Circadian rhythm is an endogenous biological clock mechanism that enables organisms to adapt to the earth’s alternation of day and night. It plays a fundamental role in regulating physiological functions and behavioral patterns, such as sleep, feeding, hormone levels and body temperature. By aligning these processes with environmental changes, circadian rhythm plays a pivotal role in maintaining homeostasis and promoting optimal health. However, modern lifestyles, characterized by irregular work schedules and pervasive exposure to artificial light, have disrupted these rhythms for many individuals. Such disruptions have been linked to a variety of health problems, including sleep disorders, metabolic syndromes, cardiovascular diseases, and immune dysfunction, underscoring the critical role of circadian rhythm in human health. Among the numerous systems influenced by circadian rhythm, the skin—a multifunctional organ and the largest by surface area—is particularly noteworthy. As the body’s first line of defense against environmental insults such as UV radiation, pollutants, and pathogens, the skin is highly affected by changes in circadian rhythm. Circadian rhythm regulates multiple skin-related processes, including cyclic changes in cell proliferation, differentiation, and apoptosis, as well as DNA repair mechanisms and antioxidant defenses. For instance, studies have shown that keratinocyte proliferation peaks during the night, coinciding with reduced environmental stress, while DNA repair mechanisms are most active during the day to counteract UV-induced damage. This temporal coordination highlights the critical role of circadian rhythms in preserving skin integrity and function. Beyond maintaining homeostasis, circadian rhythm is also pivotal in the skin’s repair and regeneration processes following injury. Skin regeneration is a complex, multi-stage process involving hemostasis, inflammation, proliferation, and remodeling, all of which are influenced by circadian regulation. Key cellular activities, such as fibroblast migration, keratinocyte activation, and extracellular matrix remodeling, are modulated by the circadian clock, ensuring that repair processes occur with optimal efficiency. Additionally, circadian rhythm regulates the secretion of cytokines and growth factors, which are critical for coordinating cellular communication and orchestrating tissue regeneration. Disruptions to these rhythms can impair the repair process, leading to delayed wound healing, increased scarring, or chronic inflammatory conditions. The aim of this review is to synthesize recent information on the interactions between circadian rhythms and skin physiology, with a particular focus on skin tissue repair and regeneration. Molecular mechanisms of circadian regulation in skin cells, including the role of core clock genes such as Clock, Bmal1, Per and Cry. These genes control the expression of downstream effectors involved in cell cycle regulation, DNA repair, oxidative stress response and inflammatory pathways. By understanding how these mechanisms operate in healthy and diseased states, we can discover new insights into the temporal dynamics of skin regeneration. In addition, by exploring the therapeutic potential of circadian biology in enhancing skin repair and regeneration, strategies such as topical medications that can be applied in a time-limited manner, phototherapy that is synchronized with circadian rhythms, and pharmacological modulation of clock genes are expected to optimize clinical outcomes. Interventions based on the skin’s natural rhythms can provide a personalized and efficient approach to promote skin regeneration and recovery. This review not only introduces the important role of circadian rhythms in skin biology, but also provides a new idea for future innovative therapies and regenerative medicine based on circadian rhythms.

Objective To explore the feasibility and operability in identifying the therapeutic dominant stages of traditional Chinese medicine(TCM)based on subdivision model of disease course.Methods The hierarchical Bayesian model was used to differentiate the disease course of 125 cases of premature ovarian failure(POF),and the disease course of POF were divided into the occult stage,diminished ovarian reserve(DOR)stage,premature ovarian insufficiency(POI)stage,and POF stage.An then the paired sample t-test,Pearson correlation analysis and expert in-depth interview were used for the analysis of the therapeutic effects of TCM for POF at various stages.Results(1)Compared with POF stage,DOR and POI stages were frequently intervened by Chinese patent medicine.(2)In DOR(complicated with POI)stage and POF stage,there was significant difference between the degree of TCM intervention and the therapeutic effect(t =-3.70,P＜0.001).(3)The degree of TCM intervention was positively correlated with treatment outcomes in the DOR stage(r = 0.679,P＜0.001),so did in the POF stage(r = 0.432,P＜0.001),but the correlation in the POF stage was slightly lower than that in the DOR stage.(4)The results of in-depth interviews with experts of TCM gynecology showed that in the concealed phase of POF,the prognosis would be most favorable if TCM regulation and intervention were performed.In the DOR stage and POI stage,treatment with Chinese medicine prescriptions usually brought about better curative effect and prognosis.For the patients at POF stage,the therapeutic effect of TCM depended on the patients'compliance and the treatment course,and the effect was relatively not as good as that of the previous stages.Conclusion In the DOR stage and POF stage,the higher the degree of TCM intervention,the better the prognosis will be achieved for the patients treated with western medicine.In the POF stage,the efficacy of TCM intervention is reduced to a certain extent compared with the DOR stage.The results indicated that it is feasible and operable to identify the TCM therapeutic dominant stages based on the subdivision model of disease course.

The pathogenesis of osteoarthritis (OA) is related to a variety of factors such as mechanical overload, metabolic dysfunction, aging, etc., and is a group of total joint diseases characterized by intra-articular chondrocyte apoptosis, cartilage fibrillations, synovial inflammation, and osteophyte formation. At present, the treatment methods for osteoarthritis include glucosamine, non-steroidal anti-inflammatory drugs, intra-articular injection of sodium hyaluronate, etc., which are difficult to take effect in a short period of time and require long-term treatment, so the patients struggle to adhere to doctor’s advice. Some methods can only provide temporary relief without chondrocyte protection, and some even increase the risk of cardiovascular disease and gastrointestinal disease. In the advanced stages of OA, patients often have to undergo joint replacement surgery due to pain and joint dysfunction. Mitochondrial dysfunction plays an important role in the development of OA. It is possible to improve mitochondrial biogenesis, quality control, autophagy balance, and oxidative stress levels, thereby exerting a protective effect on chondrocytes in OA. Therefore, compared to traditional treatments, improving mitochondrial function may be a potential treatment for OA. Here, we collected relevant literature on mitochondrial research in OA in recent years, summarized the potential pathogenic factors that affect the development of OA through mitochondrial pathways, and elaborated on relevant treatment methods, in order to provide new diagnostic and therapeutic ideas for the research field of osteoarthritis.

The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.

The purpose of this study was to enrich the genomic information and provide a basis for further development and utilization of Polygonatum kingianum. The fresh rhizome of P. kingianum was used as the experimental material, and the full-length transcriptome was sequenced by PacBio Sequel platform. The final measured polymerase reads were 1 120 485, with a total of 77.73 GB of data. In NR database, 41 864 homologous sequence alignments were aligned to 5 species; 40 506 were annotated in the KOG database and classified into 26 categories based on their functionality; 69 060 GO annotated 32 functional groups divided into 3 categories: cellular components, molecular functions, and biological processes; 45 779 annotations were added to 145 metabolic pathways in the KEGG database. Among them, there are 127 identified transcripts related to polysaccharide synthesis in the glycolysis/gluconeogenesis metabolic pathway, 144 in the starch and sucrose metabolic pathway, 85 in the amino acid sugar and nucleotide sugar metabolic pathway, and 69 in the fructose and mannose metabolic pathway. In addition, 1 781 transcription factors were detected, distributed in 37 transcription factor families; 180 293 SSR loci were detected, among which single base repeats accounted for the most, accounting for 30.48% of all base repeats, and at least five base repeats, accounting for only 0.14% of single base repeats. The results of this study provide important data supporting for enriching the genomic information of P. kingianum and exploring its effective biosynthetic pathway.

ObjectiveThe detection of RNA single nucleotide polymorphism (SNP) is of great importance due to their association with protein expression related to various diseases and drug responses. At present, splintR ligase-assisted methods are important approaches for RNA direct detection, but its specificity will be limited when the fidelity of ligases is not ideal. The aim of this study was to create a method to improve the specificity of splintR ligase for RNA detection. MethodsIn this study, a dual-competitive-padlock-probe (DCPLP) assay without the need for additional enzymes or reactions is proposed to improve specificity of splintR ligase ligation. To verify the method, we employed dual competitive padlock probe-mediated rolling circle amplification (DCPLP-RCA) to genotype the CYP2C9 gene. ResultsThe specificity was well improved through the competition and strand displacement of dual padlock probe, with an 83.26% reduction in nonspecific signal. By detecting synthetic RNA samples, the method demonstrated a dynamic detection range of 10 pmol/L-1 nmol/L. Furthermore, clinical samples were applied to the method to evaluate its performance, and the genotyping results were consistent with those obtained using the qPCR method. ConclusionThis study has successfully established a highly specific direct RNA SNP detection method, and provided a novel avenue for accurate identification of various types of RNAs.

BACKGROUND:CXC motif chemokine 5(CXCL5)is a neutrophil activating peptide derived from epithelial cells,which may be involved in arterial diseases.However,there is yet no report on the effect of CXCL5 in vascular calcification. OBJECTIVE:To explore the role of CXCL5 in the vascular calcification of carotid atherosclerosis(CAS). METHODS:(1)Cytological experiment:Mouse vascular smooth muscle cells(VSMCs)were divided into five groups:osteogenic medium group,Vector group(vector,blank plasmid transfected into VSMCs),CXCL5 group(CXCL5 plasmid transfected into VSMCs),si-NC group(CXCL5 negative control siRNA transfected into VSMCs),si-CXCL5 group(CXCL5 siRNA transfected into VSMCs),Vector+LY2157299 group and CXCL5+LY2157299 group(LY2157299 transferred into the cells 24 hours after cell transfection).Alizarin red staining,alkaline phosphatase staining,and calcium content determination were performed to evaluate the osteogenic differentiation level of VSMCs.(2)Animal experiment:Forty-eight ApoE-/-mice were randomly divided into four groups(n=12 per group):Con+si-NC group,Con+si-CXCL5 group,CAS+si-NC group and CAS+si-CXCL5 group.Animal models were not prepared in the first two groups,in which si-NC or si-CXCL5 lentivirus was injected into the tail vein;carotid atherosclerosis models were made in the latter two groups,in which si-NC or si-CXCL5 lentivirus was injected into the tail vein.Von Kossa staining and immunohistochemical staining were used to evaluate carotid vascular calcification and the expression of CXCL5 and transforming growth factor-β receptor 1(TGFBR1)in mice. RESULTS AND CONCLUSION:In the CXCL5 group,the protein level of runt-related transcription factor 2(RUNX2)was up-regulated and the level of α-smooth muscle actin was down-regulated,in contrary to the findings in the si-CXCL5 group.In addition,CXCL5 overexpression upregulated the level of TGFBR1,while CXCL5 knockdown inhibited the level of TGFBR1.Compared with the Vector group,the intensity of alizarin red staining,alkaline phosphatase activity and calcium content in the CXCL5 group increased significantly(P<0.05).Compared with the si-NC group,the intensity of alizarin red staining,alkaline phosphatase activity and calcium content in the si-CXCL5 group decreased significantly(P<0.05).When LY2157299 inhibited TGFBR1 expression,the osteogenic differentiation of VSMCs induced by CXCL5 was reduced.Compared with the Con+si-NC group,the expression of CXCL5 protein in the carotid artery and calcification area in the CAS+si-NC group increased significantly(P<0.05).Compared with the CAS+si-NC group,the expression of CXCL5 protein in the carotid artery and vascular calcification area in the CAS+si-CXCL5 group decreased significantly(P<0.05).In addition,compared with the Con+si-NC group,the expression of RUNX2 protein in the carotid artery in the CAS+si-NC group increased significantly(P<0.05),while the expression of α-smooth muscle actin protein decreased significantly(P<0.05).Compared with the CAS+si-NC group,the expression of RUNX2 protein in the carotid artery in CAS+si-CXCL5 group decreased significantly(P<0.05),while the expression of α-smooth muscle actin protein increased significantly(P<0.05).In conclusion,CXCL5 can induce osteogenic transformation of VSMCs by activating the TGFBR1 pathway,and inhibition of CXCL5 expression is effective in improving carotid arterial calcification in CAS mice.