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1.
Indian J Clin Biochem ; 30(2): 180-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25883426

RESUMEN

It is known that there is a significant interplay of insulin resistance, oxidative stress, dyslipidemia, and inflammation in type 2 diabetes mellitus (T2DM). The study was undertaken to investigate the effect of turmeric as an adjuvant to anti-diabetic therapy. Sixty diabetic subjects on metformin therapy were recruited and randomized into two groups (30 each). Group I received standard metformin treatment while group II was on standard metformin therapy with turmeric (2 g) supplements for 4 weeks. The biochemical parameters were assessed at the time of recruitment for study and after 4 weeks of treatment. Turmeric supplementation in metformin treated type 2 diabetic patient significantly decreased fasting glucose (95 ± 11.4 mg/dl, P < 0.001) and HbA1c levels (7.4 ± 0.9 %, P < 0.05). Turmeric administered group showed reduction in lipid peroxidation, MDA (0.51 ± 0.11 µmol/l, P < 0.05) and enhanced total antioxidant status (511 ± 70 µmol/l, P < 0.05). Turmeric also exhibited beneficial effects on dyslipidemia LDL cholesterol (113.2 ± 15.3 mg/dl, P < 0.01), non HDL cholesterol (138.3 ± 12.1 mg/dl, P < 0.05) and LDL/HDL ratio (3.01 ± 0.61, P < 0.01) and reduced inflammatory marker, hsCRP (3.4 ± 2.0 mg/dl, P < 0.05). Turmeric supplementation as an adjuvant to T2DM on metformin treatment had a beneficial effect on blood glucose, oxidative stress and inflammation.

2.
Eur J Clin Nutr ; 65(6): 690-5, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21386858

RESUMEN

BACKGROUND/OBJECTIVES: Plasma leptin and adiponectin, and membrane phospholipid fatty acid composition are implicated into the mechanism of insulin resistance but no clear pattern has emerged. Hence, this study examined these variables in subjects presenting to the diabetic clinic for a diagnostic glucose tolerance test. SUBJECTS/METHODS: Body composition, glucose, glycated hemoglobin, insulin, leptin, adiponectin, and red cell and plasma phospholipid fatty acids were assessed from 42 normal and 28 impaired glucose tolerant subjects. Insulin sensitivity was determined by homeostatic model assessment. RESULTS: The plasma phosphatidylcholine fatty acid composition of the impaired glucose tolerant subjects was similar to that of normal subjects. However, the impaired glucose tolerant subjects had significantly lower linoleic (P<0.05), eicosapentaenoic (P<0.05) and docosahexaenoic (P<0.01) acids in the red cell phosphatidylcholine and phosphatidylethanolamine compared with the normal subjects. Moreover, red cell phosphatidylcholine docosahexaenoic acid correlated positively with adiponectin (r=0.290, P<0.05) but negatively with leptin (r=-0.252, P<0.05), insulin (r=-0.335, P<0.01) and insulin resistance (r=-0.322, P<0.01). Plasma triglycerides, leptin and glucose combined predicted about 60% of variation in insulin level whereas insulin was the only component that predicted the membrane fatty acids. CONCLUSIONS: We postulate that membrane phospholipids fatty acids have an indirect role in determining insulin concentration but insulin has a major role in determining membrane fatty acid composition.


Asunto(s)
Adipoquinas/sangre , Membrana Celular/metabolismo , Eritrocitos/metabolismo , Ácidos Grasos/sangre , Intolerancia a la Glucosa/sangre , Resistencia a la Insulina , Insulina/sangre , Adiponectina/sangre , Adulto , Glucemia/metabolismo , Ácidos Docosahexaenoicos/sangre , Ácidos Grasos Omega-3/sangre , Femenino , Glicerofosfolípidos/sangre , Humanos , Leptina/sangre , Ácido Linoleico/sangre , Masculino , Persona de Mediana Edad , Triglicéridos/sangre
3.
Thorax ; 62(11): 1003-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17526677

RESUMEN

BACKGROUND: As well as its role in the regulation of calcium metabolism, vitamin D is an immunoregulatory hormone. Epidemiological evidence also suggests a link between vitamin D deficiency and tuberculosis (TB). A study was undertaken to examine serum vitamin D concentrations before treatment in patients with active TB and their contacts from the same ethnic and social background and to investigate the relative contributions of diet and sunlight exposure. METHODS: Serum vitamin D concentrations were measured before treatment in 178 patients with active TB and 130 healthy contacts. The prevalence of vitamin D deficiency and its relation to skin colour, month of estimation and TB diagnosis were determined. 35 patients and 35 frequency-matched contacts completed dietary and sun exposure questionnaires to determine the relative contribution of these to serum vitamin D concentrations. RESULTS: There was a statistically significant difference in serum vitamin D concentrations between patients and contacts (20.1 vs 30.8 nmol/l, 95% CI 7.1 to 14.3; p<0.001) and significantly more patients had severely deficient concentrations (<21 nmol/l) than controls (114/178 (64%) vs 40/130 (31%), p<0.001). There was no association between serum concentrations of vitamin D and skin pigmentation. The healthy contacts showed a predictable seasonal pattern, rising to peak concentrations in the summer months, but this response was absent in patients with TB. Dietary intake was the same in both patients with TB and contacts matched for age, sex and skin colour, but patients with TB displayed a stronger correlation between serum vitamin D concentrations and dietary intake (r = 0.42, p = 0.016) than controls (r = 0.13, p>0.1). There was no difference in sunlight exposure between the groups. CONCLUSIONS: Patients with active TB have lower serum vitamin D concentrations than contacts from similar ethnic and social backgrounds and with comparable dietary intake and sun exposure, and do not show the expected seasonal variation. These observations indicate that other factors are contributing to vitamin D deficiency in patients with TB and suggest abnormal handling of this vitamin.


Asunto(s)
Calcifediol/deficiencia , Dieta , Pigmentación de la Piel/fisiología , Luz Solar , Tuberculosis Pulmonar/etiología , Deficiencia de Vitamina D/complicaciones , Adolescente , Adulto , Anciano , Niño , Preescolar , Suplementos Dietéticos , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Recurrencia , Estaciones del Año , Tuberculosis Pulmonar/sangre , Vitamina D/administración & dosificación , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/dietoterapia
4.
Bioorg Med Chem Lett ; 16(20): 5468-71, 2006 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-16945534
5.
J Indian Med Assoc ; 104(2): 63-6, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16856583

RESUMEN

In severe form of tetanus, even with maximum dose of muscle relaxants, spasms and apnoeic spells may persist and that may be life-threatening. The aim of this study was to assess the effect of neuroparalysing the patients and then providing ventilatory support in bringing about their recovery. Forty-nine adult patients of severe tetanus (Ablett's grade IIIA--6 patients and Ablett's grade IIIB--43 patients) were studied during the period from April, 1993 to February, 1996. Mean period of onset ie, period from trismus to first spasm, in these patients was 24 hours. Patients were neuroparalysed with a bolus dose of 2-4 mg of pancuronium followed by a continuous infusion of 1-2 mg/hour and simultaneously supported with mechanical ventilation until spasms subsided. Fourteen patients (28.6%) survived and rest died. Mean duration of ventilatory support on survived patients was 14.4 days. The commonest complication encountered during ventilatory support was respiratory tract infection observed in 36 patients (73.5%). Commonest cause of death was autonomic imbalance encountered in 15 patients (30.6%). Treatment of choice in severe tetanus should be neuroparalytic ventilatory support. With use of new generation ventilators and better intensive care facility, death in severe tetanus is likely to be very less.


Asunto(s)
Pancuronio/uso terapéutico , Respiración Artificial/métodos , Parálisis Respiratoria/inducido químicamente , Espasmo/tratamiento farmacológico , Tétanos/tratamiento farmacológico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Tétanos/complicaciones
6.
Eur J Clin Nutr ; 58(12): 1661-5, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15305177

RESUMEN

OBJECTIVE: To investigate the effects of a 400 mg acute oral calcium dose on PTH and bone resorption markers in a young, healthy population. DESIGN: Fasting serum parathyroid hormone (PTH), C-telopeptides (CTX), total calcium (Ca), albumin and urinary calcium/creatinine ratio (uCa/Cr) were measured on two separate days: one before and the other 10 h after oral administration of 400 mg calcium. Serum 25-hydroxy vitamin D (25-OHD) status was assessed at baseline. Dietary calcium intake was assessed using a food frequency questionnaire (FFQ). SUBJECTS: A total of 32 healthy, young adults (17 female, 15 male; mean+/-s.e.m. age: 21+/-1 y) took part in this study. Their mean (s.e.m.) calcium intake was 1125 (+/-56) mg/day. INTERVENTION: Effervescent Sandocal 400 tablets dissolved in water. RESULTS: After the calcium challenge, mean Ca and uCa/Cr ratio increased significantly, and both PTH and CTX concentrations were significantly lower. Multiple regression analysis showed no relationship between the response to the 400 mg load and previous dietary calcium intake (as assessed by FFQ) or serum 25-OHD. CONCLUSION: We have shown that in a young, healthy population, 400 mg oral calcium can inhibit bone resorption (as measured by serum CTX) and PTH, and this appears to be independent of previous dietary calcium intake and vitamin D status.


Asunto(s)
Resorción Ósea , Calcio/administración & dosificación , Colágeno/sangre , Hormona Paratiroidea/sangre , Péptidos/sangre , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Administración Oral , Adolescente , Adulto , Calcio/metabolismo , Calcio/orina , Calcio de la Dieta/administración & dosificación , Colágeno Tipo I , Creatinina/orina , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
7.
Osteoporos Int ; 12(4): 319-25, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11420782

RESUMEN

Vitamin D status is known to be an important determinant of bone mineral density (BMD). There is a significant seasonal variation in serum vitamin D, and some studies have reported an associated seasonal variation in BMD. The present study was devised to investigate whether a seasonal variation in BMD could be detected in healthy normal subjects, along with associated variations in serum parathyroid hormone (PTH), intestinal calcium absorption and biochemical markers of bone turnover. A second aim was to investigate whether, if such variations were identified, they could be suppressed by vitamin D supplementation. The subjects were 70 healthy female volunteers (mean age 47.2 years, range 24-70 years) recruited into a double-masked crossover study and followed over 2 years. During the first year 35 subjects received a daily oral supplement containing 800 IU (20 micrograms) cholecalciferol (group 1) and 35 subjects received a placebo preparation (group 2). During the second year the treatment each group received was reversed. Lumbar spine (L1-L4), left proximal femur and total body BMD were measured by DXA at 3-month intervals. Serum 25-hydroxyvitamin D (25-OHD), serum PTH, bone markers (bone-specific ALP (BSAP) and urinary crosslinks (DYPD/creatinine)) and calcium absorption were also measured at each visit. Cholecalciferol treatment increased serum 25-OHD by 25.4 nmol/l (p < 0.001), while a reciprocal decrease in serum PTH of 6.6 ng/l (p = 0.011) was seen in subjects in the lowest quartile of baseline serum 25-OHD. The treatment had no significant effect on spine, femur or total body BMD, calcium absorption or bone markers. When Fourier analysis was used to analyze the data for seasonal effect (defined as twice the amplitude of the 1-year period variation) a highly significant effect for 25-OHD of 18 nmol/l (p < 0.001) was found. However, no effect was found for BMD, PTH, calcium absorption or bone markers. The analysis set a 95% confidence limit to the seasonal effect of less than 0.6% for spine, total hip and total body BMD. It was concluded that in the population of healthy women studied there was no evidence of seasonal variation in spine, femur or total body BMD, serum PTH, calcium absorption or bone markers. Vitamin D supplementation was found to have no effect on BMD.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Suplementos Dietéticos , Estaciones del Año , Vitamina D/análogos & derivados , Vitamina D/farmacología , Adulto , Anciano , Biomarcadores/análisis , Estudios Cruzados , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Vértebras Lumbares/fisiología , Menopausia/fisiología , Persona de Mediana Edad , Vitamina D/sangre
8.
J Bone Miner Res ; 15(11): 2276-83, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11092410

RESUMEN

Vitamin D supplementation, when given with calcium, has been shown to increase bone mineral density (BMD) and reduce the incidence of hip fracture in elderly subjects. Despite its widespread use, the benefits of vitamin D supplementation in younger women and as a single agent are less clear. We performed a randomized co-twin, placebo-controlled, double-blind trial over 2 years to measure the effect of vitamin D3 supplementation on bone density and bone metabolism in young postmenopausal women. Seventy-nine monozygotic (MZ) twin pairs (mean age, 58.7 years; range, 47-70 years) were recruited. For each twin pair, one was randomized to 800 IU cholecalciferol/day for 2 years and the other was randomized to placebo. BMD was measured at the spine and hip and heel ultrasound at baseline, 12, 18, and 24 months. Samples were collected at 0, 3, and 6 months to measure serum calcium, 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), osteocalcin, and urinary deoxypyridinoline (DPD). In total, 64 pairs completed the study. No differences in baseline characteristics were seen between the groups. At 6 months, the treatment group had an increase in serum vitamin D [mean +/- SEM intrapair difference, 14.1+/-2.4 microg/liter (p < 0.001)]. There were no significant differences in other serum measurements or bone markers at 3 months or 6 months. At 24 months, no significant treatment effect was seen on BMD or calcaneal ultrasound change within pairs. Subanalysis of treatment response by vitamin D receptor (VDR) genotype revealed no significant difference in effect on BMD variables with treatment. On the basis of these results, vitamin D supplementation, on its own, cannot be recommended routinely as an osteoporosis prevention for healthy postmenopausal women with normal vitamin D levels under the age of 70 years.


Asunto(s)
Huesos/metabolismo , Osteoporosis Posmenopáusica/prevención & control , Vitamina D/farmacología , Anciano , Densidad Ósea , Huesos/efectos de los fármacos , Calcáneo/diagnóstico por imagen , Calcio/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/metabolismo , Receptores de Calcitriol/genética , Gemelos Monocigóticos , Ultrasonografía
9.
J Commun Dis ; 32(4): 240-6, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11668934

RESUMEN

Anthrax is a zoonotic illness caused by Bacillus anthracis. Sporadic cases continue to be reported from many parts of the world. From India, both sporadic cases and outbreaks are being reported regularly. The Union Territory of Pondicherry (a former French colony) lies on the coast of Bay of Bengal, where the incidence of anthrax is on the rise with 28 cases being detected in the year 1999 and 2000 alone. So far, about 34 human cases have been encountered in this region. Recently, an increase in the number of anthrax cases has been noted in veterinary and human practice in this area. Most cases have occurred in agricultural labourers who gave history of handling animal meat or skin of infected animals. The meningitic form of the disease has a very bad prognosis. Patients with this form of disease died despite treatment with high dose penicillin. The typical bacilli were seen in the CSF in all cases of anthrax meningitis and was diagnostic of the condition. The cutaneous form of illness had a benign course and responded favourably to penicillin treatment. Awareness among clinicians and mandatory reporting of cases to public health departments along with public education will help control morbidity and mortality due to anthrax. Effective immunization of animals is the other important control measure for anthrax.


Asunto(s)
Carbunco/prevención & control , Penicilinas/uso terapéutico , Zoonosis , Animales , Carbunco/tratamiento farmacológico , Carbunco/epidemiología , Carbunco/transmisión , Brotes de Enfermedades/prevención & control , Contaminación de Alimentos , Humanos , Incidencia , India/epidemiología , Notificación Obligatoria , Pronóstico , Salud Pública
10.
Int J Clin Pract ; 53(7): 540-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10692741

RESUMEN

Nutritional factors are important but correctable factors in the pathogenesis of osteoporosis. The rate of bone loss in the elderly can be reduced and the peak bone mass in the young can possibly be increased by dietary manipulation, thereby reducing the risk of fracture. Dietary manipulation likely to be of benefit are increased calcium intake, increased vitamin D intake, moderate reduction in intake of salt protein, caffeine and phosphate and increased intake of potassium and magnesium. The possible mechanisms by which these dietary factors influence bone metabolism are discussed.


Asunto(s)
Osteoporosis , Factores de Edad , Densidad Ósea , Calcio/metabolismo , Suplementos Dietéticos , Femenino , Humanos , Masculino , Estado Nutricional , Osteoporosis/dietoterapia , Osteoporosis/etiología , Osteoporosis/metabolismo , Factores de Riesgo , Sodio en la Dieta/administración & dosificación , Sodio en la Dieta/metabolismo , Vitamina D/administración & dosificación , Vitamina D/metabolismo
11.
Biophys J ; 72(4): 1900-7, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9083693

RESUMEN

The green fluorescent protein (GFP) was used as a noninvasive probe to quantify the rheological properties of cell cytoplasm. GFP mutant S65T was purified from recombinant bacteria for solution studies, and expressed in CHO cell cytoplasm. GFP-S65T was brightly fluorescent in solution (lambda ex 492 nm, lambda em 509 nm) with a lifetime of 2.9 ns and a rotational correlation time (tc) of 20 ns. Recovery of GFP fluorescence after photobleaching was complete with a half-time (t1/2) in aqueous saline of 30 +/- 2 ms (5-micron diameter spot), giving a diffusion coefficient of 8.7 x 10(-7) cm2/s. The t1/2 was proportional to solution viscosity and was dependent on spot diameter. In contrast to fluorescein. GFP photobleaching efficiency was not affected by solution O2 content, triplet state quenchers, singlet oxygen scavengers, and general radical quenchers. In solutions of higher viscosity, an additional, rapid GFP recovery process was detected and ascribed to reversible photobleaching. The t1/2 for reversible photobleaching was 1.5-5.5 ms (relative viscosity 5-250), was independent of spot diameter, and was unaffected by O2 or quenchers. In cell cytoplasm, time-resolved microfluorimetry indicated a GFP lifetime of 2.6 ns and a tc of 36 +/- 3 ns, giving a relative viscosity (cytoplasm versus water) of 1.5. Photobleaching recovery of GFP in cytoplasm was 82 +/- 2% complete with a t1/2 of 83 +/- 6 ms, giving a relative viscosity of 3.2. GFP translational diffusion increased 4.7-fold as cells swelled from a relative volume of 0.5 to 2. Taken together with measurements of GFP translation and rotation in aqueous dextran solutions, the data in cytoplasm support the view that the primary barrier to GFP diffusion is collisional interactions between GFP and macromolecular solutes.


Asunto(s)
Citoplasma/fisiología , Proteínas Luminiscentes/química , Animales , Difusión , Escherichia coli/genética , Fluoresceína , Fluoresceínas/metabolismo , Polarización de Fluorescencia , Proteínas Fluorescentes Verdes , Cinética , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/aislamiento & purificación , Proteínas Luminiscentes/metabolismo , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes de Fusión , Escifozoos/química , Espectrometría de Fluorescencia , Transfección/genética , Viscosidad
12.
Diabetes Care ; 18(7): 1001-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7555530

RESUMEN

OBJECTIVE: To examine the factors that determine the blood pressure response to enalapril and nifedipine monotherapy in the treatment of hypertension associated with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS: After a 6-week placebo baseline period, 102 hypertensive NIDDM patients were randomly assigned, double-blindly, to treatment with nifedipine retard (slow release) (n = 52) or enalapril (n = 50). The daily dosage of enalapril was increased, if required, from 10 to 20 to 40 mg and that of nifedipine from 40 to 60 to 80 mg at 4-week intervals during the 12-week titration period. Blood pressure, 24-h urinary albumin excretion (UAE), biochemical data, and serum angiotensin-converting enzyme (ACE) activity were measured at weeks -6, -4, 0, 4, 8, and 12. At week 0, venous blood was also sampled for baseline plasma atrial natriuretic peptide, renin, aldosterone, and serum insulin concentrations. RESULTS: At week 12, the mean daily dose of enalapril was 35 +/- 11.4 mg, and 27 (57%) patients were receiving the maximum daily dose of 40 mg. In the nifedipine group, the mean daily drug dose was 50 +/- 12.9 mg, and 4 (8%) were receiving the maximum daily dose of 80 mg. Despite a dose-dependent fall in the serum ACE activity in the enalapril group, the mean arterial pressure (MAP) was reduced by only 8 mmHg throughout the 12-week titration period compared to a decline of 15, 18, and 19 mmHg at weeks 0, 4, and 12, respectively, in the nifedipine group (P = 0.01 between groups). In the enalapril group, changes in MAP between weeks 0 and 12 correlated significantly with baseline plasma glucose (r = 0.45, P = 0.001) and aldosterone concentrations (r = -0.32, P = 0.02) and UAE (r = 0.3, P = 0.04). There was no statistically significant correlation between the changes in MAP and baseline plasma renin concentration. On multivariate analysis, the baseline renal function, glycemic control, and plasma aldosterone and serum insulin concentrations were all independently related to the changes in blood pressure in the enalapril-treated patients. No such statistical associations were observed in the nifedipine group. CONCLUSIONS: In hypertensive NIDDM patients, the activity of the renin-angiotensin-aldosterone system, the level of serum insulin, glycemic control, renal function, and proteinuria may be important determinants of the blood pressure response to ACE inhibition. Good glycemic control may optimize the antihypertensive efficacy of concomitant ACE inhibitor therapy.


Asunto(s)
Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Angiopatías Diabéticas/tratamiento farmacológico , Enalapril/uso terapéutico , Hipertensión/tratamiento farmacológico , Nifedipino/uso terapéutico , Albuminuria , Aldosterona/sangre , Factor Natriurético Atrial/sangre , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/fisiopatología , Diuréticos/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Furosemida/uso terapéutico , Hemoglobina Glucada/análisis , Humanos , Hipertensión/fisiopatología , Indapamida/uso terapéutico , Placebos , Potasio/sangre , Potasio/orina , Análisis de Regresión , Renina/sangre , Sodio/sangre , Sodio/orina , Factores de Tiempo
13.
Miner Electrolyte Metab ; 19(1): 36-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8345833

RESUMEN

Potassium depletion increases and potassium supplementation decreases urinary calcium excretion. To determine whether these experimental observations have any significance in healthy free living subjects, we measured 24 h urinary calcium, sodium, potassium and serum parathyroid hormone (PTH) in 142 healthy young (aged 18-40 years) female Chinese subjects. Sodium excretion and potassium excretion were positively correlated with calcium excretion (r = 0.494, p < 0.0001 and r = 0.181, p = 0.031, respectively). However stepwise multiple regression analysis showed that only urinary sodium excretion contributed to the excretion of calcium. We conclude that in free living subjects potassium intake has little effect on calcium excretion.


Asunto(s)
Calcio/orina , Potasio/administración & dosificación , Adolescente , Adulto , Femenino , Hong Kong , Humanos , Hormona Paratiroidea/sangre , Potasio/orina , Valores de Referencia , Sodio/orina
14.
BMJ ; 305(6860): 981-5, 1992 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-1458144

RESUMEN

OBJECTIVES: To compare the efficacy, safety, and tolerance of enalapril and nifedipine in hypertensive patients with non-insulin dependent diabetes. DESIGN: One year double blind follow up of patients randomly allocated to either enalapril or nifedipine with matching placebos for the alternative drug. SETTING: Metabolic Investigation Unit, Hong Kong. SUBJECTS: 102 patients were randomised: 52 to nifedipine and 50 to enalapril. At baseline 44 patients had normoalbuminuria, 36 microalbuminuria, and 22 macroalbuminuria. MAIN OUTCOME MEASURES: Blood pressure, albuminuria, and parameters of renal function and glycaemic control. RESULTS: In patients who completed one year's treatment the median dose required by the nifedipine group (n = 49) was 60 mg/day; seven (14%) required additional diuretics. Of 41 patients given enalapril, 37 required the maximum dose (40 mg/day) and 27 (76%) required diuretics. At one year mean arterial blood pressures were similar in both groups. Albuminuria fell by 54% in the enalapril group and 11% in the nifedipine group (p = 0.006). Fractional albumin clearance ratio fell by 47% in the enalapril group and increased by 3% in the nifedipine group (p = 0.009). Creatinine clearance fell similarly in both groups but plasma creatinine concentration was increased by 20% in the enalapril group versus 8% in the nifedipine group (p = 0.001). CONCLUSION: Patients taking enalapril often required diuretics to control blood pressure. Enalapril reduced proteinuria significantly more than nifedipine in the microalbuminuric and macroalbuminuric patients but increased plasma creatinine concentrations. Longer follow up is required to clarify the importance of enalapril's antiproteinuric effect.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Enalapril/uso terapéutico , Hipertensión/tratamiento farmacológico , Nifedipino/uso terapéutico , Albuminuria/etiología , Presión Sanguínea , Peso Corporal , Diabetes Mellitus Tipo 2/fisiopatología , Método Doble Ciego , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/fisiopatología , Riñón/fisiopatología , Masculino
15.
Osteoporos Int ; 2(4): 168-73, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1611221

RESUMEN

A randomized controlled trial was carried out to determine whether calcium supplementation and load-bearing exercise can increase or maintain bone mass in the elderly. Fifty Chinese women, aged 62-92 years, living in a hostel for the elderly in Hong Kong were randomized to enter one of four treatment groups: (I) calcium supplementation of 800 mg (as calcium lactate gluconate) daily; (II) load-bearing exercise four times a week plus a daily placebo tablet; (III) calcium supplementation daily and load-bearing exercise four times a week; (IV) a placebo tablet daily. The interventions went on for 10 months. The bone mineral density (BMD) was measured at three sites in the hip (femoral neck, Ward's triangle and intertrochanteric area) and the L2-4 level of the spine. The percentage change in BMD in 10 months was used as the main outcome measurement. The parathyroid hormone level and indices of bone metabolism were also measured before and after 10 months of intervention. The BMD at Ward's triangle and the intertrochanteric area increased significantly in subjects on calcium supplement (p less than 0.05), but there was no significant change at the spine and femoral neck. Exercise had no effect on bone loss at any site. However, the results of two-way analysis of variance showed a significant joint effect of calcium supplements and exercise at the femoral neck (p less than 0.05), but not at the other sites. The parathyroid hormone levels fell significantly in subjects on calcium supplements (p less than 0.01). Calcium supplement in the form of calcium lactate gluconate was adequately absorbed in elderly Chinese women with a calcium intake of less than 300 mg per day. It was effective in reducing bone loss at the hip, and there may be interaction effects with exercise in maintaining bone density.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcio de la Dieta/administración & dosificación , Ejercicio Físico , Osteoporosis/prevención & control , Anciano , Anciano de 80 o más Años , Femenino , Hong Kong/etnología , Humanos
16.
Clin Endocrinol (Oxf) ; 36(4): 375-81, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1424171

RESUMEN

OBJECTIVE: To study the age-related changes in bone density, serum parathyroid hormone, calcium absorption and other indices of calcium metabolism in Chinese women who habitually have a low calcium intake. DESIGN: Cross-sectional study. SUBJECTS: One hundred and fifty-six healthy Chinese women aged 20-83 years. None were on any medication or vitamin supplements. Subjects over the age of 60 years were all living in a hostel; younger subjects were nurses or subjects attending a family clinic for minor illnesses. MEASUREMENTS: Fasting blood and urine samples were collected for biochemical measurements and calcium absorption was measured using 45Ca by the method of Marshall and Nordin. Bone density was measured by dual energy X-ray densitometry (Norland X R20 X-ray bone densitometer) at the left hip and lumbar spine. Serum parathyroid hormone was measured by a chemiluminometric assay. RESULTS: Plasma ionized calcium concentration, alkaline phosphatase, bicarbonate, plasma creatinine and serum B2 microglobulin were significantly higher in the elderly than in the young, whereas plasma phosphate and the anion gap were higher in the young. Urinary excretion of calcium, phosphate and hydroxyproline were all higher in older women. Plasma parathyroid hormone concentration was positively correlated with age even after taking into account the decline in renal function (as indicated by the rise in B2 microglobulin (r = 0.506, P less than 0.001). Serum concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were not lower in the older women. Fractional calcium absorption from an oral load of radiolabelled calcium was significantly lower in the older women and 37% of the older women were below the 2.5 percentile found in the younger women. Bone density measured by dual energy X-ray densitometry was also significantly lower in the elderly. CONCLUSION: In Chinese women there is an increase in PTH and a decrease in calcium absorption with age in spite of the presence of normal vitamin D metabolites.


Asunto(s)
Envejecimiento/metabolismo , Densidad Ósea/fisiología , Huesos/metabolismo , Calcio/metabolismo , Hormona Paratiroidea/sangre , Absorción , Adulto , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/sangre , China , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad
17.
Clin Biochem ; 25(1): 15-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1312916

RESUMEN

A rapid and automated assay for inhibitors of Na+, K(+)-ATPase was developed by determining the amount of inorganic phosphorus (Pi) released by Na+,K(+)-ATPase in a centrifugal analyzer. This method avoids long incubation, strong acids and centrifugation as in the conventional manual method. The coefficients of variation of intra- and inter-assay at ouabain concentration 0.5 mumol/L were 1.0 and 1.4%, respectively. The method is quick, reproducible and easy compared with current techniques.


Asunto(s)
Riñón/enzimología , Proteínas/análisis , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Animales , Centrifugación , Química Clínica/métodos , Perros , Sangre Fetal , Humanos , Riñón/metabolismo , Ouabaína/farmacología , Fosfatos/análisis , Sensibilidad y Especificidad , , Proteína Inhibidora ATPasa
18.
Gen Comp Endocrinol ; 76(2): 261-6, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2591718

RESUMEN

An experiment was carried out to investigate the effect of a range of estradiol (E2) doses (0.1-6.5 micrograms/g body wt/day) on vitamin D metabolism and the plasma levels of growth hormone (GH) and prolactin (PRL) in the growing chick. Doses of 0.5-0.7 microgram/g E2, which are insufficient to raise the plasma calcium level, did induce an increase in growth rate, an increase in 25-hydroxyvitamin D 1 alpha-hydroxylase (1-hydroxylase) and 24-hydroxylase activities, and an increase in plasma GH level. These parameters leveled off or fell over the dose range 1-2 micrograms/g E2 but there was evidence of a second peak in 1-hydroxylase activity at 6 micrograms/g E2. At this high dose rate, the plasma Ca level rose to 8 mM, as it does in the laying hen; 24-hydroxylase activity, growth rate, and plasma GH and plasma PRL levels all decreased. It was concluded that the dose response to estrogen in the growing chick is not linear and, in the case of 1-hydroxylase activity, may even be biphasic.


Asunto(s)
Calcio/metabolismo , Pollos/crecimiento & desarrollo , Estrógenos/farmacología , Hormona del Crecimiento/sangre , Homeostasis/efectos de los fármacos , Prolactina/sangre , Animales , Relación Dosis-Respuesta a Droga , Masculino , Oxigenasas de Función Mixta/metabolismo , Vitamina D/metabolismo
19.
Acta Paediatr Scand ; 78(2): 303-6, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2929354

RESUMEN

Vitamin D deficiency is a common nutritional problem of weaning infants in many parts of the world. Hong Kong infants, who are fed with traditional rice-based weaning foods and live in crowded high rise flats, might be expected to suffer from this nutritional problem. Yet a study of 150 bottle fed infants revealed that the vitamin D intake from fortified milk and cereals was more than half of the recommended amount throughout the first 18 months and that the serum 25-OH vitamin D concentration of the infants at 18 months was normal. The effect of sunlight was also evident.


Asunto(s)
Alimentos Infantiles , Deficiencia de Vitamina D/epidemiología , Vitamina D/administración & dosificación , Calcifediol/sangre , Hong Kong , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Luz Solar
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