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1.
Transl Pediatr ; 13(7): 1130-1140, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39144422

RESUMEN

Background: Astigmatism is closely associated with myopia progression, vision loss, eye fatigue and amblyopia, which seriously endangers children's eye health. This study aims to investigate the prevalence and characteristic distribution of astigmatism in children in Langzhong City, providing valuable insights for allocating resources and develop prevention and control strategies. Methods: A cross-sectional study and random sampling survey were conducted. Between January and November 2021, 21,415 students aged 5 to 13 years from 14 primary schools in Langzhong City underwent non-cycloplegic refractive testing using autorefraction. The data on myopia were analyzed using SPSS (Statistical Package for the Social Sciences) version 23.0. Results: The inclusion criterion was set at an absolute astigmatism value of ≥0.50D. Among the 21,415 children studied, 61.70% were found to have astigmatism. The prevalence of astigmatism varied significantly across different grades (χ2=501.414, P<0.001). The predominant types of astigmatism were mild astigmatism (0.50-1.00D) and with-the-rule astigmatism. Mixed astigmatism was primarily observed in children in grades 1 and 2, while compound myopic astigmatism was more common in children in grades 3 to 6. These differences were statistically significant. As the degree of astigmatism increased, the proportions of against-the-rule astigmatism, oblique astigmatism, compound myopic astigmatism, and simple hyperopic astigmatism decreased, whereas the proportions of with-the-rule astigmatism, mixed astigmatism, and compound hyperopic astigmatism increased. Conclusions: The prevalence of astigmatism among school-age children aged 5 to 13 years in northeast Sichuan is notably high, with compound myopic astigmatism and with-the-rule astigmatism being the most common types. Regular refractive examinations are crucial for the early detection and management of astigmatism.

2.
Indian J Ophthalmol ; 72(Suppl 3): S415-S422, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38324629

RESUMEN

PURPOSE: In this study, we examined the current status of myopia among primary and secondary school children in northeastern Sichuan to analyze the factors connected to myopia and provide data support and a theoretical foundation for the prevention and control of myopia. METHODS: Using a cross-sectional study and a comprehensive sampling survey, 34,138 students aged 5-19 years were screened for refraction in 22 primary and secondary schools in Langzhong, and 4000 behavioral questionnaires were delivered at random. After evaluation and rational problem-solving, a total of 3764 valid questionnaires were obtained. SPSS 23.0 statistical software was used for data analysis. RESULTS: The percentage of myopia among primary and secondary school students in Langzhong was 65.61%, with female students having a higher rate than male students ( P < 0.05); 52.81% of primary school students, 86.26% of secondary school students, and 88.17% of high school students had myopia. The incidence of myopia detection increased with school age ( P < 0.001), indicating a correlation between age and myopia prevalence. The prevalence of myopia was mainly low (40.53%) and moderate myopia (19.89%). The prevalence of high myopia (5.19%) was relatively high. The prevalence of myopia among female students (5.54%) was greater than that in male students ( P < 0.05) and increased with age ( P < 0.001). The proportion of students who wore eyeglasses was 24.36%, with a larger proportion of female students (25.93%) than male students (22.61%) ( P < 0.001). In addition, the rate of eyeglass use increased with school age ( P < 0.001). A logistic regression analysis revealed that higher grade point averages, female gender, and long-term usage of electronic items were risk factors for myopia. The results of the questionnaire survey revealed that students in this region were under immense pressure to perform well academically, spent a lot of time engaged in near-work activities, and had a low rate of myopia awareness; 24.43% of the students had not had a vision examination in the previous year, indicating that parents did not pay sufficient attention to eye health. CONCLUSION: The incidence of myopia among children and teenagers is high in Northeast Sichuan, and the outlook for addressing the problem is bleak. Therefore, it is critical to improve vision monitoring and eye health education.

3.
Virology ; 586: 23-34, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37478771

RESUMEN

Current therapies control but rarely achieve a cure for hepatitis B virus (HBV) infection. Restoration of the HBV-specific immunity by cell-based therapy represents a potential approach for a cure. In this study, we generated HBV specific CAR T cells based on an antibody 2H5-A14 targeting a preS1 region of the HBV large envelope protein. We show that the A14 CAR T cell is capable of killing hepatocytes infected by HBV with high specificity; adoptive transfer of A14 CAR T cells to HBV infected humanized FRG mice resulted in reductions of all serum and intrahepatic virological markers to levels below the detection limit. A14 CAR T cells treatment increased the levels of human IFN-γ, GM-CSF, and IL-8/CXCL-8 in the mice. These results show that A14 CAR T cells may be further developed for curative therapy against HBV infection by eliminating HBV-infected hepatocytes and inducing production of pro-inflammatory and antiviral cytokines.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Inmunoterapia Adoptiva , Humanos , Animales , Ratones , Virus de la Hepatitis B/fisiología , Hepatitis B/terapia , Hígado/virología , Transducción Genética , Lentivirus/genética , Vectores Genéticos , Células T de Memoria/inmunología , Receptores Quiméricos de Antígenos/metabolismo , Inflamación/metabolismo , Citocinas/inmunología , Hepatocitos/virología
4.
J Virol ; 97(1): e0171722, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36475867

RESUMEN

Hepatitis B virus (HBV) infection remains a public health problem worldwide. Persistent HBV infection relies on active transcription of the covalently closed circular DNA (cccDNA) in hepatocytes, which is less understood at the single-cell level. In this study, we isolated primary human hepatocytes from liver-humanized FRG mice infected with HBV and examined cccDNA transcripts in single cells based on 5' end sequencing. Our 5' transcriptome sequencing (RNA-seq) analysis unambiguously assigns different viral transcripts with overlapping 3' sequences and quantitatively measures viral transcripts for structural genes (3.5 kb, 2.4 kb, and 2.1 kb) and the nonstructural X gene (0.7 kb and related) in single cells. We found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. Results from cell infection assays with recombinant HBV show that nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Moreover, upon HBV infection, cccDNA apparently can be transcribed in the absence of HBx and produces HBx, needed for productive transcription of other viral genes. These results shed new light on cccDNA transcription at the single-cell level and provide insights useful for improving the treatment strategy against chronic HBV infection. IMPORTANCE Hepatitis B virus (HBV) infection can be effectively suppressed but rarely cured by available drugs. Chronic HBV infection is based on persistence of covalently closed circular DNA (cccDNA) and continuous infection and reinfection with HBV in the liver. Understanding transcriptional regulation of cccDNA will help to achieve permanent transcriptional silencing, i.e., functional cure of HBV. In our study, we found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. The nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Upon an infection, cccDNA apparently can be transcribed in the absence of HBx to produce HBx, necessary for subsequent transcription of other HBV genes. Our studies shed new light on the mechanism of HBV infection and may have implications for a functional cure regimen for HBV.


Asunto(s)
ADN Circular , Hepatitis B Crónica , Sobreinfección , Animales , Humanos , Ratones , ADN Circular/genética , ADN Viral/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , Replicación Viral/genética , Hepatocitos , Proteínas Reguladoras y Accesorias Virales/genética
5.
Cell Rep ; 35(13): 109288, 2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34192543

RESUMEN

The hepatitis B virus (HBV) infects 257 million people worldwide. HBV infection requires establishment and persistence of covalently closed circular (ccc) DNA, a viral episome, in nucleus. Here, we study cccDNA spatial localization in the 3D host genome by using chromosome conformation capture-based sequencing analysis and fluorescence in situ hybridization (FISH). We show that transcriptionally inactive cccDNA is not randomly distributed in host nucleus. Rather, it is preferentially accumulated at specialized areas, including regions close to chromosome 19 (chr.19). Activation of the cccDNA is apparently associated with its re-localization, from a pre-established heterochromatin hub formed by 5 regions of chr.19 to transcriptionally active regions formed by chr.19 and nearby chromosomes including chr.16, 17, 20, and 22. This active versus inactive positioning at discrete regions of the host genome is primarily controlled by the viral HBx protein and by host factors including the structural maintenance of chromosomes protein 5/6 (SMC5/6) complex.


Asunto(s)
Cromosomas Humanos Par 19/genética , Genoma Humano , Virus de la Hepatitis B/genética , Hepatitis B/genética , Hepatitis B/virología , Plásmidos/genética , Transcripción Genética , Secuencia de Bases , Células Cultivadas , ADN Viral/genética , Genoma Viral , Células Hep G2 , Hepatocitos/patología , Hepatocitos/virología , Heterocromatina/metabolismo , Humanos
6.
Oncol Lett ; 21(4): 272, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33717269

RESUMEN

Cervical cancer is the second most common gynecological malignancy. Accumulating evidence has suggested that microRNAs (miRNAs) are involved in the occurrence and development of cervical cancer. The present study aimed to investigate the function and underlying molecular mechanism of microRNA (miRNA/miR)-29a in cervical cancer. Reverse transcription-quantitative PCR and methylation-specific PCR were used to examine the expression of miR-29a and methylated status of p16 promoter, respectively. Cell Counting Kit-8 analysis and flow cytometry were performed to evaluate cell viability and cycle, respectively. Dual-luciferase reporter assay was performed to verify the interaction between miR-29a and its targets. Western blot analysis was performed to detect the protein levels of DNA methyltransferases (DNMT)3A and DNMT3B. The results demonstrated that miR-29a expression was downregulated in cervical cancer tissues and cells, and negatively correlated with p16 promoter hypermethylation. Furthermore, cell experiments confirmed that miR-29a suppressed cell proliferation and induced cell cycle arrest in HeLa and C-33A cells. Mechanically, miR-29a restored normal methylation pattern of the p16 gene by sponging DNMT3A and DNMT3B. Taken together, the results of the present study demonstrated the epigenetic regulation of tumor suppressor p16 by miR-29a as a unique mechanism, thus providing a rationale for the development of miRNA-based strategies in the treatment of cervical cancer.

7.
Virology ; 522: 168-176, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30032030

RESUMEN

Sodium taurocholate cotransporting polypeptide (NTCP) is a functional receptor for human hepatitis B virus (HBV) and its satellite virus Hepatitis D virus (HDV). Physiologically, NTCP is responsible for the majority of sodium-dependent bile acids uptake by hepatocytes. The p.Ser267Phe (S267F) variant of NTCP is a single nucleotide polymorphism (SNP) previously found to cause substantial loss of ability to support HBV and HDV infection and its taurocholic acid uptake function in vitro. Intriguingly, ten individuals were identified as S267F homozygotes in population studies of chronic hepatitis B (CHB) patients. In this study, we identified new HBV isolates from one homozygous S267F mutation carrier and confirmed new isolates also use wildtype-NTCP as a cellular receptor. Furthermore, we demonstrated S267F variant of NTCP, though inefficient, is still a functional receptor for HBV entry. This study advances our understanding of NTCP-mediated HBV infection.


Asunto(s)
Virus de la Hepatitis B/crecimiento & desarrollo , Hepatitis B Crónica/virología , Interacciones Huésped-Patógeno , Proteínas Mutantes/metabolismo , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Receptores Virales/metabolismo , Simportadores/metabolismo , Línea Celular , Hepatitis B Crónica/genética , Hepatocitos/virología , Homocigoto , Humanos , Proteínas Mutantes/genética , Mutación Missense , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Receptores Virales/genética , Simportadores/genética , Internalización del Virus
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 10(5): 438-40, 2002 Oct.
Artículo en Chino | MEDLINE | ID: mdl-12513744

RESUMEN

In order to establish a new more rapid, safe and sensitive colorimetric assay for the proliferation of leukemic cells, MTS/pms has been developed. This automated colorimetric assay is based on the characteristic of viable and metabolically active leukemic cells to cleave MTS/pms into a water-soluble product whose optical density is determined at 492 nm by an automated microtiter-plate reader photometer. The results indicated that only active leukemic cells cleaved MTS/pms into product measured, and dead cells did not reduce MTS/pms. A linear relations hip were found between the viable cell number and optical density of MTS/pms cleaved by HL-60 and K562 cell (r = 0.963). Compared with MTT and INT assays, the reduced product of MTS/pms is water-soluble. It is concluded that MTS/pms colorimetric assay is more rapid, accurate and sensitive for the bioassay of proliferation of leukemic cells.


Asunto(s)
Colorimetría/métodos , Leucemia/patología , Metosulfato de Metilfenazonio/metabolismo , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , División Celular , Formazáns/metabolismo , Células HL-60 , Humanos , Células K562
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