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OBJECTIVES: The purpose of this study was to determine the accuracy of a commonly used veterinary wire tensioner. METHODS: Wire tension was measured using a load cell after each of five tensioners were used to tension each of six wires to the 66, 84, and 118 mm ring settings in an adjustable custom testing fixture. Each tensioner then experienced simulated aging and testing was repeated. Percentage error was calculated for each ring size, before and after tensioner aging. Measured tension values were compared to manufacturer reported tension values for each ring size using a one-sample two-way t-test; p <0.05 was considered significant. RESULTS: Compared to the manufacturer reported values, measured wire tension values were significantly lower for 66 mm and 84 mm rings and significantly higher for 118 mm rings, before and after simulated aging. Mean wire tension values did not significantly differ between individual wire tensioners. CLINICAL SIGNIFICANCE: The tensioners tested achieved significantly different wire tension values than those reported by the manufacturer. This discrepancy could lead to under-tensioning and allowing excessive movement at a fracture site or over-tensioning, leading to wire breakage. We recommend tensioning wires at least to the recommended line on the device for 66 mm and 84 mm rings and at most to the recommended line for 118 mm rings. Further studies are needed to evaluate other veterinary wire tensioners and to develop a calibration method for these devices in practice.

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Compared with countries worldwide, the United States currently has one of the lowest peritoneal dialysis (PD) populations as compared with its hemodialysis (HD) population. Approximately 12% of the total dialysis population in the United State is on PD. This figure correlates with the take-on rate [percentage of end-stage renal disease (ESRD) patients enrolling in PD programs] of about 12%-15% in the United States. Over a two-year period, we prospectively examined the role that developing a comprehensive infrastructure and support system had on expanding our PD program. The changes made included these: nephrologists placing PD catheters using the laparoscopic method; active identification of, and training for, family members and personnel in nursing homes and daycare centers to perform PD; improvements in home conditions through support by social workers; early ESRD patient education; and provision of in-center intermittent PD (IPD) for selected patients. We then compared the results from the two years after commencement of the changes against the two years before the changes were made. Training of personnel in nursing homes increased enrollment from 3 to 11 patients (p = 0.01); training of personnel in daycare centers increased enrollment from 0 to 5 patients (p = 0.05); training family members and providing family support increased enrollment from 4 to 15 patients (p = 0.03); early patient and family education increased enrollment from 4 to 24 patients (p = 0.008); improving home conditions increased enrollment from 1 to 14 patients (p = 0.01); and providing an IPD program for selected patients added 6 patients (p = 0.05). Introducing a program for nephrologists to place PD catheters by the laparoscopic technique decreased catheter mechanical failure (and subsequent transfer to HD), from 22 to 3 patients (p = 0.005). Our PD take-on rate (percentage of ESRD patients choosing PD modality) increased from 19% to 76% (p = 0.002). The total number of patients in the PD program over the two years after initiation of the changes increased from 33 to 93 (p = 0.01), while the number of HD patients decreased from 168 to 142 (p = 0.05). Developing a comprehensive infrastructure and support system for PD programs permits enrollment of patients who otherwise would have been excluded as PD candidates and eliminates loss of PD patients to HD. Implementation of such programs can contribute considerably to enhancing the PD population growth rate.

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Intraperitoneal (i.p.) bleeding causes intense inflammatory reactions and extensive adhesions. The relationship between i.p. bleeding and adhesions is well documented in both animal and human studies. Over an 8-year period, we performed 362 permanent peritoneal dialysis (PD) catheter placements in 317 patients, using the laparoscopic technique. In the first 203 procedures (group I), we observed intra-operative bleeding in 12 patients (intra-operative i.p. bleeding seen laparoscopically, and significant blood-tinged dialysate irrigation). Patients were left dry for 3-5 days before dialysate instillation during the break-in period. During the break-in period, 7 of the 12 patients (58%) developed primary catheter failure requiring catheter removal (p = 0.03). All 7 patients underwent repeat laparoscopy for placement of a new catheter. In all 7 patients, laparoscopy showed significant adhesions. In the subsequent 159 procedures (group II), we observed intra-operative bleeding in 10 patients. We irrigated the peritoneal cavity repeatedly, until clear dialysate was obtained, then instilled 500-1000 mL 1.5% Dianeal solution (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.) and capped the catheter. These patients were then placed on low-volume continuous cycling peritoneal dialysis [(CCPD) 700-1200 mL, based on the patient's size, every 2 hours, until the effluent became clear]. Following this, patients underwent daily irrigation and PD fluid cell count, and were left with 700-1200 mL dialysate to dwell. The process was continued until PD fluid drainage showed no red blood cells or until the patient was started on routine peritoneal dialysis. None of these patients were drained dry. Compared with group I, no patient among the 10 in group II developed catheter failure (p = 0.001), and mean catheter survival was 31 +/- 7 months. Of the 10 patients, 2 developed exist-site leaks, both after clearance of red blood cells from the drained dialysate. None developed peritonitis. We conclude that intra-operative i.p. bleeding associated with significant blood-tinged dialysate irrigation may lead to local adhesions if the peritoneum is drained dry. The result may be loss of the PD catheter in about 60% of cases. Continuous irrigation, combined with a moderate amount of Dianeal solution left to dwell, or early initiation of low-volume PD, or both, prevents this complication.

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The synuclein family of proteins is a group of primarily brain-expressed polypeptides that show a high degree of amino acid conservation. alpha-Synuclein is the best known of the synuclein family, as it is a major component of the Lewy body, a cytoplasmic inclusion characteristic of Parkinson's disease as well as a variety of related neurodegenerative disorders. With the discovery that mutations in alpha-synuclein can cause Parkinson's disease, a potential role for the other synuclein family members in neurodegenerative disease is being considered. beta-Synuclein in particular may deserve special attention, as it is co-expressed with alpha-synuclein at presynaptic nerve terminals, is subject to phosphorylation by Ca(2+) calmodulin protein kinase II, appears important for neural plasticity, and forms aggregates in the brains of patients with Parkinson's disease and a related disorder. To facilitate study of beta-synuclein, we have cloned the mouse beta-synuclein gene (Sncb) and determined its genomic organization, size, and intron-exon structure. Using an interspecific backcross mapping panel from The Jackson Laboratory, we were then able to localize Sncb to chromosome 13 at the MGD 35.0 cM position. Like the human beta-synuclein gene, Sncb appears to consist of six exons separated by five introns. Unlike the human beta-synuclein gene, the mouse ortholog possesses a variant GC 5' splice donor sequence at the exon 4 - intron 4 boundary in a highly conserved splice junction consensus. Northern blot analysis and Western blot analysis both indicate that Sncb is highly expressed in the brain. Knowledge of the genomic organization and expression pattern of Sncb will allow functional studies of its potential role in neurodegeneration to commence in the mouse.

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Production of mouse models of inherited neurodegenerative diseases is an important step towards understanding the mechanism of neurotoxicity and for testing potential therapies. We are interested in creating a mouse model for X-linked spinal and bulbar muscular atrophy (SBMA), a neuromuscular disorder caused by expansion of a CAG repeat within the androgen receptor (AR) gene. To permit generation of mice that will show a SBMA phenotype within their life span, we decided to obtain a yeast artificial chromosome (YAC) carrying the AR gene and introduce CAG repeat mutations numbering 100 or more triplets. SBMA patients with more than 70 CAGs have never been observed; therefore, we chose to expand a 59 CAG repeat tract in vivo in Escherichia coli. Although we set out to expand this repeat tract using a recombination paradigm involving two plasmid co-propagation, we did not observe large expansions. We were instead able to incrementally generate repeat tracts from 100 to 200 CAGs in a yeast integrating plasmid vector by taking advantage of replication instability. In the course of our experiments that yielded these CAG repeat tracts, we evaluated the role of repeat orientation, vector co-propagation, and recA function on the expansion process. We then used one of the yeast integrating vectors to successfully produce an AR YAC construct carrying 100 CAG repeats. AR YAC CAG100 will serve as a valuable reagent for the production of a SBMA mouse.

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We report a rare case of massive bilateral staghorn calculi in a spinal cord injury patient with significant renal compromise. The patient was successfully treated with percutaneous nephrolithotomy to achieve a stone-free status. The various options of treatment are discussed with special attention to the technical aspects necessary to achieve complete eradication of the stone burden during percutaneous nephrolithotomy. Furthermore, the importance of treating bladder dysfunction and urinary metabolic abnormalities is emphasized.

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Prevalence of symptomatic benign prostatic hypertophy (BPH) is 30% in the sixth decade of life and approaches 50% in the eighth decade of life. Comparable prevalence values are reported in Occidental and Oriental cultures, which suggests the disease susceprible to neither environmental nor cultural favoritism. "Prostatism" is the descriptive word for the BPH constellation of symptoms, which appear as a result of bladder outlets obstructed by an enlarged prostate. In traditional prostatism, prostate growth has a benign etiology. These urologie symptoms may be either irritative (difficulty postponing urination, frequent awakenings at night for urination), obstructive (weak stream, hesitancy), or both. In the context of so much morbidity associated with the BPH symptom complex, this disease is arguably the most bothersome disease for the elderly male. With improvements in healthcare, and with men having longer life expectancies, there is the appreciation of an expanded patient population. It has become possible to heat the prostate with radiofrequency energy (RF) to relieve symptoms associated with BPH using a heating technique called "transurethral needle ablation of the prostate" (TUNA). By both subjective and objective criteria, TUNA theraphy to the prostate for BPH compares favorably with traditional surgical treatment. Now the durability of the TUNA treatment is demonstrated beyond three years.

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The majority of patients with secondary hyperparathyroidism caused by chronic renal insufficiency are successfully managed medically. However, approximately 5-10 per cent develop refractory symptoms such as bone pain and pruritus requiring palliative surgical treatment. We present a series of 16 consecutive patients who were managed with sub-total parathyroidectomy over a 6-year period. With follow-up of 12-60 months, there were no operative mortalities or significant perioperative morbidities. All patients had significant improvement or resolution of their symptoms. All had biochemical improvement with reductions in their serum calcium and parathormone levels. No patients have required re-exploration for persistent or recurrent hyperparathyroidism, and there have been no cases of permanent hypoparathyroidism. We feel that sub-total parathyroidectomy remains the optimal treatment for refractory secondary hyperparathyroidism. It offers several advantages over total parathyroidectomy with autotransplantation.

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Traumatic dislocation of the testicle is a rare injury generally resulting from severe scrotal trauma and displacement of the testicle into the subcutaneous tissue surrounding the external inguinal ring. The authors report here the extremely unusual case of an abdominal dislocation of the testicle in a young patient with an indirect inguinal hernia. In addition this case is particularly atypical in that the injury resulted from a trivial blow to the scrotum. A new mechanism involving preloading of the cremaster muscle as the source of the dislocation is postulated.

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