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1.
Brief Bioinform ; 24(4)2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37193672

RESUMEN

The rational design of chemical entities with desired properties for a specific target is a long-standing challenge in drug design. Generative neural networks have emerged as a powerful approach to sample novel molecules with specific properties, termed as inverse drug design. However, generating molecules with biological activity against certain targets and predefined drug properties still remains challenging. Here, we propose a conditional molecular generation net (CMGN), the backbone of which is a bidirectional and autoregressive transformer. CMGN applies large-scale pretraining for molecular understanding and navigates the chemical space for specified targets by fine-tuning with corresponding datasets. Additionally, fragments and properties were trained to recover molecules to learn the structure-properties relationships. Our model crisscrosses the chemical space for specific targets and properties that control fragment-growth processes. Case studies demonstrated the advantages and utility of our model in fragment-to-lead processes and multi-objective lead optimization. The results presented in this paper illustrate that CMGN has the potential to accelerate the drug discovery process.


Asunto(s)
Diseño de Fármacos , Descubrimiento de Drogas , Aprendizaje , Redes Neurales de la Computación , Proteínas Tirosina Quinasas Receptoras
2.
J Biol Chem ; 299(9): 105082, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37495108

RESUMEN

The development and progression of nasopharyngeal carcinoma (NPC) is closely associated with Epstein-Barr virus (EBV) infection. NPC is usually asymptomatic until it spreads to other sites, and more than 70% of cases are classified as locally advanced disease at diagnosis. EBV-positive nasopharyngeal cancer tissues express only limited viral latent proteins, but express high levels of the EBV-encoded BamHI-A rightward transcript (BART) miRNA molecules. Here, we report that EBV-miRNA-BART2-5p (BART2-5p) promotes NPC cell invasion and metastasis in vivo and in vitro but has no effect on NPC cell proliferation and apoptosis. In addition, BART2-5p altered the mRNA and miRNA expression profiles of NPC cells. The development of human tumors has been reported to be associated with altered miRNAs expression, and overall miRNAs expression is reduced in many types of tumors. We found that BART2-5p downregulated the expression of several miRNAs that could exert oncogenic functions. Mechanistically, BART2-5p directly targets the RNase III endonuclease DICER1, inhibiting its function of cleaving double-stranded stem-loop RNA into short double-stranded RNA, which in turn causes altered expression of a series of key epithelial-mesenchymal transition molecules, and reverting DICER1 expression can rescue this phenotype. Furthermore, analysis from clinical samples showed a negative correlation between BART2-5p and DICER1 expression. According to our study, high expression of BART2-5p in tissues and plasma of patients with NPC is associated with poor prognosis. Our results suggest that, BART2-5p can accelerate NPC metastasis through modulating miRNA profiles which are mediated by DICER1, implying a novel role of EBV miRNAs in the pathogenesis of NPC.


Asunto(s)
Infecciones por Virus de Epstein-Barr , MicroARNs , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Ribonucleasa III , Humanos , Infecciones por Virus de Epstein-Barr/enzimología , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/genética , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Ribonucleasa III/genética , Ribonucleasa III/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/genética , Movimiento Celular/genética
3.
Biostatistics ; 24(2): 372-387, 2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33880509

RESUMEN

Studies of memory trajectories using longitudinal data often result in highly nonrepresentative samples due to selective study enrollment and attrition. An additional bias comes from practice effects that result in improved or maintained performance due to familiarity with test content or context. These challenges may bias study findings and severely distort the ability to generalize to the target population. In this study, we propose an approach for estimating the finite population mean of a longitudinal outcome conditioning on being alive at a specific time point. We develop a flexible Bayesian semiparametric predictive estimator for population inference when longitudinal auxiliary information is known for the target population. We evaluate the sensitivity of the results to untestable assumptions and further compare our approach to other methods used for population inference in a simulation study. The proposed approach is motivated by 15-year longitudinal data from the Betula longitudinal cohort study. We apply our approach to estimate lifespan trajectories in episodic memory, with the aim to generalize findings to a target population.


Asunto(s)
Modelos Estadísticos , Humanos , Estudios Longitudinales , Teorema de Bayes , Estudios de Cohortes , Simulación por Computador
4.
J Virol ; 97(9): e0088123, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37681959

RESUMEN

Epstein-Barr virus (EBV)-encoded miRNAs within the BamHI-A rightward transcript (BART) region are abundantly expressed in EBV-associated gastric cancer (EBVaGC), suggesting that they play roles in tumorigenesis. However, how these viral miRNAs contribute to the development of EBVaGC remains largely obscure. In this study, we found that EBV-encoded miR-BART11-3p targets 3' -UTR of dual-specificity phosphatase 6 (DUSP6) mRNA to upregulate ERK phosphorylation and downregulate JNK and p38 phosphorylation. By doing so, miR-BART11-3p promotes gastric cancer (GC) cell proliferation, migration, and invasion in vitro, and facilitates tumor growth in vivo. Restoration of DUSP6 expression reverses the tumor-promoting activity of miR-BART11-3p in AGS GC cells. Consistently, knockdown of DUSP6 ablates the antitumor effects of miR-BART11-3p inhibitors in EBV-positive GC cells. Furthermore, blocking ERK phosphorylation with trametinib inhibited the proliferation, migration, and invasion of miR-BART11-3p-expressing AGS cells. Administration of a miR-BART11-3p antagomir reduced the growth of EBV-positive xenograft tumors. Together, these findings reveal a novel mechanism by which EBV dysregulates MAPK pathways through an EBV-encoded microRNA to promote the development and progression of EBVaGC, which may be harnessed to develop new therapeutics to treat EBVaGC. IMPORTANCE The Epstein-Barr virus (EBV) is the first human tumor virus found to encode miRNAs, which within the BART region have been detected abundantly in EBV-associated gastric cancer (EBVaGC) and play various roles in promoting tumorigenesis. In our study, we observed that EBV-miR-BART11-3p promotes cell proliferation and induces migration and invasion in GC. Interestingly, we showed that miR-BART11-3p upregulates p-ERK and downregulates p-JNK and p-p38 by directly targeting 3'-UTR of dual-specificity phosphatase 6 (DUSP6). Restoration of DUSP6 rescues the effects generated by miR-BART11-3p in GC cells, and blocking ERK phosphorylation with Trametinib augments JNK and p38 phosphorylation and inhibits the effects of miR-BART11-3p-expressing AGS cells, suggesting that miR-BART11-3p promotes cell proliferation, migration, and invasion by modulating DUSP6-MAPK axis in EBVaGC. The findings presented in this study provide new mechanisms into the tumorigenesis in EBVaGC and new avenues for the development of therapeutic strategies to combat EBVaGC targeting miR-BART11-3p or phospho-ERK.

5.
Psychophysiology ; : e14660, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090795

RESUMEN

Understanding the subprocesses of risky decision making is a prerequisite for understanding (dys-)functional decisions. For the present fMRI study, we designed a novel variant of the balloon-analog-risk task (BART) that measures three phases: decision making, reward anticipation, and feedback processing. Twenty-nine healthy young adults completed the BART. We analyzed neural activity and functional connectivity. Parametric modulation allowed assessing changes in brain functioning depending on the riskiness of the decision. Our results confirm involvement of nucleus accumbens, insula, anterior cingulate cortex, and dorsolateral prefrontal cortex in all subprocesses of risky decision-making. In addition, subprocesses were differentiated by the strength of activation in these regions, as well as by changes in activity and nucleus accumbens-connectivity by the riskiness of the decision. The presented fMRI-BART variant allows distinguishing activity and connectivity during the subprocesses of risky decision making and shows how activation and connectivity patterns relate to the riskiness of the decision. Hence, it is a useful tool for unraveling impairments in subprocesses of risky decision making in people with high risk behavior.

6.
Virus Genes ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096336

RESUMEN

Epstein-Barr virus (EBV) is the first human oncogenic virus known to express microRNAs (miRNAs), which are closely associated with the development of various tumors, including nasopharyngeal and gastric cancers. Stearoyl-CoA Desaturase 1 (SCD1) is a key enzyme in fatty acid synthesis, highly expressed in numerous tumors, promoting tumor growth and metastasis, making it a potential therapeutic target. In this study, we found that SCD1 expression in EBV-associated gastric cancer (EBVaGC) was significantly lower than in EBV-negative gastric cancer (EBVnGC) at both cellular and tissue levels. In addition, EBV-miR-BART20-5p targets the 3'-UTR of SCD1, downregulating its expression. Moreover, overexpression of SCD1 in EBVaGC cells promoted cell migration and proliferation while inhibiting autophagy. These results suggest that EBV-encoded miRNA-BART20-5p may contribute to EBVaGC progression by targeting SCD1.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38706423

RESUMEN

OBJECTIVE: Hemoglobin (Hb) Bart's disease is a severe manifestation of alpha thalassemia, resulting in fetal tissue hypoxia and severe anemia. There is limited research available on assessing fetal speckle tracking analysis as a response to fetal anemia caused by Hb Bart's disease and its utility as a sonographic predictor for Hb Bart's disease. This study aimed to assess the diagnostic performance of fetal cardiac parameters derived from speckle tracking echocardiography for distinguishing between affected and unaffected fetuses in pregnancies at risk of Hb Bart's disease during the 17-24 gestational weeks. METHODS: A total of 115 pregnant women at risk for fetal Hb Bart's disease, who underwent either amniocentesis or cordocentesis at Siriraj Hospital, Bangkok Thailand, were included. Speckle tracking analysis was performed on the 4-chamber view (4CV) of the fetal heart, assessing heart size, shape, ventricular contractility, and left ventricular function prior to invasive prenatal testing. Logistic regression analysis determined significant cardiac predictors and calculated the probability of a fetus having Hb Bart's disease. RESULTS: Among the cohort, 38 fetuses (33%) were diagnosed with Hb Bart's disease, and 9 cases (7.8%) exhibited frank hydropic signs. In comparison to the control group, affected fetuses displayed a notable enlargement of the 4CV and a more globular shape specifically in the right ventricular chamber. Additionally, there were significant differences in the left global and longitudinal contractility between affected and unaffected fetuses. However, at mid-gestation, no significant distinctions were observed in terms of transverse contractility and left ventricular function between the two groups. Based on logistic regression analysis, combined cardiac parameters derived from speckle tracking analysis as a function of head circumference, could differentiate non-hydropic fetuses with Hb Bart's disease from unaffected fetuses, achieving a maximum sensitivity of 100%, specificity of 98.7%, and overall accuracy of 99.06%. CONCLUSIONS: Speckle tracking echocardiography has the potential to accurately identify early fetal heart changes in individuals at risk of developing Bart's anemia during the second trimester. This not only offers a novel predictive marker for Hb Bart's disease but also helps address the question of the underlying mechanisms of heart failure associated with anemia. This article is protected by copyright. All rights reserved.

8.
BMC Pregnancy Childbirth ; 24(1): 141, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365664

RESUMEN

OBJECTIVE: Whether or not the effects of anemia in the early phase, while the fetuses attempts to increase cardiac output to meet oxygen requirement in peripheral organs, is detrimental to the fetal developing vital organs is little-known. The objective of this is to compare prenatal cardiovascular changes and post-abortal cellular damages in the myocardium as a pumping organ and the brain as a perfused organ between anemic fetuses (using fetal Hb Bart's disease as a study model) in pre-hydropic phase and non-anemic fetuses. METHODS: Fetuses affected by Hb Bart's disease and non-anemic fetuses at 16-22 weeks were recruited to undergo comprehensive fetal echocardiography. Cord blood analysis was used to confirm the definite diagnosis of fetal Hb Bart's disease and normal fetuses. Fetal cardiac and brain tissues were collected shortly after pregnancy termination for the determination of oxidative stress and mitochondrial function, including mitochondrial ROS production and mitochondrial membrane changes. RESULTS: A total of 18 fetuses affected by Hb Bart's disease and 13 non-anemic fetuses were recruited. The clinical characteristics of both groups were comparable. The affected fetuses showed a significant increase in cardiac dimensions, cardiac function, cardiac output and brain circulation without deteriorating cardiac contractility and preload. However, in the affected fetuses, mitochondrial dysfunction was clearly demonstrated in brain tissues and in the myocardium, as indicated by a significant increase in the membrane potential change (p-value < 0.001), and a significant increase in ROS production in brain tissues, with a trend to increase in myocardium. The findings indicated cellular damage in spite of good clinical compensation. CONCLUSION: The new insight is that, in response to fetal anemia, fetal heart increases in size (dilatation) and function to increase cardiac output and blood flow velocity to provide adequate tissue perfusion, especially brain circulation. However, the myocardium and brain showed a significant increase in mitochondrial dysfunction, suggesting cellular damage secondary to anemic hypoxia. The compensatory increase in circulation could not completely prevent subtle brain and heart damage.


Asunto(s)
Anemia , Enfermedades Fetales , Hemoglobinas Anormales , Enfermedades Mitocondriales , Talasemia alfa , Femenino , Embarazo , Humanos , Segundo Trimestre del Embarazo , Especies Reactivas de Oxígeno , Hemoglobinas Anormales/análisis , Enfermedades Fetales/diagnóstico , Corazón Fetal/diagnóstico por imagen , Miocardio/química , Edema , Gasto Cardíaco
9.
Biochem Genet ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467887

RESUMEN

Nasopharyngeal carcinoma (NPC) is one of the most common tumors of head and neck in the Southeast Asia. PD-L1-dependent immune escape plays a critical role involved in NPC development. BPIFB1 has previously reported to take tumor-suppressive actions on NPC cell proliferation and migration. Nonetheless, the function of BPIFB1 in immune escape remains largely elusive. Expression pattern on mRNA and protein levels of target genes in NPC patients' samples and cell lines were examined by qRT-PCR, western blot, and immunohistochemistry staining, respectively. The assessment of CD8+ T-cell apoptosis and expression was determined by flow cytometry. Molecular interactions were verified using chromatin immunoprecipitation (ChIP) and luciferase reporter assay. BPIFB1 was downregulated in NPC tumor tissues, exhibiting a negative correlation of PD-L1. Overexpression of BPIFB1 significantly inhibited the expression of PD-L1, suppressing the apoptosis and enhancing the expression of CD8+ T cells. Mechanistically, BPIFB1 was found to repress the expression of STAT1, which was identified to be an upstream activator of PD-L1. Furthermore, the EBV-encoded miR-BART4 overexpressed in NPC cells could directly target and inhibit BPIFB1. This study provided a comprehensive understanding of the molecular mechanism for the upstream and downstream pathway of BPIFB1 related with immune escape, indicating a novel approach for the treatment of NPC.

10.
Dev Psychobiol ; 66(6): e22535, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39106340

RESUMEN

The significance of physiological regulation in relation to behavioral and emotional regulation is well documented, but primarily in economically advantaged contexts. Few studies have been conducted in low- and middle-income countries. We investigated the feasibility and reliability of measuring autonomic nervous system (ANS) activity and behavior during challenge tasks in 30 children aged 8-10 years in Ghana during two visits, 1 week apart. Completeness of ANS data ranged from 80% to 100% across all tasks. There was low-to-moderate test-retest reliability of video mood induction (VMI) emotion ratings and balloon analog risk task (BART) pumps (r = 0.34-0.52). VMI elicited higher targeted emotion ratings in Visit 2 than Visit 1. Respiratory sinus arrhythmia (RSA) was higher, and pre-ejection period (PEP) was longer at Visit 2 than Visit 1 for baseline and both tasks. RSA was higher at baseline than during the VMI anger scene at Visit 1, whereas PEP was shorter at baseline than during all VMI emotion scenes at Visit 2. RSA was higher at baseline than during BART at both visits. In conclusion, ANS data collection within evocative and arousing challenge tasks was feasible in Ghana, and the tasks were generally reliable and effective in eliciting target emotions and risk-taking behavior in this sample.


Asunto(s)
Sistema Nervioso Autónomo , Emociones , Estudios de Factibilidad , Arritmia Sinusal Respiratoria , Humanos , Ghana , Niño , Masculino , Femenino , Sistema Nervioso Autónomo/fisiología , Reproducibilidad de los Resultados , Arritmia Sinusal Respiratoria/fisiología , Emociones/fisiología , Regulación Emocional/fisiología , Conducta Infantil/fisiología
11.
Ann Hum Genet ; 87(3): 137-145, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36709419

RESUMEN

INTRODUCTION: The α0 -thalassemia 44.6 kb or Chiang Rai (--CR ) deletion has been reported in northern Thailand and is capable of causing hemoglobin (Hb) H disease and a lethal α-thalassemia genotype, Hb Bart's hydrops fetalis, in this region. However, there are no current data regarding the frequency of --CR nationwide due to a lack of effective diagnostic assay. Therefore, this study aimed to develop a reliable platform for simultaneous genotyping of --CR and two common α0 -thalassemias in Thailand (--SEA and --THAI ) and investigate the frequency of --CR across Thailand. METHODS: Multiplex gap-PCR assay and five renewable plasmid DNA controls for --CR , --SEA , --THAI , α2-globin (HBA2), and ß-actin (ACTB) were newly developed and validated with reference methods. The developed assay was further tested on 1046 unrelated individuals with a reduced mean corpuscular volume (MCV) of less than 75 fl for investigating genotypic and allelic spectrum of --CR . RESULTS: Our developed assay showed 100% concordance with reference methods. The results were valid and reproducible throughout hundreds of reactions. Comparison of the genotypic and allelic spectra revealed that heterozygous --SEA (--SEA /αα) and --SEA alleles were dominant with the frequency of 22.85% (239/1046) and 13.34% (279/2092), respectively. Of these, --THAI and --CR were relatively rare in this population and comparable to each other with the allelic frequency of 0.14% (3/2092). CONCLUSION: This study successfully established a reliable molecular diagnostic platform for genotyping of --CR , --SEA , and --THAI in a single reaction. Additionally, we demonstrated the frequency of --CR in Thailand for the first time and provided knowledge basis for the planning of severe α-thalassemia prevention and control programs in Thailand, where thalassemia is endemic.


Asunto(s)
Talasemia alfa , Femenino , Humanos , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Tailandia , Patología Molecular , Hidropesía Fetal/genética , Eritrocitos
12.
Cogn Affect Behav Neurosci ; 23(3): 788-808, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36890341

RESUMEN

Humans globally are reaping the benefits of longer lives. Yet, longer life spans also require engaging with consequential but often uncertain decisions well into old age. Previous research has yielded mixed findings with regards to life span differences in how individuals make decisions under uncertainty. One factor contributing to the heterogeneity of findings is the diversity of paradigms that cover different aspects of uncertainty and tap into different cognitive and affective mechanisms. In this study, 175 participants (53.14% females, mean age = 44.9 years, SD = 19.0, age range = 16 to 81) completed functional neuroimaging versions of two prominent paradigms in this area, the Balloon Analogue Risk Task and the Delay Discounting Task. Guided by neurobiological accounts of age-related changes in decision-making under uncertainty, we examined age effects on neural activation differences in decision-relevant brain structures, and compared these across multiple contrasts for the two paradigms using specification curve analysis. In line with theoretical predictions, we find age differences in nucleus accumbens, anterior insula, and medial prefrontal cortex, but the results vary across paradigm and contrasts. Our results are in line with existing theories of age differences in decision making and their neural substrates, yet also suggest the need for a broader research agenda that considers how both individual and task characteristics determine the way humans deal with uncertainty.


Asunto(s)
Toma de Decisiones , Asunción de Riesgos , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Incertidumbre , Toma de Decisiones/fisiología , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología
13.
Blood Cells Mol Dis ; 103: 102764, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37336681

RESUMEN

Inherited deletions of upstream regulatory elements of α-globin genes give rise to α-thalassemia, which is an autosomal recessive monogenic disease. However, conventional thalassemia target diagnosis often fails to identify these rare deletions. Here we reported a family with two previous pregnancies of Hb Bart's hydrops fetalis and was seeking for prenatal diagnosis during the third pregnancy. Both parents had low level of Hemoglobin A2 indicating α-thalassemia. Conventional Gap-PCR and PCR-reverse dot blot showed the father carried -SEA deletion but did not identify any variants in the mother. Multiplex ligation-dependent probe amplification identified a deletion containing two HS-40 probes but could not determine the exact region. Finally, a long-read sequencing (LRS)-based approach directly identified that the exact deletion region was chr16: 48,642-132,584, which was located in the α-globin upstream regulatory elements and named (αα)JM after the Jiangmen city. Gap-PCR and Sanger sequencing confirmed the breakpoint. Both the mother and fetus from the third pregnancy carried heterozygous (αα)JM, and the fetus was normally delivered at gestational age of 39 weeks. This study demonstrated that LRS technology had great advantages over conventional target diagnosis methods for identifying rare thalassemia variants and assisted better carrier screening and prenatal diagnosis of thalassemia.


Asunto(s)
Hemoglobinas Anormales , Talasemia alfa , Embarazo , Femenino , Humanos , Lactante , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Globinas alfa/genética , Diagnóstico Prenatal/métodos , Hidropesía Fetal/genética , Reacción en Cadena de la Polimerasa/métodos
14.
J Med Virol ; 95(3): e28667, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36912378

RESUMEN

Epstein-Barr virus (EBV)-encoded BamHI A rightward transcript (BART) microRNAs (miRNAs) play important roles in viral infection and tumorigenesis. The association of sequence variations in the BART miRNA cluster 1 region with diseases remains unclear. Herein, 6 types and 11 subtypes of BART cluster 1 were identified in 354 tumors and healthy donors (HDs) from nasopharyngeal carcinoma (NPC)-endemic and nonendemic China (genotyped data), and 905 EBV genomes retrieved from GenBank from diseased and normal people from around the world (archived data). The distributions of BART cluster 1 types/subtypes between NPC-endemic and nonendemic China; between Asian regions and Africa/Europe & Australia & United States; and among Asian regions (NPC-endemic China, NPC-nonendemic East Asia and Southeast Asia) were significantly different (p < 0.001). The subtype BART-D2 was not found outside Asia and was only common in NPC-endemic China. More importantly, BART-D2 had a higher frequency in NPCs than in HDs in NPC-endemic China (genotyped data, 78.0% vs. 44.1%, p < 0.001; achieved data, 89.3% vs. 43.7%, p < 0.001), and was also more frequent in NPCs than in HDs, gastric carcinomas, and lymphomas in NPC-nonendemic China (genotyped data, 27.9% vs. 1.9%, 2.4%, and 0.0%, p < 0.001). BART-D2 was preferentially linked with the high-risk subtypes for NPC previously reported, 162476C or 163364T, in the BALF2 gene, and was associated with NPC risk (p < 0.01). In vitro experiments showed that BART-D2 affected the expression of some mature BART miRNAs. These findings demonstrate geographically restricted variations of BART cluster 1 and identify distinct subtype that is confined to NPC-endemic China and is associated with NPC.


Asunto(s)
Infecciones por Virus de Epstein-Barr , MicroARNs , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , MicroARNs/genética , Herpesvirus Humano 4/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/epidemiología , Neoplasias Nasofaríngeas/epidemiología , Neoplasias Nasofaríngeas/genética
15.
J Med Virol ; 95(4): e28725, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37185865

RESUMEN

Epstein-Barr virus (EBV) infection is associated with the occurrence and development of gastric cancer (GC). Methyl methanesulfonate and ultraviolet-sensitive gene 81 (MUS81) is the catalytic component of a structure-specific endonuclease and plays an important role in chromosomal stability. However, the link between EBV infection and MUS81 remains unclear. In the present study, we found that MUS81 expression was much lower in EBV-associated GC cells than in EBV-negative GC. MUS81 acts as an oncogene in GC by inducing the cell migration and proliferation. Western blot and luciferase reporter assays revealed that miR-BART9-5p directly targeted MUS81 and downregulated its expression. Additionally, overexpression of MUS81 in EBV-positive GC cells inhibited the expression of EBV nuclear antigen 1 (EBNA1). EBNA1 is critical for the pathogenesis of EBV-associated tumors and the maintenance of a stable copy number of the viral genomes. Altogether, these results indicated that the lowering MUS81 expression might be a mechanism by EBV to maintain its latent infection.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Infección Latente , MicroARNs , Neoplasias Gástricas , Humanos , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/genética , Metilmetanosulfonato/metabolismo , Regulación hacia Abajo , Neoplasias Gástricas/genética , MicroARNs/genética , MicroARNs/metabolismo , Movimiento Celular , Proliferación Celular , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endonucleasas/genética , Endonucleasas/metabolismo
16.
Cerebellum ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37779173

RESUMEN

Cognitive and affective sequelae of cerebellar disease are receiving increased attention, but their actual rate of occurrence remains unclear. Complaints may have a significant impact on patients, affecting social behavior and psychological well-being. This study aims to explore the extent of subjective cognitive and affective symptoms in patients with degenerative ataxias in the Netherlands. An explorative study was set up in a heterogeneous group of degenerative ataxia patients. Self-reported cognition was evaluated in terms of executive functioning and affect (Dysexecutive Questionnaire/DEX), and memory/attention (Cognitive Failures Questionnaire/CFQ). The Daily Living Questionnaire (DLQ) was administered to quantify the impact on daily life. Furthermore, informants completed questionnaires to obtain insight into patients' self-awareness and social cognition (Observable Social Cognition Rating Scale/OSCARS). This study shows that subjective complaints in the domains of (1) executive functioning and/or (2) memory and attention were reported by 29% of all patients (n = 24/84). In addition, more difficulties in daily life in terms of language/comprehension and community/participation were reported, and this was more common for patients with cognitive complaints than those without. Discrepancies between patients and informants about executive functioning were present in both directions. Deficits in social cognition were not identified at the group level, but more social-cognitive problems were observed in patients with more executive problems rated by informants. Taken together, our findings indicate that cognitive complaints are common in patients with degenerative cerebellar disorders and have an impact on daily life functioning. These results may help to increase awareness of cognitive symptoms and their impact in patients with cerebellar ataxia, their significant others, and professional caregivers.

17.
Biometrics ; 79(4): 3252-3265, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36718599

RESUMEN

Analysis of observational studies increasingly confronts the challenge of determining which of a possibly high-dimensional set of available covariates are required to satisfy the assumption of ignorable treatment assignment for estimation of causal effects. We propose a Bayesian nonparametric approach that simultaneously (1) prioritizes inclusion of adjustment variables in accordance with existing principles of confounder selection; (2) estimates causal effects in a manner that permits complex relationships among confounders, exposures, and outcomes; and (3) provides causal estimates that account for uncertainty in the nature of confounding. The proposal relies on specification of multiple Bayesian additive regression trees models, linked together with a common prior distribution that accrues posterior selection probability to covariates on the basis of association with both the exposure and the outcome of interest. A set of extensive simulation studies demonstrates that the proposed method performs well relative to similarly-motivated methodologies in a variety of scenarios. We deploy the method to investigate the causal effect of emissions from coal-fired power plants on ambient air pollution concentrations, where the prospect of confounding due to local and regional meteorological factors introduces uncertainty around the confounding role of a high-dimensional set of measured variables. Ultimately, we show that the proposed method produces more efficient and more consistent results across adjacent years than alternative methods, lending strength to the evidence of the causal relationship between SO2 emissions and ambient particulate pollution.


Asunto(s)
Contaminación del Aire , Teorema de Bayes , Contaminación del Aire/efectos adversos , Causalidad , Simulación por Computador , Incertidumbre
18.
Biometrics ; 79(4): 3023-3037, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36932826

RESUMEN

Many popular survival models rely on restrictive parametric, or semiparametric, assumptions that could provide erroneous predictions when the effects of covariates are complex. Modern advances in computational hardware have led to an increasing interest in flexible Bayesian nonparametric methods for time-to-event data such as Bayesian additive regression trees (BART). We propose a novel approach that we call nonparametric failure time (NFT) BART in order to increase the flexibility beyond accelerated failure time (AFT) and proportional hazard models. NFT BART has three key features: (1) a BART prior for the mean function of the event time logarithm; (2) a heteroskedastic BART prior to deduce a covariate-dependent variance function; and (3) a flexible nonparametric error distribution using Dirichlet process mixtures (DPM). Our proposed approach widens the scope of hazard shapes including nonproportional hazards, can be scaled up to large sample sizes, naturally provides estimates of uncertainty via the posterior and can be seamlessly employed for variable selection. We provide convenient, user-friendly, computer software that is freely available as a reference implementation. Simulations demonstrate that NFT BART maintains excellent performance for survival prediction especially when AFT assumptions are violated by heteroskedasticity. We illustrate the proposed approach on a study examining predictors for mortality risk in patients undergoing hematopoietic stem cell transplant (HSCT) for blood-borne cancer, where heteroskedasticity and nonproportional hazards are likely present.


Asunto(s)
Aprendizaje Automático , Programas Informáticos , Humanos , Teorema de Bayes , Modelos de Riesgos Proporcionales , Incertidumbre , Modelos Estadísticos , Simulación por Computador
19.
Cell Biol Toxicol ; 39(2): 537-556, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35844005

RESUMEN

OBJECTIVE: To explore the effects of exosomes loaded with circular RNA PARD3 on EBV-miR-BART4-induced stemness and resistance of cisplatin in nasopharyngeal carcinoma side population (NPC-SP) cells through the miR-579-3p/SIRT1/SSRP1 axis. METHODS: Sixty-five cancer tissues and 65 noncancerous tissues were collected from NPC patients or patients with rhinitis. The expressions of circPARD3, miR-579-3p, SIRT1, and SSRP1 were detected by qRT-PCR, western blot, or immunohistochemistry. In vivo tumor formation assay was performed in nude mice. Immunofluorescence and qRT-PCR were conducted for the determination of CD44 and CD133 expressions, and flow cytometry combined with Hoechst 33,342 dye efflux for identifying SP cells, CCK-8 and EdU assays for cell proliferation, and Transwell assay for migration and invasion. RESULTS: CircPARD3, SIRT1, and SSRP1 were upregulated while miR-579-3p was downregulated in NPC tissues and cells. CircPARD3 was positively correlated with the expressions of SIRT1 and SSRP1, and miR-579-3p was negatively correlated with circPARD3, SIRT1, and SSRP1. Exosomes loaded with circPARD3 promoted EBV-miR-BART4-induced stemness and cisplatin resistance in NPC-SP cells, while miR-579-3p reversed the effect of exosomal circPARD3 on EBV-miR-BART4-induced stemness and cisplatin resistance in NPC-SP cells. Additionally, miR-579-3p suppressed EBV-miR-BART4-induced stemness and cisplatin resistance in NPC-SP cells by regulating SIRT1. SIRT1 upregulated SSRP1 expression by catalyzing H3K4 methylation and down-regulation of SSRP1 reversed the effect of SIRT1 on EBV-miR-BART4-induced stemness and cisplatin resistance in NPC-SP cells. CONCLUSION: Exosomes loaded with circPARD3 promoted EBV-miR-BART4-induced stemness and cisplatin resistance in NPC-SP cells through the miR-579-3p/SIRT1/SSRP1 axis. Graphical Headlights • EBV-miR-BART4 induces the stemness and resistance of NPC-SP cells. • CircPARD3 regulates SIRT1 by miR-579-3p. • SIRT1 regulates SSRP1 expression by histone methylation. • Exosomes loaded with circPARD3 promotes EBV-miR-BART4-induced NPC-SP cell stemness and resistance by the miR-579-3p/SIRT1/SSRP1 axis.


Asunto(s)
Exosomas , MicroARNs , Neoplasias Nasofaríngeas , Animales , Ratones , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Cisplatino/farmacología , Cisplatino/uso terapéutico , MicroARNs/genética , MicroARNs/metabolismo , Células de Población Lateral/metabolismo , Células de Población Lateral/patología , Exosomas/genética , Exosomas/metabolismo , Ratones Desnudos , Sirtuina 1/genética , Sirtuina 1/metabolismo , Línea Celular Tumoral , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica
20.
Virus Genes ; 59(5): 703-715, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37535140

RESUMEN

Epstein-Barr virus (EBV) is a human tumor-associated virus that encodes various microRNAs. EBV infection causes a variety of malignant tumors, including nasopharyngeal carcinoma and gastric cancer, etc. EBV-associated gastric cancer (EBVaGC) has unique molecular characteristics from other gastric cancers, but its pathogenic mechanism remains unclear. In recent years, erythropoietin-producing human hepatocellular 2 (EphA2) has been reported to be highly expressed in various cancers and promote tumor growth and metastasis. As an important cancer oncogene, EphA2 is a potential therapeutic target. However, whether EBV is involved in the regulation of EphA2 and thus affects the progression of EBVaGC remains unclear. In this study, we found that the expression of EphA2 in EBVaGC cells was significantly lower than that in EBV-negative gastric cancer (EBVnGC) cells. Additionally, overexpression of EphA2 in EBVaGC cells promoted migration and proliferation, and inhibited autophagy. EBV-miR-BART1-3p and BART18-5p were found to target the 3'-UTR of EphA2 and down-regulate its expression. Our results suggest that EBV may be involved in gastric cancer progression by targeting EphA2 through BART1-3p and BART18-5p.


Asunto(s)
Carcinoma Hepatocelular , Infecciones por Virus de Epstein-Barr , Eritropoyetina , Neoplasias Hepáticas , MicroARNs , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , MicroARNs/genética , MicroARNs/metabolismo , Movimiento Celular/genética , Proliferación Celular/genética , Autofagia/genética , Eritropoyetina/metabolismo
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