Osteoporosis (OP) is a common metabolic bone disease characterized by low bone mass and microstructural deterioration of bone. Changes in the composition and structure of gut microbiota (GM) are related to changes of bone mass and bone microstructure. However, the relationship between GM and bone mineral density (BMD) is complex, and data are especially scarce for Chinese Han youth. Therefore, 62 Chinese Han youth participants were recruited. Furthermore, according to the T–score evaluation criteria of the World Health Organization (WHO), we divided the BMD levels of participants into three groups: osteoporosis\BDL, osteopenia\BDM, normal bone density\BDH, and the associations between GM community and BMD groups were conducted. According to alpha and beta diversity analysis, significant differences were found in the microbial richness and composition between groups. The dominant phyla of GM in a cohort of Chinese Han youth were Bacteroidota (50.6%) and Firmicutes (41.6%). Anaerobic microorganisms, such as g_Faecalibacterium and g_Megamonas, account for the largest proportion in the gut, which were mainly Firmicutes phylum. The dominant genera and species in the three BMD groups were g_Prevotella, g_Bacteroides, g_Faecalibacterium, g_Megamonas, s_Prevotella copri, s_unclassified_g_Faecalibacterium, s_unclassified_g_Prevotella, s_unclassified_g_Bacteroides and s_Bacteroides plebeius. g_Faecalibacterium, g_Bacteroides and g_Ruminococcus differed between the BDH and BDL groups as well as between the BDH and BDM groups. LEfSe showed three genus communities and eight species communities were enriched in the three BMD groups, respectively. The associations between microbial relative abundance and T–score was not statistically significant by Spearman and regression analysis. In conclusion, the alpha diversity indexes in the BDH group were higher than in the BDL group, and several taxa were identified that may be the targets for diagnosis and therapy of OP.

Litter nutrient stoichiometry and its drivers are important for understanding nutrient cycling in desert ecosystems, plant adaptation strategies, and the sustainability of ecosystem functions. However, little is known about the spatial variation in litter nutrient stoichiometry and its environmental drivers in desert shrubs. This study focused on two Nitraria species (N. tangutorum Bobrov and N. sphaerocarpa Maxim) in Northwestern China, analyzing leaf litter N, P, and K stoichiometry, their spatial variation, and environmental drivers. Nutrient concentrations and stoichiometric ratios did not differ significantly between the two species. The average N contents in the litters of N. tangutorum and N. sphaerocarpa were 11.363 mg g⁻¹ and 11.295 mg g⁻¹, respectively. The P contents were 0.591 mg g⁻¹ and 0.611 mg g⁻¹, whereas the K contents were 17.482 mg g⁻¹ and 16.255 mg g⁻¹, respectively. With the changes in geographic and climatic factors, the same nutrient elements of the two Nitraria species showed inconsistent variation patterns. Both species showed low P concentration, indicating high P resorption and possible P limitation, reflecting nutrient vulnerability in desert ecosystems according to the scaling exponents among elements. In litter, the residual nutrient contents ranked as K > P > N, suggesting strong N resorption but low K resorption, especially for N. sphaerocarpa. N was mainly influenced by latitude, P by soil properties, and K by mean annual temperature. Moreover, litter stoichiometric ratios of N. tangutorum were relatively stable, whereas those of N. sphaerocarpa were more sensitive to environmental variables. In conclusion, the two Nitraria shrubs exhibited differential nutrient use strategies under nutrient restriction, providing insights into nutrient cycling and supporting sustainable management of desert ecosystems.

The rhizosphere microbial community of plants has a crucial effect on healthy plant growth, and each rhizosphere has a specific microbial community. C. sinensis cv. Shifocui is a tea plant distributed in the Dabie Mountains of Anhui Province. It has the characteristics of high yield, good quality, strong cold resistance, and a high amino acid content. This study was the first to use 16S rRNA high-throughput sequencing technology and bioinformatics methods to explore the characteristics and functions of the rhizosphere bacterial community of the cold-tolerant tea tree C. sinensis cv. Shifocui, providing an important basis for the development and utilization of rhizosphere microbial resources. The dominant phylum in the rhizosphere microbes of the C.sinensiscv. Shifocui rhizosphere microorganisms were Proteobacteria, Chloroflexi, Acidobacteriota, and Actinobacteria. Network analysis showed significant positive and negative correlations among the rhizosphere bacterial groups of C.sinensiscv. Shifocui, among which Candidatus_Xiphinematobacter, Acidobacteriale, Bradyrhizobium, Subgroup_2, Candidatus_Udaeobacter, Gemmataceae, and Gaiellales were notable nodes in the interaction networks. Functional prediction of FAPROTAX indicated that C. sinensis cv. Shifocui was rich in chemoheterotrophic, cellulose hydrolysis, and oxidative heterotrophic conditions, indicating that the dominant bacterial flora was enriched in its rhizosphere microbes and played an important role in plant growth and development.These results lay a foundation for exploring the mechanism of interaction between C.sinensiscv. Shifocui and rhizosphere microorganisms and provide a research basis for the development and utilization of tea plant microbial resources.

Background: One of the recognized effects of systematic physical activity is the improvement of physical fitness, with a negative correlation found between physical fitness and cardiovascular and cardiometabolic risk. The purpose of this study is to analyze the influence of single nucleotide polymorphisms (SNPs) of the adenylate cyclase 3 (ADCY3) gene on the effect of high-intensity interval training (HIIT) on blood lipids, and simultaneously screen out the genetic markers sensitive to HIIT in Chinese Han youth. Methods: In the 12-week HIIT program, a total of 237 Chinese Han college students with non-regular exercise habits were recruited, and these volunteers participated in the training three times a week. Baseline and after the HIIT program, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were measured, respectively. DNA was extracted from the white blood cells of volunteers and genotyping was carried out. The PLINK v1.09 software was used to conduct quality control screening on the obtained SNPs, and a linear regression model was constructed to analyze the association between ADCY3 gene SNPs and the effect of HIIT on blood lipids. ANOVA multiple comparison (LSD) was performed to test the difference between groups (P < 0.05). Results: (1) Through the analysis of Illumina CGA chip scanning, a total of 22 SNPs of the ADCY3 gene were identified. Following rigorous quality control screening, 15 SNPs were included in the subsequent analysis. Notably, it was found that the rs2241759 locus is associated with the effect of HIIT on blood lipid profiles. (2) Among male volunteers, significant differences in the baseline HDL-C values were observed among the three genotypes at the rs2241759 locus of the ADCY3 gene (β = − 0.019, P = 0.040). The baseline value for the GG genotype was higher than that AA/AG genotypes. (3) After HIIT, the total levels of TC and HDL-C in volunteers increased significantly (P < 0.05). In contrast, the total levels of TG and LDL-C decreased significantly (P < 0.05). Further statistical analysis categorized by gender revealed that, with the exception of TC values in men, significant changes were observed for TC, TG, HDL-C, and LDL-C across both genders (P < 0.05). (4) Compared to male volunteers with the GG genotype, male volunteers carrying the A allele exhibited a more pronounced change in TC values following training (β = 0.044, P = 0.038). (5) The rs2241759 locus demonstrated a significant association with the effect of HIIT on LDL-C (β = − 0.065, P = 0.04363). Conclusion: (1) The implementation of a 12-week HIIT regimen can significantly enhance the blood lipid status of college students. (2) The locus rs2241759 of the ADCY3 gene is significantly associated with the sensitivity of LDL-C to HIIT.

C. spectabilis (Crotalaria spectabilis), a large leguminous herb species, is widely distributed in tropical and subtropical regions, and it has important ecological and economic values. However, the ecological adaptation of the major leaf functional traits of the species across different habitats and canopy positions remains poorly understood. To address this gap, we sampled leaves from the upper, middle, and lower canopy positions in two common habitats—forest understory and exposed land—and quantified key leaf traits as well as trait–trait relationships to assess differences. The results showed that irradiance and air temperature were significantly lower in the understory than in exposed land, whereas soil moisture and relative humidity were higher, indicating that habitat exerted a stronger influence on leaf traits than canopy position. Canopy position also significantly affected most traits and showed significant interactions with habitat. In exposed land, middle plants exhibited higher individual leaf dry mass (180.049 ± 68.480 mg), larger vein diameter (1.692 ± 0.288 mm), and longer petioles (5.406 ± 0.940 mm). These traits were accompanied by a higher morphology-based leaf dry matter accumulation rate and greater stability of the leaf-trait network, reflecting an adaptive strategy characterized by increased structural investment. In contrast, understory middle leaves were generally longer (13.361 ± 2.714 cm) and wider (7.005 ± 1.464 cm), along with lower photosynthate accumulation rates and weaker trait-network stability, indicating a strategy that enhances light-use efficiency under low-light conditions. In both habitats, leaves from the middle canopy position generally exhibited the highest values for most measured traits. Overall, leaf traits of C. spectabilis and their interrelationships showed considerable plasticity in response to external environmental pressures, primarily differences in light availability. However, from a practical production perspective, minimizing shading is recommended to maximize its ecological benefits.