骨巨细胞瘤中 nm23 和 ras 基因的表达及临床意义

目的 :探讨nm2 3和ras基因在骨巨细胞瘤 (GCT)的表达及与GCT病理分级和复发的关系。方法 :应用SP免疫组织化学方法检测nm2 3和ras在 52例GCT (GCT按Jaffe分级 :Ⅰ级 15例、Ⅱ级2 5例、Ⅲ级 12例 )中的表达。结果 :2 1例nm2 3表达阳性 ,阳性率 4 0 .4 % ,7例ras表达呈阳性 ,阳性率13.5%。其阳性表达与病理分级均无显著相关性 (P >0 .0 5)。nm2 3和ras在复发和无复发的病例中 ,阳性表达率分别为 6 9.2 %、30 .8%和 2 3.1%、10 .3%。nm2 3过表达与GCT复发有高度相关性 (P <0 0 5)。而ras基因表达无相关性。结论 :nm2 3和ras表达均与GCT病理分级无关。nm2 3表达与肿瘤复发有关 ,而ras表达与复发未见相关性     

晚期糖化终末产物对大鼠成骨细胞增殖和分化的影响

目的　通过探讨晚期糖化终末产物（ Ａｄｖａｎｃｅｄ ｇｌｙｃｏｓｙｌａｔｉｏｎ ｅｎｄｐｒｏｄｕｃｔｓ Ａ Ｇ Ｅｓ）对大鼠成骨细胞增殖和分化的影响,以期揭示老年性骨质疏松症的发病机理。方法　体外合成 Ａ Ｇ Ｅｓ 以不同浓度加入成骨细胞培养体系,作用不同时间后,用 Ｍ Ｔ Ｔ 法测定细胞增殖活性,通过测定碱性磷酸酶观察成骨细胞的分化。结果　较低剂量 Ａ Ｇ Ｅｓ 在不同的培养时间均显著促进大鼠成骨细胞增殖。较高剂量（８００ μｇ／ｍ ｌ～１ ０００ μｇ／ｍ ｌ）只有在培养２４小时具有促增殖作用。低剂量 Ａ Ｇ Ｅｓ 促进成骨细胞分化,中等剂量促分化作用延迟,高剂量无促分化活性。结论　过多的 Ａ Ｇ Ｅｓ 相对降低成骨细胞的数量和活性,使骨形成作用小于骨吸收作用,导致骨质疏松     

Colistin: from the shadows to a One Health approach for addressing antimicrobial resistance

Antimicrobial resistance (AMR) poses a serious threat to human, animal and environmental health worldwide. Colistin has regained importance as a last-resort treatment against multi-drug-resistant Gram-negative bacteria. However, colistin resistance has been reported in various Enterobacteriaceae species isolated from several sources. The 2015 discovery of the plasmid-mediated mcr-1 (mobile colistin resistance) gene conferring resistance to colistin was a major concern within the scientific community worldwide. The global spread of this plasmid – as well as the subsequent identification of 10 MCR-family genes and their variants that catalyse the addition of phosphoethanolamine to the phosphate group of lipid A – underscores the urgent need to regulate the use of colistin, particularly in animal production. This review traces the history of colistin resistance and mcr-like gene identification, and examines the impact of policy changes regarding the use of colistin on the prevalence of mcr-1-positive Escherichia coli and colistin-resistant E. coli from a One Health perspective. The withdrawal of colistin as a livestock growth promoter in several countries reduced the prevalence of colistin-resistant bacteria and its resistance determinants (e.g. mcr-1 gene) in farm animals, humans and the environment. This reduction was certainly favoured by the significant fitness cost associated with acquisition and expression of the mcr-1 gene in enterobacterial species. The success of this One Health intervention could be used to accelerate regulation of other important antimicrobials, especially those associated with bacterial resistance mechanisms linked to high fitness cost. The development of global collaborations and the implementation of sustainable solutions like the One Health approach are essential to manage AMR.     

Understanding the impact of radical changes in diet and the gut microbiota on brain function and structure: rationale and design of the EMBRACE study

BackgroundBariatric surgery leads to profound changes in gut microbiota and dietary patterns, both of which may interact to impact gut-brain communication. Though cognitive function improves postsurgery, there is a large variability in outcomes. How bariatric surgery-induced modifications in the gut microbiota and dietary patterns influence the variability in cognitive function is still unclear.ObjectivesTo elucidate the associations between bariatric surgery-induced changes in dietary and gut microbiota patterns with cognition and brain structure.SettingUniversity hospital.MethodsA total of 120 adult patients (≥30 years) scheduled to undergo a primary bariatric surgery along with 60 age-, sex-, and body mass index-matched patients on the surgery waitlist will undergo assessments 3-months presurgery and 6- and 12-month postsurgery (or an equivalent time for the waitlist group). Additionally, 60 age-and sex-matched nonbariatric surgery eligible individuals will complete the presurgical assessments only. Evaluations will include sociodemographic and health behavior questionnaires, physiological assessments (anthropometrics, blood-, urine-, and fecal-based measures), neuropsychological cognitive tests, and structural magnetic resonance imaging. Cluster analyses of the dietary and gut microbiota changes will define the various dietary patterns and microbiota profiles, then using repeated measures mixed models, their associations with global cognitive and structural brain alterations will be explored.ResultsThe coordinating study site (Centre intégré universitaire de santé et de services sociaux du Nord-de-l’Île-de-Montréal, QC, Canada), provided the primary ethical approval (Research Ethics Board#: MP-32-2022-2412).ConclusionsThe insights generated from this study can be used to develop individually-targeted neurodegenerative disease prevention strategies, as well as providing critical mechanistic information.     

未知基因KH与公共生物信息资源的比较与分析

目的 快速分析K562细胞中未知基因KH的结构与功能。方法 以mRNA差异显示技术筛选的K562细胞在0．2mg／ml苦参碱诱导前、后3小时的差异基因为研究对象，采用基因片段的碱基序列与Internet网上多种公共生物信息数据库进行比较，分析未知基因KH的结构与功能。结果 对其中的4个片段进行序列分析和同源性比较，有3个基因片段与已知蛋白或蛋白酶的碱基序列完全或高度同源；有1个基因片段除与16号染色体高度同源外，与其它数据库均无显著同源性，暂命名KH基因。结论 KH基因可能是苦参碱作用K562细胞后表达量发生改变的候选新基因。