Vitamin D and Diseases of Mineral Homeostasis: A Cyp24a1 R396W Humanized Preclinical Model of Infantile Hypercalcemia Type 1

Infantile hypercalcemia type 1 (HCINF1), previously known as idiopathic infantile hypercalcemia, is caused by mutations in the 25-hydroxyvitamin D 24-hydroxylase gene, CYP24A1. The R396W loss-of-function mutation in CYP24A1 is the second most frequent mutated allele observed in affected HCINF1 patients. We have introduced the site-specific R396W mutation within the murine Cyp24a1 gene in knock-in mice to generate a humanized model of HCINF1. On the C57Bl6 inbred background, homozygous mutant mice exhibited high perinatal lethality with 17% survival past weaning. This was corrected by crossbreeding to the CD1 outbred background. Mutant animals had hypercalcemia in the first week of life, developed nephrolithiasis, and had a very high 25(OH)D₃ to 24,25(OH)₂D₃ ratio which is a diagnostic hallmark of the HCINF1 condition. Expression of the mutant Cyp24a1 allele was highly elevated while Cyp27b1 expression was abrogated. Impaired bone fracture healing was detected in CD1-R396^w/w mutant animals. The augmented lethality of the C57Bl6-R396W strain suggests an influence of distinct genetic backgrounds. Our data point to the utility of unique knock-in mice to probe the physiological ramifications of CYP24A1 variants in isolation from other biological and environmental factors.     

158例非小细胞肺癌中3p25杂合性丢失研究

目的　探讨非小细胞肺癌组织 (NSCLC)中 3p2 5位点上等位基因的杂合性丢失 (LOH)与肺癌发生、发展的相关性。方法　采用银染聚合酶链反应结合二核苷酸 (CA)n重复程序出现多态性评价LOH ,分析 1 58例NSCLC癌组织中 3p2 5等位基因的LOH。结果　 1 58例NSCLC组织中 80例出现 3p2 5LOH ,总的杂合性丢失率为 50 .6%。腺癌组织中 3p2 5杂合性丢失率为 62 .0 % ,鳞癌为 43 .2 % ,两者间差异有显著性 (P <0 .0 5)。 3p2 5LOH与NSCLC临床分期关系不明显 ,Ⅰ、Ⅱ及Ⅲ期分别为 52 .2 %、45.0 %及 52 .8% ,4例良性肺肿瘤和 5例正常胎儿肺组织均未出现 3p2 5LOH。结论　本研究结果表明 3p2 5LOH在NSCLC中普遍存在 ,从而说明 3p2 5位点处可能存在着某些与肺癌发生、发展有关的抑癌基因     

严重创伤患者早期外周血淋巴细胞变化与预后之间的关系

目的探讨严重创伤早期外周血淋巴细胞变化趋势与预后间的关系。方法选取2017年6月至2020年6月北京大学人民医院创伤救治中心收治的严重多发伤患者作为研究对象进行回顾性研究, 观察入院后连续5 d血常规中淋巴细胞变化趋势并进行分组, 第1组: 淋巴细胞减少后在5 d内恢复正常; 第2组: 淋巴细胞减少后未恢复正常; 第3组: 淋巴细胞一直处于正常水平, 并记录各组患者在住院28 d后的转归情况。对收集的临床资料进行统计学分析, 了解创伤早期淋巴细胞变化趋势与预后间的关系。同时, 为排除年龄的影响, 依据年龄是否≥65岁进行分层, 并根据住院时间是否≥28 d分为住院时间延长组和住院时间非延长组, 在不同年龄组中分别探讨淋巴细胞变化与住院时间的关系。结果共纳入患者83例, 其中男性66例, 女性17例, 主要受伤机制为车祸伤和高处坠落伤, 创伤严重程度评分(injury severe score, ISS)为(30±11)分。根据连续5 d淋巴细胞变化趋势分组, 第1组32例, 第2组33例, 第3组18例。第2组33例患者中, 在住院28 d内死亡5例, 死亡率为15.2%(5/33), 未出院9例, 均高于其他两组(P < 0.05)。进一步按年龄进行分层后, 发现在高年龄患者中淋巴细胞处于低水平是住院时间≥28 d的危险因素, 但在低年龄患者中, 发现中性粒细胞持续偏高与预后不良相关。结论严重创伤后外周血淋巴细胞一直处于低水平与预后不佳密切相关, 尤其在高年龄患者中明显, 淋巴细胞可作为一项可靠指标用于预后评估。     

Vitamin D Metabolite Ratio in Pregnant Women with Low Blood Vitamin D Concentrations Is Associated with Neonatal Anthropometric Data

Existing evidence on the correlation between maternal vitamin D concentrations and birth outcomes is conflicting. Investigation of these associations requires accurate assessment of vitamin D status, especially in individuals with low 25-hydroxyvitamin D (25(OH)D) concentrations. This study examined the correlations between birth outcomes and the maternal vitamin D metabolite ratio (VMR) 1 (defined as the ratio of 24,25(OH)₂D₃ to 25(OH)D) and VMR2 (defined as the ratio of 3-epi-25(OH)D₃ to 25(OH)D) using data from the Japan Environment and Children’s Study at Chiba Regional Center. A total of 297 mother–neonate pairs were analyzed. Using liquid chromatography–tandem mass spectrometry, we measured 25(OH)D₂, 25(OH)D₃, 24,25(OH)₂D₃, and 3-epi-25(OH)D₃ concentrations in maternal serum samples. These data were analyzed in relation to birth anthropometric data using multivariable linear regression. Of the study participants, 85.2% showed insufficient vitamin D concentrations. VMR1 was strongly correlated with 25(OH)D concentrations, whereas VMR2 showed a weak correlation. Only VMR2 was associated with all anthropometric data. VMR2 in pregnant women with low vitamin D blood concentrations is a useful marker for neonatal anthropometric data and is independent of 25(OH)D. Accurate measurement of vitamin D metabolites could help better understand the effects of vitamin D on birth outcomes.     

Correlation between Serum 25-Hydroxyvitamin D Level and Peripheral Arterial Stiffness in Chronic Kidney Disease Stage 3–5 Patients

Vitamin D deficiency and high brachial-ankle pulse wave velocity (baPWV) are each independently associated with higher incidence of mortality and cardiovascular (CV) disease or CV events, respectively. This study aimed to evaluate the relationship between serum 25-hydroxyvitamin D levels and baPWV in non-dialysis patients with stage 3–5 chronic kidney disease (CKD). We enrolled 180 CKD patients. A commercial enzyme-linked immunosorbent assay was used to measure 25-hydroxyvitamin D levels. BaPWV values were measured using an automatic pulse wave analyzer. Either left or right baPWV > 18.0 m/s was considered indicative of peripheral arterial stiffness (PAS). In this study, 73 (40.6%) patients were found to have PAS. Compared to those without PAS (control group), patients with PAS were older and had higher incidence of diabetes mellitus, higher systolic and diastolic blood pressure, higher levels of intact parathyroid hormone, and C-reactive protein, and lower levels of 25-hydroxyvitamin D. Multivariate logistic regression analysis found 25-hydroxyvitamin D levels (odds ratio [OR]: 0.895, 95% confidence interval [CI] 0.828–0.968, p = 0.005) and old age (OR: 1.140, 95% CI 1.088–1.194, p < 0.001) to be independently associated with PAS in patients with stage 3–5 CKD. Lower serum 25-hydroxyvitamin D levels and older age were associated with PAS in these patients.     

脐血和新生儿外周血CD4+CD25+调节性T细胞的表型特征及意义

目的 探讨脐血和新生儿外周血中CD4 CD25 调节性T细胞的表型特征及其意义.方法以18份脐血和9份新生儿外周血为标本,细胞膜表面抗原采用单抗直接标记法,检测胞内抗原(CD152、FoxP3)时先标记膜表面抗原,固定破膜后再标记胞内抗原,应用多参数流式细胞仪进行检测和结果分析.结果脐血和新生儿外周血中的CD4 CD25 T细胞显示为独立的细胞群,脐血中该群细胞占CD4 T细胞比例为(9.26±2.43)%,新生儿外周血中的比例则为(9.35±2.30)%;在表型方面,大部分是CD45RA 的细胞,同时表达CD62L、胞浆内的CD152,也表达FoxP3,CD4 CD25 FoxP3 占CD4 T细胞比例为(1.92±0.28)%.结论 脐血和新生儿外周血中存在着一群单纯且水平较高的CD4 CD25 调节性T细胞,它们可能在发挥对母体非遗传性抗原的耐受及防止母体对胎儿的排斥反应中具有独特的作用.     

脓毒症患者调节性T细胞与CD64指数的相关性研究

目的 探讨CD4+ CD25+/highCD127low/-、CD14+ HLA-DR+在脓毒症发生发展中的作用.方法 流式细胞术检测脓毒症患者(其中生存组17例,死亡组11例)CD4+ CD25+/highCD127low/-、CD14+ HLA-DR+、CD64指数,同时测定白细胞数(WBC)和C-反应蛋白(CRP)的水平,并与正常对照组比较.结果 脓毒症组CD4+ CD25+/highCD127 low/-、CD64指数均明显高于正常对照组,CD14+ HLA-DR+明显低于正常对照组;动态观察结果显示,随着疾病的进展,生存组CD4+ CD25+highCD127low/-、CD64指数均明显回落,而死亡组两者却持续升高;而CD14+ HLA-DR+刚好相反,生存组CD14+HLA-DR+逐渐升高,死亡组CD14+ HLA-DR+明显低于存活组,且持续处于低水平状态;相关性分析显示,CD4+ CD25+/high CD127low/-与CD64指数、CRP正相关;CD14+ HLA-DR+与CD64指数、CRP明显负相关;CD54指数与WBC、CRP正相关.结论 CD4+CD25+/highCD127low/-、CD14+ HLA-DR+与疾病感染和炎症严重程度密切相关,可作为疾病严重程度及预后的指标.     

腹膜透析相关腹膜炎患者治疗失败预测模型的构建和验证：一项多中心临床研究

目的构建和验证腹膜透析相关性腹膜炎（PDAP）患者治疗失败的风险预测模型。方法对2013年1月1日~2019年12月31日在吉林省3个腹膜透析中心发生PDAP的腹膜透析（PD）患者进行了回顾性分析。收集入选者基线临床资料，主要研究终点为治疗失败。根据腹膜透析中心地域的不同，将数据分为训练集（吉林大学第二医院、吉林大学第一医院二部）和验证集（吉林市中心医院）。采用Logistic风险回归模型筛选影响PDAP治疗失败的危险因素，用Stata建立预测模型；用ROC曲线和校准曲线评估模型的区分度和准确性，并以DCA曲线评估列线图的临床有效性。结果共纳入977例次PDAP，训练集中625例次，其中78例治疗失败，验证集中352例次，其中35例治疗失败。建模队列多因素Logistic回归分析结果显示，血清白蛋白、第5天腹透液白细胞计数、透析龄和致病微生物类型是治疗失败的独立危险因素，在训练集中的C统计量为0.827（95% CI：0.784–0.871）。在验证集中，C统计量为0.825（95%CI：0.743-0.908）。预测模型在训练和验证集的校准方面都表现良好。结论基于血清白蛋白、第5天腹透液白细胞计数、透析龄和致病微生物类型构建了预测模型，性能良好。