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1.
Clin Chem Lab Med ; 62(1): 187-198, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-37531579

RESUMEN

OBJECTIVES: Epstein-Barr virus (EBV) C promoter (Cp) hypermethylation, a crucial factor for EBV latent infection of nasopharyngeal epithelial cells, has been recognized as a promising biomarker for nasopharyngeal carcinoma (NPC) detection. In this study, we develop a novel EBV Cp methylation quantification (E-CpMQ) assay and evaluate its diagnostic performance for NPC detection. METHODS: A novel qPCR assay for simultaneous quantification of methylated- and unmethylated EBV Cp was developed by the combinational modification of MethyLight and QASM, with an innovative calibrator to improve the detection accuracy and consistency. The NP swab samples and synthetic standards were used for the analytical validation of the E-CpMQ. The diagnostic efficacy of the developed E-CpMQ assay was validated in 137 NPC patients and 137 non-NPC controls. RESULTS: The E-CpMQ assay can detect the EBV Cp methylation ratio in one reaction system under 10 copies with 100 % recognition specificity, which is highly correlated to pyrosequencing with a correlation coefficient over 0.99. The calibrated E-CpMQ assay reduces the coefficient of variation by an average of 55.5 % with a total variance of less than 0.06 units standard deviation (SD). Linear methylation ratio detection range from 4.76 to 99.01 %. The sensitivity and specificity of the E-CpMQ respectively are 96.4 % (95 % CI: 91.7-98.8 %), 89.8 % (95 % CI: 83.5-94.3 %). CONCLUSIONS: The developed E-CpMQ assay with a calibrator enables accurate and reproducible EBV Cp methylation ratio quantification and offers a sensitive, specific, cost-effective method for NPC early detection.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/diagnóstico , Herpesvirus Humano 4/genética , Infecciones por Virus de Epstein-Barr/diagnóstico , Infecciones por Virus de Epstein-Barr/genética , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/genética , ADN Viral/genética , Nasofaringe , Metilación de ADN
2.
Appl Opt ; 62(21): 5778-5785, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37707196

RESUMEN

In this work, a hollow-core anti-resonant terahertz (THz) fiber with elliptical cladding and nested tubes is proposed and fabricated. It is an effective way to reduce the loss of THz waves by transmitting them in an air core and breaking the material absorption. After parameter optimization of the initial structure, multiple transmission windows exist in the 0.2-0.8 THz band, where confinement loss is as low as 3.47×10-3cm-1 at 0.8 THz. At 0.2-0.7 THz, confinement losses lie between 10-3 and 10-2cm-1. The 3D printed samples are characterized by a THz time-domain spectroscopy system. Experimental results showed that the designed fiber structure transmits loss coefficients up to 10-2cm-1 in the 0.2-0.8 THz band (the minimum value is located at 0.46 THz, corresponding to a loss coefficient of 0.0284cm-1). The experiments show that the designed THz fiber achieves a good transmission effect.

3.
Appl Opt ; 62(11): 2924-2935, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37133137

RESUMEN

We propose a machine-learning-based method for grating waveguides and augmented reality, significantly reducing the computation time compared with existing finite-element-based numerical simulation methods. Among the slanted, coated, interlayer, twin-pillar, U-shaped, and hybrid structure gratings, we exploit structural parameters such as grating slanted angle, grating depth, duty cycle, coating ratio, and interlayer thickness to construct the gratings. The multi-layer perceptron algorithm based on the Keras framework was used with a dataset comprised of 3000-14,000 samples. The training accuracy reached a coefficient of determination of more than 99.9% and an average absolute percentage error of 0.5%-2%. At the same time, the hybrid structure grating we built achieved a diffraction efficiency of 94.21% and a uniformity of 93.99%. This hybrid structure grating also achieved the best results in tolerance analysis. The high-efficiency artificial intelligence waveguide method proposed in this paper realizes the optimal design of a high-efficiency grating waveguide structure. It can provide theoretical guidance and technical reference for optical design based on artificial intelligence.

4.
Virus Res ; 331: 199117, 2023 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-37105437

RESUMEN

BACKGROUND: Hypertension may increase the infection risk of multiple viruses. The evidence for the association between hypertension and Epstein-Barr virus (EBV) reactivation is still largely lacking. METHODS: The study was based on the baseline information of a population-based prospective cohort from high-risk areas of nasopharyngeal carcinoma (NPC). Using two EBV reactivation classification criteria, we explored the relationship between hypertension and EBV reactivation through logistic regression models. RESULTS: We included a total of 12,159 subjects. Among them, 3,945 (32.45%) were EBV arbitrary seropositive, and 1,547 (12.72%) were EBV comprehensive seropositive. Hypertension was associated with an increased risk of EBV reactivation, with odds ratios (ORs) of 1.17 (95% CI = 1.08-1.27) for EBV arbitrary seropositive subjects and 1.16 (95% CI = 1.03-1.30) for EBV comprehensive seropositive subjects. Two types of antihypertensive drugs were associated with decreased risk of EBV reactivation: ß-adrenergic receptor-blocking agents (ß-blockers) (OR = 0.51, 95% CI = 0.42-0.61 for EBV arbitrary seropositive subjects; OR = 0.62, 95% CI = 0.47-0.81 for EBV comprehensive seropositive subjects) and angiotensin converting enzyme inhibitors (ACEIs) (OR = 0.61, 95% CI = 0.41-0.88 for EBV arbitrary seropositive subjects; OR = 0.58, 95% CI = 0.32-0.98 for EBV comprehensive seropositive subjects). CONCLUSIONS: Hypertension was associated with an increased risk of EBV reactivation in high-incidence areas of NPC. ß-blockers and ACEIs reduce this risk, and thus might be used for NPC prevention in endemic areas.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Hipertensión , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/complicaciones , Carcinoma Nasofaríngeo/epidemiología , Herpesvirus Humano 4/fisiología , Neoplasias Nasofaríngeas/complicaciones , Estudios Prospectivos , Hipertensión/complicaciones
5.
J Clin Lab Anal ; 35(9): e23962, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34399000

RESUMEN

BACKGROUND: Liquid biopsy is gaining increasing popularity in cancer screening and diagnosis. However, there is no relatively mature DNA isolation method or commercial kit available that is compatible with different LB sample types. This study developed a PAN-sample DNA isolation method (PAN method) for liquid biopsy samples. METHODS: The PAN method has two key steps, including biosample-specific pretreatments for various LB sample types and high concentration guanidine thiocyanate buffer for lysis and denaturation procedure. Subsequently, the performance of PAN method was validated by a series of molecular analyses. RESULTS: The PAN method was used to isolate DNA from multiple sample types related to LB, including plasma, serum, saliva, nasopharyngeal swab, and stool. All purified DNA products showed good quality and high quantity. Comparison of KRAS mutation analysis using DNA purified using PAN method versus QIAamp methods showed similar efficiency. Epstein-Barr virus DNA was detected via Q-PCR using DNA purified from serum, plasma, nasopharyngeal swab, and saliva samples collected from nasopharyngeal carcinoma patients. Similarly, methylation sequencing of swab and saliva samples revealed good coverage of target region and high methylation of HLA-DPB1 gene. Finally, 16S rDNA gene sequencing of saliva, swab, and stool samples successfully defines the relative abundance of microbial communities. CONCLUSIONS: This study developed and validated a PAN-sample DNA isolation method that can be used for different LB samples, which can be applied to molecular epidemiological research and other areas.


Asunto(s)
ADN Viral/aislamiento & purificación , Infecciones por Virus de Epstein-Barr/diagnóstico , Heces/virología , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/diagnóstico , Saliva/virología , Manejo de Especímenes/métodos , Estudios de Casos y Controles , Metilación de ADN , ADN Viral/análisis , ADN Viral/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/virología , Cadenas beta de HLA-DP/análisis , Cadenas beta de HLA-DP/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Biopsia Líquida , Neoplasias Nasofaríngeas/virología , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S
6.
BMC Cancer ; 21(1): 651, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34074258

RESUMEN

OBJECTIVE: Plasma Epstein-Barr virus (EBV) DNA is considered a biomarker for nasopharyngeal carcinoma (NPC). However, its long-term role in NPC development is unclear. MATERIALS AND METHODS: A total of 1363 participants seropositive for EBV VCA-IgA and EBNA1-IgA in a community-based NPC screening program in southern China were tested for plasma EBV DNA levels by real-time qPCR between 2008 and 2015. New NPC cases were confirmed by active follow-up approach and linkage to local cancer registry through the end of 2016. Cox proportional hazards regression analysis was performed to calculate the hazard ratios (HRs) for NPC risk with plasma EBV DNA. RESULTS: Thirty patients were newly diagnosed during a median 7.5 years follow-up. NPC incidence increased with the plasma EBV DNA load ranging from 281.46 to 10,074.47 per 100,000 person-years in participants with undetectable and ≥ 1000 copies/ml levels; the corresponding cumulative incidence rates were 1.73 and 50%. Furthermore, plasma EBV DNA loads conferred an independent risk for NPC development after adjustment for other risk factors, with HRs of 7.63 for > 3-999 copies/ml and 39.79 for ≥1000 copies/ml. However, the HRs decreased gradually after excluding NPC cases detected in the first 2 to 3 years and became statistically nonsignificant by excluding cases detected during the first 4 years. CONCLUSION: Elevated plasma EBV DNA can predict NPC risk over 3 years. Monitoring plasma EBV DNA can be used as a complementary approach to EBV serological antibody-based screening for NPC.


Asunto(s)
Biomarcadores de Tumor/sangre , ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/epidemiología , Carcinoma Nasofaríngeo/epidemiología , Neoplasias Nasofaríngeas/epidemiología , Adulto , Anciano , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/diagnóstico , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/sangre , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/virología , Neoplasias Nasofaríngeas/sangre , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/virología , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Pruebas Serológicas/estadística & datos numéricos
7.
Langmuir ; 30(14): 3949-56, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24650361

RESUMEN

A new monitoring technique, which combines real-time in-situ CCD camera observation and reflectance spectra measurement, has been developed to study the growing and drying processes of evaporation-induced self-assembly (EISA). Evolutions of the reflectance spectrum and CCD camera images both reveal that the entire process of polystyrene (PS) EISA contains three stages: crack-initiation stage (T1), crack-propagation stage (T2), and crack-remained stage (T3). A new phenomenon, the red-shift of stop-band, is observed when the crack begins to propagate in the monitored window of CCD camera. Deformation of colloidal spheres, which mainly results in the increase of volume fraction of spheres, is applied to explain the phenomenon. Moreover, the modified scalar wave approximation (SWA) is utilized to analyze the reflectance spectra, and the fitting results are in good agreement with the evolution of CCD camera images. This new monitoring technique and the analysis method provide a good way to get insight into the growing and drying processes of PS colloidal self-assembly, especially the crack propagation.

8.
J Chem Phys ; 137(23): 234111, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23267475

RESUMEN

Self-assembled photonic structures have been under theoretical and experimental study for decades, whereas previous theories on optical properties were mainly concerned with perfect structure or some certain limited kinds of disordered photonic crystals (PCs), making them unsuitable for characterizing the real self-assembled PCs. In order to improve our understanding of the mechanism of self-assembly and provide more crucial clues to further grow perfect crystals, we extended previous widely used scalar wave approximation (SWA), making it be able to characterize long-range disorder (ß) and short-range disorder (α) in PCs synthetically in a simple and effective way. Excellent agreement with in situ observed reflectance of evaporation induced self-assembled colloidal photonic crystals (CPCs) was obtained, demonstrating that the introduction of the parameters α and ß in SWA can successfully characterize the disorder in self-assembled CPCs. Furthermore, extended SWA was further used to study the disorder formation in self-assembly, and it was found that during growing stage both ß and α drop down, whereas in drying stage ß stays nearly unchanged while α increases significantly. It turned out that the growing stage of self-assembly is a stage when the structure transforms from disordered to ordered one, and growth induced disorder mainly arises in drying stage. The results obtained provide an insight into the growth mechanisms of self-assembly and theoretical basis for characterizing optical properties of disordered PCs.

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