BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

ObjectiveTo systematically analyze the epidemiological characteristics and cause-of-death distribution among death cases with hepatitis C in Hongkou District of Shanghai, and to provide a scientific basis for optimizing healthcare resources allocation and targeted hepatitis C prevention and control measures. MethodsA retrospective cross-sectional study was conducted by integrating historical surveillance data from China Information System of Disease Prevention and Control and Shanghai Hongkou District Death Medical Registration System. Data on demographic characteristics, hepatitis C-related clinical and management records, and underlying causes of death for cases with hepatitis C between 2012 and 2024 in Hongkou District of Shanghai, were collected. Descriptive analyses were performed to analyze the epidemiological characteristics and cause-of-death distribution of death cases, and comparative analyses were conducted across different subgroups. ResultsA total of 204 hepatitis C-related deaths were identified in Hongkou District, Shanghai, from 2012 to 2024. The average age at death was (69.49±12.75) years The majority decedents were males (71.57%) and retired (73.53%). The top three underlying causes of death were malignant tumors (45.10%), cerebrovascular diseases (15.20%) and cardiovascular diseases (12.25%), collectively accounting for 72.55% of all deaths. Deaths attributed to hepatitis C accounted for 9.80% (20/204), with a mean age at death of (63.41±11.81) years. No statistically significant differences were observed in the proportion of hepatitis C-attributed deaths across different subgroups (all P>0.05). The proportion of premature deaths was 55.88% (114/204), with a mean age at death of (60.02±6.89) years. The proportion of premature deaths was higher among males (60.27%), laboratory-diagnosed patients (62.69%), patients with other liver diseases (72.06%), and those non-compliant with follow-up (70.97%) compared to their respective counterparts (all P<0.05). Additionally, homemakers /unemployed patients (100.00%) and employed patients (88.89%) had a significantly higher proportion of premature deaths compared to retired patients (42.67%) (P<0.001). There was a statistically significant difference in the distribution of causes of death between the premature death group and the non-premature death group (χ²=14.93， P=0.048). The top three causes of premature deaths were malignant tumors (50.00%), hepatitis C (12.28%) and cerebrovascular diseases (10.53%). Regarding the proportion of deaths occuring prematurely, other viral hepatitis had the highest percentage (75.00%), followed by diabetes mellitus (71.43%) and hepatitis C (70.00%). ConclusionThe majority of death cases with hepatitis C were males and retirees in Hongkou District, Shanghai. The leading cause of death was malignant tumors, while hepatitis C ranked as the fourth underlying cause, as well as served as the second leading cause of premature death following malignant tumors. Premature death was closely associated with gender, occupation, diagnostic classification, presence of other liver diseases, and follow-up compliance, highlighting the importance of enhanced health management and targeted interventions among high-risk groups.

Background: Adrenocortical hormones, particularly 11-oxygenated androgens, are pivotal in female reproductive health and fertility. Standardized detection kits and population-specific reference intervals are lacking in China, hindering related clinical applications. Methods: A HPLC-tandem mass spectrometry (HPLC-MS/MS) pipeline was developed, rigorously validated, and applied to simultaneously quantify corticosterone, cortisone, cortisol, 18-OH cortisol, androstenedione (A4), 11β-hydroxyandrostenedione (11-OH A4), dehydroepiandrosterone, and dehydroepiandrosterone sulfate in serum samples from 455 reproductive-aged women (18–45 yrs) in Guangxi, China. Age-dependent concentration trends were analyzed, and reference intervals stratified by age (2.5th to 97.5th percentiles) were established. Correlations with body-composition metrics, ethnicity, and the menstrual cycle were investigated. Results: The HPLC-MS/MS method demonstrated high precision (intra- and inter-assay CVs < 15%), accuracy, and sensitivity. All eight hormones exhibited significant age-related declines (P < 0.001 for seven hormones; P = 0.001 for 11-OH A4). Notably, 11-OH A4 levels were significantly lower in the 35–45-yr (3.05 nmol/L) and 25–34-yr (3.09 nmol/L) age groups than in the 18–24-yr (3.57 nmol/L) age group, whereas no significant difference was observed between the 35–45-yr and 25–34-yr age groups. Weak negative correlations were observed between the body mass index and corticosterone and cortisone levels, whereas ethnicity and the menstrual cycle showed no significant associations with hormone levels. Conclusions We developed an HPLC-MS/MS-based method for simultaneously quantifying eight adrenocortical hormones, including 11-OH A4, and defined age-specific reference intervals for reproductive-aged Chinese women. These findings advance the clinical utility of adrenocortical hormones in diagnosing and managing reproductive disorders.

ObjectiveThis study aimed to elucidate the mechanistic role of Staphylococcus aureus in the pathogenesis of atopic dermatitis (AD), a chronic inflammatory skin disorder characterized by pruritus and barrier dysfunction. A key focus was screening traditional Chinese medicine (TCM) active components with dual antibacterial and antipruritic efficacy, followed by systematic evaluation of their in vitro antibacterial activity. Additionally, a novel drug delivery system was constructed to enable localized efficient drug delivery, inhibiting S. aureus proliferation and alleviating its induced pruritus, thereby providing new strategies for targeted AD therapy. MethodsMale C57BL/6J mice aged 6-8 weeks (body weight 18-22 g) were used to establish an AD model via repeated oxazolone sensitization. On day 14, microbial samples were collected from the lesional area (1 cm²) using sterile cotton swabs, followed by vortex mixing, serial dilution, and plating on 5% sheep blood agar plates (incubated at 37°C for 24 h). Single colonies with complete transparent β-hemolytic zones were isolated and identified as vancomycin-intermediate S. aureus (VISA) via 16S rRNA sequencing. An S. aureus mono-infection animal model was then established by applying gauze saturated with bacterial suspension (McFarland turbidity 0.1) to the nape and back skin of mice. The pruritic phenotype and inflammatory cell infiltration induced by S. aureus were evaluated using comprehensive approaches including behavioral assays (e.g., scratching frequency recording), hematoxylin-eosin (HE) staining, and toluidine blue staining. The in vitro antibacterial efficacy of the TCM monomer pseudolaric acid B (PAB) and double network hydrogel (DN) was separately assessed by disk diffusion assay, while the minimum inhibitory concentration (MIC) of PAB was determined via broth dilution method. Further validation of the pharmacodynamic characteristics of the composite system (PAB@DN, composed of PAB and DN) was conducted through behavioral assays, HE staining, and dermatitis scoring, with its drug release profile evaluated by mass spectrometry analysis. Based on scratching behavioral analysis and dermatitis scoring, the optimal ratio and concentration of PAB@DN were optimized. ResultsThe S. aureus load in AD lesional tissues was significantly higher than in normal skin ((5.3±0.33)×10⁶ CFU vs. (3.6±0.26)×10⁷ CFU, P<0.001). In the S. aureus mono-infection group, mice exhibited a 6.7-fold increase in scratching frequency compared to the control group. HE staining revealed marked epidermal thickening ((10.4±2.39) μm vs. (85.6±1.95) μm, P<0.000 1), and toluidine blue staining showed a 23-fold increase in mast cell degranulation. Pseudolaric acid B exhibited a significant concentration-dependent inhibitory effect onS. aureus growth, with its in vitro antibacterial effect being 57% that of the antibiotic cefepime (inhibition zone diameter: PAB (1.885±0.036) cm vs. cefepime (3.636±0.005) cm, P<0.000 1) and a minimum inhibitory concentration (MIC) of 1 g/L. The carrier double network hydrogel (DN) itself lacked direct antibacterial activity (no significant difference in inhibition zone diameter compared to the control) but effectively ameliorated the dry symptoms of AD-like lesions. The PAB@DN composite system demonstrated a synergistic effect compared to individual components, resulting in a 50% reduction in scratching behavior, an 86% decrease in dermatitis score, and a 60% reduction in epidermal thickening. It also reduced the S. aureus load in mouse skin by approximately 34%, with the optimal effective formulation being PAB at 1 g/L loaded onto DN. ConclusionS. aureus colonization plays a critical driving role in the onset and progression of AD. Using an S. aureus infection model, this study confirmed that the pseudolaric acidB-hydrogel composite delivery system (PAB@DN) can effectively alleviate S. aureus-induced pruritus and skin damage, providing experimental evidence for microbiota-targeted therapy of AD.

Objective To investigate the toxic effects of combined yttrium and lead exposure on liver and kidney functions in male Sprague-Dawley (SD) rats. Methods Adult male specific pathogen-free SD rats were randomly divided into four groups. Rats in the low-, medium-, and high-dose groups were co-administered with yttrium acetate (10.0, 50.0, and 100.0 mg/kg body weight, respectively) and lead acetate (4.0, 20.0, and 40.0 mg/kg body weight, respectively) by intragastric gavage, once per day for 28 consecutive days. Rats in the control group received an equal volume of deionized water. Yttrium and lead levels in whole blood, liver, and kidney tissues of the rats were measured using inductively coupled plasma mass spectrometry. Serum index of liver and kidney function were measured by a double reagent method, and histopathological changes in the liver and kidney were observed. Results The body weights of rats in all the three exposure groups were lower than those in the control group from day 14 of exposure until the end of exposure (all P<0.05). Body weight gain of rats was observed only in the low-dose group at day 28, whereas no body weight gain was observed throughout the exposure period in the medium- and high-dose groups. Histopathological examination showed dose-dependent liver and kidney injuries in rats of the three exposure groups compared with the control group. Specifically, the liver exhibited widening of intercellular spaces and increased inflammatory cell infiltration, while the kidney showed increased tissue hemorrhage and increased damage to glomeruli and renal tubules. Lead levels in whole blood, liver, and kidney tissues of the rats were higher than yttrium levels in all the three exposure groups (all P<0.05). Blood yttrium levels in rats of the high-dose group were higher than those in the other three groups (all P<0.05), and yttrium levels in the liver and kidney tissues of the three exposure groups were higher than those in the control group (all P<0.05). Lead levels in whole blood, liver, and kidney tissues of the rats increased with increasing exposure dose (all P<0.05). At the end of exposure, the kidney organ coefficient of rats in the high-dose group was higher than those in the other three groups (all P<0.05). The serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) ratio of rats in the high‑dose group was lower than that in the control group (P<0.05). The serum urea and uric acid levels in the medium‑ and high‑dose groups were lower than those in the control group (both P<0.05). The serum cystatin C level in the high‑dose group was higher than that in the control group (P<0.05). Blood yttrium and blood lead levels were each negatively correlated with serum ALT/AST ratio, serum urea nitrogen, and uric acid levels (both P<0.05). Both yttrium and lead levels in liver tissue were each negatively correlated with serum ALT/AST ratio (all P<0.05). Both yttrium and lead levels in kidney tissue were each negatively correlated with both serum urea nitrogen and uric acid levels (all P<0.05), and each positively correlated with serum cystatin C levels (both P<0.05). Conclusion Co-exposure to yttrium and lead induces dose‑dependent hepatotoxicity and nephrotoxicity in male SD rats. Lead exhibits a more pronounced accumulation effect and contributes more substantially to the observed toxicity.

Objective:To analyze the prevalence and risk factors of blindness and moderate to severe visual impairment among Han and Kazakh residents aged 50 years and older in Tacheng City, Xinjiang Uygur Autonomous Region.Methods:This study is a cross-sectional survey conducted using cluster random sampling from October 2015 to June 2018 in Emin County, Tacheng City, Xinjiang Uygur Autonomous Region. The study included individuals aged 50 years and older to survey blindness and moderate to severe visual impairment. Ophthalmological examinations combined with questionnaires were conducted to gather basic information. The data collected from the questionnaires included general demographic information and health conditions. The results of the eye examinations were used to diagnose a total of 12 risk factors including cataracts, glaucoma, pterygium, suspected glaucoma, glaucoma, and refractive errors. These risk factors were analyzed in relation to blindness and moderate to severe visual impairment. Univariate analysis was conducted first, followed by logistic regression to identify the significant factors.Results:A total of 2 114 patients were included in the final analysis, among which the prevalence of moderate to severe visual impairment was 18.54% (392/2 114), and the prevalence of blindness was 2.74% (58/2 114). Univariate analysis showed that blindness and moderate to severe visual impairment were associated with age ( χ2 = 32.97, P < 0.05), hypertension ( χ2 = 3.48, P < 0.05), age-related cataract ( χ2 = 17.43, P < 0.05), glaucoma ( χ2 = 3.90, P < 0.05), macular degeneration ( χ2 = 16.04, P < 0.05), diabetes ( χ2 = 3.09, P < 0.05), pterygium ( χ2 = 2.57, P < 0.05), and fundus arteriosclerosis ( χ2 = 2.31, P < 0.05). Multivariate logistic regression analysis indicated that moderate to severe visual impairment was correlated with age (50 to < 60 years: OR = 2.91, 95% CI: 0.44-13.45; 60 to < 70 years: OR = 3.52, 95% CI: 0.73-8.77; 70 to < 80 years: OR = 4.31, 95% CI: 0.85-8.96), ethnicity ( OR = 4.45, 95% CI: 0.56-5.95), sex ( OR = 0.47, 95% CI: 0.34-0.64), age-related cataract ( OR = 1.67, 95% CI: 1.05-2.65), glaucoma ( OR = 2.97, 95% CI: 1.67-5.30), and coronary heart disease ( OR = 2.56, P < 0.05). Blindness was correlated with age (70-79 years: OR = 1.54, 95% CI: 1.12-2.11), sex ( OR = 0.67, 95% CI: 0.34-0.64), glaucoma ( OR = 1.65, 95% CI: 0.42-6.49), diabetes ( OR = 2.05, 95% CI: 1.35-3.09), and coronary heart disease ( OR = 1.92, 95% CI: 1.07-3.43). Among these, age (70-79 years), glaucoma, diabetes, and coronary heart disease were identified as risk factors for blindness, while sex was observed as a protective factor against blindness in this region. Based on univariate and multivariate analyses as well as clinical practice, it was concluded that age (50 to < 60 years: OR = 4.42, 95% CI: 1.31-14.92; 60 to < 70 years: OR = 4.49, 95% CI: 1.70-11.84; 70 to < 80 years: OR = 3.19, 95% CI: 1.29-7.87), age-related cataract ( OR = 1.67, 95% CI: 1.05-2.65), and glaucoma ( OR = 2.97, 95% CI: 1.67-5.30) were identified as significant risk factors for moderate to severe visual impairment. Glaucoma ( OR = 1.65, 95% CI: 0.42-6.49) and diabetes ( OR = 2.05, 95% CI: 1.35-3.09) were identified as the main risk factors for blindness in this region (both P < 0.05). Conclusions:In Tacheng City, Xinjiang Uygur Autonomous Region, the prevalence rates of moderate to severe visual impairment and blindness among Han and Kazakh residents are relatively high. Age-related cataracts and glaucoma are the primary causes, while age and diabetes are the main risk factors.

Objective To explore the predictive value of dose surface histogram(DSH)in image guided radiotherapy(IGRT)for radiotherapy-induced acute radiation proctitis(ARP)in cervical cancer(CCA).Methods Totally 380 patients with CCA IGRT admitted to some hospital from May 2019 to May 2023 were selected prospectively and randomly divided into a control group(n=1 80)and an experimental group(n=200).The patients in the 2 groups were followed up and the incidence rates of ARP were counted,and rectal dose distribution was evaluated using dose volume histogram(DVH)in the control group and DSH in the experimental group.The predictive values of DVH and DSH for ARP were evaluated and compared using ROC curves.Statistical analysis was performed using SPSS 21.0 software.Results The two groups did not have statistically significant difference in the incidence rate of ARP(P＞0.05),while there were significant differences in the evaluation indicators of the rectal dose distribution(P＜0.05).V40,V50,S40 and S50 proved to have low predictive values for grade Ⅰ-Ⅳ ARP with AUC 0.700(P＜0.05);V60 and S60 had moderate predictive values for grade Ⅰ-Ⅳ ARP with AUC greater than 0.700 and less than or equal to 0.900(P＜0.05);V70,V78,S70 and S7s showed high predictive values for grade Ⅰ-Ⅳ ARP with AUC higher than 0.900(P＜0.05).Delong's test results indicated that DVH and DSH had no significant differences in AUC when used to predict gradeⅠ-Ⅳ ARP(allP＞0.05).Conclusion DSH is essentially the same as DVH when used for the prediction of grade Ⅰ-Ⅳ ARP due to CCA IGRT,and thus can be used for the supplementation and optimization of radiotherapy planning systems.[Chinese Medical Equipment Journal,2025,46(3):48-53]

Objective To explore the biological effects and changes of metabolites of Guilu erxian glue(GLE)in vivo in the pre-vention and treatment of postmenopausal osteoporosis(PMO),based on non-targeted metabolomics.Methods Fifty SD female rats were divided into five groups using the random number table method:sham group,model group(OVX),and low-,medium-,and high-dose GLE(GLE-L,GLE-M and GLE-H)groups,with ten mice in each group.After 1 week of modeling,the drug was given by gavage,and samples were collected 8 weeks later.Bone microstructure was detected by MicroCT,bone metabolism-related indices were analyzed by immunohistochemistry(IHC),and a serum metabolite atlas was constructed using the LC-MS/MS technique to observe the distribution differences of metabolites and related pathways.Results The MicroCT results showed that GLE could increase the percentage of bone trabeculae and restore bone microstructure(P<0.05,GLE-M group vs.OVX group).IHC analysis showed that GLE could increase Runx2 expression in femur(P<0.05,GLE-M group vs.OVX group).There were four co-regulated metabolites in the sham group,GLE-H group,and OVX group,including 3-(3-methoxyphenyl)propionic acid,acetamide,Equol,and 1-oleoacyl-SN-glycerol-3-phosphocholine,which showed high expression in the sham group,low expression in the OVX group,and high expression in the GLE-M group.The KEGG pathway result showed that the main pathways involved between the sham group and OVX group were steroid hormone biosynthesis and cortisol synthesis and secretion.Tryptophan metabolism and phenylalanine metabolism were observed in the GLE group and OVX group.Conclusion GLE may prevent PMO by regulating metabolites in the body.

Aim To investigate the effect of p-AMPK activity on autophagy in different subtypes of MDA-MB-231(triple-negative breast cancer cells)and MCF-7(estrogen receptor-positive cells)and its regulatory mechanism.Methods MDA-MB-231 cells were trea-ted with EBSS,Baf-A1,and EBSS+Baf-A1 for four hours,and MCF-7 cells for eight hours.The effects of autophagy on cell proliferation and apoptosis were ob-served,mitochondrial morphology was examined,and the expression of autophagy markers LC3B,P62,LAMP1,TOM20,AMPK,p-AMPK,ULK1,and Bec-lin1/VPS34 proteins was detected.The autophagy pathway was validated by inhibiting AMPK activity.Results Breast cancer cells underwent autophagy af-ter starvation induction(EBSS),with inconsistent au-tophagy processes observed in different subtypes of breast cancer cells.Autophagy inhibited cell prolifera-tion.In MDA-MB-231 cells,autophagy led to an in-crease in p-AMPK levels and a decrease in ULK1 lev-els,initiating autophagy through p-AMPK activation of ULK1.In MCF-7 cells,both p-AMPK and ULK1 levels decreased after autophagy,suggesting that autophagy might not be mediated by p-AMPK activation.Conclu-sions MDA-MB-231 cells primarily initiate autophagy by directly activating ULK1 by p-AMPK,independent of the MTOR pathway.In MCF-7 cells autophagy might be triggered by inhibiting MTOR through AMPK activity or directly activating MTOR through other up-stream factors.Regulating p-AMPK activity based on the autophagy pathways in different cell subtypes could enable more precise targeting and treatment of different types of breast cancer.