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BACKGROUND Next-generation DNA sequencing (NGS) techniques have the potential to revolutionize molecular diagnostics; however, a thorough evaluation of these technologies is necessary to ensure their performance meets or exceeds that of current clinical sequencing methods. METHODS We evaluated the NimbleGen Sequence Capture 385K Human Custom Arrays for enrichment of 22 genes. We sequenced each sample on both the Roche 454 Genome Sequencer FLX (GS-FLX) and the Illumina Genome Analyzer II (GAII) to compare platform performance. RESULTS Although the sequence capture method allowed us to rapidly develop a large number of sequencing assays, we encountered difficulty enriching G+C–rich regions. Although a high proportion of reads consistently mapped outside of the targeted regions, >80% of targeted bases for the GAII and >30% of bases for the GS-FLX were covered by a read depth of ≥20, and >90% of bases for the GAII and >80% of bases for the GS-FLX were covered by a read depth of ≥5. We observed discrepancies among sequence variants identified by the different platforms. CONCLUSIONS Although oligonucleotide arrays are quick and easy to develop, some problematic regions may evade capture, necessitating sequential redesigning for complete optimization. Neither sequencing technology was able to detect every variant identified by Sanger sequencing because of well-known drawbacks of the NGS technologies. The rapidly decreasing error rates and costs of these technologies, however, coupled with advancing bioinformatic capabilities, make them an attractive option for molecular diagnostics in the very near future.

Background: We performed a laboratory-based study of the ankle-hindfoot complex in normal cadaveric ankles with simulated lateral ankle ligament injuries, utilizing an ankle stability testing device. The ankle stability testing device distinguished between intact, injury to anterior talofibular ligament (ATFL) and combined injury to ATFL and calcaneofibular ligament (CFL). Materials and Methods: Ankles were tested in an ankle stability testing device, with a specified inversion torque applied through the range of sagittal plane motion, then internal rotation torque applied through the entire range of sagittal plane motion. Three-dimensional motion of the calcaneus and talus in relation to the tibia were determined with a magnetic tracking system. The specimens were tested in the intact condition, then after sectioning the ATFL, then the CFL. Results: Upon sectioning the ATFL, there was a significant increase in the internal rotation motion at the tibiotalar joint. Subsequent sectioning of the CFL did not significantly increase ankle-hindfoot internal rotation, but it did significantly increase the motion in inversion testing. This increase occurred primarily at the tibiotalar level. Conclusion: The isolated ATFL injury was clearly distinguished from the intact condition by increased talar-tibial internal rotation, but not inversion. The more severe combined ATFL/CFL injury was distinguished from the ATFL injury condition with inversion torque. Clinical Relevance: Inversion torque may disclose combined ATFL/CFL injury, and internal rotation torque may be the key to distinguish isolated ATFL and combined ATFL/CFL injuries.

Object Second-generation antiepileptic drugs (AEDs) are increasingly used in the care of patients with glioma. There is little data on how this practice compares with the use of traditional AEDs in this population. This noninferiority analysis compares seizure outcomes and side effects in patients with glioma treated with phenytoin and levetiracetam monotherapy. Methods The authors retrospectively reviewed the records of 500 consecutive patients with glioma who were treated in clinical trials from 2001 to 2008 at 3 Mayo Clinic campuses. To be eligible for the study, these patients had to have had at least 1 clinical seizure and to have undergone follow-up for at least 6 months. Seizure outcomes, defined by the occurrence of a second seizure, time to second seizure, and seizure frequency, along with AED side effects, were compared between cohorts treated with phenytoin or levetiracetam Results Seventy-six patients were identified, 25 treated with phenytoin and 51 with levetiracetam. Sixty-four percent of the patients had a Grade 4 astrocytoma. There was no difference in seizure outcome between the phenytoin and levetiracetam groups when comparing time to second seizure (p = 0.584), second seizure rates (p = 0.561), and average seizures per month (p = 0.776). When adjusting for age, sex, type of seizure, type of glioma, and dosage using univariate and multivariate models, there were no differences between the treatment groups and none of these covariates were statistically significant for explaining the second seizure rates between treatment groups (all p values > 0.05). The incidence of side effects in the levetiracetam group was 6% versus 20% in the phenytoin group (p = 0.106). Additionally, 36% of the patients in the phenytoin group had dose adjustments unrelated to breakthrough seizures compared with only 10% in the levetiracetam group (p = 0.010) Conclusions In this study, patients with glioma treated with levetiracetam and phenytoin had similar seizure control. Patients treated with levetiracetam experienced fewer side effects and required fewer nonseizure-related dose adjustments than patients treated with phenytoin. Levetiracetam is a safe, effective, and preferred alternative for seizure management in patients with glioma.

The vasodilator signals regulating muscle blood flow during exercise are unclear. We tested the hypothesis that in young adults leg muscle vasodilation during steady-state exercise would be reduced independently by sequential pharmacological inhibition of nitric oxide synthase (NOS) and cyclooxygenase (COX) with NG-nitro-l-arginine methyl ester (l-NAME) and ketorolac, respectively. We tested a second hypothesis that NOS and COX inhibition would increase leg oxygen consumption (V̇o2) based on the reported inhibition of mitochondrial respiration by nitric oxide. In 13 young adults, we measured heart rate (ECG), blood pressure (femoral venous and arterial catheters), blood gases, and venous oxygen saturation (indwelling femoral venous oximeter) during prolonged (25 min) steady-state dynamic knee extension exercise (60 kick/min, 19 W). Leg blood flow (LBF) was determined by Doppler ultrasound of the femoral artery. Whole body V̇o2 was measured, and leg V̇o2 was calculated from blood gases and LBF. Resting intra-arterial infusions of acetylcholine (ACh) and nitroprusside (NTP) tested inhibitor efficacy. Leg vascular conductance (LVC) to ACh was reduced up to 53 ± 4% by l-NAME + ketorolac infusion, and the LVC responses to NTP were unaltered. Exercise increased LVC from 4 ± 1 to 33.1 ± 2 ml·min−1·mmHg−1 and tended to decrease after l-NAME infusion (31 ± 2 ml·min−1·mmHg−1, P = 0.09). With subsequent administration of ketorolac LVC decreased to 29.6 ± 2 ml·min−1·mmHg−1 ( P = 0.02; n = 9). While exercise continued, LVC returned to control values (33 ± 2 ml·min−1·mmHg−1) within 3 min, suggesting involvement of additional vasodilator mechanisms. In four additional subjects, LVC tended to decrease with l-NAME infusion alone ( P = 0.08) but did not demonstrate the transient recovery. Whole body and leg V̇o2 increased with exercise but were not altered by l-NAME or l-NAME + ketorolac. These data indicate a modest role for NOS- and COX-mediated vasodilation in the leg of exercising humans during prolonged steady-state exercise, which can be restored acutely. Furthermore, NOS and COX do not appear to influence muscle V̇o2 in untrained healthy young adults.

Purpose The purpose of this study was to document management strategies and complications relating to the use of anteromedial portals for elbow arthroscopy in a series of patients with subluxating or previously transposed ulnar nerves. Methods A review of 913 elbow arthroscopies showed that 59 elbows with a subluxating or previously transposed ulnar nerve required anterior compartment arthroscopic surgery. The patients with subluxating nerves had proximal anteromedial portals established by reducing and holding the nerve behind the epicondyle with a thumb while establishing or entering the portal. In cases of prior nerve transposition, the following techniques were used if, by palpation, localization of the ulnar nerve was considered to be (1) unequivocal, (2) equivocal, or (3) impossible: In group 1 (unequivocal) the proximal anteromedial portal was established in the normal antegrade fashion. In group 2 (equivocal) a 1‐cm incision was made at the planned proximal anteromedial portal site and blunt dissection down to the capsule was performed without identification of the nerve. In group 3 (impossible) a 2‐ to 4‐cm skin incision was made and the nerve was identified before placement of the portal. Results We found that 59 elbows in 56 patients had a subluxating ulnar nerve (31 elbows) or previous ulnar nerve transposition (28 elbows). The transposition had been subcutaneous in 21 and submuscular in 7. The proximal anteromedial portal was used in all but 3 cases (2 patients) of submuscular transposition that were early in the series. In those cases only 2 lateral portals were used for anterior compartment surgery. There were no operative ulnar nerve injuries related to the use of the proximal anteromedial portal. Conclusions Neither elbow arthroscopy nor specifically the use of the proximal anteromedial portal is contraindicated in patients with prior transposition or subluxation of the ulnar nerve. The management of the nerve can be based on the degree of certainty with which the nerve can be localized by palpation in the region of the planned portal. Level of Evidence Level IV, therapeutic case series.