ObjectiveBiochemistry and Molecular Biology, a discipline that elucidates life phenomena at the molecular level, serves as a core foundational course in medical education. It provides the theoretical basis for studying other basic and clinical medical subjects, as well as for understanding pathogenesis, disease diagnosis, and treatment. However, its complex content and highly abstract concepts have posed a dual challenge to traditional teaching models: “inefficient instruction” and “inadequate learning outcomes”. Within limited classroom hours, how to engage students and stimulate their intrinsic motivation, and how to help them recognize, understand, and develop a passion for biochemistry from the perspective of the discipline’s essence, have long been key focuses of curriculum research. MethodsUsing the lipid metabolism chapter as an example, this study employs “Rain Classroom”, a generative artificial intelligence (AI)-assisted platform, to support education in four dimensions: teaching, learning, evaluation, and research. In teaching, it assists instructors through virtual experiments, lesson preparation support, knowledge mapping, and assignment design. For learning, it serves as an intelligent study assistant for students, providing automated assignment review, enabling educational resource sharing, and facilitating personalized learning pathways. In evaluation, the platform automates assignment grading, analyzes student performance data, and offers diagnostic feedback and teaching recommendations. In research, it aids educators in collecting and analyzing teaching data, as well as searching for and summarizing relevant literature. ResultsThe results indicate that an educational model integrating teacher-led instruction, student-centered learning, and generative AI assistance significantly enhances teaching quality, students’ self-directed learning abilities, and knowledge mastery. Furthermore, with the support of generative AI, curriculum-based ideological education—focusing on cutting-edge disciplinary advances and topical medical issues—helps cultivate students’ medical spirit of “honoring life and healing the wounded”, thereby fostering the establishment of appropriate professional values. Finally, while generative AI presents both opportunities and challenges for higher education, this study also analyzes potential risks in its teaching applications, emphasizing the need for both instructors and students to avoid over-reliance and to ensure that technological tools consistently serve the fundamental goals of education. ConclusionThis study demonstrates that integrating generative AI, specifically via the “Rain Classroom” platform, can effectively enhance biochemistry education. By supporting teaching, learning, evaluation, and research, this approach improves both educational effectiveness and student outcomes. It also facilitates the incorporation of cutting-edge knowledge and professional ethics, nurturing a patient-centered mindset. Additionally, the study addresses potential implementation risks to ensure that such technological tools remain aligned with the core purpose of education.

Objective To summarize the diagnostic ideas, clinical characteristics and treatment methods of the rupture of pseudoaneurysm in the pararenal artery, so as to provide reference for the management of such condition.Methods The diagnosis and treatment process of a patient with massive retroperitoneal hemorrhage due to rupture of pseudoaneurysm in the left pararenal artery admitted to the Affiliated Hospital of Yan'an University were reported, and relevant literature was retrieved to summarize the etiology, pathogenesis, diagnosis and treatment of this disease.Results The patient was a 49-year-old male who presented with sudden onset of lumbar and abdominal pain.After admission, enhanced computed tomography (CT) scan indicated a cystic lesion in the left kidney, along with fluffy high-density and fluidic density shadows around the kidney.There was extensive extravasation of contrast agent in the lower polar artery of the left kidney, with rupture shadows, retention of contrast agent, and the extent of extravasation expanding in the venous phase and delayed phase, suggesting that the renal artery or pararenal artery had ruptured and bled.After consultation by the Department of Intervention, an urgent superselective left renal artery embolization procedure was performed.During the operation, angiography showed the “jetting sign” in the arterial phase, and the stenosis at the neck of the tumor.In the delayed phase, the contrast agent was retained accompanied with the “chimney sign”, which was consistent with the characteristics of a pseudoaneurysm.The final diagnosis was rupture and bleeding of a pseudoaneurysm of the left pararenal artery, along with the formation of a hematoma, as well as accumulation of blood and fluid in the abdominal and pelvic cavities.The patient recovered well after surgery.After a follow-up of 6 months, CT scan showed that the hematoma was basically absorbed and there were no obvious abdominal pain or other discomforts.Conclusion Rupture of pseudoaneurysm in the pararenal artery is rare in clinical practice.Treatment should be tailored to the anatomical features and the patients' condition.Multidisciplinary collaboration, precise imaging evaluation, and the application of interventional techniques can achieve efficient diagnosis and treatment, and protect the renal function to the greatest extent.

Sumoylation is a newly discovered post-translational modification, in which a small ubiquitin-like modifier (SUMO) is covalently conjugated to a lysine residue in a target protein. This provides an efficient way to modulate the activity, stability and subcellular localization of a wide variety of substrates. Sumoylation plays a key role in the occurrence and development of type 2 diabetes mellitus (T2DM). This paper addresses the relationship between sumoylation and T2DM in regulation of pancreatic β-cell function, the metabolic order in skeletal muscles, liver and other organs and diabetes-associated complications. A deeper knowledge of sumoylation may enable us to better understand the pathogenesis of T2DM and sumoylation system at the molecular level, which can help provide new ideas for the early diagnosis and subsequent treatment of T2DM and its associated complications.

Objective To analyze the burden and epidemic trends of gastric cancer in China from 1990 to 2021, and to provide a scientific basis for the formulation of effective prevention and control strategies. Methods　Data from the 2021 Global Burden of Disease (GBD) database were used to extract the number of the incidence, prevalence, and death cases, as well as the disability-adjusted life years (DALY) for gastric cancer in China from 1990 to 2021. The corresponding crude rates and age-standardized rates were calculated. The Joinpoint regression model was employed to analyze the trends in the burden of gastric cancer, and a comprehensive examination was conducted from multiple dimensions including age, gender, and time. Results From 1990 to 2021, the age-standardized incidence rate (ASIR) of gastric cancer in China decreased from 48.03 per 100,000 to 29.05 per 100,000, the age-standardized prevalence rate (ASPR) decreased from 67.17 per 100,000 to 57.23 per 100,000, the age-standardized mortality rate (ASMR) decreased from 46.05 per 100,000 to 21.51 per 100,000, and the age-standardized DALY rate (ASDR) decreased from 1181.61 per 100,000 to 501.26 per 100,000. The AAPCs of ASIR, ASPR, ASMR, and ASDR were -1.61%, -0.50%, -2.44%, and -2.75%, respectively. The incidence, prevalence, mortality and DALY rates showed a trend of increasing first and then decreasing with age. Although females had higher incidence, prevalence, mortality, and DALY numbers in the older age groups, males exhibited higher crude rates across all age groups. Conclusion　The overall disease burden of gastric cancer in China showed a downward trend from 1990 to 2021, and men and middle-aged and elderly people are the key populations for prevention and control efforts.

Objective: To investigate the association between overweight, obesity, central obesity and hypertension, so as to provide the basis for formulating targeted hypertension prevention and control strategies. Methods: Permanent residents aged ≥18 years were selected in Wenzhou City, Zhejiang Province from June 2023 to August 2024 by a multistage cluster random sampling method. Data on demographic information, lifestyle, height, weight, waist circumference (WC), blood pressure, and blood biochemical indicators were collected through questionnaire surveys, physical examinations, and laboratory tests. The prevalence of hypertension was calculated and standardized using the data of the Sixth National Population Census in 2010. Body mass index (BMI) was calculated to determine overweight and obesity, while WC was used to identify central obesity. The association between overweight, obesity, central obesity and hypertension were analyzed using multivariable logistic regression models. Results: A total of 38 593 residents were surveyed, including 19 481 (50.48%) males and 19 112 (49.52%) females. The median age was 46.00 (interquartile range, 26.00) years. The rates of overweight, obesity, and central obesity were 32.74% (12 634 individuals), 10.27% (3 963 individuals), and 27.87% (10 755 individuals), respectively. There were 11 813 cases of hypertension, with a prevalence and standardized prevalence of 30.61% and 24.41%, respectively. Multivariable logistic regression analysis showed that after adjusting for demographic information, lifestyle, diabetes and dyslipidemia, the likelihood of hypertension in the overweight and obesity groups was 1.927 (95%CI: 1.815-2.045) times and 3.724 (95%CI: 3.404-4.073) times that of the normal BMI group, respectively. The likelihood of hypertension in the central obesity group was 2.346 (95%CI: 2.214-2.486) times that of the normal WC group. The likelihood of hypertension in the central obesity only, overweight only, overweight with central obesity, obesity only and obesity with central obesity groups was 1.586 (95%CI: 1.391-1.809), 1.704 (95%CI: 1.582-1.835), 2.433 (95%CI: 2.254-2.626), 1.768 (95%CI: 1.424-2.194), and 4.466 (95%CI: 4.053-4.921) times that of the normal BMI and WC group, respectively. Conclusions Overweight, obesity and central obesity were all associated with hypertension among adult residents. The highest likelihood of hypertension was observed among adult residents with both general obesity and central obesity.

Objective To analyze the epidemiological characteristics of lung cancer death in Gansu Province, and to provide a theoretical basis for formulating the prevention and control measures of lung cancer. Methods The lung cancer death data from national monitoring sites in Gansu Province from 2014 to 2023 were selected. Excel2013 and SPSS17.0 were used to calculate lung cancer mortality, standardized mortality, potential years of life lost (PYLL), potential years of life lost rate, standardized potential years of life lost rate, and average years of life lost (AYLL). The annual percent change (APC) of the crude lung cancer mortality rate and standardized mortality rate was calculated using Joinpiont 4.8.0.1 software. The mortality difference decomposition method was used to analyze demographic and non-demographic factors. Results From 2014 to 2023, the crude mortality rate of lung cancer among the residents of the monitoring sites in Gansu Province showed an increasing trend. The mortality rate of males was higher than that of females. The mortality rate in urban areas was higher than that in rural areas. The population structure was the main factor leading to the increase of lung cancer mortality rate in urban areas, while other non-demographic factors were the main factors leading to the increase of lung cancer mortality rate in rural areas. The crude lung cancer mortality rate was low at the age of < 30, and then the mortality rate increased with age. Lung cancer PYLL was higher in males than in females, and AYLL was higher in females than in males. Conclusion The mortality rate of lung cancer in the monitoring sites in Gansu Province is on the rise. The urban areas and male population are the key areas and groups for intervention. It is suggested to further strengthen the early screening and intervention of lung cancer to reduce the mortality rate of lung cancer.

Objective To explore the effects of different glucose concentrations on the synthesis and secretion of bone collagen in osteoblasts and the impact of diabetes on bone quality in mice.Methods(1)Primary osteoblasts were extracted from the skulls of neonatal mice via collagenase digestion and cultured in four groups under different glucose concentrations:normal glucose(5.5 mmol/L),moderate glucose(11.5 mmol/L),moderate-high glucose(16.5 mmol/L),and high glucose(25 mmol/L).EdU staining was performed to evaluate cell proliferation,while the Transwell assay was used to assess cell migration.Immunofluorescence and Western blotting were performed to detect and quantitatively analyze the content of type Ⅰ collagen(Col-1).Alizarin red S(ARS)staining and alkaline phosphatase(ALP)staining were applied to assess the effects of different glucose concentrations on osteogenic differentiation.(2)Six-week-old male C57BL/6 mice were randomly divided into control group and model group(5 in each group).The model group was fed a high-fat diet for 4 weeks followed by streptozotocin(STZ)injection to establish a diabetic mouse model.The osteogenic differentiation capacity of primary osteoblasts from both groups was assessed.(3)Micro-computed tomography(Micro-CT)was employed to analyze femoral bone mineral density(BMD),bone volume/tissue volume(BV/TV),trabecular number(Tb.N),and trabecular separation(Tb.Sp).Three-point bending test was conducted to evaluate mechanical parameters including maximum load,Young's modulus,fracture energy,and stiffness.RT-qPCR was employed to assess the expression of osteogenic differentiation genes(Alp,Opn,Col1a1,and Lox).Masson staining and Mallory staining were used to evaluate Col-1 content in trabecular bone.Results(1)EdU and Transwell assay results demonstrated that with the gradual increase in glucose concentration,the proliferation and migration abilities of osteoblasts were significantly decreased(P<0.001),and the protein expression levels of Col-1 and lysyl oxidase(LOX)were significantly reduced(P<0.01 or P<0.001).ARS and ALP staining revealed that calcium salt deposition and ALP activity in osteoblasts were significantly decreased with increasing glucose concentration(P<0.05 or P<0.001).(2)Compared with control group,mice in model group exhibited typical"three polies and one weight loss"symptoms(polyuria,polydipsia,polyphagia,and weight loss)of diabetes,and ARS and ALP staining showed a significant reduction in osteoblasts(P<0.001).(3)Micro-CT and three-point bending test results indicated that,compared with control group,mice in model group showed microarchitectural deterioration of bone,decreased Tb.N,increased Tb.Sp,and significantly reduced maximum load,Young's modulus,fracture energy,and stiffness(P<0.05).RT-qPCR results showed that the relative mRNA expression levels of osteogenic differentiation genes(Alp,Opn,Col1a1,and Lox)were significantly decreased in model group compared with control group(P<0.01 or P<0.001).Masson and Mallory staining indicated a significant reduction in collagen content in model group compared with control group(P<0.01).Conclusions High-glucose environment inhibits osteoblast proliferation,differentiation,and migration.Diabetic mice exhibit reduced bone quality and increased bone fragility,potentially mediated by decreased lysyl oxidase and collagen levels.

Objective To investigate the mechanism of hippocampal neuronal plasticity of newborn neurons in the hippocampus by which exercise improves the fear and anxiety symptoms of post-traumatic stress disorder(PTSD).Methods Totally 40 C57BL/6J male mice were randomly divided into by control group(Ctrl)and PTSD group,the PTSD group was divided into a no-exercise group(PTSD),a low-intensity exercise group(L)and a high-intensity exercise group(H).The PTSD model mice were constructed by combining conditioned plantar-foot shock(CF)and single-session sustained stress(SPS).After the exercise intervention,the fear and anxiety levels of the mice were assessed using the conditioned fear test and the elevated cross maze test;Subsequently,the densities of the newborn mature neurons in dentate gyrus(DG)of hippocampus were detected by immunofluorescent double-labelling staining,and the newborn neuron morphology was marked by injecting retrovirus pRetro-U6-EF1-EGFP-3xFLAG-WPRE in DG of hippocampus to observe its morphology.The morphology of the newborn neurons was labelled to observe their dendritic length and the number of branch points;Meanwhile,the concentration level of adiponctin(APN)in the hippocampal area was determined by ELISA.Results The result showed that both high and low-intensity exercise interventions significantly reduced the freezing time of PTSD mice in the conditioned fear test,and in the elevated cross maze experiment,the residence time and the number of entries in the open arm of the mice in the H group increased significantly compared with those in the PTSD group,while the residence time and the number of entries in the closed arm were significantly reduced.In addition,both high and low-intensity exercise interventions significantly increased the surface density and dendritic length of newborn mature neurons in the hippocampal DG region of PTSD mice,and high-intensity exercise significantly increased the number of dendritic branching points,and the density of newborn mature neurons in the H group was more significantly increased compared with that in the L group.At the same time,the hippocampal APN concentration increased significantly in both L and H groups compared with the PTSD group,and it was more significant in the H group.Conclusion Exercises have an ameliorative effect on anxiety and fear symptoms in PTSD mice,and at the same time,it can increase hippocampal neuroplasticity and adiponctin secretion in PTSD mice,suggesting that the improvement of fear and anxiety symptoms in PTSD by exercise may be related to the increase of hippocampal neuroplasticity and APN secretion,and the improvement effect is better with high-intensity exercise.

Objective The aim of this study was to characterize the basic molecular and biochemical parameters for a cyclophilin protein in Cryptosporidium parvum called CpCyP1.Methods CpCyP1 expression patterns during the parasite life cycle were evaluated using qRT-PCR with total RNA isolated from different developmental stages of C.parvum.Native CpCyP1 protein in sporozoites was detected using western blot.The localization of CpCyP1 was performed using the immunofluorescence assay,with an affinity-purified rabbit polyclonal antibody against a synthetic peptide.The peptidyl-prolyl cis-trans isomerase(PPIase)activity of His-tagged recombinant CpCyP1 was evaluated using absorbance colorimetry,and the effect of cyclosporin A(CsA)on the activity of CpCyP1 was determined.Results CpCyP1 was expressed in all parasite developmental stages,whereas CpCyP1 was present mainly in the cytosol of sporozoites,meronts,and gamonts.CpCyP1 displayed Michaelis-Menten kinetics towards N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide for its PPIase activity(Km=456.4 μmol/L;Vmax=1.981 U).CsA inhibited PPIase activity,showing lower micromolar inhibitory activity and binding affinity(Kd=5.122 μmol/L;IC50=1.004 μmol/L).Conclusions These results imply that CpCyP1 in the parasite may be the target for the previously reported anti-cryptosporidial efficacy of CsA and suggest that C.parvum cyclophilins could be evaluated as candidate drug targets.

Osteoporosis is a globally prevalent metabolic bone disease,with bone homeostasis imbalance being its key pathogenic mechanism.Over the years,studies on the relationship between ambient temperature and bone health have shown heterogeneous results due to different conditions.Epidemiological studies indicate that the incidence of osteoporotic fractures varies geographically and climatically.People in cold regions experience earlier bone loss,and high-latitude cold areas are high-risk zones for hip fractures.Osteoporosis is more prevalent in North China that in South China.Additionally,the early stage of the disease is insidious,highlighting the need for early prevention and treatment across the entire population.Mechanistically,low temperatures affect acral bone development,reduce bone blood circulation,cause degradation of bone microstructure,and increase osteocyte apoptosis,thereby promoting bone resorption and reducing bone mass.This review aims to provide data and new lines of thought for the early precise prevention and effective clinical treatment of osteoporosis in cold regions.