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1.
Ultrasound Obstet Gynecol ; 62(2): 248-254, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36971026

RESUMEN

OBJECTIVE: To examine the relationship between umbilical cord insertion site, placental pathology and adverse pregnancy outcome in a cohort of normal and complicated pregnancies. METHODS: Sonographic measurement of the cord insertion and detailed placental pathology were performed in 309 participants. Associations between cord insertion site, placental pathology and adverse pregnancy outcome (pre-eclampsia, preterm birth, small-for-gestational age) were examined. RESULTS: A total of 93 (30%) participants were identified by pathological examination to have a peripheral cord insertion site. Only 41 of the 93 (44%) peripheral cords were detected by prenatal ultrasound. Peripherally inserted cords were associated significantly (P < 0.0001) with diagnostic placental pathology (most commonly with maternal vascular malperfusion (MVM)); of which 85% had an adverse pregnancy outcome. In cases of isolated peripheral cords, without placental pathology, the incidence of adverse outcome was not statistically different when compared to those with central cord insertion and no placental pathology (31% vs 18%; P = 0.3). A peripheral cord with an abnormal umbilical artery (UA) pulsatility index (PI) corresponded to an adverse outcome in 96% of cases compared to 29% when the UA-PI was normal. CONCLUSIONS: This study demonstrates that peripheral cord insertion is often part of the spectrum of findings of MVM disease and is associated with adverse pregnancy outcome. However, adverse outcome was uncommon when there was an isolated peripheral cord insertion and no placental pathology. Therefore, additional sonographic and biochemical features of MVM should be sought when a peripheral cord is observed. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta , Resultado del Embarazo , Cordón Umbilical , Femenino , Humanos , Recién Nacido , Embarazo , Placenta/patología , Nacimiento Prematuro , Arterias Umbilicales/diagnóstico por imagen , Cordón Umbilical/diagnóstico por imagen , Cordón Umbilical/patología
2.
Cytokine ; 96: 274-278, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28554144

RESUMEN

Excessive inflammation reduces skeletal muscle protein synthesis leading to wasting and weakness. The janus kinase/signal transducers and activators of transcription-3 (JAK/STAT3) pathway is important for the regulation of inflammatory signaling. As such, suppressor of cytokine signaling-3 (SOCS3), the negative regulator of JAK/STAT signaling, is thought to be important in the control of muscle homeostasis. We hypothesized that muscle-specific deletion of SOCS3 would impair the anabolic response to leucine during an inflammatory insult. Twelve week old (n=8 per group) SOCS3 muscle-specific knockout mice (SOCS3-MKO) and littermate controls (WT) were injected with lipopolysaccharide (LPS, 1mg/kg) or saline and were studied during fasted conditions or after receiving 0.5g/kg leucine 3h after the injection of LPS. Markers of inflammation, anabolic signaling, and protein synthesis were measured 4h after LPS injection. LPS injection robustly increased mRNA expression of inflammatory molecules (Socs3, Socs1, Il-6, Ccl2, Tnfα and Cd68). In muscles from SOCS3-MKO mice, the Socs3 mRNA response to LPS was significantly blunted (∼6-fold) while STAT3 Tyr705 phosphorylation was exacerbated (18-fold). Leucine administration increased protein synthesis in both WT (∼1.6-fold) and SOCS3-MKO mice (∼1.5-fold) compared to basal levels. LPS administration blunted this effect, but there were no differences between WT and SOCS3-MKO mice. Muscle-specific SOCS3 deletion did not alter the response of AKT, mTOR, S6 or 4EBP1 under any treatment conditions. Therefore, SOCS3 does not appear to mediate the early inflammatory or leucine-induced changes in protein synthesis in skeletal muscle.


Asunto(s)
Anabolizantes , Inflamación/metabolismo , Leucina/administración & dosificación , Músculo Esquelético/metabolismo , Biosíntesis de Proteínas , Proteína 3 Supresora de la Señalización de Citocinas/fisiología , Animales , Quimiocina CCL2/genética , Modelos Animales de Enfermedad , Interleucina-6/genética , Leucina/metabolismo , Lipopolisacáridos/administración & dosificación , Masculino , Ratones , Ratones Noqueados , Fosforilación , Factor de Transcripción STAT3/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/deficiencia , Proteína 3 Supresora de la Señalización de Citocinas/genética , Factor de Necrosis Tumoral alfa/genética
3.
Minerva Cardioangiol ; 63(3): 217-29, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25690178

RESUMEN

In the recent years it has become apparent that angiography-based assessment of coronary artery stenosis suffers from considerable inaccuracy and pitfalls. Besides interobserver variability in assessing stenosis severity, the correlation between angiographic severity and ischemia is suboptimal. Percutaneous coronary intervention (PCI) guided by the physiologic lesion assessment employing fractional flow reserve (FFR) is rendered superior to angiographic lesion assessment and proven to improve cardiovascular outcomes and reduce cost. In this manuscript we discuss the accepted and emerging clinical indications for FFR use. The correlation between FFR and symptoms, stress imaging and intravascular ultrasound are reviewed along with the inherent limitations and pitfalls of these diagnostic technologies. The data regarding the correlation between Instantaneous (vasodilator free) wave-free ratio (iFR) and conventional FFR is summarized.


Asunto(s)
Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico , Reserva del Flujo Fraccional Miocárdico , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/terapia , Humanos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatología , Variaciones Dependientes del Observador , Intervención Coronaria Percutánea/métodos , Índice de Severidad de la Enfermedad , Vasodilatadores/administración & dosificación
4.
Thromb Haemost ; 112(2): 323-31, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24763965

RESUMEN

Aspirin and statin therapy are mainstay treatments in patients with coronary artery disease (CAD). The relation between statin therapy, in vivo thromboxane (Tx) generation; a marker of inflammation, and blood thrombogenicity has never been explored. Urinary 11-dehydro (dh) TxB2 was determined in patients with suspected CAD on 325 mg daily aspirin therapy prior to undergoing cardiac catheterisation (n=281). Thrombogenicity was estimated by thrombelastographic measurement of thrombin-induced platelet-fibrin clot strength (TIP-FCS) and lipids/lipoproteins were determined by vertical density gradient ultracentrifugation/ELISA. The influence of statin therapy and dose was analysed by the atorvastatin equivalent dose (5-10 mg, 20-40 mg, or 80 mg daily). Statin therapy (n=186) was associated with a dose-dependent reduction in urinary 11-dh TxB2 (p=0.046) that was independent of LDL and apo B100 levels but was strongly related to TIP-FCS (p=0.006). By multivariate analysis, no statin therapy (n=95) and female gender were independently associated with high urinary 11-dh TxB2 [OR=2.95 (0.1.57-5.50, p=0.0007); OR=2.25 (1.24-4.05, p=0.007)], respectively. In aspirin-treated patients, statin therapy was independently and inversely associated with inflammation in a dose-dependent manner. Elevated 11-dh TxB2 was associated with a prothrombotic state indicated by high TIP-FCS. Our data suggest that measurement of urinary 11-dTxB2 may be a useful method to optimise statin dosing in order to reduce thrombotic risk.


Asunto(s)
Aspirina/administración & dosificación , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Mediadores de Inflamación/orina , Inhibidores de Agregación Plaquetaria/administración & dosificación , Tromboxano B2/análogos & derivados , Anciano , Biomarcadores/orina , Coagulación Sanguínea/efectos de los fármacos , Distribución de Chi-Cuadrado , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/orina , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Factores de Riesgo , Factores Sexuales , Tromboelastografía , Tromboxano B2/orina , Resultado del Tratamiento , Ultracentrifugación
5.
J Mol Cell Cardiol ; 65: 67-75, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24080183

RESUMEN

Cardiac metabolic stress is a hallmark of many cardiac pathologies, including diabetes. Cardiac glycogen mis-handling is a frequent manifestation of various cardiopathologies. Diabetic females have a higher risk of heart disease than males, yet sex disparities in cardiac metabolic stress settings are not well understood. Oestrogen acts on key glycogen regulatory proteins. The goal of this study was to evaluate sex-specific metabolic stress-triggered cardiac glycogen handling responses. Male and female adult C57Bl/6J mice were fasted for 48h. Cardiac glycogen content, particle size, regulatory enzymes, signalling intermediates and autophagic processes were evaluated. Female hearts exhibited 51% lower basal glycogen content than males associated with lower AMP-activated-kinase (AMPK) activity (35% decrease in pAMPK:AMPK). With fasting, glycogen accumulated in female hearts linked with decreased particle size and upregulation of Akt and AMPK signalling, activation of glycogen synthase and inactivation of glycogen phosphorylase. Fasting did not alter glycogen content or regulatory proteins in male hearts. Expression of glycogen autophagy marker, starch-binding-protein-domain-1 (STBD1), was 63% lower in female hearts than males and increased by 69% with fasting in females only. Macro-autophagy markers, p62 and LC3BII:I ratio, increased with fasting in male and female hearts. This study identifies glycogen autophagy ('glycophagy') as a potentially important component of the response to cardiac metabolic stress. Glycogen autophagy occurs in association with a marked and selective accumulation of glycogen in the female myocardium. Our findings suggest that sex-specific differences in glycogen handling may have cardiopathologic consequences in various settings, including diabetic cardiomyopathy.


Asunto(s)
Autofagia , Glucógeno/metabolismo , Miocardio/metabolismo , Estrés Fisiológico , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Biomarcadores/metabolismo , Ayuno/metabolismo , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Miocardio/ultraestructura , Tamaño de la Partícula , Proteínas Proto-Oncogénicas c-akt/metabolismo , Caracteres Sexuales , Transducción de Señal
6.
Minerva Cardioangiol ; 61(3): 281-93, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23681131

RESUMEN

The adoption of early revascularization as the preferred strategy in all ST-elevation myocardial infarctions (STEMI) and high risk acute coronary syndromes (ACS) without ST elevation resulted in a considerable reduction in the incidence of post-ACS cardiogenic shock (CS) however the incidence of CS on hospital arrival has not changed. In-hospital and 30 day mortality from CS remains excessively high in facilities with coronary revascularization capabilities. Trials investigating the incremental value of either intra-aortic counter-pulsation (IACP) or advanced MCS did not demonstrate a meaningful mortality reduction. Mortality remains 45-60% and depends on clinical characteristics of the patient, timely and successful revascularization and advanced MCS in suitable candidates. Most CS survivors demonstrate satisfactory functional capacity and quality of life. The authors propose the "Guthrie classification" for post-ACS CS. This classification promotes better characterization of CS patients enrolled in clinical trials and registries. It also allows the clinician to better define the goals and benefits of therapy for the CS subjects. The precise pathophysiology of post-ACS CS remains poorly understood at the biochemical and cellular level. Uncovering and modifying these processes remains key to any fundamental change in post-ACS CS outcomes.


Asunto(s)
Síndrome Coronario Agudo/terapia , Angioplastia Coronaria con Balón , Infarto del Miocardio/terapia , Choque Cardiogénico/prevención & control , Choque Cardiogénico/terapia , Tiempo de Tratamiento , Síndrome Coronario Agudo/mortalidad , Síndrome Coronario Agudo/fisiopatología , Angioplastia Coronaria con Balón/métodos , Cardiotónicos/uso terapéutico , Ensayos Clínicos como Asunto , Dopamina/uso terapéutico , Quimioterapia Combinada , Sistema de Conducción Cardíaco/fisiopatología , Humanos , Incidencia , Infarto del Miocardio/mortalidad , Infarto del Miocardio/fisiopatología , Norepinefrina/uso terapéutico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Respiración Artificial , Prevención Secundaria , Choque Cardiogénico/etiología , Choque Cardiogénico/mortalidad , Choque Cardiogénico/fisiopatología , Tasa de Supervivencia , Resultado del Tratamiento , Estados Unidos/epidemiología , Vasoconstrictores/uso terapéutico
7.
Diabetologia ; 56(3): 675-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23242170

RESUMEN

AIMS/HYPOTHESIS: A key morphological feature of diabetic nephropathy is the accumulation and deposition of glycogen in renal tubular cells, known as Armanni-Ebstein lesions. While this observation has been consistently reported for many years, the molecular basis of these lesions remains unclear. METHODS: Using biochemical and histochemical methods, we measured glycogen concentration, glycogen synthase and glycogen phosphorylase enzyme activities, and mRNA expression and protein levels of glycogenin in kidney lysates from control and transgenic (mRen-2)27 rat models of diabetes that had been treated with and without a new anti-fibrotic agent, FT011. RESULTS: Diabetic nephropathy was associated with increased glycogen content, increased glycogen synthase activity and decreased glycogen phosphorylase activity. Glycogenin, the key protein responsible for initiating the synthesis of each glycogen particle, had very high levels in the diabetic kidney together with increased mRNA expression compared with control kidneys. Treatment with FT011 did not change glycogen synthase or glycogen phosphorylase enzyme activities but prevented both glycogenin mRNA synthesis and accumulation of Armanni-Ebstein lesions in the diabetic kidney. CONCLUSIONS/INTERPRETATION: Armanni-Ebstein lesions found in diabetic nephropathy are due to aberrant glycogenin protein levels and mRNA expression, providing an explanation for the increased glycogen concentration found within the diabetic kidney. FT011 treatment in diabetic rats reduced glycogenin levels and, subsequently, renal glycogen concentration.


Asunto(s)
Antiinflamatorios/uso terapéutico , Ácidos Cafeicos/uso terapéutico , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/enzimología , ortoaminobenzoatos/uso terapéutico , Animales , Nefropatías Diabéticas/metabolismo , Activación Enzimática/efectos de los fármacos , Femenino , Glucosiltransferasas/metabolismo , Glucógeno/metabolismo , Glucógeno Fosforilasa/metabolismo , Glucógeno Sintasa/metabolismo , Glicoproteínas/metabolismo , Ratas , Ratas Transgénicas
8.
Am J Physiol Renal Physiol ; 300(6): F1437-47, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21429972

RESUMEN

Deficiency of the intrinsic lysosomal protein human scavenger receptor class B, member 2 (SCARB2; Limp-2 in mice) causes collapsing focal and segmental glomerular sclerosis (FSGS) and myoclonic epilepsy in humans, but patients with no apparent kidney damage have recently been described. We now demonstrate that these patients can develop tubular proteinuria. To determine the mechanism, mice deficient in Limp-2, the murine homolog of SCARB2, were studied. Most low-molecular-weight proteins filtered by the glomerulus are removed in the proximal convoluted tubule (PCT) by megalin/cubilin-dependent receptor-mediated endocytosis. Expression of megalin and cubilin was unchanged in Limp-2(-/-) mice, however, and the initial uptake of injected Alexa Fluor 555-conjugated bovine serum albumin (Alexa-BSA) was similar to wild-type mice, indicating that megalin/cubilin-dependent, receptor-mediated endocytosis was unaffected. There was a defect in proteolysis of reabsorbed proteins in the Limp-2(-/-) mice, demonstrated by the persistence of Alexa-BSA in the PCT compared with controls. This was associated with the failure of the lysosomal protease cathepsin B to colocalize with Alexa-BSA and endogenous retinol-binding protein in kidneys from Limp-2(-/-) mice. The data suggest that tubular proteinuria in Limp-2(-/-) mice is due to failure of endosomes containing reabsorbed proteins to fuse with lysosomes in the proximal tubule of the kidney. Failure of proteolysis is a novel mechanism for tubular proteinuria.


Asunto(s)
Enfermedades Renales/genética , Riñón/metabolismo , Proteínas de Membrana de los Lisosomas/genética , Proteinuria/genética , Receptores Depuradores/genética , Animales , Técnica del Anticuerpo Fluorescente , Humanos , Enfermedades Renales/metabolismo , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Proteínas de Membrana de los Lisosomas/metabolismo , Lisosomas/metabolismo , Espectrometría de Masas , Ratones , Ratones Noqueados , Proteinuria/metabolismo , Receptores Depuradores/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Parassitologia ; 47(3-4): 353-60, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16866041

RESUMEN

Lewis W. Hackett joined the staff of the International Health Board (IHB) in 1914. He was sent to Brazil in 1916, where his original responsibility was hookworm control, but he was gradually and inevitably drawn into combating other diseases. Hackett had a strong influence on public health in Brazil. In 1922 he instituted grass-roots (local) health units and programs. The next year, he negotiated with the federal government a cooperative yellow fever control program, which was described in the IHB's 1923 annual report as the "new and final campaign against yellow fever" in Brazil. Eleven offices were established in northern Brazil, where it was expected that yellow fever would quickly be eradicated. Just as the new program got underway Hackett was reassigned to Italy, where he remained until the beginning of World War II. Nonetheless, Hackett had done a classic job of developing the IHB program in Brazil, moving carefully but authoritatively from the initial focus on hookworm, to the development of a more comprehensive public health program, and then to the strategic thrust toward yellow fever.


Asunto(s)
Agencias Internacionales/historia , Cooperación Internacional/historia , Fiebre Amarilla/historia , Anquilostomiasis/historia , Anquilostomiasis/terapia , Animales , Brasil/epidemiología , Cultura , Historia del Siglo XX , Humanos , Agencias Internacionales/organización & administración , Malaria/epidemiología , Malaria/historia , Malaria/prevención & control , Control de Mosquitos/historia , Estados Unidos , Fiebre Amarilla/epidemiología , Fiebre Amarilla/prevención & control
12.
J Pediatr Gastroenterol Nutr ; 33(3): 319-25, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11593129

RESUMEN

BACKGROUND: Many children with cystic fibrosis grow poorly and are malnourished. This study was undertaken to determine whether extensive anthropometry could detect early signs of malnutrition in prepubertal children with cystic fibrosis to prevent deficits in height and weight. METHODS: Height, weight, six skin folds (triceps, subscapular, supraspinale, abdominal, front thigh, and medial calf) and five girths (arm relaxed, forearm, chest, thigh, and calf) were measured in a cross-sectional study of children aged 6 to 11 years with cystic fibrosis. RESULTS: The children with cystic fibrosis were shorter and lighter for their age and gender than those in the reference groups. The mean weight and height z scores for the girls with cystic fibrosis were lower than those for the boys, significantly so for z weight ( P < 0.05). Although, the mean percent ideal body weight value of 98.6% suggested that the children with cystic fibrosis were adequately nourished, most of the measures of muscularity and adiposity of the children with cystic fibrosis were significantly lower than those of the reference group ( P < 0.05). The z scores of the anthropometric measures revealed that the deficit in muscularity of the children with cystic fibrosis was relatively much greater than the deficit in adiposity. CONCLUSIONS: The percent ideal body weight index does not seem to be an adequate measure of nutritional status in children with cystic fibrosis. Anthropometric assessments should include skin-fold and circumference measurements of numerous sites on the upper and lower body, the trunk, and the limbs to detect deterioration in nutritional status early. Early detection of deficits in nutritional status may result in the adverse effects of malnutrition on height and weight, and possibly clinical status, being prevented.


Asunto(s)
Trastornos de la Nutrición del Niño/diagnóstico , Trastornos de la Nutrición del Niño/etiología , Fibrosis Quística/complicaciones , Antropometría , Estatura , Peso Corporal , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Valores de Referencia , Pruebas de Función Respiratoria , Factores Sexuales
13.
FEBS Lett ; 500(3): 163-8, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11445078

RESUMEN

The AMP-activated protein kinase (AMPK) is a heterotrimeric protein composed of a catalytic alpha subunit and two regulatory subunits, beta and gamma. The gamma subunit is essential for enzyme activity by virtue of its binding to the C-terminus of the alpha subunit and appears to play some role in the determination of AMP sensitivity. We demonstrate that a gamma1R70Q mutation causes a marked increase in AMPK activity and renders it largely AMP-independent. This activation is associated with increased phosphorylation of the alpha subunit activation loop T172. These in vitro characteristics of AMPK are also reflected in increased intracellular phosphorylation of one of its major substrates, acetyl-CoA carboxylase. These data illustrate the importance of the gamma1 subunit in the regulation of AMPK and its modulation by AMP.


Asunto(s)
Proteínas Portadoras , Mutagénesis Sitio-Dirigida , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Subunidades de Proteína , Proteínas de Saccharomyces cerevisiae , Proteínas Quinasas Activadas por AMP , Sustitución de Aminoácidos , Animales , Células COS , Línea Celular , Activación Enzimática/genética , Expresión Génica , Humanos , Isoenzimas/genética , Fosforilación , Estructura Terciaria de Proteína/genética , Alineación de Secuencia , Relación Estructura-Actividad , Factores de Transcripción/genética , Transfección , Levaduras
14.
J Biol Chem ; 276(21): 17625-8, 2001 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-11292821

RESUMEN

Endothelial nitric-oxide synthase (eNOS) is an important regulatory enzyme in the cardiovascular system catalyzing the production of NO from arginine. Multiple protein kinases including Akt/PKB, cAMP-dependent protein kinase (PKA), and the AMP-activated protein kinase (AMPK) activate eNOS by phosphorylating Ser-1177 in response to various stimuli. During VEGF signaling in endothelial cells, there is a transient increase in Ser-1177 phosphorylation coupled with a decrease in Thr-495 phosphorylation that reverses over 10 min. PKC signaling in endothelial cells inhibits eNOS activity by phosphorylating Thr-495 and dephosphorylating Ser-1177 whereas PKA signaling acts in reverse by increasing phosphorylation of Ser-1177 and dephosphorylation of Thr-495 to activate eNOS. Both phosphatases PP1 and PP2A are associated with eNOS. PP1 is responsible for dephosphorylation of Thr-495 based on its specificity for this site in both eNOS and the corresponding synthetic phosphopeptide whereas PP2A is responsible for dephosphorylation of Ser-1177. Treatment of endothelial cells with calyculin selectively blocks PKA-mediated dephosphorylation of Thr-495 whereas okadaic acid selectively blocks PKC-mediated dephosphorylation of Ser-1177. These results show that regulation of eNOS activity involves coordinated signaling through Ser-1177 and Thr-495 by multiple protein kinases and phosphatases.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Endotelio Vascular/metabolismo , Óxido Nítrico Sintasa/metabolismo , Proteína Quinasa C/metabolismo , Animales , Bovinos , Células Cultivadas , Óxido Nítrico Sintasa de Tipo III , Fosforilación , Transducción de Señal
15.
Biochem J ; 354(Pt 2): 275-83, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11171104

RESUMEN

The AMP-activated protein kinase (AMPK) is a ubiquitous mammalian protein kinase important in the adaptation of cells to metabolic stress. The enzyme is a heterotrimer, consisting of a catalytic alpha subunit and regulatory beta and gamma subunits, each of which is a member of a larger isoform family. The enzyme is allosterically regulated by AMP and by phosphorylation of the alpha subunit. The beta subunit is post-translationally modified by myristoylation and multi-site phosphorylation. In the present study, we have examined the impact of post-translational modification of the beta-1 subunit on enzyme activity, heterotrimer assembly and subcellular localization, using site-directed mutagenesis and expression of subunits in mammalian cells. Removal of the myristoylation site (G2A mutant) results in a 4-fold activation of the enzyme and relocalization of the beta subunit from a particulate extranuclear distribution to a more homogenous cell distribution. Mutation of the serine-108 phosphorylation site to alanine is associated with enzyme inhibition, but no change in cell localization. In contrast, the phosphorylation site mutations, SS24, 25AA and S182A, while having no effects on enzyme activity, are associated with nuclear redistribution of the subunit. Taken together, these results indicate that both myristoylation and phosphorylation of the beta subunit of AMPK modulate enzyme activity and subunit cellular localization, increasing the complexity of AMPK regulation.


Asunto(s)
Complejos Multienzimáticos/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Quinasas Activadas por AMP , Animales , Células COS , Dominio Catalítico/genética , Proteínas Fluorescentes Verdes , Humanos , Cinética , Proteínas Luminiscentes/metabolismo , Complejos Multienzimáticos/química , Complejos Multienzimáticos/genética , Mutagénesis Sitio-Dirigida , Ácido Mirístico/metabolismo , Fosforilación , Conformación Proteica , Pliegue de Proteína , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Subunidades de Proteína , Proteínas Recombinantes de Fusión/metabolismo , Relación Estructura-Actividad
16.
Soc Secur Bull ; 64(1): 84-114, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12428519

RESUMEN

The Supplemental Security Income (SSI) and Aid to Families with Dependent Children (AFDC) programs serve populations with similar characteristics. SSI serves adults and children with disabilities who are in low-income families, and AFDC serves low-income families with children. Because of that overlap, policy changes in one program can affect the other. In 1996, Congress enacted the Personal Responsibility and Work Opportunity Reconciliation Act, which transformed AFDC into the Temporary Assistance for Needy Families (TANF) program. Many people have expected that implementing that welfare reform legislation would eventually increase SSI participation, for two reasons. First, TANF includes new work requirements and time limits that induce more AFDC/TANF recipients with disabilities to obtain SSI benefits. Second, the change in the funding mechanism--from open-ended funding on a matching basis for AFDC to cash assistance block grants for TANF--gives states a stronger incentive to shift welfare recipients to SSI. This article examines the interaction between the SSI and AFDC programs in the prereform period (1990 to 1996) and discusses the potential implications of welfare reform on that interaction. Using matched data from the Survey of Income and Program Participation and Social Security Administration (SSA) records, our analysis focuses on how the interaction of those programs affects young women (aged 18 to 40) and children (aged 0 to 17). We find a very strong link between AFDC and SSI for young women and children. Significant portions of young female and child SSI beneficiaries in the 1990-1993 period were in AFDC families or had received AFDC in the past. In addition, a substantial share of young women and children who received AFDC during that period eventually entered SSI. Because the SSI program is now serving a much larger population of families with young women and children than in the past, SSA might need to develop policies to better serve that group. The findings also suggest that the prereform period is a poor baseline against which to measure the impact of TANF, primarily because of the instability in programs and policies.


Asunto(s)
Ayuda a Familias con Hijos Dependientes/estadística & datos numéricos , Política Pública , Seguridad Social/estadística & datos numéricos , Adolescente , Adulto , Ayuda a Familias con Hijos Dependientes/organización & administración , Niño , Preescolar , Toma de Decisiones , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Modelos Econométricos , Análisis Multivariante , Modelos de Riesgos Proporcionales , Seguridad Social/organización & administración , Estados Unidos
18.
J Am Diet Assoc ; 100(12): 1494-500, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11138442

RESUMEN

OBJECTIVE: To describe the development and validation of questionnaires designed to assess nutrition and pancreatic enzyme replacement therapy knowledge and cystic fibrosis self-management skills, and the results obtained when the questionnaires were used. DESIGN: A cross-sectional study using validated questionnaires to interview the respondents. The outcome measures were scores for knowledge, appropriate and inappropriate self-management, and Socioeconomic Index. SUBJECTS: Forty-two children with cystic fibrosis aged 6 to 11 years and 55 caregivers of 2 to 11-year-old patients of the Princess Margaret Hospital Cystic Fibrosis Clinic, Perth, Australia. STATISTICAL ANALYSES: Descriptive statistics and correlations between scores were used for statistical analyses. Associations between knowledge scores were examined using Pearson's correlation coefficient. Spearman's rank correlation was used to examine the associations between knowledge and self-management scores and socioeconomic index. RESULTS: Children's and caregivers' mean knowledge scores were 63% and 85%, respectively. Mean appropriate and inappropriate self-management scores for children were 55% and 21%, respectively, and for the caregivers were 74% and 32%, respectively. There was a statistically significant (P < .05) positive association between caregivers' and children's knowledge (r = 0.32), and children's knowledge and appropriate self-management scores (r = 0.41); and a statistically significant negative association between caregivers' knowledge and inappropriate self-management scores (r = -0.35); and no statistically significant associations between Socioeconomic Index and children's and caregivers' knowledge and self-management scores. APPLICATIONS: This study identified areas in which the nutrition knowledge of children with cystic fibrosis and their caregivers needs to be enhanced to increase the likelihood that optimum dietary and pancreatic enzyme therapy is achieved. The questionnaires that were developed for the study could be refined and used in the clinical setting to identify knowledge and self-management deficits. Alternatively, the questionnaires could become valuable research tools for assessing the type of intervention required and in planning and evaluating programs.


Asunto(s)
Cuidadores , Fibrosis Quística , Conocimientos, Actitudes y Práctica en Salud , Ciencias de la Nutrición , Páncreas/enzimología , Autocuidado , Adulto , Cuidadores/educación , Cuidadores/estadística & datos numéricos , Niño , Preescolar , Estudios Transversales , Fibrosis Quística/psicología , Fibrosis Quística/terapia , Grasas de la Dieta/administración & dosificación , Femenino , Humanos , Entrevistas como Asunto , Masculino , Ciencias de la Nutrición/educación , Reproducibilidad de los Resultados , Factores Socioeconómicos , Estadística como Asunto , Encuestas y Cuestionarios
19.
Am J Med Sci ; 320(6): 394-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11149552

RESUMEN

BACKGROUND: The 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors lovastatin and simvastatin have been associated with rhabdomyolysis in cardiac transplant recipients. Herein, we report a case of a 52-year-old male recipient of a cardiac transplant who developed rhabdomyolysis and acute renal failure caused by simvastatin precipitated by multiple drug interactions. METHODS: The patient had a history of cardiac transplantation (5 years before) and presented with a 2-day history of dark urine preceded by 2 weeks of diffuse myalgias. He had been maintained on cyclosporine throughout the entire post-transplant period. Simvastatin was added and pravastatin was discontinued 2 months before admission. Two weeks before the onset of muscle symptoms, digoxin and verapamil were started for new-onset atrial fibrillation. Creatinine phosphokinase levels peaked at 950,000 IU with serum creatinine of 3.3 mg/dL (baseline, 1.8 mg/dL). RESULTS: Review of the medication history indicates a temporal association between the addition of 3 drugs (simvastatin, verapamil, and digoxin) to the medication regimen already containing cyclosporine and the episode of rhabdomyolysis. All of these drugs are cytochrome P450 3A4 and/or P-glycoprotein substrates that are known from previous pharmacokinetic studies to individually produce substantial increases in levels of simvastatin. CONCLUSION: We believe this case illustrates that avoiding the use of drugs that are cytochrome P450 3A4 and/or P-glycoprotein substrates reduces the risk of rhabdomyolysis caused by 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Antiarrítmicos/efectos adversos , Ciclosporina/efectos adversos , Digoxina/efectos adversos , Inhibidores Enzimáticos/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Inmunosupresores/efectos adversos , Rabdomiólisis/inducido químicamente , Simvastatina/efectos adversos , Verapamilo/efectos adversos , Antiarrítmicos/administración & dosificación , Ciclosporina/administración & dosificación , Digoxina/administración & dosificación , Interacciones Farmacológicas , Inhibidores Enzimáticos/administración & dosificación , Trasplante de Corazón , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana Edad , Simvastatina/administración & dosificación , Verapamilo/administración & dosificación
20.
Parassitologia ; 42(1-2): 127-34, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11234323

RESUMEN

The Rockefeller Foundation's support of malaria control and public health in Italy over three decades, the 1920s, 1930s and 1940s, was one of the foundation's most successful collaborations in its history. Nearly one-sixth of the funds the Rockefeller Foundation allocated for malaria programs was spent in Italy in those years. Outstanding research, a new and important institution, and decided improvements in public health were historically-significant results. The three most important episodes of this American-Italian relationship were the operations of the Stazione Sperimentale per la Lotta Antimalarica, the founding of the Istituto Superiore di Sanità, and the campaign to eradicate mosquitoes in Sardinia. In each of these episodes there was a tension between the international aspects and national aspects of the partnership that to some degree limited its success.


Asunto(s)
Fundaciones/historia , Cooperación Internacional/historia , Malaria/historia , Salud Pública/historia , Historia del Siglo XX , Humanos , Italia
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