BACKGROUND:Several observational studies have found a close relationship between thyroid function levels and sarcopenia,but the causal relationship between thyroid function levels and the onset of sarcopenia is not yet clear. OBJECTIVE:To investigate the causal relationship between thyroid function levels and sarcopenia using a two sample Mendelian randomization method. METHODS:A two sample Mendelian randomization analysis was conducted using genome-wide association study data on thyrotropin,free triiodothyronine,free tetraiodothyronine,subclinical hyperthyroidism,subclinical hypothyroidism,and four related phenotypes of sarcopenia-lefthand grip strength,right hand grip strength,limb lean mass,and gait speed.The inverse-variance weighted method,weighted median method,simple mode method,weighted median estimator method,and MR Egger regression method were used as analysis methods,while heterogeneity test,pleiotropy test,MR-PRESSO,leave-one-out method,funnel plot and other methods were used for sensitivity analysis. RESULTS AND CONCLUSION:Elevated levels of thyroid-stimulating hormone increased left-(β=0.02,SE=0.01,P=0.01)and right-handed grip strength(β=0.02,SE=0.01,P=0.01),an increase in free triiodothyronine decreased left-(β=-0.06,SE=0.02,P=9.5×10-5)and right-handed grip strength(β=-0.07,SE=0.02,P=9.3×10-5),and subclinical hyperthyroidism decreased gait speed(β=-4.4×10-3,SE=1.7×10-3,P=0.01).The sensitivity analysis results were basically consistent with the main analysis results.To conclude,an increase in thyroid-stimulating hormone is a protective factor for sarcopenia,and elevation of free triiodothyronine and subclinical hyperthyroidism may increase the risk of sarcopenia.

Objective To explore the efficacy of a model combining clinicopathological characteristics and multiparametric MRI features for predicting BRCA-mutated breast cancer(BC).Methods A total of 256 BC patients were retrospectively selected and divided into BRCA mutation group(116 cases)and BRCA wild group(140 cases)based on the BRCA results.Chi-square tests or independ-ent sample t-tests were used to compare the differences in clinicopathological characteristics and multiparametric MRI features between the BRCA mutation group and the wild group.Risk factors for BRCA-mutated BC were identified through univariate and multivariate logistic regression ananlyses,and a combined predictive model was constructed.Receiver operating characteristic(ROC)curve was used to ana-lyze the diagnostic efficacy of the model.Results There were statistically significant differences in T stage,human epidermal growth factor receptor 2(HER-2),Ki-67,non-mass enhancement,enhancement pattern,time-signal intensity curve(TIC)type,and apparent diffusion coefficient(ADC)values between the BRCA mutation group and the wild group.Univariate logistic regression analysis showed that T stage,HER-2,Ki-67,non-mass enhancement,enhancement pattern,TIC type,and ADC values were risk factors for BRCA-mutated BC(P<0.05).Multivariate logistic regression analysis revealed that T stage,HER-2,Ki-67,enhancement pattern,and TIC type were independent risk factors for BRCA-mutated BC(P<0.05).The combined model incorporating T stage,HER-2,Ki-67,enhancement pattern,and TIC type had the best diagnostic efficacy in predicting BRCA-mutated BC,with an area under the curve(AUC)of 0.751.Conclusion The combined model integrating T stage,HER-2,Ki-67,enhancement pattern,and TIC type has good efficacy in predicting BRCA-mutated BC.

Objective To explore the diagnostic value of a combined model based on clinicopathological and MRI features in BRCA-mutated ovarian cancer.Methods The data of 132 patients with ovarian cancer who underwent pathology and BRCA gene tes-ting were analyzed retrospectively,including 52 cases of BRCA mutation group and 80 cases of BRCA wild group.The differences of MRI features and clinicopathological features between BRCA mutation group and BRCA wild group were compared.Binary logistic regression was used to construct a joint prediction model and analyze its diagnostic efficiency.Results There were significant differ-ences in cytokeratin 7(CK7),estrogen receptor(ER),Ki-67 and lymphovascular invasion(LVI)between the BRAC mutation group and the BRAC wild group(P＜0.05).Univariate analysis showed that CK7,ER,Ki-67,LVI and the apparent diffusion coefficient(ADC)value of the cystic part of tumor were risk factors for BRCA-mutated ovarian cancer.The combined model based on CK7,ER,Ki-67,LVI,and the ADC value of the cystic part of tumor for the diagnosis of BRCA-mutated ovarian cancer had an area under the curve(AUC)of 0.765.Conclusion CK7,ER,Ki-67,LVI and the ADC value of the cystic part of tumor are risk factors for BRCA-mutated ovarian cancer.The combined model based on the above characteristics demonstrates good diagnostic efficacy for BRCA-mutated ovarian cancer.

Objective To explore the efficacy of a model combining clinicopathological characteristics and multiparametric MRI features for predicting BRCA-mutated breast cancer(BC).Methods A total of 256 BC patients were retrospectively selected and divided into BRCA mutation group(116 cases)and BRCA wild group(140 cases)based on the BRCA results.Chi-square tests or independ-ent sample t-tests were used to compare the differences in clinicopathological characteristics and multiparametric MRI features between the BRCA mutation group and the wild group.Risk factors for BRCA-mutated BC were identified through univariate and multivariate logistic regression ananlyses,and a combined predictive model was constructed.Receiver operating characteristic(ROC)curve was used to ana-lyze the diagnostic efficacy of the model.Results There were statistically significant differences in T stage,human epidermal growth factor receptor 2(HER-2),Ki-67,non-mass enhancement,enhancement pattern,time-signal intensity curve(TIC)type,and apparent diffusion coefficient(ADC)values between the BRCA mutation group and the wild group.Univariate logistic regression analysis showed that T stage,HER-2,Ki-67,non-mass enhancement,enhancement pattern,TIC type,and ADC values were risk factors for BRCA-mutated BC(P<0.05).Multivariate logistic regression analysis revealed that T stage,HER-2,Ki-67,enhancement pattern,and TIC type were independent risk factors for BRCA-mutated BC(P<0.05).The combined model incorporating T stage,HER-2,Ki-67,enhancement pattern,and TIC type had the best diagnostic efficacy in predicting BRCA-mutated BC,with an area under the curve(AUC)of 0.751.Conclusion The combined model integrating T stage,HER-2,Ki-67,enhancement pattern,and TIC type has good efficacy in predicting BRCA-mutated BC.

OBJECTIVE To investigate the distribution,drug resistance and molecular characteristics of the Staph-ylococcus aureus strains isolated from intensive care unit(ICU)environment in some hospitals of Shanghai Pudong New Area so as to provide bases for prevention and control of infections.METHODS The specimens were collected from ICU environment of 8 medical institutions in Pudong District in 2019 and 2023,the S.aureus strains were i-solated and identified.The drug susceptibility testing was performed by microbroth dilution method.The drug re-sistance genes and virulence genes were predicted based on virulence factors of bacterial pathogens,the compre-hensive antibiotic resistance database(mcmaster.ca)and PubMLST,multilocus sequence typing(MLST)and phylogenetic analysis were performed.RESULTS Totally 3408 samples were collected,and the isolated S.aureus strains accounted for 1.29％(44/3408);the isolated strains form both the shared articles and the articles that health care workers directly contact accounted for 20.45％.The drug resistance rate to penicillin was highest(72.73％,32/44);the strains were completely susceptible to vancomycin,rifampicin,sulfamethoxazole-trime-thoprim,daptomycin and nitrofurantoin.The methicillin-resistant Staphylococcus aureus(MRSA)strains accoun-ted for 25.00％.The multi-drug resistance rate was 40.91％.The strains carried 26 types of drug resistance genes in total,covering 9 categories;the carrying rate of fluroquinolones resistance gene nor A was 100.00％.The strains carried 12 types of enterotoxin genes,the carrying rate of sea gene was highest(50.00％,22/44),some of the strains carried lukS-PV,lukF-PV and tsst gene.There were 14 types of sequence type(ST),dominated by ST7(13/44,29.55％),and novel ST type ST9342 was discovered.The phylogenetic analysis showed that all of the strains were divided into 2 major branches,and the strains with the same ST type were phylogenetically close on the evolutionary tree.CONCLUSIONS The S.aureus strains are prevalent in ICU environment and are highly re-sistant to antibiotics.The strains exhibit various ST types,which,to a certain degree,is associated with the path-ogenicity.

OBJECTIVE To investigate the distribution,drug resistance and molecular characteristics of the Staph-ylococcus aureus strains isolated from intensive care unit(ICU)environment in some hospitals of Shanghai Pudong New Area so as to provide bases for prevention and control of infections.METHODS The specimens were collected from ICU environment of 8 medical institutions in Pudong District in 2019 and 2023,the S.aureus strains were i-solated and identified.The drug susceptibility testing was performed by microbroth dilution method.The drug re-sistance genes and virulence genes were predicted based on virulence factors of bacterial pathogens,the compre-hensive antibiotic resistance database(mcmaster.ca)and PubMLST,multilocus sequence typing(MLST)and phylogenetic analysis were performed.RESULTS Totally 3408 samples were collected,and the isolated S.aureus strains accounted for 1.29％(44/3408);the isolated strains form both the shared articles and the articles that health care workers directly contact accounted for 20.45％.The drug resistance rate to penicillin was highest(72.73％,32/44);the strains were completely susceptible to vancomycin,rifampicin,sulfamethoxazole-trime-thoprim,daptomycin and nitrofurantoin.The methicillin-resistant Staphylococcus aureus(MRSA)strains accoun-ted for 25.00％.The multi-drug resistance rate was 40.91％.The strains carried 26 types of drug resistance genes in total,covering 9 categories;the carrying rate of fluroquinolones resistance gene nor A was 100.00％.The strains carried 12 types of enterotoxin genes,the carrying rate of sea gene was highest(50.00％,22/44),some of the strains carried lukS-PV,lukF-PV and tsst gene.There were 14 types of sequence type(ST),dominated by ST7(13/44,29.55％),and novel ST type ST9342 was discovered.The phylogenetic analysis showed that all of the strains were divided into 2 major branches,and the strains with the same ST type were phylogenetically close on the evolutionary tree.CONCLUSIONS The S.aureus strains are prevalent in ICU environment and are highly re-sistant to antibiotics.The strains exhibit various ST types,which,to a certain degree,is associated with the path-ogenicity.

Objective To explore the diagnostic value of a combined model based on clinicopathological and MRI features in BRCA-mutated ovarian cancer.Methods The data of 132 patients with ovarian cancer who underwent pathology and BRCA gene tes-ting were analyzed retrospectively,including 52 cases of BRCA mutation group and 80 cases of BRCA wild group.The differences of MRI features and clinicopathological features between BRCA mutation group and BRCA wild group were compared.Binary logistic regression was used to construct a joint prediction model and analyze its diagnostic efficiency.Results There were significant differ-ences in cytokeratin 7(CK7),estrogen receptor(ER),Ki-67 and lymphovascular invasion(LVI)between the BRAC mutation group and the BRAC wild group(P＜0.05).Univariate analysis showed that CK7,ER,Ki-67,LVI and the apparent diffusion coefficient(ADC)value of the cystic part of tumor were risk factors for BRCA-mutated ovarian cancer.The combined model based on CK7,ER,Ki-67,LVI,and the ADC value of the cystic part of tumor for the diagnosis of BRCA-mutated ovarian cancer had an area under the curve(AUC)of 0.765.Conclusion CK7,ER,Ki-67,LVI and the ADC value of the cystic part of tumor are risk factors for BRCA-mutated ovarian cancer.The combined model based on the above characteristics demonstrates good diagnostic efficacy for BRCA-mutated ovarian cancer.

Objective To investigate the diagnostic efficiency of patients with human epidermal growth factor receptor-2(HER-2)over expressed breast cancer via combining the dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)perfusion parameters,apparent diffusion coefficient(ADC)value and clinical feature model.Methods A total of 197 breast cancer patients who underwent DCE-MRI and diffusion weighted imaging(DWI)scans were analyzed retrospectively,including 47 breast cancer patients with HER-2 over expressed and 150 breast cancer patients with non-HER-2 over expressed.The t-test or chi-square test was used to compare the DCE-MRI perfusion parameters[Ktrans,Kep,Ve,W-in,W-out,and time to peak(TTP)],ADC value,and clinical feature between the two groups.The diagnostic efficiency of the models were analyzed via receiver operating characteristic(ROC)curves.Results There were significant difference in the maximum tumor diameter,minimum tumor diameter,T stage,N stage,Kep,W-in,and ADC value between HER-2 over expressed breast cancer and non-HER-2 over expressed breast cancer groups(P＜0.05).The proposed combined model,which included the combined maximum tumor diameter,minimum tumor diameter,T stage,N stage,Kep,W-in,and ADC value,showed a better diagnostic efficiency with area under the curve(AUC)(AUC=0.763)than the clinical model(AUC=0.634)based on the combined maximum tumor diameter,minimum tumor diameter,T stage,and N stage,and the imaging model(AUC=0.715)based on the combined Kep,W-in and ADC value.Conclusion The maximum tumor diameter,minimum tumor diameter,T stage,N stage,Kep,W-in,and ADC value may be associated with HER-2 over expressed breast cancer.Combining all above parameters can improve the diagnostic ability of breast cancer patients with HER-2 over expressed.

Objective To explore the mechanobiological mechanism of fluid shear force(FSF)on the protection,injury,and destruction of the structure and function of the blood-brain barrier(BBB)under normal physiological conditions,ischemic hypoperfusion,and postoperative hyperperfusion conditions.BBB is mainly composed of brain microvascular endothelial cells.Rat brain microvascular endothelial cells(rBMECs)were used as model cells to conduct the investigation.Methods rBMECs were seeded at a density of 1×105 cells/cm2 and incubated for 48 h.FSF was applied to the rBMECs at 0.5,2,and 20 dyn/cm2,respectively,simulating the stress BBB incurs under low perfusion,normal physiological conditions,and high FSF after bypass grafting when there is cerebral vascular stenosis.In addition,a rBMECs static culture group was set up as the control(no force was applied).Light microscope,scanning electron microscope(SEM),and laser confocal microscope(LSCM)were used to observe the changes in cell morphology and cytoskeleton.Transmission electron microscope(TEM)was used to observe the tight junctions.Immunofluorescence assay was performed to determine changes in the distribution of tight junction-associated proteins claudin-5,occludin,and ZO-1 and adherens junction-associated proteins VE-cadherin and PECAM-1.Western blot was performed to determine the expression levels of tight junction-associated proteins claudin-5,ZO-1,and JAM4,adherens junction-associated protein VE-cadherin,and key proteins in Rho GTPases signaling(Rac1,Cdc42,and RhoA)under FSF at different intensities.Results Microscopic observation showed that the cytoskeleton exhibited disorderly arrangement and irregular orientation under static culture and low shear force(0.5 dyn/cm2).Under normal physiological shear force(2 dyn/cm2),the cytoskeleton was rearranged in the orientation of the FSF and an effective tight junction structure was observed between cells.Under high shear force(20 dyn/cm2),the intercellular space was enlarged and no effective tight junction structure was observed.Immunofluorescence results showed that,under low shear force,the gap between the cells decreased,but there was also decreased distribution of tight junction-associated proteins and adherens junction-associated proteins at the intercellular junctions.Under normal physiological conditions,the cells were tightly connected and most of the tight junction-associated proteins were concentrated at the intercellular junctions.Under high shear force,the gap between the cells increased significantly and the tight junction and adherens junction structures were disrupted.According to the Western blot results,under low shear force,the expression levels of claudin-5,ZO-1,and VE-cadherin were significantly up-regulated compared with those of the control group(P<0.05).Under normal physiological shear force,claudin-5,ZO-1,JAM4,and VE-cadherin were highly expressed compared with those of the control group(P<0.05).Under high shear force,the expressions of claudin-5,ZO-1,JAM4,and VE-cadherin were significantly down-regulated compared with those of the normal physiological shear force group(P<0.05).Under normal physiological shear force,intercellular expressions of Rho GTPases proteins(Rac1,Cdc42,and RhoA)were up-regulated and were higher than those of the other experimental groups(P<0.05).The expressions of Rho GTPases under low and high shear forces were down-regulated compared with that of the normal physiological shear force group(P<0.05).Conclusion Under normal physiological conditions,FSF helps maintain the integrity of the BBB structure,while low or high shear force can damage or destroy the BBB structure.The regulation of BBB by FSF is closely related to the expression and distribution of tight junction-associated proteins and adherens junction-associated proteins.

Objective To observe the value of dual-source CT(DECT)virtual monoenergetic imaging(VMI)for differentiating prostate cancer(PC)and benign prostatic hyperplasia(BPH).Methods Thirty-three patients with PC(PC group)and 44 patients with BPH(BPH group)were retrospectively enrolled,and 40-100 keV(with 10 keV interval)VMI were reconstructed based on arterial phase DECT images,respectively.Clinical data,focal CT value and contrast-to-noise ratio(CNR)of VMI with different energy levels and conventional linear fusion images of arterial phase were compared between groups.Binary logistic regression models were constructed based on clinical data being significantly different between groups,focal CT value of VMI with energy level with the highest CNR,also focal CT value of conventional linear fusion images of arterial phase,respectively.The area under the receiver operating characteristic curve(AUC)was calculated to evaluate the efficacy of each model for differentiating PC and BPH.Results Free prostate-specific antigen(f-PSA),total prostate-specific antigen(t-PSA),focal CT value of 40-100 keV VMI and conventional linear fusion images of arterial phase in PC group were all higher,while short diameter in PC group was smaller than those in BPH group(all P＜0.05).Logistic regression models were constructed based on f-PSA,t-PSA,short diameter,CT value at 40 keV VMI and CT value at conventional linear fusion images of arterial phase,respectively,with AUC for differentiating PC and BPH of 0.879,0.902,0.701,0.911 and 0.857,respectively.Conclusion DECT VMI could be used as a supplementary examination for prostate diseases,and 40 keV VMI had the best efficacy for differentiating PC and BPH.