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1.
J Vet Emerg Crit Care (San Antonio) ; 27(2): 206-211, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28098944

RESUMEN

OBJECTIVE: To validate a smartphone-based spectrophotometric assay for point-of-care (POC) measurement of hemoglobin (Hgb) concentration against the standard measurement method in dogs without increases in serum lipemia, hemolysis, or bilirubin. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: One hundred thirty-nine dogs that had a CBC and corresponding biochemical profile submitted to the clinical pathology laboratory. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Blood tubes submitted for CBC were collected for hemoglobin (Hgb) measurements performed on a POC smartphone device. Each whole blood sample was run on the smartphone in duplicate using 2 strips, for a total of 4 POC Hgb readings per dog. Data collected for each dog included CBC Hgb value, 4 POC Hgb values, and select biochemistry values (bilirubin, lipemia, hemolysis, icterus). A calibration equation was estimated using a weighted linear regression: estimated CBC = (avgPOC-0.4871)/1.0015. For each dog, the percent error was computed between estimated and actual Hgb values; 95% of the percent errors ranged from -13.2% to 20.1%. The standard deviation of percent errors was 7.9% overall. When samples were further divided according to CBC Hgb concentration (low, normal or high), the standard deviation of percent error was 6.7% when Hgb<13 g/dL [130 g/L], 8.9% when Hgb 13-20 g/dL [130-200 g/L], and 6.5% when Hgb>20 g/dL [200 g/L]. The coefficient of variability among the 4 individual POC readings was 3.4%. CONCLUSIONS: A smartphone-based photometric method for measuring Hgb represents a clinically useful POC alternative to a standard laboratory Hgb measurement. There was excellent intrasample reproducibility, and the standard deviation of percent errors was relatively constant across CBC ranges. Additional sampling of patients with a greater range of diseases and biochemical abnormalities that may influence spectrophotometric assays (ie, abnormal bilirubin, icterus, lipemia, hemolysis) is warranted to extend the findings of this study.


Asunto(s)
Perros/sangre , Hemoglobinas/metabolismo , Sistemas de Atención de Punto , Teléfono Inteligente , Animales , Hemoglobinas/química , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados , Espectrofotometría
2.
Radiat Res ; 182(4): 396-407, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25211132

RESUMEN

Microdosimetric spectra of single event distributions have been used to provide estimates of quality factors for radiation protection of high-LET radiation. In situations with high-dose rates it becomes difficult to measure, record and store energy deposition from single events. An alternative approach is to store random energy deposition events in a sequence of fixed time intervals that does not require identifying from single events. This can be accomplished with a single detector without pulse height analysis. We show the development of the algorithm using expectation analysis of the statistical estimators for moments of lineal energy: ȳf and ȳD. The method was tested using Monte Carlo simulations based on single event distributions measured with spherical tissue equivalent proportional counters where the event sizes spanned more than two orders of magnitude. The evaluation included testing at various mean numbers of events per interval (i.e., dose rate) and numbers of intervals (i.e., total duration). Results of the expectation analysis and Monte Carlo simulation showed that the algorithm corrects for the excess dispersion due to the random number of events in each time interval when the underlying dose rate is constant. It also converges to the correct value when there is a linear trend in dose rate of the duration of the measurement process. Although this system is not applicable for pulsed radiation fields it proved to be robust when applied to measured distributions with single event spectra (PuBe neutrons, Fe ions at 1,000 MeV/nucleon and a power function distribution of single event sizes) with a coefficient of variation of 25% for estimates of ȳD using 100 sampling intervals and 10% using 400 sampling intervals.


Asunto(s)
Algoritmos , Transferencia Lineal de Energía , Radiometría/métodos , Absorción de Radiación , Método de Montecarlo
3.
Am J Vet Res ; 73(7): 1024-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22738054

RESUMEN

OBJECTIVE: To elucidate the species and biovariants of Pasteurellaceae isolated from clinically normal bighorn sheep (Ovis canadensis) or bighorn sheep with evidence of respiratory disease. SAMPLE: 675 Pasteurellaceae isolates from 290 free-ranging bighorn sheep in Idaho, Oregon and Wyoming. PROCEDURES: Nasal and oropharyngeal swab specimens were inoculated onto selective and nonselective blood agar media. Representatives of each colony type were classified via a biovariant scheme. The association of respective ß-hemolytic isolates with respiratory disease was evaluated via χ(2) analyses. RESULTS: Bacterial isolates belonged to 4 species: Histophilus somni, Mannheimia haemolytica, Pasteurella multocida, and Bibersteinia (Pasteurella) trehalosi. Within the latter 3 species, 112 subspecies, biotypes, and biovariants were identified. Bibersteinia trehalosi 2 and B trehalosi 2B constituted 345 of 675 (51%) isolates. Most (597/618 [97%]) isolates from adult sheep were from clinically normal animals, whereas most (47/57 [82%]) isolates from lambs were from animals with evidence of respiratory disease. Twenty-two Pasteurellaceae biovariants were isolated from sheep with respiratory disease; 17 of these biovariants were also isolated from clinically normal sheep. The ability of isolates to cause ß-hemolysis on blood agar was associated with respiratory disease in adult bighorn sheep (OR, 2.59; 95% confidence interval, 1.10 to 6.07). CONCLUSIONS AND CLINICAL RELEVANCE: Bighorn lambs appeared more susceptible to respiratory disease caused by Pasteurellaceae than did adult sheep. ß-Hemolytic Pasteurellaceae isolates were more likely to be associated with respiratory disease than were non-ß-hemolytic isolates in adult sheep. Identification of Pasteurellaceae with the greatest pathogenic potential will require studies to estimate the risk of disease from specific biovariants.


Asunto(s)
Infecciones por Pasteurellaceae/veterinaria , Pasteurellaceae/aislamiento & purificación , Enfermedades Respiratorias/veterinaria , Enfermedades de las Ovejas/microbiología , Animales , Distribución de Chi-Cuadrado , Femenino , Idaho/epidemiología , Masculino , Oregon/epidemiología , Pasteurellaceae/clasificación , Infecciones por Pasteurellaceae/epidemiología , Infecciones por Pasteurellaceae/microbiología , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/microbiología , Ovinos , Enfermedades de las Ovejas/epidemiología , Borrego Cimarrón , Wyoming/epidemiología
4.
PLoS One ; 7(12): e51994, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23300587

RESUMEN

Obesity increases risk for cardiomyopathy in the absence of hypertension, diabetes or ischemia. The fatty acid milieu, modulated by diet, may modify myocardial structure and function, lending partial explanation for the array of cardiomyopathic phenotypy. We sought to identify gross, cellular and ultrastructural myocardial changes associated with Western diet intake, and subsequent modification with docosahexaenoic acid (DHA) supplementation. Wistar and Sprague-Dawley (SD) rats received 1 of 3 diets: control (CON); Western (WES); Western + DHA (WES+DHA). After 12 weeks of treatment, echocardiography was performed and myocardial adiponectin, fatty acids, collagen, area occupied by lipid and myocytes, and ultrastructure were determined. Strain effects included higher serum adiponectin in Wistar rats, and differences in myocardial fatty acid composition. Diet effects were evident in that both WES and WES+DHA feeding were associated with similarly increased left ventricular (LV) diastolic cranial wall thickness (LVW(cr/d)) and decreased diastolic internal diameter (LVID(d)), compared to CON. Unexpectedly, WES+DHA feeding was associated additionally with increased thickness of the LV cranial wall during systole (LVW(cr/s)) and the caudal wall during diastole (LVW(ca/d)) compared to CON; this was observed concomitantly with increased serum and myocardial adiponectin. Diastolic dysfunction was present in WES+DHA rats compared to both WES and CON. Myocyte cross sectional area (CSA) was greater in WES compared to CON rats. In both fat-fed groups, transmission electron microscopy (TEM) revealed myofibril degeneration, disorganized mitochondrial cristae, lipid inclusions and vacuolation. In the absence of hypertension and whole body insulin resistance, WES+DHA intake was associated with more global LV thickening and with diastolic dysfunction, compared to WES feeding alone. Myocyte hypertrophy, possibly related to subcellular injury, is an early change that may contribute to gross hypertrophy. Strain differences in adipokines and myocardial fatty acid accretion may underlie heterogeneous data from rodent studies.


Asunto(s)
Cardiomiopatías/etiología , Dieta/efectos adversos , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Adiponectina/sangre , Animales , Western Blotting , Cardiomiopatías/metabolismo , Cardiomiopatías/prevención & control , Ecocardiografía , Ácidos Grasos/análisis , Leptina/sangre , Masculino , Microscopía Electrónica de Transmisión , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triglicéridos/sangre
5.
Vet Med Int ; 2011: 162520, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22195293

RESUMEN

Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents.

6.
Am J Trop Med Hyg ; 85(1): 3-5, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21734116

RESUMEN

Ivermectin mass drug administration (MDA) to humans is used to control onchocerciasis and lymphatic filariasis. Recent field studies have shown an added killing effect of ivermectin MDA against malaria vectors. We report that ivermectin MDA reduced the proportion of Plasmodium falciparum infectious Anopheles gambiae sensu stricto (s.s.) in treated villages in southeastern Senegal. Ivermectin MDA is a different delivery method and has a different mode of action from current malaria control agents. It could be a powerful and synergistic new tool to reduce malaria transmission in regions with epidemic or seasonal malaria transmission, and the prevalence and intensity of neglected tropical diseases.


Asunto(s)
Antimaláricos/administración & dosificación , Ivermectina/administración & dosificación , Malaria/tratamiento farmacológico , Humanos , Malaria/transmisión , Senegal
7.
Lipids Health Dis ; 10: 92, 2011 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-21649916

RESUMEN

BACKGROUND: Obesity increases the risk for development of cardiomyopathy in the absence of hypertension, diabetes or myocardial ischemia. Not all obese individuals, however, progress to heart failure. Indeed, obesity may provide protection from cardiovascular mortality in some populations. The fatty acid milieu, modulated by diet, may modify obesity-induced myocardial structure and function, lending partial explanation for the array of cardiomyopathic phenotype in obese individuals. METHODS: Adult male Sprague-Dawley rats were fed 1 of the following 4 diets for 32 weeks: control (CON); 50% saturated fat (SAT); 40% saturated fat + 10% linoleic acid (SAT+LA); 40% saturated fat + 10% α-linolenic acid (SAT+ALA). Serum leptin, insulin, glucose, free fatty acids and triglycerides were quantitated. In vivo cardiovascular outcomes included blood pressure, heart rate and echocardiographic measurements of structure and function. The rats were sacrificed and myocardium was processed for fatty acid analysis (TLC-GC), and evaluation of potential modifiers of myocardial structure including collagen (Masson's trichrome, hydroxyproline quantitation), lipid (Oil Red O, triglyceride quantitation) and myocyte cross sectional area. RESULTS: Rats fed SAT+LA and SAT+ALA diets had greater cranial LV wall thickness compared to rats fed CON and SAT diets, in the absence of hypertension or apparent insulin resistance. Treatment was not associated with changes in myocardial function. Myocardial collagen and triglycerides were similar among treatment groups; however, rats fed the high-fat diets, regardless of composition, demonstrated increased myocyte cross sectional area. CONCLUSIONS: Under conditions of high-fat feeding, replacement of 10% saturated fat with either LA or ALA is associated with thickening of the cranial LV wall, but without concomitant functional changes. Increased myocyte size appears to be a more likely contributor to early LV thickening in response to high-fat feeding. These findings suggest that myocyte hypertrophy may be an early change leading to gross LV hypertrophy in the hearts of "healthy" obese rats, in the absence of hypertension, diabetes and myocardial ischemia.


Asunto(s)
Grasas de la Dieta/farmacología , Ácidos Grasos/farmacología , Conducta Alimentaria/efectos de los fármacos , Miocardio/patología , Adiposidad/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Grasas de la Dieta/administración & dosificación , Ecocardiografía , Ácidos Grasos/administración & dosificación , Hemodinámica/efectos de los fármacos , Hidroxiprolina/metabolismo , Masculino , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Fosfolípidos/metabolismo , Ratas , Ratas Sprague-Dawley , Fracciones Subcelulares/efectos de los fármacos , Triglicéridos/metabolismo
8.
Vet Microbiol ; 150(3-4): 284-8, 2011 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-21345625

RESUMEN

A retrospective study of Pasteurellaceae isolated from domestic sheep (Ovis aries) was conducted. The aim was to identify Pasteurellaceae present in animals that were clinically healthy and others with evidence of respiratory disease. The bacteria had been isolated from samples submitted to the University of Idaho Caine Veterinary Teaching Center as part of disease diagnostic testing. The 844 isolates identified mainly three species of Pasteurellaceae: Mannheimia haemolytica, Pasteurella multocida, and Pasteurella (Bibersteinia) trehalosi. A total of 114 biovariants were identified among these three species. Individual biovariants were identified 1-180 times. Two of those (M. haemolytica 1 and P. (B.) trehalosi 2) constituted 36% of the isolates, and were the only biovariants sufficiently numerous to account for >7% of the total isolates. Samples were primarily submitted from sheep with signs of respiratory disease. Eighty percent of biovariants were identified most often in animals with signs of respiratory disease, but 26% of biovariants were isolated from both sheep with respiratory disease and apparently healthy sheep. P. multocida constituted 4.7% of isolates, and were exclusively associated with animals with respiratory disease. The ability of isolates to produce beta-hemolysis on culture media was not associated with animals with respiratory disease (odds ratio 0.77, 95% CI 0.50-1.19). The inference of this study is limited due to the retrospective study design. However, it is the first study that provides an extensive baseline list of biovariants associated with respiratory disease in domestic sheep.


Asunto(s)
Infecciones por Pasteurellaceae/veterinaria , Pasteurellaceae/aislamiento & purificación , Enfermedades de las Ovejas/microbiología , Oveja Doméstica , Animales , Mannheimia haemolytica/aislamiento & purificación , Pasteurellaceae/clasificación , Infecciones por Pasteurellaceae/microbiología , Estudios Retrospectivos , Ovinos
9.
Malar J ; 9: 365, 2010 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-21171970

RESUMEN

BACKGROUND: In south-eastern Senegal, malaria and onchocerciasis are co-endemic. Onchocerciasis in this region has been controlled by once or twice yearly mass drug administration (MDA) with ivermectin (IVM) for over fifteen years. Since laboratory-raised Anopheles gambiae s.s. are susceptible to ivermectin at concentrations found in human blood post-ingestion of IVM, it is plausible that a similar effect could be quantified in the field, and that IVM might have benefits as a malaria control tool. METHODS: In 2008 and 2009, wild-caught blood fed An. gambiae s.l. mosquitoes were collected from huts of three pairs of Senegalese villages before and after IVM MDAs. Mosquitoes were held in an insectary to assess their survival rate, subsequently identified to species, and their blood meals were identified. Differences in mosquito survival were statistically analysed using a Glimmix model. Lastly, changes in the daily probability of mosquito survivorship surrounding IVM MDAs were calculated, and these data were inserted into a previously developed, mosquito age-structured model of malaria transmission. RESULTS: Anopheles gambiae s.s. (P < 0.0001) and Anopheles arabiensis (P = 0.0191) from the treated villages had significantly reduced survival compared to those from control villages. Furthermore, An gambiae s.s. caught 1-6 days after MDA in treated villages had significantly reduced survival compared to control village collections (P = 0.0003), as well as those caught pre-MDA (P < 0.0001) and >7 days post-MDA (P < 0.0001). The daily probability of mosquito survival dropped >10% for the six days following MDA. The mosquito age-structured model of malaria transmission demonstrated that a single IVM MDA would reduce malaria transmission (Ro) below baseline for at least eleven days, and that repeated IVM MDAs would result in a sustained reduction in malaria Ro. CONCLUSIONS: Ivermectin MDA significantly reduced the survivorship of An. gambiae s.s. for six days past the date of the MDA, which is sufficient to temporarily reduce malaria transmission. Repeated IVM MDAs could be a novel and integrative malaria control tool in areas with seasonal transmission, and which would have simultaneous impacts on neglected tropical diseases in the same villages.


Asunto(s)
Anopheles/efectos de los fármacos , Antiprotozoarios/administración & dosificación , Vectores de Enfermedades , Insecticidas/administración & dosificación , Ivermectina/administración & dosificación , Oncocercosis/prevención & control , Animales , Humanos , Senegal , Análisis de Supervivencia
10.
Subst Use Misuse ; 45(1-2): 98-115, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20025441

RESUMEN

A sound decision regarding combination of datasets is critical for research validity. Data were collected between 1996 and 2000 via a 99-item survey of substance use behaviors. Two groups of 7th-12th grade students in predominately White communities are compared: 166,578 students from 193 communities with high survey participation and 41,259 students from 65 communities with lower participation. Hierarchical logistic models are used to explore whether the two datasets may be combined for further study of community-level substance use effects. "Scenario analysis" is introduced. Results suggest the datasets may reasonably be combined. Limitations and further research are discussed.


Asunto(s)
Participación de la Comunidad/estadística & datos numéricos , Recolección de Datos/estadística & datos numéricos , Modelos Logísticos , Trastornos Relacionados con Sustancias/psicología , Adolescente , Conducta del Adolescente , Encuestas Epidemiológicas , Humanos , Reproducibilidad de los Resultados
11.
J Androl ; 30(6): 642-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19443908

RESUMEN

UNLABELLED: We retrospectively mined and modeled data to answer 3 questions. 1) Relative to an estimate based on approximately 20 semen samples, how imprecise is an estimate of an individual's total sperm per ejaculate (TSperm) based on 1 sample? 2) What is the impact of abstinence interval on TSperm and TSperm/h? 3) How many samples are needed to provide a meaningful estimate of an individual's mean TSperm or TSperm/h? Data were for 18-20 consecutive masturbation samples from each of 48 semen donors. Modeling exploited the gamma distribution of values for TSperm and a unique approach to project to future samples. Answers: 1) Within-individual coefficients of variation were similar for TSperm or TSperm/h abstinence and ranged from 17% to 51%; average approximately 34%. TSperm or TSperm/h in any individual sample from a given donor was between -20% and +20% of the mean value in 48% of 18-20 samples per individual. 2) For a majority of individuals, TSperm increased in a nearly linear manner through approximately 72 hours of abstinence. TSperm and TSperm/h after 18-36 hours' abstinence are high. To obtain meaningful values for diagnostic purposes and maximize distinction of individuals with relatively low or high sperm production, the requested abstinence should be 42-54 hours with an upper limit of 64 hours. For individuals producing few sperm, 7 days or more of abstinence might be appropriate to obtain sperm for insemination. 3) At least 3 samples from a hypothetical future subject are recommended for most applications. Assuming 60 hours' abstinence, 80% confidence limits for TSperm/h for 1, 3, or 6 samples would be 70%-163%, 80%-130%, or 85%-120% of the mean for observed values. In only approximately 50% of cases would TSperm/h for a single sample be within -16% and +30% of the true mean value for that subject. CONCLUSIONS: Pooling values for TSperm in samples obtained after 18-36 or 72-168 hours' abstinence with values for TSperm obtained after 42-64 hours is inappropriate. Reliance on TSperm for a single sample per subject is unwise.


Asunto(s)
Eyaculación/fisiología , Semen/citología , Recuento de Espermatozoides/métodos , Espermatozoides , Humanos , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos , Abstinencia Sexual , Factores de Tiempo , Donantes de Tejidos
12.
Reprod Fertil Dev ; 20(1): 33-44, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18154696

RESUMEN

The present paper concerns statistical issues in the design of animal reproduction experiments, with emphasis on the problems of sample size determination and power calculations. We include examples and non-technical discussions aimed at helping researchers avoid serious errors that may invalidate or seriously impair the validity of conclusions from experiments. Screen shots from interactive power calculation programs and basic SAS power calculation programs are presented to aid in understanding statistical power and computing power in some common experimental situations. Practical issues that are common to most statistical design problems are briefly discussed. These include one-sided hypothesis tests, power level criteria, equality of within-group variances, transformations of response variables to achieve variance equality, optimal specification of treatment group sizes, 'post hoc' power analysis and arguments for the increased use of confidence intervals in place of hypothesis tests.


Asunto(s)
Reproducción , Proyectos de Investigación , Animales , Bovinos , Gonadotropina Coriónica/administración & dosificación , Femenino , Fructosa/análisis , Modelos Logísticos , Masculino , Modelos Biológicos , Modelos Estadísticos , Progesterona/sangre , Reproducibilidad de los Resultados , Tamaño de la Muestra , Semen/química , Temperatura
13.
Oecologia ; 153(2): 461-70, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17530293

RESUMEN

Movements of prey organisms across ecosystem boundaries often subsidize consumer populations in adjacent habitats. Human disturbances such as habitat degradation or non-native species invasions may alter the characteristics or fate of these prey subsidies, but few studies have measured the direct effects of this disruption on the growth and local abundance of predators in recipient habitats. Here we present evidence, obtained from a combined experimental and comparative study in northern Japan, that an invading stream fish usurped the flux of allochthonous prey to a native fish, consequently altering the diet and reducing the growth and abundance of the native species. A large-scale field experiment showed that excluding terrestrial invertebrates that fell into the stream with a mesh greenhouse reduced terrestrial prey in diets of native Dolly Varden charr (Salvelinus malma) by 46-70%, and reduced their growth by 25% over six weeks. However, when nonnative rainbow trout (Oncorhynchus mykiss) were introduced, they monopolized these prey and caused an even greater reduction of terrestrial prey in charr diets of 82-93%, and reduced charr growth by 31% over the same period. Adding both greenhouse and rainbow trout treatments together produced similar results to adding either alone. Results from a comparative field study of six other stream sites in the region corroborated the experimental findings, showing that at invaded sites rainbow trout usurped the terrestrial prey subsidy, causing a more than 75% decrease in the biomass of terrestrial invertebrates in Dolly Varden diets and forcing them to shift their foraging to insects on the stream bottom. Moreover, at sites with even low densities of rainbow trout, biomass of Dolly Varden was more than 75% lower than at sites without rainbow trout. Disruption of resource fluxes between habitats may be a common, but unidentified, consequence of invasions, and an additional mechanism contributing to the loss of native species.


Asunto(s)
Conducta Competitiva/fisiología , Dieta , Ecosistema , Invertebrados , Oncorhynchus mykiss/fisiología , Animales , Japón , Densidad de Población , Ríos , Factores de Tiempo , Trucha/crecimiento & desarrollo , Trucha/fisiología
14.
Am J Vet Res ; 68(1): 25-34, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17199415

RESUMEN

OBJECTIVE: To assess the pharmacokinetics and pharmacodynamics of morphine in llamas. ANIMALS: 6 healthy adult llamas. PROCEDURES: Llamas received morphine sulfate in a randomized crossover design. In phase 1, they received IV or IM administration of morphine at 0.05 or 0.5 mg/kg, respectively; in phase 2, they received IV administration of morphine at 0.05, 0.25, or 0.5 mg/kg. Plasma morphine and morphine-6-glucuronide concentrations were determined by validated methods. Body temperature, heart rate, respiratory rate, sedation, and analgesia were assessed and compared with plasma concentrations by regression analysis. RESULTS: Total body clearance was similar between IV administration of morphine sulfate at 0.25 and 0.5 mg/kg (mean +/- SD, 25.3 +/- 6.9 mL/min/kg and 27.3 +/- 5.9 mL/min/kg, respectively), and linearity was demonstrated between these doses. Bioavailability of morphine following IM administration at 0.5 mg/kg was 120 +/- 30%. Body temperature and sedation increased as the dose of morphine administered increased. Heart rate was unaffected by varying doses. Respiratory rate decreased as dose increased. Analgesia was difficult to assess as a result of high individual variability. Intravenous administration of morphine at 0.25 mg/kg provided the most consistent increase in tolerance to electric stimulation. Pharmacodynamic modeling revealed a sigmoidal relationship between plasma concentration and sedation score. CONCLUSIONS AND CLINICAL RELEVANCE: Morphine was characterized by a large apparent volume of distribution and high systemic clearance in llamas. A prolonged half-life was observed with IM injection. Intravenous administration of morphine sulfate at 0.25 mg/kg every 4 hours is suggested for further study.


Asunto(s)
Analgesia/veterinaria , Analgésicos Opioides/farmacocinética , Camélidos del Nuevo Mundo/metabolismo , Morfina/farmacocinética , Analgesia/métodos , Analgésicos Opioides/sangre , Analgésicos Opioides/farmacología , Animales , Temperatura Corporal/efectos de los fármacos , Camélidos del Nuevo Mundo/sangre , Estudios Cruzados , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Inyecciones Intramusculares/veterinaria , Inyecciones Intravenosas/veterinaria , Masculino , Morfina/sangre , Morfina/farmacología , Derivados de la Morfina/sangre , Distribución Aleatoria , Respiración/efectos de los fármacos
15.
J Am Vet Med Assoc ; 229(5): 711-6, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16948582

RESUMEN

OBJECTIVE: To compare recoveries from anesthesia of horses placed on a conventional padded stall floor or on a specially designed air pillow. DESIGN: Prospective study. ANIMALS: 409 horses (> 1 year old) that were anesthetized for surgical procedures during a 37-month period. PROCEDURES: By random allocation, horses were allowed to recover from anesthesia in either a foammat-padded recovery stall or an identical recovery stall equipped with a rapidly inflating-deflating air pillow. All recoveries were videotaped for subsequent analysis by an independent evaluator. Times to first movement, first attempt to attain sternal recumbency, attainment of sternal recumbency, first attempt to stand, and successful standing were recorded. The numbers of attempts before achieving sternal recumbency and standing were counted, and scores for quality of standing and overall recovery were assigned. Recovery-related variables were compared between groups. RESULTS: Compared with horses allowed to recover in a conventional manner, horses that recovered from anesthesia on the air pillow had a significantly longer rest period before attempting to attain sternal recumbency and rise to standing. Once the pillow was deflated, horses were able to stand after significantly fewer attempts and the quality of their standing was significantly better. Between the 2 groups of horses, there was no significant difference in overall recovery quality scores. The air pillow and padded floor systems were equally safe. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that use of a rapidly inflating-deflating air pillow promotes a longer period of recumbency and a better quality of standing after anesthesia in horses.


Asunto(s)
Periodo de Recuperación de la Anestesia , Anestesia/veterinaria , Caballos/fisiología , Vivienda para Animales/normas , Animales , Caballos/cirugía , Estudios Prospectivos , Distribución Aleatoria
16.
J Am Vet Med Assoc ; 226(6): 904-8, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15786991

RESUMEN

OBJECTIVE: To evaluate a method of aerobic bacteriologic culture of epidermal collarette specimens from dogs with superficial pyoderma and compare results with those for aerobic bacteriologic culture of abdominal skin specimens in healthy dogs. DESIGN: Prospective study. ANIMALS: 22 dogs with epidermal collarettes and 24 healthy dogs. PROCEDURE: Dry sterile cotton swabs were rolled across epidermal collarettes or hairless areas of abdominal skin in healthy dogs and submitted for aerobic bacteriologic culture. Hemolytic colonies of gram-positive-staining cocci were tested for catalase production, and if results were positive, a coagulase test was performed. Colonies with coagulase activity were tested for the ability to ferment mannitol. Antimicrobial susceptibility testing was performed on all Staphylococcus spp that were isolated. RESULTS: S. intermedius was isolated from collarettes in 18 of 22 dogs with superficial pyoderma but not from healthy dogs. Estimated sensitivity and specificity of the culture method were 81.8% and 100%, respectively. There were no significant differences in the ability to culture S. intermedius, the number of S. intermedius isolates without resistance to antimicrobials, and the number of S. intermedius isolates resistant to penicillin G when comparing dogs with superficial pyoderma for the first time and dogs with recurrent pyoderma, dogs that did or did not receive concurrent antimicrobials, and dogs with and without underlying allergic disease. CONCLUSIONS AND CLINICAL RELEVANCE: Bacteriologic culture of epidermal collarette specimens was a simple and reliable method for identification of S. intermedius in dogs with superficial pyoderma, regardless of history of pyoderma or current antimicrobial use.


Asunto(s)
Antibacterianos/farmacología , Enfermedades de los Perros/microbiología , Piodermia/veterinaria , Infecciones Cutáneas Estafilocócicas/veterinaria , Staphylococcus/efectos de los fármacos , Staphylococcus/aislamiento & purificación , Animales , Estudios de Casos y Controles , Catalasa/metabolismo , Enfermedades de los Perros/tratamiento farmacológico , Perros , Femenino , Masculino , Pruebas de Sensibilidad Microbiana/veterinaria , Estudios Prospectivos , Piodermia/tratamiento farmacológico , Piodermia/microbiología , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Infecciones Cutáneas Estafilocócicas/microbiología , Staphylococcus/enzimología
17.
Epilepsia ; 46(1): 8-14, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15660763

RESUMEN

PURPOSE: Potential antiepileptic drugs (AEDs) are typically screened on acute seizures in normal animals, such as those induced in the maximal electroshock and pentylenetet-razole models. As a proof-of-principle test, the present experiments used spontaneous epileptic seizures in kainate-treated rats to examine the efficacy of topiramate (TPM) with a repeated-measures, crossover protocol. METHODS: Kainic acid was administered in repeated low doses (5 mg/kg) every hour until each Sprague-Dawley rat experienced convulsive status epilepticus for >3 h. Six 1-month trials (n = 6-10 rats) assessed the effects of 0.3-100 mg/kg TPM on spontaneous seizures. Each trial involved six pairs of TPM and saline-control treatments administered as intraperitoneal injections on alternate days with a recovery day between each treatment day. Data analysis included a log transformation to compensate for the asymmetric distribution of values and the heterogeneous variances, which appeared to arise from clustering of seizures. RESULTS: A significant effect of TPM was observed for 12 h (i.e., two 6-h periods) after a 30-mg/kg injection, and full recovery from the drug effect was complete within 43 h. TPM exerted a significant effect at doses of 10, 30, and 100 mg/kg, and the effects of TPM (0.3-100 mg/kg) were dose dependent. CONCLUSIONS: These data suggest that animal models with spontaneous seizures, such as kainate- and pilocarpine-treated rats, can be used efficiently for rapid testing of AEDs with a repeated-measures, crossover protocol. Furthermore, the results indicate that this design allows both dose-effect and time-course-of-recovery studies.


Asunto(s)
Anticonvulsivantes/farmacología , Modelos Animales de Enfermedad , Epilepsia/prevención & control , Fructosa/análogos & derivados , Fructosa/farmacología , Ácido Kaínico , Animales , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/uso terapéutico , Enfermedad Crónica , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/estadística & datos numéricos , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Fructosa/administración & dosificación , Fructosa/uso terapéutico , Inyecciones Intraperitoneales , Pilocarpina , Ratas , Ratas Sprague-Dawley , Proyectos de Investigación/normas , Cloruro de Sodio/farmacología , Estado Epiléptico/inducido químicamente , Estado Epiléptico/tratamiento farmacológico , Estado Epiléptico/prevención & control , Topiramato
18.
Tuberculosis (Edinb) ; 84(6): 361-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15525559

RESUMEN

The Cornell model has been extensively used as a mouse model for studying the latent stage of Mycobacterium tuberculosis infection. In this model mice are infected and then given a course of chemotherapy prior to reactivation of infection. We discuss here the importance of using adequate mouse numbers in a Cornell model for the study of relapse rates in order to obtain sufficient statistical power to confirm a hypothesis. Experiments with small sample sizes are useful for 'screening' experiments, but will have very little value in 'confirming' the objective. When the objective of the experiment is confirmation of an effect through establishment of statistical significance, power calculations are critical in order to assure that the sample size will be sufficient to meet that objective.


Asunto(s)
Modelos Animales de Enfermedad , Tuberculosis Pulmonar , Animales , Ratones , Ratones Endogámicos , Recurrencia , Tamaño de la Muestra
19.
Vet Dermatol ; 15(4): 207-17, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15305927

RESUMEN

Data on fifty horses with hereditary equine regional dermal asthenia (HERDA; "hyperelastosis cutis") were collected on clinical, histopathological, ultrastructural and immunohistological findings. All horses were Quarter horses or of Quarter horse ancestry. Pedigree evaluation strongly supported an autosomal recessive mode of inheritance. The most common lesions were seromas/haematomas, open wounds, sloughing skin, and loose, easily tented skin that did not return to its initial position. Definitive diagnosis could not be made via histopathology, although the presence of tightly grouped thin and shortened collagen fibres arranged in clusters in the deep dermis was suggestive of the disease. Trichrome, acid orcein-Giemsa and immunohistochemical stains for collagens I and III showed no consistent abnormalities compared to control horses; an increase in elastic fibres was not a consistent finding. Electron microscopy showed no abnormalities in the periodicity of the collagen bundles; neither orientation nor variation of cross-section diameter of the collagen fibrils differentiated control from affected horses. The diagnosis of HERDA relies on clinical presentation, but may be supported by suggestive (although not pathognomonic) histopathological lesions.


Asunto(s)
Síndrome de Ehlers-Danlos/veterinaria , Enfermedades de los Caballos/diagnóstico , Animales , Estudios de Cohortes , Diagnóstico Diferencial , Síndrome de Ehlers-Danlos/diagnóstico , Femenino , Predisposición Genética a la Enfermedad , Enfermedades de los Caballos/genética , Enfermedades de los Caballos/patología , Caballos , Inmunohistoquímica/veterinaria , Masculino , Linaje , Estudios Prospectivos , Estudios Retrospectivos , Piel/patología , Piel/ultraestructura
20.
Mil Med ; 168(5): 373-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12775172

RESUMEN

Thirty-nine U.S. Air Force enlisted men participated in a randomized controlled study that evaluated an experimental program designed to enhance fitness. Subjects were assigned to either a treatment (access to the program) or control (no access to program) group for 6 months. To improve treatment group fitness (as measured by VO2, subjects received individually tailored information (based on a behavior change model) via the Internet to encourage adoption of positive diet and exercise behaviors. Results showed no significant effect in improving fitness in treatment. However, significant effects were observed for secondary outcomes such as weight (controls, +1.0 kg vs. treatment, -2.2 kg, p < 0.05), body mass index (+0.3 kg/m2 vs. -0.7 kg/m2, p < 0.05), and percent body fat (+0.6% vs. -1.5%, p < 0.001). The data suggest that the individually tailored exercise information was not effective in encouraging sufficient exercise intensity to impact fitness. However, the dietary tailored information appears to have encouraged the adoption of more positive nutritional practices as demonstrated by the beneficial effects reflected in secondary outcomes.


Asunto(s)
Ejercicio Físico , Conductas Relacionadas con la Salud , Educación en Salud/métodos , Personal Militar , Fenómenos Fisiológicos de la Nutrición , Adulto , Análisis de Varianza , Humanos , Internet , Masculino , Modelos Teóricos , Aptitud Física , Evaluación de Programas y Proyectos de Salud , Resultado del Tratamiento
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