Defining normal neonatal abdominal wall musculature with ultrasonography.

INTRODUCTION: The development of new surgical approaches for the management of congenital abdominal wall defects may be facilitated by using an animal model. However, because the anatomy of the neonatal abdominal wall has not been described, a suitable model is yet to be identified. We aimed to evaluate and define the neonatal abdominal wall musculature using ultrasound, to be used as a reference to identify an appropriate animal model for the neonatal abdominal wall in the future. METHODS: Infants with a postconceptual age of less than one month weighing between 2 and 3 kg were eligible. With ethical approval, ultrasonography of three abdominal wall locations bilaterally was performed. The depth of the skin to external oblique and the thickness of the three abdominal wall muscles, external oblique (EO), internal oblique (IO) and transversus abdominis (TA), were measured. RESULTS: Ten males and seven females were recruited with median postconceptual age of 36 weeks (IQR 36-38), median postnatal age of 8 days (IQR 3-30) and median weight of 2.35kg (IQR 2.26-2.56). The mean depth of EO from skin was 2.06 mm (± 0.44). The mean thicknesses of the muscles were: EO 1.02 mm (± 0.33), IO 1.16 mm (± 0.39) and TA 1.02 mm (± 0.37). There was no statistical difference between the thickness of EO, IO or TA (p= 0.43). CONCLUSIONS: It is possible to consistently identify and measure the components of the neonatal abdominal wall musculature with ultrasonography. We hope this can aid in developing an appropriate animal model, with the ultimate aim of facilitating innovation in surgical management of neonatal abdominal wall pathology. LEVELS OF EVIDENCE: Study of Diagnostic test, Level IV.

Enhanced Repair of UV-Induced DNA Damage by 1,25-Dihydroxyvitamin D3 in Skin Is Linked to Pathways that Control Cellular Energy.

Inadequately repaired post-UV DNA damage results in skin cancers. DNA repair requires energy but skin cells have limited capacity to produce energy after UV insult. We examined whether energy supply is important for DNA repair after UV exposure, in the presence of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), which reduces UV-induced DNA damage and photocarcinogenesis in a variety of models. After UV exposure of primary human keratinocytes, the addition of 1,25(OH)2D3 increased unscheduled DNA synthesis, a measure of DNA repair. Oxidative phosphorylation was depleted in UV-irradiated keratinocytes to undetectable levels within an hour of UV irradiation. Treatment with 1,25(OH)2D3 but not vehicle increased glycolysis after UV. 2-Deoxyglucose-dependent inhibition of glycolysis abolished the reduction in cyclobutane pyrimidine dimers by 1,25(OH)2D3, whereas inhibition of oxidative phosphorylation had no effect. 1,25(OH)2D3 increased autophagy and modulated PINK1/Parkin consistent with enhanced mitophagy. These data confirm that energy availability is limited in keratinocytes after exposure to UV. In the presence of 1,25(OH)2D3, glycolysis is enhanced along with energy-conserving processes such as autophagy and mitophagy, resulting in increased repair of cyclobutane pyrimidine dimers and decreased oxidative DNA damage. Increased energy availability in the presence of 1,25(OH)2D3 is an important contributor to DNA repair in skin after UV exposure.

An experimental study of optimal parameters for bipolar electrocoagulation.

The role of artery diameter, probe force application (94, 250 or 491 g), coagulation time (2, 10, or 20 secs) and BICAP generator output (5, 10) were studied in rabbit arteries of 3 to 5 mm hemicircumference. Arterial welds were then tested to destruction by increasing intraluminal pressure. The best arterial welds were achieved by the highest force and coagulation time; high generator output did not improve weld strength. These in vitro experiments suggest that when treating a bleeding peptic ulcer, BICAP therapy should be done with a low generator output of 5 or less, for at least 20 seconds per site, and with as great a compression force as possible. (Gastrointest Endosc 1995;42:27-30.).

Prevention of heart failure in the management of congenital diaphragmatic hernia by maintaining ductal patency. A case report.

Congenital diaphragmatic hernia is a rare entity in childhood carrying a high mortality rate of 30% to 50%. Ipsilateral pulmonary hypoplasia, increased pulmonary vascular resistance, and potential cardiac failure complicate early postnatal life. Surgical correction can either be performed on the first day of life or be deferred to a time after stabilization of the infant. Our patient presented with a left-sided Bochdalek's hernia containing large and small bowel. She required intubation and resuscitation on day 1 of life, and surgical repair had to be postponed. Further respiratory deterioration required commencement of inhaled nitric oxide and high-frequency ventilation. Pulmonary artery pressure rose to suprasystemic level. Closure of the ductus arteriosus on day 8 resulted in imminent right-sided heart failure. Commencement of alprostadil (prostaglandin E1) reopened the ductus and stabilized the patient. Surgical repair was successful 3 days later. Alprostadil should be considered as an important component of therapy in severe cases of congenital diaphragmatic hernia, where deterioration of right-sided heart function occurs.