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1.
Mol Carcinog ; 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39352309

RESUMEN

The reverse transcriptase subunit of telomerase, TERT, is frequently activated in high-grade dysplasia and invasive cancers of the uterine cervix. Telomerase activation through hypomethylation of the TERT promoter holds promise as a biomarker for cervical cancer progression, however, specific CpG sites involved in cervical cancer risk remain to be fully defined. A recent genome-wide association study on cervical cancer identified genetic polymorphisms at 5p13.33 (close to TERT-CLPTM1L) but the underlying mechanisms are undetermined. We investigated 529 CpG sites within the TERT promoter region and 3 CpG islands nearby, and 21 CpG sites within CLPTM1L in 190 bisulfite-converted cervical tumor DNA samples from BioRAIDs (NCT02428842). We identified eight CpG sites within TERT intron 2 where methylation was significantly associated with the genotypes of cervical cancer risk variants rs27070 and rs459961 in cervical tumors after multiple testing correction (p < 9.4 × 10E-5). Hypermethylation at chr5:1289663 correlated with decreased TERT mRNA levels. In an independent series of 188 normal or dysplastic cervical tissues, rare alleles of rs27070 and rs459961 were associated with low basal CLPTM1L levels and with the absence of TERT mRNA in HPV-negative samples, consistent with their proposed role as protective variants for cervical cancer. HPV infection was associated with increased CLPTM1L and TERT levels. Collectively, our results provide a link between cervical cancer risk variants, methylation, and gene expression and implicate both TERT and CLPTM1L as genes modulated by genomic background and HPV infection during cervical cancer development.

2.
BMC Pregnancy Childbirth ; 23(1): 392, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37245038

RESUMEN

BACKGROUND: Antiviral intervention in hepatitis B virus (HBV)-infected pregnant women can effectively reduce mother-to-child transmission. However, the immunological characteristics of pregnant women with chronic HBV infection and the effects of antiviral intervention during pregnancy on maternal immune response remain unknown. We aimed to investigate these effects by comparing mothers who received antiviral intervention during pregnancy with those who did not. METHODS: Pregnant women positive for hepatitis B surface antigen and hepatitis B e-antigen (HBsAg+ HBeAg+) were enrolled at delivery, including 34 received prophylactic antiviral intervention during pregnancy (AVI mothers) and 15 did not (NAVI mothers). T lymphocyte phenotypes and functions were analysed using flow cytometry. RESULTS: At delivery, maternal regulatory T cell (Treg) frequency in AVI mothers was significantly higher than that in NAVI mothers (P < 0.002), and CD4+ T cells in AVI mothers displayed a decreased ability to secrete IFN-γ (P = 0.005) and IL-21 (P = 0.043), but an increased ability to secrete IL-10 and IL-4 (P = 0.040 and P = 0.036), which represented a higher Treg frequency, enhanced Th2 response and suppressed Th1 response. Treg frequency among AVI mothers was correlated negatively with serum HBsAg and HBeAg levels. After delivery, the ability of CD4+ T cells or CD8+ T cells to secrete IFN-γ or IL-10 was similar and no significant difference in Treg frequency was found between the two groups. CONCLUSIONS: Prophylactic antiviral intervention during pregnancy has an effect on T cell immunity in pregnant women, which was characterised by increased maternal Treg frequency, enhanced Th2 response and suppressed Th1 response at delivery.


Asunto(s)
Hepatitis B , Complicaciones Infecciosas del Embarazo , Femenino , Embarazo , Humanos , Virus de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Antivirales/uso terapéutico , Antígenos e de la Hepatitis B , Interleucina-10/uso terapéutico , Mujeres Embarazadas , Linfocitos T CD8-positivos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Hepatitis B/prevención & control , ADN Viral
3.
Opt Express ; 29(17): 26332-26339, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34615070

RESUMEN

We demonstrate an L-band wavelength-tunable passively mode-locked fiber laser using a single long-period fiber grating (LPFG) as a narrow-band optical attenuator (NBOA). Through bending the LPFG, the central wavelength can be continuously tuned from 1582.02 to 1597.29 nm, while the output power only varies from 1.465 to 1.057 mW, approximately a rate of 22 µW/nm variation. This is the first time that LPFG is functioned as a NBOA in mode-locked fiber lasers, showing the great advantage of less impact on output power variation reduction. Besides, the total cavity length is 5.08 m, which is the shortest length yet reported in wavelength-tunable mode-locked fiber lasers. The wavelength tuning could also be realized at harmonic mode locking with tuning range of 14.69 nm under 5th harmonic.

4.
Scand J Immunol ; 92(2): e12914, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32533709

RESUMEN

Immature immune system and immune tolerance induced by exposure to HBeAg in utero and/or shortly after infection in newborns were reportedly the causes of chronic HBV infection. To investigate the effect of maternal-derived HBeAg on neonatal T cell immunity, we analysed and compared T cell phenotypes and functions among neonates born to HBsAg+ /HBeAg+ mothers (HBeAg+ neonates), HBsAg+ /HBeAg- mothers (HBeAg- neonates) and healthy control mothers (HC neonates), using flow cytometry. The results showed that neonatal T cell phenotypes were similar regardless of HBeAg exposure. Upon anti-CD3 and anti-CD28 stimulation in HBeAg+ neonates, CD4+ T cell production of IFN-γ (P < .05) was significantly enhanced, while CD8+ T cells secreted significantly more IL-2 compared with those in HBeAg- and HC groups (P < .05). Moreover, similar levels of IFN-γ and IL-10 were observed in the culture supernatant after stimulation with rHBsAg, rHBcAg or rHBeAg among HBeAg+ , HBeAg- and HC neonates, whereas HBeAg+ neonates produced more TNF-α than HBeAg- neonates upon stimulation with rHBcAg. In conclusion, the results indicated that the HBsAg+ /HBeAg+ maternal environment did not influence the phenotypes of cord blood T cells but boosted neonatal non-specific Th1-type cytokine production.


Asunto(s)
Sangre Fetal/inmunología , Antígenos e de la Hepatitis B/inmunología , Complicaciones Infecciosas del Embarazo/inmunología , Efectos Tardíos de la Exposición Prenatal/inmunología , Linfocitos T/inmunología , Citocinas/inmunología , Femenino , Hepatitis B/inmunología , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo
5.
Haematologica ; 104(10): 1984-1994, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30819915

RESUMEN

Transmembrane protein 30A (Tmem30a) is the ß-subunit of P4-ATPases which function as flippase that transports aminophospholipids such as phosphatidylserine from the outer to the inner leaflets of the plasma membrane to maintain asymmetric distribution of phospholipids. It has been documented that deficiency of Tmem30a led to exposure of phosphatidylserine. However, the role of Tmem30a in vivo remains largely unknown. Here we found that Vav-Cre-driven conditional deletion of Tmem30a in hematopoietic cells led to embryonic lethality due to severe anemia by embryonic day 16.5. The numbers of erythroid colonies and erythroid cells were decreased in the Tmem30a deficient fetal liver. This was accompanied by increased apoptosis of erythroid cells. Confocal microscopy analysis revealed an increase of localization of erythropoietin receptor to areas of membrane raft microdomains in response to erythropoietin stimulation in Ter119-erythroid progenitors, which was impaired in Tmem30a deficient cells. Moreover, erythropoietin receptor (EPOR)-mediated activation of the STAT5 pathway was significantly reduced in Tmem30a deficient fetal liver cells. Consistently, knockdown of TMEM30A in human CD34+ cells also impaired erythropoiesis. Our findings demonstrate that Tmem30a plays a critical role in erythropoiesis by regulating the EPOR signaling pathway through the formation of membrane rafts in erythroid cells.


Asunto(s)
Eritropoyesis , Feto/embriología , Hematopoyesis Extramedular , Células Madre Hematopoyéticas/enzimología , Hígado/embriología , Proteínas de la Membrana/deficiencia , Animales , Feto/citología , Células Madre Hematopoyéticas/citología , Hígado/citología , Microdominios de Membrana/enzimología , Microdominios de Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Transducción de Señal
6.
Stat Med ; 37(7): 1162-1177, 2018 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-29250813

RESUMEN

The Cox proportional hazards (PH) model is a common statistical technique used for analyzing time-to-event data. The assumption of PH, however, is not always appropriate in real applications. In cases where the assumption is not tenable, threshold regression (TR) and other survival methods, which do not require the PH assumption, are available and widely used. These alternative methods generally assume that the study data constitute simple random samples. In particular, TR has not been studied in the setting of complex surveys that involve (1) differential selection probabilities of study subjects and (2) intracluster correlations induced by multistage cluster sampling. In this paper, we extend TR procedures to account for complex sampling designs. The pseudo-maximum likelihood estimation technique is applied to estimate the TR model parameters. Computationally efficient Taylor linearization variance estimators that consider both the intracluster correlation and the differential selection probabilities are developed. The proposed methods are evaluated by using simulation experiments with various complex designs and illustrated empirically by using mortality-linked Third National Health and Nutrition Examination Survey Phase II genetic data.


Asunto(s)
Funciones de Verosimilitud , Análisis de Regresión , Análisis por Conglomerados , Simulación por Computador , Bases de Datos Genéticas , Humanos , Mortalidad , Análisis Multivariante , Encuestas Nutricionales , Análisis de Supervivencia
7.
Biometrics ; 72(2): 546-53, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26583951

RESUMEN

In this article, we develop a piecewise Poisson regression method to analyze survival data from complex sample surveys involving cluster-correlated, differential selection probabilities, and longitudinal responses, to conveniently draw inference on absolute risks in time intervals that are prespecified by investigators. Extensive simulations evaluate the developed methods with extensions to multiple covariates under various complex sample designs, including stratified sampling, sampling with selection probability proportional to a measure of size (PPS), and a multi-stage cluster sampling. We applied our methods to a study of mortality in men diagnosed with prostate cancer in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial to investigate whether a biomarker available from biospecimens collected near time of diagnosis stratifies subsequent risk of death. Poisson regression coefficients and absolute risks of mortality (and the corresponding 95% confidence intervals) for prespecified age intervals by biomarker levels are estimated. We conclude with a brief discussion of the motivation, methods, and findings of the study.


Asunto(s)
Interpretación Estadística de Datos , Análisis de Supervivencia , Factores de Edad , Ensayos Clínicos como Asunto , Análisis por Conglomerados , Humanos , Masculino , Modelos Estadísticos , Distribución de Poisson , Neoplasias de la Próstata/mortalidad , Análisis de Regresión , Riesgo , Medición de Riesgo/estadística & datos numéricos , Tamaño de la Muestra
8.
Alpha Psychiatry ; 25(2): 233-242, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38798807

RESUMEN

Objective: This survey investigated the prevalence, distribution, and correlative factors of insomnia symptoms among people aged 65 and above in Guangdong Province, China. Methods: The Guangdong Mental Health Survey was conducted on the elderly in all 21 cities of Guangdong Province from September to December 2021. Multistage stratified cluster sampling was adopted, and 16 377 adult residents were interviewed face-to-face, from which 4001 elderly participants aged 65 and above were included for this study. Complex weighted adjustment methods were applied to weight the data. Multinomial logistic regression was applied to test the independent associations of clinical insomnia symptoms (CIS) and subthreshold insomnia symptoms (SIS) with the factors. Results: The pooled estimate of insomnia symptoms was 13.44% [95% confidence interval (CI): 12.2 %-14.7%]. The 1-month weighted prevalence of SIS and CIS were 11.15% (95% CI: 10.05%-12.37%) and 2.28% (95%CI: 1.77%-2.94%), respectively. Multinomial logistic regression analysis revealed that urban residence, irregular diet, low body mass index, chronic disease, napping 3-4/week, early changes in dementia, symptoms of subthreshold depression, subthreshold generalized anxiety, and generalized anxiety disorder were positively associated with SIS. Additionally, living in urban areas, having chronic diseases, symptoms of subthreshold depression, major depressive disorder, subthreshold generalized anxiety, generalized anxiety disorder were positively associated with CIS. Conclusion: Insomnia symptoms, including CIS and SIS, were prevalent among the elderly in Guangdong Province. Given the high burden of CIS and SIS, policymakers and healthcare professionals must explore and treat the related factors accordingly.

9.
J Chromatogr A ; 1710: 464379, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37778099

RESUMEN

Based on one-step vortex extraction and purification combined with gas chromatography-tandem mass spectrometry (GC-MS/MS), we established a simple, rapid, and efficient method for the simultaneous determination of four skin penetration enhancers in cosmetics, including isosorbide dimethyl ether, isopropyl myristate, N-butylsaccharin and Azone. The extraction procedure was performed in a centrifuge tube, allowing extraction and purification in a single step. The cosmetic sample was extracted by n-hexane-ethyl acetate (1:1, V/V), purified by silica gel and anhydrous magnesium sulfate as the solid phase purification agent, separated on a TG-5 ms column (30.0 m × 0.25 mm × 0.25 µ m), confirmed and detected by GC-MS/MS in the selected reaction monitoring (SRM) mode, and quantified by the internal standard method with Di-n­butyl phthalate-D4(DBP-D4) as the internal standard. The selections of a column, extraction solvent, and solid phase purification agent were optimized. Under the optimized conditions, the four skin penetration enhancers showed good linearities in the range of 0.02∼0.50 mg L - 1. The correlation coefficients (r) were 0.992 ∼ 0.997, exceeding the specifications requirements (r ≥ 0.990); The detection (LODs, S/N = 3) and quantification limits (LOQs, S/N = 10) of the method were 0.08 ∼ 0.12 mg kg-1 and 0.25 ∼ 0.40 mg kg-1, respectively. According to the cosmetic matrix in different formulation systems, the spiked recovery tests were carried out at three levels, i.e., low, medium, and high. The average recoveries of the analytes were 85.3% ∼ 95.6%, and the relative standard deviations (RSDs, n = 6) were 2.1% ∼ 7.8%. The established method was also employed to analyze cosmetics in the market. Azone, isosorbide dimethyl ether, and isopropyl myristate resulted as the most widely used skin penetration enhancers in cosmetics. The method established in this study has the advantages of operational simplicity, high sensitivity, good reproducibility, and low consumption of samples and solvents. Moreover, it can be used to determine skin penetration enhancers in cosmetics.


Asunto(s)
Cosméticos , Espectrometría de Masas en Tándem , Cromatografía de Gases y Espectrometría de Masas , Reproducibilidad de los Resultados , Cosméticos/química , Isosorbida/análisis , Extracción en Fase Sólida , Cromatografía Líquida de Alta Presión
10.
Front Public Health ; 11: 1030456, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36960374

RESUMEN

Background: Emergency medical service personnel are subjected to various stressors, which makes them more likely to develop post-traumatic stress disorder symptoms. Studies have shown that psychological detachment and presenteeism play a role at the level of post-traumatic stress disorder. There is no study to examine the relationship between psychological detachment, presenteeism, and post-traumatic stress disorder among emergency medical service personnel. Objective: The main objective of the study is to investigate the effects of presenteeism in explaining the relationship between psychological detachment and post-traumatic stress disorder among emergency medical service personnel. Design: A cross-sectional study was conducted among 836 emergency medical service personnel in 51 counties and cities in Hunan Province, China. Methods: They were anonymously investigated by using the Impact of Event Scale-Revised (IES-R), the Stanford Presenteeism scale-6 (SPS-6), and the Psychological Detachment Scale. Statistic description, univariate analysis, pearson correlation, and structural equation model were adopted to analyze the data. Results: The mean score of IES-R, SPS-6, and the psychological detachment scale were 22.44 ± 16.70, 15.13 ± 4.20, and 11.30 ± 4.24. Post-traumatic stress disorder was positively relevant with presenteeism (r = 0.381, p< 0.01), but negatively correlated with psychological detachment (r = -0.220, p < 0.01). And presenteeism partially mediated the association between psychological detachment and post-traumatic stress disorder. Conclusions: The results show a high prevalence of post-traumatic stress disorder symptoms in EMS personnel, presenteeism can statistically significantly predict post-traumatic stress disorder symptoms. If hospital management can reduce the presenteeism of emergency medical service personnel, this will help them reduce post-traumatic stress disorder symptoms.


Asunto(s)
Servicios Médicos de Urgencia , Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/epidemiología , Presentismo , Estudios Transversales , Encuestas y Cuestionarios
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