Objective This study aimed to investigate the effects of Aβ3-10KLH active immunization on brain aging in the SAMP8 rapid aging mouse model using oxidative stress as the entry point.Methods SAMP8 mice were immunized with the Aβ3-10KLH vaccine,and a control group was established.Behavioral changes were observed using the Morris water maze test,and hippocampal morphological changes were examined using hematoxylin and eosin staining.The proportion of senescent cells in the hippocampus was detected using SA-β-gal staining.Biochemical kits were used to measure the changes in oxidative stress injury indicators malondialdehyde(MDA)and superoxide dismutase(SOD)activities to assess oxidative stress damage in the hippocampus.Results The Aβ3-10KLH vaccine attenua-ted cellular aging in the hippocampi of SAMP8 mice.It also improved memory ability(P＜0.05),ameliorated hippocampal tissue mor-phology,decreased the proportion of senescent cells in the hippocampus(P＜0.05),lowered MDA content(P＜0.05),and upregulated SOD activity(P＜0.05).Conclusion The Aβ3-10KLH vaccine significantly improves cognitive function in SAMP8 mice,slows down the aging of hippocampal neurons,and reduces oxidative stress damage.

Objective:To study the epidemic characteristics of kala-azar in Shaanxi Province, and to provide scientific basis for formulating effective prevention and control measures.Methods:Information of kala-azar confirmed cases and clinically diagnosed cases whose current addresses were reported in Shaanxi Province in the Surveillance Report Management System of China Disease Control and Prevention Information System from 2011 to 2022 was collected. Trend analysis was made on the number of cases in each year, and descriptive epidemiological methods were used to analyze the onset time, regional and population distribution characteristics and the time interval from onset to diagnosis of kala-azar cases.Results:A total of 225 kala-azar cases were reported in Shaanxi Province from 2011 to 2022, and the number of cases showed an increasing trend (χ 2trend = 98.50, P < 0.001), with the highest number in 2020 (42 cases). The onset time was mainly from March to May (77 cases, 34.22%). The top three cities with the number of reported cases were Hancheng (65 cases, 28.89%), Shangluo (47 cases, 20.89%) and Weinan cities (44 cases, 19.56%). The male to female ratio was 1.74∶1.00 (143/82), the age of onset was mainly concentrated in the age group of 36 - 60 years old (111 cases, 49.33%), and the occupation was mainly farmers (150 cases, 66.67%). The median interval from onset to diagnosis was 11 days, and 78.22% (176/225) of the cases were diagnosed within 1 month. Conclusions:From 2011 to 2022, the overall incidence of kala-azar in Shaanxi Province has showed an upward trend, with the main population being middle-aged male farmers. The main affected areas are Hancheng, Shangluo and Weinan cities. It is urgent to strengthen the surveillance and prevention and control of kala-azar in key populations and key regions.

Objective:To analyze the clinical features, treatment, pathology and prognosis of retroperitoneal paraganglioma(PGL).Methods:Surgery adopted, pathology and follow-up data of patients with retroperitoneal PGL at the First Affiliated Hospital of Zhengzhou University from Jan 2015 to Jan 2022 were retrospectively analyzed.Results:Compared with non-functional PGL patients, those with functional PGL had higher systolic and diastolic blood pressure (180 mmHg vs. 140 mmHg, Z=-4.807, P<0.001;100 mmHg vs. 82 mmHg, Z=-4.495, P<0.001)at admission, and were more prone to hemodynamic instability during operation ( χ2=8.188, P=0.004). All 65 patients under wentresection,with partial excision and repair of inferior vena cava in 1 patient . Sixty-two patients out of 65 were followed up, and 4 patients died of disease progression. The overall 5-year survival rate was 92%. The prognosis of patients with G3 tumor and distant metastasis was poor , the difference was statistically significant ( χ2=4.259, P=0.039; χ2=13.061, P<0.001). Tumor diameter and tumor functional status were not related to the prognosis, and the difference was not statistically significant ( χ2=0.519, P=0.472; χ2=0.010 P=0.920). Conclusions:Retroperitoneal PGL is less common, and some may encroach abdominal large vessels. The prognosis is good after complete resection of the tumor. Distant metastasis and G3 tumors are associated with poor prognosis .

Alzheimer's disease (AD) is a progressive neurodegenerative disease with memory impairment as the main manifestation. With the development of an aging society,the incidence of AD is on the rise,bringing a huge social and economic burden. In recent years,the classical amyloid cascade hypothesis in the pathogenesis of AD has been challenged,and the toxic effects of Aβ oligomers (AβOs) have been consistently recognized,which may be a trigger for the pathogenesis of AD. The specific source,structure,and pathogenic mechanism of Aβ oligomers are not fully understood. It is possible that different types of oligomers are not consistent in pathogenicity and toxicity,and their mechanisms of action are different. This article reviews the recent understanding of Aβ oligomers,as well as their structural characteristics and pathogenic effects,to better understand the relationship between Aβ oligomers and AD,and provide possible directions for future research.

【Objective】 To investigate the unqualified rate of anti-HIV detection of blood screening laboratories in Beijing-Tianjin-Hebei region, and explore the differences in anti-HIV detection ability and influencing factors in each laboratory. 【Methods】 Through filling questionnaires via e-mail, the anti-HIV ELISA unqualified rate and confirmed (WB) positive results (data) from January to December 2018 from 15 blood screening laboratories in Beijing-Tianjin-Hebei region were collected. Our laboratory was responsible for data collection and confirmation, and statistics software SPSS22.0 was used for analysis. 【Results】 1) There was a statistically significant difference among the unqualified rate of anti-HIV ELISA(6.77‱~35.71‱) and confirmed positive rate(0.60‱~3.56‱) in 15 blood screening laboratories in Beijing-Tianjin-Hebei region (P<0.05); 2) There were significant differencse among the ELISA unqualified rate and the confirmed positive rate of 8 reagents for anti-HIV detection(P<0.01), and the sensitivity of the 4th generation detection reagent and the imported reagent was higher than that of the 3rd generation reagent and the domestic reagent. The anti-HIV ELISA unqualified rate of R5 was the highest (19.08‱). 3)There were significant differences in the anti-HIV ELISA unqualified rate of R1, R2, R3, R5 and R7 reagents among different blood station laboratories(P<0.05), and there were no significant differences in the anti-HIV ELISA unqualified rate of R4, R6 and R8 reagents among different blood station laboratories(P>0.05). 4)The unqualified rate of anti-HIV ELISA of laboratories using different regents showed significant differences(P<0.05), except H, J, M. The unqualified rate of imported reagent was significantly higher than that of domestic reagents of laboratories using imported and domestic reagents combinations(P<0.05), except O. 62.5% (5/8) laboratories using domestic 3^rd and 4^th generation reagent combination showed significant differences in the unqualified rates among different reagents(P<0.05); 5) The positive rate of single-reagent(62.02%~95.45%)in 15 blood screening laboratories showed significant difference(P<0.001), and A was the lowest (62.02%). 【Conclusion】 The anti-HIV detection ability among 15 blood screening laboratories in Beijing-Tianjin-Hebei region is quite different. The application of different reagents is the main factor for the difference, and other factors such as personnel, instruments and test strategies also has a great impact on the detection of anti-HIV. It is still necessary to promote the process of homogenization of blood testing quality among blood screening laboratories in Beijing-Tianjin-Hebei region.

【Objective】 To assess the epidemiological characteristics and transmission risk of asymptomatic COVID-19 infection in Shaanxi Province. 【Methods】 A dense population database of COVID-19 cases in Shaanxi Province was constructed as of March 26, 2020, and 28 asymptomatic infected patients were selected through case epidemiological investigation report for descriptive analysis. 【Results】 In Shaanxi Province, the majority of asymptomatic COVID-19 infections were in the 20-59 years old group, and women took up a higher proportion than men. 82.14% of asymptomatic infections were found in the centralized isolation state. Nearly 80% of asymptomatic infections and confirmed cases were mainly exposed by living together in the family. The median number of days from last contact with the source of infection for all asymptomatic infected persons was 13, with 3 (10.71%) showing clinical symptoms. Epidemiological investigations showed that asymptomatic infections could spread as a result of shared family life. 【Conclusion】 At present, imported cases in Shaanxi Province continue to exist. Considering the concealed transmission of asymptomatic infections, prevention and control work is still facing challenges.

Objective:By analyzed the transmission patterns of 4 out of the 51 COVID-19 cluster cases in Shaanxi province to provide evidences for the COVID-19 control and prevention.Methods:The epidemiological data of RT-PCR test-confirmed COVID-19 cases were collected. Transmission chain was drawn and the transmission process was analyzed.Results:Cluster case 1 contained 13 cases and was caused by a family of 5 who traveled by car to Wuhan and returned to Shaanxi. Cluster case 2 had 5cases and caused by initial patient who participated family get-together right after back from Wuhan while under incubation period. Cluster case 3 contained 10 cases and could be defined as nosocomial infection. Cluster case 4 contained 4 cases and occurred in work place.Conclusion:Higher contact frequency and smaller places were more likely to cause a small-scale COVID-19 cluster outbreak, with potential longer incubation period. COVID-19 control strategies should turn the attention to infection prevention and control in crowded places, management of enterprise resumption and prevention of nosocomial infection.

Objective:To understand the incidence trend and epidemiological characteristics of COVID-19 in Shaanxi province.Methods:The incidence data of COVID-19 reported in Shaanxi as of 22 February, 2020 were collected for an epidemiological descriptive analysis.Results:A total of 245 confirmed cases of COVID-19 were reported in Shaanxi. Most cases were mild (87.76%). As time passed, the areas where confirmed cases were reported continued to increase. The case number in Xi’an was highest, accounting for nearly half of the total reported cases in the province. The epidemic pattern in Shaanxi had gradually shifted from imported case pattern to local case pattern, and the transmission of local cases was mainly based on family cluster transmission. The confirmed cases from different sources had caused the secondary transmission in Shaanxi. After February 7, the number of reported cases began to fluctuate and decrease stably, indicating a decrease-to-zero period.Conclusions:At present, the overall epidemic of COVID-19 in Shaanxi has gradually been mitigated. However, considering the approaching of return to work and study and the increasing of imported cases from other countries, the prevention and control of COVIS-19 in Shaanxi will face new challenges.

A total of 245 cases of COVID-19 in Shaanxi Province reported in the China information system for disease control and prevention as of February 24, 2020 were selected as the research objects, the cases are divided into imported cases (116 cases, 47.3%) and local cases (129 cases, 52.7%), their basic characteristics, time distribution, transmission mode, intergenerational interval and latent period transmission are analyzed. The age of local cases [(51.74±15.67) years old], female patients (69 cases, 53.5%), housework and retired staff (40 cases, 31.0%), and patients isolated at the time of onset (50 cases, 38.8%) were higher than imported cases, respectively[(40.66±15.41) years old, (45 cases, 38.8%), (21 cases, 18.1%), (17 cases, 14.6%)] ( P values were < 0.05); The infection rate was 0.8% (31/3 666) in close contacts with local cases, which was lower than imported cases 2.0% (69/3 435) ( P<0.001); The main source of infection in local cases was relatives (70 cases, 54.3%), and the main way of infection was living together and party (90 cases, 69.8%); the proportion of latent period transmission in our province was 15.5% (20 cases), and the interval between the second-generation case and the source of infection was about 4 days, and the interval between generations was about 6 days. In summary, the main way of infection of local cases in Shaanxi Province was living together and party, there were a certain proportion of latent period transmission cases at present, it's suggested that the investigation of close contacts should be started 4 days or earlier before the onset of the case.