[Genetic Subtypes and Pretreatment Drug Resistance in the Newly Reported Human Immunodeficiency Virus-Infected Men Aged≥50 Years Old in Guangxi].

Objective To analyze the genetic subtypes of human immunodeficiency virus (HIV) and the prevalence of pretreatment drug resistance in the newly reported HIV-infected men in Guangxi. Methods The stratified random sampling method was employed to select the newly reported HIV-infected men aged≥50 years old in 14 cities of Guangxi from January to June in 2020.The pol gene of HIV-1 was amplified by nested reverse transcription polymerase chain reaction and then sequenced.The mutation sites associated with drug resistance and the degree of drug resistance were then analyzed. Results A total of 615 HIV-infected men were included in the study.The genetic subtypes of CRF01_AE,CRF07_BC,and CRF08_BC accounted for 57.4% (353/615),17.1% (105/615),and 22.4% (138/615),respectively.The mutations associated with the resistance to nucleoside reverse transcriptase inhibitors (NRTI),non-nucleoside reverse transcriptase inhibitors (NNRTI),and protease inhibitors occurred in 8 (1.3%),18 (2.9%),and 0 patients,respectively.M184V (0.7%) and K103N (1.8%) were the mutations with the highest occurrence rates for the resistance to NRTIs and NNRTIs,respectively.Twenty-two (3.6%) patients were resistant to at least one type of inhibitors.Specifically,4 (0.7%),14 (2.3%),4 (0.7%),and 0 patients were resistant to NRTIs,NNRTIs,both NRTIs and NNRTIs,and protease inhibitors,respectively.The pretreatment resistance to NNRTIs had much higher frequency than that to NRTIs (2.9% vs.1.3%;χ2=3.929,P=0.047).The prevalence of pretreatment resistance to lamivudine,zidovudine,tenofovir,abacavir,rilpivirine,efavirenz,nevirapine,and lopinavir/ritonavir was 0.8%, 0.3%, 0.7%, 1.0%, 1.3%, 2.8%, 2.9%, and 0, respectively. Conclusions CRF01_AE,CRF07_BC,and CRF08_BC are the three major strains of HIV-infected men≥50 years old newly reported in Guangxi,2020,and the pretreatment drug resistance demonstrates low prevalence.

2B and 3C Proteins of Senecavirus A Antagonize the Antiviral Activity of DDX21 via the Caspase-Dependent Degradation of DDX21.

Senecavirus A (SVA), also known as Seneca Valley virus, is a recently discovered picornavirus that can cause swine vesicular disease, posing a great threat to the global swine industry. It can replicate efficiently in cells, but the molecular mechanism remains poorly understood. This study determined the host's differentially expressed proteins (DEPs) during SVA infection using dimethyl labeling based on quantitative proteomics. Among the DE proteins, DDX21, a member of the DEAD (Asp-Glu-Ala-Asp)-box RNA helicase (DDX) family, was downregulated and demonstrated inhibiting SVA replication by overexpression and knockdown experiment. To antagonize this antiviral effect of DDX21, SVA infection induces the degradation of DDX21 by 2B and 3C proteins. The Co-IP results showed that 2B and 3C did not interact with DDX21, suggesting that the degradation of DDX21 did not depend on their interaction. Moreover, the 3C protein protease activity was necessary for the degradation of DDX21. Furthermore, our study revealed that the degradation of DDX21 by 2B and 3C proteins of SVA was achieved through the caspase pathway. These findings suggest that DDX21 was an effective antiviral factor for suppressing SVA infection and that SVA antagonized its antiviral effect by degrading DDX21, which will be useful to guide further studies into the mechanism of mutual regulation between SVA and the host.

[Effects of Human Immunodeficiency Virus-positive Mothers Receiving Antiretroviral Therapy to Prevent Mother-to-child Transmission on the Growth and Development of 18-month-old Children in Lingshan County of Guangxi].

Objective To evaluate the effects of antiretroviral therapy(ART)for the prevention of mother-to-child transmission(PMTCT)of acquired immune deficiency syndrome(AIDS)on the growth and development of 18-month-old children born by human immunodeficiency virus(HIV)-positive pregnant women in Lingshan County,Guangxi Zhuang Autonomous Region,and provide scientific evidence for improving the ART medication plan for PMTCT.Methods Lingshan County,ranking the first in the HIV-epidemic counties of Guangxi,was selected as the research site.According to the design of retrospective case-control study,we assigned all the subjects into the case group and the control group:(1)The case group included the HIV-positive pregnant women who had received ART for PMTCT and their HIV-negative infants in Lingshan County from 2010 to 2017.The historical cards and PMTCT data of them were collected from the national PMTCT database.(2)The control group included the healthy pregnant women and their healthy babies born in the Lingshan Maternity and Infant Hospital in 2017,and the children's growth and development data were collected.The stunted growth in children was defined as at least one of the three main indicators of body height,body weight,and head circumference below the normal range.Results The number of HIV-positive mothers and their infants in the case group was 391 and 368,respectively,and 87.21%(341/391)and 95.38%(351/368)of mothers and infants respectively received ART medication.The HIV positive rate,mortality rate,and mother-to-child transmission rate of 18-month-old children were 1.36%(5/368),4.35%(16/368),and 2.01%(5/249),respectively.The incidence of stunted growth of 18-month-old children in the case group and the control group was 42.12%(155/368)and 23.06%(101/438),respectively,with significant difference(χ2=33.520,P<0.001).Conclusion After HIV-positive mothers in Lingshan County of Guangxi received ART for PMTCT,the incidence of growth stunting in 18-month-old children increased.