The composite risk index based on frailty predicts postoperative complications in older patients recovering from elective digestive tract surgery: a retrospective cohort study.

BACKGROUND: Limitations exist in available studies investigating effect of preoperative frailty on postoperative outcomes. This study was designed to analyze the association between composite risk index, an accumulation of preoperative frailty deficits, and the risk of postoperative complications in older patients recovering from elective digestive tract surgery. METHODS: This was a retrospective cohort study. Baseline and perioperative data of older patients (age ≥ 65 years) who underwent elective digestive tract surgery from January 1, 2017 to December 31, 2018 were collected. The severity of frailty was assessed with the composite risk index, a composite of frailty deficits including modified frailty index. The primary endpoint was the occurrence of postoperative complications during hospital stay. The association between the composite risk index and the risk of postoperative complications was assessed with a multivariable logistic regression model. RESULTS: A total of 923 patients were included. Of these, 27.8% (257) developed postoperative complications. Four frailty deficits, i.e., modified frailty index ≥0.27, malnutrition, hemoglobin < 90 g/L, and albumin ≤30 g/L, were combined to generate a composite risk index. Multivariable analysis showed that, when compared with patients with composite risk index of 0, the odds ratios (95% confidence intervals) were 2.408 (1.714-3.383, P <  0.001) for those with a composite risk index of 1, 3.235 (1.985-5.272, P <  0.001) for those with a composite risk index of 2, and 9.227 (3.568-23.86, P <  0.001) for those with composite risk index of 3 or above. The area under receiver-operator characteristic curve to predict postoperative complications was 0.653 (95% confidence interval 0.613-0.694, P <  0.001) for composite risk index compared with 0.622 (0.581-0.663, P <  0.001) for modified frailty index. CONCLUSION: For older patients following elective digestive tract surgery, high preoperative composite risk index, a combination of frailty deficits, was independently associated with an increased risk of postoperative complications.

Severe functional impairment increases the risk of major morbidity and mortality in older patients after digestive tract surgery: a retrospective cohort study.

PURPOSE: The relationship between the severity of impairment in basic activities of daily living (ADLs) function and postoperative outcomes in older surgical patients remains unclear. This study aimed to clarify the association between the severity of preoperative functional impairment and the composite postoperative outcome of major morbidity and mortality in older patients undergoing digestive tract surgery. METHODS: This was a retrospective cohort study. We collected perioperative data of older patients (age ≥ 65 years) who underwent digestive tract surgery in our institution. The severity of functional impairment was assessed using the Barthel Index scale before surgery. The major morbidity and mortality were defined as Clavien-Dindo grade III or greater postoperative complications during hospital stay. The association between the severity of functional impairment and the major morbidity and mortality was assessed using a multivariable logistic regression model. RESULTS: 131 of 1076 patients (12.2%) developed major morbidity and mortality. After controlling for confounding factors, high Barthel Index scores were correlated with decreased risk of major morbidity and mortality (OR 0.986, 95% CI 0.976-0.997, P = 0.011); preoperative severe (OR 2.862, 95% CI 1.172-6.989, P = 0.021), but not mild or moderate (OR 1.019, 95% CI 0.602-1.726, P = 0.943) functional impairment was independently associated with an increased risk of major morbidity and mortality, when compared with independent functional status. CONCLUSIONS: Preoperative severe functional impairment in basic ADLs was independently associated with a higher risk of major postoperative morbidity and mortality in older patients undergoing digestive tract surgery.

A Metagenomic Study of Intestinal Microbial Diversity in Relation to Feeding Habits of Surface and Cave-Dwelling Sinocyclocheilus Species.

Light is completely absent in cave habitats, causing a shortage or lack of autochthonous photosynthesis. Thus, understanding the mechanisms underlying the ability of organisms to adapt to the unique cave habitat is of great interest. We used high-throughput sequencing of the 16S ribosomal RNA gene of intestinal microorganisms from 11 Sinocyclocheilus (Cypriniformes: Cyprinidae) species, to explore the characteristics of intestinal microorganisms and the adaptive mechanisms of Sinocyclocheilus cavefish and surface fish. We found that the α-diversity and richness of the intestinal microbiome were much higher in cavefish than in surface fish. Principal coordinate analysis showed that cavefish and surface fish formed three clusters because of different dominant gut microorganisms which are generated by different habitats. Based on PICRUSt-predicted functions, harmful substance degradation pathways were much more common in cavefish intestinal microorganisms than in those from surface fish. The intestinal microbiota of surface fish group 1 had a higher capacity for carbohydrate metabolism, whereas protein and amino acid metabolism and digestive pathways were more abundant in microorganisms from the cavefish group and surface fish group 2. Combined analysis of the intestinal microbial composition and functional predictions further revealed the structures and functions of intestinal microbial communities in Sinocyclocheilus cave and surface species. Moreover, based on their habits and intestinal microbial composition and intestinal microbial functional predictions, we inferred that the three fish groups were all omnivorous; however, surface fish group 1 preferred feeding on plants, while surface fish group 2 and cavefish preferred meat. This study improves our understanding of mechanisms of adaptation in cave habitats and may contribute to the protection of these habitats from water pollution.

Low vitamin D levels are associated with high viral loads in patients with chronic hepatitis B: a systematic review and meta-analysis.

BACKGROUND: Previous studies have investigated the vitamin D status in patients with chronic hepatitis B virus (HBV) infection and its relationship with HBV replication, the results however were inconsistent. The present meta-analysis was carried out to compare the vitamin D levels between patients with chronic hepatitis B (CHB) and healthy controls, and to determine whether vitamin D levels were correlated with HBV viral loads significantly. METHODS: A systematic search was conducted via PubMed, Web of Science, EMBASE and the Cochrane Library to identify eligible studies until September 28, 2017. We calculated pooled mean difference (MD) and 95% confidence intervals (CI) to quantitatively estimate the difference of vitamin D levels between CHB patients and controls. In addition, correlation between serum vitamin D levels and HBV viral loads was defined by summary correlation coefficient (r value) and the corresponding 95% CI. RESULTS: A total of 7 studies involving 814 CHB patients and 696 healthy controls were included. A significantly decreased vitamin D levels was found in CHB patients compared with healthy controls: pooled MD (95% CI) was - 2.03 ng/mL (- 2.60, - 1.46). Latitude-stratified subgroup analysis indicated this difference was more obvious in low latitude areas, with a bigger pooled MD (95% CI) of - 2.72 ng/mL (- 4.57, - 0.87). In addition, we observed an inverse correlation between serum vitamin D levels and HBV viral loads: pooled r (95% CI) was - 0.41(- 0.54, - 0.27). CONCLUSIONS: Our results showed that vitamin D levels were lower in CHB patients than that of healthy controls and inversely correlated with HBV viral loads, although future comprehensive studies are needed to clarify the underlying mechanisms.

miR-34b Alleviates High Glucose-Induced Inflammation and Apoptosis in Human HK-2 Cells via IL-6R/JAK2/STAT3 Signaling Pathway.

BACKGROUND It is well established that inflammation and apoptosis of renal tubular epithelial cells caused by hyperglycemia contribute to the development of diabetic nephropathy (DN). Although microRNAs (miRNAs) are known to have roles in inflammation-related disorders, the exact role of miR-34b in DN has not been defined, and the regulatory mechanism has been unclear. This study aimed to clarify the role of miR-34b in DN pathogenesis. MATERIAL AND METHODS Expression of miR-34b, IL-6R, and other key factors of inflammation, apoptosis (TNF-alpha, IL-1ß, IL-6, caspase-3) in high glucose (HG)-induced HK-2 cells were measured by real-time PCR, Western blot, and flow cytometric cell apoptosis assays. We used luciferase reporter assay to detect the target of miR-34b. Moreover, the targeting gene of miR-34b and its downstream JAK2/STAT3 signaling pathway were explored. RESULTS It was demonstrated that miR-34b overexpression inhibited apoptosis and expression levels of TNF-alpha, IL-1ß, IL-6, and caspase-3 in HG-treated HK-2 cells. We also found that IL-6R is a direct target of miR-34b, which could rescue inflammation and apoptosis in HG-treated HK-2 cells transfected with miR-34b mimic. Furthermore, we showed that overexpression of miR-34b inhibited the IL-6R/JAK2/STAT3 signaling pathway in HG-treated HK-2 cells. CONCLUSIONS Our data suggest that overexpression of miR-34b improves inflammation and ameliorates apoptosis in HG-induced HK-2 cells via the IL-6R/JAK2/STAT3 pathway, indicating that miR-34b could be a promising therapeutic target in DN.

Genomic diversity and admixture patterns among six Chinese indigenous cattle breeds in Yunnan.

OBJECTIVE: Yunnan is not only a frontier zone that connects China with South and Southeast Asia, but also represents an admixture zone between taurine (Bos taurus) and zebu (Bos indicus) cattle. The purpose of this study is to understand the level of genomic diversity and the extent of admixture in each Yunnan native cattle breed. METHODS: All 120 individuals were genotyped using Illumina BovineHD BeadChip (777,962 single nucleotide polymorphisms [SNPs]). Quality control and genomic diversity indexes were calculated using PLINK software. The principal component analysis (PCA) was assessed using SMARTPCA program implemented in EIGENSOFT software. The ADMIXTURE software was used to reveal admixture patterns among breeds. RESULTS: A total of 604,630 SNPs was obtained after quality control procedures. Among six breeds, the highest level of mean heterozygosity was found in Zhaotong cattle from Northeastern Yunnan, whereas the lowest level of heterozygosity was detected in Dehong humped cattle from Western Yunnan. The PCA based on a pruned dataset of 233,788 SNPs clearly separated Dehong humped cattle (supposed to be a pure zebu breed) from other five breeds. The admixture analysis further revealed two clusters (K = 2 with the lowest cross validation error), corresponding to taurine and zebu cattle lineages. All six breeds except for Dehong humped cattle showed different degrees of admixture between taurine and zebu cattle. As expected, Dehong humped cattle showed no signature of taurine cattle influence. CONCLUSION: Overall, considerable genomic diversity was found in six Yunnan native cattle breeds except for Dehong humped cattle from Western Yunnan. Dehong humped cattle is a pure zebu breed, while other five breeds had admixed origins with different extents of admixture between taurine and zebu cattle. Such admixture by crossbreeding between zebu and taurine cattle facilitated the spread of zebu cattle from tropical and subtropical regions to other highland regions in Yunnan.

Microscopic and Submicroscopic Gradient Variation of Olfactory Systems among Six Sinocyclocheilus Species Living in Different Environments.

The fish genus Sinocyclocheilus contains many different species that inhabit diverse natural environments, such as surface water layer, cave, or intermediate. As a result of these different habitats there are some differences in their sensory systems. Microscopic and submicroscopic structures of olfactory systems in six representative species of Sinocyclocheilus were studied, including one surface-dwelling species (S. grahami), two intermediate species (S. jii and S. macrophthalmus) and three cave-dwelling species (S. brevibarbatus, S. anshuiensis, and S. tianlinensis). Due to adaptive evolution under extreme environmental conditions, cave-dwelling species have more developed olfactory systems. We observed that, compared with surface-dwelling species, the olfactory sac of the cave-dwelling Sinocyclocheilus species has the following characteristics: higher density of cilia, greater length of sensory cilia, many other special structures (micro-ridge, olfactory islet, rod cilia). These results reveal different levels of olfactory system development, consistent with the view that that cave-dwelling species have more developed olfactory systems than intermediate and surface-dwelling species.

Selection of emission factor standards for estimating emissions from diesel construction equipment in building construction in the Australian context.

Emissions from equipment usage and transportation at the construction stage are classified as the direct emissions which include both greenhouse gas (GHG) and non-GHG emissions due to partial combustion of fuel. Unavailability of a reliable and complete inventory restricts an accurate emission evaluation on construction work. The study attempts to review emission factor standards readily available worldwide for estimating emissions from construction equipment. Emission factors published by United States Environmental Protection Agency (US EPA), Australian National Greenhouse Accounts (AUS NGA), Intergovernmental Panel on Climate Change (IPCC) and European Environmental Agency (EEA) are critically reviewed to identify their strengths and weaknesses. A selection process based on the availability and applicability is then developed to help identify the most suitable emission factor standards for estimating emissions from construction equipment in the Australian context. A case study indicates that a fuel based emission factor is more suitable for GHG emission estimation and a time based emission factor is more appropriate for estimation of non-GHG emissions. However, the selection of emission factor standards also depends on factors like the place of analysis (country of origin), data availability and the scope of analysis. Therefore, suitable modifications and assumptions should be incorporated in order to represent these factors.

A Plasma Exosomal Metabolic Profiling of Nonalcoholic Fatty Liver Disease Patients Complicated with Impaired Fasting Glucose.

BACKGROUND/AIMS: Nonalcoholic fatty liver disease is considered as the hepatic manifestation of metabolic syndrome. Detection of circulating exosomes together with metabolomic analysis of their cargo would provide early signals for metabolic derangements and complications associated with nonalcoholic fatty liver disease. Therefore, this study profiled exosomal metabolome of patients with nonalcoholic fatty liver disease and impaired fasting glucose. MATERIALS AND METHODS: Plasma exosomes were extracted from nonalcoholic fatty liver disease patients with or without impaired fasting glucose through differential ultracentrifugation. Their metabolite profiles were examined by ultrahigh-performance liquid chrom atography-quadrupole time-of-flight mass spectrometry. Pathway analysis was carried out on platform MetaboAnalyst 4.0. RESULTS: Thirty-nine patients were enrolled, including nonalcoholic fatty liver disease-alone group (n = 26) and age-and gender-comparable nonalcoholic fatty liver disease plus impaired fasting glucose group (n = 13). Although less than and different from their plasma counterparts, a total of 10 significantly differential exosomal metabolites were identified. Nonalcoholic fatty liver disease plus impaired fasting glucose group had higher concentrations of linoleic acid, palmitamide, stearamide, and oleamide, as well as a lower concentration of phosphatidylethanolamine [20:5(5Z,8Z,11Z,14Z,17Z)/20:5(5Z,8Z,11Z,14Z,17Z)]. Pathway analysis showed an obviously changed metabolism of linoleic acid. CONCLUSION: Metabolomic analysis of plasma exosomes revealed a distinct change in fatty acids and related pathways in nonalcoholic fatty liver disease patients with impaired fasting glucose. These preliminary results provide a metabolomic snapshot and basis for further investigation of exosome biology for these patients.

[Differential expressions of miRNAs in kidney in puromycin aminonucleoside nephropathy model and intervened effects of Leizhi capsule].

OBJECTIVE: To observe the differential expression characteristics of microRNAs (miRNAs) in renal tissues in puromycin aminonucleoside (PAN) nephritic model, and its relationship with key structural molecules of slid diaphragm (SD) nephrin and podocin and expression of skeleton protein synaptopodin; and to explore the in vivo mechanisms of Leizhi capsule (LZC) for ameliorating the expressions of nephrin, podocin and synaptopodin and reducing proteins by regulating the modal rat renal tissues miRNAs. METHOD: Fifty male Wistar rats were randomly divided into five groups: the control group (A), the model group (B), the LZC-treated group (C), the multi-glycoside of Tripterygium wilfordii (GTW)-treated group (D) and the valsartan-treated group (E). Apart from group A, all of rats in the remaining groups are injected with PAN (100 mg x kg(-1)) through jugular veins to establish the PAN nephropathy model. On the 2nd day after PAN nephropathy model was established, group C was orally administered with LZC (5 mL x kg(-1) x d(-1)) in group C, group DGTW (10 mL x kg(-1) x d(-1)), and E group valsartan (7.5 mL x kg(-1) x d(-1)), while groups A and B were intervened with physiological saline, for 10 days. Body weight and 24 h urinary protein ration (Upro) in all rats were measured at day 0, 3, and 9. All rats were sacrificed at day 11 after the establishment of the model, and their blood and renal tissues were collected to observe such blood biochemical indicators including albumin (Alb), serum creatinine (Scr), blood urea nitrogen (BUN) and glomerular ultrastructure (podocyte foot process form) and expressions of dicer enzyme, nephrin, podocin and synaptopodin in renal tissues. Meanwhile, the differential expressional characteristics of miRNAs in renal cortex were analyzed by biochip assay. Additionally, the differential expressional volumes of rno-miR-23a, rno-miR-300-3p, rno-miR-24 and rno-miR-30c were measured by real-time PCR. RESULT: Proteinuria, renal dysfunction, hypoproteinemia and podocyte foot process fusion were investigated in model rats induced by PAN. In renal tissues of PAN nephropathy model rats, dicer enzyme affected the expressions of nephrin, podocin and synaptopodin in podocytes, up-regulated the expressions of rno-miR-23a and rno-miR-300-3p, and down-regulated the expressions of rno-miR-24 and rno-miR-30c. The miRNAs with differential expressions included rno-miR-24, rno-miR-30c, rno-miR-23a and rno-miR-300-3p. LZC could improve the general state, proteinuria, serum BUN and podocyte foot process fusion of PAN nephropathy model rats, reduced the expressions of dicer enzyme, increased the expressions of nephrin, podocin and synaptopodin in podocytes, weakened the up-regulated rno-miR-23a and rno-miR-300-3p, and strengthened the down-regulated rno-miR-24 and rno-miR-30c in renal tissues. CONCLUSION: PAN in vivo impacts the expressions of miRNAs in renal tissues, intervenes the expressions of nephrin, podocin and synaptopodin in podocytes, damages podocyte structures and functions and generates proteinuria by means of differential expression of dicer enayme/miRNAs. LZC can reduce proteinuria in PAN nephropathy model rats. Its mechanism may intervene dicer enayme/miRNAs differential expression, regulate nephrin, podocin and synaptopodin in podocytes and improve podocyte structures and functions.

Effects of the Education and Training Programme for Excellent Physicians in China on medical students' academic performance: a cross-sectional study.

OBJECTIVES: To evaluate the effect of the Education and Training Programme for Excellent Physicians in China on medical students' academic performance. DESIGN: This study is a secondary analysis of data from a cross-sectional survey of China Medical Student Survey (CMSS, 2021) and administrative data of the first-stage Medical Licensing Examination-the Standardised Competence Test for Clinical Medicine Undergraduates (the Test, 2021). CMSS used a stratified sampling process, with all undergraduate clinical medicine students participating voluntarily. SETTING: This programme is implemented at the class level within reformed medical schools, targeting undergraduate students in 5-year clinical medicine in China. The reformed medical schools run pilot classes and traditional classes simultaneously. The analytic sample was a total of 12 243 observations from pilot and traditional classes in 34 medical schools which implemented the reform across 19 provinces in China. METHODS: This study applied the propensity score matching method to estimate the effect of the reform by comparing the scores of the Test between pilot and traditional classes within the same medical schools. We further explored the potential mechanisms driving the effect from two facets of the Test: medical knowledge modules and cognitive levels. RESULTS: Pilot classes outperformed traditional classes by 0.104 SD on the Test (95% CI 0.037 to 0.171). Improvements were seen in basic medicine and clinical medicine modules (0.109 and 0.101 SD, respectively) and cognitive levels of memorisation and application (0.116 and 0.111 SD, respectively). CONCLUSION: These results suggest that the reform had a significant positive impact on medical students' academic performance. Based on the components of this reform and the potential mechanism analysis of the two facets, this study indicates that curriculum reform in integrated learning and teaching methods reform in the adoption of problem-based learning may have been the possible drivers of this positive impact.

Supreme laryngeal mask airway for cesarean section under general anesthesia: a 10-year retrospective cohort study.

Background: Previous research showed the use of supraglottic airways in obstetric anesthesia. The relevant evidence of laryngeal mask airway (LMA) on maternal and neonatal outcomes is still limited. We aimed to assess the maternal and neonatal outcomes when the LMA Supreme was used for cesarean section under general anesthesia. Methods: We included all patients who underwent general anesthesia for cesarean section between January 2010 and December 2019. Propensity score matching was used to reduce potential bias from non-random selection of airway intervention. The primary outcome was adverse maternal and neonatal outcomes defined as maternal regurgitation, aspiration, hypoxemia, and low neonatal Apgar scores. Secondary outcomes included patient admission to the intensive care unit, neonate required tracheal intubation, external cardiac massage, and admission to the neonatal intensive care unit. Results: A total of 723 patients were included in the analysis; of whom, 221 received Supreme laryngeal mask airway (LMA group) and 502 were intubated with an endotracheal tube (ETT group). After propensity score matching, 189 patients remained in each group. No episode of regurgitation and aspiration occurred in both groups. There was no difference in the rates of Apgar score below 7 at 1 min (14.3% LMA group vs. 15.3% ETT group, OR 0.931, 95% CI 0.574 to 1.510, P = 0.772) and 5 min (3.7% vs. 4.2%, OR 0.875, 95% CI 0.324 to 2.365, P = 0.792). No difference was observed in the secondary outcomes between the two groups. Conclusion: The LMA Supreme was not associated with higher adverse maternal and neonatal outcomes when compared to an endotracheal tube for cesarean section under general anesthesia. It might be considered an alternative to tracheal intubation in obstetric practice.

Immunoregulation mechanism of VEGF signaling pathway inhibitors and its efficacy on the kidney.

Angiogenesis and immunosuppression are closely related pathophysiologic processes. Widely prescribed in malignant tumor and proliferative retinal lesions, VEGF signaling pathway inhibitors may cause hypertension and renal injury in some patients, presenting with proteinuria, nephrotic syndrome, renal failure and thrombotic microangiopathy. VEGF signaling pathway inhibitors block the action of both VEGF-A and VEGF-C. However, VEGF-A and VEGF-C produced by podocytes are vital to maintain the physiological function of glomerular endothelial cells and podocytes. There is still no effective treatment for kidney disease associated with VEGF signaling pathway inhibitors and some patients have progressive renal failure even after withdrawal of the drug. Recent studies reveal that blocking of VEGF-A and VEGF-C can activate CD4 +and CD8+ T cells, augment antigen-presenting function of dendritic cells, enhance cytotoxicity of macrophages and initiate complement cascade activation. VEGF and VEGFR are expressed in immune cells, which are involved in the immunosuppression and cross-talk among immune cells. This review summarizes the expression and function of VEGF-A and VEGF-C in the kidney. The current immunoregulation mechanisms of VEGF signaling pathway inhibitors are reviewed. Finally, combinate strategies are summarized to highlight the proposal for VEGF signaling pathway inhibitors.

A Plasma Exosomal Metabolic Profiling of Nonalcoholic Fatty Liver Disease Patients Complicated with Impaired Fasting Glucose.

BACKGROUND/AIMS: Nonalcoholic fatty liver disease is considered as the hepatic manifestation of metabolic syndrome. Detection of circulating exosomes together with metabolomic analysis of their cargo would provide early signals for metabolic derangements and complications associated with nonalcoholic fatty liver disease. Therefore, this study profiled exosomal metabolome of patients with nonalcoholic fatty liver disease and impaired fasting glucose. MATERIALS AND METHODS: Plasma exosomes were extracted from nonalcoholic fatty liver disease patients with or without impaired fasting glucose through differential ultracentrifugation. Their metabolite profiles were examined by ultrahigh-performance liquid chrom atography-quadrupole time-of-flight mass spectrometry. Pathway analysis was carried out on platform MetaboAnalyst 4.0. RESULTS: Thirty-nine patients were enrolled, including nonalcoholic fatty liver disease-alone group (n = 26) and age-and gender-comparable nonalcoholic fatty liver disease plus impaired fasting glucose group (n = 13). Although less than and different from their plasma counterparts, a total of 10 significantly differential exosomal metabolites were identified. Nonalcoholic fatty liver disease plus impaired fasting glucose group had higher concentrations of linoleic acid, palmitamide, stearamide, and oleamide, as well as a lower concentration of phosphatidylethanolamine [20:5(5Z,8Z,11Z,14Z,17Z)/20:5(5Z,8Z,11Z,14Z,17Z)]. Pathway analysis showed an obviously changed metabolism of linoleic acid. CONCLUSIONS: Metabolomic analysis of plasma exosomes revealed a distinct change in fatty acids and related pathways in nonalcoholic fatty liver disease patients with impaired fasting glucose. These preliminary results provide a metabolomic snapshot and basis for further investigation of exosome biology for these patients.

The effect of an information intervention on the career commitment of medical students: evidence from a randomized experiment.

Introduction: The needs-based shortage of healthcare workers is severe worldwide and it would be exacerbated if many medical students switch to other careers after graduation. Maintaining and improving the career commitment of medical students, which could be a feasible, effective, and scalable way to reduce the attrition rate, is essential in medical education. We designed a randomized experiment to test whether an information intervention based on role modeling could enhance medical students' career commitment. Methods: In the randomized experiment, the sample (N = 36,482) was divided into the treatment group (N = 18,070) and the control group (N = 18,412). The intervention information consisted of image-text messages on Zhong Nanshan, who is an inspiring role model for he went to the frontline of COVID-19 in the most critical circumstances and received praise and affirmation from the public. Α difference-in-differences model was employed to identify the effect of the information intervention. Heterogeneous treatment effects were identified using sub-sample analyses. Results: The results showed that the information intervention statistically significantly reduced medical students' dropout intention by 2.7 percentage points (95% CI: -0.037 to -0.016, t = -4.95, p < 0.001), equivalent to 14.6% of the control group mean. This estimate indicates that the information intervention could significantly increase the career commitment of medical students. Finally, male and senior students were influenced more than their female and junior counterparts, which can be explained by their relatively high dropout intention. Conclusion: Role model-based information intervention improves the career commitment of medical students. The underlying behavioral model is that, when students use a role model as their reference point, they consider dropout as a substantial welfare loss. Role modeling is an effective way to improve the career commitment of medical students, especially for males and senior students.

Metagenomic analysis reveals hidden links between gut microbes and habitat adaptation among cave and surface dwelling Sinocyclocheilus species.

Intestinal microbes are closely related to vital host functions such as digestion and nutrient absorption, which play important roles in enhancing host adaptability. As a natural "laboratory", caves provide an outstanding model for understanding the significance of gut microbes and feeding habits in the habitat adaptability of hosts. However, research on the relationship between gut microbes, feeding habits, and the adaptability of troglobites remains insufficient. In this study, we compared the characteristics of the intestinal microbes of Sinocyclocheilus cavefish and surface fish and further established the relationship between intestinal and habitat microbes. Furthermore, we conducted environmental DNA (eDNA) (metabarcoding) analysis of environmental samples to clarify the composition of potential food resources in the habitats of the Sinocyclocheilus cavefish and surface fish. Results showed that the structure of the Sinocyclocheilus gut microbes was more related to ecological type (habitat type) than phylogenetic relationships. While horizontal transfer of habitat microbes was a source of gut microbes, hosts also showed strong selection for inherent microbes as dominant microorganisms. Differences in the composition and structure of gut microbes, especially dominant microbes, may enhance the adaptability of the two Sinocyclocheilus fish types from the perspectives of food intake, nutrient utilization, and harmful substance metabolism, suggesting that food resources, predation patterns, intestinal flora, digestive and absorptive capacity, and feeding habits and preferences are linked to habitat adaptability. These results should facilitate our understanding of the significance of fish gut microbes to habitat adaptation and provide a new perspective for studying the adaptive mechanisms of cavefish.

Genome-Wide DNA Methylation Differences between Bos indicus and Bos taurus.

Disease risk is a persistent problem in domestic cattle farming, while economic traits are the main concern. This study aimed to reveal the epigenetic basis for differences between zebu (Bos indicus) and taurine cattle (Bos taurus) in disease, disease resistance, and economic traits, and provide a theoretical basis for the genetic improvement of domestic cattle. In this study, whole genome bisulfite sequencing (WGBS) was used to analyze the whole-genome methylation of spleen and liver samples from Yunnan zebu and Holstein cattle. In the genome-wide methylation pattern analysis, it was found that the methylation pattern of all samples was dominated by the CG type, which accounted for >94.9%. The DNA methylation levels of different functional regions and transcriptional elements in the CG background varied widely. However, the methylation levels of different samples in the same functional regions or transcriptional elements did not differ significantly. In addition, we identified a large number of differentially methylation region (DMR) in both the spleen and liver groups, of which 4713 and 4663 were annotated to functional elements, and most of them were annotated to the intronic and exonic regions of genes. GO and KEGG functional analysis of the same differentially methylation region (DMG) in the spleen and liver groups revealed that significantly enriched pathways were involved in neurological, disease, and growth functions. As a result of the results of DMR localization, we screened six genes (DNM3, INPP4B, PLD, PCYT1B, KCNN2, and SLIT3) that were tissue-specific candidates for economic traits, disease, and disease resistance in Yunnan zebu. In this study, DNA methylation was used to construct links between genotypes and phenotypes in domestic cattle, providing useful information for further screening of epigenetic molecular markers in zebu and taurine cattle.

Comparison of two frailty indices in predicting life-threatening morbidity and mortality among older patients undergoing elective high-risk abdominal surgery.

Background: Frailty predicts an increased risk of postoperative morbidity and mortality. Comparison of the predictive performance between two deficit accumulation models of frailty, the modified frailty index (mFI) and the revised-Risk Analysis Index (RAI-rev), is poorly understood. This study compared the predictive abilities of the above two frailty indices in predicting life-threatening morbidity and mortality among older patients following elective high-risk abdominal surgery. Methods: This retrospective cohort study extracted perioperative data of older patients (age ≥65 years) undergoing elective high-risk abdominal surgery at a single institution between January 2018 and December 2020. Preoperative frailty was screened by mFI and RAI-rev scoring systems. The primary outcome was the composite of postoperative life-threatening morbidity and mortality during hospitalization. Multivariable logistic regression analyses were performed to investigate the association of the two frailty indices with the primary outcome. Receiver-operating characteristic (ROC) curve was employed to test the predictive performances of the two frailty instruments in predicting the composite primary outcome. The difference between the area under the curves (AUCs) was assessed by DeLong's test. Results: 1,132 older patients (mean age, 73.4 ± 6.2 years; 63.9% male) were included. Of these, 107 (9.5%) developed postoperative life-threatening morbidity and mortality. In multivariable logistic regression analyses, rising continuous frailty scores (mFI: adjusted OR 1.319 per 0.09-point increase in score, 95% CI 1.151-1.511, p < 0.001; RAI-rev: adjusted OR 1.052 per 1-point increase in score, 95% CI 1.018-1.087, p = 0.002) as well as dichotomized frailty measures (mFI ≥0.27: adjusted OR 2.059, 95% CI 1.328-3.193, p = 0.001; RAI-rev ≥45: adjusted OR 1.862, 95% CI 1.188-2.919, p = 0.007) were associated with increased odds of the primary outcome separately. ROC curve analysis showed that the discrimination of mFI and RAI-rev scores for the life-threatening morbidity and mortality was poor and comparable (AUC: 0.598 [95% CI 0.569-0.627] vs. 0.613 [95% CI 0.583-0.641]; DeLong's test: Z = 0.375, p = 0.7075). Conclusion: High mFI and RAI-rev scores were associated with an increased risk of life-threatening morbidity and mortality in older patients undergoing elective high-risk abdominal surgery. However, both frailty indices displayed poor discrimination for postoperative life-threatening morbidity and mortality.

Birth-and-death evolution of ribonuclease 9 genes in Cetartiodactyla.

RNase9 plays a reproductive function and has been recognized as an important member of the ribonuclease (RNase) A superfamily, a gene family that is widely used as a model for molecular evolutionary studies. Here, we identified 178 RNase9 genes from 95 Cetartiodactyla species that represent all four lineages and 21 families of this clade. Unexpectedly, RNase9 experienced an evolutionary scenario of "birth and death" in Ruminantia, and expression analyses showed that duplicated RNase9A and RNase9B genes are expressed in reproductive tissues (epididymis, vas deferens or prostate). This expression pattern combined with the estimate that these genes duplicated during the middle Eocene, a time when Ruminantia become a successful lineage, suggests that the RNase9 gene duplication might have been advantageous for promoting sperm motility and male fertility as an adaptation to climate seasonality changes of this period. In contrast, all RNase9 genes were lost in the Cetacean lineage, which might be associated with their high levels of prostatic lesions and lower reproductive rates as adaptations to a fully aquatic environment and a balance to the demands of ocean resources. This study reveals a complex and intriguing evolutionary history and functional divergence for RNase9 in Cetartiodactyla, providing new insights into the evolution of the RNaseA superfamily and molecular mechanisms for organismal adaptations to the environment.

The Effects of Diatomite as an Additive on the Macroscopic Properties and Microstructure of Concrete.

Diatomite is a siliceous sedimentary rock containing amorphous silica, which can be used as a green mineral admixture to improve the properties of concrete. This study investigates the affecting mechanism of diatomite on concrete performance by macro and micro tests. The results indicate that diatomite can reduce the fluidity of concrete mixture and change its water absorption, compressive strength, resistance to chloride penetration (RCP), porosity, and microstructure. The low fluidity of concrete mixture containing diatomite can reduce workability. With increasing diatomite as partial replacement for cement in concrete, water absorption of concrete decreases before increasing, while compressive strength and RCP rise first and then drop. When diatomite is added to the cement at a content of 5% by weight, the concrete has the lowest water absorption and the highest compressive strength and RCP. Through the mercury intrusion porosimetry (MIP) test, we determined that the addition of 5% diatomite reduces the porosity of concrete from 12.68% to 10.82% and changes the proportion of pores with different sizes in concrete, the proportion of harmless and less harmful pores increases, and the proportion of harmful pores reduces. Based on the microstructure analysis, the SiO2 in diatomite can react with CH and produce C-S-H. C-S-H is responsible for developing concrete because it fills pores and cracks, forms a platy structure, and makes the concrete much denser, thereby improving its macroscopic performance and microstructure.