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1.
Public Health ; 129(10): 1383-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24099716

RESUMEN

Scientific investigations have progressively refined our understanding of the influence of the environment on human health, and the many adverse impacts that human activities exert on the environment, from the local to the planetary level. Nonetheless, throughout the modern public health era, health has been pursued as though our lives and lifestyles are disconnected from ecosystems and their component organisms. The inadequacy of the societal and public health response to obesity, health inequities, and especially global environmental and climate change now calls for an ecological approach which addresses human activity in all its social, economic and cultural complexity. The new approach must be integral to, and interactive, with the natural environment. We see the continuing failure to truly integrate human health and environmental impact analysis as deeply damaging, and we propose a new conceptual model, the ecosystems-enriched Drivers, Pressures, State, Exposure, Effects, Actions or 'eDPSEEA' model, to address this shortcoming. The model recognizes convergence between the concept of ecosystems services which provides a human health and well-being slant to the value of ecosystems while equally emphasizing the health of the environment, and the growing calls for 'ecological public health' as a response to global environmental concerns now suffusing the discourse in public health. More revolution than evolution, ecological public health will demand new perspectives regarding the interconnections among society, the economy, the environment and our health and well-being. Success must be built on collaborations between the disparate scientific communities of the environmental sciences and public health as well as interactions with social scientists, economists and the legal profession. It will require outreach to political and other stakeholders including a currently largely disengaged general public. The need for an effective and robust science-policy interface has never been more pressing. Conceptual models can facilitate this by providing theoretical frameworks and supporting stakeholder engagement process simplifications for inherently complex situations involving environment and human health and well-being. They can be tools to think with, to engage, to communicate and to help navigate in a sea of complexity. We believe models such as eDPSEEA can help frame many of the issues which have become the challenges of the new public health era and can provide the essential platforms necessary for progress.


Asunto(s)
Ecosistema , Salud Pública , Cambio Climático , Humanos
2.
Public Health ; 123(4): 306-10, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19324380

RESUMEN

OBJECTIVES: To explore some of the strengths and weaknesses of purely quantitative approaches used in health impact assessment (HIA) and the implication of this for policy making. STUDY DESIGN: The studies presented generally used a variety of quantitative risk assessment (QRA) methodologies. METHODS: For each population, concentration-response (CR) or exposure-response (ER) functions, typically expressed as percentage change in health effect per unit change in concentration or exposure, were applied to estimates of population exposure and background rates of morbidity and mortality in order to calculate the attributable health impact or burden. In some cases, this burden was then costed according to standard economic models. RESULTS: In most of the studies discussed, where a reliable CR or ER relationship was available, it was possible to quantify the impact(s) of the relevant environmental stressors on health, and to estimate the associated uncertainties. CONCLUSIONS: QRA has an important role in producing estimates for the health impacts of those risk factors where there is a sufficient base of research to quantify relationships between population exposure and health, and to predict the effects of policies on population exposure. However, quantified HIA is not an infallible process and can give an illusion of certainty that belies the complexity of the interactions involved, particularly where multiple determinants of health are likely to be affected. It is important that any uncertainties associated with that which has been quantified, as well as the likely impacts of that which cannot be quantified, are assessed and represented comprehensively. A simplistic application of QRA estimates is an inadequate HIA, as it may encourage policy makers and others to attach more importance to those impacts that are easier to quantify but which do not necessarily have the greatest associated burden.


Asunto(s)
Técnicas de Apoyo para la Decisión , Formulación de Políticas , Salud Pública/métodos , Medición de Riesgo/métodos , Contaminación del Aire/efectos adversos , Humanos , Exposición por Inhalación/efectos adversos , Irlanda/epidemiología , Plomo/efectos adversos , Contaminación del Agua/efectos adversos
3.
Arch Intern Med ; 159(21): 2542-50, 1999 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-10573044

RESUMEN

CONTEXT: Leflunomide is a reversible inhibitor of de novo pyrimidine synthesis shown to be effective in a phase 2 trial in 402 patients with active rheumatoid arthritis (RA). OBJECTIVE: To compare the efficacy and safety of leflunomide treatment with placebo and methotrexate treatment in patients with active RA. DESIGN: Randomized, double-blind, placebo, and active-controlled 12-month study. SETTING: Forty-seven university and private rheumatology practices in the United States and Canada. PATIENTS: Diagnosis of RA by the American College of Rheumatology (ACR) criteria for duration of 6 months or longer and no previous methotrexate treatment. INTERVENTION: Leflunomide treatment (20 mg/d), placebo, or methotrexate treatment (7.5-15 mg/wk). MAIN OUTCOME MEASURES: American College of Rheumatology success rate (completed 52 weeks of treatment and met the ACR > or = 20% response criteria), disease progression as assessed by x-ray films, and improvement in function and health-related quality of life using the intent-to-treat population. RESULTS: The 482 patients studied were predominantly women (mean age, 54 years; mean disease duration, 6.7 years) for whom a mean of 0.8 disease-modifying antirheumatic drugs had failed. The ACR response and success rates for patients receiving leflunomide treatment (52% and 41%, respectively) and methotrexate treatment (46% and 35%, respectively) were significantly higher than those for patients receiving placebo (26% and 19%, respectively) (P<.001), and they were statistically equivalent, with mean time to initial response at 8.4 weeks for patients receiving leflunomide vs 9.5 weeks for patients receiving methotrexate therapy. X-ray analyses demonstrated less disease progression with leflunomide (P=.001) and methotrexate (P = .02) therapy than with placebo. Leflunomide and methotrexate treatment improved measures of physical function and health-related quality of life significantly more than placebo (P<.001 and P<.05, respectively). Common adverse events for patients receiving leflunomide treatment included gastrointestinal complaints, skin rash, and reversible alopecia. Asymptomatic transaminase elevations resulted in treatment discontinuations for 7.1% of patients receiving leflunomide therapy, 1.7% of patients receiving placebo, and 3.3% of patients receiving methotrexate therapy. CONCLUSIONS: Clinical responses following administration of leflunomide, a new therapeutic agent for the treatment of RA, were statistically superior to those with placebo and equivalent to those with methotrexate treatment. Both active treatments improved signs and symptoms of active RA, delayed disease progression as demonstrated by x-ray films, and improved function and health-related quality of life.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Isoxazoles/uso terapéutico , Metotrexato/uso terapéutico , Adulto , Anciano , Artritis Reumatoide/enzimología , Método Doble Ciego , Femenino , Humanos , Leflunamida , Masculino , Persona de Mediana Edad , Transaminasas/sangre , Resultado del Tratamiento
4.
J Thorac Cardiovasc Surg ; 80(2): 302-7, 1980 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7401682

RESUMEN

Several techniques have evolved for the cannulation of the ascending aorta for cardiopulmonary bypass. Although the theoretical risk of air embolization related to cannulation of the aorta has been alluded to in the past, studies of this problem have not previously been reported. Using a mock circulatory circuit, we found that cannulation with an empty clamped cannula caused a mean embolization of 0.0435 cc of air per cannulation compared to 0.0142 cc with a saline filled cannula and 0.0045 cc with a vented cannula. The residual amount of air which embolized in the ideally vented cannula was caused by the air pocket found within the aorta above a tangentially applied excluding clamp and could be eliminated completely by not clamping the aorta.


Asunto(s)
Cateterismo/efectos adversos , Embolia Aérea/etiología , Cateterismo/instrumentación , Cateterismo/métodos , Humanos , Modelos Anatómicos , Riesgo
5.
J AOAC Int ; 84(3): 666-70, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11417628

RESUMEN

Surveys of cosmetic raw materials and finished products for the presence of the carcinogen 1,4-dioxane have been conducted by the U.S. Food and Drug Administration since 1979. Analytical methods are described for the determination of 1,4-dioxane in ethoxylated cosmetic raw materials and cosmetic finished products. 1,4-Dioxane was isolated by azeotropic atmospheric distillation and determined by gas chromatography using n-butanol as an internal standard. A solid-phase extraction procedure based on a previously published method for the determination of 1,4-dioxane in cosmetic finished products was also used. 1,4-Dioxane was found in ethoxylated raw materials at levels up to 1410 ppm, and at levels up to 279 ppm in cosmetic finished products. Levels of 1,4-dioxane in excess of 85 ppm in children's shampoos indicate that continued monitoring of raw materials and finished products is warranted.


Asunto(s)
Carcinógenos/análisis , Cosméticos/química , Dioxanos/análisis , 1-Butanol , Fenómenos Químicos , Química Física , Cromatografía de Gases/métodos , Preparaciones para el Cabello/química , Estados Unidos , United States Food and Drug Administration
6.
IEEE Trans Med Imaging ; 33(4): 875-81, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24710156

RESUMEN

Proton radiography has applications in patient alignment and verification procedures for proton beam radiation therapy. In this paper, we report an experiment which used 200 MeV protons to generate proton energy-loss and scattering radiographs of a hand phantom. The experiment used the first-generation proton computed tomography (CT) scanner prototype, which was installed on the research beam line of the clinical proton synchrotron at Loma Linda University Medical Center. It was found that while both radiographs displayed anatomical details of the hand phantom, the energy-loss radiograph had a noticeably higher resolution. Nonetheless, scattering radiography may yield more contrast between soft and bone tissue than energy-loss radiography, however, this requires further study. This study contributes to the optimization of the performance of the next-generation of clinical proton CT scanners. Furthermore, it demonstrates the potential of proton imaging (proton radiography and CT), which is now within reach of becoming available as a new, potentially low-dose medical imaging modality.


Asunto(s)
Mano/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Protones , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos , Dosis de Radiación , Tomografía Computarizada por Rayos X/instrumentación
8.
Osteoarthritis Cartilage ; 14(9): 859-66, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16626978

RESUMEN

OBJECTIVE: Five double-blind, randomized, saline-controlled trials (RCTs) were included in the United States marketing application for an intra-articular hyaluronan (IA-HA) product for the treatment of osteoarthritis (OA) of the knee. We report an integrated analysis of the primary Case Report Form (CRF) data from these trials. METHOD: Trials were similar in design, patient population and outcome measures - all included the Lequèsne Algofunctional Index (LI), a validated composite index of pain and function, evaluating treatment over 3 months. Individual patient data were pooled; a repeated measures analysis of covariance was performed in the intent-to-treat (ITT) population. Analyses utilized both fixed and random effects models. Safety data from the five RCTs were summarized. RESULTS: A total of 1155 patients with radiologically confirmed knee OA were enrolled: 619 received three or five IA-HA injections; 536 received "placebo" saline injections. In the active and control groups, mean ages were 61.8 and 61.4 years; 62.4% and 58.8% were women; baseline total Lequèsne scores 11.03 and 11.30, respectively. Integrated analysis of the pooled data set found a statistically significant reduction (P < 0.001) in total Lequèsne score with hyaluronan (HA) (-2.68) vs placebo (-2.00); estimated difference -0.68 (95% CI: -0.56 to -0.79), effect size 0.20. Additional modeling approaches confirmed robustness of the analyses. CONCLUSIONS: This integrated analysis demonstrates that multiple design factors influence the results of RCTs assessing efficacy of intra-articular (IA) therapies, and that integrated analyses based on primary data differ from meta-analyses using transformed data.


Asunto(s)
Ácido Hialurónico/administración & dosificación , Osteoartritis de la Rodilla/tratamiento farmacológico , Anciano , Método Doble Ciego , Control de Medicamentos y Narcóticos , Femenino , Humanos , Ácido Hialurónico/efectos adversos , Ácido Hialurónico/uso terapéutico , Inyecciones Intraarticulares , Masculino , Persona de Mediana Edad , Dolor/inducido químicamente , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
9.
J Rheumatol ; 27(2): 544-8; discussion 552, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10685831

RESUMEN

Missing data in controlled clinical trials may create uncertainty in the results of a study based on non-missing data. We used 4 approaches of sensitivity analysis to address this problem. Radiographic progression data were used from a randomized controlled trial of patients with rheumatoid arthritis treated with leflunomide, methotrexate, or placebo for 12 months as an example. The mean change from baseline of the Sharp total radiographic score was the primary efficacy variable for the evaluation of leflunomide in comparison with placebo in the retardation of radiographic progression. Computer simulations were used in some of these approaches. The proportion of missing radiographic data was 26.4%. Result from the non-missing data showed that leflunomide was highly statistically significantly better than placebo in the retardation of radiographic progression. Results from the sensitivity analysis showed that radiographic data are sufficiently robust that it is unlikely that the missing data would have changed the conclusions from the analysis based on non-missing data. The potential effect of missing data in the results of a clinical trial may be addressed by various methods of sensitivity analysis. Computer simulation can be a useful tool in some of these approaches.


Asunto(s)
Artritis Reumatoide/diagnóstico por imagen , Metaanálisis como Asunto , Radiografía/métodos , Artritis Reumatoide/tratamiento farmacológico , Humanos
10.
Soc Work Health Care ; 5(1): 51-8, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-515891

RESUMEN

This paper deals with the crisis of cancer and the communication loss faced by the laryngectomized patient. It considers the particular issues for the patient and his family and how the use of crisis intervention can reinforce the coping patterns of the patient and his family.


Asunto(s)
Neoplasias de Cabeza y Cuello/psicología , Adaptación Psicológica , Adulto , Intervención en la Crisis (Psiquiatría) , Mecanismos de Defensa , Femenino , Humanos , Masculino , Ajuste Social , Asistencia Social en Psiquiatría , Estrés Psicológico/psicología
11.
NIDA Res Monogr ; (9): 163-71, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-794717

RESUMEN

In 17 studies of naltrexone, a totoal of 1,536 patients had been logged in as potential study subjects as of February 29, 1976. Of these, 883 had been started on study medication, including 107 on placebo as controls. A relatively high rate of attrition was seen in all studies over the first two months of study medication; this attrition rate tended to flatten out at about the fourth month. Of the 883 subjects beginning study medication, 47 (5.3%) were subsequently terminated for medical reasons. The data available on 45 of these subjects indicate equivalent percentages, both with respect to the total number of dropouts in the two study medication groups (naltrexone: 39 of 676, or 5.0%; placebo: 6 of 107, or 5.6%) and to the number of dropouts which the clinic reported as "possibly drug-related" (naltrexone: 6 out of 676, or 0.9%; placebo: 1 of 107, or 0.9%). However, one of the "possibly drug-related" dropouts developed idiopathic thrombocytopenic purpura after the administration of naltrexone for approximately 13 months during four separate treatment admissions. Statistical review of the data and subsequent analyses of the five double-blind, placebo-controlled studies administered by the National Academy of Sciences revealed no significant medication-group differences with respect to the physical/psychiatric or laboratory data. A review of the symptom data and analyses indicates that the frequency of occurrences of certain of the gastrointestinal tract symptoms recorded was somewhat higher in those subjects treated with naltrexone. Specific symptoms involved included "Loss of Appetite", "Abdominal Pain or Cramps", "Nausea or Vomiting", and "Constipation". However, the relative severity of these symptoms for all subjects experiencing any symptomatology was not statistically differentiable with respect to study medication group.


Asunto(s)
Naloxona/análogos & derivados , Naltrexona/uso terapéutico , Ensayos Clínicos como Asunto , Esquema de Medicación , Humanos , Naltrexona/administración & dosificación , Naltrexona/efectos adversos , Pacientes Desistentes del Tratamiento , Estadística como Asunto , Trastornos Relacionados con Sustancias/rehabilitación
12.
Risk Anal ; 18(4): 377-83, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9775447

RESUMEN

Health risks from fossil, renewable and nuclear reference energy systems are estimated following a detailed impact pathway approach. Using a set of appropriate air quality models and exposure-effect functions derived from the recent epidemiological literature, a methodological framework for risk assessment has been established and consistently applied across the different energy systems, including the analysis of consequences from a major nuclear accident. A wide range of health impacts resulting from increased air pollution and ionizing radiation is quantified, and the transferability of results derived from specific power plants to a more general context is discussed.


Asunto(s)
Fuentes Generadoras de Energía , Centrales Eléctricas , Salud Pública , Medición de Riesgo , Contaminación del Aire/análisis , Contaminación Radiactiva del Aire , Electricidad , Exposición a Riesgos Ambientales , Europa (Continente) , Combustibles Fósiles , Humanos , Modelos Biológicos , Energía Nuclear , Exposición Profesional , Radiación Ionizante , Liberación de Radiactividad Peligrosa , Estados Unidos
13.
Int J Cosmet Sci ; 16(2): 61-76, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19250497

RESUMEN

Synopsis The adequacy of preservation of seven previously unopened commercial cosmetic products was tested by individual challenges with Aspergillus niger ATCC 9642, Candida albicans ATCC 10231, Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 15422, and Staphylococcus aureus ATCC 6538, using the Cosmetic, Toiletry, and Fragrance Association (CTFA) method. Each product was consecutively challenged three times, 28 days apart. Inoculated composite products were counted by conventional techniques at eight prefixed intervals. Six of seven cosmetics passed the CTFA acceptance criteria. On the basis of viable counts seven days after inoculation (CTFA criteria), the products were classified as follows: five products were well preserved, one was marginally preserved, and one was poorly preserved. The poorly preserved product failed the CTFA criteria for all three bacteria tested. Concentrations of preservative ingredients in uninoculated composites were determined by high performance liquid chromatography. All preservatives listed on the labels of the seven cosmetic products were identified by chemical analysis. Tentative in-use validation of the CTFA criteria was performed for three of the seven cosmetic formulations. The results suggested that some cosmetic products may be underpreserved.

14.
Arthritis Rheum ; 43(3): 495-505, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10728741

RESUMEN

OBJECTIVE: To determine whether treatment with leflunomide (LEF), methotrexate (MTX), or sulfasalazine (SSZ) for 6-12 months retards progression of radiographic damage and to identify clinical variables that correlate with radiographic progression. METHODS: Radiographs of the hands and feet were performed at baseline and at the end of study or early exit in 3 randomized controlled trials. Protocol US301 was a 12-month controlled trial of LEF or MTX treatment compared with placebo in 482 patients randomized in a 3:3:2 ratio. Protocol MN301 compared 6 months of LEF or SSZ treatment with placebo in 358 patients, randomized in a 3:3:2 ratio, with continued blinded treatment in the active control arms for 12 months. Protocol MN302 compared 12 months of LEF treatment with MTX in 999 patients. Radiographs were blinded for sequence and treatment and were scored for erosions and joint space narrowing. All analyses were by intent-to-treat. Sensitivity analyses were performed to account for missing data. RESULTS: LEF, MTX, and SSZ treatment resulted in statistically significantly less radiographic progression compared with placebo at 6 and 12 months: for protocol US301, LEF versus placebo P = 0.0007 and MTX versus placebo P = 0.0196; for protocol MN301, LEF versus placebo P = 0.0004 and SSZ versus placebo P = 0.0484. The effect of LEF treatment was similar to that of MTX and SSZ. CONCLUSION: These are the first 6- and 12-month randomized placebo- and active drug-controlled trials to demonstrate retardation of radiographic progression by a new disease-modifying antirheumatic drug (DMARD), LEF, as well as 2 commonly used DMARDs, MTX and SSZ.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Isoxazoles/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/diagnóstico por imagen , Progresión de la Enfermedad , Humanos , Leflunamida , Metotrexato/uso terapéutico , Placebos , Radiografía , Sulfasalazina/uso terapéutico
15.
Occup Environ Med ; 59(7): 434-41, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12107290

RESUMEN

OBJECTIVES: To classify clinical diseases of the subjects with abnormal indices of peripheral neuropathy identified in field studies of sheep farmers and dippers exposed to organophosphate pesticides. To explore what neuropsychological profiles, if any, may be associated with neurophysiological damage in these subjects. METHODS: A case-control study (79 subjects) nested within the cross sectional study (685 subjects) of sheep farmers from the field study. Three groups with no, possible, and probable or definite neuropathy according to field studies were recruited. Investigations comprised symptoms of neuropathy, neurologial signs, motor and sensory nerve conduction, electromyography, quantitative sensory testing, and neuropsychological tests. RESULTS: The incidence of clinical neuropathy increased from 7% in the no neuropathy group to 52% in the probable or definite neuropathy group based on nerve conduction measurements or presence of neurological signs. Sensory abnormalities were found more often than motor deficits. Small diameter nerve fibres were also affected more than large fibres. CONCLUSIONS: The neuropathy is predominantly sensory and is characteristic of distal, chronic neuropathy with no acute features. Small fibre populations are affected more than large fibre populations. Increasing severity of neuropathy was associated with anxiety and depression as measured in the neuropsychological tests.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/inducido químicamente , Crianza de Animales Domésticos , Insecticidas/efectos adversos , Compuestos Organofosforados , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Adolescente , Adulto , Anciano , Enfermedades de los Trabajadores Agrícolas/diagnóstico , Enfermedades de los Trabajadores Agrícolas/fisiopatología , Animales , Estudios de Casos y Controles , Estudios Transversales , Técnicas de Diagnóstico Neurológico , Electromiografía/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/efectos de los fármacos , Pruebas Neuropsicológicas , Exposición Profesional/efectos adversos , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Trastornos de la Sensación/inducido químicamente , Trastornos de la Sensación/diagnóstico , Trastornos de la Sensación/fisiopatología , Ovinos
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