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Dive into the research topics where Marvin E. Ament is active.

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Featured researches published by Marvin E. Ament.


Clinical Nutrition | 1993

Low plasma free choline is prevalent in patients receiving long term parenteral nutrition and is associated with hepatic aminotransferase abnormalities

A.L. Buchman; A. Moukarzel; Donald J. Jenden; Margareth Roch; Kathleen M. Rice; Marvin E. Ament

Hepatic transaminase abnormalities have been previously reported in patients receiving long term total parenteral nutrition (PN). We sought to determine if such abnormalities are caused by choline deficiency-induced hepatocyte damage. In 41 subjects (19 male, 22 female) aged 45.1 +/- 24.3 years (range 0.1-79 years) who have received PN for 5.5 +/- 4.7 years (range 0.1-14.5 years). We determined plasma free and phospholipid bound choline levels, serum albumin, ALT and AST. We also determined the daily volume of intravenous lipid emulsion received by the patients as well as the concentration of free choline and phospholipid bound choline in the lipid emulsion. Plasma free choline was low in 33 41 subjects (mean 7.15 +/- 2.5 nmol/ml, range 3.3-15.6, normal 11.4 +/- 3.7). Phospholipid bound choline was normal in 34 41 subjects (mean 2157 +/- 620 nmol/ml, range 1026-3887, normal 2364 +/- 774). Elevations in ALT and AST were significantly correlated with plasma free choline (r = -0.34, p = 0.03, r = -0.37, p = 0.02 respectively) but not with phospholipid bound choline. No relationship was found between age, PN duration or daily volume of intravenous lipid and plasma free or phospholipid bound choline. The lipid emulsion contained 24 +/- 6 nmol/ml of free choline and 11 630 +/- 552 nmol/ml of phospholipid bound choline. We conclude that low plasma free choline is prevalent in patients receiving long term PN and this abnormality is associated with elevated serum aminotransferases. Furthermore, intravenous lipid emulsion is an inadequate source of choline for this patient group.


Pediatric Clinics of North America | 1988

Fiberoptic upper intestinal endoscopy in infants and children

Marvin E. Ament; William E. Berquist; Jorge Vargas; Vojislav Perisic

Fiberoptic upper intestinal endoscopy has been shown in the last decade to be the most sensitive technique to diagnose upper gastrointestinal disease. Diagnostic endoscopy has been shown to be safe, with a low complication rate of less than 2 per cent, and most of those reported have been minor. Furthermore, therapeutic endoscopy has been used to treat bleeding varices by sclerotherapy, avoiding the need for shunting procedures, which often fall in young children. Dilation of strictures with wire-guided dilators, endoscopic incision of antral mucosal diaphragms, and percutaneous placement of gastrostomy tubes are other ways endoscopy is being used as a means of treatment. Electrocoagulation and photocoagulation of bleeding upper gastrointestinal lesions have not been used.


Clinical Nutrition | 1994

Catheter thrombosis and superior/inferior vena cava syndrome are rare complications of long term parenteral nutrition

A.L. Buchman; S. Misra; A. Moukarzel; Marvin E. Ament

The objective of this study was to determine the incidence of catheter thrombosis and superior/inferior vena cava (SVC IVC ) syndrome in a large population of patients receiving home total parenteral nutrition (TPN), using retrospective data collection and analysis. 527 patients including 138 children who were discharged on home TPN and followed in the UCLA home TPN program for a minimum of one week between April, 1973 and October, 1991. There was a total of 1154 years of patients follow-up, including 241 years in children. Fifty-seven patients (11%) developed 81 episodes of catheter thrombosis excluding SVC IVC syndrome with an incidence of 0.07 episodes per catheter year. The median catheter duration prior to thrombosis was 7 months. Twenty-one thromboses occured in children with an incidence of 0.09 per catheter year. Eleven percent of thrombotic episodes were associated with catheter sepsis. Thirty-nine percent of patients had a PTT less than control values. Twenty-two patients including 6 children developed SVC IVC syndrome with an incidence of 0.02 per catheter year. SVC IVC syndrome was not associated with catheter sepsis in any patient. Sixty-eight percent of patients had catheter thrombosis at some point prior to developing SVC IVC syndrome. It is concluded that catheter-related thrombotic events are rare complications of home TPN and are uncommonly associated with infection. However, we recommend warfarin anticoagulation following an initial thrombotic event, in the absence of catheter malposition, for all such patients as long as they maintain a central venous catheter.


Transplantation | 2001

Orthotopic liver transplantation for autoimmune hepatitis and cryptogenic chronic hepatitis in children

Rj Bahar; Gs Yanni; Martin G. Martin; Sue V. McDiarmid; Jorge Vargas; Gb Gershman; Melvin B. Heyman; Philip J. Rosenthal; Tipton; P Nanjundiah; A Starr; Marvin E. Ament

BACKGROUNDnAutoimmune hepatitis (AIH) and cryptogenic chronic hepatitis (CCH) are important causes of liver failure in children, frequently necessitating orthotopic liver transplantation (OLT). The aim of this study is to review disease progression and potential differences between subgroups of children with AIH and CCH.nnnMETHODSnThe medical records of 65 children diagnosed with AIH or CCH between 1980 and 1998 were evaluated.nnnRESULTSnThe median age at presentation was 9 years, 8 months (range 4 months-19 years), and the median follow-up period was 8 years (range 3 months-18 years, 10 months). Forty-one patients (63%) were female. Twenty-eight patients were Hispanic, 28 were Caucasian, 8 were African-American, and 1 was Asian. Forty-three patients (66%) were diagnosed with type 1 AIH, 8 (12%) with type 2 AIH, and 14 (22%) with CCH. Forty patients (62%) underwent OLT (51% of those with type 1 AIH, 75% of those with type 2 AIH, and 86% of those with CCH). Thirteen (33%) of the transplanted patients experienced disease recurrence. African-American patients experienced a significantly higher rate of disease recurrence post-OLT than did Hispanic patients. Seven patients (11%) died, two without OLT, and five posttransplantation.nnnCONCLUSIONSnAIH and CCH frequently necessitate OLT in children. CCH is a more aggressive disease than Type 1 AIH among children with these disorders. Ethnicity influences the rate of disease recurrence after liver transplantation.


Digestive Diseases and Sciences | 1994

Reversal of megaduodenum and duodenal dysmotility associated with improvement in nutritional status in primary anorexia nervosa

Alan L. Buchman; Marvin E. Ament; Marvin Weiner; Anatoly Kodner; Emeran A. Mayer

SummaryAnorexia nervosa is considered one type of eating disorder that may result in severe malnutrition. Patients with this disorder commonly complain of postprandial nausea, abdominal pain, and distension. We describe the radiologic and motility abnormalities associated with anorexia nervosa in a 21-year-old female. Barium gastrointestinal series demonstrated marked dilation of the duodenum, with prolongation of intestinal transit. A 4-hr fasting gastroduodenal motility study showed no propagating migrating motor complexes (MMC). Prolonged, but nonpropagating, bursts of high-amplitude phasic and tonic contractions were seen in the duodenum. In contrast, antral contractions were of low amplitude and esophageal motor function was normal. Metoclopramide and edrophonium caused an increase in gastroduodenal motor activity, but increased contractions were not associated with symptoms. Following a renutrition program that raised the patients weight from 64 to 80% of her ideal body weight, the radiographic abnormalities and gastrointestinal dysmotility resolved completely. These observations suggest that anorexia-associated gastrointestinal motor dysfunctions are a consequence, not the cause of the generalized protein-calorie malnutrition associated with anorexia nervosa. The facts that motility in different parts of the gut is affected to different degrees and that gastric and duodenal muscle responds normally to exogenous stimulation argue against a generalized myogenic dysfunction and, rather, point to a reversible dysfunction of neural regulation.


Journal of Gastroenterology and Hepatology | 1996

Chronic liver disease in children on long‐term parenteral nutrition

Sudipta Misra; Marvin E. Ament; Jorge Vargas; Christopher Skoff; Laurie Reyen; Fay Herzog

Use of long‐term total parenteral nutrition (TPN) is often presumed to be associated with serious hepatic dysfunction. In this retrospective study, we reviewed the complete charts of patients who had received TPN for more than 2.5 years, starting in infancy or childhood, for evidence of liver dysfunction. There were 16 male and 10 female patients with a total of 254.5 patient years on TPN. Seventeen patients have been on TPN since birth or early infancy. Thirteen of 26 patients derive ≥90% of their calorie intake from TPN. Six patients had hepatomegaly; two of them also had splenomegaly. Twenty‐one patients had normal transaminases, nine have had past episodes of raised enzymes ranging from 2.5 to 7.5 times normal. Seventeen patients always had normal bilirubin levels, five had past episodes of hyperbilirubinaemia, while four patients had persistently raised bilirubin levels (range 1.5–20.7 g/dL). Alkaline phosphatase was normal for age in all patients except two. Hepatic synthetic function, as measured by albumin, pre‐albumin levels and prothrombin time, was within the normal range in all patients except one. Liver biopsies were performed in eight patients. Two biopsies showed cirrhosis, one showed chronic active hepatitis (CAH) with cholestasis, two patients had fibrosis, one showed cholestasis and two biopsies were normal. One patient with cirrhosis and one with CAH were positive for hepatitis C antibody. Another asymptomatic patient was positive for hepatitis B. Only the patient with CAH had hepatic decompensation. We conclude that clinical hepatic failure is uncommon in our group of patients on long‐term TPN for 2.5 years or more. Cirrhosis and fibrosis, when found, could not be solely attributed to TPN.


Transplant International | 2002

Late-onset bacteremia in uncomplicated pediatric liver-transplant recipients after a febrile episode

Ruben E. Quiros-Tejeira; Marvin E. Ament; Sue V. McDiarmid; Mary Gonzalez; Roberto Chong; Jorge Vargas; Martin G. Martin

Abstract The aim of this study was to analyze the incidence and risk factors of bacteremia after a febrilc episode in uncomplicated pediatric recipients more than 2 months after liver transplantation, which has not previously been studied. This cross‐sectional study was conducted over a 4‐year period. Patients with known risk factors for sepsis at the time of admission were excluded from the study. Seventy‐one patients were hospitalized on 128 occasions, with bacteremia occurring in the case of 11 admissions (8.6%). No laboratory tests were predictive of bacteremia. The bacteremic group most frequently presented with ill appearance (P<0.001), lethargy (P<0.01), decreased physical activity, and a history of early‐onset bacteremia after transplantation and segmental graft (P<0.05). This study identified a significant incidence of bacteremia in uncomplicated patients many months after liver transplantation.


The Journal of Pediatrics | 1986

Superior mesenteric artery stenosis: Cause of recurrent ischemic bowel syndrome in an infant

W.E. Berquist; A.S. Gomes; Marvin E. Ament; R.S. Sparkes; David L Diehl

Our patient demonstrates a very rare complication of virilization of the external genitalia in females with congenital adrenal hyperplasia. Because of the fusion of the labia and an extremely small urogenital sinus orifice at the perineum, urine refluxed into the vagina and into the miillerian ducts. For unexplained reasons, the path of least resistance for urine flow was through the uterus and into the left fallopian tube, leading to massive dilation of the fallopian tube. Because of reports of increased tumor risk in congenital adrenal hyperplasia, this mass was originally believed to represent an ovarian teratoma. 3,4 When urine reaccumulated after the initial surgery, despite catheterization of the vagina, separation of the labial fusion and distal vaginoplasty was performed to relieve urinary obstruction. A more complete vaginoplasty may be required later. Children with congenital adrenal hyperplasia who have small urogenital sinus openings with near total labial fusion should be evaluated for the need for prophylactic separation of the labia. Periodic ultrasound examinations for evidence of urinary reflux into the vagina and mfillerian ducts should also be considered. We recommend consideration of early surgery to relieve urinary obstruction.


The Journal of Pediatrics | 2004

Long-term parenteral nutritional support and intestinal adaptation in children with short bowel syndrome: A 25-year experience

Ruben E. Quiros-Tejeira; Marvin E. Ament; Laurie Reyen; Faye Herzog; Michelle Merjanian; Nancy Olivares-Serrano; Jorge Vargas


Hepatology | 1995

Choline deficiency: A cause of hepatic steatosis during parenteral nutrition that can be reversed with intravenous choline supplementation

A.L. Buchman; Mark Dubin; Adib A. Moukarzel; Donald J. Jenden; Margareth Roch; Kathleen M. Rice; Jeffrey Gornbein; Marvin E. Ament

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Jorge Vargas

University of California

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Joel D. Kopple

Los Angeles Biomedical Research Institute

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Laurie Reyen

University of California

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Margareth Roch

University of California

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