Objective: To investigate the distribution characteristics of previous infection of human parvovirus B19(HPV B19) among blood donors in Xi 'an, and to provide data support and theoretical basis for formulating individualized and precise blood screening strategies. Methods: A total of 970 qualified blood samples tested at Shaanxi Blood Center from August to September 2024 were randomly selected. The levels of HPV B19 IgG antibodies in the serum were detected by enzyme-linked immunosorbent assay (ELISA). The distribution characteristics of the samples were analyzed from the perspectives of age, gender, education level, occupation, blood type and region. Results: The positive rate of HPV B19 IgG antibodies among blood donors in Xi 'an was 25.26%(245/970), which increased gradually with age (P<0.05). There was no significant difference in the positive rate of HPV B19 IgG antibodies among blood donors of different genders, education levels, occupations, or blood types (P>0.05). Univariate logistic regression analysis showed that past HPV B19 infection was only related to age (P<0.05). The distribution of positive blood samples in 13 districts and counties of Xi 'an was counted based on the blood collection sites. The results showed that there was no significant global spatial autocorrelation in the distribution of positive samples. Among them, the Weiyang District and Beilin District exhibited a "high-high" cluster (P<0.05), while Chang'an District exhibited a "low-high" cluster (P<0.01). Conclusion: A certain proportion of blood donors in Xi'an showed past infection with HPV B19, which was only correlated with age and demonstrated an upward trend. It is recommended to continue expanding the screening scope and incorporate screening for this virus in blood transfusion processes involving susceptible populations.

Objective Based on the endoplasmic reticulum stress(ERS)inositol-requiring enzyme-1α(IRE1α)/apoptosis signal-regulated kinase 1(ASK1)/c-Jun N-terminal kinase(JNK)pathway to investigate the intervention effect of Ziziphi Spinosae Semen(ZSS)-Albiziae Flos(AF)on the depression model of rats,which were prepared by solitary rearing combined with chronic unpredictable mild stress(CUMS).Methods A total of 144 rats were randomly divided into normal group,model group,high-,medium-and low-dose groups of ZSS-AF,and Venlafaxine group.In addition to the normal group,the rats in other groups were isolated for 21 days combined with CUMS to prepare the depression model.The behavioral changes of rats were observed by open field test and Morris water maze test.The ultrastructural changes of hippocampal neurons were observed by transmission electron microscope.TUNEL staining was used to observe the apoptosis of nerve cells in hippocampus.The protein expression levels of IRE1α,phosphorylated(P)-IRE1α,ASK1,P-ASK1,JNK,P-JNK,B cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax)and cysteme aspartate specific protease-3(Caspase-3)in hippocampus were detected by Western Blot.The mRNA expression levels of IRE1α,ASK1,JNK,Bax,Bcl-2 and Caspase-3 in hippocampus were detected by Real-Time PCR.Results Compared with the normal group,the scores of horizontal movement and vertical movement in the open field test of rats in the model group were decreased(P＜0.01).In the water maze test,the escape latency was increased and the number of crossing the original platform was decreased(P＜0.01).The number of hippocampal apoptosis was increased(P＜0.01).The protein expression levels of P-IRE1 α/IRE1 α,P-ASK1/ASK1,P-JNK/JNK,Bax,Caspase-3 and mRNA expressions of IRE1α,ASK1,JNK,Bax,Caspase-3 in hippocampus were increased,while the protein and mRNA expression levels of Bcl-2 were decreased(P＜0.01).Compared with model group,the scores of horizontal movement and vertical movement in the open field test of rats in each dose ZSS-AF groups and Venlafaxine group were increased(P＜0.01).In the water maze test,the escape latency was decreased and the times of crossing the original platform was increased(P＜0.01).The number of hippocampal apoptosis was decreased(P＜0.01).The mRNA expression levels of P-IRE1α/IRE1α,P-ASK1/ASK1,P-JNK/JNK,Bax,Caspase-3 protein and IRE1α,ASK1,JNK,Bax,Caspase-3 in hippocampus were decreased,while the protein and mRNA expression levels of Bcl-2 were increased(P＜0.05,P＜0.01).The effect of medium-dose ZSS-AF group was better than that of high-and low-dose groups.Conclusion ZSS-AF may play an antidepressant role by regulating IRE1α/ASK1/JNK pathway of endoplasmic reticulum stress.

Objective:To construct a prediction model for the clinical supply of blood components in Xi′an City from 2023 to 2025.Methods:Based on the blood supply data of the Blood Management Information System of Shaanxi Provincial Blood Center from January 2013 to December 2022, a gray prediction model and an exponential curve fitting model were used to construct the prediction model, and the optimal prediction model was determined according to the error parameters of the relevant indicators of the model. The supply of blood components in Xi′an from 2023 to 2025 was predicted.Results:The fitting equations of the exponential curve fitting model to predict the supply of suspended red blood cells, platelets and cryoprecipitate in Xi′an were, x（1）（ t+1）=1.16e 0.04t， x（1）（ t+1）=1.04e 0.12t and x（1）（ t+1）=1.01e 1.10t, respectively. The mean absolute errors (mean relative errors) of the exponential curve fitting model in predicting the supply of suspended red blood cells, platelets and cryoprecipitate in Xi′an were 10 488.7 (0.05%), 2 114.9 (0.08%) and 3 089.6 (0.07%), respectively, which were lower than those of the gray prediction model, about 10 488.7 (3.44%), 2 152.78 (8.20%) and 3 441.35 (7.92%), respectively. The exponential curve fitting model predicted that the clinical supply of blood components in Xi′an would increase year by year from 2023 to 2025, and the clinical supply of suspended red blood cells, platelets, and cryoprecipitate in Xi′an would increase to 409 467 U, 69 818 therapeutic volume and 94 724 U, respectively by 2025. Conclusion:The exponential curve fitting model can make a good prediction of the clinical supply of blood components in Xi′an City.

Objective:To construct a prediction model for the clinical supply of blood components in Xi′an City from 2023 to 2025.Methods:Based on the blood supply data of the Blood Management Information System of Shaanxi Provincial Blood Center from January 2013 to December 2022, a gray prediction model and an exponential curve fitting model were used to construct the prediction model, and the optimal prediction model was determined according to the error parameters of the relevant indicators of the model. The supply of blood components in Xi′an from 2023 to 2025 was predicted.Results:The fitting equations of the exponential curve fitting model to predict the supply of suspended red blood cells, platelets and cryoprecipitate in Xi′an were, x（1）（ t+1）=1.16e 0.04t， x（1）（ t+1）=1.04e 0.12t and x（1）（ t+1）=1.01e 1.10t, respectively. The mean absolute errors (mean relative errors) of the exponential curve fitting model in predicting the supply of suspended red blood cells, platelets and cryoprecipitate in Xi′an were 10 488.7 (0.05%), 2 114.9 (0.08%) and 3 089.6 (0.07%), respectively, which were lower than those of the gray prediction model, about 10 488.7 (3.44%), 2 152.78 (8.20%) and 3 441.35 (7.92%), respectively. The exponential curve fitting model predicted that the clinical supply of blood components in Xi′an would increase year by year from 2023 to 2025, and the clinical supply of suspended red blood cells, platelets, and cryoprecipitate in Xi′an would increase to 409 467 U, 69 818 therapeutic volume and 94 724 U, respectively by 2025. Conclusion:The exponential curve fitting model can make a good prediction of the clinical supply of blood components in Xi′an City.

Objective To explore the clinical effect of a trapezoidal transparent corneal incision during phacoemulsi-fication.Methods A total of 57 patients(68 eyes)undergoing phacoemulsification were selected and divided into a con-ventional incision group and a trapezoidal incision group using a random number table method.There were 28 patients(34 eyes)in the conventional incision group,including 15 eyes(males)and 19 eyes(females),with an age range of 41-82(65.0±10.1)years;and there were 29 patients(34 eyes)in the trapezoidal incision group,including 21 eyes(males)and 13 eyes(females),with an age range of 46-87(66.0±11.1)years.All patients underwent cataract phacoemulsification combined with intraocular lens(IOL)implantation.A 3.0 mm transparent corneal incision was made for patients in the conventional incision group,while an improved trapezoidal transparent corneal incision was made for patients in the trape-zoidal incision group.The uncorrected visual acuity,intraocular pressure,corneal astigmatism,and incidence of intraoper-ative and postoperative complications were compared between the two groups.Results The uncorrected visual acuity of patients in the trapezoidal incision group was better than that of patients in the conventional incision group at 1 week and 3 months after surgery,and the differences were statistically significant(both P＜0.05).There was no statistically significant difference in intraocular pressure and corneal astigmatism between the two groups of patients at 1 week,1 month,and 3 months after surgery(all P＞0.05).The number of eyes with anterior chamber collapse and the number of eyes requiring a watertight incision in the conventional incision group were greater than those in the trapezoidal incision group during sur-gery,and the differences were statistically significant(both P＜0.05).The number of eyes with incision edema and the number of eyes with incision gap in the conventional incision group were greater than those in the trapezoidal incision group after surgery,and the differences were statistically significant(both P＜0.05).In the conventional incision group,IOL was displaced in 18 eyes due to the shallow anterior chamber and then returned to normal after the formation of the anterior chamber through a watertight incision during surgery;during the formation,iris prolapse and incarceration occurred in 2 eyes,and IOL rotation or incarceration occurred in 3 eyes.In the trapezoidal incision group,3 eyes had a shallow anterior chamber after surgery,and a watertight incision was used to form the anterior chamber;there was no IOL incarceration or displacement or iris prolapse.Conclusion The improved trapezoidal transparent corneal incision can effectively prevent IOL displacement caused by anterior chamber collapse during cataract surgery while ensuring the stability of the anterior chamber.It can also reduce the related complications caused by the watertight incision using a flushing needle and restore patients'vision as early as possible.

Abstract： Objective　To elucidate the antigenic antibody reaction of recombinant expression of non-structural protein 1 (NS1) of Japanese encephalitis (JE) virus with various mosquito-borne flaviviruses, including JE virus, and the antigenic antibody reaction of serum samples of patients infected with JE virus in acute stage. Methods　In this study, Escherichia coli prokaryotic expression vector (pET) system was used to recombinant express Japanese encephalitis virus NS1 gene. Western Blot assay was performed to detect the antibody responses of the recombinantly expressed protein against a variety of mosquito-transmitted flaviviruses, including JE virus, as well as antigen-antibody reactions of serum from patients with acute JE virus infection. Results　The NS1 gene expression product of JE virus (P3 strain) was in the form of an inclusion body, and the denatured and renatured expression product was displayed as a single band in the denatured gel (polyacrylamide gel electrophoresis, PAGE), with a molecular weight of about 45 000. The results of further antigen-antibody analysis showed that the antigen/antibody hybridization reaction of the expression product with polyclonal or monoclonal antibody of JE virus (mosquito isolates, encephalitis isolates) and serum samples of patients with acute JE virus infection could be completely consistent. The recombinant product showed negative antigen/antibody hybridization reactions with mosquito-transmitted flaviviruses, such as dengue virus and yellow fever virus polyclonal antibodies, but positive reactions with polyclonal antibodies to West Nile virus and Murray Valley encephalitis virus. Conclusions　In this study, the recombinant expression of the NS1 protein of JE virus was successfully obtained, and the antigen/antibody reaction between the recombinant protein and samples of patients infected with mosquito-borne flavivirus and JE virus was analyzed. The study results provide important basic data for elucidating the antigen-antibody reaction between the NS1 protein of JE virus and mosquito-borne flavivirus. The recombinant expression protein obtained in this study provides an important material basis for further research on the function of JE virus NS1 protein.

Objective:To analyze the etiological and epidemiological characteristics of hand, foot and mouth disease (HFMD) in Xi′an from 2019 to 2021, so as to provide evidence for the prevention and control of HFMD.Methods:Stool specimens and anal swabs were collected from patients with HFMD. Enteroviruses (EVs) including enterovirus 71 (EV71), coxsackievirus A16 (CVA16), CVA6 and CVA10 were detected by RT-PCR. Excel 2007 and SPSS18.0 software were used for data collection and statistical analysis, respectively. The epidemiological data of HFMD cases were analyzed by descriptive epidemiology method. The VP1 gene sequence of the representative strain of each CVA6 genotype was downloaded. Phylogenetic trees were constructed using MEGA X software and the genetic characteristics were analyzed.Results:A total of 1 531 HFMD cases were involved and 1 365 were positive for EVs with a positive rate of 89.16%. The detection rates of EV71, CVA16, CVA6, CVA10 and other EVs were 1.31% (20/1 531), 32.46% (497/1 531), 38.47% (589/1 531), 5.09% (78/1 531) and 11.23% (172/1 531), respectively. There were significant differences in the pathogen composition in HFMD cases of different clinical types (χ 2=46.14, P<0.01) and occupations (χ 2=34.65, P<0.01) as well as in different years (χ 2=462.86, P<0.01). The average age was greater in patients with CVA16 infection than in those with CVA6 or CVA10 infection ( F=6.00, P<0.01). In 2019, the HFMD cases were mainly caused by CVA16, while in 2020 and 2021, the main pathogen was CVA6. Enterovirus-positive cases showed a bimodal distribution with the main peak from May to July and the secondary peak from September to November. CVA16 was the predominant pathogen in spring and summer, and CVA6 was the predominant pathogen in autumn. CVA6 was the dominant pathogen in eight districts and counties of Xi′an; CVA16 was the dominant pathogen in six districts and counties; CVA6 and CVA16 co-circulated in one district. The CVA6 isolates belonged to two evolutionary branches of D3a subtype. Conclusions:CVA6 and CVA16 were the prevalent pathogens of HFMD and CVA6 subtype D3a circulated in Xi′an from 2019 to 2021. The pathogen composition of HFMD cases showed obvious differences in population, time and regional distribution.

Objective:To investigate the molecular epidemiological characteristics and antibiotic resistance of Clostridioides difficile ( Cd) in hospitalized diarrhea patients in a tertiary hospital in Shaanxi Province. Methods:This study collected 425 stool samples of hospitalized diarrhea patients from October 2018 to December 2021 for isolation and identification of Cd. Toxin genes carried by the isolates were detected. Multilocus sequence typing (MLST) was performed to analyze the phylogenetic profile. Antibiotic susceptibility was analyzed by E-test. Results:Forty-nine strains of Cd were isolated from the 425 samples, including 37 strains of toxigenic Cd (75.5%, 37/49). The detection rate of Cd was 14.0% (25/179) in diarrhea patients aged ≥65 years old and 36.4% (4/11) in Nephrology Department. In the 37 toxigenic Cd strains, A -B + CDT -Cd, A + B + CDT -Cd and A + B + CDT +Cd accounted for 18.9% (7/37), 78.4% (29/37) and 2.7% (1/37), respectively. There were 24 ST types, among which ST2, ST3 and ST54 were the predominant types, each accounting for 12.2% (6/49). All strains were sensitive to metronidazole and vancomycin, with a high resistance rate of 93.9% (46/49) to ciprofloxacin and a low resistance rate of 12.2% (6/49) and 10.2% (5/49) to rifampicin and meropenem, respectively. Conclusions:The main type of toxigenic strains was A + B + CDT -. ST2, ST3 and ST54 were the predominant types and the distribution of ST types was scattered. All isolates were sensitive to metronidazole and vancomycin and most of them were resistant to ciprofloxacin.

【Objective】 To compare the macrolide resistance, molecular characteristics and multilocus antigen sequence typing (MAST) of Bordetella pertussis (Bp) collected from Xi’an and Shanghai so as to provide reference for prevention of pertussis and optimize vaccination strategies. 【Methods】 Erythromycin, azithromycin and clarithromycin susceptibility of clinical isolates collected from Xi’an and Shanghai during 2018 and 2019 were determined by E-test. PCR was used to detect the drug-resistant genes and mutation sites. MAST was employed to do molecular typing for the strains. The differences in macrolide resistance and MAST types between Xi’an and Shanghai were compared. 【Results】 Totally 34 strains from Xi’an and 26 strains from Shanghai were isolated. There were differences between Xi’an and Shanghai in the macrolide resistance (χ²=13.650, P<0.001). The composition ratio of MAST types of pertussis strains was also different between Xi’an and Shanghai (χ²=18.642, P<0.001) in that the prn1/ptxP1/ptxA1/fim3-1/fim2-1 strains dominated in Xi’an, while the prn1/ptxP1/ptxA1/fim3-1/fim2-1 and prn2/ptxP3/ptxA1/fim3-1/fim2-1 were almost half and half in Shanghai. A2047G site mutation was detected in all the macrolide-resistant strains, but not in all sensitive strains. Methylase genes ermA and ermB were detected in some macrolide-resistant strains. No other macrolide-resistant genes were found in resistant strains and no mutation or drug resistance gene was found in all the susceptible strains. 【Conclusion】 Differences existed between Xi’an and Shanghai in the macrolide resistance and MAST types of Bordetella pertussis strains. Further monitoring of Bordetella pertussis in China is required to better understand the resistance and evolution of the pathogen.

Objective:To characterize the epidemiology of hand, foot and mouth disease (HFMD) cases caused by coxsackievirus group A type 6 (CV-A6) in Xi’an from 2016 to 2020 and provide evidence for the prevention and control of HFMD.Methods:The enterovirus (EV) types were identified using real-time RT-PCR. The data of HFMD cases were collected from the National Notifiable Infectious Diseases Reporting System of China Center for Disease Control and Prevention. Descriptive epidemiological method were used to analyze the distributions and the data were statistically analyzed with Excel 2007 and SPSS 18.0.Results:In the 4 034 HFMD cases, 17.85% had enterovirus group A type 71 (EV-A71) infections, 23.92% had coxsackievirus group A type 16 (CV-A16) infections, and 47.79% had other EV infections. 2 571 HFMD cases were randomly selected, including 1 268 other EV positive cases. The detection rate of CV-A6 in HFMD cases was 34.73% (893/2 571), and the constituent ratio of CV-A6 in other EV positive cases was 70.43% (893/1 268). The cases mainly occurred in children aged≤5 years (95.18%), more boys were affected than girls (1.47∶1). HFMD caused by CV-A6 was concentrated in April to June. Compared with EV-A71 and CV-A16, the clinical classification had significant difference in CV-A6 group ( χ2=139.55, P<0.001), but the ratio of sex and age-group had no significant difference ( F=2.74, P=0.065; χ2=2.43, P=0.297). Conclusions:The predominant pathogen of HFMD in Xi’an from 2016 to 2020 were other EV, among which CV-A6 accounted for the highest proportion in other EV positive cases. It is necessary to strengthen the prevention and control of HFMD caused by CV-A6 and carry out the surveillance for various pathogens of HFMD.