A First-Principles Study on the Hydration Behavior of (MgO)n Clusters and the Effect Mechanism of Anti-Hydration Agents

Magnesia-based refractory is widely used in high-temperature industries; its easy hydration is, however, a key concern in refractory processing. Understanding the hydration mechanism of MgO will help in solving its hydration problem. Herein, the hydration behavior of (MgO)_n (n = 1–6) at the molecular level and the effect mechanisms of several anti-hydration agents on the hydration of (MgO)₄ were investigated with first-principles calculations. The results indicated that the following: (1) The smaller the (MgO)_n cluster size, the more favorable the hydration of MgO and the tendency to convert into Mg(OH)₂ crystal; (2) Anti-hydration agents can coordinate with the unsaturated Mg atom of (MgO)₄ to form a bond, increasing the coordination number of Mg, thus reducing its activity when reacting with H₂O; (3) The greater the number of −COOH groups and the longer the chain length in the anti-hydration agents, the better its effect of inhibiting the hydration of MgO. These findings could enhance the understanding of the mechanism of hydration of MgO and provide theoretical guidance for the design of novel anti-hydration agents.     

Vitamin D Status Presents Different Relationships with Severity in Metabolic-Associated Fatty Liver Disease Patients with or without Hepatitis B Infection

Whether the associations between serum vitamin D (VitD) and metabolic-associated fatty liver disease (MAFLD) vary with chronic hepatitis B (CHB) infection has not been well established. This study aims to investigate the relationships between serum VitD and metabolism, liver fat content (LFC) and fibrosis among MAFLD patients with and without CHB. Consecutive subjects (healthy controls: 360, CHB: 684, MAFLD: 521, CHB with MAFLD: 206) were prospectively enrolled between January 2015 and December 2021. Anthropometric, laboratory, imaging, and histological evaluations were conducted, with LFC measured via magnetic resonance imaging-based proton density fat fraction (MRI-PDFF). Serum VitD levels were lower in MAFLD patients than in healthy controls and patients with CHB alone or overlapping with MAFLD (24.4 ± 8.1 vs. 29.0 ± 9.5 vs. 27.4 ± 9.6 vs. 26.8 ± 8.4 ng/mL respectively; p < 0.001 in one-way ANOVA test). After adjusting for confounding factors, including season, hypersensitive C-reactive protein, insulin resistance, liver stiffness measurements, sun exposure, exercise and dietary intake, multivariate linear regression analysis revealed that VitD remained significantly negatively correlated with LFC in MAFLD patients (β = −0.38, p < 0.001), but not in CHB with MAFLD patients. Moreover, quantile regression models also demonstrated that lower VitD tertiles were inversely associated with the risk of insulin resistance and moderate–severe steatosis in the MAFLD group (p for trend <0.05) but not in the MAFLD with CHB group. VitD deficiency was associated with the severity of metabolic abnormalities and steatosis independent of lifestyle factors in MAFLD-alone subjects but not in MAFLD with CHB subjects.     

内侧开放楔形胫骨高位截骨术治疗膝关节内侧单间室骨关节炎后的足底压力分析

目的 分析内侧单间室膝关节骨性关节炎(knee osteoarthritis, KOA)患者接受内侧开放楔形胫骨高位截骨术(medial opening wedge high tibial osteotomy, MOWHTO)治疗后的足底压力分布情况,为患者的手术治疗和康复提供生物力学参考。方法 选取31例行单侧MOWHTO治疗后的内侧单间室KOA患者作为实验组,同时以35例同年龄健康人群作为对照组,使用Pedomedic 40^?足底压力测试系统进行动态足底压力的测试。通过比较步行状态下实验组(术侧及未术侧)与对照组不同足底分区的峰值压强(p_max)、压力时间积分(force-time integral, FTI)和接触面积(contact area, CA),评估内侧单间室KOA患者MOWHTO术后的足底压力变化。结果 与未术侧和对照组相比,术侧第1跖骨区(MH1)CA和FTI偏高(P<0.05),第4跖骨区(MH4)CA偏小(P<0.001),第5跖骨区(MH5)p_max和FTI偏小(P<0.05)...     

男男性行为者艾滋病暴露前预防用药性行为去抑制化情况

目的：了解男男性行为者（men who have sex with men,MSM）在参加暴露前预防用药（pre-exposure prophylaxis,PrEP）临床试验中是否存在性行为去抑制化现象及其影响因素。方法：采用非概率抽样法招募并筛选出108名MSM,随机分为77名服用药物组和31名空白对照组,第12、24、36、48周进行临床随访和问卷调查,问卷调查主要包括社会人口学特征,艾滋病相关知识、态度和行为等相关情况。采用单因素和多因素的广义估计方程分析MSM在参与PrEP中是否存在性行为去抑制化现象及其影响因素。结果：药物服用组MSM在参与PrEP的第12、24、36、48周的性伴个数中位数分别为1（0,6）、1（0,6）、1（0,10）、1（0,3）、1（0,3）,高危性行为次数中位数分别为1（0,26）、1.5（0,8）、1（0,12）、1（0,9）、2（0,30）;空白对照组性伴个数中位数分别为1（0,21）、1（0,2）、1（0,3）、1（0,3）、1（0,3）,高危性行为次数中位数分别为1（0,9）、1（0,6）、0.5（0,15）、0（0,10）、1（0,10）;多因素广义估计方程分析发现MSM在参与PrEP过程中性伴个数及高危性行为次数均没有发生改变（Z=-0.24,P=0.811;Z=0.93,P=0.355）,性行为方式为“1”和“0.5”的较性行为方式为“0”的拥有更多的性伴（Z=2.47,P=0.014;Z=2.24,P=0.025）;发生过商业性行为的MSM较没有发生过的拥有较少的性伴和高危性行为（Z=-2.82,P=0.005;Z=-2.28,P=0.023）;已婚较离异MSM发生较少的高危性行为次数（Z=-2.34,P=0.019）。结论：本研究中暂未发现PrEP中存在性行为去抑制化现象,性行为方式为“1”和“0.5”的MSM拥有较多性伴,是后期随访中的重点管理人群。还需进一步加强对艾滋病相关知识的科普。     

重庆喀斯特地区金银花的生物学特性及规范化种植技术研究

为促进金银花种植技术在广大喀斯特地区顺利推广,促进中药材产业的顺利发展,并促进喀斯特地区生态顺利恢复,结合喀斯特地区生态恢复技术研究项目的 开展,开展了金银花主要品种忍冬在喀斯特地区的生物学特性研究、生态作用分析和规范化种植技术研究,形成了较为系统金银花规范化种植技术体系,主要包括育苗、移栽、田间管理、病虫害防治及加工...     

补肾药物穴位给药治疗骨质疏松症的机理探讨

骨质疏松症是临床常见病多发病。随着人口老龄化的进展,骨质疏松的患病率逐年增加。目前国内外主要应用药物(包括西药和中药)疗法,其研究开展的较早也较系统,已取得了较大的进展,药理学研究多局限于口服药物和注射药物的研究。近年来,伴随着透皮剂和离子导入等理化技术的发展,中药经皮给药治疗骨质疏松症已取得一定进展。就此方面对补肾药物经皮穴位给药治疗骨质疏松症的机理作一探讨。     

去卵巢对大鼠泪腺中IL-17A等炎症因子表达的影响

目的建立去卵巢大鼠模型,观察性激素水平改变对泪腺中IL-17A以及IL-1β、IL-6、TNF-α等炎症因子表达的影响。方法实验研究。健康雌性SD大鼠20只随机分为2组,实验组（10只）摘除大鼠双侧卵巢,对照组（10只）为未摘除卵巢的模拟手术组。术前及术后第1个月、第2个月、第3个月时2组均行泪液分泌试验（SIT）、角膜荧光染色检查进行眼表评估。于第3个月时放射免疫分析法分别检测2组大鼠血清雌二醇、睾酮含量,HE染色观察泪腺上皮细胞形态,免疫组化染色法、Western Blot法检测2组泪腺中IL-17A、IL-1β、IL-6、TNF-α的表达。2组性激素质量浓度比较、炎症因子A值表达比较均应用独立样本t检验。2组各时间点的SIT结果比较采用重复测量资料两因素方差分析。结果实验组大鼠去卵巢后第3个月时,体内雌二醇浓度低于对照组（t=-35.37,P<0.01）,睾酮浓度低于对照组（t=-12.13,P<0.01）。2组各时期SIT检查未见泪液分泌减少、均未见角膜荧光染色。HE染色见实验组泪腺腺泡萎缩,排列紊乱,胞质内酶原颗粒明显减少。泪腺IL-17A表达量2组比较实验组高于对照组（免疫组化法：t=7.56,P<0.01;Western Blot法：t=20.90,P<0.01）。余各因子表达量实验组也均高于对照组（免疫组化法：IL-1β：t=13.71,P<0.01;IL-6：t=13.92,P<0.01;TNF-α：t=6.11,P<0.01。Western Blot法：IL-1β：t=16.93,P<0.01;IL-6：t=12.46,P<0.01;TNF-α：t=14.47,P<0.01）。结论大鼠去卵巢3个月时性激素水平降低,未见明显眼表损害。但泪腺中炎症因子IL-17A、IL-1β、IL-6、TNF-α的表达增加。     

前列腺疾病患者血清TPSA、FPSA和PAP的检测及其意义

为探讨总前列腺特异性抗原 (TPSA)、游离前列腺特异性抗原 (FPSA)、前列腺酸性磷酸酶 (PAP)的检测对前列腺疾病的诊断价值 ,采用双抗体夹心酶联免疫 (ELISA)法对 3 8例前列腺癌、85例前列腺良性疾病和 40例正常人血清中 TPSA、FPSA和PAP水平进行了检测。结果显示 ,前列腺癌患者血清中 TPSA、 FPSA和 PAP水平均显著高于前列腺良性疾病组和正常对照组 (P<0 .0 1) ,F/ T比值前列腺癌组明显低于前列腺良性疾病组和正常组 (P<0 .0 1) ,前列腺良性疾病组与正常组无明显差别。     

Schiff碱型r-氨基丁酸酯类衍生物的合成及其抗惊厥活性

作者设计并合成了9个Schiff碱型取代对羟基本甲醛缩r-氨基丁酸酯类化合物。并用美国NIH提出的“抗癫痫药物开发程序(ADD)对所合成的化合物进行抗惊厥活性筛选。结果表明化合物Ⅲf、Ⅲg、Ⅲh、Ⅲi具有不同程度的抗惊厥活性。