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1.
Cave Hill; s.n.; 1991. ix,151 p. ill, tabs.
Tese em Inglês | MedCarib | ID: med-8699

RESUMO

The relationships between hypertension, diabetes, potassium status and other factors were examined in a population-based sample of 464 Barbadians. A stratified random sample by gender and age (40-79 years) was obtained from enumeration registers and investigated over a three month period. The previously reported low potassium range for Barbadians was confirmed (2.9-4.7 mmol/l). Within-subject correlation of plasma potassium and 24-hour urine potassium was demonstrated by repeat investigation in 70 subjects one year later. A high prevalence of obesity, hypertension and diabetes was confirmed in this population with relatively good health care. The prevalence of hypertension (by history) was 36 percent in the whole sample. Twenty-six percent of subjects were receiving antihypertensives, yet a diastolic BP of >90 mmHg was found in 17 percent of the whole sample. Six percent of subjects had a fasting plasma glucose greater than that cited by WHO. Subjects not on thiazides, compared to those on thiazides did not show a significant difference in fasting glucose or potassium values, but did show higher uric acid and cholesterol values. Dietary analyses confirmed the traditional high starch, low fruit Barbadian diet. The major risk factors for hypertension were female gender, obesity in females and positive family history. In this study a high prevalence of hypokalemia and moderately low dietary potassium has been demonstrated, but neither potassium deficiency nor thiazide use appeared to be definitely linked to diabetes or hypertension.


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Hipertensão/epidemiologia , Diabetes Mellitus/epidemiologia , Potássio/sangue , Potássio/urina , Barbados , Obesidade , Hipopotassemia , Sódio/efeitos adversos
2.
West Indian med. j ; 39(Suppl. 1): 45, Apr. 1990.
Artigo em Inglês | MedCarib | ID: med-5272

RESUMO

The aims of this study were to assess the previously reported hypokalaemia in black Barbadians and investigate relationships between hypertension (diastolic bloodpressue > 90mm Hg and/or systolic bloodpressure > 160mm Hg), diabetes mellitus (DM, fasting plasma glucose > 7.8 mmol/l), diet and potassium (K) status in Barbadians. A stratified random sample by sex and age (40-70 years) was obtained from enumeration registers of a geographically defined area. Of 955 persons invited, 464 (48.6 per cent) responded and they comprised 190 men and 274 women. A general and a food frequency questionnaire for 24-hr. diet recall were administered, and height, weight and bloodpressure (BP) were measured. Fasting plasma glucose, K and sodium levels were measured in blood, and urine volume, sodium and K were determined in a 24-hr. urine collection. The mean plasma of K was 3.8 mmol/l, S.D. 0.44, giving a range (mean ñ 2 S.D.) of 2.9 - 4.7 mmol/l which was almost identical to that previously reported. Both 24-hr. urinary K and sodium showed a weak negative correlation with systolic BP only. K deficiency was not clearly linked to hypertension and neither K deficiency nor current thiazide use was linked to DM. The prevalence of hypertension (25 per cent), DM (11 per cent), obesity, hypokalaemia and moderately low dietary K were high (AU)


Assuntos
Humanos , Masculino , Feminino , Hipertensão , Diabetes Mellitus , Potássio , Hipopotassemia , Fatores Sexuais , Fatores Etários , Barbados , Obesidade
3.
Clin Sci ; 76: 199-203, 1989.
Artigo em Inglês | MedCarib | ID: med-5055

RESUMO

One hundred and five primigravidae were followed sequentially at 4-weekly intervals starting at gestational week 31. They were seen again at 6 weeks post partum. At each visit measurement were made of blood pressure as well as of leucocyte and erythrocyte sodium and potassium content. Eighty-five subjects completed the study. Seven developed pre-eclampsia. In both controls and patients who developed pre-eclampsia, leucocyte and erythrocyte sodium content increased with gestational age and fell post partum. These changes were of greater magnitude in the patients with pre-eclampsia. Cell potassium fell in both groups, but to a greater extent in patients with pre-eclampsia. These changes in cell sodium paralleled those in blood pressure in both groups. These data suggest that the excessive blood pressure changes in pre-eclampsia might be related to similar changes in cell sodium content (AU)


Assuntos
Humanos , Gravidez , Recém-Nascido , Pré-Eclâmpsia , Hipertensão , Sódio , Potássio , Jamaica
4.
Kingston; 1989. xix,199 p. tab.
Tese em Inglês | MedCarib | ID: med-13760

RESUMO

In the present study twenty-seven hypertensive patients, thirty-five normotensives without familial hypertension and twelve normotensives with familial hypertension were studied cross-sectoinally with regard to their age, sex, body mass index and - most important of all - the electrolyte (sodium and potassium) composition of their red and white blood cells. The major aim of this study was to find out if there were differences between the above mentioned subject groups regarding the electrolyte composition (sodium and potassium) of their blood cells. Another aim of this study was to characterize, through multiple regression analysis, the relationship between blood pressure, body mass index, and cell sodium and potasssium. Higher RBC-Na and WBC-Na were observed in essential hypertensives and normotensives with familial hypertension versus normotensive controls without familial hypertension. Normotensives with familial hypertension had WBC-Na and RBC-Na that were not significantly different from those in essential hypertensives. RBC-K was not significantly different between normotensives with familial hypertension, normotensives without familial hypertension and essential hypertensives. WBC-K was not significantly different between normotensives with familial hypertension and essential hypertensives. Normotensives with familial hypertension had significantly higher WBC-K than normotensives without familial hypertension and essential hypertensives. Correlations that were significant in the combined normotensive-hypertensive group include: (i) The direct relationship between blood pressure (systolic, diastolic and mean) and RBC-Na and also WBC-Na. (ii) The inverse relationship between blood pressure (diastolic and mean) and RBC-K and WBC-K. (iii) The direct relationship between body mass index and WBC-Na and WBC-K. Correlations that were significant in the essential hypertensive group include: (i) The inverse relationship between blood pressure (diastolic and mean) and RBC-K and also WBC-K. (ii) The direct relationship between body mass index and WBC-Na. Most of these results are compatible with the hypothesis that sodium is involved in the pathogenesis of essential hypertension (AU)


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Masculino , Feminino , Constituição Corporal , Sódio/sangue , Sódio/metabolismo , Potássio/sangue , Potássio/metabolismo , Pressão Arterial , Hipertensão/etnologia , Jamaica , Células Sanguíneas/análise , Eletrólitos/sangue , Índice de Massa Corporal , Estudos Transversais
6.
West Indian med. j ; 37(2): 92-6, June 1988.
Artigo em Inglês | MedCarib | ID: med-11707

RESUMO

Red cell sodium and potassium content were measured in 24 black hypertensive patients while they were hypokalaemic on thiazide diuretic therapy and again after potassium supplements (48 meq elemental K+/day). Mean and diastolic blood pressure levels fell by 4.1-4.4 and 4.5-5.2 mm Hg respectively with potassium supplementation, while both urinary excretion of potassium and serum potassium rose. Urinary sodium excretion was unchanged. Red cell potasssium remained within the normal range but red cell sodium, initially high, fell with potassium therapy. This study confirms the importance of potassium supplementation where hypokalaemic results from diuretic therapy (AU)


Assuntos
Feminino , Humanos , Masculino , Pressão Arterial/efeitos dos fármacos , Eritrócitos/análise , Hipertensão/tratamento farmacológico , Potássio/uso terapêutico , Sódio/sangue , Bendroflumetiazida/efeitos adversos , Negro ou Afro-Americano , Quimioterapia Combinada , Hipopotassemia/induzido quimicamente , Potássio/sangue , Jamaica
7.
Kingston; 1988. ix, 184 p. tab.
Tese em Inglês | MedCarib | ID: med-13766

RESUMO

The pathogenesis of the hypertension in pre-eclampsia, although obscure, has been related by many authorities to excessive retention. However, there are very few documented records of measurements of intracellular ionic levels and there is no concensus as to whether the levels are indeed elevated. In this thesis, a study of the leucocyte and erythrocyte sodium and potassium contents and blood pressures of two groups of pre-eclamptic primigravidae is presented. In both controls and patients who had or developed pre-eclampsia, leucocyte or erythrocyte sodium content increased with gestational age, peaking just before term and falling post partum. The potassium levels displayed the opposite pattern. These changes were of greater magnitude in patients with pre-eclampsia and were more pronounced in the leucocytes. The changes in blood pressure mirrored those in leucocyte sodium in both pre-eclamptics and controls. These data suggest that the excessive blood pressure changes in pre-eclampsia might be related to the changes in cell ionic content (AU)


Assuntos
Humanos , Gravidez , Adolescente , Adulto , Feminino , Sódio/sangue , Sódio/metabolismo , Eritrócitos/metabolismo , Pressão Arterial , Pré-Eclâmpsia , Potássio/metabolismo , Hipertensão , Jamaica
8.
Tese em Inglês | MedCarib | ID: med-15394

RESUMO

The bark of the cashew tree, Anacardium occidentale, is known to exert various therapeutic effects in the folklore medicine. However, there is little exiperimental evidence to substantiate these claims. West, Garvey and Ling in 1973 reported hypotensive action. Present investigations were carried out to find the possible mode of its hypotensive and anticurare effects. It is now well known that most of the clinically used antihypertensive drugs exert their pharmacotherapeutic effect via a common mode of action in spite of their different origins. Bhargava proposed that the central adrenergic, dopaminergic, cholinergic and tryptaminergic mechanisms in the central nervous system regulate the cardiovascular system, but the existence of such a central mechanism does not rule out the possibility of a peripheral component in the antihypertensive action of the drugs. The pathways followed by the central adrenergic and serotonergic nerves in the central nervous sytem are well suited for the regulation of the blood pressure. Most animals which received Anacardium occindentale showed an initial hypotensive response following the administration. This was marked and was not influenced by several experimental procedure or the drug pretreatments. The delayed hypotensive response occurred in most of the animals between 60 to 120 min after its administration and once set, remained below the basal level all throughout the duration of the experiment. The experimental manoeuvres and drug designs did not influence the delayed hypotensive response. The hypotensive action occurred in rats, cats and dogs and did not show any initial rise in blood pressure. (au)


Assuntos
Gatos , Ratos , 21003 , Hipertensão , Relaxamento Muscular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Respiração/efeitos dos fármacos , Potássio/farmacocinética , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Medicina Tradicional
9.
West Indian med. j ; 35(Suppl): 28, April 1986.
Artigo em Inglês | MedCarib | ID: med-5959

RESUMO

Hypokalaemia is a frequent accompaniment of chronic diuretic therapy of hypertension. It is associated with an increased risk of cardiac arrhythmias as well as several biochemical abnormalities. Potassium supplementation produces a rise in serum potassium level and a fall in the mean blood pressure. The mechanisms underlying the changes in blood pressure with changes in body potassium status are ill understood but might involve changes in cell electrolytes. We therefore measured red cell sodium and potassium content in hypertensive patients during diuretic-induced hypokalaemia and after potassium supplementation. Eleven patients were treated with bendrofluazide (10 mg daily) for a monthe before measurements of serum and urine potassium, blood glucose level, uric acid and red cell sodium and potassium concentrations were made. Potassium chloride (60 mmol/day) was added for another month and the same measurements repeated. Red cell electrolyte content was measured by flame photometry after isolating the cells by density centrifugation. Mean blood pressure fell (103 ñ 3 to 95 ñ 3mm hg, p<0.005) with the change in serum potassium level from 3.1 ñ 0.1 to 4.1 ñ 0.3 meq/l(p<0.05). Red cell sodium content fell from 13.8 ñ 1.4 to 10.8 ñ 1.3 mmol Na/l RBC while potassium content was unchanged 90.7 ñ 8.6 vs 81.1 ñ 7.2 (p>0.10). Insignificant reductions in blood glucose and uric acid levels occurred. The fall in cell sodium concentration could contribute to the fall in blood pressure if similar changes occurred in vascular smooth muscle cells. Potassium supplementation enhance blood pressure control in hypokalaemic hypertensives (AU)


Assuntos
Humanos , Hipopotassemia/tratamento farmacológico , Potássio , Bendroflumetiazida/administração & dosagem , Hipertensão/tratamento farmacológico
10.
West Indian med. j ; 34(suppl): 41, 1985.
Artigo em Inglês | MedCarib | ID: med-6683

RESUMO

A derangement in cell sodium homeostasis has been reputed to be the cause of primary hypertension in man. This hypothesis is supported by findings of raised intracellular sodium and suppressed sodium pump activity. These findings, however, are not universal. These experiments were designed to measure red cell sodium and potassium content and sodium transport activity as well as to define the role of plasma in these transport activities. Twelve hypertensives and 27 normotensive controls were subjected to venipuncture. Red cells were separated from plasma and the cellular content of sodium and potassium was measured. Na efflux from loaded cells was used to measure sodium pump activity and contransport. Red cell sodium content was slightly higher in hypertensive patients (10.4ñ2.8 vs 8.7ñ2.1 mMOl/l RBC, p<.05). Red cell potassium was the same in both groups (110ñ7 vs 113ñ8 mMOl/l RBC). Ouabain-sensitive sodium efflux, a measure of sodium pump activity, was the same in hypertensives and normotensives (6.69ñ2.57 vs 6.57ñ2.34 mMol/l /RBC/h). Plasma incubation produced an across-the-board reduction in sodium transport activities. Ouabain-sensitive efflux was 5.79ñ3.05 vs 4.23ñ2.66, and contransport, 0.57ñ0.28 vs 0.63ñ0.27 mMol/l RBC/h in hypertensives and normotensives respectively. We conclude that red cell sodium homeostasis is virtually identical in hypertensives and normotensives and that a circulating inhibitor is present to the same degree in both their plasmas. These data do not support the hypothesis that essential hypertension is causally associated with derangements of cell sodium metabolism (AU)


Assuntos
Humanos , Masculino , Feminino , Eritrócitos/metabolismo , Sódio/metabolismo , Hipertensão/etiologia , Hipertensão/metabolismo , Homeostase , Potássio
11.
Br Med J ; 283(6283): 5-7, July 4, 1981.
Artigo em Inglês | MedCarib | ID: med-12580

RESUMO

Leucocyte sodium and potassium content and concentrations were measured along with ouabain-sensitive and ouabain-insensitive rate constants for sodium efflux in 14 controls and 20 black patients with essential hypertension. Leucocyte sodium content was significantly increased in the patients (mean 101.1 ñ 7.8 mmol/kg dry solids v 74.5 ñ 7.6 mmol/kg dry solids; p<0.05), whereas the rate constants for sodium efflux were not significantly reduced. There was no difference between the two groups in cell potassium values. The increase in leucocyte sodium content in the presence of normal rate constants for sodium efflux suggests an increase in membrane permeability to sodium, which might be important in the pathogenesis of essential hypertension. (AU)


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Hipertensão/sangue , Leucócitos/metabolismo , Sódio/sangue , Potássio/sangue , Transporte Biológico Ativo , Jamaica , Cinética , Água/metabolismo
12.
West Indian med. j ; 30(1): 30-3, Mar. 1981.
Artigo em Inglês | MedCarib | ID: med-11357

RESUMO

The first report of the renin status of Jamaican hypertensives is presented. A profile of the hypertensive population showed that 24 percent had high renin levels, 45 percent normal renin levels, and 31 percent low renin levels. There was no relationship between patients with high renin levels and those with ischaemmic heart disease. Patients with malignant hypertension and those with renal disease had the highest measured renin values. Some of the factors influencing renin output were examined (AU)


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão/sangue , Renina/sangue , Potássio/sangue , Jamaica
14.
West Indian med. j ; 29(2): 117-22, June 1980.
Artigo em Inglês | MedCarib | ID: med-11299

RESUMO

Bananas are known to have a high K+ content. The bioavailability of the K+ in bananas was compared with that in Slow-K tablets in 5 normal subjects. 24-hr urinary K+ excretion was assumed to be an index of K+ absorbed from the gatro-intestinal tract. The results indicate that the K+ in bananasis available, since 24-hr K+ excretion rose significantly during the period of banana consumption. The rise in K+ excretion while taking Slow-K was however, greater, the difference between the two being highly significant (p<0.01). The possible reasons for this difference are discussed. It is suggested that bananas may be a useful and safer alternative to Slow-K for K+ supplementation in patients in whom the extra calories are not contraindicated (AU)


Assuntos
Adulto , Humanos , Masculino , Frutas , Potássio/urina , Disponibilidade Biológica , Creatinina/urina , Preparações de Ação Retardada , Diuréticos/efeitos adversos , Deficiência de Potássio/induzido quimicamente , Deficiência de Potássio/terapia , Potássio/administração & dosagem , Potássio/metabolismo , Sódio/urina
15.
Kingston; s.n; June 1980. 388 p. tab.
Tese em Inglês | MedCarib | ID: med-13633

RESUMO

There is a need for data on cellular electrolytes and sodium pump activity in many models of hypertension because it has become evident that if sodium is involved in hypertension, it is at the cellular level that it is important. This study was designed to measure leucocyte sodium, potassium, and rate constants for sodium efflux, total and ouabain insensitive, in animal and human hypertension. In Goldblatt-2-kidney hypertension, leucocyte electrolytes and rate constants were undisturbed. In Goldblatt-1-kidney hypertension, leucocyte, sodium content unchanged, potassium concentration was depressed, and the rate constant for total sodium efflux was lower. The passive efflux represented by the ouabain insensitive efflux, remained the same. In Goldblatt-1-kidney rats drinking 1 percent saline leucocyte sodium content fell while rate constant for total sodium efflux was increased. Ouabain insensitive efflux was unchanged. In DOCA hypertension, leucocyte sodium content was marginally elevated while the rate constant for total sodium efflux was also increased. Passive efflux was unchanged. Leucocytes from patients with essential hypertension had a high sodium content and concentration, and normal potassium content. Potassium concentration was depressed because of a higher cell water. Total sodium efflux rate constant was unchanged as was ouabain insensitive efflux. In pre-eclampsia, leucocyte sodium content and concentration were elevated while potassium content and concentration were depressed. The rate constant for total sodium efflux was lower while ouabain insensitive efflux was the same. These abnormalities disappeared six months after delivery. These findings are consistent with a hypothesis that cellular sodium is important in the pathogenesis of hypertension, but that there are at least two schemata for its involvement in the various models. (AU)


Assuntos
Humanos , Ratos , Hipertensão , Sódio/metabolismo , Hipertensão/induzido quimicamente , Hipertensão Renovascular/induzido quimicamente , Pré-Eclâmpsia/metabolismo , Potássio/metabolismo , Ouabaína , Leucócitos/metabolismo , Eletrólitos/metabolismo
16.
Am J Clin Nutr ; 33(3): 617-20, Mar. 1980.
Artigo em Inglês | MedCarib | ID: med-15786

RESUMO

Zinc supplementation of children who were just completing a period of rapid "catch-up" growth during recovery from severe malnutrition was found to stimulate sodium transport in their leucocytes. These results suggest that zinc status should be studied in the large number of serious illness now known or thought to be associated with impaired sodium transport.(AU)


Assuntos
Humanos , Lactente , Desnutrição Proteico-Calórica/metabolismo , Sódio/sangue , Zinco/uso terapêutico , Transporte Biológico/efeitos dos fármacos , Potássio/sangue , Desnutrição Proteico-Calórica/dietoterapia , Zinco/sangue
17.
Pediatr Res ; 12(7): 767-70, Jul. 1978.
Artigo em Inglês | MedCarib | ID: med-9917

RESUMO

Leukocyte potassium has been measured in normal subjects and in malnourished children with and without edema both on admission and during recovery. In nonedematous malnourished children the potassium content was low (328mmol/kg dry solids) and took 2-3 weeks of rehabilitation to return to normal (374 mmol/kg dry solids). Leukocytes from edematous children had normal intracellular potassium values. However, 5 days on a maintenance diet reduced the intracellular potassium in the children with kwashiorkor to a value similar to that found in marasmus. Plasma potassium was significantly lower in kwashiorkor (3.43) than in marasmus (4.74). The relationship between external potassium and internal potassium in normal leukocytes was measured (fig.1) and the values found severe malnutrition compared with normal. It was found that in nonedematous malnutrition intracellular potassium was low compared to the predicted value, whereas in kwashiorkor, although the mean values were normal, no relationship between external potassium and intracellular potassium could be demonstrated. It is concluded that in the leukocyte malnutrition alters either the passive permeability of the membrane to potassium or the active transport of potassium of both.(AU)


Assuntos
Humanos , Lactente , Leucócitos/análise , Potássio/sangue , Desnutrição Proteico-Calórica/sangue , Transporte Biológico , Líquido Intracelular/análise , Kwashiorkor/sangue , Potássio/metabolismo , Espaço Extracelular/análise
18.
Kingston; s.n; Feb. 1978. 94 p. tab.
Tese em Inglês | MedCarib | ID: med-13709

RESUMO

There is indirect evidence that infants' bottle feeds in Jamaica may be overdialuted. Infantile gastroenteritis is frequent and it has been suggested that a casual factor may be the inadequate sterilisation of bottles. The aim of ths study was to determine the nutrient contents of bottle feeds of Kingston infants aged 6-23 months and to assess the extent of bacterial contamination. The feeds analysed were either milk based or porridges. 151 samples were collected from three clinics and analysed for (1) protein, by micro-Kjeldahl method; (2) energy by comb calorimetry and (3) sodium and potassium by flame photometry. 101 samples were analyses for coliform bacterial contamination by use of Oxoid dip slides. The majority of the samples had protein contents which were within the normal range. The total solids and energy contents of the milk feeds were frequently high because of sugar added in preparation but the energy and solid contents of porridges were low. The milk feeds had normal sodium and low potassium concentrations, but porridges had high sodium concentrations due to addition of salt during preparation. 64 percent of the samples were highly contaminated by coliform baceria, although the majority of mothers reported having adequate facilities for proper feed preparation and sterilisation. It could be concluded that most mothers who attend child welfare clinics are preparing milk formulae with the correct protein content but with high energy content, porridges which are too dilute and have too much salt added, and bottle feeds are generally not sterile (Summary)


Assuntos
Humanos , Lactente , Apoio Nutricional , Bactérias/análise , Avaliação Nutricional , Esterilização , Gastroenterite/etiologia , Sódio na Dieta/análise , Potássio/análise , Proteínas na Dieta/análise , Dieta , Contaminação de Alimentos/análise , Jamaica , Grão Comestível/análise , /análise
19.
Am J Clin Nutr ; 30(9): 1478-81, Sept. 1977.
Artigo em Inglês | MedCarib | ID: med-10380

RESUMO

Intracellular electrolytes and sodium transport were measured in leukocytes obtained from malnourished children. In the presence of edema, leukocyte sodium and potassium were raised. The total flux and the glycoside-sensitive portion were increased. Loss of edema was associated with reductions in all these measurements. In marasmus, glycoside-sensitive sodium efflux was reduced compared to recovered values. Sodium was increased and potassium reduced. It is concluded that at least two defects in sodium transport may occur in protein energy malnutrition, an increased passive permeability in kwashiorkor and a reduced active transport for sodium in marasmus. (AU)


Assuntos
Humanos , Criança , Leucócitos/metabolismo , Potássio/sangue , Desnutrição Proteico-Calórica/sangue , Sódio/sangue , Transporte Biológico/efeitos dos fármacos , Edema/complicações , Glicosídeos/farmacocinética , Kwashiorkor/sangue , Desnutrição Proteico-Calórica/complicações , Desnutrição Proteico-Calórica/dietoterapia
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