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1.
Mediators Inflamm ; 2020: 6245798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189995

RESUMO

Rheumatoid arthritis is characterised by a chronic inflammatory response resulting in destruction of the joint and significant pain. Although a range of treatments are available to control disease activity in RA, bone destruction and joint pain exist despite suppression of inflammation. This study is aimed at assessing the effects of parthenolide (PAR) on paw inflammation, bone destruction, and pain-like behaviour in a mild collagen antibody-induced arthritis (CAIA) mouse model. CAIA was induced in BALB/c mice and treated daily with 1 mg/kg or 4 mg/kg PAR. Clinical paw inflammation was scored daily, and mechanical hypersensitivity was assessed on alternate days. At end point, bone volume and swelling in the paws were assessed using micro-CT. Paw tissue sections were assessed for inflammation and pre-/osteoclast-like cells. The lumbar spinal cord and the periaqueductal grey (PAG) and rostral ventromedulla (RVM) regions of the brain were stained for glial fibrillary acidic protein (GFAP) and ionised calcium-binding adaptor molecule 1 (IBA1) to assess for glial reactivity. Paw scores increased in CAIA mice from days 5-10 and were reduced with 1 mg/kg and 4 mg/kg PAR on days 8-10. Osteoclast-like cells on the bone surface of the radiocarpal joint and within the soft tissue of the hind paw were significantly lower following PAR treatment (p < 0.005). GFAP- and IBA1-positive cells in the PAG and RVM were significantly lower following treatment with 1 mg/kg (p < 0.0001 and p = 0.0004, respectively) and 4 mg/kg PAR (p < 0.0001 and p = 0.001, respectively). In the lumbar spinal cord, IBA1-positive cells were significantly lower in CAIA mice treated with 4 mg/kg PAR (p = 0.001). The findings indicate a suppressive effect of both low- and moderate-dose PAR on paw inflammation, osteoclast presence, and glial cell reactivity in a mild CAIA mouse model.


Assuntos
Artrite Experimental/tratamento farmacológico , Inflamação/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Animais , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/imunologia , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Microtomografia por Raio-X
2.
J Fish Dis ; 32(1): 15-25, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19245628

RESUMO

This study investigates the benefits of using prevalence as a summary measure of sea lice infestation on farmed Atlantic salmon, Salmo salar L. Aspects such as sampling effort, the relationship between abundance and prevalence arising from the negative binomial distribution, and how this relationship can be used to indicate the degree of aggregation of lice on a site at a given time point are discussed. As a case study, data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. Descriptive statistics and formal analysis using a linear modelling technique identified significant variations in sea lice prevalence across year class, region and season. Supporting evidence of a functional relationship between prevalence and abundance of sea lice is provided, which is explained through the negative binomial distribution.


Assuntos
Copépodes/fisiologia , Ectoparasitoses/veterinária , Doenças dos Peixes/epidemiologia , Salmo salar/parasitologia , Animais , Ectoparasitoses/epidemiologia , Modelos Lineares , Densidade Demográfica , Prevalência , Escócia/epidemiologia , Estações do Ano , Fatores de Tempo
3.
J Fish Dis ; 32(1): 89-100, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19245633

RESUMO

The long and narrow Hardanger fjord in western Norway has a high density of salmon farms and has had severe salmon lice, Lepeophtheirus salmonis, problems. In the years 2004-06, salmon lice numbers were recorded in selected salmon farms in the fjord as part of a larger research project. Most farm sites participated in a strategic control programme and were deloused between November and January in each year. The aim of the programme was to achieve a mean abundance of <0.3 adult female lice at this time and to minimize the infection pressure on wild smolts in the spring. Dedicated teams carried out detailed counting of lice on farmed fish in April-September each year. Temperature conditions were fairly similar throughout the fjord and amongst years, but wide variations in salinities were observed. The two innermost zones, B and C, had the lowest lice mean abundances, whereas the outermost zones, D and E, consistently had more lice. General linear model analyses showed that differences in adult female lice abundance between the zones were associated with differing levels of salinity and emamectin benzoate treatments strategically administered. Mean fish weight was significantly positively correlated with mean abundance of adult female lice.


Assuntos
Copépodes/fisiologia , Ectoparasitoses/veterinária , Doenças dos Peixes/parasitologia , Pesqueiros , Salmão , Animais , Feminino , Análise dos Mínimos Quadrados , Modelos Lineares , Oceanos e Mares , Densidade Demográfica , Dinâmica Populacional , Salinidade , Água do Mar/química , Temperatura , Fatores de Tempo
4.
Prev Vet Med ; 81(1-3): 135-47, 2007 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-17532070

RESUMO

Within the literature, most discussion of sampling protocols for monitoring aquatic parasites is based on the assumptions of simple random sampling. Recent research has shown that in monitoring parasite abundance on fish farms composed of discrete cages, care must be taken to properly account for the clustering which naturally occurs. This paper illustrates the effect of clustering in the context of monitoring ectoparasitic sea lice Lepeophtheirus salmonis and Caligus elongatus in salmon farms. The degree of clustering of sea lice infections in fish within cages is measured using the intraclass correlation coefficient (ICC). A wide range of ICC values from sites in Scotland and Norway were estimated for the chalimus and mobile stages of L. salmonis, and for C. elongatus mobiles. The analyses indicate that significant clustering of lice infections within cages occurs across lice species and stages on both Scottish and Norwegian farms. A Monte-Carlo simulation using two sets of data from Scottish farms with ICC values for adult L. salmonis of 0.35 [0.08-0.73, 95% CI] and for adult C. elongatus of 0.39 [0.16-0.69, 95% CI] were used to illustrate the implications of clustering. The protocols simulated reflect those typically used across a range of countries and production environments in which salmon are currently reared. The findings demonstrate that the "few fish from many cages" approach results in a marked improvement in precision when sampling aquatic one-host parasites in cage-based production systems.


Assuntos
Aquicultura , Copépodes/crescimento & desenvolvimento , Ectoparasitoses/veterinária , Doenças dos Peixes/diagnóstico , Salmo salar/parasitologia , Animais , Análise por Conglomerados , Ectoparasitoses/diagnóstico , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peixes , Método de Monte Carlo , Noruega , Doenças Parasitárias em Animais/diagnóstico , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Escócia
6.
Appl Ergon ; 5(1): 21-5, 1974 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15677140

RESUMO

Rational design of a process control system using an on-line computer requires a definition of the total control task and an allocation of function between the human operator and the machine. Both the nature of the total task and its subdivision depend very much on the process characteristics, which vary widely between different processes. The functions normally performed by a process control computer are described and those consequently left to the operator are defined. The wide variety of the operator's functions and the implications of this for studies of the operator's performance and for the design of the man-machine interface are emphasised. This article was originally presented as a paper at a symposium on Data Reduction, Communication and Presentation for Process Operation organised by the Institute of Measurement and Control at the University of Sussex, Brighton.

12.
J Fish Dis ; 31(4): 259-68, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18353017

RESUMO

Analyses of a unique database containing sea lice records over an 11 year period provide evidence of changing infestation patterns in Scotland. The data, collected from more than 50 commercial Atlantic salmon farms, indicate that both species of sea lice commonly found in Scotland, Lepeophtheirus salmonis and Caligus elongatus, have declined on farms over the past decade. Reductions for both species have been particularly marked since 2001 when more effective veterinary medicines became available. Treatment data were also available in the database and these show a growing trend towards the use of the in-feed medication emamectin benzoate (Slice), particularly in the first year of the salmon production cycle. However, this trend towards single product use has not been sustained in 2006, the latest year for which data are available. There is some evidence of region to region variation within Scotland with the Western Isles experiencing higher levels of infestation. However, compared to the levels observed between 1996 and 2000, all regions have benefited from reduced lice infestation, with the overall pattern showing a particular reduction in the second and third quarters of the second year of production.


Assuntos
Copépodes/fisiologia , Ectoparasitoses/veterinária , Doenças dos Peixes/epidemiologia , Salmo salar/parasitologia , Animais , Antiparasitários/uso terapêutico , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/epidemiologia , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/parasitologia , Pesqueiros , Geografia , Densidade Demográfica , Escócia/epidemiologia , Estações do Ano
13.
Ann Behav Med ; 29 Suppl: 35-45, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15921488

RESUMO

The purpose of this study was to identify the population prevalence across the stages of change (SoC) for regular physical activity and to establish the prevalence of people at risk. With support from the National Institutes of Health, the American Heart Association, and the Robert Wood Johnson Foundation, nine Behavior Change Consortium studies with a common physical activity SoC measure agreed to collaborate and share data. The distribution pattern identified in these predominantly reactively recruited studies was Precontemplation (PC) = 5% (+/- 10), Contemplation (C) = 10% (+/- 10), Preparation (P) = 40% (+/- 10), Action = 10% (+/- 10), and Maintenance = 35% (+/- 10). With reactively recruited studies, it can be anticipated that there will be a higher percentage of the sample that is ready to change and a greater percentage of currently active people compared to random representative samples. The at-risk stage distribution (i.e., those not at criteria or PC, C, and P) was approximately 10% PC, 20% C, and 70% P in specific samples and approximately 20% PC, 10% C, and 70% P in the clinical samples. Knowing SoC heuristics can inform public health practitioners and policymakers about the population's motivation for physical activity, help track changes over time, and assist in the allocation of resources.


Assuntos
Pesquisa Comportamental/métodos , Pesquisa Comportamental/normas , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Atividade Motora , Humanos
14.
Ann Hum Biol ; 8(1): 49-58, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6939407

RESUMO

A model developed by Stern to estimate the number of loci determining human skin colour in African-European hybrid populations is tested on recently collected reflectance data. Despite improved measurement scales and admixture estimates, and the use of statistical goodness-of-fit tests, contradictory results are obtained. It is shown that previous authors' use of visual inspection to compare expected and observed phenotype distributions introduced considerable bias into their results.


Assuntos
População Negra , Hibridização Genética , Modelos Genéticos , Pigmentação da Pele , África/etnologia , América Central , Europa (Continente)/etnologia , Feminino , Marcadores Genéticos , Humanos , Masculino , Fenótipo
15.
Am J Phys Anthropol ; 58(2): 215-9, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7114202

RESUMO

Skin colorimetry readings taken in Belize, Central America (formerly British Honduras) with the two most commonly used portable reflectometers reveal significant differences in mean reflectance between Garifuna (Black Caribs) and Creoles, and between Garifuna in two settlements. These differences are related to variation in African, Indian, and European admixture, as estimated from serological markers. Sex differences are not evident in univariate comparisons, but females are significantly lighter than males in multivariate analyses of variance. Polynomial age trends exist in some groups for certain variables, but account for a very small amount of the variation in skin color within these groups.


Assuntos
Fenômenos Fisiológicos da Pele , Adolescente , Adulto , África/etnologia , Fatores Etários , Belize , População Negra , Criança , Pré-Escolar , Cor , Colorimetria/métodos , Europa (Continente)/etnologia , Feminino , Humanos , Indígenas Centro-Americanos , Lactente , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , População Branca
16.
Am J Phys Anthropol ; 55(1): 81-8, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7258337

RESUMO

Cross-sectional data, consisting of anthropometric measurements for 347 adults males and 261 adult females in western Ireland measured during the 1930s, were used to determine the effects of aging and secular change upon stature. Estimates of statural loss due to aging were obtained using partial regression of stature on age while controlling for subischial length, and regression of the difference between observed stature and maximum predicted stature on age. Males show the effects of aging to a greater extent than do females. After correction for the effects of aging, the adjusted values of stature were progressed on age to estimate secular trend of stature. For males, there is a general increase of stature with time, excepting those born around 1878, while females generally show random variation with time. Both male and female adjusted stature decrease sharply around 1878, for which alternative historical explanations are proposed, relating to differential migration and survival.


Assuntos
Envelhecimento , Estatura , Adolescente , Adulto , Fatores Etários , Idoso , Antropometria , Feminino , História do Século XIX , História do Século XX , Humanos , Irlanda , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , População Rural , Fatores Sexuais
17.
Am J Phys Anthropol ; 48(4): 515-21, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-655272

RESUMO

Comparisons between skin colorimetry reports have been hampered by the common use of two different types of portable reflectometers, which sample reflectances at different wavelengths. In an attempt to provide direct comparability between the two machines, multiple linear regression equations were derived from reflectance spectrophotometry readings on 308 Black Caribs and 175 Creoles in Belize, Central America, using both machines. Cross validation tests show the coefficients presented are applicable to independent data sets and generally applicable to other heavily pigmented populations. Comparisons with previously published conversion formulae, which were from very small samples using simple linear regression, show a definite improvement in predictive accuracy when using multiple regression equations based on a large sample.


Assuntos
Colorimetria/instrumentação , Pigmentação da Pele , Belize , Colorimetria/normas , Humanos , Análise de Regressão
18.
Am J Phys Anthropol ; 49(4): 505-9, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-736107

RESUMO

Several different methods are suggested for the estimation of admixture proportions in hybrid populations based on skin reflectance data. These methods are applied to hybrid populations of known ancestry and yield results generally quite similar to those expected based on a simple genetic model. Results indicate the usefulness of these methods in hybridization studies and in the development and refinement of models of the genetics of skin color.


Assuntos
População Negra , Genética Populacional , Hibridização Genética , Pigmentação da Pele , População Branca , África , Colorimetria , Europa (Continente) , Humanos , Índia
19.
Ann Hum Biol ; 7(5): 411-28, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7235622

RESUMO

Models of population structure can be investigated using data on anthropometric variation among local populations. Anthropometric data collected by Dupertuis and Dawson during the 1930s were analysed from 347 males and 261 females in 12 towns in three counties of western Ireland. We hypothesized that recent migration would decrease the degree of among-group variation. To test this hypothesis, two additional samples were created by excluding known inter-county migrants from both male and female samples. Based on ethnographic data, a fifth sample was created using unmarried females only, in order to control partially for local migration upon marriage. Univariate and multivariate measures of relative differentiation were developed to compare different levels of migration and differences among the sexes. We found that the degree of among-group variation decreased as the amount of migration increased, in accordance with spatial models of population structure. Using non-parametric correlations of geographic and anthropometric distance, the observed patterns of differentiation were closely related to geography, suggesting a spatial model of gene flow to be appropriate in interpreting among-group variation. The female samples showed greater differentiation and higher correlations with geography than the males. It seems that this results from the sensitivity of males to developmental and local environmental influences, causing an increase in the relative amount of within-group variation.


PIP: The authors first introduce methods of applying the partitioned model of population structure developed by Wahlund to anthropometric data in order to assess the overall differentiation among subdivisions of a population. These methods are then applied to the analysis of data from rural western Ireland in an attempt to examine the effects of cultural variation in migration-related behavior on the degree of differentiation. The patterns of differentiation with reference to geographic distance are also briefly examined (SUMMARY IN FRE, GER)


Assuntos
Antropometria , População , Migrantes , Fatores Etários , Análise de Variância , Peso Corporal , Feminino , Humanos , Irlanda , Masculino , População Rural , Fatores Sexuais
20.
Am J Phys Anthropol ; 49(1): 35-8, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-677295

RESUMO

Twenty light-skinned adults were measured at the upper inner arm site using two commonly used reflectance spectrophotometers. Each subject was measured by each of three investigators to assess the influence of interobserver error on the reflectance readings. A repeated measures design analysis of variance showed no significant variance component due to observers.


Assuntos
Pigmentação da Pele , Humanos , Análise Espectral/métodos
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