[A Rare Cause of Perinatal Postrenal Failure with Megalourethra]. / Seltene Ursache eines Perinatalen Postrenalen Nierenversagens mit Megalourethra.

We present a case of a premature infant with a presumed obstructive uropathy found to be a megalourethra leading to a perinatal postrenal failure. A megalourethra - an uncommon cause of urethral dilatation - is a congenital, non-obstructive anomaly of the penile erectile tissue. We think that a distal stenosis resulted in dysplasia of the penile tissue and an aspect of a megalourethra. Further diagnostic workup included urinary tract sonograms, a voiding cystourethrogram and MAG3 scintigrafy. Initially the patient was managed with supportive care such as a suprapubic urinary catheter, followed by surgical intervention (Bengt Johanson).

Optic chiasm B-cell lymphoma in a 20-month-old Mastiff dog.

A 20-month-old intact female Mastiff dog presented for evaluation of acute blindness. Computed tomography confirmed a tumor involved the optic chiasm and optic nerves. A B-cell lymphoma was confirmed with postmortem examinations. This case report documents a central nervous system neoplasm in a young dog.

Functional implications of novel human acid sphingomyelinase splice variants.

BACKGROUND: Acid sphingomyelinase (ASM) hydrolyses sphingomyelin and generates the lipid messenger ceramide, which mediates a variety of stress-related cellular processes. The pathological effects of dysregulated ASM activity are evident in several human diseases and indicate an important functional role for ASM regulation. We investigated alternative splicing as a possible mechanism for regulating cellular ASM activity. METHODOLOGY/PRINCIPAL FINDINGS: We identified three novel ASM splice variants in human cells, termed ASM-5, -6 and -7, which lack portions of the catalytic- and/or carboxy-terminal domains in comparison to full-length ASM-1. Differential expression patterns in primary blood cells indicated that ASM splicing might be subject to regulatory processes. The newly identified ASM splice variants were catalytically inactive in biochemical in vitro assays, but they decreased the relative cellular ceramide content in overexpression studies and exerted a dominant-negative effect on ASM activity in physiological cell models. CONCLUSIONS/SIGNIFICANCE: These findings indicate that alternative splicing of ASM is of functional significance for the cellular stress response, possibly representing a mechanism for maintaining constant levels of cellular ASM enzyme activity.