Enhancement of the Antibacterial Properties of Silver Nanoparticles Using Beta-Cyclodextrin as a Capping Agent

Silver nanoparticles (AgNPs) were synthesized by reducing silver salts using NaBH4 followed by capping with varying concentrations of β-cyclodextrin (β-CD) and were physically characterised. Antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was determined by a microtitre well method. The AgNPs were spherical under TEM while DLS showed average diameters of capped particles to be smaller (4-7 nm) than their uncapped equivalents (17 nm). Capped particles demonstrated superior photostability when exposed to intense UV radiation for 4 hours and a significantly (

Silver Doped Perfluoropolyether-Urethane Coatings: Antibacterial Activity and Surface Analysis

The colonisation of clinical and industrial surfaces with pathogenic microorganisms has prompted increased research into the development of effective antibacterial and antifouling coatings. There is evidence that implanted biomedical surfaces coated with metallic silver can be inactivated by hysiological fluids, thus reducing the bioactivity of the coating. In this work, we report the biofilm inhibition of Staphylococcus epidermidis using a roomtemperatureprocessedsilver dopedperfluoropolyether-urethane coating. The release of silver ions from these fluoropolymers over a six-day period inhibited bacterial encrustation – as observed by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) analysis indicated differences in carbon, fluorine and sodium surface composition between silver doped and undoped fluoropolymers after exposure to nutrient rich media. These silver doped perfluoropolyether coatings also exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii; suggesting potential use in preventing transmission of pathogenic and opportunistic microbes on environmental surfaces in healthcare facilities. The broad-spectrum antibacterial activity of these silver release coatings may be exploited on biomaterials surfaces to combat the development of resistant Gram-negative Enterobacteriaceae that can occur during prophylactic treatment for urinary tract infections

Protective Properties of Functionalised Tetrazine on an Aerospace Aluminium Alloy (AA 2024-T3)

Environmental health concerns over conventional chromium based surface treatments on aluminium substrates are well known. Current research efforts have concentrated on developing protective technologies for multiple applications. Such properties would enable manufacturers to address both corrosion and bacterial threats in areas such as fuel tanks and delivery systems. The present study explores the anticorrosion properties of 1,2-dihydro 1, 2, 4, 5 tetrazine-3, 6-dicarboxylic acid (H2DCTZ) on a copper rich aerospace aluminium alloy (AA 2024-T3). Furthermore the antimicrobial activity of the tetrazine is evaluated against Gram-positive and Gram-negative bacteria, both capable of inducing corrosion. The protective action of the tetrazine was investigated at different concentrations in a chloride ion rich environment (3.5% (w/v) NaCl) utilising electrochemical impedance spectroscopy (EIS). Results over a 72 h period proved that an optimum concentration was 500 ppm. FTIR and SEM elemental mapping of the surface confirmed the nitrogen rich tetrazine affinity for the copper rich intermetallic sites, through coordinate bonds, which delayed corrosion onset and reduced pit formation. Moderate antibacterial tetrazine activity was observed against Escherichia coli and 100% efficacy against Staphylococcus aureus at 250 ppm was achieved. The damage of the bacterial cell envelope at the critical concentrations (250 ppm) is proposed as a possible mechanism for antibacterial action

Clinicopathological evaluation of chronic traumatic encephalopathy in players of American football

IMPORTANCE: Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). OBJECTIVE: To determine the neuropathological and clinical features of deceased football players with CTE. DESIGN, SETTING, AND PARTICIPANTS: Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. EXPOSURES: Participation in American football at any level of play. MAIN OUTCOMES AND MEASURES: Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. RESULTS: Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre–high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89%) had behavioral or mood symptoms or both, 80 (95%) had cognitive symptoms, and 71 (85%) had signs of dementia. CONCLUSIONS AND RELEVANCE: In a convenience sample of deceased football players who donated their brains for research, a high proportion had neuropathological evidence of CTE, suggesting that CTE may be related to prior participation in football.This study received support from NINDS (grants U01 NS086659, R01 NS078337, R56 NS078337, U01 NS093334, and F32 NS096803), the National Institute on Aging (grants K23 AG046377, P30AG13846 and supplement 0572063345-5, R01 AG1649), the US Department of Defense (grant W81XWH-13-2-0064), the US Department of Veterans Affairs (I01 CX001038), the Veterans Affairs Biorepository (CSP 501), the Veterans Affairs Rehabilitation Research and Development Traumatic Brain Injury Center of Excellence (grant B6796-C), the Department of Defense Peer Reviewed Alzheimer’s Research Program (grant 13267017), the National Operating Committee on Standards for Athletic Equipment, the Alzheimer’s Association (grants NIRG-15-362697 and NIRG-305779), the Concussion Legacy Foundation, the Andlinger Family Foundation, the WWE, and the NFL

Research priorities relating to the delivery of cardiovascular prevention and rehabilitation programmes: results of a modified Delphi process

Objective: The purpose of this British Association for Cardiovascular Prevention and Rehabilitation (BACPR) research priority setting project (PSP) was to identify a top 10 list of priority research questions for cardiovascular prevention and rehabilitation (CVPR). Methods: The PSP was facilitated by the BACPR clinical study group (CSG), which integrates as part of the British Heart Foundation Clinical Research Collaborative. Following a literature review to identify unanswered research questions, modified Delphi methods were used to engage CVPR-informed expert stakeholders, patients, partners and conference delegates in ranking the relevance of research questions during three rounds of an anonymous e-survey. In the first survey, unanswered questions from the literature review were ranked and respondents proposed additional questions. In the second survey, these new questions were ranked. Prioritised questions from surveys 1 and 2 were incorporated in a third/final e-survey used to identify the top 10 list. Results: From 459 responses across the global CVPR community, a final top 10 list of questions were distilled from an overall bank of 76 (61 from the current evidence base and a further 15 from respondents). These were grouped across five broad categories: access and remote delivery, exercise and physical activity, optimising programme outcomes, psychosocial health and impact of the pandemic. Conclusions: This PSP used a modified Delphi methodology to engage the international CVPR community to generate a top 10 list of research priorities within the field. These prioritised questions will directly inform future national and international CVPR research supported by the BACPR CSG

FLT3 mutation incidence and timing of origin in a population case series of pediatric leukemia

<p>Abstract</p> <p>Background</p> <p>Mutations in <it>FLT3 </it>result in activated tyrosine kinase activity, cell growth stimulation, and a poor prognosis among various subtypes of leukemia. The causes and timing of the mutations are not currently known. We evaluated the prevalence and timing of origin of <it>FLT3 </it>mutations in a population series of childhood leukemia patients from Northern California.</p> <p>Methods</p> <p>We screened and sequenced <it>FLT3 </it>mutations (point mutations and internal tandem duplications, ITDs) among 517 childhood leukemia patients, and assessed whether these mutations occurred before or after birth using sensitive "backtracking" methods.</p> <p>Results</p> <p>We determined a mutation prevalence of 9 of 73 acute myeloid leukemias (AMLs, 12%) and 9 of 441 acute lymphocytic leukemias (ALLs, 2%). Among AMLs, <it>FLT3 </it>mutations were more common in older patients, and among ALLs, <it>FLT3 </it>mutations were more common in patients with high hyperdiploidy (3.7%) than those without this cytogenetic feature (1.4%). Five <it>FLT3 </it>ITDs, one deletion mutation, and 3 point mutations were assessed for their presence in neonatal Guthrie spots using sensitive real-time PCR techniques, and no patients were found to harbor <it>FLT3 </it>mutations at birth.</p> <p>Conclusions</p> <p><it>FLT3 </it>mutations were not common in our population-based patient series in California, and patients who harbor <it>FLT3 </it>mutations most likely acquire them after they are born.</p

Improved monitoring of clinical response in Systemic Lupus Erythematosus by longitudinal trend in soluble vascular cell adhesion molecule-1

This work was funded by Arthritis Research UK. MJL holds an Arthritis Research UK Clinician Scientist Fellowship (19631), and was previously supported by the St Thomas’ Lupus Trust. The study received support from the National Institute for Health Research (NIHR)-funded Flow Cytometry Core Facility and the Biomedical Research Centre based at Guy’s & St. Thomas’ National Health Service (NHS) Foundation Trust, in partnership with King’s College London

Nanosecond laser textured superhydrophobic metallic surfaces and their chemical sensing applications

tThis work demonstrates superhydrophobic behavior on nanosecond laser patterned copper and brasssurfaces. Compared with ultrafast laser systems previously used for such texturing, infrared nanosecondfiber lasers offer a lower cost and more robust system combined with potentially much higher processingrates. The wettability of the textured surfaces develops from hydrophilicity to superhydrophobicity overtime when exposed to ambient conditions. The change in the wetting property is attributed to the par-tial deoxidation of oxides on the surface induced during laser texturing. Textures exhibiting steady statecontact angles of up to ∼152◦with contact angle hysteresis of around 3–4◦have been achieved. Inter-estingly, the superhydrobobic surfaces have the self-cleaning ability and have potential for chemicalsensing applications. The principle of these novel chemical sensors is based on the change in contactangle with the concentration of methanol in a solution. To demonstrate the principle of operation ofsuch a sensor, it is found that the contact angle of methanol solution on the superhydrophobic surfacesexponentially decays with increasing concentration. A significant reduction, of 128◦, in contact angle onsuperhydrophobic brass is observed, which is one order of magnitude greater than that for the untreatedsurface (12◦), when percent composition of methanol reaches to 28%