BACKGROUND:The mechanism of programmed death receptor-1(PD-1)effect on osteogenic differentiation of bone marrow mesenchymal stem cells in high glucose environment remains unclear. OBJECTIVE:To explore the effect of PD-1 on osteogenic differentiation of rat bone marrow mesenchymal stem cells in high glucose environment and its regulatory mechanism. METHODS:Rat bone marrow mesenchymal stem cells were randomly divided into normal glucose group(5.6 mmol/L),high glucose group(30 mmol/L),PD-1 overexpression group,PD-1 overexpression no-load group,PD-1 knockdown group,PD-1 knockdown no-load group,and PI3K/AKT pathway inhibitor group(PD-1 knockdown+5 μmol/L LY294002).Rat bone marrow mesenchymal stem cells were cultured in high glucose to simulate the diabetic environment in vitro.The mRNA expression of PD-1 and ligand PD-L1 and the mRNA expression of osteogenic markers Runx2 and OSX in rat bone marrow mesenchymal stem cells were detected by qRT-PCR.The osteogenic differentiation ability was observed by alkaline phosphatase staining and alizarin red staining.Cell proliferation was detected by CCK-8 assay.The protein expressions of PD-1,PD-L1,p-PI3K,and p-AKT were detected by western blot assay. RESULTS AND CONCLUSION:(1)The levels of PD-1 and PD-L1 were significantly increased in the high glucose environment in vitro,and the osteogenic differentiation ability of bone marrow mesenchymal stem cells was inhibited in the high glucose environment.(2)Knockdown of PD-1 expression could promote osteogenic differentiation of bone marrow mesenchymal stem cells,increase cell proliferation activity,and activate the PI3K/AKT pathway.(3)After addition of PI3K/AKT pathway inhibitor LY294002,the ability of bone marrow mesenchymal stem cells to differentiate into osteoblasts decreased.The results show that PD-1 is dependent on the PI3K/AKT signaling pathway to inhibit osteogenic differentiation of rat bone marrow mesenchymal stem cells under high glucose environment.

BACKGROUND:Traditional methods of urinary tract reconstruction are limited by donor scarcity,high complication rates,and suboptimal functional recovery.Tissue engineering strategies offer new directions in this field.Since the urinary tract is mainly composed of muscle tissue,the key is to find suitable seed cells and efficiently induce them to differentiate into smooth muscle cells.Comparative studies on the efficacy of different smooth muscle cell induction regimens are still lacking. OBJECTIVE:To isolate,culture,and identify human urine-derived stem cells,and to compare the effects of two different induction protocols. METHODS:Human urine-derived stem cells were isolated from urine samples of 11 healthy adult volunteers by multiple centrifugations.Surface markers were identified by flow cytometry.The multi-directional differentiation potential of human urine-derived stem cells was verified through osteogenic and adipogenic differentiation.Differentiation was induced by transforming growth factor-β1 or transforming growth factor-β1 combined with platelet derived growth factor for 14 days.Immunofluorescence staining and western blot assay were employed to compare the expression differences of smooth muscle-specific proteins(α-SMA and SM22). RESULTS AND CONCLUSION:(1)Urine-derived stem cells were successfully isolated from the eight urine samples of healthy people.These cells exhibit a"rice grain"-like morphology and possess a robust proliferative capacity.(2)Urine-derived stem cells exhibited high expression of mesenchymal stem cell surface markers(CD73,CD90,and CD44)and extremely low expression of hematopoietic stem cell surface markers(CD34 and CD45).These cells did not express CD19,CD105,and HLA-DR.(3)After osteogenic and adipogenic differentiation,the formation of calcium nodules and lipid droplets was observed,with positive staining results from Alizarin Red S and Oil Red O staining.(4)After 14 days of smooth muscle induction culture,immunofluorescence staining revealed that the smooth muscle differentiation rate of urine-derived stem cells treated with a combination of transforming growth factor-β1 and platelet derived growth factor was significantly higher compared to those treated with transforming growth factor-β1 alone(P<0.005).(5)After 14 days of smooth muscle induction culture,western blot assay further demonstrated that the expression levels of α-SMA and SM22 in the transforming growth factor-β1/platelet derived growth factor group were significantly elevated compared to those in the transforming growth factor-β1 only group(P<0.005).These findings confirm that urine-derived stem cells can be non-invasively isolated using multiple rounds of centrifugation.Compared with transforming growth factor-β1 alone,the combination of transforming growth factor-β1 and platelet derived growth factor can improve the efficiency of inducing urine-derived stem cells to differentiate into smooth muscle cells.

Objective To explore the accuracy of machine learning algorithms based on SHOX2 and RASSF1A methylation levels in predicting early-stage lung adenocarcinoma pathological types. Methods A retrospective analysis was conducted on formalin-fixed paraffin-embedded (FFPE) specimens from patients who underwent lung tumor resection surgery at Affiliated Hospital of Nantong University from January 2021 to January 2023. Based on the pathological classification of the tumors, patients were divided into three groups: a benign tumor/adenocarcinoma in situ (BT/AIS) group, a minimally invasive adenocarcinoma (MIA) group, and an invasive adenocarcinoma (IA) group. The methylation levels of SHOX2 and RASSF1A in FFPE specimens were measured using the LungMe kit through methylation-specific PCR (MS-PCR). Using the methylation levels of SHOX2 and RASSF1A as predictive variables, various machine learning algorithms (including logistic regression, XGBoost, random forest, and naive Bayes) were employed to predict different lung adenocarcinoma pathological types. Results A total of 272 patients were included. The average ages of patients in the BT/AIS, MIA, and IA groups were 57.97, 61.31, and 63.84 years, respectively. The proportions of female patients were 55.38%, 61.11%, and 61.36%, respectively. In the early-stage lung adenocarcinoma prediction model established based on SHOX2 and RASSF1A methylation levels, the random forest and XGBoost models performed well in predicting each pathological type. The C-statistics of the random forest model for the BT/AIS, MIA, and IA groups were 0.71, 0.72, and 0.78, respectively. The C-statistics of the XGBoost model for the BT/AIS, MIA, and IA groups were 0.70, 0.75, and 0.77, respectively. The naive Bayes model only showed robust performance in the IA group, with a C-statistic of 0.73, indicating some predictive ability. The logistic regression model performed the worst among all groups, showing no predictive ability for any group. Through decision curve analysis, the random forest model demonstrated higher net benefit in predicting BT/AIS and MIA pathological types, indicating its potential value in clinical application. Conclusion Machine learning algorithms based on SHOX2 and RASSF1A methylation levels have high accuracy in predicting early-stage lung adenocarcinoma pathological types.

Background The decline of physical activity in the elderly due to aging may increase the risk of sarcopenia. Currently, there is a lack of evidence from large natural populations on the relationship between PA and sarcopenia. Objective To explore the relationship between PA and sarcopenia in the elderly aged 60 years and above in 10 provinces (autonomous regions) of China. Methods Data were retrieved from the 2022—2023 round of the China Development and Nutrition Health Impact Cohort. Personal basic information and PA data were collected by questionnaire survey. Skeletal muscle mass was measured by bio-electrical impedance analysis, muscle strength was measured using a grip dynamometer, and physical performance was reflected by 6-meter walk speed. The Asian Working Group for Sarcopenia (AWGS) 2019 criteria were used to diagnose sarcopenia. Light physical activity (LPA) duration, moderate-to-vigorous physical activity (MVPA) duration, and total physical activity volume were calculated. A total of 3326 residents aged ≥60 years with complete data were selected as the survey participants. Multiple logistic regression models and restricted cubic splines (RCS) were used to assess the association between PA duration/volume and sarcopenia. Results In 10 provinces (autonomous regions) of China, the prevalence of sarcopenia in the elderly aged 60 years and above was 5.5% (95%CI: 4.7%, 6.2%). The logistic regression analysis showed that compared with the elderly reporting 0-7.0 h·week⁻¹ in LPA duration, the risk of sarcopenia in the elderly with LPA duration of >14.0-21.0 h·week⁻¹ was reduced by 51% (OR=0.49, 95%CI: 0.26, 0.96). Compared with the elderly with total physical activity ≥15.0 metabolic equivalent of task (MET)-h·week⁻¹, those with <7.5 MET-h·week⁻¹ had a 2.24-fold increased risk of sarcopenia (OR=2.24, 95%CI: 1.17, 4.29). The RCS results found that LPA duration and total physical activity volume each showed a nonlinear dose-response relationship with the risk of sarcopenia (P_overall<0.05, P_non-linear<0.05). Compared with the elderly with an LPA duration of 0 h· week⁻¹, the risk of sarcopenia in the elderly with an LPA duration of 12.6 h· week⁻¹ was the lowest (OR=0.42, 95%CI: 0.21, 0.83). Compared with the elderly with a total physical activity volume of 15.0 MET-h· week⁻¹, the elderly with a total physical activity volume of 46.0 MET-h· week⁻¹ had the lowest risk of sarcopenia (OR=0.57, 95%CI: 0.38, 0.84). There was no statistically significant association between weekly MVPA duration and the risk of sarcopenia (P>0.05). Conclusion Increasing weekly LPA duration and total physical activity volume would help to reduce the risk of sarcopenia.

BACKGROUND: The level of measurable residual disease (MRD) before and after transplantation is related to inferior transplant outcomes, and post-hematopoietic stem cell transplantation measurable residual disease (post-HSCT MRD) has higher prognostic value in determining risk than pre-hematopoietic stem cell transplantation measurable residual disease (pre-HSCT MRD). However, only a few work has been devoted to the risk factors for positive post-HSCT MRD in patients with acute lymphoblastic leukemia (ALL). This study evaluated the risk factors for post-HSCT MRD positivity in patients with ALL who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: A total of 1683 ALL patients from Peking University People's Hospital between January 2009 and December 2019 were enrolled to evaluate the cumulative incidence of post-HSCT MRD. Cox proportional hazard regression models were built for time-to-event outcomes. Multivariable analysis was performed to determine independent influencing factors from the univariable analysis. RESULTS: Both in total patients and in T-cell ALL or B-cell ALL, pediatric or adult, human leukocyte antigen-matched sibling donor transplantation or haploidentical SCT subgroups, positive pre-HSCT MRD was a risk factor for post-HSCT MRD positivity ( P  <0.001 for all). Disease status (complete remission 1 [CR1] vs . ≥CR2) was also a risk factor for post-HSCT MRD positivity in all patients and in the B cell-ALL, pediatric, or haploidentical SCT subgroups ( P  = 0.027; P  = 0.003; P  = 0.035; P  = 0.003, respectively). A risk score for post-HSCT MRD positivity was developed using the variables pre-HSCT MRD and disease status. The cumulative incidence of post-HSCT MRD positivity was 12.3%, 25.1%, and 38.8% for subjects with scores of 0, 1, and 2-3, respectively ( P  <0.001). Multivariable analysis confirmed the association of the risk score with the cumulative incidence of post-HSCT MRD positivity and relapse as well as leukemia-free survival and overall survival. CONCLUSION Our results indicated that positive pre-MRD and disease status were two independent risk factors for post-HSCT MRD positivity in patients with ALL who underwent allo-HSCT.
Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology* ; Neoplasm, Residual ; Hematopoietic Stem Cell Transplantation/methods* ; Male ; Female ; Risk Factors ; Adolescent ; Adult ; Child ; Child, Preschool ; Young Adult ; Middle Aged ; Infant ; Transplantation, Homologous ; Proportional Hazards Models ; Retrospective Studies

Microbial communities such as those residing in the human gut are highly diverse and complex, and many with important implications for health and diseases. The effects and functions of these microbial communities are determined not only by their species compositions and diversities but also by the dynamic intra- and inter-cellular states at the transcriptional level. Powerful and scalable technologies capable of acquiring single-microbe-resolution RNA sequencing information in order to achieve a comprehensive understanding of complex microbial communities together with their hosts are therefore utterly needed. Here we report the development and utilization of a droplet-based smRNA-seq (single-microbe RNA sequencing) method capable of identifying large species varieties in human samples, which we name smRandom-seq2. Together with a triple-module computational pipeline designed for the bacteria and bacteriophage sequencing data by smRandom-seq2 in four human gut samples, we established a single-cell level bacterial transcriptional landscape of human gut microbiome, which included 29,742 single microbes and 329 unique species. Distinct adaptive response states among species in Prevotella and Roseburia genera and intrinsic adaptive strategy heterogeneity in Phascolarctobacterium succinatutens were uncovered. Additionally, we identified hundreds of novel host-phage transcriptional activity associations in the human gut microbiome. Our results indicated that smRandom-seq2 is a high-throughput and high-resolution smRNA-seq technique that is highly adaptable to complex microbial communities in real-world situations and promises new perspectives in the understanding of human microbiomes.
Humans ; Gastrointestinal Microbiome/genetics* ; Bacteriophages/physiology* ; High-Throughput Nucleotide Sequencing ; Sequence Analysis, RNA/methods* ; Bacteria/virology*

The Split-Cre system consists of two inactive polypeptides: NCre and CCre, which can be recombined into an active full-length Cre under certain conditions. This system is typically used with LoxP. To develop an efficient Split-Cre system, this study used Rma intein from Rhodothermus marinus to split Cre and screened out the split site S102 which could efficiently mediate the recombination of Cre in the "Traffic Light" reporter cell line. Moreover, the S102 Split-Cre system was delivered to mice by dual-adeno-associated virus (AAV), and it was demonstrated that the efficiency of the Rma intein-mediated S102 Split-Cre system was comparable to the full-length Cre in mice. This system lays a foundation for both basic and applied research on Split-Cre.
Inteins/genetics* ; Animals ; Integrases/biosynthesis* ; Mice ; Dependovirus/metabolism* ; Bacterial Proteins/genetics* ; Recombination, Genetic ; Humans

Sugarcane (Saccharum spp.) is an important sugar crop. Biotic and abiotic stresses such as diseases, cold, and drought are major factors limiting sugarcane production. β-1,3-glucanase (EC 3.2.1.39), a member of the pathogenesis-related protein family, plays an essential role not only in the plant defenses against pathogens but also in plant growth, development, and abiotic stress responses. To systematically investigate the sugarcane β-1,3-glucanase gene family, 132 glycoside hydrolase (GH) 17 family members were identified in the genomes of the sugarcane wild species Saccharum spontaneum 'Np-X', the tropical species S. officinarum 'LA-Purple', and the Saccharum spp. hybrid cultivar 'R570'. The results of the phylogenetic analysis categorized them into four subfamilies, of which subfamily Ⅳ had the largest proportion of members (102). The members of the sugarcane GH17 gene family contained five conserved motifs and 0-16 introns. The majority of the GH17 genes exhibited a genome-wide replication pattern, with 89.50% originating from S. spontaneum 'Np-X' and S. officinarum 'LA-Purple', while 58.10% of them in the Saccharum spp. hybrid cultivar 'R570' belonged to the discrete replication type. Four major classes of cis-acting elements were identified in the promoters, including the elements related to plant growth, development, and tissue-specific expression (14.21%), light-responsive elements (38.24%), biotic or abiotic stress-responsive elements (9.18%), and hormone-responsive elements (38.37%), which suggested that this gene family was involved in plant growth, development, hormone responses, and stress responses. Transcriptome and quantitative real-time PCR (RT-qPCR) analyses showed that the sugarcane GH17 genes exhibited tissue-specific expression and were differentially expressed under low temperature, drought, and hormone treatments, as well as during the interactions between different sugarcane genotypes and Sporisorium scitamineum, suggesting their potential roles in plant defenses. In addition, some SsGlu genes (SsGlu5, SsGlu20, SsGlu21, SsGlu25, SsGlu28, and SsGlu39) were expected to serve as candidate stress-related genes. This study lays a foundation for further revealing the molecular mechanisms of the stress resistance of sugarcane via β-1,3-glucanase genes.
Saccharum/physiology* ; Stress, Physiological/genetics* ; Glucan 1,3-beta-Glucosidase/metabolism* ; Multigene Family ; Phylogeny ; Gene Expression Regulation, Plant ; Plant Proteins/genetics*