Biomedical subjects

Devendra I Mehta

Publications and source records attributed to Devendra I Mehta.

4 recordsLinked to original sources

PubMed2006

Pepsin, a reliable marker of gastric aspiration, is frequently detected in tracheal aspirates from premature ventilated neonates: relationship with feeding and methylxanthine therapy.

OBJECTIVES: To determine the frequency of pepsin detection in tracheal aspirate (TA) samples of mechanically ventilated premature neonates and its association with feedings and methylxanthine therapy. PATIENTS AND METHODS: Serial TA samples (days 1, 3, 5, 7, 14, 21, 28 and >28 days) were collected from premature neonates receiving ventilatory support. An enzymatic assay with a fluorescent substrate was used to detect pepsin. Pepsin was also measured in 10 serum samples collected in conjunction with the TA samples from 8 neonates. RESULTS: A total of 239 TA samples was collected from 45 premature neonates (mean birth weight, 762 +/- 166 g; mean gestational age, 25.5 +/- 1.5 wk). Pepsin was detectable in 222 of 239 TA samples (92.8%) and in none of the serum samples. Pepsin was significantly lower on day 1 (mean, 170 +/- 216 ng/mL) when compared with all other time points (P < 0.05). Mean concentration of pepsin was significantly lower when infants were unfed (265 +/- 209 ng/mL) compared with levels during feeding (390 +/- 260 ng/mL, P = 0.02). The mean level of pepsin was significantly higher in infants during xanthine therapy (419 +/- 370 ng/mL) compared with no xanthine therapy (295 +/- 231 ng/mL, P = 0.037). CONCLUSION: Pepsin, a marker of gastric contents, was detected in more than 92% of TA samples from premature infants on mechanical ventilation. The level of pepsin was higher in fed infants when compared with unfed infants. Xanthine therapy was also associated with increased pepsin in TA samples. Chronic aspiration of gastric contents may worsen lung disease in premature infants.

Aging↗

PubMed2004

Cytokine release, pancreatic injury, and risk of acute pancreatitis after spinal fusion surgery.

Acute pancreatitis after posterior spinal fusion in children is associated with high intraoperative blood loss. Inflammation, oxidative stress, and pancreatitis markers were assessed during this period. Five of the 17 patients studied developed acute pancreatitis 3-7 days after surgery. Intraoperative blood loss (4850 +/- 2315 vs 1322 +/- 617 ml) and peak tumor necrosis factor alpha levels (15.29 +/- 5.3 vs 8.27 +/- 4.6 pg/ml) in the immediate postoperative period were significantly higher in these five patients than in controls, respectively. No differences were noted in serum interleukin 8, interleukin 6, pancreatis-associated protein, or urine malondialdehyde levels. Urine trypsin-associated peptide, elevated initially in all patients, was significantly higher in the acute pancreatitis group at diagnosis. Length of stay was significantly longer in the acute pancreatitis group. Greater blood loss and peak tumor necrosis factor alpha are associated with subsequent risk of acute pancreatitis, suggesting a role of ischemia-reperfusion injury.

Acute Disease↗

PubMed2004

Gastrointestinal tract.

The developing gastrointestinal tract from conception to adolescence is in constant direct interaction with an increasingly complex environment. This sets up the potential for unrecognized acute as well as chronic disorders, some of which may be difficult to pinpoint in a developing infant and child, given the wide variations that exist. It is startling to note how early some environmental toxins can come into contact with the developing human, where vulnerability may be heightened and maturation of detoxifying pathways may be incomplete. Although the complex process of recognizing, detoxifying, and avoiding the toxic substance by the body has presumably evolved over a substantial period of time, in this rapidly changing world, the array of novel toxins that make their way into the gastrointestinal tract is increasing. There remain many gaps in understanding the effects of environmental toxins on all of the developmental stages from conception to adolescence. Although threshold levels have typically been derived from adult or animal data, factors such as size, relative differences in consumption in proportion to size especially in infancy, and variable physiologic maturation of metabolic pathways are not well understood. The vulnerability may be further accentuated by physical factors that alter with maturity, such as permeability and critical times during organogenesis or organ maturation. Also of concern is how little is known about low-dose, long-term exposure, as well as any interplay with common illnesses. This article focuses on environmental toxins that have been shown to have toxic effects on the gastrointestinal tract.

Child↗

PubMed2003

Short-term effect of epidermal growth factor on glucose uptake in endoscopic biopsies.

Epidermal growth factor (EGF) up-regulation of glucose absorption via increased Na+/glucose co-transporter (SGLT-1) activity has previously been described in rabbit jejunal brush-border membrane and in differentiated Caco-2 cells. The goal of the present study was to assess the in vitro effect of EGF (200 ng/ml) on glucose uptake in human mucosal specimens, and we describe a simple procedure that uses endoscopic biopsies for short-term gludose uptake measurements. Uptake values for the EGF-treated biopsies ranged from 2.7 to 29.0, with a mean uptake of 10.65, while uptake values for the untreated biopsies ranged from 0.9 to 17.5, with a mean uptake of 7.99 (P < 0.05, paired t test). This early effect of EGF on human enterocytes may have important therapeutic implications. A role in increasing the rate of internal rehydration is suggested.

Adolescent↗