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61.
Alzheimer’s disease (AD) is the most common cause of dementia, accounting for more than 50 million patients worldwide. Current evidence suggests the exact mechanism behind this devastating disease to be of multifactorial origin, which seriously complicates the quest for an effective disease-modifying therapy, as well as impedes the search for strategic preventative measures. Of interest, preclinical studies point to serotonergic alterations, either induced via selective serotonin reuptake inhibitors or serotonin receptor (ant)agonists, in mitigating AD brain neuropathology next to its clinical symptoms, the latter being supported by a handful of human intervention trials. Additionally, a substantial amount of preclinical trials highlight the potential of diet, fecal microbiota transplantations, as well as pre- and probiotics in modulating the brain’s serotonergic neurotransmitter system, starting from the gut. Whether such interventions could truly prevent, reverse or slow down AD progression likewise, should be initially tested in preclinical studies with AD mouse models, including sufficient analytical measurements both in gut and brain. Thereafter, its potential therapeutic effect could be confirmed in rigorously randomized controlled trials in humans, preferentially across the Alzheimer’s continuum, but especially from the prodromal up to the mild stages, where both high adherence to such therapies, as well as sufficient room for noticeable enhancement are feasible still. In the end, such studies might aid in the development of a comprehensive approach to tackle this complex multifactorial disease, since serotonin and its derivatives across the microbiota-gut-brain axis might serve as possible biomarkers of disease progression, next to forming a valuable target in AD drug development. In this narrative review, the available evidence concerning the orchestrating role of serotonin within the microbiota-gut-brain axis in the development of AD is summarized and discussed, and general considerations for future studies are highlighted.  相似文献   
62.

Background

Poland introduced the 10-valent conjugate pneumococcal vaccine (PCV10) into the childhood immunization program in January 2017. During previous decades, considerable changes had occurred in the surveillance system for invasive pneumococcal disease. Therefore, to provide baseline data on pneumococcal diseases before PCV10 introduction, we evaluated the epidemiology of pneumococcal meningitis (PM), the only syndrome monitored consistently since 1970.

Methods

Based on laboratory-confirmed cases reported during 2005-2015, we calculated the reported rates, serotypes distribution and antimicrobial resistance of pneumococcal meningitis isolates. Data from the mandatory national surveillance system was linked with data on cerebrospinal fluid isolates submitted to the National Reference Centre for Bacterial Meningitis. We used negative binomial regression with Newey West method to test for trend in rates of pneumococcal meningitis notified during 2005-2015 and Chi-squared test to assess changes in the serotype distribution from 2008-2011 to 2012-2015.

Results

From 2005 to 2015, the overall reported incidence of PM increased from 0.21 to 0.47 cases per 100,000 population, average yearly increase of 7% (rate ratio 1.07; 95% CI 1.06–1.08). The increase was primarily due to annual increase of 3% (1.02–1.05) among 15–49?years of age, 12% (95% CI: 1.10–1.13) among 50–64?years of age, 18% (95% CI: 1.16–1.19) among persons 65–74?years of age and 9% (95% CI 1.07–1.10) among persons ≥75?years of age. In children <5?years of age, serotypes included in PCV10 and PCV13 accounted for 75% and 80% of reported isolates, respectively. From 2008-2011 to 2012-2015, the proportion of PM cases caused by PCV10 serotypes decreased from 52% to 41% (p?<?0.01). Overall, 28% of isolates were resistant to penicillin and 13% were non-susceptible to cefotaxime.

Conclusions

The introduction of PCV10 into national immunization program may have considerable impact on disease burden, especially on number of cases caused by isolates non-susceptible to antimicrobials.  相似文献   
63.
目的:探讨miR-145调控肝癌腹水模型Th9细胞升高的作用机制。方法:构建小鼠H22肝癌腹水模型。造模两周后处死小鼠并分离出脾脏组织,流式细胞术分析肝癌腹水组(MA组)与正常对照组(Control 组)小鼠脾脏Th9细胞表达水平。ELISA法检测脾脏IL-9表达水平。RT-PCR法检测脾脏miR-145表达水平。Western Blot法检测脾脏中PI3K/Akt/mTOR/P70S6K/HIF-1α相关蛋白表达水平。分选小鼠脾脏CD4+T细胞,随机分为miR-145 mimics组和NC组,分别应用miR-145-5P mimics、阴性对照寡核苷酸(negative control,NC)进行转染,RT-PCR检测各组miR-145、HIF-1α mRNA及IL-9 mRNA表达水平。结果:与Control 组相比,MA组Th9细胞及其细胞因子IL-9表达均升高(P<0.05),miR-145表达降低(P<0.05),p-PI3K、p-Akt、mTOR、p-mTOR、p-P70S6K、HIF-1α蛋白均升高(P<0.05)。与NC组相比,miR-145 mimics组miR-145显著升高,HIF-1α mRNA及IL-9 mRNA表达下降。结论:肝癌腹水中Th9细胞升高可能与miR-145下降导致的PI3K/Akt/mTOR/P70S6K/HIF-1α通路激活有关。  相似文献   
64.
Telomeric repeat‐containing RNA (TERRA) is closely involved in the regulation of telomere length, which plays critical roles in tumorigenesis. However, the biological significance of TERRA in hepatocellular carcinoma (HCC) remains largely unknown. In this study, we found that HCC cells show a frequent downregulation of TERRA and its positive regulator TTAGGG repeat binding factor‐1 (TRF1), whereas the negative regulator TTAGGG repeat binding factor‐1 (TRF2) was upregulated. We found that TERRA, TRF1, and TRF2 contributed to poor prognosis of HCC patients. Importantly, we found that the downregulation of TERRA significantly promoted HCC cell growth and metastasis in vitro and in vivo, whereas the upregulation of TERRA showed an opposite effect. Mechanistically, downregulation of TERRA significantly increased telomerase activity and promoted telomere elongation. Moreover, the inhibitory effects of TERRA overexpression on the growth and metastasis of HCC cells were reversed by treatment with TA‐65 that activates telomerase activity. In contrast, the protumor effect of TERRA downregulation was reversed by treatment with TMPyP4 that inhibits telomerase activity. Our findings reveal that TERRA plays a critical role in HCC cell growth and metastasis, indicating that TERRA is a potential therapeutic target for HCC.  相似文献   
65.
目的观察肛窦炎应用针刺配合肠炎散保留灌肠治疗的效果。方法选取2017年10月-2018年10月就诊的72例肛窦炎患者,采用随机数字表法分为观察组(n=36)与对照组(n=36)。对照组给予肠炎散保留灌肠治疗,观察组为针刺配合肠炎散保留灌肠治疗,比较2组症状、疗效及安全性。结果观察组症状(放射痛、指诊症状及镜检症状)少于对照组,总有效率高于对照组,差异有统计学意义(P<0.05);2组安全性相比,差异无统计学意义(P>0.05)。结论针对肛窦炎患者,予以针刺配合肠炎散保留灌肠治疗效果确切,可减少临床症状,加快疾病转归,且治疗安全性较好。  相似文献   
66.
67.
目的观察旋覆代赭汤对反流性食管炎(RE)模型大鼠食管黏膜与脂多糖(LPS)、Toll样受体4(TLR4)、核因子κB(NF-κB)表达的影响。方法将60只雄性Wistar大鼠按随机数字表法分为正常对照组、模型组、旋覆代赭汤组(简称中药组,9.89 g/kg)、西药(奥美拉唑+莫沙比利,2.58 mg/kg)组,每组15只。除正常对照组外大鼠采用“4.2 mm幽门夹+2/3胃底结扎术”制备酸碱混合反流RE大鼠模型。术后第7天予相应药物干预,持续干预14天。利用光学显微镜观察大鼠食管下段黏膜组织形态学变化;应用ELISA法检测定外周血中LPS含量;采用Western Blot法与RT-PCR法检测食管黏膜组织中TLR4、NF-κB蛋白和基因表达。结果与正常对照组比较,模型组大鼠食管黏膜镜下损伤最为严重,食管黏膜呈炎性改变,可见急慢性炎细胞浸润,病理积分和外周血中LPS含量升高(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达升高(P<0.05)。与模型组比较,中药组、西药组病理积分和外周血中LPS含量降低(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达亦明显降低(P<0.05)。结论旋覆代赭汤能够减轻RE模型大鼠食管黏膜的损伤,抑制TLR4、NF-κB的表达,促进食管黏膜损伤的恢复。  相似文献   
68.
目的 探讨鼻腔菌群失调与结外NK/T细胞淋巴瘤(extranodal NK/T-cell lymphoma,ENKTCL)预后的相关性。方法 回顾性分析244例初治ENKTCL患者的临床资料及鼻拭子培养结果,根据是否存在鼻腔菌群失调将患者分为菌群正常组(n=114)和菌群失调组(n=130),并分析菌群失调与患者临床病理特征、治疗效果及预后的关系。结果  菌群失调组患者共培养出409株优势菌株,以金黄色葡萄球菌、草绿色链球菌、表皮葡萄球菌及铜绿假单胞菌为主。菌群失调组患者的乳酸脱氢酶升高比例高于菌群正常组(P=0.044),预后评分PINK≥1的中危或高危患者比例亦高于菌群正常组(P=0.003)。治疗结束时,菌群失调组患者的完全缓解率显著低于菌群正常组(45.5% vs 61.4%,P<0.05),5年无疾病进展生存率亦低于菌群正常组(48.4% vs 63.9%,P=0.048)。亚组分析显示,早期及PINK低危患者中,菌群失调与否与患者的无疾病进展生存期有关(P=0.022, 0.011)。结论 鼻腔菌群失调与ENKTCL患者预后密切相关,针对鼻腔菌群失调的措施可能进一步改善ENKTCL的治疗效果及预后。  相似文献   
69.
手术切除是胸腺瘤最重要的治疗手段,然而,术后辅助放疗的作用一直存在不同争议。二维放疗时代多数获益不明显,精准放疗技术已使肿瘤放疗发生了较大的变化,胸腺瘤术后放疗价值也可能在改变。目前,放疗在手术切缘阳性或无法行手术切除者的作用是肯定的;在完整手术切除者中,Masaoka-Koga分期Ⅰ期患者无需术后辅助放疗,Ⅱ期患者术后辅助放疗作用争议较大,如果放疗宜考虑Ⅱb期、大体积、B2/B3型等因素;Ⅲ期术后辅助放疗也存在争议,但是多数结果倾向行术后放疗。术后辅助放疗宜采用精准放疗技术,照射范围建议瘤床三维外扩0.5 cm,肿瘤累及的纵隔胸膜及沿纵隔胸膜前后、头脚方向0.5~1.0 cm,肺侧纵隔胸膜为0.5 cm以内,以及肿瘤周血管壁和部分血管间隙,避免包括过多的正常组织。剂量在完全切除时为45~50Gy,非完全切除为54~60Gy或稍高,可能会使放疗获益增加和风险下降。质子、重离子等新型放疗技术的应用可获得剂量学方面的优势,是否能转化为临床获益还需进一步探究。  相似文献   
70.
目的:探讨 circRNA_001569 通过 miR-145/HBXIP 轴在乳腺癌细胞增殖、侵袭、迁移中发挥的作用。方法:收集2016年1月至2019年1月期间衡水市人民医院收治的30例乳腺癌患者的癌组织和癌旁组织。qPCR检测circRNA_001569在乳腺癌组织、癌旁组织以及细胞系中的表达。生物信息学工具预测miR-145的靶基因,RNA免疫沉淀(RNA immunoprecipitation,RIP)和双荧光素酶报告基因实验检测 miR-145 或靶基因之间的相互作用 ;向乳 腺 癌 MDA-MB-231 和 MCF-7细胞中转染si-circRNA_001569、miR-145 mimics或miR-145 inhibitor,建立基因过表达或沉默的细胞模型,qPCR和Western blotting分别检测转染对相关基因和蛋白表达的影响,CCK-8法、Transwell实验检测转染对细胞增殖、侵袭和迁移的影响。结果:在乳腺癌组织和乳腺癌细胞中,circRNA_001569 和 HBXIP 均呈高表达、miR-145 呈低表达。RIP 分析和双荧光素酶实验证实了 miR-145 与circRNA_001569和HBXIP之间的靶向关系;circRNA_001569或HBXIP过表达促进MDA-MB-231和MCF-7细胞的增殖、侵袭和迁移(均 P<0.01),而 miR-145 过表达起相反的作用(均 P<0.01)。结论:circRNA_001569 可能通过下调 miR-145 的表达、上调HBXIP的表达从而促进乳腺癌细胞的增殖、侵袭和迁移。  相似文献   
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