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1.
Catheter Cardiovasc Interv ; 88(5): 740-747, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26833916

RESUMEN

OBJECTIVES: This study sought to assess the impact of residual coronary artery disease (CAD), using the residual SYNTAX score (rSS), on in-hospital outcomes after primary percutaneous intervention (PPCI). The study also aimed to determine independent predictors for high rSS. Residual CAD has been associated with worsened prognosis in patients undergoing PCI for non-ST acute coronary syndromes. The rSS is a systematic angiographic score that measures the extent and complexity of residual CAD after PCI. MATERIALS AND METHODS: Data from 243 consecutive patients undergoing PPCI for ST-elevation myocardial infarction (STEMI) were analyzed. The rSS was derived from post-PPCI angiography. Patients were dichotomized into low (<8) and high rSS (≥8) groups and outcomes were compared between groups. The primary outcome of net adverse cardiovascular events (NACE) consisted of a composite of in-hospital death, congestive heart failure (CHF), recurrent MI and bleeding. RESULTS: The mean rSS was 4.7 (±7.2). A high rSS was associated with the primary outcome (P < 0.0001), in-hospital death (P = 0.0026), periprocedural death (P < 0.0001), CHF (P < 0.0004) and acute kidney injury (P < 0.0019). A high rSS was also an independent predictor of the primary outcome with an OR of 3.82. Independent predictors of a high rSS included a history of diabetes (OR 2.8), previous MI (OR 5.75), 2-vessel disease (VD) (OR 15.48, vs. 1-VD) and 3-VD (OR 57.06, vs. 1-VD). CONCLUSIONS: Residual CAD, as assessed by the rSS, confers a worsened prognosis in patients undergoing PPCI. Diabetes, previous MI and multi-vessel disease were independent predictors of a high rSS. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Intervención Coronaria Percutánea/métodos , Complicaciones Posoperatorias/epidemiología , Infarto del Miocardio con Elevación del ST/cirugía , Anciano , Angiografía Coronaria , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria/tendencias , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Quebec/epidemiología , Infarto del Miocardio con Elevación del ST/diagnóstico , Factores de Tiempo
2.
Climacteric ; 18(6): 817-25, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26517756

RESUMEN

OBJECTIVE: The aim was to analyze the opinion of the male partner of women treated for vulvovaginal atrophy (VVA) with intravaginal 0.50% DHEA (prasterone), thus providing information on both members of the couple. METHODS: On a voluntary basis, in a prospective, randomized, double-blind and placebo-controlled phase-III clinical trial, the male partner filled a questionnaire at baseline and at 12 weeks stating his observations related to his penis and intercourse before and after VVA treatment. RESULTS: Sixty-six men having a partner treated with intravaginal DHEA and 34 others having a partner treated with placebo answered the questionnaires. Concerning the feeling of vaginal dryness of their female partner, the severity score following DHEA treatment improved by 81% (0.76 units) over placebo (p = 0.0347). Thirty-six percent of men having a partner treated with DHEA did not feel the vaginal dryness of the partner at the end of treatment compared to 7.8% in the placebo group. When analyzing the situation at 12 weeks compared to baseline, an improved score of 1.09 units was the difference found for the DHEA group compared to 0.76 for the placebo group (p = 0.05 vs. placebo). In the DHEA group, 38% of men scored very improved compared to 18% in the placebo group. No adverse event has been reported. CONCLUSION: The male partner had a very positive evaluation of the treatment received by his female partner.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Deshidroepiandrosterona/administración & dosificación , Enfermedades del Pene/etiología , Parejas Sexuales , Vagina/patología , Vulva/patología , Administración Intravaginal , Adulto , Anciano , Anciano de 80 o más Años , Atrofia/complicaciones , Atrofia/tratamiento farmacológico , Coito , Método Doble Ciego , Dispareunia/etiología , Eritema/etiología , Femenino , Fricción/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensación/efectos de los fármacos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Resultado del Tratamiento , Vagina/efectos de los fármacos , Vulva/efectos de los fármacos
3.
Climacteric ; 18(4): 590-607, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25511551

RESUMEN

OBJECTIVE: While daily intravaginal administration of 0.50% (6.5 mg) dehydroepiandrosterone (DHEA, prasterone) for 12 weeks has shown clinically and statistically significant effects on moderate to severe (MS) dyspareunia as the most bothersome symptom (MBS), the present study analyzes the effect of a reduced dosing regimen on MBS vaginal dryness. METHOD: Daily intravaginal 0.50% prasterone for 2 weeks followed by twice weekly for 10 weeks versus placebo. RESULTS: Maximal beneficial changes in vaginal parabasal and superficial cells and pH were observed at 2 weeks as observed for intravaginal 10 µg estradiol (E2). This was followed by a decrease or lack of efficacy improvement after switching to twice-weekly dosing. The decrease in percentage of parabasal cells, increase in percentage of superficial cells and decrease in vaginal pH were all highly significant (p < 0.0001 to 0.0002 over placebo) at 12 weeks. In parallel, the statistical significance over placebo (p value) on MBS vaginal dryness at 6 weeks was 0.09 followed by an increase to 0.198 at 12 weeks. For MBS dyspareunia, the p value of 0.008 at 6 weeks was followed by a p value of 0.077 at 12 weeks, thus illustrating a decrease of efficacy at the lower dosing regimen. The improvements of vaginal secretions, color, epithelial integrity and epithelial surface thickness were observed at a p value < 0.01 or 0.05 over placebo at 2 weeks, with a similar or loss of statistical difference compared to placebo at later time intervals. No significant adverse event was observed. Vaginal discharge related to the melting of Witepsol was reported in 1.8% of subjects. CONCLUSION: The present data show that daily dosing with 0.50% DHEA for 2 weeks followed by twice-weekly dosing is a suboptimal treatment of the symptoms/signs of vulvovaginal atrophy resulting from a substantial loss of the efficacy achieved at daily dosing.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Deshidroepiandrosterona/administración & dosificación , Enfermedades Vaginales/tratamiento farmacológico , Enfermedades de la Vulva/tratamiento farmacológico , Adyuvantes Inmunológicos/uso terapéutico , Administración Intravaginal , Adulto , Anciano , Atrofia/complicaciones , Atrofia/tratamiento farmacológico , Deshidroepiandrosterona/uso terapéutico , Método Doble Ciego , Esquema de Medicación , Dispareunia/tratamiento farmacológico , Dispareunia/etiología , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Resultado del Tratamiento , Enfermedades Vaginales/complicaciones , Enfermedades de la Vulva/complicaciones
4.
Transfus Med ; 23(1): 55-60, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23167310

RESUMEN

OBJECTIVE: The objective of this study is to evaluate the economic benefits of immunoglobulin replacement therapy achieved subcutaneously (subcutaneous immunoglobulin, SCIG) by the rapid push method compared to intravenous infusion therapy (intravenous immunoglobulin, IVIG) in primary immune deficiency (PID) patients from the healthcare system perspective in the context of the adult SCIG home infusion program based at St Paul's Hospital, Vancouver, Canada. MATERIALS AND METHODS: SCIG and IVIG options were compared in cost-minimisation and budget impact models (BIMs) over 3 years. Sensitivity analyses were performed for both models to evaluate the impact of varying modality of IVIG treatments and proportion of patients switching from IVIG to SCIG. RESULTS: The cost-minimisation model estimated that SCIG treatment reduced cost to the healthcare system per patient of $5736 over 3 years, principally because of less use of hospital personnel. This figure varied between $5035 and $8739 depending on modality of IVIG therapy. Assuming 50% of patients receiving IVIG switched to SCIG, the BIM estimated cost savings for the first 3 years at $1·308 million or 37% of the personnel and supply budget. These figures varied between $1·148 million and $2·454 million (36 and 42%) with varying modalities of IVIG therapy. If 75% of patients switched to SCIG, the reduced costs reached $1·962 million or 56% of total budget. CONCLUSION: This study demonstrated that from the health system perspective, rapid push home-based SCIG was less costly than hospital-based IVIG for immunoglobulin replacement therapy in adult PID patients in the Canadian context.


Asunto(s)
Inmunización Pasiva/métodos , Inmunoglobulinas Intravenosas/uso terapéutico , Síndromes de Inmunodeficiencia/terapia , Adulto , Colombia Británica , Presupuestos/estadística & datos numéricos , Ahorro de Costo/estadística & datos numéricos , Gastos en Salud/estadística & datos numéricos , Servicios de Atención a Domicilio Provisto por Hospital/economía , Costos de Hospital/estadística & datos numéricos , Humanos , Inmunización Pasiva/economía , Inmunoglobulinas Intravenosas/economía , Síndromes de Inmunodeficiencia/economía , Infusiones Intravenosas/economía , Inyecciones Subcutáneas/economía , Salarios y Beneficios/estadística & datos numéricos
5.
Climacteric ; 14(2): 282-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21244215

RESUMEN

OBJECTIVE: To examine the effect of intravaginal dehydroepiandrosterone (DHEA) on pain at sexual activity (dyspareunia) identified as the most bothersome symptom of vaginal atrophy in postmenopausal women at both screening and day 1. METHODS: This prospective, randomized, double-blind and placebo-controlled phase III clinical trial studied the effect of prasterone (DHEA) applied locally in the vagina on the severity of dyspareunia in 114 postmenopausal women who had identified dyspareunia as their most bothersome symptom of vaginal atrophy, while meeting the criteria for superficial cells ≤ 5% and pH > 5.0 at both screening and day 1. RESULTS: At the standard duration of 12 weeks of treatment, increasing doses of 0.25%, 0.5% and 1.0% DHEA decreased the percentage of parabasal cells by 48.6  ±â€Š 6.78%, 42.4  ±  7.36% and 54.9  ±â€Š 6.60% (p < 0.0001 vs. placebo for all) with no change with placebo (p = 0.769). The effects on superficial cells and pH were also highly significant compared to placebo at all DHEA doses. The severity score of pain at sexual activity decreased by 0.5, 1.4, 1.6 and 1.4 units in the placebo and 0.25%, 0.5% and 1.0% DHEA groups, respectively, with the p value of differences from placebo ranging from 0.0017 to < 0.0001. CONCLUSIONS: Intravaginal DHEA, through local estrogen and androgen formation, causes a rapid and highly efficient effect on pain at sexual activity without systemic exposure of the other tissues, thus avoiding the recently reported systemic effects of estrogens.


Asunto(s)
Deshidroepiandrosterona/administración & dosificación , Dispareunia/tratamiento farmacológico , Administración Intravaginal , Deshidroepiandrosterona/uso terapéutico , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Posmenopausia , Resultado del Tratamiento
6.
Diabetes ; 42(2): 363-6, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8381096

RESUMEN

The specific effect of hyperglycemia on the reported decrease in liver glycogen synthase phosphatase activity was studied in STZ-induced diabetic rats with normal fasting insulinemia. Four groups of animals were investigated: control (nondiabetic), diabetic hyperglycemic (STZ), diabetic normoglycemic (STZ followed by 3-day phloridzin treatment), and a diabetic normoglycemic group injected with glucose to reinstate hyperglycemia. None of the treatments significantly altered fasting plasma insulin and glucagon concentrations. We found that hepatic synthase phosphatase activity decreased in STZ-induced diabetic rats and was further markedly reduced when glycemia was normalized in the diabetic animals. This additional decrease in phosphatase activity was almost fully reversed when hyperglycemia was restored by acute glucose infusion of the normoglycemic diabetic rats. In parallel, the levels of liver G6P and F6P were markedly reduced in the diabetic normoglycemic rats and restored with reinstatement of hyperglycemia. In contrast, liver microsomal glucose-6-phosphatase activity was enhanced and glucokinase activity was lowered in all diabetic groups, regardless of glycemia. Our results indicate that hyperglycemia per se counteracts part of the loss of hepatic synthase phosphatase in diabetic animals and provokes the stable conversion of synthase phosphatase from a less active to a more active form.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Experimental/enzimología , Glucógeno Sintasa-D Fosfatasa/metabolismo , Hiperglucemia/enzimología , Insulina/fisiología , Hígado/enzimología , Florizina/farmacología , Animales , Diabetes Mellitus Experimental/sangre , Glucagón/sangre , Glucoquinasa/metabolismo , Glucosa/farmacología , Glucosa-6-Fosfatasa/metabolismo , Hexosafosfatos/metabolismo , Hiperglucemia/etiología , Insulina/sangre , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
7.
Endocrinology ; 129(5): 2674-8, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1935796

RESUMEN

Addition of 60 mM glucose caused a similar partial activation of glycogen synthase in hepatocytes isolated from overnight fasted Wistar rats and from fasted lean Zucker (Fa/fa?) rats. In contrast, the activation went rapidly to completion in cells from fasted obese (fa/fa) rats. Subsequent addition of 4 microM microcystin, a potent inhibitor of type 1 and type 2A protein phosphatases, induced a rapid inactivation of glycogen synthase, which occurred at a similar rate in all three types of hepatocytes. This suggests that the super-activation of glycogen synthase in hepatocytes from fasted obese rats is not due to a lower synthase kinase activity. Glycogen synthase phosphatase was quantitatively assayed in broken-cell preparations from the same livers, with exogenous synthase b as substrate. The synthase phosphatase activity in the fa/fa livers was 3-fold higher than that in the livers from both lean Zucker rats and Wistar rats. This difference has to be attributed to an increased synthase phosphatase activity of the glycogen-bound protein phosphatase-1 in livers of fasted obese rats. The results suggest that in the latter animals the available insulin exceeds the insulin resistance of the liver. The resulting overexpression of the insulin-dependent synthase-phosphatase-1G activity may explain the super-activation of glycogen synthase in response to a glucose challenge.


Asunto(s)
Ayuno , Glucógeno Sintasa/metabolismo , Glucógeno Sintasa-D Fosfatasa/metabolismo , Hígado/enzimología , Obesidad/enzimología , Animales , Activación Enzimática , Glucosa/farmacología , Glucógeno Sintasa/farmacología , Hígado/patología , Toxinas Marinas , Microcistinas , Obesidad/patología , Péptidos Cíclicos/farmacología , Proteína Fosfatasa 1 , Ratas , Ratas Zucker
8.
FEBS Lett ; 366(2-3): 109-14, 1995 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-7789525

RESUMEN

The GLUT4 glucose transporter and the alpha 2 subunit of the Na+,K(+)-ATPase of rat skeletal muscle are two proteins which redistribute from intracellular membranes to plasma membranes following in vivo insulin stimulation. Here we show that although both proteins co-segregate after subcellular fractionation of unstimulated rat hindlimb muscles, they do not share the same intracellular residence inside the muscle fibre. By immunogold single- and double-labeling on ultrathin muscle cryosections with specific antibodies, the GLUT4 glucose transporter and the Na+,K(+)-ATPase alpha 2 subunit were observed on different vesicular structures within the cell. GLUT4 was detected on subsarcolemmal and perinuclear membranes, and at the junction between myofibrillar A and I bands where triads are localized. The alpha 2 subunit of the Na+,K(+)-ATPase was observed at the plasma membrane and in distinct subsarcolemmal vesicles and intermyofibrillar membranes. Quantitative analysis of double-labeling of GLUT4 and Na+,K(+)-ATPase alpha 2 subunit revealed that less than 6% of the two proteins co-localize in the same continuous vesicular structures. The differential intracellular localization of the two proteins was further confirmed by immunopurification of GLUT4-containing membranes from muscle homogenates, in which the alpha 2 subunit of the Na+,K(+)-ATPase was found only at the same extent as the alpha 1 subunit of the enzyme, a protein exclusively present at the plasma membrane.


Asunto(s)
Proteínas de Escherichia coli , Glicósido Hidrolasas , Membranas Intracelulares/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas Musculares/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Proteínas Bacterianas/química , Transportador de Glucosa de Tipo 4 , Glicosiltransferasas/química , Inmunohistoquímica , Insulina/farmacología , Masculino , Datos de Secuencia Molecular , Músculos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Fracciones Subcelulares/química
9.
Am J Cardiol ; 73(2): 191-4, 1994 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8296742

RESUMEN

Percutaneous ablation of accessory pathways was performed in 22 consecutive children and adolescents (9 boys and 13 girls, age range 8 to 18 years). Low-energy direct current (DC) was used exclusively in the first 6 patients, whereas ablation was performed with radiofrequency energy in the following 16. Accessory pathways were located in the left free wall in 15 patients, were posteroseptal in 3, were in the right free wall in 3 and were anteroseptal in 1. A concealed accessory pathway was present in 7 patients (32%). There was no significant difference in clinical or electrophysiologic variables between both groups. Catheter ablation was successful in the initial 6 patients using low-energy DC, as compared with 13 of 16 patients using radiofrequency ablation. Low-energy DC was successful as a backup power source in all 3 patients who had unsuccessful radiofrequency ablation. There was no complication. The median procedural and fluoroscopic times for successful ablation were 2.5 hours and 49 minutes, respectively (p = NS between both power sources). Accessory pathway conduction recurred in 2 patients (33%) who had low-energy DC as compared with 1 (6%) who had radiofrequency ablation (p = NS). These 3 patients had successful reablation of their accessory pathways. In children and adolescents with accessory pathways, both new power sources compare favorably, with an overall success rate of ablation of 100% (22 of 22 patients). Radiofrequency ablation should be used initially because it does not require general anesthesia and is associated with a lower rate of recurrence of accessory pathway conduction.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Ablación por Catéter/métodos , Síndrome de Wolff-Parkinson-White/cirugía , Adolescente , Niño , Femenino , Sistema de Conducción Cardíaco/fisiopatología , Sistema de Conducción Cardíaco/cirugía , Humanos , Masculino , Resultado del Tratamiento , Síndrome de Wolff-Parkinson-White/fisiopatología
10.
Mol Cell Endocrinol ; 173(1-2): 15-27, 2001 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-11223174

RESUMEN

Grb10 is a member of a family of adapter proteins that binds to tyrosine-phosphorylated receptors including the insulin receptor kinase (IRK). In this study recombinant adenovirus was used to over-express hGrb10zeta, a new Grb10 isoform, in primary rat hepatocytes and the consequences for insulin signaling were evaluated. Over-expression of hGrb10zeta resulted in 50% inhibition of insulin-stimulated IRK autophosphorylation and activation. Analysis of downstream events showed that hGrb10zeta over-expression specifically inhibits insulin-stimulated glycogen synthase (GS) activity and glycogen synthesis without affecting insulin-induced IRS1/2 phosphorylation, PI3-kinase activation, insulin like growth factor binding protein-1 (IGFBP-1) mRNA expression, and ERK1/2 MAP kinase activity. The classical pathway from PI3-kinase through Akt-PKB/GSK-3 leading to GS activation by insulin was also not affected by hGrb10zeta over-expression. These results indicate that hGrb10zeta inhibits a novel and presently unidentified insulin signaling pathway leading to GS activation in liver.


Asunto(s)
Glucógeno Sintasa/metabolismo , Insulina/farmacología , Proteínas/metabolismo , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Proteína Adaptadora GRB10 , Glucógeno/biosíntesis , Glucógeno Sintasa Quinasa 3 , Hepatocitos/efectos de los fármacos , Hepatocitos/enzimología , Hepatocitos/metabolismo , Humanos , Insulina/metabolismo , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Compuestos Organometálicos/farmacología , Fenantrolinas/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Proteínas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Insulina/antagonistas & inhibidores , Receptor de Insulina/metabolismo , Transducción de Señal/efectos de los fármacos , Transcripción Genética/efectos de los fármacos
11.
Metabolism ; 40(10): 1031-6, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1658543

RESUMEN

The contribution of hormone-stimulated glycogenolysis to hepatic glucose production was studied in hepatocytes from streptozotocin diabetic rats. To this end, the activation of glycogen phosphorylase by glucagon, vasopressin, and the alpha 1-adrenergic agonist phenylephrine was compared in hepatocytes from normal and diabetic rats and related to glycogen content, glucose production, and microsomal glucose-6-phosphatase activity. Streptozotocin-induced diabetes reduced the glycogen content and the amount of total (a + b) phosphorylase in hepatocytes proportionally to the severity of the disease. In cells from severely diabetic rats (group 1), the responsiveness of activation of phosphorylase to the hormones was reduced by about half, consistent with a 45% reduction in total phosphorylase. In addition, the sensitivity of phosphorylase activation to all hormones investigated was decreased by about 1 order of magnitude or more in cells of this group. In hepatocytes from rats with milder diabetes (group 2), maximal phosphorylase activation reached an intermediate value between that of the control group and of group 1. In response to all hormones investigated, group 2 diabetic rat hepatocytes produced less glucose than control rat liver cells, while in group 1 there was no increase in glucose production at all, presumably because glycogen concentration was too low. However, in group 2 diabetic rat hepatocytes, glucagon-stimulated glucose production, unlike phosphorylase activation, did not show decrease sensitivity, presumably because glucose-6-phosphatase activity is increased by diabetes. Our results thus indicate that hormone-stimulated liver glycogenolysis is unlikely to contribute to enhanced glucose production in insulin-deficient diabetes, despite increased glucose-6-phosphatase activity.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Glucosa/biosíntesis , Glucógeno/metabolismo , Hígado/metabolismo , Animales , Diabetes Mellitus Experimental/patología , Activación Enzimática/efectos de los fármacos , Glucagón/farmacología , Glucosa-6-Fosfatasa/metabolismo , Hormonas/farmacología , Hígado/patología , Microsomas/enzimología , Fenilefrina/farmacología , Fosforilasas/metabolismo , Valores de Referencia , Vasopresinas/farmacología
12.
Med Phys ; 3(5): 283-93, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-979917

RESUMEN

The current understanding of xenon scintillation physics is summarized and keyed to the use of xenon as a gamma-ray detector in medical radioisotope imaging systems. Liquid xenon has a short scintillation pulse (approximately 10(8) sec) and high gamma-ray absorption and scintillation efficiencies. The fast pulse may facilitate imaging in vivo distributions of hot positron sources and allow recovery of additional spatial information by time-of-flight techniques. We begin by describing our own study of the feasibility of making a practical positron scanning system, and consider the problems of scintillation decay time, linearity, efficiency, purity, and electricfield amplifcation. The prospects for a practical instrument are considered.


Asunto(s)
Cintigrafía/instrumentación , Xenón
13.
Physiol Behav ; 52(2): 237-40, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1523247

RESUMEN

It has been reported that insulin concentration is altered by a hepatic vagotomy following intraperitoneal glucose injection (0.3 g/kg) resulting in supraphysiological blood glucose concentrations. On the other hand, neural activity of the hepatic vagus nerve has been shown to be substantially reduced by lower doses (0.05 g/kg intraportal; 0.1 g/kg intravenous). The present study was conducted in order to examine the role of the hepatic vagus nerve in insulin response after intraperitoneal injections of 0.1 and 0.3 g/kg of glucose. Measurements were made 5 days after section of this branch. In a first experiment, arterial glucose and insulin concentrations were not affected by the hepatic vagotomy following injections of either 0.1 or 0.3 g/kg of glucose. The same finding was also found in a second experiment in which portal glucose and insulin levels were measured after injection of 0.1 g/kg of glucose. These results suggest that large changes in neural activity are needed for the hepatic vagus nerve to influence the insulin response.


Asunto(s)
Glucosa/farmacología , Insulina/sangre , Hígado/fisiología , Vagotomía , Animales , Glucemia/metabolismo , Hígado/inervación , Masculino , Neuronas Aferentes/fisiología , Ratas , Ratas Endogámicas
14.
J Rehabil Res Dev ; 25(3): 41-50, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2970542

RESUMEN

Two congenitally profoundly deaf adults were trained to perceive words through the Tacticon 1600 electrocutaneous vocoder, an artificial hearing prosthesis. The subjects learned to identify 50 words during 47 hours (Subject One) and 41 hours (Subject Two) of training, with a 41.6 percent rate of success across all sessions. Both subjects showed consistent error patterns during the training phase. Analysis of these error patterns suggested that they were employing word identification strategies based on some general aspects of tactual patterns. Specific characteristics of the tactual patterns that they appeared to be using included: syllable number, tactual locus of word ending, direction of pattern movement, and position of bursts (/t/, /k/, /d/, for example). Following training, the subjects were tested for their abilities to integrate tactual and aided-auditory cues in word identification. Three conditions of aided-audition alone (A), tactual vocoder alone (TV), and aided-audition with tactual vocoder (TV + A) were used. The stimulus-word list for this phase consisted of the 50 words acquired in tactual vocoder training, and 50 "tactually-new" words, i.e., words that had not been presented to them in tactual vocoder training sessions. They correctly identified 93 percent (Subject One) and 56 percent (Subject Two) more trials in the TV + A condition than in the A condition. Tactually-new vocabulary was correctly identified 78 percent (Subject One) and 50 percent (Subject Two) more often when sensory modalities were combined, than when only aided-audition was used. Subjects identified tactually-new vocabulary better than chance in the TV condition.


Asunto(s)
Equipos de Comunicación para Personas con Discapacidad , Sordera/rehabilitación , Dispositivos de Autoayuda , Percepción del Habla , Adulto , Sordera/congénito , Estimulación Eléctrica , Femenino , Respuesta Galvánica de la Piel , Humanos , Masculino , Vocabulario
15.
EuroIntervention ; 5(6): 716-21, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20142224

RESUMEN

AIMS: Mortality of massive pulmonary embolism remains exceedingly high despite thrombolytic therapy. Despite initial encouraging results, rheolytic thrombectomy has not been considered the first choice of treatment in the current European Guidelines for massive pulmonary embolism, even in cases of major contraindication to thrombolysis. Our objective was to assess the efficacy of rheolytic thrombectomy in the specific treatment of massive pulmonary embolism with contraindication to systemic thrombolytic therapy. METHODS AND RESULTS: Between January 2003 and April 2008 a total of 10 patients with massive pulmonary embolism referred for rheolytic thrombectomy were included. Clinical data including medical history, haemodynamic status, procedural characteristic, in-hospital complications and survival were collected. Seven patients survived after undergoing the procedure, three patients died in during their initial hospitalisation however, two of these deaths were not attributable to the pulmonary embolism or the procedure. Rheolytic thrombectomy resulted in reduction of mean pulmonary artery pressures from 34.6+/-13.1 mmHg to 26.9+/-8.2 mmHg immediately following the procedure. Additionally, the Miller index improved from 22.4+/-2.8 to 9.8+/-2.7. There were no periprocedural bleeding complications associated with the procedure. CONCLUSIONS: Rheolytic thrombectomy might be an effective and safe treatment for massive pulmonary embolism when systemic thrombolytic therapy is contraindicated. These data form the basis for further clinical investigation of this novel therapy among patients with massive pulmonary embolism.


Asunto(s)
Embolia Pulmonar/cirugía , Trombectomía/instrumentación , Terapia Trombolítica , Adolescente , Adulto , Anciano , Contraindicaciones , Ecocardiografía Doppler , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
17.
Phys Med Biol ; 16(2): 334, 1971 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-5581639
19.
Biochemistry ; 36(25): 7726-32, 1997 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-9201913

RESUMEN

The Na+-K+-ATPase consists of alpha and beta subunits proposed to function as an alpha-beta heterodimer. Skeletal muscle is characterized by expression of alpha1, alpha2, beta1, and beta2 subunit isoforms. The relative molar proportions of each subunit or each protein isoform are not known, yet their subcellular distribution and expression in muscles of different fiber types are markedly different. In this study, the molar ratio of each pump subunit isoform was measured in purified membranes from skeletal muscle and compared with those in kidney and brain microsomes. Recombinant proteins were used as standards to quantitate each isoform by immunoblotting in combination with measurements of [3H]ouabain binding. The results indicate that in kidney microsomes, which express predominantly alpha1 and beta1 isoforms, the alpha:beta subunit molar ratio is approximately 1:1. In brain microsomes, the sum of all alpha (alpha1, alpha2, and alpha3) and all beta (beta1 and beta2) subunits also yielded a molar ratio of approximately 1:1. In contrast, in red (oxidative) skeletal muscles, the all alpha:beta subunit ratio was 0.2 in plasma membranes and 0.4 in intracellular membranes. The ratio of alpha2 subunits to alpha1 subunits ranged from 1.6 in surface membranes to up to 7 in internal membranes, while the beta1 subunits exceeded the beta2 subunits by approximately 4-fold in all membrane fractions. Thus, intracellular membranes of red skeletal muscles contain primarily alpha2 and beta1 subunits. When these intracellular membranes were further subfractionated by velocity gradient centrifugation, the alpha2:beta1 subunit ratio was 0.5 in the faster migrating (larger) membranes and 1.0 in the slower migrating (smaller) ones. This was due to a progressive decrease in abundance of the beta1 subunits without a change in the concentration of alpha2 subunits per unit protein. The Na+-K+-ATPase hydrolytic activity was higher in the larger vesicles than in the smaller ones along the sucrose gradient. These results suggest that the ratio of beta to alpha subunits may serve to regulate the catalytic activity of the Na+-K+-ATPase in skeletal muscle.


Asunto(s)
Membranas Intracelulares/enzimología , Músculo Esquelético/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Fraccionamiento Celular , Músculo Esquelético/ultraestructura , Ratas
20.
J Biol Chem ; 267(6): 3632-6, 1992 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-1740415

RESUMEN

We have investigated the role of a glutathione S-transferase (GST) with inherent peroxidase activity in the cellular defense against lipid peroxidation and free radical-mediated oxidative damage. Stable transfectants of human T47D cells were generated which express recombinant rat GST-Yc from a human cytomegalovirus promoter-based expression vector. Among several GST-Yc transfectants characterized, two of them contained, respectively, 2- and 3-fold higher GST activity than parental cells or control transfectants and, respectively, 4-5- and 8-10-fold higher selenium-independent glutathione peroxidase activity. Cellular growth kinetics and rates of [3H]thymidine incorporation showed that both transfectants were more resistant to oxidative shocks mediated by cumene hydroperoxide or singlet oxygen generated by photosensitized rose bengal than were T47D cells and control transfectants. In contrast, a T47D transfectant, which expressed high levels of recombinant selenoglutathione peroxidase and showed enhanced resistance to cumene hydroperoxide (Mirault, M.-E., Tremblay, A., Beaudoin, N., and Tremblay, M. J. (1991) J. Biol. Chem. 266, 20752-20760), was as sensitive as parental cells to singlet oxygen. No difference was found in growth sensitivity to 1-h shock treatments with the quinonoid drug daunomycin, irrespective of GST-Yc or selenoglutathione peroxidase overexpression in these cells.


Asunto(s)
Glutatión Transferasa/genética , Peroxidación de Lípido , Animales , Antioxidantes , Derivados del Benceno/farmacología , Ciclo Celular , Línea Celular , ADN/metabolismo , Electroforesis en Gel de Poliacrilamida , Radicales Libres , Vectores Genéticos , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Humanos , Fenotipo , Ratas , Proteínas Recombinantes/metabolismo , Rosa Bengala/farmacología , Timidina/metabolismo , Transfección
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