Osteosarcopenia (OS) is a multifactorial, multiaetiologic degenerative metabolic syndrome in which sarcopenia coexists with osteoporosis, and its influences are related to aging-induced mechanics, genetics, inflammatory factors, endocrine disorders, and irregular lifestyles. With the accelerated aging process in our country, osteosarcopenia has become a public health problem that cannot be ignored, with a higher risk of falls, fractures, impaired mobility and death. In recent years, scholars at home and abroad have conducted a lot of research on osteosarcopenia, but their pathogenesis is still unclear. Understanding the signaling pathways associated with osteosarcopenia is of great significance for further research on the pathogenesis of these disorders and for finding new targets for treatment. Studies have shown that activation of the PI3K/Akt signaling pathway promotes osteoblast differentiation as well as skeletal muscle regeneration, indicating that inhibition of thePI3K/Akt signaling pathway is closely related to the development of osteosarcopenia. Muscle factor-mechanical stress interactions can maintain osteoblast viability by activating the Wnt/β-catenin signaling pathway, suggesting that Wnt signaling is important in muscle and bone crosstalk. The Notch signaling pathway also plays an important role in improving bone and muscle mass and function, but different researchers hold different views, which need to be further validated and refined in subsequent studies. Exercise, as an existing non-pharmacological treatment with strong and sustained effects on physical function and muscle strength, also significantly increases bone density in osteoporosis patients, which may be mainly due to the fact that exercise induces changes in the form and function of bones, in the form of muscular pulling and indirectly improves the bone mass, and changes in the bone strength can also change the number, shape as well as the function of the muscles. At the same time, the mechanism of different exercise modalities focuses on different aspects, and there are differences in exercise time, exercise intensity, and therapeutic effects in the implementation of interventions. Aerobic exercise can improve the quality of skeletal muscle and increase the expression of osteogenesis-related genes by stimulating mitochondrial biosynthesis, as well as improve the quality and strength of bones and muscles through the Wnt/β- catenin and PI3K/Akt signaling pathways, effectively preventing and controlling the occurrence of musculoskeletal disorders. High-intensity resistance exercise has a significant effect on improving the quality of muscles and bone mineral density, but older people with osteosarcopenia suffer from a decline in muscle quality and strength, and a decline in bone mineral density, which makes them very susceptible to fracture, so they should select the intensity of the training in a gradual and orderly manner, from small to large. What kind of exercise intensity and exercise modalities are most effective in improving the occurrence and development of osteosarcopenia needs to be further investigated. Therefore, this paper mainly reviews the epidemiology of osteosarcopenia, diagnostic criteria, the related signaling pathways (PI3K/Akt pathway, Wnt/β-catenin pathway, Notch pathway, NF-κB pathway) that jointly regulate the metabolic process of myocytes and skeletal cells, as well as the interventional effects of different exercise modes on osteosarcopenia, with the aim of providing theoretical bases for the clinical treatment of osteosarcopenia, as well as enhancing the preventive capacity of the disease in old age.

Osteoporosis leads to an imbalance in bone remodelling, where bone resorption is greater than bone formation and osteoclast degradation increases, resulting in severe bone loss. Autophagy is a lysosomal degradation pathway that regulates the proliferation, differentiation, and apoptosis of various bone cells (including osteoblasts, osteoclasts, and osteoclasts), and is deeply involved in the bone remodelling process. In recent years, the role of autophagy in the progression of osteoporosis and related bone metabolic diseases has received more and more attention, and it has become a research hotspot in this field. Summarising the existing studies, it is found that senile osteoporosis is the result of a combination of factors. On the one hand, it is the imbalance of bone remodelling and the increase of bone resorption/bone formation ratio with ageing, which causes progressive bone loss. On the other hand, aging leads to a general decrease in the level of autophagy, a decrease in the activity of osteoblasts and osteoclasts, and an inhibition of osteogenic differentiation. The lack of oestrogen leads to the immune system being in a low activation state, and the antioxidant capacity is weakened and inflammatory response is increased, inducing autophagy-related proteins to participate in the transmission of inflammatory signals, excessive accumulation of reactive oxygen species (ROS) in the skeleton, and negatively regulating bone formation. In addition, with aging and the occurrence of related diseases, glucocorticoid treatments also mediate autophagy in bone tissue cells, contributing to the decline in bone strength. Exercise, as an effective means of combating osteoporosis, improves bone biomechanical properties and increases bone density. It has been found that exercise induces oxidative stress, energy imbalance, protein defolding and increased intracellular calcium ions in the organism, which in turn activates autophagy. In bone, exercise of different intensities activates messengers such as ROS, PI3K, and AMP. These messengers signal downstream cascades, which in turn induce autophagy to restore dynamic homeostasis in vivo. During exercise, increased production of AMP, PI3K, and ROS activate their downstream effectors, AMPK, Akt, and p38MAPK, respectively, and these molecules in turn lead to activation of the autophagy pathway. Activation of AMPK inhibits mTOR activity and phosphorylates ULK1 at different sites, inducing autophagy. AMPK and p38 up-regulate per-PGC-1α activity and activate transcription factors in the nucleus, resulting in increased autophagy and lysosomal genes. Together, they activate FoxOs, whose transcriptional activity controls cellular processes including autophagy and can act on autophagy key proteins, while FoxOs proteins are expressed in osteoblasts. Exercise also regulates the expression of mTORC1, FoxO1, and PGC-1 through the PI3K/Akt signalling pathway, which ultimately plays a role in the differentiation and proliferation of osteoblasts and regulates bone metabolism. In addition, BMPs signaling pathway and long chain non-coding RNAs also play a role in the proliferation and differentiation of osteoblasts and autophagy process under exercise stimulation. Therefore, exercise may become a new molecular regulatory mechanism to improve osteoporosis through the bone autophagy pathway, but the specific mechanism needs to be further investigated. How exercise affects bone autophagy and thus prevents and treats bone-related diseases will become a future research hotspot in the fields of biology, sports medicine and sports science, and it is believed that future studies will further reveal its mechanism and provide new theoretical basis and ideas.

AIM To study the extraction process,enzymatic properties and practical application of glucuronic hydrolase in Scutellaria baicalensis stems and leaves(sbsl GUS).METHODS With granularity,water consumption,extraction time and extraction frequency as influencing factors,enzymatic activity as an evaluation index,the extraction process was optimized by orthogonal test on the basis of single factor test.The relationship between substrate(baicalin)concentration and enzymolysis rate,after which Vmax and Km were calculated,the effects of pH value,temperature and metal ion on enzymatic activity were investigated,pH stability and heat stability were evaluated.sbsl GUS was adotped in the enzymolysis of baicalin to prepare baicalein,then the effects of pH value,temperature,reaction time,initial substrate concentration and enzyme addition on transfer rate were investigated.RESULTS The optimal extraction process was determined to be 40 mesh for granularity,10 times for water consumption,15 min for extraction time,and 3 times for extraction frequency.The enzymolysis accorded with the kinetics of enzymatic reaction,Km was 0.006 3 mol/L,Vmax was 70.42 μmol/h,the strongest enzymatic activity was found at the pH value of 6.0,temperature of 45℃and metal ion of 100 mmol/L Cu2+,sbsl GUS demonstrated good stability at the ranges of 4.0-7.0 for pH value and 4-30℃for temperature.The optimal preparation process was determined to be 6.0 for pH value,45℃for temperature,more than 12 h for reaction time,67.2 mmol/L for initial substrate concentration,and 1 mL/0.269 mmol baicalin for enzyme addition,the transfer rate was 97.83%.CONCLUSION sbsl GUS enzymolysis exhibits high efficiency and mild condition,which can provide a simple preparation method for obtaining baicalein,and expand the application path of Scutellaria baicalensis stems and leaves.

Objective To observe the effect of omeprazole enteric-coated capsules on clinical symptoms and serum inflammatory factor levels in children with chronic gastritis and peptic ulcer.Methods Children with chronic gastritis and peptic ulcer were divided into treatment group and control group by random number table method.The control group was given triple therapy of ranitidine hydrochloride tablets,amoxicillin and clarithromycin,while the treatment group was treated with omeprazole enteric-coated capsules combined with amoxicillin and clarithromycin.Clinical efficacy,symptom relief time,and changes in serum motilin(MOT),gastrin(GAS)and inflammatory factors[interlrukin-6(IL-6)and interlrukin-8(IL-8)]were compared between the two groups.Results There were 48 cases in treatment group and 48 cases in control group.After treatment,the total effective rates in treatment group and control group were 93.74％(45 cases/48 cases)and 85.42％(41 cases/48 cases),with significant difference(P＜0.05).After treatment,the disappearance time of ulcer induced pain in treatment group and control group were(1.51±0.26)and(2.08±0.42)d;the disappearance time of acid regurgitation were(2.29±0.40)and(2.93±0.33)d;the disappearance time of burning sensation were(2.37±0.21)and(2.85±0.54)d;the length of hospital stay were(6.21±1.07)and(6.94±1.25)d;serum MOT levels were(298.48±35.15)and(273.58±31.25)pg·mL-1;serum GAS levels were(167.28±19.46)and(128.32±18.61)ng·L-1;IL-6 levels were(58.67±5.39)and(76.14±6.63)mg·mL-1;IL-8 levels were(50.08±5.16)and(58.68±5.49)mg·mL-1.The above indexes were significantly different between control group and treatment group(all P＜0.05).The total incidence of adverse drug reactions in treatment group and control group were 8.33％and 12.50％,with no statistical significance(P＞0.05).Conclusion Omeprazole enteric-coated capsules in the treatment of children with chronic gastritis and peptic ulcer can effectively alleviate various clinical symptoms and improve clinical efficacy.At the same time,it can lower serum levels of inflammatory factors and improve inflammation,with good effect.

In recent years, nucleic acid therapy, as a revolutionary therapeutic tool, has shown great potential in the treatment of genetic diseases, infectious diseases and cancer. Lipid nanoparticles (LNPs) are currently the most advanced mRNA delivery carriers, and their emergence is an important reason for the rapid approval and use of COVID-19 mRNA vaccines and the development of mRNA therapy. Currently, mRNA therapeutics using LNP as a carrier have been widely used in protein replacement therapy, vaccines and gene editing. Conventional LNP is composed of four components: ionizable lipids, phospholipids, cholesterol, and polyethylene glycol (PEG) lipids, which can effectively load mRNA to improve the stability of mRNA and promote the delivery of mRNA to the cytoplasm. However, in the face of the complexity and diversity of clinical diseases, the structure, properties and functions of existing LNPs are too homogeneous, and the lack of targeted delivery capability may result in the risk of off-targeting. LNPs are flexibly designed and structurally stable vectors, and the adjustment of the types or proportions of their components can give them additional functions without affecting the ability of LNPs to deliver mRNAs. For example, by replacing and optimizing the basic components of LNP, introducing a fifth component, and modifying its surface, LNP can be made to have more precise targeting ability to reduce the side effects caused by treatment, or be given additional functions to synergistically enhance the efficacy of mRNA therapy to respond to the clinical demand for nucleic acid therapy. It is also possible to further improve the efficiency of LNP delivery of mRNA through machine learning-assisted LNP iteration. This review can provide a reference method for the rational design of engineered lipid nanoparticles delivering mRNA to treat diseases.

Cyclin-dependent kinases (CDKs) are proline-induced serine/threonine kinases that are primarily involved in the regulation of cell cycle, gene transcription, and cell differentiation. In general, CDKs are activated by binding to specific regulatory subunits of cell cycle proteins and are regulated by phosphorylation of specific T-loops by CDK activated kinases. In the CDKs family, cyclin-dependent kinase 5 (CDK5) is a specialized member whose activity is triggered only by interaction with p35 and p39, which do not have the same sequence as the cell cycle proteins, and this may be one reason why CDK5 is distinguished from other CDK members by its structural and functional differences. In addition, unlike most CDK members that require phosphorylation at specific sites to function, CDK5 does not require such phosphorylation, and it can be activated simply by binding to p35 and p39. More notably, inhibitors that are commonly used to inhibit the activity of other CDK members have almost zero effect on CDK5. In contrast, CDK5, as a unique CDK family member, plays an important role in the development of numerous diseases. In metabolic diseases, elevated CDK5 expression leads to decreased insulin secretion, increased foam cell formation and triggers decreased bone mass in the body, thus accelerating metabolic diseases, and the role of CDK5 in bone biology is gradually gaining attention, and the role of CDK5 in bone metabolic diseases may become a hotspot for research in the future; in neurodegenerative diseases, hyperphosphorylation of Tau protein is an important hallmark of Alzheimer’s disease development, and changes in CDK5 expression are associated with Tau protein phosphorylation and nerve death, indicating that CDK5 is highly related to the development of the nervous system; in tumor diseases, the role of CDK5 in the proliferation, differentiation and migration and invasion of tumor cells marks the development of tumorigenesis, but different researchers hold different views, and further studies are needed in the follow-up. Therefore, the study of its mechanism of action in diseases can help to reveal the pathogenesis and pathological process of diseases. Appropriate exercise not only helps in the prevention of diseases, but also plays a positive role in the treatment of diseases. Exercise-induced mechanical stress can improve bone microstructure and increase bone mass in osteoporosis patients. In addition, exercise can effectively inhibit neuronal apoptosis and improve mitochondrial dysfunction, more importantly, appropriate exercise can inhibit the proliferation of cancer cells to a certain extent. It can be seen that exercise occupies a pivotal position in the prevention and treatment of pathologic diseases. It has been shown that exercise can reduce the expression of CDK5 and affect the pathological process of neurological diseases. Currently, there is a dearth of research on the specific mechanisms of CDK5’s role in improving disease outcomes through exercise. In order to understand its effects more comprehensively, subsequent studies need to employ diverse exercise modalities, targeting patients with various types of diseases or corresponding animal models for in-depth exploration. This article focuses on the pathological functions of CDK5 and its relationship with exercise, with a view to providing new insights into the prevention and treatment of disease by CDK5.

Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

Objective To investigate the incidence and risk factors for acute kidney injury(AKI)in children with primary nephrotic syndrome(PNS),as well as the role of neutrophil gelatinase-associated lipocalin(NGAL)and kidney injury molecule-1(KIM-1)in the early identification of AKI in these children.Methods A prospective collection of clinical data from children hospitalized with PNS at the Children's Hospital of the Capital Institute of Pediatrics from January 2021 to October 2022 was conducted.The children were divided into two groups based on the presence of AKI:the AKI group(47 cases)and the non-AKI group(169 cases).The risk factors for AKI in children with PNS were identified by multivariate logistic regression analysis.Urinary KIM-1 and NGAL levels were compared between the AKI and non-AKI groups,as well as among the different stages of AKI.Results The incidence of AKI in children with PNS was 21.8%.Multivariate logistic regression analysis revealed that steroid-resistant nephrotic syndrome,gastrointestinal infections,and heavy proteinuria were independent risk factors for AKI in these children with PNS(P<0.05).Urinary KIM-1 and NGAL levels were higher in the AKI group compared to the non-AKI group(P<0.05),and the urinary NGAL and KIM-1 levels in the AKI stage 2 and stage 3 subgroups were higher than those in the AKI stage 1 subgroup(P<0.017).Conclusions KIM-1 and NGAL can serve as biomarkers for the early diagnosis of AKI in children with PNS.Identifying high-risk populations for AKI in children with PNS and strengthening the monitoring of related risk factors is of significant importance.

Objective To compare the clinical efficacy of the posterior hemipelvectomy of the greater trochanter approach with the standard Kocher-Langenbeck(K-L)approach in the treatment of posterior acetabulum wall fractures and to explore a more optimal approach for the treatment of posterior acetabulum wall fractures.Methods Total of 26 patients with posterior ac-etabulum wall fractures were retrospectively analysed and divided into two groups:the posterior hemipelvectomy of the greater trochanter group(test group)and the standard K-L approach group(control group).In the test group,there were 24 patients including 16 males and 8 females with an average age of(42.00±4.52)years old,the time of injury to surgery was(6.75±1.15)d.In the control group,there were 23 patients including 16 males and 7 females with an average age of(41.00±5.82)years old,the time of injury to surgery was(7.09±1.20)days.The total hospital stay,length of incision,operation time,intraoperative bleeding,postoperative drainage,discharge,fracture reduction quality(Matta criteria),hip abduction muscle strength,hip func-tion(Merle d'Aubigne-Postel score),postoperative complications and the incidence of ectopic ossification were compared.Results All cases were followed up for 6 months.There was no significant difference in incision length,intraoperative bleeding and postoperative drainage between two groups(P＞0.05).However,the operation time of the test group was shorter than that of the control group(P＜0.05).There was no statistically significant difference in fracture reduction and hip function between two groups(P＞0.05).The hip abduction muscle strength of test group was better than that of control group(P＜0.05).In addition,there was no significant difference in the incidence of postoperative complications and heterotopic ossification between two groups(P＞0.05).Conclusion Compared with the standard K-L approach,the posterior hemipelvectomy of the greater trochanter approach can shorten the operative time,has better recovery of the postoperative hip abduction muscle strength,ex-poses the view of the fracture involving the more comminuted posterior acetabulum wall or the fracture of the roof of the socket,improved the rate of fracture anatomical repositioning,provides a new idea for the clinical treatment of posterior acetabulum wall fractures,and allows patients to perform functional exercises at an early stage.

Objective To analyze the stress changes of thoracic vertebra(T)11-sacrum(S)titanium rods in patients with ankylosing spondylitis after vertebral column decancellation(VCD)osteotomy,and provide reference for the selection and improvement of titanium rods before surgery.Methods The original data of the continuous scanning tomographic images of patients with ankylosing spondylitis after VCD osteotomy were imported into Mimics 21.0 in DICOM format,and T11-S vertebrae,screws and titanium rods were respectively reconstructed.They were imported into 3-Matic to establish a preliminary geometric modeling,and then processed with noise removal,paving,smoothing,etc.The improved model was imported into Hypermesh 10 software for grid division,and the material was imported into ANSYS 19.2 to display the finite element model after attribute assignment,Set the boundary and load conditions,and measure the stress value at the connection between the screw and the titanium rod.Results Under neutral position,forward bending,lateral bending,and axial rotation conditions,the titanium rod had the highest stress at the upper vertebrae(T11)and the lowest stress at the top vertebrae(L3);Under the backward extension condition,the titanium rod has the highest stress at the lower end vertebra(L5).Conclusion In the upper and lower vertebrae,it is possible to consider increasing the diameter of the titanium rod,enhancing its hardness,or changing it to a double rod.