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51.
Fetal alcohol syndrome (FAS) is characterized by growth retardation, craniofacial malformations, and heart and neural defects; the cellular and molecular mechanism(s) responsible for ethanol's teratogenicity remains unknown. Although the phenotype suggests that prenatal ethanol exposure perturbs neural crest cell development, direct proof that these cells are an in utero target is still lacking. Previous research suggested that cranial neural crest cells are eliminated by ethanol-induced apoptosis. We tested this hypothesis using a chick embryo model of FAS. A single dose of ethanol, chosen to achieve a concentration of 35–42 mg/dl, was injected in ovo at gastrulation and resulted in growth retardation, craniofacial foreshortening, and disrupted hindbrain segmentation. Ethanol exposure enhanced cell death within areas populated by cranial neural crest cells, particularly in the hindbrain and craniofacial mesenchyme. In contrast, control embryos had limited cell death within these regions. Subsequent immunolabeling with neural crest cell-specific antibody revealed that ethanol treatment resulted in fewer neural crest cell numbers, whereas neural crest migration patterns were unaffected by ethanol. These results suggest that prenatal ethanol exposure leads to loss of cranial neural crest cells. Such a loss could result, in part, in the phenotype characteristic of FAS.  相似文献   
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目的研究索拉非尼联合国产程序性细胞死亡受体-1(programmed cell death receptor-1,PD-1)抑制剂在不可手术切除的肝细胞癌(hepatocellular carcinoma, HCC)中的疗效及不良反应。方法回顾性分析2019年6月至2021年1月于北京地坛医院肿瘤内科使用国产PD-1抑制剂联合索拉非尼治疗的不可手术切除的HCC患者的临床资料,资料完整且符合入组条件者共22例,其中卡瑞利珠单抗联合索拉非尼组9例,信迪利单抗联合索拉非尼组13例,随访患者,主要研究终点为统计客观缓解率(objective response rate, ORR)、疾病控制率(disease control rate, DCR)和无进展生存期(progression-free survival, PFS),次要研究终点为总生存期(overall survival, OS)和安全性。结果在可评价疗效的22例患者中,7例患者疗效评价为部分缓解(partial remission, PR),10例患者疗效评价为疾病稳定(stable disease, SD),5例患者疗效评价为疾病进展(progressive disease, PD),ORR为31.8%,DCR为77.3%。中位无进展生存期(median progression-free survival, mPFS)为8.0个月(5.4~10.6个月)。不良反应发生率为77.3%,最常见的不良反应为腹泻(27.3%)、手足综合征(22.7%)、转氨酶升高(22.7%)、疲乏(18.2%)。结论索拉非尼联合国产PD-1抑制剂治疗不可手术切除的HCC临床效果显著,不良反应可控,是一种安全、有效的治疗方案。  相似文献   
54.
Summary N-Methyl-N-nitrosourea (MNU) is a potent carcinogen in various sites of experimental animals and induces thymic lymphoma in rats, which has long been hard to induce by any carcinogen. To analyze the action of MNU on thymocytes, DNA strand breaking in thymocytes from the MNU-treated rat and that in MNU-treated cultured thymocytes were assayed. Fluorometric analysis of DNA unwinding (FADU assay), first reported by Birnboim and Jevcak to detect X-ray-induced DNA damage, was modified and applied to detect DNA damage in thymocytes treated with MNU in vitro or in vivo. In the present modified method, cell lysate was admixed with 0.15M sodium hydroxide, and DNA unwinding was processed at pH 12.0 for up to 2 h at 0° C in iced water. Double-stranded DNA remaining after alkaline reaction was detected by binding ethidium bromide and measuring its fluorescence. The severity of DNA damage, both in vivo and in vitro, depended on the MNU concentration. In addition, the sequential survival rate and cell-size distribution of thymocytes treated with MNU in vitro were investigated. A close relationship between the severity of DNA damage and cell death was demonstrated in MNU-treated thymocytes, and DNA damage by a non-cell-killing dose of MNU was detected with this FADU assay. MNU-induced cell death is not programmed as in apoptosis, which is caused in thymocytes physiologically, immunologically and by X-ray irradiation or corticoids.Abbreviations used MNU N-methyl-N-nitrosourea - FADU fluorometric analysis of DNA unwinding - PBS calcium- and magnesium-free phosphate-buffered saline  相似文献   
55.
BackgroundImmunotherapy has achieved excellent results in patients with lung squamous cell carcinoma. However, in which population it can exert the greatest effect is still unknown. Some studies have suggested that its effect is related to the expression level of PD1. Analyzing the relationship between PD1 expression level and genetic differences in lung squamous cell carcinoma patients will be helpful in understanding the underlying causes of this immunotherapy effect and provide a reference for clinical practice.MethodsIn this study, we used RNA-seq, miRNA-seq, methylation array, mutation profiles, and copy number variation data from the TCGA database and RNA-seq data from the GEO database to analyze the distinctive genomic patterns associated with PD1 and PDL1 expression. RNA-seq data from 44 LUSC patients who underwent surgery at Zhongshan Hospital were also included in the study.ResultsAfter grouping LUSC patients according to the expression levels of PD1 and PDL1, we found no significant difference in survival between the two groups. However, 178 genes, including IL-21, KLRC3, and KLRC4, were significantly upregulated in both the TCGA and GEO databases in the high expression group, and there was a precise correlation between gene expression and epigenetic changes in the two groups. At the same time, the overall level of somatic mutations was not significantly different between the two groups. It is worth noting that the gene enrichment results showed that the differential pathways were mainly enriched in immune regulation, especially T cell-related immune activities.ConclusionWe found that the differences in gene expression between the two groups were related to immunity, which may affect the effectiveness of immunotherapy. We hope our results can provide a reference for further research and help in finding other targets to improve the efficacy of immunotherapy.  相似文献   
56.
目的观察程序性死亡受体1(PD-1)单克隆抗体(单抗)Pembrolizumab治疗晚期肺癌的疗效和毒副反应。方法28例晚期肺癌患者,均接受PD-1单抗Pembrolizumab治疗,评价其近期疗效和毒副反应发生情况。结果28例患者中,3例患者于治疗1个月内因原发肿瘤进展、病情加重而死亡。其余25例患者,完全缓解1例、部分缓解4例、疾病稳定14例、疾病进展6例,客观反应率20.0%(5/25),疾病控制率76.0%(19/25)。可评价疗效的25例患者中位无进展生存期(PFS)为5.1个月,95%CI=(2.9,7.4)。28例患者常见的不良反应为疲乏5例(17.9%)、发热4例(14.3%)、免疫相关性肺炎6例(21.4%),其次为甲状腺功能减退3例(10.7%)、皮疹2例(7.1%)、腹泻2例(7.1%)、甲状腺功能亢进1例(3.6%)、心脏毒性1例(3.6%)。结论PD-1单抗Pembrolizumab对晚期肺癌疗效可,毒副作用可耐受。  相似文献   
57.
Case 4     
Prostatic biopsies of two groups of 4 and 6 patients with benign prostatic hyperplasia (BPH) (average age 69.5 years) before hormonal treatment with cyproterone acetate (group A) or bromocryptine (2-bromo-α-ergocryptine) (group B), respectively (Figs. 1 and 2), were evaluated by stereologic methods. To assess the pituitary gonadal function of the patients, the following steroid determinations were performed 1 day before the biopsy: luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, 17β-estradiol, testosterone. The drugs were administered over a period of 8 weeks, then suprapubic prostatectomy was performed.  相似文献   
58.
We previously showed that dual‐task cost (DTC) on gait speed in people with Parkinson''s disease (PD) improved after 6 weeks of the Agility Boot Camp with Cognitive Challenge (ABC‐C) exercise program. Since deficits in dual‐task gait speed are associated with freezing of gait and gray matter atrophy, here we performed preplanned secondary analyses to answer two questions: (a) Do people with PD who are freezers present similar improvements compared to nonfreezers in DTC on gait speed with ABC‐C? (b) Can cortical thickness at baseline predict responsiveness to the ABC‐C? The DTC from 39 freezers and 43 nonfreezers who completed 6 weeks of ABC‐C were analyzed. A subset of 51 participants (21 freezers and 30 nonfreezers) with high quality imaging data were used to characterize relationships between baseline cortical thickness and delta (Δ) DTC on gait speed following ABC‐C. Freezers showed larger ΔDTC on gait speed than nonfreezers with ABC‐C program (p < .05). Cortical thickness in visual and fronto‐parietal areas predicted ΔDTC on gait speed in freezers, whereas sensorimotor‐lateral thickness predicted ΔDTC on gait speed in nonfreezers (p < .05). When matched for motor severity, visual cortical thickness was a common predictor of response to exercise in all individuals, presenting the largest effect size. In conclusion, freezers improved gait automaticity even more than nonfreezers from cognitively challenging exercise. DTC on gait speed improvement was associated with larger baseline cortical thickness from different brain areas, depending on freezing status, but visual cortex thickness showed the most robust relationship with exercise‐induced improvements in DTC.  相似文献   
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目的探讨控制超排卵(COH)中获卵数对体外受精一胚胎移植(IVF—ET)妊娠结局的影响,及为避免重度OHSS全胚冷冻的效果。方法接受常规IVF助孕治疗的不孕症患者358例(除外ICSI,Half—ICSI,Re—ICSI)。根据获卵数不同分为3组,其中获卵数1~10者122例(I组),获卵数11~20者183例(II组),获卵数〉20者53例(Ⅲ组);358例中发生OHSS48例全胚冷冻,其中I组无全胚冷冻,Ⅱ组全胚冷冻28例,Ⅲ组全胚冷冻20例。结果全胚冷冻组与新鲜移植组比较:年龄及优胚率无明显差异,着床率及临床妊娠率无明显差异;新鲜移植第Ⅲ组着床率及临床妊娠率低于全胚冷冻第Ⅲ组,差异有显著性。结论OHSS时全胚冷冻保证了妊娠结局,尤其对获卵数〉20的患者有利。  相似文献   
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