Biomedical subjects

J N Udall

Publications and source records attributed to J N Udall.

77 records · Page 5Linked to original sources

PubMedDate not supplied

Plasma immunoreactive-trypsin(ogen) levels during development.

We previously showed that the uptake of intact trypsin from the intestine of suckling animals was greater than that of weaned animals. To extend these studies, we measured plasma cationic immunoreactive-trypsin(ogen) in human subjects aged 3 days to 43 years. In agreement with the observation of other investigators, we found that the concentration of cationic immunoreactive-trypsin(ogen) was significantly increased in 3-day-old infants compared with other age groups. None of the cationic immunoreactive-trypsin in adult samples was bound to alpha 1-antitrypsin, whereas 28% of cationic immunoreactive-trypsin in infant samples was bound to alpha 1-anti-trypsin.

Adolescent↗

PubMedDate not supplied

Three-in-one parenteral nutrition: a safe and economical method of nutritional support for infants.

The medical records of 20 infants under 1 year of age who received parenteral nutrition (PN) for a minimum of 1 week were reviewed. Patients were divided into two groups based on the method of PN administration. One group received PN by the traditional two-plus-one method where lipid emulsion is given separately from the dextrose-amino acid mixture. The second group received PN by the three-in-one method where lipid emulsion is admixed with the dextrose and amino acids. There were no statistically significant differences between the two groups in the amount of calories, lipid, dextrose, protein, calcium, and phosphorus received per kg of body weight. Average daily weight gain was not statistically different, and no obvious trends were noted in serum biochemical parameters between the two groups. Average total PN days for the groups (13 +/- 7 days for the two-plus-one group vs 39 +/- 35 days for the three-in-one group) were significantly different (p less than 0.05). A cost comparison of the two methods of PN administration indicated that the two-plus-one method costs our hospital $11.78 more per day than the three-in-one solution. We conclude that the three-in-one method of PN administration is safe, efficacious, and cost effective for infants under 1 year of age.

Cost-Benefit Analysis↗

PubMedDate not supplied

Use of infliximab in pediatric patients with inflammatory bowel disease.

BACKGROUND: The concentration of tumor necrosis factor, a proinflammatory cytokine, is increased in the gastrointestinal mucosa of patents with active Crohn's disease (CD) and ulcerative colitis (UC). Neutralization of tumor necrosis factor decreases the mucosal inflammatory response of adults with CD. Little information is available on the use of monoclonal antibody to tumor necrosis factor (infliximab) in children and adolescents with CD or UC. OBJECTIVE: To evaluate the clinical response and side effects of patients to infliximab. METHODS: A retrospective review of data regarding 18 pediatric and adolescent patients with active CD (n = 15) and UC (n = 3) poorly controlled with conventional therapy. All patients received one to six intravenous infusions of infliximab 5 mg/kg, while receiving their usual medications. RESULTS: All patients experienced clinical improvement, including decrease in the frequency of stooling and resolution of extraintestinal symptoms such as arthropathy, malaise, and skin manifestations after treatment with infliximab. All but one patient had a documented decrease in the erythrocyte sedimentation rate. Prednisone dosage was tapered in all but two patients, and discontinued in seven patients. Intravenous infusion of infliximab was well tolerated. One patient developed a rash several days after the infusion. A patient who received six infliximab infusions developed recurrent Staphylococcus aureus infections, as well as septic arthritis and chronic osteomyelitis during the follow-up period, raising the issue of the long-term safety of infliximab. CONCLUSIONS: Treatment of our patients with refractory CD and UC with infliximab was associated with remarkable clinical improvement. Although the drug may have an important role in their management, further assessment of long-term safety and efficacy is needed.

Adolescent↗

PubMedDate not supplied

Regulation of tumor necrosis factor secretion in leukocytes from alpha-1-antitrypsin deficient humans.

Alpha-1-antitrypsin (AT) is one of several alpha-globulins which have been shown to be inhibitors of human peripheral blood monocyte TNF secretion in vitro. AT deficiency states exist, within which individuals of either the PiSS or PiZZ phenotype have reduced hepatocyte and mononuclear phagocyte AT secretion when compared to normal PiMM subjects. Here we have compared the capacity of peripheral blood monocytes of all three phenotypes to respond to both enhancers and inhibitors of TNF secretion. All monocytes exposed to lipopolysaccharide (LPS), interferon-gamma (IFN-gamma) and endotoxin, PGE2, transforming growth factor-beta 1, whole plasma alpha-globulins, purified AT and IL-6 responded equally with respect to the secretion of TNF. Our findings show that the regulation of TNF secretion in leukocytes from AT deficient humans is normal and suggest that defective AT secretion alone does not result in the aberrant regulation of TNF secretion.

Adult↗

PubMedDate not supplied

Endopeptidase inhibition and intestinal antigen processing in mice.

The role of gastrointestinal digestive processes in the systemic availability of ingested protein antigens was examined by feeding the trypsin inhibitor aprotinin intragastrically to mice and measuring uptake of ovalbumin and 14C-polyethylene glycol (MW 4000) from the gastrointestinal tract. Trypsin and chymotrypsin activities in the intestinal lumen were significantly reduced by aprotinin feeding. Aprotinin slowed stomach emptying, but radioimmunoassays for immunoreactive ovalbumin in the serum of mice prefed aprotinin showed 12-fold elevations within 1 hr after ovalbumin feeding. Uptake of a nonmetabolized macromolecular probe, 14C-polyethylene glycol-4000, increased less than two-fold when fed with aprotinin under the same conditions, indicating that the increased uptake of immunoreactive ovalbumin was not due to changes in intestinal permeability. The results show that inhibition of luminal proteolysis caused significant increases in the serum concentration of immunoreactive ovalbumin, indicating that acute inhibition of luminal proteases permits larger quantities of relatively intact protein to interact with mucosal absorptive surfaces. These results support the hypothesis that pancreatic proteases modulate antigen absorption from the lumen in adult animals.

Animals↗