The effect of dietary vitamin D metabolites and zinc on normal and ectopic bone formation in weanling rats

The effect of dietary supplementation of rats with vitamin D metabolites and zinc was examined in selected bones and a short-term in vivo implant model. A 2×2×3 factorial design was utilized with two vitamin D metabolites (cholecalciferol-D₃ or 1,25-dihydroxycholecalciferol-1,25(OH)₂D₃); two levels of dietary zinc (marginal-4.5, and adequate-10 ug/g diet); and three time periods (11, 14 and 21 days after implantation). Seventy-two female weanling Long-Evans rats were fed their respective diets for three weeks before subcutaneous implantation with demineralized bone powder. The animals were injected intraperitoneally with ⁴⁵Ca (0.5uCi/g body weight) 14 h before sacrificing. The ectopic bone implants as well as the femurs, tibias, humeri, scapulas and mandibles were obtained 11, 14 and 21 days following implantation. Implants were fixed, sectioned and stained with toluidine blue. The specific bones and the implants were analyzed for calcium, zinc and ⁴⁵Ca. There was higher calcium concentration in the femurs of animals fed D₃ compared to 1,25(OH)₂D₃. Activities of enzymes (alkaline phosphatase-marker for formation, and acid phosphatase-marker for resorption) were quantitated in the implants. Enzyme activities, mineral deposition and presence of osteoblasts and osteoclasts all provided definitive evidence that the implant system was mimicking the typical dynamic processes normally occurring in bone tissues. An interaction between the form of vitamin D (D₃ vs 1,25(OH)₂D₃) and level of zinc fed to the rats was demonstrated in the implants; calcium and zinc concentrations were higher in the implants of rats fed D₃ and adequate zinc than rats fed 1,25(OH)₂D₃ and adequate zinc. In summary, adequate dietary zinc concentration modulates the effects of vitamin D metabolites; also D₃ form has a greater anabolic effect on integrity of the bone than 1,25(OH)₂D₃. Furthermore, femur appears to be more sensitive than the other bones tested to changes in calcium concentration due to the two forms of vitamin D.     

VITAMIN D METABOLISM IN THE RICKETS OF VERY-LOW-BIRTH-WEIGHT, PREMATURE INFANTS

The circulating 1,25-dihydroxyvitamin D₃ levels in a very-low-birth-weight, premature infant who developed florid rickets was markedly elevated. Treatment with additional, oral 1,25-(OH)₂D₃ corrected the biochemical abnormalities and hastened healing of the rachitic lesions.     

A Potential Role for Vitamin D on HIV Infection?

Despite advances in the knowledge of vitamin D's potent immunomodulatory activity, its role on HIV disease progression is unknown. Decreased concentrations of 1α,25-hydroxyvitamin D₃, or 1,25(OH)₂D, the active form of vitamin D, have been reported among HIV-infected people and attributed to defects in renal hydroxylation and increased utilization. A few studies also described low levels of 25-hydroxyvitamin D₃, 25(OH)D, the vitamin obtained from solar synthesis and diet. An inverse association between 1,25(OH)₂D concentrations and mortality has been reported from a small cohort of HIV-infected adults, and some cross-sectional studies have indicated positive correlations between 1,25(OH)₂D and CD4+ cell counts. Additional observational studies are needed to confirm the associations between vitamin D status and HIV disease progression. These investigations would provide useful insights on the potential role of vitamin D supplementation to HIV-infected persons and the planning of intervention trials.     

血清1,25-(OH)D_3水平与婴幼儿喘息的相关因素分析

目的研究血清1,25-(OH)D_3水平和总IgE水平在喘息婴幼儿中的表达及临床意义。方法随机选取2015年9月-2016年3月于本院住院的喘息患儿52例,依据哮喘预测指数分为哮喘预测指数阳性的喘息Ⅰ组(n=29)和哮喘预测指数阴性的喘息Ⅱ组(n=23),对照组为本院门诊健康体检儿童(n=23)。分别测定3组患儿血清1,25-(OH)D_3和总IgE水平。结果喘息Ⅰ组和喘息Ⅱ组患儿血清1,25-(OH)D_3水平均低于对照组,差异有统计学意义(P0.05),喘息Ⅰ组1,25-(OH)D_3水平低于喘息Ⅱ组(P0.05),喘息Ⅰ组IgE水平高于喘息Ⅱ组和对照组,差异有统计学意义(P0.05),喘息Ⅱ组和对照组之间差异无统计学意义(P0.05);喘息Ⅰ组血清1,25-(OH)D_3与IgE呈负相关性(r=-0.915,P0.01)。结论 1,25-(OH)D_3水平在有特应质的反复喘息儿童中显著降低,并且与总IgE水平呈负相关。     

Ascorbic acid effects on vitamin D hormone metabolism and binding in guinea pigs

Ascorbic acid deficiency in guinea pigs fed a vitamin D-replete diet caused a moderate reduction of Ca level in serum and bone; 25-hydroxy-cholecalciferol or 25-hydroxyergocalciferol (25-OHD) serum concentration tended to decline; renal 25-hydroxycholecalciferol-1-hydroxylase (1-OHase) activity decreased 50%; and 25-hydroxycholecalciferol-24-hydroxylase activity increased 1.6-fold. Chromatin 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] receptor concentration in the intestinal mucosa decreased 20-30%, and the percentage of occupied receptors decreased from 12-15% to 6-8%. Receptor affinity for 1,25-(OH)2D3 did not change (Kd = 0.24-0.26 nmol/L, Kd2 = 0.06-0.10 nmol/L), but the cooperativity coefficient decreased from 1.7 to 1.4. Vitamin C deficiency potentiated effects of vitamin D deprivation and impaired a restorative action of vitamin D. It was accompanied by a marked delay in the elevation of 25-OHD concentration in serum as well as decreased 1-OHase activity in kidneys and a lower concentration of occupied 1,25-(OH)2D3 receptors in the intestinal mucosa. The data demonstrate a critical role for ascorbic acid in vitamin D metabolism and binding.     

不同随访模式早产儿生后6至12月营养相关指标的对比研究

目的 监测规律随访与未规律随访模式早产儿生后6~12月间(矫正月龄)血清25-羟维生素D₃[25-(OH)D₃]、钙(Ca)、磷(P)、碱性磷酸酶(ALP)、尿素(UREA)、前白蛋白(PA)的水平,探讨两种随访模式对早产儿营养状况的影响及其安全性。方法 回顾性分析2015年1月-2017年12月在陆军军医大学第二附属医院院门诊就诊的143例早产儿资料,其中定期规律随访者79例设为A组,另外因各种原因未能定期规律随访者64例设为B组,同时将同期在本院儿保门诊随访的足月健康婴儿253例设为C组。婴儿于出生第6月至第12月(早产儿为矫正月龄)间抽血查血清25-(OH)D₃、Ca、ALP、P、UREA、PA水平。结果 1)A组及C组的血清25-(OH)D₃、Ca、PA均显著高于B组(P<0.05)。A组的血清25-(OH)D₃高于C组,差异具有统计学意义(P<0.05)。A、B、C三组间血清ALP、P、UREA差异无统计学意义(P>0.05)。2)A、B、C三组25-(OH)D₃测值评价结果比较:三组均无中毒病例,评价为25-(OH)D₃值适宜的例数A组最多,B组最少。结论 1)定期规律随访并按儿保建议喂养的早产儿,其生后6至12月血清25-(OH)D₃缺乏及低前白蛋白血症发生率低。2)早产儿喂养方案需个体化。3)部分早产儿营养评价指标(如:ALP)缺乏参考标准,仍需完善。     

Age-related alteration of vitamin D metabolism in response to low-phosphate diet in rats

The responses of renal vitamin D metabolism to its major stimuli alter with age. Previous studies showed that the increase in circulating 1,25-dihydroxyvitamin D (1,25(OH)2D3) as well as renal 25-hydroxyvitamin D3 1-alpha hydroxylase (1-OHase) activity in response to dietary Ca or P restriction reduced with age in rats. We hypothesized that the mechanism involved in increasing circulating 1,25(OH)2D3 in response to mineral deficiency alters with age. In the present study, we tested the hypothesis by studying the expression of genes involved in renal vitamin D metabolism (renal 1-OHase, 25-hydroxyvitamin D 24-hydroxylase (24-OHase) and vitamin D receptor (VDR)) in young (1-month-old) and adult (6-month-old) rats in response to low-phosphate diet (LPD). As expected, serum 1,25(OH)2D3 increased in both young and adult rats upon LPD treatment and the increase was much higher in younger rats. In young rats, LPD treatment decreased renal 24-OHase (days 1-7, P<0.01) and increased renal 1-OHase mRNA expression (days 1-5, P<0.01). LPD treatment failed to increase renal 1-OHase but did suppress 24-OHase mRNA expression (P<0.01) within 7 d of LPD treatment in adult rats. Renal expression of VDR mRNA decreased with age (P<0.001) and was suppressed by LPD treatment in both age groups (P<0.05). Feeding of adult rats with 10 d of LPD increased 1-OHase (P<0.05) and suppressed 24-OHase (P<0.001) as well as VDR (P<0.05) mRNA expression. These results indicate that the increase in serum 1,25(OH)2D3 level in adult rats during short-term LPD treatment is likely to be mediated by a decrease in metabolic clearance via the down-regulation of both renal 24-OHase and VDR expression. The induction of renal 1-OHase mRNA expression in adult rats requires longer duration of LPD treatment than in younger rats.     

不同糖耐量肥胖儿童血清硫化氢及25-羟基维生素D3水平变化研究

目的 研究不同糖耐量肥胖儿童血清硫化氢(H₂S)及25-羟基维生素D₃[25-(OH)D₃]水平的变化及意义,为临床治疗提供参考依据。方法 2013年1月-2016年1月收集204例口服葡萄糖耐量试验(OGTT)结果异常肥胖儿童的资料,根据OGTT结果将其分为空腹血糖受损(IFG)组、糖耐量受损(IGT)组、IFG合并IGT组以及糖尿病(DM)组。选择同期46例OGTT正常的肥胖儿童为单纯肥胖组,分别通过分光光度计法检测H₂S水平,酶联免疫法检测25-(OH)D₃水平。结果 IFG组、IGT组、IFG合并IGT组以及DM组血清H₂S及25-(OH)D₃水平均低于单纯肥胖组(P＜0.05);IFG合并IGT组血清H₂S及25-(OH)D₃均低于IFG组、IGT组(P＜0.05);DM组血清H₂S及25-(OH)D₃水平均低于IFG组、IGT组及IFG合并IGT组(P＜0.05);IFG组血清H₂S低于IGT组(P＜0.05)。DM组血清H₂S及25-(OH)D₃水平均低于单纯肥胖组(P＜0.05);IFG合并IGT组血清H₂S及25-(OH)D₃水平均低于单纯肥胖组(P＜0.05)。相关性分析中,单纯肥胖组、IFG组、IGT组、IFG合并IGT组以及DM组血清H₂S及25-(OH)D₃与0 h PG、2 h PG、HBALC水平均呈显著性负相关(all P＜0.05);单纯肥胖组、IFG组、IGT组、IFG合并IGT组以及DM组血清H₂S与25-(OH)D₃水平与呈显著正相关( P＜0.05)。结论 血清H₂S及25-(OH)D₃水平与肥胖儿童糖耐量情况密切相关,其水平的明显下降可能是肥胖儿童发展为2型糖尿病的危险因素。     

Comparison of 26,27-hexafluoro-1 alpha,25-dihydroxyvitamin D3 and 1 alpha,25-dihydroxyvitamin D3 on the resorption of bone explants ex vivo.

26,27-Hexafluoro-1 alpha,25-dihydroxyvitamin D3 [F6-1,25-(OH)2D3] is more potent than 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] in stimulating bone resorption in vitro and in vivo. The reason why F6-1,25(OH)2D3 is more active remains unclear. To clarify the relationship between the bone-resorbing activity of each vitamin D3 analogue and the metabolism of each analogue, in the present study, we used an ex vivo method that was established by Reynolds et al (Calcif Tissue Res, 1974, 15, 333-339). The effect of F6-1,25(OH)2D3 or 1,25(OH)2D3 on 45Ca release from parietal bones, prepared at 3, 14 and 24 h after injection of 1.9, 3.8, 7.6 or 15.2 pmol vitamin D analog/g body weight, was examined. F6-1,25(OH)2D3 was more potent than 1,25(OH)2D3 during each in vivo time period. 1,25(OH)2D3 at 3 h after the injection was more active compared to the control (no injection of 1,25(OH)2D3) but not at 14 and 24 h. The radioactivity of the bones after the injection of [3H]-F6-1,25(OH)2D3 was retained even at 24 h. In the case of [3H]-1,25(OH)2D3, the radioactivity of bones decreased with an increase in the in vivo period. In a HPLC analysis of the lipid extract of bone homogenate, [3H]-F6-1,25(OH)2D3 alone was detected at 3 h after the injection and both [3H]-F6-1,25(OH)2D3 and [3H]-26,27-hexafluoro-1 alpha, 23S,25-trihydroxyvitamin D3 [F6-1,23,25(OH)3D3] were detected at 14 and 24 h after the injection. [3H]-1,25(OH)2D3 was highly detected at 3 h after the injection, but it decreased with an increase in the in vivo period. In the ex vivo test, the activity of F6-1,23,25(OH)3D3 was less than that of F6-1,25(OH)2D3 but similar to that of 1,25(OH)2D3. The present study indicates that F6-1,25(OH)2D3 is more active and more long-lasting than 1,25(OH)2D3 in the ex vivo method. A higher potency of F6-1,25(OH)2D3 is explained, at least partly, by the results that the amounts of both F6-1,25(OH)2D3 and its active metabolite, F6-1,23,25(OH)3D3, in the bones are higher than that of 1,25(OH)2D3, and that F6-1,25(OH)2D3 and its metabolite are retained in bones longer than 1,25(OH)2D3.     

Efficacy of several vitamin D compounds in the prevention of tibial dyschondroplasia in broiler chickens

Studies were conducted to evaluate several cholecalciferol (D3 metabolites: 1,25-dihydroxycholecalciferol [1,25-(OH)2D3], 1,24R,25-trihydroxycholecalciferol [1,24R,25-(OH)3D3], 1 alpha-hydroxy-cholecalciferol (1 alpha-OHD3), 24R,25-dihydroxycholecalciferol [24R,25-(OH)2D3], 1,25-dihydroxy-26,27 hexadeuterium cholecalciferol (1,25-(OH)2-26,27[2H]6D3) and 1,25-dihydroxy-24R-fluorocholecalciferol [1,25-(OH)2-24R-FD3] for their activity in preventing the development of tibial dyschondroplasia in broilers. The basal diet used is low in calcium, high in phosphorus and chlorine and is known to promote a high incidence of tibial dyschondroplasia. The chicks received ultraviolet radiation from fluorescent lights in addition to 1100 ICU/kg (27.5 micrograms/kg) of D3 in the basal diet. Supplementation of the diet with 10 micrograms/kg of all the metabolites except 24R,25-(OH)2D3 significantly lowered the incidence and severity of tibial dyschondroplasia and increased bone ash when compared to birds receiving the basal diet. None of the active D3 metabolites was effective when fed at 0.1 or 1.0 micrograms/kg of diet. Two active compounds tested [1,25-(OH)2D3 and 1,24R,25-(OH)3D3] at 5 micrograms/kg of diet were effective in reducing either the incidence or severity of tibial dyschondroplasia.     

Effect of increasing doses of phenytoin on the plasma 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations

The circulating 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25-(OH)2D] concentrations were studied in a patient receiving increasing doses of phenytoin. The plasma 1,25(OH)2D concentrations were independent of the dose of phenytoin administered, as well as of the drug plasma concentrations. The plasma 25(OH)D concentrations were, on the other hand, increased by low phenytoin concentration but rapidly declined when the dose of phenytoin was increased and/or as the length of time of exposure to the drug increased. A linear relationship (R = 0.9651, P less than 0.05) was found between the plasma 25(OH)D concentrations and the dose/plasma phenytoin concentration ratio, suggesting that chronic phenytoin administration may have a dose-related effect on the circulating 25(OH)D concentrations.     

应用中断时间序列设计评估石家庄市流行性乙型脑炎疫苗防控效果

  目的  评估疫苗接种对流行性乙型脑炎(简称乙脑)发病趋势的影响。  方法  采用中断时间序列设计定量评估1949-2019年石家庄市乙脑年发病率变化趋势。  结果  1949-1968年,石家庄市乙脑发病率呈上升趋势(β₁=0.19, t=-2.01, P=0.048)。1969-2019年适龄人群疫苗接种,乙脑发病率当年下降(β₂=-7.83, t=-2.97, P=0.004);长期下降斜率均值(β₁+β₃)为-0.04/10万(t=-3.24, P=0.002);疫情暴发流行致人群发病率上升(β₄=3.87, t=2.36, P=0.007)。其中免疫规划前阶段(1969-2007年),接种当年发病率下降(β₂=-7.22, t=-2.98, P=0.019);持续长期下降斜率为0.29(t=-2.73, P=0.008);疫情暴发流行对人群发病率的影响无统计学意义(β₄=4.65, t=0.72, P=0.476)。免疫规划期(2008-2019年)与免疫规划前期相比,当年发病率下降程度无统计学意义(β₂=-2.89, t=-1.56, P=0.169);免疫规划期,发病率趋势无统计学意义(β₃=-0.03, t=-1.16, P=0.252);暴发流行升高了人群发病率(β₄=3.62, t=4.21, P=0.001)。  结论  疫苗接种致石家庄市乙脑疫情明显下降,防控效果显著。但受发病人群年龄后移影响,免疫策略也需调整。     

新生儿维生素D与血浆胰岛素及血糖水平的相关性研究

目的 研究新生儿血清维生素D(VitD)是否与空腹血浆胰岛素(INS)、C肽(CP)及血糖(GLU)水平之间存在相关性。方法 选取100例新生儿作为研究对象(其中足月儿58例,早产儿42例),检测血清25-羟基维生素D₂[25(OH)D₂]、血清25-羟基维生素D₃[25(OH)D₃]、血清25-羟基维生素D[25(OH)D]、空腹血浆胰岛素(INS)、C肽(CP)及血糖(GLU)浓度,采用SPSS 17.0对数据进行独立样本t检验和Pearson相关分析。结果 足月儿组血清25(OH)D₃、25(OH)D、空腹血浆INS、CP、空腹GLU浓度高于早产儿组,差异有统计学意义(P＜0.05)。足月儿血清25(OH)D₃、25(OH)D与空腹血浆INS、CP呈正相关(r=0.515,0.324,0.523,0.335,P＜0.05或<0.01),与空腹GLU呈负相关(r=-0.489,-0.514,P均＜0.01)。早产儿血清25(OH)D₃、25(OH)D与空腹血浆INS、CP呈正相关(r=0.509,0.367,0.598,0.432,P<0.05或＜0.01),与空腹GLU呈负相关(r=-0.539,-0.587,P均＜0.01)。结论 新生儿期血清VitD与空腹血浆INS、CP呈正相关,与空腹血糖呈负相关。     

血清维生素D水平与儿童哮喘的相关性研究

目的 观察哮喘儿童血清25-羟维生素D₃[25-(OH)D₃]浓度变化, 分析其与哮喘有关的血清总免疫球蛋白E(TIgE)含量、肺功能指标的相关性。方法 检测42例哮喘组、48例正常对照组儿童血清25-(OH)D₃、TIgE含量, 以及肺功能指标, 并进行组间比较分析。结果 与正常对照组比较, 哮喘组儿童血清25-(OH)D₃含量明显下降(P＜0.01), 而血清TIgE含量则明显升高(P＜0.01);哮喘组儿童血清25-(OH)D₃与TIgE呈负相关(P＜0.01), 与小气道用力呼气25%流量(MEF25)、用力呼气50%流量(MEF50)呈正相关(P＜0.05)。结论 维生素D缺乏是导致儿童哮喘发作的重要原因之一, 可能与25-(OH)D₃对TIgE产生抑制作用有关。     

基于分位数回归模型的2型糖尿病住院患者生命质量影响因素分析

  目的   了解银川市2型糖尿病((type 2 diabetes mellitus, T2DM)住院患者健康相关生命质量(health-related quality of life, HRQOL)现状, 分析影响T2DM住院患者HRQOL的因素; 探讨分位数回归分析HRQOL影响因素的应用价值。   方法   使用横断面调查的方法获得480例T2DM住院患者的资料, 采用中文版糖尿病相关生命质量(Chinese normal audit of diabetes-dependent quality of Life, CN-ADDQoL)量表评估患者的HRQOL状况, 比较应用传统线性回归和分位数回归模型分析T2DM住院患者HRQOL影响因素的结果。   结果   T2DM住院患者平均加权影响得分(average weight impact, AWI)为-2.7(-3.6, -1.9), 得分最低的条目是“工作生涯”(AWI, -4(-6, -2)), “吃东西随意性”(AWI, -4(-6, -2))和“喝东西随意性”(AWI, -4(-6, -2))。线性回归结果显示, 年龄18~59岁(β=0.465, P=0.001)、有肾脏(β=-0.375, P=0.012)和循环系统并发症(β=-0.287, 0.036)是T2DM住院患者HRQOL的危险因素。分位数回归进一步发现, 生命质量越好, 年龄对其影响越弱(β₁=0.931, P₁=0.001;β₂=0.699, P₂=0.001;β₃=0.370, P₃=0.012;β₄=0.313, P₄=0.035);农村居民(β₅=-0.421, P₅ < 0.001)、接受胰岛素治疗(β₃=-0.325, P₃=0.024)、眼部(β₁=-0.546, P₁=0.008;β₅=-0.352, P₅=0.008)、肾脏(β₅=-0.358, P₅=0.025)及循环系统并发症(β₁=-0.803, P₁ < 0.001;β₅=-0.302, P₅=0.011)在个别百分位点上对HRQOL有影响。   结论   年龄、城乡居住地、是否接受胰岛素治疗、合并并发症是T2DM住院患者HRQOL的影响因素, 分位数回归模型可以分析在不同百分位点上影响患者生命质量的因素, 为不同HRQOL患者生命质量的提高提供有针对性的合理建议。     

维生素D与早产儿呼吸窘迫综合征的临床分析

目的 分析早产儿血清维生素D[25-(OH)D₃]水平与早产儿呼吸窘迫综合征(RDS)发生的相关性,为早产儿RDS的治疗提供科学依据。方法 选取2018年9月-2019年3月在武汉大学人民医院新生儿科住院的131例RDS早产儿为实验组,29例非RDS早产儿为对照组。收集所有患儿一般临床资料(性别、分娩方式、母孕情况及Apgar 评分等)及血清25-(OH)D₃结果,分析25-(OH)D₃ 水平与RDS发生之间的关系。结果 RDS组25-(OH)D₃水平低于对照组,差异均有统计学意义(t=2.682,P＜0.05),且CPAP时间、吸氧时间、静脉营养天数、住院天数均明显高于对照组,差异均有统计学意义(t=2.969、2.380、2.571、1.999,P＜0.05)。Logistic 回归分析显示:维生素 D 缺乏是早产儿发生RDS 的危险因素(OR=0.050,95%CI:0.013~0.186,P＜0.05)。结论 早产儿更易发生维生素D缺乏,且维生素D缺乏可能是早产儿RDS发生的危险因素,预防维生素D缺乏有重大意义。     

广东凉茶提取物对兔红细胞膜氧化损伤保护作用研究

目的 从膜成分、结构和功能角度观察广东凉茶提取物对兔红细胞膜氧化损伤的保护作用。方法 实验设对照组、H₂O₂组（1 000 μmol/L）、0.1 mg组（0.1 mg/mL凉茶+H₂O₂）、0.2 mg组（0.2 mg/mL凉茶+H₂O₂）、0.4 mg组（0.4 mg/mL凉茶+H₂O₂）,参照Dodge法制备兔红细胞膜,观察各组对丙二醛（MDA）含量、蛋白羰基含量、膜封闭能力、细胞膜ATP酶活力、谷胱甘肽过氧化物酶（GPX）活力、过氧化氢酶（CAT）活力和细胞膜蛋白成分的影响。结果 与对照组相比,H₂O₂组蛋白羰基含量、GPX酶活力升高,细胞膜封闭率、CAT酶活力、Ca²⁺Mg²⁺-ATP、Mg²⁺-ATP、Na⁺K⁺-ATP酶活力降低（均P<0.01）。与H₂O₂组比,广东凉茶提取物0.1 mg组、0.2 mg组、0.4 mg组的MDA和DNPH含量均降低,细胞膜封闭率、Ca²⁺Mg²⁺-ATP、Mg²⁺-ATP、Na⁺K⁺-ATP酶活力、GPX酶活力、CAT酶活力升高,差异均有统计学意义（均P<0.05）。结论 广东凉茶提取物可抑制H₂O₂引起的红细胞膜成分、结构和功能的损伤作用。     

儿童反复上呼吸道感染与血浆抗菌肽LL-37及维生素D水平的相关性研究

目的 分析人血浆抗菌肽LL-37、25羟维生素D₃与儿童反复上呼吸道感染的相关性,以期为儿童反复上呼吸道感染的防治提供依据。方法 2018年2－8月选取在河北大学附属医院就诊的24例反复上呼吸道感染患儿为实验组,对照组为24例同期健康儿童。两组对象均空腹采血,检测血浆LL-37、25羟维生素D₃含量,同时记录反复呼吸道感染患儿既往1年内发生上呼吸道感染的次数。结果 实验组患儿血浆25羟维生素D₃含量(18.37±5.50) ng/ml与血浆抗菌肽LL-37水平(3.45±0.98) ng/ml明显低于健康对照组(29.24±9.04) ng/ml、(8.93±2.23) ng/ml(P＜0.05)。实验组患儿血浆25羟维生素D₃含量、LL-37水平均与上呼吸道感染次数呈负相关(r=-0.645、-0.560,P＜0.05);血浆25羟维生素D₃含量与血浆LL-37水平呈正相关(r=0.908,P＜0.05)。结论 维生素D缺乏与反复上呼吸道感染发生有关,反复上呼吸道感染患儿血浆LL-37水平下降,且25羟维生素D₃缺乏可能是反复上呼吸道感染患儿血浆LL-37水平下降的重要原因。     

1α,25-二羟维生素D_3对大鼠成骨细胞骨架、间隙连接通讯及[Ca~(2+)]_i的影响

目的研究不同浓度1α,25-二羟维生素D3[1,25-(OH)2·D3]0、10-9、10-8、10-7mol/L对体外培养3～4d龄SD大鼠成骨细胞(OB)骨架F-actin、间隙连接通讯(GJIC)及细胞内钙离子浓度([Ca2+]i)的影响。方法1,25-(OH)2·D3作用20min、24h后测定[Ca2+]i;作用24、48h后观察F-actin及GJIC。结果20min时,不同浓度1,25-(OH)2·D3组[Ca2+]i均显著高于对照组;24h时10-9mol/L组[Ca2+]i则显著低于对照组,其余各组间差异不显著。此时10-8、10-7mol/L组大部分细胞变得扁平,F-actin排列较对照组有序,形成应力纤维;48h时,对照组及10-9mol/L组F-actin表达减少,10-9mol/L组GJIC非常显著地弱于对照组,而10-8、10-7mol/L组大部分细胞F-actin表达完好,GJIC均非常显著地强于其余两组。结论高浓度1,25-(OH)2·D3能够维持OB形态,增强OB间通讯,而低浓度1,25-(OH)2·D3抑制细胞间通讯。     

血清25-(OH)D3水平与儿童社区获得性肺炎严重程度及免疫功能相关性研究

目的 分析不同严重程度肺炎的患儿25-羟维生素D₃[25-(OH)D₃]、体液免疫及细胞免疫水平,研究血清25-(OH)D₃水平与儿童社区获得性肺炎(CAP)严重程度及免疫功能的相关性。方法 收集2016年3月-2017年3月在首都儿科研究所附属儿童医院收治的175例CAP患儿作为病例组,根据病情严重程度分为重症肺炎组(n=87),轻症肺炎组(n=88)。同期采用随机数字法收集在本院保健科进行健康体检的100例健康儿童作为对照组。测定3组儿童的血清25-(OH)D₃水平,同时检测所有肺炎组患儿白细胞计数、中性粒细胞及淋巴细胞比例、血浆C反应蛋白(CRP)、降钙素原(PCT)、体液免疫(IgA、IgG、IgM),细胞免疫(CD4、CD8、CD19、CD16/56)水平,并分析血清25-(OH)D₃水平与炎性细胞及免疫功能之间的相关性。结果 重症肺炎组、轻症肺炎组和对照组血清25-(OH)D₃水平差异有统计学意义(F＝76.95,P<0.05),轻、重症肺炎组间白细胞计数、CRP、PCT、IgG比较差异有统计学意义(P均<0.05)。Pearson相关分析结果显示血清25-(OH)D₃水平与白细胞总数呈负相关(r=-0.307,P<0.05)。多因素Logistic回归分析显示,25-(OH)D₃和IgG水平是儿童重症社区获得性肺炎的高危因素。结论 血清25-(OH)D₃与IgG水平与儿童社区获得性肺炎病情严重程度关系密切,重症肺炎患儿血清25-(OH)D₃与IgG水平明显低于轻症肺炎组,检测患儿的血清25-(OH)D₃和IgG水平对于疾病的早期评估有重要的意义。