ObjectiveTo establish background data for a 90-day feeding trial of SD rats to ensure the reliability of research data. MethodsBackground data from six independent 90-day feeding trials of SD rats conducted by the National Center for Safety Evaluation of Drugs from 2020 to 2023 were summarized. These studies involved a blank control group of 120 SPF-grade 4-week-old SD rats, with an equal number of males and females, which were only given standard full-nutrient pelleted rat feed. After the quarantine period, the animals were observed for an additional 90 days, followed by intraperitoneal injection of Zoletil (50 mg/mL) for anesthesia, blood sampling, euthanasia, and necropsy. By analyzing the data from the blank control group, a relevant background database for SD rats was established. ResultsBoth male and female rats exhibited steady weight gain, with a more pronounced increase in male rats. Within 90 days, the average body weight of male and female rats increased to over 500 g and 300 g, respectively. Three weeks later, the average daily food intake of male rats stabilized at approximately 25~28 g per rat, while that of female rats remained stable at approximately 16~19 g per rat. The food utilization rate of all animals gradually decreased from the first week of the experiment. In the white blood cell (WBC) differential count results, significant differences were observed in the counts of WBCs, neutrophils (Neut), lymphocytes (Lymph), and monocytes (Mono) between males and females (P<0.001). However, there were no significant differences in the percentages of neutrophil (%Neut), lymphocyte (%Lymph), and monocyte (%Mono) between the sexes (P>0.05). The average red blood cell count (RBC), hemoglobin concentration (HGB), hematocrit (HCT), platelet count (PLT), prothrombin time (PT), and activated partial thromboplastin time (APTT) were higher in male animals than in female animals (P<0.05). The average values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine phosphokinase (CK), lactate dehydrogenase (LDH), glucose (GLU), and triglyceride (TG) in male rats were higher than those in female rats (P<0.05). The urinary pH range for male animals was 5.0 to 8.5, while for female animals it was 6.5 to 9.0. The majority of male animals had a urinary specific gravity lower than 1.020, and the majority of female animals had a urinary specific gravity lower than 1.015. The weights of various organs (excluding the adrenal glands and reproductive organs) in male animals were heavier than those in female animals (P<0.001), while the organ/body weight ratios (excluding the kidneys and reproductive organs) of female animals were higher than those of male animals (P<0.001). ConclusionThis study summarizes the background reference ranges for body weight, food intake, hematology, and serum biochemistry indicators in SPF-grade SD rats in the untreated control group from six 90-day feeding trials conducted by the National Center for Safety Evaluation of Drugs. It provides important reference data for related research. By summarizing the background and spontaneous histopathological changes in rats, this study aids in the standardization and normalization of subsequent research, as well as in the evaluation and analysis of abnormal results.

Objective To construct a stable synovial cell line MH7A from rheumatoid arthritis(RA)patients using lentiviral vectors that interfere with the expression of tumor necrosis factor receptor associated factor 2(TRAF2),and to study the role of TNF-α-TRAF2 signaling in MH7A abnormal proliferation.Methods Based on the design principles of human TRAF2 gene sequence and shRNA sequence,three pairs of TRAF2 shRNA interference se-quences were designed and synthesized.The primers were annealed by PCR,and a linear vector was obtained by double enzyme digestion PLKO.1-puro.The linearized vector was connected to the annealed primers through Solu-tion I,and the connected products were introduced into receptive cells.The plates were coated,and positive colo-nies were selected for sequencing.Three different recombinant plasmids of PLKO.1-TRAF2-shRNA lentivirus were constructed,and lentivirus packaging plasmids was used to package logarithmic growth phase HEK 293T cells.Vi-rus solution was collected to infect MH7A cells.At the same time,puromycin was used to screen MH7A stable transgenic strains with low TRAF2 expression.CCK-8 method,Western blot,and qPCR were used to detect the proliferation function of MH7A induced by TNF-α and low expression of TRAF2,as well as downstream signal TRAF2,P65 protein expression and mRNA levels.Results PLKO.1-TRAF2-shRNA(1),PLKO.1-TRAF2-shR-NA(2),and PLKO.1-TRAF2-shRNA(3)lentivirus vector plasmids and control group lentivirus vector plasmids PLKO.1-puro were successfully constructed.The three TRAF2-shRNA lentivirus vector plasmids and control group lentivirus vector plasmids PLKO.1-puro were respectively introduced into the lentivirus packaging plasmid of HEK 293T to obtain virus solution.After infecting MH7A cells with the virus solution,they were treated with puromycin(2.00 μ G/mL)screening and obtaining MH7A stable transgenic plants after 2 days.Through qPCR and Western blot results,it was found that the expression of TRAF2 mRNA and protein in PLKO.1-TRAF2-shRNA(1)MH7A stably transfected cells was significantly reduced compared to the negative control group.The results of CCK-8 and Western blot showed that after knocking down TRAF2 in MH7A,the proliferation of MH7A cells with low TRAF2 expression induced by TNF-α and the phosphorylation level of P65 were significantly reduced.Conclusion A sta-ble transgenic strain of PLKO.1-TRAF2-shRNA(1)MH7A cells was successfully constructed to investigate the role of TNF-α-TRAF2 signal activation in mediating abnormal proliferation of RA synovial cells.

ObjectiveTo compare the effects of different doses and withdrawal time of 4-vinylcyclohexene diepoxide （VCD） on the reproductive endocrine levels of female rats， and to explore the effective， stable， and safe dosage of VCD for constructing a premature ovarian insufficiency （POI） rat model. MethodSD rats with regular estrous cycles were randomly divided into three groups： blank group， low-dose VCD group （80 mg·kg^-1·d^-1）， and high-dose VCD group （160 mg·kg^-1·d^-1）， with 24 rats in each group. After drug intervention， samples were collected on the 15th day （D15） and the 45th day （D45） after intervention. The general condition， rate of estrous cycle disturbance， serum hormone levels， ovarian histomorphology， follicle count， pregnancy outcome， and the protein and mRNA expression of transforming growth factor （TGF）-β and Smad2/3 were assessed. ResultCompared with the blank group， the low-dose VCD group showed no significant differences in the rate of estrous cycle disturbance or serum follicle-stimulating hormone （FSH）， luteinizing hormone （LH）， and estradiol （E₂） levels. Ovarian tissue was damaged. Specifically， the number of primordial and primary follicles decreased on D15 （P<0.01）， and the number of secondary follicles （P<0.01） and antral follicles （P<0.05） further decreased on D45. The litter number decreased on D15 （P<0.05）， but there was no significant difference on D45. Furthermore， TGF-β protein levels increased on D15 （P<0.05） and D45 （P<0.01）. The Smad2/3 levels increased on D45 （P<0.01）， and TGF-β and Smad2/3 mRNA levels increased on D45 （P<0.05）. Compared with the results in the blank group， the disturbance rate of the estrous cycle increased on D45 in the high-dose VCD group （P<0.01）. The serum of FSH and LH increased （P<0.01）， while E₂ decreased （P<0.05）. Ovarian tissue was damaged， and the downward trend of follicles at all levels was similar to that in the low-dose VCD group. The litter number significantly decreased on D15 and D45. TGF-β and Smad2/3 protein levels increased （P<0.05，P<0.01）， and TGF-β mRNA increased on D45 （P<0.05）. ConclusionHigh-dose VCD is an ideal method for constructing a POI rat model， being effective， stable， and safe.

Background and objective Small cell lung cancer(SCLC)is known as recalcitrant cancer with high malignancy and heterogeneity.Immunotherapy has changed the treatment pattern of extensive-disease SCLC(ED-SCLC),but the beneficiary population is limited.Therefore,exploring new therapeutic strategies is an urgent clinical problem to be solved for SCLC.SCLC is characterized by highly active glycolytic metabolism and pyruvate kinase Ml(PKM1)is one of the isozymes of PK,an important rate-limiting enzyme in glycolysis pathway.Previous studies have shown that PKM1 is related to autophagy and drug sensitivity,however,how PKM1 regulates drug sensitivity in SCLC and its mechanism remain unclear.The aim of this study was to investigate the biological functions of PKM1 in SCLC,including its effects on proliferation,migra-tion,autophagy,drug sensitivity,and expression of neuroendocrine(NE)-related markers in SCLC.Methods Western blot was used to detect the expression level of PKM1 in SCLC cells.PKM1 gene-overexpressed SCLC cell lines were constructed by stable lentivirus transfection.Proliferation of cells and drug sensitivity were detected by MTT,and migration ability of cells was determined by Transwell.The level of autophagy was detected by flow cytometry.Western blot was used to determine the expression levels of NE-related proteins.Results PKM1 was differentially expressed among various SCLC cell lines,and was lower in H1092 cells(P＜0.01).Compared with the control group,there was no significant difference in proliferation level of PKM1 overexpressing H1092 cell,but the migration ability was significantly increased(P＜0.001),the drug sensitivity was re-duced,and the level of autophagy was inhibited(P＜0.001).Additionally,overexpression of PKM1 could upregulate the expres-sion of non-neuroendocrine(non-NE)-related proteins(P＜0.01)and decrease the expression of NE-related proteins(P＜0.01).Conclusion PKM1 was differentially expressed in SCLC cell lines,and high expression of PKM1 did not affect the prolifera-tion,but affected the migration of SCLC cells.PKM1 might affect drug sensitivity by inhibiting autophagy and regulating the expression of NE markers.These results provide a theoretical basis for exploring the role of PKM1 in SCLC.

Objective To summarize the experience of integrative palliative care at Peking Union Medi-cal College Hospital and provide a reference for promoting the integrative palliative care model.Methods Twenty cases receiving integrative palliative care at Peking Union Medical College Hospital were collected.The clinical characteristics,reasons for initiating integrative palliative care,the process of integrative palliative care,and feedback from these cases were summarized.Results Insomnia(11 cases,55％)and pain(9 cases,45％)were the most common symptoms requiring control in the 20 cases.The integrative palliative care team assisted in medical decision-making for 17 cases(85％),prepared end-of-life for 9 cases(45％),assisted in the transfer for 3 cases(15％),and provided comfort care for all the 20 cases(100％).Conclusions The integrative palliative care model can help alleviate suffering in end-of-life patients and provide support to patients'families and the original medical teams.This model is worth further promotion within class A tertiary hospitals.

Objective:To explore the symptom perception and coping experiences of patients with low anterior resection syndrome (LARS) after anus-preserving surgery for rectal cancer.Methods:This study adopted the phenomenological research method in qualitative research. From October 2022 to January 2023, purposive sampling was used to select 15 postoperative LARS patients with rectal cancer who underwent anus-preserving surgery and underwent outpatient follow-up or hospitalization at Henan Cancer Hospital as the research subject for semi-structured in-depth interviews. Colaizzi 7-step analysis method was used to analyze, summarize, and extract themes from interview data.Results:Four themes were extracted, including attitudes and emotional responses towards symptoms, daily activities influenced by symptoms, coping status with symptom management strategies, and the need for multidimensional support for symptoms.Conclusions:LARS patients after anus-preserving surgery for rectal cancer have many discomfort symptoms and are eager to receive support and assistance. Medical and nursing staff should pay attention to the complexity of patient symptom management and promptly conduct effective symptom assessment and intervention, providing patient-centered comprehensive supportive nursing, and improving their quality of life.

As a chronic inflammatory disease,incidence of atherosclerosis(AS)is increasing year by year,which seriously endangers human health.Regulatory T cells are unique subset of T cells with immunosuppressive effects.In recent years,a large number of studies have shown that regulatory T cells play an important role in development of AS.This article focuses on characteris-tics of regulatory T cells and their relationship with AS,in order to provide new ideas for treatment of AS.

Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of～260 million children in China.Beyond its physical manifestations,malocclusion also significantly influences the psycho-social well-being of these children.Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition,by mitigating the negative impact of abnormal environmental influences on the growth.Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development,ranging from fetal stages to the early permanent dentition phase.From an economic and societal standpoint,the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated,underlining its profound practical and social importance.This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children,emphasizing critical need for early treatment.It elaborates on corresponding core principles and fundamental approaches in early orthodontics,proposing comprehensive guidance for preventive and interceptive orthodontic treatment,serving as a reference for clinicians engaged in early orthodontic treatment.

Objective To establish and validate a biomechanical modeling method based on micro-magnetic resonance imaging(μMRI)and microstructure segmentation for noninvasively assessing microstructure behavior of the proximal femur.Methods Firstly,μMRI images were obtained from the femoral samples,and bone microstructures were segmented through regionized image processing to create the μMRI finite element model(μMRI model).Finite element analysis was performed utilizing a lateral fall posture simulation,and stress and strain were calculated.Secondly,the accuracy of μMRI image segmentation of bone microstructure was verified using micro-computed tomography(μCT),and the accuracy of μMRI model calculation result was verified using a finite element model constructed based on μCT(μCT model).Finally,the accuracy of bone surface strain calculated by μMRI model was verified through in vitro mechanical loading experiments simulating lateral falls and strain gauge measurements.Results The bone microstructure parameters BV/TV calculated by μMRI model and μCT model were significantly correlated(r=0.89,P<0.05).The maximum and minimum principal stress/principal strain percentiles calculated by μMRI model and μCT model were highly correlated(R2>0.9).The strain calculated by μMRI-FEM was highly correlated with the strain measured by mechanical experiments(R2=0.82).Conclusions The micro finite element model based on μMRI segmentation of bone microstructure can accurately characterize the micro-mechanical behavior of the proximal femur.This study provides an important tool for non-invasive assessment of hip femur microstructure degeneration and osteoporosis fracture risk in vivo.

Background Cognitive behavioral therapy(CBT)is a widely used and empirically supported psychotherapy method.In recent years,the localization of CBT related to culture has received increasing attention from Chinese scholars.However,there is still a lack of systematic research on the localization of CBT using idioms as materials.Objective To explore whether idioms reflect the mutual influence between the two core therapeutic elements of CBT(cognition and emotion)and to use them as CBT treatment tools among college students,so as to provide references for the localization of CBT.Methods Using the Xinhua Idiom Dictionary(second edition)published by the Commercial Press,a three-round manual screening method was used to select idioms that reflected the mutual influence between cognition and emotion in CBT.Based on the selected idioms,a survey questionnaire titled"survey on idiom understanding level"was developed.From August to October,2022,stratified sampling was conducted among college students from different majors and universities,and 815 valid questionnaires were obtained through the Questionnaire Star platform.By analyzing the understanding of each idiom among college students,idioms that could be used as CBT treatment tools were identified.Results In the Xinhua Idiom Dictionary(second edition),there were 13 idioms that reflected the influence of cognition on emotion and 5 idioms that reflected the influence of emotion on cognition.12 idioms could be used as CBT treatment tools,including 8 idioms that reflected the influence of cognition on emotion and 4 idioms that reflected the influence of emotion on cognition.Conclusion There may be idioms that reflect the mutual influence between the two core therapeutic elements of CBT(cognition and emotion)and these idioms can be attempted as a therapeutic tool for CBT among college students.