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1.
目的 探讨慢性乙型肝炎(CHB)患者肝X受体α(LXRα)和细胞色素P450亚型7A1(CYP7A1)基因表达水平与肝组织病理学炎症和纤维化程度的关系。方法 2019年1月~2020年10月我院收治的CHB患者118例,均接受肝穿刺活检,将炎症活动度分级>G2和肝纤维化分期>S2定义为肝组织炎症或纤维化程度显著;采用免疫组织化学染色法检测肝组织LXRα和CYP7A1表达,采用RT-PCR法检测LXRα mRNA和CYP7A1 mRNA水平。结果 118例CHB患者肝组织LXRα和CYP7A1蛋白和/或其mRNA阳性分别为78.0%和73.7%;38例肝组织显著炎症组LXRα mRNA和其蛋白(AOD)水平分别为(0.6±0.2)和(0.3±0.1),显著高于80例非显著炎症患者[分别为(0.4±0.1)和(0.1±0.0),P<0.05],CYP7A1 mRNA和其蛋白(AOD)水平分别为(0.8±0.2)和(0.4±0.1),显著高于非显著炎症患者[分别为(0.3±0.1)和(0.1±0.0),P<0.05];48例显著肝纤维化组肝组织LXRα mRNA和其蛋白(AOD)水平分别为(0.7±0.2)和(0.3±0.1),显著高于70例非显著肝纤维化患者[分别为(0.3±0.1)和(0.1±0.1),P<0.05],CYP7A1 mRNA和其蛋白(AOD)水平分别为(0.7±0.2)和(0.3±0.1),显著高于非显著肝纤维化患者[分别为(0.4±0.2)和(0.2±0.1),P<0.05]。结论 LXRα和CYP7A1表达上调可能参与了CHB患者肝组织炎症和肝纤维化发生发展过程,其机制值得进一步研究。  相似文献   
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目的:研究鱼藤素(De)诱导SGC-7901胃癌细胞凋亡的其作用机制。方法:运用CCK-8细胞活力检测法考察不同浓度(10、20、40、60、80、100 mol/L)鱼藤素作用24、48 h对SGC-7901胃癌细胞的细胞毒性;将SGC-7901胃癌细胞分为对照组及20、40 mol/L鱼藤素药物组,给药作用24 h后,蛋白质印迹法检测p-AKTThr308、叉头框蛋白O1(FoxO1)、B淋巴细胞瘤-2基因(Bcl-2)等蛋白的表达水平;运用蛋白激酶B(AKT)基因转染使SGC-7901胃癌细胞中AKT过表达,然后给予20、40 mol/L鱼藤素给药作用24 h,以未用AKT基因转染的SGC-7901胃癌细胞作为对照组蛋白质印迹法检测p-AKTThr308、FoxO1、Bcl-2等蛋白的表达水平,实时荧光定量PCR(RT-qPCR)检测FoxO1、Bcl-2、Bax mRNA的表达水平。结果:不同浓度的鱼藤素对SGC-7901胃癌细胞均具有一定的细胞毒性;20、40 mol/L鱼藤素给药作用24 h能够显著降低SGC-7901胃癌细胞中p-AKTThr308、Bcl-2等蛋白的表达水平,升高FoxO1的表达水平;与对照组比较,AKT基因转染后,SGC-7901胃癌细胞中p-AKTThr308、Bcl-2等蛋白表达水平升高,FoxO1蛋白表达降低,与模型组比较,20、40 mol/L鱼藤素给药作用后能够降低p-AKTThr308、Bcl-2等蛋白的表达水平,降低Bcl-2 mRNA的表达水平,升高FoxO1及Bax的表达水平。结论:鱼藤素能够通过作用于AKT/FoxO1信号通路诱导胃癌细胞SGC-7901凋亡。  相似文献   
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The intestinal mucosa is a highly compartmentalized structure that forms a direct barrier between the host intestine and the environment, and its dysfunction could result in a serious disease. As T cells, which are important components of the mucosal immune system, interact with gut microbiota and maintain intestinal homeostasis, they may be involved in the process of intestinal barrier dysfunction. P2X7 receptor (P2X7R), a member of the P2X receptors family, mediates the effects of extracellular adenosine triphosphate and is expressed by most innate or adaptive immune cells, including T cells. Current evidence has demonstrated that P2X7R is involved in inflammation and mediates the survival and differentiation of T lymphocytes, indicating its potential role in the regulation of T cell function. In this review, we summarize the available research about the regulatory role and mechanism of P2X7R on the intestinal mucosa-derived T cells in the setting of intestinal barrier dysfunction.  相似文献   
5.
ObjectiveWe present perinatal cytogenetic discrepancy in a pregnancy with mosaic 45,X/46, XY at amniocentesis and a favorable outcome.Case reportA 38-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,X[2]/46,XY[6]. Level II ultrasound at 20 weeks of gestation was unremarkable, and the fetus had normal male external genitalia. Following genetic counseling, the woman decided to continue the pregnancy. At 39 weeks of gestation, a healthy male baby was delivered with a body weight of 3410 g and a body length of 54.5 cm. The male external genital organs were normal. The cord blood had a karyotype of 46, XY (40/40 cells). The umbilical cord had a karyotype of 45,X[1]/46,XY[39]. During follow-up at age one month, his body weight was 4.4 Kg (15th-50th centile), and his body length was 56 cm (50th-85th centile). The infant was doing well. Interphase fluorescence in situ hybridization analysis on 100 buccal mucosal cells revealed no abnormal Y-deletion cell, and all cells contained one Y signal.ConclusionPerinatal cytogenetic discrepancy may occur in the pregnancy with mosaic 45,X/46, XY at amniocentesis.  相似文献   
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ObjectiveWe present progressive increase of the mosaic level for 45,X in 45,X/46, XX at different amniocenteses and postnatal progressive decrease of the 45,X cell line in a mosaic 45,X/46, XX fetus with a favorable outcome.Case reportA 35-year-old, primigravid woman underwent amniocentesis at 16 weeks of gestation because of the advanced maternal age. Amniocentesis revealed a karyotype of 45,X [6]/46,XX [14]. Among 20 colonies of cultured amniocytes, six colonies had a karyotype of 45,X, whereas the other 14 colonies had a karyotype of 46,XX. Simultaneous array comparative genomic hybridization (aCGH) on uncultured amniocytes revealed the result of arr [GRCh37] (X) × 1 [0.42] (1–22) × 2. Prenatal ultrasound findings were unremarkable. Repeat amniocentesis at 33 weeks of gestation revealed a karyotype of 45,X [13]/46,XX [7]. Among 20 colonies of cultured amniocytes, 13 colonies had a karyotype of 45,X, whereas the other seven colonies had a karyotype of 46,XX. Simultaneous interphase fluorescence in situ hybridization (FISH) analysis on 100 uncultured amniocytes revealed that 44 cells had monosomy X consistent with 44% mosaicism for 45,X, whereas the rest cells had disomy X. At 38 weeks of gestation, a 2675-g phenotypically normal female baby was delivered. The karyotypes of cord blood, umbilical cord and placenta were 45,X [12]/46,XX [28], 45,X [12]/46,XX [28] and 46,XX [40/40], respectively. When follow-up at age three months, the neonate was normal in development. The karyotypes of peripheral blood was 45,X [4]/46,XX [36], and interphase FISH analysis on 100 buccal mucosal cells showed monosomy X in 11 cells consistent with 11% mosaicism for 45,X, whereas the rest cells had disomy X.ConclusionProgressive increase of the mosaic level for 45,X in 45,X/46, XX at different amniocenteses can be associated with a favorable outcome and postnatal progressive decrease of the 45,X cell line.  相似文献   
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INTRODUCTIONFragile X syndrome (FXS) is the most prevalent X-linked intellectual disability (ID) and a leading genetic cause of autism, characterised by cognitive and behavioural impairments. The hyperexpansion of a CGG repeat in the fragile X mental retardation 1 (FMR1) gene leads to abnormal hypermethylation, resulting in the lack or absence of its protein. Tools for establishing the diagnosis of FXS have been extensively developed, including assays based on triplet-primed polymerase chain reaction (TP-PCR) for detection and quantification of the CGG trinucleotide repeat expansion, as well as determination of the methylation status of the alleles. This study aimed to utilise a simple, quick and affordable method for high sensitivity and specificity screening and diagnosis of FXS in institutionalised individuals with ID.METHODSA total of 109 institutionalised individuals at the Center for Social Rehabilitation of Intellectual Disability Kartini, Temanggung, Central Java, Indonesia, were screened in a three-step process using FastFrax™ Identification, Sizing and Methylation Status Kits.RESULTSTwo samples that were classified as indeterminate with respect to the 41-repeat control at the identification step were subsequently determined to be non-expanded by both sizing and methylation status analyses. Two samples classified as expanded at the identification step were determined to carry full mutation expansions > 200 repeats that were fully methylated using sizing and methylation status analyses, respectively, yielding a disease prevalence of 1.83%.CONCLUSIONRepeat expansion and methylation-specific TP-PCR is practical, effective and inexpensive for the diagnosis of FXS, especially in high-risk populations of individuals with ID of undetermined aetiology.  相似文献   
8.
目的 探讨益气活血通络方对糖尿病神经病理性疼痛(diabetic neuropathic pain,DNP)的影响及其作用机制。方法 高脂喂养大鼠4周后,35 mg/kg链脲佐菌素(streptozotocin,STZ)腹腔注射复制2型糖尿病大鼠模型,通过观测大鼠机械痛阈和热缩足反应时间作为判定DNP模型复制成功的标准。将DNP大鼠随机分为模型组,益气活血通络方高、中、低剂量组和阳性对照组(甲钴胺),另设空白对照组。Western blot法和免疫荧光双标检测脊髓中补体受体- 3的单克隆抗体(monoclonal antibody of complement receptor type 3,OX42)和P2X7(purinergic 2X7)的表达水平;ELISA法检测血清肿瘤坏死因子- α(tumor necrosis factor- α,TNF- α)、白细胞介素- 1β(interleukin- 1β,IL- 1β)和趋化因子配体3(CC- chemokine ligand 3,CCL3)水平。结果 益气活血通络方干预后,DNP大鼠的机械痛阈和热缩足反应时间均得到显著的改善;大鼠血清TNF- α、IL- 1β和CCL3水平显著降低(P<0.05);脊髓组织中OX42和P2X7表达水平均显著降低(P<0.05)。结论 益气活血通络方对DNP大鼠具有显著的治疗作用,其作用机制可能是通过抑制脊髓小胶质细胞活性,调节P2X7的表达,从而减轻神经炎症反应。  相似文献   
9.
目的 探讨肺部超声和胸部X线对新生儿呼吸窘迫综合征的诊断效能。方法 选择2020年3月至2021年3月我院收治的160例高度疑似呼吸窘迫综合征新生儿,所有患儿均接受肺部超声及胸部X线诊断。以临床最终诊断结果为金标准,分析肺部超声及胸部X线对新生儿呼吸窘迫综合征的诊断效能。结果 160例高度疑似呼吸窘迫综合征新生儿中, 74例(46.25%)经临床最终确诊为新生儿呼吸窘迫综合征。肺部超声、胸部X线诊断新生儿呼吸窘迫综合征与临床最终诊断结果的κ值分别为0.924 (一致性较好)、 0.725 (一致性一般)。肺部超声诊断新生儿呼吸窘迫综合征的敏感度、特异度及准确度均高于胸部X线(P<0.05)。结论 与胸部X线相比,肺部超声诊断新生儿呼吸窘迫综合征的准确度、特异度及敏感度更高,值得临床推广应用。  相似文献   
10.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
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