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1.
SLAS Technol ; 28(6): 384-392, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37925157

RESUMEN

Cholera is a waterborne disease caused by Vibrio cholerae bacteria generally transmitted through contaminated food or water sources. Although it has been eradicated in most Western countries, cholera continues to be a highly transmitted and lethal disease in several African and Southeast Asian countries. Unfortunately, current diagnostic methods for cholera have challenges including high cost or delayed diagnoses that can lead to increased disease transmission during pandemics, while current treatments such as therapeutic drugs and vaccines have limited efficacy against drug-resistant serogroups of Vibrio cholerae. As such, new solutions that can treat cholera in an efficient manner that avoids Vibrio cholerae's adaptive immunity are needed. Nanoparticles (NPs) are a suitable platform for enhancing current theranostic tools because of their biocompatibility and ability to improve drug circulation and targeting. Nanoparticle surfaces can also be modified with various protein receptors targeting cholera toxins produced by Vibrio cholerae. This review will address recent developments in diagnostics, therapeutics, and prevention against cholera particularly focusing on the use of metal-based nanoparticles and organic nanoparticles. We will then discuss future directions regarding nanoparticle research for cholera.


Asunto(s)
Cólera , Nanopartículas del Metal , Vibrio cholerae , Humanos , Cólera/diagnóstico , Cólera/prevención & control
2.
PLoS One ; 18(1): e0278702, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36701282

RESUMEN

AIM: The study aimed to determine potential risk factors associated with Premenstrual Syndrome and Premenstrual Dysphoric Disorder. METHODS: Three hundred two female student participants who were 18-45 years old completed a questionnaire including demographic characteristics, lifestyle factors, and a Vietnamese Premenstrual Syndrome Screening Tool. We then followed up participants during at least two menstrual cycles using the Daily Record of Severity of Problems. The Premenstrual Syndrome and Premenstrual Dysphoric Disorder diagnosis was established using The Carolina Premenstrual Assessment Scoring System, based on the American College of Obstetrics and Gynecology and Diagnostic and Statistical Manual of Mental Disorders. RESULTS: According to the Carolina Premenstrual Assessment Scoring System, 35 out of 302 students (11.6%; 95%CI: 8.2-15.7%) met the diagnosis of PMS (31 students) or PMDD (4 students). We found that age at menarche (PR = 0.77, 95%CI: 0.63-0.96), having negative Rh blood type (PR = 4.43, 95%CI: 1.95 to 10.08), being moderately depressed or higher (PR = 2.81, 95%CI: 1.24 to 6.36), and consuming caffeine more than three times per week were statistically associated with having Premenstrual Syndrome or Premenstrual Dysphoric Disorder after adjusting for other variables. CONCLUSION: The prominent risk factors for Premenstrual Syndrome and Premenstrual Dysphoric Disorder were negative Rhesus blood type, menarche age, caffeine consumption, and self-reported depression.


Asunto(s)
Trastorno Disfórico Premenstrual , Síndrome Premenstrual , Estudiantes de Medicina , Humanos , Femenino , Trastorno Disfórico Premenstrual/epidemiología , Trastorno Disfórico Premenstrual/etiología , Estudios Transversales , Cafeína , Síndrome Premenstrual/epidemiología
3.
Antioxidants (Basel) ; 11(12)2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36552553

RESUMEN

Organisms are continually exposed to exogenous and endogenous sources of reactive oxygen species (ROS) and other oxidants that have both beneficial and deleterious effects on the cell. ROS have important roles in a wide range of physiological processes; however, high ROS levels are associated with oxidative stress and disease progression. Oxidative stress has been implicated in nearly all major human diseases, from neurogenerative diseases and neuropsychiatric disorders to cardiovascular disease, diabetes, and cancer. Antioxidant defence systems have evolved as a means of protection against oxidative stress, with the transcription factor Nrf2 as the key regulator. Nrf2 is responsible for regulating an extensive panel of antioxidant enzymes involved in the detoxification and elimination of oxidative stress and has been extensively studied in the disease contexts. This review aims to provide the reader with a general overview of oxidative stress and Nrf2, including basic mechanisms of Nrf2 activation and regulation, and implications in various major human diseases.

4.
Antioxidants (Basel) ; 11(2)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35204126

RESUMEN

Cells that experience high levels of oxidative stress respond by inducing antioxidant proteins through activation of the protein transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 is negatively regulated by the E3 ubiquitin ligase Kelch-like ECH-associated protein 1 (Keap1), which binds to Nrf2 to facilitate its ubiquitination and ensuing proteasomal degradation under basal conditions. Here, we studied protein folding and misfolding in Nrf2 and Keap1 in yeast, mammalian cells, and purified proteins under oxidative stress conditions. Both Nrf2 and Keap1 are susceptible to protein misfolding and inclusion formation upon oxidative stress. We propose that the intrinsically disordered regions within Nrf2 and the high cysteine content of Keap1 contribute to their oxidation and the ensuing misfolding. Our work reveals previously unexplored aspects of Nrf2 and Keap1 regulation and/or dysregulation by oxidation-induced protein misfolding.

5.
Dis Model Mech ; 15(4)2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35088844

RESUMEN

Nrf2 is the master transcriptional regulator of cellular responses against oxidative stress. It is chiefly regulated by Keap1, a substrate adaptor protein that mediates Nrf2 degradation. Nrf2 activity is also influenced by many other protein interactions that provide Keap1-independent regulation. To study Nrf2 regulation, we established and characterized yeast models expressing human Nrf2 (also known as NFE2L2), Keap1 and other proteins that interact with and regulate Nrf2. Yeast models have been well established as powerful tools to study protein function and genetic and physical protein-protein interactions. In this work, we recapitulate previously described Nrf2 interactions in yeast and discover that Nrf2 interacts with the molecular chaperone Hsp90. Our work establishes yeast as a useful tool to study Nrf2 interactions and provides new insight into the crosstalk between the antioxidant response and the heat shock response.


Asunto(s)
Factor 2 Relacionado con NF-E2 , Saccharomyces cerevisiae , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Humanos , Proteína 1 Asociada A ECH Tipo Kelch , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Saccharomyces cerevisiae/metabolismo
6.
Int J Mol Sci ; 22(14)2021 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-34299054

RESUMEN

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription regulator that plays a pivotal role in coordinating the cellular response to oxidative stress. Through interactions with other proteins, such as Kelch-like ECH-associated protein 1 (Keap1), CREB-binding protein (CBP), and retinoid X receptor alpha (RXRα), Nrf2 mediates the transcription of cytoprotective genes critical for removing toxicants and preventing DNA damage, thereby playing a significant role in chemoprevention. Dysregulation of Nrf2 is linked to tumorigenesis and chemoresistance, making Nrf2 a promising target for anticancer therapeutics. However, despite the physiological importance of Nrf2, the molecular details of this protein and its interactions with most of its targets remain unknown, hindering the rational design of Nrf2-targeted therapeutics. With this in mind, we used a combined bioinformatics and experimental approach to characterize the structure of full-length Nrf2 and its interaction with Keap1. Our results show that Nrf2 is partially disordered, with transiently structured elements in its Neh2, Neh7, and Neh1 domains. Moreover, interaction with the Kelch domain of Keap1 leads to protection of the binding motifs in the Neh2 domain of Nrf2, while the rest of the protein remains highly dynamic. This work represents the first detailed structural characterization of full-length Nrf2 and provides valuable insights into the molecular basis of Nrf2 activity modulation in oxidative stress response.


Asunto(s)
Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/química , Factor 2 Relacionado con NF-E2/metabolismo , Sitios de Unión , Humanos , Proteínas Intrínsecamente Desordenadas/genética , Proteína 1 Asociada A ECH Tipo Kelch/genética , Modelos Moleculares , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo , Unión Proteica , Estructura Terciaria de Proteína
7.
Invest Ophthalmol Vis Sci ; 62(3): 20, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33724292

RESUMEN

Purpose: Diabetic retinopathy (DR) remains a pressing issue worldwide. Abnormal angiogenesis is a distinct vascular lesion in DR, and research has established that vascular endothelial growth factor A (VEGF-A) is a primary mediator of such changes. However, limitations in current anti-VEGF therapies suggest that our understanding of molecular networks underlying ocular angiogenesis remains far from complete. Based on our long non-coding RNA (lncRNA) array analyses, HOX antisense intergenic RNA (HOTAIR) was identified as one of the top upregulated lncRNAs in high glucose-cultured human retinal endothelial cells (HRECs). Given the well-documented roles of HOTAIR in cancer, no studies have examined the epigenetic implications of HOTAIR in DR, and we investigated such relationships herein. Methods: We used HRECs exposed to various glucose concentrations and epigenetic modulators to examine HOTAIR, angiogenic, and DR-related molecular markers. Oxidative stress, angiogenesis, and mitochondrial dysfunction were assessed. Retinal tissues of diabetic rodents and the vitreous humor and serum of patients with proliferative DR were also investigated. Results: Hyperglycemia significantly augmented HOTAIR expression in HRECs and promoted angiogenesis, oxidative damage, and mitochondrial aberrations. Similarly, vitreous humor and serum from proliferative DR patients and retinas from diabetic animals demonstrated increased HOTAIR expression compared to non-diabetic controls. HOTAIR knockdown protected against glucose-induced increases of angiogenic and diabetes-associated molecules in the retina. Mechanistically, we showed that HOTAIR exerts its capabilities by preventing oxidative stress and modulating epigenetic pathways involving histone methylation, histone acetylation, DNA methylation, and transcription factors. Conclusions: Our findings suggest that HOTAIR is a critical lncRNA in the pathogenesis of DR and may potentially be important for diagnostic and therapeutic targeting.


Asunto(s)
Retinopatía Diabética/genética , Epigénesis Genética/genética , Regulación de la Expresión Génica/fisiología , ARN Largo no Codificante/genética , Neovascularización Retiniana/genética , Animales , Vasos Sanguíneos/fisiología , Células Cultivadas , Islas de CpG/genética , Metilación de ADN , Diabetes Mellitus Experimental , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Glucosa/farmacología , Humanos , Hibridación Fluorescente in Situ , Masculino , Ratones Endogámicos C57BL , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/metabolismo , Vasos Retinianos/patología
8.
Eur Urol ; 79(1): 141-149, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33148472

RESUMEN

BACKGROUND: Distinguishing indolent from aggressive prostate cancer remains a key challenge for decision making regarding prostate cancer management. A growing number of biomarkers are now available to help address this need, but these have rarely been examined together in the same patients to determine their potentially additive value. OBJECTIVE: To determine whether two previously validated plasma markers (transforming growth factor ß1 [TGFß1] and interleukin-6 soluble receptor [IL6-SR]) and two validated tissue scores (the Genomic Evaluators of Metastatic Prostate Cancer [GEMCaP] and cell cycle progression [CCP] scores) can improve on clinical parameters in predicting adverse pathology after prostatectomy, and how much they vary within tumors with heterogeneous Gleason grade. DESIGN, SETTING, AND PARTICIPANTS: A case-control study was conducted among men with low-risk cancers defined by biopsy grade group (GG) 1, prostate-specific antigen (PSA) ≤10 ng/mL, and clinical stage ≤ T2 who underwent immediate prostatectomy. We collected paraffin-fixed prostatectomy tissue and presurgical plasma samples from 381 cases from the University of California, San Francisco, and 260 cases from the University of Washington. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Pathologic outcomes were minor upgrading/upstaging (GG 2 or pT3a) or major upgrading/upstaging (GG ≥ 3 or ≥ pT3b), and multinomial regression was performed to determine putative markers' ability to predict these outcomes, controlling for PSA, percent of positive biopsy cores, age, and clinical site. For upgraded tumors, a secondary analysis of the GEMCaP and CCP scores from the higher-grade tumor was also performed to evaluate for heterogeneity. RESULTS AND LIMITATIONS: Overall, 357 men had no upgrading/upstaging event at prostatectomy, 236 had a minor event, and 67 had a major event. Neither TGFß1 nor IL6-SR was statistically significantly associated with any upgrading/upstaging. On the contrary, both the CCP and the GEMCaP score obtained from Gleason pattern 3 tissue were directly associated with minor and major upgrading/upstaging on univariate analysis. The two scores correlated with each other, but weakly. On multinomial analysis including both scores in the model, the CCP score predicted minor upgrading/upstaging (odds ratio [OR] 1.62, 95% confidence interval [CI] 1.05-2.49) and major upgrading/upstaging (OR 2.26, 95% CI 1.05-4.90), p =  0.04), and the GEMCaP score also predicted minor upgrading/upstaging (OR 1.05, 95% CI 1.03-1.08) and major upgrading/upstaging (OR 1.07, 95% CI 1.04-1.11), p <  0.01). The other clinical parameters were not significant in this model. Among upgraded tumors including both Gleason patterns 3 and 4, both the GEMCaP and the CCP score tended to be higher from the higher-grade tumor. The main limitation was the use of virtual biopsies from prostatectomy tissue as surrogates for prostate biopsies. CONCLUSIONS: Biomarker signatures based on analyses of both DNA and RNA significantly and independently predict adverse pathology among men with clinically low-risk prostate cancer undergoing prostatectomy. PATIENT SUMMARY: Validated biomarker scores derived from both prostate cancer DNA and prostate cancer RNA can add independent information to help predict outcomes after prostatectomy.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Próstata/química , Neoplasias de la Próstata/patología , Anciano , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prostatectomía , Neoplasias de la Próstata/cirugía
9.
J Vis Exp ; (160)2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32568244

RESUMEN

Nearly universal among organisms, circadian rhythms coordinate biological activity to earth's orbit around the sun. To identify factors creating this rhythm and to understand the resulting outputs, entrainment of model organisms to defined circadian time-points is required. Here we detail a procedure to entrain many Drosophila to a defined circadian rhythm. Furthermore, we detail post-entrainment steps to prepare samples for immunofluorescence, nucleic acid, or protein extraction-based analysis.


Asunto(s)
Ritmo Circadiano/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/patogenicidad , Animales
10.
Biotechniques ; 67(6): 299-305, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31687836

RESUMEN

Drosophila melanogaster possesses a complex nervous system, regulating sophisticated behavioral outputs, that serves as a powerful model for dissecting molecular mechanisms underlying neuronal function and neurodegenerative disease. Immunofluorescence techniques provide a way to visualize the spatiotemporal organization of these networks, permitting observation of their development, functional location, remodeling and, eventually, degradation. However, basic immunostaining techniques do not always result in efficient antibody penetration through the brain, and supplemental techniques to enhance permeability can compromise structural integrity, altering spatial organization. Here, slow freezing of brains is shown to facilitate antibody permeability without loss of antibody specificity or brain integrity. To demonstrate the advantages of this freezing technique, the results of two commonly used permeation methods - detergent-based and partial proteolytic digestion - are compared.


Asunto(s)
Encéfalo/metabolismo , Drosophila melanogaster/metabolismo , Técnica del Anticuerpo Fluorescente/métodos , Neuronas/metabolismo , Animales , Proteínas de Drosophila/metabolismo , Congelación , Enfermedades Neurodegenerativas/metabolismo
11.
FEBS J ; 286(10): 1859-1876, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30719832

RESUMEN

The assembly of proteins into dimers and oligomers is a necessary step for the proper function of transcription factors, muscle proteins, and proteases. In uncontrolled states, oligomerization can also contribute to illnesses such as Alzheimer's disease. The S100 protein family is a group of dimeric proteins that have important roles in enzyme regulation, cell membrane repair, and cell growth. Most S100 proteins have been examined in their homodimeric state, yet some of these important proteins are found in similar tissues implying that heterodimeric molecules can also be formed from the combination of two different S100 members. In this work, we have established co-expression methods in order to identify and quantify the distribution of homo- and heterodimers for four specific pairs of S100 proteins in their calcium-free states. The split GFP trap methodology was used in combination with other GFP variants to simultaneously quantify homo- and heterodimeric S100 proteins in vitro and in living cells. For the specific S100 proteins examined, NMR, mass spectrometry, and GFP trap experiments consistently show that S100A1:S100B, S100A1:S100P, and S100A11:S100B heterodimers are the predominant species formed compared to their corresponding homodimers. We expect the tools developed here will help establish the roles of S100 heterodimeric proteins and identify how heterodimerization might alter the specificity for S100 protein action in cells.


Asunto(s)
Proteínas S100/química , Proteínas S100/metabolismo , Proteínas Fluorescentes Verdes/química , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , Espectroscopía de Resonancia Magnética , Multimerización de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas S100/genética , Espectrometría de Masa por Ionización de Electrospray
12.
J Urol ; 199(3): 719-725, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28941923

RESUMEN

PURPOSE: We aimed to validate GEMCaP (Genomic Evaluators of Metastatic Cancer of the Prostate) as a novel copy number signature predictive of prostate cancer recurrence. MATERIALS AND METHODS: We randomly selected patients who underwent radical prostatectomy at Cleveland Clinic or University of Rochester from 2000 to 2005. DNA isolated from the cancer region was extracted and subjected to high resolution array comparative genomic hybridization. A high GEMCaP score was defined as 20% or greater of genomic loci showing copy number gain or loss in a given tumor. Cox regression was used to evaluate associations between the GEMCaP score and the risk of biochemical recurrence. RESULTS: We report results in 140 patients. Overall 38% of patients experienced recurrence with a median time to recurrence of 45 months. Based on the CAPRA-S (Cancer of the Prostate Risk Assessment Post-Surgical) score 39% of the patients were at low risk, 42% were at intermediate risk and 19% were at high risk. The GEMCaP score was high (20% or greater) in 31% of the cohort. A high GEMCaP score was associated with a higher risk of biochemical recurrence (HR 2.69, 95% CI 1.51-4.77) and it remained associated after adjusting for CAPRA-S score and age (HR 1.94, 95% CI 1.06-3.56). The C-index of GEMCaP alone was 0.64, which improved when combined with the CAPRA-S score and patient age (C-index = 0.75). CONCLUSIONS: A high GEMCaP score was associated with biochemical recurrence in 2 external cohorts. This remained true after adjusting for clinical and pathological factors. The GEMCaP biomarker could be an efficient and effective clinical risk assessment tool to identify patients with prostate cancer for early adjuvant therapy.


Asunto(s)
ADN de Neoplasias/genética , Recurrencia Local de Neoplasia/diagnóstico , Próstata/patología , Prostatectomía/métodos , Neoplasias de la Próstata/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Hibridación Genómica Comparativa , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Valor Predictivo de las Pruebas , Pronóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Medición de Riesgo
13.
Microbes Environ ; 32(2): 174-179, 2017 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-28592722

RESUMEN

Extracellular DNA (exDNA) is released from bacterial cells through various processes. The antibiotic resistance genes (ARGs) coded on exDNA may be horizontally transferred among bacterial communities by natural transformation. We quantitated the released/leaked tetracycline resistance gene, tet(M) over time under grazing stress by ciliates and heterotrophic nanoflagellates (HNFs), and found that extracellular tet(M) (ex-tetM) increased with bacterial grazing. Separate microcosms containing tet(M)-possessing bacteria with ciliates or HNFs were prepared. The copy number of ex-tetM in seawater in the ciliate microcosm rapidly increased until 3 d after the incubation, whereas that in the HNF microcosm showed a slower increase until 20 d. The copy number of ex-tetM was stable in both cases throughout the incubation period, suggesting that extracellular ARGs are preserved in the environment, even in the presence of grazers. Additionally, ARGs in bacterial cells were constant in the presence of grazers. These results suggest that ARGs are not rapidly extinguished in a marine environment under grazing stress.


Asunto(s)
Proteínas Bacterianas/genética , Cilióforos , ADN Bacteriano/aislamiento & purificación , Farmacorresistencia Microbiana/genética , Agua de Mar/análisis , Proteínas Bacterianas/aislamiento & purificación , Procesos Heterotróficos
14.
Cancer Lett ; 380(1): 144-52, 2016 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-27343980

RESUMEN

Improvements in technologies to yield purer circulating tumor cells (CTCs) will enable a broader range of clinical applications. We have previously demonstrated the use of a commercially available cell-adhesion matrix (CAM) assay to capture invasive CTCs (iCTCs). To improve the purity of the isolated iCTCs, here we used fluorescence-activated cell sorting (FACS) in combination with the CAM assay (CAM + FACS). Our results showed an increase of median purity from the CAM assay to CAM + FACS for the spiked-in cell lines and patient samples analyzed from three different metastatic cancer types: castration resistant prostate cancer (mCRPC), non-small cell lung cancer (mNSCLC) and pancreatic ductal adenocarcinoma cancer (mPDAC). Copy number profiles for spiked-in mCRPC cell line and mCRPC patient iCTCs were similar to expected mCRPC profiles and a matched biopsy. A somatic epidermal growth factor receptor (EGFR) mutation specific to mNSCLC was observed in the iCTCs recovered from EGFR(+) mNSCLC cell lines and patient samples. Next-generation sequencing (NGS) of spiked-in pancreatic cancer cell line and mPDAC patient iCTCs showed mPDAC common mutations. CAM + FACS iCTC enrichment enables multiple downstream genomic characterizations across different tumor types.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma Ductal Pancreático/patología , Separación Celular/métodos , Citometría de Flujo , Genómica , Neoplasias Pulmonares/patología , Células Madre Neoplásicas/patología , Neoplasias Pancreáticas/patología , Neoplasias de la Próstata Resistentes a la Castración/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Colágeno/metabolismo , Análisis Mutacional de ADN , Receptores ErbB/genética , Predisposición Genética a la Enfermedad , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Mutación , Invasividad Neoplásica , Células Madre Neoplásicas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fenotipo , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo
15.
J Neurophysiol ; 116(2): 369-79, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27121574

RESUMEN

To perceive, the brain must interpret stimulus-evoked neural activity. This is challenging: The stochastic nature of the neural response renders its interpretation inherently uncertain. Perception would be optimized if the brain used Bayesian inference to interpret inputs in light of expectations derived from experience. Bayesian inference would improve perception on average but cause illusions when stimuli violate expectation. Intriguingly, tactile, auditory, and visual perception are all prone to length contraction illusions, characterized by the dramatic underestimation of the distance between punctate stimuli delivered in rapid succession; the origin of these illusions has been mysterious. We previously proposed that length contraction illusions occur because the brain interprets punctate stimulus sequences using Bayesian inference with a low-velocity expectation. A novel prediction of our Bayesian observer model is that length contraction should intensify if stimuli are made more difficult to localize. Here we report a tactile psychophysical study that tested this prediction. Twenty humans compared two distances on the forearm: a fixed reference distance defined by two taps with 1-s temporal separation and an adjustable comparison distance defined by two taps with temporal separation t ≤ 1 s. We observed significant length contraction: As t was decreased, participants perceived the two distances as equal only when the comparison distance was made progressively greater than the reference distance. Furthermore, the use of weaker taps significantly enhanced participants' length contraction. These findings confirm the model's predictions, supporting the view that the spatiotemporal percept is a best estimate resulting from a Bayesian inference process.


Asunto(s)
Vías Aferentes/fisiología , Teorema de Bayes , Encéfalo/fisiología , Percepción/fisiología , Tacto/fisiología , Adolescente , Adulto , Análisis de Varianza , Conducta de Elección/fisiología , Femenino , Antebrazo/inervación , Humanos , Masculino , Desempeño Psicomotor/fisiología , Psicofísica , Umbral Sensorial/fisiología , Factores de Tiempo , Adulto Joven
16.
Cancer Res ; 76(7): 1860-8, 2016 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-26921337

RESUMEN

Prostate cancer is the most frequently diagnosed and second most fatal nonskin cancer among men in the United States. African American men are two times more likely to develop and die of prostate cancer compared with men of other ancestries. Previous whole genome or exome tumor-sequencing studies of prostate cancer have primarily focused on men of European ancestry. In this study, we sequenced and characterized somatic mutations in aggressive (Gleason ≥7, stage ≥T2b) prostate tumors from 24 African American patients. We describe the locations and prevalence of small somatic mutations (up to 50 bases in length), copy number aberrations, and structural rearrangements in the tumor genomes compared with patient-matched normal genomes. We observed several mutation patterns consistent with previous studies, such as large copy number aberrations in chromosome 8 and complex rearrangement chains. However, TMPRSS2-ERG gene fusions and PTEN losses occurred in only 21% and 8% of the African American patients, respectively, far less common than in patients of European ancestry. We also identified mutations that appeared specific to or more common in African American patients, including a novel CDC27-OAT gene fusion occurring in 17% of patients. The genomic aberrations reported in this study warrant further investigation of their biologic significant role in the incidence and clinical outcomes of prostate cancer in African Americans. Cancer Res; 76(7); 1860-8. ©2016 AACR.


Asunto(s)
Neoplasias de la Próstata/patología , Negro o Afroamericano , Humanos , Masculino , Mutación
17.
Prostate ; 76(4): 339-48, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26585352

RESUMEN

BACKGROUND: Carotenoids are a class of nutrients with antioxidant properties that have been purported to protect against cancer. However, the reported associations between carotenoids and prostate cancer have been heterogeneous and lacking data on interactions with nucleotide sequence variations and genomic biomarkers. OBJECTIVE: To examine the associations between carotenoid levels and the risk of high-grade prostate cancer, also considering antioxidant-related genes and tumor instability. METHODS: We measured plasma levels of carotenoids and genotyped 20 single nucleotide polymorphisms (SNP) in SOD1, SOD2, SOD3, XRCC1, and OGG1 among 559 men with non-metastatic prostate cancer undergoing radical prostatectomy. We performed copy number analysis in a subset of these men (n = 67) to study tumor instability assessed as Fraction of the Genome Altered (FGA). We examined associations between carotenoids, genotypes, tumor instability and risk of high-grade prostate cancer (Gleason grade ≥ 4 + 3) using logistic and linear regression. RESULTS: Circulating carotenoid levels were inversely associated with the risk of high-grade prostate cancer; odds ratios (OR) and 95% confidence intervals (CI) comparing highest versus lowest quartiles were: 0.34 (95% CI: 0.18-0.66) for α-carotene, 0.31 (95% CI: 0.15-0.63) for ß-carotene, 0.55 (0.28-1.08) for lycopene and 0.37 (0.18-0.75) for total carotenoids. SNPs rs25489 in XRCC1, rs699473 in SOD3 and rs1052133 in OGG1 modified these associations for α-carotene, ß-carotene and lycopene, respectively (P ≤ 0.05). The proportion of men with a high degree of FGA increased with Gleason Score (P < 0.001). Among men with Gleason score ≤ 3 + 4, higher lycopene levels were associated with lower FGA (P = 0.04). CONCLUSION: Circulating carotenoids at diagnosis, particularly among men carrying specific somatic variations, were inversely associated with risk of high-grade prostate cancer. In exploratory analyses, higher lycopene level was associated with less genomic instability among men with low-grade disease which is novel and supports the hypothesis that lycopene may inhibit progression of prostate cancer early in its natural history.


Asunto(s)
Carotenoides/sangre , Carotenoides/genética , Inestabilidad Genómica/genética , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/genética , Anciano , Antioxidantes/análisis , Estudios Transversales , Reparación del ADN/genética , Genotipo , Humanos , Licopeno , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Oportunidad Relativa , Polimorfismo de Nucleótido Simple/genética , Próstata/patología , Prostatectomía , Neoplasias de la Próstata/patología , Factores de Riesgo , Superóxido Dismutasa/genética , beta Caroteno/sangre
18.
Mar Environ Res ; 109: 95-102, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26115436

RESUMEN

The biodegradation of proteins in seawater requires various proteases which are commonly thought to be mainly derived from heterotrophic bacteria. We, however, found that protists showed a high protease activity and continuously produced trypsin-type enzymes. The free-living marine heterotrophic ciliate Paranophrys marina together with an associated bacterium was isolated and used for microcosm incubation with different concentrations of killed bacteria as food for 10 days. The results showed that the co-existence of the ciliate with its associated bacterium produced a significant protease activity in both cell-associated and cell-free fractions while that in the associated bacterium only microcosm was negligible. The protease profiles are different between cell-associated and cell-free fractions, and a trypsin-type enzyme hydrolyzing Boc-Val-Leu-Lys-MCA was detected throughout the period in the presence of ciliates. This suggests that ciliates release proteases into the surrounding environment which could play a role in protein digestion outside cells. It has been previously suggested that bacteria are the major transformers in seawater. We here present additional data which indicates that protists, or at least ciliates with their specific enzymes, are a potential player in organic matter degradation in water columns.


Asunto(s)
Cilióforos/enzimología , Péptido Hidrolasas/metabolismo , Proteínas Protozoarias/metabolismo , Pseudomonas aeruginosa/fisiología , Agua de Mar/química , Agua de Mar/microbiología , Agua de Mar/parasitología , Simbiosis
19.
Cancer Lett ; 356(2 Pt B): 404-9, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25304377

RESUMEN

Intraductal papillary mucinous neoplasm (IPMN) is a precursor cystic lesion to pancreatic cancer. With the goal of classifying IPMN cases by risk of progression to pancreatic cancer, we undertook an exploratory next generation sequencing (NGS) based profiling study of miRNAs (miRNome) in the cyst fluids from low grade-benign and high grade-invasive pancreatic cystic lesions. Thirteen miRNAs (miR-138, miR-195, miR-204, miR-216a, miR-217, miR-218, miR-802, miR-155, miR-214, miR-26a, miR-30b, miR-31, and miR-125) were enriched and two miRNAs (miR-451a and miR-4284) were depleted in the cyst fluids derived from invasive carcinomas. Quantitative real-time polymerase chain reaction analysis confirmed that the relative abundance of tumor suppressor miR-216a and miR-217 varied significantly in these cyst fluid samples. Ingenuity Pathway Analysis (IPA) analysis indicated that the genes targeted by the differentially enriched cyst fluid miRNAs are involved in five canonical signaling pathways, including molecular mechanisms of cancer and signaling pathways implicated in colorectal, ovarian and prostate cancers. Our findings make a compelling case for undertaking in-depth analyses of cyst fluid miRNomes for developing informative early detection biomarkers of pancreatic cancer developing from pancreatic cystic lesions.


Asunto(s)
Biomarcadores de Tumor/genética , Líquido Quístico/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , MicroARNs/genética , Quiste Pancreático/genética , Neoplasias Pancreáticas/genética , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Redes Reguladoras de Genes , Humanos , Clasificación del Tumor , Invasividad Neoplásica , Quiste Pancreático/patología , Neoplasias Pancreáticas/patología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Nat Med ; 20(12): 1394-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25401693

RESUMEN

Pediatric brainstem gliomas often harbor oncogenic K27M mutation of histone H3.3. Here we show that GSKJ4 pharmacologic inhibition of K27 demethylase JMJD3 increases cellular H3K27 methylation in K27M tumor cells and demonstrate potent antitumor activity both in vitro against K27M cells and in vivo against K27M xenografts. Our results demonstrate that increasing H3K27 methylation by inhibiting K27 demethylase is a valid therapeutic strategy for treating K27M-expressing brainstem glioma.


Asunto(s)
Apoptosis/efectos de los fármacos , Benzazepinas/farmacología , Neoplasias del Tronco Encefálico/genética , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Histonas/efectos de los fármacos , Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Pirimidinas/farmacología , Animales , Neoplasias del Tronco Encefálico/metabolismo , Línea Celular Tumoral , Niño , Glioma/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji/metabolismo , Metilación/efectos de los fármacos , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto
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