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K A Gumaa

Publications and source records attributed to K A Gumaa.

At least 37 records · Page 2Linked to original sources
PubMed1986

Site variability in the solubility of collagen of human fetal membranes.

The extractability of collagen was examined in different sites of amnion and chorion from term deliveries. Sequential extraction with NaCl, acetic acid and CaCl2 showed that soluble collagen accounted for 1.5% of the proteins extracted. Saline extracted more collagen from the amnion than from the chorion. Acetic acid and CaCl2 extracted decreasing and increasing amounts of collagen from the amnion and chorion respectively. The concentration of collagen decreased linearly in the chorion as the rupture site was approached. The results indicate differences in the nature of collagen between amnion and chorion as well as in various sites in the latter.

Acetates↗
PubMed1985

On the mechanism of the hypoglycaemic effect of a plant extract.

The efficacy of a hypoglycaemic plant extract, in common use by Kuwaiti diabetic individuals, was evaluated using both streptozotocin-induced diabetic and normal rats. A significant decrease in blood glucose concentration was demonstrated on glucose tolerance tests, as compared to untreated animals. The sum of the fasting, 1 and 2 h blood glucose values, decreased from 18.5 +/- 0.72 to 13.6 +/- 0.62 mmol/l (p less than 0.001) and from 58.6 +/- 2.83 to 44.5 +/- 3.12 mmol/l (p less than 0.005) in normal and diabetic animals treated for 1 week, respectively. Treatment with the extract was not found to significantly alter insulin levels or intestinal glucose absorption. The mode of action of the hypoglycaemic preparation remains to be elucidated.

Animals↗
PubMed1985

Blood coagulation and fibrinolysis in heat stroke.

Blood coagulation and fibrinolysis were assessed in 55 cases of heat stroke who presented with or without bleeding tendencies during the Makkah pilgrimage of 1983. 17 patients were identified to have evidence of disseminated intravascular coagulation (DIC). Bleeders with DIC had a higher incidence of shock and a higher mortality when compared to non-bleeders. Thrombocytopenia and liver cell damage were not limited to cases with DIC. Coagulation factors and serum enzyme studies suggested non-specific tissue damage as the trigger mechanism for DIC possibly proceeding through the extrinsic system of blood clotting. We conclude that the breakdown of haemostasis in heat stroke is multifactorial: thrombocytopenia, liver cell damage and DIC.

Blood Coagulation↗
PubMed1985

The structure and hormone content of the endocrine pancreas of the one-humped camel (Camelus dromedarius).

Little is known of the blood sugar regulation in the camel and the morphology and function of its endocrine pancreas. The present paper describes the light microscopic structure and hormone content of the endocrine pancreas of the one-humped camel. Staining of pancreatic sections with haematoxylin-eosin or aldehyde-fuchsin showed numerous islets evenly distributed in all parts of the pancreas. Immunocytochemical staining for insulin or glucagon indicated that islets were predominantly composed of centrally located B-cells, surrounded by a peripheral rim of A-cells. Corresponding stainings for somatostatin or pancreatic polypeptide (PP) demonstrated that D-cells comprised only a small part of the islet volume while PP-cells were common both within and outside the islets. There were no obvious differences between the frequency of the various islet cells in different pancreatic regions. The pancreatic hormone concentrations roughly corresponded to the frequency of the different islet cell types. Insulin appeared most abundant followed by glucagon, PP and somatostatin in decreasing order. The concentrations of each of the hormones were similar in different regions of the gland. It is concluded that the endocrine pancreas of the one-humped camel is dispersed into islets of the same size and cellular composition as has been described in many other mammalian species.

Animals↗
PubMed1985

Ultrastructure of the intrahepatic bile duct system of the one-humped camel (Camelus dromedarius).

The ultrastructure of the intrahepatic bile duct system of the camel was studied. Bile canaliculi are present as cavities containing numerous microvilli between adjacent hepatic cells. They are lined with cuboidal cells surrounded by a basal lamina. The lateral plasma membranes of adjacent cells form extensive evaginations below tight junctions at the lumenal surface. The basal surface is open. Collagen bundles are arranged mainly in parallel to the duct.

Animals↗
PubMed1984

Modulation of rat pancreatic islet cell replication and insulin release by glibenclamide.

Glibenclamide significantly stimulated the incorporation of [3H]thymidine into DNA of fetal rat pancreatic islets at a physiological (5.5 mM) but not at a high (22 mM) glucose concentration. There was no significant stimulation of insulin release under these conditions. In contrast, the drug-stimulated insulin release from adult islets cultured at 5.5 mM glucose but had no effect on their DNA synthesis. The observations suggest that insulin secretion and DNA synthesis may be dissociated in rat pancreatic islets.

Animals↗
PubMed1984

Metaraminol provocative test: a specific diagnostic test for familial Mediterranean fever.

The diagnosis of familial Mediterranean fever has been one of exclusion. In a placebo-controlled, double-blind, cross-over study a challenge with a 10 mg dose of metaraminol infusion was followed within 48 h by a typical disease-like attack in all of 21 patients with familial Mediterranean fever but in none of 21 control subjects. The induced attacks were milder and of shorter duration than the spontaneous ones. The metaraminol-induced symptoms were similar to the natural disease attacks and could be prevented with prophylactic colchicine therapy. No significant side-effects were observed.

Adolescent↗
PubMed1984

Effects of steroid hormones on DNA synthesis and insulin production of isolated foetal rat pancreatic islets in tissue culture.

This study describes the effects of prednisolone, oestradiol-17B and progesterone on DNA replication and insulin biosynthesis and release of cultured foetal rat islets. Prednisolone significantly inhibited the incorporation of [3H]-thymidine into DNA of islets cultured at a physiological (5.5 mmol/l) but not at a high (22 mmol/l) glucose concentration. It also increased insulin biosynthesis and release of islets cultured at 5.5 mmol/l glucose. Oestradiol-17B reduced the incorporation of [3H]-thymidine into islet DNA at both glucose concentrations, but had no effect on insulin biosynthesis and release. Progesterone had no effect on either the growth or the function of the cultured foetal islets. The observations show a clear dissociation between the action of prednisolone on islet growth versus islet function. They also support the view that neither progesterone nor oestradiol is directly involved in the high rate of B-cell replication previously observed in islets of pregnant rats.

Animals↗
PubMed1983

Effect of a hypoglycaemic sulphonylurea (HB419) and a non-metabolizable amino acid (BCH) on the insulin release and endogenous substrate metabolism of rat pancreatic islets.

The effects of the hypoglycaemia sulphonylurea glibenclamide (HB419) and the non-metabolizable leucine analogue beta-2-aminobicyclo(2.2.1)heptane-2-carboxylic acid (BCH) on insulin release and endogenous substrate metabolism were studied in isolated rat islets. Pre-labelling of the endogenous islet substrate was performed with [14C]glucose (20 mM) or [14C]glutamine (10 mM) during a 24 h tissue culture period before measurements of insulin release or 14CO2 production in short-term incubations. Both HB419 and BCH stimulated the insulin release of the cultured islets, although BCH only after culture of islets with glutamine. The rate of labelling of the islets with [14C]glucose reached an apparent plateau after 16 h in culture and the total islet accumulation of glucose carbon over the 24 h period averaged 12.9 +/- 3.0 nmol/25 islets. Less than 0.5% of the glucose residues was converted to glycogen whereas lipids represented about 2.5%. Fractionation of lipids showed 67% phospholipids, 18% triacylglycerols, 11% diacylglycerols and 6% non-esterified fatty acid. The islet accumulation of glutamine during 24 h corresponded to 11.5 +/- 1.5 nmol/25 islets. After pre-labelling of islets with [14C]glucose there was no effect on the 14CO2-evolution over a 30 min incubation period of either HB419 or BCH. There was also no effect of HB419 after pre-labelling with [14C]glutamine, whereas, in this latter situation, a significant stimulation was observed with BCH. It is concluded that the effects on the pancreatic B-cells by antidiabetic sulphonylureas are not mediated via nutrient receptors.

Amino Acids↗
PubMed1982

Biliary lipids in ox and sheep.

1. The lipids of gallbladder bile from sheep are more concentrated than in ox (P less than 0.001). 2. More than 90% of bile acids in both species are conjugated. 3. Taurocholate predominates in sheep while glycocholate predominates in bovine gallbladder bile. 4. The concentration of free bile acids i.e. lithocholate and (deoxycholate + chenodeoxycholate) is higher in bovine than in sheep gallbladder bile (P less than 0.001). 5. The ratio of conjugated to free bile acids is greater in sheep than in bovine gallbladder bile (P less than 0.010). 6. The ratio of total conjugated dihydroxy to trihydroxy bile acids is greater in bovine than in sheep gallbladder bile (P less than 0.001). 7. The ratio of the tauroconjugates of dihydroxy to trihydroxybile acids is higher in bovine than in sheep gallbladder bile (P less than 0.001). 8. It is concluded that the high fibre content of the diet of the two species studied stimulates the liver to form bile acids and hence the low lithogenicity of bile observed.

Animals↗
PubMed1979

Serum vitamin A levels of patients with onchocerciasis from two areas of the Sudan.

Two areas of the Sudan known to be endemic to onchocerciasis were surveyed for skin and ocular changes, and serum vitamin A levels in patients and normal controls. In Southern Sudan severe eye lesions and blindness are common complications. In Northern Sudan skin lesions predominate, and no case of blindness was recorded. Serum vitamin A levels were found to be adequate in all groups studied. However, patients from Southern Sudan with both eye and skin lesions due to onchocerciasis had the lowest mean serum vitamin A level. The significance of these findings is discussed in relation to the possible aetiological role of vitamin A deficiency in the pathogenesis of ocular complications of onchocerciasis.

Adolescent↗
PubMed1978

The effects of fasting in Ramadan. 1. Serum uric acid and lipid concentrations.

1. The changes in serum levels of uric acid and lipids during 1 month of starvation-refeeding were measured in sixteen male volunteers. 2. Uric acid levels increased linearly with the duration of the experiment. The increase was positively correlated with the increase in serum triglycerides but not with cholesterol or phospholipids. 3. Triglycerides increased at a faster rate than uric acid implying that the increase in uric acid was secondary to that of the lipid. 4. It was concluded that the purine and lipid synthetic pathways are linked through a common small-molecular-weight effector rather than through the sharing of a common enzyme.

Adult↗