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1.
Diabet Med ; 31(7): 839-46, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24606323

RESUMEN

AIMS: To develop glycaemic goal individualization algorithms and assess potential impact on a healthcare system and different segments of the population with diabetes. METHODS: A cross-sectional observational study of patients with diabetes in a primary care network age > 18 years with an HbA1c measured between 1 January and 31 December 2011. We applied diabetes guidelines to create targeted algorithms 1 and 2, which assigned HbA1c goals based on age, duration of diabetes (< 15 years or < 10 years), diabetes complications and Charlson co-morbidity score (< 6 or < 4) [targeted algorithm 2 was designed to assign more patients a goal < 64 mmol/mol (8.0%) than targeted algorithm 1]. Each patient's HbA1c was compared with these targeted goals and to the 'standard' goal < 53 mmol/mol (7.0%). Agreement was tested using McNemar's test. RESULTS: Overall, 55.7% of 12 199 patients would be considered controlled under the 'standard' approach, 61.2% under targeted algorithm 1 and 67.5% under targeted algorithm 2. Targeted algorithm 1 reclassified 1213 (23.6%) patients considered uncontrolled under the standard approach to controlled, P < 0.001. Targeted algorithm 2 reclassified 1844 (35.2%) patients, P < 0.001. Compared with those controlled under the standard goal, there was no significant difference in the proportion of those controlled using targeted goals who had Medicaid, had less than a high school diploma or received primary care in a federally qualified health centre. CONCLUSIONS: Two automated targeted algorithms would reclassify one quarter to one third of patients from uncontrolled to controlled within a primary care network without differentially affecting vulnerable patient subgroups.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina Glucada/metabolismo , Medicina de Precisión , Anciano , Algoritmos , Comorbilidad , Estudios Transversales , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Escolaridad , Femenino , Índice Glucémico , Humanos , Masculino , Medicaid , Persona de Mediana Edad , Medicina de Precisión/tendencias , Atención Primaria de Salud , Estados Unidos/epidemiología
2.
Diabet Med ; 30(2): e56-62, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23126686

RESUMEN

AIM: To examine the association of in-hospital diabetes regimen intensification with subsequent 30-day risk for unplanned readmission/emergency department admission. METHODS: We retrospectively studied 1949 adults with Type 2 diabetes receiving primary care within an academic health network admitted to the hospital between January 2007 and December 2009. Glucose therapy intensification was defined as new start of insulin or oral hypoglycaemic agents, or addition of prandial insulin or insulin mixtures. The association of glucose therapy intensification with subsequent 30-day risk for unplanned readmission/emergency department admission was examined, with focus on medicine service patients with poorly controlled glycaemia (baseline HbA(1c) ≥ 64 mmol/mol). RESULTS: One in six patients (324/1949, 17%) had early readmission/emergency department admission. Compared with patients without early readmission, readmitted patients were more often male (58 vs. 52%, P = 0.03), had higher Charlson co-morbidity score [mean (sd) 3.0 (2.0) vs. 2.8 (1.8), P = 0.02], longer length of stay [5 (4.4) vs. 3.9 (3.3) days, P < 0.01] and were more often discharged home with nursing services (38 vs. 32%, P = 0.03). Overall, glucose therapy intensification was not associated with early hospital readmission/emergency department admission (odds ratio 0.94, 95% CI 0.64-1.37, P = 0.74). However, among medicine service patients with baseline HbA(1c) ≥ 64 mmol/mol (8%), glucose therapy intensification was associated with a significantly decreased early readmission risk (adjusted odds ratio 0.33, 95% CI 0.12-0.88, P = 0.03) and lower post-discharge HbA(1c) {mean decrease (sd): 20 (26) mmol/mol [1.8 (2.4)%] vs. 7 (15) mmol/mol [0.6 (1.4)%], P < 0.01}. CONCLUSIONS: Diabetes medical regimen intensification during hospitalization was not associated with early readmission. Among patients with elevated HbA(1c) , glucose therapy intensification was associated with a decreased 30-day readmission/emergency department admission risk and lower outpatient HbA(1c) levels. Our findings support the safety and durable impact of diabetes regimen optimization during hospital admission.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Servicio de Urgencia en Hospital/estadística & datos numéricos , Hemoglobina Glucada/efectos de los fármacos , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Readmisión del Paciente/estadística & datos numéricos , Anciano , Glucemia/metabolismo , Análisis Costo-Beneficio , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Esquema de Medicación , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Massachusetts/epidemiología , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento
3.
Diabetes Obes Metab ; 13(7): 669-72, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21457428

RESUMEN

Canagliflozin, a potent, selective sodium glucose co-transporter 2 inhibitor in development for treatment of type 2 diabetes, lowers plasma glucose (PG) by lowering the renal threshold for glucose (RT(G) ) and increasing urinary glucose excretion (UGE). An ascending single oral-dose phase 1 study investigated safety, tolerability and pharmacodynamics of canagliflozin in healthy men (N = 63) randomized to receive canagliflozin (n = 48) or placebo (n = 15). Canagliflozin (10, 30, 100, 200, 400, 600 or 800 mg q.d. or 400 mg b.i.d.) was administered to eight cohorts (six subjects/cohort: canagliflozin; two subjects/cohort: placebo). Dose dependently, canagliflozin decreased calculated 24-h mean RT(G) with maximal reduction to approximately 60 mg/dl, and increased mean 24-h UGE. At doses >200 mg administered before breakfast, canagliflozin reduced postprandial PG and serum insulin excursions at that meal. Canagliflozin was generally well tolerated; most adverse events were mild and no hypoglycaemia was reported. These results support further study of canagliflozin.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucósidos/farmacología , Glucosuria/metabolismo , Hipoglucemiantes/uso terapéutico , Insulina/metabolismo , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Tiofenos/farmacología , Adolescente , Adulto , Canagliflozina , Diabetes Mellitus Tipo 2/metabolismo , Relación Dosis-Respuesta a Droga , Glucósidos/uso terapéutico , Glucosuria/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Tiofenos/uso terapéutico , Adulto Joven
4.
J Cogn Psychother ; 24(4): 329-343, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23667294

RESUMEN

Depression is one of the most common psychological problems among individuals diabetes, and it is associated with worse treatment adherence and clinical outcomes. As part of a program of treatment research aimed at integrating interventions for depression and treatment nonadherence, five depressed patients with suboptimally controlled type 2 diabetes were treated with 10-12 sessions of individual cognitive behavioral therapy for adherence and depression (CBT-AD) in a case-series design. The intervention was delivered in a hospital setting by a collaborative team consisting of a psychologist, a nurse educator, and a dietitian. Post-treatment, all participants demonstrated a decrease in depression severity and demonstrated improvements in diabetes self-care. Four of the five demonstrated improved glycemic control. These preliminary results provide evidence for the acceptability, feasibility, and potential utility of CBT-AD for patients with type 2 diabetes and depression.

5.
Diabet Med ; 25(9): 1102-7, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19183315

RESUMEN

AIMS: To examine prospectively the association of depression symptoms with subsequent self-care and medication adherence in patients with Type 2 diabetes mellitus. METHODS: Two hundred and eight primary care patients with Type 2 diabetes completed the Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS) and the Summary of Diabetes Self-Care Activities (SDSCA) at baseline and at follow-up, an average of 9 months later. They also self-reported medication adherence at baseline and at a follow-up. RESULTS: Baseline HANDS scores ranged from 0 to 27, with a mean score of 5.15 +/- 4.99. In separate linear regression models that adjusted for baseline self-care, patients with higher levels of depressive symptoms at baseline reported significantly lower adherence to general diet recommendations and specific recommendations for consumption of fruits and vegetables and spacing of carbohydrates; less exercise; and poorer foot care at follow-up (beta ranging from -0.12 to -0.23; P < 0.05). Similarly, each one-point increase in baseline HANDS score was associated with a 1.08-fold increase in the odds of non-adherence to prescribed medication at follow-up (95% confidence interval 1.001, 1.158, P = 0.047). Increases in depression scores over time also predicted poorer adherence to aspects of diet and exercise. CONCLUSIONS: Depressive symptoms predict subsequent non-adherence to important aspects of self-care in patients with Type 2 diabetes, even after controlling for baseline self-care. Although the relationship between symptoms of depression and poorer diabetes self-care is consistent, it is not large, and interventions may need to address depression and self-care skills simultaneously in order to maximize effects on diabetes outcomes.


Asunto(s)
Trastorno Depresivo/etiología , Diabetes Mellitus Tipo 2/psicología , Cooperación del Paciente/psicología , Autocuidado/psicología , Anciano , Diabetes Mellitus Tipo 2/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estrés Psicológico/etiología
6.
Mol Cell Biol ; 11(6): 3191-202, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1674818

RESUMEN

The epidermal growth factor receptor (EGFR) and gp185erbB-2 are closely related tyrosine kinases. Despite extensive sequence and structural homology, these two receptors display quantitative and qualitative differences in their ability to couple with mitogenic signalling pathways. By using chimeric molecules between EGFR and erbB-2, we found that the determinants responsible for the specificity of mitogenic signal transduction are located in the amino-terminal half of the tyrosine kinase domain of either receptor. In the EGFR, mutational analysis within this subdomain revealed that deletion of residues 660 to 667 impaired receptor mitogenic activity without affecting its tyrosine kinase properties. This sequence is therefore likely to contribute to the specificity of substrate recognition by the EGFR kinase.


Asunto(s)
Receptores ErbB/fisiología , Proteínas Tirosina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Transducción de Señal , Secuencia de Aminoácidos , Animales , División Celular , Línea Celular , Membrana Celular/fisiología , Receptores ErbB/genética , Variación Genética , Vectores Genéticos , Ratones , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Proto-Oncogénicas/genética , Receptor ErbB-2 , Transfección
7.
Oncogene ; 7(7): 1339-46, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1352397

RESUMEN

Autophosphorylation of gp185erbB-2 in vivo is confined to its carboxy terminus and is required for optimal erbB-2 transforming activity under conditions of receptor overexpression. It remains unresolved, however, to what extent autophosphorylation regulates erbB-2 mitogenic signaling in normal cells, nor is the biochemical basis for such a regulatory function known. To address these issues, we utilized a chimeric molecule encompassing the extracellular domain of the epidermal growth factor (EGF) receptor (EGFR) fused to the transmembrane and intracellular domains of the erbB-2 product. In this EGFR/erbB-2 chimera, erbB-2 kinase activity is regulated by EGF binding. An EGFR/erbB-2 mutant bearing multiple Tyr----Phe substitutions at erbB-2 autophosphorylation sites (EGFR/erbB-2 5P) displayed markedly reduced phosphotyrosine content following EGF stimulation in comparison with the non-mutated chimera. When expressed in NR6 cells, the EGFR/erbB-2 5P mutant was unable to deliver a sizeable mitogenic signal when activated by EGF at physiological levels. In intact cells, the 5P mutant was still able to stimulate phosphorylation of the gamma isozyme of phospholipase C (PLC-gamma), a prototype erbB-2 substrate, although with a delayed time course, indicating that the 5P mutation decreased the affinity of the erbB-2 kinase for this substrate. This conclusion was further supported by the inability of the 5P mutant to associate with PLC-gamma in co-immunoprecipitation experiments. We infer that a major role of autophosphorylation is to increase the affinity of the erbB-2 kinase for its cellular substrates, so that, under physiological conditions, autophosphorylation is absolutely required for erbB-2 mitogenic signaling.


Asunto(s)
Sustancias de Crecimiento/metabolismo , Sustancias de Crecimiento/fisiología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/fisiología , Secuencia de Aminoácidos , Línea Celular , Receptores ErbB/metabolismo , Datos de Secuencia Molecular , Mutación , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Receptor ErbB-2 , Proteínas Recombinantes de Fusión , Transducción de Señal
8.
J Am Coll Cardiol ; 37(7): 1775-80, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11401110

RESUMEN

OBJECTIVES: This is a randomized controlled study of anemic patients with severe congestive heart failure (CHF) to assess the effect of correction of the anemia on cardiac and renal function and hospitalization. BACKGROUND: Although mild anemia occurs frequently in patients with CHF, there is very little information about the effect of correcting it with erythropoietin (EPO) and intravenous iron. METHODS: Thirty-two patients with moderate to severe CHF (New York Heart Association [NYHA] class III to IV) who had a left ventricular ejection fraction (LVEF) of < or =40% despite maximally tolerated doses of CHF medications and whose hemoglobin (Hb) levels were persistently between 10.0 and 11.5 g% were randomized into two groups. Group A (16 patients) received subcutaneous EPO and IV iron to increase the level of Hb to at least 12.5 g%. In Group B (16 patients) the anemia was not treated. The doses of all the CHF medications were maintained at the maximally tolerated levels except for oral and intravenous (IV) furosemide, whose doses were increased or decreased according to the clinical need. RESULTS: Over a mean of 8.2+/-2.6 months, four patients in Group B and none in Group A died of CHF-related illnesses. The mean NYHA class improved by 42.1% in A and worsened by 11.4% in B. The LVEF increased by 5.5% in A and decreased by 5.4% in B. The serum creatinine did not change in A and increased by 28.6% in B. The need for oral and IV furosemide decreased by 51.3% and 91.3% respectively in A and increased by 28.5% and 28.0% respectively in B. The number of days spent in hospital compared with the same period of time before entering the study decreased by 79.0% in A and increased by 57.6% in B. CONCLUSIONS: When anemia in CHF is treated with EPO and IV iron, a marked improvement in cardiac and patient function is seen, associated with less hospitalization and renal impairment and less need for diuretics.


Asunto(s)
Anemia/complicaciones , Anemia/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/tratamiento farmacológico , Hierro/administración & dosificación , Anciano , Femenino , Humanos , Inyecciones Intravenosas , Inyecciones Subcutáneas , Masculino , Estudios Prospectivos , Índice de Severidad de la Enfermedad
9.
J Am Coll Cardiol ; 35(7): 1737-44, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10841219

RESUMEN

OBJECTIVES: This study evaluated the prevalence and severity of anemia in patients with congestive heart failure (CHF) and the effect of its correction on cardiac and renal function and hospitalization. BACKGROUND: The prevalence and significance of mild anemia in patients with CHF is uncertain, and the role of erythropoietin with intravenous iron supplementation in treating this anemia is unknown. METHODS: In a retrospective study, the records of the 142 patients in our CHF clinic were reviewed to find the prevalence and severity of anemia (hemoglobin [Hb] <12 g). In an intervention study, 26 of these patients, despite maximally tolerated therapy of CHF for at least six months, still had had severe CHF and were also anemic. They were treated with subcutaneous erythropoietin and intravenous iron sufficient to increase the Hb to 12 g%. The doses of the CHF medications, except for diuretics, were not changed during the intervention period. RESULTS: The prevalence of anemia in the 142 patients increased with the severity of CHF, reaching 79.1% in those with New York Heart Association class IV. In the intervention study, the anemia of the 26 patients was treated for a mean of 7.2 +/- 5.5 months. The mean Hb level and mean left ventricular ejection fraction increased significantly. The mean number of hospitalizations fell by 91.9% compared with a similar period before the study. The New York Heart Association class fell significantly, as did the doses of oral and intravenous furosemide. The rate of fall of the glomerular filtration rate slowed with the treatment. CONCLUSIONS: Anemia is very common in CHF and its successful treatment is associated with a significant improvement in cardiac function, functional class, renal function and in a marked fall in the need for diuretics and hospitalization.


Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Insuficiencia Cardíaca/complicaciones , Hierro/administración & dosificación , Anciano , Anemia Ferropénica/epidemiología , Anemia Ferropénica/etiología , Anemia Ferropénica/fisiopatología , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Tasa de Filtración Glomerular/fisiología , Insuficiencia Cardíaca/fisiopatología , Hospitalización/estadística & datos numéricos , Humanos , Inyecciones Intravenosas , Inyecciones Subcutáneas , Masculino , Prevalencia , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/fisiología
10.
Genetics ; 118(4): 637-48, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3366366

RESUMEN

The length of the flagella of Chlamydomonas reinhardtii cells is tightly regulated; both short-flagella and long-flagella mutants have been described. This report characterizes ten long-flagella mutants, including five newly isolated mutants, to determine the number of different loci conferring this phenotype, and to study interactions of mutants at different loci. The mutants, each of which was recessive in heterozygous diploids with wild type, fall into three unlinked complementation groups. One of these defines a new gene, lf3, which maps near the centromere of linkage group I. The flagellar length distributions in populations of each mutant were broad, with the longest flagella measuring four times the length of the longest flagella seen on wild-type cells. Each of the ten mutants had defective flagellar regrowth after amputation. Some of the mutants showed no regrowth within the time required for wild-type cells to regenerate flagella completely. Other mutants had subpopulations with rapid regeneration kinetics, and subpopulations with no observable regeneration. The mutants were each crossed to wild type to form temporary quadriflagellate, dikaryon cells; in each case the long flagella were rapidly shortened in the presence of the wild-type cytoplasm, demonstrating that the mutants were recessive, and that length control could be exerted on already assembled flagella.


Asunto(s)
Chlamydomonas/genética , Flagelos/ultraestructura , Chlamydomonas/ultraestructura , Cruzamientos Genéticos , Genes Recesivos , Prueba de Complementación Genética , Ligamiento Genético , Mutación , Fenotipo
11.
J Am Geriatr Soc ; 33(6): 383-91, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3998347

RESUMEN

The role of physicians in the long-term management of patients with the primary diagnosis of progressive dementia was investigated by surveying the opinions of 57 physicians and 47 family members. Respondents were asked to evaluate the difficulty and helpfulness of various activities physicians perform in the diagnosis, treatment, and management of patients with dementia. Both physicians and families rated the diagnostic services provided by physicians very highly. Although families found physicians' explanations of the diagnosis and prognosis extremely helpful, physicians reported this as an area of difficulty. Physicians and families expressed considerable frustration with the limited medical treatments and interventions for the relief of symptoms associated with dementia. Despite the acknowledged sensitivity of physicians to the social-psychological consequences of dementia, physicians were found to be least helpful in addressing these issues, either directly or through referral to allied health and social services. This study outlines areas of physician education that need improvement and calls for development of an interdisciplinary network of services for the biopsychosocial management of dementia.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Demencia/terapia , Familia , Rol del Médico , Rol , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/terapia , Enfermedad Crónica , Consejo , Demencia/diagnóstico , Análisis Factorial , Humanos , Relaciones Profesional-Familia , Pronóstico , Encuestas y Cuestionarios
12.
J Clin Pharmacol ; 29(7): 650-4, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2760258

RESUMEN

The purpose of the research was to ascertain the comparative differences of quinolone antibiotics on theophylline pharmacokinetics. Eight healthy male volunteers were randomly assigned to four treatments. Each was administered norfloxacin (NOR) 800 mg/d, ciprofloxacin (C) 1 g/d, nalidixic acid (NAL) 2 g/d and placebo (P) for 7 days. On the seventh day of each treatment, theophylline (5 mg/kg) iv was administered. The elimination half-life (T 1/2), total body clearance (CL) and volume of distribution at steady state (Vss) of theophylline were calculated using model-independent methods. ANOVA for repeated measures was used for data comparisons. The mean (SD) theophylline results were: CL l/kg/h--NOR .038 (.006), C .033 (.006), NAL .045 (.008), P .044 (.007); T 1/2 h--NOR 9.2 (1.8), C 10.6 (1.8), NAL 8.3 (1.8), P 7.5 (1.4). Theophylline Vss differences by treatment were not significant. NOR and C significantly decreased theophylline's clearance and the clearance change can be of clinical significance.


Asunto(s)
Ciprofloxacina/farmacología , Ácido Nalidíxico/farmacología , Norfloxacino/farmacología , Teofilina/farmacocinética , Adulto , Ciprofloxacina/sangre , Semivida , Humanos , Masculino , Tasa de Depuración Metabólica , Ácido Nalidíxico/sangre , Norfloxacino/sangre , Distribución Aleatoria , Teofilina/administración & dosificación
13.
J Clin Pharmacol ; 41(9): 943-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11549098

RESUMEN

Ezetimibe is a novel selective inhibitor of intestinal cholesterol absorption, which has been shown to significantly decrease low-density lipoprotein cholesterol (LDL-C). In this article, the relationship between plasma ezetimibe concentrations and lowering of LDL-C is determined using Emax and regression models. Data from two phase II double-blind placebo-controlled studies (n = 232 and 177) were used in which daily doses of ezetimibe ranging from 0.25 to 10 mg were administered for 12 weeks. Ezetimibe concentrations correlated significantly with percentage change in LDL-C from baseline (%LDL-C). Reductions in %LDL-C of 10%, 15%, and 20% were achieved with concentrations in the ranges 0 to 2, 2 to 15, and > 15 ng/ml, respectively, as compared with placebo. To achieve > 15% reduction in LDL-C, patients need to maintain trough concentrations > 15 ng/ml, taking plasma concentrations as a surrogate for concentrations at the enterocyte. Based on the doses administered, the 10 mg dose had the highest likelihood of sustaining such concentrations, confirming that a daily 10 mg dose of ezetimibe is an optimal therapeutic dose in the treatment of hypercholesterolemia.


Asunto(s)
Anticolesterolemiantes/sangre , Anticolesterolemiantes/uso terapéutico , Azetidinas/sangre , Azetidinas/uso terapéutico , LDL-Colesterol/sangre , Hipercolesterolemia/tratamiento farmacológico , Adolescente , Adulto , Anciano , Algoritmos , Anticolesterolemiantes/efectos adversos , Azetidinas/efectos adversos , Cromatografía Liquida , Relación Dosis-Respuesta a Droga , Ezetimiba , Femenino , Humanos , Hipercolesterolemia/sangre , Modelos Lineales , Masculino , Espectrometría de Masas , Persona de Mediana Edad
14.
Clin Ther ; 23(6): 871-85, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11440287

RESUMEN

BACKGROUND: Ezetimibe, a selective inhibitor of intestinal cholesterol absorption, is in clinical development for the treatment of hypercholesterolemia. It is rapidly absorbed and glucuronidated in the intestine. The parent compound and its conjugated metabolite undergo enterohepatic recirculation, resulting in multiple peaks in the plasma concentration-time profile. OBJECTIVE: The purpose of this study was to develop a population pharmacokinetic (PPK) model for ezetimibe that incorporates enterohepatic recirculation. METHODS: A population compartment model incorporating input from the gallbladder, consistent with food intake, was developed to account for enterohepatic recirculation. The amount recycled was allowed to vary within a subject and between subjects, accommodating variability in bile secretion. The data used consisted of 90 profiles from healthy subjects who received single or multiple doses of ezetimibe 10 or 20 mg. Modeling was carried out using a nonlinear mixed-effect function in the S-PLUS statistical program. RESULTS: The amount of ezetimibe recycled into the central compartment was estimated to be approximately 17% to 20% of the total amount absorbed, independent of the volume of distribution. The intersubject coefficient of variation was 46% to 80% in the absorption rate constant, 27% in the distribution phase, and approximately 50% in the volume of distribution. CONCLUSIONS: PPK models adapted for enterohepatic recirculation allowed a formal assessment of the magnitude and frequency of the enterohepatic recirculation process, and the associated intersubject and intrasubject variability in healthy subjects. The PPK approach also helped to assess the correlation between the observed maximum or minimum (24 hours postdose) concentration with the model-based area under the curve, confirming the appropriateness of the former measures as a surrogate of drug exposure for a possible correlation with pharmacodynamics.


Asunto(s)
Anticolesterolemiantes/farmacocinética , Azetidinas/farmacocinética , Circulación Enterohepática , Adulto , Algoritmos , Anticolesterolemiantes/sangre , Área Bajo la Curva , Azetidinas/sangre , Ezetimiba , Femenino , Semivida , Humanos , Masculino , Modelos Biológicos
15.
J Dent Res ; 75(8): 1572-7, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8906125

RESUMEN

To define the role of dental plaque fructans and the enzymes involved in their metabolism in the initiation and progression of dental caries, we constructed otherwise-isogenic mutants of Streptococcus mutans defective in the ability to synthesize fructans, to degrade fructans, or to do both. The cariogenic potential of these organisms was evaluated in a specific-pathogen-free rat model in which the feeding patterns of the animals were controlled by means of a König-Hofer programed feeder. Specifically, rats were infected with wild-type S. mutans UA159 or derivatives of this strain which contained an insertionally-inactivated fructanase (fruA) gene, fructosyltransferase (ftf) gene, or which had both genes inactivated. The animals were fed 17 meals per day of Diet 2000 containing 56% sucrose at 70-minute intervals for five weeks, and caries experience was evaluated. Animals infected with S. mutans with a mutated fruA gene only had statistically significant decreases in sulcal caries severity. Such a decrease was not observed in previous studies with ad libitum-fed animals (Wexler et al., 1992). The manifestation of diminished virulence in the programmed feeding model, but not in ad libitum-fed animals, supports the concept that the primary contribution of FruA to virulence is through the utilization of fructans storage polysaccharides. Animals infected with strains carrying the ftf mutation or simultaneous mutations in ftf and fruA did not display decreased virulence, perhaps indicating that sucrose utilization pathways may compete for substrate in vivo, or that accumulation of fructans may affect the ecology or the physicochemical characteristics of dental plaque in such a way as to reduce its cariogenic potential. The results of this study also emphasize that the contribution of a particular virulence determinant to the caries process may be highly dependent on the experimental design, feeding regimen and diet, and the presence or absence of other enzymatic activities.


Asunto(s)
Proteínas Bacterianas , Caries Dental/microbiología , Fructanos/metabolismo , Streptococcus mutans/metabolismo , Streptococcus mutans/patogenicidad , Animales , Placa Dental/microbiología , Modelos Animales de Enfermedad , Femenino , Genes Bacterianos , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Hexosiltransferasas/genética , Hexosiltransferasas/metabolismo , Masculino , Mutagénesis Insercional , Ratas , Ratas Sprague-Dawley , Organismos Libres de Patógenos Específicos , Streptococcus mutans/genética , Virulencia
16.
Clin Nutr ; 23(3): 355-61, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15158299

RESUMEN

BACKGROUND & AIM: Congestive heart failure (CHF) and anemia were reported to affect resting energy expenditure (REE). The aim of this study was to evaluate the effect of the correction of anemia on REE in subjects with CHF. PATIENTS AND METHODS: Nine anemic patients with compensated CHF and CRF were studied before and after correction of anemia. REE was studied by an open circuit indirect calorimeter, body composition by dual-energy-X-ray absorption and total body and extracellular water by multi-frequency bioelectrical impedence. Four anemic and 5 non-anemic CHF patients who did not receive any new treatment served as controls. RESULTS: After the correction of their anemia patients tended to increase weight (P<0.06), but no significant changes were observed in body composition. Daily caloric intake increased significantly (P<0.02). Ejection fraction increased (P<0.05) and pulse rate decreased significantly (P<0.001). REE and REEPP were in the normal range before correction but increased significantly afterwards (1402+/-256 vs. 1496+/-206 kcal/d, and 101+/-9 vs. 109+/-8, P<0.023 and P<0.006, respectively). CONCLUSION: Correction of anemia in patients with CHF increases their REE. This can be related either to improved tissue oxygenation and/or to increased caloric intake.


Asunto(s)
Anemia/metabolismo , Metabolismo Basal/fisiología , Composición Corporal/fisiología , Ingestión de Energía , Insuficiencia Cardíaca/metabolismo , Anciano , Anciano de 80 o más Años , Anemia/complicaciones , Anemia/terapia , Calorimetría Indirecta , Impedancia Eléctrica , Eritropoyetina/uso terapéutico , Femenino , Insuficiencia Cardíaca/complicaciones , Humanos , Hierro/administración & dosificación , Hierro/uso terapéutico , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Aumento de Peso
17.
Physiol Behav ; 35(2): 189-94, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4070381

RESUMEN

The study of the circadian sleep-wake cycle is beset by unique technical challenges. Continuous polygraphic recordings are necessary to characterize circadian phenomena; however, the traditional method of recording sleep at high (15 mm/sec) chart speed is impractical for continuous animal studies that may last several weeks at a stretch. A system to determine four sleep-wake stages (awake, transitional, non-REM, REM) from low chart speed (1.5 mm/sec) recordings was developed and validated by direct behavioral observation using four adult male squirrel monkeys prepared for chronic recording of EEG, EOG and EMG. The polygraphic stages "transitional," non-REM and REM were highly correlated with behavioral observations of sleep, although individual sleep stages could not be resolved by behavioral parameters alone.


Asunto(s)
Fases del Sueño/fisiología , Vigilia/fisiología , Animales , Electroencefalografía , Electromiografía , Electrooculografía , Masculino , Saimiri , Sueño REM/fisiología
18.
Laryngoscope ; 101(1 Pt 1): 50-5, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1984550

RESUMEN

The monothermal differential caloric test allows determination of vestibular recruitment and decruitment, variables which may help discriminate peripheral from central vestibular lesions. Previous reports indicated a strong association between vestibular recruitment and Menière's disease. This study examined patients having unilateral Menière's disease. Nystagmus beat frequency (NBF) and slow-component velocity (SCV) responses were recorded by electronystagmography (ENG). Electronystagmographic findings showing unilateral dysfunction were present in 54% of patients by slow-component velocity and in 31% by nystagmus beat frequency. Unilateral hypofunction was the most frequent lateralizing ENG finding. Absolute vestibular recruitment occurred in less than 10% of patients but relative recruitment was found in nearly 20% of patients. Slow-component velocity had higher sensitivity than nystagmus beat frequency, with excellent clinical concordance. Monothermal caloric testing as described in this study best detects peripheral vestibular disease in Meniere's patients using slow-component velocity to determine unilateral hypofunction and relative vestibular recruitment.


Asunto(s)
Enfermedad de Meniere/diagnóstico , Adolescente , Adulto , Anciano , Pruebas Calóricas/métodos , Electronistagmografía , Femenino , Humanos , Masculino , Enfermedad de Meniere/fisiopatología , Persona de Mediana Edad , Nistagmo Fisiológico , Postura , Tiempo de Reacción , Reclutamiento Neurofisiológico , Valores de Referencia , Vestíbulo del Laberinto/fisiopatología
19.
Laryngoscope ; 111(4 Pt 1): 634-41, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11359132

RESUMEN

OBJECTIVES/HYPOTHESIS: The traditional lateral-view cephalometric analysis is limited because it provides only two-dimensional analysis of the three-dimensional craniofacial structure. The objectives were to analyze lateral and frontal cephalometric radiographs in a series of normal patients and those with varying degrees of sleep-disordered breathing and to define the degrees of narrowing or other unfavorable anatomical changes that might differentiate the patients with sleep-disordered breathing from normal subjects. STUDY DESIGN: A prospective study of 100 adult patients with sleep-disordered breathing and 60 age-matched normal subjects. METHODS: An analysis of the lateral and frontal cephalometric measurements was performed to assess velopharyngeal anatomical features. A comparison was made between the patients' polysomnographic and cephalometric analyses. RESULTS: The compromised cephalometric parameters that may be found in patients with sleep-disordered breathing include acute skull-base and bony nasopharynx angles, inferior hyoid position, thickening of the velum, reduced retrovelar posterior air space along with thickening of the velum, thickening of the posterior pharyngeal wall, and narrowing of the velopharyngeal lumen. Worsening of sleep-disordered breathing was generally associated with increased numbers of compromised cephalometric parameters. As body mass index increases, there is reduced velopharyngeal width, the velum thickness is increased, and the posterior pharyngeal wall thickness is increased. CONCLUSIONS: Sleep-disordered breathing is associated with statistically significant changes in a number of cephalometric measurements. Frontal cephalometric analysis adds further information regarding the anatomical assessment of patients with upper airway obstruction, enhancing the traditional lateral cephalometric view.


Asunto(s)
Cráneo/diagnóstico por imagen , Síndromes de la Apnea del Sueño/diagnóstico , Índice de Masa Corporal , Estudios de Casos y Controles , Cefalometría , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Estudios Prospectivos , Radiografía , Cráneo/anatomía & histología , Síndromes de la Apnea del Sueño/diagnóstico por imagen
20.
Arch Otolaryngol Head Neck Surg ; 116(4): 483-5, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2317332

RESUMEN

Facial paralysis is an unusual manifestation of vestibular schwannoma, and generally signifies an advanced stage of tumor growth. We describe a case of eighth-nerve schwannoma that presented initially with rapid-onset complete unilateral facial paralysis. At the time of operation the nerve was found to be electrically intact despite marked compression by tumor. The facial nerve was preserved and facial motion has partially recovered postoperatively. All unexplained persistent facial paralysis should be evaluated by magnetic resonance imaging with paramagnetic contrast enhancement.


Asunto(s)
Neoplasias de los Nervios Craneales/complicaciones , Parálisis Facial/etiología , Neurilemoma/complicaciones , Nervio Vestibular , Adulto , Neoplasias de los Nervios Craneales/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética , Neurilemoma/diagnóstico , Factores de Tiempo
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