Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Biomedica ; 44(2): 191-206, 2024 05 30.
Artículo en Inglés, Español | MEDLINE | ID: mdl-39088535

RESUMEN

Introduction: High-grade gliomas are the most common primary brain tumors in adults, and they usually have a quick fatal course. Average survival is 18 months, mainly, because of tumor resistance to Stupp protocol. Objective: To determine high-grade glioma patient survival and the effect of persuasion variables on survival. Materials and methods: We conducted a longitudinal descriptive study in which 80 untreated recently diagnosed high-grade glioma patients participated. A survey was conducted regarding their exposure to some risk factors, degree of genetic instability in peripheral blood using micronucleus quantification on binuclear lymphocytes, micronuclei in reticulocytes and sister-chromatid exchanges in lymphocytes. In the statistical analysis, this study constructed life tables, used the Kaplan-Meier, and the log-rank test, and in the multivariate analysis, a Cox proportional hazards model was constructed. Results: Eighty patients' clinical, demographic and lifestyle characteristics were analyzed, as well as their survival rates and the average survival time is 784 days (interquartile range: 928). Factors like age, exposure at work to polycyclic hydrocarbons and the number of sister-chromatid exchanges in lymphocytes in the first sampling was significantly survivalrelated in the multivariate analysis. Conclusion: We determined that only three of the analyzed variables have an important effect on survival time when it comes to high-grade glioma patients.


Introducción. Los gliomas de alto grado son los tumores cerebrales primarios más comunes en adultos y, por lo general, tienen un curso mortal rápido. La supervivencia media es de 18 meses, principalmente, como consecuencia de la resistencia del tumor al protocolo Stupp. Objetivo. Determinar la supervivencia de los pacientes con glioma de alto grado y el efecto de las variables de persuasión en la supervivencia. Materiales y métodos. Se llevó a cabo un estudio descriptivo longitudinal en el que participaron 80 pacientes con diagnóstico reciente de glioma de alto grado no tratados. Se hizo una encuesta sobre su exposición a algunos factores de riesgo, grado de inestabilidad genética en sangre periférica mediante cuantificación de micronúcleos en linfocitos binucleares, micronúcleos en reticulocitos e intercambios de cromátidas hermanas en linfocitos. En el análisis estadístico, se construyeron tablas de vida, se utilizó Kaplan-Meier y la prueba de rangos logarítmicos, y en el análisis multivariado, se construyó un modelo de riesgos proporcionales de Cox. Resultados. Se analizaron las características clínicas, demográficas y de estilo de vida de 80 pacientes, así como sus tasas de supervivencia y el tiempo medio de supervivencia fue de 784 días (rango intercuartílico: 928). Factores como la edad, la exposición laboral a hidrocarburos policíclicos y el número de intercambios de cromátidas hermanas en linfocitos en el primer muestreo se relacionaron significativamente con la supervivencia en el análisis multivariante. Conclusión. Según los resultados, el estudio determinó que solo tres de las variables analizadas tienen un efecto importante en el tiempo de supervivencia cuando se trata de pacientes con glioma de alto grado.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Glioma/mortalidad , Glioma/patología , Glioma/genética , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Estudios Longitudinales , Análisis de Supervivencia , Factores de Riesgo , Intercambio de Cromátides Hermanas , Exposición Profesional/efectos adversos , Anciano , Estimación de Kaplan-Meier , Clasificación del Tumor
2.
Med. U.P.B ; 42(2): 52-61, jul.-dic. 2023.
Artículo en Español | LILACS, COLNAL | ID: biblio-1443434

RESUMEN

Durante mucho tiempo, la clasificación de los tumores del sistema nervioso central (SNC) se ha basado en hallazgos histológicos respaldados por pruebas complementarias, como la inmunohistoquímica, establecidas en tejidos. La quinta edición de la clasificación de tumores del SNC de la Organización Mundial de la Salud (OMS), publicada en 2021 (SNC-5) incorpora numerosos marcadores moleculares con utilidad clínico-patológica que son importantes para una clasificación más precisa de las neoplasias del SNC. Ello permiten ayudar a definir los gliomas difusos del adulto, oligodendroglioma mutado para el gen de la IDH (isocitrato deshidrogenasa láctica), con codeleción 1p/19q grados 2 a 3, astrocitoma mutado para IDH sin codeleción 1p/19q, grados 2 a 4 y glioblastoma (GBM) silvestre para IDH. La mediana de sobrevida en los pacientes con GBM es de solo 14.6 meses, debido a la resistencia al protocolo de terapia más utilizado en el mundo, el cual involucra cirugía, radioterapia y quimioterapia con temozolamida (TMZ), un potente alquilante genotóxico. Los criterios de selección del tratamiento y la estimación del pronóstico en pacientes con esta enfermedad son clínico-patológicos. En los últimos años se reportaron numerosas alteraciones moleculares que amplían la comprensión de la biología de estos tumores, pero solo unas pocas influyen como biomarcadores en la toma de decisiones clínicas y del tratamiento. En este artículo se revisan las alteraciones moleculares reportadas para gliomas de alto grado en sangre periférica, también se resalta la importancia de estandarizar nuevos biomarcadores junto a los hallazgos histológicos para mejorar el conocimiento de estos tumores.


For a long time, the classification of central nervous system (CNS) tumors has been based on histological findings supported by complementary tests, such as immunohistochemistry, established in tissues. The fifth edition of the World Health Organization (WHO) Classification of Tumors of the Central Nervous System, published in 2021 (CNS-5), incorporates numerous molecular markers with clinical-pathological utility that are important for a more accurate classification of CNS neoplasms. These markers help to define adult diffuse gliomas, including IDH-mutant oligodendroglioma with 1p/19q codeletion (grades 2-3), IDH-mutant astrocytoma without 1p/19q codeletion (grades 2-4), and wild-type IDH glioblastoma (GBM). The median survival in patients with GBM is only 14.6 months, primarily due to resistance to the most widely used treatment protocol worldwide, which involves surgery, radiotherapy, and chemotherapy with temozolomide (TMZ), a potent genotoxic alkylating agent. The selection criteria for treatment and the estimation of prognosis in patients with this disease are predominantly based on clinical and pathological factors. In recent years, numerous molecular alterations have been reported, expanding our understanding on the biology of these tumors. However, only a few of these molecular alterations serve as biomarkers that influence clinical decision-making and treatment strategies. This article reviews the molecular alterations reported in peripheral blood for high-grade gliomas and emphasizes the importance of standardizing new biomarkers alongside histological findings to enhance our knowledge of these tumors.


Por muito tempo, a classificação dos tumores do sistema nervoso central (SNC) baseou-se em achados histológicos respaldados por exames complementares, como a imuno-histoquímica, estabelecidos nos tecidos. A quinta edição da classificação de tumores do SNC da Organização Mundial da Saúde (OMS), publicada em 2021 (CNS-5), incorpora inúmeros marcadores moleculares com utilidade clinicopatológica importantes para uma classificação mais precisa das neoplasias do SNC. Isso permite definir gliomas difusos adultos, oligodendroglioma mutado para o gene IDH (lactic isocitrato desidrogenase), com codeleção 1p/19q graus 2 a 3, astrocitoma mutado para IDH sem codeleção 1p/19q, graus 2 a 4 e wild- tipo glioblastoma (GBM) para IDH. A sobrevida mediana em pacientes com GBM é de apenas 14,6 meses, devido à resistência ao protocolo terapêutico mais utilizado no mundo, que envolve cirurgia, radioterapia e quimioterapia com temozolamida (TMZ), um potente alquilador genotóxico . Os critérios de seleção para o tratamento e estimativa do prognóstico em pacientes com essa doença são clínico-patológicos. Nos últimos anos, foram relatadas inúmeras alterações moleculares que ampliam o entendimento da biologia desses tumores, mas apenas algumas influenciam na decisão clínica e terapêutica como biomarcadores. Este artigo revisa as alterações moleculares relatadas para gliomas de alto grau no sangue periférico, destacando também a importância da padronização de novos biomarcadores juntamente com os achados histológicos para melhorar o conhecimento desses tumores


Asunto(s)
Humanos
3.
Zookeys ; 1149: 145-169, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250917

RESUMEN

Boana, the third largest genus of Hylinae, has cryptic morphological species. The potential applicability of b-fibrinogen intron 7 - FGBI7 is explored to propose a robust phylogeny of Boana. The phylogenetic potential of FGBI7 was evaluated using maximum parsimony, MrBayes, and maximum likelihood analysis. Comparison of polymorphic sites and topologies obtained with concatenated analysis of FGBI7 and other nuclear genes (CXCR4, CXCR4, RHO, SIAH1, TYR, and 28S) allowed evaluation of the phylogenetic signal of FGBI7. Mean evolutionary rates were calculated using the sequences of the mitochondrial genes ND1 and CYTB available for Boana in GenBank. Dating of Boana and some of its groups was performed using the RelTime method with secondary calibration. FGBI7 analysis revealed high values at informative sites for parsimony. The absolute values of the mean evolutionary rate were higher for mitochondrial genes than for FGBI7. Dating of congruent Boana groups for ND1, CYTB, and FGBI7 revealed closer values between mitochondrial genes and slightly different values from those of FGBI7. Divergence times of basal groups tended to be overestimated when mtDNA was used and were more accurate when nDNA was used. Although there is evidence of phylogenetic potential arising from concatenation of specific genes, FGBI7 provides well-resolved independent gene trees. These results lead to a paradigm for linking data in phylogenomics that focuses on the uniqueness of species histories and ignores the multiplicities of individual gene histories.

4.
PeerJ ; 9: e12427, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34966574

RESUMEN

We assessed how multi- and univariate models reflect marine environmental health based on macrobenthic community responses to three environmental stressor categories: hydrodynamics, organic enrichment and metal contamination. We then compared the models with the benthic index AMBI (AZTI Marine Biotic Index). Macrobenthic community and physicochemical variables were sampled at 35 sites along Babitonga Bay, a subtropical estuary in Southern Brazil. Distance-based linear modelling identified depth, grain size and organic matter as well as Cu and Zn as key stressors affecting the macrobenthos. Using canonical analysis of principal coordinates (CAP), we developed three multivariate models based on the variability in community composition, creating stress gradients. The metal gradient showed better correlation with the benthic community. Sediment quality indices (Geoaccumulation Index and Contamination Factor) showed a low to moderate contamination status, with higher concentrations for Cr, Ni and Zn at the inner areas of the bay. According to AMBI, Babitonga Bay has a "good" environmental health status, and the AMBI values show stronger correlations with the hydrodynamic and organic enrichment gradients (r = 0.50 and r = 0.47) rather than the metal gradient (r = 0.29). Lumbrineridae polychaetes (not included in the AMBI list) and Scoloplos sp. were negatively related to the metal contamination gradient and were considered sensitive, while Sigambra sp., Magelona papillicornis, the gastropod Heleobia australis and species of the crustacean order Mysida were positively related to the gradient and considered tolerant to higher concentrations of metals in the sediment. Despite the inconsistency in the ecological classification provided by AMBI and its relationship with the metal gradient, our results suggest that the environmental quality was satisfactory for the studied gradients. The metal gradient showed the weakest correlation to AMBI. In such cases, the ecological classification of taxa by the index should be evaluated under the perspective of the action of inorganic genotoxic contaminants represented by metals.

5.
Clin Chem Lab Med ; 58(12): 2025-2035, 2020 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-32374276

RESUMEN

Objectives The quantitation of BCR-ABL1 mRNA is mandatory for chronic myeloid leukemia (CML) patients, and RT-qPCR is the most extensively used method in testing laboratories worldwide. Nevertheless, substantial variation in RT-qPCR results makes inter-laboratory comparability hard. To facilitate inter-laboratory comparative assessment, an international scale (IS) for BCR-ABL1 was proposed. Methods The laboratory-specific conversion factor (CF) to the IS can be derived from the World Health Organization (WHO) genetic reference panel; however, this material is limited to the manufacturers to produce and calibrate secondary reference reagents. Therefore, we developed secondary reference calibrators, as lyophilized cellular material, aligned to the IS. Our purpose was both to re-evaluate the CF in 18 previously harmonized laboratories and to propagate the IS to new laboratories. Results Our field trial including 30 laboratories across Latin America showed that, after correction of raw BCR-ABL1/ABL1 ratios using CF, the relative mean bias was significantly reduced. We also performed a follow-up of participating laboratories by annually revalidating the process; our results support the need for continuous revalidation of CFs. All participating laboratories also received a calibrator to determine the limit of quantification (LOQ); 90% of them could reproducibly detect BCR-ABL1, indicating that these laboratories can report a consistent deep molecular response. In addition, aiming to investigate the variability of BCR-ABL1 measurements across different RNA inputs, we calculated PCR efficiency for each individual assay by using different amounts of RNA. Conclusions In conclusion, for the first time in Latin America, we have successfully organized a harmonization platform for BCR-ABL1 measurement that could be of immediate clinical benefit for monitoring the molecular response of patients in low-resource regions.


Asunto(s)
Proteínas de Fusión bcr-abl/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Calibración , Humanos , América Latina , Control de Calidad , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estándares de Referencia , Reproducibilidad de los Resultados
6.
Vitae (Medellín) ; 26(1): 23-43, 2019. Ilustraciones
Artículo en Inglés | LILACS, COLNAL | ID: biblio-995583

RESUMEN

Background: Breast cancer is the second cause of death in women in developed and undeveloped countries, including Colombia. A high percentage of these tumors is estrogen dependent, for which the hormonal treatment is the most used therapy in breast cancer. Currently, the first line treatment for breast tumor in postmenopausal women is the letrozole, an aromatase enzyme inhibitor that avoids the transformation of androgens to estrogens. Since letrozole produced adverse effects on patients, there is a requirement for new alternative treatments. Furthermore, omega fatty acids (ω-FA), essential as they are obtained from the normal diet or from dietary supplements, have demonstrated nutraceutical potential because of their anti-inflammatory or pro-inflammatory activity. Nonetheless, there is controversy in in vitro, in vivo and epidemiologic reports regarding their preventive or inducing activities of carcinogenesis in animals and humans, depending on the structure of the ω-FA. Objectives: This review aims to show the main in vitro, in vivo and epidemiologic evidences of the chemotherapeutic potential of ω-3 and ω-6 FA in different types of neoplasm, particularly in breast cancer, in individual or combined treatments with diverse antineoplastics. Methods: PubMed and Science Direct databases revealed the most representative studies, published during the last two decades, about ω-3 and ω-6 FA, breast cancer and the principal therapeutic strategies for this neoplasm. Findings were presented in separated topics to provide an overview of ω-FA and their potential in treatments for breast cancer. Results: Patients treated with estrogens and progesterone derivate have shown predisposition to develop breast cancer after two years of continued therapy. Furthermore, ω-FA with known nutraceutical potential have demonstrated their potential as adjuvants in the treatment against different neoplasms, like hepatic and colon cancer. Conclusions: Current therapies for breast cancer and their low efficacy in the long term led to explore new alternative treatments with ω-FA. These essential fatty acids in daily consumption could enhance the antineoplastic agent effect. Nevertheless, metabolism of the ω-FA must be considered for this use.


Antecedentes: el cáncer de mama es la segunda causa de muerte de mujeres en países desarrollados y no desarrollados, incluido Colombia. La mayoría de estos tumores son dependientes de estrógeno por esa razón, la terapia más utilizada es la hormonal. Actualmente, el tratamiento de primera línea en mujeres posmenopáusicas es el letrozol, inhibidor de la enzima aromatasa, que evita la conversión de andrógenos en estrógenos. El letrozol causa efectos adversos en las pacientes, lo cual motiva la búsqueda de nuevas alternativas que disminuyan estos efectos. Los ácidos grasos omega, esenciales en la dieta regular o suplementaria, han mostrado su potencial nutracéutico ambivalente, como antiinflamatorios o proinflamatorios. Debido a esto, existe controversia en distintos reportes a nivel in vitro, in vivo y epidemiológicos sobre la actividad preventiva o quimioterapéutica de los ω-3 y ω-6 AGOs. Objetivos: el aporte de este artículo, es mostrar las principales evidencias in vitro, in vivo y epidemiológicas del potencial quimioterapéutico de los AGOs en tratamientos individuales y combinados con antineoplásicos, en distintos tipos de cánceres, particularmente en el cáncer de mama. Métodos: se revisaron las bases de datos PubMed y Science Direct y se seleccionaron los estudios más representativos de las dos últimas décadas sobre ω-3 y ω-6 AGOs y las principales estrategias usadas en el cáncer de mama. Los hallazgos se presentan en temas separados, primero una visión general de los AGOs y luego su potencial bioactivo en tratamientos contra el cáncer de mama. Resultados: la mayoría de los estudios en pacientes con cáncer de mama, tratadas con estrógenos y derivados de progesterona, han mostrado predisposición a desarrollar cáncer de mama después de dos años de terapia continua. De otro lado, los AGOs han demostrado su potencial como adyuvantes en el tratamiento en diferentes cánceres como el de colon y hepático. Conclusiones: las terapias actuales para el cáncer de mama y su baja eficacia a largo plazo exigen explorar nuevas alternativas de terapias, que incluyen los AGOs podrían potenciar fármacos, no obstante, es necesario tener en cuenta, el metabolismo de los AGOs, para uso


Asunto(s)
Humanos , Neoplasias de la Mama , Aceites de Pescado , Estrógenos , Ácidos Grasos Insaturados , Antiinflamatorios
7.
Biomedica ; 38(3): 379-387, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30335243

RESUMEN

Introduction: The quantification of chromosomal instability is an important parameter to assess genotoxicity and radiosensitivity. Most conventional techniques require cell cultures or laborious microscopic analyses of chromosomes or nuclei. However, a flow cytometry that selects the reticulocytes has been developed as an alternative for in vivo studies, which expedites the analytical procedures and increases up to 20 times the number of target cells to be analyzed. Objectives: To standardize the flow cytometry parameters for selecting and quantifying the micronucleated reticulocytesCD71+ (MN-RET) from freshly drawn peripheral blood and to quantify the frequency of this abnormal cell subpopulation as a measure of cytogenetic instability in populations of healthy volunteers (n =25), and patients (n=25), recently diagnosed with high-grade gliomas before the onset of treatment. Materials and methods: Blood cells were methanol-fixed and labeled with anti-CD-71-PE for reticulocytes, antiCD-61-FITC for platelet exclusion, and propidium iodide for DNA detection in reticulocytes. The MN-RETCD71+ cell fraction was selected and quantified with an automatic flow cytometer. Results: The standardization of cytometry parameters was described in detail, emphasizing the selection and quantification of the MN-RETCD71+ cellular fraction. The micronuclei basal level was established in healthy controls. In patients, a 5.2-fold increase before the onset of treatment was observed (p <0.05). Conclusion: The data showed the usefulness of flow cytometry coupled with anti-CD-71-PE and anti-CD-61-FITC labeling in circulating reticulocytes as an efficient and high resolution method to quantify chromosome instability in vivo. Finally, possible reasons for the higher average of micronuclei in RETCD71+ cells from untreated high-grade glioma patients were discussed.


Asunto(s)
Inestabilidad Cromosómica , Citometría de Flujo/métodos , Glioblastoma/genética , Micronúcleos con Defecto Cromosómico , Reticulocitos/patología , Separación Celular/métodos , Femenino , Glioblastoma/sangre , Glioblastoma/patología , Humanos , Masculino , Clasificación del Tumor , Factores de Riesgo , Manejo de Especímenes/métodos
8.
Biomédica (Bogotá) ; 38(3): 378-387, jul.-set. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-973991

RESUMEN

Resumen Introducción. La cuantificación de la inestabilidad cromosómica es un parámetro importante para evaluar la genotoxicidad y la radiosensibilidad. Las técnicas convencionales requieren cultivos celulares o laboriosos análisis microscópicos de cromosomas o núcleos. La citometría de flujo en reticulocitos ha surgido como una alternativa para los estudios in vivo, ya que reduce los tiempos de análisis e incrementa hasta en 20 veces el número de células analizables. Objetivos. Estandarizar los parámetros de citometría de flujo requeridos para seleccionar y cuantificar reticulocitos micronucleados (RET-MN) a partir de muestras de sangre periférica, y cuantificar la frecuencia de esta subpoblación anormal como medida de inestabilidad citogenética en sendas poblaciones de voluntarios sanos (n=25) y pacientes (n=25) recién diagnosticados con gliomas de alto grado antes de iniciar el tratamiento. Materiales y métodos. Las células sanguíneas se marcaron con anti-CD71-PE para reticulocitos, anti- CD61-FITC para la exclusión de plaquetas y yoduro de propidio para detectar el ADN en reticulocitos. La fracción celular MN-RETCD71+ se seleccionó y se cuantificó con un citómetro de flujo automático. Resultados. Se describió detalladamente la estandarización de los parámetros citométricos, con énfasis en la selección y la cuantificación de la subpoblación celular MN-RETCD71+. Se establecieron los niveles basales de MN-RETCD71+ en la población de control y en los pacientes se encontró un incremento de 5,2 veces antes de iniciar el tratamiento (p<0,05). Conclusión. Los resultados evidenciaron la utilidad de la citometría de flujo acoplada a la marcación de las células RETCD71+ como método eficiente para cuantificar la inestabilidad cromosómica in vivo. Se sugieren posibles razones del incremento de micronúcleos en células RETCD71+ de pacientes con gliomas.


Abstract Introduction: The quantification of chromosomal instability is an important parameter to assess genotoxicity and radiosensitivity. Most conventional techniques require cell cultures or laborious microscopic analyses of chromosomes or nuclei. However, a flow cytometry that selects the reticulocytes has been developed as an alternative for in vivo studies, which expedites the analytical procedures and increases up to 20 times the number of target cells to be analyzed. Objectives: To standardize the flow cytometry parameters for selecting and quantifying the micronucleated reticulocytesCD71+ (MN-RET) from freshly drawn peripheral blood and to quantify the frequency of this abnormal cell subpopulation as a measure of cytogenetic instability in populations of healthy volunteers (n =25), and patients (n=25), recently diagnosed with high-grade gliomas before the onset of treatment. Materials and methods: Blood cells were methanol-fixed and labeled with anti-CD-71-PE for reticulocytes, antiCD-61-FITC for platelet exclusion, and propidium iodide for DNA detection in reticulocytes. The MN-RETCD71+ cell fraction was selected and quantified with an automatic flow cytometer. Results: The standardization of cytometry parameters was described in detail, emphasizing the selection and quantification of the MN-RETCD71+ cellular fraction. The micronuclei basal level was established in healthy controls. In patients, a 5.2-fold increase before the onset of treatment was observed (p <0.05). Conclusion: The data showed the usefulness of flow cytometry coupled with anti-CD-71-PE and anti- CD-61-FITC labeling in circulating reticulocytes as an efficient and high resolution method to quantify chromosome instability in vivo. Finally, possible reasons for the higher average of micronuclei in RETCD71+ cells from untreated high-grade glioma patients were discussed.


Asunto(s)
Femenino , Humanos , Masculino , Reticulocitos/patología , Glioblastoma/genética , Inestabilidad Cromosómica , Micronúcleos con Defecto Cromosómico , Citometría de Flujo/métodos , Manejo de Especímenes/métodos , Separación Celular/métodos , Factores de Riesgo , Glioblastoma/sangre , Glioblastoma/patología , Clasificación del Tumor
9.
Artículo en Inglés | MEDLINE | ID: mdl-29963012

RESUMEN

Temozolomide, an alkylating agent, initially used in the treatment of gliomas was expanded to include pituitary tumors in 2006. After 12 years of use, temozolomide has shown a notable advancement in pituitary tumor treatment with a remarkable improvement rate in the 5-year overall survival and 5-year progression-free survival in both aggressive pituitary adenomas and pituitary carcinomas. In this paper, we review the mechanism of action of temozolomide as alkylating agent, its interaction with deoxyribonucleic acid repair systems, therapeutic effects in pituitary tumors, unresolved issues, and future directions relating to new possibilities of targeted therapy.

10.
Ann Hepatol ; 17(3): 444-460, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29735783

RESUMEN

INTRODUCTION AND AIM: Epigenetic alterations play an essential role in cancer onset and progression, thus studies of drugs targeting the epigenetic machinery are a principal concern for cancer treatment. Here, we evaluated the potential of the combination of the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5aza-dC) and the pan-deacetylase inhibitor Trichostatin A (TSA), at low cytotoxic concentrations, to modulate the canonical Wnt/ß-catenin pathway in liver cancer cells. MATERIAL AND METHODS: Pyrosequencing was used for DNA methylation analyses of LINE-1 sequences and the Wnt/ß-catenin pathway antagonist DKK3, SFRP1, WIF1 and CDH1. qRT-PCR was employed to verify the expression of the antagonist. Pathway regulation were evaluated looking at the expression of ß-catenin and E-cadherin by confocal microscopy and the antitumoral effects of the drugs was studied by wound healing and clonogenic assays. RESULTS: Our result suggest that 5aza-dC and TSA treatments were enough to induce a significant expression of the pathway antagonists, decrease of ß-catenin protein levels, re-localization of the protein to the plasma membrane, and pathway transcriptional activity reduction. These important effects exerted an antitumoral outcome shown by the reduction of the migration and clonogenic capabilities of the cells. CONCLUSION: We were able to demonstrate Wnt/ ß-catenin pathway modulation through E-cadherin up-regulation induced by 5aza-dC and TSA treatments, under an activation-pathway background, like CTNNB1 and TP53 mutations. These findings provide evidences of the potential effect of epigenetic modifier drugs for liver cancer treatment. However, further research needs to be conducted, to determine the in vivo potential of this treatment regimen for the management of liver cancer.


Asunto(s)
Antígenos CD/metabolismo , Antimetabolitos Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Cadherinas/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Decitabina/farmacología , Epigénesis Genética/efectos de los fármacos , Ácidos Hidroxámicos/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Antígenos CD/genética , Cadherinas/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Proliferación Celular/genética , Metilasas de Modificación del ADN/antagonistas & inhibidores , Metilasas de Modificación del ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Mutación , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt/efectos de los fármacos , Vía de Señalización Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
11.
BMC Genomics ; 19(1): 10, 2018 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-29298677

RESUMEN

BACKGROUND: In recent years, the idea of a highly immunogenic protein-based vaccine to combat Streptococcus pneumoniae and its severe invasive infectious diseases has gained considerable interest. However, the target proteins to be included in a vaccine formulation have to accomplish several genetic and immunological characteristics, (such as conservation, distribution, immunogenicity and protective effect), in order to ensure its suitability and effectiveness. This study aimed to get comprehensive insights into the genomic organization, population distribution and genetic conservation of all pneumococcal surface-exposed proteins, genetic regulators and other virulence factors, whose important function and role in pathogenesis has been demonstrated or hypothesized. RESULTS: After retrieving the complete set of DNA and protein sequences reported in the databases GenBank, KEGG, VFDB, P2CS and Uniprot for pneumococcal strains whose genomes have been fully sequenced and annotated, a comprehensive bioinformatic analysis and systematic comparison has been performed for each virulence factor, stand-alone regulator and two-component regulatory system (TCS) encoded in the pan-genome of S. pneumoniae. A total of 25 S. pneumoniae strains, representing different pneumococcal phylogenetic lineages and serotypes, were considered. A set of 92 different genes and proteins were identified, classified and studied to construct a pan-genomic variability map (variome) for S. pneumoniae. Both, pneumococcal virulence factors and regulatory genes, were well-distributed in the pneumococcal genome and exhibited a conserved feature of genome organization, where replication and transcription are co-oriented. The analysis of the population distribution for each gene and protein showed that 49 of them are part of the core genome in pneumococci, while 43 belong to the accessory-genome. Estimating the genetic variability revealed that pneumolysin, enolase and Usp45 (SP_2216 in S. p. TIGR4) are the pneumococcal virulence factors with the highest conservation, while TCS08, TCS05, and TCS02 represent the most conserved pneumococcal genetic regulators. CONCLUSIONS: The results identified well-distributed and highly conserved pneumococcal virulence factors as well as regulators, representing promising candidates for a new generation of serotype-independent protein-based vaccine(s) to combat pneumococcal infections.


Asunto(s)
Variación Genética , Streptococcus pneumoniae/genética , Factores de Virulencia/genética , Proteínas Bacterianas/genética , Mapeo Cromosómico , Genes Bacterianos , Genes Reguladores , Genoma Bacteriano , Filogenia , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/patogenicidad
12.
Curr Opin Toxicol ; 7: 9-16, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29159324

RESUMEN

Reactive oxygen and nitrogen species damage cellular macromolecules including DNA. Cells have a robust base excision repair pathway to deal with this damage in both nuclear and mitochondrial genomes. However, mitochondria lack nucleotide excision repair. Evidence suggests that chronic oxidative stress can induce protective pathways lowering genotoxicity. Understanding oxidant injury to DNA and its repair is critical for our understanding the pathophysiology of a wide range of human disorders.

13.
Mar Pollut Bull ; 125(1-2): 66-76, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28789782

RESUMEN

Changes in the structure of benthic macrofauna and its relationship with hydrocarbon contamination were determined at different spatial scales in sublittoral sediments of two large estuaries in Brazil. Guanabara Bay (GB) is a heavily polluted estuary due to the presence of a large industrial complex and high demographic density. Laranjeiras Bay (LB) lies in an Environmental Protection Area and can still be considered as preserved from human activities. Despite some spatial differences within each bay, the PAHs concentrations were significantly and consistently higher in GB, with values generally above the threshold effect levels. No signs of hydrocarbon contamination were observed in LB. Macrofauna abundance, diversity and overall assemblage structure were largely different between bays. Canonical analysis of principal coordinates (CAP), used to model the relationship between macrofauna and PAHs levels, indicated that this class of hydrocarbons is the main structuring factor of soft-bottom assemblages in both bays.


Asunto(s)
Biodiversidad , Contaminación Ambiental/efectos adversos , Invertebrados , Hidrocarburos Policíclicos Aromáticos/toxicidad , Animales , Bahías/análisis , Brasil , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Estuarios , Gastrópodos , Sedimentos Geológicos/análisis , Hidrocarburos/análisis , Oligoquetos , Contaminación por Petróleo , Poliquetos , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis
14.
Coluna/Columna ; 16(2): 153-158, Apr.-June 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1039639

RESUMEN

ABSTRACT Objective: The difficulties of the study and the lumbago approach stem from several factors, among them, the lack of a reliable correlation between the clinical findings and image results and the fact the lumbar segment is innervated by a network of diffuse and intertwined nerves, making it difficult to accurately determine the location of pain origin. The treatment of this disease is mainly based on conservative measures (rest, analgesia, physical therapy) and only in a few cases, the option is surgical measures. Methods: In this study, we conducted an analysis of the results obtained with foraminal, sacral and facet infiltrations of corticoids in the lumbosacral spine in a period of three months in 83 patients with low back pain. Results: The patients showed a statistically significant reduction of pain (mean value) after infiltrations (sacral, foraminal and facet), according to the Visual Analogue Scale of 4 points in the immediate postoperative period, reduction of 3.9 points at 15 days, reduction of 3.5 points at 30 days, a reduction of 3.1 points at 45 days and a reduction of 2.7 points at 90 days. Conclusion: The sacral, foraminal and facet infiltrations of corticoids to control low back pain relieves short-term pain (30 days) and medium and long-term (30-90 days), when the indication is correct.


RESUMO Objetivo: As dificuldades do estudo e da abordagem das lombalgias decorrem de vários fatores, entre eles, inexistência de correlação fidedigna entre os achados clínicos e os de imagem e o fato de o segmento lombar ser inervado por uma rede de nervos difusa e entrelaçada, que torna difícil determinar com precisão o local de origem da dor. O tratamento dessa doença é principalmente baseado em medidas conservadoras (repouso, analgesia, fisioterapia) e em poucos casos, a opção é recorrer a medidas cirúrgicas. Métodos: No presente estudo, realizamos uma análise dos resultados obtidos com infiltrações foraminais, sacrais e facetárias com corticoides na coluna lombossacral em um prazo de 3 meses, em 83 pacientes com lombalgias. Resultados: Os pacientes apresentaram redução estatisticamente significante da dor (valor da média) depois das infiltrações (sacrais, foraminais e facetárias), segundo a Escala Visual Analógica de 4 pontos no pós-operatório imediato, redução de 3,9 pontos aos 15 dias, redução de 3,5 pontos aos 30 dias, redução de 3,1 pontos aos 45 dias e redução de 2,7 pontos aos 90 dias. Conclusão: As infiltrações sacrais, foraminais e facetárias de corticoides para controle das lombalgias alivia a dor a curto (30 dias), médio e longo prazo (30 a 90 dias), quando são indicadas corretamente.


RESUMEN Objetivo: Las dificultades del estudio y del abordaje de la lumbalgia se derivan de varios factores, entre ellos, no hay correlación fiable entre los hallazgos clínicos y los encontrados en las imágenes, además del hecho que el segmento lumbar está inervado por una red de nervios difusos y entrelazados lo que dificulta determinar la ubicación precisa de origen del dolor. El tratamiento de esta enfermedad se basa principalmente en medidas conservadoras (reposo, analgesia, terapia física) y en unos pocos, la opción es quirúrgica. Métodos: En el presente estudio, se realizó un análisis de los resultados obtenidos con infiltraciones foraminales, sacrales y facetarias en la columna lumbosacra, en un período de tres meses en 83 pacientes con dolor lumbar. Resultados: Los pacientes mostraron una reducción estadísticamente significativa en el dolor (valor medio) después de las infiltraciones (sacral, foraminal y facetaria), de acuerdo con la Escala Visual Analógica de 4 puntos en el postoperatorio inmediato, reducción de 3,9 puntos en 15 días, reducción de 3,5 puntos a los 30 días, una reducción de 3,1 puntos en 45 días y una reducción de 2,7 puntos en 90 días. Conclusión: Las infiltraciones sacrales, foraminales y facetarias de corticosteroides para controlar la lumbalgia alivia el dolor a corto (30 días), mediano y largo plazo (30 a 90 días), cuando se hayan indicado correctamente.


Asunto(s)
Humanos , Analgesia Epidural , Dolor de la Región Lumbar , Corticoesteroides
15.
Cir Cir ; 85(6): 459-470, 2017.
Artículo en Español | MEDLINE | ID: mdl-28063606

RESUMEN

BACKGROUND: Improper use of antibiotics increases antimicrobial resistance. OBJECTIVE: Evaluate the use of antibiotics and the impact of an intervention designed to improve antibiotic prescription for surgical prophylaxis in 6 hospitals of Monterrey, Mexico. MATERIAL AND METHODS: Design: A prospective multicenter survey and a pretest-postest experimental study. Phase 1: Survey to evaluate the use of antibiotics through an especially designed guide. Phase 2: Intervention designed to improve antibiotic prescription for surgical prophylaxis by the medical staff by using printed, audiovisual and electronic messages. Phase 3: Survey to evaluate the impact of the intervention. ANALYSIS: Frequencies, percentages, medians, ranges and X2 test. RESULTS: Phase 1: We evaluated 358 surgical patients, 274 prophylactic antibiotic regimens. A total of 96% of antibiotics regimens began with inappropriate timing (290/302), 82.8% were inappropriate regimens (274/331), 77.7% were in inappropriate dosage (230/296), 86% of inadequate length (241/280), and in 17.4% restricted antibiotics were used (52/299). Phase 2: 9 sessions including 189 physicians (14 department chairs, 58 general practitioners and 117 residents). Phase 3: We evaluated 303 surgical patients, 218 prophylactic antibiotics regimens. Inappropriate treatment commencement was reduced to 84.1% (180/214) (P<0.001), inappropriate regimens to 75.3% (162/215) (P=0.03), inappropriate dosages to 51.2% (110/215) (P<0.001), and use of restricted antibiotics to 8.3% (18/215) (P=0.003). CONCLUSIONS: Inappropriate use of prophylactic antibiotics in surgery is a frequent problem in Monterrey. The intervention improved the antibiotic prescription for surgical prophylaxis by reducing inappropriate treatment commencement, regimens, dosages, and overuse of restricted antibiotics. It is necessary to strengthen strategies to improve the prescription of antibiotics in surgical prophylaxis.


Asunto(s)
Profilaxis Antibiótica , Programas de Optimización del Uso de los Antimicrobianos/organización & administración , Prescripción Inadecuada/prevención & control , Pautas de la Práctica en Medicina/estadística & datos numéricos , Cuidados Preoperatorios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Niño , Preescolar , Prescripciones de Medicamentos/estadística & datos numéricos , Utilización de Medicamentos , Femenino , Hospitales Urbanos , Humanos , Prescripción Inadecuada/estadística & datos numéricos , Lactante , Recién Nacido , Masculino , México , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Evaluación de Programas y Proyectos de Salud , Estudios Prospectivos , Infección de la Herida Quirúrgica/prevención & control , Adulto Joven
16.
Redox Biol ; 9: 124-133, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27479053

RESUMEN

Many environmental and physiological stresses are chronic. Thus, cells are constantly exposed to diverse types of genotoxic insults that challenge genome stability, including those that induce oxidative DNA damage. However, most in vitro studies that model cellular response to oxidative stressors employ short exposures and/or acute stress models. In this study, we tested the hypothesis that chronic and repeated exposure to a micromolar concentration of hydrogen peroxide (H2O2) could activate DNA damage responses, resulting in cellular adaptations. For this purpose, we developed an in vitro model in which we incubated mouse myoblast cells with a steady concentration of ~50µM H2O2 for one hour daily for seven days, followed by a final challenge of a 10 or 20X higher dose of H2O2 (0.5 or 1mM). We report that intermittent long-term exposure to this oxidative stimulus nearly eliminated cell toxicity and significantly decreased genotoxicity (in particular, a >5-fold decreased in double-strand breaks) resulting from subsequent acute exposure to oxidative stress. This protection was associated with cell cycle arrest in G2/M and induction of expression of nine DNA repair genes. Together, this evidence supports an adaptive response to chronic, low-level oxidative stress that results in genomic protection and up-regulated maintenance of cellular homeostasis.


Asunto(s)
Adaptación Biológica/genética , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/genética , Reparación del ADN/efectos de los fármacos , Reparación del ADN/genética , Regulación de la Expresión Génica/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Animales , Línea Celular , Daño del ADN , Ratones , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Oxidantes/metabolismo , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Especies Reactivas de Oxígeno/metabolismo
17.
Rev. chil. obstet. ginecol ; 80(6): 486-492, dic. 2015.
Artículo en Español | LILACS | ID: lil-771637

RESUMEN

En los organismos vivos, las cantidades de radicales libres y especies reactivas del oxígeno (ROS) son controladas por un complejo sistema de homeostasis, capaz de mantener niveles fisiológicos de ROS necesarios para el funcionamiento y regulación de algunas biomoléculas. Paralelamente, los organismos poseen sistemas bioquímicos de protección contra el estrés oxidativo, que consiste en el desbalance entre la producción de especies químicas altamente reactivas y las defensas antioxidantes de la célula. Dicho estrés contribuye de manera importante a la etiología tanto de la senescencia celular como de algunas enfermedades. En el contexto reproductivo, las células espermáticas pasan por una serie de cambios fisiológicos durante los procesos de maduración, capacitación y fecundados, entre los que se incluyen las modificaciones de las proteínas existentes, reguladas por señales procedentes del entorno espermático, donde las ROS modulan importantes vías bioquímicas, involucradas en procesos fundamentales de la función del espermatozoide y que se pueden alterar en estados de estrés oxidativo. El objetivo de esta revisión de literatura es describir algunos de los procesos que contribuyen al estrés oxidativo y sus implicaciones sobre la funcionalidad espermática.


Living organisms regulate the load of free radicals and reactive oxygen species (ROS) by a complex homeostatic system, capable of maintaining physiological levels of ROS, necessary for the action and regulation of some biomolecules. In parallel, organisms harbor biochemical protection systems against oxidative stress, consisting of an unbalance state between oxygen reactive chemical species and antioxidant defense production; this kind of biochemical stress has been shown to contribute to cellular senescence and the development of different diseases. In the reproductive field, the spermatic cells undergo a serial of physiological changes during the maturation, capacitation and fertilization process. Such changes include the modification of proteins regulated by signals from the sperm environment, where ROS modulate important biochemical pathways involved in fundamental processes of sperm function, and that could be altered under oxidative stress conditions. The objective of this review is to describe some of the processes that contribute to oxidative stress and its implications on sperm functionality.


Asunto(s)
Humanos , Masculino , Espermatozoides/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo , Espermatozoides/citología , Fertilidad , Radicales Libres/metabolismo , Antioxidantes/metabolismo
18.
Reprod Biol Endocrinol ; 13: 47, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25994017

RESUMEN

BACKGROUND: Several factors have been shown to influence semen parameters, one of which is sexual abstinence; a clinical criteria included in the semen evaluation to provide maximum sperm quality. The aim of the present study was to assess the effect of a daily ejaculation frequency on conventional and functional semen parameters. METHODS: Semen samples were collected daily over a period of two weeks of which every second sample per person was processed and analyzed according to the World Health Organization guidelines. Furthermore, mitochondrial function, intracellular reactive oxygen species production and sperm DNA fragmentation were evaluated by flow cytometry. RESULTS: Total sperm count and seminal volume per ejaculation declined and remained decreased for the duration of the daily ejaculation period. However, conventional parameters such as sperm concentration, motility, progressive motility, morphology, vitality and functional parameters such as sperm plasma membrane integrity, mitochondrial membrane potential and DNA fragmentation was not significantly affected and remained similar to the initial measurement throughout the daily ejaculation period. Despite intra- and inter individual variations, the average values of the basic semen parameters remained above the WHO (2010) reference values throughout the daily ejaculation period. Interestingly, a decreasing trend in intracellular ROS production was observed, although statistically not significant. CONCLUSIONS: The study shows that an extended 2 week period of daily ejaculation does not have major clinical effects on conventional and functional seminal parameters.


Asunto(s)
Eyaculación , Análisis de Semen , Fragmentación del ADN , Fertilidad , Citometría de Flujo , Humanos , Masculino , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , Mitocondrias/fisiología , Especies Reactivas de Oxígeno , Valores de Referencia , Abstinencia Sexual , Recuento de Espermatozoides , Motilidad Espermática , Factores de Tiempo , Organización Mundial de la Salud
19.
Mar Pollut Bull ; 91(2): 454-60, 2015 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-25455787

RESUMEN

Indices based on macrobenthic responses to disturbance remain to be adequately tested for the detection of spatial variability by robust sampling designs. We present herein a congruence test to real-world data of the widely used indices AMBI, M-AMBI and BENTIX in tidal flats of a subtropical estuary. We used a hierarchical sampling design to evaluate the spatial variability of the indices in response to distinct levels of sewage contamination. Indices were then tested for correlations with chemical proxies of contamination and for the similarity of responses. BENTIX and M-AMBI produced over- and underestimations of ecological status. We found a low degree of similarity among indices as an expression of the spatial variation of macrofaunal assemblages on their performances. Only AMBI varied at the contamination scale (10(3)m) and was congruent with physical-chemical proxies. Ambiguous responses indicated effects of natural inputs of organic matter rather than environmental quality associated to sewage.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/métodos , Estuarios , Invertebrados/fisiología , Aguas del Alcantarillado , Contaminación del Agua/análisis , Animales , Brasil , Monitoreo del Ambiente/normas , Análisis Espacial
20.
Database (Oxford) ; 2014: bau002, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24573879

RESUMEN

Networks can greatly advance data sharing attitudes by providing organized and useful data sets on marine biodiversity in a friendly and shared scientific environment. NONATObase, the interactive database on polychaetes presented herein, will provide new macroecological and taxonomic insights of the Southwestern Atlantic region. The database was developed by the NONATO network, a team of South American researchers, who integrated available information on polychaetes from between 5°N and 80°S in the Atlantic Ocean and near the Antarctic. The guiding principle of the database is to keep free and open access to data based on partnerships. Its architecture consists of a relational database integrated in the MySQL and PHP framework. Its web application allows access to the data from three different directions: species (qualitative data), abundance (quantitative data) and data set (reference data). The database has built-in functionality, such as the filter of data on user-defined taxonomic levels, characteristics of site, sample, sampler, and mesh size used. Considering that there are still many taxonomic issues related to poorly known regional fauna, a scientific committee was created to work out consistent solutions to current misidentifications and equivocal taxonomy status of some species. Expertise from this committee will be incorporated by NONATObase continually. The use of quantitative data was possible by standardization of a sample unit. All data, maps of distribution and references from a data set or a specified query can be visualized and exported to a commonly used data format in statistical analysis or reference manager software. The NONATO network has initialized with NONATObase, a valuable resource for marine ecologists and taxonomists. The database is expected to grow in functionality as it comes in useful, particularly regarding the challenges of dealing with molecular genetic data and tools to assess the effects of global environment change. Database URL: http://nonatobase.ufsc.br/.


Asunto(s)
Bases de Datos Genéticas , Poliquetos/genética , Programas Informáticos , Animales , Océano Atlántico , Geografía , Motor de Búsqueda , Especificidad de la Especie
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA