Objective To compare the application effects of plankton multiplex polymerase chain reac-tion-capillary electrophoresis(PCR-CE),SYBR Green Ⅰ real-time quantitative PCR(qPCR)and microwave digestion-vacuum filtration-automated scanning electron microscopy(MD-VF-Auto SEM)in the diagnosis of drowning.Methods Lung,liver and kidney tissues from 212 drowned corpses and 30 non-drowned corpses were examined respectively by the three drowning-related plankton testing methods,and the detection rates of plankton in each tissue by three methods were compared.Results In drowned corpses,the total detection rates of PCR-CE,qPCR,and MD-VF-Auto SEM were 93.9%,96.2%,and 95.3%,respectively,with no statistically significant difference(P>0.05).The detection rate of lung tissue by MD-VF-Auto SEM(100%)was higher than those of PCR-CE and qPCR(P<0.05),and there was no significant difference in the detection rates of the three methods in liver or kidney tissues(P>0.05).In non-drowning corpses,a small number of diatoms(less than 10 cells/10 g)were detected by MD-VF-Auto SEM method,only in liver and kidney tissues,while the other two methods yielded negative results for all tissues.Conclusion All three methods have good efficacy in the examination of drowned corpses.The MD-VF-Auto SEM method directly observes diatom morpho-logical characteristics through scanning electron microscopy,and the qualitative and quantitative analy-ses are intuitive and accurate.It has great advantages in the examination of difficult degradation samples.The PCR-CE method and qPCR method have a low sample demand(0.5 g),are easy to operate and have short detection time(4-7 h).They are easy to be applied in the grassroots depart-ments and are suitable for the rapid determination of drowned corpses in routin cases.The combina-tion of the two DNA methods with the MD-VF-Auto SEM method can increase the detection rate of plankton,ensuring the reliability of examination results.This combined use is of significant importance in the application of drowning diagnosis.

Objective To investigate the effect of monitor unit(MU)optimization on volumetric modulated arc therapy(VMAT)for nasopharyngeal carcinoma(NPC).Methods Totally 21 NPC patients confirmed pathologically at some hospital from October 2022 to March 2023 were selected retrospectively,and for each patient a double-arc VMAT plan named base was designed without using the monitor unit objective(MUO)tool and optimized by the photon optimization algorithm.With the parameter kept constant,Plan base was reoptimized with only the MUO tool by regulating its Maximum MU to 30％of the total MU of Plan base and setting Strength values as 50,80 and 100 respectively to obtain Plan S50,S80 and S100.Plan base was compared with Plan S50,S80 and S100 in terms of dose distributions of the target volumes and organs at risk(OARs),MU,beam-on time and γ pass rate.SPSS 17.0 software was used for statistical analysis.Results In Plan S100 only 4 patients had a decrease of more than 4％in theD98％to the PCTV2 target volume compared with that in Plan base.In Plan S80 only 2 patients had a decrease of between 3％and 4％in the Dmax to PGTV and PGTVnd and D98％to PCTV2 when compared with those in Plan base,and most of the dosimetric parameters to the other target volumes had the changing amplitudes lower than 2％.When compared with Plan base,Plan S50,S80 and S100 all increased theDmaxto the brainstem significantly(all P＜0.05),with the maximum increment not exceeding 1.5％.In Plan S50 the D502％and Dmean to the right and left parotid glands were lowered,and in Plan S80 there were decreases found in the Dmean to the right and left parotid glands andD50％to the left parotid gland,with statistically significant differences(P＜0.001),and in Plan S100 the D50％and Dmean to the right and left parotid glands and the Dmax to the spinal cord increased significantly when compared with those in Plan base(all P＜0.05).In Plan S80 and S100 the V40 of the thyroid relatively rose statistically when compared with that in Plan base(P＜0.05).In Plan S50,S80 and S100 the MU was decreased by 5.1％,21.5％and 30.9％respectively when compared with that in Plan base,and the average beam-on time of all the four plans was kept within 2.5 min.γ pass rates increased sequentially for Plan base,S50,S80 and S100 under 1％/1 mm conditions.Conclusion In NPC VMAT MU optimization effectively decreases the planned MU and improves γ pass rates under 1％/1 mm conditions while ensuring the dose to the target volume and OAR protection.[Chinese Medical Equipment Journal,2025,46(2):56-62]

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Objective:To explore the construction of an evaluation model for aortic root anatomy and calcium burden in patients with bicuspid aortic valve (BAV) stenosis before transcatheter aortic valve replacement (TAVR) based on deep learning (DL) algorithms.Methods:A retrospective collection of 362 BAV stenosis patients who underwent TAVR from September 2023 to May 2024 was performed. All patients underwent cardiac CT angiography. The patients were divided into training group ( n=104), internal validation group ( n=206), and external validation group ( n=52). A DL model was trained on the training dataset to assess aortic root anatomy and calcification burden. The evaluation included the segmentation accuracy of the algorithm, the measurement performance of key anatomical structures (i.e., valve leaflets and type-1 and type-2 fusion raphe), and calcification burden, as well as the measurement efficiency. Overall segmentation performance was assessed using the average Dice coefficient (ADC). The fine-scale segmentation quality was validated by the 95th-percentile Hausdorff distance (HD-95) and the average symmetric surface distance (ASSD). The consistency of the measurement results was assessed using the Pearson correlation coefficient and the intraclass correlation coefficient ( ICC) with a two-way mixed model for absolute agreement. In addition, the total time and total mouse movement distance required for manual assessment versus the DL model on the validation datasets were recorded and compared. Results:The algorithm demonstrated excellent segmentation performance on aortic root anatomical targets, achieving outstanding consistency within both internal and external validation datasets (0.955

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Objective To investigate the effect of monitor unit(MU)optimization on volumetric modulated arc therapy(VMAT)for nasopharyngeal carcinoma(NPC).Methods Totally 21 NPC patients confirmed pathologically at some hospital from October 2022 to March 2023 were selected retrospectively,and for each patient a double-arc VMAT plan named base was designed without using the monitor unit objective(MUO)tool and optimized by the photon optimization algorithm.With the parameter kept constant,Plan base was reoptimized with only the MUO tool by regulating its Maximum MU to 30％of the total MU of Plan base and setting Strength values as 50,80 and 100 respectively to obtain Plan S50,S80 and S100.Plan base was compared with Plan S50,S80 and S100 in terms of dose distributions of the target volumes and organs at risk(OARs),MU,beam-on time and γ pass rate.SPSS 17.0 software was used for statistical analysis.Results In Plan S100 only 4 patients had a decrease of more than 4％in theD98％to the PCTV2 target volume compared with that in Plan base.In Plan S80 only 2 patients had a decrease of between 3％and 4％in the Dmax to PGTV and PGTVnd and D98％to PCTV2 when compared with those in Plan base,and most of the dosimetric parameters to the other target volumes had the changing amplitudes lower than 2％.When compared with Plan base,Plan S50,S80 and S100 all increased theDmaxto the brainstem significantly(all P＜0.05),with the maximum increment not exceeding 1.5％.In Plan S50 the D502％and Dmean to the right and left parotid glands were lowered,and in Plan S80 there were decreases found in the Dmean to the right and left parotid glands andD50％to the left parotid gland,with statistically significant differences(P＜0.001),and in Plan S100 the D50％and Dmean to the right and left parotid glands and the Dmax to the spinal cord increased significantly when compared with those in Plan base(all P＜0.05).In Plan S80 and S100 the V40 of the thyroid relatively rose statistically when compared with that in Plan base(P＜0.05).In Plan S50,S80 and S100 the MU was decreased by 5.1％,21.5％and 30.9％respectively when compared with that in Plan base,and the average beam-on time of all the four plans was kept within 2.5 min.γ pass rates increased sequentially for Plan base,S50,S80 and S100 under 1％/1 mm conditions.Conclusion In NPC VMAT MU optimization effectively decreases the planned MU and improves γ pass rates under 1％/1 mm conditions while ensuring the dose to the target volume and OAR protection.[Chinese Medical Equipment Journal,2025,46(2):56-62]

Creutzfeldt-Jakob disease(CJD)is a rapidly progressive and fatal neurodegenerative disorder caused by prions,with certain infectivity and iatrogenic transmission risks.With the rapid progress and application of new dia-gnostic biomarkers and detection methods,as well as the construction and improvement of surveillance and reporting systems,the detection of CJD in patients domestically and internationally has shown an increasing trend year by year.Due to its long incubation period and heterogeneity of early symptoms,early identification and diagnosis of the disease is difficult,increasing the risk of transmission within medical institutions.Currently,there is a lack of con-sensus on the infection prevention and control of CJD.In order to timely identify and diagnose CJD as well as effec-tively block its transmission in medical institutions,this consensus summarizes 15 clinical concerns and formulates 24 specific recommendations based on the latest domestic and international research findings and clinical evidence,as well as combines with clinical practice,aiming to standardize healthcare-associated infection prevention and control measures for CJD and reduce its transmission risk in medical institutions.

Objective:To explore the construction of an evaluation model for aortic root anatomy and calcium burden in patients with bicuspid aortic valve (BAV) stenosis before transcatheter aortic valve replacement (TAVR) based on deep learning (DL) algorithms.Methods:A retrospective collection of 362 BAV stenosis patients who underwent TAVR from September 2023 to May 2024 was performed. All patients underwent cardiac CT angiography. The patients were divided into training group ( n=104), internal validation group ( n=206), and external validation group ( n=52). A DL model was trained on the training dataset to assess aortic root anatomy and calcification burden. The evaluation included the segmentation accuracy of the algorithm, the measurement performance of key anatomical structures (i.e., valve leaflets and type-1 and type-2 fusion raphe), and calcification burden, as well as the measurement efficiency. Overall segmentation performance was assessed using the average Dice coefficient (ADC). The fine-scale segmentation quality was validated by the 95th-percentile Hausdorff distance (HD-95) and the average symmetric surface distance (ASSD). The consistency of the measurement results was assessed using the Pearson correlation coefficient and the intraclass correlation coefficient ( ICC) with a two-way mixed model for absolute agreement. In addition, the total time and total mouse movement distance required for manual assessment versus the DL model on the validation datasets were recorded and compared. Results:The algorithm demonstrated excellent segmentation performance on aortic root anatomical targets, achieving outstanding consistency within both internal and external validation datasets (0.955

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.