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931.
The use of skin virome offers a unique approach for human identification purposes in instances where a viable and statistically relevant human DNA profile is unavailable. The skin virome may act as an alternative DNA profile and/or an additional form of probative genetic material. To date, no study has attempted to investigate the human virome over a time series across various physical locations of the body to identify its diagnostic potential as a tool for human identification. For this study, we set out to evaluate the stability, diversity, and individualization of the human skin virome. An additional goal was to identify putative viral signatures that can be used in conjunction with traditional forensic STR loci. In order to accomplish this, human viral metagenomes were collected and sequenced from 42 individuals at three anatomical locations (left hand, right hand, and scalp) across multiple collection periods over a 6-month window of time. Assembly dependent and independent bioinformatic approaches, along with a database centered assessment of viral identification, resulted in three sets of stable putative viral markers. In total, with the three sets combined, we identified 59 viral biomarker regions, consisting of viral species and uncharacterized viral genome assemblies, that were stable over the sampling period. Additionally, we found the abundance profiles of these 59 viral biomarkers, based on presence or absence, to be significantly different across subjects (P < 0.001). Here we demonstrate that not only is the human virome applicable to be used for human identification, but we have identified many viral signatures that can putatively be used for forensic applications, thus providing a foundation to the novel field of forensic virology.  相似文献   
932.
Nutritional support is a fundamental component of the care of the extremely preterm infant, including the “micro preemie” (here defined as a baby born weighing less than 500 g), but goes beyond considerations of milk as a food. This is because milk from an infant's own mother, unlike currently available substitutes, additionally provides invaluable non-nutritive benefits.Nutritional support requires suitable devices or techniques to administer nutrients enterally or intravenously, products shown to be safe in preterm populations, and efficacy demonstrated in respect of important functional outcomes. Sadly, preterm feeding remains characterised by a deficit of evidence. In this chapter, we will briefly describe the history of preterm nutrition, discuss current enteral and parenteral practice, important evidence gaps, a summary of approaches for evaluating nutritional practice, and key considerations for future endeavour. Our discussion refers to all extremely preterm infants and it not confined to the micro preemie.  相似文献   
933.
婴儿期是肠道菌群形成和发展最为关键的时期,作为肠道菌群演替速度较快的重要阶段,稳定的肠道菌群定植对机体健康、免疫系统的建立及完善有着重大且长远的意义。母乳中富含人乳低聚糖(HMOs),能够有效促进婴儿肠道中有益细菌的生长,抑制病原菌的侵袭,改善肠道菌群组成,提高菌种多样性,促进婴儿生长发育。现就HMOs的研究现状及其对婴儿肠道菌群的影响进行综述。  相似文献   
934.
2022年全球多个非地方性流行国家发生了人感染猴痘(human monkeypox,HMPX)暴发疫情,世界卫生组织(World Health Organization,WHO)评述此次暴发是“非同寻常的(atypical)”。要理解这一评语,就必须对猴痘及HMPX的历史有充分的认识,首先知道什么是“寻常的”暴发。因此,该文系统回顾了猴痘,尤其是HMPX的流行病学史,并结合近期WHO等组织机构,以及专家学者的观点,讨论分析此次疫情非同寻常的表现及可能原因。在为读者呈现64年来发人深省的猴痘病毒与人类互动历史的同时,也提供了HMPX暴发疫情多方面的信息和观点,有助于理解WHO等对当前疫情危险性的评估,认识暴发疫情对未来临床和公共卫生的深远影响。  相似文献   
935.
Forensic age estimation is an invaluable aspect of human identification. Out of these many means of age estimation, few regions with untapped potential for assistance in forensic age estimation are the age-related changes in the laryngeal cartilages. As the age advances, the thyroid and cricoid cartilages undergo gradual calcification in an individual. These age-related changes can be visualized in both the living and the dead using conventional radiography and can be objectively assessed. The objective of the present study was to evaluate the age-related changes in the laryngeal cartilages and the results may be utilized for age estimation in forensic examinations. The laryngeal cartilages were carefully dissected using standard procedures from 75 cadavers of age ranging from 17 to 65 years, during the post-mortem examination. The laryngeal cartilages were radiographed and replaced in the body cavity before culminating the post-mortem examination. The calcification of both cartilages was studied by using the standard grading method. Calcification scores of individual regions of both the laryngeal cartilages show a statistically significant positive correlation with chronological age (P < 0.05). Regression models derived from the degree of calcification of thyroid and cricoid cartilages showed standard error of estimates that ranged between 9.90 and 11.07 years. Considering the standard error of estimates of the regression analysis, the present study concludes that these regression models can be used in adjunct with other methods of age estimation such as the skeletal and dental age or when such methods are not viable as in cases of charred or mutilated remains.  相似文献   
936.
Involuntary sterilization is a violation of human rights and grounds for asylum in the United States. Forensic medical evaluations can be useful in documenting this form of persecution and supporting asylees’ claims for immigration relief. We conducted a retrospective case analysis of the personal and medical affidavits of 14 asylum-seeking women from four Latin America countries who all reported they had been involuntarily sterilized. Sixty-four percent said that “consent” was coerced; the remainder were unaware of having been sterilized at the time of the procedure. In all cases, findings on hysterosalpingogram were consistent with sterilization, revealing that all 14 had undergone a tubal ligation. Eighty-six percent of the women had been sterilized at the time of childbirth. The healthcare providers involved in the 14 cases failed to obtain informed consent, misled patients about sterilization, engaged in discriminatory behavior, and/or breached patient confidentiality regarding their HIV-status. All 14 asylum cases were defensive; of the 7 cases (50%) that have been decided to date, 100% have been granted asylum.  相似文献   
937.
Behçets disease (BD) is a connective tissue disorder characterized by recurrent orogenital ulcer, uveitis, and skin lesions. Recurrent aphthous ulcer is associated with human cytomegalovirus (HCMV). To investigate the possible role of HCMV in BD, we measured the titers of IgG, IgM, and IgA anti-HCMV antibodies in 73 Korean patients with BD, 50 with scleroderma, 70 with systemic lupus erythematosus, and 50 from healthy controls by indirect immunofluorescent staining. The titer of IgG anti-HCMV antibody was significantly lower in patients with BD than in controls (geometric mean 3115.4 vs 9687.6, P=0.0001 by Wilcoxons rank sum test), as was the titer of IgA anti-HCMV antibody (geometric mean 1.9 vs 15.7, P=0.0001, Wilcoxons rank sum test). In conclusion, we found significantly lower antibody responses to HCMV in patients with BD.  相似文献   
938.
荧光素异硫氰酸酯标记高密度脂蛋白-2保持天然高密度脂蛋白-2的生物活性。人肝癌SMMC-7721细胞与荧光标记无载脂蛋白E-高密度脂蛋白-2在37℃培养3h左右,细胞结合与内吞的荧光强度分别为13.5±0.8和9.2±0.5(±s土)。细胞进一步在37℃培养2h细胞释放的三氯醋酸沉淀和三氯醋酸可溶性荧光强度分别为5.1±0.4和0.67±0.17.4℃培养2h,细胞释放三氯醋酸沉淀荧光强度为0.41±0.16。结果提示:①细胞内吞高密度脂蛋白-2没有经过溶酶体分解途径;②细胞释放高密度脂蛋白-2载脂蛋白是一种取决于温度的逆向胞饮机制。  相似文献   
939.
目的研究17β-雌二醇(E2)对人肠系膜动脉的舒张作用及其机制。方法采用离体血管环灌流的方法,观察E2对内皮完整和去内皮人肠系膜动脉的舒张作用,以及一氧化氮合酶(eNOS)选择性抑制剂N-硝基-L-精氨酸甲酯(L-NAME)、L-NAME+前列环素(PGs)抑制剂吲哚美辛(INDO)、格列本脲(GLY)对这一过程的影响。结果E2(0.5~20.0μmol/L)均可剂量依赖性地舒张人肠系膜动脉;该作用在低水平时内皮完整组明显大于无内皮组(P<0.01),且在内皮完整组E2的舒张作用可分别被L-NAME、L-NAME+INDO、GLY减弱(P均<0.01);高水平时去内皮组与内皮完整组E2的舒张比例差异无统计学意义(P>0.05),在内皮完整组各阻滞剂孵育20 min后E2的舒张作用不能被阻断(P均>0.05)。结论E2对人肠系膜动脉的舒张作用在低水平时具有内皮依赖性,与内皮NO和内皮源性超极化因子(EDHF)的释放、KATP的激活有关,且EDHF比NO更重要;而高水平时的E2舒张人肠系膜动脉是非内皮依赖的,为E2的临床应用提供了重要的实验依据。  相似文献   
940.
This is a study to define the profile of chemokine receptors expressed on isolated infiltrating lymphocytes in human abdominal aortic aneurysms (AAAs), and to examine their role in lymphoid recruitment. AAA T-lymphocytes were CXCR4-positive, CCR7-negative and partially CXCR3 and CCR5-positive. Functionally, AAA T-cells were proinflammatory effector cells, as they produced IFN-γ and granzyme A. AAA B-lymphocytes were CXCR4-positive and exhibited low CXCR5 expression. A relevant feature of infiltrating T- and B-lymphocytes was the high intensity of CXCR4 expression and the capability to migrate to CXCL12. CXCL12-producing cells were found in the adventitia of AAA. These cells were CD45-negative and partially VCAM-1 and DR-positive. In summary, the present results suggest that CXCR4, expressed on infiltrating lymphocytes, and CXCL12, expressed on stromal cells, is involved in the recruitment of lymphocytes within the arterial wall in AAA.  相似文献   
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