Cathodal Transcranial Direct Current Stimulation Over Left Dorsolateral Prefrontal Cortex Area Promotes Implicit Motor Learning in a Golf Putting Task.

© 2015 Elsevier Inc. All rights reserved. Background Implicit motor learning is characterized by low dependence on working memory and stable performance despite stress, fatigue, or multi-tasking. However, current paradigms for implicit motor learning are based on behavioral interventions that are often task-specific and limited when applied in practice. Objective To investigate whether cathodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) area during motor learning suppressed working memory activity and reduced explicit verbal-analytical involvement in movement control, thereby promoting implicit motor learning. Methods Twenty-seven healthy individuals practiced a golf putting task during a Training Phase while receiving either real cathodal tDCS stimulation over the left DLPFC area or sham stimulation. Their performance was assessed during a Test phase on another day. Verbal working memory capacity was assessed before and after the Training Phase, and before the Test Phase. Results Compared to sham stimulation, real stimulation suppressed verbal working memory activity after the Training Phase, but enhanced golf putting performance during the Training Phase and the Test Phase, especially when participants were required to multi-task. Conclusion Cathodal tDCS over the left DLPFC may foster implicit motor learning and performance in complex real-life motor tasks that occur during sports, surgery or motor rehabilitation

Frozen-thawed embryo transfer cycles

Objective: To review the outcomes of frozen-thawed embryo transfer cycles. Design: Retrospective review. Setting: Tertiary assisted reproduction centre, Hong Kong. Patients: Subfertile patients undergoing frozen-thawed embryo transfer between July 2005 and December 2007. Main outcome measures: Clinical and ongoing pregnancy rates. Results: A total of 983 frozen-thawed embryo transfer cycles performed during the study period were reviewed. The clinical pregnancy and ongoing pregnancy rates were 35% and 30%, respectively. Factors associated with successful outcome included younger maternal age (≤35 years) and 4 or more blastomeres at replacement, but not the method of insemination, the cause of subfertility, or the type of frozen-thawed embryo transfer cycle. The overall multiple pregnancy rate was 18%. For cycles with a single embryo replaced, embryos having 4-cell or higher stages at replacement gave an ongoing pregnancy rate of 25%, whereas those with less than 4 cells had a significantly lower ongoing pregnancy rate of 5% only. Blastomere lysis after thawing significantly reduced the clinical pregnancy and ongoing pregnancy rates of cycles with one embryo replaced. Conclusions Clinical pregnancy and ongoing pregnancy rates of frozen-thawed embryo transfer cycles were 35% and 30%, respectively. Higher pregnancy rates were associated with younger maternal age (≤35 years), blastomere numbers of 4 or more, and no blastomere lysis after thawing.published_or_final_versio

MicroRNA-34a is a tumor suppressor in choriocarcinoma via regulation of Delta-like1

Background: Choriocarcinoma is a gestational trophoblastic tumor which causes high mortality if left untreated. MicroRNAs (miRNAs) are small non protein-coding RNAs which inhibit target gene expression. The role of miRNAs in choriocarcinoma, however, is not well understood. In this study, we examined the effect of miR-34a in choriocarcinoma.Methods: MiR-34a was either inhibited or ectopically expressed transiently in two choriocarcinoma cell lines (BeWo and JEG-3) respectively. Its actions on cell invasion, proliferation and colony formation at low cell density were examined. The miR-34a putative target Notch ligand Delta-like 1 (DLL1) was identified by adoption of different approaches including: in-silico analysis, functional luciferase assay and western blotting. Real-time quantitative polymerase chain reaction was used to quantify changes in the expression of matrix proteinase in the treated cells. To nullify the effect of miR-34a ectopic expression, we activated Notch signaling through force-expression of the Notch intracellular domain in the miR-34a force-expressed cells. In addition, we studied the importance of DLL1 in BeWo cell invasion through ligand stimulation and antibody inhibition. Furthermore, the induction in tumor formation of miR-34a-inhibited BeWo cells in SCID mice was investigated.Results: Transient miR-34a force-expression significantly suppressed cell proliferation and invasion in BeWo and JEG-3 cells. In silicon miRNA target prediction, luciferase functional assays and Western blotting analysis demonstrated that miR-34a regulated DLL1 expression in both cell lines. Although force-expression of miR-34a suppressed the expression of DLL1 and NOTCH1, the extent of suppression was higher in DLL1 than NOTCH1 in both cell lines. MiR-34a-mediated DLL1 suppression led to reduced matrix metallopeptidase 9 and urokinase-type plasminogen activator expression. The effect of miR-34a on cell invasion was partially nullified by Notch signaling activation. DLL1 ligand stimulated while anti-DLL1 antibody treatment suppressed cell invasion. Mice inoculated with BeWo cells transfected with miR-34a inhibitor had significantly larger xenografts and stronger DLL1 expression than those with cells transfected with the control inhibitor.Conclusions: MiR-34a reduced cell proliferation and invasiveness, at least, partially through its inhibitory effect on DLL1. © 2013 Pang et al.; licensee BioMed Central Ltd.published_or_final_versio

The use of three-dimensional printing technology in orthopaedic surgery: A review

Three-dimensional (3-D) printing or additive manufacturing, an advanced technology that 3-D physical models are created, has been wildly applied in medical industries, including cardiothoracic surgery, cranio-maxillo-facial surgery and orthopaedic surgery. The physical models made by 3-D printing technology give surgeons a realistic impression of complex structures, allowing surgical planning and simulation before operations. In orthopaedic surgery, this technique is mainly applied in surgical planning especially revision and reconstructive surgeries, making patient-specific instruments or implants, and bone tissue engineering. This article reviews this technology and its application in orthopaedic surgery.published_or_final_versio

Sales rebate contracts in fashion supply chains

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Information inequalities and Generalized Graph Entropies

In this article, we discuss the problem of establishing relations between information measures assessed for network structures. Two types of entropy based measures namely, the Shannon entropy and its generalization, the R\'{e}nyi entropy have been considered for this study. Our main results involve establishing formal relationship, in the form of implicit inequalities, between these two kinds of measures when defined for graphs. Further, we also state and prove inequalities connecting the classical partition-based graph entropies and the functional-based entropy measures. In addition, several explicit inequalities are derived for special classes of graphs.Comment: A preliminary version. To be submitted to a journa

Identification of hip fracture patients from radiographs using Fourier analysis of the trabecular structure: a cross-sectional study

Peer reviewedPublisher PD

Identification of a tyrosine residue responsible for N-acetylimidazole-induced increase of activity of ecto-nucleoside triphosphate diphosphohydrolase 3

Chemical modification in combination with site-directed mutagenesis was used to identify a tyrosine residue responsible for the increase in ecto-nucleoside triphosphate diphosphohydrolase 3 (NTPDase3) nucleotidase activity after acetylation with a tyrosine-selective reagent, N-acetylimidazole. The NTPDase3 ATPase activity is increased more than the ADPase activity by this reagent. Several fairly well conserved tyrosine residues (252, 255, and 262) that are located in or very near apyrase conserved region 4a (ACR4a) were mutated. These mutants were all active, but mutation of tyrosine 252 to either alanine or phenylalanine eliminated the activity increase observed after N-acetylimidazole treatment of the wild-type enzyme. This suggests that the acetylation of tyrosine 252 is responsible for the increased activity. Stabilization of quaternary structure has resulted in increased enzyme activities for the NTPDases. However, mutation of these three tyrosine residues did not result in global changes of tertiary or quaternary structure, as measured by Cibacron blue binding, chemical cross linking, and native gel electrophoretic analysis. Nevertheless, disruption of the oligomeric structure with the detergent Triton X-100 abolished the increase in activity induced by this reagent. In addition, mutations that abolished the N-acetylimidazole effect also attenuated the increases of enzyme activity observed after lectin and chemical cross-linking treatments, which were previously attributed to stabilization of the quaternary structure. Thus, we speculate that the acetylation of tyrosine 252 might induce a subtle conformational change in NTPDase3, resulting in the observed increase in activity

Impact of concomitant thyroid pathology on preoperative workup for primary hyperparathyroidism

BACKGROUND: The former standard surgical treatment in patients with primary hyperparathyroidism (pHPT) has been bilateral cervical exploration. New localization techniques and the possibility of intraoperative measurement of intact parathormone (iPTH) permit a focused, minimally invasive parathyroidectomy (MIP). The introduction of MIP without complete neck exploration leads to the potential risk of missing thyroid pathology. The aim of the present study is to evaluate the value of MIP in respect to coexisting thyroid findings and their impact on preoperative workup for primary hyperparathyroidism. METHODS: This is a prospective study including 30 consecutive patients with pHPT (median age 65 years; 17 females, 13 males). In all patients preoperative localization was performed by ultrasonography and 99m Tc-MIBI scintigraphy- Intraoperative iPTH monitoring was routinely done. RESULTS: Ten patients (33%) had a concurrent thyroid finding requiring additional thyroid surgery, and two patients (7%) with negative localization results underwent bilateral neck exploration. Therefore, MIP was attempted in 18 (60%) patients. The conversion rate to a four gland exploration was 6% (1/18). The sensitivities of 99m Tc-MIBI scanning and ultrasonography were 83.3% and 76.6%, respectively. The respective accuracy rates were 83.3% and 76.6%. Of note, the combination of the two modalities did not improve the sensitivity and accuracy in our patient population. During a median follow-up of 40 months, none of the patients developed persistent or recurrent hypocalcaemia, resulting in a 100% cure rate. CONCLUSION: Coexisting thyroid pathology is relatively frequent in patients with pHPT in our region. Among patients having pHPT without any thyroid pathology, the adenoma localization is correct with either ultrasonography or 99m Tc-MIBI scintigraphy in the majority of cases. MIP with iPTH monitoring are highly successful in this group of patients and this operative technique should be the method of choice