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Biomedical subjects

E Cutz

Publications and source records attributed to E Cutz.

At least 55 records · Page 3Linked to original sources

Management of fibrosing pancreatitis in children presenting with obstructive jaundice.

BACKGROUND: Children with fibrosing pancreatitis are conventionally treated surgically to relieve common bile duct (CBD) obstruction caused by pancreatic compression. Residual pancreatic function has not been formally tested in these patients. AIMS: To evaluate the usefulness of non-surgical temporary drainage in children with fibrosing pancreatitis and to assess pancreatic function after resolution of their CBD obstruction. PATIENTS: Four children (1.5-13 years; three girls). METHODS AND RESULTS: Abdominal sonography and computed tomography revealed diffuse enlargement of the pancreas, predominantly the head. The CBD was dilated due to compression by the head of the pancreas. Pancreatic biopsy specimens obtained in three patients showed notable acinar cell atrophy and extensive fibrosis. Cystic fibrosis was excluded. No other cause of pancreatitis was identified. Pancreatic tissue from one patient contained viral DNA sequences for parvovirus B19 detected by polymerase chain reaction; serum IgM to parvovirus was positive. Three patients had temporary drainage of the CBD and one patient underwent a choledochojejunostomy. Serial imaging studies revealed resolution of the CBD obstruction with reduction in pancreatic size. Exocrine pancreatic function deteriorated. Three patients developed pancreatic insufficiency within two to four months of presentation. The fourth patient has notably diminished pancreatic function, but remains pancreatic sufficient. None has diabetes mellitus. CONCLUSIONS: Temporary drainage of the CBD obstruction is recommended in fibrosing pancreatitis in children along with close monitoring of the clinical course, before considering surgery.

Adolescent↗

Calcitonin gene-related peptide expression is altered in pulmonary neuroendocrine cells in developing lungs of rats with congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is associated with high neonatal mortality from lung hypoplasia and persistent pulmonary hypertension. Pulmonary neuroendocrine cells (PNEC) produce calcitonin gene-related peptide (CGRP), a potent vasodilator. We previously reported altered distribution of CGRP-positive PNEC in full-term rats with CDH, that may lead to an imbalance in vasoactive mediators. In the present study we examined the expression of CGRP-positive PNEC during lung development in rats with CDH induced by 2,4-dichlorophenyl-p-nitrophenylether (Nitrofen). Cesarean sections were performed on Days 16, 18, 20, or 22, and the lungs were immunostained for CGRP and immunoreactive cells were quantitated through image analysis. On Day 16, CGRP-immunoreactive staining was negative; on Day 18, CGRP-immunoreactive cells were found in all controls (not exposed to Nitrofen), whereas in CDH pups, CGRP-positive cells were present in only four of six cases. On Day 20, CGRP immunoreactivity was similar in CDH pups, Nitrofen-exposed pups without CDH, and controls. On Day 22 (term), significantly more CGRP-positive cells (i.e., number of positive cells per surface area [mm2] or lung volume [mm3]) were found in ipsilateral lungs of CDH pups than in controls (P < 0.05). The difference was even more striking in contralateral lungs of CDH pups (P < 0.001), ruling out nonspecific effects of Nitrofen. In CDH lungs, the proportion of immunostained epithelium and the size of the neuroendocrine cell clusters (neuroepithelial bodies [NEB]) were not significantly different from those of controls. On Day 22, supraoptimal dilution immunocytochemistry yielded similar results in CDH pups and controls. We conclude that in CDH, CGRP expression in PNEC and NEB is delayed during early stages of lung development. Because CGRP also exhibits growth factor-like properties for endothelium and epithelial cells, the lack of this factor during a crucial developmental stage (canalicular period) may be causally related to lung hypoplasia.

Animals↗

Immunocytochemical localization on O2-sensing protein (NADPH oxidase) in chemoreceptor cells.

A potential candidate for an oxygen-sensing protein in chemoreceptor cells is a heme-linked multicomponent NADPH oxidase, originally described in neutrophils. The postulated function for the oxidase in chemoreceptor cells is to signal changes in oxygen levels (either in the blood or in the airway lumen) via changes in oxygen metabolite production. An alteration in either superoxide (or dismuted hydrogen peroxide) production may affect the gating properties of the O2-sensitive K+ channels. We have previously reported immunohistochemical localization of gp91 glycoprotein component of the oxidase to the plasma membrane of pulmonary neuroepithelial body (NEB) cells. In this study we have investigated the immunocytochemical localization of the other polypeptide components of the oxidase in NEB cells and in the glomus cells of the carotid body. Cultures of dissociated fetal rabbit NEB cells and newborn rat glomus cells were immunostained with specific antibodies recognizing the various polypeptide subunits of the oxidase using indirect immunofluorescence methods. Immunostaining with the anti-oxidase antibodies reveal strong positive reaction in both NEB and glomus cell clusters while other cells were unstained. The positive reaction product was localized to the plasma membrane and/or cytoplasm and no nuclear staining was observed. Live cell labelling studies with anti-p22 antibody showed positive immunofluorescence on the surface of NEB cells, suggesting that this component of the oxidase is also associated with the plasma membrane. In glomus cells, similar strongly positive immunofluorescence signal was observed for p22 and gp91 in paraformaldehyde-fixed cultures, regardless whether they were permeabilized or not. Taken together, our findings of cell surface localization of gp91 and p22 components of the oxidase in chemoreceptive cells suggests that the heme-linked cytochrome b558 component is associated with the plasma membrane. This association allows for direct interaction with the O2-sensitive K+ channel thus forming the molecular complex of membrane bound O2 sensor.

Animals↗

Abdominal calcification in cystic fibrosis with meconium ileus: radiologic-pathologic correlation.

BACKGROUND: There is confusion in the radiological literature as to the site of abdominal calcification in cystic fibrosis (CF) with meconium ileus (MI) in neonates. PURPOSE: To correlate the site of radiographic abdominal calcification with histologic and operative findings. MATERIALS AND METHODS: A review of clinical, radiographic, surgical and histologic data in 58 neonates with CF and MI. RESULTS: Abdominal calcification was identified in 15 (26 %) neonates: on an abdominal radiograph in 8 (13 %), at laparotomy in 3 and histologically in 10 (37 %) of the 27 resected specimens. The radiographic pattern of calcification varied from small specks in three cases to small, better-defined areas in two. In the other three patients, the calcification was more extensive and curvilinear. Histologically, calcification was found to be intramural in ten resected specimens, of which two also had intraluminal and one serosal calcification. The more extensive, curvilinear calcification identified radiographically correlated with histologically proven dystrophic intramural calcification. The less marked flecks or discrete areas of radiographic calcification may represent intramural, serosal or intraluminal calcification. CONCLUSION: Intramural calcification is common microscopically in CF with MI. Extensive radiographic calcification in these patients is more likely to represent intramural rather than serosal or intraluminal calcification.

Calcinosis↗

Is 95% pancreatectomy the procedure of choice for treatment of persistent hyperinsulinemic hypoglycemia of the neonate?

A 95% pancreatectomy became the treatment of choice for persistent hyperinsulinemic hypoglycemia of the neonate (PHHN, Nesidioblastosis) at the author's institution, when lesser resections failed to prevent hypoglycemia in 25% to 50% of cases. With few outcome data available in the literature, the authors reviewed their 25-year experience to assess the efficacy and the long-term consequences of this procedure. Since 1971, 27 infants underwent a 95% pancreatectomy for the treatment of PHHN. None had responded to medical treatment (glucose infusion, glucagon, octreotide, diazoxide), and two had 85% pancreatectomy that failed. The procedure consisted of resecting the pancreas including the uncinate process, leaving only the gland lying between the common bile duct (CBD) and the duodenum and a small rim of pancreas along the duodenal sweep. Hyperinsulinemia and hypoglycemia recurred in nine children (33%), all within 2 to 5 days. Seven of them were subsequently cured with near-total pancreatic resection. Partial pancreatic regrowth was evident at reoperation. In two cases hypoglycemia was controlled with diazoxide and frequent feedings because reoperation was refused. The gross anatomic findings and the histopathology were not predictive of treatment failure. Perioperative complications occurred in four of 27 children (15%) after 95% pancreatectomy and in four of seven children (57%) after near-total pancreatectomy. Clinical follow-up ranged from 0.5 to 18 years (mean, 8 years; median, 8 years). To date, diabetes has developed in 15 children (56%), nine of 20 (45%) after 95% pancreatectomy (mean age, 9.7 years) and six of seven (86%) after a near-total pancreatectomy (mean age, 1.7 years). After 95% pancreatectomy, the incidence of diabetes increased with age, developing in nine of the 13 (69%) children followed up for more than 4 years. The failure of 95% pancreatectomy to prevent hypoglycemia in one third of children with PHHN and the ultimate development of diabetes in a minimum of two-thirds, indicates that an alternative treatment strategy is needed for this disease.

Child, Preschool↗

Peripheral chemoreceptors in congenital central hypoventilation syndrome.

Congenital central hypoventilation syndrome (CCHS) is a rare disorder of unknown etiology, characterized by failure of the autonomic control of respiration. The primary defect is believed to involve central respiratory control; however, no specific lesion has been identified. We report two cases of CCHS (one female, 3 mo of age and one male 2 yr of age) in which there was detailed examination of the neural, muscular, and chemoreceptor components of respiratory control. Although no specific abnormalities were identified in the central nervous system (CNS) or muscles of respiration, striking changes were observed in arterial chemoreceptors, carotid bodies (CB), and airway chemoreceptors, neuroepithelial bodies (NEB). In both cases, CB were small (< 50% of control), with a marked decrease in the number of glomus cells identified by immunostaining for tyrosine hydroxylase and serotonin. Ultrastructural analysis of glomus cells in Case 1 showed a marked decrease in the frequency of dense core vesicles (< 20% of control), the storage site of amine and peptide neurotransmitters. Immunostaining for S100 protein, a marker of sustentacular or Type II cells, was increased up to twofold compared with controls. In the lung, the frequency and size of NEB immunostained for bombesin was increased twofold in both cases, suggesting compensatory hyperplasia of airway chemoreceptors. Since intact peripheral chemoreceptors are essential for respiratory control, especially the response to hypoxia, abnormalities in CB and NEB may contribute to the pathophysiology of CCHS and related conditions such as sudden infant death syndrome (SIDS).

Bombesin↗

Bronchial casts in children: a proposed classification based on nine cases and a review of the literature.

Bronchial casts are characterized by the formation of obstructive airway plugs that may be large enough to fill the branching pattern of an entire lung. The condition is rare but can occur at any age. Casts may be secondary to underlying diseases such as asthma and cystic fibrosis, but there are often no predisposing factors. There is no accepted classification system for bronchial casts; but only a confusion of descriptive terms such as mucoid impaction, fibrinous bronchitis, and pseudomembranous bronchitis. Based on a review of nine well-documented cases and the available literature, we have separated bronchial casts into two well-defined groups: Type 1 (inflammatory), consisting of casts composed mainly of fibrin with a dense eosinophilic inflammatory infiltrate; and Type 2 (acellular), consisting of casts composed mainly of mucin with little or no cellular infiltrate and occurring only in children with congenital cyanotic heart disease. Acute mortality was high in both groups. Survivors of Type 1 casts seem to be well controlled with inhaled steroids. Optimal therapy for patients with Type 2 casts is not clear; the prognosis probably depends on underlying cardiac status. We hope that this simple classification will provide a framework for further study of this obscure condition.

Adolescent↗

Abnormal expression of pulmonary bombesin-like peptide immunostaining cells in infants with congenital diaphragmatic hernia.

Infants with congenital diaphragmatic hernia (CDH) have a high neonatal mortality and morbidity owing to lung hypoplasia and persistent pulmonary hypertension. Pulmonary neuroendocrine cells produce bombesin-like peptide (BLP), a peptide with growth factor-like properties involved in lung development. We examined the expression of BLP immunostaining in pulmonary neuroendocrine cells (PNEC), and in clusters of these cells called neuroepithelial bodies (NEB), in the lungs of three groups of infants: patients with CDH, newborns with lung hypoplasia due to other causes, and control subjects without lung abnormalities. Morphometric analysis included: 1) percent immunostained airways; 2) percent immunostained epithelium (i.e. frequency of PNEC and NEB); and 3) NEB size. Controls and infants with lung hypoplasia did not differ with respect to BLP immunostaining. The ipsilateral and the contralateral lungs in CDH had a similar BLP immunostaining pattern of PNEC and NEB. The BLP immunostaining varied between CDH cases, possibly due to the differences in clinical presentation. The mean NEB size was significantly increased in infants with CDH compared with the other two groups (p = 0.02). Some CDH cases with large NEBs also showed a high percentage of immunostained epithelium. Lung-body weight ratio correlated positively with percent immunostained airways, and negatively with the NEB size. We conclude that in lungs of CDH patients BLP immunostaining in PNEC and NEB differs from that of infants with lung hypoplasia due to other causes and controls. The increased BLP immunostaining observed in some cases of CDH might reflect a compensatory mechanism related to impaired lung development and/or failure of neuropeptide secretion during neonatal adaptation.

Bombesin↗

Hyperplasia of pulmonary neuroendocrine cells in a case of childhood pulmonary emphysema.

Pulmonary emphysema is very uncommon in children in the first decade of life. The few cases documented in the literature were all due to alpha1-antitrypsin deficiency. We present the case of a 6-year-old white boy with chronic cough and dyspnea on exertion. Lung biopsy showed panacinar type emphysema with patent airways and diffuse hyperplasia of pulmonary neuroendocrine cells revealed after immunostaining for bombesin, a peptide produced by these cells. We speculate that idiopathic diffuse hyperplasia of bombesin-producing pulmonary neuroendocrine cells may contribute to the pathogenesis of unusual COPD in childhood.

Bombesin↗

Endogenous hyperinsulinism: diagnosis, management, and long-term follow-up.

Persistent hyperinsulinemic hypoglycemia of the neonate (PHHN) usually presents in the neonate or infant. Although rare, the possibility of PHHN should be considered in all neonates who have unremitting hypoglycemia. Untreated hypoglycemia results in severe neurological disability or death. An inappropriately elevated serum insulin level and low serum ketone and free-fatty-acid concentrations in the presence of hypoglycemia confirm the diagnosis. Early diagnosis and aggressive medical management have reduced the morbidity associated with PHHN. Pancreatic resection is necessary for long-term control of hypoglycemia when medical therapy fails. Ninety-five percent pancreatectomy has been the procedure of choice at the author's institution and other pancreatic centers. However, a review of the authors' experience and of in the English-language literature has demonstrated a 33% failure rate, requiring further surgery or medical management. Furthermore, long-term follow-up showed that diabetes develops in most children who undergo 95% pancreatectomy. The high failure rate of 95% pancreatectomy and the ultimate development of diabetes in virtually all children suggest the alternative approaches should be considered.

Combined Modality Therapy↗

Increase in proliferation and apoptosis of gastric epithelial cells early in the natural history of Helicobacter pylori infection.

Childhood acquisition of Helicobacter pylori is a critical risk factor for gastric cancer. Since tumorigenesis involves deregulation of proliferation and apoptosis, we examined gastric epithelial cell proliferation and apoptosis in H. pylori-infected children. Apoptosis and proliferation of gastric antral epithelial cells in biopsy specimens from patients with H. pylori-induced gastritis, secondary gastritis, and noninflamed controls were compared. p53 protein expression was examined immunohistochemically. Apoptotic cells were identified in the surface epithelium in each group. The apoptotic index was higher in specimens from patients with H. pylori gastritis (120 +/- 10) than secondary gastritis (50 +/- 10) and noninflamed controls (40 +/- 10, analysis of variance P < 0.005). Apoptosis decreased following H. pylori eradication and resolution of gastritis (P < 0.02). An expanded proliferative compartment was identified in H. pylori-induced gastritis (32.4 +/- 3.5; proliferative labeling index +/- SE) compared with secondary gastritis (18.9 +/- 2.8) and noninflamed controls (13.7 +/- 3.1, analysis of variance P < 0.01). The accelerated cell turnover was associated with p53 overexpression (analysis of variance P < 0.005). Accumulation of p53 was not associated with expression of the cyclin-dependent kinase inhibitor p21. The occurrence of altered cell turnover early in the natural history of chronic infection provides an explanation for the increased risk of gastric cancer development associated with childhood acquisition of infection.

Adolescent↗

NADPH-oxidase and a hydrogen peroxide-sensitive K+ channel may function as an oxygen sensor complex in airway chemoreceptors and small cell lung carcinoma cell lines.

Pulmonary neuroepithelial bodies (NEB) are widely distributed throughout the airway mucosa of human and animal lungs. Based on the observation that NEB cells have a candidate oxygen sensor enzyme complex (NADPH oxidase) and an oxygen-sensitive K+ current, it has been suggested that NEB may function as airway chemoreceptors. Here we report that mRNAs for both the hydrogen peroxide sensitive voltage gated potassium channel subunit (KH2O2) KV3.3a and membrane components of NADPH oxidase (gp91phox and p22phox) are coexpressed in the NEB cells of fetal rabbit and neonatal human lungs. Using a microfluorometry and dihydrorhodamine 123 as a probe to assess H2O2 generation, NEB cells exhibited oxidase activity under basal conditions. The oxidase in NEB cells was significantly stimulated by exposure to phorbol esther (0.1 microM) and inhibited by diphenyliodonium (5 microM). Studies using whole-cell voltage clamp showed that the K+ current of cultured fetal rabbit NEB cells exhibited inactivating properties similar to KV3.3a transcripts expressed in Xenopus oocyte model. Exposure of NEB cells to hydrogen peroxide (H2O2, the dismuted by-product of the oxidase) under normoxia resulted in an increase of the outward K+ current indicating that H2O2 could be the transmitter modulating the O2-sensitive K+ channel. Expressed mRNAs or corresponding protein products for the NADPH oxidase membrane cytochrome b as well as mRNA encoding KV3.3a were identified in small cell lung carcinoma cell lines. The studies presented here provide strong evidence for an oxidase-O2 sensitive potassium channel molecular complex operating as an O2 sensor in NEB cells, which function as chemoreceptors in airways and in NEB related tumors. Such a complex may represent an evolutionary conserved biochemical link for a membrane bound O2-signaling mechanism proposed for other cells and life forms.

Animals↗

Congenital cystic adenomatoid malformation of the lung referred as 'airway foreign body'.

Congenital cystic adenomatoid malformation of the lung is an uncommon anomaly. Two patients with this condition were recently referred to the Otolaryngology Service at The Hospital for Sick Children, Toronto, Ontario, for bronchoscopic evaluation of the airway to rule out a foreign body. Although history did not disclose a clear episode of aspiration in either case, chest radiographs showed unilateral lobar hyperinflation with mediastinal shift, consistent with foreign body obstruction. We report two cases to introduce congenital cystic adenomatoid malformation to the English otolaryngology literature and to increase awareness of it among otolaryngologists.

Child, Preschool↗

Acute lung injury after instillation of human breast milk or infant formula into rabbits' lungs.

BACKGROUND: Recent interest in shortening the fasting interval after ingestion of milk products demonstrated large volumes of breast milk in the stomach 2 h after breastfeeding. Although aspiration is a rare event, if it were to occur with human breast milk, it is important to understand the extent of the lung injury that might occur. Therefore, the response to instillation of acidified breast milk and infant formula in the lungs of adult rabbits was studied. METHODS: In 18 anesthetized adult rabbits, 1 of 3 fluids (in a volume of 0.8 ml.kg-1 and pH level of 1.8, acidified with hydrochloric acid); saline, breast milk, or infant formula (SMA, Wyeth, Windsor, Ontario), was instilled into the lungs via a tracheotomy. The lungs were ventilated for 4 h after instillation. Alveolar-to-arterial oxygen gradient and dynamic compliance were measured before and at hourly intervals after instillation. After 4 h, the rabbits were killed and the lungs were excised. Neutrophil infiltration was quantitated by a pathologist blinded to the instilled fluid. A histologic control group of four rabbits was ventilated under study conditions without any intratracheal fluid instillation. RESULTS: Alveolar-to-arterial oxygen gradient increased and dynamic compliance decreased significantly during the 4 h after instillation of both breast milk and infant formula compared with baseline measurements and with saline controls (P < 0.05). The neutrophil counts in the lungs from the saline, breast milk, and formula rabbits were significantly greater than those in the control group. CONCLUSIONS: Instillation of acidified breast milk or infant formula (in a volume of 0.8 ml.kg-1 and pH level of 1.8) into rabbits' lungs induces acute lung injury of similar intensity that lasts at least 4 h.

Acute Disease↗

Expression of gastrin-releasing peptide receptor gene in developing lung.

Bombesin (BN) or its mammalian counterpart, Gastrin-releasing peptide (GRP) is produced by pulmonary neuroendocrine cells (PNEC). The function of GRP as a growth factor involves lung morphogenesis, but the precise mechanism and the target cells have not been defined. We used a nonradioactive in situ hybridization (NISH) and Northern blot analysis for both GRP receptor (GRP-R) and its ligand GRP on samples of fetal and newborn human and rabbit lung. For immunolocalization of BN/GRP and the proliferating lung cell population we used anti-BN/GRP or MIB-1 antibodies, respectively. NISH and Northern blot showed peak expression of GRP-R mRNA on day 24 gestation in the fetal rabbit lung. At the cellular level, GRP-R mRNA was localized mainly in the distal airway epithelial tubes and surrounding mesenchyme, whereas proximal airways showed decreased signal. Epithelium expressing GRP-R showed positive labeling for proliferation antigen in contrast to PNEC, which were negative. In human post-natal lung, strong signal for GRP-R mRNA was localized in the airway epithelial cells and submucosal glands. PNEC in both rabbit and human lung expressed mRNA for GRP, but only in human lung were they immunoreactive for the peptide. However BN/GRP immunoreactive cells were detected in rabbit fetal lung culture. The expression of GRP-R in mammalian lung is developmentally regulated, peaking both spatially and temporally during the phase of rapid airway growth and differentiation. Both epithelial and mesenchymal components express GRP-R consistent with paracrine mechanism for GRP activity during lung morphogenesis.

3T3 Cells↗

Pulmonary neuroendocrine cells in cultures of human infant airway mucosa from postmortem tissues.

Airway mucosa was isolated by enzymatic dissociation from tracheas and bronchi obtained at autopsy from stillbirth, infants, and children. An epithelial cell fraction was recovered that could be cultured on a collagen-coated substratum for at least 7 days. Epithelial cells were identified immunocytochemically with anticytokeratin antibody; pulmonary neuroendocrine cells (PNEC) were identified with antibodies against serotonin, bombesin/GRP, and MOC-1 cell surface antigen. Transmission electron microscopy confirmed neuroendocrine ultrastructural features of PNEC including the presence of neurosecretory dense core vesicles. The ability to recover and maintain viable PNEC in human lung airway epithelial cell cultures from postmortem tissues should facilitate further investigations of PNEC function in normal human lung and in various disease states.

Autopsy↗

Maternal smoking and pulmonary neuroendocrine cells in sudden infant death syndrome.

BACKGROUND: Maternal smoking is a well-recognized risk factor for sudden infant death syndrome (SIDS), but the precise mechanism is unknown. We tested a hypothesis that maternal smoking affects pulmonary neuroendocrine cells (PNECs) and neuroepithelial bodies (NEBs), which are innervated PNEC clusters and presumed airway chemoreceptors. METHODS: Lung sections from infants who died of SIDS and whose mothers smoked during pregnancy (n = 22), infants who died of SIDS and whose mothers were nonsmokers (n = 17), and age-matched control infants (n = 15) who died of other causes were immunostained for bombesin (a PNEC and NEB marker) and assessed morphometrically. RESULTS: The frequency of PNEC (the percentage of airway epithelium immunoreactive for bombesin) was increased up to twofold in the lungs of infants who died of SIDS (7.7 +/- 0.4%) compared with controls (4.9 +/- 0.4%), as was the frequency (40 +/- 3.5 vs 23 +/- 3.7/cm2) and size (748 +/- 46.5 vs 491 +/- 25.8 microns2) of NEBs. In infants who died of SIDS and who were born to smoking mothers, PNEC frequency was increased significantly compared with that in those born to nonsmoking mothers, but the frequency and size of NEBs were not significantly different between the two groups. CONCLUSION: Our findings suggest that maternal smoking potentiates hyperplasia of the PNEC system in the lungs of infants who die of SIDS and that a dysfunction of these cells may contribute to the pathophysiology of SIDS.

Adult↗