Brucellosis,a worldwide epidemic bacterial zoonotic infectious disease caused by bacteria of the genus Brucella,jeopardizes livestock production and poses a major threat to public health safety.Among the various components of Brucella,the outer membrane proteins play crucial roles as the primary immune and protective antigens.These proteins are closely asso-ciated with Brucella's virulence,regulation of the immune response,and ability to survive and multiply within host cells.This article summarizes recent research progress in the primary outer membrane proteins of Brucella,and offers a synthesized view of the current knowledge landscape.Understanding the antigenic characteristics of Brucella outer membrane proteins may sub-stantially contribute to the establishment of new diagnostic methods and the design of new vaccines,thus potentially leading to more effective prevention strategies against brucellosis.The review provides a reference for future studies and may aid in brucel-losis control efforts.

Objective:To investigate the molecular mechanism of proteolytic cleavage of unusually large von Willebrand Factor(ULVWF)on endothelial cells by ADAMTS13(a disintegrin and metalloprotease with thrombospondin type 1 repeats-13)in the absence of fluid shear stress,so as to provide a theoretical basis for the pathogenesis of thrombotic thrombocytopenic purpura(TTP)and other thrombotic disorders.Methods:The ADAMTS13-mediated proteolysis of ULVWF on the surface of endothelial cells in the absence of fluid shear stress was observed through immunofluorescence microscopy.The variation in VWF antigen levels in the conditioned media were determined by ELISA assay.The levels of VWF and the proteolytic fragments released into the conditioned media were determined by ELISA assay and Western blot in the absence and presence of fluid shear stress or FⅧ.The effect of ADAMTS13-mediated ULVWF cleavage on the normal distribution of plasma VWF multimers was evaluated by multimer analysis.Histamine stimulated human umbilical vein endothelial cells(HUVECs)were incubated with ADAMTS13 and various N-and C-terminally truncated mutants.Then the ULVWF that maintained binding to the cells were observed through immunofluorescence microscopy and the soluble ULVWF released from endothelial cells was determined by ELISA,so as to demonstrate the domains of ADAMTS13 required for proteolysis of ULVWF on endothelial cells.Results:The ULVWF strings on the endothelial cell surface were rapidly proteolyzed by recombinant and plasma ADAMTS13 in the absence of fluid shear stress.This proteolytic processing of ULVWF depended on incubation time and AD AMTS 13 concentration,but not shear stress and FⅧ.The distribution of VWF releaseded by ADAMTS13-mediated proteolysis was quite similar to that secreted by endothelial cells under histamine stimulation,suggesting the ULVWF cleavage occured at the cell surface.The proteolysis of the ULVWF on endothelial cells required the Cys-rich(CysR)and spacer domains,but not the TSP1 2-8 and CUB domains of ADAMTS13.Conclusion:The ULVWF polymers on endothelial cells are sensitive to ADAMTS13-mediated cleavage even in the absence of fluid shear stress.The findings provide novel insight into the molecular mechanism of ADAMTS13-mediated ULVWF cleavage at the cellular level and may contribute to understanding of the pathogenesis of TTP and other thrombotic disorders.

Objective:To explore the clinical manifestations,pathological features,immunophenotype,as well as diagnosis,treatment and prognosis of patients with CD4-CD56+blastic plasmacytoid dendritic cell neoplasm(BPDCN),in order to further understand the rare disease.Methods:The clinical data,laboratory examinations and treatment regimens of two patients with CD4-CD56+BPDCN in the First Affiliated Hospital of Wannan Medical College were retrospectively analyzed.Results:The two patients were both elderly males with tumor involved in skin,bone marrow,lymph nodes,etc.Immunohistochemical results of skin lesions showed that both CD56 and CD123 were positive,while CD4,CD34,TdT,CD3,CD20,MPO and EBER were negative.Flow cytometry of bone marrow demonstrated that CD56,CD123,and CD304 were all positive,while specific immune markers of myeloid and lymphoid were negative.Two patients were initially very sensitive to acute lymphoblastic leukemia or lymphomatoid chemotherapy regimens,but prone to rapid relapse.The overall survival of both patients was 36 months and 4 months,respectively.Conclusion:CD4-CD56+BPDCN is very rare and easily misdiagnosed as other hematological tumors with poor prognosis.Acute lymphoblastic leukemia or lymphomatoid therapy should be used first to improve the poor prognosis.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Objective To propose a sperm classification model based on convolutional neural network to enhance the accuracy of sperm morphological classification.Methods A FT-EfficientNet model was constructed using EfficientNetB0 as the base model,which was fine-tuned by data preprocessing enhancement,transfer learning and cosine decay.Classification experi-ments were performed on the sperm public datasets SCIAN-Morpho and HuSHeM,and the datasets were segmented and vali-dated using 5-fold cross-validation.The classification results by the FT-EfficientNet model were compared with those by the cascade ensemble of support vector machines(CE-SVM)model,the adaptive patch-based dictionary learning(APDL)model,fine tuning of visual geometry group(FT-VGG)model,morphological classification of human sperm heads(MH-HSH)model and transfer learning(TL)model.Ablation experiments were performed in the SCIAN-Morpho dataset to verify the effect of different fine-tuning methods on the model.Results The FT-EfficientNet model proposed had the accuracy,precision and F1 score on the SCIAN-Morpho validation set being 64.1％,63.8％and 64.8％,respectively,which were better than CE-SVM,APDL,FT-VGG and MC-HSH models.The recall rate of the model proposed(65.2％)was slightly lower than that of MC-HSH model(68.0％).The accuracy,precision,F1 score and recall rate on the HuSHeM validation set was 95.4％,95.8％,95.4％and 96.0％,respectively,which were slightly lower than those of TL model while better than those of CE-SVM,APDL,FT-VGG and MC-HSH models.Ablation experiments showed the FT-EfficientNet model behaved the best in fine-tuning.Conclusion The sperm classification model based on convolutional neural network facilitates sperm morphology classification with high accuracy and performance.[Chinese Medical Equipment Journal,2024,45(10):7-13]

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10^-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

Objective To investigate the appropriate venous access for obese patients undergoing metabolic and bariatric surgery by comparing the clinical outcomes of different lengths of peripheral intravenous catheters.Methods Inpatients who underwent bariatric surgery in a tertiary hospital in Zhejiang from August 2022 to December 2022 were selected as the study population using a fixed-point continuous convenience sampling method.A stratified block randomisation method was used to divide the group into an experimental group 1(mini-midline catheters),an experimental group 2(midline catheters)and a control group(short peripheral intravenous catheters,Short PIVCs).The incidence of catheter-related complications,the rate of extubation due to complications,the duration of catheter retention,the time to first catheter-related complication were compared in the 3 groups.Results A total of 186 patients were included,with 62 patients in each group.The overall incidence of catheter-related complications in experimental group 1,experimental group 2,and control group were 25.81％,8.06％,and 58.06％.The extubation rates due to complications were 19.35％,4.84％,and 41.94％,and the duration of catheter retention was 7.00(6.00,7.00)d,7.00(6.00,7.00)d,6.00(3.00,6.25)d.The differences were statistically different(P＜0.05)when comparing the 3 groups.Among them,the differences in the overall incidence of catheter-related complications and the rate of extubation due to complications were statistically significant when comparing experimental group 1 with the control group,experimental group 2 with the control group,and experimental group 1 with experimental group 2(P＜0.017);the duration of catheter retention in both experimental group 1 and experimental group 2 were higher than it in the control group,and the differences were statistically different(P＜0.017).Conclusion The complication rate of mini-midline catheters and midline catheters is lower than that of short ones,and the indwelling time is consistent with the perioperative period of metabolic and bariatric surgery,which is suitable for use in patients undergoing metabolic and bariatric surgery.

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of liquiritin apioside,alibiflorin,swertiamarin,methyl gallate,benzoylpaeoniflorin,sweroside,6′-O-β-D-glucosylgentiopicroside,isoliquiritigenin,loganic acid,liquiritigenin,gallic acid,paeoniflorin,oxypaeoniflorin,gentiopicroside,glycyrrhizic acid,isoliquiritoside and liquiritin in Yangxue Ruanjian Capsules.METHODS The analysis was performed on a 40℃thermostatic Waters BEH C18column(2.1 mm×100 mm,1.7 μm),with the mobile phase comprising of 2 mmol/L ammonium acetate(containing 0.1%formic acid)-acetonitrile flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in negative ion scanning with multiple reaction monitoring mode.RESULTS Seventeen constituents showed good linear relationships within their own ranges(r>0.999 6),whose average recoveries were 91.33%-104.03%with the RSDs of 1.58%-3.50%.CONCLUSION This rapid,accurate and stable method can be used for the quality control of Yangxue Ruanjian Capsules.

Objective To elucidate the effect of curcumol on hepatic stellate cell iron death and epithelial-mesenchymal transition(EMT),and to investigate the molecular mechanism of its anti-liver fibrosis effect.Methods A model of hepatic stellate cell activation was constructed using normal cultured hepatic stellate cells in vitro,and the cells were divided into blank group and experimental-L,-M,-H groups.The blank group was given DMEM complete culture solution for normal culture;the experimental-L,-M,-H groups were given DMEM complete culture solution containing 12.5,25.0 and 50.0 mg·L-1 curcumol for 48 h of intervention.The effects of curcumol on the proliferation of hepatic stellate cells was observed by CCK-8.The expression levels of glutathione peroxidase 4(GPX4)and solute carrier family 7 member 11(SLC7A11)were detected by Western blot.The expression levels of E-cadherin and N-cadherin were detected by immunofluorescence.Results The cell proliferation rates of the experimental-M,-H groups and blank group were(68.97±5.61)％,(61.91±4.40)％and(118.07±10.01)％;the relative expression levels of GPX4 were 0.37±0.04,0.28±0.03 and 0.58±0.05;the relative expression levels of SLC7A11 were 0.38±0.04,0.28±0.03 and 0.60±0.05;E-cadherin levels were 6.76±1.09,9.57±1.73 and 2.05±0.72;N-cadherin levels were 5.66±0.66,3.44±0.78 and 10.37±0.66.The differences of above indicators were statistically significant between the blank group and the experimental-M,-H groups(P＜0.05,P＜0.01).Conclusion Curcumol promotes iron death in hepatic stellate cells,thereby inhibiting hepatic stellate cell EMT,which may be its molecular mechanism to prevent and treat liver fibrosis.