Search PubMed⌕ Search

Biomedical subjects

M J Pettei

Publications and source records attributed to M J Pettei.

10 recordsLinked to original sources
PubMed1991

Essential fatty acid deficiency associated with the use of a medium-chain-triglyceride infant formula in pediatric hepatobiliary disease.

Serum phospholipid fatty acid patterns were determined by gas chromatography in four infants with hepatobiliary disease receiving a formula with a high content of medium-chain-triglyceride (MCT) oil. All four infants demonstrated signs of essential fatty acid deficiency, characterized by decreased arachidonic acid and increased palmitoleic and oleic acids. All had substantial concentrations of the pathologic triene 5,8,11-eicosatrienoic acid. Three of four had decreased linoleic acid concentrations and abnormal ratios of triene to tetraene (5,8,11-eicosatrienoic acid: arachidonic acid), greater than 0.38. One patient may have experienced growth failure due to abnormal essential fatty acid status. Infants with the potential for fat malabsorption should only receive MCT-oil feedings with well above the generally recommended requirements for linoleic acid (3% of total caloric intake).

Cholestasis↗
PubMed1991

Liver uptake of trypsin-inhibitor complexes; differences between suckling and adult rats.

Previous studies have demonstrated increased intestinal trypsin uptake in newborn rats compared to adults. The mechanisms that protect tissues against proteolytic damage by trypsin include trypsin-inhibitor binding and subsequent liver uptake. In order to examine these mechanisms, bovine trypsin (1.25 mg/100 g body weight) plus trace 125I-trypsin were injected into the portal vein of 2-week-old and adult rats. Liver, kidney and plasma 125I activity were assessed at 1, 5 or 15 min following infusion and the different trypsin inhibitor fractions were separated and examined for 125I activity. Newborn rats had significantly increased plasma levels of 125I-trypsin and significantly decreased liver 125I levels 1 min after infusion compared to adults. In addition, the slow decline in liver 125I activity seen in the adult rats did not occur in the newborns. The pattern of trypsin-inhibitor binding was not significantly different at 1, 5 and 15 min and there were no differences at these time intervals between newborns and adults. We suggest that the newborn liver is less effective in clearing infused trypsin leading to increased plasma levels, and this increased plasma trypsin concentration subsequently leads to increased liver levels of 125I-trypsin. The increased trypsin levels in the liver may predispose newborns to protease-induced liver damage.

Acute-Phase Proteins↗
PubMed1990

Nonocclusive mesenteric ischemia associated with propranolol overdose: implications regarding splanchnic circulation.

We describe a case of massive propranolol overdose in a healthy 19-year-old woman associated with isolated mesenteric ischemia following shock. We postulate that endogenous catecholamine release from shock combined with massive beta-adrenergic blockade led to severe splanchnic vasoconstriction from unopposed alpha-adrenergic activity. This case supports current thinking regarding the effect of vasoactive mediators on the gastrointestinal tract in humans and might be relevant to the mechanism of action of propranolol in the prophylaxis of variceal bleeding.

Adrenergic beta-Antagonists↗
PubMed1989

Trypsin uptake and trypsin-inhibitor complexes. Differences between suckling and adult rats.

Previous studies have suggested that both newborn animals and humans absorb intact proteases from the intestine in greater amounts than do adults. Absorbed proteases are rapidly complexed in plasma by several inhibitors which inactivate free proteases. In order to confirm increased intestinal uptake in newborns, we evaluated the plasma trypsin activity in both 2-week-old and adult rats following a trypsin feed. In addition, we studied the interaction between absorbed trypsin and rat trypsin inhibitors (alpha-macroglobulin, alpha 1-inhibitor 3, and alpha 1-protease inhibitor) by determining the concentration of alpha-macroglobulin complexes both in vivo and in vitro following trypsin feeding and by evaluating the amount of trypsin activity complexed with the different inhibitors. In vivo experiments demonstrated that trypsin uptake was significantly increased in newborns compared to adult rats and that 50-70% of plasma trypsin activity was associated with alpha 1-inhibitor 3. Increased uptake was not accompanied by increased alpha-macroglobulin complexes. In vitro trypsin incubation did not lead to increased alpha-macroglobulin complexes until the other inhibitors were removed. These findings suggest that newborns have increased trypsin uptake, and the trypsin initially binds to alpha 1-inhibitor 3 before being transferred to alpha-macroglobulin for clearance. Further studies are needed in order to understand the interaction between intestinal uptake and plasma inhibition of absorbed proteases.

Aging↗
PubMed1977

Identification of retinal isomers isolated from bacteriorhodopsin.

The purple membrane of Halobacterium halobium contains the protein bacteriorhodopsin which resembles the visual pigment, rhodopsin, in many aspects. The isomeric configurations of its chromophore, retinal, were studied by a combination of methylene chloride extraction and analysis by high-pressure liquid chromatography. The light-adapted form bR570LA yields solely all-trans-retinal, while the dark-adapted form of bacteriorhodopsin, bR560DA, yields a mixture of 13-cis and all-trans with a ratio of similar to 1;1. The photointermediate M412 in a membrane modified by ether at high NaCl concentration also yields an approximately 1:1 mixture of 13-cis-and all-trans-retinals, while a similar M405 species produced by illumination in 2 M guanidine hydrochloride at high pH yields mainly 13-cis-retinal. These results indicate that the photochemical cycle of bR570LA may involve an isomerization of the retinal chromophore from the all-trans to the 13-cis form.

Bacteriorhodopsins↗
PubMedDate not supplied

Dysfibrinogenemia in obstructive liver disease.

Acquired dysfibrinogenemia was documented in a 4-year-old child with obstructive jaundice of 1-month duration, secondary to a choledochal cyst involving the distal common bile duct. It was characterized by decreased thrombin coagulable protein with elevated immunoassayable fibrinogen resulting in abnormal thrombin and reptilase times. The liver morphology was compatible with extrahepatic obstruction, without evidence of cirrhosis or hepatocyte abnormality. All the coagulation abnormalities promptly resolved after surgical correction of the obstruction. Dysfibrinogenemia has been associated with serious liver disease in adults, including tumors, chronic active hepatitis, and cirrhosis, but never with isolated obstructive jaundice. This report documents a case of acquired dysfibrinogenemia due to extra-hepatic biliary obstruction and also emphasizes the importance of the consideration of this disorder in coagulation abnormalities associated with hepatobiliary disease.

Blood Coagulation Disorders↗