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Introduction
Epidemiological studies have evaluated the association between factor XIII-A (FXIII-A) Val34Leu polymorphism and risk of ischemic stroke, but the results remain inconclusive. This meta-analysis was therefore designed to clarify these controversies.Methods
Systematic searches of electronic databases Embase, PubMed and Web of Science, as well as hand searching of the references of identified articles and the meeting abstracts were performed. Study selection, data abstraction and study quality evaluation (using the Newcastle-Ottawa Scale, NOS) were independently conducted in duplicate. Statistical analyses were performed using software Review Manager (Version 5.1.2) and Stata (Version 11.0). The pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were performed. Fixed or random effects model was separately used depending on the heterogeneity between studies. Publication bias was tested by funnel plot, Egger's regression test and Begg's test. Sensitivity analysis was conducted by limiting the meta-analysis to the high quality studies (NOS score≥8).Results
A total of 16 studies including 3,807 cases and 4,993 controls were combined showing no evidence of association between FXIII-A Val34Leu polymorphism and ischemic stroke (for Val/Leu vs. Val/Val : OR = 0.95, 95%CI = 0.77-1.16; for Leu/Leu vs. Val/Val: OR = 0.90, 95%CI = 0.73-1.11; for dominant model: OR = 0.97, 95%CI = 0.81-1.17; for recessive model: OR = 0.95, 95%CI = 0.77-1.17). In the subgroup analyses by study design, ethnicity and specific subtypes (small-vessel occlusive ischemic stroke and large-artery atherosclerotic ischemic stroke ), there was lack of evidence for the association.Conclusions
This meta-analysis indicates that there is no evidence for association between factor XIII-A Val34Leu polymorphism and ischemic stroke. 相似文献63.
Background: Combination treatment (chemoradiotherapy) is the standard treatment for locally advanced head and neck squamous cell carcinoma (HNSCC); however, treatment resistance and local recurrence are significant problems. A high level of epidermal growth factor receptor (EGFR) has been associated with a more aggressive phenotype as well as decreased responsiveness to radio‐ or chemotherapy. We examined the role of EGFR status and EGFR ligand expression for the treatment response. Methods: Intrinsic sensitivity to radiotherapy, cisplatin, and cetuximab treatments was investigated in 25 HNSCC cell lines. EGFR gene copy number, mRNA and protein expression, EGFR and Akt phosphorylation status, and mRNA expression of the EGFR ligands were analyzed using quantitative PCR and ELISA and assessed for their impact on treatment sensitivity. Results: Different treatment modalities yielded great diversity in outcome; of note, cetuximab treatment stimulated growth in one cell line. When treatments were combined primarily additive effects were observed. While radioresistance tended to be associated with a high level of phosphorylated EGFR (pEGFR; P = 0.09), cetuximab‐resistant cells had low levels of pEGFR (P = 0.13). The three most cetuximab‐sensitive cell lines had high EGFR gene copy numbers. Furthermore, cetuximab treatment response was significantly correlated with epiregulin mRNA expression (r = ?0.408, P = 0.043). Cisplatin‐resistant tumor cells expressed significantly lower levels of EGFR protein (P = 0.04) compared to cisplatin‐sensitive cells and tended to have lower levels of phosphorylated Akt (pAkt; P = 0.13) and lower expression levels of amphiregulin (P = 0.18). Conclusions: Epidermal growth factor receptor status and ligand expression influence the treatment sensitivity of HNSCC cells and may be useful as predictive markers. 相似文献
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面神经功能3种评价方法的相关性研究 总被引:1,自引:0,他引:1
目的:通过比较House-Brackmann评价(HB评价)、临床量化面神经功能评价系统(QFES)和面神经神经电图检查(ENoG)3种不同方法之间的相关性,探讨这些方法在面神经损伤后不同时期的应用价值。方法:选取1999-2007年因各种原因引起面神经损伤的患者共81例(男52例,女29例)。根据患者病历资料,获得同一时间点的HB评价结果、QFES评价结果和ENoG结果。采用SPSS13.0软件包行不同方法之间的相关分析。结果:HB评价和QFES评价之间具有较好的相关性;QFES评价和ENoG之间存在弱相关;面神经解剖性损伤后1个月内,ENoG和QFES评价之间有较强的相关性(r=0.523,P〈0.001),1个月之后,两者之间无明显相关(r〈0.4,P〉0.05)。结论:QFES系统测量结果和HB评价结果之间存在一致性;ENoG检查结果和QFES评价所代表的面部运动功能恢复情况之间不一致;创伤性面瘫发生后1个月内,ENoG结果和面部运动功能改变之间有一定相关。 相似文献
67.
Chi-Yung Shang Susan Shur-Fen Gau Chih-Min Liu Hai-Gwo Hwu 《Progress in neuro-psychopharmacology & biological psychiatry》2011,35(2):421-428
Attention deficit hyperactivity disorder (ADHD) is a common heritable childhood psychiatric disorder. Since methylphenidate, one of the main drugs used to treat ADHD, targets the dopamine transporter, this study examined the linkage disequilibrium (LD) structure of the dopamine transporter gene (DAT1) and investigated whether the DAT1 gene was associated with ADHD. This Chinese family-based association sample consisted of 273 DSM-IV diagnosed ADHD probands and their family members (n = 906). We screened 15 polymorphisms across the DAT1 gene, including 14 single nucleotide polymorphism (SNP) markers and the variable number of tandem repeat (VNTR) polymorphism in 3′-untranslated region (3′UTR). Calculations of pairwise LD revealed three main haplotype blocks (HBs): HB1 (intron 2 through intron 6), HB2 (intron 8 through intron 11), and HB3 (3′UTR). Family-Based Association Tests showed that no allele was significantly more transmitted than expected to the ADHD children for these 15 markers. Haplotype-Based Association Tests showed that a haplotype rs27048 (C)/rs429699 (T) was significantly associated with the inattentive subtype (P = 0.008). In quantitative analyses, this haplotype also demonstrated significant association with the inattention severity (P = 0.012). Our finding of the haplotype rs27048 (C)/rs429699 (T) as a novel genetic marker in the inattentive ADHD subtype suggests that variation in the DAT1 gene may primarily affect the inattentive subtype of ADHD. 相似文献
68.
A third case of corpus callosum hemangioblastoma (HB) is presented. With no preoperative embolization, surgery was uneventful and the postoperative course was excellent. Based on the literature, we attempted to clarify the histogenesis of HB and to explain why they are exceptional in the supratentorial region in contrast to the posterior cranial fossa. The VHL gene is expressed particularly in Purkinje cells of the cerebellum, but this expression is also possible in supratentorial structures. Its mutation leads to developmental arrest of angioblasts that become potentially neoplastic cells. These CD133-positive pluripotent neoplastic angioblasts, similar to stem cells, may be immature HB in the brain. They also express VEGF, coexpress Epo/EpoR, and are capable of differentiation into primitive vascular structures. This coexpression may not only mediate developmental stagnation, but may also induce HB proliferation. Therefore, HB tumorigenesis may be initiated during embryogenesis and may originate from angiomesenchyma because of the expression of three cell types (stromal cells, pericytes, and endothelial cells) in vimentin. Their capacity for proliferation and differentiation in HB depends on the microenvironment. 相似文献
69.
Immunohistochemical staining of cancer stem cell markers in hepatocellular carcinoma 总被引:1,自引:0,他引:1
Shilpa Lingala Yi-Yao Cui Xiaoli Chen Xiao-Feng Qian Jian Wu 《Experimental and molecular pathology》2010,89(1):27-2030
Background
Cancer stem cells (CSCs) are thought to be a critical subpopulation in tumor development, progression, metastasis and recurrence, and the identification of these cells is an initial step in understanding their role in oncogenesis and in seeking valuable markers for diagnosis or development of targeting therapeutics.Aims
To identify CSCs in hepatocellular carcinoma (HCC) specimens and define their tissue specificity.Methods
Immunohistochemical staining of CSC markers: CD44, CD90, CD133 and aldehyde dehydrogenase (ALDH) was performed in 25 HCC specimens, 4 hepatoblastomas, 8 peri-malignant tissues, and 19 cases of viral hepatitis.Results
The positivity of CD44 staining in HCC specimens was significantly lower than in viral hepatitis specimens. The positive rate of CD133 in HCC was similar to viral hepatitis specimens. CD133+ cells were largely localized to ALDH-positive cells in HCC as revealed by confocal microscopy. In contrast, the co-expression of both markers was visualized within vessels or in the portal areas in viral hepatitis. Moreover, among 7 liver specimens adjacent to HCC tissue, 3-6 samples were positive for CD44, CD90, CD133 and ALDH, especially in dysplastic cells. One of 4 hepatoblastoma cases was positive for all these markers; whereas, the other three specimens were negative for all these CSC markers.Conclusions
In HCC and dysplastic tissues, clusters of CD133+/ALDHhigh cells were identified. The use of cancer stem cell markers to screen tissues with chronic liver diseases provides limited guidance in the identification of malignant cells. 相似文献70.
Characteristics of a cancerous cell line, HIOEC-B(a)P-96, induced by benzo(a)pyrene from human immortalized oral epithelial cell line 总被引:1,自引:0,他引:1
Zhong LP Pan HY Zhou XJ Ye DX Zhang L Yang X Chen WT Zhang ZY 《Archives of oral biology》2008,53(5):443-452
Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the oral and maxillofacial region. The mechanism of carcinogenesis of OSCC is still unclear. In vitro study on OSCC cell lines, especially derived from immortalized oral epithelial cells, is a very useful strategy to understand the mechanism of carcinogenesis. Based on our previous human immortalized oral epithelial cell (HIOEC) line, obtained from normal oral epithelial cells by transfection of HPV16 E6/E7 gene, a new cancerous cell line, HIOEC-B(a)P-96 (HB96), was established from the HIOEC by induction with benzo(a)pyrene. The characteristics of the HB96 cells such as cell morphology, ultrastructure, proliferation ability, invasion ability, and tumorigenesis were studied. The HB96 cells lost contact inhibition with uncontrolled cell division and obvious cell overlap, they were polygonal in shape and ununiform in size with increased ratio between nucleus and plasma. Increased proliferative ability and invasion ability were confirmed by the cell proliferation analysis and cell invasion assay, respectively. The tumorigenicity of well to moderately differentiated squamous cell carcinoma was confirmed in the nude mice experiments pathologically. Increased expression of HPV16 E6/E7 proteins and obvious correlation with decreased expression of p53 and Rb proteins was also confirmed by Western blotting. Thus, this HB96 cell line induced by benzo(a)pyrene from the HIOEC line is a useful tool to study the mechanism of carcinogenesis of OSCC in vitro for future genomic and proteomic analyses. It is also the first in vitro cancerous cell line of OSCC in China derived from immortalized oral epithelial cells. 相似文献