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1.
Mol Plant Microbe Interact ; 31(10): 1069-1074, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29697298

RESUMEN

Cochliobolus victoria, the causal agent of Victoria blight, is pathogenic due to its production of a toxin called victorin. Victorin sensitivity in oats, barley, Brachypodium spp., and Arabidopsis has been associated with nucleotide-binding site leucine-rich repeat (NLR) genes, a class of genes known for conferring disease resistance. In this work, we investigated the sensitivity of Phaseolus vulgaris to victorin. We found that victorin sensivity in Phaseolus vulgaris is a developmentally regulated, quantitative trait. A single quantitative trait locus (QTL) accounted for 34% of the phenotypic variability in victorin sensitivity among Stampede × Red Hawk (S×R) recombinant inbred lines. We cloned two NLR-encoding genes within this QTL and showed one, Phvul05G031200 (PvLOV), confers victorin-dependent cell death when overexpressed in Nicotiana benthamiana. Protein sequences of PvLOV from victorin-sensitive and the victorin-resistant bean parents differ by two amino acids in the leucine-rich repeat region, but both proteins confer victorin-dependent cell death when overexpressed in N. benthamiana.


Asunto(s)
Regulación de la Expresión Génica de las Plantas/fisiología , Phaseolus/genética , Reacción en Cadena de la Polimerasa , Sitios de Carácter Cuantitativo , Transformación Genética
2.
Genet Mol Res ; 14(3): 8181-200, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26345744

RESUMEN

Gene expression related to drought response in the leaf tissues of two Brazilian upland cultivars, the drought-tolerant Douradão and the drought-sensitive Primavera, was analyzed. RNA-seq identified 27,618 transcripts in the Douradão cultivar, with 24,090 (87.2%) homologous to the rice database, and 27,221 transcripts in the Primavera cultivar, with 23,663 (86.9%) homologous to the rice database. Gene-expression analysis between control and water-deficient treatments revealed 493 and 1154 differentially expressed genes in Douradão and Primavera cultivars, respectively. Genes exclusively expressed under drought were identified for Douradão, including two genes of particular interest coding for the protein peroxidase precursor, which is involved in three distinct metabolic pathways. Comparisons between the two drought-exposed cultivars revealed 2314 genes were differentially expressed (978 upregulated, 1336 downregulated in Douradão). Six genes distributed across 4 different transcription factor families (bHLH, MYB, NAC, and WRKY) were identified, all of which were upregulated in Douradão compared to Primavera during drought. Most of the genes identified in Douradão activate metabolic pathways responsible for production of secondary metabolites and genes coding for enzymatically active signaling receptors. Quantitative PCR validation showed that most gene expression was in agreement with computational prediction of these transcripts. The transcripts identified here will define molecular markers for identification of Cis-acting elements to search for allelic variants of these genes through analysis of polymorphic SNPs in GenBank accessions of upland rice, aiming to develop cultivars with the best combination of these alleles, resulting in materials with high yield potential in the event of drought during the reproductive phase.


Asunto(s)
Adaptación Fisiológica/genética , Sequías , Ecotipo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oryza/genética , Oryza/fisiología , Clima Tropical , Secuencia de Bases , Regulación hacia Abajo/genética , Perfilación de la Expresión Génica , Ontología de Genes , Redes y Vías Metabólicas/genética , Anotación de Secuencia Molecular , Hojas de la Planta/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Estrés Fisiológico/genética , Factores de Transcripción/metabolismo , Regulación hacia Arriba/genética
3.
Theor Appl Genet ; 126(9): 2245-55, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23760652

RESUMEN

Anthracnose (ANT) and angular leaf spot (ALS) are devastating diseases of common bean (Phaseolus vulgaris L.). Ouro Negro is a highly productive common bean cultivar, which contains the Co-10 and Phg-ON genes for resistance to ANT and ALS, respectively. In this study, we performed a genetic co-segregation analysis of resistance to ANT and ALS using an F2 population from the Rudá × Ouro Negro cross and the F2:3 families from the AND 277 × Ouro Negro cross. Ouro Negro is resistant to races 7 and 73 of the ANT and race 63-39 of the ALS pathogens. Conversely, cultivars AND 277 and Rudá are susceptible to races 7 and 73 of ANT, respectively. Both cultivars are susceptible to race 63-39 of ALS. Co-segregation analysis revealed that Co-10 and Phg-ON were inherited together, conferring resistance to races 7 and 73 of ANT and race 63-39 of ALS. The Co-10 and Phg-ON genes were co-segregated and were tightly linked at a distance of 0.0 cM on chromosome Pv04. The molecular marker g2303 was linked to Co-10 and Phg-ON at a distance of 0.0 cM. Because of their physical linkage in a cis configuration, the Co-10 and Phg-ON resistance alleles are inherited together and can be monitored with great efficiency using g2303. The close linkage between the Co-10 and Phg-ON genes and prior evidence are consistent with the existence of a resistance gene cluster at one end of chromosome Pv04, which also contains the Co-3 locus and ANT resistance quantitative trait loci. These results will be very useful for breeding programs aimed at developing bean cultivars with ANT and ALS resistance using marker-assisted selection.


Asunto(s)
Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Phaseolus/genética , Phaseolus/microbiología , Enfermedades de las Plantas/genética , Alelos , Cruzamiento , Colletotrichum , Cruzamientos Genéticos , ADN de Plantas/genética , Genes de Plantas , Ligamiento Genético , Marcadores Genéticos , Interacciones Huésped-Patógeno/genética , Familia de Multigenes , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/microbiología , Sitios de Carácter Cuantitativo , Lugares Marcados de Secuencia
4.
Heredity (Edinb) ; 110(3): 267-76, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23169559

RESUMEN

Wild common bean (Phaseolus vulgaris L.) is distributed throughout the Americas from Mexico to northern Argentina. Within this range, the species is divided into two gene pools (Andean and Middle American) along a latitudinal gradient. The diversity of 24 wild common bean genotypes from throughout the geographic range of the species was described by using sequence data from 13 loci. An isolation-migration model was evaluated using a coalescent analysis to estimate multiple demographic parameters. Using a Bayesian approach, Andean and Middle American subpopulations with high percentage of parentages were observed. Over all loci, the Middle American gene pool was more diverse than the Andean gene pool (π(sil)=0.0089 vs 0.0068). The two subpopulations were strongly genetically differentiated over all loci (F(st)=0.29). It is estimated that the two current wild gene pools diverged from a common ancestor ∼111 000 years ago. Subsequently, each gene pool underwent a bottleneck immediately after divergence and lasted ∼40 000 years. The Middle American bottleneck population size was ∼46% of the ancestral population size, whereas the Andean was 26%. Continuous asymmetric gene flow was detected between the two gene pools with a larger number of migrants entering Middle American gene pool from the Andean gene pool. These results suggest that because of the complex population structure associated with the ancestral divergence, subsequent bottlenecks in each gene pool, gene pool-specific domestication and intense selection within each gene pool by breeders; association mapping would best be practised within each common bean gene pool.


Asunto(s)
ADN de Plantas/genética , Flujo Génico , Pool de Genes , Variación Genética , Phaseolus/genética , Hojas de la Planta/genética , Secuencia de Bases , Teorema de Bayes , ADN de Plantas/clasificación , Sitios Genéticos , Especiación Genética , Genotipo , América Latina , Datos de Secuencia Molecular , Phaseolus/clasificación , Filogenia , Filogeografía , Dispersión de las Plantas , Hojas de la Planta/clasificación
5.
Theor Appl Genet ; 122(5): 893-903, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21113774

RESUMEN

The Andean common bean AND 277 has the Co-1(4) and the Phg-1 alleles that confer resistance to 21 and eight races, respectively, of the anthracnose (ANT) and angular leaf spot (ALS) pathogens. Because of its broad resistance spectrum, Co-1(4) is one of the main genes used in ANT resistance breeding. Additionally, Phg-1 is used for resistance to ALS. In this study, we elucidate the inheritance of the resistance of AND 277 to both pathogens using F(2) populations from the AND 277 × Rudá and AND 277 × Ouro Negro crosses and F(2:3) families from the AND 277 × Ouro Negro cross. Rudá and Ouro Negro are susceptible to all of the above races of both pathogens. Co-segregation analysis revealed that a single dominant gene in AND 277 confers resistance to races 65, 73, and 2047 of the ANT and to race 63-23 of the ALS pathogens. Co-1(4) and Phg-1 are tightly linked (0.0 cM) on linkage group Pv01. Through synteny mapping between common bean and soybean we also identified two new molecular markers, CV542014(450) and TGA1.1(570), tagging the Co-1(4) and Phg-1 loci. These markers are linked at 0.7 and 1.3 cM, respectively, from the Co-1(4) /Phg-1 locus in coupling phase. The analysis of allele segregation in the BAT 93/Jalo EEP558 and California Dark Red Kidney/Yolano recombinant populations revealed that CV542014(450) and TGA1.1(570) segregated in the expected 1:1 ratio. Due to the physical linkage in cis configuration, Co-1(4) and Phg-1 are inherited together and can be monitored indirectly with the CV542014(450) and TGA1.1(570) markers. These results illustrate the rapid discovery of new markers through synteny mapping. These markers will reduce the time and costs associated with the pyramiding of these two disease resistance genes.


Asunto(s)
Mapeo Cromosómico , Genes de Plantas , Phaseolus/genética , Enfermedades de las Plantas/prevención & control , Colletotrichum/patogenicidad , Cruzamientos Genéticos , Ligamiento Genético , Sitios Genéticos , Marcadores Genéticos , Inmunidad Innata , Phaseolus/inmunología , Phaseolus/microbiología , Hojas de la Planta
6.
Diabetes Obes Metab ; 11(6): 603-10, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19515180

RESUMEN

AIM: Enzyme-resistant glucagon-like peptide-1 (GLP-1) receptor agonists and GIP receptor antagonists have been proposed to have therapeutic potential for the treatment of type 2 diabetes. Such benefits are based on actions mediated primarily through stimulation of insulin secretion or alleviation of insulin resistance respectively. This study examined the long-term actions of the stable GLP-1 receptor agonist (D-Ala(8))GLP-1 and the GIP receptor antagonist (Pro(3))GIP alone and in combination in high fat-fed mice. METHODS: Mice on high-fat diet for 155 days were injected once daily with (D-Ala(8))GLP-1 or (Pro(3))GIP (25 nmol/kg body weight) for 24 days. In the following 24-day period, half of the (Pro(3))GIP-treated mice were administered an additional dose of (D-Ala(8))GLP-1 (25 nmol/kg body weight), while the remaining mice continued their original treatment regimes. RESULTS: Daily intraperitoneal injections of (D-Ala(8))GLP-1 or (Pro(3))GIP restored glycaemic control to normal levels and significantly (p < 0.05) improved glucose tolerance compared with high-fat controls by day 24. Food intake and body weights were not affected. On day 48, all treatment groups displayed significantly improved glucose tolerance (p < 0.05) and insulin sensitivity (p < 0.001) compared with high-fat controls on day 48. HDL cholesterol levels were significantly increased in mice treated with (D-Ala(8))GLP-1 alone (p < 0.05) or in combination with (Pro(3))GIP (p < 0.01) compared with normal chow-fed controls. CONCLUSIONS: These results illustrate efficacy of (Pro(3))GIP and (D-Ala(8))GLP-1 for treatment of glucose intolerance and insulin resistance caused by high-fat feeding. Combination therapy appeared to have little benefit over either treatment alone.


Asunto(s)
Polipéptido Inhibidor Gástrico/farmacología , Péptido 1 Similar al Glucagón/farmacología , Receptores de Glucagón/metabolismo , Animales , Glucemia/análisis , Grasas de la Dieta/administración & dosificación , Quimioterapia Combinada , Femenino , Polipéptido Inhibidor Gástrico/administración & dosificación , Péptido 1 Similar al Glucagón/administración & dosificación , Receptor del Péptido 1 Similar al Glucagón , Intolerancia a la Glucosa/metabolismo , Inyecciones Intraperitoneales , Insulina/sangre , Resistencia a la Insulina/fisiología , Ratones , Receptores de la Hormona Gastrointestinal/antagonistas & inhibidores , Receptores de Glucagón/agonistas , Receptores de Glucagón/antagonistas & inhibidores , Resultado del Tratamiento
8.
Diabetes Obes Metab ; 10(4): 336-42, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18333892

RESUMEN

AIM: Glucose-dependent insulinotropic polypeptide-receptor (GIP-R) antagonism using (Pro3)GIP improves glucose tolerance and ameliorates insulin resistance and abnormalities of islet structure and function in a commonly used model of obesity-diabetes, namely ob/ob mice. The effect of GIP-R antagonism in a streptozotocin (STZ)-induced model of insulin deficiency has not been evaluated. The present study has investigated the effects of daily administration of (Pro(3))GIP to STZ-treated mice. METHODS: Swiss TO mice received once-daily injection of (Pro3)GIP (25 nmol/kg body weight) or saline 4 days prior to and 16 days after injection of STZ, and effects on metabolic parameters and islet architecture were assessed. RESULTS: (Pro3)GIP treatment had no significant effect on hyperphagia or body weight loss. However, hyperglycaemia and glycated haemoglobin were worsened, glucose tolerance further decreased and insulin sensitivity was impaired by (Pro3)GIP. These effects were observed on an STZ-induced background characterized by severe reductions of circulating insulin, beta-cell mass and pancreatic insulin stores. CONCLUSIONS: These data indicate that the beneficial actions of the GIP-R antagonist, (Pro3)GIP, in obesity-diabetes appear to be largely mediated through insulin-dependent mechanisms that merit further investigation.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Polipéptido Inhibidor Gástrico/uso terapéutico , Insulina/sangre , Receptores de la Hormona Gastrointestinal/antagonistas & inhibidores , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/patología , Glucagón/uso terapéutico , Hemoglobina Glucada/análisis , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/patología , Masculino , Ratones , Ratones Endogámicos , Modelos Animales , Distribución Aleatoria , Somatostatina/uso terapéutico
9.
Pediatr Transplant ; 12(6): 696-700, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18786070

RESUMEN

Tailoring graft size to small paediatric recipients is a challenge. We have developed a reduced left lateral segment as an alternative to monosegment transplantation for small size recipients. Since November 2000, 89 children have been transplanted with 100 deceased donor liver grafts in our unit. Our median patient and graft survival is 89% and 88% respectively. Four of these cases were performed using a new technique of creating a small donor graft by reducing the left lateral segment. The median weight of the reduced liver graft was 264 g (range: 165-390 g). The median blood transfusion requirement was 101 mL/kg body weight (range 69-167 mL/kg). The median values of peak ALT were 1473 IU/L, INR 2.2 and bilirubin 293 micromol/L in the first two wk following surgery. One neonatal recipient died five days after transplantation from a massive intracranial haemorrhage despite satisfactory graft function. Another recipient with excellent graft function died 10 months later from primary pulmonary hypertension and secondary cardiac failure. Hepatic artery thrombosis occurred in one patient with successful revascularization but he was retransplanted three months later for chronic rejection. No biliary or venous outflow complications occurred in this group. This technique of reduced left lateral segment liver transplantation is an alternative to the monosegment graft and allows small recipients to be successfully transplanted with few technical complications related to graft preparation.


Asunto(s)
Trasplante de Hígado/efectos adversos , Trasplante de Hígado/métodos , Hígado/patología , Transfusión Sanguínea , Femenino , Supervivencia de Injerto , Arteria Hepática/patología , Humanos , Lactante , Recién Nacido , Hígado/cirugía , Pruebas de Función Hepática , Masculino , Tamaño de los Órganos , Pediatría/métodos , Trombosis , Resultado del Tratamiento
10.
Biochim Biophys Acta ; 1217(3): 329-32, 1994 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-8148381

RESUMEN

Differential screening of a human fetal kidney cDNA library resulted in the isolation of D69, eventually renamed HumRPL27, which was expressed at higher levels in fetal kidney than in adult kidney. The 476 bp cDNA insert from HumRPL27 contains an open reading frame of 135 amino acids displaying 100% identity to rat RPL27 and chicken RPL27 predicted protein sequences although 64 and 38 silent base pairs changes respectively are found at the DNA level. In Northern blots, a 1.0 kb HumRPL27 mRNA transcript is expressed abundantly in all fetal tissues examined and at lower abundance in adult tissues. Southern analysis of HumRPL27 suggests the presence of multiple copies of the gene in human, rat, mouse and hamster DNA.


Asunto(s)
ADN Complementario/aislamiento & purificación , Proteínas Ribosómicas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Complementario/química , Feto/metabolismo , Humanos , Riñón/metabolismo , Datos de Secuencia Molecular , ARN Mensajero/análisis
11.
J Clin Oncol ; 18(8): 1733-9, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10764434

RESUMEN

PURPOSE: To determine whether precise definitions of response based on serial CA-125 levels can predict the activity of drugs in phase II trials for ovarian cancer as accurately as standard criteria. PATIENTS AND METHODS: Fourteen different drugs for relapsed ovarian cancer were analyzed in 25 treatment groups in 19 clinical trials. Response rates were estimated in 1,457 assessable patients according to standard criteria and in 1,092 assessable patients according to CA-125. For each drug trial, the observed response rates acted as the input data for an evaluation of how the two criteria would perform in a hypothetical Gehan two-stage phase II trial, accepting a target drug efficacy rate of 20% and a rejection error of 5%. RESULTS: CA-125 and clinical response criteria were concordant in 20 of the 25 groups, with less than 5% chance of rejecting the drug in nine groups and greater than 5% in 11 groups. In four groups, the drug had less than 5% chance of being rejected by CA-125 but greater than 5% chance of being rejected by standard criteria. The difference in the classification of drugs by the standard and CA-125 response criteria was not statistically significant (P =.38, McNemar's test). CA-125 response rates were slightly higher than standard response rates by a factor of 1.11. CONCLUSION: Definitions based on a 50% or 75% decrease of CA-125 levels accurately predicted which drugs in phase II trials for relapsed ovarian cancer were active and justified further investigation.


Asunto(s)
Antineoplásicos/uso terapéutico , Antígeno Ca-125/sangre , Neoplasias Ováricas/tratamiento farmacológico , Biomarcadores/sangre , Ensayos Clínicos Fase II como Asunto , Femenino , Humanos , Neoplasias Ováricas/sangre , Sensibilidad y Especificidad , Insuficiencia del Tratamiento
12.
J Clin Oncol ; 14(5): 1545-51, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8622070

RESUMEN

PURPOSE: To produce definitions based on serial CA 125 levels to measure response of ovarian carcinoma in patients receiving first-line chemotherapy. PATIENTS AND METHODS: Definitions were derived from analysis of 277 patients in North Thames Ovary Trial 3. Patient data were then incorporated into a computer program and tested against 254 patients in North Thames Ovary Trial 4 and 458 patients in Gynecologic Oncology Group (GOG) protocol 97. For optimum detection of response, three response definitions have been combined into a computer program. The precise definitions use mathematic logic and take account of factors such as intervening samples. Response to a specific treatment has occurred if after two samples there has been a 50% decrease, confirmed by a fourth sample (50% response), or a serial decrease over three samples of greater than 75% (75% response). The final sample has to be at least 28 days after the previous sample. RESULTS: Six hundred twenty of 989 patients were considered assessable for response according to CA 125 level. Only two patients (0.3%) had a CA 125 response at the time of clinical progression. The CA 125 response rate was 62% and 54% in the North Thames trials. In the GOG trial, it was 66% in all 317 patients assessable for CA 125 and 67% in 221 patients whose CA 125 level was not measurable according to GOG criteria, compared with a GOG-defined response rate of 62%. The sensitivity for detecting GOG-defined response was at least 68%. CONCLUSION: Definitions based on a 50% or 75% decrease of CA 125 levels have been shown reliably to define partial response of ovarian cancer in patients receiving first-line chemotherapy. These definitions should be used in addition to or instead of standard response criteria.


Asunto(s)
Antineoplásicos/uso terapéutico , Antígeno Ca-125/sangre , Carboplatino/uso terapéutico , Neoplasias Ováricas/sangre , Neoplasias Ováricas/tratamiento farmacológico , Terapia Combinada , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Evaluación de Resultado en la Atención de Salud , Neoplasias Ováricas/radioterapia
13.
Diabetes ; 47(11): 1763-70, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9792546

RESUMEN

The glucoregulatory and hormonal responses to moderate-intensity exercise (50% VO2max for 45 min) were examined in subjects with type 2 diabetes and mild hyperglycemia. We studied seven obese subjects with type 2 diabetes and seven lean and seven obese control subjects (fasting plasma glucose levels, 7.5 +/- 0.5, 4.8 +/- 0.1, and 5.2 +/- 0.1 mmol/l, respectively). Glucose production, utilization, and cycling (flux between glucose and glucose-6-phosphate [G-6-P]) were measured with [6-(3)H]glucose and [2-(3)H]glucose using the constant specific-activity method. Insulin levels decreased normally during exercise in diabetic subjects. Plasma glucose levels decreased in diabetic subjects, but remained constant in control subjects. Basal glucose production was not different among groups and increased similarly during exercise. The decrease in plasma glucose in diabetic subjects was due to greater glucose utilization (867 +/- 83 vs. 726 +/- 143 micromol x m(-2) x min(-1); P < 0.05). This was a consequence of the mass effect of hyperglycemia, since glucose metabolic clearance increased similarly in all groups. Glucose cycling, expressed as a percentage of total glucose output (i.e., flux through G-6-P) was elevated at rest (P < 0.01), but decreased during exercise (P < 0.01). The catecholamine response to exercise was blunted in diabetic subjects, presumably indicating autonomic dysfunction. In conclusion, during moderate-intensity exercise in obese diabetic subjects with mild hyperglycemia, 1) insulin secretory responses were normally regulated; 2) glucose homeostasis was different from that in nondiabetic subjects because glucose levels decreased during exercise; 3) the decrease in plasma glucose was due to greater-than-normal rates of glucose utilization, which were sustained by hyperglycemia; and 4) elevated basal rates of glucose cycling decreased during exercise, presumably because exercise simultaneously lowered plasma glucose, was associated with a blunted catecholamine response, and accentuated an underlying defect in hepatic glucokinase activity in type 2 diabetes.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus/sangre , Ejercicio Físico/fisiología , Glucosa/biosíntesis , Hiperglucemia/sangre , Obesidad , Adulto , Alanina/sangre , Péptido C/sangre , Femenino , Glucosa-6-Fosfato/sangre , Homeostasis , Humanos , Insulina/sangre , Ácido Láctico/sangre , Masculino , Oxidación-Reducción , Consumo de Oxígeno , Tritio
14.
Lancet ; 363(9418): 1354-7, 2004 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-15110492

RESUMEN

BACKGROUND: Before 1999, infants born in the UK with suspected biliary atresia were investigated in regional centres, and, if confirmed, a Kasai operation was done there. Since 1999, all infants with suspected biliary atresia in England and Wales, UK, have been referred to one of three designated centres where both the Kasai operation and liver transplantation (if necessary) could be done. METHODS: We assessed clearance of jaundice (bilirubin <20 micromol/L) as an early outcome in all cases of biliary atresia referred from one of the three centres. We then estimated survival using the Kaplan-Meier method with endpoints of liver transplantation or death. FINDINGS: 148 infants with biliary atresia were treated between January, 1999, and June, 2002. A primary portoenterostomy was done in 142 (96%) infants and a primary liver transplant in five (3%). One child died before any intervention. Early clearance of jaundice after portoenterostomy was achieved in 81 of 142 (57%) infants. Liver transplantation was done in 52 (37%) of those undergoing portoenterostomy. 13 (9%) infants died. Of the 135 children who survived, 84 (62%) still have their native liver and 51 (38%) had transplantation. The median follow-up of survivors was 2.13 (range 0.5-4.1) years. The overall 4-year estimated actuarial survival was 89% (95% CI 82-94). The 4-year estimated actuarial survival with native liver was 51% (42-59%). INTERPRETATION: Our early results suggest that surgical outcome can be improved by centralisation of care to supra-regional centres.


Asunto(s)
Atresia Biliar/cirugía , Atresia Biliar/complicaciones , Atresia Biliar/mortalidad , Inglaterra/epidemiología , Estudios de Seguimiento , Instituciones de Salud , Humanos , Lactante , Recién Nacido , Trasplante de Hígado , Portoenterostomía Hepática/efectos adversos , Derivación y Consulta , Bazo/anomalías , Tasa de Supervivencia , Gales/epidemiología
15.
Genetics ; 112(3): 649-67, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17246320

RESUMEN

Sequence divergence among the mitochondrial (mt) DNA of nine Lycopersicon and two closely related Solanum species was estimated using the shared fragment method. A portion of each mt genome was highlighted by probing total DNA with a series of plasmid clones containing mt-specific DNA fragments from Lycopersicon pennellii. A total of 660 fragments were compared. As calculated by the shared fragment method, sequence divergence among the mtDNAs ranged from 0.4% for the L. esculentum-L. esculentum var. cerasiforme pair to 2.7% for the Solanum rickii-L. pimpinellifolium and L. cheesmanii-L. chilense pairs. The mtDNA divergence is higher than that reported for Lycopersicon chloroplast (cp) DNA, which indicates that the DNAs of the two plant organelles are evolving at different rates. The percentages of shared fragments were used to construct a phenogram that illustrates the present-day relationships of the mtDNAs. The mtDNA-derived phenogram places L. hirsutum closer to L. esculentum than taxonomic and cpDNA comparisons. Further, the recent assignment of L. pennellii to the genus Lycopersicon is supported by the mtDNA analysis.

16.
Mol Plant Microbe Interact ; 13(11): 1237-42, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11059490

RESUMEN

Race-specific resistance to the bean rust pathogen (Uromyces appendiculatus) is provided by a number of loci in common bean (Phaseolus vulgaris). The Ur-3 locus controls hypersensitive resistance (HR) to 44 of the 89 races curated in the United States. To better understand resistance mediated by this locus, we developed new genetic material for analysis. We developed a population of mutagenized seed of cv. Sierra (genotype = Ur-3 ur-4 ur-6) that was screened with a bean rust race that is normally incompatible (HR response) on Ur-3 genotypes. We discovered two mutants of common bean, crg and ur3-delta3, in which uredinia formed on leaves (a compatible interaction) following infection. The F1 generation from a cross of these two mutants expressed the HR response, and the F2 generation segregated in a ratio of 9:7 (HR/uredinia formation). Therefore, the two genes are unlinked. Further genetic analysis determined that the mutation in ur3-delta3 was in the Ur-3 locus, and the mutation in crg was in a newly discovered gene given the symbol Crg (Complements resistance gene). Each mutation was inherited in a recessive manner. Unlike ur3-delta3, crg expressed reduced compatibility to bean rust races 49 and 47 that are normally fully compatible on genotypes, such as Sierra, that are homozygous recessive at the Ur-4 and Ur-6 loci. This suggests a gene mutated in crg is normally a positive compatibility factor for the bean-bean rust interaction. Polymerase chain reaction analysis of crg with primers to common bean resistance gene analogs (RGA) that contain a nucleotide-binding site sequence similar to those found in a number of plant disease resistance genes revealed that crg is missing the SB1 RGA, but not the linked SB3 and SB5 RGAs. Genetic analyses revealed that Crg cosegregates with the SB1 RGA. These results demonstrate that Crg is located near a RGA cluster in the common bean genome.


Asunto(s)
Basidiomycota/genética , Fabaceae/microbiología , Genes Fúngicos , Enfermedades de las Plantas/microbiología , Plantas Medicinales , Mapeo Cromosómico , Prueba de Complementación Genética , Mutación , Especificidad de la Especie
17.
J Clin Endocrinol Metab ; 44(4): 708-20, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-849981

RESUMEN

The responses to moderate exercise of circulating energy fuels and endocrine pancreatic hormones were examined in insulin-dependent diabetics receiving insulin either sc or by continuous iv infusion. Eight subjects received one-third of their usual daily insulin doses sc in the thigh 1 h prior to exercise. Seven subjects exercised during infusion (iv) of insulin at 8-20 mU"min, started 12-14 h earlier. Exercise was on a bicycle ergometer for 45 min at 50% maximum oxygen consumption. The diabetics receiving sc insulin showed a sharp decline in glycemia from elevated resting levels (227 +/- 16 mg/dl), in contrast to the control subjects whose glycemia did not change. The control subjects insulin (IRI) fell, and glucagon (IRG) remained unchanged. In the sc-insulin diabetics, exercise induced a further rise in IRG from elevated levels (296 +/- 76 pg/ml). Resting lactate, pyruvate and alanine were normal and increased as in controls. Though FFA, glycerol and ketone body levels were normal at rest, FFA failed to rise with exercise as in the controls and glycerol and ketone body increments were smaller. RQ increased and remained elevated in contrast to the later fall in controls during exercise. These results are consistent with selective insulin deficiency at rest, and increased insulin effect during exercise. This resulted in greater carbohydrate utilization during exercise, but without the normal shift back toward utilization of fat-derived fuels with continuation of exercise. Diabetics receiving insulin by infusion showed no glycemic change with exercise. Exercise caused greater increases in lactate and pyruvate levels (4-fold), although alanine levels increased only during recovery. The significantly elevated resting FFA levels showed a rise which was sustained at higher than control values during recovery; glycerol and ketone body increments also tended to be greater than in controls. Intravenous insulin sustained euglycemia in exercise, obviating the fall in glycemia with sc insulin. The responses of other metabolite levels were abnormal, and consistent with a subtle degree of underinsulinization.


Asunto(s)
Diabetes Mellitus/metabolismo , Insulina/uso terapéutico , Esfuerzo Físico , Adulto , Alanina/sangre , Antígenos , Ácidos Grasos no Esterificados/sangre , Femenino , Glucagón/sangre , Glicerol/sangre , Frecuencia Cardíaca , Humanos , Hidroxibutiratos/sangre , Inyecciones Intravenosas , Inyecciones Subcutáneas , Insulina/administración & dosificación , Insulina/sangre , Lactatos/sangre , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Piruvatos/sangre
18.
Gene ; 124(1): 127-30, 1993 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-8440474

RESUMEN

A 747-bp tandem repeat element from the genome of the fungus Plasmopara halstedii, the causal agent of downy mildew of sunflower, was cloned and analyzed. The clone can be used as a probe to distinguish races of the pathogen. Sequence analysis of a copy of this element revealed the presence of 103 direct repeats of 6 bp or greater and two potential ORFs. This tandemly repeated element consists of four subunits that may have evolved as a result of several unequal crossing-over events.


Asunto(s)
Hongos/genética , Genoma Fúngico , Secuencias Repetitivas de Ácidos Nucleicos , Secuencia de Bases , Clonación Molecular , ADN de Hongos/genética , Biblioteca Genómica , Datos de Secuencia Molecular , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico
19.
Gene ; 186(2): 293-7, 1997 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-9074509

RESUMEN

The organization of the gene encoding potato UDP-glucose pyrophosphorylase, one of the key enzymes of carbohydrate metabolic pathway is presented. The gene cloned from cultivar (cv.) Lemhi consists of a 6.6-kb structural and a 1-kb regulatory region. The structural region contains 20 exons and 19 introns. The coding sequence with exception of three bases is identical with the UGPase cDNA previously cloned from Danshaku-Imo cv. [Katsube et al. (1990) UDP-Glucose pyrophosphorylase from potato tuber: cDNA cloning and sequencing. J. Biochem. 108, 321-326]. The largest intron contains a tandem repeat consisting of 50 nt core units. A putative polyadenylation site is situated 79 bp downstream of the translation stop codon. A transcription start point (tsp) and a putative TATA-box were located 84 bp and 141 bp upstream of the translation start, respectively. The regulatory region contained general enhancer, suppressor, and regions responsible for tissue specificity of UGPase expression.


Asunto(s)
Solanum tuberosum/enzimología , Solanum tuberosum/genética , Transcripción Genética , UTP-Glucosa-1-Fosfato Uridililtransferasa/biosíntesis , UTP-Glucosa-1-Fosfato Uridililtransferasa/genética , Secuencia de Bases , Clonación Molecular , Exones , Intrones , Datos de Secuencia Molecular , Biosíntesis de Proteínas , Proteínas Recombinantes/biosíntesis , Secuencias Reguladoras de Ácidos Nucleicos , Mapeo Restrictivo
20.
Aliment Pharmacol Ther ; 4(5): 457-64, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2129634

RESUMEN

Sixty infants were randomly assigned to one of three groups on admission to hospital with a diagnosis of gastroenteritis. After rehydration, Group A received a low-lactose, low-fat feed (HN25) in full strength; Group B were regarded on to a conventional formula (SMA); Group C received a hydrolysed soya and collagen feed (Prejomin) in full strength. All feeds were continued for 5 days. The median duration of loose stools from starting the feed was 24 hours in Group A, compared to 119 hours and 95 hours in Groups B and C, respectively. Group A showed a mean percentage increase in weight of 2.34%, Group B showed a mean loss of 1.45%, and Group C a mean increase of 0.15%. These differences were statistically significant. Recovery from gastroenteritis is hastened by the use of a low-lactose, low-fat feed in the initial post-rehydration phase of the disease.


Asunto(s)
Gastroenteritis/terapia , Enfermedad Aguda , Peso Corporal , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Femenino , Fluidoterapia , Humanos , Lactante , Alimentos Infantiles , Recién Nacido , Masculino , Fenómenos Fisiológicos de la Nutrición
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