Abstract Survival analysis has been widely used in the field of medical research. The Cox proportional hazard model is commonly used, but its practical application is limited. Machine learning method can compensate for the shortcomings of the Cox proportional hazard model in terms of nonlinear data processing and prediction accuracy. This article reviewed the advance of machine learning methods represented by neural networks, within the field of survival analysis, and highlighted the principles and benefits of three machine learning methods that DeepSurv, Deep-Hit and random survival forest, providing methodological insights for the analysis of complex survival data.

Active immunotherapy for cancer aims to treat disease by inducing effective cellular immunity and humoral immunity.Research on virus-like particles(VLPs)vaccines has made tremendous progress in recent years,dramatically reducing morbidity and mortality from some infectious diseases.VLPs are nanoparticles self-assembled from one or more structural proteins,with highly ordered repeat sequences and good immunogenicity,which can induce strong cellular immune and humoral immune responses.VLPs can overcome immunosuppressive state of tumor microenvironment,break self-tolerance,and trigger strong cytotoxic T lymphocyte activity,which is critical for both viral clearance and destruction of cancer cells.This article mainly reviews current research progress of VLPs-based cancer vaccines and potential defects of VLPs as vaccine carriers in development of cancer vaccines.

Virus-like particles(VLPs)are nanoparticles that are self-assembled from one or more structural proteins,which can be arranged in several layers or contain a lipid outer membrane.Due to the lack of genetic material,VLPs cannot infect host cells,but are highly immunogenic and can induce immune responses different from conventional inactivated vaccines.VLPs can be produced using a variety of systems including bacterial,yeast,plant,insect and mammalian cells.Compared with traditional vaccines,VLPs have incomparable advantages,so they are becoming more and more popular in the biomedical field.To date,a series of vaccine candi-dates based on VLPs have been developed for immunization and prevention of various infectious diseases.At the same time,the recent successful application of VLPs in targeted drug delivery and gene therapy has attracted attention.This paper mainly reviews the com-monly used expression systems of VLPs and the research progress of their applications.

In order to understand the infection and molecular genetic characteristics of goose astro-virus(GAstV)in Hotan,Xinjiang,visceral organs and swabs of dead goslings were collected asep-tically from three goose farms in Hotan,Yutian and Pashan counties,and GAstV was detected by RT-PCR.The positive samples were screened and identified in LMH cells,and the whole genome was sequenced,and the genetic characteristics of the isolates were analyzed.The results showed that the total positive rate of GAstV was 11.25％(65/578).Two strains of GAstV named as GAstV/XJHT-1 and GAstV/XJHT-2 were isolated and the lengths of their genome sequences were determined as 7 190 bp and 7 125 bp,respectively.Whole genome homology analysis showed that the homology of the two isolates with GAstV-1 and GAstV-2 was higher than 95％,and the homology with other sources(chicken,duck,and turkey)ranged from 54.1％to 61.5％.Genetic e-volution analysis showed that the genetic distance between GAstV isolates from Henan and Anhui was relatively close,suggesting that the isolated GAstV may be related to the introduction of gos-lings or goose eggs from these two places.The findings provide a basis for further development of vaccines or control products.

Objective:To investigate the effect and regulation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) on islets function and NOD-like receptor family, pyrin domain containing 3 (NLRP3) and autophagy in type 2 diabetic mellitus (T2DM) mice.Methods:Experimental study. Twenty, 8-week-old, male C57BL/6J mice were selected and divided into a normal control group ( n=5) and a high-fat feeding modeling group ( n=15). The model of T2DM was established by high-fat feeding combined with intraperitoneal injection of low-dose streptozotocin. After successful modeling, those mice were divided into a diabetes group ( n=7) and a UC-MSCs treatment group ( n=7). The UC-MSCs treatment group was given UC-MSCs (1×10 6/0.2 ml phosphate buffer solution) by tail vein infusion once a week for a total of 4 weeks; the diabetes group was injected with the same amount of normal saline, and the normal control group was not treated. One week after the treatment, mice underwent intraperitoneal glucose tolerance tests and intraperitoneal insulin tolerance tests, and then the mice were sacrificed to obtain pancreatic tissue to detect the expressions of interleukin-1β (IL-1β) and pancreatic and duodenal homeobox 1 (PDX-1) by immunofluorescence. The bone marrow-derived macrophages were stimulated with lipopolysaccharide and adenosine triphosphate (experimental group) in vitro, then co-cultured with UC-MSCs for 24 h (treatment group). After the culture, enzyme-linked immunosorbent assay was used to detect the secretion level of IL-1β in the supernatant, and immunofluorescence staining was used to detect the expression of NLRP3 inflammasome, and related autophagy proteins. Statistical analysis was performed using unpaired one-way analysis of variance, repeated measure analysis of variance. Results:In vivo experiments showed that compared with the diabetes group, the UC-MSCs treatment group partially repaired islet structure, improved glucose tolerance and insulin sensitivity (all P<0.05), and the expression of PDX-1 increased and IL-1β decreased in islets under confocal microscopy. In vitro experiments showed that compared with the experimental group, the level of IL-1β secreted by macrophages in the treatment group was decreased [(85.9±74.6) pg/ml vs. (883.4±446.2) pg/ml, P=0.001], the expression of NLRP3 inflammasome and autophagy-related protein P62 was decreased, and the expressions of microtubule-associated protein 1 light chain 3β (LC3) and autophagy effector Beclin-1 were increased under confocal microscopy. Conclusions:UC-MSCs can reduce the level of pancreatic inflammation in T2DM mice, preserving pancreatic function. This might be associated with the ability of UC-MSCs to inhibit the activity of NLRP3 inflammasomes in macrophages and enhance autophagy levels.

Acute respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had caused a global pandemic since 2019, and posed a serious threat to global health security. Traditional Chinese medicine (TCM) has played an indispensable role in the battle against the epidemic. Many components originated from TCMs were found to inhibit the production of SARS-CoV-2 3C-like protease (3CLpro) and papain-like protease (PLpro), which are two promising therapeutic targets to inhibit SARS-CoV-2. This study describes a systematic investigation of the roots and rhizomes of Sophora tonkinensis, which results in the characterization of 12 new flavonoids, including seven prenylated flavanones (1-7), one prenylated flavonol (8), two prenylated chalcones (9-10), one isoflavanone (11), and one isoflavan dimer (12), together with 43 known compounds (13-55). Their structures including the absolute configurations were elucidated by comprehensive analysis of MS, 1D and 2D NMR data, and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations. Compounds 12 and 51 exhibited inhibitory effects against SARS-CoV-2 3CLpro with IC₅₀ values of 34.89 and 19.88 μmol·L^-1, repectively while compounds 9, 43 and 47 exhibited inhibitory effects against PLpro with IC₅₀ values of 32.67, 79.38, and 16.74 μmol·L^-1, respectively.
Flavonoids/chemistry* ; SARS-CoV-2 ; Rhizome ; COVID-19 ; Peptide Hydrolases ; Antiviral Agents/chemistry*

With the gradual aggravation of aging in China， the prevalence of osteoporosis is increasing year by year. Osteoporosis has become a major public health problem threatening the health of middle-aged and elderly people， especially middle-aged and elderly women. There are many predisposing factors and complex pathogenesis of osteoporosis. The interpretation of osteoporosis has been the focus of clinical research in recent years. How to prevent and treat osteoporosis more effectively has also become a major problem faced by researchers. In recent years， the balance and homeostasis of calcium and phosphorus regulated by intestinal absorption， renal excretion and bone have become one of the hot topics， and the balance and homeostasis of calcium and phosphorus in vivo are the key to normal bone homeostasis. At the same time， as a complex microbial community living in the gastrointestinal tract， intestinal flora can produce a variety of regulators affecting metabolism. It has been widely confirmed that it acts on the body indirectly or directly， in multiple ways and targets to prevent and treat osteoporosis. Therefore， further exploring the role and mechanism of intestine kidney bone axis in osteoporosis plays a far-reaching significance for the prevention and treatment of osteoporosis. In recent years， scholars have made a lot of exploration on the prevention and treatment of osteoporosis with traditional Chinese medicine （TCM）， and found that TCM can intervene the expression of intestinal flora and play the effect of prevention and treatment of osteoporosis. Based on the "intestine kidney bone axis"， this paper briefly discusses the integrated traditional Chinese and western medicine of kidney and osteoporosis， intestine and osteoporosis， intestine kidney axis， the treatment of kidney from intestine， intestine and osteoporosis， and the application of TCM in regulating intestinal flora in osteoporosis， in order to provide new ideas for the prevention and treatment of osteoporosis.

ObjectiveTo explore the effect of modified constraint-induced movement therapy (mCIMT) based on Chinese version of Quality of Upper Extremity Skills Test (Ch-QUEST) on upper limb function in children with hemiplegic cerebral palsy. MethodsFrom January to November, 2021, 40 children with hemiplegic cerebral palsy in Xuzhou Rehabilitation Hospital were recruited and randomly divided into control group (n = 20) and observation group (n = 20). The control group received routine upper limb function training, and the observation group received mCIMT based on Ch-QUEST additionally, for twelve weeks. They were assessed with Ch-QUEST, Peabody Developmental Motor Scale-Fine Motor (PDMS-FM) and Function Independence Measure for Children (WeeFIM) before and after treatment. ResultsAfter treatment, the scores of Ch-QUEST, DMS-FM (raw score) and WeeFIM significantly increased in both groups (|t| > 3.432, P < 0.01), and were higher in the observation group than in the control group (t > 2.032, P < 0.05). ConclusionmCIMT based on Ch-QUEST could improve the upper limb function of children with hemiplegic cerebral palsy.

BACKGROUND: Gestational diabetes mellitus (GDM) brings health issues for both mothers and offspring, and GDM prevention is as important as GDM management. It was shown that a history of GDM was significantly associated with a higher maternal risk for GDM recurrence. The incidence of GDM recurrence was unclear because of the incidence of second-child was low before 2016 in China. We aim to investigate the prevalence of GDM recurrence and its associated high-risk factors which may be useful for the prediction of GDM recurrence in China. METHODS: A retrospective study was conducted which enrolled participants who underwent regular prenatal examination and delivered twice in the same hospital of 18 research centers. All participants were enrolled from January 2018 to October 2018, where they delivered the second baby during this period. A total of 6204 women were enrolled in this study, and 1002 women with a history of GDM were analyzed further. All participants enrolled in the study had an oral glucose tolerance test (OGTT) result at 24 to 28 weeks and were diagnosed as GDM in the first pregnancy according to the OGTT value (when any one of the following values is met or exceeded to the 75-g OGTT: 0 h [fasting], ≥5.10 mmol/L; 1 h, ≥10.00 mmol/L; and 2 h, ≥8.50 mmol/L). The prevalence of GDM recurrence and development of type 2 diabetes mellitus were calculated, and its related risk factors were analyzed. RESULTS: In 6204 participants, there are 1002 women (1002/6204,16.15%) with a history of GDM and 5202 women (5202/6204, 83.85%) without a history of GDM. There are significant differences in age (32.43 ± 4.03 years vs. 33.00 ± 3.34 years vs. 32.19 ± 3.37 years, P  < 0.001), pregnancy interval (4.06 ± 1.44 years vs. 3.52 ± 1.43 years vs. 3.38 ± 1.35 years, P  = 0.004), prepregnancy body mass index (BMI) (27.40 ± 4.62 kg/m2vs. 23.50 ± 3.52 kg/m2vs. 22.55 ± 3.47 kg/m2, P < 0.001), history of delivered macrosomia (22.7% vs. 11.0% vs. 6.2%, P < 0.001) among the development of diabetes mellitus (DM), recurrence of GDM, and normal women. Moreover, it seems so important in the degree of abnormal glucose metabolism in the first pregnancy to the recurrence of GDM and the development of DM. There are significant differences in OGTT levels of the first pregnancy such as area under the curve of OGTT value (18.31 ± 1.90 mmol/L vs. 16.27 ± 1.93 mmol/L vs. 15.55 ± 1.92 mmol/L, P < 0.001), OGTT fasting value (5.43 ± 0.48 mmol/L vs. 5.16 ± 0.49 mmol/L vs. 5.02 ± 0.47 mmol/L, P < 0.001), OGTT 1-hour value (10.93 ± 1.34 mmol/L vs. 9.69 ± 1.53 mmol/L vs. 9.15 ± 1.58 mmol/L, P < 0.001), OGTT 2-hour value (9.30 ± 1.66 mmol/L vs. 8.01 ± 1.32 mmol/L vs. 7.79 ± 1.38 mmol/L, P < 0.001), incidence of impaired fasting glucose (IFG) (fasting plasma glucose ≥5.6 mmol/L) (31.3% vs. 14.6% vs. 8.8%, P < 0.001), and incidence of two or more abnormal OGTT values (68.8% vs. 39.7% vs. 23.9%, P < 0.001) among the three groups. Using multivariate analysis, the factors, such as age (1.07 [1.02-1.12], P = 0.006), prepregnancy BMI (1.07 [1.02, 1.12], P  = 0.003), and area under the curve of OGTT in the first pregnancy (1.14 [1.02, 1.26], P  = 0.02), have an effect on maternal GDM recurrence; the factors, such as age (1.28 [1.01-1.61], P  = 0.04), pre-pregnancy BMI (1.26 [1.04, 1.53], P = 0.02), and area under the curve of OGTT in the first pregnancy (1.65 [1.04, 2.62], P = 0.03), have an effect on maternal DM developed further. CONCLUSIONS The history of GDM was significantly associated with a higher maternal risk for GDM recurrence during follow-up after the first pregnancy. The associated risk factors for GDM recurrence or development of DM include age, high pre-pregnancy BMI, history of delivered macrosomia, the OGTT level in the first pregnancy, such as the high area under the curve of OGTT, IFG, and two or more abnormal OGTT values. To prevent GDM recurrence, women with a history of GDM should do the preconception counseling before preparing next pregnancy.
Adult ; Blood Glucose/metabolism* ; China/epidemiology* ; Diabetes Mellitus, Type 2/epidemiology* ; Diabetes, Gestational ; Female ; Fetal Macrosomia ; Glucose Intolerance ; Humans ; Male ; Pregnancy ; Retrospective Studies

Objective:To explore the effects of interpregnancy interval (IPI) on pregnancy outcomes of subsequent pregnancy.Methods:A multicenter retrospective study was conducted in 21 hospitals in China. Information of age, height, pre-pregnancy weight, IPI, history of diseases, complications of pregnancy, gestational age of delivery, delivery mode, and pregnancy outcomes of the participants were collected by consulting medical records of pregnant women who had two consecutive deliveries in the same hospital during 2011 to 2018. The participants were divided into 4 groups according to IPI:<18 months, 18-23 months, 24-59 months and ≥60 months. According to the WHO′s recommendation, with the IPI of 24-59 months group as a reference, to the effects of IPI on pregnancy outcomes of subsequent pregnancy were analyzed. Stratified analysis was further carried out based on age, history of gestational diabetes mellitus (GDM), macrosomia, and premature delivery, to explore the differences in the effects of IPI on pregnancy outcomes among women with different characteristics.Results:A total of 8 026 women were included in this study. There were 423, 623, 5 512 and 1 468 participants in <18 months group, 18-23 months group, 24-59 months group and ≥60 months group, respectively. (1) The age, pre-pregnancy body mass index (BMI), history of cesarean section, GDM, gestational hypertension and cesarean section delivery rate of <18 months group, 18-23 months group, 24-59 months group and ≥60 months group were gradually increased, and the differences were statistically significant ( P<0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 24-59 months group, the risk of premature delivery, premature rupture of membranes, and oligohydramnios were increased by 42% ( OR=1.42, 95% CI: 1.07-1.88, P=0.015), 46% ( OR=1.46, 95% CI: 1.13-1.88, P=0.004), and 64% ( OR=1.64, 95% CI: 1.13-2.38, P=0.009) respectively for women in the IPI≥60 months group. No effects of IPI on other pregnancy outcomes were found in this study ( P>0.05). (3) After stratified by age and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of oligohydramnios for women with advanced age ( OR=2.87, 95% CI: 1.41-5.83, P=0.004); and <18 months could increase the risk of premature rupture of membranes for women under the age of 35 ( OR=1.59, 95% CI: 1.04-2.43, P=0.032). Both the risk of premature rupture of membranes ( OR=1.58, 95% CI: 1.18-2.13, P=0.002) and premature delivery ( OR=1.52, 95% CI: 1.07-2.17, P=0.020) were significantly increased in the IPI≥60 months group. After stratified by history of GDM and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would lead to an increased risk of postpartum hemorrhage for women with a history of GDM ( OR=5.34, 95% CI: 1.45-19.70, P=0.012) and an increased risk of premature rupture of membranes for women without a history of GDM ( OR=1.44, 95% CI: 1.10-1.90, P=0.009). After stratified by history of macrosomia and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months could increase the proportion of cesarean section for women with a history of macrosomia ( OR=4.11, 95% CI: 1.18-14.27, P=0.026) and the risk of premature rupture of membranes for women without a history of macrosomia ( OR=1.46, 95% CI: 1.12-1.89, P=0.005). After stratified by history of premature delivery and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of premature rupture of membranes for women without a history of premature delivery ( OR=1.47, 95% CI: 1.13-1.92, P=0.004). Conclusions:Both IPI≥60 months and <18 months would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women of reproductive age to maintain an appropriate IPI when they plan to pregnant again, to reduce the risk of adverse pregnancy outcomes in the subsequent pregnancy.