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991.
《Reproductive biology》2021,21(4):100569
The successful implantation of the embryo into a receptive endometrium is essential for the establishment of a viable pregnancy while recurrent implantation failure (RIF) is a real challenge in assisted reproduction. The maternal innate immune system, specifically the Toll-like receptors (TLRs), are involved in maintaining immunity in the female reproductive tract (FRT) required for fertility. In this study, we aimed to investigate the importance of innate immunity-related gene expression in the regulation of human fertility and as a prediction of potential outcome of in vitro fertilization - embryo transfer (IVF-ET), thus, we assessed the gene expression levels of TLR signalling molecules using quantitative real-time PCR between endometrial biopsies of healthy fertile women, and the patients experiencing RIF. Interestingly, our results showed that, TRIB2 and TLR9 genes were differentially expressed between the endometrial biopsies of healthy women and those with RIF. However, comparing expression levels of same genes between pre-receptive and receptive healthy endometrial biopsies showed different genes (ICAM1, NFKBIA, VCAM1, LIF, VEGFB, TLR5) had significantly altered expression, suggesting their involvement in endometrial receptivity. Thus, further investigations will enable us to better understand the role of these genes in the biology of FRT and as a possible target for the improvement of infertility treatments and/or development of non-hormonal contraception. 相似文献
992.
Mengyao Guo Guoqing Wang Tingting Lv Xiaojing Song Tiancheng Wang Guanghong Xie Yongguo Cao Naisheng Zhang Rongfeng Cao 《Theriogenology》2014
Mycoplasma bovis infection can cause endometrial inflammation leading to infertility and involuntary culling in dairy cows. Because extracellular matrix (ECM) proteins affect the adherence of mycoplasma to eukaryotic cell surface, they may play a role in the pathogenesis of the bacteria. The objective of the present study was to evaluate the endometrial inflammatory response and ECM protein expression induced by M bovis. Endometrial concentrations of inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and mRNA and protein expression of collagen IV (CL-IV), fibronectin (FN), and laminin (LN) were evaluated 10, 20, and 30 days after M bovis intrauterine infusion in breed cows 18 days postpartum. The presence of the bacteria in the uterus was detected by nested polymerase chain reaction and denaturing gradient gel electrophoresis. Endometrial TNF-α, IL-1β, and IL-6 concentrations in the treatment group were greater (P < 0.05) than in the positive and negative control groups 20 and 30 days after infusion. Endometrial CL-IV, FN, and LN mRNA and protein expression increased (P < 0.01) 20 days after infusion in all groups. However, the increase was more pronounced in the treatment group and reactive expressions were greater (P < 0.05) than in the positive and negative control groups 10, 20, and 30 days after infusion. In conclusion, M bovis triggered endometrial inflammatory response and increased CL-IV, FN, and LN mRNA and protein expression. The abnormal expression of ECM these proteins may promote the pathogenic effects of M bovis that lead to endometrial tissue damage and infertility. 相似文献
993.
Postmortem Miscoding Lesions in Sequence Analysis of Human Ancient Mitochondrial DNA 总被引:1,自引:0,他引:1
Genetic miscoding lesions can cause inaccuracies during the interpretation of ancient DNA sequence data. In this study, genetic
miscoding lesions were identified and assessed by cloning and direct sequencing of degraded, amplified mitochondrial DNA (mtDNA)
extracted from human remains. Forty-two individuals, comprising nine collections from five geographic locations, were analyzed
for the presence of DNA damage that can affect the generation of a correct mtDNA profile. In agreement with previous studies,
high levels (56.5% of all damage sites) of proposed hydrolytic damage products were observed. Among these, type 2 transitions
(cytosine → thymine or guanine → adenine), which are highly indicative of hydrolytic deamination, were observed in 50% of
all misincorporations that occurred. In addition to hydrolytic damage products, oxidative damage products were also observed
in this study and were responsible for approximately 43.5% of all misincorporations. This level of misincorporation is in
contrast to previous studies characterizing miscoding lesions from the analysis of bone and teeth, where few to no oxidative
damage products were observed. Of all the oxidative damage products found in this study, type 2 transversions (cytosine → adenine/guanine → thymine
or cytosine → guanine/guanine → cytosine), which are commonly formed through the generation of 8-hydroxyguanine, accounted
for 30.3% of all genetic miscoding lesions observed. This study identifies the previously unreported presence of oxidative
DNA damage and proposes that damage to degraded DNA templates is highly specific in type, correlating with the geographic
location and the taphonomic conditions of the depositional environment from which the remains are recovered.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
Objective: To perform an oral biopsy survey focused on the incidence of oral lesions in Brazilian elderly patients. Methods: A total of 17 329 oral biopsy records were analysed and divided into two age groups: elderly patients, ≥60 years old; and non‐elderly patients, <60 years old. Information about sex, race, age and histopathological diagnosis (categorised in non‐neoplastic and neoplastic lesions) was collected. Differences of diagnosis incidence were tested by comparison between two proportions (binomial test). Results: The incidence of epithelial malignant neoplasms and pre‐malignant lesions in the elderly group was higher than non‐elderly group, as well as autoimmune diseases and salivary gland tumours. The three most prevalent lesions in the elderly group were inflammatory fibrous hyperplasia, squamous cell carcinoma, and fibroma. Conclusion: The distribution of oral diseases using biopsies allows greater accuracy in data about oral health of elderly patients, especially when considering malignant and pre‐malignant lesions. 相似文献
995.
恶性卵巢肿瘤严重威胁着妇女健康和生命,其重要原因之一是易发生淋巴转移,给临床诊断和治疗带来困难。近年来国内外对恶性卵巢肿瘤淋巴转移的机制及其与相关基因表达进行了一系列的研究,现就这方面的进展作一综述。 相似文献
996.
Amerigo Beneduci 《Cell biochemistry and biophysics》2009,55(1):25-32
The potential antiproliferative effects of low power millimeter waves (MMWs) at 42.20 and 53.57 GHz on RPMI 7932 human skin
melanoma cells were evaluated in vitro in order to ascertain if these two frequencies, comprised in the range of frequency
used in millimeter wave therapy, would have a similar effect when applied in vivo to malignant melanoma tumours. Cells were
exposed for 1 h exposure/day and to repeated exposure up to a total of four treatments. Plane wave incident power densities
<1 mW/cm2 were used in the MMWs-exposure experiments so that the radiations did not cause significant thermal effects. Numerical simulations
of Petri dish reflectivity were made using the equations for the reflection coefficient of a multilayered system. Such analysis
showed that the power densities transmitted into the aqueous samples were ≤0.3 mW/cm2. Two very important and general biological endpoints were evaluated in order to study the response of melanoma cells to these
radiations, i.e. cell proliferation and cell cycle. Herein, we show that neither cell doubling time nor the cell cycle of
RPMI 7932 cells was affected by the frequency of the GHz radiation and duration of the exposure, in the conditions above reported. 相似文献
997.
目的:探讨子宫内膜癌患者血浆溶血磷脂酸(LPA)、血清癌抗原125(CA125)及人附睾蛋白4(HE4)的表达及与临床病理特征的关系。方法:选取2014年3月到2016年6月在同济大学附属第一妇婴保健院进行治疗的子宫内膜癌患者76例作为观察组,另选取我院同期收治的子宫内膜增生症患者50例作为良性病变组,再选取同期在我院体检结果为健康的志愿者50例作为对照组。比较三组受试者血浆LPA、血清CA125以及HE4水平。以病理检测结果为金标准,计算血浆LPA、血清CA125、HE4诊断子宫内膜癌的灵敏度、特异度、阳性预测值、阴性预测值。分析子宫内膜癌患者血浆LPA、血清CA125以及HE4水平与临床病理特征的关系。结果:观察组的血浆LPA、血清CA125以及HE4水平均高于对照组和良性病变组(P0.05),良性病变组的血浆中CA125水平高于对照组(P0.05)。血浆LPA、血清CA125以及HE4诊断子宫内膜癌的灵敏度、特异度、阳性预测值、阴性预测值比较无统计学差异(P0.05)。子宫内膜癌患者LPA水平与年龄、肿瘤直径无关(P0.05),与淋巴结转移、临床分期、分化程度、疾病类型有关(P0.05);CA125、HE4水平与年龄、疾病类型无关(P0.05),与淋巴结转移、临床分期、肿瘤直径、分化程度有关(P0.05)。结论:子宫内膜癌患者血浆LPA、血清CA125以及HE4水平偏高,LPA、CA125、HE4与部分临床病理参数相关,三指标对子宫内膜癌均有较高的诊断价值。 相似文献
998.
环氧合酶-2在子宫内膜癌中上调表达的临床意义 总被引:2,自引:0,他引:2
目的 探讨环氧合酶 2与子宫内膜癌发生、发展中的关系。方法 研究对象分为 5组 ,增生期组 2 5例 ,分泌期组 2 5例 ,内膜炎组 2 5例 ,非典型性增生组 2 3例 ,子宫内膜癌组 34例 ,应用免疫组化和定量RT PCR方法 ,检测其中Cox 2蛋白和mRNA水平表达。结果 6 7%的子宫内膜癌表达Cox 2 ,在转录和蛋白水平子宫内膜癌组的Cox 2表达强度明显高于其它四组 (免疫组化评分分别为 :增生期组 5 4 6± 0 12 3,分泌期组 3 2 0± 0 176 ,内膜炎组 4 78± 0 12 ,非典型性增生组 6 10±0 2 5 ,子宫内膜癌组 8 70± 0 93,相应mRNA含量依次为 92 8± 8 2 2fpg/ μg ,6 4 9± 11 0 8fpg/ μg ,79 4± 5 83fpg/ μg ,2 99 3± 10 6 8fpg/ μg ,4 93 0± 2 9 5 8fpg/ μg) ,差异有显著性 (P <0 0 5 ) ,内膜癌中 ,高分化细胞Cox 2表达高于低分化细胞 ,差异有显著性 (P <0 0 5 )。非典型性增生组Cox 2表达显著高于正常内膜和内膜炎组 ,增殖期组Cox 2表达高于分泌期组 ,差异有显著性 (P <0 0 5 )。结论 Cox 2可能在子宫内膜癌发生发展中起重要作用 ,可为子宫内膜癌的化学预防和化疗的辅助治疗提供新靶点 相似文献
999.
Epidermal growth factor receptor-dependent mechanisms have been implicated in growth signal transduction pathways that contribute to cancer development, including dermal carcinogenesis. Detection of the extracellular domain of the epidermal growth factor receptor (EGFR ECD) in serum has been suggested as a potential biomarker for monitoring this effect in vivo. Arsenic is a known human carcinogen, producing skin and other malignancies in populations exposed through their drinking water. One such exposed population, which we have been studying for a number of years, is in Bangladesh. The purpose of this study was to examine the EGFR ECD as a potential biomarker of arsenic exposure and/or effect in this population. Levels of the EGFR ECD were determined by enzyme-linked immunosorbent assay in the serum samples from 574 individuals with a range of arsenic exposures from drinking water in the Araihazar area of Bangladesh. In multiple regression analysis, serum EGFR ECD was found to be positively associated with three different measures of arsenic exposure (well water arsenic, urinary arsenic and a cumulative arsenic index) at statistically significant levels (p≤0.034), and this association was strongest among the individuals with arsenic-induced skin lesions (p ≤ 0.002). When the study subjects were stratified in tertiles of serum EGFR ECD levels, the risk of skin lesions increased progressively for each increase in all three arsenic measures (also stratified in tertiles) and this increasing risk became more pronounced among subjects within the highest tertile of EGFR ECD levels. These results suggest that serum EGFR ECD levels may be a potential biomarker of effect of arsenic exposure and may indicate those exposed individuals at greatest risk for the development of arsenic-induced skin lesions. 相似文献
1000.
李子卓杨秀华 《现代生物医学进展》2012,12(1):97-100
目的:研究脉压差等危险因素在中老年脑白质病变(WMLs)中的作用及临床意义。方法:入选213例无神经病学症状及体征的中老年病人(年龄>50岁),根据MRI影像学诊断标准分为中重度WMLs组(125例)及轻无WMLs组(88例),通过回顾性分析,记录年龄、性别、高血压史、糖尿病史、吸烟史、脉压差、收缩压、舒张压、血脂水平、左房内径,比较两组间各项指标差异,并做Binary Logistic回归分析,筛选出WMLs的独立危险因素。结果:在控制了高血压、年龄及其他混杂因素后,脉压差仍与WMLs密切相关,且独立于年龄和高血压,是WMLs的独立危险因素,OR值为2.954,95%CI 1.032~8.453。结论:压差在预测中老年人亚临床脑血管事件中可能起到重要作用。 相似文献