Chromosomal Rearrangement Features of Yersinia pestis Strains from Natural Plague Foci in China

The Yersinia pestis chromosome contains a large variety and number of insert sequences that have resulted in frequent chromosome rearrangement events. To identify the chromosomal rearrangement features of Y. pestis strains from five typical plague foci in China and study spontaneous DNA rearrangements potentially stabilized in certain lineages of Y. pestis genomes, we examined the linking mode of locally collinear blocks (LCBs) in 30 Y. pestis strains by a polymerase chain reaction-based method. Our results suggest most strains have relatively stable chromosomal arrangement patterns, and these rearrangement characteristics also have a very close relationship with the geographical origin. In addition, some LCB linking modes are only present in specific strains. We conclude Y. pestis chromosome rearrangement patterns may reflect the genetic features of specific geographical areas and can be applied to distinguish Y. pestis isolates; furthermore, most of the rearrangement events are stable in certain lineages of Y. pestis genomes.     

Dichotomous role of pancreatic HUWE1/MULE/ARF-BP1 in modulating beta cell apoptosis in mice under physiological and genotoxic conditions

Aims/hypothesis

Diabetes mellitus represents a significant burden on the health of the global population. Both type 1 and type 2 diabetes share a common feature of a reduction in functional beta cell mass. A newly discovered ubiquitination molecule HECT, UBA and WWE domain containing 1, E3 ubiquitin protein ligase (HUWE1 [also known as MULE or ARF-BP1]) is a critical regulator of p53-dependent apoptosis. However, its role in islet homeostasis is not entirely clear.

Methods

We generated mice with pancreas-specific deletion of Huwe1 using a Cre-loxP recombination system driven by the Pdx1 promoter (Pdx1cre ⁺ Huwe1 ^fl/fl) to assess the in vivo role of HUWE1 in the pancreas.

Results

Targeted deletion of Huwe1 in the pancreas preferentially activated p53-mediated beta cell apoptosis, leading to reduced beta cell mass and diminished insulin exocytosis. These defects were aggravated by ageing, with progressive further decline in insulin secretion and glucose homeostasis in older mice. Intriguingly, Huwe1 deletion provided protection against genotoxicity, such that Pdx1cre ⁺ Huwe1 ^fl/fl mice were resistant to multiple-low-dose-streptozotocin-induced beta cell apoptosis and diabetes.

Conclusion/interpretation

HUWE1 expression in the pancreas is essential in determining beta cell mass. Furthermore, HUWE1 demonstrated divergent roles in regulating beta cell apoptosis depending on physiological or genotoxic conditions.     

塑料薄膜氧气透过量测定能力验证研究

目的：组织实施塑料薄膜氧气透过量测定能力验证项目,评价检验机构对氧气透过量的检测能力。方法：制备单一水平样品,采用单因素方差分析对样品均匀性进行检验。对能力验证结果进行统计分析,以z比分数评价实验室检测能力。结果：样品均匀性符合要求,满足能力验证计划要求。38家实验室参加塑料薄膜氧气透过量能力验证项目,满意数为34家,满意率为89.5%。结论：多数实验室检测结果满意,部分实验室检测能力有待提高。     

Polymorphism analysis of Glutathione S-transferase A1 in patients with hematological diseases and its effect on GST enzyme activity

Glutathione S-transferases (GSTs) are important drug-metabolizing enzymes that catalyze the binding of glutathione (GSH) to electrophilic substances. GST has genetic polymorphism, and the enzyme activity of GST affects the metabolism of certain drugs in vivo. In the present day, we investigated the GST enzyme activity and GSTA1 gene polymorphism in 170 patients with hematological diseases and explored their relationship. The GSTA1 gene polymorphism of the patient was analyzed by PCR- restriction fragment length polymorphism (PCR-RFLP) technique, and the base sequences of the four mutation sites (-631, -567, -69, and -52) in the promoter region were determined by DNA-Sequencer. The patient's GST enzyme activity was calculated by measuring the rate at which it catalyzed the reaction between 1-chloro-2,4-dinitrobenzene (CDNB) and GSH. The average GST enzyme activities of males and females were 5.20±0.13 and 5.17±0.12 nmol/min/mL, respectively, and the difference was not significant (P = 0.91). The frequencies of genotypes GSTA1*A*A (wild genotype), GSTA1*A*B (heterozygous genotype), and GSTA1*B*B (homozygous mutant genotype) were 75.3%, 22.9%, and 1.8%, respectively. Alleles GSTA1*A and *B were distributed at 86.8% and 13.2%, respectively. The genotype frequency distribution between males and females was no significant difference by Pearson’s chi-square test (P = 0.743). The average GST activity of the heterozygous mutant genotype (4.83±0.76 nmol/min/mL) was lower than the wild genotype (5.34±1.26 nmol/min/mL, P = 0.018), and higher than that of the homozygous mutant genotype (3.32±0.07 nmol/min/mL, P = 0.022). These findings might help us improve the individualized treatment of patients with hematological diseases in the future and promote the development of precision medicine for blood diseases.     

2019 Chinese Hypertension League guidelines on home blood pressure monitoring

In China, automated blood pressure monitors have been readily available for home use. Home blood pressure monitoring has been indispensable in the management of hypertension. There is therefore a need to establish guidelines for home blood pressure monitoring on the basis of the 2012 consensus document. In this guidelines document, the committee put forward recommendations on the selection and calibration of blood pressure measuring devices, the frequency (times) and duration (days) of blood pressure measurement, and the diagnostic threshold of home blood pressure.     

Isthmin 对博来霉素诱导肺纤维化小鼠胶原沉积及血管生成的影响

目的探讨Isthmin（ISM）对肺纤维模型小鼠肺部胶原沉积、血管新生的影响,为肺纤维化的防治提供理论依据。方法将昆明小鼠随机分成：对照组、模型组、ISM组3组,每组16只。博来霉素（BLM）气管内滴人制作小鼠肺纤维化模型,对照组（气管内注射0．9％NS＋尾静脉注入0．9％NS）、模型组（气管内注射BLM＋尾静脉注入0．9％NS）、ISM组（气管内注射BLM＋尾静脉注入Isthmin蛋白）。分别于第7天、14天、21天、28天取实验小鼠肺组织,病理切片苏木精-伊红染色（HE）染色观察肺结构变化,Masson染色了解肺部胶原沉积情况,CD31免疫组化观察对血管内皮细胞数目的影响。结果给予ISM蛋白可减轻小鼠肺结构破坏,减少肺部胶原沉积,血管内皮细胞数目增加。肺组织胶原纤维Masson染色经平均光密度比较,模型组与对照组第7、14、21和28天差异具有统计学意义（P〈0．01）;Isthmin组与模型组比较,第21天和28天差异具有统计学意义（P〈0．01）;肺组织CD31蛋白平均光密度比较,模型组与对照组第14天、21天和28天差异显著（P〈0．05）、第7天差异具有统计学意义（P〈0．01）,Isthmin组与模型组比较,第21天和28天差异具有统计学意义（P〈0．05）。结论ISM蛋白可减轻肺纤维化程度,但不是通过抑制血管形成实现的。     

IL-35与炎症性疾病

IL-35是一种抑制性细胞因子,属于IL-12细胞因子家族的新成员,它是由调节性T细胞结构性分泌产生,由P35和EBI3两个亚基组成.研究发现,IL-35在自身免疫性疾病、炎症性疾病、肿瘤等治疗中有重要作用.在临床上,感染性疾病的控制一直是个难题,IL-35的应用也许为临床提供一种新的思路和方法.