Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Development ; 150(14)2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37366052

RESUMO

Gene ontology analyses of high-confidence autism spectrum disorder (ASD) risk genes highlight chromatin regulation and synaptic function as major contributors to pathobiology. Our recent functional work in vivo has additionally implicated tubulin biology and cellular proliferation. As many chromatin regulators, including the ASD risk genes ADNP and CHD3, are known to directly regulate both tubulins and histones, we studied the five chromatin regulators most strongly associated with ASD (ADNP, CHD8, CHD2, POGZ and KMT5B) specifically with respect to tubulin biology. We observe that all five localize to microtubules of the mitotic spindle in vitro in human cells and in vivo in Xenopus. Investigation of CHD2 provides evidence that mutations present in individuals with ASD cause a range of microtubule-related phenotypes, including disrupted localization of the protein at mitotic spindles, cell cycle stalling, DNA damage and cell death. Lastly, we observe that ASD genetic risk is significantly enriched among tubulin-associated proteins, suggesting broader relevance. Together, these results provide additional evidence that the role of tubulin biology and cellular proliferation in ASD warrants further investigation and highlight the pitfalls of relying solely on annotated gene functions in the search for pathological mechanisms.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno Autístico/genética , Transtorno Autístico/complicações , Transtorno Autístico/metabolismo , Cromatina/metabolismo , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Tubulina (Proteína)/metabolismo , Histonas/metabolismo , Microtúbulos/metabolismo , Fuso Acromático/metabolismo
2.
South Med J ; 115(7): 395-399, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35777742

RESUMO

OBJECTIVES: Although high-stakes interviews are critically important for residents to obtain competitive fellowships, few formalized programs targeting interviewing skills exist. Previous studies demonstrate that mock interviews increase medical students' and healthcare professionals' confidence and improve match rates, but little research has been conducted among medical residents. The objective of our study was to increase trainees' confidence entering fellowship interviews and prepare them for commonly encountered questions via a mock interview program. METHODS: Emory Internal Medicine residency leaders designed a voluntary mock interview program focused on 103 residents (64% of the overall cohort) pursuing fellowship training (median 36, range 30-37/year) from 2018 to 2020. Administrative staff scheduled eight associate program director interviewers for 75 hours of interviews for 3 years (mean 3.6 hours per interviewer per year), ensuring program feasibility. Interviewers underwent faculty development and used a standardized tool with commonly asked interview questions to conduct mock interviews. Interviewers provided feedback on verbal communication, nonverbal communication, professionalism, and, given recent shifts to virtual interviews, camera readiness. We conducted resident surveys to understand their perceptions of mock interview program experiences. RESULTS: Ninety-nine residents pursuing fellowship (96%) enrolled. Fifty (51%) completed the survey (median 20, range 14-22/year); 46 (92%) reported that the mock interviews were helpful or increased their confidence for interview season. CONCLUSIONS: Residents perceived that this high-fidelity mock interview program successfully prepared them at a critical career juncture. This program is feasible, sustainable, adaptable, and scalable, and may be adopted to benefit trainees in any graduate medical education program.


Assuntos
Bolsas de Estudo , Estudantes de Medicina , Educação de Pós-Graduação em Medicina , Retroalimentação , Humanos , Inquéritos e Questionários
5.
bioRxiv ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38854068

RESUMO

The comorbidity of autism spectrum disorders and severe gastrointestinal symptoms is well-established, yet the molecular underpinnings remain unknown. The identification of high-confidence large-effect autism risk genes offers the opportunity to identify convergent, underlying biology by studying these genes in the context of the gastrointestinal system. Here we show that the expression of these genes is enriched in human prenatal gut neurons as well as their migratory progenitors, suggesting that the development and/or function of these neurons may be disrupted by autism-associated pathogenic variants, leading to gastrointestinal dysfunction. Here we document the prevalence of gastrointestinal issues in patients with large-effect variants in sixteen of these genes, highlighting dysmotility, consistent with potential enteric neuron dysfunction. Using the high-throughput diploid frog Xenopus tropicalis , we individually target five of these genes ( SYNGAP1, CHD8, SCN2A, CHD2 , and DYRK1A ) and observe disrupted enteric neuronal progenitor migration for each. More extensive analysis of DYRK1A reveals that perturbation causes gut dysmotility in vivo , which can be ameliorated by treatment with a selective serotonin reuptake inhibitor (escitalopram) or a serotonin receptor 6 agonist, identified by in vivo drug screening. This work suggests that atypical development of enteric neurons contributes to the gastrointestinal distress commonly seen in individuals with autism and that increasing serotonin signaling may be a productive therapeutic avenue.

6.
J Immunother Cancer ; 12(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38642938

RESUMO

BACKGROUND: Colitis caused by checkpoint inhibitors (CPI) is frequent and is treated with empiric steroids, but CPI colitis mechanisms in steroid-experienced or refractory disease are unclear. METHODS: Using colon biopsies and blood from predominantly steroid-experienced CPI colitis patients, we performed multiplexed single-cell transcriptomics and proteomics to nominate contributing populations. RESULTS: CPI colitis biopsies showed enrichment of CD4+resident memory (RM) T cells in addition to CD8+ RM and cytotoxic CD8+ T cells. Matching T cell receptor (TCR) clonotypes suggested that both RMs are progenitors that yield cytotoxic effectors. Activated, CD38+ HLA-DR+ CD4+ RM and cytotoxic CD8+ T cells were enriched in steroid-experienced and a validation data set of steroid-naïve CPI colitis, underscoring their pathogenic potential across steroid exposure. Distinct from ulcerative colitis, CPI colitis exhibited perturbed stromal metabolism (NAD+, tryptophan) impacting epithelial survival and inflammation. Endothelial cells in CPI colitis after anti-TNF and anti-cytotoxic T-lymphocyte-associated antigen 4 (anti-CTLA-4) upregulated the integrin α4ß7 ligand molecular vascular addressin cell adhesion molecule 1 (MAdCAM-1), which may preferentially respond to vedolizumab (anti-α4ß7). CONCLUSIONS: These findings nominate CD4+ RM and MAdCAM-1+ endothelial cells for targeting in specific subsets of CPI colitis patients.


Assuntos
Linfócitos T CD8-Positivos , Colite , Humanos , Células Endoteliais , Inibidores do Fator de Necrose Tumoral , Colite/induzido quimicamente , Colite/tratamento farmacológico , Linfócitos T CD4-Positivos , Esteroides/farmacologia , Esteroides/uso terapêutico , Células Estromais
7.
J Grad Med Educ ; 15(5): 564-571, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37781425

RESUMO

Background The utility of traditional academic factors to predict residency candidates' performance is unclear. Many programs utilize holistic review processes assessing applicants on an expanded range of application and interview characteristics. Determining which characteristics might predict performance-related difficulty in residency is needed. Objective We aim to elucidate factors associated with residency performance-related difficulty in a large academic internal medicine residency program. Methods In 2022, we conducted a retrospective cohort study of Electronic Residency Application Service and interview data for residents matriculating between 2018 and 2020. The primary outcome was a composite of performance-related difficulty during residency (referral to the Clinical Competency Committee; any rotation evaluation score of 2 out of 5 or lower; and/or a confidential "comment of concern" to the program director). Logistic regression models were fit to assess associations between resident characteristics and the composite outcome. Results Thirty-eight of 117 residents met the composite outcome. Gold Humanism Honor Society (odds ratio [OR] 0.24, 95% confidence interval [CI] 0.16-0.87) or Alpha Omega Alpha (OR 0.36, 95% CI 0.14-0.99) members were less likely to have performance-related difficulty, as were residents with higher United States Medical Licensing Examination Step 2 Clinical Knowledge scores (OR 0.97, 95% CI 0.47-1.00). One-point increases in general faculty overall interview score, leadership competency score, and leadership overall score were associated with 41% to 63% lower odds of meeting the composite outcome. Interview or file review "flags" had an OR of 2.82 (95% CI 1.37-5.80) for the composite outcome. Conclusions Seven metrics were associated with the composite outcome of resident performance-related difficulty.


Assuntos
Internato e Residência , Humanos , Estados Unidos , Estudos Retrospectivos , Competência Clínica , Sociedades , Benchmarking
8.
Acad Med ; 97(7): 1021-1028, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35020617

RESUMO

PURPOSE: To characterize the existence, accessibility, and content of parental leave policies, as well as barriers to program-level policy implementation among internal medicine (IM) program directors (PDs) and to assess the willingness of PDs to implement a national standardized policy. METHOD: In 2019, the Association of Program Directors in Internal Medicine conducted a survey of 422 IM PDs. Along with other content, 38 questions addressed 4 primary outcomes: parental leave policy existence, accessibility, content, and barriers. The authors compared programs with and without a program-level policy and applied qualitative content analysis to open-ended questions about barriers to policy implementation and openness to a national standard. RESULTS: The response rate was 69.4% (293/422). Of responding programs, 86% (250/290) reported a written parental leave policy with 43% (97/225) of these originating at the program level. Program-level policies, compared with policies at other levels, were more likely to address scheduling during pregnancy (38%, 36/95 vs 22%, 27/124; P = .018); peer coverage (24%, 21/89 vs 15%, 16/109; P = .037), how the duration of extended training is determined (81%, 72/89 vs 44%, 48/109; P < .001), and associated pay and benefits 61%, 54/89 vs 44%, 48/109; P = .009). PDs without program-level policy reported lacking guidance to develop policy, deferring upward to institutional policies, and wishing to retain flexibility. More than half of PDs (60%, 170/282) expressed agreement that a national standard for a residency program-level parental leave policy should exist. Those not in favor cited organization equity, lack of resources, implementation challenges, loss of flexibility, and potentially disadvantaging recruitment. CONCLUSIONS: While existing program-level policies included important content, most PDs reported not having them. A national standard to guide the development of program-level parental leave policies could be embraced if it provided flexibility for programs with limited resources.


Assuntos
Internato e Residência , Feminino , Humanos , Medicina Interna , Política Organizacional , Licença Parental , Gravidez , Inquéritos e Questionários , Estados Unidos
9.
Acad Med ; 95(12S Addressing Harmful Bias and Eliminating Discrimination in Health Professions Learning Environments): S93-S97, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32889942

RESUMO

PROBLEM: Gender equity in leadership across academic medicine remains a concern. The case of chief resident (CR) offers an opportunity to explore novel strategies in leadership selection in graduate medical education (GME). Means of identifying potential candidates for CR often rely on faculty assessment of resident performance, yet implicit gender bias has the potential to influence this assessment. APPROACH: To diversify the metrics used in CR selection, an intervention was implemented to solicit resident input to identify candidates for CR at 2 U.S. internal medicine residency programs in 2018 and 2019. This involved a simple, cross-sectional survey of residents in which they were asked to identify individual residents as good candidates for consideration for CR. OUTCOMES: There were 298 of 518 internal medicine resident responses to this intervention across sites and years (mean 58.2% response rate). Nomination patterns of residents and program leaders correlated significantly (correlation coefficient 0.62, P < .001). Controlling for site and year, gender was a significant factor associated with who residents nominated for CR (ß-coefficient 0.325, P = .004) with women residents more likely to identify women for CR (odds ratio 1.38, 95% confidence interval 1.11-1.73). Fifty residents nominated themselves for CR, and there was no significant difference by gender (ß-coefficient 0.038, P = .91). NEXT STEPS: Soliciting resident input to identify candidates for CR may enable gender representation of candidates for this position. Influencing candidate choices may be a promising way to impact leadership selection in medicine.


Assuntos
Papel de Gênero , Internato e Residência/normas , Liderança , Médicos/psicologia , Adulto , Estudos Transversais , Educação de Pós-Graduação em Medicina/métodos , Feminino , Humanos , Internato e Residência/métodos , Internato e Residência/tendências , Masculino , Pessoa de Meia-Idade , Médicos/normas , Médicos/tendências , Estados Unidos
10.
mBio ; 11(3)2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546616

RESUMO

Staphylococcus aureus infection is a major public health threat in part due to the spread of antibiotic resistance and repeated failures to develop a protective vaccine. Infection is associated with production of virulence factors that include exotoxins that attack host barriers and cellular defenses, such as the leukocidin (Luk) family of bicomponent pore-forming toxins. To investigate the structural basis of antibody-mediated functional inactivation of Luk toxins, we generated a panel of murine monoclonal antibodies (MAbs) that neutralize host cell killing by the γ-hemolysin HlgCB. By biopanning these MAbs against a phage-display library of random Luk peptide fragments, we identified a small subregion within the rim domain of HlgC as the epitope for all the MAbs. Within the native holotoxin, this subregion folds into a conserved ß-hairpin structure, with exposed key residues, His252 and Tyr253, required for antibody binding. On the basis of the phage-display results and molecular modeling, a 15-amino-acid synthetic peptide representing the minimal epitope on HlgC (HlgC241-255) was designed, and preincubation with this peptide blocked antibody-mediated HIgCB neutralization. Immunization of mice with HlgC241-255 or the homologous LukS246-260 subregion peptide elicited serum antibodies that specifically recognized the native holotoxin subunits. Furthermore, serum IgG from patients who were convalescent for invasive S. aureus infection showed neutralization of HlgCB toxin activity ex vivo, which recognized the immunodominant HlgC241-255 peptide and was dependent on His252 and Tyr253 residues. We have thus validated an efficient, rapid, and scalable experimental workflow for identification of immunodominant and immunogenic leukotoxin-neutralizing B-cell epitopes that can be exploited for new S. aureus-protective vaccines and immunotherapies.


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Epitopos de Linfócito B/imunologia , Exotoxinas/imunologia , Proteínas Hemolisinas/imunologia , Epitopos Imunodominantes/imunologia , Animais , Anticorpos Antibacterianos/sangue , Mapeamento de Epitopos , Feminino , Humanos , Epitopos Imunodominantes/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Leucocidinas/química , Leucocidinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Biblioteca de Peptídeos , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/imunologia , Staphylococcus aureus , Fatores de Virulência
11.
Acad Med ; 95(10): 1550-1557, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32568852

RESUMO

PURPOSE: To characterize how female residents make decisions about childbearing, factors associated with the decision to delay childbearing, and satisfaction with these decisions. METHOD: In 2017, the authors sent a voluntary, anonymous survey to 1,537 female residents enrolled across 78 graduate medical education programs, consisting of 25 unique specialties, at 6 U.S. academic medical centers. Survey items included personal, partner, and institutional characteristics, whether the respondent was delaying childbearing during residency, and the respondent's satisfaction with this decision. RESULTS: The survey response rate was 52% (n = 804). Among the 447 (56%) respondents who were married or partnered, 274 (61%) were delaying childbearing. Residents delaying childbearing were significantly more likely to be younger (P < .001), not currently a parent (P < .001), in a specialty with an uncontrollable lifestyle (P = .001), or in a large program (P = .004). Among self-reported reasons for delaying childbearing, which were not mutually exclusive, the majority cited a busy work schedule (n = 255; 93%) and desire not to extend residency training (n = 145; 53%). Many cited lack of access to childcare (n = 126; 46%), financial concerns (n = 116; 42%), fear of burdening colleagues (n = 96; 35%), and concern for pregnancy complications (n = 74; 27%). Only 38% (n = 103) of respondents delaying childbearing were satisfied with this decision, with satisfaction decreasing with increasing age. CONCLUSIONS: Decisions to delay childbearing are more common in certain specialties, and many residents who delay childbearing are not satisfied with that decision. These findings suggest that greater attention is needed overall, and particularly in certain specialties, to promote policies and cultures that both anticipate and normalize parenthood in residency, thus minimizing the conflict between biological and professional choices for female residents.


Assuntos
Internato e Residência , Médicas/psicologia , Comportamento Reprodutivo/psicologia , Estudantes de Medicina/psicologia , Local de Trabalho/psicologia , Centros Médicos Acadêmicos , Adulto , Tomada de Decisões , Educação de Pós-Graduação em Medicina , Feminino , Humanos , Licença Parental , Gravidez , Inquéritos e Questionários , Tolerância ao Trabalho Programado
12.
Curr Treat Options Cardiovasc Med ; 21(9): 47, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31359165

RESUMO

PURPOSE OF REVIEW: Increased recognition of risk factors and improved knowledge of sex-specific presentations has led to improved clinical outcomes for women with cardiovascular disease (CVD) compared to two decades ago. Yet, CVD remains the leading cause of death for women in the USA. Women have unique risk factors for CVD that continue to go under-recognized by their physicians. RECENT FINDINGS: In a nationwide survey of primary care physicians (PCPs) and cardiologists, only 22% of PCPs and 42% of cardiologists reported being extremely well prepared to assess CVD risk in women. A presidential advisory from the American Heart Association (AHA) and American College of Obstetrics and Gynecologist (ACOG) recommends that cardiologists and obstetricians and gynecologists (Ob/Gyns) collaborate to promote CVD risk identification and reduction throughout a woman's lifetime. We suggest a comprehensive approach to identify unique and traditional risk factors for CVD in women, address the gap in physician knowledge, and improve cardiovascular care for women.

13.
BJR Case Rep ; 5(2): 20180113, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31501710

RESUMO

Takayasu arteritis (TA) is a systemic chronic inflammatory large-vessel vasculitis that affects the aorta, its major branches, and the pulmonary arteries. In this report, we describe a case of a young female with TA presenting with spontaneous subarachnoid hemorrhage (SAH), an unusual manifestation of the disease. Magnetic resonance angiography (MRA) of the head and neck demonstrates multifocal carotid and vertebral arterial stenoses, but no aneurysm or vascular malformation to account for SAH. A novel and unexpected finding in this case was increased cerebral perfusion in the right frontotemporal parenchyma and transient abnormally reduced augmentation of flow in response to the cerebral vasodilator acetazolamide. The etiology of SAH thus may be related to hyperperfusion and loss of cerebrovascular autoregulation leading to small vessel damage.

14.
Acad Med ; 94(11): 1738-1745, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31094723

RESUMO

PURPOSE: To characterize determinants of resident maternity leave and the effect of length of leave on maternal well-being. METHOD: In 2017, the authors sent a voluntary, anonymous survey to female residents at 78 programs, in 25 unique specialties, at 6 institutions. Survey items included personal, partner, and child demographics, and logistics of leave, including whether leave was paid or vacation or sick leave was used. Outcomes were maternity leave length; duration of breastfeeding; burnout and postpartum depression screens; perceptions of support; and satisfaction with length of leave, breastfeeding, and childbearing during residency. RESULTS: Fifty-two percent (804/1,537) of residents responded. Among 16% (126) of respondents who were mothers, 50% (63) had their first child during residency. Seventy-seven maternity leaves were reported (range, 2-40 weeks), with most taking 6 weeks (32% of leaves; 25) and including vacation (81%; 62) or sick leave (64%; 49). Length of leave was associated with institution, use of sick leave or vacation, and amount of paid leave. The most frequently self-reported determinant of leave was the desire not to extend residency training (27%; 59). Training was not extended for 53% (41) of mothers; 9% (7) were unsure. Longer breastfeeding duration and perceptions of logistical support from program administration were associated with longer maternity leaves. Burnout affected approximately 50% (38) of mothers regardless of leave length. CONCLUSIONS: This study illustrates variability in administration of resident maternity leaves. Targets for intervention include policy clarification, improving program support, and consideration of parent wellness upon return to work.


Assuntos
Educação de Pós-Graduação em Medicina/organização & administração , Promoção da Saúde/organização & administração , Internato e Residência/organização & administração , Mães/estatística & dados numéricos , Política Organizacional , Licença Parental/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos , Adulto , Feminino , Humanos , Autorrelato , Estados Unidos
15.
Acad Med ; 94(10): 1581-1588, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31192796

RESUMO

PURPOSE: To explore faculty perspectives on which characteristics of high-performing clerkship students are most important when determining an honors or top grade designation for clinical performance. METHOD: In 2016-2017, the authors surveyed faculty (teaching ward attendings) for internal medicine clerkships and 1 pediatrics clerkship in inpatient settings at 5 U.S. academic medical centers. Survey items were framed around competencies, 24 student characteristics, and attitudes toward evaluation. Factor analysis examined constructs defining high-performing students. RESULTS: Of 516 faculty invited, 319 (62%) responded. The top 5 characteristics as rated by respondents were taking ownership, clinical reasoning, curiosity, dependability, and high ethical standards (in descending order). Twenty-one characteristics fit into 3 factors (Cronbach alpha, 0.81-0.87). Clinical reasoning did not fit into a factor. Factor 1 was the most important (mean rating, 8.7/10 [95% confidence interval (CI), 8.6-8.8]). It included professionalism components (ownership, curiosity, dependability, high ethical standards), presentation and interviewing skills, seeking feedback, and documentation. Factor 2 (mean, 7.9 [95% CI, 7.7-8.0]) included aspects of teamwork and communication, such as positive attitude and comments from others. Factor 3 (mean, 7.6 [95% CI, 7.4-7.7]) addressed systems-based thinking, including patient safety and care transitions. CONCLUSIONS: Professionalism components, clinical reasoning, and curiosity were among the most important characteristics distinguishing high-performing clerkship students. These may represent behaviors that are highly valued, observable, and relevant to training stage. Improved definition of the characteristics associated with clinical honors would assist students, faculty, and residency program directors when interpreting clinical performance within core clerkships.


Assuntos
Distinções e Prêmios , Estágio Clínico , Competência Clínica , Comportamento Exploratório , Docentes de Medicina , Profissionalismo , Centros Médicos Acadêmicos , Humanos , Medicina Interna/educação , Pediatria/educação , Inquéritos e Questionários
16.
Arthritis Care Res (Hoboken) ; 68(12): 1866-1873, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27696755

RESUMO

OBJECTIVE: The Rheumatology Informatics System for Effectiveness (RISE) is a national electronic health record (EHR)-enabled registry. RISE passively collects data from EHRs of participating practices, provides advanced quality measurement and data analytic capacities, and fulfills national quality reporting requirements. Here we report the registry's architecture and initial data, and we demonstrate how RISE is being used to improve the quality of care. METHODS: RISE is a certified Centers for Medicare and Medicaid Services Qualified Clinical Data Registry, allowing collection of data without individual patient informed consent. We analyzed data between October 1, 2014 and September 30, 2015 to characterize initial practices and patients captured in RISE. We also analyzed medication use among rheumatoid arthritis (RA) patients and performance on several quality measures. RESULTS: Across 55 sites, 312 clinicians contributed data to RISE; 72% were in group practice, 21% in solo practice, and 7% were part of a larger health system. Sites contributed data on 239,302 individuals. Among the subset with RA, 34.4% of patients were taking a biologic or targeted synthetic disease-modifying antirheumatic drug (DMARD) at their last encounter, and 66.7% were receiving a nonbiologic DMARD. Examples of quality measures include that 55.2% had a disease activity score recorded, 53.6% a functional status score, and 91.0% were taking a DMARD in the last year. CONCLUSION: RISE provides critical infrastructure for improving the quality of care in rheumatology and is a unique data source to generate new knowledge. Data validation and mapping are ongoing and RISE is available to the research and clinical communities to advance rheumatology.


Assuntos
Aplicações da Informática Médica , Melhoria de Qualidade , Qualidade da Assistência à Saúde/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Reumatologia/normas , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Humanos , Masculino , Medicaid/estatística & dados numéricos , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Estados Unidos
17.
Biosens Bioelectron ; 20(10): 1914-24, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15741058

RESUMO

This report describes the development of novel sonochemically fabricated, bioengineered acetylcholinesterase and polyaniline carbon/cobalt phthalocyanine biosensors for the ultra-sensitive determination of a number of different pesticides. Arrays of this type typically have population micro-electrode densities of up to approximately 2 x 10(5) cm(-2); these represent the highest micro-electrode population densities reported to date by any fabrication means. The enzymatic response of the sensors is inhibited upon incubation with the pesticide, and we have shown that Dichlorvos, Parathion and Azinphos may be determined down to concentrations of approximately 1 x 10(-17) M, approximately 1 x 10(-16) M and approximately 1 x 10(-16) M, respectively. These lower limits of detection are lower than otherwise achievable by any other analytical approach. Measurements were performed within a custom built flow injection system that operates at a constant flow of 1 ml min(-1). Sensor stability studies were also performed whereby a stabilizer mixture of sucrose and polygalacturonic acid was added to the immobilised enzyme matrix at the working electrode and left to dry. Sixty-five percent of the initial enzyme activity was found to remain after a period of 92 days to allow storage of these electrodes and facilitating transportation if required.


Assuntos
Acetilcolinesterase/química , Técnicas Biossensoriais/instrumentação , Análise de Injeção de Fluxo/instrumentação , Microeletrodos , Organofosfatos/análise , Praguicidas/química , Poluentes Químicos da Água/análise , Acetilcolinesterase/análise , Técnicas Biossensoriais/métodos , Materiais Revestidos Biocompatíveis/análise , Materiais Revestidos Biocompatíveis/química , Eletroquímica/instrumentação , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Injeção de Fluxo/métodos , Organofosfatos/química , Praguicidas/análise , Sonicação
18.
Biosens Bioelectron ; 20(4): 765-72, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15522591

RESUMO

This paper describes the development of a novel sonochemically fabricated microelectrode based acetylcholinesterase and polyaniline carbon/cobalt phthalocyanine biosensor for the ultra-sensitive determination of pesticides. Arrays of this type are fabricated using microelectrode templates with population densities of 2 x 10(5) cm(-2). The enzymatic response of the sensors is inhibited upon incubation with the pesticide and in this report it is shown that paraoxon may be determined down to concentrations of 1 x 10(-17) M. This sensitivity has thus far not been achieved and mechanisms accounting for the enhancement of the sensitivity reported here are discussed.


Assuntos
Acetilcolinesterase/química , Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Monitoramento Ambiental/instrumentação , Microeletrodos , Paraoxon/análise , Praguicidas/análise , Acetilcolina/análise , Técnicas Biossensoriais/métodos , Materiais Revestidos Biocompatíveis/química , Eletroquímica/métodos , Monitoramento Ambiental/métodos , Enzimas Imobilizadas/química , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sonicação/instrumentação
19.
Biosens Bioelectron ; 18(5-6): 579-85, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12706565

RESUMO

This paper describes the development of a novel optically interrogated enzyme electrode with generic applicability for NAD(P) dependent enzymes. The example reported here employs a multi-enzyme pathway comprising the enzymes pyruvate kinase, hexokinase, glucose-6-phosphate dehydrogenase and diaphorase. The final substrate of this pathway, dichlorophenol indophenol (DCPIP), was immobilised within an ultra-thin polymer film of o-phenylenediamine, itself electrochemically polymerised onto a conductive gold coating on the surface of a support polyethylene sheet. Dichlorophenol indophenol (DCPIP) absorbs within the visible region of the spectrum with a lambda(max) approximately 600 nm. When reduced, the molar absorption coefficient at this wavelength decreases significantly and DCPIP effectively becomes colourless (DCPIPH(3)). Ultra-thin layers of gold (<10 nm thickness) exhibit an optical absorption minimum at wavelengths of approximately 520 nm and therefore light within this region of the spectrum may be transmitted with relative ease through the polymer/gold/polyethylene optrode. Results presented within this paper show how this electro-optical sensor may be used to determine concentrations of adenosine triphosphate (ATP) within a sample. In the presence of ATP a colour change from blue to colourless was observed for DCPIP when the assay was performed in solution. However, when DCPIP was immobilised within a polymeric film onto the surface of gold coated electrodes, a colour change from blue to red was observed corresponding to a third redox state of DCPIP (DCPIPH).


Assuntos
2,6-Dicloroindofenol/química , Trifosfato de Adenosina/análise , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Eletroquímica/instrumentação , NADP/química , Óptica e Fotônica/instrumentação , Trifosfato de Adenosina/química , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Biosens Bioelectron ; 20(2): 328-37, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15308238

RESUMO

A novel and patented procedure is described for the sonochemical fabrication of a new class of microelectrode array based sensor with electrode element populations of up to 2 x 10(5) cm(-2). For some years it has been accepted that microelectrode arrays offer an attractive route for lowering minimum limits of detection and imparting stir (convectional mass transport) independence to sensor responses; despite this no commercial biosensors, to date, have employed microelectrode arrays, largely due to the cost of conventional fabrication routes that have not proved commercially viable for disposable devices. Biosensors formed by our sonochemical approach offer unrivalled sensitivity and impart stir independence to sensor responses. This format lends itself for mass fabrication due to the simplicity and inexpensiveness of the approach; in the first instance impedimetric and amperometric sensors are reported for glucose as model systems. Sensors already developed for ethanol, oxalate and a number of pesticide determinations will be reported in subsequent publications.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Glucose Oxidase/química , Glucose/análise , Glucose/química , Microeletrodos , Sonicação , Técnicas Biossensoriais/métodos , Materiais Revestidos Biocompatíveis/química , Eletroquímica/métodos , Enzimas Imobilizadas/análise , Enzimas Imobilizadas/química , Desenho de Equipamento , Análise de Falha de Equipamento , Glucose Oxidase/análise , Manufaturas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA