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1.
BMJ Open ; 14(3): e065498, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38458795

RESUMEN

OBJECTIVES: Given the increasing prevalence of obesity and need for effective interventions, there is a growing interest in understanding how an individual's body image can inform obesity prevention and management. This study's objective was to examine the use of silhouette showcards to measure body size perception compared with measured body mass index, and assess body size dissatisfaction, in three different African-origin populations spanning the epidemiological transition. An ancillary objective was to investigate associations between body size perception and dissatisfaction with diabetes and hypertension. SETTING: Research visits were completed in local research clinics in respective countries. PARTICIPANTS: Seven hundred and fifty-one African-origin participants from the USA and the Republic of Seychelles (both high-income countries), and Ghana (low/middle-income country). PRIMARY AND SECONDARY OUTCOME MEASURES: Silhouette showcards were used to measure perceived body size and body size dissatisfaction. Objectively measured body size was measured using a scale and stadiometer. Diabetes was defined as fasting blood glucose ≥126 mg/dL and hypertension was defined as ≥130 mm Hg/80 mm Hg. RESULTS: Most women and men from the USA and Seychelles had 'Perceived minus Actual weight status Discrepancy' scores less than 0, meaning they underestimated their actual body size. Similarly, most overweight or obese men and women also underestimated their body size, while normal weight men and women were accurately able to estimate their body size. Finally, participants with diabetes were able to accurately estimate their body size and similarly desired a smaller body size. CONCLUSIONS: This study highlights that overweight and obese women and men from countries spanning the epidemiological transition were unable to accurately perceive their actual body size. Understanding people's perception of their body size is critical to implementing successful obesity prevention programmes across the epidemiological transition.


Asunto(s)
Diabetes Mellitus , Hipertensión , Masculino , Humanos , Femenino , Sobrepeso/epidemiología , Sobrepeso/complicaciones , Imagen Corporal , Estudios de Cohortes , Obesidad/complicaciones , Índice de Masa Corporal , Hipertensión/epidemiología , Hipertensión/complicaciones , Peso Corporal
2.
J Fam Pract ; 72(8): 342-344, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37862621

RESUMEN

This study suggests the blood pressure-lowering effects of potassium-enriched salt substitutes may reduce cardiovascular morbidity and mortality.


Asunto(s)
Hipertensión , Humanos , Hipertensión/prevención & control , Presión Sanguínea
3.
JAMA Netw Open ; 6(10): e2336483, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37782499

RESUMEN

Importance: Natural language processing tools, such as ChatGPT (generative pretrained transformer, hereafter referred to as chatbot), have the potential to radically enhance the accessibility of medical information for health professionals and patients. Assessing the safety and efficacy of these tools in answering physician-generated questions is critical to determining their suitability in clinical settings, facilitating complex decision-making, and optimizing health care efficiency. Objective: To assess the accuracy and comprehensiveness of chatbot-generated responses to physician-developed medical queries, highlighting the reliability and limitations of artificial intelligence-generated medical information. Design, Setting, and Participants: Thirty-three physicians across 17 specialties generated 284 medical questions that they subjectively classified as easy, medium, or hard with either binary (yes or no) or descriptive answers. The physicians then graded the chatbot-generated answers to these questions for accuracy (6-point Likert scale with 1 being completely incorrect and 6 being completely correct) and completeness (3-point Likert scale, with 1 being incomplete and 3 being complete plus additional context). Scores were summarized with descriptive statistics and compared using the Mann-Whitney U test or the Kruskal-Wallis test. The study (including data analysis) was conducted from January to May 2023. Main Outcomes and Measures: Accuracy, completeness, and consistency over time and between 2 different versions (GPT-3.5 and GPT-4) of chatbot-generated medical responses. Results: Across all questions (n = 284) generated by 33 physicians (31 faculty members and 2 recent graduates from residency or fellowship programs) across 17 specialties, the median accuracy score was 5.5 (IQR, 4.0-6.0) (between almost completely and complete correct) with a mean (SD) score of 4.8 (1.6) (between mostly and almost completely correct). The median completeness score was 3.0 (IQR, 2.0-3.0) (complete and comprehensive) with a mean (SD) score of 2.5 (0.7). For questions rated easy, medium, and hard, the median accuracy scores were 6.0 (IQR, 5.0-6.0), 5.5 (IQR, 5.0-6.0), and 5.0 (IQR, 4.0-6.0), respectively (mean [SD] scores were 5.0 [1.5], 4.7 [1.7], and 4.6 [1.6], respectively; P = .05). Accuracy scores for binary and descriptive questions were similar (median score, 6.0 [IQR, 4.0-6.0] vs 5.0 [IQR, 3.4-6.0]; mean [SD] score, 4.9 [1.6] vs 4.7 [1.6]; P = .07). Of 36 questions with scores of 1.0 to 2.0, 34 were requeried or regraded 8 to 17 days later with substantial improvement (median score 2.0 [IQR, 1.0-3.0] vs 4.0 [IQR, 2.0-5.3]; P < .01). A subset of questions, regardless of initial scores (version 3.5), were regenerated and rescored using version 4 with improvement (mean accuracy [SD] score, 5.2 [1.5] vs 5.7 [0.8]; median score, 6.0 [IQR, 5.0-6.0] for original and 6.0 [IQR, 6.0-6.0] for rescored; P = .002). Conclusions and Relevance: In this cross-sectional study, chatbot generated largely accurate information to diverse medical queries as judged by academic physician specialists with improvement over time, although it had important limitations. Further research and model development are needed to correct inaccuracies and for validation.


Asunto(s)
Inteligencia Artificial , Médicos , Humanos , Estudios Transversales , Reproducibilidad de los Resultados , Programas Informáticos
4.
Res Sq ; 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36909565

RESUMEN

Background: Natural language processing models such as ChatGPT can generate text-based content and are poised to become a major information source in medicine and beyond. The accuracy and completeness of ChatGPT for medical queries is not known. Methods: Thirty-three physicians across 17 specialties generated 284 medical questions that they subjectively classified as easy, medium, or hard with either binary (yes/no) or descriptive answers. The physicians then graded ChatGPT-generated answers to these questions for accuracy (6-point Likert scale; range 1 - completely incorrect to 6 - completely correct) and completeness (3-point Likert scale; range 1 - incomplete to 3 - complete plus additional context). Scores were summarized with descriptive statistics and compared using Mann-Whitney U or Kruskal-Wallis testing. Results: Across all questions (n=284), median accuracy score was 5.5 (between almost completely and completely correct) with mean score of 4.8 (between mostly and almost completely correct). Median completeness score was 3 (complete and comprehensive) with mean score of 2.5. For questions rated easy, medium, and hard, median accuracy scores were 6, 5.5, and 5 (mean 5.0, 4.7, and 4.6; p=0.05). Accuracy scores for binary and descriptive questions were similar (median 6 vs. 5; mean 4.9 vs. 4.7; p=0.07). Of 36 questions with scores of 1-2, 34 were re-queried/re-graded 8-17 days later with substantial improvement (median 2 vs. 4; p<0.01). Conclusions: ChatGPT generated largely accurate information to diverse medical queries as judged by academic physician specialists although with important limitations. Further research and model development are needed to correct inaccuracies and for validation.

5.
Med J (Ft Sam Houst Tex) ; (Per 22-07/08/09): 38-42, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35951230

RESUMEN

The principle of medical triage, where patients are sorted into categories to guide the order in which they receive treatment, dates back to Baron Dominique Jean Larrey, the surgeon general of Napolean's armies. The concept evolved with military conflicts throughout the 19th century, was subsequently adapted to situations off the battlefield, and is now widely practiced where resources are limited.2 Military medical providers are taught triage principles early in their careers and its use is routinely integrated into military training scenarios and operational planning.


Asunto(s)
Medicina Militar , Triaje , Predicción , Humanos , Medicina Militar/historia , Pandemias , Asignación de Recursos
6.
Clin Transl Sci ; 15(4): 859-865, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35118815

RESUMEN

TPMT and NUDT15 variants explain less than 25% of azathioprine-associated myelotoxicity. There are 25 additional genes in the thiopurine pathway that could also contribute to azathioprine myelotoxicity. We hypothesized that among TPMT and NUDT15 normal metabolizers, a score combining the genetically predicted expression of other proteins in the thiopurine pathway would be associated with a higher risk for azathioprine discontinuation due to myelotoxicity. We conducted a retrospective cohort study of new users of azathioprine who were normal TPMT and NUDT15 metabolizers. In 1201 White patients receiving azathioprine for an inflammatory disease, we used relaxed Least Absolute Shrinkage and Selection Operator (LASSO) regression to select genes that built a score for discontinuing azathioprine due to myelotoxicity. The score incorporated the predicted expression of AOX1 and NME1. Patients in the highest score tertile had a higher risk of discontinuing azathioprine compared to those in the lowest tertile (hazard ratio [HR] = 2.15, 95% confidence interval [CI] = 1.11-4.19, p = 0.024). Results remained significant after adjusting for a propensity score, including sex, tertile of calendar year at initial dose, initial dose, age at baseline, indication, prior TPMT testing, and the first 10 principal components of the genetic data (HR = 2.11, 95% CI = 1.08-4.13, p = 0.030). We validated the results in a cohort (N = 517 non-White patients and those receiving azathioprine to prevent transplant rejection) that included all other patients receiving azathioprine (HR = 2.00, (95% CI = 1.09-3.65, p = 0.024). In conclusion, among patients who were TPMT and NUDT15 normal metabolizers, a score combining the predicted expression of AOX1 and NME1 was associated with an increased risk for discontinuing azathioprine due to myelotoxicity.


Asunto(s)
Azatioprina , Pirofosfatasas , Azatioprina/efectos adversos , Humanos , Redes y Vías Metabólicas/genética , Metiltransferasas/genética , Pirofosfatasas/genética , Estudios Retrospectivos
7.
PLOS Glob Public Health ; 2(5): e0000127, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36962336

RESUMEN

The Pulvers' silhouette showcards provide a non-invasive and easy-to-use way of assessing an individual's body size perception using nine silhouette shapes. However, their utility across different populations has not been examined. This study aimed to assess: 1) the relationship between silhouette perception and measured anthropometrics, i.e., body mass index (BMI), waist circumference (WC), waist-height-ratio (WHtR), and 2) the ability to predict with silhouette showcards anthropometric adiposity measures, i.e., overweight and obesity (BMI ≥ 25 kg/m2), obesity alone (BMI ≥ 30 kg/m2), elevated WC (men ≥ 94 cm; women ≥ 80 cm), and WHtR (> 0.5) across the epidemiological transition. 751 African-origin participants, aged 20-68 years old, from the United States (US), Seychelles, and Ghana, completed anthropometrics and selected silhouettes corresponding to their perceived body size. Silhouette performance to anthropometrics was examined using a least-squares linear regression model. A receiver operator curve (ROC) was used to investigate the showcards ability to predict anthropometric adiposity measures. The relationship between silhouette ranking and BMI were similar between sexes of the same country but differed between countries: 3.65 [95% CI: 3.34-3.97] BMI units/silhouette unit in the US, 3.23 [2.93-3.74] in Seychelles, and 1.99 [1.72-2.26] in Ghana. Different silhouette cutoffs predicted obesity differently in the three countries. For example, a silhouette ≥ five had a sensitivity/specificity of 77.3%/90.6% to predict BMI ≥ 25 kg/m2 in the US, but 77.8%/85.9% in Seychelles and 84.9%/71.4% in Ghana. Ultimately, silhouettes predicted BMI, WC, and WHtR similarly within each country and sex but not across countries. Our data suggest that Pulvers' silhouette showcards may be a helpful tool to predict anthropometric and adiposity measures in different populations when direct measurement cannot be performed. However, no universal silhouette cutoff can be used for detecting overweight or obesity status, and population-specific differences may stress the need to calibrate silhouette showcards when using them as a survey tool in different countries.

8.
Clin Pharmacol Ther ; 111(1): 263-271, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34582038

RESUMEN

Azathioprine is used frequently to treat several inflammatory conditions. However, treatment is limited by adverse events-in particular, myelotoxicity. Thiopurine-S-methyltransferase (TPMT) and nudix hydrolase-15 (NUDT15) are enzymes involved in azathioprine metabolism; variants in the genes encoding these enzymes increase the risk for azathioprine myelotoxicity. The Clinical Pharmacogenetics Implementation Consortium (CPIC) has recommended dose adjustments based on the results of TPMT and NUDT15 genotyping. However, little is known about the importance of this genetic information in routine clinical care. We hypothesized that in patients with inflammatory diseases, TPMT and NUDT15 genotype data predict the risk of discontinuing azathioprine due to myelotoxicity. This was a retrospective cohort study in 1,403 new adult azathioprine users for the management of inflammatory conditions for whom we had genetic information and clinical data. Among patients who discontinued azathioprine, we adjudicated the reason(s). Genotyping was performed using the Illumina Infinium Expanded Multi-Ethnic Genotyping Array plus custom content. We used CPIC guidelines to determine TPMT and NUDT15 metabolizer status; patients were grouped as either: (i) poor/intermediate, or (ii) normal/indeterminate metabolizers. We classified 110 patients as poor/intermediate, and 1,293 patients as normal/indeterminate metabolizers. Poor/intermediate status was associated with a higher risk for azathioprine discontinuation due to myelotoxicity compared to normal/indeterminate metabolizers (hazard ratio (HR) = 2.90, 95% confidence interval (CI): 1.58-5.31, P = 0.001). This association remained significant after adjustment for race, age at initiation, sex, primary indication, and initial daily dose of azathioprine (adjusted HR (aHR) = 2.67, 95% CI: 1.44-4.94, P = 0.002). In conclusion, TPMT and NUDT15 metabolizer status predicts discontinuation due to myelotoxicity for patients taking azathioprine for inflammatory conditions.


Asunto(s)
Antiinflamatorios/efectos adversos , Azatioprina/efectos adversos , Enfermedades de la Médula Ósea/inducido químicamente , Inflamación/tratamiento farmacológico , Metiltransferasas/genética , Variantes Farmacogenómicas/efectos de los fármacos , Pirofosfatasas/genética , Adulto , Antiinflamatorios/farmacocinética , Azatioprina/farmacocinética , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Farmacogenética/métodos , Polimorfismo Genético , Probabilidad , Estudios Retrospectivos
9.
Mil Med ; 187(3-4): 73-76, 2022 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-34476471

RESUMEN

As the COVID-19 pandemic continues across the globe, the advent of novel vaccines has created a possible path to prepandemic life for many. Still, many individuals, including those in the U.S. military, remain hesitant about getting vaccinated. The U.S. Food and Drug Administration recently granted full approval to the Pfizer-BioNTech mRNA vaccine (Comirnaty). Consistent with messaging from President Biden, the Department of Defense leadership has instructed the military to prepare for mandatory vaccination. While many have praised this declaration, others have raised concerns regarding the suppression of individual service member autonomy. This commentary explains the different ethical principles relevant to individual autonomy and how they are understood in a military context and then explores the ethical arguments both for and against mandating vaccination for all U.S. service members.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Humanos , Pandemias/prevención & control , Vacunas Sintéticas , Vacunas de ARNm
10.
Mil Med ; 186(Suppl 1): 762-766, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33499502

RESUMEN

INTRODUCTION: There is increasing interest in assessing gender and race-based disparities in academic medicine and healthcare leadership in civilian medicine and the U.S. Military Health System. Approximately 15% of U.S. active duty service members are women, and racial minorities are 30% of the total active duty force. This study evaluates the following factors among uniformed services family physicians: gender and race representation in attaining early career leadership positions during training and 2 years postresidency; perceptions regarding leadership opportunities and career advancement. METHODS: Registered attendees (n = 300) of the 2016 Uniformed Services Academy of Family Physicians Annual Meeting were given a voluntary and anonymous online questionnaire. The main outcomes measured were early leadership assignments and perceptions about command/leadership support, gender roles in leadership assignment, confidence to achieve leadership goals, and being passed over for leadership positions. RESULTS: Sixty-eight percent of registered attendees completed the study questionnaire. Statistically significant results, adjusting for service, grade, race, and gender, were that non-Caucasian family physicians were less likely to be chief residents (odds ratio 0.23, 95% CI 0.01-1.00) and less likely to have leadership positions within 2 years postresidency (odds ratio 0.30, 95% CI 0.10-0.91). Female family physicians were more likely to agree that gender has a role in assigning leadership positions (odds ratio 2.33, 95% CI 1.01-5.39). There were no differences in perceptions of command support for leadership; confidence in achieving desired leadership level; or in being passed over for leadership positions. CONCLUSIONS: This study provides important information about perceived gender and race equality among uniformed services family physicians. Key findings included that non-Caucasian military family physicians were less likely to attain junior leadership positions or be assigned to academic settings; and female respondents were more likely to agree that gender has a role in assignment of leadership positions. Evaluating composite personnel records of services' family physicians would provide invaluable information to complement this study.


Asunto(s)
Personal Militar , Femenino , Humanos , Liderazgo , Percepción , Médicos de Familia , Médicos Mujeres
11.
Pediatrics ; 146(Suppl 1): S13-S17, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32737227

RESUMEN

Although parents are typically the most appropriate decision-makers for their children, there are limits to this authority. Medical providers may be ethically obligated to seek state intervention against a parental decision if the parent places a child at significant and imminent risk of serious harm. When parents make medical decisions for their children, they assess both the projected benefits and risks of their choices for their family. These assessments are impacted by uncertainty, which is a common feature of neonatal intensive care. The relative presence or absence of uncertainty may impact perceptions of parental decisions and a medical provider's decision to seek state intervention to overrule parents. In this article, we propose a model integrating prognostic uncertainty into pediatric decision-making that may aid providers in such assessments. We will demonstrate how to apply this model to 3 neonatal cases and propose that the presence of greater uncertainty ought to permit parents greater latitude to incorporate family values into their decision-making even if these decisions are contradictory to the recommendations of the medical team.


Asunto(s)
Discusiones Bioéticas , Toma de Decisiones Clínicas/ética , Padres , Incertidumbre , Familia , Femenino , Edad Gestacional , Humanos , Hipoxia-Isquemia Encefálica/etiología , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Cuidados Paliativos , Consentimiento Paterno/ética , Pronóstico , Estenosis de la Válvula Pulmonar/cirugía , Valores Sociales , Privación de Tratamiento/ética
13.
Am Fam Physician ; 94(4): 276-82, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27548592

RESUMEN

Behavioral and psychological symptoms of dementia pose management challenges for caregivers and clinicians. Firstline nonpharmacologic treatments include eliminating physical and emotional stressors, modifying the patient's environment, and establishing daily routines. Family members and caregivers benefit from education about dementia symptoms and reminders that the behaviors are normal and unintentional. Cognitive and emotion-oriented interventions, sensory stimulation interventions, behavior management techniques, and other psychosocial interventions are modestly effective. In refractory cases, physicians may choose to prescribe off-label antipsychotics. Aripiprazole has the most consistent evidence of symptom improvement; however, this improvement is small. Olanzapine, quetiapine, and risperidone have inconsistent evidence of benefit. Physicians should use the smallest effective dose for the shortest possible duration to minimize adverse effects, most notably an increased mortality risk. Other adverse effects include anticholinergic and antidopaminergic effects, extrapyramidal symptoms, neuroleptic malignant syndrome, postural hypotension, metabolic syndrome, cardiac arrhythmia, and sedation. Patients should be monitored for these effects while receiving treatment; however, laboratory monitoring may be limited to patients receiving long-term therapy.


Asunto(s)
Antipsicóticos/uso terapéutico , Terapia Cognitivo-Conductual , Demencia/terapia , Trastornos Psicóticos/terapia , Aripiprazol/uso terapéutico , Arritmias Cardíacas/inducido químicamente , Enfermedades de los Ganglios Basales/inducido químicamente , Terapia Conductista , Benzodiazepinas/uso terapéutico , Demencia/psicología , Emociones , Humanos , Hipotensión Ortostática/inducido químicamente , Síndrome Metabólico/inducido químicamente , Síndrome Neuroléptico Maligno/etiología , Olanzapina , Guías de Práctica Clínica como Asunto , Trastornos Psicóticos/psicología , Fumarato de Quetiapina/uso terapéutico , Risperidona/uso terapéutico
14.
Fam Med ; 47(5): 343-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25905875

RESUMEN

BACKGROUND AND OBJECTIVES: Deployment away from regular clinical practice is necessary for Army family physicians, but no current information identifies specific procedures or clinical encounters where they feel less comfortable after deployment. This study identifies specific clinical areas and amount of perceived degradation in skills after deployment to combat zones. METHODS: Active duty Army family physicians were invited to participate in a web-based and anonymous survey rating comfort level performing clinical encounters or procedures prior to and after military deployment. Participants rated their comfort level using a 5-point Likert scale. The analysis included descriptive statistics about each physician's deployment history. The composite data for each clinical encounter or procedure were analyzed with McNemar's Chi-Square test. RESULTS: A total of 179 eligible Army family physicians (54% of total) fully completed the instrument, with 39% deploying once and 10% deploying more than five times in their career. Deployments ranged from 1 to >24 months, with 42% having a last deployment of 12 months duration. With statistical significance, providers reported being less comfortable post-deployment with managing first-trimester bleeding, ACLS codes, acute abdominal pain, asthma exacerbations, central line placement, chest pain, COPD exacerbations, CVA/hypertensive emergency, lumbar puncture, neonatal fevers, pediatric codes, sepsis/septic shock, and vaginal delivery. These physicians reported statistically significant increased comfort with the care of major trauma after deployment. CONCLUSIONS: Family physicians deploying to support combat operations feel less comfortable with critical clinical skills across the spectrum of care. Refresher training could be provided with standardized approach to these needs with a goal of maintaining full scope primary care providers.


Asunto(s)
Competencia Clínica , Medicina Militar , Administración de Personal , Médicos de Familia , Reinserción al Trabajo/psicología , Actitud del Personal de Salud , Estudios Transversales , Humanos , Medicina Militar/métodos , Medicina Militar/organización & administración , Administración de Personal/métodos , Administración de Personal/normas , Médicos de Familia/psicología , Médicos de Familia/normas , Autoeficacia , Estados Unidos
15.
Oncotarget ; 6(11): 8777-87, 2015 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-25669972

RESUMEN

Functional alterations in Rad51C are the cause of the Fanconi anemia complementation group O (FANCO) gene disorder. We have identified novel splice variants of Rad51C mRNA in colorectal tumors and cells. The alternatively spliced transcript variants are formed either without exon-7 (variant 1), without exon 6 and 7 (variant 2) or without exon 7 and 8 (variant 3). Real time PCR analysis of nine pair-matched colorectal tumors and non-tumors showed that variant 1 was overexpressed in tumors compared to matched non-tumors. Among 38 colorectal tumor RNA samples analyzed, 18 contained variant 1, 12 contained variant 2, 14 contained variant 3, and eight expressed full length Rad51C exclusively. Bisulfite DNA sequencing showed promoter methylation of Rad51C in tumor cells. 5-azacytidine treatment of LS-174T cells caused a 14 fold increase in variant 1, a 4.8 fold increase for variant 3 and 3.4 fold for variant 2 compared to 2.5 fold increase in WT. Expression of Rad51C variants is associated with FANCD2 foci positive colorectal tumors and is associated with microsatellite stability in those tumors. Further investigation is needed to elucidate differential function of the Rad51C variants to evaluate potential effects in drug resistance and DNA repair.


Asunto(s)
Adenocarcinoma/genética , Empalme Alternativo , Neoplasias Colorrectales/genética , Proteínas de Unión al ADN/genética , Proteínas de Neoplasias/genética , Adenocarcinoma/patología , Secuencia de Aminoácidos , Azacitidina/farmacología , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Metilación de ADN/efectos de los fármacos , Reparación del ADN , ADN de Neoplasias/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/fisiología , Exones/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/análisis , Perfilación de la Expresión Génica , Humanos , Análisis por Apareamiento , Inestabilidad de Microsatélites , Datos de Secuencia Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/fisiología , Regiones Promotoras Genéticas/genética , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiología , Estructura Terciaria de Proteína , ARN Mensajero/genética , ARN Neoplásico/genética
16.
PLoS One ; 7(10): e40483, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23071485

RESUMEN

The brain is one of the most studied and highly complex systems in the biological world. While much research has concentrated on studying the brain directly, our focus is the structure of the brain itself: at its core an interconnected network of nodes (neurons). A better understanding of the structural connectivity of the brain should elucidate some of its functional properties. In this paper we analyze the connectome of the nematode Caenorhabditis elegans. Consisting of only 302 neurons, it is one of the better-understood neural networks. Using a Laplacian Matrix of the 279-neuron "giant component" of the network, we use an eigenvalue counting function to look for fractal-like self similarity. This matrix representation is also used to plot visualizations of the neural network in eigenfunction coordinates. Small-world properties of the system are examined, including average path length and clustering coefficient. We test for localization of eigenfunctions, using graph energy and spacial variance on these functions. To better understand results, all calculations are also performed on random networks, branching trees, and known fractals, as well as fractals which have been "rewired" to have small-world properties. We propose algorithms for generating Laplacian matrices of each of these graphs.


Asunto(s)
Conectoma , Fractales , Red Nerviosa/fisiología , Algoritmos , Animales , Caenorhabditis elegans , Sinapsis Eléctricas , Redes Neurales de la Computación , Vías Nerviosas/fisiología , Neuronas , Sinapsis
17.
Crit Care Med ; 40(9): 2590-4, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22732283

RESUMEN

OBJECTIVE: Critically ill patients frequently display impaired decision-making capacity due to their underlying illness and the use of sedating medications. Healthcare providers often rely on surrogates to make decisions for medical care and participation in clinical research. However, the accuracy of surrogate decisions for a variety of critical care research studies is poorly understood. DESIGN: Cross-sectional observational study. SETTING: Academic medical center. PATIENTS: Medical intensive care unit patients and their designated surrogates. INTERVENTION: Patients were asked whether they would consent to participate in hypothetical research studies of increasing complexity, and surrogates independently indicated whether they would consent to enroll the patient in the same scenarios. RESULTS: Overall, 69 medical intensive care unit patients were enrolled into the study. The majority of surrogates were either the spouse (58%) or parent (22%) of the patient. The percentage of patients that would agree to participate in a research study and the percentage of surrogates that would agree to have the patient enrolled into a research study both declined as the risk of the study increased (p < .001 for both analyses). In addition, the overall discrepancy, the false-negative rates, and the false-positive rates between patient and surrogates were greater as the risk of the study increased (p < .001, p < .001, and p = .049, respectively). κ values for all seven scenarios demonstrated less-than-moderate agreement (range 0.03-0.41). CONCLUSIONS: There are significant discrepancies in the willingness to participate in various types of clinical research proposals between critically ill patients and their surrogate decision makers. The results of this study raise concerns about the use of surrogate consent for inclusion of critically ill patients into research protocols.


Asunto(s)
Investigación Biomédica/ética , Toma de Decisiones/ética , Consentimiento Informado/normas , Unidades de Cuidados Intensivos , Prioridad del Paciente , Consentimiento por Terceros , Centros Médicos Académicos , Adulto , Investigación Biomédica/normas , Cuidados Críticos/métodos , Enfermedad Crítica/mortalidad , Enfermedad Crítica/terapia , Estudios Transversales , Femenino , Humanos , Consentimiento Informado/ética , Masculino , Persona de Mediana Edad , Relaciones Profesional-Familia , Apoderado , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Estados Unidos
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