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1.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36361677

RESUMEN

Despite the wide variety of existing therapies, multiple myeloma (MM) remains a disease with dismal prognosis. Choosing the right treatment for each patient remains one of the major challenges. A new approach being explored is the use of ex vivo models for personalized medicine. Two-dimensional culture or animal models often fail to predict clinical outcomes. Three-dimensional ex vivo models using patients' bone marrow (BM) cells may better reproduce the complexity and heterogeneity of the BM microenvironment. Here, we review the strengths and limitations of currently existing patient-derived ex vivo three-dimensional MM models. We analyze their biochemical and biophysical properties, molecular and cellular characteristics, as well as their potential for drug testing and identification of disease biomarkers. Furthermore, we discuss the remaining challenges and give some insight on how to achieve a more biomimetic and accurate MM BM model. Overall, there is still a need for standardized culture methods and refined readout techniques. Including both myeloma and other cells of the BM microenvironment in a simple and reproducible three-dimensional scaffold is the key to faithfully mapping and examining the relationship between these players in MM. This will allow a patient-personalized profile, providing a powerful tool for clinical and research applications.


Asunto(s)
Mieloma Múltiple , Animales , Mieloma Múltiple/genética , Mieloma Múltiple/tratamiento farmacológico , Medicina de Precisión , Modelos Biológicos , Células de la Médula Ósea , Microambiente Tumoral
2.
Invest Clin ; 57(4): 377-87, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29938987

RESUMEN

The molecular diagnosis of haemophilia A (HA) patients has many benefits including diagnosis confirmation and inhibitor risk development prediction. In female carries of a mutation, the molecular diagnosis allows for genetic counseling and prenatal diagnosis, which have become part of the comprehensive care for HA in many countries. Therefore, the aim of this study was to determine the F8 mutations in severe HA (sHA) patients and female carriers. In 12 patients with sHA, the presence of the intron 22 and intron 1 inversions was investigated using an inverse and a conventional PCR method, respectively. In patients negative for the inversions, the F8 gene was screened through conformation sensitive gel electrophoresis (CSGE) and further sequencing. The causative mutation was successfully identified in 6/12 patients, including the novel mutation p.G190C. The mothers of these six patients and those of seven other sHA patients molecularly diagnosed in a previous work were investigated for the presence of the genetic alterations found in their sons. All mothers were found to be carriers. This is the first study conducted in Venezuela which directly analyzes the F8 gene in potential carrier mothers to specifically identify the presence of the mutation that was detected in their sons, and complements a previous study on sHA patients. Our findings will facilitate the implementation of regular screening of HA carriers in our country and will allow a better care of bleeding symptoms and genetic counseling.


Asunto(s)
Factor VIII/genética , Hemofilia A/genética , Heterocigoto , Mutación , Humanos , Masculino , Índice de Severidad de la Enfermedad
3.
Arch Latinoam Nutr ; 66(3): 201-210, 2016 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29870607

RESUMEN

Oxidative stress is an important risk factor for the development of cardiovascular ciseases (CVD) due to the serious damage caused by reactive oxygen species to biomolecules, thus, adequate intake of vitamins with antioxidant properties could prevent or delay the onset of these diseases. The aim of this study was to determine the relationship between antioxidant intake, nutritional factors and biochemical markers in a group of healthy individuals in Caracas, Venezuela. The study included 29 participants between 18-40 years of age who underwent three 24-hour dietary recalls, anthropometric measurements [weight, height, waist circumference (WC), waist-hip ratio (WHR) and % body fat (% BF)] according to the International Biology Program (IBP) methodology. Tn addition, the lipid profile and the concentration of 8-isoprostane as a marker of oxidative stress was determined. The participants took one daily capsule of antioxidant vitamins for.30 days. After treatment with antioxidants, no significant changes in triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (14DL-C) levels were observed. Meanwhile, the 8-isoprostane recorded a significative correlation between before and after treatment (r=0.374; p<0.05). The decline in 8-isoprostane levels was more evident in those individuals with the highest % BF and WC. These findings suggest that antioxidant supplementation decreases oxidative stress in a short period of time, particularly in higher % BF individuals, and might help prevent CVDs.


Asunto(s)
Antioxidantes/administración & dosificación , Enfermedades Cardiovasculares/prevención & control , Suplementos Dietéticos , Conducta Alimentaria , Estrés Oxidativo/efectos de los fármacos , Adolescente , Adulto , Biomarcadores/sangre , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Encuestas sobre Dietas , Dinoprost/análogos & derivados , Dinoprost/sangre , Femenino , Voluntarios Sanos , Humanos , Masculino , Triglicéridos/sangre , Venezuela , Adulto Joven
4.
Front Oncol ; 12: 860849, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35800053

RESUMEN

Multiple myeloma (MM) is a hematological malignancy of clonal antibody-secreting plasma cells (PCs). MM diagnosis and risk stratification rely on bone marrow (BM) biopsy, an invasive procedure prone to sample bias. Liquid biopsies, such as extracellular vesicles (EV) in peripheral blood (PB), hold promise as new minimally invasive tools. Real-world studies analyzing patient-derived EV proteome are rare. Here, we characterized a small EV protein content from PB and BM samples in a cohort of 102 monoclonal gammopathies patients routinely followed in the clinic and 223 PB and 111 BM samples were included. We investigated whether EV protein and particle concentration could predict an MM patient prognosis. We found that a high EV protein/particle ratio, or EV cargo >0.6 µg/108 particles, is related to poorer survival and immune dysfunction. These results were supported at the protein level by mass spectrometry. We report a set of PB EV-proteins (PDIA3, C4BPA, BTN1A1, and TNFSF13) with a new biomarker potential for myeloma patient outcomes. The high proteomic similarity between PB and BM matched pairs supports the use of circulating EV as a counterpart of the BM EV proteome. Overall, we found that the EV protein content is related to patient outcomes, such as survival, immune dysfunction, and possibly treatment response.

5.
Front Immunol ; 13: 909880, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874665

RESUMEN

Multiple myeloma (MM), the third most frequent hematological cancer worldwide, is characterized by the proliferation of neoplastic plasma cells in the bone marrow (BM). One of the hallmarks of MM is a permissive BM microenvironment. Increasing evidence suggests that cell-to-cell communication between myeloma and immune cells via tumor cell-derived extracellular vesicles (EV) plays a key role in the pathogenesis of MM. Hence, we aimed to explore BM immune alterations induced by MM-derived EV. For this, we inoculated immunocompetent BALB/cByJ mice with a myeloma cell line, MOPC315.BM, inducing a MM phenotype. Upon tumor establishment, characterization of the BM microenvironment revealed the expression of both activation and suppressive markers by lymphocytes, such as granzyme B and PD-1, respectively. In addition, conditioning of the animals with MOPC315.BM-derived EV, before transplantation of the MOPC315.BM tumor cells, did not anticipate the disease phenotype. However, it induced features of suppression in the BM milieu, such as an increase in PD-1 expression by CD4+ T cells. Overall, our findings reveal the involvement of MOPC315.BM-derived EV protein content as promoters of immune niche remodeling, strengthening the importance of assessing the mechanisms by which MM may impact the immune microenvironment.


Asunto(s)
Vesículas Extracelulares , Mieloma Múltiple , Animales , Médula Ósea , Línea Celular Tumoral , Vesículas Extracelulares/metabolismo , Ratones , Receptor de Muerte Celular Programada 1/metabolismo , Microambiente Tumoral
6.
Invest. clín ; 57(4): 377-387, dic. 2016. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-841127

RESUMEN

The molecular diagnosis of haemophilia A (HA) patients has many benefits including diagnosis confirmation and inhibitor risk development prediction. In female carries of a mutation, the molecular diagnosis allows for genetic counseling and prenatal diagnosis, which have become part of the comprehensive care for HA in many countries. Therefore, the aim of this study was to determine the F8 mutations in severe HA (sHA) patients and female carriers. In 12 patients with sHA, the presence of the intron 22 and intron 1 inversions was investigated using an inverse and a conventional PCR method, respectively. In patients negative for the inversions, the F8 gene was screened through conformation sensitive gel electrophoresis (CSGE) and further sequencing. The causative mutation was successfully identified in 6/12 patients, including the novel mutation p.G190C. The mothers of these six patients and those of seven other sHA patients molecularly diagnosed in a previous work were investigated for the presence of the genetic alterations found in their sons. All mothers were found to be carriers. This is the first study conducted in Venezuela which directly analyzes the F8 gene in potential carrier mothers to specifically identify the presence of the mutation that was detected in their sons, and complements a previous study on sHA patients. Our findings will facilitate the implementation of regular screening of HA carriers in our country and will allow a better care of bleeding symptoms and genetic counseling.


El diagnóstico molecular de pacientes con hemofilia A (HA) tiene múltiples beneficios, incluyendo la confirmación del diagnóstico y la predicción del riesgo de desarrollar inhibidores. En mujeres portadoras de una mutación, el diagnóstico molecular permite el consejo genético y el diagnóstico prenatal, los cuales son parte de la atención integral de HA en muchos países. Así, el objetivo de este estudio fue determinar mutaciones en el gen F8 en pacientes con HA severa (HAs) y en mujeres portadoras. En 12 pacientes con HAs, la presencia de la inversión del intrón 22 y el intrón 1 fue investigada utilizando una PCR inversa y una convencional, respectivamente. En pacientes negativos para cualquiera de las inversiones, el gen del F8 fue analizado a través de la técnica de electroforesis en gel sensible a conformación (CSGE) y posterior secuenciación. La mutación causante de la enfermedad fue identificada en 6/12 pacientes, incluyendo la mutación nueva p.G190C. Las madres de estos seis pacientes y las de otros siete pacientes de HAs diagnosticados en un estudio previo y fueron investigadas para la presencia de alteraciones genéticas encontradas en sus hijos. Todas las madres resultaron ser portadoras. Éste es el primer estudio realizado en Venezuela donde se analiza directamente el gen F8 en portadoras potenciales para identificar específicamente la presencia de una mutación que fue detectada en sus hijos, y complementa un estudio previo con pacientes HAs. Nuestros hallazgos facilitarán la implementación del análisis regular de portadoras de HA en nuestro país y permitirán un mejor cuidado de los síntomas de sangrado y consejo genético.


Asunto(s)
Humanos , Masculino , Factor VIII/genética , Hemofilia A/genética , Heterocigoto , Mutación , Índice de Severidad de la Enfermedad
7.
Arch. latinoam. nutr ; 66(3): 201-210, Sept. 2016. ilus, tab
Artículo en Español | LILACS, LIVECS | ID: biblio-838446

RESUMEN

El estrés oxidativo constituye un factor importante en el desarrollo de Enfermedades Cardiovasculares (ECVs) debido a los daños graves que provocan las especies reactivas de oxígeno en las biomoléculas, por lo que el consumo adecuado de vitaminas con propiedades antioxidantes podría prevenir o retrasar la aparición de estas enfermedades. El objetivo de este trabajo fue determinar la relación entre la ingesta de antioxidantes, factores nutricionales y marcadores bioquímicos en un grupo de individuos sanos de Caracas, Venezuela. El estudio incluyó 29 participantes entre 18-40 años de edad a los cuales se les realizó tres recordatorios dietéticos de 24h, mediciones antropométricas [peso, estatura, circunferencia de cintura (CC), índice cintura cadera (ICC) y % grasa corporal (% GC)] según normativa del Programa Internacional de Biología (IBP). Adicionalmente, se determinó el perfil lipídico y la concentración de 8-isoprostano como marcador de estrés oxidativo. Los participantes tomaron 1 cápsula diaria de vitaminas antioxidantes por 30 días. Posterior al tratamiento con antioxidante, no hubo cambios significativos en las concentraciones de triglicéridos (TG), colesterol total (CT), colesterol de las lipoproteínas de baja densidad (c-LDL) y colesterol de las lipoproteínas de alta densidad (c-HDL). Por su parte, el 8-isoprostano registró una correlación significativa entre antes y después del tratamiento (r=0,374; p<0,05); siendo el mayor descenso en los individuos que presentaron mayor % GC y CC. Los hallazgos sugieren que el suplemento de antioxidantes tiende a disminuir el estrés oxidativo en un corto período de tiempo, particularmente en individuos con mayor % GC, previniendo el desarrollo de ECVs(AU)


Oxidative stress is an important risk factor for the development of cardiovascular diseases (CVD) due to the serious damage caused by reactive oxygen species to biomolecules, thus, adequate intake of vitamins with antioxidant properties could prevent or delay the onset of these diseases. The aim of this study was to determine the relationship between antioxidant intake, nutritional factors and biochemical markers in a group of healthy individuals in Caracas, Venezuela. The study included 29 participants between 18-40 years of age who underwent three 24-hour dietary recalls, anthropometric measurements [weight, height, waist circumference (WC), waist-hip ratio (WHR) and % body fat (% BF)] according to the International Biology Program (IBP) methodology. In addition, the lipid profile and the concentration of 8-isoprostane as a marker of oxidative stress was determined. The participants took one daily capsule of antioxidant vitamins for 30 days. After treatment with antioxidants, no significant changes in triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDLC) levels were observed. Meanwhile, the 8-isoprostane recorded a significative correlation between before and after treatment (r=0.374; p<0.05). The decline in 8-isoprostane levels was more evident in those individuals with the highest % BF and WC. These findings suggest that antioxidant supplementation decreases oxidative stress in a short period of time, particularly in higher % BF individuals, and might help prevent CVDs(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Enfermedades Cardiovasculares/etiología , Estrés Oxidativo/fisiología , Antioxidantes/administración & dosificación , Vitaminas , Ingestión de Alimentos , Antropometría
8.
Genet Test Mol Biomarkers ; 13(4): 537-42, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19604111

RESUMEN

The most common genetic defect associated with deep vein thrombosis (DVT) is a mutation in the Factor V gene (G1691A), known as Factor V Leiden (FVL). We investigated the genotypes for FVL in 571 individuals in Venezuela: 208 patients with DVT, 175 patients with acute myocardial infarction, 54 patients with stroke, and 134 control subjects. Our results showed in the population analyzed here that the FVL was associated with a fourfold increase in the risk for DVT (odds ratio, 4.24; 95% confidence interval, 1.35-14.79); particularly, women carriers showed a 6.5-fold increase in the risk for DVT. No relation was observed between the presence of FVL and the risk for acute myocardial infarction or stroke. In conclusion, a clear association between the FVL mutation and DVT was observed in the population analyzed in Venezuela. These results are in agreement with those found in other populations with different ethnic backgrounds.


Asunto(s)
Factor V/genética , Infarto del Miocardio/genética , Accidente Cerebrovascular/genética , Trombosis de la Vena/genética , Anciano , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Mutación , Factores de Riesgo , Venezuela
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