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1.
Phys Rev Lett ; 120(24): 245003, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29956968

RESUMEN

A series of cryogenic, layered deuterium-tritium (DT) implosions have produced, for the first time, fusion energy output twice the peak kinetic energy of the imploding shell. These experiments at the National Ignition Facility utilized high density carbon ablators with a three-shock laser pulse (1.5 MJ in 7.5 ns) to irradiate low gas-filled (0.3 mg/cc of helium) bare depleted uranium hohlraums, resulting in a peak hohlraum radiative temperature ∼290 eV. The imploding shell, composed of the nonablated high density carbon and the DT cryogenic layer, is, thus, driven to velocity on the order of 380 km/s resulting in a peak kinetic energy of ∼21 kJ, which once stagnated produced a total DT neutron yield of 1.9×10^{16} (shot N170827) corresponding to an output fusion energy of 54 kJ. Time dependent low mode asymmetries that limited further progress of implosions have now been controlled, leading to an increased compression of the hot spot. It resulted in hot spot areal density (ρr∼0.3 g/cm^{2}) and stagnation pressure (∼360 Gbar) never before achieved in a laboratory experiment.

3.
Phys Rev Lett ; 117(7): 075002, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27563971

RESUMEN

Direct measurements of hydrodynamic instability growth at the fuel-ablator interface in inertial confinement fusion (ICF) implosions are reported for the first time. These experiments investigate one of the degradation mechanisms behind the lower-than-expected performance of early ICF implosions on the National Ignition Facility. Face-on x-ray radiography is used to measure instability growth occurring between the deuterium-tritium fuel and the plastic ablator from well-characterized perturbations. This growth starts in two ways through separate experiments-either from a preimposed interface modulation or from ablation front feedthrough. These experiments are consistent with analytic modeling and radiation-hydrodynamic simulations, which say that a moderately unstable Atwood number and convergence effects are causing in-flight perturbation growth at the interface. The analysis suggests that feedthrough from outersurface perturbations dominates the interface perturbation growth at mode 60.

4.
Am J Ind Med ; 58(10): 1114-25, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26305997

RESUMEN

BACKGROUND: Heat-related illness (HRI) is an occupational health risk for many outdoor, and some indoor, workers. METHODS: Emergency department (ED) and inpatient hospitalization (IH) data for 2007-2011 from nine southeast states were analyzed to identify occupational HRI numbers and rates, demographic characteristics, and co-morbid conditions. RESULTS: There were 8,315 occupational HRI ED visits (6.5/100,000 workers) and 1,051 IHs (0.61/100,000) in the southeast over the study period. Out-of-state residents comprised 8% of ED visits and 12% of IHs. Rates for both, ED visits and IHs were significantly elevated in males and blacks. Younger workers had elevated rates for ED visits, while older workers had higher IH rates. CONCLUSIONS: This is the first study to evaluate occupational HRI ED visits and IHs in the southeast region and indicates the need for enhanced heat-stress prevention policies in the southeast. Findings from this study can be used to direct state health department tracking and evaluation of occupational HRI.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Trastornos de Estrés por Calor/epidemiología , Hospitalización/estadística & datos numéricos , Enfermedades Profesionales/epidemiología , Adulto , Anciano , Femenino , Trastornos de Estrés por Calor/etiología , Trastornos de Estrés por Calor/terapia , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Enfermedades Profesionales/terapia , Estudios Retrospectivos , Factores de Riesgo , Sudeste de Estados Unidos/epidemiología
5.
Aust Vet J ; 99(4): 119-123, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33442884

RESUMEN

BACKGROUND: Brain metastases are well known for disseminated hemangiosarcoma involving the right atrium/auricle. CASE REPORT: An 8-year-old male Australian Shepherd Dog presented with a 3-day history of circling to the left. A neurological examination revealed obtunded mentation, right hemi-inattention, bilateral strabismus towards the left side and absent physiological nystagmus. In addition, the dog had muffled heart sounds on auscultation and exercise-induced weakness. Laboratory findings included hypercoagulability and marked elevation in the C-reactive protein concentration. Electrocardiography detected a sinus rhythm with right bundle-branch block and ventricular bigeminy. Echocardiography revealed an extensive interventricular septal mass. Due to the grave prognosis, the owners elected for euthanasia, and a complete necropsy was performed. The main pathological findings were an interventricular septal and left ventricular hemangiosarcoma, with metastases in the brain, lungs, spleen and adrenal glands. No evidence of tumour infiltration was found in the right atrium. CONCLUSION: To the authors' knowledge, this is the first report of neurological signs due to confirmed brain metastases in a dog with interventricular septal hemangiosarcoma. Although the right atrium is the main location for cardiac hemangiosarcoma, the interventricular septum should be evaluated in all cases.


Asunto(s)
Neoplasias Encefálicas , Enfermedades de los Perros , Hemangiosarcoma , Animales , Australia , Neoplasias Encefálicas/veterinaria , Enfermedades de los Perros/diagnóstico , Perros , Ecocardiografía/veterinaria , Electrocardiografía , Eutanasia Animal , Hemangiosarcoma/veterinaria , Masculino
6.
Accid Anal Prev ; 122: 287-294, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30396030

RESUMEN

OBJECTIVE: Drugged driving crashes have significantly increased over the past two decades. The objectives of this study were to identify and characterize the drugs present in motor vehicle driver fatalities using multiple surveillance data sources; assess concordance of the data sources in identifying drug presence; and identify demographic and crash factors associated with drug and alcohol screening in fatally injured motor vehicle drivers. METHODS: Fatality Analysis Reporting System (FARS), Collision Report Analysis for Safer Highways (CRASH), and mortality data sets were linked; drug screening and positive drug screens were identified. Chi-square and conditional logistic regression were performed. RESULTS: The use of FARS data identified the majority of positive drug screens in the linked data set. Supplementation of FARS data with death certificate and CRASH data increased identification of specific drugs and drug classes detected among fatally injured motor vehicle drivers, although there was a low concordance among the data sources. Alcohol and depressants such as alprazolam had the highest frequencies among fatally injured drivers. Speeding, lack of occupant restraints, young age, commercial truck drivers, and speeding were all factors associated with increased odds of the fatally injured driver being drug or alcohol screened. CONCLUSIONS: These findings indicate that FARS drug information data may be strengthened through increased autopsy and consultation with medical examiners to better understand and interpret decedent toxicology testing results, and that states with low driver drug testing rates should consider mandatory driver drug testing in fatal crashes.


Asunto(s)
Accidentes de Tránsito/mortalidad , Conducir bajo la Influencia/estadística & datos numéricos , Detección de Abuso de Sustancias/estadística & datos numéricos , Adolescente , Adulto , Autopsia/estadística & datos numéricos , Recolección de Datos/métodos , Femenino , Humanos , Kentucky/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
7.
Inj Epidemiol ; 5(1): 27, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-29961925

RESUMEN

BACKGROUND: Private and Public security and law enforcement (SLE) sectors perform multiple overlapping job duties. METHODS: Workers' compensation (WC) SLE first reports of injury (FROI) data (2005-2015) were analyzed to describe injuries, identify differences in awarded WC benefits, and compare the probability of a FROI resulting in awarded benefits between Public and Private SLE. A Pearson's chi-square test was utilized and reverse selection logistic regression was performed to estimate the odds ratio that a FROI would result in an awarded benefit for Private vs. Public SLE, while adjusting for relevant covariates. RESULTS: Private SLE had higher FROI percentages for younger and for older workers, fall injuries, and back injuries, compared to Public SLE. The adjusted odds that a FROI resulted in an awarded benefit was 1.4 times higher for Private SLE compared to Public SLE; (95% confidence interval [CI] = 1.09,1.69). Middle-aged SLE employee adjusted odds of awarded benefits was 3.3 times (95% CI [1.96, 5.39]) higher compared to younger employees. Adjusted odds of awarded benefits was 3.8 times (95% CI [1.34, 10.61]) higher for gunshots and 1.7 times (95% CI [1.22, 2.39]) higher for fractures/dislocations compared to other nature of injuries. Motor vehicle injury, fall/slip, and strain related FROIs had elevated adjusted odds of awarded benefits compared to other injury causes. CONCLUSIONS: Results highlight the importance of injury prevention education and worker safety training for Private and Public SLE sector workers on fall prevention (especially in Private SLE) and strain prevention (especially in Public SLE), as well as motor vehicle safety.

8.
Traffic Inj Prev ; 19(4): 446-453, 2018 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-29381397

RESUMEN

OBJECTIVE: Traffic incidents occurring on roadways require the coordinated effort of multiple responder and recovery entities, including communications, law enforcement, fire and rescue, emergency medical services, hazardous materials, transportation agencies, and towing and recovery. The objectives of this study were to (1) identify and characterize transportation incident management (TIM)-related occupational fatalities; (2) assess concordance of surveillance data sources in identifying TIM occupations, driver vs. pedestrian status, and occupational fatality incident location; and (3) determine and compare U.S. occupational fatality rates for TIM industries. METHODS: The Kentucky Fatality Assessment and Control Evaluation (FACE) program analyzed 2005-2016 TIM occupational fatality data using multiple data sources: death certificate data, Collision Report Analysis for Safer Highways (CRASH) data, and media reports, among others. Literal text analysis was performed on FACE data, and a multiple linear regression model and SAS proc sgpanel were used to estimate and visualize the U.S. TIM occupational mortality trend lines and confidence bounds. RESULTS: There were 29 TIM fatalities from 2005 to 2015 in Kentucky; 41% of decedents were in the police protection occupation, and 21% each were in the fire protection and motor vehicle towing industries. Over one half of the TIM decedents were performing work activities as pedestrians when they died. Media reports identified the majority of the occupational fatalities as TIM related (28 of 29 TIM-related deaths); the use of death certificates as the sole surveillance data source only identified 17 of the 29 deaths as TIM related, and the use of CRASH data only identified 4 of the 29 deaths as TIM related. Injury scenario text analysis showed that law enforcement vehicle pursuit, towing and recovery vehicle loading, and disabled vehicle response were particular high-risk activities that led to TIM deaths. Using U.S. data, the motor vehicle towing industry had a significantly higher risk for occupational mortality compared to the fire protection and police protection industries. CONCLUSIONS: Multiple data sources are needed to comprehensively identify TIM fatalities and to examine the circumstances surrounding TIM fatalities, because no one data source in itself was adequate and undercounted the total number of TIM fatalities. The motor vehicle towing industry, in particular, is at elevated risk for occupational mortality, and targeted mandatory TIM training for the motor vehicle towing industry should be considered. In addition, enhanced law enforcement roadside safety training during vehicle pursuit and apprehension of suspects is recommended.


Asunto(s)
Accidentes de Trabajo/mortalidad , Accidentes de Tránsito/mortalidad , Certificado de Defunción , Vehículos a Motor/estadística & datos numéricos , Accidentes de Trabajo/clasificación , Adulto , Femenino , Humanos , Kentucky/epidemiología , Masculino , Persona de Mediana Edad
9.
Vet Comp Oncol ; 15(4): 1468-1478, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28194917

RESUMEN

Sterile haemorrhagic cystitis (SHC) is a known risk of cyclophosphamide treatment. Diuresis using furosemide is effective in canines when maximally tolerated dosed cyclophosphamide is administered. This retrospective study aimed to determine whether orally administered furosemide decreased the incidence of SHC. Secondary aims were to identify predisposing factors for SHC. One-hundred and fifteen dogs treated with metronomic cyclophosphamide were analysed retrospectively. Populations were not randomized. 25 dogs (21.7%) developed SHC. Furosemide administration significantly reduced the likelihood of SHC development (P = 0.010, where SHC was diagnosed in 30.3% of dogs administered cyclophosphamide without furosemide, and 10.2% of dogs administered cyclophosphamide with furosemide). Age, gender, breed, bodyweight, number of cyclophosphamide treatments, piroxicam use and previous or pre-existing disease were not found to be associated with SHC development. This study demonstrates furosemide is effective in the prevention of SHC and its use may be considered when implementing metronomic cyclophosphamide therapy.


Asunto(s)
Antineoplásicos Alquilantes/efectos adversos , Ciclofosfamida/efectos adversos , Cistitis/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Furosemida/uso terapéutico , Administración Metronómica , Animales , Antineoplásicos Alquilantes/administración & dosificación , Ciclofosfamida/administración & dosificación , Cistitis/inducido químicamente , Cistitis/prevención & control , Enfermedades de los Perros/inducido químicamente , Enfermedades de los Perros/prevención & control , Perros , Femenino , Masculino , Neoplasias/tratamiento farmacológico , Neoplasias/veterinaria , Estudios Retrospectivos , Factores de Riesgo
10.
Accid Anal Prev ; 37(5): 862-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15921653

RESUMEN

A retrospective population-based case-control study was conducted to determine whether driver sleepiness/fatigue and inattention/distraction increase the likelihood that a commercial motor vehicle collision (CVC) will be fatal. Cases were identified as CVC drivers who died (fatal) and controls were drivers who survived (nonfatal) an injury collision using the Kentucky Collision Report Analysis for Safer Highways (CRASH) electronic database from 1998-2002. Cases and controls were matched on unit type and roadway type. Conditional logistic regression was performed. Driver sleepiness/fatigue, distraction/inattention, age of 51 years of age and older, and nonuse of safety belts increase the odds that a CVC will be fatal. Primary safety belt law enactment and enforcement for all states, commercial vehicle driver education addressing fatigue and distraction and other approaches including decreased hours-of-service, rest breaks and policy changes, etc. may decrease the probability that a CVC will be fatal.


Asunto(s)
Accidentes de Trabajo/mortalidad , Accidentes de Tránsito/mortalidad , Atención , Fatiga/epidemiología , Trastornos del Sueño del Ritmo Circadiano/epidemiología , Adulto , Distribución por Edad , Estudios de Casos y Controles , Humanos , Kentucky/epidemiología , Modelos Logísticos , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Cinturones de Seguridad/estadística & datos numéricos
11.
Toxicol Sci ; 64(1): 57-66, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11606801

RESUMEN

Previous rat studies with lead (Pb) have shown that exposure throughout the full gestational period results in persistent immunotoxicity detectable in both juvenile and adult offspring. Gender differences are also evident. However, little is known about the persistent immunotoxic effects of Pb when administered during specific stages of embryonic development. Adult Sprague-Dawley female rats were administered Pb acetate (or control acetate) in their drinking water early in gestation (days 3-9) or late in gestation (days 15-21). Significantly depressed delayed type hypersensitivity (DTH) responses as well as elevated IL-10 production, relative monocyte numbers, and increased relative thymic weights were observed in late-gestation Pb-exposed female offspring assessed as adults. In contrast, late-gestation Pb-treated male offspring had significantly increased IL-12 production and decreased IL-10 production, while the DTH response, relative monocyte numbers and thymic weights were unchanged. With early exposure, the primary alteration was decreased nitric oxide production in Pb-treated males, whereas in Pb-treated females nitrite production was unaltered. These results suggest that at the Pb dosage employed, the embryo may be more sensitive to the full range of Pb-induced immunotoxic effects with late gestational Pb exposure, and the effects of Pb on DTH function are more pronounced in females. The data also indicate that adherent splenocytes (probably macrophages) and T lymphocytes are the primary immune cells affected during fetal Pb exposure, and that gender may influence the impact of Pb exposure on these cells. Therefore, additional developmental immunotoxicity studies are needed to examine critical windows of immune development for immunotoxicity and differential susceptibility based on gender.


Asunto(s)
Citocinas/metabolismo , Embrión de Mamíferos/efectos de los fármacos , Hipersensibilidad Tardía , Plomo/toxicidad , Compuestos Organometálicos/toxicidad , Efectos Tardíos de la Exposición Prenatal , Caracteres Sexuales , Adyuvantes Inmunológicos , Animales , Huesos/química , Células Cultivadas , Concanavalina A/inmunología , Desarrollo Embrionario y Fetal , Femenino , Edad Gestacional , Hemocianinas/inmunología , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-2/metabolismo , Plomo/sangre , Recuento de Leucocitos , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Lipopolisacáridos/inmunología , Masculino , Nitritos/metabolismo , Tamaño de los Órganos , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/farmacología , Embarazo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Bazo/citología , Bazo/efectos de los fármacos , Bazo/metabolismo , Timo/inmunología , Timo/fisiología
12.
Toxicol Sci ; 42(2): 129-35, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9579025

RESUMEN

Lead has been shown to exert toxic effects during early development. In these in vivo and ex vivo experiments, the effect of lead on the immune system of the developing embryo was assessed. Nine-week-old female Fischer 344 rats were exposed to lead acetate (0, 100, 250, and 500 ppm lead) in their drinking water during breeding and pregnancy (exposure was discontinued at parturition). Offspring received no additional lead treatment after birth. Immune function was assessed in female offspring at 13 weeks of age. Dams in lead-exposed groups were not different from controls with respect to the immune endpoints used in these experiments; however, in the offspring, lead modulated important immune parameters at modest exposure levels. Macrophage cytokine and effector function properties (tumor necrosis factor-alpha and nitric oxide production) were elevated in the 250 ppm group, while cell-mediated immune function was depressed, as shown by a decrease in delayed-type hypersensitivity reactions in the 250 ppm group. Interferon-gamma levels were decreased in the 500 ppm treatment group. Serum levels of IgE were increased in rats exposed to 100 ppm lead. These results indicate that exposure of mothers to moderate levels of lead produces chronic immune modulation in their F344 rat offspring exposed in utero. Since the mothers were not susceptible to chronic immune alterations, a developmental bias to the immunotoxic effects of lead is indicated. The differences observed are consistent with the possibility that lead may bias T helper subset development and/or function, resulting in alterations in the balance among type 1 and type 2 immune responses.


Asunto(s)
Formación de Anticuerpos/efectos de los fármacos , Desarrollo Embrionario y Fetal/efectos de los fármacos , Inmunidad Celular/efectos de los fármacos , Plomo/toxicidad , Animales , Peso Corporal , Ensayo de Inmunoadsorción Enzimática , Femenino , Hipersensibilidad Tardía , Inmunoglobulina E/sangre , Interferón gamma/biosíntesis , Interleucina-2/biosíntesis , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Plomo/sangre , Recuento de Leucocitos/efectos de los fármacos , Óxido Nítrico/biosíntesis , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Endogámicas F344 , Superóxidos/metabolismo , Tibia/química , Factor de Necrosis Tumoral alfa/biosíntesis
13.
Gen Hosp Psychiatry ; 7(4): 294-301, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4065548

RESUMEN

This study evaluated the effects of a hospital-based counseling service on the physical recovery of surgical and medical patients. Their recovery was measured in terms of days on antibiotics, days to return to normal temperature, normal pulse and oral intake, and days on intravenous (IV) feeding. The effects of the sex, age, seriousness of physical problem, recovery rate, and digestive vs. genital system involvement of patients on these recovery measures were also monitored. Seriousness of physical problem proved to be the best predictor of patient recovery but, when its effects were controlled for, some beneficial effects of the counseling were observed.


Asunto(s)
Consejo , Trastornos Psicofisiológicos/terapia , Derivación y Consulta , Rol del Enfermo , Adolescente , Adulto , Femenino , Enfermedades Gastrointestinales/terapia , Enfermedades de los Genitales Femeninos/terapia , Enfermedades de los Genitales Masculinos/terapia , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/terapia , Pronóstico , Enfermedades Urológicas/terapia
14.
Soc Sci Med ; 20(11): 1199-205, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-4023757

RESUMEN

The psychological reactions of 259 female and 130 male medical and surgical patients were examined. Both when they were discharged and when they were followed up 12 months later, women who received crisis intervention counseling during their hospitalisation showed the predicted psychological gains when compared with non-counseled women. They expressed fewer feelings of helplessness and more of competence in the short term and fewer feelings of anxiety and helplessness in the long term. Men showed some improvements in the short term but fewer in the long term when, although they later expressed more feelings of competence, there were also more of helplessness. Women and men also showed the predicted benefits of counseling similarly in fewer indirect expressions of anger on both occasions. They also showed less anxiety on discharge and fewer depressive feelings on follow-up. Explanations of the sex differences in terms of sex role stereotypes, the extent of each patient's crisis and possible methodological artefacts were considered.


Asunto(s)
Consejo , Intervención en la Crisis (Psiquiatría) , Hospitalización , Pacientes/psicología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Operativos/psicología
15.
J Toxicol Environ Health A ; 61(8): 677-93, 2000 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-11132697

RESUMEN

Lead has been shown previously to induce immunotoxic effects on macrophage and T-cell-associated functions after full-gestational exposure. To gain a better understanding of a single developmental exposure and the potential role of gender in immunotoxic responses to low levels of lead, 5-d-old avian embryos were injected once with lead acetate (5 or 10 microg). As juveniles (4 wk of age), animals were immunized with a foreign antigen, bovine serum albumin (BSA). At 6 and 8 wk, animals were sensitized with a self antigen, thyroglobulin (Tg). Immune parameters were examined at 6 and 10 wk of age. In males, anti-BSA immunoglobulin G (IgG) levels were significantly increased at the highest lead treatment level compared to sodium acetate controls, while female antibody production was unaltered. Similarly, after early exposure to lead, males (which were noninducible for anti-thyroglobulin antibodies in sodium acetate controls) were induced to produce autoanti-thyroglobulin IgG. Lead exposure did not markedly alter autoantibody levels in females, although, unlike males, control females could be induced to produce autoantibody to thyroglobulin. Males differed significantly in total leukocyte counts between treatment groups, whereas females did not. No marked differences were observed in males or females in the delayed-type hypersensitivity response, lymphocytic infiltration of thyroids, or in spleen, thymus, or bursa weights following exposure to lead. These results suggest that there is a differential immunotoxic effect based on gender after a single in ovo exposure to lead. Therefore, when examining the developmental immunotoxic effects of a metal such as lead, gender is a potential risk factor.


Asunto(s)
Pollos/fisiología , Inmunoglobulina G/análisis , Plomo/toxicidad , Animales , Autoanticuerpos , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/efectos de los fármacos , Femenino , Inmunidad Celular/efectos de los fármacos , Recuento de Leucocitos , Masculino , Factores de Riesgo , Factores Sexuales
16.
J Toxicol Environ Health A ; 64(3): 223-40, 2001 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-11594701

RESUMEN

Gender-based differences in immunotoxicity induced by the heavy metal lead (Pb) have been observed both in the juvenile chicken and the adult rat following low-level exposure during embryonic development. To better define the gender-based differences, as related to dose following in utero exposure to Pb, potential differential sensitivities were examined after exposure of F344 rats to low concentrations of Pb (0, 50, 100, or 250 ppm Pb) ad libitum throughout gestation. Immune assessment was performed in juveniles (5 wk old) and young adults (13 wk old). At the highest (250 ppm) Pb concentration examined, the delayed-type hypersensitivity (DTH) response was depressed in females relative to gender-matched controls at both ages; relative spleen weights and relative neutrophil numbers were increased while relative and absolute monocyte numbers and relative basophil numbers were decreased at 13 but not 5 wk of age. In contrast, 250 ppm Pb-treated males did not differ in these endpoints. With in utero exposure to 100 ppm Pb, 13-wk-old females again had decreased relative and absolute monocyte numbers and increased relative neutrophil numbers, although the DTH response was unchanged. Males (with 100 ppm Pb) had increased relative neutrophil numbers, decreased relative lymphocytes, and transiently increased nitrite production seen at 5, but not 13, wk of age. After gestational exposure to 50 ppm Pb, minimal immunotoxic effects were observed in either males or females at either developmental age assessed. These results suggest that differential gender-based immunotoxicity profiles exist after gestational Pb exposure depending on the concentration of Pb administered to the dam. In utero exposure of dams to 250 ppm Pb results in more profound immunotoxicity in females than males. Males arenot more sensitive to lower concentrations of Pb than females. Since the 50 ppm exposure produced minimal changes, these data may provide information to establish a no-observed-adverse-effect level (NOAEL) for in utero exposure to Pb. Additionally, while most effects were evident at both juvenile and adult ages, some changes were not fully evident until measured in the adult. Most changes were persistent with only one exception (male nitrite levels at 100 ppm).


Asunto(s)
Envejecimiento/inmunología , Inmunidad/efectos de los fármacos , Plomo/toxicidad , Envejecimiento/efectos de los fármacos , Animales , Formación de Anticuerpos/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Femenino , Hipersensibilidad Tardía , Masculino , Óxido Nítrico/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Ratas Endogámicas F344 , Caracteres Sexuales , Bazo/citología , Bazo/inmunología
17.
J Vet Diagn Invest ; 3(2): 127-32, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1892930

RESUMEN

Three biological properties of canine distemper virus were examined to determine if any would consistently differentiate field from vaccine strains of the virus. The properties were the ability to (1) infect macrophages and epithelial cells, (2) produce distinct cytopathologic effect in alveolar and peritoneal macrophages and Vero cells, and (3) produce pocks on the chorioallantoic membrane of embryonated chicken eggs. Four vaccine strains and 5 field isolates were used in the study. The 5 field isolates were obtained directly from canine tissues. Of the 3 properties studied, only the comparison of the ability of the viruses to infect macrophages and epithelial cells was a consistent marker of virus origin. Virulent field isolates would only infect macrophage cultures, whereas the vaccine strains infected both types of cells. One avirulent field isolate from a case of old dog encephalitis reacted more like a vaccine strain by infecting both cell types.


Asunto(s)
Virus del Moquillo Canino/patogenicidad , Macrófagos/microbiología , Vacunas Virales , Replicación Viral , Alantoides/microbiología , Animales , Línea Celular , Embrión de Pollo , Corion/microbiología , Efecto Citopatogénico Viral , Virus del Moquillo Canino/fisiología , Células Epiteliales , Epitelio/microbiología , Hurones , Técnica del Anticuerpo Fluorescente , Células Gigantes , Cavidad Peritoneal/citología , Alveolos Pulmonares/citología , Células Vero , Virulencia
18.
Hum Exp Toxicol ; 21(9-10): 479-85, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12458904

RESUMEN

While the history of immunotoxicology research involving experimental animals of immature ages dates back over several decades, there exist remarkably little data, to date, directly comparing the impact of developmental status on immunotoxicological risk. Given the size of the nonadult human population and the potential for differential vulnerability among the various ages, this represents a serious gap of knowledge in efforts to minimize environmentally linked health risks. This article frames the issues surrounding developmental immunotoxicological evaluations. In particular, the issues introduced include those of potential animal models, strain/genotype selection, gender, age of exposure, and age of assessment. Recent research results involving early exposure to lead (Pb) and other chemicals are discussed to highlight the nature of the decisions that are available and the potential cost-benefit associated with various approaches to evaluation.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Sustancias Peligrosas/toxicidad , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/crecimiento & desarrollo , Adolescente , Animales , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/prevención & control , Niño , Preescolar , Modelos Animales de Enfermedad , Hipersensibilidad a las Drogas/etiología , Hipersensibilidad a las Drogas/prevención & control , Exposición a Riesgos Ambientales/legislación & jurisprudencia , Guías como Asunto , Humanos , Lactante , Recién Nacido , Neoplasias/inducido químicamente , Neoplasias/prevención & control , Proyectos de Investigación , Medición de Riesgo , Pruebas de Toxicidad/normas , Toxicología/métodos , Toxicología/normas , Estados Unidos
19.
J Am Vet Med Assoc ; 167(9): 809-12, 1975 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-1237485

RESUMEN

Inactivated, nonadjuvanted tissue culture-origin rabies vaccine was tested in 168 dogs for its ability to provide protection against challenge of immunity 1 year after vaccination. Several laboratory methods were used concurrently to measure the potency of the vaccine. When used at full strength, the vaccine protected 70% of dogs after either a 1- or 2-dose vaccination schedule. When vaccine was diluted to contain less antigenic mass, the 1-dose schedule was not as effective as 2 doses. High serum-neutralizing antibody titers developed by 7 days after vaccination, but the titers declined rapidly thereafter. The US reference vaccine protected 28 of 30 dogs.


Asunto(s)
Enfermedades de los Perros/prevención & control , Vacunas Antirrábicas , Rabia/veterinaria , Animales , Enfermedades de los Perros/inmunología , Perros , Cobayas , Ratones , Rabia/inmunología , Rabia/prevención & control , Vacunas Antirrábicas/administración & dosificación , Virus de la Rabia/inmunología
20.
J Am Vet Med Assoc ; 183(9): 997-8, 965, 1983 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-12002593

RESUMEN

An adult male domestic short-hair cat developed posterior paralysis 22 days after being vaccinated for rabies with a high-egg-passage Flury strain vaccine currently approved for use in cats. A diagnosis of rabies was confirmed by mouse inoculations, and viral typing using a panel of monoclonal antibodies demonstrated that it was vaccine induced.


Asunto(s)
Enfermedades de los Gatos/etiología , Vacunas Antirrábicas/efectos adversos , Rabia/veterinaria , Animales , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/patología , Gatos , Resultado Fatal , Masculino , Ratones , Rabia/diagnóstico , Rabia/etiología , Rabia/patología , Virus de la Rabia/crecimiento & desarrollo , Virus de la Rabia/aislamiento & purificación
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