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101.
目的:通过检测人绒癌细胞株Be Wo合体化过程中增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、生存素(Survivin)蛋白表达的变化,探讨滋养细胞合体化后增殖性的变化,为恶性滋养细胞肿瘤,尤其是耐药恶性滋养细胞肿瘤的临床治疗提供新的思路和方法。方法:利用毛喉素(forskolin)诱导Be Wo细胞株融合;应用逆转录聚合酶链反应(RT-PCR)检测促融素(Syncytin)在forskolin作用不同时间的Be Wo细胞株中的表达;应用蛋白质印迹(Western blotting)检测PCNA、Survivin蛋白在forskolin作用不同时间的Be Wo细胞株中的表达;应用噻唑蓝比色分析实验(MTT)法检测forskolin作用不同时间的绒癌细胞株Be Wo的增殖能力。结果:1forskolin作用后的Be Wo细胞株Syncytin基因的表达增强,且随着forskolin作用时间的延长,Syncytin的表达更强,于48 h达到高峰。2forskolin作用后的Be Wo细胞株PCNA、Survivin蛋白的表达降低。3forskolin作用后的Be Wo细胞株的增殖能力下降,且不同作用时间的差异有统计学意义;forskolin作用的时间越长,Be Wo细胞株增殖能力下降越明显。结论:人绒癌细胞株Be Wo合体化后PCNA、Survivin蛋白的表达降低,说明人绒癌细胞株Be Wo合体化后增殖性降低,推测诱导滋养细胞合体化可能对临床治疗恶性滋养细胞肿瘤具有一定作用。  相似文献   
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Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway.  相似文献   
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ObjectiveThe beneficial effects of carnitine supplementation on nonalcoholic fatty liver disease are unclear. We conducted a systematic review and meta-analysis to evaluate the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance in patients with nonalcoholic fatty liver disease.MethodsA comprehensive search of PubMed, Web of Science, Scopus, Cochrane Library, and Google Scholar databases were performed. Only randomized placebo-controlled human studies that examined the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance up to September 2019 were included. Fixed effects or random-effects models were applied to compute the pooled effect size. Heterogeneity assessments were performed using Cochran’s Q test and I-squared statistics. The quality of the studies was assessed using the Jaded scale.ResultsA total of 5 articles were selected, including 334 individuals (167 in control and 167 in intervention groups). The results demonstrated that carnitine supplementation significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: −0.91; 95 % CI: −1.11, −0.72; p < 0.001, I2 = 0.0 %) and the levels of aspartate aminotransferase (AST) (WMD: −16.62; 95 % CI: −28.11, −5.14; IU/l; p = 0.005, I2 = 93.5 %), alanine aminotransferase (ALT) (WMD: -33.39; 95 % CI: −45.13, −21.66; IU/l; p < 0.001, I2 = 93.4 %), and triglycerides (TG) (WMD: −22.13; 95 % CI: −38.91, −5.34; mg/dl; p = 0.01; I2 = 0.0 %). However, the results of the pooled effect size did not show any significant effect of carnitine supplementation on body mass index (BMI) (WMD: 0.07; 95 % CI: −0.15, 0.29; p = 0.55; I2 = 0.0 %), body weight (WMD: −0.28; 95 % CI: −2.23, 1.68; p = 0.78; I2 = 45.7 %), the levels of gamma-glutamyl transferase (γGT) (WMD: −11.31; 95 % CI: −24.35, 1.73; IU/l; p = 0.09, I2 = 61.1 %), cholesterol (WMD: −13.58; 95 % CI: −46.77, 19.60; mg/dl; p = 0.42; I2 = 94.9 %), high-density lipoprotein-cholesterol (HDL-C) (WMD: 1.36; 95 % CI: −0.96, 3.68; mg/dl; p = 0.25; I2 = 64.7 %), and low density lipoprotein-cholesterol (LDL-C) (WMD: −14.85; 95 % CI: −45.43, 15.73; mg/dl; p = 0.34; I2 = 96.4 %).ConclusionsThis analysis shows that carnitine supplementation for patients with nonalcoholic fatty liver disease demonstrates a reduction in AST, ALT, TG levels and HOMA-IR. However, no significant effect of carnitine supplementation was observed on BMI, body weight, the levels of γGT, TC, HDL-cholesterol and LDL-cholesterol.  相似文献   
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《Neuro-Chirurgie》2022,68(2):196-201
BackgroundTumor-to-tumor metastases are extremely rarely reported lesions, which usually involve an indolent lesion hosting a more aggressive neoplasm. We present an unusual initial manifestation of a previously unknown clear cell renal cell carcinoma as a tumor-to-tumor metastasis in a typical meningothelial meningioma.Case reportA 73-year old patient with transient left slight monoparesis was addressed to our Neurosurgical Department after being evaluated by his general practitioner and passing a cerebral MRI which revealed a right frontotemporal mass attached to the meninge. At presentation, no deficits were identified; therefore an elective surgery was proposed. Histological analysis revealed a typical meningothelial meningioma containing a metastatic clear cell renal cell carcinoma. Additional thoraco-abdominal computer tomography identified a 6 cm diameter lesion within the right kidney with radiological features highly suggestive of a primary clear cell renal cell carcinoma.ConclusionOur case highlights the need for a specialized neuropathological approach to clinical and imagistic indolent meningiomas, as they may require important differential diagnosis that can highly impact the treatment and follow-up of brain tumor patients.  相似文献   
107.
Urothelial cell carcinoma (UCC) of the bladder is one of the most common malignancies, causing considerable morbidity and mortality worldwide. It is unique among the epithelial carcinomas as two distinct pathways to tumourigenesis appear to exist: low grade, recurring papillary tumours usually contain oncogenic mutations in FGFR3 or HRAS whereas high grade, muscle invasive tumours with metastatic potential generally have defects in the pathways controlled by the tumour suppressors p53 and retinoblastoma. Over the last two decades, a number of transgenic mouse models of UCC, containing deletions or mutations of key tumour suppressor genes or oncogenes, have helped us understand the mechanisms behind tumour development. In this summary, I present my work investigating the role of the WNT signalling cascade in UCC.  相似文献   
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