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1.
Int J Genomics ; 2015: 407165, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167472

RESUMO

This study was carried out to study the proteome of date palm under salinity and drought stress conditions to possibly identify proteins involved in stress tolerance. For this purpose, three-month-old seedlings of date palm cultivar "Sagie" were subjected to drought (27.5 g/L polyethylene glycol 6000) and salinity stress conditions (16 g/L NaCl) for one month. DIGE analysis of protein extracts identified 47 differentially expressed proteins in leaves of salt- and drought-treated palm seedlings. Mass spectrometric analysis identified 12 proteins; three out of them were significantly changed under both salt and drought stress, while the other nine were significantly changed only in salt-stressed plants. The levels of ATP synthase alpha and beta subunits, an unknown protein and some of RubisCO fragments were significantly changed under both salt and drought stress conditions. Changes in abundance of superoxide dismutase, chlorophyll A-B binding protein, light-harvesting complex1 protein Lhca1, RubisCO activase, phosphoglycerate kinase, chloroplast light-harvesting chlorophyll a/b-binding protein, phosphoribulokinase, transketolase, RubisCO, and some of RubisCO fragments were significant only for salt stress.

2.
Rev. colomb. biotecnol ; 12(2): 223-229, dic. 2010.
Artigo em Espanhol | LILACS | ID: lil-590788

RESUMO

Pilosocereus sp es una especie en peligro crítico de extinción, la única población conocida se encuentra en una mina de mármol verde, hoy abandonada, en la que su explotación produjo la disminución del 80% de la población en 3 años; en la actualidad quedan 28 ejemplares, de ellos unos pocos son adultos, de los cuales solo dos producen frutos. Una de las etapas necesaria para su recuperación es la producción de plántulas para realizar el reforzamiento de la población natural. Como las plantas obtenidas serán plantadas en condiciones naturales, donde se enfrentarán a diversas situaciones ambientales, es conveniente realizar un estudio de diversidad genética. El objetivo de este trabajo fue estimar la variabilidad genética de plántulas de Pilosocereus sp empleando la técnica Inverse Sequence Tagged Repeat (ISTR). Se realizó la germinación in vitro de semillas y se determinó la variabilidad genética de las plántulas obtenidas. Con el análisis molecular se detectaron un total de 97 bandas, de ellas el 62,8% fueron polimórficas. El mayor porcentaje de bandas polimórficas (85,7%) se obtuvo con la combinación de oligonucleótidos F6/B6. Con las combinaciones de oligonucleótidos empleados se detectaron de 4 a 6 patrones de banda diferentes. La heterocigosidad media esperada fue de 0,39.


Pilosocereus sp is a species in critical extinction danger, the only known population is in a mine of green marble, abandoned today, but it exploitation produced the decrease of the population's 80% in 3 years, at the present time they are 28 individuals, of them some few ones are mature, of those which alone two produce fruits. One of the necessary stages for their recovery is the seedlings production to carry out the natural population's reinforcement. As the obtained plants they will be planted under natural conditions, where they will face diverse environmental situations, it is convenient to carry out a study of genetic diversity. The objective of this work was to estimate the genetic variability using the technical Inverse Sequence Tagged Repeat (ISTR). In vitro germination of seeds of Pilosocereus sp and the genetic variability of the obtained seedlings was determined. With the molecular analysis a total of 97 bands were detected, of them 62.8% were polymorphic. The biggest percentage of polymorphism (85.7%) was obtained with the primer combination F6/B6. With the primer combinations employed were detected from 4 to 6 different band patterns. The heterocigocity hoped was 0.39.


Assuntos
Biomarcadores/análise , Cactaceae/classificação , Cactaceae/efeitos adversos , Cactaceae/imunologia , Cactaceae/microbiologia , Cactaceae/química , Cactaceae/ultraestrutura
4.
Rev. colomb. biotecnol ; 12(1): 64-76, jul. 2010. tab, graf
Artigo em Espanhol | LILACS | ID: lil-590646

RESUMO

La familia Myrtaceae ha evolucionado desde las formas más primitivas en los bosques húmedos y lluviosos hasta formas especializadas en regiones semiáridas, muy secas y altamente influenciadas por los cambios estacionales. Aunque los botánicos han estado describiendo estas especies desde hace 200 años, la clasificación de las mismas no está completamente esclarecida. Las Secuencias Simples Repetidas (SSR), conocidas comúnmente como microsatélites, representan una porción significativa del genoma eucariótico y pueden ser de gran utilidad para estos fines. El objetivo del presente trabajo fue utilizar cebadores SSR, diseñados previamente para guayabo, en la identificación de accesiones y en el estudio de diversidad en Myrtaceae. Para este propósito se emplearon cuatro combinaciones de cebadores SSR siguiendo los protocolos establecidos en la literatura. Se realizó el análisis de los resultados atendiendo a la potencialidad de amplificación cruzada, la detección de diferentes alelos, la utilidad para la identificación de accesiones y el estudio de la diversidad y la determinación de las relaciones existentes entre las especies y cultivares en estudio. El alto nivel de polimorfismo detectado por los microsatélites evaluados, el cual se refleja en los valores de los índices relacionados con el nivel de polimorfismo y la capacidad de discriminación calculados, indica las potencialidades de los SSR para la identificación de accesiones en otros representantes de la familia Myrtaceae. Además, representan una herramienta de gran utilidad para estudios de diversidad en esta familia; así como para la estimación de las relaciones de parentesco entre los genotipos analizados, análisis taxonómico y de filogenia.


Myrtaceae family has evolved from primitive forms in rainy and humid forest to specialized forms in semiarid and very dry regions, highly influenced by seasonal changes. Although botanist have been describing Myrtaceae family species over 200 years, classification is far from be completely clarify. Simple Sequences Repeats (SSR), usually known as microsatellites, represent a significant portion of eukaryotic genome and can be of great utility for these purposes. The objective of the present work was to utilize SSR primers, previously designed in guava, for accessions identification and diversity studies of other Myrtaceae members. For this purpose, four SSR primer combinations were utilized following the protocols established in the literature. The results were analyzed attending to cross amplification potentiality, detection of different alleles, utility for accessions identification and diversity studies and relationships determination between the studied species and cultivars. The high level of polymorphism detected by the evaluated microsatellites, which is reflected in the values of each index related with polymorphism and calculated discriminating capacity, indicates the potentials of SSR for accessions identification in other Myrtaceae family members. Also, represents a great utility tool for diversity studies in this family, as well as for the estimation of parentage relationship between the genotypes investigated and the taxonomic and phylogenetic analysis.


Assuntos
Psidium/genética , Psidium/microbiologia , Psidium/química , Filogenia
5.
Rev. colomb. biotecnol ; 12(1): 113-123, jul. 2010. tab, graf
Artigo em Espanhol | LILACS | ID: lil-590650

RESUMO

Los estudios de variabilidad genética resultan útiles para el manejo racional del material, tanto para su conservación como para el mejoramiento. La Repetición de Secuencias Inversas Marcadas (ISTR) es una técnica basada en la PCR que permite el estudio de la diversidad genética de individuos y poblaciones; identificación de cultivares, entre otras aplicaciones. En este sentido, el objetivo del presente trabajo fue estudiar la diversidad de accesiones de guayabo empleando este marcador molecular. Para el análisis de los datos se generó una matriz de ausencia-presencia de las bandas polimórficas, a partir de la cual se desarrolló un análisis de agrupamiento basado en el coeficiente de Jaccard y el método UPGMA para la construcción del dendrograma con el programa NTSYS-pc. La evaluación de los genotipos de guayabo con el marcador ISTR generó un total de 52 bandas polimórficas, las cuales permitieron diferenciar todos los materiales evaluados, corroborando la utilidad de esta técnica para la identificación de accesiones en la especie. El análisis de agrupamiento permitió evidenciar la formación de cuatro grupos de diversidad definidos y la presencia de cuatro accesiones externas. Las diferencias encontradas en el agrupamiento de las accesiones por ISTR respecto a las obtenidas previamente por AFLP y SSR sugieren que el elegir la técnica más apropiada para determinados estudios puede resultar un proceso difícil. Los resultados discutidos en este trabajo indican la necesidad de realizar estudios integrados en el banco de germoplasma de este cultivo para lograr un manejo más racional de la base genética del mismo.


Studies about genetic variability can be useful for material rational management, as much as for conservation and breeding. The Inverse Sequence Tagged Repeats (ISTR) is a technique based on PCR, which permit the study of genetic diversity for individuals and populations; cultivars identification, within other applications. In this sense, the objective of the present work was to study guava accessions diversity using this molecular marker. For data analysis, an absence-presence matrix for polymorphic bands was generated, from which a cluster analysis was developed, based on Jaccard coefficient and UPGMA method for dendrogram construction using NTSYS-pc program. Guava genotypes evaluation with ISTR marker generated a total of 52 polymorphic bands, which permitted to differentiated all the materials evaluated, corroborating the utility of this technique for accessions identification in the specie. Cluster analysis permitted to evidence the formation of four defined diversity groups and the presence of four external accessions. The differences encountered for accessions clustering with ISTR respected to the ones obtained previously for AFLP and SSR suggest that the election of the most appropriated technique for determinate studies can result a difficult process. The results discussed in this work indicate the necessity to made integrated studies on the germplasm bank of this crop to obtain a more adequate management.


Assuntos
Genótipo , Polimorfismo Genético/fisiologia , Polimorfismo Genético/genética , Polimorfismo Genético/imunologia , Psidium/crescimento & desenvolvimento , Psidium/efeitos adversos , Psidium/genética , Psidium/microbiologia , Psidium/química
6.
Rev. colomb. biotecnol ; 11(2): 31-39, dic. 2009.
Artigo em Espanhol | LILACS | ID: lil-550517

RESUMO

Los marcadores moleculares son herramientas valiosas en los estudios genéticos en plantas, y están siendo empleados exitosamente en programas de mejoramiento principalmente en la elección de progenitores y en la selección. El polimorfismo observado mediante la técnica molecular AFLP (Amplified Fragment Length Polymorphism) ha sido de utilidad para estudios de diversidad genética en frutales. En el presente trabajo se realizó la caracterización molecular de 12 accesiones de papaya (Carica papaya L.) del banco de germoplasma del Instituto de Investigaciones en Fruticultura Tropical (IIFT), empleando la técnica AFLP. Se evaluaronseis combinaciones de iniciadores para la amplificación selectiva, las cuales amplificaron un total de 431 bandascon 73,3% de polimorfismo. El número total de patrones de bandas identificados fue igual en todas las combinaciones utilizadas, con un porcentaje de identificación alto, lo que sugiere que dichas combinaciones pudieran ser empleadas para estudios de variabilidad genética en papaya. En general, los resultados presentados demuestran que existe diversidad genética entre las accesiones evaluadas, lo cual constituye un reflejo del origen que presentan los genotipos analizados a partir de la introducción de materiales foráneos y la polinización abierta de un grupo de materiales selectos. Por tanto, se recomienda retomar la prospección y selecciónde accesiones locales, así como la introducción de nuevos genotipos foráneos, como dos vías fundamentalespara aumentar la diversidad genética presente en el banco de germoplasma de papaya de Cuba.


Molecular markers are valuable tools for genetic studies in plants and they are often used successfully in genetic breeding, mainly for choosing progenitors and selection. Polymorphism observed by amplified fragment length polymorphism (AFLP) has been useful for genetic diversity studies in fruit trees. Twelve papaya accessions from the Tropical Fruit Crop Research Institute germplasm bank were molecularly characterised by AFLP. 431 bands having 73.3% polymorphism were obtained using 6 primer combinations. The total number of band patterns identified was the same in all combinations assayed with a high percentage of identification, suggesting that such primer combinations could be used for genetic variability studies in papaya.The results demonstrated genetic diversity among the papaya accessions evaluated, indicating the origin ofthe analysed genotypes from exogenous material and open pollination of a selected group of material. It is thus recommended that local accessions and their selection be monitored as well as the introduction of new foreign genotypes as two ways of increasing the genetic diversity of the Cuban papaya germplasm bank.


Assuntos
Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Antígenos de Superfície , Biomarcadores/análise
7.
Rev. colomb. biotecnol ; 10(2): 6-13, dic. 2008. tab, graf
Artigo em Espanhol | LILACS | ID: lil-505448

RESUMO

Se realizó la caracterización molecular entre 16 ecotipos de cocoteros pertenecientes a una población del municipio de Baracoa, provincia Guantánamo, empleando la técnica Inverse Sequence Tagged Repeat (ISTR). El análisis molecular ISTR detectó un polimorfismo del 81,8 por ciento, demostrando la potencialidad de este marcadorpara realizar estudios de diversidad molecular en el cocotero. El porcentaje de identificación fue alto (Pi=91,2 por ciento), lo cual sugiere que las combinaciones de oligonucleótidos empleadas pudieran ser utilizada para estudios de identificación de ecotipos en poblaciones de cocotero de la zona de Baracoa mientras, que la heterocigocidad esperada fue baja (He=0,30). La evaluación de la diversidad en los diferentes ecotipos de cocoteros mediante marcadores ISTR mostró que se cuenta con un nivel de variabilidad, atendiendo a los grupos formados, lo que se corresponde con la gran variación morfológica observada en la poblaciónin situ. Además, estos resultados sugieren que la hibridación natural ha sido un factor determinante en la generación de la variabilidad encontrada entre los ecotipos, característica de las variedades de cocotero.


Assuntos
Criança , Cocos/genética , Polimorfismo Genético
8.
Scand J Gastroenterol ; 40(10): 1168-75, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16165701

RESUMO

OBJECTIVE: The influence of irradiation on the clinical severity of incontinence, sphincter function, morphologic features and short/long-term treatment effects of sphincter training therapy is still insufficiently understood in irradiated patients with fecal incontinence after surgery for colorectal cancer. These parameters were compared in irradiated and non-irradiated patients and followed prospectively with regard to short- and long-term training effects. MATERIAL AND METHODS: Forty-one patients having been irradiated after surgery (50.0+/-5.0 Gy) and 54 non-irradiated patients with fecal incontinence participated in this prospective, non-randomized trial. Baseline evaluation included a semiquantitative severity assessment score of fecal incontinence (modified Cleveland Incontinence Score (MCIS)), rectal manometry and endoscopy. After 3 weeks (short term) of intensive in-hospital pelvic floor exercise combined with biofeedback training, a second evaluation was made. In addition, anal endosonography (EUS) was performed in cases of treatment failure. After one year (long term) a third evaluation was made clinically (MCIS score). RESULTS: Irradiated patients presented with a significantly higher degree of fecal incontinence (lower MCIS) compared to non-irradiated patients: 7.4+/-2.2 versus 8.7+/-2.7 points (p<0.001). Rectosigmoidal inflammation was more frequent in irradiated than non-irradiated patients (26.9% versus 9.3%) (p<0.03). Sphincter pressure, sensation/pain threshold and the rectoanal inhibitory reflex were similar in both groups. A significant short-term training effect was observed in both groups following sphincter training therapy in terms of an increase in MCIS from 7.4+/-2.2 to 9.4+/-2.7 points in the irradiated group and from 8.7+/-2.7 to 11.4+/-2.5 points in the non-irradiated group (p<0.0001). After one year the scores were 8.2+/-3.8 and 10.7+/-4.4 points, respectively (p<0.0001). There was a significant correlation (p<0.001) between baseline MCIS and the short- and long-term MCIS. In patients with short-term treatment failure (16.6%) anal EUS revealed structural defects of the external sphincter in four patients. There was no association of sphincter diameter with sphincter pressure, sensation/pain threshold and short/long-term MCIS. CONCLUSIONS: The main result of this study is that irradiated patients show short- and long-term training effects comparable with those of non-irradiated patients despite the higher degree of incontinence at baseline. The correlation between the initial MCIS and short- and long-term treatment effects may be regarded as an important clinical predictor for treatment outcome. Functional and morphologic features are less suitable for this purpose.


Assuntos
Biorretroalimentação Psicológica , Neoplasias Colorretais/radioterapia , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Terapia por Exercício , Incontinência Fecal/terapia , Irradiação Hemicorpórea/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/diagnóstico por imagem , Canal Anal/fisiopatologia , Endoscopia Gastrointestinal , Endossonografia , Incontinência Fecal/diagnóstico por imagem , Incontinência Fecal/etiologia , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Diafragma da Pelve/diagnóstico por imagem , Diafragma da Pelve/fisiopatologia , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
9.
Exp Gerontol ; 39(11-12): 1651-60, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15582281

RESUMO

The importance of androgen signaling is well recognized for numerous aspects of central nervous system (CNS) function, ranging from sex-specific organization of neuroendocrine and behavioral circuits to adaptive capacity, resistance and repair. Nonetheless, concepts for the therapeutic use of androgens in neurological and mental disorders are far from being established. This review outlines some critical issues which interfere with decisions on the suitability of androgens as therapeutic agents for CNS conditions. Among these, sex-specific organization of neural substrates and resulting differential responsiveness to endogenous gonadal steroids, convergence of steroid hormone actions on common molecular targets, co-presence of different sex steroid receptors in target neuronal populations, and in situ biotransformation of natural androgens apparently pose the principal obstacles for the characterization of specific neurotropic effects of androgens. Additional important, albeit less explored aspects consist in insufficient knowledge about molecular targets in the CNS which are under exclusive or predominant androgen control. Own experimental data illustrate the variability of pharmacological effects of natural and synthetic androgens on CNS functions of adaptive relevance, such as sexual behavior, anxiety and endocrine responsiveness to stress. Finally, we present results from an analysis of the consequences of aging for the rat brain transcriptome and examination of the influence of androgens on differentially expressed genes with presumable significance in neuropathology.


Assuntos
Androgênios/fisiologia , Encéfalo/metabolismo , Fatores de Crescimento Neural/fisiologia , Transdução de Sinais/fisiologia , Idoso , Envelhecimento , Androgênios/farmacologia , Animais , Humanos , Masculino , Modelos Animais , Ratos , Receptores Androgênicos/metabolismo , Comportamento Sexual , Estresse Psicológico
10.
FASEB J ; 18(13): 1568-70, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15289439

RESUMO

Transient activation of estrogen receptors (ER) in the developing brain during a limited perinatal "window of time" is recognized as a key mechanism of defeminization of neural control of reproductive function and sexual behavior. Two major ER isoforms, alpha and beta, are present in neural circuits that govern ovarian cycle and sexual behavior. Using highly selective ER agonists, this study provides the first evidence for distinct contribution of individual ER isoforms to the process of estrogen dependent defeminization. Neonatal activation of the ERalpha in female rats resulted in abrogation of cyclic ovarian activity and female sexual behavior in adulthood. These effects are associated with male-like alterations in the morphology of the anteroventral periventricular (AVPV) and sexually dimorphic nucleus of the preoptic area (SDN-POA), as well as refractoriness to estrogen-mediated induction of sexual receptivity. Exposure to an ERbeta-selective agonist induced persistent estrus and had a strong defeminizing effect on the hypothalamic gonadotropin "surge generator" AVPV. However, neonatal ERbeta activation failed to alter female sexual behavior, responsiveness to estrogens and morphometric features of the behaviorally relevant SDN-POA. Thus, although co-present in several brain regions involved in the control of female reproductive function, ER isoforms convey different, and probably not synergistic, chemical signals in the course of neonatal sex-specific brain organization.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Receptor alfa de Estrogênio/metabolismo , Caracteres Sexuais , Animais , Animais Recém-Nascidos , Encéfalo/anatomia & histologia , Encéfalo/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/agonistas , Feminino , Ovário/efeitos dos fármacos , Ovário/fisiologia , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/metabolismo , Ratos , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia
11.
Anesthesiology ; 100(5): 1088-100, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15114205

RESUMO

BACKGROUND: Preoperative alteration of T cell-mediated immunity as well as an altered immune response to surgical stress were found in long-term alcoholic patients. The aim of this study was to evaluate perioperative T cell-mediated immune parameters as well as cytokine release from whole blood cells after lipopolysaccharide stimulation and its association with postoperative infections. METHODS: Fifty-four patients undergoing elective surgery of the aerodigestive tract were included in this prospective observational study. Long-term alcoholic patients (n = 31) were defined as having a daily ethanol consumption of at least 60 g and fulfilling the Diagnostic and Statistical Manual of Mental Disorders for either alcohol abuse or alcohol dependence. The nonalcoholic patients (n = 23) were defined as drinking less than 60 g ethanol/day. Blood samples to analyze the immune status were obtained on morning before surgery and on the morning of days 1, 3, and 5 after surgery. RESULTS: Basic patient characteristics did not differ between groups. Before surgery, the T helper 1:T helper 2 ratio (Th1: Th2) was significantly lower (P < 0.01), whereas plasma interleukin 1beta and lipopolysaccharide-stimulated interleukin 1ra from whole blood cells were increased in long-term alcoholic patients. After surgery, a significant suppression of the cytotoxic lymphocyte ratio (Tc1:Tc2), the interferon gamma:interleukin 10 ratio from lipopolysaccharide-stimulated whole blood cells, and a significant increase of plasma interleukin 10 was observed. Long-term alcoholics had more frequent postoperative infections compared with nonalcoholic patients (54%vs. 26%; P = 0.03). CONCLUSIONS: T helper cell-mediated immunity was significantly suppressed before surgery and possibly led to inadequate cytotoxic lymphocyte and whole blood cell response in long-term alcoholic patients after surgery. This altered cell-mediated immunity might have accounted for the increased infection rate in long-term alcoholic patients after surgery.


Assuntos
Alcoolismo/imunologia , Alcoolismo/cirurgia , Complicações Pós-Operatórias/imunologia , Infecção da Ferida Cirúrgica/imunologia , Alcoolismo/tratamento farmacológico , Antibioticoprofilaxia , Cefuroxima/farmacologia , Cefuroxima/uso terapêutico , Citocinas/metabolismo , Feminino , Humanos , Imunidade Celular/efeitos dos fármacos , Masculino , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Prospectivos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
12.
Clin Pharmacokinet ; 43(4): 267-78, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15005635

RESUMO

BACKGROUND: The oral hypoglycaemic drug nateglinide is eliminated from the human body via hepatic biotransformation and renal tubular secretion. According to in vitro data, about 70% of nateglinide intrinsic clearance may be mediated by cytochrome P450 (CYP) 2C9 and a smaller fraction by CYP3A4 and CYP2D6. OBJECTIVE: To assess the impact of CYP2C9 polymorphisms and of the CYP2D6 poor metaboliser genotype on the pharmacokinetics of nateglinide and its effects on insulin, glucose and glucagon in plasma. DESIGN AND PARTICIPANTS: A prospective clinical study in 26 healthy volunteers chosen for their CYP2C9 and CYP2D6 genotype was conducted with individuals carrying wild-type genotype as reference group. METHODS: Serial plasma nateglinide, glucose, insulin and glucagon concentrations were measured over 34 hours after a 180 mg dose of nateglinide under challenge with 75 g of oral glucose at 0, 4 and 8 hours after nateglinide intake. Kinetics were evaluated by nonparametric methods and by population pharmacokinetic-pharmacodynamic modelling. RESULTS: Significantly reduced oral nateglinide clearance was found in carriers of CYP2C9*3 alleles, (p < 0.01), whereas carriers of CYP2C9*2 alleles had kinetic parameters similar to those of carriers of the wild-type allele (p = nonsignificant). Median total clearances were 7.9, 8.4, 6.5, 6.9, 5.8 and 4.1 L/h in carriers of the CYP2C9 genotypes *1/*1, *1/*2, *2/*2, *1/*3, *2/*3 and *3/*3. Median clearance in three carriers of two deficient CYP2D6 alleles was 9.4 L/h. These differences in nateglinide kinetics due to CYP2C9 genotypes did not result in statistically significant differences in plasma glucose, insulin and glucagon. Pharmacokinetic-pharmacodynamic modelling revealed a minor effect of CYP2C9 genotype on insulin and glucose, and extrapolations indicated that carriers of the CYP2C9*3/*3 genotype may be at a slightly higher risk of hypoglycaemia compared with carriers of CYP2C9*1, particularly when taking nateglinide doses above 120 mg. CONCLUSION: The effect of CYP2C9 polymorphisms on nateglinide kinetics may cause a slightly increased risk for hypoglycaemia, which may become relevant in diabetic patients.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Cicloexanos/farmacocinética , Citocromo P-450 CYP2D6/genética , Hipoglicemiantes/farmacocinética , Fenilalanina/farmacocinética , Adulto , Alelos , Hidrocarboneto de Aril Hidroxilases/metabolismo , Glicemia/efeitos dos fármacos , Cicloexanos/farmacologia , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP2D6/metabolismo , Feminino , Genótipo , Glucagon/sangue , Humanos , Hipoglicemiantes/farmacologia , Insulina/sangue , Masculino , Taxa de Depuração Metabólica , Nateglinida , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Polimorfismo Genético , Estudos Prospectivos
13.
Proc Natl Acad Sci U S A ; 100(15): 8939-44, 2003 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-12835413

RESUMO

Potato leafroll polerovirus (PLRV) genomic RNA acts as a polycistronic mRNA for the production of proteins P0, P1, and P2 translated from the 5'-proximal half of the genome. Within the P1 coding region we identified a 5-kDa replication-associated protein 1 (Rap1) essential for viral multiplication. An internal ribosome entry site (IRES) with unusual structure and location was identified that regulates Rap1 translation. Core structural elements for internal ribosome entry include a conserved AUG codon and a downstream GGAGAGAGAGG motif with inverted symmetry. Reporter gene expression in potato protoplasts confirmed the internal ribosome entry function. Unlike known IRES motifs, the PLRV IRES is located completely within the coding region of Rap1 at the center of the PLRV genome.


Assuntos
Luteovirus/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Códon de Iniciação/genética , Genoma Viral , Luteovirus/isolamento & purificação , Luteovirus/fisiologia , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA Viral/genética , Sequências Repetitivas de Ácido Nucleico , Ribossomos/genética , Homologia de Sequência de Aminoácidos , Solanum tuberosum/virologia , Replicação Viral/genética
14.
Plant J ; 34(6): 813-26, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12795701

RESUMO

In the dominant mutant Hooded (K), the barley gene BKn3 is overexpressed as a result of a duplication of 305 bp in intron IV. When fused to a cauliflower mosaic virus 35S minimal promoter, the 305 bp element activates gene expression in tobacco, as does a 655 bp BKn3 promoter sequence. Both DNA fragments contain a (GA)8 repeat (GA/TC)8. A one-hybrid screen using the 305 bp element as the DNA target led to the cloning of the barley b recombinant (BBR) protein, which binds specifically to the (GA/TC)8 repeat. BBR is nuclear targeted and is a characterized nuclear localization signal (NLS) sequence, a DNA-binding domain extended up to 90 aa at the C-terminus and a putative N-terminal activation domain. The corresponding gene has no introns and is ubiquitously expressed in barley tissues. In co-transfection experiments, BBR activates (GA/TC)8-containing promoters, and its overexpression in tobacco leads to a pronounced leaf shape modification. BBR has properties of a GAGA-binding factor, but the corresponding gene has no sequence homology to Trl and Psq of Drosophila, which encode functionally analogous proteins. In Arabidopsis, (GA/TC)8 repeats occur particularly within 1500 bp upstream of gene start codons included in some homeodomain genes of different classes. The data presented suggest that expression of the barley BKn3 is regulated, at least in part, by the binding of the transcription factor BBR to GA/TC repeats.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes Homeobox/genética , Genes de Plantas/genética , Hordeum/genética , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Biologia Computacional , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos/genética , Íntrons/genética , Dados de Sequência Molecular , Sinais de Localização Nuclear , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Ativação Transcricional , Leveduras
15.
Horm Behav ; 43(2): 293-301, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12694639

RESUMO

Implicit motives for power and affiliation, salivary levels of testosterone, estradiol, and progesterone, and relationship status were measured in 18 normally cycling (NC) women, 18 women using oral contraceptives (OC), and 18 men at three assessments, corresponding to the menstrual, midcycle, and premenstrual phases of women's menstrual cycle. NC and OC women had elevated levels of affiliation motivation and decreased levels of power motivation at midcycle. Power motive changes were particularly pronounced in NC women across cycle phases. OC women and participants not engaged in an intimate relationship had significantly heightened levels of affiliation motivation, averaged across all cycle phases. Testosterone and power motivation, both averaged across all cycle phases, were positively correlated in men and in single women, but not in women engaged in an intimate relationship. Averaged levels of estradiol and power motivation were positively correlated in engaged women, but not in single women or men. Averaged levels of progesterone and affiliation motivation were negatively correlated in men, and there was evidence for a positive association between luteal affiliation motivation and periovulatory and luteal progesterone in NC women. This study therefore provides evidence that implicit motivational states fluctuate across the menstrual cycle, that the power motive is associated with testosterone and, in women, with estradiol, and that the affiliation motive and progesterone are associated in different ways in men and NC women.


Assuntos
Hormônios Esteroides Gonadais/metabolismo , Ciclo Menstrual/psicologia , Motivação , Poder Psicológico , Comportamento Social , Análise de Variância , Anticoncepcionais Orais/farmacologia , Estradiol/análise , Estradiol/metabolismo , Feminino , Hormônios Esteroides Gonadais/análise , Humanos , Masculino , Estado Civil , Ciclo Menstrual/efeitos dos fármacos , Ciclo Menstrual/metabolismo , Progesterona/análise , Progesterona/metabolismo , Saliva/química , Caracteres Sexuais , Testosterona/análise , Testosterona/metabolismo
16.
Proc Natl Acad Sci U S A ; 99(21): 13681-6, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12271144

RESUMO

The cytokine macrophage migration inhibitory factor (MIF) exerts a multitude of biological functions. Notably, it induces inflammation at the interface between the immune system and the hypothalamus-pituitary-adrenal stress axis. The role of MIF in infectious diseases is not understood completely. Here, we show that MIF-deficient (MIF(-/-)) knockout mice fail to control an infection with wild-type Salmonella typhimurium. Increased susceptibility was accompanied by a reduced Th1 response, demonstrated by decreased levels of IL-12, IFNgamma, and tumor necrosis factor alpha. In Salmonella-infected MIF(-/-) mice, levels of IL-1beta were markedly increased. Additionally, infected MIF(-/-) mice showed elevated serum levels of nitric oxide and corticosterone as compared with control mice. Our results point to MIF as a key mediator in the host response to S. typhimurium. MIF not only promotes development of a protective Th1 response but ameliorates disease by altering levels of reactive nitrogen intermediates and corticosteroid hormones, which both exert immunosuppressive functions.


Assuntos
Fatores Inibidores da Migração de Macrófagos/imunologia , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Animais , Corticosterona/sangue , Mediadores da Inflamação/metabolismo , Interferon gama/biossíntese , Interleucina-12/biossíntese , Fatores Inibidores da Migração de Macrófagos/deficiência , Fatores Inibidores da Migração de Macrófagos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/biossíntese , Infecções por Salmonella/sangue , Salmonella typhimurium/patogenicidade , Células Th1/imunologia , Fator de Necrose Tumoral alfa/biossíntese
17.
Clin Pharmacol Ther ; 71(4): 286-96, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11956512

RESUMO

BACKGROUND: Glyburide (INN, glibenclamide) is a second-generation sulfonylurea antidiabetic agent with high potency. We hypothesized that glyburide may be a substrate of cytochrome P450 2C9 (CYP2C9), an enzyme that has two low-activity amino acid variants-Arg144Cys (CYP2C9*2) and Ile359Leu (CYP2C9*3). We explored the impact of these polymorphisms on glyburide pharmacokinetics and the effects on insulin and glucose concentrations. METHODS: Twenty-one healthy volunteers who represented all possible combinations of the two variant alleles were studied (genotypes CYP2C9*1/*1, *1/*2, *2/*2, *1/*3, *2/*3, and *3/*3 ). They received a single oral dose of 3.5 mg glyburide followed by 75 g glucose at 1, 4.5, and 8 hours after administration of glyburide. Glyburide was quantified in plasma by reversed-phase HPLC. Venous blood concentrations of glyburide, insulin, and glucose were analyzed with a population pharmacokinetic-pharmacodynamic model by use of NONMEM statistical software. RESULTS: Pharmacokinetics of glyburide depended significantly on CYP2C9 genotypes. In homozygous carriers of the genotype *3/*3, total oral clearance was less than half of that of the wild-type genotype *1/*1 (P <.001). Correspondingly, insulin secretion measured within 12 hours after glyburide ingestion was higher in carriers of the genotype *3/*3 compared with the other genotypes (P =.028), whereas the differences in glucose concentrations were not significant. CONCLUSIONS: Carriers of the CYP2C9 variant *3 had decreased oral clearances of glyburide. This confirms that glyburide is metabolized by CYP2C9. Corresponding differences in insulin plasma levels indicated that dose adjustment based on CYP2C9 genotype may improve antidiabetic treatment.


Assuntos
Aminoácidos/genética , Hidrocarboneto de Aril Hidroxilases , Glicemia/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Glibureto/farmacocinética , Insulina/sangue , Polimorfismo Genético/genética , Esteroide 16-alfa-Hidroxilase , Esteroide Hidroxilases/genética , Adulto , Alelos , Análise de Variância , Área Sob a Curva , Biotransformação , Citocromo P-450 CYP2C9 , Avaliação de Medicamentos/métodos , Avaliação de Medicamentos/estatística & dados numéricos , Genótipo , Glibureto/sangue , Humanos , Hipoglicemiantes/sangue , Hipoglicemiantes/farmacocinética , Masculino
18.
Crit Care Med ; 30(1): 107-12, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11902251

RESUMO

OBJECTIVE: Renal failure after bypass is still a threatening problem prolonging hospital care and reducing overall survival. The following pilot study was aimed to analyze whether perioperative low-dose prostacyclin infusion is able to preserve renal function in a selected group of patients who according to a poor cardiac function were stratified as high risk for the development of renal failure after bypass. DESIGN: Prospective randomized study. SETTING: Tertiary care university medical center. PATIENTS: Thirty-four patients scheduled for primary cardiac bypass surgery were included in the study (prostacyclin n = 17, control n = 17). Inclusion criteria were normal renal function before surgery and a cardiac ejection fraction <40%. INTERVENTIONS: Low-dose prostacyclin (2 ng/kg/min) was added to the standard anesthetic protocol. Infusion was started immediately before surgery and was continued for a maximum of 48 MEASUREMENTS AND MAIN RESULTS: Significant differences in the endogenous creatinine clearance were found between the prostacyclin and the control group. Whereas there was a significant drop in the creatinine clearance at 6 hrs after surgery in the control group with a prolonged recovery period, values in the prostacyclin group remained stable. Creatinine clearance before intervention was 100 +/- 22 mL/min in the control group and 91 +/- 22 mL/min in the prostacyclin group, values at 24 hr were 68 +/- 34 mL/min vs. 103 +/- 37 mL/min, respectively (p < .01). Significant findings in favor for the prostacyclin group were also found for urine output and the fractional excretion rate of sodium. CONCLUSION: This first pilot study indicates that low-dose prostacyclin may be of substantial value for preserving renal function in high-risk patients after coronary bypass surgery.


Assuntos
Ponte de Artéria Coronária , Epoprostenol/administração & dosagem , Rim/efeitos dos fármacos , Creatinina/metabolismo , Feminino , Humanos , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos
19.
Pharmacogenetics ; 12(2): 101-9, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11875364

RESUMO

Tolbutamide is known to be metabolized by cytochrome P450 2C9 (CYP2C9), and the effects of the CYP2C9 amino acid polymorphisms *2 (Arg144Cys) and *3 (Ile359Leu) could be important for drug treatment with tolbutamide and for use of tolbutamide as a CYP2C9 test drug. Tolbutamide pharmacokinetics and plasma insulin and glucose concentrations were studied in 23 healthy volunteers with all six combinations of the CYP2C9 alleles *1, *2 and *3, including two subjects with the combined CYP2C9*1/*1 and CYP2C19*2/*2 genotype. Volunteers received a single oral dose of 500 mg tolbutamide, followed by 75 g oral glucose at 1, 4.5 and 8 h after tolbutamide administration. Pharmacokinetic analysis was performed using a computer program for regression analysis of nonlinear mixed effects models. The mean oral clearances of tolbutamide were 0.97 (95% confidence interval [CI] 0.89-1.05), 0.86 (95% CI 0.79-0.93), 0.75 (95% CI 0.69-0.81), 0.56 (95% CI 0.51-0.61), 0.45 (95% CI 0.41-0.49) and 0.15 (95% CI 0.14-0.16) l/h in carriers of CYP2C9 genotypes 1/*1, *1/*2, *2/*2, *1/*3, *2/*3 and *3/*3, respectively. Tolbutamide pharmacokinetics in carriers of the functionally deficient CYP2C19*2/*2 genotype were not different from those in the CYP2C19 highly active genotype. Elimination in the six CYP2C9 genotype groups could be expressed as the linear combination of three constants (0.05, 0.04, 0.01 h(-1), which were specific to the respective CYP2C9 alleles *1, *2 and *3, thus indicating a co-dominant mode of inheritance. Insulin and glucose concentration-time curves did not change with differing CYP2C9 genotypes. Tolbutamide was confirmed as a substrate of the genetically polymorphic enzyme CYP2C9. The pronounced differences in pharmacokinetics due to the amino acid variants did not significantly affect plasma insulin and glucose concentrations in healthy volunteers.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Glicemia/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Hipoglicemiantes/farmacocinética , Oxigenases de Função Mista/genética , Polimorfismo Genético/genética , Esteroide 16-alfa-Hidroxilase , Esteroide Hidroxilases/genética , Tolbutamida/análogos & derivados , Tolbutamida/farmacocinética , Adulto , Alelos , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2C9 , Avaliação de Medicamentos , Feminino , Genótipo , Humanos , Insulina/sangue , Masculino , Vigilância da População , Fatores de Tempo
20.
Horm Behav ; 41(2): 195-202, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11855904

RESUMO

This study tested the hypothesis that implicit power motivation moderates men's testosterone responses to victory or defeat in a contest situation. It also explored to what extent postvictory testosterone increases are associated with enhanced implicit learning of behavior instrumental for winning a contest. Salivary testosterone levels were assessed in 66 male adults several times before and after a contest whose outcome (winning or losing against a competitor on an implicit learning task) was varied experimentally. Among participants low in activity inhibition, a measure of impulse control, the power motive was a significant positive predictor of testosterone increases (15 min postcontest; r = 0.71, P = 0.01) and implicit learning (r = 0.68, P < 0.05) after a victory, whereas it was a significant negative predictor of implicit learning (r = -0.58, P = 0.01) but not of testosterone increases (r = -0.08, ns) after a defeat. Moreover, among participants low in activity inhibition testosterone increases were associated with enhanced implicit learning (r = 0.38, P < 0.05) and there was statistical evidence that in winners testosterone increases mediated the effect of power motivation on implicit learning. Participants high in activity inhibition did not display this pattern of results.


Assuntos
Comportamento Competitivo/fisiologia , Aprendizagem/fisiologia , Motivação , Testosterona/sangue , Adulto , Conscientização/efeitos dos fármacos , Humanos , Masculino , Personalidade/fisiologia , Desempenho Psicomotor/fisiologia , Saliva/metabolismo
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