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51.
AM Hanash JA Dudakov G Hua MH O'Connor LF Young NV Singer ML West RR Jenq AM Holland LW Kappel A Ghosh JJ Tsai UK Rao NL Yim OM Smith E Velardi EB Hawryluk GF Murphy C Liu LA Fouser R Kolesnick BR Blazar MR van den Brink 《Immunity》2012,37(2):339-350
Little is known about the maintenance of intestinal stem cells (ISCs) and progenitors during immune-mediated tissue damage or about the susceptibility of transplant recipients to tissue damage mediated by the donor immune system during graft versus host disease (GVHD). We demonstrate here that deficiency of recipient-derived IL-22 increased acute GVHD tissue damage and mortality, that ISCs were eliminated during GVHD, and that ISCs as well as their downstream progenitors expressed the IL-22 receptor. Intestinal IL-22 was produced after bone marrow transplant by IL-23-responsive innate lymphoid cells (ILCs) from the transplant recipients, and intestinal IL-22 increased in response to pretransplant conditioning. However, ILC frequency and IL-22 amounts were decreased by GVHD. Recipient IL-22 deficiency led to increased crypt apoptosis, depletion of ISCs, and loss of epithelial integrity. Our findings reveal IL-22 as a critical regulator of tissue sensitivity to GVHD and a protective factor for ISCs during inflammatory intestinal damage. 相似文献
52.
Dysfunction in the corneal endothelium, which controls the hydration and transparency of the cornea, is one of the common reasons for transplantation. A tissue-engineered corneal endothelium is of interest for corneal regeneration and for in vitro testing of ocular drugs. In the native environment, corneal endothelial cells interact with the nanotopography of the underlying Descemet's membrane. This study showed that nanotopography enhanced bovine corneal endothelial cell (BCEC) responses, creating a monolayer which resembled the healthy corneal endothelium. Topographies of different geometries were first tested to identify those that would elicit the most significant responses. A BCEC monolayer was then generated on both micro- and nanoscale pillars and wells. The BCEC monolayer cultured on topographies exhibited polygonal geometries with well-developed tight junction proteins. Scanning electron microscopy revealed that cells on pillars showed a higher density of microvilli, which was similar to native corneal endothelium. BCECs on nanopillars displayed a lower coefficient of variation of area (0.31) that was within the range of healthy corneal endothelium. More importantly, a BCEC monolayer cultured on nanopillars also had an enhanced Na(+)/K(+)-ATPase immunofluorescence expression, mRNA upregulation and a higher Na(+)/K(+)-ATPase activity. These results suggest that nanopillar substrate topography may provide relevant topographical cues, which could significantly enhance the formation and function of corneal endothelium. 相似文献
53.
A genotype-independent real-time PCR assay for quantification of hepatitis B virus DNA 总被引:2,自引:0,他引:2 下载免费PDF全文
Accurate quantification of hepatitis B virus (HBV) DNA levels is important for monitoring patients with chronic HBV infection and for assessing their responses to antiviral therapy. This study aimed to develop a real-time PCR assay that is sensitive and can accurately quantify a wide range of HBV DNA levels across the known HBV genotypes. An "in-house" real-time PCR assay using primers and a TaqMan probe in a highly conserved region of the HBV surface gene was designed. The assay was standardized against a WHO standard and validated against plasmids of HBV genotypes A through H. The linear quantification range was approximately 5 x 10(0) to 2.0 x 10(9) IU/ml. Results of samples from patients infected with HBV genotypes A through H tested using our real-time "in-house" PCR assay showed an excellent correlation with those of the Cobas Amplicor HBV Monitor (R2=0.9435) and the Cobas TaqMan HBV (R2=0.9873) tests. We have established a real-time PCR assay that is genotype independent and can accurately quantify a wide range of HBV DNA levels. Further studies of additional samples are ongoing to validate the genotype independence of our assay. 相似文献
54.
Yun H Kim S Lee H Byun KS Kwon SY Yim HJ Lim YS Jeong SH Jee Y 《Journal of medical virology》2008,80(5):777-784
Hepatitis A virus (HAV) is a causative agent of acute viral hepatitis, which represents a significant public health problem. HAV is usually transmitted by oral-fecal route and prevalent not only in developing countries but also in developed countries worldwide. To characterize the HAV wild type strains circulating in Korea, the VP3/VP1 and VP1/P2A junction regions were detected by RT-PCR from HAV IgM positives during 2005 and 2006. Among 160 HAV IgM positive sera, 30% (n = 48) were positive for HAV RNA. Additionally, the VP3/VP1 junction regions were detected all six stools, which collected from outbreak in Gyeonggi province. Phylogenetic analysis of the sequences obtained from 54 distinct HAV isolates revealed that most of the strains (n = 45) belonged to genotype IA and the others including nine strains belonged to genotype IIIA. Interestingly, a Q --> S amino acid change was dominantly observed at position 810 of the VP1/P2A junction region in 14 isolates. The molecular epidemiology of HAV infection in Korea has changed with the co-circulation of at least two genotypes and 810Q --> S amino acid substitutions were found to be prevalent. These results strongly suggest that various HAV strains, including genotype IIIA, might be imported from high-endemic countries into Korea. 相似文献
55.
Kim HJ Park HJ Jung KH Ban JY Ra J Kim JW Park JK Choe BK Yim SV Kwon YK Chung JH 《Neuroscience letters》2008,430(1):60-63
To further clarify schizophrenia (SCZ), disrupted in schizophrenia 1 (DISC1) is a promising candidate gene expressed predominantly within the hippocampus. Several lines of evidence suggest that DISC1 may be involved in susceptibility to SCZ. In this study, we investigated whether genetic polymorphisms in the coding region of DISC1 were associated with several SCZ clinical phenotypes in a Korean population. To examine any association between DISC1 and SCZ, we genotyped three clinical single nucleotide polymorphisms (SNPs) (rs3738401, R264Q; rs3738402, L465L; rs821616, S704C) in the coding region of the DISC1 gene using the Illumina Sentrix Array Matrix chip and direct sequencing in 303 patients with SCZ and 300 healthy controls. Our case-control analysis showed that none of these SNPs was associated with SCZ. In further endophenotype stratification, however, we found a significant association between rs821616 and the poor concentration subgroup of SCZ, determined using the Operational Criteria Checklist (codominant model, p=0.015). Our results suggest that DISC1 may be a susceptibility gene for poor concentration among Korean patients with SCZ. 相似文献
56.
Petrofsky J Paluso D Anderson D Swan K Yim JE Murugesan V Chindam T Goraksh N Alshammari F Lee H Trivedi M Hudlikar AN Katrak V 《Medical engineering & physics》2011,33(3):325-329
As predicted by the Pennes equation, skin blood flow is a major contributor to the removal of heat from an external heat source. This protects the skin from erythema and burns. But, for a person in a thermally neutral room, the skin is normally much cooler than arterial blood. Therefore, if skin blood flow (BF) increases, it should initially warm the skin paradoxically. To examine this phenomenon, 10 young male and female subjects participated in a series of experiments to examine the contribution of skin blood flow in the initial warming the skin after the application of local heat. Heat flow was measured by the use of a thermode above the brachioradialis muscle. The thermode was warmed by constant temperature water at 44°C entering the thermode at a water flow rate of 100 cm(3)/min. Skin temperature was measured by a thermistor and blood flow in the underlying skin was measured by a laser Doppler imager in single point mode. The results of the experiments showed that, when skin temperature is cool (31-32°C), the number of calories being transferred to the skin from the thermode cannot account for the rise in skin temperature alone. A significant portion of the rise in skin temperature is due to the warm arterialized blood traversing the skin from the core areas of the body. However, as skin temperature approaches central core temperature, it becomes less of a heat source and more of a heat sync such that when skin temperature is at or above core temperature, the blood flow to the skin, as predicted by Pennes, becomes a heat sync pulling heat from the thermode. 相似文献
57.
Yim JH Yoon JH Kim SA Kim WG Jeon MJ Han JM Sung TY Kim TY Kim WB Hong SJ Shong YK Gong G 《Journal of Korean medical science》2011,26(9):1191-1195
X-linked inhibitor of apoptosis protein (XIAP) is associated with tumor genesis, growth, progression and metastasis, and acts by blocking caspase-mediated apoptosis. In the present study, we sought to evaluate the expression patterns of XIAP in various neoplastic thyroid disorders and determine the association between XIAP expression and clinicopathologic factors. Expression of XIAP was evaluated with immunohistochemical staining using monoclonal anti-XIAP in 164 specimens of conventional papillary thyroid carcinoma (PTC) and 53 specimens of other malignant or benign thyroid tumors. XIAP positivity was observed in 128 (78%) of the 164 conventional PTC specimens. Positive rates of XIAP expression in follicular variant PTC, follicular, medullary, poorly differentiated, and anaplastic thyroid carcinoma specimens were 20%, 25%, 38%, 67%, and 38%, respectively. Six nodular hyperplasia specimens were negative and 1 of 7 follicular adenomas (8%) was positive for XIAP. Lateral neck lymph node metastases were more frequent in patients negative for XIAP expression (P = 0.01). Immunohistochemical staining for XIAP as a novel molecular marker may thus be helpful in the differential diagnosis of thyroid cancer. Moreover, high XIAP expression in conventional PTC is strongly associated with reduced risk of lateral neck lymph node metastasis. 相似文献
58.
Li Lou Shu Wei Liu Zhen Mei Zhao Pheng Ann Heng Yu Chun Tang Zheng Ping Li Yong Ming Xie Yim Pan Chui 《Surgical and radiologic anatomy : SRA》2009,31(10):763-768
Three-dimensional (3D) reconstruction of intrahepatic vessels is very useful in visualizing the complex anatomy of hepatic
veins and intrahepatic portal vein. It also provides a 3D anatomic basis for diagnostic imaging and surgical operation on
the liver. In the present study, we built a 3D digitized model of hepatic veins and intrahepatic portal vein based on the
coronal sectional anatomic dataset of the liver. The dataset was obtained using the digital freezing milling technique. The
pre-reconstructed structures were identified and extracted, and then were segmented by the method of manual intervention.
The digitized model of hepatic veins and intrahepatic portal vein was established using 3D medical visualization software.
This model facilitated a continuous and dynamic displaying of the hepatic veins and intrahepatic portal vein at different
orientations, which demonstrated the complicated relationship of adjacent hepatic veins and intrahepatic portal vein realistically
in the 3D space. This study indicated that high-quality 2D images, precise data segmentation, and suitable 3D reconstruction
methods ensured the reality and accuracy of the digital visualized model of hepatic veins and intrahepatic portal vein. 相似文献
59.
Objective
To evaluate the impact of both pretreatment thrombocytosis, and platelet count reduction post-adjuvant chemotherapy, on survival in patients with advanced epithelial ovarian cancer.Methods
Records of 179 women who underwent cytoreductive surgery for FIGO stage III or IV epithelial ovarian cancer and received six cycles of platinum/paclitaxel-based chemotherapy between July1998 and March 2009 were retrospectively reviewed. Platelet ratio was defined as the preoperative platelet count divided by the platelet count after chemotherapy. The prognostic significance of thrombocytosis and platelet ratio, together with various clinicopathological factors, were evaluated by multivariate analysis.Results
Sixty-two of 179 (34.6%) patients had thrombocytosis at primary diagnosis. Patients with preoperative thrombocytosis had greater elevations of CA-125 (p < 0.0001) and a greater volume of ascites (p = 0.007). On multivariate analysis, thrombocytosis and CA-125 elevation retained significance as indicators of poor prognosis in patients with stage III or IV disease. In patients with normal CA-125 after chemotherapy, a high platelet ratio was an independent risk factor for reduced survival (p = 0.05).Conclusions
Preoperative thrombocytosis and a high platelet ratio appear to be poor prognostic factors of survival in patients with advanced epithelial ovarian cancer who were treated with cytoreductive surgery and adjuvant platinum/paclitaxel-based chemotherapy. 相似文献60.
Seon-Cheol Park Sang-Woo Hahn Tae-Yeon Hwang Jae-Min Kim Tae-Youn Jun Min-Soo Lee Jung-Bum Kim Hyeon-Woo Yim Yong Chon Park 《Yonsei medical journal》2014,55(6):1712-1720