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Biomedical subjects

R J Shulman

Publications and source records attributed to R J Shulman.

At least 73 records · Page 4Linked to original sources
PubMed1986

Splanchnic bed vascular malformations and the development of portal hypertension.

The vascular lesions, angiomas, and arteriovenous malformations are known to be associated with a number of complications. These lesions, when present in the liver, may precipitate heart failure in infants. Recent reports suggest that although the prognosis is good for the majority of infants who survive the neonatal period, the lesions are capable of causing portal hypertension later in life. We have encountered three patients whose vascular lesions were in continuity with the portal circulation who subsequently went on to develop portal hypertension. One patient had angiomas of the liver, one splenic and colonic angiomas, and the third had diffuse arteriovenous malformations of the intestine. Data are presented and literature is reviewed, which suggest that any vascular lesion that is capable of substantially increasing portal blood flow may lead to the development of portal hypertension. The treatment of such lesions should be aggressive. If surgical management is not possible, alternative treatments such as embolization should be attempted early in order to increase the chance for successful therapy.

Arteriovenous Malformations↗
PubMed1986

Protein deficiency in premature infants receiving parenteral nutrition.

A classical finding of protein deficiency is hair depigmentation, or the flag sign. To determine the clinical conditions that predispose ill premature infants to the development of protein deficiency, we compared the clinical courses and nutritional histories of premature infants receiving parenteral nutrition who developed the flag sign (group F), with those of a matched control group (Group C). Occurrences of necrotizing enterocolitis (NEC) and consequent surgery were significantly higher in group F than in group C (p less than 0.002 and p less than 0.005, respectively). No differences were found in the mean (+/- SD) administration of amino acids (group F, 2.5 +/- 0.2 g X kg X day vs group C, 2.4 +/- 0.4) and total energy (83.4 +/- 13.4 kcal X kg X day vs 83.6 +/- 11.1, respectively). Mean serum albumin levels (2.6 +/- 0.4 g/dL vs 2.6 +/- 0.5, respectively) also were similar. Because infants in both groups received recommended amounts of protein, results suggest that infants who have NEC, and surgery as a consequence of NEC, require more protein than is presently recommended.

Enteral Nutrition↗
PubMed1986

Endoscopic detection of peptic ulcer disease in cystic fibrosis.

Abdominal pain is common among cystic fibrosis (CF) patients and may be caused by a variety of conditions. Although peptic ulcer disease (PUD) has not been emphasized as a common cause of abdominal symptoms in CF, the risk for the development of PUD may be increased because of abnormal physiology. Contrast radiography appears to be an especially inaccurate method to document PUD in CF because the duodenal mucosa typically appears nodular and distorted with poor definition of the mucosal folds. These findings may obscure or mimic PUD. The first endoscopic diagnosis of PUD is reported in a CF patient. Based on this case and a review of the literature, endoscopy is the procedure of choice for evaluation of a CF patient who is suspected of having PUD.

Adolescent↗
PubMed1986

Absorption and oxidation of glucose polymers of different lengths in young infants.

Because mucosal glucoamylase is most active against glucose polymers less than 10 glucose units in length, longer chain polymers may not be completely absorbed by young infants. In order to investigate this possibility, the absorption and oxidation of 13C-rich glucose, short-chain (3 to 8 glucose units in length) and long-chain (average length 43 units) glucose polymers (GP) were compared in 12 healthy, 1-month-old infants. Recovery of the GP and glucose in stool was measured by determining the 13C enrichment of stool. The oxidation of the GP was measured by tracing the increase in breath 13CO2 after GP were fed. Carbohydrate malabsorbed in the small bowel was assessed by measurement of breath H2, a gas formed from the fermentation of carbohydrate in the colon. Analysis of the infants' stools revealed that one infant excreted 9.7% of the dose of glucose, another 6.7% of the dose of short-chain GP, and five infants excreted 2.6 to 18.5% (mean 8.4%) of the dose of long-chain GP. The percent of the administered dose recovered in breath was similar among substrates (mean = 28.7% of the dose fed). A rise in breath H2 greater than 20 ppm was found in four of the 12 infants after the feeding of glucose, in five of 12 after the short-chain GP, and in six of 12 after the long-chain GP. None of the infants developed diarrhea. The results suggest that healthy young infants do not absorb long-chain GP as completely as they absorb short-chain GP.(ABSTRACT TRUNCATED AT 250 WORDS)

Glucans↗
PubMed1986

Evaluation of a pediatric multiple vitamin preparation for total parenteral nutrition in infants and children. I. Blood levels of water-soluble vitamins.

This study represents the first attempt to evaluate the response to the only intravenous vitamin preparation (MVI Pediatric) for infants and children receiving total parenteral nutrition. Eighteen preterm infants (group 1), 26 term infants and children receiving total parenteral nutrition for 2 to 4 weeks (group 2A), and eight infants and children receiving total parenteral nutrition for 3 to 6 months (group 2B) were studied. Term gestation infants and children up to 11 years of age received daily vitamin doses that approximated the 1974 Recommended Dietary Allowances and coincided with the 1975 American Medical Association Nutrition Advisory Group total parenteral nutrition dosage guidelines for children weighing more than 10 kg. Preterm infants received 65% of these dosages. RBC transketolase (vitamin B1), glutathione reductase (B2), and glutamic oxaloacetic transaminase (B6) activities were maintained at normal levels, and niacin levels were maintained within the reference range (7.1 +/- 0.32 micrograms/mL) in all study patients. Pantothenate, biotin, and ascorbate were maintained at reference levels in groups 2A and 2B. In group 1, ascorbic acid was increased significantly during treatment from 1.53 +/- 0.16 to 3.60 by seven days and to 2.54 +/- 0.62 by day 28 of treatment (reference normals = 0.99 +/- 0.1 mg/dL). RBC folate was maintained within the reference range of 411 +/- 76 pg/mL; however, pantothenate and biotin levels increased significantly to more than 2 SD above reference values during treatment, and vitamin B12 levels, which were above the reference range initially, were maintained at more than 2 SD above the reference range throughout treatment. The elevation in vitamin B12 was seen in both group 1 and 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1986

Evaluation of a pediatric multiple vitamin preparation for total parenteral nutrition. II. Blood levels of vitamins A, D, and E.

This study represents the first attempt to evaluate the American Medical Association Nutrition Advisory Group (NAG) recommendations for intravenous vitamin A, D, and E dosages for infants and children. Patients studied included 18 preterm infants (group 1) and 26 term infants and children (group 2A) receiving total parenteral nutrition for 2 to 4 weeks and eight infants and children receiving total parenteral nutrition for 3 to 6 months (group 2B). Term gestation infants and children up to 11 years of age all received the same dosages (those that were recommended by the NAG for children weighing more than 10 kg). Preterm infants received 65% of these doses. In group 1, cord blood alpha-tocopherol levels were less than 0.22 mg/dL in seven preterm infants (reference value = 0.29 +/- 0.04), but mean levels increased to 1.65 +/- 0.17 mg/dL after four days of treatment. Eight infants consistently received additional vitamin E orally (80 to 150 mg daily), and their levels increased to 2.18 +/- 0.26 mg/dL by four days of study and to 3.49 +/- 0.57 mg/dL after 3 weeks. Oral supplementation in the preterm infants appeared to be unnecessary because intravenous vitamins alone maintained levels above 1.1 mg/dL. In group 2, alpha-tocopherol levels were maintained within the reference range. Patients receiving lipid emulsions containing substantial quantities of alpha-tocopherol had significantly higher blood levels than patients receiving lipid emulsions containing little alpha-tocopherol (P less than .01). Mean 25-OH vitamin D levels were maintained above or within the reference range in groups 2A and 2B.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1985

Characterization and evaluation of immunochemical methods for the measurement of fecal alpha 1-antitrypsin.

Measurement of alpha 1-antitrypsin in feces has been proposed as a method of diagnosing a protein-losing enteropathy. This approach makes use of an endogenous marker rather than radioisotopically labeled materials such as 51CrCl3 or 131albumin to measure protein clearance. The validity of using fecal alpha 1-antitrypsin measurement as a reflection of protein loss through the gastrointestinal tract has been demonstrated by several investigators. The authors report here the characterization of excreted alpha 1-antitrypsin and an evaluation of the immunochemical methods used to measure this protein. They find alpha 1-antitrypsin to be excreted both as a protease-antiprotease complex and in a form that is relatively unaltered compared with serum alpha 1-antitrypsin. The proportion of alpha 1-antitrypsin excreted as a complex was found to vary from patient to patient. Formation of the protease-antiprotease complex was found to decrease the apparent alpha 1-antitrypsin concentration when radial immunodiffusion or immunonephelometry were used. The observed bias was greater for radial immunodiffusion. When these methods were applied to a newborn population at risk for necrotizing enterocolitis, radial immunodiffusion was found to have better sensitivity and a higher predictive value for a positive result than the nephelometric method. The use of fecal alpha 1-antitrypsin for diagnosis of protein-losing enteropathy appears to be best accomplished by radial immunodiffusion.

Electrophoresis, Polyacrylamide Gel↗
PubMed1985

Effect of infant age on aminopyrine breath test results.

UNLABELLED: The aminopyrine breath test has been used in adults as a measure of hepatic N-demethylase activity. In order to study maturational changes in enzyme function, 13C aminopyrine (2 mg/kg) was administered orally to infants (n = 16) between the ages of 1 and 38 wk. Breath samples were collected for 6 h after administration of the labeled aminopyrine for the measurement of 13CO2 enrichment. Using a number of different scoring methods to quantitate 13CO2 elimination of breath, demethylation of aminopyrine was found to be positively correlated to age. By 20 wk of age, some infants had rates of elimination similar to those measured in adults. Absorption was excluded as a limiting variable, because no improvement in oxidation rates was found when the aminopyrine was readministered as an intravenous bolus. Changes in nutritional status and route of feeding (enteral versus parenteral) did not prevent the effect of maturation on aminopyrine elimination. CONCLUSIONS: 1) maturational differences are seen in the metabolism of aminopyrine; 2) these differences may reflect immaturity of N-demethylase activity or diversion of the liberated formaldehyde into biosynthetic rather than oxidative pathways.

Age Factors↗
PubMed1984

Unusual appearance of Crohn's disease.

The association of perianal fistulas and Crohn's disease is well recognized. The appearance of lesions distant from the anal area is, however, uncommon. A young girl appeared with a history of weight loss and extensive mucocutaneous ulcerations. Diarrhea subsequently developed. Colonoscopy revealed friability, edema, and ulcerations. A crypt abscess was found in colonic biopsy specimens. Treatment with prednisolone acetate and sulfasalazine resulted in prompt improvement. A skin biopsy done initially and repeated colon biopsy three months later demonstrated granulomas, consistent with Crohn's disease. The literature regarding skin lesions in association with Crohn's disease is reviewed and the importance of recognizing the cutaneous manifestations of Crohn's disease is emphasized.

Child↗
PubMed1984

Rapid determination of whole-body bicarbonate kinetics by use of a digital infusion.

Accurate determination of substrate oxidation rates from breath 13CO2 levels often requires information on the bicarbonate status of the subject. We have developed a rapid method to obtain a complete set of bicarbonate kinetic parameters, prime bicarbonate pools with 13C, clamp breath 13CO2 levels rapidly and accurately with predetermined ranges, and provide a steady base-line enrichment of 13C for a subsequent substrate oxidation measurement. The method consists of administering NaH13CO3 intravenously as a combination of a bolus dose, an exponentially decreasing infusion, and a constant infusion. A Harvard model 2729 microprocessor-controlled syringe pump was modified for external control and coupled to a Hewlett-Packard HP-85 desk-top computer to deliver the complex infusion. An infusion algorithm that would rapidly attain and maintain an increase of 50% 13C enrichment of breath CO2 was derived by using the SAAM-27 program to interrogate a three-compartmental model of bicarbonate kinetics in normal, fasted, resting adult subjects. When the method was tested on five adult fasted subjects who had rested for 1.5 h, plateau enrichments were achieved within 10-20 min. The bicarbonate pool sizes and kinetic parameters obtained by compartmental analysis of their 13CO2 data were used to obtain a refined infusion protocol, which resulted in more rapid attainment of plateau enrichments. If carried out immediately before a substrate oxidation test, the method can provide a complete description of bicarbonate kinetics for use in the compartmental and noncompartmental analysis of substrate catabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Effect of different total parenteral nutrition fuel mixes on the body composition of infant miniature pigs.

At 10 d of age miniature pigs were randomized to receive either of two total parenteral nutrition fuel mixes; oral feedings were discontinued. Both groups received 170 kcal X kg-1 X d-1 and 11 g X kg-1 X d-1 of synthetic amino acids. Nonprotein energy was supplied as glucose in group A, whereas in group B, it was divided equally between glucose and fat. Blood samples were drawn on the second and eighth postoperative days for hematologic, biochemical, and hormonal measurements. On the ninth postoperative day, total body water was determined and the animals were killed for carcass analysis. The animals tolerated the intravenous nutrition without ill effects as indicated by both clinical and biochemical parameters. Group A had significantly elevated levels of insulin and a higher insulin/glucagon ratio than group B. Cortisol levels did not differ significantly between groups. Total body fat, nitrogen, ash, K, Na, Cl, Ca, and P were similar between groups. TBW was significantly greater in group A compared with group B. Extracellular space calculated from body Cl and plasma Cl was similar between groups.

Adipose Tissue↗
PubMed1983

Utilization of dietary cereal by young infants.

The direct demonstration of cereal utilization by 16 healthy 1-month-old infants was achieved by tracing the appearance in breath CO2 of carbon derived from the fed cereal. These oxidation rates were compared with rates obtained from the feeding of glucose and glucose polymers. Fermentation of unabsorbed carbohydrate by the colonic flora was assessed by measurement of breath H2. Stools from four infants were analyzed for the quantity of carbon that originated from the cereal. Oxidation rates were not significantly different (mean = 31.2% of the dose fed). Mean peak hydrogen production was 39.8, 29.1, and 18.6 ppm for cereal, glucose polymers, and glucose, respectively. Cereal carbon was detected in the stools of two infants (3.7% and 13.1% of the ingested load). We conclude that young infants can utilize cereal, although absorption is not always complete. Hydrogen production increases with carbohydrate complexity; participation of colonic bacterial fermentation increases the net absorption of cereal.

Breath Tests↗
PubMed1983

[13C]bicarbonate kinetics in humans: intra- vs. interindividual variations.

A comprehensive multicompartmental analysis of HCO-3 kinetics was carried out on five normal, resting, fasted adults on three separate occasions at 1-wk to 1-mo intervals to obtain a set of bicarbonate kinetic parameters and estimates of their inter- and intraindividual variations for use in the design and analysis of future nutrient oxidation studies. Following a rapid bolus of NaH13CO3 (10 mumol . kg-1 iv), the decay of 13C enrichment of breath CO2 could be described by a three-exponential decay process and a linearly time-dependent term that accounted for changes in the 13C enrichment of metabolic fuels. The data were fitted subsequently to a mammillary multicompartmental model that consisted of a central pool and two peripheral pools of 3,310, 3,490, and 8,070 mumol . kg-1 HCO-3-CO2. Labeled CO2 was eliminated from the central pool by respiratory and nonrespiratory routes at rates of 101 and 97 mumol . kg-1 . min-1, respectively. The within-subject and among-subject variances were similar for the amount of freely exchangeable bicarbonate (14,870 mumol . kg-1), CO2 output (101 mumol . kg-1 . min-1), bicarbonate flux (198 mumol . kg-1 . min-1), and the fraction of administered bicarbonate recovered in breath (0.51). Comparison of variances associated with the assignment of a population mean value to a new subject and the variance associated with the use of a value obtained in the same individual on another day indicated that there was no advantage to making a determination on an alternate day over using a population value. Efforts should be made to compile population values for bicarbonate kinetics in different age groups and metabolic, nutritional, and pathological states for use in interpretation of nutrient oxidation data.

Adult↗
PubMedDate not supplied

Fasting and cognitive function.

The effects of short-term fasting (skipping breakfast) on the problem-solving performance of 9 to 11 yr old children were studied under the controlled conditions of a metabolic ward. The behavioral test battery included an assessment of IQ, the Matching Familiar Figure Test and Hagen Central Incidental Test. Glucose and insulin levels were measured in blood. All assessments were made under fasting and non-fasting conditions. Skipping breakfast was found to have adverse effects on the children's late morning problem-solving performance. These findings support observations that the timing and nutrient composition of meals have acute and demonstrable effects on behavior.

Blood Glucose↗
PubMedDate not supplied

Effects of age, feeding regimen, and glucocorticoids on catecholamine and cortisol excretion in preterm infants.

BACKGROUND: The sympathoadrenal system is important in maintaining normal physiologic functioning in infants and increased output also can reflect stress. We sought to determine the effects of age, feeding regimen, and glucocorticoids on catecholamine and cortisol excretion in preterm infants and to assess whether a particular strategy of feeding enhanced sympathoadrenal development or was stressful. METHODS: Preterm infants (26-30 wk gestation; n = 171) were assigned randomly to begin trophic feedings from day 4 through 14 (trophic group) or to start feedings at day 15 (standard group) with feedings administered either by bolus every 3 hours (bolus) or continuously over 24 hours (continuous). At 10, 28, 40, 50, and 60 days of age, urine was collected continuously for 6 hours for measurement of catecholamines (norepinephrine, epinephrine, dopamine), cortisol, and creatinine. Data were available for 98 infants. RESULTS: Norepinephrine excretion increased with postnatal age. The increase with age was significantly greater in the trophic group compared with that in the standard group. Epinephrine excretion did not change with age, and there were no differences between trophic and standard groups. Dopamine excretion increased with age but was similar between trophic and standard groups (borderline significantly greater in the trophic group). Cortisol excretion increased with age and also was similar between trophic and standard groups. There was no effect on catecholamine or cortisol excretion of bolus vs continuous feedings, antenatal or postnatal corticosteroids, gestational age at birth, age at which full feedings were attained, or use of human milk compared with preterm formula. CONCLUSIONS: The greatest determinant of catecholamine and cortisol excretion is postnatal age. Feeding method, type of feeding, and glucocorticoid administration in the amounts customarily used have little significant effect on catecholamine or cortisol excretion. The apparent link between early feeding and norepinephrine (and possibly dopamine) excretion warrants further investigation.

Age Factors↗