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Biomedical subjects

P Puri

Publications and source records attributed to P Puri.

At least 199 records · Page 11Linked to original sources
PubMed1995

Intraoperative evaluation of extent of aganglionosis by a rapid acetylcholinesterase histochemical technique.

Using a supplemental oxidation step, the authors modified the acetylcholinesterase (AChE) histochemistry technique of Karnovsky and Roots to produce staining of cholinergic nerve fibers in 10 minutes rather than in 2 hours, as required with the conventional AChE technique. They examined seromuscular intestinal biopsy specimens taken at three levels (aganglionic, transitional zone, ganglionic) from 10 patients during pull-through operations for Hirschsprung's disease, using the rapid AChE technique in addition to H&E staining. Using the acetylcholinesterase technique, the hypertrophic nerve trunks in the aganglionic segment and ganglion cells in the ganglionic segment stained strongly and were easily noticeable. The authors believe that the rapid AChE technique is a simple and reliable method for intraoperative evaluation of the extent of the aganglionic segment, because it provides quicker and more accurate identification of ganglion cells and hypertrophic nerve trunks in the space between the longitudinal and circular muscle layers of the bowel wall.

Acetylcholinesterase↗
PubMed1995

Intestinal neuronal dysplasia is a possible cause of persistent bowel symptoms after pull-through operation for Hirschsprung's disease.

The proximal margin of the resected bowel specimens from 33 consecutively treated patients undergoing a definitive pull-through operation for Hirschsprung's disease (HD) and control specimens consisting of suction rectal biopsy specimens obtained from 24 age-matched patients evaluated for constipation (and proven not to have HD) were examined using conventional H&E staining and acetylcholinesterase (AChE) histochemistry. Complete resection of the aganglionic segment was confirmed in 31 patients. In one patient, the proximal margin was found to be aganglionic; in another, the proximal margin was in a transitional zone. In both patients, frozen sections at the time of surgery were interpreted as having ganglion cells. In 10 of 31 patients, intestinal neuronal dysplasia was demonstrated in the proximal margin of the resected bowel. The abnormalities included hyperplasia of the submucous plexus, giant ganglia (with > 7 ganglion cells), and ectopic ganglion cells (all 10 patients) and increased AChE activity in the lamina propria (5 patients). All ten patients with IND had persistent bowel problems after the definitive operation for HD, such as enterocolitis, soiling, or constipation. Only four of the other 21 patients had persistent bowel symptoms. This study suggests that IND is commonly associated with HD. It also emphasizes the importance of histochemical examination of the resected segment to predict postoperative bowel function in patients with HD.

Acetylcholinesterase↗
PubMed1995

Absence of NADPH-diaphorase activity in internal anal sphincter (IAS) achalasia.

We studied the internal anal sphincter (IAS) muscle from 10 patients with achalasia and five normal controls using histochemical staining for NADPH-diaphorase and acetylcholinesterase (AChE). Normal control IAS muscle contained occasional AChE-positive nerve fibers, whereas IAS achalasia specimens demonstrated prominent AChE-positive nerve fibers in muscle layers. NADPH-diaphorase activity was strongly expressed in nerves in the normal IAS muscle but was absent or scanty in the muscle of patients with IAS achalasia. Our findings of increased AChE-positive nerves and the absence of NADPH-diaphorase activity taken in conjunction with reports of abnormal peptidergic innervation indicate that complex neural abnormalities occur in IAS achalasia. The primary event remains obscure, but it is possible that a single defect, such as nitrergic nerve depletion, may lead to compensatory changes in the other nerve fibers.

Acetylcholinesterase↗
PubMed1995

Immunochemical characterization of neural cell adhesion molecule (NCAM), nitric oxide synthase, and neurofilament protein expression in pyloric muscle of patients with pyloric stenosis.

The etiology of hypertrophic pyloric stenosis (HPS) is not known. We made an immunocytochemical examination of pyloric muscle from 18 patients with HPS and 10 controls using specific monoclonal antibodies to neural cell adhesion molecule (NCAM) as well as neurofilament protein and NADPH-diaphorase histochemistry. In HPS, bundles of hypertrophic muscle fibers expanded the circular muscle layer. The longitudinal muscle also appeared hypertrophic but to a less marked degree. The most striking difference between HPS and the control tissues was that NCAM, NADPH-diaphorase, and neurofilament protein immunoreactive fibers were absent or markedly reduced within the hypertrophied circular and longitudinal musculature. In contrast, NCAM, NADPH-diaphorase, and neurofilament protein immunoreactivity was preserved in the myenteric plexus where nerve fibers and ganglion cells were stained. The lack of expression of NCAM, NADPH-diaphorase, and neurofilament protein on nerve fibers within the circular and longitudinal muscle in patients with pyloric stenosis suggests that the smooth muscle is not innervated in this condition.

Amino Acid Oxidoreductases↗
PubMed1995

Abnormal innervation and altered nerve growth factor messenger ribonucleic acid expression in ureteropelvic junction obstruction.

The pathophysiology of ureteropelvic junction obstruction is unknown. Using specific antibodies, we studied specimens from 35 cases of ureteropelvic junction obstruction and 32 of normal ureteropelvic junction by immunohistochemistry using protein gene product 9.5 (a general neuronal marker), S100 (a supporting cell marker), synaptophysin (a neuromuscular junction marker) and nerve growth factor receptor. Nerve growth factor expression was examined at the messenger ribonucleic acid (mRNA) level using reverse transcription-polymerase chain reaction technique in 11 ureteropelvic junction obstruction specimens and 7 controls. The most striking finding was the marked reduction of protein gene product 9.5, synaptophysin and nerve growth factor receptor staining positive nerve fibers in the muscle layers of ureteropelvic junction obstruction compared to the normal ureteropelvic junction. Supporting nerve cell fibers (S100) were preserved in cases of ureteropelvic junction obstruction and normal ureteropelvic junction. A significantly less intense signal for nerve growth factor mRNA was found in the ureteropelvic junction obstruction specimens compared to normal ureteropelvic junction. These findings suggest that defective innervation may have an important role in the pathogenesis of ureteropelvic junction obstruction, and decreased nerve growth factor mRNA expression may be important in the etiology of ureteropelvic junction obstruction.

Base Sequence↗
PubMed1995

Serum intercellular adhesion molecule (ICAM-1), a marker of renal scarring in infants with vesico-ureteric reflux.

OBJECTIVE: To determine if serum intercellular adhesion molecule (ICAM-1) levels correlate with renal scarring in children with vesico-ureteric reflux (VUR). PATIENTS AND METHODS: Serum ICAM-1 levels were measured in 81 children (29 boys and 52 girls, age range 2 months-13 years) with VUR using an enzyme-linked immunosorbent assay (ELISA) and compared with levels in a control group of 24 children (16 boys and eight girls, age range 2 days-13 years) with no urological abnormalities. RESULTS: The mean serum ICAM-1 level in the control group was 202 +/- 79 ng/mL (mean +/- 1 SD) compared with 347 +/- 96 ng/mL in children with VUR (P < 0.001). Fifteen of 26 children under 2 years of age demonstrated renal scarring while 18 of 44 children older than 2 years exhibited renal scarring. The mean serum ICAM-1 level in patients who were < 2 years of age and had renal scarring was 408 +/- ng/mL, significantly higher than in those who had no renal scarring (296 +/- 68 ng/mL, P < 0.01). In contrast, there was no difference in serum ICAM-1 levels in patients > 2 years of age with or with no renal scarring (353 +/- 87 and 325 +/- 91 ng/mL, respectively). CONCLUSION: Serum ICAM-1 levels are significantly higher in children with VUR and may represent a valuable marker of tubular damage in younger children with VUR.

Adolescent↗
PubMed1995

Endoscopic treatment of primary vesicoureteric reflux in infants by subureteric injection of polytetrafluoroethylene. A 9-year follow-up.

Fifty-two infants (75 ureters) with primary high-grade vesicoureteric reflux (VUR) treated endoscopically by subureteric injection of Polytef paste (STING) were followed up for 1-9 years. There were 30 boys and 22 girls and their ages ranged from 2 to 12 months. Forty-five percent of ureters had grade III VUR, 40% had grade IV and 15% had grade V VUR. Reflux ceased in 49 (65%) ureters after a single injection. Twenty-four percent of ureters in this series required more than one injection of Polytef paste to correct VUR. STING failed to correct VUR in 3 (4%) ureters. Eighty percent of the 49 ureters corrected after a single injection of Polytef required < 0.2 ml of paste per ureter to correct reflux. Ninety-three percent of ureters continue to show absence of VUR 1-9 years after endoscopic correction. Three of the 5 recurrences were only of grade I or grade II severity and required no treatment. No untoward effects were seen in these children with the use of Teflon as an injectable biomaterial. This day care procedure is simple, safe and effective in correcting high grades of reflux in infants.

Endoscopy↗
PubMed1995

Subureteric Teflon injection (STING). Results of a European survey.

Subureteric Teflon injection (STING) has been successfully used by several investigators for treating vesicoureteric reflux (VUR) in children. This multicentre European survey reviews the results of STING in 6,216 ureters. Twenty-two paediatric surgeons/urologists from 18 centres in Europe answered an enquiry regarding their experience with STING in the treatment of VUR. 6,216 refluxing ureters were injected with Polytef paste in 4,166 children during 1984-1990. There were 975 boys and 3,191 girls. Their ages ranged from 2 months to 14 years (mean 5.1 years). The reflux was grade I in 4.4% of ureters, grade II in 36.1%, grade III in 40.2%, and grades IV and V in 19.3% of ureters. All patients were followed up for periods ranging from 3 months to 81/2 years and 90% were followed up for more than 2 years. 76.3% of all ureters stopped refluxing after a single injection of Teflon paste, cure rate increased to 84.9% after a second injection. A further 10.2% of refluxing ureters showed significant improvement in the grade of reflux after a single injection and needed no further treatment. 1.3% of ureters were cured after a third or fourth injection. Failure to correct or improve VUR was seen in 224 ureters (3.6%), necessitating reimplantation. Twenty ureters (0.32%) developed vesicoureteric junction obstruction following STING and these were reimplanted without difficulty. Results of this multicentre survey confirm that STING is an effective day care procedure for treatment of all grades of VUR. 95% of all ureters were cured or showed significant improvement after two injections of Teflon paste.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Lack of expression of NADPH-diaphorase and neural cell adhesion molecule (NCAM) in colonic muscle of patients with Hirschsprung's disease.

The authors studied expression of NADPH-diaphorase and NCAM in colon from 16 patients with Hirschsprung's disease (HD) and eight age-matched controls, using immunohistochemical techniques. Myenteric ganglia in the ganglionic bowel and hypertrophic nerve trunks in the aganglionic bowel displayed strong NADPH-diaphorase and NCAM reactivity. Quantitative assessment of immunoreactivity in colonic muscle demonstrated a selective absence of NADPH-diaphorase and NCAM-positive nerve fibers in the circular as well as longitudinal muscle of aganglionic bowel, whereas these immunoreactive nerve fibers were present in abundance in the muscle of ganglionic colon of HD patients as well as in the colon of controls. The lack of expression of NCAM on nerve fibers within the muscle of HD patients suggests a developmental abnormality of innervation of the muscle, and the selective absence of NADPH-diaphorase-positive nerves in the muscle is most likely responsible for the spasticity of the aganglionic segment.

Cell Adhesion Molecules, Neuronal↗
PubMed1994

The influence of trisomy 21 on outcome in children with Hirschsprung's disease.

The association of Hirschsprung's disease (HD) and trisomy 21 has been well recognised. Seventeen (13%) of 135 patients presenting with HD between 1975 and 1992 had trisomy 21. Nine (53%) presented in the neonatal period, with intestinal obstruction (5), enterocolitis (2), or perforation of the colon (2). Eight patients presented after the neonatal period, with constipation. Pathological involvement included rectosigmoid (12), long segment (4), and total colonic aganglionosis (1). Definitive surgery was performed in 14 patients. At the mean follow-up of 8 years (4 to 15 years), only one of the 13 patients has normal bowel function. Eight have persistent soiling, and two have reverted to permanent stomata. There were two deaths in the series; one resulted from enterocolitis complicating HD, and the other from congenital cardiac disease. These data suggest that long-term bowel function in children with HD and trisomy 21 is poor and should be taken into consideration when planning the management.

Child↗
PubMed1994

Selective reduction in intramuscular nerve supporting cells in infantile hypertrophic pyloric stenosis.

Nerve supporting cells were examined immunohistochemically for the expression of S-100 protein and D7 antigen (markers of peripheral Schwann cells) and GFAP (a marker of central-type nerve supporting cells) in pyloric tissue from 18 patients with infantile hypertrophic pyloric stenosis (IHPS) and 10 age-matched controls. In both the IHPS and control groups there was strong staining of the myenteric plexus by all three antibodies. Within the normal pyloric muscle, there was strong staining of nerve fibers by S-100 and D7, but fibers positive for GFAP were considerably less frequent. In the IHPS cases, S-100, D7, and GFAP immunoreactive fibers were either absent or markedly reduced within the hypertrophied circular and longitudinal muscles. Because supporting nerve cells are essential in the maintenance of basic physiological functions of neurons, their absence within the hypertrophied pyloric muscle may be an important factor in the pathogenesis of IHPS.

Biomarkers↗
PubMed1994

Nerve growth factor receptor staining of suction biopsies in the diagnosis of Hirschsprung's disease.

The authors studied rectal suction biopsy material in 60 consecutively treated patients suspected of having Hirschsprung's disease (HD) (age range, 3 days to 12 years). According to acetylcholinesterase (AChE) staining, 10 patients had HD, three had neuronal intestinal dysplasia (NID), and 47 were normal. The diagnoses were confirmed by H&E staining of biopsy material and by examination of surgically resected material in the HD and NID cases. The 60 cases were stained with a monoclonal antibody to the nerve growth factor receptor (NGFR) using immunohistochemistry on fresh frozen biopsy tissue. In the 47 normal biopsy specimens, there was a large number of immunoreactive fibers in the lamina propria, and staining of the muscularis mucosae and submucous ganglia. In contrast, there were no immunoreactive fibers in the lamina propria in patients with HD and NID. A striking finding was the strong expression of immunoreactivity on the perineurium of submucosal hypertrophic nerve trunks in cases of HD. The results indicate that NGFR immunoreactivity is similar in specificity and sensitivity to AChE in the diagnosis of HD. Because the technique uses an immunocytochemical rather than a histochemical technique and the results were easier to interpret, NGFR staining may be an important additional technique to diagnose HD.

Biopsy↗
PubMed1994

Small intestinal atresia: effect on fetal nutrition.

The peak velocity for fetal weight gain occurs in the last few weeks of pregnancy. As the fetus matures, it swallows and absorbs an increasing amount of amniotic fluid, which contributes to the growth of the fetus. The authors studied cases of small intestinal atresia (IA) treated over 9 years to determine whether amniotic fluid has any nutritive role in the development of human fetus, and if it does, at what stage of gestation is the contribution of amniotic fluid significant to fetal nutrition. Fifty-nine newborns had IA (24 jejunal, 35 ileal). Ten of the patients had associated anomalies (3 cystic fibrosis, 2 congenital heart disease, 1 neural tube defect, 1 microcephaly, 2 malrotation, 1 vesicoureteric reflux). Among the 24 babies with jejunal atresia, one was a twin, and birth weight was not recorded for another. These two patients were excluded from the study. Of the remaining 22 patients with jejunal atresia, 10 were born before 36 weeks' gestation; only five of 35 patients with ileal atresia were born before 36 weeks' gestation. Fourteen patients were below the 10th percentile for birth weight after correction for gestational age, one was born before 36 weeks, and 13 were born after 36 weeks. Five (41.7%) of the 12 patients with jejunal atresia who were born after 36 weeks' gestation were underweight, as were eight (26.7%) of the 30 patients with ileal atresia. Thus, it appears that amniotic fluid contributes to the fetal growth in the last few weeks of gestation, and the higher the obstruction in the small intestine, the more pronounced the effect on the nutrition of the fetus.

Amniotic Fluid↗
PubMed1994

Plasma endothelin levels in congenital diaphragmatic hernia.

Persistent pulmonary hypertension (PPH) together with pulmonary hypoplasia accounts for high mortality among patients with congenital diaphragmatic hernia (CDH). Endothelin (ET) is a recently described endothelium-derived vasoconstrictor peptide with a potent and sustained effect. The authors examined plasma ET levels in eight patients with CDH who had respiratory distress at birth and in 15 age-matched controls. The plasma ET levels were measured using a highly sensitive and specific enzyme immunometeric assay (EIA) preoperatively, intraoperatively, and 24 and 48 hours postoperatively. The mean preoperative plasma ET level (53.9 +/- 21.1 pg/mL) of the patients was significantly (P < .01) higher than that of controls (5.9 +/- 4.5 pg/mL). Two patients who died before operation had plasma ET levels of 60 pg/mL and 82 pg/mL, respectively. Three patients who had PPH postoperatively continued to have high ET levels, and at 48 hours, the mean plasma ET level in these patients was 33 pg/mL. In contrast, in the three patients who survived after repair of CDH, the mean plasma ET level at 48 hours was 1.3 pg/mL. The authors further examined the lungs of two patients who died before operation for the expression of ET, using immunocytochemistry. Pulmonary endothelial cells had strong ET staining compared with control tissues. These findings suggest that ET may be a pathophysiological mediator of pulmonary hypertension in patients with CDH.

Endothelins↗
PubMed1994

Particles found in lung and brain following subureteral injection of polytetrafluoroethylene paste are not teflon particles.

We injected 0.3 ml. of polytetrafluoroethylene paste (Polytef) behind the left submucosal ureter in 4 mini-pigs and 4 dogs, and 2 dogs and 2 mini-pigs underwent sham operation and acted as controls. Two mini-pigs were injected with 0.5 ml. polytetrafluoroethylene (Teflon) suspended in 50 ml. of normal saline into a peripheral vein and 2 dogs were injected with 0.5 ml. polytetrafluoroethylene into a bladder vein. In addition, 4 dogs were injected with 0.1 ml. polytetrafluoroethylene paste suspended in 20 ml. saline into the right carotid artery. The lungs and brain from half of the animals who had subureteral and intravascular injection of polytetrafluoroethylene paste as well as sham operated animals were dissolved in sodium hypochlorite solution. The resulting organ suspensions were then centrifuged and the smear preparations of the precipitate were examined by polarized light microscopy, scanning electron microscopy and x-ray microanalysis. Polytetrafluoroethylene paste suspended in saline acted as positive control for polytetrafluoroethylene particles. Lungs and brain from the remaining animals were fixed in formalin solution. The brain and lungs of animals who underwent subureteral injection with a minimal amount of polytetrafluoroethylene paste carefully placed in the submucosal plane showed no evidence of polytetrafluoroethylene on histological examination, polarized light microscopy, scanning electron microscopy and x-ray microanalysis.

Animals↗