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1.
Conserv Biol ; 34(3): 733-742, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31943349

RESUMEN

Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation.


Consideraciones y Retos Importantes en la Aplicación de la Investigación por medio de Redes Sociales para la Toma de Decisiones Ambientales Resumen Los intentos por tener un mejor entendimiento del contexto social en el que se toman las decisiones ambientales y de conservación han derivado en un incremento en el interés por las redes sociales humanas. Para mejorar el uso del análisis de redes sociales en la conservación, buscamos en la literatura los estudios recientes que hayan aplicado dichos métodos y los sometimos a una revisión. En esta revisión, examinamos los problemas en el diseño de la investigación y del análisis que limitan la utilidad del análisis de redes. Diecinueve de los 55 artículos publicados entre enero 2016 y junio 2019 exhibieron al menos uno de los siguientes problemas: aplicación de métodos analíticos inadecuados o sensibles a la información incompleta sobre las redes; aplicación de estrategias estadísticas que ignoran la dependencia en la red; o falta de conexión entre la base teórica, la pregunta de investigación y la selección de técnica analítica. Al llamar la atención hacia estas áreas específicas de interés y resaltar las fronteras y retos de la investigación, incluyendo la causalidad, las dinámicas de redes y las estrategias nuevas, respondimos a la necesidad de incrementar la aplicación rigurosa de las ciencias sociales en la conservación.


Asunto(s)
Conservación de los Recursos Naturales , Ciencias Sociales , Toma de Decisiones , Humanos , Organizaciones , Medio Social
2.
Pediatr Allergy Immunol ; 22(1 Pt 1): 31-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21261742

RESUMEN

We compared responses of children and parents to determine their level of agreement in a national, population-based survey regarding asthma-related health of US children. A telephone-based survey was conducted in 2004 among a national probability sample of children with current asthma in the United States. To compare responses between parent-child pairs, a subset of 284 children aged 10-15 were interviewed in addition to the parents. This survey collected data on asthma symptom prevalence, physical activity limitations and impact of exercise on asthma, and asthma management including medication use. Paired responses were compared using the kappa (κ) statistic. Overall, parents of 10-15-yr-olds underestimated the burden of asthma experienced by their children, especially the effects on physical activity. More than half (58%) of children replied that exercise was a trigger for their asthma compared to only 35% of parents (κ 0.23). Children were more likely than parents to mention activity limitations, specifically avoiding physical exertion (63% vs. 49%-κ 0.004). Prevalence of symptoms was also underreported by parents relative to children, particularly breathing problems (41% vs. 67%-κ 0.16) and cough (45% vs. 64%-κ 0.14). Maintenance therapy use in the past 4 weeks was reported by 35% of children, whereas 44% of parents believed their children had used maintenance therapy (κ 0.47). Relative to children's self-report, parents underestimated avoidance tactics used by their children with asthma, including exercise and physical activity self-limitation to prevent the onset or worsening of asthma symptoms. Parents also underreported asthma symptoms of their children aged 10-15 years old and were discordant with their children regarding medication use. Increasing regular communication about asthma between child, parent, and physician is warranted to improve asthma control and overall health.


Asunto(s)
Adolescente , Asma/fisiopatología , Niño , Encuestas Epidemiológicas , Padres/psicología , Ruidos Respiratorios/fisiopatología , Adulto , Asma/diagnóstico , Asma/epidemiología , Asma Inducida por Ejercicio/diagnóstico , Asma Inducida por Ejercicio/epidemiología , Asma Inducida por Ejercicio/fisiopatología , Femenino , Humanos , Entrevistas como Asunto , Masculino , Percepción , Prevalencia , Encuestas y Cuestionarios , Teléfono , Estados Unidos
3.
Earth Space Sci ; 8(7): e2020EA001634, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34435081

RESUMEN

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. We conducted 121 research flights during five campaigns in four seasons during 2016-2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

4.
Int J Clin Pract ; 64(12): 1661-70, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20946271

RESUMEN

OBJECTIVE: Pelvic floor dysfunction (PFD) has a significant socioeconomic and healthcare cost. This study aimed to investigate current service provision for PFD in the UK, highlighting any gaps and areas for improvement to inform future service improvement. METHODS: A three-phase design comprised a scoping literature review, consultation survey with frontline practitioners from four key professional groups and an overarching synthesis. An interpretative analytical framework was informed by the concepts of interdisciplinary and interprofessional collaboration. RESULTS: Empirical evidence on PFD service provision is limited. No overarching strategic approach to PFD as a single clinical entity in the UK was identified. Two hundred and forty-three medical, nursing and physiotherapy practitioners from different clinical subspecialties participated in the survey. Access and availability to services, models of delivery and individual practice vary widely within and across the disciplines. Time restrictions, mixed professional attitudes, lack of standardisation and low investment priority were identified as major barriers to optimal service provision. Five overlapping areas for improvement are highlighted: access and availability, team working and collaboration, funding and investment, education, training and research, public and professional awareness. CONCLUSIONS: Current services are characterised by a fragmented approach with asynchronous delivery, limited investment and poor interprofessional integration. An improved service delivery model has the potential to improve outcomes through better interdisciplinary collaboration and efficient use of resources.


Asunto(s)
Atención a la Salud/organización & administración , Relaciones Interprofesionales , Trastornos del Suelo Pélvico/terapia , Medicina Basada en la Evidencia , Medicina Familiar y Comunitaria/estadística & datos numéricos , Prioridades en Salud , Humanos , Enfermeras Clínicas/estadística & datos numéricos , Diafragma Pélvico , Modalidades de Fisioterapia/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Calidad de la Atención de Salud , Reino Unido
5.
Science ; 290(5494): 1134-7, 2000 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-11073446

RESUMEN

Magnesium is a key determinant in CaCO3 mineralization; however, macroscopic observations have failed to provide a clear physical understanding of how magnesium modifies carbonate growth. Atomic force microscopy was used to resolve the mechanism of calcite inhibition by magnesium through molecular-scale determination of the thermodynamic and kinetic controls of magnesium on calcite formation. Comparison of directly measured step velocities to standard impurity models demonstrated that enhanced mineral solubility through magnesium incorporation inhibited calcite growth. Terrace width measurements on calcite growth spirals were consistent with a decrease in effective supersaturation due to magnesium incorporation. Ca(1-x)Mg(x)CO3 solubilities determined from microscopic observations of step dynamics can thus be linked to macroscopic measurements.

6.
Food Chem Toxicol ; 132: 110728, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31365888

RESUMEN

We report the data from the guideline-compliant two-year toxicology study conducted as part of the Consortium Linking Academic and Regulatory Insights on Bisphenol A Toxicity (CLARITY-BPA). BPA (0, 2.5, 25, 250, 2,500, and 25,000 µg/kg body weight (bw)/day) was administered daily by gavage in 0.3% carboxymethylcellulose vehicle to NCTR Sprague-Dawley rats from gestation day 6 through the start of parturition and then directly to pups from the day after birth until postnatal day 21 (stop-dose arm) or continuously until termination at one or two years. The stop-dose arm was included to assess the potential for any BPA effects that were due to developmental exposure. No BPA-related effects were evident in the in-life and non-histopathology data. Neoplastic and nonneoplastic lesions diagnosed in both females and males were common age-associated lesions that were variable across control and BPA-treated groups. The lack of consistent responses within the continuous- and stop-dose arms within and across tissues brought into question the plausible relationship of most of these lesions to BPA treatment. There was a possible relationship between the increased incidences of lesions in the female reproductive tract and the male pituitary and exposure to the 25,000 µg BPA/kg bw/day dose level.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Disruptores Endocrinos/toxicidad , Fenoles/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Etinilestradiol/administración & dosificación , Femenino , Genitales Femeninos/efectos de los fármacos , Masculino , Exposición Materna , Embarazo , Ratas , Ratas Sprague-Dawley
7.
Thorax ; 63(7): 599-605, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18245145

RESUMEN

INTRODUCTION: Lung function impairment may be a risk factor for cardiovascular disease (CVD) events. OBJECTIVE: To determine the relationship between the severity of airflow obstruction based on modified Global Initiative on Obstructive Lung Disease (GOLD) criteria and the prevalence and incidence or recurrence of CVD in a cohort of US adults, aged 45-64 years, from 1987 to 2001. METHODS: We analysed data from 14 681 adults using logistic regression to determine the cross sectional association between lung function impairment and prevalent CVD at baseline and Cox regression to examine the prospective association of lung function impairment at baseline with CVD over 15 years of follow-up. Models were adjusted for age, sex, race, smoking, comorbid hypertension and diabetes, cholesterol levels and fibrinogen level. RESULTS: At baseline, the crude prevalence of CVD was higher among subjects with GOLD 2 (OR 2.9, 95% CI 2.4 to 3.6) and GOLD 3 or 4 chronic obstructive pulmonary disease (COPD) (OR 3.0, 95% CI 2.0 to 4.5), compared with normal subjects. These relative risks were greatly reduced after adjusting for covariates (OR 1.4, 95% CI 1.1 to 1.8 for GOLD 2 and OR 1.3, 95% CI 0.8 to 2.1 for GOLD 3 or 4). Similarly, the association between COPD and risk of incident or recurrent CVD was much stronger in the unadjusted models (hazard ratio (HR) 2.4, 95% CI 2.1 to 2.7 for GOLD 2 and 2.9, 95% CI 2.2 to 3.9 for GOLD 3 or 4) than in the adjusted ones (HR 1.2, 95% CI 1.03 to 1.4 for GOLD 2 and 1.5, 95% CI 1.1 to 2.0 for GOLD 3 or 4). CONCLUSION: We observed a crude association between lung function impairment and prevalent and incident or recurrent CVD that was greatly reduced after adjusting for covariates, including age, sex, race, smoking, comorbid hypertension and diabetes, cholesterol levels and fibrinogen level. These data suggest that this association may be, in part, mediated through established CVD risk factors included in our adjusted models.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Anciano , Enfermedades Cardiovasculares/fisiopatología , Métodos Epidemiológicos , Volumen Espiratorio Forzado/fisiología , Humanos , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Recurrencia , Capacidad Vital/fisiología
8.
Respir Med ; 123: 94-97, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28137503

RESUMEN

An increased risk of non-fatal pneumonia has been documented in COPD patients treated with inhaled corticosteroids (ICS) in randomized clinical trials. Retrospective database analyses have been conducted to evaluate this signal in larger populations treated in the community. To understand how methodological choices may influence results in observational studies, we compared two recent Canadian studies which used health administrative databases from Quebec and Ontario and came to opposite conclusions on the risk of pneumonia in ICS treated COPD patients. Explanations for why the results of these studies diverged are explored. The Suissa analysis used RAMQ data from Quebec and showed an increased relative risk of serious pneumonia for current users of ICS compared to non users, RR = 1.69 (95% confidence interval, 1.63-1.75). The Gershon analysis used ODB data and showed no difference for pneumonia hospitalisation, RR = 1.01 (0.93-1.08). Reasons for differences in study findings include lack of validated definitions of COPD, poor selection of relevant exposure groups, channeling and confounding biases, and failure to perform on-treatment analyses for safety. CONCLUSION: Our study identifies methodological features that need consideration to increase robustness and minimize threats to internal validity of retrospective health administrative database studies.


Asunto(s)
Glucocorticoides/efectos adversos , Neumonía/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Bases de Datos Factuales , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Humanos , Ontario/epidemiología , Neumonía/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Quebec/epidemiología , Proyectos de Investigación , Estudios Retrospectivos , Medición de Riesgo/métodos
9.
Aliment Pharmacol Ther ; 20(5): 539-49, 2004 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15339325

RESUMEN

AIMS: To evaluate the impact of adjuvant biofeedback following sphincter surgery. METHODS: Thirty-eight patients were randomized into sphincter repair or sphincter repair plus biofeedback groups. Outcome measures included a symptom questionnaire, patient's rating of satisfaction with continence function and improvement, change in continence score, quality of life and anorectal physiology. Endoanal ultrasonography was also performed pre- and post-operatively. RESULTS: Immediately following surgery, there was no statistically significant difference in any of the functional or physiological variables between the groups. Continence and patient satisfaction scores improved with a mean difference of -0.48 (95% CI: -3.30-2.33, P = 0.73) and 1.03 (95% CI: -1.40-3.46, P = 0.39), respectively. Only the difference in embarrassment scores reached statistical significance (mean) 0.56 (95% CI: 0.12-0.99, P = 0.014). Resting and squeeze pressures also improved. Thirteen of 14 in the biofeedback and 11 of 17 (control) reported symptomatic improvement. In the biofeedback group, although not statistically significant continence and satisfaction scores improved and were sustained over time. In the control group, continence and satisfaction scores changed little between 3 and 12 months (P = NS). Quality of life measures improved within the biofeedback group but there was no statistical difference between the groups. CONCLUSION: Following surgery continence function improves in all patients but adjuvant biofeedback therapy improves quality of life and maintains symptomatic improvement over time.


Asunto(s)
Canal Anal/cirugía , Enfermedades del Ano/cirugía , Biorretroalimentación Psicológica , Incontinencia Fecal/cirugía , Adulto , Anciano , Enfermedades del Ano/diagnóstico por imagen , Enfermedades del Ano/fisiopatología , Endoscopía/métodos , Incontinencia Fecal/diagnóstico por imagen , Incontinencia Fecal/fisiopatología , Humanos , Persona de Mediana Edad , Satisfacción del Paciente , Calidad de Vida , Sensación/fisiología , Resultado del Tratamiento , Ultrasonografía
10.
Aliment Pharmacol Ther ; 19(7): 729-38, 2004 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15043513

RESUMEN

BACKGROUND: Ischaemic colitis has been associated with co-morbid conditions, medications, vascular surgery and advanced age in case reports and case series. Few data exist on the baseline incidence in the general population or on the increased risk imposed by these risk factors. AIM: To systematically review the literature regarding the incidence, prevalence and risk factors for ischaemic colitis. METHODS: Searches of bibliographic databases were performed independently by two investigators. Studies were included if they used population-based samples, disease-specific population samples or case-control population-based samples of adults with ischaemic colitis, and reported the incidence, prevalence or risk factors for ischaemic colitis. Eligible articles were reviewed and data were abstracted in a duplicate, independent manner. RESULTS: Four studies were identified that reported the general population incidence and four that reported the disease-specific population incidence. The incidence of ischaemic colitis in general populations ranged from 4.5 to 44 cases per 100 000 person-years. The risk was increased two- to four-fold by either prevalent irritable bowel syndrome or chronic obstructive pulmonary disease. The risk was also increased in females and in subjects of 65 years and older. CONCLUSIONS: Ischaemic colitis is uncommon in the general population. The effect sizes of the most commonly reported risk factors have not been adequately quantified in population-based studies.


Asunto(s)
Colitis Isquémica/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo
11.
Am J Trop Med Hyg ; 56(5): 554-60, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9180607

RESUMEN

Due to the lack of an animal model, previous studies of sandfly fever have relied upon human challenge trials. We examined the infectivity and potential pathogenicity of sandfly fever virus in cynomolgus monkeys (Macaca fascicularis). Three different preparations of sandfly fever virus. Sicilian strain, and a placebo were compared by different routes of administration. The most notable postchallenge clinical event was a decrease in lymphocytes in the intramuscularly challenged monkeys. Plaque-reduction neutralization responses peaked earlier in animals challenged intravenously as compared with those in animals challenged intramuscularly. There was no evidence for neurotropism or meningeal inflammation. Sandfly fever virus was infectious for cynomolgus monkeys, but produced no detectable clinical disease that might serve as a marker for animal modeling studies. On the other hand, the preclinical data provide supportive evidence for safe parenteral administration of a Sicilian strain of sandfly fever virus inoculum to humans as a challenge model for sandfly fever disease.


Asunto(s)
Fiebre por Flebótomos/fisiopatología , Animales , Temperatura Corporal , Modelos Animales de Enfermedad , Humanos , Macaca fascicularis , Masculino , Ratones , Fiebre por Flebótomos/sangre , Fiebre por Flebótomos/patología
12.
Gerontologist ; 40(1): 32-42, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10750311

RESUMEN

The authors conducted a telephone survey in 7 states to determine the prevalence of residential care specialized dementia programs (RC-SDPs) and to identify a sample of homes (n = 56) for more detailed study. The 56 homes were site visited, and data were gathered on facility administration, therapeutic environment, and characteristics of 259 randomly selected residents. Comparison data from 138 nursing home Special Care Units (NH-SCUs) and 1,340 of their residents were obtained from 4 studies conducted in the same 7 states. RC-SDPs were smaller, provided a more homelike environment, and had a higher proportion of residents paying privately, compared with NH-SCUs. Mean levels of cognitive and physical impairment among residents were higher in NH-SCUs; prevalences of psychotropic medication use and problem behaviors were similar. Among RC facilities, small homes were more homelike, provided fewer structured activities, and charged less than larger facilities. RC-SDPs include 5 types: small, independently operated homes; multiple small homes with joint administration; larger, all-dementia facilities; SDPs operated within larger, exclusively RC facilities; and RC-SDPs in multilevel facilities.


Asunto(s)
Demencia/epidemiología , Hogares para Ancianos/provisión & distribución , Casas de Salud/provisión & distribución , Instituciones Residenciales/provisión & distribución , Anciano , Demencia/terapia , Humanos , Evaluación de Necesidades/estadística & datos numéricos , Medio Social , Estados Unidos
13.
Tree Physiol ; 24(5): 493-504, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-14996654

RESUMEN

We measured component and whole-system respiration fluxes in northern hardwood (Acer saccharum Marsh., Tilia americana L., Fraxinus pennsylvanica Marsh.) and aspen (Populus tremuloides Michx.) forest stands in Price County, northern Wisconsin from 1999 through 2002. Measurements of soil, leaf and stem respiration, stem biomass, leaf area and biomass, and vertical profiles of leaf area were combined with biometric measurements to create site-specific respiration models and to estimate component and whole-system respiration fluxes. Hourly estimates of component respiration were based on site measurements of air, soil and stem temperature, leaf mass, sapwood volume and species composition. We also measured whole-system respiration from an above-canopy eddy flux tower. Measured soil respiration rates varied significantly among sites, but not consistently among dominant species (P < 0.05 and P > 0.1). Annual soil respiration ranged from 8.09 to 11.94 Mg C ha(-1) year(-1). Soil respiration varied linearly with temperature (P < 0.05), but not with soil water content (P > 0.1). Stem respiration rates per unit volume and per unit area differed significantly among species (P < 0.05). Stem respiration per unit volume of sapwood was highest in F. pennsylvanica (up to 300 micro mol m(3) s(-1)) and lowest in T. americana (22 micro mol m(3) s(-1)) when measured at peak summer temperatures (27 to 29 degrees C). In northern hardwood stands, south-side stem temperatures were higher and more variable than north-side temperatures during leaf-off periods, but were not different statistically during leaf-on periods. Cumulative annual stem respiration varied by year and species (P < 0.05) and averaged 1.59 Mg C ha(-1) year(-1). Leaf respiration rates varied significantly among species (P < 0.05). Respiration rates per unit leaf mass measured at 30 degrees C were highest for P. tremuloides (38.8 nmol g(-1) s(-1)), lowest for Ulmus rubra Muhlenb. (13.1 nmol g(-1) s(-1)) and intermediate and similar (30.2 nmol g(-1) s(-1)) for T. americana, F. pennsylvanica and Q. rubra. During the growing season, component respiration estimates were dominated by soil respiration, followed by leaf and then stem respiration. Summed component respiration averaged 11.86 Mg C ha(-1) year(-1). We found strong covariance between whole-ecosystem and summed component respiration measurements, but absolute rates and annual sums differed greatly.


Asunto(s)
Árboles/fisiología , Acer/metabolismo , Acer/fisiología , Dióxido de Carbono/metabolismo , Respiración de la Célula/fisiología , Fraxinus/metabolismo , Fraxinus/fisiología , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tallos de la Planta/metabolismo , Populus/metabolismo , Populus/fisiología , Microbiología del Suelo , Tilia/metabolismo , Tilia/fisiología , Árboles/metabolismo , Wisconsin
14.
Arch Pathol Lab Med ; 120(2): 140-55, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8712894

RESUMEN

OBJECTIVE: The source of infection or mode of transmission of Ebola virus to human index cases of Ebola fever has not been established. Field observations in outbreaks of Ebola fever indicate that secondary transmission of Ebola virus is linked to improper needle hygiene, direct contact with infected tissue or fluid samples, and close contact with infected patients. While it is presumed that the virus infects through either breaks in the skin or contact with mucous membranes, the only two routes of exposure that have been experimentally validated are parenteral inoculation and aerosol inhalation. Epidemiologic evidence suggests that aerosol exposure is not an important means of virus transmission in natural outbreaks of human Ebola fever; this study was designed to verify that Ebola virus could be effectively transmitted by oral or conjunctival exposure in nonhuman primates. MATERIALS AND METHODS: Adult rhesus monkeys (Macaca mulatta) were exposed to Ebola-Zaire (Mayinga) virus orally (N=4), conjunctivally (N=4), or by intramuscular inoculation (N=1, virus-positive control). RESULTS: Four of four monkeys exposed by the conjunctival route, three of four monkeys exposed by the oral route, and the intramuscularly inoculated positive control monkey (one of one) were successfully infected with Ebola-Zaire (Mayinga). Seven monkeys died of Ebola fever between days 7 and 8 postexposure. One monkey was given aggressive supportive therapy and a platelet transfusion; it lived until day 12 postexposure. CONCLUSIONS: Findings in this study experimentally confirm that Ebola virus can be effectively transmitted via the oral or conjunctival route of exposure in nonhuman primates.


Asunto(s)
Conjuntiva/virología , Fiebre Hemorrágica Ebola/transmisión , Boca/virología , Animales , Femenino , Fiebre Hemorrágica Ebola/patología , Fiebre Hemorrágica Ebola/virología , Inmunohistoquímica , Inyecciones Intramusculares , Macaca mulatta , Microscopía Electrónica de Rastreo , Mortalidad
15.
Arch Pathol Lab Med ; 120(2): 156-63, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8712895

RESUMEN

OBJECTIVE: The protein capsule of Yersinia pestis, known as Fraction 1 or F1, is a protective immunogen and is an assumed, but not proven, virulence factor. Our objectives were to determine if inhaled F1-negative and/or F1-positive strains of Y pestis were virulent in the African green monkey and, if so, to differentiate F1-negative from F1-positive monkeys. Because F1-negative strains have been isolated from natural sources and have caused experimental fatal disease, we felt that this information was crucial to the development of future vaccines and diagnostic tests. MATERIALS AND METHODS: Adult African green monkeys were exposed by aerosol to F1-positive (CO92, n=15) or F1-negative (CO92-C12, n=6; Java-9, n=2) Y pestis strains. RESULTS: All monkeys died 4 to 10 days postexposure and had lesions consistent with primary pneumonic plague. Antibodies to F1 antigen and other Y pestis antigens allowed us to differentiate F1-positive from F1-negative Y pestis strains in fixed tissues. CONCLUSIONS: In this study, F1 antigen was not a required virulence factor. Therefore, there may be a need for vaccines and diagnostic assays that are not solely based on the F1 antigen.


Asunto(s)
Chlorocebus aethiops , Enfermedades de los Monos/patología , Peste/veterinaria , Enfermedad Aguda , Animales , Femenino , Inmunohistoquímica , Masculino , Microscopía Electrónica , Enfermedades de los Monos/metabolismo , Peste/metabolismo , Peste/patología
16.
Arch Pathol Lab Med ; 120(2): 164-72, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8712896

RESUMEN

OBJECTIVE: To investigate the routes of entry of Venezuelan equine encephalitis (VEE) virus into the brain, we infected BALB/c mice with a virulent strain (V3000) by aerosol or subcutaneous inoculation. METHODS: Immunohistochemistry and in situ hybridization methods were used to detect VEE virus in tissues taken at daily intervals postinfection. RESULTS: In both groups, virus in the brain first appeared in olfactory regions. Aerosol exposure caused early massive infection of olfactory epithelium, which developed into bilaterally symmetrical infection of the olfactory nerves, olfactory bulbs, and lateral olfactory tracts by day 2 postinfection. After subcutaneous inoculation, VEE in the brain also appeared first in olfactory regions, but was not detected until day 3 postinfection. By day 4 postinfection, VEE viral infection had spread throughout the brain in both groups. Vascular endothelium and the choroid plexus remained uninfected during the entire study. CONCLUSIONS: Our findings suggest that VEE virus, whether given by aerosol or subcutaneously, first enters the brain through the olfactory tract.


Asunto(s)
Virus de la Encefalitis Equina Venezolana/fisiología , Aerosoles , Animales , Encéfalo/virología , Femenino , Inmunohistoquímica , Hibridación in Situ , Inyecciones Subcutáneas , Cinética , Ratones , Ratones Endogámicos BALB C
17.
Arch Pathol Lab Med ; 121(8): 865-8, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9278616

RESUMEN

OBJECTIVE: To identify alternatives to streptomycin for treating pneumonic plague, we evaluated beta-lactam antibiotics to treat experimental pneumonic plague in mice. METHODS: Mice were exposed to a lethal inhaled dose of Yersinia pestis and treated with beta-lactam antibiotics administered every 6 hours, starting 42 hours postexposure. RESULTS: The mice died or were euthanized in extremis 3 days postexposure. We observed marked bacterial filamentation of Y pestis in the tissues of mice treated with ceftazidime (10/10 mice), aztreonam (9/10 mice), or ampicillin (1/10 mice), but not in the tissues of mice treated with cefotetan, cefazolin, ceftriaxone, or saline. There was no evidence of septation of the filamentous bacteria by light or electron microscopy. The filamentous bacteria were confirmed as Y pestis based on their reactivity with rabbit anti-Y pestis F1 serum. CONCLUSIONS: Marked bacterial filamentation of Y pestis can be produced in vivo by certain beta-lactam antibiotics. This antibiotic-induced morphologic change is important because filamentous bacteria in clinical samples could possibly be confused with filamentous actinomycotic organisms.


Asunto(s)
Antibacterianos/farmacología , Flagelos/efectos de los fármacos , Peste/tratamiento farmacológico , Yersinia pestis/efectos de los fármacos , Animales , Femenino , Flagelos/ultraestructura , Pulmón/microbiología , Pulmón/patología , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica , Mortalidad , Bazo/microbiología , Bazo/ultraestructura , Yersinia pestis/aislamiento & purificación , Yersinia pestis/ultraestructura , beta-Lactamas
18.
Arch Pathol Lab Med ; 121(8): 805-19, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9278608

RESUMEN

BACKGROUND: Ebola virus has been responsible for explosive lethal outbreaks of hemorrhagic fever in both humans and nonhuman primates. Previous studies showed a predilection of Ebola virus for cells of the mononuclear phagocyte system and endothelial cells. OBJECTIVE: To examine the distribution of lesions and Ebola virus antigen in the tissues of six adult male African green monkeys (Cercopithecus aethiops) that died 6 to 7 days after intraperitoneal inoculation of Ebola-Zaire (Mayinga) virus. METHODS: Tissues were examined histologically, immunohistochemically, and ultrastructurally. RESULTS: A major novel finding of this study was that fibroblastic reticular cells were immunohistochemically and ultrastructurally identified as targets of Ebola virus infection. CONCLUSIONS: The role of Ebola virus-infected fibroblastic reticular cells in the pathogenesis of Ebola hemorrhagic fever warrants further investigation. This is especially important because of recent observations indicating that fibroblastic reticular cells, along with the reticular fibers they produce, maximize the efficiency of the immune response.


Asunto(s)
Chlorocebus aethiops/virología , Ebolavirus/aislamiento & purificación , Ebolavirus/patogenicidad , Fibroblastos/virología , Fiebre Hemorrágica Ebola/patología , Enfermedades de los Monos/patología , Glándulas Suprarrenales/ultraestructura , Glándulas Suprarrenales/virología , Animales , Antígenos Virales/análisis , Ebolavirus/inmunología , Ebolavirus/ultraestructura , Fibroblastos/ultraestructura , Fiebre Hemorrágica Ebola/transmisión , Fiebre Hemorrágica Ebola/veterinaria , Inmunohistoquímica , Hígado/ultraestructura , Hígado/virología , Pulmón/ultraestructura , Pulmón/virología , Ganglios Linfáticos/ultraestructura , Ganglios Linfáticos/virología , Masculino , Mesenterio/ultraestructura , Mesenterio/virología , Enfermedades de los Monos/etiología , Enfermedades de los Monos/transmisión , Viremia/patología
19.
J Comp Pathol ; 125(4): 233-42, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11798240

RESUMEN

Guinea-pigs and non-human primates have traditionally been used as animal models for studying Ebola Zaire virus (EBO-Z) infections. The virus was also recently adapted to the stage of lethal virulence in BALB/c mice. This murine model is now in use for testing antiviral medications and vaccines. However, the pathological features of EBO-Z infection in mice have not yet been fully described. To identify sites of viral replication and characterize sequential morphological changes in BALB/c mice, adult female mice were infected with mouse-adapted EBO-Z and killed in groups each day for 5 days post-infection. Tissues were examined by light microscopy, immunohistochemistry, electron microscopy and in-situ hybridization. As in guinea-pigs and non-human primates, cells of the mononuclear phagocytic system were the earliest targets of infection. Viral replication was observed by day 2 in macrophages in lymph nodes and spleen. By the time of onset of illness and weight loss (day 3), the infection had spread to hepatocytes and adrenal cortical cells, and to macrophages and fibroblast-like cells in many organs. Severe lymphocytolysis was observed in the spleen, lymph nodes and thymus. There was minimal infection of endothelial cells. All of these changes resembled those observed in EBO-Z-infected guinea-pigs and non-human primates. In contrast to the other animal models, however, there was little fibrin deposition in the late stage of disease. The availability of immunodeficient, "gene-knockout" and transgenic mice will make the mouse model particularly useful for studying the early steps of Ebola pathogenesis.


Asunto(s)
Ebolavirus/patogenicidad , Fiebre Hemorrágica Ebola/virología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos Virales/análisis , Modelos Animales de Enfermedad , Ebolavirus/genética , Ebolavirus/inmunología , Femenino , Fiebre Hemorrágica Ebola/patología , Técnicas para Inmunoenzimas , Hibridación in Situ , Cuerpos de Inclusión Viral/ultraestructura , Tejido Linfoide/patología , Tejido Linfoide/virología , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , ARN Viral/análisis , Proteínas del Envoltorio Viral/análisis , Replicación Viral
20.
Percept Mot Skills ; 62(1): 71-7, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3960686

RESUMEN

Data from 30 female subjects indicated that a 17.3% increase in a physical fitness index improved by 12% to 68% the information processing and decision-making capabilities of the subjects. The changes in physical fitness did not affect the performance on a variety of other tasks.


Asunto(s)
Toma de Decisiones/fisiología , Aptitud Física , Adulto , Anciano , Cognición/fisiología , Femenino , Humanos , Persona de Mediana Edad , Personalidad , Desempeño Psicomotor/fisiología , Asunción de Riesgos
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