Changing epidemiology of chronic kidney disease as a result of type 2 diabetes mellitus from 1990 to 2017: Estimates from Global Burden of Disease 2017

Aims/IntroductionType 2 diabetes mellitus has been a leading cause of chronic kidney disease (CKD), with a heterogeneous distribution worldwide. Optimal healthcare planning requires an understanding of how the burden of CKD as a result of type 2 diabetes mellitus has changed over time and geographic location, as well as the potential roles of sociodemographic, clinical and behavioral factors in these changes.Materials and MethodsWe used the Global Burden of Disease data from 1990 to 2017 at the global, regional and national levels to investigate changes in the incidence, death and disability‐adjusted life years of CKD as a result of type 2 diabetes mellitus, incorporating both epidemiological research and risk factor monitoring.ResultsThe incident cases of CKD as a result of type 2 diabetes mellitus worldwide in 2017 had increased by 74% compared with 1990; total disability‐adjusted life years had increased by 113%, mainly attributable to population expansion and demographic transition. The Sociodemographic Index was significantly and negatively correlated with overall CKD as a result of type 2 diabetes mellitus burden. However, in 82 countries and territories, the burden was not alleviated in parallel with socioeconomic development.ConclusionsCKD as a result of type 2 diabetes mellitus has been the main contributor to the increasing burden of CKD over the past several decades. We suggest a more pragmatic approach focusing on early diagnosis, primary care and adequate follow up to reduce mortality and the long‐term burden in low‐to‐middle Sociodemographic Index regions. Interventions should address high systolic blood pressure, as well as overweight and obesity problems, especially in high‐income regions.     

A lipopeptide biosurfactant from Bacillus sp. Lv13 and their combined effects on biodesulfurization of dibenzothiophene

The process of using biodesulfurization (BDS) to remove sulfur compounds in petroleum has limitations such as low efficiency and low mass transfer. Therefore, it is important to study the combined effects of biosurfactant and the strain on BDS. A thermophilic desulfurization strain, Bacillus sp. Lv13, was isolated from the oilfield and used to produce biosurfactant (BS). The strain was identified as Bacillus licheniformis, a moderate thermophilic bacterium. Its BS was identified as lipopeptide using thin-layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-IR). The emulsification efficiency after 24 h (E₂₄) and critical micelle concentration (CMC) were determined to be 46.93% and 30 mg L⁻¹, respectively. The combined effects of biosurfactant and the strain on BDS was confirmed using the Gibbs assay, GC-MS and BaCl₂ test. Results showed that the yield of 2-hydroxybiphenyl (2-HBP) from dibenzothiophene significantly increased after the addition of lipopeptide into the reaction system. This could be illustrated by the stabilization of emulsion, lower CMC value, higher mass transfer rate with the addition of lipopeptide, and the enhancement in the capacity of BDS as well as the catalytic ability of the microbial cell.

Complex interactions among DBT, bacteria and biomolecules play a major role in the absence of lipopeptides. After adding lipopeptides, DBT degrades rapidly to HBP through BDS.     

Comparative study on risk for birth defects among infants after in vitro fertilization and intracytoplasmic sperm injection

This large retrospective study was conducted to compare the risk for birth defects among infants conceived by in vitro fertilization (IVF) with that among infants conceived by intracytoplasmic sperm injection (ICSI) and to explore the effect of frozen embryo transfer (FET) on the risk for birth defects among infants born by IVF and ICSI. All patients who received assisted reproductive technology (ART) treatment and who underwent childbirth during the period January 2005–August 2017 were included in this study. There were 18,221 births after ART included in the analysis; of these births, 12,649 were conceived by IVF, and 5,572 were conceived by ICSI. In the study, the prevalence of any birth defect in singleton infants was 1.15% with the use of IVF and 1.38% with the use of ICSI, and that in twin infants increased to 2.74% by IVF and 2.58% by ICSI. However, no significant difference between IVF and ICSI was found among all infants, singleton births or twin births. Additionally, in assessing ART infants born after FET, we did not detect a difference in the risk for birth defects between infants born by IVF and those born by ICSI. These results indicate that among the entire cohort of children conceived from ART and among the children conceived from FET, the risk for birth defects after ICSI is similar to that after IVF.Abbreviations: IVF: in vitro fertilization; ICSI: intracytoplasmic sperm injection; FET: frozen embryo transfer; ART: assisted reproductive technology; ET: embryo transfer; BMI: body mass index; OHSS: ovarian hyperstimulation syndrome; CMOH: Chinese Ministry of Health; ICD-10: International Classification of Diseases, 10^th edition; PTB: preterm birth; OR: odds ratio; aOR: adjusted odds ratio; CI: confidence interval     

中国成年人代谢异常相关的体质指数和腰围切点研究

目的 研究中国成年人BMI和腰围与各项代谢危险因素之间的相关性,确定超重肥胖的适宜BMI和腰围切点。方法 中国慢性病前瞻性研究于2004-2008年进行基线调查,并于2013-2014年随机抽取了5%的研究对象进行第2次重复调查。本研究剔除体格指标或代谢危险因素变量缺失或极端值、自报患有恶性肿瘤者,基线纳入501 201人,第2次重复调查纳入19 201人。比较不同BMI和腰围下代谢危险因素异常率,通过受试者工作特征（ROC）曲线分析,确定预测高血压、糖尿病、血脂异常和危险因素聚集的适宜BMI和腰围切点。结果 随BMI或腰围的增加,高血压、糖尿病、血脂异常和危险因素聚集患病率均呈现上升的趋势。依据正确指数最大的原则选取BMI超重切点和腰围切点,男性和女性BMI超重切点均接近24.0 kg/m²,男性腰围切点接近85 cm,女性腰围切点约为80~85 cm。男性和女性中,检出各项代谢危险因素特异度达到90%的BMI切点范围为27.0~28.9 kg/m²,多数接近28.0 kg/m²,以28.0 kg/m²作为肥胖切点。结论 本研究在更新开展的大样本调查中进一步验证了中国肥胖问题工作组2002年推荐的超重和肥胖标准,超重和肥胖的BMI切点分别为24.0和28.0 kg/m²;中心性肥胖的腰围适宜切点男性为85 cm,女性为80~85 cm。     

大型人群队列终点事件长期随访技术规范团体标准解读

终点事件长期随访是大型人群队列研究中极为重要和艰巨的工作,是大型队列研究取得成功的关键,而如何规范化地开展大型人群队列终点事件长期随访是工作的基础。中华预防医学会组织浙江省疾病预防控制中心等单位撰写《大型人群队列终点事件长期随访技术规范（T/CPMA 002－2019）》团体标准。标准以“科学性、规范性、适用性和可行性”为原则,提出了大型人群队列在长期随访的目标人群、随访时间、随访内容、随访方法、质量控制和指标评估等方面的原则和具体要求,以指导和规范我国已建立或拟开展的大型人群队列、区域性人群队列以及特殊人群队列,促进国内科研水平的提升,增加国际影响力,最大程度的支持疾病防控的决策与实践。     

2017～2018学年南京市浦口区学校教学环境卫生监测结果分析

目的了解浦口区中小学校教学环境卫生现状,指导学校改善教学卫生状况。方法按照整群分层抽样方法,选取中小学校11所,每所学校按照教室的结构、层次、朝向、采光类型等选取有代表性的6间教室进行监测,监测项目包括教室人均面积、课桌椅、黑板、教室采光、教室照明、教室微小气候等指标。结果在18项监测指标中,合格率高于90%的有7项,由高到低依次为黑板尺寸、窗地面积比、灯桌间距、二氧化碳浓度、噪声、男生蹲位和小便槽;合格率低于60%的指标有8项,由低到高依次为课桌椅符合率、后墙反射比、黑板反射比、小学厕所蹲位宽、黑板面照度、采光系数、课桌面照度和黑板下缘距,其中前三项合格率在10%以下。结论浦口区中小学校教学环境卫生现状不佳,尤其是课桌椅符合率、后墙反射比、黑板反射比合格率低于10%,应引起学校及有关部门的重视,采取有效措施加以改善。     

One step DNA amplification of mammalian cells in picoliter microwell arrays

We developed a strategy for direct DNA amplification of single cells on a PEG-modified silica chip with 30 600 picoliter-sized microwells. HPV-positive cells in heterogeneous populations were successfully detected with high accuracy sensitivity as high as single copy.

One-step PCR of a single cell in a picoliter microwell array was developed and applied to detect a target with the sensitivity of a single copy.

Sensitive and specific detection of nucleic acids from rare but biologically important individual cells can bring in-depth understanding of cell differentiation and disease occurrence; for example, stem cells and circulating tumour cells in cancer patients.^1–4 As the most powerful and basic technologies to analyse nucleic acids, polymerase chain reaction (PCR) produces millions of copies of DNA molecules starting from a single template DNA. In PCR of cell populations, cell lysis and specific enrichment procedures need to be highly efficient and compatible with downstream analysis, which may lose rare DNA and cannot reveal cell heterogeneity. Methods for isolating and PCR of single cells are essential to obtain more meaningful information.Several research groups have reported techniques for gene analysis using a small amount of cells, even a single cell.^5–9 Flow cytometry may be the most effective way for isolating large numbers of individual cells, but gene analysis of these sorted cells is still conducted in vials, with microliter volumes and low throughput. Analytical tools and methods for high throughput gene analysis based on microfluidic technology have emerged in recent years,^10,11 including micro wells and micro droplets. Fusion and division of droplets are needed to add reagent and reduce lysate-induced inhibition effects, but they destroy the integrity of DNA¹² and the accuracy of detection. Meanwhile, sample transfers between generation and operation of droplets, DNA amplification, and fluorescent detection also induces high risk of sample loss. Last but not least, complicated fabrication and operation processes, as well as high commercial costs of these microfluidic chips, are not affordable by most biological labs. One-step PCR of cells in micro wells without sample transfer is an effective and low cost method to ensure the integrity of cell DNA. However, due to lysate-mediated inhibition, reducing reaction volume to picoliters for high throughput analysis of cells is still a challenge today.In this study, we present a strategy for one-step DNA amplification of a single cell on a PEG-modified silica chip with 30 600 picoliter-sized microwells. We applied this strategy to detect HPV 16 E6 positive cells with existence of negative cells as background, demonstrating its feasibility for medical diagnosis and related applications. Compared with flow cytometry or microfluidic chips, this strategy can robustly detect a single copy of nucleic acids from single cells within 2.5 hours by an integrated operation. It is dramatically simpler and cheaper than previously reported methods, thus more accessible by most biology labs.The workflow of our approach, shown as Fig. 1, illustrates the size-optimized silica chip is 2.2 × 2.2 cm² and has 30 600 microwells and is 100 μm in diameter, 40 μm in depth, and 314 pL in volume (Fig. 1A).¹³ To avoid air bubbles and protein adsorption during sample loading, surfaces of the chip were modified by methoxy-PEG-silane (2-[methoxy(polyethyleneoxy)propyl]-trimethoxysilane). Our method for fabricating the heating chamber is as follows: we first dried the silica chip and put it on the bottom of a culture dish. A pre-treated cell suspension with optimized density was added to the culture dish and then subjected to centrifugation (Fig. 1B). After cells were loaded into the microwells, the chip was washed with water and dried again. Then, PCR reagent was added on one side of the chip and a piece of silica gel was used to wipe the PCR reagent to another side (Fig. 1C). Next, the chip was sandwiched in a copper-glass chamber, which was filled with mineral oil and fixed by screws (Fig. 1D and S1^†). Finally, this heating chamber was put on top of the heating module of a thermal cycler for PCR assay. TaqMan probes specific to target sequence produce a detectable signal when the positive cell is present and this PCR signal can be detected either during or at the end point of the assay by a fluorescence microscope (Fig. 1E and F).Open in a separate windowFig. 1Working flow of one-step PCR for single cells. (A) Silica chip with microwells. (B) Loading of cells. (C) Division of PCR reagent. (D) Assembled heating chamber. (E) Heating chamber containing target cells generate fluorescent signal during PCR. (F) The fluorescent signal can be detected by a wide-field microscope.As the simplest and most accessible method, centrifugation was used to load cells into microwells. According to single cell trapping analysis that was previously demonstrated, the number of wells containing single cells climbs and then declines with increasing cell density.¹⁴ To obtain the maximum amount of single cells, we optimized density of the cell suspension for loading by increasing cell density gradually in a relatively small range and recording the number of cells in the microwell. The correlation between cell density and cell numbers in microwells is shown as Fig. 2. As expected, both the numbers of wells containing single cells and multi-cells increased with increased loading density, but the percentage of single cells decreased gradually. To balance these two aspects, we chose a loading density between 40 000–60 000 cells per mL. At this constant parameter, we obtained 8000 wells with cells, and more than 80% of these wells contained a single cell.Open in a separate windowFig. 2Cell loading analysis. (A) Chip after loading live cells stained by calcein AM. (B) Bright field and fluorescent images of higher magnification images show the PI labeled cells in a microwell. (C) Relation between the loading density of cell suspension and the cell distribution on a chip. Percentage of single cells among all nonempty wells (red line) decreased with increased cell loading density.We used the same chip for cell loading and PCR reagent division to ensure the integrity of the cell''s nucleic acids. There are several hindrances to fulfilling this strategy. The first one is to reduce the phosphate-buffered saline (PBS) normally used to suspend live cells during cell loading. Although the microwell is picoliter-sized, PBS salt precipitated when drying the chip after cell loading and was resolved during the PCR reagent division. The pretreatment of a cell sample we used was to eliminate PBS from cell suspension through fixing cells by paraformaldehyde (PFA) and re-suspending them in deionized water. Therefore, both PBS and PFA were eliminated. Our fixation process prevented cells from bursting during buffer replacement and also inactivated enzymes that inhibit a PCR reaction. Our results demonstrated that PBS elimination increased the PCR efficiency dramatically (Fig. S2^†). On the other hand, suspending cells in water can keep the surface of a chip clean enough for PCR reagent division. Otherwise, air bubbles will generate when wiping the PCR reagent, become larger, and move during the thermal cycle, bringing strong fluorescent background finally (Fig. S2^†).The lysate-mediated inhibition effect increased dramatically when the reaction volume decreased to picoliter-scale, not only because of the remaining lysis reagent itself, but also due to the high concentration of cell lysate.^15–18 According to reported works that BSA could be a mild reagent for direct cell lysis,^19,20 another effort we made to fulfill this strategy was the introduction of bovine serum albumin (BSA) to PCR reagent. Compared with traditional PCR in a vial, PCR at picoliter scale has higher surface to volume ratio; thus, we needed a high enough concentration of BSA to lysis cells and prevent interface-adsorption of DNA polymerase. Unfortunately, we also found that background noises became stronger as BSA concentration increased. Considering these two contradictory aspects, we finally optimized the BSA concentration at 25 mg mL⁻¹, which is a very high concentration compared with 1 mg mL⁻¹ in traditional PCR carried out in vials and at which background noises are acceptable for detection.Human papilloma virus (HPV) induced cervical cancer was used as a model system to demonstrate the feasibility of this method. It is reported that HPV 16 E6 gene mediates the oncogenic property of HPV and over 99% of all cervical cancers are high-risk HPV-positive.^21,22 The detection of HPV positive cells can be used as a primary diagnosis. We first verified the PCR reagent and PEG-modified chip worked well by cell lysate (Fig. S3A and B^†). Next, we detected the HPV DNA in CaSki cells (HPV+, 600 copies) and human Alu elements (Fig. S4^†), which are the most abundant transposable elements dispersed throughout the human genome.^23,24 For both of these cases, we obtained the same specific PCR signal after 25 cycles (Fig. 3A and S4^†). To exclude false signals, CaSki cells shown in Fig. 3A were not fluorescent labelled. Nevertheless, a cell itself generated a fluorescent signal immediately after the initial denaturation of PCR and this non-specific fluorescence changed very little during the thermal cycle. The only reason may be that cells adsorbed some TaqMan probes that were destroyed during denaturation. On the contrary, we took advantage of this property to identify the cell itself from a PCR signal in the following experiments when the cells were not initially stained.Open in a separate windowFig. 3One-step PCR of single CaSki cells for detecting HPV DNA. (A) Images of the same chip during PCR on cycles 1, 15, and 40. Bright spots in cycle-1 and cycle-15 are nonspecific fluorescence of cells, and the bright wells in cycle 40 are PCR signals. (B) Definition of microwells. Cell+/fluo+ is a microwell with both cell and PCR signals; cell−/fluo+ is a microwell with a PCR signal but without cells; cell+/fluo− is a microwell that contains cells, but no PCR signal; cell−/fluo− is empty background. (C) Fluorescence intensity curve illustrating the normal amplification of cells. (D) Statistical analysis of the accuracy of this strategy. The diameter of a well is 100 μm.We also stained cells by PI before loading them into microwells to distinguish cells from the PCR signals more clearly. We defined the relationship of cell-PCR fluorescence by a higher magnification shown as Fig. 3B and took images after each 5 cycles. The fluorescence of 35 cell+/fluo+ and 35 cell−/fluo− were analyzed. The curve of cell+/fluo+ shows an “S” shape which indicates a normal amplification and also a significant difference from the cell-/fluo- (empty well, Fig. 3C). On the other hand, it is easy to find that all the cell−/fluo+ (false positive signal) are near cell+/fluo+ (Fig. 3B), which indicated the possibility of leakage from a neighboring positive well. As these false positive signals are always together with positive signals, and statistics suggest that the ratio of cell+/fluo− is 1.1% (Fig. 3D), we can conclude that once a positive cell appears, it could be detected with an accuracy as high as 98.9% (sum of cell+/fluo+ and cell−/fluo+).In order to confirm the utility of this assay to identify specific cells in heterogeneous populations, we detected HPV 16 gene in SiHa cells (HPV+) based on TaqMan PCR assays with existence of C-33a cell (HPV−) as background, which were not infected by HPV. Unlike the large number of HPV in CaSki and Alu element in human cells, each SiHa cells contain 1–2 copies of HPV 16 DNA only on average.^25–27 Consistent with what we predicted, HPV-negative cells C-33A showed no PCR signals after 50 thermal cycles (Fig. 4). We found that SiHa cells, but not all of them (23% on average), generated positive PCR signals, which is different from what we originally thought (Fig. 4). We also mixed SiHa cells and C-33A cells to decline the positive cell content and the positive signals decreased continually. These findings demonstrated our strategy successfully detected a single copy of target DNA from single cells among heterogeneous populations.Open in a separate windowFig. 4Detection of HPV 16 E6 in negative cells, positive cells, and heterogeneous populations. No PCR signals were generated in C-33A cell after 50 cycles. Single copy of HPV16 could be detected in both SiHa cells and the cell mixtures.There are several possibilities for the contradiction on HPV 16''s copies in a SiHa cell. First, the reported number of 1–2 copies on average may be too low to detect in the picoliter-sized wells shown in our strategy, especially with a high concentration of protein as background. The second is that not every SiHa cell really has HPV 16 DNA because the reported data is an average number. More data are needed to give a deeper explanation through single cell sequencing or digital PCR of single SiHa cells.     

基于随机森林的男性急性心肌梗死诊断模型建立及验证

目的利用随机森林建立及验证男性急性心肌梗死诊断模型。 方法检测2016年1至6月于武汉大学人民医院心内科住院的205例心绞痛或急性心肌梗死男性患者的血清生化及生物标志物指标,其中151例患者作为训练集,54例患者作为验证集。用随机森林对指标预测急性心肌梗死的重要性进行排序。根据袋外数据误差,赤池信息量准则和贝叶斯信息量准则对排序指标进行筛选并构建诊断模型;多维标度法(MDS)观察模型对急性心肌梗死和心绞痛的区分能力;用验证集数据验证模型对心绞痛和急性心肌梗死的鉴别能力。 结果19个指标根据平均准确度下降程度和平均基尼(Gini)指数下降程度进行重要性排序。用袋外数据误差,赤池信息量准则和贝叶斯信息量准则筛选出C-反应蛋白、中性粒细胞绝对值和血糖3个变量,并纳入模型。通过MDS法观察到多半样本得到良好的区分,但部分样本仍难以区分开。在外部验证中,31例急性心肌梗死患者有26例(83.87%)被正确识别;在23例心绞痛患者中有19例(82.61%)被正确识别。 结论基于随机森林的诊断模型建立能较好区分急性心肌梗死与心绞痛。     

中医药治疗功能性消化不良疗效评价指标分析

目的：寻找能够准确评价中医药治疗功能性消化不良临床疗效的方法。方法：综合目前国内外采用的功能性消化不良疗效评价常用方法,并对不同的方法进行了相应的分析。结果：由于功能性消化不良与精神心理因素有密切联系,因此对其疗效评价通常需要纳入焦虑和抑郁症状的改善情况。不同的症状积分量表虽然有自己的优势,但是还是存在一定的缺陷。结论：鉴于目前医学模式的改变,有必要将临床症状和精神心理因素融合于一个量表中,寻找能够更好的评价中医药治疗功能性消化不良的临床疗效需要进一步的探索。