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1.
Reprod Biomed Online ; 29(5): 627-33, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25246117

RESUMEN

BMP15 has drawn particular attention in the pathophysiology of reproduction, as its mutations in mammalian species have been related to different reproductive phenotypes. In humans, BMP15 coding regions have been sequenced in large panels of women with premature ovarian failure (POF), but only some mutations have been definitely validated as causing the phenotype. A functional association between the BMP15 c.-9C>G promoter polymorphism and cause of POF have been reported. The aim of this study was to determine the potential functional effect of this sequence variant on specific BMP15 promoter transactivation disturbances. Bioinformatics was used to identify transcription factor binding sites located on the promoter region of BMP15. Reverse transcription polymerase chain reaction was used to study specific gene expression in ovarian tissue. Luciferase reporter assays were used to establish transactivation disturbances caused by the BMP15 c.-9C>G variant. The c.-9C>G variant was found to modify the PITX1 transcription factor binding site. PITX1 and BMP15 co-expressed in human and mouse ovarian tissue, and PITX1 transactivated both BMP15 promoter versions (-9C and -9G). It was found that the BMP15 c.-9G allele was related to BMP15 increased transcription, supporting c.-9C>G as a causal agent of POF.


Asunto(s)
Proteína Morfogenética Ósea 15/genética , Ovario/metabolismo , Polimorfismo de Nucleótido Simple , Insuficiencia Ovárica Primaria/genética , Regiones Promotoras Genéticas , Alelos , Animales , Sitios de Unión , Células COS , Chlorocebus aethiops , Biología Computacional , Femenino , Variación Genética , Humanos , Luciferasas/metabolismo , Ratones , Mutación , Factores de Transcripción Paired Box/metabolismo , Fenotipo , Transcripción Genética , Activación Transcripcional
2.
Eur Respir Rev ; 23(131): 118-30, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24591669

RESUMEN

Airway remodelling is a critical feature of chronic bronchial diseases, characterised by aberrant repair of the epithelium and accumulation of fibroblasts, which contribute to extracellular matrix (ECM) deposition resulting in fixed bronchial obstruction. Recently, epithelial-mesenchymal transition (EMT) has been identified as a new source of fibroblasts that could contribute to the remodelling of the airways. This phenomenon consists of the loss of the epithelial phenotype by bronchial epithelial cells and the acquisition of a mesenchymal phenotype. These cells are then able to migrate and secrete ECM molecules. Herein, we review the different types of EMT. We will then focus on the signalling pathways that are involved, such as transforming growth factor-ß and Wnt, as well as the more recently described Sonic Hedgehog pathway. Finally, we will highlight the implication of EMT in airway remodelling in specific chronic bronchial pathologies, such as asthma, chronic obstructive pulmonary disease and bronchiolitis obliterans following lung transplantation. Despite the limitations of in vitro models, future studies of EMT in vivo are warranted to shed new light on the pathomechanisms of bronchial obstruction.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias) , Bronquios/patología , Enfermedades Bronquiales/patología , Transición Epitelial-Mesenquimal , Fibroblastos/patología , Animales , Bronquios/metabolismo , Bronquios/fisiopatología , Enfermedades Bronquiales/metabolismo , Enfermedades Bronquiales/fisiopatología , Enfermedad Crónica , Fibroblastos/metabolismo , Humanos , Pronóstico , Transducción de Señal
3.
PLoS One ; 8(6): e64692, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23755135

RESUMEN

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by extreme sensitivity to actinic pigmentation changes in the skin and increased incidence of skin cancer. In some cases, patients are affected by neurological alterations. XP is caused by mutations in 8 distinct genes (XPA through XPG and XPV). The XP-V (variant) subtype of the disease results from mutations in a gene (XPV, also named POLH) which encodes for Polη, a member of the Y-DNA polymerase family. Although the presence and severity of skin and neurological dysfunctions differ between XP subtypes, there are overlapping clinical features among subtypes such that the sub-type cannot be deduced from the clinical features. In this study, in order to overcome this drawback, we undertook whole-exome sequencing in two XP sibs and their father. We identified a novel homozygous nonsense mutation (c.897T>G, p.Y299X) in POLH which causes the disease. Our results demonstrate that next generation sequencing is a powerful approach to rapid determination of XP genetic etiology.


Asunto(s)
Exoma/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Xerodermia Pigmentosa/genética , Adulto , Femenino , Humanos , Masculino , Linaje , Adulto Joven
4.
PLoS One ; 8(5): e63226, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23667589

RESUMEN

Non-Small-Cell-Lung-Cancer (NSCLC) represents approximately 85% of all lung cancers and remains poorly understood. While signaling pathways operative during organ development, including Sonic Hedgehog (Shh) and associated Gli transcription factors (Gli1-3), have recently been found to be reactivated in NSCLC, their functional role remains unclear. Here, we hypothesized that Shh/Gli1-3 could mediate NSCLC autonomous proliferation and epithelial/stromal signaling in the tumoral tissue. In this context, we have investigated the activity of Shh/Gli1-3 signaling in NSCLC in both, cancer and stromal cells. We report here that inhibition of Shh signaling induces a significant decrease in the proliferation of NSCLC cells. This effect is mediated by Gli1 and Gli2, but not Gli3, through regulation of cyclin D1 and cyclin D2 expression. While exogenous Shh was unable to induce signaling in either A549 lung adenocarcinoma or H520 lung squamous carcinoma cells, both cells were found to secrete Shh ligand, which induced fibroblast proliferation, survival, migration, invasion, and collagen synthesis. Furthermore, Shh secreted by NSCLC mediates the production of proangiogenic and metastatic factors in lung fibroblasts. Our results thus provide evidence that Shh plays an important role in mediating epithelial/mesenchymal crosstalk in NSCLC. While autonomous Gli activity controls NSCLC proliferation, increased Shh expression by NSCLC is associated with fibroblast activation in tumor-associated stroma. Our study highlights the relevance of studying stromal-associated cells in the context of NSCLC regarding new prognosis and therapeutic options.


Asunto(s)
Proteínas Hedgehog/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Mesodermo/patología , Factores de Transcripción/metabolismo , Animales , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colágeno/metabolismo , Ciclina D/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Proteínas Hedgehog/antagonistas & inhibidores , Humanos , Ligandos , Ratones , Invasividad Neoplásica , Transducción de Señal/efectos de los fármacos , Alcaloides de Veratrum/farmacología , Proteína con Dedos de Zinc GLI1
5.
J Cell Physiol ; 226(1): 276-84, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20665674

RESUMEN

DUSP6/MKP-3 is a cytoplasmic dual-specificity phosphatase specific for the MAP kinases ERK1/2. Previous data have shown that the MEK/ERK axis exerts a retro-control on its own signaling through transcriptional and post-translational regulation of DUSP6. We first confirm the key role of MEK/ERK in maintaining the levels of dusp6 mRNA, while PI3K/mTOR, p38 MAPK, and JNK signaling pathways had no significant effects. We further show that regulation of dusp6 mRNA stability plays a critical role in ERK-dependent regulation of dusp6 expression. Luciferase reporter constructs indicated that MEK/ERK signaling increased the half-life of dusp6 mRNA in a 3'untranslated region (3'UTR)-dependent manner. In addition, hypoxia, a hallmark of tumor growth, was found to increase both endogenous levels of dusp6 mRNA and the stability of the luciferase reporter constructs containing its 3'UTR, in a HIF-1-dependent manner. Nevertheless, a basal ERK activity was required for the response to hypoxia. Finally, Tristetraprolin (TTP), a member of the TIS11 CCCH zinc finger protein family, and PUM2, an homolog of drosophila pumilio, two proteins regulating mRNA stability reduced the levels of endogenous dusp6 mRNA and the activity of the dusp6/3'UTR luciferase reporter constructs. This study shows that post-transcriptional regulation is a key process in the control of DUSP6 expression.


Asunto(s)
Fosfatasa 6 de Especificidad Dual/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación de la Expresión Génica/fisiología , Quinasas Quinasa Quinasa PAM/metabolismo , Procesamiento Postranscripcional del ARN/fisiología , Línea Celular , Fosfatasa 6 de Especificidad Dual/genética , Humanos , Factor 1 Inducible por Hipoxia/genética , Factor 1 Inducible por Hipoxia/metabolismo , Quinasas Quinasa Quinasa PAM/genética , Estabilidad Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Transducción de Señal/fisiología , Tristetraprolina/genética , Tristetraprolina/metabolismo
6.
Rev. biol. trop ; 56(2): 473-485, jun. 2008. tab
Artículo en Español | LILACS | ID: lil-637653

RESUMEN

Natural concentration of antimalaric components in Tropical arthropods (in vitro). Alcohol, hexane and dichlorometane extracts of 751 samples of Costa Rican arthropods were studied for the presence of antimalaric components. With Plasmodium berghei we set an in vitro model in which the effect of the extract was determined by staining of the parasites with cresil brilliant blue. Active extracts at concentration of 50 mg or less, were considered positive. Promissory extracts were found in the orders Lepidoptera (24.1%), Coleoptera (32.8%), Hemiptera (38.5%) and Polydesmida (81.3%). Since most of the Lepidoptera samples were in the immature stages, the relation with the host plant was analyzed. Cannaceae, Flacourtiaceae, Crisobalanaceae, Lauraceae, Fagaceae, Ulmaceae, Rosaceae, Asteraceae, Rubiaceae, Lauraceae and Caprifoliaceae were related with the Lepidoptera larvae, and an antimalaric effect has been reported in most of these families. In the orders Polydesmida, Opiliones and Blattodea, the extract from adults also had some important effect, probably because all of them fed on plants. Polydesmida and Opiliones have chemical substances that probably serve as defensive purposes; these chemicals could also have some antiparasitic effect. Therefore, the detection of antimalaric components in arthropod species led to the identification of plants with promissory antimalaric components. Rev. Biol. Trop. 56 (2): 473-485. Epub 2008 June 30.


Extractos alcohólicos, hexánicos y diclorometánicos de 751 muestras de artrópodos fueron estudiados por la presencia de actividad antimalárica. En este trabajo se empleó un modelo murino usando el Plasmodium berghei, modelo que es biológicamente similar a la malaria humana. El estudio fue realizado determinando el efecto del extracto sobre el parásito por la inclusión o no del colorante azul de cresil brillante. Estimando como positivos aquellos extractos cuya actividad antimalárica se mostró en concentraciones no mayores de 50 mg, se encontró que los órdenes más promisorios fueron Lepidoptera (24.1%), Polydesmida (81.3%), Blattodea (25%) y Opiliones, entre otros. Las formas inmaduras de Lepidoptera fueron las más positivas, por lo que se analizaron las plantas hospederos de donde se alimentaban dichos organismos. Las familias de estas plantas eran Malvaceae, Acanthaceae, Rutaceae, Myrtaceae, Solanaceae, Fabaceae, Urticaceae, Anacardiaceae, Rosaceae, Asteraceae, Rubiaceae, Lauraceae y Caprifoliaceae. Especies de casi todas estas familias han sido reportadas con actividad antimalárica. En el caso de los órdenes Polydesmida, Opiliones y Blattodea, cuyas formas adultas presentaron alguna actividad contra P. berghei, encontramos que todos esos grupos se alimentan también de plantas. En el caso de Opiliones sus especies son predadores de lepidópteros, coleópteros, hemípteros fitófagos y otros artrópodos, además de que producen sustancias de defensas tales como alcoholes, cetonas y quinonas, entre otros, todo lo cual podría explicar la actividad encontrada. Algunas especies del Orden Polydesmida, también secretan ciertas sustancias químicas, las cuales podrían tener un efecto antiparasitario. Así, a través de este trabajo en artrópodos hemos llegado a identificar fuentes vegetales potenciales para componentes antimaláricos.


Asunto(s)
Animales , Ratones , Antimaláricos/farmacología , Artrópodos/química , Conducta Alimentaria/fisiología , Malaria/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos de Tejidos/farmacología , Antimaláricos/aislamiento & purificación , Artrópodos/clasificación , Artrópodos/fisiología , Modelos Animales de Enfermedad , Extractos de Tejidos/aislamiento & purificación
7.
Rev Biol Trop ; 56(2): 473-85, 2008 Jun.
Artículo en Español | MEDLINE | ID: mdl-19256421

RESUMEN

Alcohol, hexane and dichlorometane extracts of 751 samples of Costa Rican arthropods were studied for the presence of antimalaric components. With Plasmodium berghei we set an in vitro model in which the effect of the extract was determined by staining of the parasites with cresil brilliant blue. Active extracts at concentration of 50 mg or less, were considered positive. Promissory extracts were found in the orders Lepidoptera (24.1%), Coleoptera (32.8%), Hemiptera (38.5%) and Polydesmida (81.3%). Since most of the Lepidoptera samples were in the immature stages, the relation with the host plant was analyzed. Cannaceae, Flacourtiaceae, Crisobalanaceae, Lauraceae, Fagaceae, Ulmaceae, Rosaceae, Asteraceae, Rubiaceae, Lauraceae and Caprifoliaceae were related with the Lepidoptera larvae, and an antimalaric effect has been reported in most of these families. In the orders Polydesmida, Opiliones and Blattodea, the extract from adults also had some important effect, probably because all of them fed on plants. Polydesmida and Opiliones have chemical substances that probably serve as defensive purposes; these chemicals could also have some antiparasitic effect. Therefore, the detection of antimalaric components in arthropod species led to the identification of plants with promissory antimalaric components.


Asunto(s)
Antimaláricos/farmacología , Artrópodos/química , Conducta Alimentaria/fisiología , Malaria/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos de Tejidos/farmacología , Animales , Antimaláricos/aislamiento & purificación , Artrópodos/clasificación , Artrópodos/fisiología , Modelos Animales de Enfermedad , Ratones , Extractos de Tejidos/aislamiento & purificación
8.
Rev. biol. trop ; 53(3/4): 437-445, sept.-dic. 2005. ilus, tab
Artículo en Español | LILACS | ID: lil-451272

RESUMEN

Fecal samples of 102 howler monkeys (Alouatta palliata) from several sites of Costa Rica were studied for intestinal parasites. The zones studied were: Central Valley (San Ramón, Alajuela), Central Pacific (Chomes and Manuel Antonio National Park, Puntarenas), North Pacific (Palo Verde Park and Playa Potrero, Guanacaste), Chira Island in the Nicoya Gulf and Caribean area (Cahuita, Limón). Animals were anesthetized with dards containing Telazol in order to collect the fecal material; some monkeys defecated spontaneously and others by direct stimulation. Samples were studied in saline solution (0.85%) and a Iodine solution, or stained with Haematoxylin. The material was also cultured in Dobell culture medium to determine the presence of amoeba and flagellates. Strongyloides, Controrchis, Trypanoxyuris genera were found in 3.4% of the samples. In addition 16.7% to 80% of the animals showed protozoa infection with Endolimax, Entamoeba, Trichomonas and Giardia. It is discussed the relationships of parasite infection with environmental conditions, animal population and human presence, specially in the monkey conservation programs point of view


Se estudiaron las heces de 102 monos de la especie Alouatta palliata (monos aulladores o congos) de las siguientes regiones de Costa Rica. Valle Central: San Ramón (Alajuela); Pacífico Central: Isla Chira y Parque Manuel Antonio (Puntarenas); Pacífico Norte: Palo Verde, Playa Potrero, Nicoya (Guanacaste) y Caribe: Cahuita (Limón). Los animales capturados fueron anestesiados con dardos conteniendo Telazol®. La mayoría defecaron espontáneamente o se les estimulaba a defecar. Las muestras se estudiaron en el laboratorio en forma directa en solución salina (0.85%) y una solución de yodo o teñidas con hematoxilina para identificar los parásitos correspondientes. El material fue cultivado en el medio de Dobell para determinar la presencia de amebas y flagelados. Se encontraron helmintos de los géneros Trypanoxyuris, Strongyloides y Controrchis y protozoarios de los géneros Endolimax, Entamoeba, Trichomonas y Giardia. Los porcentajes de infección por protozoarios oscilaron entre 16.7% y 80% y se encontraron helmintos en un 3.4% a un 80% de los animales de acuerdo con la zona estudiada. No se encontraron diferencias importantes de parasitosis relacionadas con el sexo pero si existió mayor infección en los animales más jóvenes. Se establece la relación entre los índices de infección y algunos parámetros tales como las áreas estudiadas, el peso de los animales y el contacto con el ser humano


Asunto(s)
Humanos , Animales , Masculino , Femenino , Alouatta/parasitología , Helmintiasis Animal/parasitología , Parasitosis Intestinales/veterinaria , Enfermedades de los Monos/parasitología , Infecciones Protozoarias en Animales/parasitología , Costa Rica , Heces/parasitología , Helmintiasis Animal/epidemiología , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Enfermedades de los Monos/epidemiología , Infecciones Protozoarias en Animales/epidemiología
9.
Rev Biol Trop ; 53(3-4): 437-45, 2005.
Artículo en Español | MEDLINE | ID: mdl-17354453

RESUMEN

Fecal samples of 102 howler monkeys (Alouatta palliata) from several sites of Costa Rica were studied for intestinal parasites. The zones studied were: Central Valley (San Ramón, Alajuela), Central Pacific (Chomes and Manuel Antonio National Park. Puntarenas), North Pacific (Palo Verde Park and Playa Potrero, Guanacaste). Chira Island in the Nicoya Gulf and Caribean area (Cahuita. Limón). Animals were anesthetized with dards containing Telazol in order to collect the fecal material; some monkeys defecated spontaneously and others by direct stimulation. Samples were studied in saline solution (0.85%) and a Iodine solution, or stained with Haematoxylin. The material was also cultured in Dobell culture medium to determine the presence of amoeba and flagellates. Strongvloides. Controrchis. Trypanoxyuris genera were found in 3.4% of the samples. In addition 16.7% to 80% of the animals showed protozoa infection with Endolimax, Entamoeba, Trichomonas and Giardia. It is discussed the relationships of parasite infection with environmental conditions, animal population and human presence, specially in the monkey conservation programs point of view.


Asunto(s)
Alouatta/parasitología , Helmintiasis Animal/parasitología , Parasitosis Intestinales/veterinaria , Enfermedades de los Monos/parasitología , Infecciones Protozoarias en Animales/parasitología , Animales , Costa Rica/epidemiología , Heces/parasitología , Femenino , Helmintiasis Animal/epidemiología , Humanos , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Masculino , Enfermedades de los Monos/epidemiología , Infecciones Protozoarias en Animales/epidemiología
10.
Rev. biol. trop ; 51(2): 317-320, jun. 2003. tab
Artículo en Español | LILACS | ID: lil-365924

RESUMEN

Treatment of toxoplasmosis usually causes secondary effects. It is important to find active substances extracted from natural organisms. In this work we studied some arthropod extracts that have effect against Toxoplasma multiplication inside mouse macrophages. After studying 382 extracts, 23 were selected on the basis of the activity and we found that 13 extracts from orders Polydesmida, Lepidoptera, Orthoptera and Hymenoptera exerted an important inhibition of Toxoplasma multiplication.


Asunto(s)
Animales , Ratones , Artrópodos , Macrófagos Peritoneales , Extractos de Tejidos , Toxoplasma , Artrópodos , Factores de Tiempo
11.
Rev Biol Trop ; 51(2): 317-20, 2003 Jun.
Artículo en Español | MEDLINE | ID: mdl-15162724

RESUMEN

Treatment of toxoplasmosis usually causes secondary effects. It is important to find active substances extracted from natural organisms. In this work we studied some arthropod extracts that have effect against Toxoplasma multiplication inside mouse macrophages. After studying 382 extracts, 23 were selected on the basis of the activity and we found that 13 extracts from orders Polydesmida, Lepidoptera, Orthoptera and Hymenoptera exerted an important inhibition of Toxoplasma multiplication.


Asunto(s)
Artrópodos/química , Macrófagos Peritoneales/parasitología , Extractos de Tejidos/farmacología , Toxoplasma/efectos de los fármacos , Animales , Artrópodos/clasificación , Ratones , Factores de Tiempo
12.
Acta méd. costarric ; 41(3): 39-42, sept. 1999. ilus
Artículo en Español | LILACS | ID: lil-257295

RESUMEN

La cyclospora cayetanensis es uno de los tantos parásitos que se están adaptando rápidamente al hombre y que en conjunto con las especies de la criptosporidiosis, hoy se encuentran afectando a individuos tanto inmunosupresos como inmunocompetentes. El sida parece ser en todos estos casos el elemento común de inicio de la parasitosis humana con estos organismos, presentes usualmente en animales de una escala zoológica lejana. Luego de romper las barreras, estos organismos se adaptan al ser humano inmunológicamente normal. La ciclosporosis es conocida en el mundo entero pero en Costa Rica no había sido reportada hasta ahora. Este trabajo informa del primer caso humano en Costa Rica y como corolario se presenta una revisión de la parasitosis con el propósito de ayudar a profesionales interesados en el área de la salud a conocer, diagnosticar y cambatir mejor


Asunto(s)
Humanos , Cryptosporidium , Microbiología , Parásitos , Costa Rica
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