Carnitine supplementation accelerates normalization of food intake depressed during TPN

When total parenteral nutrition (TPN; containing glucose, fat, and amino acids; caloric ratio 50:30:20) providing 100% of the rat's daily caloric intake is given for 3-4 days, food intake rapidly decreases by approximately 85%. After stopping TPN, there is a lag period of 3-4 days before food intake returns to previous level, which appears to be related to fatty acid oxidation and fat deposition. Carnitine plays a key role in the oxidation of fatty acids, and was demonstrated to reduce fat deposition in rats receiving TPN, by increasing beta oxidation. We therefore investigated whether rats receiving TPN supplemented with carnitine may prevent either the decrease or speed up the resumption or normalization of food intake, after TPN is stopped. Fourteen adult Fischer-344 rats had a central venous catheter inserted. After 10 recovery days, controls (n = 7) were infused with TPN providing 100% of rat's daily caloric intake for 3 consecutive days, followed by 4 more days of normal saline. The carnitine group (n = 7) received the same solution, but which provided 100 mg/kg/day carnitine. Daily food intake was measured and data were analyzed using ANOVA and Student's t-test. Both parenteral solutions depressed food intake maximally by almost 90% by day 3. Carnitine accelerated the normalization of food intake by decreasing the lag period by 1 day. We conclude that the addition of carnitine enhanced the normalization of post-TPN food intake and argue that this may be on the basis of enhanced fatty acid oxidation, a substrate known to play a significant role in the anorexia induced by TPN.     

Breathing of awake goats during prolonged dysfunction of caudal M ventrolateral medullary neurons

Recent scientific studies have demonstrated the efficacy of various forms of immunotherapy for the treatment of allergic diseases. Traditional subcutaneous immunotherapy, sublingual, oral, and intranasal immunotherapy have been shown to significantly reduce symptoms and favorably modulate the immune response. Outcome studies that use patient response data from standardized surveys represent the next challenge to all practicing allergists.     

Renoprotective differences between perindopril and enalapril in the diabetic hypertensive rat do not reflect glomerular angiotensin-converting enzyme activity

1. The various angiotensin-converting enzyme inhibitors have structural differences which affect their affinities for the catalytic sites on converting enzyme. We postulated that such differences might result in differences in renoprotective efficacy. We investigated this in the diabetic spontaneous hypertensive rat. We also investigated whether these differences might reflect variations in glomerular or plasma angiotensin-converting enzyme activity. 2. One week after induction of diabetes, rats were started on antihypertensive therapy: enalapril, 10 mg.day-1.kg-1, or perindopril, 4 mg.day-1.kg-1, in the drinking water. After 3 months, the rats were killed, blood samples were taken and tissues were harvested. Angiotensin-converting enzyme activity in isolated glomeruli and plasma was measured by fluorimetric assay. Glomerular protein content was also determined. 3. Urinary protein excretion was significantly lower in perindopril-treated rats than in either controls (P < 0.0005) or enalapril-treated rats (P < 0.05). Glomerular protein content was also lower in perindopril-treated rats (P < 0.05 versus enalapril; P < 0.005 versus control). There was no difference in glomerular angiotensin-converting enzyme activity between the two inhibitors although both were lower than control values (enalapril P < 0.025; perindopril P < 0.025). Plasma angiotensin-converting enzyme activity was significantly lower in the perindopril group than in either control (P < 0.005) or the enalapril group (P < 0.01). 4. We conclude that in the spontaneous hypertensive rat with streptozotocin-induced diabetes, perindopril is more effective than enalapril in reducing proteinuria and glomerular protein accumulation. This difference does not result from differences in glomerular-converting enzyme activity.     

Influence of soft tissue on density and relative contrast between gutta-percha and dentin images. An in vitro study

Factor XII initiates the intrinsic coagulation cascade and may affect the fibrinolytic system. Routine coagulation tests used during cardiopulmonary bypass (CPB) are abnormal in factor-XII-deficient patients and are useless for monitoring anticoagulation in these patients. A factor-XII-deficient patient requiring CPB is described. The baseline celite activated clotting time (ACT) was greater than 1400 seconds and the thrombin time was 12.4 seconds (control, 11.9 seconds). Two units of plasma were given resulting in an ACT of 173 seconds. Following 300 units/kg of heparin and during CPB, the ACT ranged from 670-596 seconds with the thrombin time greater than 200 seconds. Plasma provides exogenous factor XII allowing an endpoint on the ACT test and may protect against possible postoperative hypofibrinolytic complications. A commercially available modified thrombin time may also be useful and provide an endpoint during high-dose heparinization.     

Amphetamine-induced behavior, dopamine release, and c-fos mRNA expression: modulation by environmental novelty

We have shown recently that the psychomotor activating effects of amphetamine in the rat are much greater when this drug is administered in association with environmental novelty than when it is given in a home environment. The main purpose of the present study was to explore the neural basis of this phenomenon. We found, using in situ hybridization of c-fos mRNA, that the pattern of neuronal activation in the cortex, in the caudate, in the shell and core of the nucleus accumbens, and in other subcortical structures was markedly different when amphetamine (2.0 mg/kg, i.p.) was given in association with exposure to environmental novelty relative to when it was given at home. In most brain regions the magnitude of c-fos expression was over two times greater in rats given amphetamine plus novelty than in rats given amphetamine alone. In contrast, an in vivo microdialysis study indicated that environmental novelty did not affect amphetamine-induced dopamine release in either caudate or nucleus accumbens. Furthermore, a unilateral 6-hydroxydopamine lesion of the mesostriatal dopamine system reduced amphetamine- but not novelty-induced c-fos expression. Finally, we found no differences in the amount of corticosterone secreted after exposure to novelty, amphetamine, or both, suggesting that corticosterone does not play a critical role in the ability of novelty to modulate amphetamine-induced psychomotor activation. In conclusion, it seems that environmental novelty alters the neurobiological effects of amphetamine independently of the primary neuropharmacological actions of this drug in the striatum.     

Detection of infectious disease agents in tissue by immunocytochemistry

1. Immunocytochemical procedures have played an increasingly larger role in the identification of infectious disease agents in tissue sections owing to the increased availability and specificity of antibody reagents, the great sensitivity of the methods, and the relative facility with which the studies are performed. 2. Immunocytochemical methods can be applied to routine formalin-fixed tissue for the detection of infectious agents such as viruses, bacteria, fungi, and protozoa among other microorganisms for diagnostic and research purposes.