[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.

[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.

[Pathological observation of lung injury in experimental animals induced by non-ferrous metal (tin) dusts].

OBJECTIVE: To explore the characters of lung injury induced by tin dusts and to provide the diagnosis evidence of tin pneumoconiosis. METHODS: Forty SD rats were randomly divided into four groups: the group exposed to tin dusts from smelting workshop, the group exposed to tin dusts from tin refining workshop, the positive control group exposed to standard quartz dusts and the negative control group exposed to saline. The pathological changes of rat lungs were observed dynamically. RESULTS: In rats exposed to tin dusts, on the 30th day after exposure to tin dusts, the scattered hoar tip size of the spots in surface and section of the lungs were observed, the scattered focal granulomatous inflammation around the small bronchi and dust particles in lung tissue were observed under microscope; on the 90th day after exposure to tin dusts, the granulomatous inflammation increase, the fibroblasts proliferation, collagen fibers formation and positive VG staining were found. There were significant differences, as compared with positive or negative controls (P < 0.05). These pathological changes were basically the characters of specific pathological changes in early tin pneumoconiosis. CONCLUSION: Non-ferrous metal tin dusts can induce the specific lung injury (granuloma formation) in lung tissue of rats exposed to tin dusts, which fulfilled the diagnostic criteria of specific pathological changes in early tin pneumoconiosis.

Hepatitis B virus genotypes, phylogeny and occult infection in a region with a high incidence of hepatocellular carcinoma in China.

AIM: To determine the genotypes and phylogeny of hepatitis B viruses (HBVs) in asymptomatic HBV carriers, and the prevalence of occult HBV infection in Long An County, Guangxi Zhuang Autonomous Region, an area with a high incidence of hepatocellular carcinoma. METHODS: A nested polymerase chain reaction (nPCR) was used for detection of HBV DNA in serum samples from 36 blood donors with asympmatic HBV infection, and in serum samples from 52 HBsAg negative family members of the children who did not receive hepatitis B vaccination in Long An County. PCR products were sequenced, and the genotype of each HBV sequence was determined by comparison with sequences of known genotypes in the GenBank and EMBL nucleotide databases using the BLAST programme. Phylogenetic trees were constructed by the quartet maximum likelihood analysis using the TreePuzzle software. RESULTS: Twenty (55.56%) of 36 HBV asymptomatic carriers were positive for HBV DNA. They were all genotype C by comparison with sequences of known genotypes in the GenBank and EMBL nucleotide databases. The full-length HBV DNA sequence isolated from the sample No. 624 contained 3 215 bases. No interesting mutations were found in this isolate. The homology analysis showed that this strain was closer to the Vietnamese HBV genotype C strain, with a homology of 97%, compared its relation to the same genotype of HBV isolated in Shanghai. Six (11.5%) of the 52 HBsAg negative family members were positive for HBV DNA. A point mutation was found in the sample No. 37, resulting in the substitution of amino acid glycine to arginine in the "a" determinant. Other samples with positive HBV DNA did not have any unusual amino acid substitutions in or around the "a" determinant, and were attributed to the wild-type HBV. CONCLUSION: The HBVs isolated from asymptomatic carriers of Long An County were all identified as genotype C, and the prevalence of occult HBV infection in the population of the county is as high as 11.5%. It is suggested that genotype C and persistent occult HBV infection may play an important role in the development of HCC in the county.

[Full-length sequence of hepatitis B virus isolated from high incidence hepatocellular carcinoma area-Longan county].

OBJECTIVE: To understand full-length sequence of HBV isolated from high incidence hepatocellular carcinoma area-Longan county, Guangxi. METHODS: The nested polymerase chain reaction (nPCR) was used for amplifying the whole HBV DNA in sera of asymptomatic carriers. The products were sequenced by clone sequencing and homological analysis. RESULTS: This isolate contained 3 215 bases. The genotype was C and the serotype was adw. There were 40 point mutations in polymerase gene which made 11 amino acids change. There were 11,2 and 3 point mutations in PreS1, PreS2 and S gene respectively which made 3,1,1, amino acids change. Six point mutations including the double mutations (nt 1762 A to T, 1764 G to A) were found in X gene leading to 4 amino acids change. There were 13 point mutations in C gene which made 2 amino acids change. No mutation was found in a determinant and Pre C. The isolate was quite close to the isolate from Vietnamese in evolution while far from the genotype C isolates from Shanghai, Beijing and Tibet. CONCLUSION: No special sequence was found in the isolate from high incidence hepatocellular carcinoma area, Longan county, Guangxi.

[Core promoter mutations of HBV isolated from patients with chronic hepatitis B in Guangxi].

OBJECTIVE: To explore the relationship between HBV core promoter mutations and liver damage or HBeAg status. METHODS: Nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA core promoter in 59 sera from patients with chronic hepatitis B in Guangxi, then the HBV DNA positive products were sequenced by direct sequencing. RESULTS: The HBV DNA positive rate of was 59.3%(35/59). All the patients were infected by mutants. The commonest mutation was the double mutation (A --> T at nt1762 and G --> A at nt1764), counting for 57.1% (20/35). The next was C --> G at nt1799, counting for 54.4% (19/35), but this was no function. A --> G at nt1752 (resulting in isoleucine to valine) was seen in 37.1% (13/35) of the HBV DNA positive patients, and T --> C at nt1753 was seen in 20% (7/35). The significant difference in the frequency of T1762A1764 mutant was found between HBeAg positive patients (31.3%) and negative patients (79.0%). CONCLUSIONS: HBV core promoter mutations are common among patients with chronic hepatitis B in Guangxi. T1762A1764 mutant is associated with HBeAg status and chronic hepatitis.

[Prevalence of hepatitis B virus core promoter mutant isolated from asymptomatic carriers from areas with higher and lower incidence of hepatocellular carcinoma in Guangxi].

OBJECTIVE: To understand the prevalence of HBV core promoter mutant (T1762 A1764 mutant) isolated from asymptomatic carriers from areas with higher and lower incidence of hepatocellular carcinoma (HCC) in Guangxi. METHODS: A nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA core promoter in sera, and then HBV DNA nPCR products were sequenced by direct sequencing. RESULTS: The results show that 50.6% (39/77) of all HBV asymptomatic carriers were positive for HBV DNA HBV DNA positive rates of the samples from HCC higher incidence area, Longan County, and from lower incidence area, Guilin city were 55.6% (20/36) and 46.3% (19/41), respectively. HBV core promoter mutants could be seen in 35% in Longan positive samples and 47.4% in Guilin. The common mutations in both regions were all double mutations (nt 1,762 A-->T; nt 1,764 G-->A), accounting for 25% and 21%, respectively. The difference of the double mutant between Longan County and Guilin city was not significant (P>0.05). CONCLUSIONS: These data implicated that the prevalence of HBV core promoter mutant isolated from asymptomatic carriers may not be correlated with the incidence of HCC in Guangxi.

[Distribution of hepatitis B virus genotypes and its clinical significance in Guangxi].

OBJECTIVE: To understand the distribution of hepatitis B virus genotype in Guangxi and its clinical significance. METHODS: Nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA in sera of asymptomatic carrier (ASC) of hepatitis B virus (HBV) and patients with different liver diseases from southern and northern Guangxi. Specimens from 161 subjects were positive for HBV DNA and HBV genotype was determined by using restriction fragment length polymorphism analysis, direct sequencing or cloning sequencing. RESULTS: The prevalence of genotype A was 3.7% in all samples and that of genotype B, C and D was 21.7%, 72.7% and 1.2%, respectively. No other genotypes (such as genotype E, F, G, H) were found. The prevalence of genotype C showed an increasing trend in ASC, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC) group; in contrast, the prevalence of genotype B showed an opposite trend, although no statistically significant difference was observed, except between ASC and HCC (P=0.05). The HBeAg positive rate was higher, and the anti-HBe positive rate was lower in patients with chronic genotype C infection than in those with genotype B (P<0.05 for both). Liver function test (ALT) abnormality was more severe in genotype C group than in genotypes A and B groups having acute or chronic infection (P<0.01 for all comparisons). The prevalence of genotype C in southern Guangxi was higher than that in northern Guangxi. In contrast, the prevalence of genotype B in southern Guangxi was lower than that in northern Guangxi. CONCLUSIONS: 1. The predominant HBV genotypes in Guangxi were genotypes B and C. The major genotype in southern Guangxi was genotype C; while that in northern Guangxi was genotype B, which implied that the distribution of HBV genotype C was consistent with the incidence of HCC in Guangxi. 2. Genotype C maybe associated with development of severe liver diseases including HCC. 3. Genotype A,D and B+C were mostly found in acute, hepatitis and chronic hepatitis group.

[Human hepatitis B virus infection of tree shrews and Macaca assamensis in vivo].

OBJECTIVE: To examine sensitivity of the tree shrews and Macaca assamensis to human hepatitis B virus (HHBV) by serologic methods. METHODS: Totally 233 tree shrews and 28 Macaca assamensis were inoculated with human sera containing HBV. After inoculation, the sera were collected weekly from them and HBV markers were detected with HBV ditecting ELISA kits. RESULTS: Ninety percent of the tree shrews developed acute infection, among them, 44.4 % persisted for over one year, 33.3% of them developed chronic infection persisted for 2 years and one month; the persistence of HBV in Macaca assamensis was much shorter. CONCLUSION: These data clearly indicated that tree shrew may be used as an animal model for study of chronic HBV infection, whereas, Macaca assamensis, showed only a transient sensitivity to HHBV.