Objective:To construct an estimating equation to accurately reflect the aging phenomenon of the glomerular filtration rate(GFR).Methods:Healthy subjects receiving physical examinations at the First Affiliated Hospital of Nanjing Medical University between January 2017 and April 2018 were included in the study, and the aging phenomenon of renal function indicators such as serum creatinine(Scr)was used as the reference standard to evaluate the accuracy of four Scr-based GFR equations during GFR aging, including the full age spectrum(FAS)equation, the Chronic Kidney Disease Epidemiology Collaboration(CKD-EPI)equation, the Osaka equation and the Xiangya equation.Results:Of 37 636 individuals receiving physical examinations, 6 534 met the criteria specified in this study.Scr, serum urea nitrogen, serum uric acid, and serum albumin showed a significant aging phenomenon( H=191.640, 196.693, 83.271, 414.585, P<0.001 for all).The GFR estimated by the four equations all decreased with aging, but the starting point and rate of decline were significantly different.The GFR aging phenomenon estimated by the FAS equation was closer to the trend of renal function indicators. Conclusions:The FAS equation may be more applicable to healthy people to understand the aging phenomenon of GFR.

The modern bio-fermentation industry requires design and creation of efficient microbial cell factories for directed conversion of raw materials to target products. The main criteria for assessing the performance of microbial cell factories are their product synthesis capacity and stability. Due to the deficiencies of plasmids in gene expression such as instability and being easy to lose, integration of genes into chromosome is often a better choice for stable expression in microbial hosts. To this end, chromosomal gene integration technology has received much attention and has developed rapidly. In this review, we summarize the recent research progresses of chromosomal integration of large DNA fragments in microorganisms, illustrate the principles and features of various technologies, highlight the opportunity brought by the CRISPR-associated transposon systems, and prospect future research direction of this technology.
Chromosomes ; Plasmids ; DNA ; Cloning, Molecular ; Fermentation

Objective:To explore the phenotype and molecular genetic features of spinocerebellar ataxia type 2 (SCA2) cases with ATXN2 intermediate-length CAG-repeat expansion.Methods:Fragment analysis by capillary electrophoresis was performed to detect the dynamic mutations in the samples of the probands in 1 383 pedigrees with autosomal dominant inherited ataxia in Research Center for Motor Disorders and Neurogenetic Diseases, Department of Neurology, China-Japan Friendship Hospital from 2005 to 2018. The clinical and genetic features of individuals carrying the ATXN2 intermediate-length CAG-repeat expansion were carefully analyzed.Results:Two hundred and three individuals (including the probands and members of their families) in 163 families carried the expanded CAG repeats in ATXN2 gene, among which 107 individuals in 93 families carried the intermediate-length CAG-repeats. Within 20 parent-child pairs, the CAG repeats increased 0-28 copies in 16 pairs with paternal inheritance, and 0-4 copies in 4 pairs with maternal inheritance.Conclusions:For suspected SCA2 cases, ATXN2 gene testing should be performed on the parental members and adult offspring members in the family. Dynamic mutations testing is essential to identify the individuals with ATXN2 intermediate-length repeat expansion, which is very important for genetic counseling.

Rare diseases have been a major challenge for clinical medicine and public health challenge in China. One of the effective measures is to conduct proactive research on rare diseases to deal with the disease burden of the diseases. However, low prevalence, disperse distribution of patients, lack of knowledge about the disease course, and phenotype heterogeneity hamper the development of research for rare diseases. Recently, it has been found that patients registry is effective in understanding the course of the disease and accu- mulating the cases and data of clinical research or clinical trial design. At present, most of developed countries or regions in the world have promoted clinical research and clinical trials of new medications on rare diseases by using the registration of rare disease. In 2016, Peking Union Medical College Hospital established China's first registry system at the national level-National Rare Disease Registry System of China(NRDRS). NRDRS has accumulated 68 137 cases data registered by the researchers from China's 101 collaborating hospitals in 29 provinces/municipalities/autonomous regions, covering 171 different, and forming 188 cohorts. To date, NRDRS complete the initial stage of resources buildup.Nex stage will be focused on clinical research and clinical trials related to rare diseases based on NRDRS. This article is on the process of building NRDRS, the potential support for conducting clinical research and clinical trials related to rare diseases, and the challenges will be faced.

Objective:To investigate the prevalences of overweight and obesity and its relationship with the risk factors of cardiovascular diseases among physical examination population in Nanjing Drum Tower Hospital.Methods:A retrospective analysis was performed on 384 061 adults aged 20 years and older. Age- and sex-standardized prevalences of overweight and obesity were calculated using Chinese census data in 2010. Multivariate logistic regression analysis was used to assess the associations of overweight and obesity with the risk factors of cardiovascular diseases.Results:The age-standardized prevalences of overweight and obesity were 42.8% and 13.2% in men and 23.9% and 6.6% in women. A gradually increasing trend was observed in the prevalences of overweight and obesity from 2008 to 2016, especially in subjects aged 20-39 years. Overweight and obesity were significantly associated with increased risks of dyslipidemia, diabetes mellitus, hypertension, and hyperuricemia. These associations were found to be the strongest among subjects aged 20-39 years, which became weaker along with the increasing of age. The OR(95% CI) of dyslipidemia, diabetes mellitus, hypertension, and hyperuricemia were 4.23(4.01-4.47), 3.70(2.97-4.60), 6.19(5.76-6.64), and 3.66(3.45-3.88) in obese men aged 20-39 years, while 5.29(4.63-6.04), 6.38(3.86-10.55), 9.36(7.86-11.13), and 6.65(5.70-7.74) in obese women aged 20-39 years, respectively. Conclusion:The increasing trend in the prevalence of overweight and obesity is a risk factor for cardiovascular diseases in Nanjing adults, especially in individuals aged 20-39 years.

Pre-testing preparation is the basis and starting point of genetic testing.The process includes collection of clinical information,formulation of testing scheme,genetic counseling before testing,and completion of informed consent and testing authorization.To effectively identify genetic diseases in clinics can greatly improve the diagnostic rate of next generation sequencing (NGS),thereby reducing medical cost and improving clinical efficacy.The analysis of NGS results relies,to a large extent,on the understanding of genotype-phenotype correlations,therefore it is particularly important to collect and evaluate clinical phenotypes and describe them in uniform standard terms.Different types of genetic diseases or mutations may require specific testing techniques,which can yield twice the result with half the effort.Pre-testing genetic counseling can help patients and their families to understand the significance of relevant genetic testing,formulate individualized testing strategies,and lay a foundation for follow-up.

With high accuracy and precision,next generation sequencing (NGS) has provided a powerful tool for clinical testing of genetic diseases.To follow a standardized experimental procedure is the prerequisite to obtain stable,reliable,and effective NGS data for the assistance of diagnosis and/or screening of genetic diseases.At a conference of genetic testing industry held in Shanghai,May 2019,physicians engaged in the diagnosis and treatment of genetic diseases,experts engaged in clinical laboratory testing of genetic diseases and experts from third-party genetic testing companies have fully discussed the standardization of NGS procedures for the testing of genetic diseases.Experts from different backgrounds have provided opinions for the operation and implementation of NGS testing procedures including sample collection,reception,preservation,library construction,sequencing and data quality control.Based on the discussion,a consensus on the standardization of the testing procedures in NGS laboratories is developed with the aim to standardize NGS testing and accelerate implementation of NGS in clinical settings across China.

Bioinformatic analysis and variant classification are the key components of high-throughput sequencing-based genetic diagnostic approach.This consensus is part of the effort to develop a standardized process for next generation sequencing (NGS)-based test for germline mutations underlying Mendelian disorders in China.The flow-chart,common software,key parameters of bioinformatics pipeline for data processing,annotation,storage and variant classification are reviewed,which is aimed to help improving and maintaining a high-quality process and obtaining consistent outcomes for NGS-based molecular diagnosis.

Clinical genetic testing results are compiled into a standardized report by genetic specialists and provided to clinicians and patients (Should the patient be intellectually disabled or under 18,the report will be provided to his/her parents or legal guardians).The content of genetic testing report should conform to relevant guidelines,industry standards and consensus.The decisions of clinicians will be made based on the report and clinical indications.Genetic counselors should provide post-test counseling to clinicians and patients or their authorized family members.A mechanism of follow-up visit after the genetic testing should be established with informed consent.Data should be shared by clinical institutions and genome sequencing institutions.As findings upon follow-up visit can help with further evaluation of the results,genome sequencing institutions should regularly re-analyze historical and follow-up data,and the updated results should be shared with clinical institutions.All activities involving reporting,genetic counselling,follow-up visiting,and re-analyzing should follow the relevant guidelines and regulations.

The use of microbial cell factories to achieve efficient conversion of raw materials and synthesis of target substances is one of the important research directions of synthetic biology. Traditional industrial microorganisms have mainly used sugar-based raw materials as fermentation substrates. How to adopt cheaper carbon resources and realize their efficient use has been widely concerned. Formic acid is an important organic one-carbon source and widely used in industrial manufacturing of pesticides, leather, dyes, medicine and rubber. In recent years, due to the demand fluctuation in downstream industries, formic acid production is facing the dilemma of overcapacity, and therefore, requiring new conversion paths for expansion and extension of the related industrial chain. Biological route is one of the important options. However, natural formate-utilizing microorganisms generally grow slowly when metabolizing formic acid, and moreover, are difficult to be artificially modified by the absence of effective genetic tools. Construction of non-natural formate-utilizing microorganisms is another alternative strategy, but still in its infancy and has a huge space for further improvements. Here, we briefly summarize the recent research progress of biological utilization of formic acid, and also propose the future research focus and direction.
Fermentation ; Formates ; metabolism ; Industrial Microbiology ; trends ; Synthetic Biology ; trends