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Biomedical subjects

J M Wilson

Publications and source records attributed to J M Wilson.

At least 145 records · Page 8Linked to original sources

Correction of ureagenesis after gene transfer in an animal model and after liver transplantation in humans with ornithine transcarbamylase deficiency.

We report effects of gene transfer and liver transplantation on urea synthesis in ornithine transcarbamylase deficiency (OTCD). We measured the formation of [15N] urea after oral administration of 15NH4Cl in two girls with partial OTCD before and after liver transplantation. Ureagenesis was less than 20% of that observed in controls before transplantation, and was normalized afterward. Studies performed on the OTCD sparse fur (spf/Y) mouse showed discordance between OTC enzyme activity and ureagenesis with modest increases in OTC enzyme activity after gene transfer resulting in significant improvement in ureagenesis. This study suggests that both liver transplantation and gene therapy may be effective in improving ureagenesis in OTCD.

Animals↗

Reversible congestive heart failure caused by myocardial hibernation.

Myocardial hibernation is reversible contractile dysfunction of cardiac myocytes caused by chronic ischemia. Animal studies and observations in human beings suggest that the term hibernation is a misnomer. Repetitive ischemic insult that does not produce necrosis results in functional and histologic tissue deterioration, which culminates in myocyte apoptosis. Revascularization of "hibernating" myocardium results in partial or complete recovery of function, depending upon the duration of ischemia and the severity of cellular degeneration. Improvement in global left ventricular function is proportional to the quantity of hibernating tissue that is revascularized, but this threshold quantity has not been determined with certainty. Diagnostic methods used to detect viable tissue within akinetic left ventricular segments depend upon the recognition of recruitable contractile function or the active concentration of a radioactive tracer. No diagnostic method has shown clear superiority. The most sensitive methods appear to be single-photon emission computed tomographic imaging after reinjection of thallium-201 at 24 hours and positron-emission tomographic imaging with 18F-fluorodeoxyglucose. The most specific diagnostic method appears to be measurement of dobutamine-stimulated contractile function, using either echocardiography or gated magnetic resonance imaging. We present a review of the pathophysiology, diagnosis, and treatment of myocardial hibernation, and include an illustrative case report involving a 57-year-old man with myocardial hibernation.

Angioplasty, Balloon, Coronary↗

Efficient mitochondrial import of newly synthesized ornithine transcarbamylase (OTC) and correction of secondary metabolic alterations in spf(ash) mice following gene therapy of OTC deficiency.

BACKGROUND: The mouse strain sparse fur with abnormal skin and hair (spf(ash)) is a model for the human ornithine transcarbamylase (OTC) deficiency, an X-linked inherited urea cycle disorder. The spf(ash) mouse carries a single base-pair mutation in the OTC gene that leads to the production of OTC enzyme at 10% of the normal level. MATERIALS AND METHODS: Recombinant adenoviruses carrying either mouse (Ad.mOTC) or human (Ad.hOTC) OTC cDNA were injected intravenously into the spf(ash) mice. Expression of OTC enzyme precursor and its translocation to mitochondria in the vector-transduced hepatocytes were analyzed on an ultrastructural level. Liver OTC activity and mitochondrial OTC concentration were significantly increased (300% of normal) in mice treated with Ad.mOTC and were moderately increased in mice receiving Ad.hOTC (34% of normal). The concentration and subcellular location of OTC and associated enzymes were studied by electron microscope immunolocalization and quantitative morphometry. RESULTS: Cytosolic OTC concentration remained unchanged in Ad.mOTC-injected mice but was significantly increased in mice receiving Ad.hOTC, suggesting a block of mitochondria translocation for the human OTC precursor. Mitochondrial ATPase subunit c [ATPase(c)] was significantly reduced and mitochondrial carbamy delta phosphate synthetase I (CPSI) was significantly elevated in spf(ash) mice relative to C3H. In Ad.mOTC-treated mice, the hepatic mitochondrial concentration of ATPase(c) was completely normalized and the CPSI concentration was partially corrected. CONCLUSIONS: Taken together, we conclude that newly synthesized mouse OTC enzyme was efficiently imported into mitochondria following vector-mediated gene delivery in spf(ash) mice, correcting secondary metabolic alterations.

Adenoviridae↗

Interferon-beta gene therapy inhibits tumor formation and causes regression of established tumors in immune-deficient mice.

Despite the potential of type 1 interferons (IFNs) for the treatment of cancer, clinical experience with IFN protein therapy of solid tumors has been disappointing. IFN-beta has potent antiproliferative activity against most human tumor cells in vitro in addition to its known immunomodulatory activities. The antiproliferative effect, however, relies on IFN-beta concentrations that cannot be achieved by parenteral protein administration because of rapid protein clearance and systemic toxicities. We demonstrate here that ex vivo IFN-beta gene transduction by a replication-defective adenovirus in as few as 1% of implanted cells blocked tumor formation. Direct in vivo IFN-beta gene delivery into established tumors generated high local concentrations of IFN-beta, inhibited tumor growth, and in many cases caused complete tumor regression. Because the mice were immune-deficient, it is likely that the anti-tumor effect was primarily through direct inhibition of tumor cell proliferation and survival. Based on these studies, we argue that local IFN-beta gene therapy with replication-defective adenoviral vectors might be an effective treatment for some solid tumors.

Adenoviridae↗

High-titer adeno-associated viral vectors from a Rep/Cap cell line and hybrid shuttle virus.

Adeno-associated virus (AAV) is a potential vector for in vivo gene therapy. A critical analysis of its utility has been hampered by methods of production that are inefficient, difficult to scale up, and that often generate substantial quantities of replication-competent AAV. We describe a novel method for producing AAV that addresses these problems. A cell line, called B50, was created by stably transfecting into HeLa cells a rep/cap-containing plasmid utilizing endogenous AAV promoters. Production of AAV occurs in a two-step process. B50 is infected with an adenovirus defective in E2b, to induce Rep and Cap expression and provide helper functions, followed by a hybrid virus in which the AAV vector is cloned in the E1 region of a replication-defective adenovirus. This results in a 100-fold amplification and rescue of the AAV genome, leading to a high yield of recombinant AAV that is free of replication-competent AAV. Intramuscular injection of vector encoding erythropoietin into skeletal muscle of mice resulted in supraphysiologic levels of hormone in serum that was sustained and caused polycythemia. This method of AAV production should be useful in scaling up for studies in large animals, including humans.

Animals↗

Impact of preexisting and induced humoral and cellular immune responses in an adenovirus-based gene therapy phase I clinical trial for localized mesothelioma.

Little is known about the immune responses induced by recombinant adenoviral (Ad) vectors in humans. The humoral and cellular immune responses were therefore analyzed in 21 patients with localized malignancy (mesothelioma), who received intrapleurally high doses of a replication-defective Ad5 vector carrying a suicide gene. Eight of 21 patients had pretreatment titers of neutralizing antibodies (NAb) to Ad at > or =1:100. Peripheral blood mononuclear cells (PBMCs) proliferated in response to adenoviral 5 structural proteins before treatment in 17 of 21 patients. Preexisting humoral and cellular immunity did not preclude gene transfer. Vector instillation induced high titers of nonneutralizing and neutralizing anti-Ad antibody (4- to 341-fold increase in 18 of 20 patients) in a dose-dependent manner. Three patients generated antibodies to the transgene, herpes simplex virus thymidine kinase. Ad5-specific proliferation of PBMCs increased significantly (>3-fold) after vector administration in 12 of 21 patients in a dose-dependent manner. Thus, replication-defective Ad5 administered intrapleurally induced significant humoral and cellular immune responses that induced no obvious adverse clinical sequelae.

Adenoviridae↗

Evaluating the potential of germ line transmission after intravenous administration of recombinant adenovirus in the C3H mouse.

The goal of this study is to assess the likelihood that an adenoviral vector disseminated to gonads will be transmitted to offspring. This study is based on the observation that systemically administered vector can be detected in both ovaries and testes, using sensitive nested PCR techniques. Although the extent of vector dissemination to gonads is extremely small, as it is detectable only by nested PCR, it is unclear where it is located within these tissues and whether the DNA is capable of integration and transmission to offspring. A protocol was developed in C3H mice to address this question. Both male and female C3H mice were injected with a high dose of H5.001CBhOTC, an E1- and E4-deleted vector expressing human ornithine transcarbamylase. This dose of vector was sufficient to target 80% of hepatocytes (Gao et al., J. Virol. 1996; 70:8934-8943) and disseminate, at low levels, to both ovaries and testes in 94% of animals as determined by PCR. Vector-administered animals and controls were mated and 814 offspring were evaluated for germ line transmission of the adenoviral vector by DNA hybridization of total cellular DNA extracted from the fetus. Southern blot analysis showed no evidence of germ line transmission in 578 offspring of crosses in which either one or both parents received recombinant adenovirus.

Adenoviridae↗

Human beta-defensin 2 is a salt-sensitive peptide antibiotic expressed in human lung.

Previous studies have implicated the novel peptide antibiotic human beta-defensin 1 (hBD-1) in the pathogenesis of cystic fibrosis. We describe in this report the isolation and characterization of the second member of this defensin family, human beta-defensin 2 (hBD-2). A cDNA for hBD-2 was identified by homology to hBD-1. hBD-2 is expressed diffusely throughout epithelia of many organs, including the lung, where it is found in the surface epithelia and serous cells of the submucosal glands. A specific antibody made of recombinant peptide detected hBD-2 in airway surface fluid of human lung. The fully processed peptide has broad antibacterial activity against many organisms, which is salt sensitive and synergistic with lysozyme and lactoferrin. These data suggest the existence of a family of beta-defensin molecules on mucosal surfaces that in the aggregate contributes to normal host defense.

Amino Acid Sequence↗

The peptide antibiotic LL-37/hCAP-18 is expressed in epithelia of the human lung where it has broad antimicrobial activity at the airway surface.

The airway surface is an important host defense against pulmonary infection. Secretion of proteins with antimicrobial activity from epithelial cells onto the airway surface represents an important component of this innate immune system. Defensins are the best characterized epithelial-derived peptide antibiotics. A member of another family of peptide antibiotics called cathelicidins recently was identified from human bone marrow. We show in this paper that this human peptide named LL-37/hCAP-18 also may play a role in innate immunity of the human lung. In situ hybridization localized high levels of LL-37/hCAP-18 RNA to surface epithelial cells of the conducting airway as well as serous and mucous cells of the submucosal glands. LL-37/hCAP-18 peptide with antimicrobial activity was partially purified from airway surface fluid from human lung and a human bronchial xenograft model. The synthetic peptide LL-37 demonstrated antibiotic activity against a number of Gram-negative and Gram-positive organisms including Pseudomonas aeruginosa; bacterial killing of LL-37 was sensitive to NaCl and was synergistic with lactoferrin and lysozyme. In summary, we show that LL-37/hCAP-18 is a peptide with broad antimicrobial activity that is secreted onto the airway surface from epithelial cells of the human lung.

Anti-Bacterial Agents↗

Dopamine D2 and D4 receptor ligands: relation to antipsychotic action.

Since the discovery that the antipsychotic action of phenothiazines was mediated by dopamine D2 receptors, the dopamine system has been scrutinized for schizophrenia related abnormalities. The focus has been to create neuroleptics with improved antipsychotic profiles and reduced side effects. With the identification of multiple dopamine receptor subtypes, the hypotheses regarding the role of dopamine in schizophrenia and antipsychotic action of neuroleptics have been refined. Even after the molecular identification of newer dopamine D2-like receptor subtypes (D3 and D4), the dopamine D2 receptor is still considered the predominant site for antipsychotic action. However, there has been much debate concerning the modulatory role of other dopamine receptor sites in the mechanism of action of antipsychotic drugs. Specifically, the dopamine D4 receptor has received much attention in this regard, since the atypical antipsychotic agent, clozapine, preferentially blocks this receptor subtype as compared with dopamine D2 and D3 receptors. In this review we will highlight some of the observations and arguments regarding the involvement of the dopamine D2 and D4 receptor sites in the therapeutic efficacy of antipsychotic medication.

Animals↗

Adenovirus-mediated herpes simplex virus thymidine kinase/ganciclovir gene therapy in patients with localized malignancy: results of a phase I clinical trial in malignant mesothelioma.

Malignant pleural mesothelioma is a fatal neoplasm that is unresponsive to standard modalities of cancer therapy. We conducted a phase I dose-escalation clinical trial of adenoviral (Ad)-mediated intrapleural herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) gene therapy in patients with mesothelioma as a model for treatment of a localized malignancy. The goals of this phase I trial were to assess the safety, toxicity, and maximally tolerated dose of intrapleural Ad.HSVtk, to examine patient inflammatory response to the viral vector, and to evaluate the efficiency of intratumoral gene transfer. Twenty-one previously untreated patients were enrolled in this single-arm, dose-escalation study with viral doses ranging from 1 x 10(9) plaque-forming units (pfu) to 1 x 10(12) pfu. A replication-incompetent recombinant adenoviral vector containing the HSVtk gene under control of the Rous sarcoma virus (RSV) promoter-enhancer was introduced into the pleural cavity of patients with malignant mesothelioma followed by 2 weeks of systemic therapy with GCV at a dose of 5 mg/kg twice a day. The initial 15 patients underwent thoracoscopic pleural biopsy prior to, and 3 days after, vector delivery. The last six patients underwent only the post-vector instillation biopsy. Dose-limiting toxicity was not reached. Side effects were minimal and included fever, anemia, transient liver enzyme elevations, and bullous skin eruptions, as well as a temporary systemic inflammatory response in those receiving the highest dose. Strong intrapleural and intratumoral immune responses were generated. Using RNA PCR, in situ hybridization, immunohistochemistry, and immunoblotting, HSVtk gene transfer was documented in 11 of 20 evaluable patients in a dose-related fashion. This study demonstrates that intrapleural administration of an adenoviral vector containing the HSVtk gene is well tolerated and results in detectable gene transfer when delivered at high doses. Further development of therapeutic trials for treatment of localized malignancy using this vector is thus warranted.

Adenoviruses, Human↗

Selective gene transfer into the liver of non-human primates with E1-deleted, E2A-defective, or E1-E4 deleted recombinant adenoviruses.

Preclinical studies were designed to investigate the feasibility and safety of recombinant adenoviruses transduced into the hepatic artery of nonhuman primates. The vectors used are recombinant adenoviruses deleted in E1 and contain either a temperature-sensitive mutation in the E2a gene, which encodes a defective DNA-binding protein at nonpermissive temperatures, or a deletion of the E4 region, including open reading frame (ORF) 6. Six 8- to 10-kg baboons underwent femoral artery cannulation, and angiographic techniques were used to introduce vector selectively into either a portion of the right lobe of the liver via a branch of the right hepatic artery or the common hepatic artery. Necropsies were performed at 4, 29, or 61 days. Serial sequential liver biopsies were performed in the baboons that survived 29 or 61 days. In the 2 baboons with vector transduction into the right hepatic artery, X-Gal histochemical analysis of the liver showed evidence of quantitatively increased gene transfer in the targeted lobe; however, gene transfer was present throughout the liver. Quantitative analysis of histopathology showed that portal inflammation was present throughout both livers transduced with the highest dose of vector. No differences were seen in the level of portal inflammation in targeted and untargeted lobes despite the observed qualitative and quantitative differences in gene expression. Southern blot analysis of total cellular DNA isolated from targeted and nontargeted lobes showed similar levels of viral DNA throughout the liver. Polymerase chain reaction (PCR) analysis was able to detect viral DNA sequence in gonads and brain as well as many other tissues in baboons treated with high-dose vector. In baboons treated with lower doses of an E1-E4 deleted vector expressing the human ornithine transcarbamylase (OTC) gene, DNA was detectable by nested PCR in liver but not gonads at days 29 and 61. The data suggest that intraarterial administration of recombinant adenoviral E1-E4 deleted vector is feasible and safe. At high doses of vector, widespread dissemination of vector DNA is seen. At low doses, hepatic gene transfer is not associated with vector DNA dissemination to gonads.

Adenoviridae↗

Biosynthesis of endotubin: an apical early endosomal glycoprotein from developing rat intestinal epithelial cells.

Endosomes are the site of sorting of internalized receptors and ligands in all cell types and, in polarized cells, the apical endosomal compartment is involved in the selective transepithelial transport of immunoglobulins and growth factors. The biochemical composition of this specialized compartment remains largely unresolved. We have characterized a glycoprotein, called endotubin, that is located in the apical endosomal tubules of developing rat intestinal epithelial cells. A monoclonal antibody against endotubin recognizes a broad band of 55-60kDa, which upon isoelectric focusing can be resolved into two bands, and a faint band of 140kDa. Metabolic labelling followed by immunoprecipitation indicates that endotubin is synthesized as a 140kDa precursor that is cleaved to the 55-60kDa forms. High pH washing of endosomal membranes removes the 55-60kDa forms from the membrane, whereas the high-molecular-mass form remains membrane associated and appears to be an integral membrane protein. Immunoblotting with a polyclonal antibody against the putative cytoplasmic tail of the protein identifies a 140kDa band and a band of 74kDa, presumably the cleavage product. Immunoprecipitation with antibodies against the 55-60kDa form results in coprecipitation of a 74kDa protein, and immunoprecipitation with antibody against the 74kDa protein results in coprecipitation of the 55-60kDa form. Epitope mapping of the monoclonal antibody binding site supports a proposed type I membrane protein orientation. We propose that endotubin is proteolytically processed into a heterodimer with the 55-60kDa fragment remaining membrane-associated through a non-covalent association with the membrane-bound 74kDa portion of the molecule.

Animals↗

Lung deposition of budesonide from turbuhaler in asthmatic children.

UNLABELLED: The aim of our study was to evaluate the effect of age on lung deposition of radiolabelled budesonide, delivered as a dry powder via Turbuhaler to asthmatic children. A group of 23 asthmatic children, aged 6 to 16 years, with relatively stable asthma inhaled 99mTc-labelled budesonide from a dry powder inhaler (Turbuhaler). Body and lung deposition was assessed using a gamma camera. The mean (range) median peak inspiratory flow during inhalation was 65 1 x min(-1) (45 to 76 1 x min(-1)). Mean (range) total lung deposition of 99mTc-labelled budesonide, expressed as a percentage of the metered dose, was 29.1% (15.6-47.2%) and was positively and significantly correlated with age, height and peak inspiratory flow. CONCLUSION: Total lung deposition of radiolabelled budesonide from a dry powder inhaler (Turbuhaler), is age dependent in children with moderate asthma. However, lung deposition is still satisfactory, even in younger children with lower peak inspiratory flows.

Adolescent↗

Fundamentals of coagulation and glycoprotein IIb/IIIa receptor inhibition.

An understanding of the coagulation process and the role of platelets is essential to recognizing the shortcomings of older anticoagulant therapies and appreciating the clinical potential of newer forms of antiplatelet and anticoagulant therapy for acute coronary syndromes. The anticoagulant actions of heparin are severely limited by dependence on antithrombin III, neutralization by platelet factor 4, and the resistance of clot-bound thrombin and platelet membrane-bound factor Xa to the heparin-antithrombin III complex. Unlike heparin, the direct thrombin inhibitors (such as hirudin) are active against both circulating and clot-bound thrombin. However, in recent clinical trials they have not resulted in major improvements in patient outcome. Another new class of drugs, the glycoprotein IIb/IIIa receptor antagonists, blocks the final common pathway of platelet aggregation and is capable of preventing platelet accumulation at sites of injury. The net effect is a dramatic reduction in the amount of platelet membrane available to support the process of coagulation. Clinical trials with the glycoprotein IIb/IIIa inhibitors have suggested that this class of agents may be particularly effective in reducing the thrombotic complications associated with coronary interventional procedures and may be useful in the treatment of acute coronary syndromes.

Acute Disease↗

Flow-function relations during graded coronary occlusions in the dog: effects of transmural location and segment orientation.

OBJECTIVE: The sensitive relationship between regional myocardial perfusion and local systolic deformation during acute myocardial ischemia is not independent of the transmural location or segment orientation. The aim of this study was to determine the effects of fiber orientation and transmural location on the relationships between regional myocardial flow and three-dimensional systolic wall strain during graded coronary artery occlusions. METHODS: Transmural distributions of three-dimensional strain (by biplane radiography of implanted radiopaque markers) and myocardial blood flows (using fluorescent microspheres) were measured in the ischemic region during graded left anterior descending (LAD) coronary artery occlusions in 12 anesthetized dogs. RESULTS: Occlusion of the coronary artery did not significantly alter mean heart rate or end-systolic pressure. As flow decreased during graded occlusions, ischemia significantly changed systolic circumferential, longitudinal, radial, fiber and cross-fiber strains (p < 0.004). There was a significant effect of transmural position on circumferential, cross-fiber and radial strains, but not on fiber or longitudinal strains. Ischemia significantly altered all normal strains: circumferential, longitudinal, fiber, cross-fiber and radial. There was a strong interaction effect between transmural location and blood flow for circumferential, cross-fiber and radial strains, but not fiber or longitudinal strains. CONCLUSION: During non-transmural ischemia, there is evidence of strong transmural tethering in the cross-fiber direction, whereas the fiber-strain flow relation is independent of transmural position. Thus, whether the relationship between local myocardial bloodflow and systolic strain during acute ischemia is dependent on transmural location, depends on segment orientation.

Animals↗

Continuous intrapulmonary distension with perfluorocarbon accelerates neonatal (but not adult) lung growth.

BACKGROUND/PURPOSE: We have previously demonstrated that experimental fetal tracheal ligation reverses the structural and physiological effects of pulmonary hypoplasia associated with congenital diaphragmatic hernia. The purpose of this study was to determine if lung growth could be similarly accelerated postnatally by continuous liquid-based intrapulmonary distension. METHODS: Ten neonatal lambs were divided into two experimental groups. Five neonatal animals underwent a right thoracotomy with isolation of the anterior superior segment of the right upper lobe. A pressure monitoring catheter was introduced and perfluorocarbon (PFC) was instilled into the segment. Animals were subjected to a 21-day distention period with continuous maintenance of 7 to 10 mm Hg intrabronchial pressure. Five other neonatal animals used as age- and weight-matched controls were killed immediately after distension with PFC to 7 to 10 mm Hg. To evaluate the effect of age on postnatal growth, identical procedures were performed on seven mature sheep. Four adult animals underwent a 21-day distension with PFC, and three animals were killed immediately after PFC distension. RESULTS: Neonatal animals who underwent distension showed a significant acceleration of lung growth based on right upper lobe volume to body weight ratio (P = .0019), total alveolar number (P = .003), and total alveolar surface area (P = .006), when compared with controls. Alveolar growth was attributed to an increased alveolar number rather than increased alveolar size based on a normal histological appearance, normal airspace fraction (P = NS), and normal alveolar numerical density (P = NS). In contrast, no significant differences in lung growth or maturation indices were present in adult animals. CONCLUSIONS: From this preliminary data we conclude: (1) Liquid-based airway distension does accelerate postnatal lung growth, (2) lung architecture remains normal during this period of accelerated growth, (3) adult sheep do not respond to liquid-based airway distension with lung growth, and (4) prolonged exposure to intrapulmonary PFC appears to be safe. We speculate that stretch is the stimulus for lung growth because there are no known growth factors present in PFC.

Animals↗

Current surgical management of congenital diaphragmatic hernia: a report from the Congenital Diaphragmatic Hernia Study Group.

BACKGROUND: Repair of congenital diaphragmatic hernia (CDH) has changed from an emergent procedure to a delayed procedure in the last decade. Many other aspects of management have also evolved since the first successful repair. However, most reports are from single institutions. The lack of a large multicenter database has hampered progress in the management of congenital diaphragmatic hernia (CDH) and makes determination of the current standard difficult. METHODS: The CDH study group was formed in 1995 to collect data from multiple institutions in North America, Europe, and Australia. Participating centers completed a registry form on all live-born infants with CDH during 1995 and 1996. Demographic information, data about surgical management, and outcome were collected for all patients. RESULTS: Sixty-two centers participated, with 461 patients entered. Overall survival was 280 of 442 patients (63%) where survival was recorded. The defect was left-sided in 78%, right-sided in 21%, and bilateral in 1%. A subcostal approach was used in 91% of patients, with pleural drainage used in 76%. A patch of some kind was used in just over half (51%) of the patients, with polytetrafluoroethylene being the most commonly used material (81%) in those patients with a patch. The mean surgical time was 102 minutes, with an average blood loss of 14 mL (range, 0 to 500 mL). The overwhelming majority of patients underwent repair between 6:00 AM and 6:00 PM (289 of 329, 88%). Nineteen percent of patients had surgical repair on extracorporeal membrane oxygenation (ECMO) at a mean time of 170 hours into the ECMO course (range, 10 to 593 hours). The mean age at surgery in patients not treated with ECMO was 73 hours (range, 1 to 445 hours). CONCLUSIONS: The multicenter nature of this report makes it a snapshot of current management. The data would indicate that prosthetic patching of the defect has become common, that after-hours repair is infrequent, and that delayed surgical repair has become the preferred approach in many centers. Furthermore, the mean survival rate of 63% indicates that despite decades of individual effort, the CDH problem is far from solved. This highlights the need for a centralized database and cooperative multicenter studies in the future.

Chi-Square Distribution↗