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Biomedical subjects

A L Buchman

Publications and source records attributed to A L Buchman.

At least 37 records · Page 2Linked to original sources
PubMed1999

The effect of arginine or glycine supplementation on gastrointestinal function, muscle injury, serum amino acid concentrations and performance during a marathon run.

Gastrointestinal bleeding and increased intestinal permeability have been observed in marathon runners. We sought to determine if L-arginine would be useful for prevention of these complications. Twenty-three runners were randomized to receive L-arginine (A) or glycine (placebo) (G), 10 grams 3 times daily for 14 days prior to the 1997 Houston-Methodist Marathon. Serum, stool hemoccults and lactulose:mannitol permeabilities were obtained at baseline, immediately after completion of the marathon and approximately 48 hours later. Runners rated their symptoms of nausea and vomiting, belching and indigestion, abdominal pain and bloating, diarrhea, and extremity pain on a 1-5 scale of increasing severity. The L:M was unchanged in either group during the three collections. Occult bleeding occurred in 8%/20% in A and G groups, respectively, p = NS) immediately post-marathon. No runners had occult bleeding 48 hours post-race. Gastrointestinal symptom scores were minimal to nonexistent. Extremity pain scores were similar for groups A and G (2.1+/-1.4 and 2.8+/-1.6, respectively, (p = NS). Fluid intake was similar between both groups (1875+/-1547 vs. 1506+/-970 ml, p = NS). Serum amylase was normal at baseline and remained virtually unchanged. Serum lipase was normal at baseline and immediately post-race in both groups, but increased at 48 hours post-race (82.2+/-34.3 to 121.5+/-53.3 mg/dl [A], p = 0.02 and 114.3+/-55.7 to 181.9+/-162.2 mg/dl [G], p = 0.09). CPK increased significantly and similarly in both groups immediately post-race, and even more dramatically 48 hours post-race (130.3+/-130.8 to 738.8+/-902.9, p = 0.007 to 1966.5+/-3.166.0 mg/dl [A] and 140.9+/-77.9 to 863.0+/-772.3, p = 0.003 to 5619+/-10636.8mg/dl [G]). Modest post-race decreases were seen in most serum amino acids in both groups. Finish times were longer than predicted (23+/-21 and 9+/-7 min for A and G groups, respectively, p = 0.049). Our study failed to show a clear benefit of arginine supplementation for the prevention of intestinal ischemia/reperfusion injury associated with endurance running, but either a detrimental affect on performance with arginine, or enhanced performance with glycine. Skeletal muscle injury was unaffected by arginine or glycine supplementation. The delayed increase in serum lipase suggests mild pancreatic injury, affected by either arginine or glycine supplementation.

Adult↗
PubMed1999

Plasma free, phospholipid-bound and urinary free choline all decrease during a marathon run and may be associated with impaired performance.

BACKGROUND: Previous investigations have shown that plasma free choline decreases during long distance running. OBJECTIVE: This study was undertaken to determine if body choline status changes during a marathon run and whether performance is thereby adversely affected. DESIGN: Twenty-three accomplished marathon runners 25 to 49 years of age were studied before and after the 1997 Houston-Methodist Marathon. Fasting blood and five-hour urine samples were obtained in the morning, 14 days prior to the race, immediately after the race and approximately 48 hours after completion of the race. Runners were asked to predict their finish times two weeks prior to the race. Performance was indicated by the ratio of predicted to actual time. RESULTS: Both plasma free and phospholipid-bound choline concentrations as well as urinary free choline concentration decreased immediately following the race (19.2+/-4.5 to 14.6+/-4.2 nmol/mL, p=0.005, and 2565.2+/-516.4 to 2403.4+/-643.0 nmol/mL, p=0.068, respectively) and, except for the phospholipid-bound choline, rebounded towards baseline after 48 hours (15.6+/-3.2 and 2299.9+/-426.7 nmol/mL), although plasma concentrations remained significantly below baseline. Plasma free and phospholipid-bound choline concentrations were significantly correlated (r=0.46, p=0.0001), although urinary free choline concentration was not correlated with either. There was no correlation between plasma free, phospholipid-bound or urinary free choline concentration and actual finish time or the ratio of predicted to actual finish time. However, the percent decrease in urinary free choline concentration was significantly correlated with the ratio of predicted to actual time (r=0.47, p=0.036). No relationship was seen between this ratio and the percent decrease in either plasma free or phospholipid-bound choline concentrations immediately after the race. CONCLUSION: Our finding of both decreased free and phospholipid-bound choline suggests the decrease in choline status is related to accelerated choline metabolism or enhanced choline uptake by tissues rather than decreased hepatic choline release. The role of choline supplementation during endurance running requires further investigation.

Adult↗
PubMed1999

Bones and Crohn's: problems and solutions.

Inflammatory bowel disease may manifest in various extra intestinal manifestations. Osteopenia and various arthropathies may be debilitating. These may be related to the disease itself, patient genetics, lifestyle, or disease treatment. Calcium and vitamin D malabsorption, vitamin K deficiency, malnutrition, corticosteroid and other immunosuppressive medications, smoking, lack of exercise and postmenopausal state may all play important roles. Treatment may be undertaken to correct nutrient deficiencies, inhibit bone resorption and increase bone formation.

Arthritis↗
PubMed1998

The effect of a marathon run on plasma and urine mineral and metal concentrations.

BACKGROUND: Little data exist on the requirements of trace metals and minerals for endurance athletes. Changes in body status of these elements must be examined before specific nutritional recommendations can be made. This study was designed to determine whether a marathon run was associated with changes in serum and urine metal and mineral concentrations. METHODS: Forty subjects who planned to complete the 1996 Houston-Tennaco marathon were recruited. Subjects had blood and urine samples collected 2 weeks prior to the race and immediately following the race. Blood and urine specimens were analyzed for copper, iron, magnesium and zinc concentrations. Blood was also analyzed for calcium concentration and ceruloplasmin activity. RESULTS: Twenty-six subjects (24 male, 2 female) completed the marathon. Finish times varied between 2 hours 43 minutes and 5 hours 28 minutes. There was no significant change in serum calcium, copper or zinc concentrations or ceruloplasmin activity. Serum and urine magnesium concentration decreased significantly (19.55+/-1.73 to 16.55+/-1.53 ppm, p=0.00001; 34.02+/-8.64 to 21.80+/-12.24 ppm, p=0.003, respectively). Serum iron concentration increased significantly (1.06+/-0.48 to 1.35+/-0.42 ppm, p=0.006), while urine copper and iron concentrations were below the limits of detection, zinc concentration did not change. CONCLUSIONS: Serum and urinary magnesium concentrations decrease during endurance running, consistent with the possibility of magnesium deficiency. This may be related to increased demand in skeletal muscle. Serum iron concentration increases, possibly related to tissue injury. The exact etiology for these observations, as well as their clinical significance, requires further investigation.

Calcium↗
PubMed1996

Glutamine: is it a conditionally required nutrient for the human gastrointestinal system?

Glutamine is a nonessential amino acid which can be synthesized from glutamate and glutamic acid by glutamine synthetase. It is the preferred fuel for the rat small intestine. Animal studies have suggested both glutamine-supplemented parenteral nutrition and enteral diets may prevent bacterial translocation. This effect is thought to be modulated via the preservation and augmentation of small bowel villus morphology, intestinal permeability and intestinal immune function. The existing data are less compelling in humans. It remains unclear what, if any, intestinal deficits actually occur in humans during provision of exclusive parental nutrition. Furthermore, the clinical significance of these changes is largely undefined in humans. The existing data on the use of parenteral and enteral glutamine for the purpose of preserving intestinal morphology and function, and the prevention of bacterial translocation in humans are reviewed. Pertinent animal data are also described.

Animals↗
PubMed1996

The demise of modern medicine and gastroenterology.

A country that once led technological development in health care now leads the charge back to the cave, from which it took mankind 2 million years to emerge. The problems in U.S. health care are not simple. Therefore, there are no simple solutions. True health-care reform can be accomplished only via improved and unbiased public education, identification of the role for primary care, and the need for sub- and sub-subspecialties. Government has an important role, but even more importantly, as a nation, our priorities for rewards require careful reevaluation. Suppliers and consumers must sit down at the same table, realizing that basic health care is not responsive to the usual supply and demand theories proposed by economists. Only then can health care reform be considered a positive change.

Economics, Medical↗
PubMed1996

Eosinophilic gastrojejunitis associated with connective tissue disease.

We report a case of eosinophilic enteritis associated with an ill-defined connective tissue disorder. The case was complicated by intestinal perforation and managed successfully without surgical intervention. No peripheral blood eosinophilia was present. Histologic examination of an intestinal biopsy revealed bands of eosinophils and mast cells at the base of the crypts with limited chronic inflammatory cell infiltrate.

Connective Tissue Diseases↗
PubMed1996

Vitamin supplementation in the elderly: a critical evaluation.

Routine vitamin supplementation for the elderly has been advocated by many. Specific vitamin deficiencies are rare in free-living elderly, but are not uncommonly encountered in hospitalized and institutionalized patients. Deficiency may result from interactions with medications or overall poor dietary intake. Low blood or plasma vitamin concentration is not necessarily indicative of a deficient state. Specific vitamin supplements are useful in the treatment and prevention of a deficient state. However, there is little, if any benefit from supplementation for reasons other than replacement therapy. The incidence and clinical symptoms of thiamine (vitamin B1), riboflavin (B2), pyridoxine (vitamin B6), vitamin B12, C, D, folate, niacin, vitamin A, E, beta carotene, and K deficiency and their treatment and prevention in the elderly are discussed.

Aged↗
PubMed1995

Excessive urinary oxalate excretion occurs in long-term TPN patients both with and without ileostomies.

OBJECTIVE: To determine if excessive oxalate and deficient citrate excretion were associated with TPN-associated nephropathy. DESIGN: Crossectional cohort. SETTING: Outpatient clinic. SUBJECTS: Twenty-five patients (15 males, 10 females) aged 51 +/- 17 (mean +/- SD) years who had received home total parenteral nutrition (TPN) for 10 +/- 4 years. Fifteen subjects had ileostomies (Group A) and 10 had functional colons (Group B). OUTCOME MEASURES: Glomerular filtration rate (GFR), tubular reabsorption of phosphate (TRP), urinary oxalate and citrate excretion. RESULTS: The mean GFR was 68.1 +/- 34.5 ml/minute/1.73 m2 and did not differ between Groups A and B. The mean TRP was 65.0 +/- 32.2% for Group A and 80.5 +/- 16.0% for Group B. The difference was not statistically significant. Urinary oxalate and citrate excretion were 40.2 +/- 30.2 and 324.4 +/- 239.0 mg/day respectively for Group A, and 63.2 +/- 34.2 and 474.8 +/- 936.3 respectively for Group B. The differences were not statistically significant. Thirty-eight percent (38%) of patients with ileostomies and 78% of patients without ileostomies had excessive urinary oxalate excretion (> 40 mg/day). Fifteen percent (15%) of patients with ileostomies and 50% of patients without ileostomies had decreased urinary citrate excretion (< 140 mg/day). CONCLUSIONS: Increased endogenous oxalate production may occur in patients receiving long-term TPN.

Absorption↗