RESUMEN
Water temperatures that exceed thermal optimal ranges (~19 to 22°C for greenlip abalone Haliotis laevigata, depending on stock genetics) can be associated with abalone mortalities. We assessed histopathological changes in H. laevigata gills held in control (22°C) or elevated (25°C) water temperature conditions for 47 d by developing a new scoring protocol that incorporates histopathological descriptions and relative score summary. Lesions were allocated to 1 of 3 reaction patterns, (1) epithelial, (2) circulatory or (3) inflammatory, and scored based on their prevalence in gill leaflets. Indices for each reaction pattern were calculated and combined to provide an overall gill index. H. laevigata held in 25°C water temperature had significantly more epithelial lifting and hemolymph channel enlargement and significantly higher gill and circulatory reaction pattern indices than H. laevigata held in 22°C water temperature. One H. laevigata had a proliferation of unidentified cells in the v-shaped skeletal rod of a gill leaflet. The unidentified cells contained enlarged nuclei, a greater nucleus:cytoplasm ratio and, in some cases, mitotic figures. This cell population could represent a region of hematopoiesis in response to hemocyte loss or migration to a lesion. Without thorough diagnostic testing, the origin of these larger cells cannot be confirmed. The new scoring protocol developed will allow the standard quantification of gill lesions for H. laevigata, specifically for heat-related conditions, and could further be adapted for other Haliotis spp.
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Gastrópodos , Branquias , Animales , Calor , Temperatura , AguaRESUMEN
The muscle and liver fatty acid composition of young-of-the-year (YOY) Port Jackson sharks Heterodontus portusjacksoni were investigated to determine the effects of a known dietary lipid source v. maternal input as demonstrated by egg yolk fatty acid profiles. Ten Heterodontus portusjacksoni egg yolks were collected in situ and compared with four hatched H. portusjacksoni fed a known diet in a controlled feeding experiment of 185 days. This study demonstrated that fatty acids are probably conservatively transferred from egg yolks to YOY H. portusjacksoni, while diet did not have a large effect on the fatty acid composition of the liver or muscle.
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Ácidos Grasos/química , Tiburones/fisiología , Animales , Dieta , Yema de Huevo/química , Grasas/química , Hígado/química , Músculos/químicaRESUMEN
The summer of 2003 was probably the hottest in Europe since at latest ad 1500, and unusually large numbers of heat-related deaths were reported in France, Germany and Italy. It is an ill-posed question whether the 2003 heatwave was caused, in a simple deterministic sense, by a modification of the external influences on climate--for example, increasing concentrations of greenhouse gases in the atmosphere--because almost any such weather event might have occurred by chance in an unmodified climate. However, it is possible to estimate by how much human activities may have increased the risk of the occurrence of such a heatwave. Here we use this conceptual framework to estimate the contribution of human-induced increases in atmospheric concentrations of greenhouse gases and other pollutants to the risk of the occurrence of unusually high mean summer temperatures throughout a large region of continental Europe. Using a threshold for mean summer temperature that was exceeded in 2003, but in no other year since the start of the instrumental record in 1851, we estimate it is very likely (confidence level >90%) that human influence has at least doubled the risk of a heatwave exceeding this threshold magnitude.
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Efecto Invernadero , Calor , Actividades Humanas , Estaciones del Año , Tiempo (Meteorología) , Contaminación del Aire , Atmósfera/química , Europa (Continente)/epidemiología , Humanos , Funciones de Verosimilitud , Modelos Teóricos , Mortalidad , Riesgo , Factores de TiempoRESUMEN
The addition of fiber in chick feeds is known to dilute nutrients; as a result, this may reduce nutrient digestibility and performance. However, recent studies suggest that moderate inclusion of insoluble fibers (2 to 3%) may stimulate gizzard development, which could result in better nutrient utilization and chick growth. The previous fiber sources evaluated were subject to wide fluctuation in their nutritional and chemical composition due to variation in processing. Miscanthus giganteus is a C4 grass purposefully grown for its fiber content which has a consistent fiber composition compared to food process residues. The objectives of this study were to determine the effect of dietary fiber source and particle size on day-old chick performance and nutrient digestibility. Day-old chicks (8 chicks per cage, 5 cages per treatment) were fed diets containing 3% of either sepiolite (SEP), cellulose (CEL), coarse beet pulp (BP), fine BP, coarse Miscanthus grass (MG), and fine MG. At the end of days 7, 14, and 21, chicks and experimental diets were weighed to compute average daily gain and feed intake. In addition, excreta from the previous 48 h of each data capture point was collected to determine nutrient digestibility. In general, chicks fed diets containing fiber consumed more feed, gained more weight, and had better feed conversion rate than birds fed the SEP diet. Particle size of the fiber had no effect on chick performance; however, nutrient utilization was higher (P < 0.05) for chicks fed coarse fiber particles compared to these fed fine fiber particles. Birds fed diets containing MG performed similar to chicks fed CEL (P > 0.05), but digestibility coefficients of birds fed BP diets were generally higher than chicks fed MG diets. In conclusion, chicks performed better with fiber in their diet and MG was comparable to CEL.
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Pollos/fisiología , Fibras de la Dieta/metabolismo , Digestión/efectos de los fármacos , Nutrientes/fisiología , Tamaño de la Partícula , Poaceae/química , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Beta vulgaris/química , Celulosa/administración & dosificación , Celulosa/metabolismo , Dieta/veterinaria , Fibras de la Dieta/administración & dosificación , Fibras de la Dieta/clasificación , Silicatos de Magnesio/administración & dosificación , Silicatos de Magnesio/metabolismo , Masculino , Distribución AleatoriaRESUMEN
The paper presents a review of the current ability of the climate modelling community to produce predictions of future climate change. Predictions for the next few decades are reasonably robust, whereas predictions for later time periods depend on uncertainties in climate model structure and on the unknown future course of greenhouse gas emissions. Some regional features are noticeable; however, meaningful interpretation of these can only presently be made at spatial scales that are considerably larger than those required for making sound estimates of the effects of future climate change on animal health. The implication is that current climate change predictions should be considered indicative rather than accurate.
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Enfermedades de los Animales/epidemiología , Clima , Desastres , Efecto Invernadero , Modelos Teóricos , Enfermedades de los Animales/prevención & control , Animales , Simulación por Computador , Predicción , Humanos , Valor Predictivo de las Pruebas , Lluvia , Temperatura , Factores de TiempoRESUMEN
Poly(hydroxyalkanoates) are natural polymers with thermoplastic properties. One polymer of this class with commercial applicability, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) can be produced by bacterial fermentation, but the process is not economically competitive with polymer production from petrochemicals. Poly(hydroxyalkanoate) production in green plants promises much lower costs, but producing copolymer with the appropriate monomer composition is problematic. In this study, we have engineered Arabidopsis and Brassica to produce PHBV in leaves and seeds, respectively, by redirecting the metabolic flow of intermediates from fatty acid and amino acid biosynthesis. We present a pathway for the biosynthesis of PHBV in plant plastids, and also report copolymer production, metabolic intermediate analyses, and pathway dynamics.
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Arabidopsis/metabolismo , Brassica/metabolismo , Poliésteres/metabolismo , Acilcoenzima A/biosíntesis , Aminación , Butiratos/metabolismo , Espectroscopía de Resonancia MagnéticaRESUMEN
PURPOSE: To increase the taxol dose beyond the current standard dose intensity of 175 mg/m2 per 21 days in patients with refractory ovarian cancer. PATIENTS AND METHODS: Fifteen patients who had platinum-refractory or recurrent advanced-stage ovarian cancer were treated with taxol in a phase I trial and were given granulocyte-colony stimulating factor (G-CSF). Taxol was administered at doses of 170, 200, 250, and 300 mg/m2 every 3 weeks. G-CSF was given as a daily subcutaneous injection that started 24 hours after the completion of the taxol infusion. RESULTS: Four patients required either taxol dose reduction or delay. The dose-limiting toxicity (DLT) was peripheral neuropathy, and it occurred at 300 mg/m2. This toxicity was manifested clinically as a stocking-and-glove sensory disturbance that primarily affected proprioception, and was associated with objective changes on nerve conduction studies in affected individuals. Mucositis was rarely observed. Substantial myelosuppression was observed, but was not dose-limiting. Five of 14 assessable patients experienced an objective response to therapy, with another five individuals who experienced a 30% to 45% reduction in tumor mass. CONCLUSION: Taxol can be safely administered in doses up to 250 mg/m2 with G-CSF support, which may make it possible to study taxol dose intensification.
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Alcaloides/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Enfermedades de la Médula Ósea/prevención & control , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Adulto , Anciano , Alcaloides/efectos adversos , Antineoplásicos Fitogénicos/efectos adversos , Enfermedades de la Médula Ósea/inducido químicamente , Carcinoma/tratamiento farmacológico , Evaluación de Medicamentos , Femenino , Humanos , Persona de Mediana Edad , Paclitaxel , Resultado del TratamientoRESUMEN
Compressive neuropathy due to tight application of handcuffs occurred in 5 patients. The superficial radial nerve was affected in 8 hands and the median nerve in two. Neurologic deficits persisted as long as 3 years after handcuffing. Nerve conduction studies helped to exclude malingering and other diagnoses. All patients had been intoxicated when handcuffed or had been arrested with force. The handcuff mechanism, which allows accidental overtightening after application, is an unrecognized factor in these neuropathies.
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Crimen , Traumatismos de los Nervios Periféricos , Adulto , Electromiografía , Humanos , Masculino , Nervio Mediano/lesiones , Persona de Mediana Edad , Conducción Nerviosa , Parestesia/etiología , Nervios Periféricos/fisiopatología , Nervio Radial/lesiones , Sensación , Muñeca/inervaciónRESUMEN
Although the placebo in a clinical trial is often considered simply a baseline against which to evaluate the efficacy of a clinical intervention, there is evidence that the magnitude of placebo effect may be a critical factor in determining the results of a trial. This article examines the question of whether devices have enhanced placebo effects and, if so, what the implications may be. While the evidence of an enhanced placebo effect remains rudimentary, it is provocative and therefore worthy of further study. Suggestions are made, therefore, for how such an effect can be investigated without violating the principles of informed consent.
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Ensayos Clínicos como Asunto , Equipos y Suministros , Efecto Placebo , Proyectos de Investigación , HumanosRESUMEN
To decrease adolescent morbidity and mortality and improve the quality of life, a violence-prevention consultation is offered to hospitalized victims of nondomestic violence. The context is a violence-prevention team approach to patient assessment, treatment, and follow-up. Psychoeducational counseling emphasizes the individual through a cognitive behavioral approach and also recognizes the individual in the proximal social setting through referrals to community resources. The in-hospital component draws on the health beliefs model, self-efficacy, the theory of reasoned action and their synergy with cognitive mediation theory as expressed in developmental psychology. The target group for the intervention is adolescents (12-17 years of age) who have been victims of violent assaults severe enough to warrant treatment at a Level One trauma center. The six steps in the intervention are to (1) review and assess the incident, (2) review the patient's conflict-resolution strategies and introduce nonviolent alternatives, (3) provide information on the prevalence of violence/homicide and determine the patient's risk status, (4) explore the patient's coping skills and support system, (5) develop a plan to stay safe, and (6) refer patient to services for follow-up activities. Approximately 15 study participants are identified each month, half of whom are randomly assigned to receive the intervention. Over the 12-month recruitment interval, approximately 180 adolescent patients will be identified. Baseline data are collected through hospital intake procedures and chart reviews. A battery of standardized measures supplemented by a brief structured, closed-ended interview is collected four months after the youths leave the hospital. Preliminary baseline data for 39 youths are reported. The "typical" youth is a 16-year-old African-American male. Even though nearly one third of victims had been shot, the typical patient was injured in a fight during which he was kicked, bitten, or beaten with or without a blunt instrument. The majority of incidents involved only one attacker who was known to the victim. Nearly half the injuries were precipitated by an argument or fight. No statistically significant differences between intervention subjects and nonintervention controls in terms of baseline variables have been observed. For inner-city adolescent victims of violent assaults, a hospital-based intervention offers a unique opportunity for reduction of the incidence of reinjury. We describe the elements of the intervention, including the theoretical basis and implementation; detail the overall evaluation design including modifications; and present preliminary analyses of baseline data.
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Adolescente Hospitalizado/estadística & datos numéricos , Víctimas de Crimen/estadística & datos numéricos , Cuidados Críticos/métodos , Grupo de Atención al Paciente/organización & administración , Violencia/estadística & datos numéricos , Adolescente , Niño , Consejo/métodos , Femenino , Humanos , Masculino , Massachusetts , Educación del Paciente como Asunto/métodos , Estudios Prospectivos , Distribución Aleatoria , Derivación y Consulta , Violencia/prevención & controlRESUMEN
Hydrazine fuels are used as examples of the relatively rapid chemical processes which may occur when propellants are released into the atmosphere from normal handling or during accidents. The experimental procedures used to study these processes are reviewed along with postulated chemical reaction mechanisms and measured reaction rates and products. Results show that chemical processes which occur on a time scale comparable with meteorological processes must be considered in the development of dispersion models. These models must also account for the potential formation of toxic reaction products.
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Contaminantes Atmosféricos/toxicidad , Atmósfera , Aviación , Monitoreo del Ambiente/normas , Fenómenos Químicos , Química , Aceites Combustibles , Hidrazinas/toxicidadRESUMEN
Previous studies using thallium-201 scintigraphy have suggested that angiographic coronary collaterals can protect against the development of stress-induced perfusion abnormalities, but the effect of collaterals on stress echocardiography (SECHO) has not been determined. In this study, 21 consecutive patients referred for cardiac catheterization underwent SECHO and coronary angiography. Of the 21 study patients, there was a total of 16 significantly obstructed coronary arteries (> or = 70% stenosis) in 14 patients. SECHO revealed stress-induced wall motion abnormalities in the distribution of seven of nine obstructed coronary vessels without angiographic collaterals, but in only one of seven vessels with collaterals (p < 0.05). Six of eight obstructed vessels not associated with a stress-induced wall motion abnormality had collaterals, whereas only one of eight obstructed vessels associated with a stress-induced wall motion abnormality had collaterals. We conclude that (1) angiographically demonstrated coronary collaterals can protect against the development of stress-induced wall motion abnormalities despite the presence of a high-grade coronary artery obstruction, and (2) the lack of a stress-induced wall motion abnormality on SECHO in the perfusion territory of an obstructed vessel may suggest the presence of adequate collateral perfusion.
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Circulación Colateral , Angiografía Coronaria , Circulación Coronaria , Enfermedad Coronaria/fisiopatología , Prueba de Esfuerzo , Anciano , Constricción Patológica , Enfermedad Coronaria/diagnóstico por imagen , Dobutamina , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Previous studies have demonstrated that pharmacologic stress thallium-201 (201Tl) myocardial scintigraphy is a useful tool to evaluate preoperative cardiac risk. HYPOTHESIS: The purpose of this study was to assess the utility of adenosine stress dual-isotope [rest 201Tl/stress technetium-99m (99mTc) sestamibi] myocardial single-photon emission computed tomography (SPECT) in predicting the risk of perioperative cardiac events (unstable angina, myocardial infarction, cardiac death) in patients undergoing major noncardiac surgery. METHODS: We evaluated 43 consecutive patients (20 men, 23 women, mean age 64 years, range 30-83 years) within 8 weeks prior to major noncardiac surgery requiring general anesthesia. SPECT imaging was performed with 111 MBq (3 mCi) 201Tl at rest and 925 MBq (25 mCi)99mTc sestamibi during adenosine stress. RESULTS: Of the 43 patients, 15 (35%) had stress-induced ischemia and 28 (65%) did not. Perioperative cardiac events occurred in 4 (27%) of the 15 patients with stress-induced ischemia (2 unstable angina, 2 nonfatal myocardial infarctions) and in none of the 28 patients without inducible ischemia (p = 0.02). CONCLUSION: Adenosine stress dual-isotope myocardial SPECT is useful in determining the preoperative cardiac risk of patients undergoing major noncardiac surgery.
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Adenosina , Cardiomiopatías/diagnóstico por imagen , Fármacos Cardiovasculares , Corazón/diagnóstico por imagen , Tecnecio Tc 99m Sestamibi , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Anciano de 80 o más Años , Cardiomiopatías/fisiopatología , Cardiomiopatías/prevención & control , Prueba de Esfuerzo/métodos , Femenino , Estudios de Seguimiento , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Retrospectivos , Medición de Riesgo , Factores de RiesgoRESUMEN
The genes encoding the polyhydroxyalkanoate (PHA) biosynthetic pathway in Ralstonia eutropha (3-ketothiolase, phaA or bktB; acetoacetyl-CoA reductase, phaB; and PHA synthase, phaC) were engineered for plant plastid targeting and expressed using leaf (e35S) or seed-specific (7s or lesquerella hydroxylase) promoters in Arabidopsis and Brassica. PHA yields in homozygous transformants were 12-13% of the dry mass in homozygous Arabidopsis plants and approximately 7% of the seed weight in seeds from heterozygous canola plants. When a threonine deaminase was expressed in addition to bktB, phaB and phaC, a copolyester of 3-hydroxybutyrate and 3-hydroxyvalerate was produced in both Arabidopsis and Brassica.
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Acetil-CoA C-Aciltransferasa/metabolismo , Aciltransferasas/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Arabidopsis/metabolismo , Cupriavidus necator/enzimología , Poliésteres/metabolismo , Acetil-CoA C-Aciltransferasa/genética , Aciltransferasas/genética , Oxidorreductasas de Alcohol/genética , Arabidopsis/genética , Cupriavidus necator/genética , Homocigoto , Modelos Moleculares , Estructura Molecular , Hojas de la Planta , Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Recombinantes/metabolismo , SemillasRESUMEN
Effective treatment of the female athlete begins with an understanding of the anatomic and physiologic differences between males and females and the epidemiology of injury patterns in athletic women. However, the female athlete has a variety of special concerns that the sports medicine physician should be familiar with.
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Deportes/fisiología , Adolescente , Adulto , Traumatismos en Atletas/epidemiología , Composición Corporal , Mama/fisiología , Anticonceptivos Orales/farmacología , Ejercicio Físico/fisiología , Trastornos de Alimentación y de la Ingestión de Alimentos/fisiopatología , Femenino , Humanos , Ciclo Menstrual/fisiología , Músculos/fisiología , Factores Sexuales , Somatotipos/fisiologíaRESUMEN
The recent use of 70% hydrazine-water fuel in the F-16 emergency power unit (EPU) presents problems for organizations responsible for protection of personnel and the environment because of the worldwide deployment of this aircraft and the requirement for fuel handling in a flightline environment. Hydrazine has a low vapor pressure (14 mm Hg at 25 degrees C) but still evaporation rates (16-100 mg/cm2h) from liquid pools are sufficient to generate hazardous atmospheric concentrations greater than the permissible exposure level (3 ppm) up to 2 km downwind under worst-case meteorological conditions (F Stability). In contrast to the general feeling that hydrazine degrades in the presence of atmospheric oxygen, studies show hydrazine is relatively stable in both air (t1/2 approximately 6 h) and oxygenated aqueous solutions (t1/2 approximately 5 d). The toxicity and stable character of hydrazine in the environment required quick and thorough management of any accidental spills to preclude hazards to personnel and serious environmental degradation. The Air Force has established comprehensive containment and treatment procedures which will be used in the event of inadvertent releases of hydrazine from the EPU or during handling or transport of the bulk fuel. The simple spill management procedures used to support the F-16 aircraft EPU are described.
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Aeronaves , Descontaminación/métodos , Combustibles Fósiles , Conceptos Meteorológicos , AccidentesRESUMEN
The medical records of 192 women with nonpalpable mammographically detected breast lesions who underwent needle-localized breast biopsy between January 1989 and January 1991 and between March 1992 and March 1994 were reviewed. Of the 192 patients examined, 100 underwent biopsy for evaluation of microcalcifications suggestive of malignancy. Ninety-two biopsies were performed for non-specific radiodensities not inclusive of microcalcifications. This study examines the radiographic characteristics of the nonpalpable breast lesion. Although presence of microcalcifications on mammograms are an important finding in detection of breast carcinoma, it must not be considered pathognomonic. Other distinguishing factors require evaluation to assess the indication for biopsy. Central to this study was the presence of microcalcifications alone or as detected in association with a dominant mass. Cancer was discriminated in 38 (20%) of the patients studied. Mammographic findings with microcalcification, regardless of the presence of a mass, were found to be malignant in 20% of patients undergoing biopsy. Nine percent of biopsies done to evaluate microcalcifications alone were malignant. The finding of microcalcification associated with a dominant mass proved malignant in 34% of patients who had a biopsy done. The authors include guidelines for increasing the effectiveness of needle-localized biopsies of the breast.
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Biopsia con Aguja/métodos , Neoplasias de la Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Incidencia , Mamografía , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
The many purposes of this article is to understand the role and value of case management from the perspective of program directors, case managers and clients. A survey of program directors from publicly funded substance abuse treatment programs in Boston was administered, and in-depth interviews with a sample of program directors, case managers, and clients were conducted. Case management allowed programs to serve more complex clients and increased time available for counselors to focus on the clinical needs of clients. From the perspective of case managers and clients, much of the value of case management came from educating clients about steps they could take to meet their needs and then supporting them in their efforts as they took these steps. Successful steps taken to deal with these needs helped lay the foundation necessary to confront the challenges of treatment. Program directors, case managers, and clients considered case management a valuable enhancement to substance abuse treatment.