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Omicron(B.1.1.529)变异株于2021年11月24日首次从南非报告给世界卫生组织,截至2021年12月8日全球共有57个国家和地区报告了Omicron感染病例。目前Omicron变异株在部分非洲国家已成为主导毒株,且传播速度快。尽管Omicron变异株引起的疾病症状较轻,多数病例为无症状感染者和轻型患者,但病例数量的快速增长可能给全球卫生系统带来沉重压力。此外,Omicron变异株的变异来源、传播特征、疫苗抗性等尚不明确,给各国和地区的疫情防控带来很大挑战。本文就Omicron变异株的病原学特征、变异来源、传播特征及可能的机制、流行现状、疫苗对其保护效果、防控措施等方面的研究进展进行综述,以期为科学防控Omicron变异株所致疫情提供参考。 相似文献
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Héctor Díaz-Zabala Xingyi Guo Jie Ping Wanqing Wen Xiao-Ou Shu Jirong Long Loren Lipworth Bingshan Li Mary Kay Fadden Tuya Pal William J. Blot Qiuyin Cai Christopher A. Haiman Julie R. Palmer Maureen Sanderson Wei Zheng 《Genetics in medicine》2022,24(7):1468-1475
PurposeStudies conducted primarily among European ancestry women reported 12 breast cancer predisposition genes. However, etiologic roles of these genes in breast cancer among African ancestry women have been less well-investigated.MethodsWe conducted a case-control study in African American women, which included 1117 breast cancer cases and 2169 cancer-free controls, and a pooled analysis, which included 7096 cases and 8040 controls of African descent. Odds ratios of associations with breast cancer risk were estimated.ResultsUsing sequence data, we identified 61 pathogenic variants in 12 breast cancer predisposition genes, including 11 pathogenic variants not yet reported in previous studies. Pooled analysis showed statistically significant associations of breast cancer risk with pathogenic variants in BRCA1, BRCA2, PALB2, ATM, CHEK2, TP53, NF1, RAD51C, and RAD51D (all P < .05). The associations with BRCA1, PALB2, and RAD51D were stronger for estrogen receptor (ER)-negative than for ER-positive breast cancer (P heterogeneity < .05), whereas the association with CHEK2 was stronger for ER-positive than for ER-negative breast cancer.ConclusionOur study confirmed previously identified associations of breast cancer risk with BRCA1, BRCA2, PALB2, ATM, TP53, NF1, and CHEK2 and provided new evidence to extend the associations of breast cancer risk with RAD51C and RAD51D, which was identified previously in European ancestry populations, to African ancestry women. 相似文献
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Clinical characteristics of pediatric patients with COVID-19 between Omicron era vs. pre-Omicron era
《Journal of infection and chemotherapy》2022,28(11):1501-1505
IntroductionDetailed data on clinical characteristics in children with the omicron strain of SARS-COV-2 are limited.MethodsWe conducted a retrospective observational study of children with COVID-19 at the National Center for Child Health and Development to evaluate the clinical manifestations during and before the emergence of the omicron variant. Only symptomatic patients without underlying diseases were included. Participants were divided into two temporal groups: the “omicron era” (1/2022–2/2022) and the “pre-omicron era,” where the delta variant predominated (7/2021–11/2021). The patients were subclassified into an older vaccine-eligible group (aged 12–17 years), a younger vaccine-eligible group (aged 5–11 years), and a vaccine-ineligible group (aged 0–4 years).ResultsWe compared 113 patients in the omicron era with 106 in the pre-omicron era. Most patients in both eras had non-severe disease, and no patients required mechanical ventilation or died. Among patients aged 0–4 years, sore throat and hoarseness were more common during the omicron era than the pre-omicron era (11.1% vs. 0.0% and 11.1% vs. 1.5%, respectively). Croup syndrome was diagnosed in all patients with hoarseness. Among patients aged 5–11 years, vomiting was more frequent during the omicron era (47.2%) than during the pre-omicron era (21.7%). Cough and rhinorrhea were less common during the omicron era in patients aged 0–4 and 5–11 years, respectively, than during the pre-omicron era.ConclusionsIn children with COVID-19, clinical manifestations differed between the omicron and pre-omicron eras. In the Omicron era, croup syndrome was more frequent in vaccine-ineligible children. 相似文献
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Lesch-Nyhan综合征是一种罕见的X连锁隐性遗传病,在自伤行为出现前,易被误诊为脑瘫,延误诊治。先证者,男,8岁7个月,因发育落后8年余,肌张力异常就诊。多次血生化均提示尿酸增高,遗传学分析结果证实患儿为HPRT1基因c.200_201delTG变异,经ACMG评级为疑似致病性变异,Sanger测序验证发现该变异遗传自患儿母亲,为未报道的新变异,从而确诊为HPRT1基因相关Lesch-Nyhan综合征,口服别嘌醇片、碳酸氢钠片6月后尿酸水平较前明显下降,仍无自伤行为。临床上遇到不明原因脑瘫表现者,应及早行遗传学检查,以帮助早期诊断和遗传咨询。 相似文献
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《European journal of medical genetics》2021,64(12):104345
BackgroundEpidermolysis bullosa (EB) is a genodermatosis characterized by skin fragility and blisters with variable severity. Patients with Dystrophic EB (DEB) or Junctional EB (JEB) mainly present to clinic due to greater functional impairment. Pathogenic sequence variations in COL7A1 are implicated in DEB.ObjectiveWe have tried to decipher the molecular spectrum and genotype phenotype correlation of 21 Indian patients with EB.MethodsNext generation sequencing (NGS) was performed to determine the pathogenic variants. Sanger sequencing was also done for validation of the variants in eleven individuals.ResultsPathogenic variants were detected in 20 individuals (diagnostic yield of 95%). Majority of them (90%) had sequence variation in COL7A1 while two had pathogenic variants in ITGB4 and KRT14 respectively. Out of the 18 patients confirmed to have DEB, 3 had Dominant DEB (DDEB) whereas 15 patients had Recessive DEB (RDEB). Amongst 23 sequence variations identified, 12 were found to be novel (3 were missense, 5 were premature termination codon variants while 4 were splice-site changes).ConclusionGenotype phenotype correlation was noted with milder manifestations in those with dominant inheritance types. Exact molecular diagnosis can be ascertained by NGS in majority of cases. 相似文献
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Qiaojun Zeng Tiantian Tang Biru Huang Shiyi Bu Yingqi Xiao Yumeng Dai Zixin Wei Linjie Huang Shanping Jiang 《The Journal of international medical research》2021,49(4)
ObjectiveSingle nucleotide polymorphisms (SNPs) of pentraxin 3 (PTX3) are associated with various outcomes of lung infections. This study aimed to analyze the relationship between PTX3 polymorphisms and the severity of community-acquired pneumonia (CAP).MethodsThis is a retrospective case-control study comprising 43 patients with severe CAP (SCAP) and 97 patients with non-severe CAP. Three SNPs in the PTX3 gene (rs2305619, rs3816527, and rs1840680) from peripheral blood samples were genotyped by real-time polymerase chain reaction. The association between each SNP and the CAP severity was analyzed by logistic regression analysis.ResultsWe found that the rs1840680 polymorphism was significantly associated with CAP clinical severity. However, no such association was observed for the genotypes and allele frequencies of rs2305619 or rs3816527. The PTX3 rs1840680 AG genotype was an independent factor for a lower risk of SCAP after multivariate logistic regression analysis. Male sex and coronary heart disease were associated with an increased risk of SCAP.ConclusionsThe PTX3 rs1840680 AG genotype was found to be associated with a lower risk of SCAP, and may serve as a potential protective biomarker to help clinical judgment and management. 相似文献