Severe perineal pain after enterocystoplasty in bladder exstrophy.

OBJECTIVE: To describe a previously unreported complication (severe perineal pain) after bladder reconstruction and enterocystoplasty in patients with bladder exstrophy. PATIENTS AND METHODS: The notes were reviewed retrospectively for four patients (two boys and two girls) with classical bladder exstrophy who had severe penile or perineal pain after bladder reconstruction. They were all continent and using intermittent catheterization. A range of conservative management failed and all patients subsequently required excision of their native bladders between 1997 and 2000. RESULTS: All four patients had perineal or penile pain which began 4 months to 8 years after bladder augmentation. Investigations included plain abdominal X-ray, renal and bladder ultrasonography, computerized tomography of the pelvis, video-urodynamics and cysto-urethroscopy. When therapeutic interventions such as more frequent bladder washouts, analgesic and anticholinergic drugs, and cystolithotomy (two patients) were unsuccessful in alleviating the symptoms, all had their native bladder excised. Histological examination of the excised tissue showed neither normal urothelium nor enteric mucosa at the margins of the excision; two patients already had squamous metaplasia within what represented the bladder, and in the others squamous epithelium was present amongst the enteric mucosa. All four children were pain-free with a follow-up of 2-6 years. CONCLUSION: All four patients developed severe referred bladder pain that was probably secondary to the abnormal retained bladder remnants. Cystectomy cured the pain and may also have removed a potential site of future malignant tumour.

Non-toxic ubiquitous over-expression of utrophin in the mdx mouse.

Duchenne muscular dystrophy (DMD) is an inherited, severe muscle wasting disease caused by the loss of the cytoskeletal protein, dystrophin. Patients usually die in their late teens or early twenties of cardiac or respiratory failure. We have previously demonstrated that the dystrophin related protein, utrophin is able to compensate for the loss of dystrophin in the mdx mouse, the mouse model of the disease. Expression of a utrophin transgene under the control of an HSA promoter results in localization of utrophin to the sarcolemma and prevents the muscle pathology. Here we show that the over-expression of full-length utrophin in a broad range of tissues is not detrimental in the mdx mouse. These findings have important implications for the feasibility of the up-regulation of utrophin in therapy for DMD since they suggest that tissue specific up-regulation may not be necessary.

Amelioration of the dystrophic phenotype of mdx mice using a truncated utrophin transgene.

Duchenne muscular dystrophy (DMD) is a severe, progressive muscle-wasting disease that causes cardiac or respiratory failure and results in death at about 20 years of age. Replacement of the missing protein, dystrophin, using myoblast transfer in humans or viral/liposomal delivery in the mouse DMD model is inefficient and short-lived. One alternative approach to treatment would be to upregulate the closely related protein, utrophin, which might be able to compensate for the dystrophin deficiency in all relevant muscles. As a first step to this approach, we have expressed a utrophin transgene at high levels in the dystrophin-deficient mdx mouse. Our results indicate that high expression of the utrophin transgene in skeletal and diaphragm muscle can markedly reduce the dystrophic pathology. These data suggest that systemic upregulation of utrophin in DMD patients may lead to the development of an effective treatment for this devastating disorder.

G-utrophin, the autosomal homologue of dystrophin Dp116, is expressed in sensory ganglia and brain.

The utrophin gene is closely related to the dystrophin gene in both sequence and genomic structure. The Duchenne muscular dystrophy (DMD) locus encodes three 14-kb dystrophin transcripts in addition to several smaller isoforms, one of which, Dp116, is specific to peripheral nerve. We describe here the corresponding 5.5-kb mRNA from the utrophin locus. This transcript, designated G-utrophin, is of particular interest because it is specifically expressed in the adult mouse brain and appears to be the predominant utrophin transcript in this tissue. G-utrophin is expressed in brain sites generally different from the regions expressing beta-dystroglycan. During mouse embryogenesis G-utrophin is also seen in the developing sensory ganglia. Our data confirm the close evolutionary relationships between the DMD and utrophin loci; however, the functions for the corresponding proteins probably differ.

Trinucleotide repeat amplification and hypermethylation of a CpG island in FRAXE mental retardation.

We have cloned the fragile site FRAXE and demonstrate that individuals with this fragile site possess amplifications of a GCC repeat adjacent to a CpG island in Xq28 of the human X chromosome. Normal individuals have 6-25 copies of the GCC repeat, whereas mentally retarded, FRAXE-positive individuals have > 200 copies and also have methylation at the CpG island. This situation is similar to that seen at the FRAXA locus and is another example in which a trinucleotide repeat expansion is associated with a human genetic disorder. In contrast with the fragile X syndrome, the GCC repeat can expand or contract and is equally unstable when passed through the male or female line. These results also have implications for the understanding of chromosome fragility.

Chinook salmon NADP(+)-dependent cytosolic isocitrate dehydrogenase: electrophoretic and genetic dissection of a complex isozyme system and geographic patterns of variation.

Species in the genus Oncorhynchus express complicated isocitrate dehydrogenase (IDHP) isozyme patterns in many tissues. Subcellular localization experiments show that the electrophoretically distinct isozymes of low anodal mobility expressed predominantly in skeletal and heart muscle are mitochondrial forms (mIDHP), while the more anodal, complex isolocus isozyme system predominant in liver and eye is cytosolic (sIDHP). The two loci encoding sIDHP isozymes are considered isoloci because the most common allele at one of these loci cannot be separated electrophoretically from the most common allele of the other. Over 12 electrophoretically detectable alleles are segregating at the two sIDHP* loci in chinook salmon. Careful electrophoretic comparisons of the sIDHP isozyme patterns of muscle, eye, and liver extracts of heterozygotes reveal marked differences between the tissues with regard to both relative isozyme staining and the expression of several common alleles. Presumed single-dose heterozygotes at the sIDHP isolocus isozyme system exhibit approximate 9:6:1 ratios of staining intensity in liver and eye, while they exhibit approximate 1:2:1 ratios in skeletal muscle. The former proportions are consistent with the equal expression of two loci (isolocus expression), while the latter are consistent with the expression of a single locus. Screening of over 10,000 fish from spawning populations and mixed-stock fishery samples revealed that certain variant alleles (*127, *50) are detectable only in liver and eye, while other alleles (*129, *94, and *74) are strongly expressed in muscle, eye, and liver. The simplest explanation for these observations is that the "isolocus" sIDHP system of chinook salmon (and that of steelhead and rainbow trout) results from the expression of two distinct loci (sIDHP-1* and sIDHP-2*) that have the same common allele (as defined by electrophoretic mobility). IDHP expression in skeletal muscle is due to the nearly exclusive expression of the sIDHP-1* locus, while IDHP expression in eye and liver tissues is due to high levels of expression of both sIDHP-1* and sIDHP-2*--giving rise to the isolocus situation in these latter tissues. Direct inheritance studies confirm this model of two genetically independent (disomic) loci encoding sIDHP in chinook salmon. Extensive geographic surveys of chinook salmon populations from California to British Columbia reveal marked differences in allele frequencies at both sIDHP-1* and sIDHP-2* and considerably more interpopulation differentiation than was recognized previously when sIDHP was treated as an isolocus system with only five recognized alleles.(ABSTRACT TRUNCATED AT 400 WORDS)

Multilocus Electrophoretic Assessment of the Genetic Structure and Diversity of Yersinia ruckeri.

Multilocus isoenzyme electrophoresis was used to screen 47 field isolates of Yersinia ruckeri for electrophoretic variation at 15 enzyme loci. Only four electrophoretic types were observed, thus indicating that the genetic structure of Y. ruckeri is clonal. Forty-two isolates were of one electrophoretic type, a reflection of the low amount of genetic diversity extant in this species. Although sorbitol fermentation has been considered to be indicative of a second biotype, no significant gene frequency differences were found between the group of 20 isolates that readily used sorbitol as the sole carbon source and the group of 27 that did not.

Identification of a gene regulating the tissue expression of a phosphoglucomutase locus in rainbow trout.

Nine percent of the rainbow trout (Salmo gairdneri) from a hatchery source have a greater than 100-fold increase in expression of a phosphoglucomutase (PGM) locus, Pgm1, in the liver but have normal expression of this locus in other tissues. The results of genetic crosses are consistent with a single regulatory gene with additive inheritance being responsible for the differences in the amount of PGM activity in the liver.--The allele responsible for the expression of Pgm1 in the liver is apparently a recent mutation. This is supported by its restricted distribution in rainbow trout and the absence of liver Pgm1 expression in closely related species. This genetic system is valuable for future analysis of the control of gene expression and in determining the relative evolutionary importance of genetic variation at structural and regulatory genes.