The chest wall is one of the most common sites of local recurrence after mastectomy. Radiation therapy has been proven to significantly reduce local recurrence and improve survival in breast cancer patients. In postmastectomy radiation therapy (PMRT), the dose build-up effects of high-energy radiation result in lower doses on the skin surface of the affected chest wall. To increase the skin dose, tissue compensators (boluses) need to be applied to the skin surface of the affected chest wall. This review primarily summarizes the indications, materials, thickness, and frequency of boluses used in PMRT, serving as a reference for clinical practice.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To investigate the effects and potential mechanisms of melatonin on cognitive dysfunction induced by long-term anesthesia with isoflurane.Methods:Male C57BL/6J mice aged 2 months were divided into control group, isoflurane group, melatonin group, and isoflurane+ melatonin group by random number table, with 6 mice in each group.Three days after anesthesia, cognitive function of mice was assessed by Y-maze and fear conditioning (FC) tests. ATP content in the hippocampus was measured by an ATP assay kit. Western blot was used to detect the expression of DRP1, pDRP1, MFN2, pAMPK and SIRT1 proteins in the hippocampus. Cultured HT-22 cells derived from mouse hippocampal neurons in vitro were divided into control group, isoflurane group, melatonin group, and isoflurane + melatonin group, and the levels of reactive oxygen species (ROS) in each group were detected by flow cytometry after intervention. Statistical analysis was performed by SPSS 22.0 software, and one-way ANOVA was used for comparisons among multiple groups.Results:(1) There was a statistically significant difference in the percentage of freezing behavior in contextual fear memory among the four groups of mice ( F=39.09, P<0.05). The percentage of freezing behavior in the isoflurane group was lower than that in the control group ((44.23±8.88)% vs (75.87±5.90)%, P<0.05), while the percentage of freezing behavior in the isoflurane+ melatonin group((67.45±14.89)%)was higher than that in the isoflurane group ( P<0.05). There was also a statistically significant difference in the percentage of exploration in the novel arm among the four groups of mice ( F=13.87, P<0.05). The percentage of exploration in the novel arm in the isoflurane group was lower than that in the control group((33.64±6.53)% vs (47.13±3.87)%, P<0.05), while the percentage of exploration in the novel arm in the isoflurane+ melatonin group((43.05±1.64)%)was higher than that in the isoflurane group ( P<0.05). (2) Statistically significant difference in the levels of ATP in the hippocampus was found among the four groups of mice ( F=49.22, P<0.05). The level of ATP in the hippocampus in the isoflurane group was lower than that in the control group((2.29±0.15)nmol/mg vs (3.58±0.12)nmol/mg, P<0.05), while the level of ATP in the hippocampus in the isoflurane+ melatonin group ((3.02±0.27)nmol/mg)was higher than that in the isoflurane group ( P<0.05). There was a statistically significant difference in the levels of ROS in HT-22 cells among the four groups ( F=18.36, P<0.05). The level of ROS in HT-22 cells in the isoflurane group was higher than that in the control group after anesthesia ( P<0.05), while the level of ROS in HT-22 cells in the isoflurane+ melatonin group was lower than that in the isoflurane group after anesthesia ( P<0.05). (3) There were statistically significant difference in the levels of pDRP1, pAMPK and SIRT1 protein in the hippocampus among the four groups of mice ( F=19.87, 21.20, 25.65, all P<0.05). The levels of pDRP1 and SIRT1 protein in the hippocampus in the isoflurane group were both lower than those in the control group (both P<0.05), while the levels of pDRP1 and SIRT1 protein in the hippocampus in the isoflurane+ melatonin group were both higher than those in the isoflurane group (both P<0.05). In the isoflurane group, the expression of pAMPK protein in the hippocampal region was higher than that in the control group ( P<0.05), while the expression of pAMPK protein in the isoflurane+ melatonin group was lower than that in the isoflurane group ( P<0.05). Conclusion:Melatonin improves long-term isoflurane anesthesia-induced cognitive dysfunction by regulating mitochondrial homeostasis through the AMPK/SIRT1 signaling pathway.

Objective:To investigate the effects and potential mechanisms of melatonin on cognitive dysfunction induced by long-term anesthesia with isoflurane.Methods:Male C57BL/6J mice aged 2 months were divided into control group, isoflurane group, melatonin group, and isoflurane+ melatonin group by random number table, with 6 mice in each group.Three days after anesthesia, cognitive function of mice was assessed by Y-maze and fear conditioning (FC) tests. ATP content in the hippocampus was measured by an ATP assay kit. Western blot was used to detect the expression of DRP1, pDRP1, MFN2, pAMPK and SIRT1 proteins in the hippocampus. Cultured HT-22 cells derived from mouse hippocampal neurons in vitro were divided into control group, isoflurane group, melatonin group, and isoflurane + melatonin group, and the levels of reactive oxygen species (ROS) in each group were detected by flow cytometry after intervention. Statistical analysis was performed by SPSS 22.0 software, and one-way ANOVA was used for comparisons among multiple groups.Results:(1) There was a statistically significant difference in the percentage of freezing behavior in contextual fear memory among the four groups of mice ( F=39.09, P<0.05). The percentage of freezing behavior in the isoflurane group was lower than that in the control group ((44.23±8.88)% vs (75.87±5.90)%, P<0.05), while the percentage of freezing behavior in the isoflurane+ melatonin group((67.45±14.89)%)was higher than that in the isoflurane group ( P<0.05). There was also a statistically significant difference in the percentage of exploration in the novel arm among the four groups of mice ( F=13.87, P<0.05). The percentage of exploration in the novel arm in the isoflurane group was lower than that in the control group((33.64±6.53)% vs (47.13±3.87)%, P<0.05), while the percentage of exploration in the novel arm in the isoflurane+ melatonin group((43.05±1.64)%)was higher than that in the isoflurane group ( P<0.05). (2) Statistically significant difference in the levels of ATP in the hippocampus was found among the four groups of mice ( F=49.22, P<0.05). The level of ATP in the hippocampus in the isoflurane group was lower than that in the control group((2.29±0.15)nmol/mg vs (3.58±0.12)nmol/mg, P<0.05), while the level of ATP in the hippocampus in the isoflurane+ melatonin group ((3.02±0.27)nmol/mg)was higher than that in the isoflurane group ( P<0.05). There was a statistically significant difference in the levels of ROS in HT-22 cells among the four groups ( F=18.36, P<0.05). The level of ROS in HT-22 cells in the isoflurane group was higher than that in the control group after anesthesia ( P<0.05), while the level of ROS in HT-22 cells in the isoflurane+ melatonin group was lower than that in the isoflurane group after anesthesia ( P<0.05). (3) There were statistically significant difference in the levels of pDRP1, pAMPK and SIRT1 protein in the hippocampus among the four groups of mice ( F=19.87, 21.20, 25.65, all P<0.05). The levels of pDRP1 and SIRT1 protein in the hippocampus in the isoflurane group were both lower than those in the control group (both P<0.05), while the levels of pDRP1 and SIRT1 protein in the hippocampus in the isoflurane+ melatonin group were both higher than those in the isoflurane group (both P<0.05). In the isoflurane group, the expression of pAMPK protein in the hippocampal region was higher than that in the control group ( P<0.05), while the expression of pAMPK protein in the isoflurane+ melatonin group was lower than that in the isoflurane group ( P<0.05). Conclusion:Melatonin improves long-term isoflurane anesthesia-induced cognitive dysfunction by regulating mitochondrial homeostasis through the AMPK/SIRT1 signaling pathway.

The chest wall is one of the most common sites of local recurrence after mastectomy. Radiation therapy has been proven to significantly reduce local recurrence and improve survival in breast cancer patients. In postmastectomy radiation therapy (PMRT), the dose build-up effects of high-energy radiation result in lower doses on the skin surface of the affected chest wall. To increase the skin dose, tissue compensators (boluses) need to be applied to the skin surface of the affected chest wall. This review primarily summarizes the indications, materials, thickness, and frequency of boluses used in PMRT, serving as a reference for clinical practice.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Purpose/Significance Gestational hypertension poses a serious threat to maternal health.Artificial intelligence(AI)fol-low-up and management systems contributes to the health of gestational hypertension.Method/Process The paper establishes an AI fol-low-up system for gestational hypertension based on big data technology and data platforms,including modules such as patient informa-tion management,follow-up data management,follow-up plan management,and patient course management.Result/Conclusion The follow-up system can assist doctors in understanding changes in patients'diseases and meet the hospital's follow-up management re-quirements for gestational hypertension in outpatient clinics.

Objective To observe the value of artificial neural network(ANN)model based on recursive feature elimination-support vector machine(RFE-SVM)for differentiating ductal carcinoma in situ(DCIS)and DCIS complicated with microinvasion(DCISM).Methods Totally 296 female patients with single breast cancer(244 cases of DCIS and 52 cases of DCISM)were retrospectively collected as training set.Then 120 female patients with single breast cancer(87 cases of DCIS and 33 cases of DCISM)were prospectively enrolled as validation set.The general data,mammography and MRI findings were compared between sets.The optimal feature subsets for establishing ANN model were screened.Receiver operating characteristic curve was drawn,and the area under the curve(AUC)was calculated to evaluate the efficacy of ANN model for differentiating DCIS and DCISM.Results Ki-67 index,the minimum apparent diffusion coefficient(ADCmin),nuclear grade,ADCheterogeneity,maximum diameter of lesion,patient's age,P63,lesion enhancement type,calcification status and necrosis were the selected top 10 optimal feature subsets.The accuracy,sensitivity,specificity,positive predictive,negative predictive and AUC of ANN model for differentiating DCIS and DCISM was 91.55％,63.46％,97.54％,84.62％,92.61％and 0.950 in training set,respectively,while was 80.00％,69.70％,83.91％,62.16％,87.95％and 0.896 in validation set,respectively.The calibration curves of ANN model were consistent with the ideal curves in both training and validation set(P=0.355,0.480),which also expressed high clinical net benefit.Conclusion ANN model based on SVM-RFE could be used to differentiate DCIS and DCISM effectively.