OBJECTIVE To establish the an optimal prediction model for carbapenem-resistant Acinetobacter bau-mannii(CRAB)infection in ICU patients based on machine learning(ML)so as to help clinicians to diagnose and make decisions.METHODS The clinical data were collected from the patients who were hospitalized in ICUs of a three-A hospital from Jan.1,2017 to Dec.31,2024 and were randomly divided into the training set and the test set in a 7∶3 ratio.The characteristic variables were selected by means of LASSO regression analysis in combina-tion with multivariate logistic regression analysis.Five types of M L classification models were integrated,the opti-mal model was analyzed and identified.The performance of the prediction model for CRAB infection in the ICU patients was evaluated with the use of sensitivity,specificity,accuracy,areas under receiver operating characteris-tic curves(AUCs),calibration curves,Hosmer-Lemeshow test and decision curve analysis(DCA).The outputs of the ML models were interpreted by Shapley additive explanations(SHAP)and permutation importance.RESULTS A total of 2 904 patients were enrolled in the study,695(23.93％)of whom had CRAB infection.The AUC of XGBoost model was highest in the training set and the test set,respectively(0.994 and 0.907).The result of Hosmer-Lemeshow test showed that the calibration curves of the XGBoost model indicated that the predicated risk was highly con-sistent with the observed risk(x2=7.323 and 4.609,P=0.513 and 0.764,respectively).The DCA curves showed that the XGBoost model performed best within the whole range of threshold,with the highest net profit.The length of ICU stay,use of tigecycline,central venous catheterization,use of carbapenems and use of ventilator were determined as the major predictive factors by means of SHAP.CONCLUSIONS The XGBoost model is established and interpreted by SHAP.It provides bases for screening of the ICU patients at high risk of CRAB infection.

Objective To analyze the antiviral effect of molnupiravir against influenza virus in vitro and in vivo.Methods The antiviral ability of molnupiravir against influenza virus strain H1N1 PR8 was detected in vitro and in vivo.H uman non-small cell lung cancer cell line(A549 cells)was used as an in vitro model of PR8 infection.The antiviral effects of molnupiravir on virus replication,protein synthesis,and viral particle formation were analyzed using real-time fluorescence quantitative polymerase chain reaction(qRT-PCR),Western blot(WB)assay,and plaque assay.PR8 nose-dripping infected C57BL/6 female mice were used as an in vivo infection model.The antivi-ral ability of molnupiravir was evaluated by detecting viral load,pathological changes,and immunohistochemistry in the control group,administration group,inoculation group,and inoculation-administration group.Results In vitro test results showed that molnupiravir had no significant inhibitory effect on influenza virus replication,protein syn-thesis,and virus particle formation(all P＞0.05).In vivo test results showed that compared with mice infected with H1N1 alone,the viral load in the lung tissue of mice treated with molnupiravir declined significantly,and the extent of pathological changes was milder.Immunohistochemical detection showed a significant weakening in nuclear protein(NP)antigen signal,and the expression levels of interferon(IFN)-α,interleukin(IL)-4,and IL-6 in the lungs were lower(all P＜0.01).Conclusion As a precursor with antiviral activity,molnupiravir can not exert anti-viral activity in lung-derived cells cultured in vitro,but can be transformed into an active form in the host,which significantly decreases the ability of H1N1 influenza virus to proliferate in the lungs and thereby alleviates the da-mage of virus to lung tissue.

OBJECTIVE To establish the an optimal prediction model for carbapenem-resistant Acinetobacter bau-mannii(CRAB)infection in ICU patients based on machine learning(ML)so as to help clinicians to diagnose and make decisions.METHODS The clinical data were collected from the patients who were hospitalized in ICUs of a three-A hospital from Jan.1,2017 to Dec.31,2024 and were randomly divided into the training set and the test set in a 7∶3 ratio.The characteristic variables were selected by means of LASSO regression analysis in combina-tion with multivariate logistic regression analysis.Five types of M L classification models were integrated,the opti-mal model was analyzed and identified.The performance of the prediction model for CRAB infection in the ICU patients was evaluated with the use of sensitivity,specificity,accuracy,areas under receiver operating characteris-tic curves(AUCs),calibration curves,Hosmer-Lemeshow test and decision curve analysis(DCA).The outputs of the ML models were interpreted by Shapley additive explanations(SHAP)and permutation importance.RESULTS A total of 2 904 patients were enrolled in the study,695(23.93％)of whom had CRAB infection.The AUC of XGBoost model was highest in the training set and the test set,respectively(0.994 and 0.907).The result of Hosmer-Lemeshow test showed that the calibration curves of the XGBoost model indicated that the predicated risk was highly con-sistent with the observed risk(x2=7.323 and 4.609,P=0.513 and 0.764,respectively).The DCA curves showed that the XGBoost model performed best within the whole range of threshold,with the highest net profit.The length of ICU stay,use of tigecycline,central venous catheterization,use of carbapenems and use of ventilator were determined as the major predictive factors by means of SHAP.CONCLUSIONS The XGBoost model is established and interpreted by SHAP.It provides bases for screening of the ICU patients at high risk of CRAB infection.

Objective To analyze the antiviral effect of molnupiravir against influenza virus in vitro and in vivo.Methods The antiviral ability of molnupiravir against influenza virus strain H1N1 PR8 was detected in vitro and in vivo.H uman non-small cell lung cancer cell line(A549 cells)was used as an in vitro model of PR8 infection.The antiviral effects of molnupiravir on virus replication,protein synthesis,and viral particle formation were analyzed using real-time fluorescence quantitative polymerase chain reaction(qRT-PCR),Western blot(WB)assay,and plaque assay.PR8 nose-dripping infected C57BL/6 female mice were used as an in vivo infection model.The antivi-ral ability of molnupiravir was evaluated by detecting viral load,pathological changes,and immunohistochemistry in the control group,administration group,inoculation group,and inoculation-administration group.Results In vitro test results showed that molnupiravir had no significant inhibitory effect on influenza virus replication,protein syn-thesis,and virus particle formation(all P＞0.05).In vivo test results showed that compared with mice infected with H1N1 alone,the viral load in the lung tissue of mice treated with molnupiravir declined significantly,and the extent of pathological changes was milder.Immunohistochemical detection showed a significant weakening in nuclear protein(NP)antigen signal,and the expression levels of interferon(IFN)-α,interleukin(IL)-4,and IL-6 in the lungs were lower(all P＜0.01).Conclusion As a precursor with antiviral activity,molnupiravir can not exert anti-viral activity in lung-derived cells cultured in vitro,but can be transformed into an active form in the host,which significantly decreases the ability of H1N1 influenza virus to proliferate in the lungs and thereby alleviates the da-mage of virus to lung tissue.

Natural killer (NK) cells are an important part of the body's innate immune system. As the first line of defense against pathogens, they need to be transformed into a mature state under the control of various cell signaling molecules and transcription factors to play cytotoxic and immune regulatory roles. Under the interaction of activated receptors and inhibitory receptors, NK cells are activated to perform a direct cell killing effect by secreting perforin and granzyme, or indirectly eliminate pathogenic microorganisms in the body by secreting various cytokines, such as type I and type II interferons. These functions of NK cells play a very important role in antiviral and anti-autoimmune diseases, especially in anti-tumor.
Humans ; Killer Cells, Natural ; Interferon-gamma ; Apoptosis ; Autoimmune Diseases ; Cytokines

Objective: To investigate the value of short tandem repeat (STR) genotyping in the diagnostic workup of molar and non-molar gestations with correlation of histological characteristics. Methods: Six hundred and fifty-six cases were selected based on clinically suspected hydropic abortion and/or molar pregnancy from July 2015 to September 2017 at Beijing Obstetrics and Gynecology Hospital. DNA was extracted from dissected chorionic villi and paired maternal endometrial FFPE tissue samples by Simplex OUP™ FFPE DNA Tissue Kit. STR genotyping was performed by PowerPlex 16 HS system. Results: DNA genotyping was informative in 649 of 656 cases, leading to identification of 215 hydatidiform mole gestations and 434 non-molar gestations. Most of non-molar gestations (375 cases, 86.4%) were diploid hydropic abortion. Various trisomy syndromes were found (53 cases, 12.2%), including trisomy 2, 3, 4, 7, 8, 13, 16 and 21. Only 2(0.5%) digynic triploid gestations were detected. Moreover, 4 cases (0.9%) of uniparental disomies (homologous or heterologous) were found. There were 196 cases with histologic diagnostic suspicious of hydatidiform moles were accurate sub-classified. Among them, 59 cases hydatidiform moles were under-diagnosed as diploid hydropic abortions, and 28 cases diploid hydropic abortions were over-diagnosed as hydatidiform moles.Compared with partial moles(PHM), there were no specific histomorphological features between the various types of non-molar gestations and partial moles for definitive diagnostic separation. There was no significant difference in the expression of p57^kip2 among PHM, trisomy and diploid hydropic abortions group (P=0.247). Conclusions STR genotyping can distinguish non-molar gestations from early hydatidiform moles, and efficiently avoid misdiagnosis based only on histological evaluation. Therefore, using STR genotyping, not only can the overdiagnosis of non-molar pregnancy be avoided, but also individualized management can be offered to patients including monitoring of serum hCG.

Objective To study the imaging manifestati ons and diagnostic evaluation of rounded atelectasis.Methods Imaging manifestation of round atelectasis in 4 c ases confirmed by pathology with complete clinical data,plain chest radiographs and CT were analysed.Results The lesions in 4 cases appeared as circular or el liptic masses with clear boundary,2.6～6.5 cm in diameter,located at subpleura o f lower lobule of lung,accompanied with pleural thickening.There was a acute angl e between the tumor and thickened pleura.The lucency of the lung adjacent to tum or incneased.The cordike structures consisted of blood vessels and bronchil ente red into tumors,which made the lateral boundary of tumor to hilum of lung obscur ed.“comet tail sign”and “air-brochogram sign”were seen in 3 cases.Conclusion The round atelectasis is of typical findings o n plain chest films and CT scans which play a very important role in diagnosis a nd differential diagnosis.