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Biomedical subjects

M G Karmarkar

Publications and source records attributed to M G Karmarkar.

At least 19 recordsLinked to original sources
PubMed1992

Nutrient interaction in relation to glycaemic and insulinaemic response.

Although it is known that protein, fat and fibre reduce the postprandial glycaemia following an oral carbohydrate load, the nature and extent of interaction of different nutrients with one another in this respect is not well understood. The present study was designed to explore systematically the glycaemic and insulinaemic response to glucose (G) alone, or in combination with one or more of the following: casein (CS), maize oil (MO), cellulose (CL) and pectin (P). Besides 100 g G, eleven isoenergetic and six isocarbohydrate meals were studied on healthy adult males using an incomplete block design. Addition of other nutrients to G led to a lowering of the glycaemic response. The lowest glycaemic responses were seen in case of meals containing the largest number of nutrients. P was more effective in reducing postprandial glycaemia than CL. As in case of glycaemic response, low insulinaemic responses were also associated with P-containing meals, and meals containing the largest number of nutrients. But unlike in case of glycaemic response, there was a tendency for elevation of the insulinaemic response in case of CL-containing meals. The degree of attenuation of glycaemic response observed with meals containing several nutrients was roughly predictable on the basis of the attenuation observed with meals in which only one nutrient had been added at a time to G. But the glycaemic response of natural foods is unlikely to be predictable on the basis of their nutrient composition because of the overriding influence of several other factors such as physical form, cooking, processing, storage and antinutrient content of the food.

Adolescent↗
PubMed1992

Congenital adrenal hyperplasia among peripubertal girls with hyperandrogenism.

Fifteen girls with severe hyperandrogenism were investigated by us during the last 6 years. Thirteen of these were cases of untreated congenital adrenal hyperplasia (CAH) and 2 were cases of tumoral (one sertoli leydig cell tumor of the ovary and one adrenal adenoma) hyperandrogenism. Here we present the clinical profile and laboratory data of those with congenital adrenal hyperplasia. All the girls had masculinization of genitalia (clitoromegaly alone 5, clitoromegaly with varying degree of posterior labial fusion 8). Eleven cases had hirsutism and 9 had short stature. Two patients underwent unilateral adrenelectomy with diagnosis of adrenal adenoma. Hormonal profile confirmed the diagnosis of CAH with 21 hydroxylase deficiency (elevated 17 OHP levels with exaggerated 17 OHP response to ACTH) in 12 cases and 3 beta hydroxy steroid dehydrogenase deficiency (elevated DHEAS and 17 pregnenelone levels and exaggerated DHEAS and 17 pregnenelone response to ACTH) in one case.

Adolescent↗
PubMed1991

Computed tomography in untreated congenital adrenal hyperplasia.

Six children with untreated congenital adrenal hyperplasia (CAH) were examined by computed tomography (CT). Three cases demonstrated diffuse enlargement of both adrenal glands with preservation of normal configuration and two showed tumorous transformation in one of the enlarged glands. One had equivocal enlargement of the adrenal gland. Even the youngest in this group (age 2 years) also showed bilateral hyperplasia.

Adolescent↗
PubMed1991

Modulation of postprandial glycaemia and insulinaemia by dietary fat.

The present study was designed to examine the effect of corn oil (Co) on postprandial glycaemia and insulinaemia when ingested with glucose (G), casein (Cs), cellulose (Cl) and pectin (P) in various combinations. The study was conducted on six healthy male volunteers, on each of whom six meal tolerance tests were performed. The meals were isocaloric and consisted of G; G and Co; G, Co and Cs; G, Co and P; G, Co, Cs and P; and G, Co, Cs and Cl. The meals were administered after an overnight fast. In addition to a fasting blood sample, blood was collected 0.5, 1.0, 1.5 and 2.0 h after ingestion for measurement of serum glucose and insulin levels. The glycaemic response to GCo was comparable to that to G, but the insulinaemic response was significantly lower. The glycaemic response to GCoCs was significantly lower than that to G but the insulinaemic response to both was comparable. The cellulose containing meal GCoCsCl showed a further reduction in the glycaemic response but not in the insulinaemic response. The pectin containing meals GCoP and GCoCsP gave the lowest glycaemic and insulinaemic responses, the responses to the latter being lower. Corn oil by itself has only a modest effect on the postprandial metabolic response to glucose. Addition of protein and fibre, specially pectin, leads to significant attenuation of glycaemic and insulinaemic responses.

Adult↗
PubMed1991

Glycaemic response to maize, bajra and barley.

The postprandial glycaemic response to maize (Zea mays), bajra (Pennisetum typhoideum) and barley (Hordeum vulgare) was studied in a pool of 18 healthy volunteers and 14 patients having non-insulin-dependent diabetes mellitus (NIDDM). In response to maize, none of the variables examined was significantly different as compared to white bread. The glycaemic response to bajra was significantly lower than that to white bread in healthy subjects, but the two responses were indistinguishable in NIDDM subjects. The insulinaemic responses to bajra and white break were not significantly different in either group of subjects. The glycaemic response to barley was significantly lower than that to white bread in both groups of subjects. But the insulinaemic response to barley was significantly lower than that to white bread only in healthy subjects. In NIDDM subjects, there was a tendency for the response to barley to be higher than that to white bread 0.5 h after ingestion. Barley, with a low glycaemic index (68.7 in healthy and 53.4 in NIDDM subjects) and a high insulinaemic index (105.2) in NIDDM subjects seems to mobilize insulin in NIDDM. This makes it a specially suitable cereal for diabetes mellitus.

Adult↗
PubMed1991

Clinical utility of ketoconazole in cases of adrenocortical carcinoma.

Ketoconazole, an imidazole derivative is known to decrease adrenal steroid biosynthesis by inhibiting cytochrome P450 dependent adrenal enzymes. Three patients of adrenal carcinoma treated with ketoconazole, 600-1200 mg daily showed significant fall in plasma and urinary cortisol levels, but no reduction in tumor size, one patient developed liver dysfunction which reverted back to normal on discontinuing the drug.

Adolescent↗
PubMed1990

Reproductive endocrine functions in men with primary hypothyroidism: effect of thyroxine replacement.

Reproductive endocrine functions were studied in men with primary hypothyroidism during the hypothyroid phase and after achieving euthyroid status with thyroxine substitution therapy. Hypergonadotropism [luteinising hormone (LH), 18.7 +/- 7.3 IU/l; follicle-stimulating hormone (FSH), 6.3 +/- 2.0 IU/l], low serum testosterone (6.1 +/- 2.8 nmol/l), low serum sex-hormone-binding globulin (SHBG; 13.2 +/- 2.0 nmol/l) and subnormal testosterone response to human chorionic gonadotropin hCG; (30% increase in serum testosterone following hCG) observed during the hypothyroid phase were restored to normal (LH, 7.2 +/- 2.0 IU/l; FSH, 2.7 +/- 0.9 IU/l; testosterone, 12.9 +/- 2.7 nmol/l; SHBG, 26.5 +/- 8.4 nmol/l, and 2-fold increase in serum testosterone following hCG) with thyroxine substitution therapy. Some improvement in sperm count and motility was also observed.

Adult↗
PubMed1990

Nutrient interaction in relation to glycaemic response in isocarbohydrate and isocaloric meals.

The present study was designed to examine the effect of casein (Cs) on postprandial glycaemia when ingested with glucose (G) alone or in combination with corn oil (Co), cellulose (Cl) or pectin (P). The study was conducted on a pool of ten healthy male volunteers in two sets of five volunteers each. The meals administered in the two sets were similar in composition but were isocarbohydrate (100 g G) in one set, and isocaloric (400 kcal) in another set. The meals in each set consisted of G, G Cs, G Cs Co, G Cs Cl and G Cs P. Each of the five volunteers in a given set underwent five meal tolerance tests (MTT), once with each meal, in a Latin Square design. During the MTT, the meal was administered after an overnight fast. In addition to a fasting venous blood sample, blood was collected 0.5, 1.0, 1.5 and 2.0 h after ingestion for measurement of serum glucose and insulin levels. In both sets, the highest glycaemic response was that to G. In the isocarbohydrate set, G Cs gave a significantly lower glycaemic and insulinaemic response than G. Further addition of Co made no essential difference but both the fibre containing meals gave significantly lower glycaemic responses. The insulinaemic response was attenuated only in case of G Cs P but not in case of G Cs Cl. In the isocaloric set, Cs as G Cs was observed to stimulate insulin secretion rather than attenuate postprandial glycaemia G Cs Co gave a reduction in glycaemic as well as insulinaemic response as compared to G. Both fibre containing meals led to further reduction in both responses, P being somewhat more effective than Cl. Addition of other nutrients to G, in general, reduces postprandial glycaemia.

Adolescent↗
PubMed1990

Increased brainstem angiotensin-I levels in chronic 2 KIC hypertensive rats.

A study was undertaken on the role of brainstem renin-angiotensin system in maintenance of hypertension in chronic renovascular hypertensive rats. Hypertension was induced by unilateral renal artery clamping, while the contralateral kidney was left intact (2 KIC). Blood pressure (BP), plasma renin activity (PRA) and brainstem angiotensin (ang-I) levels were measured after 24 days, in hypertensive and sham-operated animals. In separate subgroups of these animals, the effect of intracerebroventricular administration of captopril on the parameters listed was studied. The results showed high ang-I levels in 2 KIC rats as compared to controls (P less than 0.05). Captopril administration (500 micrograms/50 microliters icv) caused a fall in BP and increase in brainstem ang-I levels (P less than 0.01). In control animals, however, captopril produced a rise in BP without any significant change in brainstem ang-I levels. Peripheral plasma renin activity was normal, despite significant sodium retention in 2 KIC rats. The results are suggestive of activation of brainstem renin-angiotensin system (RAS) in chronic 2 KIC hypertension.

Angiotensin I↗
PubMed1989

Pregnancy and epilepsy.

In a prospective study, 30 pregnant epileptic patients were followed through their pregnancy to determine the effect of seizures on pregnancy and its outcome and the effect of pregnancy on seizures. An attempt was made to correlate the serum hormone and anticonvulsant drug levels with seizure frequency, complications of pregnancy, occurrence of status epilepticus and teratogenicity. In 14 patients seizure frequency increased, in 15 it remained unchanged and in 1 patient it decreased. There were 2 spontaneous abortions, 2 patients had status epilepticus and 1 offspring of a patient had a ventricular septal defect. This patient was receiving carbamazepine and diphenylhydantoin. Patients with increased seizures frequency had significantly higher oestrogen levels, lower level of progesterone and lower level of anticonvulsant drugs as compared with those with no change in seizures. Patients who had abortions and those who developed status epilepticus had high serum oestrogen levels.

Abnormalities, Drug-Induced↗
PubMed1989

Modulation of postprandial glycaemia and insulinaemia by cellulose in mixed nutrient combinations.

The present study was designed to examine the effect of cellulose (CL) on postprandial glycaemia and insulinaemia when ingested with glucose (G), casein (CS) and maize oil (CO) in various combinations. The study was conducted on five healthy male volunteers, on each of whom five meal tolerance tests were performed. The meals were isoenergetic and consisted of G; G and CL; G, CS and CL; G, CO and CL; G, CS, CO and CL. The meals were administered after an overnight fast. In addition to a fasting venous blood sample, blood was collected 0.5, 1.0, 1.5 and 2.0 h after ingestion for measurement of serum glucose and insulin levels. The glycaemic response to G + CS + CL and G + CS + CO + CL was significantly lower, while the insulinaemic response to G + CL was significantly higher than that to G. Addition of CL to G did not alter the glycaemic response, but accentuated the insulinaemic response. Further addition of CS in isoenergetic meals attenuated the glycaemic response, which may be because of a reduction in the amount of G in the meals. Like CS, CL also seemed to have an insulinotropic effect. The mechanism of the insulinotropic effect of CL cannot be deduced from the present study, but it is possible that like G, CL also stimulates gastric inhibitory peptide (GIP) secretion from the duodenum, which in turn stimulates insulin secretion.

Adult↗
PubMed1989

Profile of thyroid disorders in a referral centre in north India.

From 1983-88, 157 patients were investigated in our clinic for thyroid disorders: 117 (75%) were hypothyroid, 10 (6%)-hyperthyroid, and 30 had euthyroid goiters. Average age of presentation of congenital hypothyroids was 4.07 years. Children with goitrous hypothyroidism (n = 19) were divided into: (i) thyroiditis: RAIU low and patchy, TMA positive: 2 children; (ii) dyshormonogenesis: RAIU high, family history positive, perchlorate discharge test positive: 2 children; (iii) iodine deficiency: RAIU high, urinary iodine low: 2 children, and (iv) cause unknown: RAIU normal or high, other investigations normal: 13 children. Ninety eight hypothyroid children without goiter were divided into 6 groups: (i) athyreosis: RAIU low, no thyroid tissue identifiable (n = 39); (ii) hypoplasia: RAIU low, gland small, in normal position (n = 7); (iii) ectopia: RAIU low, gland in ectopic position (n = 24); (iv) thyroiditis: TMA positive (n = 2); (v) iodine deficiency: low urinary iodine (n = 1); and (vi) cause unknown: RAIU and scan normal, other investigations normal and not done (n = 8). Proportionate short stature was present in 44.4% children. Twenty two children presented only with growth failure; 72% of them had dysgenetic glands. Early onset marked the group with hyperthyroidism (n = 10). Euthyroid goiter was present in 30 (19%). Hypothyroidism is still being diagnosed very late. All children with growth failure, even if proportionate, must have thyroid status evaluated.

Body Weight↗
PubMed1988

Nutrient composition is a poor determinant of the glycaemic response.

1. The glycaemic response of healthy males to potato, bread, rice and green gram (Phaseolus aureus Roxb.) was compared with that to meals equivalent to these foods in terms of carbohydrate, protein, fat and fibre content, but made up of maize flour, casein, maize oil and ispaghula husk. 2. Natural foods led to a higher postprandial glycaemia than their respective equivalents, but the difference was significant only in the case of potato at 0.5 h (P less than 0.05). 3. The insulin response, studied only in the case of rice and green gram, followed a trend similar to the glycaemic response but the differences between natural foods and equivalents were even more marked. 4. A food is more than the sum of its major nutrients. Several poorly understood factors may contribute to the glycaemic response to a food. In addition to the quantity of nutrients, the response may be the result of the specific type of nutrients, non-nutrient chemicals and anti-nutrients composing the food, and their unique physical arrangement within the food.

Adult↗
PubMed1988

Late-onset adrenal hyperplasia in north Indian hirsute women.

The occurrence of late-onset congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency was studied in 60 consecutive hirsute women by means of adrenocorticotrophin (ACTH)-stimulated serum 17-hydroxyprogesterone (17-OHP) levels. Five (8.3%) women had an exaggerated response (ACTH-stimulated 17-OHP 3,160 +/- 560 ng/dl). All of them had regular periods and 3 were virilized. The other 2 were indistinguishable from those with idiopathic hirsutism or polycystic ovarian disease.

17-alpha-Hydroxyprogesterone↗