Development and validation of a nomogram for predicting in-hospital mortality of intensive care unit patients with liver cirrhosis

BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality rate.AIM To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver cirrhosis.METHODS We extracted demographic,etiological,vital sign,laboratory test,comorbidity,complication,treatment,and severity score data of liver cirrhosis patients from the Medical Information Mart for Intensive Care IV(MIMIC-IV)and electronic ICU(eICU)collaborative research database(eICU-CRD).Predictor selection and model building were based on the MIMIC-IV dataset.The variables selected through least absolute shrinkage and selection operator analysis were further screened through multivariate regression analysis to obtain final predictors.The final predictors were included in the multivariate logistic regression model,which was used to construct a nomogram.Finally,we conducted external validation using the eICU-CRD.The area under the receiver operating characteristic curve(AUC),decision curve,and calibration curve were used to assess the efficacy of the models.RESULTS Risk factors,including the mean respiratory rate,mean systolic blood pressure,mean heart rate,white blood cells,international normalized ratio,total bilirubin,age,invasive ventilation,vasopressor use,maximum stage of acute kidney injury,and sequential organ failure assessment score,were included in the multivariate logistic regression.The model achieved AUCs of 0.864 and 0.808 in the MIMIC-IV and eICU-CRD databases,respectively.The calibration curve also confirmed the predictive ability of the model,while the decision curve confirmed its clinical value.CONCLUSION The nomogram has high accuracy in predicting in-hospital mortality.Improving the included predictors may help improve the prognosis of patients.

Progress in in vitro culture and gene editing of porcine spermatogonial stem cells

Research on in vitro culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their in vitro culture, potential usage, and genetic manipulation. Furthermore, we discuss the current application of gene editing in pig cloning technology. Collectively, this commentary aims to summarize the progress made and obstacles encountered in porcine SSC research to better serve animal husbandry, improve livestock fecundity, and enhance potential clinical use.

Hyperactive reactive oxygen species impair function of porcine Sertoli cells via suppression of surface protein ITGB1 and connexin-43

DEAR EDITOR,Gap junctions regulate intercellular communication between Sertoli cells and germ cells in male testes and play vital functions in spermatogenesis.Many factors in animal breeding and husbandry can induce oxidative stress,which can impair the testis microenvironment and male animal fertility.However,the underlying mechanisms are largely unknown.Recently,we identified that androgen signals promote the expression of connexin-43(Cx43),a key component of gap junctions,to regulate spermatogenesis.Thus,we asked whether hyperactive reactive oxygen species(ROS)can impair gap junctions by interfering with Cx43 in porcine testes.Using a porcine Sertoli cell in vitro system,we found that hyperactive ROS caused extensive apoptosis in Sertoli cells,remarkable decrease in Cx43 expression,and failed maintenance of co-cultured spermatogonial stem cells(SSCs),indicating that ROS impaired the function of Sertoli cells and promoted loss of SSCs.This observation provides a possible mechanism for the impact of ROS on fertility of male animals.

Projected burden of stroke in China through 2050

Background:Stroke is the leading cause of death in China,and predicting the stroke burden could provide essential information guiding the setting of medium-and long-term health policies and priorities.The study aimed to project trends associated with stroke burden in China through 2050,not only in terms of incidence and mortality but also for prevalence and disability-adjusted life years(DALYs).Methods:Data on stroke rates in incidence,prevalence,deaths,and DALYs in China between 1990 and 2019 were obtained from a recent Global Burden of Disease study.Demographic-specific trends in rates over time were estimated using three models:the loglinear model,the Lee-Carter model,and a functional time series model.The mean absolute percentage error and the root mean squared error were used for model selection.Projections up to 2050 were estimated using the best fitting model.United Nations population data were used to project the absolute numbers through 2050.Results:From 2019 to 2050,the crude rates for all measures of the stroke burden are projected to increase continuously among both men and women.We project that compared with those in 2019,the incidence,prevalence,deaths,and DALYs because of stroke in China in 2050 will increase by 55.58%,119.16%,72.15%,and 20.04%,respectively;the corresponding increases in number were 2.19,34.27,1.58,and 9.21 million.The age-standardized rate is projected to substantially decline for incidence(8.94%),death(40.37%),and DALYs(43.47%),but the age-standardized prevalence rate is predicted to increase by 10.82%.By 2050,the burden of stroke among the population aged≥65 years will increase significantly:by 104.70%for incidence,by 218.48%for prevalence,by 100.00%for death,and by 58.93%for DALYs.Conclusions:With the aging population in China increasing over the next three decades,the burden of stroke will be markedly increased.Continuous efforts are needed to improve stroke health care and secondary prevention,especially for older adults.

Association between Maternal Weight Indicators and Iron Deficiency Anemia during Pregnancy： A Cohort Study

Background： The effect of maternal weights on the risk of iron deficiency anemia （IDA） during pregnancy remains unclear. The study aimed to investigate the association between maternal weight indicators and IDA during pregnancy. Methods： We conducted a cohort study to examine the association between maternal weight indicators, including prepregnancy body mass index and the rate of gestational weight gain （GWG）, and the risk of IDA among Chinese pregnant women. Data about new-onset IDA at different trimesters from a national cross-sectional survey were collected; information regarding baseline variables and rate of GWG from women participating in the survey were retrospectively collected. Tested IDA and reported IDA were documented. Multilevel logistic regression to examine the association between maternal weight indicators and the risk of IDA after adjusting for potential confounders was conducted. Results： This study enrolled 11,782 pregnant women from 24 hospitals from September 19, 2016, to November 20, 2016. Among those, 1515 （12.9%） IDA events were diagnosed through test （test IDA）： 3915 （33.3%） were identified through test and patient reporting （composite IDA）. After adjusting for confounders and cluster effect of hospitals, underweight pregnant women, compared with normal women, were associated with higher risk of test IDA （adjusted odds ratio [aOR]： 1.35, 95% confidence interval [CI]： 1.17-1.57 and composite IDA （aOR： 1.35, 95% CI： 1.21-1.51）; on the contrary, overweight and obese women had lower risk of test IDA （aOR： 0.68, 95% CI： 0.54-0.86 overweight; aOR： 0.30, 95% CI： 0. 13-0.69 obese） and composite IDA （aOR： 0.77, 95% （71：0.67-0.90 overweight; aOR： 0.34, 95% CI： 0.21-0.55 obese）. The higher rate of GWG was associated with higher risk of IDA （test aOR： 1.86 95% CI： 1.26-2.76; composite aOR： 1.54, 95% CI： 1.16-2.03）. Conclusions： Pregnant women who are underweight betbre pregnancy and who have taster GWG are more likely to develop IDA. Enforced weight control during pregnancy and use of iron supplements, particularly among underweight women, may be warranted.

Production of transgenic mice by random recombination of targeted genes in female germline stem cells

Oocyte production in most mammalian species is believed to cease before birth.However,this idea has been challenged with the finding that postnatal mouse ovaries possess mitotically active germ cells.A recent study showed that female germline stem cells(FGSCs)from adult mice were isolated,cultured long term and produced oocytes and progeny after transplantation into infertile mice.Here,we demonstrate the successful generation of transgenic or gene knock-down mice using FGSCs.The FGSCs from ovaries of 5-day-old and adult mice were isolated and either infected with recombinant viruses carrying green fluorescent protein,Oocyte-G1 or the mouse dynein axonemal intermediate chain 2 gene,or transfected with the Oocyte-G1 specific shRNA expression vector(pRS shOocyte-G1 vector),and then transplanted into infertile mice.Transplanted cells in the ovaries underwent oogenesis and produced heterozygous offspring after mating with wild-type male mice.The offspring were genetically characterized and the biological functions of the transferred or knock-down genes were investigated.Efficiency of genetransfer or gene knock-down was 29%–37%and it took 2 months to produce transgenic offspring.Gene manipulation of FGSCs is a rapid and efficient method of animal transgenesis and may serve as a powerful tool for biomedical science and biotechnology.