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991.
Oh JE Kook JK Park KH Lee G Seo BM Min BM 《International journal of molecular medicine》2003,11(4):491-498
Serial subculture of primary normal human oral keratinocytes (NHOKs) to the post-mitotic stage induces terminal differentiation, which is in part linked to elevated levels of phospholipase C (PLC)-gamma1. Therefore, PLC-gamma1 may be involved in the signal transduction system that leads to the calcium regulation of subculture-induced keratinocyte differentiation. To test this hypothesis, the expression of PLC-gamma1 in primary NHOKs was blocked by transfecting cells with the antisense PLC-gamma1 cDNA construct. These cells demonstrated dramatic reductions in PLC-gamma1 protein and in the differentiation markers involucrin and transglutaminase following calcium exposure and an increase (15-20%) in in vitro life span versus empty vector-transfected cells. In addition, we established the ability of antisense PLC-gamma1 to block the serial subculture-induced rise in intracellular calcium. Similar observations were made following treatment with the specific PLC inhibitor U73122. These results indicate that the terminal differentiation of NHOKs by serial subculture is associated with PLC-gamma1, which mediates calcium regulation by mobilizing intracellular calcium. 相似文献
992.
Gonadotrophin stimulation of donor females decreases post-implantation viability of cultured one-cell hamster embryos 总被引:1,自引:4,他引:1
Hamster one-cell embryos were collected from two groups of donors: females
that were super-stimulated with pregnant mare's serum gonadotrophin (PMSG)
and females that were not. Embryos were cultured for 72 h and scored for
development. Morulae and blastocysts from the PMSG- and non-stimulated
females were transferred into contralateral uterine horns of non-stimulated
recipient females, so that experimental embryos (from PMSG-stimulated
females) and control embryos (from non- stimulated females) were paired
within a single recipient. Right and left uterine horns of recipient
females were examined 11 days later for the number of implantation sites
and fetuses. After 72 h of culture, development to morulae and blastocysts
was not significantly different for embryos from PMSG- and non-stimulated
females. However, embryos from PMSG-stimulated females compared to controls
had significantly reduced mean cell numbers (18 versus 21; P=0.003) and a
two-fold decrease in viability post-transfer (20 versus 45%; P=0.02). These
findings indicate that gonadotrophin stimulation compromises subsequent
developmental competence either during oocyte maturation or in the very
early embryo, but it is unclear whether reduced viability is a direct
effect or is an indirect consequence of PMSG stimulation.
相似文献
993.
Comparison of epigenetic and genetic alterations in mucinous cystic neoplasm and serous microcystic adenoma of pancreas. 总被引:4,自引:0,他引:4
Sang Geol Kim Tsung-Teh Wu Jae Hyuk Lee Young Kook Yun Jean-Pierre Issa Stanley R Hamilton Asif Rashid 《Modern pathology》2003,16(11):1086-1094
Mucinous cystic neoplasms and serous microcystic adenomas account for the majority of cystic tumors of pancreas. Mucinous cystic neoplasms and serous microcystic adenomas have different frequencies of progression to malignancy. The genetic and epigenetic alterations of these tumors have not been studied in detail. In this study, we compared methylation status of p16, p14, VHL, and ppENK genes by methylation-specific PCR (MSP), and genetic alterations including K-ras and beta-catenin gene mutations, chromosome 3p loss, and microsatellite instability in 15 mucinous cystic neoplasms (10 benign and 5 borderline) and 16 serous microcystic adenomas. There were no significant differences between mucinous cystic neoplasms and serous microcystic adenomas in methylation of p16 (14%, 2/14 and 12%, 2/16), p14 (15%, 2/13 and 37%, 6/16), VHL (0/14 and 7%, 1/14), and ppENK (0/14 and 0/13), respectively. K-ras mutation was present only in mucinous cystic neoplasms but not in serous microcystic adenomas (33%, 5/15 versus 0/16; P =.004). In addition, LOH at 3p25, the chromosomal location of VHL gene, was present in 57% (8/14) of serous microcystic adenomas compared with in 17% (2/12) of mucinous cystic neoplasms (P =.03). No beta-catenin mutation, microsatellite instability, or mutation of transforming growth factor beta type II receptor was present in either type of tumors. In conclusion, K-ras mutations and allelic loss of VHL locus at 3p25, but not methylation, distinguished mucinous cystic neoplasms and serous microcystic adenomas. The differences in genetic alterations but not epigenetic alterations may explain the pathogenesis and progression to malignancy of these cystic tumors of pancreas. 相似文献
994.
0 引言 我科 1985 / 1999- 10心脏手术前住院死亡患者 35例 ,我们从死亡原因分析和经验教训中提出护理对策 .1 临床资料 本组 35例 :婴幼儿先天性心脏病 12例 ,其中法乐四联症 2例 , 型永存动脉干 1例 ,右室双出口 +肺动脉狭窄 1例 ,主动脉弓离断 1例 ,房缺 +室缺 +动脉导管未闭 +肺动脉高压 1例 ,室缺 +右下肺包块 1例 ,主动脉狭窄 +扩张型心肌病 1例 ,室缺 +动脉导管 1例 ,室缺 +严重肺动脉高压2例 ,室缺 +瓦氏窦瘤破裂 1例 .风湿性心脏病 18例 :其中 9例为重度主动脉关闭不全 ,3例为重度二尖瓣关闭不全伴大量腹水 ,3例为重度主动脉关… 相似文献
995.
Chorioretinal response to intravitreal aflibercept injection in acute central serous chorioretinopathy 下载免费PDF全文
AIM: To evaluate chorioretinal responses to intravitreal aflibercept injection (IAI) in patients with acute central serous chorioretinopathy (CSC).
METHODS: Seventy-one eyes from 71 patients with symptomatic CSC for less than six months were included. Thirty-five eyes received a single IAI and 36 eyes were observed without treatment. Best-corrected visual acuity (BCVA), central subfield foveal thickness (CSFT), and subfoveal choroidal thickness (SFCT) were assessed at baseline and at 1, 2, and 3mo.
RESULTS: The mean SFCT in the IAI group decreased at 1mo, rebounded at 2mo and remained stable at 3mo compared to the baseline, while significant change was not noted in the observation group. The mean CSFT decreased significantly during the 3-month study period in both groups, and was significantly lower in the IAI group at 1mo (P<0.001). A rebound of CSFT between 1 and 2mo was noted in 14 eyes (40.0%) in the IAI group and in 1 eye (2.8%) in the observation group (P<0.001). The significant visual improvement was achieved from 1mo in the IAI group, and from 2mo in the observation group. The rate of complete absorption of subretinal fluid at 3mo did not differ between the two groups. (45.7% vs 41.7%, P=0.813).
CONCLUSION: A single IAI for acute CSC induce a transient decrease in SFCT and CSFT, which implies that IAI may have a pharmacological effect on the underlying hyperpermeable choroid in acute CSC. 相似文献
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