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OBJECTIVES: To quantify reader agreement for the British Society of Thoracic Imaging (BSTI) diagnostic and severity classification for COVID-19 on chest radiographs (CXR), in particular agreement for an indeterminate CXR that could instigate CT imaging, from single and paired images. METHODS: Twenty readers (four groups of five individuals)-consultant chest (CCR), general consultant (GCR), and specialist registrar (RSR) radiologists, and infectious diseases clinicians (IDR)-assigned BSTI categories and severity in addition to modified Covid-Radiographic Assessment of Lung Edema Score (Covid-RALES), to 305 CXRs (129 paired; 2 time points) from 176 guideline-defined COVID-19 patients. Percentage agreement with a consensus of two chest radiologists was calculated for (1) categorisation to those needing CT (indeterminate) versus those that did not (classic/probable, non-COVID-19); (2) severity; and (3) severity change on paired CXRs using the two scoring systems. RESULTS: Agreement with consensus for the indeterminate category was low across all groups (28-37%). Agreement for other BSTI categories was highest for classic/probable for the other three reader groups (66-76%) compared to GCR (49%). Agreement for normal was similar across all radiologists (54-61%) but lower for IDR (31%). Agreement for a severe CXR was lower for GCR (65%), compared to the other three reader groups (84-95%). For all groups, agreement for changes across paired CXRs was modest. CONCLUSION: Agreement for the indeterminate BSTI COVID-19 CXR category is low, and generally moderate for the other BSTI categories and for severity change, suggesting that the test, rather than readers, is limited in utility for both deciding disposition and serial monitoring. KEY POINTS: ⢠Across different reader groups, agreement for COVID-19 diagnostic categorisation on CXR varies widely. ⢠Agreement varies to a degree that may render CXR alone ineffective for triage, especially for indeterminate cases. ⢠Agreement for serial CXR change is moderate, limiting utility in guiding management.
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COVID-19 , Humanos , Radiografia Torácica/métodos , Reprodutibilidade dos Testes , Radiografia , Radiologistas , Estudos RetrospectivosRESUMO
The posterior tibial tendon is a gliding tendon which courses around the medial malleolus and fails in posterior tibialis tendon dysfunction (PTTD) leading to a flat foot deformity. Distal tibial bone spurs have been identified as a secondary sign of PTTD although they have not been quantified in detail. The aim of this study was to assess the association of tendon dysfunction with the bony morphology of the tibial retro-malleolar groove. We performed a retrospective review of the clinical presentation, plain radiographs, and 103 magnetic resonance imaging (MRI) scans in 82 consecutive patients with PTTD compared with a non-PTTD group. We carried out a quantitative and qualitative assessment of the presence of plain radiographic bone spurs, stage of PTTD and MRI imaging of the morphology of the tibial bony malleolar groove. Plain radiographic bone spurs, as a secondary sign of PTTD, were present in 21.3% of ankle radiographs. MRI bone spurs were identified in 26/41 (63.4%) for all high-grade partial and complete tears and 7/41 (17.1%) for isolated complete tears compared with only 3.9% of the non-PTTD group. There was a significant association between the presence of bone spurs on MRI imaging and high-grade partial and complete tibialis posterior tears (p < .001; odds ratio of 4.98). Eleven of 103 (10.7%) of spurs were large and in 4/103 (3.9%) were substantial enough to create a tunnel-like hypertrophic groove not previously reported. There is variation in the bony structure of the malleolar groove in PTTD not observed in the non-PTTD group. Further investigation over time may elucidate whether the groove morphology may lead to mechanical attrition of the tibialis posterior tendon and contribute to failure of healing and progressive tendon degeneration.
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Exostose , Pé Chato , Osteófito , Disfunção do Tendão Tibial Posterior , Humanos , Osteófito/complicações , Osteófito/patologia , Disfunção do Tendão Tibial Posterior/diagnóstico por imagem , Disfunção do Tendão Tibial Posterior/complicações , Pé , Tendões/patologia , Pé Chato/diagnóstico , Exostose/complicaçõesRESUMO
In this Account, we detail recent progress in wearable bioelectronic devices and discuss the future challenges and prospects of on-body noninvasive bioelectronic systems. Bioelectronics is a fast-growing interdisciplinary research field that involves interfacing biomaterials with electronics, covering an array of biodevices, encompassing biofuel cells, biosensors, ingestibles, and implantables. In particular, enzyme-based bioelectronics, built on diverse biocatalytic reactions, offers distinct advantages and represents a centerpiece of wearable biodevices. Such wearable bioelectronic devices predominately rely on oxidoreductase enzymes and have already demonstrated considerable promise for on-body applications ranging from highly selective noninvasive biomarker monitoring to epidermal energy harvesting. These systems can thus greatly increase the analytical capability of wearable devices from the ubiquitous monitoring of mobility and vital signs, toward the noninvasive analysis of important chemical biomarkers. Wearable enzyme electrodes offer exciting opportunities to a variety of areas, spanning from healthcare, sport, to the environment or defense. These include real-time noninvasive detection of biomarkers in biofluids (such as sweat, saliva, interstitial fluid and tears), and the monitoring of environmental pollutants and security threats in the immediate surrounding of the wearer. Furthermore, the interface of enzymes with conducting flexible electrode materials can be exploited for developing biofuel cells, which rely on the bioelectrocatalytic oxidation of biological fuels, such as lactate or glucose, for energy harvesting applications. Crucial for such successful application of enzymatic bioelectronics is deep knowledge of enzyme electron-transfer kinetics, enzyme stability, and enzyme immobilization strategies. Such understanding is critical for establishing efficient electrical contacting between the redox enzymes and the conducting electrode supports, which is of fundamental interest for the development of robust and efficient bioelectronic platforms. Furthermore, stretchable and flexible bioelectronic platforms, with mechanical properties similar to those of biological tissues, are essential for handling the rigors of on-body operation. As such, special attention must be given to changes in the behavior of enzymes due to the uncontrolled conditions of on-body operation (including diverse outdoor activities and different biofluids), for maintaining the attractive performance that these bioelectronics devices display in controlled laboratory settings. Therefore, a focus of this Account is on interfacing biocatalytic layers onto wearable electronic devices for creating efficient and stable on-body electrochemical biosensors and biofuel cells. With proper attention to key challenges and by leveraging the advantages of biocatalysis, electrochemistry, and flexible electronics, wearable bioelectronic devices could have a tremendous impact on diverse biomedical, fitness, and defense fields.
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Técnicas Biossensoriais/métodos , Enzimas/metabolismo , Dispositivos Eletrônicos Vestíveis , Biomarcadores/análise , Técnicas Biossensoriais/instrumentação , Líquidos Corporais/metabolismo , Telefone Celular , Poluentes Ambientais/análise , Enzimas/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Humanos , Oxirredutases/química , Oxirredutases/metabolismoRESUMO
Antibacterial polymers are potentially powerful biocides that can destroy bacteria on contact. Debate in the literature has surrounded the mechanism of action of polymeric biocides and the propensity for bacteria to develop resistance to them. There has been particular interest in whether surfaces with covalently coupled polymeric biocides have the same mechanism of action and resistance profile as similar soluble polymeric biocides. We designed and synthesized a series of poly(quaternary ammonium) polymers, with tailorable molecular structures and architectures, to engineer their antibacterial specificity and their ability to delay the development of bacterial resistance. These linear poly(quaternary ammonium) homopolymers and block copolymers, generated using atom transfer radical polymerization, had structure-dependent antibacterial specificity toward Gram positive and negative bacterial species. When single block copolymers contained two polymer segments of differing antibacterial specificity, the polymer combined the specificities of its two components. Nanoparticulate human serum albumin-poly(quaternary ammonium) conjugates of these same polymers, synthesized via "grafting from" atom transfer radical polymerization, were strongly biocidal and also exhibited a marked decrease in the rate of bacterial resistance development relative to linear polymers. These protein-biocide conjugates mimicked the behavior of surface-presented polycationic biocides rather than their nonproteinaceous counterparts.
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Antibacterianos , Bactérias/crescimento & desenvolvimento , Polímeros , Compostos de Amônio Quaternário , Albumina Sérica Humana , Adsorção , Antibacterianos/química , Antibacterianos/farmacologia , Células HEK293 , Humanos , Polímeros/química , Polímeros/farmacologia , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Albumina Sérica Humana/química , Albumina Sérica Humana/farmacologiaRESUMO
The reduced immunogenicity and increased stability of protein-polymer conjugates has made their use in therapeutic applications particularly attractive. However, the physicochemical interactions between polymer and protein, as well as the effect of this interaction on protein activity and stability, are still not fully understood. In this work, polymer-based protein engineering was used to examine the role of polymer physicochemical properties on the activity and stability of the chymotrypsin-polymer conjugates and their degree of binding to intestinal mucin. Four different chymotrypsin-polymer conjugates, each with the same polymer density, were synthesized using "grafting-from" atom transfer radical polymerization. The influence of polymer charge on chymotrypsin-polymer conjugate mucin binding, bioactivity, and stability in stomach acid was determined. Cationic polymers covalently attached to chymotrypsin showed high mucin binding, while zwitterionic, uncharged, and anionic polymers showed no mucin binding. Cationic polymers also increased chymotrypsin activity from pH 6-8, while zwitterionic polymers had no effect, and uncharged and anionic polymers decreased enzyme activity. Lastly, cationic polymers decreased the tendency of chymotrypsin to structurally unfold at extremely low pH, while uncharged and anionic polymers induced unfolding more quickly. We hypothesized that when polymers are covalently attached to the surface of a protein, the degree to which those polymers interact with the protein surface is the predominant determinant of whether the polymer will stabilize or inactivate the protein. Preferential interactions between the polymer and the protein lead to removal of water from the surface of the protein, and this, we believe, inactivates the enzyme.
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Quimotripsina/metabolismo , Ácido Gástrico/química , Mucinas/metabolismo , Polímeros/metabolismo , Adesão Celular , Quimotripsina/química , Humanos , Mucinas/química , Polimerização , Polímeros/química , Ligação Proteica , Engenharia de ProteínasRESUMO
Purpose Grade ≥3 adverse effects prolong hospitalization and reduce chemotherapy dose intensity. The purpose of this study was to evaluate the rate and severity of high-dose methotrexate-related acute kidney injury and analyze its effect on hospital length of stay and relative chemotherapy dose intensity. Methods This was a retrospective cohort analysis. Patients receiving ≥1 dose of high-dose methotrexate were analyzed for acute kidney injury and length of stay. Patients receiving ≥6 cycles of induction therapy were included in the analysis of relative chemotherapy dose intensity. Chi squared analysis was used to determine the differences between dichotomous data; Student's t-test for parametric data and Mann-Whitney U test for non-parametric data for continuous variables. Statistical analyses were performed with IBM SPSS Statistics (version 21). Results Twenty-six patients and 194 treatment encounters were identified. Thirteen patients were evaluated for relative chemotherapy dose intensity. Grade ≥3 acute kidney injury occurred in four patients (15% of patients; 2% of encounters). There were no grade 5 adverse events. Mean length of stay for encounters with grade ≥3 acute kidney injury was almost three times longer than for those with ≤ grade 2 acute kidney injury (p = 0.041). Mean relative chemotherapy dose intensity was reduced approximately in half for patients experiencing grade ≥3 acute kidney injury (p < 0.01). The most common adverse events were hypokalemia and nausea. Proton pump inhibitors were the most frequently co-administered medications with the potential to affect high-dose methotrexate pharmacokinetics. Conclusion At our cancer program, the rate of grade ≥3 acute kidney injury with high-dose methotrexate is similar to that reported by others. Grade ≥3 acute kidney injury following high-dose methotrexate administration significantly prolonged length of stay and reduced relative chemotherapy dose intensity.
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Injúria Renal Aguda/induzido quimicamente , Linfoma/tratamento farmacológico , Metotrexato/administração & dosagem , Idoso , Estudos de Coortes , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
INTRODUCTION: A non-contrast CT head scan (NCCTH) is the most common cross-sectional imaging investigation requested in the emergency department. Advances in computer vision have led to development of several artificial intelligence (AI) tools to detect abnormalities on NCCTH. These tools are intended to provide clinical decision support for clinicians, rather than stand-alone diagnostic devices. However, validation studies mostly compare AI performance against radiologists, and there is relative paucity of evidence on the impact of AI assistance on other healthcare staff who review NCCTH in their daily clinical practice. METHODS AND ANALYSIS: A retrospective data set of 150 NCCTH will be compiled, to include 60 control cases and 90 cases with intracranial haemorrhage, hypodensities suggestive of infarct, midline shift, mass effect or skull fracture. The intracranial haemorrhage cases will be subclassified into extradural, subdural, subarachnoid, intraparenchymal and intraventricular. 30 readers will be recruited across four National Health Service (NHS) trusts including 10 general radiologists, 15 emergency medicine clinicians and 5 CT radiographers of varying experience. Readers will interpret each scan first without, then with, the assistance of the qER EU 2.0 AI tool, with an intervening 2-week washout period. Using a panel of neuroradiologists as ground truth, the stand-alone performance of qER will be assessed, and its impact on the readers' performance will be analysed as change in accuracy (area under the curve), median review time per scan and self-reported diagnostic confidence. Subgroup analyses will be performed by reader professional group, reader seniority, pathological finding, and neuroradiologist-rated difficulty. ETHICS AND DISSEMINATION: The study has been approved by the UK Healthcare Research Authority (IRAS 310995, approved 13 December 2022). The use of anonymised retrospective NCCTH has been authorised by Oxford University Hospitals. The results will be presented at relevant conferences and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT06018545.
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Inteligência Artificial , Medicina Estatal , Humanos , Estudos Retrospectivos , Hemorragias Intracranianas/diagnóstico por imagem , Pessoal Técnico de SaúdeRESUMO
PURPOSE: Hydration and urinary alkalinization are essential for reducing renal dysfunction with high dose methotrexate (HDMTX). This report presents an analysis of institutional methods used to achieve adequate urinary alkalinization and output for patients receiving single agent HDMTX. Renal and metabolic parameters of tolerance were examined. METHODS: Medical records of adult patients receiving HDMTX during the calendar years of 2008-2009 were retrospectively reviewed to determine the time to achieve urine pH > 7. Number of hospital days, bicarbonate dose, ordered hydration rate, urine output, and urine pH were assessed. A survival analysis model was run for time to urine pH > 7 using preadmission oral bicarbonate as a predictor variable and including a frailty term. Observational statistics were performed for other parameters. RESULTS: The analysis included 79 encounters for ten patients. Urine pH > 7 was achieved more rapidly in patients receiving preadmission oral bicarbonate (P = 0.012). The number of patients receiving HDMTX on the same day as admission was greater for those receiving preadmission oral bicarbonate (47%) in comparison to those who did not (2%), and they spent less time in the hospital. A standard regimen for hydration and urinary alkalinization based on this project is reported. The nature and frequency of adverse events were as expected for this treatment. CONCLUSION: At our institution, the time to achieve urinary alkalinization was reduced for patients receiving preadmission oral bicarbonate which facilitated chemotherapy infusion on the same day as admission and decreased the number of calendar days that patients stayed in the hospital.
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Injúria Renal Aguda/urina , Bicarbonatos/administração & dosagem , Tempo de Internação/tendências , Metotrexato/administração & dosagem , Metotrexato/urina , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Administração Oral , Idoso , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/tendências , Feminino , Humanos , Masculino , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Urinálise/métodosRESUMO
BACKGROUND: Male infertility is a common cause of reproductive failure in humans. In mice, targeted deletions of the genes coding for FKBP6 or FKBP52, members of the FK506 binding protein family, can result in male infertility. In the case of FKBP52, this reflects an important role in potentiating Androgen Receptor (AR) signalling in the prostate and accessory glands, but not the testis. In infertile men, no mutations of FKBP52 or FKBP6 have been found so far, but the gene for FKBP-like (FKBPL) maps to chromosome 6p21.3, an area linked to azoospermia in a group of Japanese patients. METHODS: To determine whether mutations in FKBPL could contribute to the azoospermic phenotype, we examined expression in mouse and human tissues by RNA array blot, RT-PCR and immunohistochemistry and sequenced the complete gene from two azoospermic patient cohorts and matching control groups. FKBPL-AR interaction was assayed using reporter constructs in vitro. RESULTS: FKBPL is strongly expressed in mouse testis, with expression upregulated at puberty. The protein is expressed in human testis in a pattern similar to FKBP52 and also enhanced AR transcriptional activity in reporter assays. We examined sixty patients from the Japanese patient group and found one inactivating mutation and one coding change, as well as a number of non-coding changes, all absent in fifty-six controls. A second, Irish patient cohort of thirty showed another two coding changes not present in thirty proven fertile controls. CONCLUSIONS: Our results describe the first alterations in the gene for FKBPL in azoospermic patients and indicate a potential role in AR-mediated signalling in the testis.
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Imunofilinas/genética , Infertilidade Masculina/genética , Sequência de Aminoácidos , Animais , Estudos de Casos e Controles , Estudos de Coortes , Ligação Genética , Predisposição Genética para Doença , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Mutação/fisiologia , Homologia de Sequência de Aminoácidos , Proteínas de Ligação a Tacrolimo , Análise Serial de TecidosRESUMO
Tumour responses to radiotherapy are currently primarily assessed by changes in size. Imaging permits non-invasive, whole-body assessment of tumour burden and guides treatment options for most tumours. However, in most tumours, changes in size are slow to manifest and can sometimes be difficult to interpret or misleading, potentially leading to prolonged durations of ineffective treatment and delays in changing therapy. Functional imaging techniques that monitor biological processes have the potential to detect tumour responses to treatment earlier and refine treatment options based on tumour biology rather than solely on size and staging. By considering the biological effects of radiotherapy, this review focusses on emerging functional imaging techniques with the potential to augment morphological imaging and serve as biomarkers of early response to radiotherapy.
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Wearable biosensors are garnering substantial interest due to their potential to provide continuous, real-time physiological information via dynamic, noninvasive measurements of biochemical markers in biofluids, such as sweat, tears, saliva and interstitial fluid. Recent developments have focused on electrochemical and optical biosensors, together with advances in the noninvasive monitoring of biomarkers including metabolites, bacteria and hormones. A combination of multiplexed biosensing, microfluidic sampling and transport systems have been integrated, miniaturized and combined with flexible materials for improved wearability and ease of operation. Although wearable biosensors hold promise, a better understanding of the correlations between analyte concentrations in the blood and noninvasive biofluids is needed to improve reliability. An expanded set of on-body bioaffinity assays and more sensing strategies are needed to make more biomarkers accessible to monitoring. Large-cohort validation studies of wearable biosensor performance will be needed to underpin clinical acceptance. Accurate and reliable real-time sensing of physiological information using wearable biosensor technologies would have a broad impact on our daily lives.
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Técnicas Biossensoriais/instrumentação , Monitorização Fisiológica/instrumentação , Dispositivos Eletrônicos Vestíveis , Técnicas Biossensoriais/tendências , Biotecnologia , Líquidos Corporais/química , Sistemas Computacionais , Humanos , Iontoforese/instrumentação , Dispositivos Lab-On-A-Chip , Monitorização Fisiológica/tendências , Saliva/química , Suor/química , Lágrimas/química , Dispositivos Eletrônicos Vestíveis/tendênciasRESUMO
We report on a wearable tear bioelectronic platform, integrating a microfluidic electrochemical detector into an eyeglasses nose-bridge pad, for non-invasive monitoring of key tear biomarkers. The alcohol-oxidase (AOx) biosensing fluidic system allowed real-time tear collection and direct alcohol measurements in stimulated tears, leading to the first wearable platform for tear alcohol monitoring. Placed outside the eye region this fully wearable tear-sensing platform addresses drawbacks of sensor systems involving direct contact with the eye as the contact lenses platform. Integrating the wireless electronic circuitry into the eyeglasses frame thus yielded a fully portable, convenient-to-use fashionable sensing device. The tear alcohol sensing concept was demonstrated for monitoring of alcohol intake in human subjects over multiple drinking courses, displaying good correlation to parallel BAC measurements. We also demonstrate for the first time the ability to monitor tear glucose outside the eye and the utility of wearable devices for monitoring vitamin nutrients in connection to enzymatic flow detector and rapid voltammetric scanning, respectively. These developments pave the way to build an effective eyeglasses system capable of chemical tear analysis.
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Técnicas Biossensoriais , Óculos , Monitorização Fisiológica , Lágrimas/química , Álcoois/química , Álcoois/isolamento & purificação , Glucose/química , Glucose/isolamento & purificação , Humanos , Vitaminas/química , Vitaminas/isolamento & purificação , Dispositivos Eletrônicos VestíveisRESUMO
The rapid development of wearable sensing platforms in recent years has led to an array of viable monitoring applications for various target analytes. As a significant biomarker with high impact in diverse areas, the reliable on-body detection and continuous monitoring of alcohol has become a focus of many such systems. Currently, several commercial sensing platforms are available that are capable of transdermal monitoring of alcohol consumption using insensible sweat. Drawbacks of existing alcohol sensing platforms that apply this sensing strategy have led to efforts in developing wearable biosensors capable of real-time alcohol detection in sampled biofluids such as sensible sweat and skin interstitial fluid. This review discusses the current trends in wearable electrochemical alcohol biosensing and highlights recent advances in such systems toward continuous, real-time monitoring of alcohol consumption. Our perspective on this important field is given with an outlook on the future of wearable electrochemical alcohol biosensors.
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The growing recent interest in wearable and mobile technologies has led to increased research efforts toward development of non-invasive glucose monitoring platforms. Continuous glucose monitoring addresses the limitations of finger-stick blood testing and provides the opportunity for optimal therapeutic interventions. This article reviews recent advances and challenges toward the development of non-invasive epidermal electrochemical glucose sensing systems. Recent reports claim success in glucose monitoring in human subjects using skin-worn electrochemical sensors. Such epidermal electrochemical biosensors obviate the disadvantages of minimally-invasive subcutaneous glucose biosensors and offer promise for improved glycemic control. The ability of such systems to monitor glucose non-invasively offers an attractive route toward advancing the management of diabetes and achieving improved glycemic control. However, realizing the potential diagnostic impact of these new epidermal sensing strategies would require extensive efforts toward addressing key technological challenges and establishing a reliable correlation to gold standard blood glucose meters.
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Automonitorização da Glicemia/instrumentação , Epiderme/química , Dispositivos Eletrônicos Vestíveis , Eletroquímica , HumanosRESUMO
OBJECTIVE: While many people with Type 1 diabetes find it difficult to achieve recommended blood glucose levels, a minority do achieve good control. Our study was conceived by patient and public (PP) partners and sought to learn about experiences of people living with well-controlled diabetes. DESIGN: A collaboration between academic health psychologists and five PP partners with experience of diabetes, who were trained to conduct and analyse semi-structured interviews. Fifteen adults with well-controlled Type 1 diabetes were interviewed about the history of their diabetes and their current self-management practices. Interviews were subjected to inductive thematic analysis. RESULTS: Eight sub-themes were arranged into two overarching themes, 'facing up to diabetes' and 'balance leads to freedom'. Participants described a process of acceptance and mastery of diabetes, and talked about how they gained a deeper understanding of bodily processes through trial and error. CONCLUSION: Based on the experiences of people with well-controlled Type 1 diabetes, interventions for people with this condition should encourage acceptance of the diagnosis and increasing confidence to experiment with behaviours (trial and error) to encourage 'mastery' of self-management. The research collaboration described here is an example of best practice for future researchers wanting to actively engage PP partners.
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Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 1/terapia , Autocuidado/psicologia , Adaptação Psicológica , Adulto , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Masculino , Pesquisa QualitativaRESUMO
The development of wearable biosensors for continuous noninvasive monitoring of target biomarkers is limited to assays of a single sampled biofluid. An example of simultaneous noninvasive sampling and analysis of two different biofluids using a single wearable epidermal platform is demonstrated here. The concept is successfully realized through sweat stimulation (via transdermal pilocarpine delivery) at an anode, alongside extraction of interstitial fluid (ISF) at a cathode. The system thus allows on-demand, controlled sampling of the two epidermal biofluids at the same time, at two physically separate locations (on the same flexible platform) containing different electrochemical biosensors for monitoring the corresponding biomarkers. Such a dual biofluid sampling and analysis concept is implemented using a cost-effective screen-printing technique with body-compliant temporary tattoo materials and conformal wireless readout circuits to enable real-time measurement of biomarkers in the sampled epidermal biofluids. The performance of the developed wearable device is demonstrated by measuring sweat-alcohol and ISF-glucose in human subjects consuming food and alcoholic drinks. The different compositions of sweat and ISF with good correlations of their chemical constituents to their blood levels make the developed platform extremely attractive for enhancing the power and scope of next-generation noninvasive epidermal biosensing systems.
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BACKGROUND: To investigate the presence of pathogenic microbes on chiropractic treatment tables in one outpatient teaching clinic. Additional aims were to test inexpensive disinfectants on tables that may kill microbes and suggest infection control measures for chiropractic offices, clinics and classrooms. The aim of the study was to assess the presence of pathogenic microbes on treatment tables in one outpatient teaching clinic and determine a simple behavioral model for infection control including table disinfection and accepted hand washing and sanitizing protocols. METHODS: 10 treatment tables were selected and sampled for possible microbial flora on face and hand pieces. Samples were cultured on MacConky's agar and mannitol salt agar, labeled and incubated for up to 48 hours. Confirmatory testing of microbes to determine if drug resistant flora were present was performed. Among tables tested, 5 were selected to test disinfectants. One-half of the face piece and 1 hand piece were treated with two different wipes and then post-tested for microbes. RESULTS: Pathogenic microbes were present on chiropractic treatment tables including methicillin-resistant Staph aureus. Simple disinfectants neutralized the pathogens. A rudimentary disinfection procedure and infection control measures are suggested based on the findings. CONCLUSION: Pathogenic microbes may be present on chiropractic treatment tables and can be effectively killed with proper disinfecting. Hand washing/sanitizing is an important measure in infection control as is table disinfecting. Rudimentary behavioral changes to improve chiropractic clinic infection control are needed. More comprehensive behavioral models are needed. All teaching clinics and private chiropractic offices should adopt infection control practices including routine table disinfecting and hand sanitizing. Effective measures can be put in place at minimal costs. Accrediting bodies of chiropractic institutions should mandate an infection control plan for member institutions immediately.
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This work describes a wireless wearable ring-based multiplexed chemical sensor platform for rapid electrochemical monitoring of explosive and nerve-agent threats in vapor and liquid phases. The ring-based sensor system consists of two parts: a set of printed electrochemical sensors and a miniaturized electronic interface, based on a battery-powered stamp-size potentiostat, for signal processing and wireless transmission of data. A wide range of electrochemical capabilities have thus been fully integrated into a 3D printed compact ring structure, toward performing fast square-wave voltammetry and chronoamperometric analyses, along with interchangeable screen-printed sensing electrodes for the rapid detection of different chemical threats. High analytical performance is demonstrated despite the remarkable miniaturization and integration of the ring system. The attractive capabilities of the wearable sensor ring system have been demonstrated for sensitive and rapid voltammetric and amperometric monitoring of nitroaromatic and peroxide explosives, respectively, along with amperometric biosensing of organophosphate (OP) nerve agents. Such ability of the miniaturized wearable sensor ring platform to simultaneously detect multiple chemical threats in both liquid and vapor phases and alert the wearer of such hazards offers considerable promise for meeting the demands of diverse defense and security scenarios.
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Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Substâncias para a Guerra Química/análise , Substâncias Explosivas/análise , Joias , Humanos , Tecnologia sem FioRESUMO
Despite tremendous recent efforts, noninvasive sweat monitoring is still far from delivering its early analytical promise. Here, we describe a flexible epidermal microfluidic detection platform fabricated through hybridization of lithographic and screen-printed technologies, for efficient and fast sweat sampling and continuous, real-time electrochemical monitoring of glucose and lactate levels. This soft, skin-mounted device judiciously merges lab-on-a-chip and electrochemical detection technologies, integrated with a miniaturized flexible electronic board for real-time wireless data transmission to a mobile device. Modeling of the device design and sweat flow conditions allowed optimization of the sampling process and the microchannel layout for achieving attractive fluid dynamics and rapid filling of the detection reservoir (within 8 min from starting exercise). The wearable microdevice thus enabled efficient natural sweat pumping to the electrochemical detection chamber containing the enzyme-modified electrode transducers. The fabricated device can be easily mounted on the epidermis without hindrance to the wearer and displays resiliency against continuous mechanical deformation expected from such epidermal wear. Amperometric biosensing of lactate and glucose from the rapidly generated sweat, using the corresponding immobilized oxidase enzymes, was wirelessly monitored during cycling activity of different healthy subjects. This ability to monitor sweat glucose levels introduces new possibilities for effective diabetes management, while similar lactate monitoring paves the way for new wearable fitness applications. The new epidermal microfluidic electrochemical detection strategy represents an attractive alternative to recently reported colorimetric sweat-monitoring methods, and hence holds considerable promise for practical fitness or health monitoring applications.
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Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Glucose/análise , Ácido Láctico/análise , Técnicas Analíticas Microfluídicas/instrumentação , Suor/química , Técnicas Biossensoriais/métodos , Dimetilpolisiloxanos/química , Técnicas Eletroquímicas/métodos , Enzimas Imobilizadas/química , Epiderme/metabolismo , Glucose Oxidase/química , Humanos , Dispositivos Lab-On-A-Chip , Limite de Detecção , Técnicas Analíticas Microfluídicas/métodos , Oxigenases de Função Mista/química , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodosRESUMO
The importance of early access to prehospital care has been demonstrated in many medical emergencies. This work aims to describe the potential time benefit of implementing a student Community First Responder scheme to support ambulance services in an inner-city setting in the United Kingdom. Twenty final and penultimate year medical students in the UK were trained in the "First Person on Scene" Business and Technology Education Council (BTEC) qualification. Over 12 months, they attended 89 emergency calls in an inner-city setting as Community First Responders (CFRs), alongside the West Midlands Ambulance Service, UK. At the end of this period, a qualitative survey investigated the perceived educational value of the scheme. The mean CFR response time across all calls was an average of 3 minutes and 8 seconds less than ambulance crew response times. The largest difference was to calls relating to falls (12 min). The difference varied throughout the day, peaking between 16:00 and 18:00. All questionnaire respondents stated that they felt more prepared in assessing and treating acutely unwell patients. In this paper, the authors present a symbiotic solution which has both reduced time to first on scene and provided training and experience in medical emergencies for senior medical students.