were better for ES rats in these two groups. In order to analyze the mechanisms underlying these differences, Masson staining was performed on the distal nerves and quantitative PCR on the spinal cords. Results showed that, after delays in repair of 1 month and 2 months, there was more collagen tissue hyperplasia in the distal nerve in all rats. The brain-derived neurotrophic factor (BDNF) and trkB expression levels in the spinal cords of ES rats were higher than in sham ES rats. However, these differences decreased as the delay in repair increased.

Conclusions

Electrical stimulation does not continue to promote nerve regeneration after long delays in nerve repair. The effective interval for nerve regeneration after delayed repair was found to be less than 1 month. The mechanism seemed to be related to the expression of nerve growth factors and regeneration environment in the distal nerves.  相似文献   
109.

Background

The awareness, treatment and control of diabetes mellitus (DM) can effectively reflect on the social status of diabetes conditions. Although several researchers have investigated the awareness, treatment and control rates of diabetes mellitus in China, little is known about their association with risk factors. This study aims to examine the relationship between risk factors and awareness, treatment and control of diabetes mellitus in northeast China.

Methods

A cross-sectional survey was conducted in 2012. Multistage stratified random cluster sampling design was used to select participants aged 18 to 79 years old. The analysis was based on a representative sample of 1,854 adult subjects. Multivariable logistic regression analysis was used to examine socio-demographic factors associated with the levels of awareness, treatment and control of diabetes mellitus.

Results

The awareness, treatment, and control rates of diabetes mellitus were 64.1%, 52.9% and 44.2%, respectively. In the multivariable logistic regression analysis, family history of diabetes was significantly positively associated with awareness (OR, 2.145; 95% CI, 1.600–2.875) and treatment (OR, 2.021; 95% CI, 1.559–2.619) of diabetes mellitus, while negatively associated with control (OR, 0.671; 95% CI, 0.529–0.951). Cigarette smokers and alcohol drinkers were less likely than non-smokers and non-drinkers to be aware of their blood glucose levels (OR, 0.895, 0.614; 95% CI, 0.659–1.216, 0.446–0.844, respectively). Participants who frequently exercise were more likely to be aware of their diabetic conditions than people who never or rarely exercise (OR, 2.003; 95% CI, 1.513–2.651).

Conclusions

We found that the awareness and treatment of diabetes mellitus were positively associated with age and were high in participants with a family history of diabetes and those who exercise frequently, but low for cigarette smokers and alcohol drinkers. Participants with a family history of diabetes had their diabetic condition poorly controlled.  相似文献   
110.
Crimean-Congo hemorrhagic fever (CCHF), a severe viral disease known to have occurred in over 30 countries and distinct regions, is caused by the tick-borne CCHF virus (CCHFV). Nucleocapsid protein (NP), which is encoded by the S gene, is the primary antigen detectable in infected cells. The goal of the present study was to map the minimal motifs of B-cell epitopes (BCEs) on NP. Five precise BCEs (E1, 247FDEAKK252; E2a, 254VEAL257; E2b, 258NGYLNKH264; E3, 267EVDKA271; and E4, 274DSMITN279) identified through the use of rabbit antiserum, and one BCE (E5, 258NGYL261) recognized using a mouse monoclonal antibody, were confirmed to be within the central region of NP and were partially represented among the predicted epitopes. Notably, the five BCEs identified using the rabbit sera were able to react with positive serum mixtures from five sheep which had been infected naturally with CCHFV. The multiple sequence alignment (MSA) revealed high conservation of the identified BCEs among ten CCHFV strains from different areas. Interestingly, the identified BCEs with only one residue variation can apparently be recognized by the positive sera of sheep naturally infected with CCHFV. Computer-generated three-dimensional structural models indicated that all the antigenic motifs are located on the surface of the NP stalk domain. This report represents the first identification and mapping of the minimal BCEs of CCHFV-NP along with an analysis of their primary and structural properties. Our identification of the minimal linear BCEs of CCHFV-NP may provide fundamental data for developing rapid diagnostic reagents and illuminating the pathogenic mechanism of CCHFV.  相似文献   
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