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P Puri

Publications and source records attributed to P Puri.

At least 37 records · Page 2Linked to original sources
PubMed2003

Alterations in cholinergic and neuropeptide innervation of urinary bladder following partial bladder outlet obstruction.

Posterior urethral valves (PUV) are the most common cause of bladder outlet obstruction (BOO) in infancy. Bladder instability, poor compliance and myogenic failure are responsible for the poor long-term prognosis in these patients. Previous studies have reported abundance of sensory neuropeptides, e.g. substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and acetylcholinesterase (AchE) nerves in the urinary bladder. We hypothesized that the functional changes in the bladder following BOO are due to alteration in cholinergic and sensory neuropeptide innervation. We therefore investigated cholinergic and sensory innervation of urinary bladder following BOO. Fifteen immature male guinea pigs (Hartley strain) 3-4 weeks old and weighing approximately 250 g. underwent placement of a silk ligature around the bladder neck to induce BOO. Controls included 5 sham-operated animals. The animals were killed 1, 2 and 4 weeks following obstruction, respectively. Whole-mount preparation and conventional sections of bladder wall were performed. AchE histochemistry, and single-label immunofluorescence histochemistry for SP, CGRP and VIP were utilized. Light microscopy and laser scanning confocal microscopy were used to assess the results. AchE staining showed marked increase in cholinergic innervation density within the suburothelial region following BOO. The staining for SP, CGRP and VIP demonstrated marked reduction in sensory nerve density within the suburothelial region 1 week following BOO and the lack of sensory innervation 4 weeks after BOO. The marked reduction in sensory innervation of the bladder and simultaneous increase in cholinergic innervation following BOO may lead to bladder instability and decrease in bladder compliance.

Animals↗
PubMed2003

Alterations in smooth muscle contractile and cytoskeleton proteins and interstitial cells of Cajal in megacystis microcolon intestinal hypoperistalsis syndrome.

BACKGROUND/PURPOSE: Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is characterized by decreased or absent peristalsis. Gastrointestinal motility depends on the enteric nervous system, smooth muscle cells (SMCs), and the interstitial cells of Cajal (ICCs). Contractile and cytoskeleton proteinase are important structural and functional components of SMCs. The aim of study was to examine the expression of contractile and cytoskeleton proteins in SMCs and distribution of ICCs in MMIHS bowel. METHODS: Full-thickness bowel specimens were obtained from 4 infants with MMIHS and 4 controls. Specimens were processed as whole-mount preparations and frozen and paraffin sections. Combined staining of NADPH-d histochemistry/c-kit immunohistochemistry, single and double immunohistochemistry using alpha-smooth muscle actin (alpha-SMA), calponin (CALP), caldesmon (CALD), desmin (DES), protein gene product 9.5 (PGP 9.5) and c-kit antibodies were performed and examined using light and confocal scanning microscopy. RESULTS: alpha-SMA, CALP, CALD, and DES immunoreactivity were reduced markedly in MMIHS bowel compared with controls. Combined NADPH/c-kit staining showed dense network of ICCs around myenteric plexus in MMIHS bowel. In contrast, the intramuscular ICCs either were absent or reduced in MMIHS bowel. CONCLUSIONS: Marked reduction of contractile and cytoskeleton proteins in SMCs combined with reduced expression of intramuscular ICCs in the gut may be responsible for the motility dysfunction in MMIHS.

Case-Control Studies↗
PubMed2003

Effects of benzalkonium chloride treatment on the intramural innervation of the upper urinary tract.

OBJECTIVE: To establish a model for investigating the pathophysiology of pelvi-ureteric junction (PUJ) obstruction, using benzalkonium chloride (BCI) treatment of the upper urinary tract of rabbits, and thus further elucidate the pathophysiology of PUJ obstruction, the most common urinary tract obstruction in children. MATERIALS AND METHODS: Although various histological abnormalities have been described, PUJ obstruction may be functional. Defective innervation in PUJ has been suggested to be a major factor in the failure to transmit peristaltic waves across the PUJ. Previously established animal models of hydronephrosis deal mostly with surgical obstruction of the PUJ, which does not correlate with human congenital hydronephrosis. BCl has been used to ablate selectively neurones of the gastrointestinal myenteric plexus, which generated spastic segments with impaired peristalsis. Thus 12 rabbits were treated with BCl at the PUJ; the right upper urinary tract was dissected extraperitoneally and treated with a local application of 0.1% or 0.5% BCl (six each) for 15 min. The controls were four sham-operated animals treated with saline. The animals were assessed by intravenous urography (IVU) at 4 and 8 weeks after treatment, after which the animals were killed, the upper urinary tracts removed and whole-mounts prepared. Acetylcholinesterase (AChE) histochemistry, and neurofilament and tyrosine hydroxylase (TH) single-enzyme immunohistochemistry were used to detect the intrinsic innervation. RESULTS: None of the animals had hydronephrosis on the IVU or at death. AChE histochemistry, TH and neurofilament immunohistochemistry showed no or very few nerve fibres within the BCl-treated PUJs in both (0.1% and 0.5%) groups. After saline treatment there was normal development of the neuronal plexus within the submucosal, muscular and adventitial layers of the upper urinary tract. CONCLUSION: These results suggest that treatment with BCl is useful for ablating the intrinsic innervation in the upper urinary tract. Defective intrinsic innervation of the upper urinary tract did not lead to clinically or radiologically evident hydronephrosis. Further physiological studies using this model are needed to further elucidate the neuronal and myogenic influence on the development of PUJ obstruction.

Acetylcholine↗
PubMed2003

Notochord anomalies in the adriamycin rat model: A morphologic and molecular basis for the VACTERL association.

BACKGROUND/PURPOSE: The Adriamycin rat model (ARM) is a reliable model of the VACTERL association. The notochord is structurally abnormal in the region of the foregut, midgut, and hindgut in the ARM. The authors hypothesised that notochord anomalies allow ectopic expression of molecular signals in the developing embryo and thus lead to VACTERL malformations. This study was designed to investigate this hypothesis. METHODS: Adriamycin (1.75 mg/kg) was administered intraperitoneally to pregnant rats on days 7, 8, and 9 of gestation. Control animals were given saline. Embryos were recovered on gestational days 10.5 to 14 at (1/2)-day intervals and at full term. The first group of embryos were embedded in resin, and sagittal sections stained with Toluidine blue were studied for morphologic abnormalities. The second group of embryos were examined using in situ hybridization for the expression of Sonic Hedgehog (Shh), a patterning gene implicated in the etiology of the VACTERL association. RESULTS: Twenty-seven of the 28 (96.4%) full-term embryos showed VACTERL anomalies. Forty-five of the 50 (90%) experimental embryos (gestational days 10.5 to 14) showed notochord abnormalities. Abnormal ventral branches from the notochord toward the gut were a commonly observed abnormality. These were seen to impinge on the developing foregut, midgut, dorsal aorta, and kidney. In situ hybridization for Shh showed that these branches from the notochord expressed Shh in 66.6% of experimental embryos. This abnormal Shh expression was not seen in the control embryos. CONCLUSIONS: Adriamycin diffusely induces altered notochord morphology in the rat embryo. The abnormal notochord morphology may allow ectopic expression of Sonic Hedgehog, and, thus, contribute to the malformations found in the VACTERL association.

Abnormalities, Drug-Induced↗
PubMed2003

Mutation analysis of the RET gene in total intestinal aganglionosis by wave DNA fragment analysis system.

BACKGROUND/PURPOSE: Total intestinal aganglionosis (TIA) extending from the duodenum to the rectum is the most rare form of Hirschprung's disease (HSCR) and usually is fatal. RET is the major gene associated with HSCR, and germline mutations of this gene account for up 50% of familial and up to 15 to 20% of sporadic cases in HSCR. The aim of this study was to investigate DNA variants in the RET gene in TIA patients using the WAVE DNA Fragment Analysis System. METHODS: Genomic DNA was extracted from whole blood samples from 6 patients with TIA. Polymerase chain reaction (PCR) amplification of the 21 exons of RET was performed using published oligonucleotide primers. Heteroduplexes were followed by the WAVE DNA Fragment Analysis System with the DNASep cartridge. RESULTS: WAVE system technology detected 16 variants in the RET gene in the 6 patients with TIA. Three patients had a significant mutation in exon 8, 11, and 15, respectively. Thirteen RET polymorphic variants also were detected in the 6 patients, with L746L variant in exon 13 occurring in 4 patients. CONCLUSIONS: WAVE system technology is an efficient method for the detection of DNA sequence variants. Our findings suggest that not only RET mutations but also RET polymorphic variants may contribute to the occurrence of TIA.

Amino Acid Substitution↗
PubMed2003

Pure alcohol injection of a congenital splenic cyst: a valid alternative?

Congenital splenic cysts are a rare entity. They are more frequent in children and young adults. They are true cysts, lined by epithelium with a typical trabeculation. Aspiration and injection with antibiotics (minocycline-tetracycline) or pure alcohol has been reported sparsely with variable results. The purpose of this case study is to report our experience with ultrasound (US)-guided aspiration and injection of a congenital splenic cyst, which, in our case, did not prove a viable alternative to surgical defenestration.

Abdominal Pain↗
PubMed2003

Renal parenchymal damage in sibling vesicoureteric reflux.

AIM: To compare the incidence of renal damage in siblings of patients with vesicoureteric reflux (VUR) who presented with a documented history of urinary tract infection (UTI) with asymptomatic siblings who were diagnosed with reflux during a screening programme for hereditary VUR. METHODS: Medical and radiological records of the VUR patients (1990-2000) were examined for age, gender, mode of presentation, reflux grade and renal damage. RESULTS: VUR was noted in 226 siblings (352 ureters) in 107 families. Of the 119 siblings of index patients, 64 were investigated for a documented UTI and 55 with no history of UTI were detected during screening for sibling reflux. Dimercaptosuccinic acid scan revealed reflux nephropathy in 25 (26%) of the 97 renal refluxing units (RRU) of siblings who presented with a UTI and in 6 (7%) of the 89 RRU of asymptomatic siblings who underwent screening voiding cystourethrography (p=0.0006). Mild renal damage was present in 20 (21%) RRU of siblings with UTI and in 2 (2%) RRU of the screened siblings (p < 0.001). Moderate to severe renal damage was present in 5 (5%) RRU of siblings with UTI and in 4 (4%) RRU of the screened siblings (p > 0.05). CONCLUSION: This study demonstrated that the incidence of mild renal scarring was much higher in siblings who presented with UTI than in asymptomatic siblings. However, the incidence of moderate and severe renal scarring among asymptomatic siblings was comparable to that in siblings with VUR and UTI.

Adolescent↗
PubMed2003

Organized vitreous hemorrhage masquerading as an optic disc melanocytoma.

PURPOSE: To present a case of organized vitreous hemorrhage masquerading an optic disc melanocytoma. DISCUSSION: Optic nerve head melanocytoma is a benign slightly pigmented lesion arising from the edge of the disc presenting with a filed defect. Pigmented nature of the lesion in question due to presence of haemosidrin laden macrophages led a diagnostic dilemma. Trans vitreal biopsy confirmed the diagnosis. CONCLUSIONS: Althought classical in presentation organized blood clots can masquerade a number of lesions including a melanocytoma as in the present scenario.

Adult↗
PubMed2002

Cell death in the early adriamycin rat model.

The adriamycin rat model (ARM) exhibits many features of the VACTERL association. Adriamycin is a cytotoxic drug used in cancer chemotherapy. Although its exact mode of action is not clear, it is presumed to have a similar cytotoxic role in the developing embryo. Lysotracker red (LT) is a dye that stains phagolysosomes and apoptotic bodies and allows entire rodent embryos to be stained for apoptosis. We hypothesised that there was increased cell death in adriamycin-exposed embryos. To investigate this hypothesis, adriamycin (1.75 mg/kg) was given intraperitoneally to rats on days 7, 8, and 9 of pregnancy. A control group was given saline on the same schedule. Embryos were recovered at 3, 12, 24, and 48 h following the last dose and also at term (21 days) to confirm that the usual incidence of congenital anomalies found in the ARM was obtained in our animal model. Embryos were embedded in resin, sectioned, and studied by light microscopy. Embryos from the 3-h and 24-h groups were studied using LT and confocal microscopy to search for evidence of apoptosis. All term newborns (100%) from the adriamycin-treated group demonstrated the typical abnormalities found in the ARM, i.e., oesophageal atresia, multiple gastrointestinal atresias, vertebral malformations, absent tails, ureterohydronephrosis, etc. In the 9.5-day adriamycin group there was no difference in appearance between the experimental and control embryos. Specifically, no cellular debris or increased cell turnover indicative of adriamycin cytotoxicity was observed in the experimental group. At day 10.5, 90% of embryos from two separate litters had evidence of notochordal distortion and tethering to the gut or gut-tube abnormalities. These findings were not observed in the control embryos. Confocal microscopy and LT examination of the embryos from litters killed at 3 and 24 h following the last dose of adriamycin demonstrated no evidence of increased cell death in adriamycin-exposed embryos compared to control embryos. The absence of significant apoptosis in the developing embryos in the immediate period following administration of adriamycin suggests that the teratogenic effect of adriamycin is not caused by cell death.

Abnormalities, Drug-Induced↗
PubMed2002

Cervical thymic cysts.

Thymic cysts are considered uncommon lesions in the differential diagnosis of pediatric neck masses. They usually present in the 1st decade after the age of 2 years, possibly because the thymus attains its greatest development before puberty. They may be found anywhere along the normal descent route of the thymus gland from the mandible to the sternal notch; 50% extend into the mediastinum. Most patients are asymptomatic, although respiratory complications may occur. A review of the operative records in our hospital over the last 10 years revealed two cases of cervical thymic cysts (CTC) in a 5- and a 9-year-old boy. Both children presented with an atraumatic, painless, enlarging mass in the left side of the neck anterior to the sternocleidomastoid muscle. Neither boy had respiratory problems or swallowing difficulties. Ultrasound and computed tomography showed a lesion consistent with a tentative diagnosis of a branchial cyst in one boy and an extensive cystic hygroma in the other. Both lesions were approached through a transverse cervical incision and, although closely adherent to the internal jugular vein, carotid artery, and vagus nerve, were resected completely. There were no postoperative complications and so far there has been no recurrence. CTCs are uncommon benign lesions that should be considered in the evaluation of neck masses in children. Preoperative diagnosis is unusual and, at this time, there is no preoperative radiologic test that can accurately identify a neck mass as a CTC. Histologic investigation of the excised specimen showing thymic tissue remnants with pathognomonic Hassall's corpuscles and cholesterol clefts in the cyst wall is the only definitive diagnosis. Evolution is benign. Intact, complete surgical excision remains the treatment of choice.

Child↗
PubMed2002

Autoamputation of a congenital oropharyngeal hairy polyp.

Hairy polyps or dermoids are rare, benign congenital tumours of the oronasopharynx containing elements of both ectodermal and mesodermal origin. They occur most commonly in young infants and can cause respiratory distress or failure to thrive due to feeding difficulties. Computed tomography, magnetic resonance imaging, and barium video fluoroscopy can be useful in delineating the origin and extent of these lesions. Treatment usually consists of surgical removal. We describe a case of spontaneous resolution of symptoms in an 11-week-old baby due to autoamputation of the lesion.

Dermoid Cyst↗
PubMed2002

Increased vascular endothelial growth factor peptide and gene expression in hypoplastic lung in nitrofen induced congenital diaphragmatic hernia in rats.

Persistent pulmonary hypertension (PPH) in congenital diaphragmatic hernia (CDH) lung has been shown to be associated with structural changes in the pulmonary vasculature, including medial and adventitial thickening. Vascular endothelial growth factor (VEGF) is a potent mitogenic and permeability factor targeting predominantly endothelial cells. mRNA encoding VEGF is detected in all fetal tissues and is most abundant in fetal lung, kidney, and liver. Recently, antenatal dexamethasone (Dex) treatment has been shown to prevent pulmonary-artery structural changes in experimentally-produced CDH. The aim of this study was to investigate mRNA and protein levels of VEGF in CDH lung and to determine whether antenatal Dex treatment has any effect on the production of VEGF. A CDH model was induced in pregnant rats following administration of 100 mg nitrofen on days 9.5 of gestation (term=22 days). Dex 0.25 mg/kg was given on day 18.5 and 19.5. Cesarean section was performed on day 21 of gestation. The fetuses were divided into three groups: normal controls (NC, n=8); nitrofen-induced CDH (CDH, n=8); and nitrofen-induced CDH with antenatal Dex treatment (CDH-Dex, n=8). Protein and mRNA were extracted from the whole lung. VEGF protein was measured by ELISA assay and mRNA expression was evaluated by reverse transcription-polymerase chain reaction. Immunohistochemistry using anti-rat VEGF antibody was also performed in each group. VEGF protein as well as mRNA expression were significantly increased in the CDH group compared to the NC group, which was not affected by antenatal Dex treatment. VEGF immunoreactivity in pulmonary vessel walls was increased in the CDH and CDH-Dex groups compared to the NC group. The enhanced VEGF protein and mRNA expression in CDH lung suggests that increased local synthesis of VEGF may be responsible for the structural changes in the pulmonary vasculature in CDH lung. VEGF expression in CDH lung is not downregulated by antenatal Dex treatment.

Analysis of Variance↗
PubMed2002

Treatment of vesicoureteric reflux by endoscopic injection of Teflon. 1984.

Thirteen girls with grade III-V vesicoureteric reflux were treated by endoscopic injection of Teflon paste behind the intravesical ureter. Fourteen of the 18 treated ureters showed complete absence of reflux after one injection of Teflon. Three ureters required a second injection of Teflon for successful treatment of the reflux. One ureter with grade IV reflux was converted to grade II reflux. Properly carried out, this procedure corrects reflux. It takes less than 15 minutes, may be done as a day procedure, and avoids open surgery. There have been no complications. (Reprinted with permission from Br Med J, 289: 7-9, 1984)

Child↗
PubMed2002

Long-term outcome of the retained ureteral stump after lower pole heminephrectomy in duplex kidneys.

OBJECTIVES: Duplication of the ureter and renal pelvis is the most common upper urinary tract anomaly in childhood. The anatomical and functional divisions between upper and lower moieties of duplex kidney are extremely variable. The underlying pathological condition associated with a lower moiety is usually massive vesicoureteral reflux (VUR) to the lower collecting system and only rare obstruction. The non-functioning upper moiety is usually associated with obstructive ectopic ureter (with or without ureterocele). Most lower pole heminephrectomies are carried out for non-functioning lower moieties. In most cases, the lower defunctionalised segment of the ureter is left in situ. Complete ureterectomy is usually performed if presence of VUR into the lower end of the corresponding ureter is shown. There is little information on the long-term outcome of residual ureteral 'stumps'. The purpose of our study was to review the long-term outcome of retained ureteral stumps in children undergoing heminephrectomy for non-functioning lower pole moieties in duplex kidneys. MATERIALS AND METHODS: The medical records of 19 patients who underwent 20 lower pole heminephrectomies for a non-functioning lower pole moiety of a duplex kidney between January 1990 and December 2000 were reviewed retrospectively. Median age at heminephrectomy was 4.5 years (range: 1 month to 12 years). Indications for heminephrectomy in the 20 renal units was reflux nephropathy in 16 (80%) and obstructive nephropathy in 4 (20%). All corresponding ureters were taken down as low as possible and transfixed through the heminephrectomy incision. Median follow-up was 8.5 years (range: 1-11 years). RESULTS: Eight (40%) showed VUR into the stump after lower pole heminephrectomy. Two of these underwent subureteral endoscopic correction of VUR with polytetrafluoroethylene paste and resection of the stump was carried out in remaining two patients for recurrent urinary tract infections (UTI). Remaining four of the eight patients demonstrated spontaneous resolution of VUR during follow-up. CONCLUSIONS: Our data suggest that the vast majority of patients with residual ureteral stumps after lower pole heminephrectomy do not require stump resection at long-term follow-up.

Child↗