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991.
Mall AS Tyler MG Ho SB Krige JE Kahn D Spearman W Myer L Govender D 《Pathology, research and practice》2010,206(12):805-809
Cholangiocarcinoma (CC) is a highly malignant epithelial cancer of the biliary tract, the cellular and molecular pathogenesis of which remains unclear. Malignant transformation of glandular epithelial cells is associated with the altered expression of mucin. We investigated the type of mucins expressed in CC. Twenty-six patients with histologically confirmed CC were included in this study. The expression of mucin was studied by immunohistochemistry using antibodies to MUC1, MUC1 core, MUC2, MUC3, MUC4, MUC5AC, and MUC6. There was extensive (>50%) expression of mucin, mainly MUC1 in 11/25 and MUC5AC in 12/26 cases. In the case of MUC3, 6/26 cases expressed mucin extensively, whilst only 1/26 had MUC2, MUC4, and MUC6 expression. Well-differentiated tumors significantly expressed MUC3 extensively compared to poor or moderately differentiated tumors (p=0.003). Fifteen of 25 cases had metastatic disease. MUC1 was extensively expressed in 9/15 cases with metastatic disease. In contrast, MUC1 expression was present in 2/10 cases where metastases were absent. Hilar lesions were less likely to express MUC1, but this was not statistically significant. Fifteen of 25 cases had metastatic disease. Extensive MUC3 expression was significantly associated with well-differentiated tumors, whilst there was an approaching significance between the extensive expression of MUC1 and metastasis in cholangiocarcinoma. 相似文献
992.
Pamela P. W. Lee Tong-Xin Chen Li-Ping Jiang Koon-Wing Chan Wanling Yang Bee-Wah Lee Wen-Chin Chiang Xiang-Yuan Chen Susanna F. S. Fok Tsz-Leung Lee Marco H. K. Ho Xi-Qiang Yang Yu-Lung Lau 《Journal of clinical immunology》2010,30(1):121-131
Introduction
X-linked agammagobulinemia (XLA) is a primary immunodeficiency disorder caused by Bruton's tyrosine kinase (Btk) gene mutation. Recent studies suggested genotype-phenotype correlation in XLA, but a definitive association remains controversial.Patients and Methods
We examined the relationship between specific Btk gene mutations and severity of clinical presentation in 62 patients with XLA. Disease severity was assessed by the age of disease onset and the presence of severe infections, while mutations were classified into severe and mild based on structural and functional consequence by bioinformatics analysis.Results
Fifty-six Btk mutations were identified in 62 patients from 57 kindreds. Variation in phenotypes was observed, and there was a tendency of association between genotype and age of disease onset as well as occurrence of severe infections.Conclusion
A critical analysis of the circumstances upon presentation also revealed that under-recognition of recurrent infections and relevant family history are important hurdles to timely diagnosis of XLA. 相似文献993.
994.
995.
Adhesive proteins existing in the extracellular matrix (ECM) play important roles in the regulation of neuronal cell behavior, including cell adhesion, motility and neurite outgrowth. Herein we show the effects of a series of adhesive proteins on the neurite outgrowth of PC12 cells and elucidate that this is closely related to the activation of focal adhesion kinase (FAK). For this we prepared culture substrates by coating tissue culture plastic with either collagen (Col), fibronectin (FN) or laminin (LN) and investigated the neurite outgrowth behavior. The results demonstrated that neurite outgrowth was highly dependent on the particular type of adhesive protein. While neurite number was comparable on all the coated surfaces, the length of neurites was greater on the FN- and LN-coated ones (greatest on the LN-coated one). In particular, FAK expression was highly up-regulated in the FN- and LN-coated surfaces, as revealed by Western blot analysis. A knock-down experiment further supported the idea that neurite outgrowth was largely suppressed in cells transfected with a FAK knock-down gene. Taken together, the neurite outgrowth of PC12 cells was greatly affected by adhesive proteins of the ECM, particularly FN and LN, and this is considered to be closely related to FAK intracellular signaling. This study may be useful in the consideration and design of nerve guidance and three-dimensional scaffolds which are appropriate to promote neuronal growth and nerve tissue regeneration. 相似文献
996.
J Jung SH Ko do Y Yoo JY Lee YJ Kim SM Choi KK Kang HJ Yoon H Kim J Youn JM Kim 《Immunology》2012,137(1):98-113
5,7-Dihydroxy-3',4',6'-trimethoxyflavone (eupatilin), the active pharmacological ingredient from Artemisia asiatica Nakai (Asteraceae), is reported to have a variety of anti-inflammatory properties in intestinal epithelial cells. However, little information is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelial inflammation. This study investigates the role of eupatilin in the adhesion of inflammatory cells such as monocytes and eosinophils to bronchial epithelial cells. Stimulation of a human bronchial epithelial cell line (BEAS-2B) with tumour necrosis factor-α (TNF-α) increased the expression of surface adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in which eupatilin significantly inhibited the expression of those adhesion molecules in a dose-dependent manner. Eupatilin suppressed the TNF-α-induced activation of IκBα and nuclear factor-κB (NF-κB) signals in BEAS-2B cells. The IκB kinase (IKK) activation was also significantly reduced in eupatilin-pre-treated BEAS-2B and primary normal human bronchial epithelial (NHBE) cells. However, eupatilin did not influence AP-1 activity in TNF-α-stimulated cells. Suppression of NF-κB signalling induced by eupatilin resulted in the inhibition of the expression of adhesion molecules and the adhesion of monocytes and eosinophils to BEAS-2B cells. Furthermore, eupatilin suppressed the phosphorylation of Akt in TNF-α-stimulated BEAS-2B and NHBE cells, leading to down-regulation of NF-κB activation and adhesion molecule expression and finally to suppression of the inflammatory cell adhesion to epithelial cells. These results suggest that eupatilin can inhibit the adhesion of inflammatory cells to bronchial epithelial cells via a signalling pathway, including activation of Akt and NF-κB, as well as expression of adhesion molecules. 相似文献
997.
Cimino-Mathews A Hicks JL Illei PB Halushka MK Fetting JH De Marzo AM Park BH Argani P 《Human pathology》2012,43(7):1003-1011
Androgen receptor (AR) is expressed in approximately 70% of primary breast carcinomas (PBCs) and is a promising therapeutic target for metastatic breast carcinoma (MBC). Here, we examine AR expression in a population of initial surgically resected metastases and a separate cohort of end-stage metastases harvested at autopsy compared with their matched PBCs. Tissue microarrays of matched PBC and MBC were labeled by immunohistochemistry for AR, estrogen receptor (ER), progesterone receptor (PR), and Her2 and classified into the following previously described categories: luminal (ER/PR+/Her2-), triple negative (ER/PR/Her2-), Her2 (ER/PR-/Her2+), and luminal loss (ER/PR loss from primary to metastasis). In the cohort of surgically resected metastases (n = 16), AR was expressed in 12 of 16 PBC and maintained in 11 of 12 corresponding MBCs. Of these, 36% showed stronger AR labeling in the metastases and none showed a decrease. In the cohort of metastases harvested at autopsy (n = 16), AR was expressed in 11 of 16 primary carcinomas and maintained in only 5 of 11 corresponding metastases. Of these, none showed increased AR and 80% showed decreased AR labeling. AR expression is overwhelmingly concordant between matched PBC and MBC at initial presentation. These findings validate AR as a therapeutic target in MBC and suggest that AR may need to be reevaluated in metastases even if the primary is negative. However, similar to ER/PR, AR expression is often decreased with a trend toward complete loss in end-stage metastases, suggesting a shift of AR expression between initial and end-stage metastases. This suggests an opportunity for targeted antiandrogen therapy at an earlier stage of disease progression. 相似文献
998.
Meyerson HJ Blidaru G Edinger A Osei E Schweitzer K Fu P Ho L 《American journal of clinical pathology》2012,137(1):39-50
Neuropilin-1 (NRP-1)/CD304 is a marker for plasmacytoid dendritic cells. We determined the distribution of NRP-1/CD304 expression on normal hematopoietic cells and in 167 acute leukemias by flow cytometry. NRP-1/CD304 surface expression was frequent in precursor B-cell acute lymphoblastic leukemia (36/51 [71%]) and uncommon in acute myeloid leukemia (22.9%). In acute myeloid leukemia, expression was noted in all (4/4) acute myeloid leukemias with the M4eo subtype and in 50% of specimens (6/12) with complex cytogenetics. On hematopoietic cells, NRP-1/CD304 was expressed on normal erythroid progenitors, plasma cells, and B-cell progenitors, as well as plasmacytoid dendritic cells. Expression was not consistently detected on other hematopoietic cell types. Owing to this distribution of expression, the detection of NRP-1/CD304 alone on a hematopoietic cell cannot be used to determine plasmacytoid dendritic cell differentiation. Finally, we show that NRP-1/CD304 is overexpressed in 30% of precursor B-cell acute lymphoblastic leukemia samples compared with normal B-cell progenitors, allowing for its potential use as a marker for the detection of minimal residual disease. 相似文献
999.
Objective
The aim of this study was to determine whether three specific interleukin-10 (IL-10) polymorphisms confer susceptibility to psoriasis.Methods
A meta-analysis was conducted on the associations between the IL-10-1082 G/A, -592 C/A polymorphisms and haplotypes of the IL-10-1082 G/A, -592 C/A, -819 C/T polymorphisms and psoriasis.Results
A total of eight studies involving 1,018 psoriasis patients and 1,186 controls were considered in the meta-analysis. No association was found between psoriasis and the IL-10-1082 G allele in all study subjects [odds ratio (OR)?=?1.098, 95?% confidence interval (CI)?=?0.923?1.306, p?=?0.291] or between this allele and psoriasis in Europeans (OR?=?0.990, 95?% CI?=?0.809?1.214, p?=?0.925), but a significant association was found in Asians (OR?=?1.785, 95?% CI?=?1.144?2.76, p?=?0.011). Three polymorphisms at the promoter region of IL-10 (-1082 G/A, -819 C/T, -592 C/A) are known to be in complete linkage disequilibrium, but no association was found between the haplotype and psoriasis.Conclusions
This meta-analysis shows that the IL-10-1082 G/A polymorphism confers susceptibility to psoriasis in Asians, and suggests that the IL-10 promoter -1082 polymorphism has an ethnicity-specific effect. 相似文献1000.
Kett LR Boassa D Ho CC Rideout HJ Hu J Terada M Ellisman M Dauer WT 《Human molecular genetics》2012,21(4):890-899
Dominant missense mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common genetic causes of Parkinson disease (PD) and genome-wide association studies identify LRRK2 sequence variants as risk factors for sporadic PD. Intact kinase function appears critical for the toxicity of LRRK2 PD mutants, yet our understanding of how LRRK2 causes neurodegeneration remains limited. We find that most LRRK2 PD mutants abnormally enhance LRRK2 oligomerization, causing it to form filamentous structures in transfections of cell lines or primary neuronal cultures. Strikingly, ultrastructural analyses, including immuno-electron microscopy and electron microscopic tomography, demonstrate that these filaments consist of LRRK2 recruited onto part of the cellular microtubule network in a well-ordered, periodic fashion. Like LRRK2-related neurodegeneration, microtubule association requires intact kinase function and the WD40 domain, potentially linking microtubule binding and neurodegeneration. Our observations identify a novel effect of LRRK2 PD mutations and highlight a potential role for microtubules in the pathogenesis of LRRK2-related neurodegeneration. 相似文献