Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Rev. biol. trop ; 69(supl. 1)mar. 2021.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1507790

RESUMO

Introduction: Identifying critical habitats for vulnerable elasmobranch species is crucial for effective conservation measures. The Munk's devil ray (Mobula munkiana) is endemic to the Eastern Pacific, but yet little is known about its biology, ecology, and habitat use. As filter feeders, it is assumed that this species concentrates at high-productive upwelling regions, such as the Costa Rican Dome. Like many elasmobranchs, its populations are highly depleted and require urgent information to inform better conservation measures. Objective: The study was conducted to gain information on a unique behavior observed in juvenile M. munkiana, so further information can be provided on early life stages of this vulnerable species. Methods: From June to September 2017 and in August 2018, the feeding behavior of juvenile Mobula munkiana was observed in two shallow bays located at Punta Descartes, North Pacific Costa Rica. Individuals were captured using a non-lethal method to obtain data on size, weight, and sex distribution. Plankton samples (n = 100) were taken at both bays throughout the months to infer diet composition. Results: Munk's devil rays showed a repetitive swimming movement parallel to the beach, feeding exclusively in the shallow breaking zone of the low tide waves at depth <50cm. A total of 12 M. munkiana (11 live and one found dead) indicated a juvenile feeding aggregation ranging from 490 - 610mm in disk width and 1400 - 2300gr in weight. The sex ratio (males to females) was 3:1. Zooplankton of the order Mysidacae was found in the highest abundance in the breaking zone. Conclusions: The specific behavior and seasonal occurrence of juvenile Munk's devil rays in this area seem to be driven by prey abundance. More research is needed to conclude the presence of reproductive adults at deeper depths and the year-round habitat use of Punta Descartes. The area is threatened by unsustainable development and requires realistic management strategies to guarantee the survival of vulnerable species and their critical habitats.


Introducción: La identificación de hábitats críticos para especies vulnerables de elasmobranquios es crucial para tomar medidas de conservación efectivas. La manta diablo o raya de Munk (Mobula munkiana) es endémica del Pacífico Oriental y se sabe poco sobre su biología, ecología y uso de hábitat. Como filtradores, se asume que se concentran en regiones de afloramiento con alta productividad; sus poblaciones se consideran en disminución y requieren información urgente para fundamentar medidas de conservación. Objetivo: El estudio se realizó para obtener información sobre un comportamiento de alimentación observado en juveniles de M. munkiana, con el fin de proporcionar más información sobre las primeras etapas de vida de esta especie considerada vulnerable a la extinción. Métodos: De junio a setiembre de 2017 y en agosto de 2018, se observó el comportamiento de alimentación de los juveniles de M. munkiana en dos bahías poco profundas de Punta Descartes, en el Pacífico norte de Costa Rica. Los individuos fueron capturados utilizando un método no letal para obtener datos sobre el tamaño, peso y sexo. Se tomaron 100 muestras de plancton en las bahías para inferir la composición de la dieta. Resultados: Las rayas mostraron un comportamiento de natación repetitivo paralelo a la playa, alimentándose exclusivamente en la zona de rompimiento de las olas en marea baja, a menos de 50 cm de profundidad. Un total de 12 rayas M. munkiana (11 vivas y una encontrada muerta) indicaron una agregación de juveniles para alimentarse. Los anchos de disco variaron de 490 a 610 mm y el peso entre 1400 a 2300 g. La proporción sexual (machos: hembras) fue de 3:1. En la zona donde rompían las olas se encontró principalmente el orden Mysidaceae. Conclusiones: El comportamiento específico y la ocurrencia estacional de M. munkiana en la zona de estudio parecen estar impulsados por la abundancia de presas. Se necesita más investigación para concluir la presencia de adultos reproductivos a mayor profundidad y sobre el uso de hábitat en los alrededores de Punta Descartes durante todo el año. Esta área se encuentra amenazada por un desarrollo insostenible y requiere estrategias de manejo realistas para garantizar la supervivencia de especies vulnerables y sus hábitats críticos.

2.
Rev. colomb. cienc. pecu ; 33(4): 252-263, Oct.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1376896

RESUMO

Abstract Background: Devilfish (Pterygoplichthys sp.) is a pest of high impact in aquaculture production systems. Through a biological fermentation process, it could be used as a source of protein for dairy cows. However, milk palatability and smell could be limiting factors. Objective: to evaluate the quality of milk from cows supplemented with biological fish silage (Pterygoplichthys sp.) as a protein source. Methods: The treatments (T) evaluated were T1, 0% biological fish silage; T2, 10% biological fish silage; and T3, 20% biological fish silage. Twelve randomly selected cows were used in a Latin square experimental design, in which three treatments were tested with all of the cows during three time periods. Each period lasted 20 days (15-day adaptation period and 5-day experimental phase). Milk was analyzed for physicochemical, microbiological, sanitary condition and sensory characteristics. Analyses of variance were performed for all the response variables. Results: No significant differences for physicochemical variables were found among the treatments studied. Differences were observed in microbiological and sanitary variables among treatments, but values were in the range for high quality milk standards (˂100,000 CFU mL-1 aerobic mesophilic bacteria, and ˂400,000 somatic cells mL-1). In the sensory analyses, panelists did not detect strange odors nor fishy taste or odor in the milk of any of the treatments. Conclusion: Biological fish silage can be included up to 20% as a protein source in supplements for lactating cows.


Resumen Antecedentes: el pez diablo (Pterygoplichthys sp.) es una plaga de alto impacto en los sistemas de producción acuícolas. A través de los procesos de fermentación biológicos podría ser utilizado como fuente de proteína en los suplementos para vacas en producción. Sin embargo, el sabor y olor a pescado en la leche pudiera ser una limitante. Objetivos: evaluar la calidad de la leche de vacas suplementadas con ensilaje biológico de pez diablo como fuente de proteína. Métodos: los tratamientos (T) evaluados fueron T1, 0% de ensilaje biológico de Pterygoplichthys sp.; T2, 10% de ensilaje biológico de Pterygoplichthys sp.; y T3, 20% de ensilaje biológico de Pterygoplichthys sp.. Se utilizaron doce vacas seleccionadas al azar en un diseño experimental de cuadrado latino. Cada período tuvo una duración de 20 días (período de adaptación de 15 días y fase experimental de 5 días). La leche fue analizada para determinar su condición fisicoquímica, microbiológica, sanitaria y sensorial. Se realizaron análisis de varianza para todas las variables. Resultados: no se encontraron diferencias significativas entre los tratamientos estudiados para las variables fisicoquímicas las cuales estuvieron dentro de los estándares de leche de mayor calidad. Se observaron diferencias en las variables microbiológicas y sanitarias entre los tratamientos, pero los valores estuvieron dentro del rango para los estándares de leche de mayor calidad (˂100.000 UFC ml-1 de bacterias mesofílicas aeróbicas y ˂400.000 células somáticas ml-1). Los análisis sensoriales no detectaron olores extraños, ni olor ó sabor a pescado en la leche de los tratamientos estudiados. Conclusiones: se puede incluir hasta 20% de ensilaje biológico de Pterygoplichthys sp. como fuente de proteína en los suplementos de vacas en producción.


Resumo Antecedentes: o peixe cascudo (Pterygoplichthys sp.) é uma praga de alto impacto nos sistemas de produção aquícola. Por meio de processos de fermentação biológica poderia ser usado como fonte de proteína em suplementos para vacas em produção, porém o sabor e cheiro de peixe no leite podem ser uma limitação. Objetivos: avaliar a qualidade do leite de vacas suplementadas com silagem biológica de peixe cascudo como fonte de proteína. Métodos: os tratamentos (T) avaliados foram T1, 0% da silagem biológica de Pterygoplichthys sp.; T2, silagem biológica a 10% de Pterygoplichthys sp.; e T3, silagem biológica a 20% de Pterygoplichthys sp. Doze vacas selecionadas aleatoriamente foram utilizadas em um delineamento experimental de quadrado latino. Cada período durou 20 dias (período de adaptação de 15 dias e fase experimental de 5 dias). O leite foi analisado para determinar sua condição físico-química, microbiológica, sanitária e sensorial. Análises de variância foram realizadas para todas as variáveis. Resultados: não foram encontradas diferenças significativas entre os tratamentos estudados para as variáveis físico-químicas, os valores estavam dentro dos mais altos padrões de qualidade do leite. Observaram- se diferenças nas variáveis microbiológicas e sanitárias entre os tratamentos, mas os valores estavam dentro dos limites para os mais altos padrões de leite de qualidade (˂100.000 CFU ml-1 de bactérias mesofílicas aeróbicas e ˂400.000 células somáticas ml-1). As análises sensoriais não detectaram odores estranhos, nem cheiro ou sabor de peixe no leite dos tratamentos estudados. Conclusões: a silagem biológica de peixes pode ser incluída em até 20% como fonte de proteína em suplementos de vacas em produção.

3.
Rev. bras. psicanál ; 52(1): 67-80, jan.-mar. 2018. ilus
Artigo em Português | LILACS-Express | LILACS, INDEXPSI | ID: biblio-1288720

RESUMO

Este trabalho busca circunscrever alguns aspectos do pacto demoníaco por meio de formas que assume na literatura e na música. Empreende uma aproximação com os estados melancólicos, produzindo ressonâncias no campo psicanalítico. Nesse percurso, as funções disjuntivas e conjuntivas são exploradas enquanto elementos diabólicos indispensáveis aos sentimentos de vitalidade e ao trabalho analítico com certos pacientes. Apresentam-se duas breves situações clínicas associadas ao tema.


The purpose of this paper is to examine some aspects of "the chord of evil", by connecting it to its ways of expression in literature and music. As the author approaches melancholic states, his article invades the psychoanalytic field. In this path, he explores disjunctive and conjunctive functions as diabolic, evil elements that are essential to feelings of vitality and to the analytic work with certain patients. The author presents two brief clinical cases about this theme.


El presente trabajo tiene como objetivo circunscribir algunos aspectos del "pacto diabólico", relacionándolo con las formas que asume en la literatura y la música. Se emprende una aproximación con los estados melancólicos, trayendo resonancias al campo psicoanalítico. Durante este recorrido, las funciones disyuntivas y conjuntivas se exploran como elementos diabólicos indispensables en los sentimientos de vitalidad y en el trabajo analítico de determinados pacientes. Se presentan dos casos clínicos relacionados con el tema.


Le présent travail cherche à circonscrire certains aspects du "pacte diabolique" en rapport avec les formes qu'il prend chez la littérature et la musique. On entreprend un rapprochement avec les états mélancoliques, en apportant des résonances au champ psychanalytique. Pendant ce parcours, on explore les fonctions disjonctives et conjonctives en tant qu'éléments diaboliques indispensables aux sentiments de vitalité et au travail analytique avec certains patients. On présente deux brèves situations cliniques concernant le thème.

4.
Bol. méd. Hosp. Infant. Méx ; 73(6): 365-371, Nov.-Dec. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-951254

RESUMO

Abstract: In mammals, apoptosis is the main mechanism to eliminate unwanted cells, securing tissue homeostasis and consequently maintaining the health in the organism. Classically, apoptosis culminates with the activation of caspases, which are enzymes that display cysteine protease activity to degrade specific substrates implied in essential cellular processes. This process is highly regulated. A key regulation mechanism is mediated by the Inhibitor of Apoptosis Proteins (IAPs) family members, which inhibit the activated forms of caspases through physical interaction with them. Smac/DIABLO, a mitochondrial protein that is translocated to the cytoplasm in apoptotic conditions, derepresses the IAP-mediated caspase inhibition through physical interaction with IAPs. The first four amino acids (AVPI) of Smac/DIABLO mediate the interaction with IAPs and subsequent apoptosis induction. This interaction has lead to the creation of small molecules mimicking the AVPI segment for potential anticancer therapy. Nevertheless, several studies have pointed out the existence of AVPI-independent functions of Smac/DIABLO. The aim of this review was to provide a landscape of these underestimated AVPI-independent biological functions that have been observed using different approaches, such as the study of endogenous splice variant isoforms and truncated and mutated artificial proteins.


Resumen: La apoptosis es uno de los principales mecanismos en los mamíferos para eliminar células no deseadas, asegurando la homeostasis de los tejidos y, consecuentemente, la salud de los mismos. De forma clásica, la apoptosis finaliza con la activación de las caspasas, enzimas que despliegan actividad de proteasas de cisteína, involucradas en la degradación de sustratos específicos implicados en procesos celulares esenciales. El proceso apoptótico se encuentra altamente regulado. Un mecanismo de regulación es el mediado por los miembros de la familia de las Proteínas Inhibidoras de la Apoptosis (PIA), las cuales inhiben a las formas activas de las caspasas a través de la interacción física con estas. Smac/DIABLO, proteína mitocondrial que es translocada al citoplasma en condiciones apoptóticas, antagoniza la inhibición de las caspasas mediante su interacción física con las PIA. Los cuatro primeros aminoácidos (AVPI) de Smac/DIABLO intervienen en su asociación con las PIA y la subsecuente inducción apoptótica. Esto ha guiado a la generación de pequeñas moléculas miméticas del segmento AVPI para el uso potencial como una terapia anti-cancerígena. Sin embargo, varios estudios han indicado la presencia de funciones en Smac/DIABLO independientes del AVPI. El objetivo de esta revisión fue proporcionar un panorama de estas funciones biológicas desestimadas —independientes al AVPI— las cuales se han observado utilizando diferentes aproximaciones, como el estudio de las isoformas generadas por el procesamiento alternativo del gen y la síntesis de proteínas artificialmente mutadas.

5.
Estilos clín ; 16(1): 246-259, jun. 2011.
Artigo em Português | LILACS | ID: lil-603348

RESUMO

Este artigo trata da questão do mal, do desejo e suas repercussões no campo educacional. Pensar a educação a partir da psicanálise implica aceitar a falta, a dimensão do inconsciente, o erro, as aberrações, os equívocos e, principalmente, as múltiplas possibilidades de significações. A condição desejante não pode ser universalizada, mas pode ser compreendida. O diabo surge como resistência e desejo, em contraponto a direção do bem e a moralidade silenciadora dos modos de existir. O que propomos nesse trabalho é uma abertura para o exercício do pensar.


This article deals with the problem of evil and desire, and their repercussions en the area of education. Thinking about education by way of a psychoanalytical base implies acceptance of one's lack, one's unconsciousness, and ones errors, aberrations, mistakes and principally one's multiple possibilities of meaning with respect to the signs in one's environment. The condition of desire cannot be universalized, but it can be understood. The devil appears, as resistance and desire, as counterpoint toward good and the moral silencer of means of existence. We propose an opening of thought and dialogue along these lines.


Este artículo se trata del problema del mal y del deseo y sus repercusiones en el campo educacional. Pensar en la educación desde la base de la psicoanálisis implica aceptación de lo que le falta a uno, la dimensión de la inconsciencia de uno, y sus errores, aberraciones, equivocaciones y principalmente las múltiples posibilidades de significación con respecto a los signos en sus alrededores. La condición del deseo no puede ser universalizada, pero puede ser comprendida. Surge el diablo como resistencia y deseo, contrapunteando en la dirección del bien y la moralidad silenciadora de los modos de existir. Lo que proponemos en este trabajo, entonces, es una abertura para ejercitar el pensamiento.


Assuntos
Educação , Educação da População , Psicanálise , Teoria Psicanalítica
6.
Korean Journal of Pathology ; : 397-405, 2011.
Artigo em Inglês | WPRIM | ID: wpr-217088

RESUMO

BACKGROUND: The expression of the inhibitor of apoptosis proteins (IAPs) family has not been fully investigated in colorectal carcinomas. This study investigated IAP expression in colorectal carcinomas and assessed their prognostic significance. METHODS: Livin, XIAP, and SMAC/DIABLO expression was assessed by immunohistochemistry in 159 colorectal carcinomas. Correlations between protein expression and clinicopathological features were evaluated. The survival data analysis was estimated according to the Kaplan-Meier method. RESULTS: Increased expression of IAPs in cancer tissues compared to surrounding nonneoplastic counterparts was observed in 67 cases (42.1%) for Livin, 50 cases (31.4%) for XIAP, and 68 cases (42.8%) for SMAC. A significant correlation was found between Livin expression and tumor differentiation, and SMAC expression and tumor location. The recurrence-free and overall survival of patients with low Livin expression were inferior to those of patients with high Livin expression (p=0.054 and 0.095, respectively). High XIAP expression was significantly associated with shorter progression-free survival (p= 0.041). CONCLUSIONS: Our study demonstrated that altered expression of IAP family members, including Livin, XIAP, and SMAC, is frequent in colorectal carcinoma. This result suggests that high Livin expression and low XIAP expression may be a favorable prognostic implication related to patient survival.


Assuntos
Humanos , Apoptose , Neoplasias Colorretais , Intervalo Livre de Doença , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Mitocondriais , Prognóstico , Proteínas , Estatística como Assunto , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
7.
Chinese Journal of Pancreatology ; (6): 177-179, 2010.
Artigo em Chinês | WPRIM | ID: wpr-388954

RESUMO

Objective To investigate the expression of Smac/DIABLO, XIAP mRNA in acute pancreatitis (AP) and the relationship with the severity in rats.Methods Fifty-four SD rats were randomly divided into three groups:sham-operation (SO) group, acute edematous pancreatitis (AEP) group and acute necrotizing pancreatitis (ANP) group.The models of AEP and ANP were induced by retrograde injection of 1% and 3.5% sodium deoxycholate into the pancreaticobiliary duct respectively.The specimens of pancreatic tissue at 3 h, 6 h, 12 h were collected, pathological changes of the pancreas were observed, apeptosis in pancreas were detected by TUNEL method and the expression of Smac/DIABLO, XIAP mRNA were analyzed by real-time PCR.Results Pathological changes of the pancreas confirmed the establishment of AEP and ANP.Apeptosis indexes in SO group, AEP group and ANP group were 0.67±0.82, 6.62 ±0.78 and 4.70 ±0.82, and the differences were significant (P< 0.05).The expression of Smac/DIABLO mRNA of AEP group increased with time, while the expression of ANP group decreased with time.Compared with SO group, Smac/DIABLO mRNA expressions at 6 h in AEP and ANP group were 2.41 ± 0.92 and 1.47± 0.53, and the differences were significant (P<0.05).By contrast, the expressions of XIAP mRNA in AEP group decreased with time,while the expressions in ANP group increased with time.The expressionsof XIAP mRNA at 6 h in AEP and ANP group were 5.51 ± 1.07 and 6.99 ± 1.00, and the differences were significant (P<0.05).Conclusions In acute pancreatitis, the expression of Smac/DIABLO mRNA was consistent with the apoptosis of pancreatic acinar cells, but not consistent with the severity of pancreatitis.The expression of XIAP mRNA was consistent with the severity of pancreatitis.Smac/DIABLO, XIAP mRNA is associated with regulation of apoptosis.

8.
International Journal of Pediatrics ; (6): 403-405, 2010.
Artigo em Chinês | WPRIM | ID: wpr-388540

RESUMO

Ischemia-reperfusion after neonatal asphyxia is a key factor in renal injury,which often leads to apoptosis of tubular epithelial cells.Apoptosis is an important form of injury for renal tubular epithelial cells after asphyxia.Smac/DIABLO is released to the cytosol in response to diverse apoptotic stimuli while mitochondrial targeting signal peptide is removed.In the cytosol,Smac/DIABLO interacts and antagonizes inhibitors of apoptosis proteins,thus allowing the activation of caspases and apoptosis.And thus it increases the ischemia-reperfusion renal injury,leading to acute renal failure.

9.
Rev. argent. microbiol ; 41(3): 134-140, jul.-sep. 2009. graf
Artigo em Espanhol | LILACS | ID: lil-634627

RESUMO

El virus de la Lengua azul (VLA) es un ARN virus de doble cadena que induce apoptosis tanto en cultivos celulares como en tejidos blanco. Con el fin de dilucidar el mecanismo de apoptosis en la infección por el VLA, en el presente trabajo examinamos en detalle, por la técnica de Western blot, las señales celulares de caspasas, Bax, citocromo c, Smac/DIABLO y factor nuclear kappa B (NF-kB) que se activan en la infección viral. Hemos comprobado que luego de la infección in vitro con el VLA, se detectó la activación de la caspasa 8 y con ello el mecanismo extrínseco de la apoptosis. También detectamos por primera vez no sólo la activación de miembros de la familia Bcl-2 (Bax), sino también la liberación del citocromo c y la proteína Smac/DIABLO, confirmando que en la infección por el VLA está involucrado el mecanismo secuencial intrínseco de la apoptosis. Asimismo, demostramos que la infección por el VLA activa el NF-kB y que la apoptosis es sustancialmente reducida mediante la inhibición del mismo. La activación de las señales celulares tales como Bax, citocromo c, Smac/DIABLO y NF-kB presentados en este trabajo, esclarecen los mecanismos apoptóticos durante la infección por el VLA para una mayor comprensión del papel primario que juega la apoptosis en la patogénesis del virus.


Bluetongue (BTV) is a double-stranded RNA virus that induces apoptosis both in mammalian cell cultures and in target tissues. To elucidate the apoptosis pathways in BTV infection, we have examined in detail the apoptosis mechanism by examination of caspases, Bax, cytochrome c, Smac/DIABLO and NF-kB signalling pathways. In this report, after cell infection with BTV, the activation of caspase 8 was detected, proving the extrinsic receptor binding apoptotic pathway. Apoptosis followed a sequential pathway involving the detection of activated Bcl-2 family members. Furthermore, its translocation to the mitochondria, as well as the release of cytochrome c and Smac/Diablo confirmed that BTV apoptosis involves the sequential intrinsic pathway. In addition, we demonstrated that NF-kB was activated following BTV infection and cell treatment with an inhibitor peptide before BTV infection, prevented NF-kB activation and substantially reduced cellular apoptosis. Our accumulating data concerning the activation of Bax, cytochrome c, Smac/DIABLO and NF-kB clarify the mechanism of apoptosis during BTV infection, and confer a better understanding of the primary role of apoptosis in BTV pathogenesis.


Assuntos
Humanos , Apoptose/fisiologia , Vírus Bluetongue/fisiologia , Transdução de Sinais/fisiologia , Efeito Citopatogênico Viral , Caspases/metabolismo , Citocromos c/metabolismo , Ativação Enzimática , Células HeLa/virologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mitocôndrias/fisiologia , Proteínas Mitocondriais/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Peptídeos/farmacologia
10.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 304-307, 2008.
Artigo em Chinês | WPRIM | ID: wpr-284583

RESUMO

The effects of synthetic Smac peptide (SmacN7) on chemotherapeutic sensitivity of bladder cancer cells were investigated. SmacN7 penetratin peptide was synthesized and delivered into T24 cells. MTT assay was used to evaluate the viability of T24 cells induced by low-dosage of MMC. Flow cytometry was used to analyze the proportions of apoptosis. Western blot was used to detect the expression of XIAP and Caspase-3. The activity of Caspase-3 was measured and the effect of SmacN7 combined with MMC on T24 cell lines was also determined. The results showed that SmacN7 penetratin peptide could successfully interact with endogenous XIAP, increase the proportions of apoptosis of T24 cell lines induced by low-dosage of MMC in a dose-and time-dependent manner. An obvious down-regulation of XIAP expression and up-regulation of Caspase-3 was identified by Western blot. The activity of Caspase-3 in experimental group was significantly increased as compared with that in the control group. As compared with MMC group, the viability of T24 cells in SmacN7 penetratin peptide + MMC group was markedly decreased to 2.22 and 3.61 folds at 24h and 48h respectively. It was concluded that SmacN7 penetratin peptide could act as a cell-permeable IAP inhibitor, inhibit the proliferation, induce apoptosis and enhance the chemo-sensitivity of bladder cancer cells to MMC. These findings indicate that SmacN7 penetratin peptide may be a very promising ageut for bladder cancer treatment when used in combination with chemotherapy.

11.
Rio de Janeiro; s.n; 2007. xx,123 p.
Tese em Português | LILACS, ColecionaSUS, Inca | ID: biblio-927982

RESUMO

Leucemia mielóide crônica (LMC) é uma doença mieloproliferativa com expansão clonal de células malignas. O cromossomo Philadelphia, derivado da translocação recíproca entre os cromossomos 9 e 22, resulta em um gene quimérico chamado BCR-ABL, encontrado em 90 (por cento) dos pacientes com LMC, sendo atribuída a essa quimera a patogênese da LMC. Imatinibe, um fármaco alvo-específico, liga-se e estabiliza a forma inativa da Bcr-Abl impedindo os efeitos da proteína. O desenvolvimento de resistência ao Imatinibe e a persistência de doença residual mínima tem desanimado os investigadores, além disso, respostas ao Imatinibe são menos freqüentes e mais curtas em pacientes que se encontram nos estágios mais avançados da LMC. Levando em conta que a resistência ao Imatinibe poder ser multifatorial, a identificação dos mecanismos de envolvidos na resistência pode levar a ganhos em sobrevida para os pacientes...


Assuntos
Humanos , Proteínas Reguladoras de Apoptose , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas Associadas à Resistência a Múltiplos Medicamentos
12.
China Oncology ; (12)2006.
Artigo em Chinês | WPRIM | ID: wpr-676871

RESUMO

Background and purpose:Smac/DIABLO was the only apoptosis-related protein that could inhibit IAPs directly and simultaneously.The four amino-residual AVPI(Ala-Val-Pro-lie)in its N-terminal was the very important domain that could stimulate apoptosis.This study investigated the effect of synthetic Smac peptide (SmacN7) on chemotherapy sensitivity of bladder cancer cells.Methods:SmacN7 penetratin peptide was synthesized and delivered into T24 cells.MTT assay was adopted to evaluate the viability of T24 cells induced by low-dosage of MMC. Flow cytometry was applied to analyze the proportion of apoptosis and Western blot was used to detect the expression of XIAP and caspase-3;The activity of caspase-3 was measured and the effect of SmacN7 combined with MMC on T24 cell lines was also determined.Results:SmacN7 penetratin peptide could successfully interact with endogenous XIAP and increase the proportions of apoptosis of T24 cell lines induced by low-dosage of MMC in a dose-and time- dependent manner.An obvious down-regulation of XIAP expression and up-regulation of caspase-3 was identified by Western blot.The activity of caspase-3 in experimental group was significantly increased as compared with that in the control group;Combining the treatment with SmacN7 penetratin peptide,the viability of T24 cells decreased to 55% and 72.7% in 24 hrs and 48 hrs respectively.Conclusion:SmacN7 penetratin peptide could act as a cell-permeable IAP inhibitor,inhibit the proliferation,induce apoptosis and enhance the chemo-sensitivity of bladder cancer cells to MMC. When combined with chemotherapy,it may be a very promising strategy for bladder cancer therapy.

13.
China Oncology ; (12)2001.
Artigo em Chinês | WPRIM | ID: wpr-545920

RESUMO

Background and purpose:The Smac/DIABLO(the second mitochondrial derived activator of caspase/direct IAP binding protein with low pI)is a new kind of mitochondria protein,it inhibits IAPs(inhibitors of apoptosis protein),including Survivin,and activates caspase-9 and caspase-3,accordingly promotes apoptosis.In this study,we investigated the effect of over-expressing mitochondrial protein-Smac/DIABLO while silencing inhibitor of apoptosis protein-Survivin on the cell growth,cell cycle and apoptosis of human colon cancer cells through cotransfecting both genes.Methods:Constructed survivin-shRNA-EGFP plasmid was transected with Smac-pcDNA3.1 plasmid into Lovo cells at either half each dose or total dose,respectively.Western blot was used to survey the protein level of Smac and Survivin;Hoechst 33258 staining was used to detect the karyomorphological diversity of apoptotic cells and evaluate apoptotic ratio roughly;PI staining and flow cytometry analysis were used to examine cell cycle;caspase-3 Detection Kits was used to detect the activity of caspase-3.Results:The expression of Smac protein increased but Survivin protein decreased 48 hr after transfection.Karyomorphological diversify of apoptotic cells were obviously observed by hoechst 33258 staining.The apoptosis rate in Smav+Survivin shRNA group was(18.5?1.7)%,which was higher than that in Smac group(9.6?1.8)% and Survivin shRNA group(15.0?0.3)%,and all of three groups were significantly higher than the control groups;The cells of G0/G1 phase increased to(51.0?6.2)% in Smac group,and the cells of S stage increased to(53.3?1.3)% in Survivin shRNA group(P

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA