RESUMO
Numerous studies have explored the pathogenesis of cyclosporin A (CysA)-induced hypertension; however, none has assessed the impact of CysA treatment on resistance arteries in the setting of elevated blood pressure. Therefore, we studied the chronic effect of CysA on rat mesenteric artery resistance vessels (ex vivo). CysA (25 mg/kg per d for 7 d), but not vehicle, significantly raised systolic blood pressure (13.4 +/- 2.2 mmHg, P < 0.003, n = 9 per group). The resistance vessels from CysA-treated rats showed a small but significant decrease in norepinephrine sensitivity (P < 0.03) and a pronounced decrease in endothelium-dependent and -independent relaxation (P < 0.001) compared to controls. Endothelin-1 sensitivity tended to be diminished (P = 0.07). The direct (in vitro) effect of CysA was subsequently evaluated in resistance vessels from nontreated animals (n = 8) and exposed to CysA (2 micrograms/ml) for 24 h. As observed in vivo, CysA significantly decreased endothelium-dependent and -independent relaxations (P < 0.05) and attenuated norepinephrine sensitivity (P = 0.06). Methylene blue, a nitric oxide quencher, significantly inhibited the acetylcholine-induced relaxation in control, but not in CysA vessels, suggesting a selective action of CysA on the nitric oxide pathway. We conclude that CysA-induced hypertension is the consequence of a primary effect on resistance vessel relaxation, not increased vasoconstriction, as previously suggested.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Ciclosporina/efeitos adversos , Hipertensão/etiologia , Artérias Mesentéricas/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Endotelinas/farmacologia , Hipertensão/induzido quimicamente , Masculino , Azul de Metileno/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Nitroprussiato/farmacologia , Norepinefrina/farmacologia , Ratos , Ratos Sprague-Dawley , SístoleRESUMO
OBJECTIVES: In this study we investigated the centerline velocity profile method for flow computation as applied to noncircular, as well as circular, orifices using digital color flow data. BACKGROUND: Recently it has been suggested that flow volume through an orifice can be estimated more accurately by computing the axial "centerline" flow velocity/distance profile proximal to the orifice. METHODS: A total of seven different orifices were mounted in a constant-flow model: four circular orifices, two rectangular orifices with a major/minor axis ratio of 4:1 and 8:1 and an ovoid orifice having a major/minor axis ratio of 2:1. Three different flow rates were examined (1.68, 3.48 and 6.48 liters/min). Digital measurements of flow velocity at discrete positions along the centerline progressing toward the orifice were analyzed to yield complete flow velocity profiles for each orifice at each flow rate. RESULTS: A clear separation of the flow profiles for the three different flow rates was observed independent of orifice size for all of the circular orifices. The velocity/distance acceleration curves showed highly significant correlations using multiplicative regression fits (y = ax-b, r = 0.94 to 0.99, all p < 0.0001). An equation for quantitatively correlating the a and b coefficients from the multiplicative regression fits with flow rates was derived from stepwise regression analysis: Flow rate = 23a + 3.3b - 1.5 (r = 0.97, p < 0.0001, SEE 0.46 liter/min). CONCLUSIONS: In view of the various sizes and shapes encountered clinically for regurgitant orifices, the simplicity of this method for the estimation of the severity of regurgitant lesions might be of importance for clinical applications of this method.
Assuntos
Velocidade do Fluxo Sanguíneo , Ecocardiografia Doppler/métodos , Valvas Cardíacas/fisiopatologia , Hemorreologia , Modelos Cardiovasculares , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/fisiopatologia , Valvas Cardíacas/anatomia & histologia , Valvas Cardíacas/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador , Variações Dependentes do Observador , Fluxo Sanguíneo Regional , Análise de Regressão , Processamento de Sinais Assistido por ComputadorRESUMO
BACKGROUND: Despite widespread use of the automated blood pressure (BP) device (IVAC model 4200, IVAC Corporation, San Diego, Calif), there is little formal validation in the literature on its accuracy. OBJECTIVE: To assess the accuracy of the IVAC 4200 device, both under standardized conditions and as routinely used by ward staff, compared with the true indirect BP measured by mercury manometer (MM). METHODS: One hundred forty-five stable inpatients were randomly selected for BP measurements by 3 randomly ordered protocols: (1) MM performed by certified investigators, (2) IVAC 4200 BP performed by trained investigators (research automated [RA]), and (3) IVAC 4200 BP performed by ward personnel (ward automated [WA]). RESULTS: For RA compared with MM ("true" indirect BP), 59% of systolic and 54% of diastolic readings were within 5 mm Hg and 83% of systolic and 86% of diastolic were within 10 mm Hg for a British Hypertension Society grade C for both. For WA compared with MM, 40% of systolic and 50% of diastolic readings were within 5 mm Hg and 70% of systolic and 80% of diastolic readings were within 10 mm Hg for British Hypertension Society grades D and C, respectively. The presence of arrhythmias and/or low K5 values (fifth phase of Korotkoff sounds <30 mm Hg) significantly increased the inaccuracy for diastolic values. Inappropriate cuff selection significantly increased inaccuracy of systolic BP (WA vs MM). CONCLUSIONS: The IVAC 4200 yields substandard estimates of systolic and diastolic BP even under standardized, thus optimum conditions. The presence of arrhythmias or low K5 values and the selection of inappropriate cuff size by the ward staff also contributed to inaccuracy.
Assuntos
Determinação da Pressão Arterial/normas , Hipertensão/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Determinação da Pressão Arterial/instrumentação , Feminino , Humanos , Hipertensão/classificação , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Reino UnidoRESUMO
BACKGROUND: Adherence to dietary recommendations for disease management is often hindered by the complexity of incorporating them into the daily diet. Nutrition and cardiovascular scientists and food technologists collaborated to develop a prepared meal plan that meets national dietary guidelines for cardiovascular risk reduction. OBJECTIVE: To assess the clinical effects of this plan, which incorporates all National Academy of Sciences National Research Council recommended dietary allowances for vitamins, minerals, and macronutrients, compared with a patient-selected American Heart Association Step I and Step II diet plan. METHODS: This multicenter, randomized, parallel-intervention trial was conducted at 10 medical centers in the United States and Canada and involved 560 men and women with hypertension, dyslipidemia, or diabetes. Following calculation of prescriptions to meet individual nutritional requirements based on the Harris-Benedict equation, participants were randomized to the Campbell's Center for Nutrition and Wellness (CCNW) plan, which is composed of prepackaged breakfast, lunch, and dinner meals provided to participants, or a nutritionist-guided American Heart Association Step I and Step II diet, in which participants self-selected foods to meet their nutrition prescription for 10 weeks. MAIN OUTCOME MEASURES: Blood pressure (BP); lipid, glucose, glycosylated hemoglobin (HbA1c), and insulin levels; body weight; dietary intake; and quality of life. RESULTS: Patients' BP, lipid levels, carbohydrate metabolism, weight, and quality of life (P < or = .001 for all findings except low-density lipoprotein-high-density lipoprotein ratio, P = .25) all improved on both nutrition plans. Mean differences (+/-SD) between baseline and treatment clinical values for the CCNW and the self-selected diet groups (between-group P values), respectively, were as follows: systolic BP, -6.4 +/- 9.2 mm Hg and -4.6 +/- 9.0 mm Hg (P = .02); diastolic BP, -4.2 +/- 5.7 mm Hg and -3.0 +/- 5.1 mm Hg (P = .006); cholesterol, -0.32 +/- 0.58 mmol/L and -0.27 +/- 0.56 mmol/L (-12.4 +/- 22.5 mg/dL and -10.4 +/- 21.9 mg/dL) (P = .30); glucose, -0.65 +/- 1.88 mmol/L and -0.75 +/- 2.03 mmol/L (-11.7 +/- 34.0 mg/dL and -13.5 +/- 36.6 mg/dL) (P = .10); and HbA1c, -0.4% +/- 0.8% and -0.3% +/- 0.7% (P = .66). Weight loss with the CCNW and self-selected plans, respectively, was as follows: men, -4.5 +/- 3.6 kg and -3.5 +/- 3.3 kg; and women, -4.8 +/- 3.0 kg and -2.8 +/- 2.8 kg. Quality of life was significantly improved for daily and work activities (P < .05) and nutritional health perceptions (P < .05) with the CCNW plan relative to the self-selected group. Overall nutrient intake and compliance were both significantly (P < .001) better with the CCNW plan. CONCLUSIONS: Nutritionally balanced meals that meet the recommendations of national health organizations improved multiple risk factors for patients with cardiovascular disease. The CCNW plan resulted in greater clinical benefits, nutritional completeness, and compliance than the self-selected diet. The CCNW is a comprehensive nutrition plan, convenient for both prescription and practice, and appears viable for effecting favorable dietary changes in patients at high risk for cardiovascular disease.
Assuntos
Doenças Cardiovasculares/dietoterapia , Doenças Cardiovasculares/etiologia , Dietoterapia , Adulto , Idoso , Pressão Sanguínea , Peso Corporal , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Carboidratos da Dieta/metabolismo , Feminino , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores de RiscoRESUMO
Current dietary recommendation for cardiovascular disease risk reduction and recommended dietary allowances (RDAs) were used to develop a nutritionally complete prepackaged prepared meal plan specifically designed to reduce the risk of cardiovascular disease. In the current study we tested patient acceptance of the diet as defined by measures of quality of life. In a randomized, parallel-design, multicenter clinical trial, 77 persons with hypertension, diabetes mellitus, dyslipidemia, or a combination of two or more of these conditions were recruited and randomly assigned to either a prepared meal plan (n = 39) or a comparable self-selected diet (n = 38) for 10 wk. The prepared meal plan met both the RDAs for all essential micronutrients and the dietary recommendations of national health organizations for macronutrients, cholesterol, sodium, and fiber. The prescribed self-selected diet was matched for macronutrients. Quality of life, as measured by a battery of instruments, was the major endpoint. Individuals consuming the prepared meal plan had significant improvements in mental health (P < 0.01), general perceived health (P < 0.005), daily activities (P < 0.05), work performance (P < 0.005), affect (P < 0.01), and nutritional health perceptions (P < 0.001), and reductions in nutrition hassles based on a standardized questionnaire (P < 0.001). The self-selected-diet group had significant improvements in nutritional health perceptions (P < 0.001) and affect (P < 0.001). There were significant improvements in weight (P < 0.001), blood pressure (P < 0.001), cholesterol (P < 0.002), low-density lipoproteins (P < 0.001), glucose (P < 0.014), and glycated hemoglobin (Hb A(1c) (P < 0.004) that were comparable in both groups. In summary, this study shows that a nutritionally complete diet, whether prepackaged or self-selected, improves multiple risk factors for cardiovascular disease. The prepackaged prepared meal plan had the added benefit of a greater improvement in quality of life.
Assuntos
Doenças Cardiovasculares/dietoterapia , Doenças Cardiovasculares/fisiopatologia , Qualidade de Vida , Glicemia/análise , Pressão Sanguínea/fisiologia , Peso Corporal/fisiologia , Doenças Cardiovasculares/metabolismo , Colesterol/sangue , Diabetes Mellitus/dietoterapia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Dietoterapia/normas , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hiperlipidemias/dietoterapia , Hiperlipidemias/metabolismo , Hiperlipidemias/fisiopatologia , Hipertensão/dietoterapia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Necessidades Nutricionais , Satisfação do Paciente , Fatores de Risco , Autoimagem , Inquéritos e QuestionáriosRESUMO
Noncompliance with therapeutic diets remains a major obstacle to achieving improvements in cardiovascular disease (CVD) morbidity and mortality. This study compared dietary compliance and CVD risk factor response to two dietary interventions designed to treat hypertension, dyslipidemia, and diabetes mellitus. In a multicenter trial, 560 adults were randomly assigned to either a self-selected, mixed-food plan (n = 277), or a nutrient-fortified prepared meal plan (n = 283); each was designed to provide 15-20% of energy from fat, 55-60% from carbohydrate, and 15-20% from protein. Nutrient intake was estimated from 3-d food records collected biweekly throughout the 10-wk intervention. Compliance was determined by evaluating the participants' ability to meet specific criteria for energy intake [+/-420 kJ (100 kcal) from the midpoint of the prescribed energy range], fat intake (< 20%, < 25%, or < 30% of energy from total fat), and the National Cholesterol Education Program/American Heart Association Step 1 and 2 diet recommendations. Compliance with energy, fat, and Step 1 and 2 criteria was better in participants who followed the prepared meal plan than in those who followed the self-selected diet (P < 0.0001). Compliant participants in both groups achieved greater reductions in body weight, systolic and diastolic blood pressure, and total and low-density-lipoprotein cholesterol than noncompliant participants (P < 0.05). In general, better endpoint responses were observed with lower fat intakes regardless of group assignment. The prepared meal plan is a simple and effective strategy for meeting the many nutrient recommendations for CVD risk reduction and improving dietary compliance and CVD endpoints.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Cooperação do Paciente , Adulto , Idoso , Pressão Sanguínea , Metabolismo dos Carboidratos , Doenças Cardiovasculares/dietoterapia , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/prevenção & controle , Registros de Dieta , Feminino , Humanos , Hiperlipidemias/dietoterapia , Hiperlipidemias/prevenção & controle , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Fatores de RiscoRESUMO
BACKGROUND: Elevated blood homocysteine is a risk factor for cardiovascular disease. A 5-micromol/L increase is associated with an approximately 70% increase in relative risk of cardiovascular disease in adults. For patients with established risk factors, this risk is likely even greater. OBJECTIVE: Effects of increased dietary folate and recommended intakes of vitamins B-12 and B-6 on serum total homocysteine (tHcy) were assessed in individuals at high risk of cardiovascular disease. DESIGN: This trial was conducted at 10 medical research centers in the United States and Canada and included 491 adults with hypertension, dyslipidemia, type 2 diabetes, or a combination thereof. Participants were randomly assigned to follow a prepared meal plan (PMP; n = 244) or a self-selected diet (SSD; n = 247) for 10 wk, which were matched for macronutrient content. The PMP was fortified to provide >/=100% of the recommended dietary allowances for 23 micronutrients, including folate. RESULTS: Mean folate intakes at 10 wk were 601 +/- 143 microgram/d with the PMP and 270 +/- 107 microgram/d with the SSD. With the PMP, serum tHcy concentrations fell from 10.8 +/- 5.8 to 9.3 +/- 4.9 micromol/L (P < 0.0001) between weeks 0 and 10 and the change was associated with increased intakes of folate, vitamin B-12, and vitamin B-6 and with increased serum and red blood cell folate and serum vitamin B-12 concentrations. tHcy concentrations did not change significantly with the SSD. CONCLUSIONS: The PMP resulted in increased intakes and serum concentrations of folate and vitamin B-12. These changes were associated with reduced serum tHcy concentrations in persons at high risk of cardiovascular disease.
Assuntos
Doenças Cardiovasculares/etiologia , Dieta , Ácido Fólico/uso terapêutico , Homocisteína/sangue , Piridoxina/uso terapêutico , Vitamina B 12/uso terapêutico , Adulto , Idoso , Análise de Variância , Diabetes Mellitus Tipo 2/complicações , Feminino , Ácido Fólico/administração & dosagem , Alimentos Fortificados , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Piridoxina/administração & dosagem , Fatores de Risco , Vitamina B 12/administração & dosagemRESUMO
PURPOSE/OBJECTIVE: The measurement of complex dose distributions (those created by irradiation through multiple beams, multiple sources, or multiple source dwell positions) requires a dosimeter that can integrate the dose during a complete treatment. Integrating dosimeter devices generally are capable of measuring only dose at a point (ion chamber, diode, TLD) or in a plane (film). With increasing use of conformal dose distributions requiring shaped, noncoplanar beams, there will be an increased requirement for a dosimeter that can record and display a 3D dose distribution. The use of a 3D dosimeter will be required to confirm the accuracy of treatment plans produced by the current generation of 3D treatment-planning computers. METHODS AND MATERIALS: The use of a Fricke-infused gel and magnetic resonance imaging (MRI) to demonstrate the localization of stereotactic beams has been demonstrated (11). The recently developed BANG polymer gel dosimetry system (MGS Research, Inc., Guilford, CT), based on radiation-induced chain polymerization of acrylic monomers dispersed in a tissue-equivalent gel, surpasses the Fricke-gel method by providing accurate, quantitative dose distribution data that do not deteriorate with time (6, 9). The improved BANG2 formulation contains 3% N,N'-methylene-bisacrylamide, 3% acrylic acid, 1% sodium hydroxide, 5% gelatin, and 88% water, where all percentages are by weight. The gel was poured into volumetric flasks, of dimensions comparable to a human head. The gels were irradiated with complex beam arrangements, similar to those used for conformal radiation therapy. Images of the gels were acquired using a Siemens 1.5T imager and a Hahn spin-echo pulse sequence (90 degrees-tau-180 degrees-tau-acquire, for different values of tau). The images were transferred via network to a Macintosh computer for which a data analysis and display program was written. The program calculates R2 maps on the basis of multiple TE images, using a monoexponential nonlinear least-squares fit based on the Levenberg-Marquardt algorithm. The program also creates a dose-to-R2 calibration function by fitting a polynomial to a set of dose and R2 data points, obtained from gels irradiated in test tubes to known doses. This function can then be applied to any other R2 map, so that a dose map can be computed and displayed. RESULTS: Through exposure to known doses of radiation, the gel has been shown to respond linearly with dose in the range of 0 to 10 Gy, and its response is independent of the beam energy or modality. Dose distributions have been imaged in orthogonal planes, and can be displayed in a convenient form for comparison with isodose plans. The response of the gel is stable; the gel can be irradiated at any time after its manufacture, and imaging can be conducted any time following a brief interval after irradiation. CONCLUSION: The polymer gel dosimeter has been shown to be a valuable device for displaying three-dimensional dose distributions. The imaged dose distribution can be compared easily with calculated dose distributions, to validate a treatment planning system. In the future, gels may be prepared in anthropomorphic phantoms, to confirm unique patient dose distributions.
Assuntos
Géis , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Polímeros , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Géis/química , Humanos , Polímeros/química , Dosagem RadioterapêuticaRESUMO
Patients with essential hypertension have been reported to have a higher serum concentration of parathyroid hormone (PTH) than normotensive individuals although this finding is not universal among studies. To further characterize the status of the calcium regulating hormones in essential hypertension, we measured the parathyroid gland response to acute EDTA-induced hypocalcemia and the renal response of 1,25(OH)2-vitamin D to dietary calcium deprivation in 16 hypertensive (H) and 15 normotensive (N) men. The average mean arterial blood pressure once all antihypertensive medications were discontinued was 108 +/- 7 mm Hg for the hypertensive group and 89 +/- 4 mm Hg for the normotensive group (P < .01). There were no group differences in baseline serum concentrations of ionized calcium, creatinine, intact PTH, and 1,25(OH)2-vitamin D, urinary calcium excretion, and creatinine clearance. After a 1-h infusion of EDTA at 12.5 mg/kg/h, the serum concentration of ionized calcium fell (H: 1.25 +/- .03 to 1.17 +/- .04 mmol/L, N: 1.26 +/- .04 to 1.18 +/- .04 mmol/L, P = NS) and PTH increased (H: 36 +/- 9 to 91 +/- 30 pg/mL, N: 40 +/- 14 to 85 +/- 28 pg/mL, P = NS). With an additional hour of EDTA at a dose of 25 mg/kg/h, serum ionized calcium concentration fell further (H: 1.01 +/- .05 mmol/L, N: 1.03 +/- .06 mmol/L, P = NS) and PTH increased to 150 +/- 58 pg/ml in patients and 130 +/- 32 pg/ml in controls (P < .001). The response suggested an increased maximal parathyroid gland secretory capacity in the hypertensive patients relative to the controls. There was no group difference in the serum concentration of 1,25(OH)2-vitamin D at baseline (H: 32 +/- 6 pg/ml, N: 32 +/- 8 pg/ml, P < .90) and following dietary calcium deprivation for three days (H 50 +/- 12, N 48 +/- 14 P < 0.76). The maximal stimulated PTH level was significantly higher in hypertensive than normotensive subjects in the absence of measured differences in serum ionized calcium concentration, serum 1,25(OH)2-vitamin D concentration, and creatinine clearance. These findings suggest an intrinsic alteration of PTH regulation in patients with essential hypertension, manifest as increased parathyroid gland secretory capacity.
Assuntos
Calcitriol/sangue , Hipertensão/sangue , Hormônio Paratireóideo/sangue , Adolescente , Adulto , Idoso , Cálcio da Dieta/administração & dosagem , Ácido Edético , Humanos , Hipocalcemia/sangue , Hipocalcemia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Valores de ReferênciaRESUMO
An intravenous glucose tolerance test (IVGTT) was performed on 16 spontaneously hypertensive rats (SHR) and 15 Wistar-Kyoto rats (WKY) by challenging them with an intravenous glucose load of 0.125 g/100 g body weight. Serum glucose and insulin were measured at 0, 15, 30, 60, 120, and 240 min. In a second experiment, oral glucose tolerance testing (OGTT) was performed with a glucose load of 170 mg/100 g body weight. Serum glucose and insulin were measured at 0, 30, 60, 120, and 240 min. A third experiment examined in vivo insulin-stimulated peripheral glucose uptake via the insulin suppression test. Glucose (8 mg/kg/min), insulin (2.5 to 4.0 mU/kg/min), and somatostatin (1 ng/kg/min) were infused for 3 h. Steady state serum glucose (SSSG) and serum insulin (SSSI) were determined at 0, 140, 160, and 180 min. IVGTT data indicated that serum glucose values were significantly increased in the WKY compared to the SHR at 15, 30, 60, and 120 min. Glucose clearance rates between 15 and 60 min were significantly (P less than .0001) lower in WKY (0.65 +/- 0.07%/min) compared to SHR (1.91 +/- 0.17%/min). The SHR exhibited an exaggerated 15-min peak in insulin secretion that was lacking in the WKY in response to an intravenous glucose load. OGTT data also indicated that the area under the serum insulin curves was higher in the WKY than in the SHR (P less than .017). Peripheral insulin sensitivity showed that despite comparable SSSI levels between the two strains, SSSG values were 31% higher in the SHR compared to the WKY (P less than .001). Thus, it appears that the WKY has a diminished insulin secretory capacity in response to a glucose load, while the SHR has lower tissue responsiveness to insulin's action.
Assuntos
Hipertensão/metabolismo , Insulina/metabolismo , Ratos Endogâmicos SHR/metabolismo , Administração Oral , Animais , Glicemia/metabolismo , Glucose/administração & dosagem , Glucose/farmacologia , Teste de Tolerância a Glucose , Hipertensão/fisiopatologia , Injeções Intravenosas , Insulina/farmacologia , Resistência à Insulina/fisiologia , Secreção de Insulina , Masculino , Modelos Biológicos , Ratos , Ratos Endogâmicos WKY , Somatostatina/farmacologiaRESUMO
To study physiologic factors affecting the blood pressure (BP) response to nonpharmacologic maneuvers, fasting blood glucose, insulin, lipid and mineral levels, urinary mineral excretion, and the calcium regulating hormones parathyroid hormone (PTH) and 1,25 dihydroxyvitamin D (1,25 (OH)2D) were measured in 71 unmedicated hypertensive (26 hypertensive only [HT], 45 hypertensive hyperlipidemic [HTHL]), and 87 normotensive hyperlipidemic (NTHL) control subjects before and during a 10-week multicenter, randomized controlled trial comparing a prepared meal plan (CCNW) with a self-selected diet (SSD) based on nutritionist counseling. Blood pressure fell to a greater extent in hypertensive versus normotensive subjects (-8+/-1/-5+/-1 v -2+/-1/-2+/-1 mm Hg, P < .0001/P < .0001), and on CCNW versus SSD diets (delta systolic BP [SBP]/delta diastolic BP [DBP], P = .033/P = .002). Diet-induced weight change was the strongest correlate of changes in BP (SBP: r = 0.360, P < .0001; DBP: r = 0.414, P < .0001), which, on multivariate analysis for deltaSBP, could partly be accounted for by diet-induced changes in fasting glucose (r = 0.215, P = .009) and cholesterol (r = 0.219, P = .006) levels. Independently of weight, diet-induced changes in SBP also were significantly related to concomitant changes in urinary excretion of potassium (r = -0.285, P = .001), magnesium (r = -0.254, P = .003), and calcium relative to sodium (r = -0.200, P = .021), but not to sodium per se; and to changes in serum potassium (r = -0.249, P = .002), phosphorus (r = -0.279, P = .001), PTH (r = 0.288, P = .0006), and 1,25 D (r = 0.202, P = .017). We conclude that the ability of diet to lower BP successfully may result from the additive contributions of multiple components. Independently of weight loss and the associated changes in circulating glucose and cholesterol, BP is influenced by the increasing provision of minerals such as potassium, magnesium, and calcium, perhaps by virtue of their suppressive effects on circulating vasoactive calcium regulating hormones.
Assuntos
Pressão Sanguínea , Hipertensão/dietoterapia , Hipertensão/fisiopatologia , Adulto , Cálcio/urina , Dieta , Feminino , Humanos , Magnésio/urina , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Potássio/sangue , Potássio/urina , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Sístole , Redução de PesoRESUMO
Increased arterial pressure is known to be influenced by a variety of nutrients. Compliance with dietary recommendations for risk reduction is often limited by the complexity of their implementation. In addition, how improvements in total diet, rather than single nutrients, influence concomitant cardiovascular risk factors has not been thoroughly explored. We assessed the effects of a nutritionally complete prepared meal program, the Campbell's Center for Nutrition and Wellness plan (CCNW), compared with dietary therapy in which participants received a structured nutritional assessment and prescription and selected their own foods, in 101 women and men with mild-to-moderate hypertension. Outcome measures included blood pressure (BP), lipids and lipoproteins, glucose, glycosylated hemoglobin (HbA1c), insulin, homocysteine, nutrient intake, compliance, and quality of life. Both dietary interventions significantly lowered BP (P < .0001), while simultaneously improving the overall cardiovascular risk profile. Significantly greater benefits were observed with the CCNW plan as compared with the participant selected diet in cholesterol and LDL levels (both P < .0001), LDL:HDL (P < .001), HbA1c (P < .05), homocysteine (P < .001), total nutrient intake (P < .0001), compliance (P < .0001), and quality of life (P < .001). This study demonstrates that improving the total diet to include the full array of recommended dietary guidelines, rather than focusing on single nutrients, has significant benefits for the cardiovascular risk profile of hypertensive persons beyond BP control. Compared with typical dietary therapy, the comprehensive CCNW meal plan has significantly greater effects on multiple cardiovascular risk factors while yielding greater compliance and improved quality of life.
Assuntos
Hipertensão/dietoterapia , Adulto , Idoso , Pressão Sanguínea , Peso Corporal , Método Duplo-Cego , Feminino , Alimentos Formulados , Homocisteína/sangue , Humanos , Hipertensão/etnologia , Hipertensão/metabolismo , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Cooperação do Paciente , Qualidade de Vida , Fatores de RiscoRESUMO
Continuous wave Doppler methods have been widely used clinically for evaluating the severity of aortic regurgitation; however, there have been no studies comparing these continuous wave Doppler methods with a strictly quantifiable reference for regurgitant severity. The purpose of this study was to test the applicability of continuous wave Doppler methods (deceleration slope and pressure half-time) for evaluation of chronic aortic regurgitation in an animal model. Eight sheep were studied 8 to 20 weeks after surgery to create chronic aortic regurgitation. Twenty-nine hemodynamically different states were obtained pharmacologically. A Vingmed 775 system was used for recording continuous wave Doppler traces with a 5 MHz annular array transducer directly placed on the heart near the apex. The aortic regurgitation was quantified as peak and mean regurgitant flow rates, regurgitant stroke volumes and regurgitant fractions determined with pulmonary and aortic electromagnetic flow probes and meters balanced against each other. Peak regurgitant flow rates varied from 1.8 to 13.6 L/min (6.3 +/- 3.2 L/min) (mean +/- SD), mean regurgitant flow rates varied from 0.7 to 4.9 L/min (2.7 +/- 1.3 L/min), regurgitant stroke volume varied from 7.0 to 48.0 ml/beat (26.9 +/- 12.2 ml/beat), and regurgitant fraction varied from 23% to 78% (53% +/- 16%). Only marginal correlations were obtained between reference indexes and continuous wave Doppler deceleration slope and pressure half-time (r = 0.55 to 0.74). A deceleration slope greater than 3 m/sec2 and pressure half-time less than 400 msec did, however, provide 100% specificity for detecting severe AR (regurgitant fraction > 50%). Our study shows that the continuous wave Doppler deceleration slope and pressure half-time methods have limited use for quantifying aortic regurgitation.
Assuntos
Insuficiência da Valva Aórtica/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Animais , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo , Cateterismo Cardíaco , Doença Crônica , Hemodinâmica , Ovinos , Volume SistólicoRESUMO
OBJECTIVE: To compare a nutritionally complete prepared meal plan that meets national dietary guidelines to usual-care dietary therapy for hypertension, dyslipidemia, and glycemic control. DESIGN: Randomized, controlled trial. SUBJECTS/SETTING: Outpatients with hypertension, dyslipidemia, or diabetes mellitus (n = 251) were recruited at 6 medical centers in the United States and Canada. INTERVENTION: The prepared meal plan, which was developed by university-based nutrition and cardiovascular scientists and food technologists at Campbell's Center for Nutrition & Wellness (CCNW), provided the optimal levels of macronutrients and micronutrients recommended for cardiovascular risk reduction in a variety of prepackaged meals and snacks. After a 4-week pretrial period to assess baseline state, participants were randomized to the CCNW plan or "usual-care" diet for 10 weeks. MAIN OUTCOME MEASURES: Blood pressure, carbohydrate metabolism, lipoproteins, homocysteine, weight, nutrient intake, compliance. STATISTICAL ANALYSES PERFORMED: Repeated measures analysis of variance. RESULTS: Lipoproteins, carbohydrate metabolism, blood pressure, and weight improved on both plans. Mean differences (+/- standard deviation) between baseline and follow-up for the CCNW plan and the usual-care plan, respectively, were total cholesterol, -0.41 +/- 0.64 and -0.20 +/- 0.50 mmol/L (between-group P < .01); plasma glucose, -0.7 +/- 1.7 and -0.3 +/- 1.3 mmol/L (P < .05); systolic blood pressure, -5.2 +/- 10.0 and -4.7 +/- 9.0 mm Hg (P = .67), diastolic blood pressure, -3.8 +/- 5.9 and -2.2 +/- 5.5 mm Hg (P < .05); and homocysteine, -1.3 +/- 3.8 and 0.2 +/- 3.4 mumol/L (P < .01). The CCNW plan led to greater weight loss than the usual-care diet (-5.5 +/- 3.8 kg vs -3.0 +/- 3.2 kg, P < .0001). APPLICATIONS/CONCLUSION: The nutritionally complete CCNW plan offers greater improvements in lipids, blood sugars, homocysteine, and weight loss than usual-care diet therapy. This prepackaged comprehensive nutrition program can augment both the prescription and practice of optimal dietary therapy.
Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Dieta/normas , Hiperlipidemias/dietoterapia , Hipertensão/dietoterapia , Adulto , Idoso , Glicemia/análise , Pressão Sanguínea , Colesterol/sangue , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta/efeitos adversos , Feminino , Hemoglobinas Glicadas/análise , Homocisteína/sangue , Humanos , Hiperlipidemias/prevenção & controle , Hipertensão/prevenção & controle , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Cooperação do Paciente , Fatores de Risco , Resultado do Tratamento , Redução de PesoRESUMO
Sensitive research issues call for anonymous questionnaires. This makes accurately matching pretests with posttests difficult or impossible. Various subject-generated coding schemes have been developed, but their accuracy has been unknown. This anonymous study, with 745 students, used subject-generated coding to match pretests with posttests. The matching was verified for accuracy with the use of a collateral, anonymous, sticker identification system. The coding system was able to accurately match 75.2% of all the pretest-posttest pairs. An additional 22.1% of the pairs were left unmatched and only 2.7% were matched incorrectly. Subject-generated coding systems can be very effective where confidentiality is important to protect.
Assuntos
Confidencialidade , Inquéritos e Questionários , Adolescente , Criança , Currículo , Avaliação Educacional , Feminino , Educação em Saúde , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Projetos de PesquisaRESUMO
The present study examined the use of a progressive delay procedure to teach self-control to two groups of dually diagnosed adults. When given a choice between an immediate smaller reinforcer and a larger delayed reinforcer, both groups chose the smaller reinforcer during baseline. During treatment, progressive increases in work requirements for gaining access to a larger reinforcer resulted in both groups selecting larger delayed reinforcers. The results are discussed with respect to increasing cooperative work behavior and self-control.
Assuntos
Controle Interno-Externo , Transtornos Mentais/terapia , Autoeficácia , Ensino , Adulto , Feminino , Humanos , Deficiência Intelectual/complicações , Masculino , Transtornos Mentais/complicações , Transtornos Mentais/psicologia , Reforço PsicológicoRESUMO
OBJECTIVES: Our goal was to describe how physician knowledge of patients' families affects the processes of patient care in family practices. STUDY DESIGN: Using a multimethod comparative case study design, detailed dictated field notes were recorded after direct observation of patient encounters and the office environment as part of the Prevention and Competing Demands in Primary Care Study. We identified domains of outpatient visits in which patients were accompanied by a family member or in which family-oriented content was discussed. POPULATION: Outpatient encounters with 1637 patients presenting in 18 family practices in the Midwest were analyzed using an editing style. OUTCOMES: We developed a typology for ways in which family context affects outpatient visits. RESULTS: Patients were accompanied during 35% of all outpatient visits, the vast majority of these visits involving children. Family history or a family member's problems were discussed during 35% of visits during which no family member was present. An analysis of these "family-oriented" visits resulted in a typology of 6 ways that family context informs and affects the outpatient visit: (1) using family social context to illuminate patient disease, illness, and health; (2) using family to discover the source of an illness; (3) discussing and managing the health and illness of family members; (4) family concern for patient's health; (5) using the family as a care resource and care collaborator; and, (6) giving family members unscheduled care. CONCLUSION: Family context is an important feature of family practice that influences the processes of patient care. Since family-oriented care is an essential feature of family practice, outcomes of this largely hidden part of care deserve further study.
Assuntos
Medicina de Família e Comunidade , Família , Visita a Consultório Médico , Relações Profissional-Família , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Família/psicologia , Saúde da Família , Medicina de Família e Comunidade/organização & administração , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Nebraska , Observação , Qualidade da Assistência à SaúdeRESUMO
Cardiac complications of Marfan syndrome can be fatal. This article reviews the assessment of a patient with this hereditary disorder, complications and their treatment, and nursing care.
Assuntos
Cardiopatias/etiologia , Cardiopatias/enfermagem , Síndrome de Marfan/complicações , Síndrome de Marfan/enfermagem , Dilatação Patológica , Cardiopatias/diagnóstico , Humanos , Síndrome de Marfan/diagnósticoRESUMO
Gwinnett Health System. Lawrenceville, Ga., has successfully filled 15 vacant RN positions on two units with interns in critical care. This "grow your own" approach resulted in an ICU turnover rate of less than 15% per year.
Assuntos
Cuidados Críticos , Educação Continuada em Enfermagem/organização & administração , Capacitação em Serviço/organização & administração , Internato não Médico/organização & administração , Recursos Humanos de Enfermagem Hospitalar/educação , Humanos , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Recursos HumanosRESUMO
This article describes development and testing of a tool for determining an appropriate reward for staff performance in a critical care area. Outlined is the process of identifying and quantifying appropriate merit increases based on bedside performance as well as participation in other unit, hospital, professional and community activities. Positive results are reported after one- and two-year use.