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41.
Whether germline (g) breast cancer susceptibility gene (BRCA) mutations are located within or outside the ovarian cancer cluster region (OCCR) (1380‐4062 bp for gBRCA1, and between 3249‐5681 bp and 6645‐7471 bp for gBRCA2) may influence risk variations for ovarian cancers. This ad hoc analysis of the CHARLOTTE epidemiological study in Japan assessed the distribution of gBRCA1/2 mutations in patients with newly diagnosed ovarian cancer, and investigated an association between gBRCA1/2 mutation locations and ovarian cancer risk. Differences in patient background and clinical characteristics in subgroups stratified by gBRCA1/2 mutation locations were also evaluated. We analyzed the data of 93 patients (14.7%) from the CHARLOTTE study who were positive for gBRCA1/2 mutations. After excluding 16 cases with L63X founder mutation, 28 (65.1%) of gBRCA1 mutations were within the OCCR. Of 30 gBRCA2 mutations, 15 (50.0%) were within the OCCR. Of 27 patients (one patient excluded for unknown family history) with gBRCA1 mutations located in the OCCR, 11 (40.7%) had a family history of ovarian cancer; the proportion of patients with a family history of ovarian cancer and gBRCA1 mutations outside the OCCR was lower (13.3%). Sixty percent of patients with gBRCA1 mutations outside the OCCR had a family history of breast cancer; the proportion of patients with a family history of breast cancer and gBRCA1 mutations within the OCCR was relatively lower (33.3%). Understanding the mutation locations may contribute to more accurate risk assessments of susceptible individuals and early detection of ovarian cancer among gBRCA mutation carriers.  相似文献   
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Epidermolysis bullosa (EB) is a heritable blistering disorder. We performed a next-generation sequencing-based multigene panel test and successfully predicted 100% of the EB types, including, 36 EB simplex (EBS), 13 junctional EB (JEB), 86 dystrophic EB (DEB), and 3 Kindler EB. Chinese JEB and recessive DEB (RDEB) patients have relatively mild phenotypes; for severe type separately accounts for 45.5% and 23.8%, respectively. We identified 96 novel and 49 recurrent pathogenic variants in 11 genes, although we failed to detect the second mutation in one JEB and five RDEB patients. We identified one novel p.E475K mosaic mutation in the clinically normal mother of one out of 13 EBS patients with KRT5 mutations, one recurrent p.G2034R mosaic mutation, and one novel p.G2043R mosaic mutation in the clinically normal relatives of two out of 19 dominant DEB patients. This study shows that next-generation technology could be an effective tool in diagnosing EB.  相似文献   
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ABSTRACT

Although exclusive breastfeeding has been linked to lower rates of postnatal HIV transmission compared to nonexclusive breastfeeding, mechanisms underlying this are unclear. Across a longitudinally sampled cohort of South African infants, we showed that exclusively breastfed (EBF) infants had altered gut bacterial communities when compared to nonexclusively breastfed (NEBF) infants, as well as reduced peripheral CD4 + T cell activation and lowered chemokine and chemokine receptor expression in the oral mucosa. We further demonstrated that the relative abundance of key taxa was correlated with peripheral CD4 + T cell activation. Here, we supplement those findings by using compositional data analyses to identify shifts in the abundance of several Bifidobacteria strains relative to select strains of Escherichia, Bacteroides, and others that are associated with the transition to NEBF. We illustrate that the abundance ratio of these taxa is tightly correlated with feeding modality and is a strong predictor of peripheral T cell activation. More broadly, we discuss our study in the context of novel developments and explore future directions for the field.  相似文献   
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目的探究目标教学运用在神经内科临床护理带教中的效果及方法。方法选取2018年6月-2019年6月期间到该院神经内科实习的48名女护生作为研究对象,采取随机双盲方法,将其均分为两组,各24例,对照组护生行常规护理带教模式,观察组护生行目标教学护理带教,对比两组护生出科综合成绩和带教满意度。结果观察组出科综合成绩显著高于对照组(t=3.732、6.862、6.715,P<0.05),且带教满意度优于对照组(χ~2=5.400,P<0.05)。结论在神经内科临床护理带教工作中运用目标教学法可调动护生学习积极性,提升护士对护理知识的掌握程度,提高带教满意度。  相似文献   
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Unresectable neuroendocrine neoplasms (NENs) often poorly respond to standard therapeutic approaches. Alkylating agents, in particular temozolomide, commonly used to treat high-grade brain tumors including glioblastomas, have recently been tested in advanced or metastatic NENs, where they showed promising response rates. In glioblastomas, prediction of response to temozolomide is based on the assessment of the methylation status of the MGMT gene, as its product, O6 -methylguanine-DNA methyltransferase, may counteract the damaging effects of the alkylating agent. However, in NENs, such a biomarker has not been validated yet. Thus, we have investigated MGMT methylation in 42 NENs of different grades and from various sites of origin by two different approaches: in contrast to methylation-specific PCR (MSP), which is commonly used in glioblastoma management, amplicon bisulfite sequencing (ABS) is based on high-resolution, next-generation sequencing and interrogates several additional CpG sites compared to those covered by MSP. Overall, we found MGMT methylation in 74% (31/42) of the NENs investigated. A higher methylation degree was observed in welldifferentiated tumors and in tumors originating in the gastrointestinal tract. Comparing MSP and ABS results, we demonstrate that the region analyzed by the MSP test is sufficiently informative of the MGMT methylation status in NENs, suggesting that this predictive parameter could routinely be interrogated also in NENs.  相似文献   
49.
《Clinical lung cancer》2020,21(5):443-449.e4
BackgroundTraditionally, elective nodal irradiation (ENI) has been used in clinical trials that have established thoracic radiotherapy as instrumental in improving survival for patients with limited-stage small-cell lung cancer (LS-SCLC). However, several reports have suggested that the omission of ENI might be appropriate. Current US practice patterns are unknown regarding ENI for patients with LS-SCLC.Materials and MethodsWe surveyed US radiation oncologists via an institutional review board-approved questionnaire. The questions covered demographics, treatment recommendations, and self-assessed knowledge of key clinical trials. χ2 and Cochran-Armitage tests were used to evaluate for statistically significant correlations between responses.ResultsWe received 309 responses. Of the respondents, 21% recommended ENI for N0 LS-SCLC, 29% for N1, and 30% for N2; 64% did not recommend ENI for any of these clinical scenarios. The respondents who recommended ENI were more likely to have been practicing for > 10 years (P < .001), more likely to be in private practice (P = .04), and less likely to be familiar with the ongoing Cancer and Leukemia Group B 30610 trial (P = .04). Almost all respondents (93%) prescribed the same radiation dose to the primary disease and involved lymph nodes. When delivering ENI, 36% prescribed the same dose to the involved and elective nodes, and 64% prescribed a lower dose to the elective nodes.ConclusionNearly two thirds of respondents did not recommend ENI, which represents a shift in practice. A recent large clinical trial that omitted ENI reported greater overall survival than previously reported and lower-than-expected radiation toxicities, lending further evidence that omitting ENI should be considered a standard treatment strategy.  相似文献   
50.
吴洋  宋燕妮 《现代肿瘤医学》2020,(18):3255-3259
乳腺癌是一类具有异质性的肿瘤,不同患者的治疗方法和疗效都不相同。尽管目前仍在努力为激素受体(hormone receptor,HR)阳性(+)、人表皮生长因子受体2(human epidermal growth factor receptor 2,HER-2)阴性(-)、淋巴结(axillary lymph node,ALN)阴性(-)的早期乳腺癌患者寻找合适的治疗方法,但其术后是否需要化疗仍然是肿瘤科医生面临的一个难题。以往治疗主要依赖于经典的组织病理学和免疫组织化学技术,随着精准医疗时代的到来,我们需要更定量的诊断方法和合理的个体化治疗。虽然化疗可降低疾病复发风险并提高生存率,但它带来的不良反应事件会降低患者的生活质量,尤其低复发风险(recurrence risk,RS)有可能超过化疗益处。21基因检测不仅可以预测这类早期乳腺癌化疗疗效及评估预后,还可提供精准的个体化治疗方案指导用药,为患者增添信心。本文就乳腺癌21基因检测的研究进展进行综述。  相似文献   
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