Deciding the Borel complexity of regular tree languages

We show that it is decidable whether a given a regular tree language belongs to the class ${\bf \Delta^0_2}$ of the Borel hierarchy, or equivalently whether the Wadge degree of a regular tree language is countable.Comment: 15 pages, 2 figure

Femoral and tibial bone torsions associated with medial femoro-tibial osteoarthritis. Index of cumulative torsions

AbstractFrontal plane varus deviation is one of the mechanisms hypothesized to be involved in the pathogenesis of medial compartment osteoarthritis of the knee. But only a few authors have suggested a role for tibial and femoral torsion. In the current study, CT scan was used to measure bone torsion. The torsional morphology of the lower limb was defined by the “index of cumulative torsions” (ICT). The resulting values were compared to the frontal angular deviation data. The effects of tibial and femoral torsion on the position of the lower limb during the stance phase of walking and the consequences for the knee are discussed

Reducible valgus flat-foot: Assessment of posterior subtalar joint surface displacement by posterior arthroscopy during sinus tarsi expansion screwing

AbstractIntroductionSubtalar arthroereisis corrects childhood and adult reducible valgus flat-foot in certain indications. Inserting an expansion screw in the sinus tarsi simultaneously corrects the calcaneal valgus of the talocalcaneal divergence and first-ray pronation if these are reducible. The displacement induced in the posterior subtalar joint (decoaptation, translation, rotation) is, however, poorly known. The present study involved arthroscopic assessment of posterior subtalar joint surface displacement during insertion of a talocalcaneal arthroereisis screw, with the hypothesis that displacement varies in three dimensions according to screw size.Material and methodEight specimens were used for the study. All ankles were supple, taken from adult subjects. A 4.5-mm arthroscope was used and measurements were taken with a graduated palpator in the posterior subtalar joint. Three sinus tarsi expansion screws of incremental diameter were assessed. Before and after insertion measurements were made of posterolateral and posteromedial talar exposure on the calcaneus, anteroposterior and lateromedial translation, and talocalcaneal joint-line opening.ResultsMedial rotation, varization and anterior translation of the calcaneus were comparable in all cases. Mean lateral opening of the posterior subtalar joint was 0.88mm with 8-mm screws and 1.25mm with 16-mm screws. Significant differences between 8 and 16mm screws were found for lateral subtalar joint opening (P=0.028) and for lateromedial translation (P=0.004).ConclusionSinus tarsi expansion screwing corrects hindfoot valgus and talocalcaneal divergence by inducing medial translation of the calcaneus under the talus and talar medial rotation and varization, proportional to screw size (medial translation and lateral opening of the subtalar joint).Level of evidenceIII

Complication rates and types of failure after arthroscopic acute acromioclavicular dislocation fixation. Prospective multicenter study of 116 cases

AbstractAimsTo report and analyze both the surgical and radiographic complications associated with anatomic coracoclavicular (CC) ligament procedures and to evaluate the effect of these complications on patient outcomes.Patients and methodsFrom July 2012 to July 2013, 116 primary anatomic CC ligament procedures (all arthroscopic endobutton fixations) were performed in 14 different centers. Demographic, surgical, subjective, and radiographic data were prospectively analyzed in 14 centers with a minimum follow-up of 12 months.ResultsThis series included 96 men and 20 women, mean age 37 years old, with a mean delay to surgery of 10 days. No intraoperative complications were reported. There were 11 complications due to hardware failure resulting in a loss of reduction, 1 coracoid fracture, 7 cases of adhesive capsulitis, 2 local infections, 5 cases of hardware pain. There were significant differences in outcomes between patients who did and did not develop complications: mean CS=71 vs. 93, (P<0.0001). All the parameters of the CS were statistically affected (P<0.0001). Forty-eight patients had persistent dislocation>150% on an AP X-ray which affected the pain and activity CS (P=0.023 and P=0.044). No preoperative predictive factors were identified. These patients could not return to the same level of sports activities due to persistent pain.DiscussionAnatomic procedures to treat AC joint dislocation using CC ligament reconstruction resulted in an overall complication rate of 22.4% and influenced the return to sports. Good to excellent outcomes were reported in patients without complications.Clinical seriesLevel of evidence 4

Ventricular arrhythmias and sudden death in tetralogy of Fallot

Cardiolog

Prognostic factors to succeed in surgical treatment of chronic acromioclavicular dislocations

AbstractIntroductionTreatment of chronic acromioclavicular joint dislocation (ACJD) remains a poorly known and controversial subject. Given the many surgical options, it is not always easy to determine which steps are indispensable.MethodsThis article reports a multicenter prospective study. The clinical and radiological follow-up involved a comparative analysis of the preoperative and postoperative data at 1 year, including pain (visual analogue scale), subjective functional incapacity (QuickDASH), and the objective Constant score, as well as a comparative analysis of vertical and horizontal movements measured on simple x-rays.ResultsBased on a series of 140 operated ACJDs, we included 24 chronic ACJDs. The mean time to surgery was 46 weeks (range, 1 month to 4 years). The patients’ mean age was 41 years, with a majority of males (75%), 72% of whom participated in recreational sports. Professionally, 40% of the subjects had jobs involving manual labor. We noted 40% grade III, 24% grade IV, and 36% grade V injury according to the Rockwood classification. In 92% of cases, coracoclavicular stabilization was provided by a double button implant, reinforced with a biological graft in 88% of the cases. In 29%, millimeters to centimeters of the distal clavicle were resected and acromioclavicular stabilization was associated in 54%. We observed complications in 33% of the cases. At 1 year postoperative, 21 patients underwent clinical and radiological follow-up (87.5%). Only 35% of the patients were satisfied or very satisfied, whereas 100% of them would recommend the operation. Full-time work was resumed in 91% of the cases and all sports could be resumed in 86%. The pre- and postoperative values at 1 year changed as follows: the mean Constant score improved from 61 to 87 (p=0.00002); the subjective QuickDASH score decreased from 41 to 9 (p=0.00002); and radiologically significant reduction of the initial displacement was observed in the vertical plane (p<10−3) and the horizontal plane (p=0.022).ConclusionIn this study, the favorable prognostic factors found were: time to surgery less than 3 months (p=0.02), associated acromioclavicular stabilization, and postoperative immobilization with a sling extended to 6 weeks. However, resection of the distal clavicle did not influence the final result.Level of proofLevel II prospective non-randomized comparative study

Novel lines of Pax6-/- embryonic stem cells exhibit reduced neurogenic capacity without loss of viability

<p>Abstract</p> <p>Background</p> <p>Embryonic stem (ES) cells can differentiate into all cell types and have been used extensively to study factors affecting neuronal differentiation. ES cells containing mutations in known genes have the potential to provide useful in vitro models for the study of gene function during neuronal differentiation. Recently, mouse ES cell lines lacking the neurogenic transcription factor Pax6 were reported; neurons derived from these <it>Pax6</it>^-/-ES cells died rapidly after neuronal differentiation in vitro.</p> <p>Results</p> <p>Here we report the derivation of new lines of <it>Pax6</it>^-/-ES cells and the assessment of their ability to survive and differentiate both in vitro and in vivo. Neurons derived from our new <it>Pax6</it>^-/-lines were viable and continued to elaborate processes in culture under conditions that resulted in the death of neurons derived from previously reported <it>Pax6</it>^-/-ES cell lines. The new lines of <it>Pax6</it>^-/-ES cells showed reduced neurogenic potential, mimicking the effects of loss of Pax6 in vivo. We used our new lines to generate <it>Pax6</it>^-/-↔ <it>Pax6</it>^+/+chimeras in which the mutant cells survived and displayed the same phenotypes as <it>Pax6</it>^-/-cells in <it>Pax6</it>^-/-↔ <it>Pax6</it>^+/+chimeras made by embryo aggregation.</p> <p>Conclusions</p> <p>We suggest that loss of Pax6 from ES cells reduces their neurogenic capacity but does not necessarily result in the death of derived neurons. We offer these new lines as additional tools for those interested in the generation of chimeras and the analysis of in vitro ES cell models of Pax6 function during neuronal differentiation, embryonic and postnatal development.</p

Cardiac safety of dihydroartemisinin-piperaquine and sulfadoxine pyrimethamine among pregnant women with and without asymptomatic parasitaemia in Tanzania: results from an open-label, parallel-group, randomised phase II trial

Background: Dihydroartemisinin-Piperaquine (DP) can induce transient prolongation of the corrected QT interval (QTc) and is a candidate for use with sulfadoxine-pyrimethamine (SP) in intermittent preventive treatment of malaria in pregnancy (IPTp). Pregnancy can alter pharmacokinetics of antimalarial drugs. Acute malaria infection can increase QTc prolongation. Whether DP alters cardiac function in pregnant women with or without asymptomatic parasitaemia is not well characerised. Methods: This was an open-label, parallel-group, randomised phase 2 study among pregnant women in Handeni, Tanzania (NCT02909712). Women were screened for P. falciparum by microscopy and, if positive, received a rapid diagnostic test (RDT). If RDT-positive, they received DP or SP, and the next microscopy-negative woman was randomly allocated to receive DP or SP. Enrolment and allocation continued in this alternating manner to reach 200 (50/group): Grp 1 (neg; SP), Grp 2 (pos; SP), Grp 3 (neg: DP), Grp 4 (pos: DP). Standard 12-lead ECGs were used to record cardiac function in triplicate. DP groups were measured on day 0 (predose), day 2 (predose and hours 3,4,5,6,7,8), and day 7; SP groups had day 0 (predose), and day 7 ECGs. Results: DP resulted in QTcF prolongation that peaked ~30 msec at 5-h post dose 3 on day 2 (schedule: days 0,1,2). The mean maximum increase was slightly more in group 4 compared to group 3 (33.1 vs 29.1 msec). On day 7, QTcF returned to baseline in group 3; a small and non-clinically significant increase of 3.4 (90%CI: 0.3, 6.5) msec was still present among RDT-positive women. QTcB measurements were similar. There was a marked decrease in heart rate (HR) among all DP recipients on day 2, which appeared greater in group 4 compared to group 3 (13.3 vs 8.9 bpm), baseline HR was higher in group 4 than group 3 (92.7 vs 88.5 bpm). This potentially represents a regression towards the mean. On day 7, HR had returned to baseline in both groups. Conclusion: Parasite presence did not alter the effect of DP on the different ECG parameters with the possible exception of HR. No marked differences were observed between pregnant women with and without asymptomatic parasitaemia

Chlorproguanil−Dapsone−Artesunate versus Artemether−Lumefantrine: A Randomized, Double-Blind Phase III Trial in African Children and Adolescents with Uncomplicated Plasmodium falciparum Malaria

Chlorproguanil−dapsone−artesunate (CDA) was developed as an affordable, simple, fixed-dose artemisinin-based combination therapy for use in Africa. This trial was a randomized parallel-group, double-blind, double-dummy study to compare CDA and artemether−lumefantrine (AL) efficacy in uncomplicated Plasmodium falciparum malaria and further define the CDA safety profile, particularly its hematological safety in glucose-6-phosphate dehydrogenase (G6PD) -deficient patients