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1.
Toxicol Res (Camb) ; 7(1): 102-116, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30090567

RESUMEN

Silver nanoparticles (AgNPs) are widely used in industrial and medical applications and humans may be exposed through different routes, increasing the risk of toxicity. We investigated the transcript expression of genes involved in the regulation of the hypothalamic-pituitary-testicular (HPT) axis and the parameters associated with sperm functionality after prepubertal exposure. AgNPs modulated the transcript expression of genes involved in the control of the HPT axis and spermatogenesis in the groups treated with lower doses, while the functional parameters related to sperm and puberty were affected in the groups administered higher doses. These results suggest that the HPT axis is disrupted by AgNPs during the prepubertal and pubertal periods, which are highly susceptible windows for the endocrine-disrupting chemical activity.

2.
Perfusion ; 27(2): 141-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22143092

RESUMEN

Lower extremity ischemia is common when the femoral artery is used for veno-arterial extracorporeal membrane oxygenation (VA ECMO). We describe a new technique to reperfuse the extremity. The ipsilateral posterior tibial artery is exposed via a small incision behind the medial malleolus. The vessel is cannulated in a retrograde fashion and connected to the arterial limb of the ECMO circuit. Thirty-six patients received a posterior tibial reperfusion cannula: average flow was 155.8 ml/min and increased over the initial 24 hours. Fifty-eight percent received the posterior tibial cannula within 6 hours of ECMO initiation and none sustained permanent lower extremity injury. Of the remaining 42%, three required amputation or developed permanent neurologic injury. Overall survival was 41%. Cannulation of the posterior tibial artery is a simple technique to reperfuse the lower extremity during VA ECMO. The cannula should be inserted within 6 hours of ECMO initiation to avoid irreversible ischemic damage.


Asunto(s)
Oxigenación por Membrana Extracorpórea/métodos , Arteria Femoral/cirugía , Isquemia/prevención & control , Pierna/irrigación sanguínea , Tibia/irrigación sanguínea , Arterias Tibiales/cirugía , Adolescente , Adulto , Cateterismo/métodos , Niño , Estudios de Cohortes , Oxigenación por Membrana Extracorpórea/efectos adversos , Humanos , Isquemia/etiología , Pierna/cirugía , Persona de Mediana Edad , Tibia/cirugía , Adulto Joven
3.
Arch Toxicol ; 84(4): 309-17, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20012598

RESUMEN

Glyphosate is a herbicide widely used to kill weeds both in agricultural and non-agricultural landscapes. Its reproductive toxicity is related to the inhibition of a StAR protein and an aromatase enzyme, which causes an in vitro reduction in testosterone and estradiol synthesis. Studies in vivo about this herbicide effects in prepubertal Wistar rats reproductive development were not performed at this moment. Evaluations included the progression of puberty, body development, the hormonal production of testosterone, estradiol and corticosterone, and the morphology of the testis. Results showed that the herbicide (1) significantly changed the progression of puberty in a dose-dependent manner; (2) reduced the testosterone production, in semineferous tubules' morphology, decreased significantly the epithelium height (P < 0.001; control = 85.8 +/- 2.8 microm; 5 mg/kg = 71.9 +/- 5.3 microm; 50 mg/kg = 69.1 +/- 1.7 microm; 250 mg/kg = 65.2 +/- 1.3 microm) and increased the luminal diameter (P < 0.01; control = 94.0 +/- 5.7 microm; 5 mg/kg = 116.6 +/- 6.6 microm; 50 mg/kg = 114.3 +/- 3.1 microm; 250 mg/kg = 130.3 +/- 4.8 microm); (4) no difference in tubular diameter was observed; and (5) relative to the controls, no differences in serum corticosterone or estradiol levels were detected, but the concentrations of testosterone serum were lower in all treated groups (P < 0.001; control = 154.5 +/- 12.9 ng/dL; 5 mg/kg = 108.6 +/- 19.6 ng/dL; 50 mg/dL = 84.5 +/- 12.2 ng/dL; 250 mg/kg = 76.9 +/- 14.2 ng/dL). These results suggest that commercial formulation of glyphosate is a potent endocrine disruptor in vivo, causing disturbances in the reproductive development of rats when the exposure was performed during the puberty period.


Asunto(s)
Glicina/análogos & derivados , Herbicidas/toxicidad , Testículo/efectos de los fármacos , Testosterona/sangre , Glándulas Suprarrenales/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Corticosterona/sangre , Exposición a Riesgos Ambientales , Estradiol/sangre , Glicina/toxicidad , Crecimiento y Desarrollo/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Wistar , Testículo/anatomía & histología , Testículo/metabolismo , Glifosato
4.
Mem Inst Oswaldo Cruz ; 104(2): 374-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19430667

RESUMEN

By 1997, an open cohort of 1,652 live newborn of 1,637 mothers with gestational toxoplasmosis had been recruited in the Campania region to monitor the burden of congenital toxoplasmosis (CT). Of the 1,556 mother-child pairs that completed the follow up, 92 definite cases were detected, yielding a 5.9% (4.8-7.1 95% CI) transmission rate. The onset was patent for 43% of patients and sensorineural complications were shown for a further 15% of subclinical onset patients later than two years of age. The overall prevalence of toxoplasmosis during gestation was 2.46 of 1,000 deliveries, while the prevalence of definite CT was 1.38 of 10,000 live newborns. However, there is still room for intervention, as only 23% of the maternal diagnoses were proven through seroconversion, 63 of the late-gestation seroconverters remained untreated, and six probable CT diagnoses were made following referrals due to patent sequelae and born during the study period. There was a positive secular trend on the rates of infant referral and definite CT diagnosis, according to the live birth rate (Chi2 for trend < 0.001). Extension of this surveillance system across the country could help to define a future strategy for prevention.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Tamizaje Neonatal/métodos , Evaluación de Procesos y Resultados en Atención de Salud , Complicaciones Parasitarias del Embarazo/diagnóstico , Toxoplasmosis Congénita/diagnóstico , Animales , Antiprotozoarios/administración & dosificación , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Italia/epidemiología , Embarazo , Complicaciones Parasitarias del Embarazo/tratamiento farmacológico , Complicaciones Parasitarias del Embarazo/epidemiología , Diagnóstico Prenatal , Prevalencia , Toxoplasmosis Congénita/epidemiología , Toxoplasmosis Congénita/prevención & control
5.
Reprod Domest Anim ; 42(6): 616-22, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17976069

RESUMEN

The objective of this study was to characterize follicular dynamics in pre-pubertal, pubertal and post-pubertal periods, as well as the effect of high-energy intake on follicular development and age at puberty in heifers. Thirty-one Nelore (Bos indicus) heifers, 6 months old, were randomly assigned to receive two different diets: one of low (GI) and other of high dietary energy intake (GII). Animals were evaluated in relation to body weight gain by being weighed every 21 days. Heifers were evaluated every other day by real-time linear ultrasonography to characterize ovarian structures development from weaning to post-pubertal period. Blood samples were collected to determine plasmatic concentrations of progesterone by RIA method. The ovulation was determined when progesterone concentrations were >1 ng/mL in three consecutive samples, and by ultrasound images of corpus luteum; and oestrous behaviour in some animals. Age at puberty differed among heifers of GII (17.00 +/- 0.46 months) compared with heifers of GI (19.87 +/- 0.47 months; p < or = 0.05). Maximum size of the dominant follicles at pre-pubertal period was greater in GII heifers than in GI (10.52 +/- 0.33 and 9.76 +/- 0.15 mm, respectively; p < or = 0.05). As heifers approached first ovulation time, size of dominant follicle increased (11.75 +/- 0.37 mm for GI and 12.52 +/- 0.91 mm for GII; p < or = 0.05). Body weight at puberty was not different in both groups (302.33 +/- 27.31 kg for GI and 326.19 +/- 27.78 kg for GII heifers; p > 0.05). We conclude that animals receiving high dietary energy intake attained the puberty earlier and the development of follicles were different than in low dietary energy intake.


Asunto(s)
Envejecimiento/fisiología , Bovinos/fisiología , Ingestión de Energía/fisiología , Folículo Ovárico/fisiología , Maduración Sexual/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos/sangre , Bovinos/crecimiento & desarrollo , Dieta , Ingestión de Alimentos , Femenino , Folículo Ovárico/anatomía & histología , Progesterona/sangre , Aumento de Peso/fisiología
7.
J Immunol ; 165(12): 7017-24, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11120829

RESUMEN

Epigenetic mechanisms are involved in regulating chromatin structure and gene expression through repression. In this study, we show that histone deacetylase inhibitors (DAIs) that alter the acetylation of histones in chromatin enhance the expression of several genes on tumor cells including: MHC class I, II, and the costimulatory molecule CD40. Enhanced transcription results in a significant increase in protein expression on the tumor cell surface, and expression can be elicited on some tumors that are unresponsive to IFN-gamma. The magnitude of induction of these genes cannot be explained by the effect of DAIs on the cell cycle or enhanced apoptosis. Induction of class II genes by DAIs was accompanied by activation of a repressed class II transactivator gene in a plasma cell tumor but, in several other tumor cell lines, class II was induced in the apparent absence of class II transactivator transcripts. These findings also suggest that the abnormalities observed in some tumors in the expression of genes critical to tumor immunity may result from epigenetic alterations in chromatin and gene regulation in addition to well-established mutational mechanisms.


Asunto(s)
Antígenos CD40/biosíntesis , Antígenos CD40/genética , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/inmunología , Genes MHC Clase II/efectos de los fármacos , Genes MHC Clase I/efectos de los fármacos , Inhibidores de Histona Desacetilasas , Proteínas Nucleares , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Apoptosis/inmunología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Ciclo Celular/inmunología , Cromatina/enzimología , Cromatina/genética , Regulación de la Expresión Génica/efectos de los fármacos , Antígenos de Histocompatibilidad Clase II/biosíntesis , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Ácidos Hidroxámicos/farmacología , Interferón gamma/farmacología , Ratones , ARN Mensajero/biosíntesis , Transactivadores/biosíntesis , Transactivadores/genética , Células Tumorales Cultivadas
8.
Neuroscience ; 93(3): 1189-96, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10473284

RESUMEN

In this study, we investigated the cellular distribution of iron in the brain of Belgrade rats. These rats have a mutation in Divalent Metal Transporter 1, which has been implicated in iron transport from endosomes. The Belgrade rats have iron-positive pyramidal neurons, but these are fewer in number and less intensely stained than in controls. In the white matter, iron is normally present in patches of intensely iron-stained oligodendrocytes and myelin, but there is dramatically less iron staining in the Belgrade rat. Those oligodendrocytes that stained for iron did so strongly and were associated with blood vessels. Astrocytic iron staining was seen in the cerebral cortex for both normal rats and Belgrade rats, but the iron-stained astrocytes were less numerous in the mutants. Iron staining in tanycytes, modified astrocytes coursing from the third ventricle to the hypothalamus, was not affected in the Belgrade rat, but was affected by diet. The results of this study indicate that Divalent Metal Transporter 1 is important to iron transport in the brain. Iron is essential in the brain for basic metabolic processes such as heme formation, neurotransmitter production and ATP synthesis. Excess brain iron is associated with a number of common neurodegenerative diseases. Consequently, elucidating the mechanisms of brain iron delivery is critical for understanding the role of iron in pathological conditions.


Asunto(s)
Anemia Hipocrómica/metabolismo , Química Encefálica , Proteínas Portadoras/metabolismo , Proteínas de Transporte de Catión , Proteínas de Unión a Hierro , Hierro/análisis , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/deficiencia , Ratas Mutantes/metabolismo , Sustitución de Aminoácidos , Anemia Hipocrómica/genética , Animales , Astrocitos/química , Proteínas Portadoras/genética , Cruzamientos Genéticos , Dieta , Endosomas/metabolismo , Femenino , Masculino , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Oligodendroglía/química , Oligodendroglía/patología , Especificidad de Órganos , Mutación Puntual , Ratas , Ratas Endogámicas F344 , Ratas Wistar
9.
Biochim Biophys Acta ; 1449(2): 125-36, 1999 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-10082971

RESUMEN

The Belgrade rat has a microcytic, hypochromic anemia inherited as an autosomal recessive trait (gene symbol b). Transferrin-dependent iron uptake is defective because of a mutation in Nramp2 (now DMT1, also called DCT1), the protein responsible for endosomal iron efflux. Hence, Belgrade reticulocytes are iron deficient. We show that a chromatographic method is able to measure the amount of 'free' heme in reticulocytes. Most of the 'free' heme is the result of biosynthesis. Succinylacetone, an inhibitor of heme synthesis, decreases the level of 'free' heme and cycloheximide, an inhibitor of globin synthesis, increases the 'free' heme level. In a pulse-chase experiment with 59Fe-transferrin, the 'free' heme pool behaves as an intermediate, with a half-life of just over 2 h. Belgrade reticulocytes contain about 40% as much 'free' heme as do heterozygous or homozygous reticulocytes. This deficiency of 'free' heme slows initiation of translation in Belgrade reticulocytes by increasing the level of an inhibitor of initiation. Thus the Belgrade rat makes a whole animal model available with chronic heme deficiency.


Asunto(s)
Anemia Hipocrómica/genética , Hemo/deficiencia , Reticulocitos/metabolismo , Anemia Hipocrómica/sangre , Animales , Sistema Libre de Células , Cicloheximida/farmacología , Modelos Animales de Enfermedad , Hemo/biosíntesis , Heptanoatos/farmacología , Hierro/metabolismo , Ratas , Reticulocitos/efectos de los fármacos
10.
Genomics ; 55(2): 194-201, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9933566

RESUMEN

Genomic imprinting is an epigenetic modification that can lead to parental-specific monoallelic expression of specific autosomal genes. While methylation of CpG dinucleotides is thought to be a strong candidate for this epigenetic modification, little is known about the establishment or maintenance of parental origin-specific methylation patterns. We have recently identified a portion of mouse chromosome 9 containing a paternally methylated region associated with a paternally expressed imprinted gene, Ras protein-specific guanine nucleotide-releasing factor 1 (Rasgrf1). This area of chromosome 9 also contains a short, direct tandem repeat in close proximity to a paternally methylated NotI site 30 kb upstream of Rasgrf1. Short, direct tandem repeats have been found associated with other imprinted genes and may act as important regulatory structures. Here we demonstrate that two rodent species (Mus and Rattus) contain a similar direct repeat structure associated with a region of paternal-specific methylation. In both species, the Rasgrf1 gene shows paternal-specific monoallelic expression in neonatal brain. A more divergent rodent species (Peromyscus) appears to lack a similar repeat structure based on Southern Blot analysis. Peromyscus animals show biallelic expression of Rasgrf1 in neonatal brain. These results suggest that direct repeat elements may play an important role in the imprinting process.


Asunto(s)
Impresión Genómica , Proteínas/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Animales , Secuencia de Bases , Southern Blotting , Encéfalo/embriología , Encéfalo/metabolismo , Mapeo Cromosómico , Regulación del Desarrollo de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido , Pulmón/embriología , Pulmón/metabolismo , Ratones , Datos de Secuencia Molecular , Muridae , Peromyscus , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad de la Especie , Factores de Intercambio de Guanina Nucleótido ras , Proteínas ras
11.
J Cell Physiol ; 178(3): 349-58, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9989781

RESUMEN

Belgrade (b) rats have an autosomal recessive, microcytic, hypochromic anemia. Transferrin (Tf)-dependent iron uptake is defective because of a mutation in DMT1 (Nramp2), blocking endosomal iron efflux. This experiment of nature permits the present study to address whether the mutation also affects non-Tf-bound iron (NTBI) uptake and to use NTBI uptake compared to Tf-Fe utilization to increase understanding of the phenotype of the b mutation. The distribution of 59Fe2+ into intact erythroid cells and cytosolic, stromal, heme, and nonheme fractions was different after NTBI uptake vs. Tf-Fe uptake, with the former exhibiting less iron into heme but more into stromal and nonheme fractions. Both reticulocytes and erythrocytes exhibit NTBI uptake. Only reticulocytes had heme incorporation after NTBI uptake. Properly normalized, incorporation into b/b heme was approximately 20% of +/b, a decrease similar to that for Tf-Fe utilization. NTBI uptake into heme was inhibited by bafilomycin A1, concanamycin, NH4Cl, or chloroquine, consistent with the endosomal location of the transporter; cellular uptake was uninhibited. NTBI uptake was unaffected after removal of Tf receptors by Pronase or depletion of endogenous Tf. Concentration dependence revealed that NTBI uptake into cells, cytosol, stroma, and the nonheme fraction had an apparent low affinity for iron; heme incorporation behaved like a high-affinity process, as did an expression assay for DMT1. DMT1 serves in both apparent high-affinity NTBI membrane transport and the exit of iron from the endosome during Tf delivery of iron in rat reticulocytes; the low-affinity membrane transporter, however, exhibits little dependence on DMT1.


Asunto(s)
Anemia Hipocrómica/sangre , Proteínas Portadoras/metabolismo , Proteínas de Transporte de Catión , Proteínas de Unión a Hierro , Hierro/sangre , Proteínas de la Membrana/metabolismo , Reticulocitos/metabolismo , Transferrina/metabolismo , Anemia Hipocrómica/genética , Animales , Transporte Biológico , Línea Celular , Endosomas/metabolismo , Heterocigoto , Humanos , Técnicas In Vitro , Hierro/metabolismo , Cinética , Mutación Puntual , Ratas , Ratas Mutantes , Proteínas Recombinantes/metabolismo , Valores de Referencia , Transfección , Transferrina/genética
12.
J Helminthol ; 72(4): 325-30, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9858629

RESUMEN

Miracidia of Echinostoma caproni were exposed to solutions varying in salinity, pH, and temperature in 1 ml concavity slides. Half-lives of the miracidial populations were determined and longevity curves constructed to find maximum life spans of the miracidia in the different conditions. Control miracidia in aquarium water at pH 7.2 and 22 degrees C. had a half-life of 3.6 h and a maximum life span of 9 h. Miracidia of E. caproni were not very tolerant of saline solutions from 0.1% to 0.4%, the latter being lethal within an hour. A bimodal effect was found with exposure to aquarium water of varying pH, with a peak at pH 5 in acid solutions and pH 9 in alkaline solutions. Miracidia tolerated pH ranges from 3 to 11 exhibiting half-lives of 2.4 h or greater in these solutions. At lower than ambient temperatures, E. caproni miracidia lived longer, the greatest being a half-life of 5.0 h and a maximum life span of 15 h at 5 degrees C. At warmer temperatures, the half-life was reduced until lethality was reached at 40 degrees C. ANCOVA analysis of log transformed longevity curves supported the observation that in pH trials many miracidia survived initially with a major die-off after 3.3 h. The opposite trend of early die-off and gradual mortality of the survivors was supported in the temperature trials.


Asunto(s)
Echinostoma/efectos de los fármacos , Cloruro de Sodio/farmacología , Animales , Relación Dosis-Respuesta a Droga , Semivida , Concentración de Iones de Hidrógeno , Longevidad , Ratones , Tasa de Supervivencia , Temperatura
13.
Arch Environ Contam Toxicol ; 35(2): 302-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9680522

RESUMEN

For nearly 50 years, the fingernail clam (Musculium transversum) was believed to be virtually eliminated from the Illinois River. In 1991, workers began finding substantial populations of M. transversum in the Illinois River including several beds in and around the highly polluted Chicago Sanitary District. In order to determine if populations of M. transversum from polluted sites exhibited any genetic response to the high levels of toxins and to examine the genetic structure of several populations of M. transversum for any changes due to the population crash, starch-gel electrophoresis was performed on M. transversum from three Illinois River localities and four Mississippi River basin locations. The sampled populations produced an inbreeding coefficient (FIS) of 0.929, indicating that the populations were highly inbred. The results of a suspected founder effect due to a bottleneck was suggested by an FST = 0.442. The isozyme Glucose-6-phosphate isomerase-2 (Gpi-2) produced allelic frequency patterns that were consistent with expected patterns of a pollution-tolerant allele. Polluted sites exhibited elevated frequencies of Gpi-2(100) whereas nonpolluted sites exhibited elevated frequencies of Gpi-2(74). This frequency pattern suggested that natural selection was occurring in populations under severe toxic pressures, leading to an increase in the frequency of the allele Gpi-2(100). Therefore, Gpi-2(100) is a possible pollution-tolerant mutation in M. transversum.


Asunto(s)
Bivalvos/genética , Frecuencia de los Genes , Glucosa-6-Fosfato Isomerasa/genética , Contaminantes Químicos del Agua , Animales , Illinois , Densidad de Población , Selección Genética
14.
J Thorac Cardiovasc Surg ; 115(6): 1273-7; discussion 1277-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9628668

RESUMEN

BACKGROUND: There has been resurgent interest in coronary revascularization performed on the beating heart. Heretofore, there has been no long-term comparison of this technique to traditional coronary artery bypass with cardioplegia. OBJECTIVE: The purpose of this study was to provide a comparison of long-term survival and intervention-free outcome between patient groups subjected to coronary bypass accomplished with or without the use of cardiopulmonary bypass. METHOD: From June 1989 to July 1990, all patients treated for coronary revascularization by three surgeons were considered for coronary revascularization with the heart beating: 107 patients underwent coronary bypass on the beating heart, and 112 patients underwent revascularization with the aid of bypass with cardioplegia. Mean ages (65 +/- 10 years) and risk factors were identical. Patients operated on with the heart beating had 2.4 +/- 0.9 grafts versus 3.2 +/- 1.1 grafts for patients having cardiopulmonary bypass with cardioplegia. RESULTS: At 7-year follow-up, 86 of 107 (80%) patients operated on with the heart beating were alive versus 88 of 112 (79%) patients in whom cardiopulmonary bypass with cardioplegia was used. Cardiac deaths occurred in 13 of 107 (12%) patients in the former group versus 10 of 112 (9%) patients in the latter group. However, 32 of 107 patients operated on with the heart beating (30%) needed catheterization for their symptoms versus 18 of 112 (16%) patients in the bypass with cardioplegia group (p = 0.01). This results in 21 of 107 (20%) patients in the beating heart group needing angioplasty or a second coronary bypass versus only 8 of 112 (7%) patients in the bypass with cardioplegia group. No patient in the bypass with cardioplegia group required reoperation. Most of the reinterventions for the beating heart group were percutaneous transluminal coronary angioplasty (15 of 21 [71%] patients). CONCLUSION: Despite one less graft per patient, survival and cardiac death rates were similar for the two groups. However, twice as many patients in the beating heart group required recatheterization (30% versus 16%), and 20% needed a second intervention. Only 7% of the bypass with cardioplegia group required reintervention. Limited revascularization of the beating heart provides long-term results comparable to full revascularization with cardiopulmonary bypass, but at the cost of a threefold increase in reinterventions.


Asunto(s)
Puente Cardiopulmonar , Puente de Arteria Coronaria/métodos , Enfermedad Coronaria/cirugía , Anciano , Angioplastia Coronaria con Balón , Cateterismo Cardíaco , Puente Cardiopulmonar/mortalidad , Puente de Arteria Coronaria/mortalidad , Enfermedad Coronaria/mortalidad , Muerte , Estudios de Factibilidad , Estudios de Seguimiento , Humanos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/cirugía , Reoperación , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
15.
Proc Natl Acad Sci U S A ; 95(3): 1148-53, 1998 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-9448300

RESUMEN

The Belgrade (b) rat has an autosomal recessively inherited, microcytic, hypochromic anemia associated with abnormal reticulocyte iron uptake and gastrointestinal iron absorption. The b reticulocyte defect appears to be failure of iron transport out of endosomes within the transferrin cycle. Aspects of this phenotype are similar to those reported for the microcytic anemia (mk) mutation in the mouse. Recently, mk has been attributed to a missense mutation in the gene encoding the putative iron transporter protein Nramp2. To investigate the possibility that Nramp2 was also mutated in the b rat, we established linkage of the phenotype to the centromeric portion of rat chromosome 7. This region exhibits synteny to the chromosomal location of Nramp2 in the mouse. A polymorphism within the rat Nramp2 gene cosegregated with the b phenotype. A glycine-to-arginine missense mutation (G185R) was present in the b Nramp2 gene, but not in the normal allele. Strikingly, this amino acid alteration is the same as that seen in the mk mouse. Functional studies of the protein encoded by the b allele of rat Nramp2 demonstrated that the mutation disrupted iron transport. These results confirm the hypothesis that Nramp2 is the protein defective in the Belgrade rat and raise the possibility that the phenotype shared by mk and b animals is unique to the G185R mutation. Furthermore, the phenotypic characteristics of these animals indicate that Nramp2 is essential both for normal intestinal iron absorption and for transport of iron out of the transferrin cycle endosome.


Asunto(s)
Anemia Hipocrómica/genética , Proteínas Portadoras/genética , Proteínas Portadoras/fisiología , Proteínas de Transporte de Catión , Endosomas/metabolismo , Proteínas de Unión a Hierro , Hierro/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Mutación , Alelos , Secuencia de Aminoácidos , Anemia Hipocrómica/metabolismo , Animales , Arginina/genética , Arginina/metabolismo , Transporte Biológico , Mapeo Cromosómico , Codón , Ligamiento Genético , Genotipo , Glicina/genética , Glicina/metabolismo , Ratones , Datos de Secuencia Molecular , Ratas , Alineación de Secuencia , Transferrina/metabolismo
16.
Braz. j. vet. res. anim. sci ; 35(1): 25-8, 1998. tab
Artículo en Portugués | LILACS | ID: lil-265992

RESUMEN

No presente estudo, foram utilizadas 21 éguas, das quais em 11 Puros-Sangues Arabes (PSA) e 10 Cruza Arabes (CA), entre 3 e 11 anos de idade. Para identificaçäo do estro (cio) utilizaram-se os métodos de rufiaçäo e palpaçäo retal, sendo que as éguas foram rufiadas 3 vezes ao dia até o final do estro para determinaçäo de sua duraçäo. Independente do estágio do ciclo, todos os animais foram examinados pelo menos 3 vezes por semana. Nos diagnóstico do momento de ovulaçäo, as éguas foram examinadas às 8 h, 12 h e 16 h durante todo o período de estro, verificando-se as condiçöes ovarianas e foliculares. A duraçäo média do ciclo estral foi de 24,24ñ6,00 dias com 7,50ñ4,16 dias de estro. Observou-se que o início do estro foi mais freqüente às 12 h do que às 8 h ou 16 h e que as ovulaçöes ocorreram 75 por cento à noite, estando distribuídas de igual maneira nos dois ovários. Notou-se, também, que a fase estral terminou em 85 por cento dos casos 24 horas após a ovulaçäo


Asunto(s)
Animales , Femenino , Estro , Caballos , Ovulación , Reproducción
17.
J Am Coll Cardiol ; 30(2): 343-9, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9247503

RESUMEN

OBJECTIVES: This study sought to determine the long-term effects of continuous infusion of epoprostenol (epo) therapy on survival and pulmonary artery pressure in patients with primary pulmonary hypertension (PPH). BACKGROUND: PPH is a progressive disease for which there are few effective therapies. METHODS: Patients with PPH and New York Heart Association functional class III or IV symptoms of congestive heart failure underwent right heart catheterization and Doppler-echocardiography to measure the maximal systolic pressure gradient between the right ventricle and right atrium (delta P) and cardiac output (CO). Doppler-echocardiography and catheterization data were compared. Patients were followed up long term with Doppler-echocardiography. RESULTS: Of 69 patients who went on to receive epo, 18 were followed up for > 330 days (range 330 to 700). During long-term follow-up, there was a significant reduction in delta P, which decreased from 84.1 +/- 24.1 to 62.7 +/- 18.2 (mean +/- SD, p < 0.01). A Kaplan-Meier plot of survival of our study patients demonstrated improved survival compared with that of historical control subjects. The 1-, 2- and 3-year survival rates for our patients were 80% (n = 36), 76% (n = 22) and 49% (n = 6) compared with 10- (88%, n = 31), 20- (56%, n = 27) and 30-month (47%, n = 17) survival rates in historical control subjects. CONCLUSIONS: Patients receiving continuous infusion of epo for treatment of PPH experience a decrease in pulmonary artery pressure. Long-term follow-up of this single-center patient group demonstrated improved long-term survival during epo therapy compared with that in historical control subjects and confirms predicted improved outcomes based on shorter follow-up periods.


Asunto(s)
Antihipertensivos/administración & dosificación , Epoprostenol/administración & dosificación , Hipertensión Pulmonar/tratamiento farmacológico , Adolescente , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Cateterismo Cardíaco , Gasto Cardíaco/efectos de los fármacos , Niño , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Hipertensión Pulmonar/mortalidad , Hipertensión Pulmonar/fisiopatología , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
18.
Arch Latinoam Nutr ; 45(3): 227-36, 1995 Sep.
Artículo en Español | MEDLINE | ID: mdl-9382683

RESUMEN

The efficiency of a wheat:soy mixture (85:15 ratio) with and without supplementation of the limitant amino acids (methionine and lysine), was evaluated for: a. Supporting the normal rat growth previously fed with a casein diet (control group). b. The rat recovering with early and later protein-calorie malnutrition, and c. The animals ability (control and malnourished groups) in the self-selection for the limitant amino acids given. It was shown that the test diet, with and without supplementation, was adequate to sustain a normal body nitrogen content increase of the control groups animals. The principal changes in rat weight of the experimental animals during the recovering period were dependent on the nutritional state and the quantity of both, diet and amino acids intakes. As the age of rats increased, the diet intake (expressed as g of diet intake/100 g of rat) decreased in all experimental groups; this effect being more noticeable in malnourished groups. The self-selected intake of lysine and methionine, depends on: the previous nutritional state and the period of undernutrition of the animals; higher intake than the standard required values (Rogers and Harper) was observed in the three experimental groups. It was shown that the amount of methionine (gr met intake/100 g of wheat mixture) was directly related to lysine intake, expressed in similar units; significant correlation was observed: r = 0.816 (control group) and r = 0.789 (later malnutrition group) and highly significative r = 0.996 (early malnutrition group). The increase of the ratio between total body nitrogen and its initial value, was significative in all the cases. However the effect was more pronounced when the results obtained with early-malnutrition group are analyzed. The experiments performed with later malnutrition groups revealed that the increase of body nitrogen content was higher for supplemented diets than for animals fed with no-supplemented mixtures (the observed difference was highly significative p < 0.01). The analysis of body lipid content showed that the relative increase was much more significative for early malnourished groups. However in all the cases the effect of amino acid supplementation is almost negligible.


Asunto(s)
Dietoterapia , Trastornos Nutricionales/tratamiento farmacológico , Desnutrición Proteico-Calórica/tratamiento farmacológico , Verduras , Animales , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Modelos Animales de Enfermedad , Minerales/administración & dosificación , Ratas , Ratas Wistar
19.
Int J Tissue React ; 14(5): 225-30, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1300308

RESUMEN

Many vasal factors are produced during an experimental model of inflammation such as rat-paw oedema induced by carrageenin. We investigated whether among the other well-known mediators of inflammation, i.e. serotonin, PAF, eicosanoids and kinins, the peptide endothelin-1 is produced by this kind of inflammatory process caused by carrageenin. Our results indicated that plasma endothelin, and the tissue concentration of endothelin in the oedematous paw, is increased as compared to the control. Consequently, endothelin should also be considered as an important factor in inflammatory processes.


Asunto(s)
Endotelinas/fisiología , Inflamación/metabolismo , Animales , Carragenina , Endotelinas/metabolismo , Inflamación/inducido químicamente , Radioinmunoensayo , Ratas , Ratas Wistar , Valores de Referencia
20.
Arch Latinoam Nutr ; 37(3): 503-14, 1987 Sep.
Artículo en Español | MEDLINE | ID: mdl-3506404

RESUMEN

Binary sorghum:soy (70:30) and ternary sorghum:corn:soy (30:40:30) blends using high and low tannin content dehulled sorghum were extruded. The effectiveness of heat treatment was determined by protein dispersion index (PDI) and ureasic activity (delta PH), indicating that proteins were denatured and antinutritional factors reduced. The nutritional evaluation supported the fact that samples were adequately treated, giving ternary blends true digestibility (TD) and biological values (BV) similar to milk casein. Blend stabilities, expressed as peroxide index (PI), revealed a low lipid oxidation rate during the first seven months, and were acceptable up to a year of storage. Extrudates with incorporated sorghum cover protein and energy demands of the growing infant, and provide a high nutritional value and long-life product.


Asunto(s)
Grano Comestible , Conservación de Alimentos , Tecnología de Alimentos , Alimentos Formulados , Glycine max , Animales , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Proteínas en la Dieta/análisis , Femenino , Alimentos Formulados/análisis , Calor , Humanos , Masculino , Valor Nutritivo , Ratas , Ratas Endogámicas
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