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1.
Genes Brain Behav ; 12(6): 595-603, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23790110

RESUMO

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder associated with FMR1 gene premutation alleles (55-200 CGG repeats). Fragile X-associated tremor/ataxia syndrome clinical core features include action tremor, gait ataxia, cognitive deficits progressing to dementia, and frequently parkinsonism. Although the pathogenic molecular mechanism of FXTAS is not completely understood, the restriction of the phenotype to the FMR1 premutation range has given rise to a model based on a RNA toxic gain-of-function. Since the identification of the first microRNAs (miRNAs) and their role in normal development, several studies have associated them with neurodegenerative diseases such as Parkinson, Alzheimer and Huntington diseases, suggesting that they play a key role in brain development, as well as in its morphogenesis. Herein, we present the characterization of miRNA expression profiles in FXTAS male patients using deep sequencing-based technologies and microarray technology. Deep sequencing analysis evidenced 83 miRNAs that were significantly deregulated whereas microarray analysis showed 31. When comparing these results, 14 miRNAs were found deregulated in FXTAS patients. MiR-424 and miR-574-3p showed significant fold change adjusted P-values in both platforms in FXTAS patients. MiR-424 has been founded substantially and specifically enriched in human cerebral cortical white matter of Alzheimer disease patients, which, together with cerebral atrophy, is a prominent imaging finding in individuals with FXTAS. The study provides the first systematic evidence of differential miRNA expression changes in FXTAS blood samples. Although further studies are necessary to better characterize the miRNA function in FXTAS disorder, our results suggest that they might contribute to its pathogenesis.


Assuntos
MicroRNAs/sangue , Idoso , Estudos de Casos e Controles , Doenças Cerebelares/diagnóstico , Doenças Cerebelares/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , MicroRNAs/química , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de DNA
2.
Parasitol Res ; 103(3): 587-94, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18509679

RESUMO

Two experiments are described investigating learning and orientation in the triatomine Rhodnius prolixus. In experiment 1, Pavlovian conditioning was investigated. The experiment differed from our previous work in that the intensity of the conditioned and unconditioned stimuli were reduced and the number of training trials increased. Once again, no evidence for Pavlovian conditioning was found. In experiment 2, an "orientation arena" was developed in which the orientation of R. prolixus to a human forearm was investigated when an area of the forearm was impregnated with the odor of ruda or almizcle compared to a forearm with no odor. The various paths of the animal from the bottom of the arena until ascending and piercing the forearm, located at the top of the arena, was scored using a grid system and videotaped. The results indicated that under the no odor condition R. prolixus predominately travels in a straight line from the bottom of the arena to the top where the forearm is located. In contrast, the most variable number of paths occurred with exposure to ruda. Exposure to almizcle elicited straight line paths but other paths were evident, although not as variable as that observed with ruda.


Assuntos
Repelentes de Insetos/farmacologia , Aprendizagem , Locomoção/efeitos dos fármacos , Odorantes , Orientação , Rhodnius/fisiologia , Animais , Antebraço/parasitologia , Humanos , Gravação em Vídeo
3.
Rev. biol. trop ; 52(4): 927-930, dic. 2004. tab
Artigo em Espanhol | LILACS | ID: lil-450787

RESUMO

Se estudió el comportamiento reproductivo y de defecación de Triatoma maculata (Erichson 1848)alimentando artificialmente con sangre humana.Los estadios II y III mostraron mayor frecuencia de defecaciones (ID=0.6 n=40),el estadio V no alcanzó la diferenciación sexual, la fertilidad fue 55%(n=865),fecundidad 8 huevos/hembra/semana (n=26),22 días de desarrollo embrionario (n=477),longevidad de hembras 51 días (n=26),el tiempo intermuda aumenta progresivamente desde 35 días en el estadio I hasta 46 días en el estadio IV,el porcentaje de muda varió desde 0%en el estadio V hasta 63%en el estadio III,la mortalidad varió desde 8%en el estadio III hasta 100%en el estadio V (n=40).Los resultados del presente trabajo aportan evidencias que explican la menor capacidad vectorial y la baja densidad de T.maculata en el domicilio humano


The reproductive and defecating behavior of Triatoma maculata (Erichson 1848)was studied on animals from an university culture in Venezuela.This species does not reach the importance of Rhodnius prolixus Stal 1859 as Chagas disease vector in Venezuela.This study addressed the role of defecating frequency,an index of how dangerous the animals are for the human population,and its relationship with why T.maculata is a less important vector than R.prolixus .Human blood was fed to the insects through an artificial feeding device.The 2nd and 3rd instar nymphs defecated more frequently (Id=0.6,n=40),and our Vth instar nymphs did not complete sexual differentiation.Fertility was 55%(n=865)and fecundity 8 eggs/female/week (n=26). Egg incubation lasted 22 days (n=477).Female longevity was 51 days (n=26).Intermould time grew progressively from 35 days for 1st to 40 days for 4th instar nymphs (n=40).Mould percentage varied from 0% for Vth to 63%for 3rd instar nymphs.Mortality varied from 8% for 3rd to 100% for Vth instar nymphs.These results support evidences explaining the lesser vectorial capacity and low density of T.maculata in human domiciles, including reduced reproduction and defecation when the animal feeds on human blood


Assuntos
Humanos , Animais , Masculino , Feminino , Doença de Chagas/transmissão , Defecação/fisiologia , Comportamento Alimentar/fisiologia , Insetos Vetores/fisiologia , Triatoma/fisiologia , Fertilidade , Insetos Vetores/patogenicidade , Estágios do Ciclo de Vida , Longevidade , Ninfa/fisiologia , Reprodução/fisiologia , Diferenciação Sexual , Fatores de Tempo , Venezuela
4.
Rev Biol Trop ; 52(4): 927-30, 2004 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-17354403

RESUMO

The reproductive and defecating behavior of Triatoma maculata (Erichson 1848) was studied on animals from an university culture in Venezuela. This species does not reach the importance of Rhodnius prolixus Stal 1859 as Chagas disease vector in Venezuela. This study addressed the role of defecating frequency, an index of how dangerous the animals are for the human population, and its relationship with why T. maculata is a less important vector than R. prolixus. Human blood was fed to the insects through an artificial feeding device. The 2nd and 3rd instar nymphs defecated more frequently (Id= 0.6, n=40), and our Vth instar nymphs did not complete sexual differentiation. Fertility was 55% (n=865) and fecundity 8 eggs/female/week (n=26). Egg incubation lasted 22 days (n=477). Female longevity was 51 days (n=26). Intermould time grew progressively from 35 days for 1st to 40 days for 4th instar nymphs (n=40). Mould percentage varied from 0% for Vth to 63% for 3rd instar nymphs. Mortality varied from 8% for 3rd to 100% for Vth instar nymphs. These results support evidences explaining the lesser vectorial capacity and low density of T. maculata in human domiciles, including reduced reproduction and defecation when the animal feeds on human blood.


Assuntos
Doença de Chagas/transmissão , Defecação/fisiologia , Comportamento Alimentar/fisiologia , Insetos Vetores/fisiologia , Triatoma/fisiologia , Animais , Feminino , Fertilidade , Humanos , Insetos Vetores/patogenicidade , Estágios do Ciclo de Vida , Longevidade , Masculino , Ninfa/fisiologia , Reprodução/fisiologia , Diferenciação Sexual , Fatores de Tempo , Venezuela
5.
Mem Inst Oswaldo Cruz ; 96(6): 879-81, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11562719

RESUMO

The complete life cycle of Triatoma flavida, weekly fed on hens, was studied at 28+/-2 degrees C and 80+/-10% RH. Aspects related to hatching, life span, mortality and feeding behavior for each stage of its life cycle were evaluated. The hatching rate observed for 100 eggs was 93% with an average incubation period of 27.2 days. Sixty-two nymphs completed the cycle and the mean egg to adult development time was 230.4 days. Mean duration of 1st, 2nd, 3rd, 4th and 5th instar nymphs was 22.1, 25.3, 36.7, 49.7 and 69.4 days, respectively. The number of blood meals on each nymphal stage varied from 1 to 7. The mortality rate was 6.5% for NI, 23% for NIII and 7.5% for NV nymphs. Mean number of laid eggs per female was 283.1. Adult survival rates were 344.8 +/- 256.4 days for males and 285.3 +/- 201.8 days for females.


Assuntos
Estágios do Ciclo de Vida , Triatoma/crescimento & desenvolvimento , Animais , Animais de Laboratório , Comportamento Alimentar , Feminino , Masculino , Oviposição , Temperatura
6.
Rev. biol. trop ; 49(2): 693-695, Jun. 2001.
Artigo em Espanhol | LILACS | ID: lil-333110

RESUMO

Se estudió el comportamiento alimenticio y de defecación de Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 y R. pictipes Stal, 1872 alimentados artificialmente con sangre humana en condiciones de laboratorio. La ninfa I de todas las especies no defecaron en la primera media hora después de haber iniciado la ingesta. R. pictipes no se acercó a picar en el alimentador artificial aunque si lo hizo cuando el alimento se ofreció directamente sobre el cuerpo humano. Las ninfas y adultos de R. prolixus mostraron índices de defecación (ID) superiores a los correspondientes de las otras especies, y la ninfa III presentó el mayor ID=1.62. La mayoría de individuos de todos los estadíos de desarrollo aceptaron el alimento en un tiempo entre 0 y 3 min y se alimentaron en menos de 15 minutos.


Assuntos
Animais , Humanos , Comportamento Alimentar/fisiologia , Rhodnius , Sangue , Defecação/fisiologia , Fatores de Tempo
7.
Rev. biol. trop ; 49(2): 689-691, Jun. 2001.
Artigo em Espanhol | LILACS | ID: lil-333111

RESUMO

Se observó el efecto de diferentes fracciones de sangre humana sobre la ovipostura (fecundidad), la eclosión (fertilidad) y el ciclo biológico de Rhodnius prolixus Stal 1859 utilizando un alimentador artificial. En los ejemplares alimentados con sangre de hombre, la fecundidad fue mayor que en los alimentados con sangre de mujer. No hubo diferencia significativa en la fertilidad relacionada con la procedencia de las fracciones. En cada estadio se estimaron los tiempos de permanencia y el número de ingestas necesarias para mudar al siguiente estadio ninfal. Los animales alimentados sólo con plasma no completaron el desarrollo ninfal, mientras que los alimentados sólo con glóbulos rojos se desarrollaron hasta el tercer estadio. El ciclo de vida se completó en 129 días en los individuos alimentados con sangre sin fraccionar.


Assuntos
Animais , Humanos , Rhodnius , Sangue , Comportamento Alimentar/fisiologia , Fertilidade , Estágios do Ciclo de Vida
8.
Rev Biol Trop ; 49(2): 693-5, 2001 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11935923

RESUMO

Feeding and defecation behavior of Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 and R. pictipes Stal, 1872, artificially fed on human blood, were studied under laboratory conditions. In all species, first instar nymphs did not defecate in the first 30 minutes after feeding. R. pictipes did not accept artificial feeding but fed directly on humans. Nymph and adult R. prolixus had a higher defecation index (DI) than other species; third instar nymphs had the highest DI = 1.62. In all instars, most individuals accepted the food in 3 Pounds minutes and finished feeding in less than 15 minutes.


Assuntos
Comportamento Alimentar/fisiologia , Rhodnius/fisiologia , Animais , Sangue , Defecação/fisiologia , Humanos , Fatores de Tempo
9.
Rev Biol Trop ; 49(2): 689-91, 2001 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11935922

RESUMO

The effect of several human blood fractions artificially fed to Rhodnius prolixus Stal 1859 on oviposture (fecundity), egg-hatching (fertility) and life cycle was observed. Specimens fed on man's blood were more fecund than those fed with woman's blood. There were no significant differences in fertility related to host sex. The nymphal development time and number of feedings to molt to the following instar were estimated. Animals fed only on blood plasm did not finish nymphal development, while those fed only blood red cells ended their life cycle in the third nymphal instar. Total life cycle lasts 129 days in individuals fed with whole blood.


Assuntos
Rhodnius/fisiologia , Animais , Sangue , Comportamento Alimentar/fisiologia , Fertilidade , Humanos , Estágios do Ciclo de Vida
10.
Mem. Inst. Oswaldo Cruz ; 83(4): 441-6, out.-dez. 1988. tab
Artigo em Espanhol | LILACS | ID: lil-75475

RESUMO

Modificando la frecuencia de oferta de alimento a semanal y quincenal se evaluó estadisticamente la variación de algunos parámetros poblacionales y reproductivos en cuatro cohortes de R. neivai alimentadas en gallina o conejo. Se encontró una relación directa entre la frecuencia de oferta de snagre y la longevidad media, longevidad máxima y esperanza de vida de los adultos en los ejemplares que se alimentaron en gallina. En cambio, en los animales a los cuales se ofreció sangre de conejo quincenalmente, los valores de longevidad media, longevidad máxima y esperanza de vida de los adultos fueron altos, y algo menores en los alimentados semanalmente. El rendimiento reproductivo aumentó y la fertilidad edad-específica mostró una cierta disminución cuando la frecuencia de oferta de alimento fue semanal. Todos los parámetros poblacionales, menos el tiempo generacional, fueron mayores en los ejemplares alimentados semanalmente


Assuntos
Animais , Masculino , Feminino , Comportamento Alimentar , Reprodução , Rhodnius/fisiologia
11.
Mem Inst Oswaldo Cruz ; 83(4): 441-6, 1988.
Artigo em Espanhol | MEDLINE | ID: mdl-3078348

RESUMO

After changing feeding frequency to a weekly and biweekly basis, a statistical evaluation of the variation of some population and reproductive parameters was conducted. It was based on four cohorts experiments of Rhodnius neivai fed on hen or rabbit. We found a direct relationship between blood feeding frequency and the parameters adult average longevity, maximum longevity and life expectancy in the animals fed on hen. On the other hand, in the insect fed biweekly on rabbit, these three values were higher than the registered in the cohorts fed weekly. Reproductive output got bigger and age-specific fertility showed a small decrease when feeding frequency was weekly. Every population parameter, except generation time, was greater in the individuals fed weekly.


Assuntos
Comportamento Alimentar , Reprodução , Rhodnius/fisiologia , Triatominae/fisiologia , Animais , Feminino , Masculino , Dinâmica Populacional
12.
Clin Chim Acta ; 177(1): 1-10, 1988 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-3180483

RESUMO

Previous studies on the pathogenesis of abdominal aortic aneurysms have shown both elastase-like activity in the aortic wall and a decreased elastin content. The present study, using specific radioimmunoassays for pancreatic elastase 2 (IRE2) and cationic trypsin(ogen) (IRCT), investigates the concentrations of these proteases which are known to circulate in blood, in abdominal aortic aneurysms. Aortic specimens were obtained from 32 patients with aneurysms and 21 patients with atherosclerotic occlusive disease. Aortic tissue, obtained at autopsy from young adults, served as controls. Elastase-like activity was 300% and 800% higher, respectively, in aortic homogenates from aneurysms in comparison to occlusive disease and control aortic tissue. This was associated with 1.4-fold higher level of IRE2 and 2.7-fold higher levels of IRCT as compared to occlusive disease. Although there was no significant difference in the aortic collagen concentration among all 3 groups, the elastin content of aneurysmal aorta was 85% and 74% lower, respectively, in comparison to control and occlusive aorta. The results of this investigation demonstrate the presence of pancreatic elastase 2 and cationic trypsin(ogen) in abdominal aortic aneurysmal tissue and suggest that circulating pancreatic proteases contribute to the pathophysiology of aneurysms of the infrarenal aorta.


Assuntos
Aorta Abdominal/enzimologia , Aneurisma Aórtico/enzimologia , Arteriosclerose/enzimologia , Elastase Pancreática/análise , Tripsinogênio/análise , Adulto , Idoso , Aneurisma Aórtico/etiologia , Aneurisma Aórtico/patologia , Arteriosclerose/etiologia , Arteriosclerose/patologia , Elastina/análise , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Elastase Pancreática/metabolismo , Radioimunoensaio , Fatores de Risco , Fumar/efeitos adversos , Tripsinogênio/metabolismo
13.
Mem. Inst. Oswaldo Cruz ; 82(4): 511-24, out.-dez. 1987. ilus, tab
Artigo em Inglês | LILACS | ID: lil-47800

RESUMO

Seguimos seis linhagens de Rhodmius neivai em laboratório para avaliar estatisticamente sua dinâmica populacional. Utilizamos duas fontes de alimentos: galinha e coelho. Determinam a porcentagem de eclosäo dos ovos, mortalidade e tempo de desenvolvimento ninfal, mortalidade idade-específica dos adultos, fecundidade e fertilidade idade-específica das fêmeas. Avaliamos, também, alguns parâmetros populacionais, como expectativa de vida, taxa de reproduçäo, taxa finita de crescimento, valor reprodutivo e distribuiçäo estável de idades. A duraçäo do ciclo de vida foi maior nos alimentados em coelho. A sobrevivência ninfal foi ligeiramente maior nos indivíduos alimentados em galinha. A reproduçäo começou antes nos exemplares alimentados em galinha, mas o rendimento reprodutivo e a duraçäo da oviposiçäo foram maiores nos alimentados em coelho. As taxas intrínseca e finita de crescimento foram maiores nos triatomíneos alimentados em galinha. O tempo geracional foi ligeiramente maior nas linhagens alimentadas em coelho. A taxa de reproduçäo foi muito semelhante com ambas as fontes alimentares, embora ligeiramente maior nos exemplares alimentados em coelho. O valor reprodutivo nos alimentos em coelho foi o dobro do obtivo para os que se alimentavam em galinha


Assuntos
Ração Animal , Rhodnius/crescimento & desenvolvimento , Galinhas , Coelhos
14.
Mem Inst Oswaldo Cruz ; 82(4): 511-24, 1987.
Artigo em Espanhol | MEDLINE | ID: mdl-3333946

RESUMO

A statistical evaluation of the population dynamics of R. neivai is based on six cohorts experiments conducted under controlled laboratory conditions. Two blood sources were offered to animals: rabbit and hen. Egg hatching, nymphal development time and mortality, adult longevity and age-specific mortality, female age-specific fecundity and fertility were determined. In addition, some population parameters were evaluated, such as: life expectancy, intrinsic rate of natural increase, net reproduction rate, finite rate of increase, reproductive value and stable age distribution. Life cycle was longer in the animals fed on rabbit, nymphal survival was slightly higher in the individuals fed on hen. Age of first reproduction was lower in the insects fed on hen, but reproductive output and total number of reproductive weeks were greater in the cohorts fed on rabbit. Intrinsic and finite rate of increase were greater in the animals fed on hen. Generation time was slightly greater in the cohorts fed on rabbit. Net reproduction rate was similar on both blood sources, although it was slightly bigger in the individuals fed on rabbit. Reproductive value in the insects fed on rabbit was twice as much as the registered in the animals fed on hen.


Assuntos
Rhodnius/fisiologia , Triatominae/fisiologia , Análise Atuarial , Animais , Comportamento Alimentar , Feminino , Fertilidade , Expectativa de Vida , Masculino , Dinâmica Populacional
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