181 research outputs found
Ruthenacycles and Iridacycles as Catalysts for Asymmetric Transfer Hydrogenation and Racemisation
Ruthenacycles, which are easily prepared in a single step by reaction between enantiopure aromatic amines and [Ru(arene)Cl2]2 in the presence of NaOH and KPF6, are very good asymmetric transfer hydrogenation catalysts. A range of aromatic ketones were reduced using isopropanol in good yields with ee’s up to 98%. Iridacycles, which are prepared in similar fashion from [IrCp*Cl2]2 are excellent catalysts for the racemisation of secondary alcohols and chlorohydrins at room temperature. This allowed the development of a new dynamic kinetic resolution of chlorohydrins to the enantiopure epoxides in up to 90% yield and 98% enantiomeric excess (ee) using a mutant of the enzyme Haloalcohol dehalogenase C and an iridacycle as racemisation catalyst.
Evaluation of the zucker diabetic fatty (ZDF) rat as a model for human disease based on urinary peptidomic profiles
Representative animal models for diabetes-associated vascular complications are extremely relevant in assessing potential therapeutic drugs. While several rodent models for type 2 diabetes (T2D) are available, their relevance in recapitulating renal and cardiovascular features of diabetes in man is not entirely clear. Here we evaluate at the molecular level the similarity between Zucker diabetic fatty (ZDF) rats, as a model of T2D-associated vascular complications, and human disease by urinary proteome analysis. Urine analysis of ZDF rats at early and late stages of disease compared to age- matched LEAN rats identified 180 peptides as potentially associated with diabetes complications. Overlaps with human chronic kidney disease (CKD) and cardiovascular disease (CVD) biomarkers were observed, corresponding to proteins marking kidney damage (eg albumin, alpha-1 antitrypsin) or related to disease development (collagen). Concordance in regulation of these peptides in rats versus humans was more pronounced in the CVD compared to the CKD panels. In addition, disease-associated predicted protease activities in ZDF rats showed higher similarities to the predicted activities in human CVD. Based on urinary peptidomic analysis, the ZDF rat model displays similarity to human CVD but might not be the most appropriate model to display human CKD on a molecular level
First report of generalized face processing difficulties in möbius sequence.
Reverse simulation models of facial expression recognition suggest that we recognize the emotions of others by running implicit motor programmes responsible for the production of that expression. Previous work has tested this theory by examining facial expression recognition in participants with Möbius sequence, a condition characterized by congenital bilateral facial paralysis. However, a mixed pattern of findings has emerged, and it has not yet been tested whether these individuals can imagine facial expressions, a process also hypothesized to be underpinned by proprioceptive feedback from the face. We investigated this issue by examining expression recognition and imagery in six participants with Möbius sequence, and also carried out tests assessing facial identity and object recognition, as well as basic visual processing. While five of the six participants presented with expression recognition impairments, only one was impaired at the imagery of facial expressions. Further, five participants presented with other difficulties in the recognition of facial identity or objects, or in lower-level visual processing. We discuss the implications of our findings for the reverse simulation model, and suggest that facial identity recognition impairments may be more severe in the condition than has previously been noted
Improvement of lower extremity electrodiagnostic findings following a trial of spinal manipulation and motion-based therapy
BACKGROUND: Lumbar disc herniation is a problem frequently encountered in manual medicine. While manual therapy has shown reasonable success in symptomatic management of these cases, little information is known how manual therapy may affect the structure and function of the lumbar disc itself. In cases where lumbar disc herniation is accompanied by radicular symptoms, electrodiagnostic testing has been used to provide objective clinical information on nerve function. This report examines the treatment rendered for a patient with lower extremity neurological deficit, as diagnosed on electrodiagnostic testing. Patient was treated using spinal manipulation and exercises performed on a Pettibon Wobble Chair™, using electrodiagnostic testing as the primary outcome assessment. CASE PRESENTATION: An elderly male patient presented to a private spine clinic with right-sided foot drop. He had been prescribed an ankle-foot orthosis for this condition. All sensory, motor, and reflex findings in the right leg and foot were absent. This was validated on prior electromyography and nerve conduction velocity testing, performed by a board certified neurologist. Patient was treated using spinal manipulation twice-weekly and wobble chair exercises three times daily for 90 days total. Following this treatment, the patient was referred for follow-up electrodiagnostic studies. Significant improvements were made in these studies as well as self-rated daily function. CONCLUSION: Motion-based therapies, as part of a comprehensive rehabilitation program, may contribute to the restoration of daily function and the reversal of neurological insult as detected by electrodiagnostic testing. Electrodiagnostic testing may be a useful clinical tool to evaluate the progress of chiropractic patients with lumbar disc herniation and radicular pain syndromes
Increased concentration of two different advanced glycation end-products detected by enzyme immunoassays with new monoclonal antibodies in sera of patients with rheumatoid arthritis
<p>Abstract</p> <p>Background</p> <p>Levels of pentosidine (representative of advanced glycation end-products) in sera of patients with rheumatoid arthritis are increased when compared with sera of other diagnoses or healthy controls. These levels have been reported to correlate with clinical indices of rheumatoid arthritis activity and with laboratory markers of inflammation. The purpose of this study was to find out if these findings pertain to other advanced glycation end-products.</p> <p>Methods</p> <p>We have developed two immunoassays based on new monoclonal antibodies to advanced glycation end-products. Antibody 103-E3 reacts with an unidentified antigen, formed in the reaction of proteins with ribose, while antibody 8-C1 responds to N<sup>ε</sup>-(carboxyethyl)lysine. We have used these monoclonal antibodies to measure levels of advanced glycation end-products in sera of patients with rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, and healthy controls. We calculated the correlations between advanced glycation end-product levels in rheumatoid arthritis sera and the Disease Activity Score 28 (DAS28), age, disease duration, CRP, anti-CCP, rheumatoid factor and treatment with corticosteroids, respectively.</p> <p>Results</p> <p>Levels of both glycation products were significantly higher in sera of patients with rheumatoid arthritis when compared with sera of patients with systemic lupus erythematosus, osteoarthritis, or the healthy controls. Neither the level of N<sup>ε</sup>-(carboxyethyl)lysine nor the level of the 103-E3 antigen in rheumatoid arthritis sera correlated with the DAS28-scored rheumatoid arthritis activity. The levels of both antigens in rheumatoid arthritis sera did not correlate with age, gender, corticosteroid treatment, or levels of CRP, anti-CCP antibodies, and rheumatoid factor in sera.</p> <p>Conclusions</p> <p>We report highly specific increases in the levels of two advanced glycation end-products in sera of patients with rheumatoid arthritis. This increase could be explained neither by rheumatoid arthritis activity nor by inflammation. We propose a working hypothesis that presumes the existence of a link between advanced glycation end-product formation and induction of autoimmunity.</p
Exploring Barriers and Opportunities in Adopting Crowdsourcing Based New Product Development in Manufacturing SMEs
Crowdsourcing is an innovative business practice of obtaining needed services, ideas, or content or even funds by soliciting contributions from a large group of people (the ‘Crowd’). The potential benefits of utilizing crowdsourcing in product design are well-documented, but little research exists on what are the barriers and opportunities in adopting crowdsourcing in new product development (NPD) of manufacturing SMEs. In order to answer the above questions, a Proof of Market study is carried out on crowdsourcing-based product design under an Innovate UK funded Smart project, which aims at identifying the needs, challenges and future development opportunities associated with adopting crowdsourcing strategies for NPD. The research findings from this study are reported here and can be used to guide future development of crowdsourcing-based collaborative design methods and tools and provide some practical references for industry to adopt this new and emerging collaborative design method in their business
Structural versus Electrical Functionalization of Oligo(phenyleneethynylene) Diamine Molecular Junctions
We explore both experimentally and theoretically the conductance and packing of molecular junctions based on oligo(phenyleneethynylene) (OPE) diamine wires, when a series of functional groups are incorporated into the wires. Using the scanning tunnelling microscopy break-junction (STM BJ) technique, we study these compounds in two environments (air and 1,2,4-trichlorobenzene) and explore different starting molecular concentrations. We show that the electrical conductance of the molecular junctions exhibits variations among different compounds, which are significant at standard concentrations but become unimportant when working at a low enough concentration. This shows that the main effect of the functional groups is to affect the packing of the molecular wires, rather than to modify their electrical properties. Our theoretical calculations consistently predict no significant changes in the conductance of the wires due to the electronic structure of the functional groups, although their ability to hinder ring rotations within the OPE backbone can lead to higher conductances at higher packing densities
Biomechanical considerations in the pathogenesis of osteoarthritis of the knee
Osteoarthritis is the most common joint disease and a major cause of disability. The knee is the large joint most affected. While chronological age is the single most important risk factor of osteoarthritis, the pathogenesis of knee osteoarthritis in the young patient is predominantly related to an unfavorable biomechanical environment at the joint. This results in mechanical demand that exceeds the ability of a joint to repair and maintain itself, predisposing the articular cartilage to premature degeneration. This review examines the available basic science, preclinical and clinical evidence regarding several such unfavorable biomechanical conditions about the knee: malalignment, loss of meniscal tissue, cartilage defects and joint instability or laxity
Glycation associated skin autofluorescence and skin elasticity are related to chronological age and body mass index of healthy subjects
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