Barrierless reactions of C2 Criegee intermediates with H2SO4 and their implication to oligomers and new particle formation.

The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol (SOA). However, to date, the reactivity of C2 Criegee intermediates (CH3CHOO) in areas contaminated with acidic gas remains poorly understood. Herein, high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations are used to explore the reaction of CH3CHOO and H2SO4 both in the gas phase and at the air-water interface. In the gas phase, the addition reaction of CH3CHOO with H2SO4 to generate CH3HC(OOH)OSO3H (HPES) is near-barrierless, regardless of the presence of water molecules. BOMD simulations show that the reaction at the air-water interface is even faster than that in the gas phase. Further calculations reveal that the HPES has a tendency to aggregate with sulfuric acids, ammonias, and water molecules to form stable clusters, meanwhile the oligomerization reaction of CH3CHOO with HPES in the gas phase is both thermochemically and kinetically favored. Also, it is noted that the interfacial HPES- ion can attract H2SO4, NH3, (COOH)2 and HNO3 for particle formation from the gas phase to the water surface. Thus, the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions, but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.

Serum biomarker-based risk model construction for primary Sjögren's syndrome with interstitial lung disease.

Background: Cytokine network disturbances in primary Sjögren's syndrome (pSS) have been reported in many studies. However, their functions in patients with primary Sjögren's syndrome and interstitial lung disease (pSS-ILD) is controversial. In this study, we aim to investigate the associations of immunological characteristics and cytokine profiles with pSS-ILD pathogenesis and explore their predictive values for pSS progression. Methods: A total of 256 patients initially diagnosed with pSS at Henan Provincial People's Hospital were enrolled. After excluding the patients previously diagnosed with various serious acute and chronic respiratory system diseases and cases with other connective tissue diseases or congenital heart diseases, 94 pSS patients were included for further analysis, including 40 patients with ILD (pSS-ILD) and 54 patients without ILD (pSS-N-ILD). For comparison, 41 age- and sex-matched healthy individuals were included as normal controls. Their clinical symptoms and serological data including cyclic citrullinated peptide (CCP) antibody (anti-CCP), antinuclear antibody (ANA), anti-Ro52, anti-SSA, anti-SSB, C-reactive protein, IgG, IgM, IgA, C3, C4, and 10 cytokines and chemokines were obtained. Wilcoxon test, chi-square test, Spearman correlation analysis, and logistics regression analysis were performed. Results: Higher positive rates of anti-SSB and higher incidence of dry cough, dyspnea, and arthrosis symptoms were shown in pSS-ILD patients than in the pSS-N-ILD cases. Anti-CCP antibodies and cytokines (IL-1ß, TNFα, IL-6, IL-5, IL-12p70, and IL-17) were higher, while C3 was lower in pSS-ILD patients than in pSS-N-ILD cases. Significant negative correlations of IgG with C3 and C4 and positive correlations of IL-12p70 and IL-17 with IL-6 were only shown in pSS-ILD patients. The anti-CCP antibody was positively correlated with IL-5 in pSS-ILD patients, but not in pSS-N-ILD cases. Multi-variable logistics regression analysis revealed the combination of anti-CCP, IL-17, IL-12p70, and IL-5 was effective in predicting the status of pSS-ILD in the pSS cases. Conclusion: There were significant differences in serum marker levels between pSS-ILD and pSS-N-ILD cases. The combination of anti-CCP, IL-17, IL-12p70, and IL-5 might be a potential risk predictor for pSS-ILD occurrence. The cytokines might be involved in the development and progression of pSS-ILD. These results would provide new therapeutic targets for pSS-ILD treatment.

Development of innovative multi-epitope mRNA vaccine against central nervous system tuberculosis using in silico approaches.

Tuberculosis(TB) of the Central nervous system (CNS) is a rare and highly destructive disease. The emergence of drug resistance has increased treatment difficulty, leaving the Bacillus Calmette-Guérin (BCG) vaccine as the only licensed preventative immunization available. This study focused on identifying the epitopes of PknD (Rv0931c) and Rv0986 from Mycobacterium tuberculosis(Mtb) strain H37Rv using an in silico method. The goal was to develop a therapeutic mRNA vaccine for preventing CNS TB. The vaccine was designed to be non-allergenic, non-toxic, and highly antigenic. Codon optimization was performed to ensure effective translation in the human host. Additionally, the secondary and tertiary structures of the vaccine were predicted, and molecular docking with TLR-4 was carried out. A molecular dynamics simulation confirmed the stability of the complex. The results indicate that the vaccine structure shows effectiveness. Overall, the constructed vaccine exhibits ideal physicochemical properties, immune response, and stability, laying a theoretical foundation for future laboratory experiments.

Design a novel of Brucellosis preventive vaccine based on IgV_CTLA-4 and multiple epitopes via immunoinformatics approach.

Brucellosis is a zoonotic disease caused by Brucella, which is difficult to eliminate by conventional drugs. Therefore, a novel multi-epitope vaccine (MEV) was designed to prevent human Brucella infection. Based on the method of "reverse vaccinology", cytotoxic T lymphocyte epitopes (CTLEs), helper T lymphocyte epitopes (HTLEs), linear B-cell epitopes (LBEs) and conformational B-cell epitopes (CBEs) of four Brucella proteins (VirB9, VirB10, Omp 19 and Omp 25) were obtained. In order to keep the correct protein folding, the multiple epitopes was constructed by connecting epitopes through linkers. In view of the significant connection between human leukocyte antigen CTLA-4 and B7 molecules found on antigen presenting cells (APCs), a new vaccine (V_C4MEV) for preventing brucellosis was created by combining CTLA-4 immunoglobulin variable region (IgV_CTLA-4) with MEV protein. Immunoinformatics analysis showed that V_C4MEV has a good secondary and tertiary structure. Additionally, molecular docking and molecular dynamics simulation (MD) revealed a robust binding affinity between IgV_ CTLA-4 and the B7 molecule. Notably, the vaccine V_C4MEV was demonstrated favorable immunogenicity and antigenicity in both in vitro and in vivo experiments. V_C4MEV had the potential to activate defensive cells and immune responses, offering a hopeful approach for developing vaccines against Brucella in the upcoming years.

Occurrence and potential diffusion of pine wilt disease mediated by insect vectors in China under climate change.

BACKGROUND: Pine wilt disease (PWD), a major international quarantined forest pest, causes serious ecological and economic damage to Pinus species in Asia and Europe. In China, PWD has spread northeasterly and northwesterly beyond its original northern limits. Consequently, an evaluation of the insect vector-mediated occurrence and potential diffusion of PWD is needed to identify important transmission routes and control the spread of disease. RESULTS: An optimized MaxEnt model was used to assess the current and future geographical distribution of Bursaphelenchus xylophilus and its insect vectors in China. The predicted suitable area for B. xylophilus colonization is currently 212.32 × 104 km2 and mainly concentrated in Central, East, Southwest and South China, although is anticipated to include the northwestern regions of China in the future. As for the insect vectors, Monochamus alternatus and M. saltuarius are expected to spread toward the northwest and southwest, respectively. The maximum predicted dispersion area of PWD mediated by M. alternatus, M. saltuarius and both species was 91.85 × 104, 218.76 × 104 and 29.99 × 104 km2, respectively, with potential diffusion areas being anticipated to increase in the future. Both the suitable probabilities and areas of B. xylophilus and its insect vectors were found to vary substantially along the latitudinal gradient, with the latitudinal range of these species being predicted to expand in the future. CONCLUSION: This is the first study to investigate the potential diffusion areas of PWD mediated by insect vectors in China, and our finding will provide a vital theoretical reference and empirical basis for developing more effective management strategies for the control of PWD in China. © 2024 Society of Chemical Industry.

Study on Thermophysical Properties and Phase Change Regulation Mechanism of Optically-Controlled Phase Change Materials: Synthesis, Crystal Structure and Molecular Dynamics.

Optically-controlled phase change materials, which are prepared by introducing molecular photoswitches into traditional phase change materials (PCMs), can convert and store solar energy into photochemical enthalpy and phase change enthalpy. However, the thermophysical properties of optically controlled PCMs, which are crucial in the practical, are rarely paid attention to. 4-(phenyldiazenyl)phenyl decanoate (Azo-A-10) is experimentally prepared as an optically-controlled PCMs, whose energy storage density is 210.0 kJ·kg-1, and the trans single crystal structure is obtained. The density, phase transition temperature, thermal conductivity, and other parameters in trans state are measured experimentally. Furthermore, a microscopic model of Azo-A-10 is established, and the thermophysical properties are analyzed based on molecular dynamics. The results show that the microstructure parameter (order parameters) and thermophysical properties (density, radial distribution function, self-diffusion coefficient, phase change temperature, and thermal conductivity) of partially or completely isomerized Azo-A-10, which are challenging to observe in experiments, can be predicted by molecular dynamics simulation. The optically-controlled phase change mechanism can be clarified according to the differences in microstructure. The optically-controlled switchability of thermophysical properties of an optically-controlled PCM is analyzed. This study provides ideas for the improvement, development, and application of optically-controlled PCMs in the future.

The nociceptive inputs of the paraventricular hypothalamic nucleus in formalin stimulated mice.

The paraventricular hypothalamic nucleus (PVH) is an important neuroendocrine center involved in pain regulation, but the nociceptive afferent routes for the nucleus are still unclear. We examined the profile of PVH receiving injurious information by a combination of retrograde tracing with Fluoro-Gold (FG) and FOS expression induced by formalin stimuli. The result showed that formalin injection induced significantly increased expression of FOS in the PVH, among which oxytocin containing neurons are one neuronal phenotype. Immunofluorescent staining of FG and FOS revealed that double labeled neurons were strikingly distributed in the area 2 of the cingulate cortex (Cg2), the lateral septal nucleus (LS), the periaqueductal gray (PAG), the posterior hypothalamic area (PH), and the lateral parabrachial nucleus (LPB). In the five regions, LPB had the biggest number and the highest ratio of FOS expression in FG labeled neurons, with main subnuclei distribution in the external, superior, dorsal, and central parts. Further immunofluorescent triple staining disclosed that about one third of FG and FOS double labeled neurons in the LPB were immunoreactive for calcitonin gene related peptide (CGRP). In conclusion, the present study demonstrates the nociceptive input profile of the PVH area under inflammatory pain and suggests that neurons in the LPB may play essential roles in transmitting noxious information to the PVH.

The development of a human Brucella mucosal vaccine: What should be considered?

Brucellosis is a chronic infectious disease that is zoonotic in nature. Brucella can infect humans through interactions with livestock, primarily via the digestive tract, respiratory tract, and oral cavity. This bacterium has the potential to be utilized as a biological weapon and is classified as a Category B pathogen by the Centers for Disease Control and Prevention. Currently, there is no approved vaccine for humans against Brucella, highlighting an urgent need for the development of a vaccine to mitigate the risks posed by this pathogen. Brucella primarily infects its host by adhering to and penetrating mucosal surfaces. Mucosal immunity plays a vital role in preventing local infections, clearing microorganisms from mucosal surfaces, and inhibiting the spread of pathogens. As mucosal vaccine strategies continue to evolve, the development of a safe and effective mucosal vaccine against Brucella appears promising.This paper reviews the immune mechanism of mucosal vaccines, the infection mechanism of Brucella, successful Brucella mucosal vaccines in animals, and mucosal adjuvants. Additionally, it elucidates targeting and optimization strategies for mucosal vaccines to facilitate the development of human vaccines against Brucella.

Development of a novel multi-epitope vaccine for brucellosis prevention.

Brucellosis, a zoonotic disease caused by Brucella, presents a significant threat to both animal and human health. In animals, the disease can lead to infertility, miscarriage, and high fever, while in humans, symptoms may include recurrent fever, fatigue, sweating, hepatosplenomegaly, and joint and muscle pain following infection. Treatment often involves long-term antibiotic therapy, placing a substantial psychological and financial burden on patients. While vaccination is crucial for prevention, current animal vaccines have drawbacks such as residual virulence, and a safe and effective human vaccine is lacking. Hence, the development of a vaccine for brucellosis is imperative. In this study, we utilized bioinformatics methods to design a multi-epitope vaccine targeting Brucella. Targeting Heme transporter BhuA and polysaccharide export protein, we identified antigenic epitopes, including six cytotoxic T lymphocyte (CTL) dominant epitopes, six helper T lymphocyte (HTL) dominant epitopes, one conformation B cell dominant epitope, and three linear B cell dominant epitopes. By linking these epitopes with appropriate linkers and incorporating a Toll-like receptor (TLR) agonist (human beta-defensin-2) and an auxiliary peptide (Pan HLA-DR epitopes), we constructed the multi-epitope vaccine (MEV). The MEV demonstrated high antigenicity, non-toxicity, non-allergenicity, non-human homology, stability, and solubility. Molecular docking analysis and molecular dynamics simulations confirmed the interaction and stability of the MEV with receptors (MHCI, MHCII, TLR4). Codon optimization and in silico cloning validated the translation efficiency and successful expression of MEV in Escherichia coli. Immunological simulations further demonstrated the efficacy of MEV in inducing robust immune responses. In conclusion, our findings suggest that the engineered MEVs have the potential to stimulate both humoral and cellular immune responses, offering valuable insights for the future development of safe and efficient Brucella vaccines.

Obesity-enriched gut microbe degrades myo-inositol and promotes lipid absorption.

Numerous studies have reported critical roles for the gut microbiota in obesity. However, the specific microbes that causally contribute to obesity and the underlying mechanisms remain undetermined. Here, we conducted shotgun metagenomic sequencing in a Chinese cohort of 631 obese subjects and 374 normal-weight controls and identified a Megamonas-dominated, enterotype-like cluster enriched in obese subjects. Among this cohort, the presence of Megamonas and polygenic risk exhibited an additive impact on obesity. Megamonas rupellensis possessed genes for myo-inositol degradation, as demonstrated in vitro and in vivo, and the addition of myo-inositol effectively inhibited fatty acid absorption in intestinal organoids. Furthermore, mice colonized with M. rupellensis or E. coli heterologously expressing the myo-inositol-degrading iolG gene exhibited enhanced intestinal lipid absorption, thereby leading to obesity. Altogether, our findings uncover roles for M. rupellensis as a myo-inositol degrader that enhances lipid absorption and obesity, suggesting potential strategies for future obesity management.

Universal subunit vaccine protects against multiple SARS-CoV-2 variants and SARS-CoV.

Although Omicron RBD of SARS-CoV-2 accumulates many mutations, the backbone region (truncated RBD) of spike protein is highly conserved. Here, we designed several subunit vaccines by keeping the conserved spike backbone region of SARS-CoV-2 Omicron BA.1 subvariant (S-6P-no-RBD), or inserting the RBD of Delta variant (S-6P-Delta-RBD), Omicron (BA.5) variant (S-6P-BA5-RBD), or ancestral SARS-CoV-2 (S-6P-WT-RBD) to the above backbone construct, and evaluated their ability to induce immune responses and cross-protective efficacy against various SARS-CoV-2 variants and SARS-CoV. Among the four subunit vaccines, S-6P-Delta-RBD protein elicited broad and potent neutralizing antibodies against all SARS-CoV-2 variants tested, including Alpha, Beta, Gamma, and Delta variants, the BA.1, BA.2, BA.2.75, BA.4.6, and BA.5 Omicron subvariants, and the ancestral strain of SARS-CoV-2. This vaccine prevented infection and replication of SARS-CoV-2 Omicron, and completely protected immunized mice against lethal challenge with the SARS-CoV-2 Delta variant and SARS-CoV. Sera from S-6P-Delta-RBD-immunized mice protected naive mice against challenge with the Delta variant, with significantly reduced viral titers and without pathological effects. Protection correlated positively with the serum neutralizing antibody titer. Overall, the designed vaccine has potential for development as a universal COVID-19 vaccine and/or a pan-sarbecovirus subunit vaccine that will prevent current and future outbreaks caused by SARS-CoV-2 variants and SARS-related CoVs.

CircATF6 inhibits hepatocellular carcinoma progression by suppressing calreticulin-mediated Wnt/ß-catenin signaling pathway.

Circular RNAs (circRNAs) are covalently closed, single-stranded RNAs that play critical roles in various biological processes and diseases, including cancers. However, the functions and mechanisms of circRNAs in hepatocellular carcinoma (HCC) need further clarification. Here, we identified and confirmed that circATF6 is downregulated in HCC tissues and negatively associated with the overall survival of HCC patients. Ectopic overexpression of circATF6 inhibits malignant phenotypes of HCC cells in vitro and in vivo, while knockdown of circATF6 had opposite effects. Mechanistically, we found that circATF6 bound to calreticulin (CALR) protein and acted as a scaffold to enhance the interaction of CALR with calpain2 (CAPN2), which promoted the degradation of CALR by its enzymatic activity. Moreover, we found that circATF6 inhibited HCC cells by suppressing CALR-mediated wnt/ß-catenin signaling pathway. Taken together, our findings suggest that circATF6 is a potential prognostic biomarker and therapeutic target for HCC.

Identification of novel dual-target 4-hydroxyphenylpyruvate dioxygenase & phytoene dehydrogenase inhibitors via multiple virtual screening.

Two important plant enzymes are 4-hydroxyphenylpyruvate dioxygenase (HPPD; EC 1.13.11.27), which is necessary for biosynthesis of plastoquinone and tocopherols, and phytoene dehydrogenase (PDS; EC 1.3.99.26), which plays an important role in colour rendering. Dual-target proteins that inhibit pigment synthesis will prevent resistant weeds and improve the spectral characteristics of herbicides. This study introduces virtual screening of pharmacophores based on the complex structure of the two targets. A three-dimensional database was established by screening 1,492,858 compounds based on the Lipinski principle. HPPD&PDS dual-target receptor-ligand pharmacophore models were then constructed, and nine potential dual-target inhibitors were obtained through pharmacophore modeling, molecular docking, and molecular dynamics simulations. Ultimately, ADMET prediction software yielded three compounds with high potential as dual-target herbicides. The obtained nine inhibitors were stable when combined with both HPPD and PDS proteins. This study offers guidance for the development of HPPD&PDS dual-target inhibitors with novel skeletons.

Association between subchorionic hematoma in the first trimester and outcomes of singleton pregnancies achieved through assisted reproductive technology: a systematic review and meta-analysis.

PURPOSE: To evaluate the association between first trimester (≤ 12 weeks gestation) subchorionic hemorrhage (SCH), and maternal and neonatal outcomes in women who conceived with the help of assisted reproductive technique (ART). METHODS: PubMed, Embase, Web of Science, and Scopus databases were searched for observational studies that specifically focused on women who achieved pregnancy via ART and investigated the relationship between early pregnancy (within 12 weeks of gestation) SCH and maternal and neonatal outcomes. Only studies with singleton pregnancies and reporting data on the comparator group (women without SCH) were included. Primary outcomes of interest included incidences of early (within 20 weeks of gestation) pregnancy loss, preterm delivery, caesarean section, and live birth rates. Pooled effect sizes were reported as odds ratio (OR) with 95% confidence intervals (CI). RESULTS: Nine studies were included. All studies had a cohort design. In all studies, the primary assisted reproduction technique used was in-vitro fertilization (IVF). Compared to pregnancies without SCH, women with diagnosed early pregnancy SCH have a similar risk of preterm birth (< 37 weeks) (OR 1.01, 95% CI 0.83, 1.22), low birth weight (< 2500 g) (OR 1.01, 95% CI 0.59, 1.73) and fetal growth restriction (OR 1.57, 95% CI 0.62, 4.02). The gestational age (in weeks) (weighted mean difference (WMD) - 0.06, 95% CI - 0.18, 0.06) and the birth weight (in grams) (WMD - 16.5, 95% CI - 62.9, 29.8) were also similar in the two groups. The odds of early pregnancy loss (OR 1.39, 95% CI 0.97, 2.01), live birth (OR 0.77, 95% CI 0.55, 1.08) and caesarean delivery (OR 0.97, 95% CI 0.81, 1.16) were statistically similar in both groups. The risk of maternal adverse outcomes such as gestational diabetes (OR 0.98, 95% CI 0.74, 1.29), hypertensive disorder (OR 0.95, 95% CI 0.63, 1.43), premature rupture of membranes (PROM) (OR 1.36, 95% CI 0.90, 2.05) and placental abruption (OR 2.44, 95% CI 0.57, 10.5) was also similar in both the groups. There was no evidence of publication bias. CONCLUSION: The findings suggest that SCH may not significantly increase the risk of adverse maternal and perinatal outcomes in pregnancies conceived through ART, particularly IVF. TRIAL REGISTRATION: PROSPERO registration number CRD42024533996.

Lipoprotein (a)-Related Inflammatory Imbalance: A Novel Horizon for the Development of Atherosclerosis.

PURPOSE OF REVIEW: The primary objective of this review is to explore the pathophysiological roles and clinical implications of lipoprotein(a) [Lp(a)] in the context of atherosclerotic cardiovascular disease (ASCVD). We seek to understand how Lp(a) contributes to inflammation and arteriosclerosis, aiming to provide new insights into the mechanisms of ASCVD progression. RECENT FINDINGS: Recent research highlights Lp(a) as an independent risk factor for ASCVD. Studies show that Lp(a) not only promotes the inflammatory processes but also interacts with various cellular components, leading to endothelial dysfunction and smooth muscle cell proliferation. The dual role of Lp(a) in both instigating and, under certain conditions, mitigating inflammation is particularly noteworthy. This review finds that Lp(a) plays a complex role in the development of ASCVD through its involvement in inflammatory pathways. The interplay between Lp(a) levels and inflammatory responses highlights its potential as a target for therapeutic intervention. These insights could pave the way for novel approaches in managing and preventing ASCVD, urging further investigation into Lp(a) as a therapeutic target.

Effectiveness and safety of tripterygium wilfordii poly-glycosides on glomerulonephritis: a systematic review and meta-analysis.

Treatment of glomerulonephritis presents several challenges, including limited therapeutic options, high costs, and potential adverse reactions. As a recognized Chinese patent medicine, Tripterygium wilfordii poly-glycosides (TWP) have shown promising benefits in managing autoimmune diseases. To evaluate clinical effectiveness and safety of TWP in treating glomerulonephritis, we systematically searched PubMed, Cochrane Library, Web of Science, and Embase databases for controlled studies published up to 12 July 2023. We employed weighted mean difference and relative risk to analyze continuous and dichotomous outcomes. This meta-analysis included 16 studies that included primary membranous nephropathy (PMN), type 2 diabetic kidney disease (DKD), and Henoch-Schönlein purpura nephritis (HSPN). Analysis revealed that additional TWP administration improved patients' outcomes and total remission rates, reduced 24-h urine protein (24hUP) and decreased relapse events. The pooled results demonstrated the non-inferiority of TWP to glucocorticoids in achieving total remission, reducing 24hUP, and converting the phospholipase A2 receptor (PLA2R) status to negative. For DKD patients, TWP effectively reduced 24hUP levels, although it did not significantly improve the estimated glomerular filtration rate (eGFR). Compared to valsartan, TWP showed comparable improvements in 24hUP and eGFR levels. In severe cases of HSPN in children, significant clinical remission and a reduction in 24hUP levels were observed with the addition of TWP treatment. TWP did not significantly increase the incidence of adverse reactions. Therefore, TWP could offer therapeutic benefits to patients with PMN, DKD, and severe HSPN, with a minimal increase in the risk of side effects.

Sedentary behaviour among elderly patients after total knee arthroplasty and its influencing factors.

To understand the status of sedentary behaviour in elderly patients after total knee arthroplasty and analyse its influencing factors so as to provide a reference for developing targeted interventions. Conveniently selected elderly patients undergoing total knee arthroplasty (> 6 months) in a tertiary hospital in Jiangsu Province were investigated using a general information questionnaire, the Charlson Comorbidity Index, patients' self-reported sedentary behaviour information, the WOMAC Score, The Groningen Orthopaedic Social Support Scale, and Lee's Fatigue. The median daily sedentary time was 5.5 h (4.5 h, 6.625 h) in 166 elderly patients after total knee arthroplasty, of whom 82 (49.40%) showed sedentary behaviour (≥ 6 h per day). Logistic regression analysis showed that being retired/unemployed (OR = 8.550, 95% CI 1.732-42.207, P = 0.0084), having a CCI score ≥ 3 (OR = 9.018, 95% CI 1.288-63.119, P < 0.0001), having high WOMAC scores (OR = 1.783, 95% CI 1.419-2.238, P < 0.0001), having a high social support score (OR = 1.155, 95% CI 1.031-1.294, P = 0.0130), and having a fatigue score ≥ 5 (OR = 4.848, 95% CI 1.084-21.682, P = 0.0389) made patients more likely to be sedentary. The sedentary time of elderly patients after total knee arthroplasty is long, and sedentary behaviour is common among them. Healthcare professionals should develop targeted sedentary behaviour interventions based on the influencing factors of sedentary behaviour in order to reduce the occurrence of sedentary behaviour in elderly patients after total knee arthroplasty.

Yak meat content in feed and its impact on the growth of rats.

To evaluate the effects of varying proportions of yak meat in feed on the growth of rats and provide a theoretical basis for selecting the optimal feed proportion suitable for rats. This study was designed as a one-variable experiment. Fifty male rats were divided into five groups. The ratios of yak meat to basal feed of rats in four dietary treatment groups were 2:8, 4:6, 6:4, and 8:2, respectively, while those in the control group were only provided a basal diet. In the feeding experiment, the body weights of the rats were recorded on Day 0 and subsequently in the first, second, third, and fourth weeks, along with quantities of feed intake. The body and tail lengths, as well as the waist circumference of the rats, were measured, and blood samples were collected in the fourth week for routine blood and biochemistry investigations. The rats in the 4:6 feed group had the best body condition. They had normal body and tail lengths, smaller waist circumferences, good posture, and were in better overall health than rats in the other groups. The results indicate that the 4:6 diet was optimal for enhancing rats' growth performance compared to the other diets.