ABSTRACT
Tailgut cyst (TGC), also called retrorectal hamartoma, is a rare congenital lesion arising from persistent remnants of the postanal gut. Malignant transformation of TGC is exceedingly uncommon. We report herein the clinicopathologic features and the follow-up of a new case of a TGC with adenocarcinomatous transformation occurring in a 61 year-old woman.
Subject(s)
Adenocarcinoma/etiology , Cysts/complications , Rectal Neoplasms/etiology , Cysts/congenital , Fatal Outcome , Female , Humans , Middle AgedABSTRACT
Propionyl-L-carnitine (PLC), a natural short-chain derivative of L-carnitine, has been tested in this study as a potential protective agent against adriamycin (ADR)-induced cardiotoxicity in isolated rat heart myocytes and mitochondria. In cardiac myocytes, ADR (0.5 mM) caused a significant (70%) inhibition of palmitate oxidation, whereas, PLC (5 mM) induced a significant (49%) stimulation. Addition of PLC to ADR-incubated myocytes induced 79% reversal of ADR-induced inhibition of palmitate oxidation. In isolated rat heart mitochondria, ADR produced concentration-dependent inhibition of both palmitoyl-CoA and palmitoyl-carnitine oxidation, while PLC caused a more than 2.5-fold increase in both substrates. Preincubation of mitochondria with 5 mM PLC caused complete reversal of ADR-induced inhibition in the oxidation of both substrates. Also ADR induced concentration-dependent inhibition of CPT I which is parallel to the inhibition of its substrate palmitoyl-CoA. In rat heart slices, ADR induced a significant (65%) decrease in adenosine triphosphate (ATP) and this effect is reduced to 17% only by PLC. Results of this study revealed that ADR induced its cardiotoxicity by inhibition of CPT I and beta-oxidation of long-chain fatty acids with the consequent depletion of ATP in cardiac tissues, and that PLC can be used as a protective agent against ADR-induced cardiotoxicity.
Subject(s)
Antibiotics, Antineoplastic/antagonists & inhibitors , Antibiotics, Antineoplastic/toxicity , Cardiotonic Agents/pharmacology , Carnitine/analogs & derivatives , Doxorubicin/antagonists & inhibitors , Doxorubicin/toxicity , Fatty Acids/metabolism , Mitochondria, Heart/metabolism , Adenosine Triphosphate/metabolism , Animals , Cardiotonic Agents/metabolism , Carnitine/metabolism , Carnitine/pharmacology , Carnitine O-Palmitoyltransferase/metabolism , In Vitro Techniques , Male , Mitochondria, Heart/drug effects , Myocardium/cytology , Myocardium/metabolism , Oxidation-Reduction , Palmitates/metabolism , Palmitoyl Coenzyme A/metabolism , Proteins/metabolism , Rats , Rats, Sprague-DawleyABSTRACT
The concentrations of serum total lipids, cholesterol and triglycerides of guinea pigs were determined under normal conditions and after 5 days fasting. Serum glucose and liver glycogen levels were also estimated under both conditions. The amounts of serum total lipids and cholesterol were significantly increased as a result of starvation, whereas, fasting had no significant effect on serum triglycerides. Liver glycogen was rapidly decreased in response to starvation in a highly significant manner. However, starvation did not affect serum glucose of guinea pigs.
