PubMed Health⌕ Search

Biomedical subjects

K Ambo

Publications and source records attributed to K Ambo.

11 recordsLinked to original sources

Effects of feed restriction and cold exposure on glucose metabolism in response to feeding and insulin in sheep.

The effects of feed restriction, cold exposure, and the initiation of feeding on blood glucose metabolism, other blood metabolites, hormones, and tissue responsiveness and sensitivity to insulin were measured in sheep. The sheep consumed orchardgrass hay ad libitum (AL) or were restricted to 82% of the ME requirement for maintenance (RE) and were exposed to a thermoneutral (20 degrees C) or a cold environment (2 degrees C). An isotope dilution method and a glucose clamp approach were applied to determine blood glucose metabolism and insulin action, respectively. Plasma NEFA and insulin concentrations were influenced by feed restriction. Concentrations of plasma glucose, NEFA, insulin, and glucagon were influenced by cold exposure. Plasma NEFA concentration for RE decreased after the initiation of feeding and plasma insulin concentration increased transiently for all treatments. [U-13C]Glucose was continuously infused for 8 or 7 h after a priming injection starting 3 h before the initiation of either feeding or insulin infusion, respectively. When responses to feeding were studied, blood glucose turnover rate was less (P < .001) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The rate changed little after the initiation of feeding. For the glucose clamp approach, insulin was infused over four sequential 1-h periods at rates from .64 to 10 mU x kg BW(-1) x min(-1), with concomitant glucose infusion to maintain preinfusion plasma glucose concentrations. The rates of glucose infusion and blood glucose turnover increased (P < .001) dose-dependently with insulin infusion rate. The maximal glucose infusion rate was greater (P < .05) for RE than for AL and was greater (P < .001) during cold exposure than in the thermoneutral environment. The plasma insulin concentration at half-maximal glucose infusion rate was lower (P < .1) during cold exposure. Blood glucose turnover rate tended to be greater (P = .10) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The ratio of endogenous production to utilization of glucose was suppressed by insulin infusion. In sheep fed a roughage diet, blood glucose turnover rate seems to be influenced by both intake level and environmental temperature, but not by the act of feeding. Moreover, the action of insulin on glucose metabolism is enhanced during cold exposure, and the effect of feed restriction is somewhat enhanced.

Animals↗

Association of angiotensin-converting enzyme gene polymorphism and renal pathology in Japanese children with IgA nephropathy.

Polymorphism of the gene that codes for angiotensin I-converting enzyme (ACE) is associated with increased severity of immunoglobulin A (IgA) nephropathy in adult patients. We evaluated the relationship between the polymorphism of ACE genotypes and the pathological and clinical findings in Japanese children with IgA nephropathy. Patients with moderate/diffuse mesangial proliferation, glomerular sclerosis and tubulointerstitial damage showed a significant increase of the D/D type compared to those who had mild/focal mesangial proliferation, without glomerular sclerosis or tubulointerstitial damage (p < 0.05). Proteinuria at the first renal biopsy was significantly higher in the former group compared with the latter group except glomerular sclerosis (p < 0.01). IgA nephropathy patients with tubulointerstitial damage also showed an increased serum creatinine level compared to patients without the damage (p < 0.03). We conclude that ACE gene polymorphism may be correlated with the prognosis of IgA nephropathy in Japanese children.

Biopsy↗

Effect of mild cold exposure on whole-body and net hindquarters glucose metabolism in sheep.

Isotope dilution using [U-13C]glucose was combined with measurement of hindquarters arteriovenous difference and blood flow to examine the effect of mild cold exposure on whole-body and net hindquarters glucose metabolism in sheep. Determinations were carried out in a thermoneutral environment (20 +/- 1 degrees C) and on day 5 of mild cold exposure (4 +/- 1 degrees C). Whole-body blood glucose turnover rate was 1.56 and 1.91 mg kg-1 min-1 in the thermoneutral environment and during mild cold exposure, respectively. Net hindquarters glucose uptake was 0.79 and 1.19 mg kg-1 min-1, corresponding to 50 and 61% of whole-body turnover rate, respectively. These results suggest that in sheep the contribution of glucose uptake by the hindquarters tended to increase during mild cold exposure, even though whole-body blood glucose turnover rate did not increase significantly.

Animals↗

Incidence of hypocomplementemia in elementary and junior high school children with urinary abnormalities.

Abnormalities were detected in 2669 of 326,257 elementary and junior high school children (169,856 males and 156,401 females) who were screened at school for urinary abnormalities. Serum complement (C3) level was measured in all 2669 children having urinary abnormalities (811 males, 1856 females). Three had a serum C3 level that was more than three standard deviations below the mean value. Type I membranoproliferative glomerulonephritis (MPGN) was diagnosed on histological examination in one of these three children, while the other two did not undergo renal biopsy because they had serum C3 levels of 40 and 44 mg/dL, respectively, and because their urinary abnormalities were transient. It was considered that there is not much significance in testing the serum complement in the urine screening done at school and the cost/benefit ratio is low. The results appeared to reflect the frequency of persistent hypocomplementemic MPGN in Japan in recent years.

Adolescent↗

CD3-negative lymphoproliferative disease of granular lymphocytes in a girl with an unusual pattern of anti-Epstein-Barr virus antibodies.

UNLABELLED: We describe an 11-year-old girl who initially had mild hepatosplenomegaly and then presented with abnormal expansion of CD3-negative granular lymphocytes in peripheral blood and Epstein-Barr virus (EBV) genome in the DNA obtained from the peripheral blood mononuclear cells (PBMNC). After approximately 3 years, she developed oedema, ascites, marked hepatosplenomegaly, and pancytopenia, and showed both a profile of anti-EBV antibodies of reactivated infection and a high titre of anti-cytomegalovirus antibody. Although she was treated with antibiotics, ganciclovir, and prednisolone, she died of hepatic failure. CONCLUSION: Careful clinical observation, periodic examination of anti-EBV antibodies, and the analysis of EBV genome from PBMNC are needed in young patients with CD3-negative lymphoproliferative disease of granular lymphocytes.

CD3 Complex↗

Infant botulism with Down syndrome.

A 4-month-old boy with Down syndrome and infant botulism is reported. He was admitted to our hospital with stridor and developed respiratory failure and generalized paralysis. Laboratory examination revealed botulinal toxin type A in his blood and feces. Clostridium botulinum organisms were found in the feces and in the honey which he had been fed. Anti-botulinal toxin was administered on the 10th day of illness. Artificial ventilation was given for 87 days and he survived. This is the 11th known case of infant botulism in Japan. It is possible that other cases remain undiagnosed.

Botulinum Antitoxin↗

Blood glucose kinetics in whole body and mammary gland of lactating goats exposed to heat.

Whole-body and mammary kinetics of blood glucose were measured in lactating goats exposed to thermoneutral, moderate hot, and severe hot environments for 4 d. Milk yields were reduced by 3 and 13% during moderate and severe heat exposure, but heat production was unchanged during the experiment. Concentrations of plasma glucose and free fatty acids did not change during heat exposure. Concentration of thyroxine tended to decrease and concentration of prolactin increased with increasing temperature. Whole-body turnover of blood glucose decreased significantly during both moderate and severe heat exposure. Blood glucose oxidation rate and contribution of blood glucose to total carbon dioxide production were not influenced by heat exposure. Mammary glucose uptake tended to decrease during heat exposure, and this reduction may account for the decreased whole-body turnover of blood glucose. The lactose concentration in milk was decreased on the 4th d of severe heat exposure. A relatively low production of milk lactose was apparently derived from blood glucose. These results suggest that the whole-body turnover of blood glucose decreases in step with a decrease in mammary glucose uptake during heat exposure in lactating goats.

Animals↗

Turnover and oxidation rates of blood glucose and heat production in sheep exposed to heat.

Five shorn sheep were used to study effects of heat exposure (30 degrees C, relative humidity 70%) on metabolism of blood glucose and heat production. The isotope dilution method was applied for determination of metabolism of blood glucose in a thermoneutral environment (20 degrees C, relative humidity 70%) and on the 4th and 10th days of heat exposure. Concentrations of free fatty acids and thyroxine of plasma decreased during heat exposure with no reduction in feed intake. At 20 degrees C, glucose turnover rate, percentage of glucose oxidized, and contribution of exhaled carbon dioxide derived from glucose to the total carbon dioxide production were 6.2 mg/kg.75 per min, 34%, and 11%. Glucose turnover rate decreased significantly during heat exposure, but the proportion of glucose oxidized was unchanged. Heat production decreased almost parallel to the glucose turnover rate during heat exposure, resulting in an unchanged contribution of carbon dioxide derived from glucose to the total production of carbon dioxide. Blood glucose metabolism and heat production of sheep decrease, but the contribution of blood glucose to heat production remains unchanged during exposure to 30 degrees C.

Animals↗

Clinical, hematological and pathological responses in severely heat-stressed steers with special reference to the threshold value for survival.

To find out a critical point of physiological responses of steers which would finally lead to death due to heat stress, four Holstein steers weighing about 300 kg were housed in an artificial climatic room and exposed to each of the following room temperature and relative humidity: 35 degrees C and 70 per cent, 36 degrees C and 80 per cent, 38 degrees C and 70 per cent, and 42 degrees C and 60 per cent. Sequential clinical and hematological examinations were carried out during thermal loads on the steers, and pathological examinations after their death or slaughter. All the steers manifested panting, rise of rectal temperature, reduction or disappearance of peristalsis, hypersalivation, dysfunction of the skin reflex, and remarkable decrease in white blood cell count and pressure of CO2 (Pco2) value of jugular blood. At the end of heat stress, an animal would be survived if it meet the following conditions: (1) rectal temperature was below 42.7 degrees C, (2) the respiration rate did not decrease to one half (about 100/minute) of the maximum rate during the exposure period, (3) peristalsis and skin reflex disappeared almost completely, (4) the white blood cell count did not decrease to less than 50 per cent of the normal level, and (5) the Pco2 value of venous blood was maintained at a level of more than 15 mmHg. Cloudy discoloration with a boiled-meat appearance was noticed in the skeletal muscle of the hind part of the body in two dead cases. No significant changes were detected in any other steer slaughtered several days after release from the thermal stress.

Animals↗