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141.
Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication. 相似文献
142.
The IGF system is one of the most important endocrine and paracrine growth factor systems that regulate fetal and placental growth, whereas the liver is the principal source of circulation IGF-I. In the present study, expression of IGF-I, IGF type-I receptor (IGF-IR), and IGF binding protein (IGFBP)-3 genes was quantified by RT-PCR in the liver tissue on days 13, 17, 21, 25, and 27 of embryonic development, as well as at 7 days post-hatching (PH) in meat-type Gaoyou ducks and egg-type Jinding ducks. The results showed that IGF-I mRNA could be detected as early as on E 13d, but the expression level was low throughout embryonic development before increasing dramatically by E 27d and 7 days PH in both duck breeds. However, Gaoyou ducks exhibited higher IGF-I mRNA level than Jinding ducks, and the differences were significant on E 13d, E 21d, and at 7 days PH. Expression of IGF-IR in liver increased gradually in the former stages of the embryonic development, reaching its highest point on E 21d, and then declined up until 7 days PH. The expression pattern of IGFBP-3 gene was similar to that of IGF-IR gene, increasing significantly from E 17d. The expression peak appeared on E 25d, then declined significantly just prior to hatching (day 27) and was followed by an increase at 7 days PH. In general, the expression level of IGF-IR and IGFBP-3 genes in Jinding ducks was higher than that in Gaoyou ducks. Inverse relationships were observed for the expression of IGF-I and IGF-IR, and IGF-I and IGFBP-3, whereas a positive relationship was observed for the expression of IGF-IR and IGFBP-3. Our data indicate a differential expression of selected genes that comprise the IGF system in the duck liver tissue during embryonic and early PH growth and development. 相似文献
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144.
Lei Wang Jie Zheng Yanzhong Luo Tao Xu Qiuxue Zhang Lan Zhang Miaoyun Xu Jianmin Wan Ming‐Bo Wang Chunyi Zhang Yunliu Fan 《Plant biotechnology journal》2013,11(8):997-1005
Long hairpin RNA (hpRNA) transgenes are a powerful tool for gene function studies in plants, but a genomewide RNAi mutant library using hpRNA transgenes has not been reported for plants. Here, we report the construction of a hpRNA library for the genomewide identification of gene function in rice using an improved rolling circle amplification‐mediated hpRNA (RMHR) method. Transformation of rice with the library resulted in thousands of transgenic lines containing hpRNAs targeting genes of various function. The target mRNA was down‐regulated in the hpRNA lines, and this was correlated with the accumulation of siRNAs corresponding to the double‐stranded arms of the hpRNA. Multiple members of a gene family were simultaneously silenced by hpRNAs derived from a single member, but the degree of such cross‐silencing depended on the level of sequence homology between the members as well as the abundance of matching siRNAs. The silencing of key genes tended to cause a severe phenotype, but these transgenic lines usually survived in the field long enough for phenotypic and molecular analyses to be conducted. Deep sequencing analysis of small RNAs showed that the hpRNA‐derived siRNAs were characteristic of Argonaute‐binding small RNAs. Our results indicate that RNAi mutant library is a high‐efficient approach for genomewide gene identification in plants. 相似文献
145.
Yufeng Cheng Qian Wang Zhanjie Li Jianmin Cui Shengwu Hu Huixian Zhao Mingshun Chen 《PloS one》2013,8(11)
Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility in rapeseed (Brassica napus L.). To understand MES-induced male sterility in rapeseed better, comparative cytological and proteomic analyses were conducted in this study. Cytological analysis indicated that defective tapetal cells and abnormal microspores were gradually generated in the developing anthers of MES-treated plants at various development stages, resulting in unviable microspores and male sterility. A total of 141 differentially expressed proteins between the MES-treated and control plants were revealed, and 131 of them were further identified by MALDI-TOF/TOF MS. Most of these proteins decreased in abundance in tissues of MES-treated rapeseed plants, and only a few increased. Notably, some proteins were absent or induced in developing anthers after MES treatment. These proteins were involved in several processes that may be crucial for tapetum and microspore development. Down-regulation of these proteins may disrupt the coordination of developmental and metabolic processes, resulting in defective tapetum and abnormal microspores that lead to male sterility in MES-treated plants. Accordingly, a simple model of CHA-MES-induced male sterility in rapeseed was established. This study is the first cytological and dynamic proteomic investigation on CHA-MES-induced male sterility in rapeseed, and the results provide new insights into the molecular events of male sterility. 相似文献
146.
IGFBP3, a Transcriptional Target of Homeobox D10, Is Correlated with the Prognosis of Gastric Cancer
Meng Xue Yanfei Fang Guoming Sun Wei Zhuo Jing Zhong Cuijuan Qian Lan Wang Liangjing Wang Jianmin Si Shujie Chen 《PloS one》2013,8(12)
Homeobox D10 (HoxD10) plays important roles in the differentiation of embryonic cells and progression of breast cancer. Our previous report revealed that insulin-like growth factor binding protein-3 (IGFBP3) was regulated by HoxD10 in gastric cancer cells; however, the functional roles and underlying mechanisms of IGFBP3 in gastric cancer remain unclear. Here, we found that the expression of IGFBP3 were upregulated after ectopic expression of HoxD10 in gastric cancer cells. Chromatin immunoprecipitation assay showed that HoxD10 bound to three potential regions of IGFBP3 promoter. Exogenous HoxD10 significantly enhanced the activity of luciferase reporter containing these binding regions in gastric cancer cells. Further data showed that all of these binding sites had Hox binding element “TTAT”. Immunohistochemical staining results revealed that IGFBP3 expression was significantly downregulated in 86 gastric adenocarcinomas tissues relative to their adjacent non-cancerous tissues (p<0.001). Moreover, IGFBP3 expression was significantly lower in gastric tumor with lymph node metastasis compared with that without lymph node metastasis (p=0.045). Patients with high expression level of IGFBP3 showed favorable 5 year overall survival (p=0.011). Knockdown of IGFBP3 accelerated gastric cancer cell migration and invasion and induced the expression of invasive factors including MMP14, uPA and uPAR. Thus, our data suggest that HoxD10-targeted gene IGFBP3 may suppress gastric cancer cell invasion and favors the survival of gastric cancer patients. 相似文献
147.
148.
目的:探讨腹腔镜卵巢囊肿剥除术中采用序贯式止血法对卵巢功能的影响。方法:将100例行腹腔镜卵巢囊肿剥除术患者按照抽签法随机地均分为对照组与观察组,对照组给予传统双极电凝治疗,观察组采取序贯式止血法,靠近卵巢门的髓质出血镜下缝合,远离卵巢门行皮质渗血电凝处理。比较两组患者手术前后雌二醇(Estradiol,E2)、促卵泡激素(Follicle-stimulating hormonc,FSH)、促黄体生成素(Luteotropic hormone,LH)及围绝经期综合征发生情况。结果:对照组术前与术后3个月及术后6个月E2、FSH及LH差异均具有统计学意义,观察组手术前后激素水平差异无统计学意义,且观察组术后与对照组术后上述指标差异均具有统计学意义;对照组患者术后月经紊乱、植物神经功能紊乱的发生率分别为14.00%与12.00%,观察组为2.00%及0%,两组差异具有显著的统计学意义。结论:序贯式止血法应用于腹腔镜卵巢囊肿剥除术中影响卵巢功能,效果显著,值得在临床上加以推广并应用。 相似文献
149.
目的:探讨胃癌外周血中树突状细胞CD83+表达对预后的影响及意义。方法:选取2010年1月至2011年6月间我科收治的胃癌病人74例进行分析,均为原位癌或仅有局部淋巴结转移,以外周血树突状细胞CD83+为研究对象,以术后生存时间为标准,对病人手术预后进行分析。结果:所选74例病人术后3周测得外周血树突状细胞CD83+表达频数平均值(7.32+1.88脚,以表达频数中位数7.32%为标准将74例病人分为高频组和低频组两组,每组37人。术后总体生存时间108周-413周,平均生存时间(207+227)周,其中高值组平均生存时间(247+121)周,低值组平均生存时间(118+54)周,两组生存时间具有明显差别(P〈O.05)。结论:胃癌外周血中树突状细胞CD83+的表达对接受手术病人预后有重要影响,可以作为判断病人预后的参考依据,对预后不良者加以对症及时干预以降低死亡率。 相似文献
150.
目的:胰腺癌恶性程度高、进展快、预后差,姜黄素对于抑制恶性肿瘤的发生和进程具有广泛的生物学效应。但姜黄素能否诱导人胰腺癌细胞凋亡,其具体作用机制如何?目前仍无报道。本研究拟观察姜黄素对人胰腺癌PANC.1细胞凋亡的影响,探讨姜黄素诱导PANC.1细胞凋亡的机制。方法:不同浓度姜黄素处理人胰腺癌PANC-1细胞,流式细胞仪检测PANC-1细胞凋亡率,并分析Caspase-9和Caspase-3活性的变化,同时通过RT—PCR和Westemblot分析PANC-1细胞中P53表达的变化。结果:PANC-1细胞经不同浓度的姜黄素处理后,可以显著诱导细胞凋亡,并呈现一定的剂量依赖性,提示姜黄素具有一定抗肿瘤活性。姜黄素能够同时增加Caspase-9和Caspase-3的活性,并呈现一定的剂量依赖性,提示姜黄素可能通过Caspase-9和Caspase-3途径来诱导PANC.1细胞凋亡的发生。RT—PCR和westernblot结果显示,姜黄素可以显著增加PANC-1细胞中P53蛋白表达水平。结论:姜黄素可以显著诱导PANC-1细胞凋亡的发生,提高Caspase-9和Caspase-3的活性,同时增加的P53表达,并呈现一定的剂量依赖性,提示姜黄素诱导PANC-1细胞凋亡的过程可能与增加细胞中Caspase-9,Caspase-3以及P53的表达有关。本研究探讨了姜黄素诱导PANC-1细胞凋亡的分子机制,为姜黄素的进一步应用提供了新的思路和理论支持,在人胰腺癌的临床治疗中具有一定的潜在应用价值。 相似文献