The discovery that mammalian cells have the ability to synthesize the free radical nitric oxide (NO) has stimulated an extraordinary impetus for scientific research in all the fields of biology and medicine. Since its early description as an endothelial-derived relaxing factor, NO has emerged as a fundamental signaling device regulating virtually every critical cellular function, as well as a potent mediator of cellular damage in a wide range of conditions. Recent evidence indicates that most of the cytotoxicity attributed to NO is rather due to peroxynitrite, produced from the diffusion-controlled reaction between NO and another free radical, the superoxide anion. Peroxynitrite interacts with lipids, DNA, and proteins via direct oxidative reactions or via indirect, radical-mediated mechanisms. These reactions trigger cellular responses ranging from subtle modulations of cell signaling to overwhelming oxidative injury, committing cells to necrosis or apoptosis. In vivo, peroxynitrite generation represents a crucial pathogenic mechanism in conditions such as stroke, myocardial infarction, chronic heart failure, diabetes, circulatory shock, chronic inflammatory diseases, cancer, and neurodegenerative disorders. Hence, novel pharmacological strategies aimed at removing peroxynitrite might represent powerful therapeutic tools in the future. Evidence supporting these novel roles of NO and peroxynitrite is presented in detail in this review.

/pdf/nitric-oxide-and-peroxynitrite-in-health-and-disease-3uuuqgfdcz.pdf

Nitric Oxide and Peroxynitrite in Health and Disease

Objective: T o de v elop a North American Society for Pediatric Ga str oen te rol og y , He pat olo gy , and Nut ri tio n (N ASP GH AN) and Eu rop ea n Soc ie ty fo r Pe di atr ic Gas tr oen te ro log y , Hep at ol og y , and Nut rit io n (ES PGH AN ) int er nat io nal con se ns us on th e di agn os is an d ma nag em ent of gas tr oes op hag eal refl ux and gas tr oes op hag eal re flu x di sea se in th e ped ia tr ic po pu la tio n. Methods: An international panel of 9 pediatric gastroenterologists and 2 epidemiologists were selected by both societies, which de v eloped these guidelines based on the Delphi principle. Statements were based on systematic literature searches using the best-av ailable e vidence from PubMed, Cumulati ve Index to Nursing and Allied Health Literature, and bibliographies. The committee con v ened in face-to-face meetings 3 times. Consensus was achie v ed for all recommendations through nominal group technique, a structured, quantitati v e method. Articles were e v aluated using the Oxford Centre for Evidence-based Medicine Le vels of Evidence. Using the Oxford Grades of Recommendation, the quality of e vidence of each of the recommendations made by the committee was determined and is summarized in appendices. Results: More than 600 articles were re vie wed for this work. The document provides e vidence-based guidelines for the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population. Conclusions: Th is do cum ent is int end ed to be us ed in dai ly pra cti ce fo r th e de v el op me nt of fut ure cli ni cal pra ct ic e gu ide lin es and as a bas is for cli ni cal tr ia ls . JP GN 49 :49 8 – 54 7, 20 09 . Ke y Wo rd s: Cli nic al pra ct ic e gu id el ine s — Di agn os tic te sts — Ga str oes op hag ea l refl ux (GE R) — Ga str oes op hag ea l refl ux di sea se (GE RD ) — The rap eut ic mod al iti es. # 20 09 by Eu rop ea n Soc ie ty fo r Pe di atr ic Gas tr oen te ro log y , Hep at ol og y , and Nut rit io n and No rt h Am er ica n So ci ety for Pe dia tri c Ga str oen te rol og y , Hep at ol og y , an d Nu tr iti on

/pdf/pediatric-gastroesophageal-reflux-clinical-practice-359og269ui.pdf

Pediatric Gastroesophageal Reflux Clinical Practice Guidelines: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN)

Here, we demonstrate a role for the mitochondrial NAD-dependent deacetylase Sirt3 in the maintenance of basal ATP levels and as a regulator of mitochondrial electron transport. We note that Sirt3−/− mouse embryonic fibroblasts have a reduction in basal ATP levels. Reconstitution with wild-type but not a deacetylase-deficient form of Sirt3 restored ATP levels in these cells. Furthermore in wild-type mice, the resting level of ATP correlates with organ-specific Sirt3 protein expression. Remarkably, in mice lacking Sirt3, basal levels of ATP in the heart, kidney, and liver were reduced >50%. We further demonstrate that mitochondrial protein acetylation is markedly elevated in Sirt3−/− tissues. In addition, in the absence of Sirt3, multiple components of Complex I of the electron transport chain demonstrate increased acetylation. Sirt3 can also physically interact with at least one of the known subunits of Complex I, the 39-kDa protein NDUFA9. Functional studies demonstrate that mitochondria from Sirt3−/− animals display a selective inhibition of Complex I activity. Furthermore, incubation of exogenous Sirt3 with mitochondria can augment Complex I activity. These results implicate protein acetylation as an important regulator of Complex I activity and demonstrate that Sirt3 functions in vivo to regulate and maintain basal ATP levels.

https://www.pnas.org/content/pnas/105/38/14447.full.pdf

A role for the mitochondrial deacetylase Sirt3 in regulating energy homeostasis

Hirschsprung disease (HSCR, aganglionic megacolon) represents the main genetic cause of functional intestinal obstruction with an incidence of 1/5000 live births. This developmental disorder is a neurocristopathy and is characterised by the absence of the enteric ganglia along a variable length of the intestine. In the last decades, the development of surgical approaches has importantly decreased mortality and morbidity which allowed the emergence of familial cases. Isolated HSCR appears to be a non-Mendelian malformation with low, sex-dependent penetrance, and variable expression according to the length of the aganglionic segment. While all Mendelian modes of inheritance have been described in syndromic HSCR, isolated HSCR stands as a model for genetic disorders with complex patterns of inheritance. The tyrosine kinase receptor RET is the major gene with both rare coding sequence mutations and/or a frequent variant located in an enhancer element predisposing to the disease. Hitherto, 10 genes and five loci have been found to be involved in HSCR development.

/pdf/hirschsprung-disease-associated-syndromes-and-genetics-a-1da3jmvt8r.pdf

Hirschsprung disease, associated syndromes and genetics: a review

PURPOSE: This goal of this research was to develop and evaluate the psychometrics of a health-related quality of life scale developed to address issues related specifically to fecal incontinence, the Fecal Incontinence Quality of Life Scale. METHODS: The Fecal Incontinence Quality of Life Scale is composed of a total of 29 items; these items form four scales: Lifestyle (10 items), Coping/Behavior (9 items), Depression/Self-Perception (7 items), and Embarrassment (3 items). RESULTS: Psychometric evaluation of these scales demonstrates that they are both reliable and valid. Each of the scales demonstrate stability over time (test/retest reliability) and have acceptable internal reliability (Cronbach alpha >0.70). Validity was assessed using discriminate and convergent techniques. Each of the four scales of the Fecal Incontinence Quality of Life Scale was capable of discriminating between patients with fecal incontinence and patients with other gastrointestinal problems. To evaluate convergent validity, the correlation of the scales in the Fecal Incontinence Quality of Life Scale with selected subscales in the SF-36 was analyzed. The scales in the Fecal Incontinence Quality of Life Scale demonstrated significant correlations with the subscales in the SF-36. CONCLUSIONS: The psychometric evaluation of the Fecal Incontinence Quality of Life Scale showed that this fecal incontinence-specific quality of life measure produces both reliable and valid measurement.

https://patientreportedoutcomes2.sites.olt.ubc.ca/files/2014/04/Fecal_Incontinence_Quality_of_Life_Paper.pdf

Lewis Spitz

Papers

Oesophageal atresia: At-risk groups for the 1990s☆

Esophageal atresia: five year experience with 148 cases

Seamless management of biliary atresia in England and Wales (1999-2002).

Esophageal atresia: Lessons I have learned in a 40-year experience

Percutaneous endoscopic gastrostomy in paediatric practice: Complications and outcome