Biomedical subjects

T R LaPine

Publications and source records attributed to T R LaPine.

4 recordsLinked to original sources

PubMed1988

Portal venous and aortic glucose and lactate changes in a chronically catheterized rat.

A method for portal venous, aortic, and gastric cannulation in the rat is described. Changes in mean portal venous and aortic blood glucose and lactate concentrations after an intragastric infusion of d-glucose to chronically catheterized rats (after regaining preoperative weight) were compared to those of acutely catheterized rats (1 h after catheter placement). Both portal venous and aortic catheters were patent for blood sampling in 67% of rats 8 days after catheter placement and 42% after 14 days. After intragastric infusion of 10 ml of 0.29 M dextrose, mean aortic blood glucose and lactate concentrations in chronically catheterized rats increased 80 and 73%, respectively, 15 min after infusion and decreased to preinfusion concentrations by 60 min. In acutely catheterized rats, mean aortic glucose and lactate concentrations increased linearly for 60 min. The concentration differences between portal venous and aortic blood glucose and lactate concentrations in chronically catheterized rats were not significantly different than baseline differences. The portal venous glucose concentrations were significantly greater than aortic concentrations in acutely catheterized rats 15, 30, and 45 min after the glucose infusion when compared to baseline differences. These data suggest that the rate of glucose uptake and metabolism to lactate is significantly altered in acutely catheterized rats when compared to chronically catheterized animals.

Alanine↗

PubMed1988

The effect of fasting on rat portal venous and aortic blood glucose, lactate, alanine, and glutamine.

Using a chronically catheterized rat model, the effect of fasting on portal venous, aortic, and venous blood concentration minus aortic blood concentration ([PV-A]) blood glucose, lactate, alanine, and glutamine concentrations was determined. It has been postulated that the intestine is a source of lactate and alanine, precursors for glycogen synthesis, in the fed state. After 48 h of fasting portal venous glucose, lactate, and alanine blood concentrations decreased by 31, 28, and 41%, respectively. Portal venous glutamine concentration was not affected by fasting. A glucose [PV-A] was not found in either fed or fasted states. Whereas the lactate [PV-A] was not present in fed rats, it was negative in fasted rats. Alanine [PV-A] was positive in fed and fasted rats. The glutamine [PV-A] was negative in fed and fasted rats. These data indicate that portal venous concentrations of the gluconeogenic precursors, lactate and alanine, decrease in fasted rats. In fasted rats intestinal utilization of lactate increases as reflected by a negative [PV-A]. Fasting did not affect alanine production by the intestine or glutamine utilization. Despite these changes with fasting, we conclude that the intestine does not appear to be able to maintain portal venous blood concentrations of gluconeogenic precursors.

Alanine↗

PubMed1985

Neonatal back-transport. Cost-effectiveness.

This study examines the cost-effectiveness of returning previously ill neonates to community hospitals after treatment in a tertiary center, a concept known as "back-transport." The authors compared the charges for medical care during convalescence of a group of back-transported infants (BT infants; n = 20) with a similar group of infants who remained in a tertiary center for convalescence (NT infants; n = 20). The total charges for convalescent care (inpatient plus transport charges) for 20 representative BT infants was $61,840, compared with $68,240 for 20 matched NT infants, an average savings of $320 per BT infant. The average daily bed charge and charges for laboratory tests and medications were significantly less for BT infants compared with NT infants, and these reductions offset the transport charges for BT infants. The authors conclude that back transport decreases the charges for medical care for most infants. Therefore, the decision to back-transport an individual infant usually can be based on factors other than cost.

Convalescence↗

PubMed1985

Treatment to prevent postnatal loss of brain water reduces the risk of intracranial hemorrhage in the beagle puppy.

We compared the risk of intracranial hemorrhage after a hypovolemic, hypotensive insult followed by rapid volume replacement in three groups of beagle puppies: one group less than 12 h old, a second, 72 h of age, and a third, 72 h of age, which had been treated from birth with ovine prolactin in the dose per kilogram which prevents postnatal brain water loss in rabbits. Intracerebral hemorrhage occurred in 14% of day 1 animals, 68% of untreated animals on day 3, and 15% of the group treated with prolactin. These data suggest that postnatal loss of brain water predisposes to intracerebral hemorrhage and that treatment to prevent this water loss can reduce the risk of intracerebral hemorrhage at 72 h of age.

Animals↗