Blood loss in primary total knee arthroplasty-body temperature is not a significant risk factor-a prospective, consecutive, observational cohort study

BACKGROUND: Hypothermia related to anaesthesia and operating theatre environment is associated with increased blood loss in a number of surgical disciplines, including total hip arthroplasty. The influence of patient temperature on blood loss in total knee arthroplasty (TKA) has not been previously studied. METHODS: We recorded patient axillary temperature in the peri-operative period, up to 24 h post-operatively, and analysed the effect on transfusion rate and blood loss from a consecutive cohort of 101 patients undergoing primary TKA. RESULTS: No relationship between peri-operative patient temperature and blood loss was found within the recorded patient temperature range of 34.7–37.8 °C. Multivariable analysis found increasing age, surgical technique, type of anaesthesia and the use of anti-platelet and anticoagulant medications as significant factors affecting blood loss following TKA. CONCLUSION: Patient temperature within a clinically observed range does not have a significant impact on blood loss in primary TKA patients. As long as patient temperature is maintained within a reasonable range during the intra-operative and post-operative periods, strategies other than rigid temperature control above 36.5 °C may be more effective in reducing blood loss following TKA

Structural characterization of intrinsically disordered proteins by NMR spectroscopy.

Recent advances in NMR methodology and techniques allow the structural investigation of biomolecules of increasing size with atomic resolution. NMR spectroscopy is especially well-suited for the study of intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) which are in general highly flexible and do not have a well-defined secondary or tertiary structure under functional conditions. In the last decade, the important role of IDPs in many essential cellular processes has become more evident as the lack of a stable tertiary structure of many protagonists in signal transduction, transcription regulation and cell-cycle regulation has been discovered. The growing demand for structural data of IDPs required the development and adaption of methods such as 13C-direct detected experiments, paramagnetic relaxation enhancements (PREs) or residual dipolar couplings (RDCs) for the study of 'unstructured' molecules in vitro and in-cell. The information obtained by NMR can be processed with novel computational tools to generate conformational ensembles that visualize the conformations IDPs sample under functional conditions. Here, we address NMR experiments and strategies that enable the generation of detailed structural models of IDPs

Arginine Vasotocin and Cortisol Co-regulate Vasotocinergic, Isotocinergic, Stress, and Thyroid Pathways in the Gilthead Sea Bream (Sparus aurata)

In teleosts, a complex interaction between several endocrine axes modulates physiological functions related to metabolism, stress, and osmoregulation. Although many studies in fish underline the interconnection between the hypothalamic– pituitary–interrenal (HPI) and hypothalamic–pituitary–thyroid (HPT) endocrine axes, their relationship with the vasotocinergic and isotocinergic systems remains unknown. The aim of the present study is therefore to shed light on the potential cross-regulations between HPT, HPI, and the vasotocinergic and isotocinergic axes in gilthead sea bream (Sparus aurata) at hypothalamic, hypophyseal, and plasma levels. Sea breams were administered with intraperitoneal slow-release implants containing different doses of vasotocin (the active peptide in vasotocinergic system) or cortisol (the last component of HPI axis). Plasma osmolality was higher in active neuropeptides vasotocin (Avt)- treated fish, indicating an osmoregulatory function of this hormone. Low concentrations of Avt increased hypothalamic arginine vasotocin precursor (avt) mRNA levels and increased Avt storage in the pituitary. Avt treatment down-regulated hypothalamic arginine vasotocin receptor v1a-type (avtrv1a), suggesting a negative paracrine coregulation of the HPI axis due to the close location of avtrv1a and adrenocorticotropin hormone (Acth) cells in the anterior pituitary. Furthermore, the up-regulation observed in arginine vasotocin receptor v2-type (avtrv2) suggests their involvement in metabolic and cortisol-related pathways in the hypothalamus. The decrease in isotocin (It) pituitary storage and the up-regulation of it receptor, observed in the Avt-treated group, reinforce the idea of an interconnection between the vasotocinergic and isotocinergic systems. Cortisol and Avt administration each inhibited the HPI axis, down-regulating crh gene expression in the absence of variations in corticotropin releasing hormone binding protein (crhbp). Finally, both hormonal treatments activated the HPT axis via upregulation of trh and down-regulation of thrb. Our results provide evidence for strong interactions among the Avt/It, HPI, and HPT axes of marine teleosts, particularly at the hypothalamic level

A Formylglycine-Peptide for the Site-Directed Identification of Phosphotyrosine-Mimetic Fragments

Discovery of protein-binding fragments for precisely defined binding sites is an unmet challenge to date. Herein, formylglycine is investigated as a molecular probe for the sensitive detection of fragments binding to a spatially defined protein site . Formylglycine peptide 3 was derived from a phosphotyrosine-containing peptide substrate of protein tyrosine phosphatase PTP1B by replacing the phosphorylated amino acid with the reactive electrophile. Fragment ligation with formylglycine occurred in situ in aqueous physiological buffer. Structures and kinetics were validated by NMR spectroscopy. Screening and hit validation revealed fluorinated and non-fluorinated hit fragments being able to replace the native phosphotyrosine residue. The formylglycine probe identified low-affinity fragments with high spatial resolution as substantiated by molecular modelling. The best fragment hit, 4-amino-phenyl-acetic acid, was converted into a cellularly active, nanomolar inhibitor of the protein tyrosine phosphatase SHP2

PBL3.0:Integrating Learning Analytics and Semantics in Problem-Based Learning

This paper presents the PBL3.0 project that aims at enhancing Problem Based Learning (PBL) with Learning Analytics (LA) and Learning Semantics (LS) in order to produce a new educational paradigm and pilot it to produce relevant policy recommendations. To this end, the project will reach the following objectives and corresponding specific goals: 1) Construct a new educational approach that combines a well-established learning strategy like PBL with novel technologies in learning like LA in PBL respecting legal and ethical considerations (PBL_LA), 2) Design a semantic model for PBL_LA, which will enable the annotation of learning resources in order to easily integrate them to the PBL approach and enable their discoverability when setting personalized learning pathways, 3) Adapt a set of open source software tools for supporting PBL_LA and the semantic model based on existing Learning Management Systems, analytics tools, and an intuitive semantic annotation tool, 4) Create relevant, semantically annotated educational material and perform trials at various sites in order to draw evidence-based conclusions, 5) Produce relevant policy recommendations for PBL_LA that could raise the quality in education and training, 6) Create an organic ecosystem of among others organizations, researchers, educators, students with an interest in PBL_LA. Finally, the project will develop a Community of Practice, where institutions and individuals from across Europe will be able to exchange knowledge and expertise on LA, learning semantics, innovative learning tools and approaches. This aims to support transnational cooperation and mutual learning on forward-looking issues between key stakeholders to provide solutions to current challenges in education and training

Az Interkulturális Érzékenység Skála magyar változatának pszichometriai vizsgálata orvostanhallgatók és pszichológia szakos hallgatók mintáján

Háttér és célkitűzések: Az egyre növekvő kulturális diverzitás következtében az utóbbi évek nemzetközi és hazai tudományos irodalma egyre több figyelmet fordít az interkulturális kompetencia mérési és fejlesztési feladataira a gyógyításban. Jelen vizsgálatban célunk az Interkulturális Érzékenység Skála magyar változatának pszichometriai vizsgálata orvostan- és pszichológushallgatók körében, feltárva emellett az empátiával való konvergens validitását és a skálán különböző demográfiai változók mentén megjelenő különbségeket és együtt járásokat. Módszer: A kvantitatív, keresztmetszeti vizsgálatban 396 magyar, gyógyító szakmára készülő hallgató demográfiai és Interkulturális Érzékenység Skála, valamint Interperszonális Reaktivitás Index adatait elemeztük. Az eredeti 5 faktoros kérdőívstruktúra érvényességi és megbízhatósági vizsgálatai mellett korreláció, független mintás t-próba, egyutas ANOVA teszteket és lineáris regressziót alkalmaztunk. Eredmények: Az eredeti skála nem mutatott megfelelő és érvényes illeszkedést magyar mintán, helyette egy alternatív, rövidített, 3 faktoros struktúra bizonyult a legjobban illeszkedőnek, elfogadható vagy jó belső megbízhatósági mutatókkal. Eredményeink szerint a nyelvismeret és az empátia két dimenziója jelentős bejóslója az interkulturális érzékenységnek: a perspektíva- felvétel pozitívan, a személyes distressz pedig fordított irányban jelezte azt előre. Következtetések: Egy olyan magyar nyelvre adaptált mérőeszközt alakítottunk ki, mely megbízhatóan méri a magyar gyógyító szakmára készülők interkulturális érzékenységét. E készség fejlesztése napjainkban az egészségügyi képzések fontos feladata. A hallgatók nyelvtanulásának, kultúrközi tapasztalatszerzésének és empátiafejlesztésének támogatása mellett az interdiszciplináris és interkulturális felépítésű gyógyítói tanuló- vagy kutatócsoportok igen hasznos együtt- működésének irányába mutatnak a jelen kutatás eredményei

Peptide-oligonucleotide conjugates as nanoscale building blocks for assembly of an artificial three-helix protein mimic

Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide–oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design

Natural history of perinatal and infantile hypophosphatasia: A retrospective study

Objective: To report clinical characteristics and medical history data obtained retrospectively for a large cohort of pediatric patients with perinatal and infantile hypophosphatasia. Study design: Medical records from academic medical centers known to diagnose and/or treat hypophosphatasia were reviewed. Patients born between 1970 and 2011 with hypophosphatasia and any of the following signs/symptoms at age <6 months were eligible: vitamin B6–dependent seizures, respiratory compromise, or rachitic chest deformity (NCT01419028). Patient demographics and characteristics, respiratory support requirements, invasive ventilator–free survival, and further complications of hypophosphatasia were followed for up to the first 5 years of life. Results: Forty-eight patients represented 12 study sites in 7 countries; 13 patients were alive, and 35 were dead (including 1 stillborn). Chest deformity, respiratory distress, respiratory failure (as conditioned by the eligibility criteria), failure to thrive, and elevated calcium levels were present in >70% of patients between birth and age 5 years. Vitamin B6–dependent seizures and respiratory distress and failure were associated significantly (P <.05)with the risk of early death. Serum alkaline phosphatase activity in all 41 patients tested (mean [SD]: 18.1 [15.4]U/L)was below the mean lower limit of normal of the reference ranges of the various laboratories (88.2 U/L). Among the 45 patients with relevant data, 29 had received respiratory support, of whom 26 had died at the time of data collection. The likelihood of invasive ventilator–free survival for this cohort decreased to 63% at 3 months, 54% at 6 months, 31% at 12 months, and 25% at 5 years. Conclusions: Patients with perinatal or infantile hypophosphatasia and vitamin B6–dependent seizures, with or without significant respiratory distress or chest deformities, have high morbidity and mortality in the first 5 years of life. Trial registration: ClinicalTrials.gov: NCT01419028

Quantification of Intrinsically Disordered Proteins: A Problem Not Fully Appreciated

Protein quantification is essential in a great variety of biochemical assays, yet the inherent systematic errors associated with the concentration determination of intrinsically disordered proteins (IDPs) using classical methods are hardly appreciated. Routinely used assays for protein quantification, such as the Bradford assay or ultraviolet absorbance at 280 nm, usually seriously misestimate the concentrations of IDPs due to their distinct and variable amino acid composition. Therefore, dependable method(s) have to be worked out/adopted for this task. By comparison to elemental analysis as the gold standard, we show through the example of four globular proteins and nine IDPs that the ninhydrin assay and the commercial QubitTM Protein Assay provide reliable data on IDP quantity. However, as IDPs can show extreme variation in amino acid composition and physical features not necessarily covered by our examples, even these techniques should only be used for IDPs following standardization. The far-reaching implications of these simple observations are demonstrated through two examples: (i) circular dichroism spectrum deconvolution, and (ii) receptor-ligand affinity determination. These actual comparative examples illustrate the potential errors that can be incorporated into the biophysical parameters of IDPs, due to systematic misestimation of their concentration. This leads to inaccurate description of IDP functions