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1.
N Z Vet J ; 69(2): 83-92, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33183158

RESUMO

AIMS: To estimate animal-level seroprevalence of Leptospira interrogans serovar Copenhageni and L. borgpetersenii serovars Ballum and Tarassovi, in beef cattle, sheep and deer on New Zealand farms, and herd/flock-level seroprevalence of any serovar when existing same-sera data for serovars Hardjobovis and Pomona were included, and to determine associations between risk factors and animal-level seroprevalence. METHODS: Banked sera from sheep (n = 82), beef (n = 54) and deer (n = 62) herds/flocks (n = 3,878 animals) from seven regions were analysed using the microscopic agglutination test. Titres of ≥48 were designated positive. Herds/flocks were considered positive if either ≥1, ≥2 or ≥3 animals were positive. Existing same-sera data for serovars Hardjobovis and Pomona were included to establish farm-level any-serovar seropositivity. Factors associated with serological status were analysed using generalised estimating equations. RESULTS: Animal-level seroprevalence for serovars Ballum, Copenhageni, and Tarassovi, respectively, was 13.7 (95% CI = 11.7-16.0)%, 12.6 (95% CI = 10.6-14.7)% and 18.0 (95% CI = 15.7-20.5)% for beef cattle, 10.5 (95% CI = 9.0-12.1)%, 16.7 (95% CI = 14.9-18.6)% and 14.0 (95% CI = 12.4-15.8)% for sheep and 6.6 (95% CI = 5.3-8.2)%, 15.5 (95% CI = 13.5-17.7)% and 3.6 (95% CI = 2.7-4.8)% for deer, respectively. Herd/flock-level seroprevalence for Ballum was 86.6, 52.4 and 39.0% for sheep, 85.2, 52.7 and 33.3% for beef cattle and 50.8, 27.9 and 21.3% for deer at definitions ≥1, ≥2 and ≥3 seropositive animals per species, respectively. For Copenhageni, corresponding data were 95.1, 73.2 and 56.1% for sheep, 68.5, 48.2 and 29.6% for beef cattle and 73.8, 57.4 and 41.0% for deer, and for Tarassovi, 80.5, 59.7 and 45.1% for sheep, 83.3, 68.5 and 61.1% for beef cattle, and 42.6, 16.4 and 4.9% for deer. Seropositivity to all serovars was observed from all regions, with some differences in seroprevalence observed between species and regions, but not between islands. Combining with Hardjobovis and Pomona data, herd/flock-level seropositivity for all animal species and all five Leptospira serovars was 100% at definition ≥1 animal positive, and 97.5 and 96.3% for sheep flocks, 87.8 and 97.8% for beef cattle herds, and 89.3 and 75% for deer herds at ≥2 and ≥3 animals positive, respectively. CONCLUSIONS: Seropositivity to serovars Ballum, Copenhageni and Tarassovi is common in sheep, beef cattle and deer New Zealand and most, or all farms have ≥1 livestock species seropositive to ≥1 serovar. CLINICAL RELEVANCE: Serovars Ballum, Tarassovi and Copenhageni should be considered when clinical or subclinical signs of leptospirosis are observed in sheep, beef cattle or deer. Livestock sector workers are potentially at risk of exposure.


Assuntos
Leptospira interrogans/isolamento & purificação , Leptospira/isolamento & purificação , Leptospirose/veterinária , Ruminantes/microbiologia , Animais , Bovinos , Cervos , Leptospira/classificação , Leptospira interrogans/classificação , Leptospirose/epidemiologia , Leptospirose/microbiologia , Nova Zelândia/epidemiologia , Estudos Soroepidemiológicos , Ovinos
2.
J Appl Microbiol ; 127(2): 370-378, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31009147

RESUMO

AIMS: A major drawback of using dairy slurry as fertilizer is that it may contains pathogens such as Mycobacterium avium subsp. paratuberculosis (MAP), and it could represent a risk to animal and public health. Thus, the aim of this study was to evaluate the fate of MAP and bacterial communities in dairy slurry after chemical treatments. METHODS AND RESULTS: Cattle slurry, naturally contaminated with MAP, was collected from a dairy herd and divided into 32 glass bottles which were assigned to eight different treatments (control, 3·0% CaO, 0·5% NaOH; 0·087%, 0·11% and 0·14% H2 SO4 ; and 1·0 and 2·5% KMnO4 ). Treated dairy slurry samples were evaluated at 0, 1, 3, 7, 15, 30 and 60-days following treatment application for viable MAP and dairy slurry pH, and in addition temperature in this material was monitored continuously. Bacterial counts were estimated at each sampling time. A Bayesian zero-inflated Poisson mixed model was fitted to assess the effect of each treatment on the count of MAP cells. Model results indicated that only the 3·0% CaO treatment had a statistically important negative effect on MAP counts during the study period. For most treatments, MAP was undetectable immediately after chemical treatment but re-appeared over time, in some replicates at low concentrations. However, in those cases MAP counts were not statistically different than the control treatment. Regarding the fate of the other bacterial populations, the Firmicutes phylum was the dominant population in the un-treated slurry while Clostridia class members were among the most prevalent bacteria after the application of most chemical treatments. CONCLUSION: Only 3% CaO treatment had a statistically important negative effect on MAP viability in cattle slurry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence of MAP partial control in dairy slurry. This information should be considered as a best management practice to reduce MAP and other pathogens for slurry management on dairy farms.


Assuntos
Antibacterianos/farmacologia , Indústria de Laticínios , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Animais , Teorema de Bayes , Compostos de Cálcio/farmacologia , Bovinos , Feminino , Fertilizantes , Esterco/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Óxidos/farmacologia
3.
Plant Biol (Stuttg) ; 21(1): 101-109, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30230155

RESUMO

Oceanic islands are dynamic settings that often promote within-island patterns of strong population differentiation. Species with high colonisation abilities, however, are less likely to be affected by genetic barriers, but island size may impact on species genetic structure regardless of dispersal ability. The aim of the present study was to identify the patterns and factors responsible for the structure of genetic diversity at the island scale in Phoenix canariensis, a palm species with high dispersal potential. To this end, we conducted extensive population sampling on the three Canary Islands where the species is more abundant and assessed patterns of genetic variation at eight microsatellite loci, considering different within-island scales. Our analyses revealed significant genetic structure on each of the three islands analysed, but the patterns and level of structure differed greatly among islands. Thus, genetic differentiation fitted an isolation-by-distance pattern on islands with high population densities (La Gomera and Gran Canaria), but such a pattern was not found on Tenerife due to strong isolation between colonised areas. In addition, we found a positive correlation between population geographic isolation and fine-scale genetic structure. This study highlights that island size is not necessarily a factor causing strong population differentiation on large islands, whereas high colonisation ability does not always promote genetic connectivity among neighbouring populations. The spatial distribution of populations (i.e. landscape occupancy) can thus be a more important driver of plant genetic structure than other island, or species' life-history attributes.


Assuntos
Phoeniceae/genética , Dispersão de Sementes/fisiologia , Árvores/genética , Variação Genética , Genética Populacional , Espanha , Especificidade da Espécie
4.
Acta Ortop Mex ; 33(3): 173-181, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32246610

RESUMO

INTRODUCTION: It is essential that orthopaedic resident physicians be highly proficient in all aspects, considering the balance between supply, demand, need and context. Fundamental to identify the capacity and quality installed for their training in Mexico. MATERIAL AND METHODS: Observational Study, transverse, non-probabilistic sampling-conglomerates, in two phases. The instrument has 8 domains, 57 variables and 4,867 items. 60 graduate professors of 20 states, 50 hospital sites, 22 university programs. RESULTS: 1,038 years of experience (collective intelligence), 17 years of experience/teacher (01 to 50 years). Identified: acute pathology 30 (2 to 90%), chronic pathology 30 (5 to 96%), patients 15 years, 10 (3 to 30%), patients between 15 and 65 years, 47 (2 to 78%), patients 65 years, 20 (2 to 60%), number of beds/seat 20 (2 to 510), number of clinics 3 (1 to 48), number of surgical procedures/headquarters per year at the national level, was 960 (50 to 24,650). The national average per resident doctor is 362 surgeries/year with 1,450 surgical times/year. CONCLUSIONS: The needs and resources for the training of physicians specializing in orthopedics/traumatology are highly heterogeneous, so it should be adapted to the epidemiological needs of the region of influence, in an area of epidemiological transition. 62.2% expressed not having or have bad academic and scientific infrastructure at its headquarters, more than 50% without rotation overseas and 90% without regular scientific production.


INTRODUCCIÓN: Es fundamental que los médicos residentes de ortopedia (traumatología) sean altamente competentes en todos los aspectos, considerando el equilibrio entre la oferta, demanda, necesidad y contexto. Es primordial identificar la capacidad y calidad instalada para su formación en México. MATERIAL Y MÉTODOS: Estudio observacional, transversal, muestreo no probabilístico-conglomerados, en dos fases. El instrumento tiene ocho dominios, 57 variables y 4,867 ítems. Sesenta profesores de postgrado de 20 estados, 50 sedes hospitalarias, 22 programas universitarios. RESULTADOS: 1,038 años de experiencia (inteligencia colectiva), 17 años de experiencia/profesor (01 a 50 años). Se identificó: patología aguda 30 (2 a 90%), patología crónica 30 (5 a 96%), pacientes 15 años, 10 (3 a 30%), pacientes entre 15 y 65 años, 47 (2 a 78%), pacientes 65 años, 20 (2 a 60%), número de camas/sede 20 (2 a 510), número de consultorios 3 (1 a 48), el número de procedimientos quirúrgicos/sede al año a nivel nacional fue de 960 (50 a 24,650). La media nacional por médico residente es de 362 cirugías/año con 1,450 momentos quirúrgicos/año. CONCLUSIONES: Las necesidades y recursos para la formación de médicos especialistas en ortopedia/traumatología son en alto grado heterogéneos, por lo cual se debería adaptar a las necesidades epidemiológicas de la región de influencia, en un ámbito de transición epidemiológica. Sesenta y dos punto dos por ciento expresó no tener o tener deficiente infraestructura académica y científica en su sede, más de 50% sin rotación al extranjero y 90% sin producción científica regular.


Assuntos
Internato e Residência , Procedimentos Ortopédicos , Ortopedia , Humanos , México , Inquéritos e Questionários
5.
N Z Vet J ; 66(6): 302-311, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30122123

RESUMO

AIMS To determine seroprevalence of Leptospira borgpetersenii serovar Hardjo and L. interrogans serovar Pomona in beef cattle, sheep and deer in New Zealand and the association between farm-level risk factors and seroprevalence. METHODS Between June 2009 and July 2010, 20 serum samples per flock or herd were collected from 162 sheep flocks, and 116 beef cattle and 99 deer herds from 238 farms, along with farm data by interview. Samples were tested for antibodies to serovars Hardjo and Pomona by microscopic agglutination testing, with a titre ≥48 being positive. Species-specific associations between herd-level seroprevalence (number of seropositive animals, for each serovar, divided by the number of animals tested) and herd-level risk factors were determined by multivariable logistic regression analysis. Vaccinated animals were excluded from seroprevalence estimates but included in multivariable analyses. RESULTS For sheep (n=3,339), animal-level seroprevalence was 43.6 (95% CI=41.9-45.3)% for serovar Hardjo and 14.1 (95% CI=12.9-15.3)% for serovar Pomona; for beef cattle(n=1,886), it was 45.6 (95% CI=43.3-47.9)% for Hardjo and 19.6 (95% CI=17.9-21.5)% for Pomona; and for deer (n=1,870), it was 26.3 (95% CI=24.3-28.4)% for Hardjo, 8.8 (95% CI=7.6-10.2)% for Pomona. In sheep flocks (n=161), flock-level prevalence for Hardjo varied from 77.9-91.3%, and for Pomona from 40.4-73.9%, when ≥1, ≥2 or ≥3 animals were seropositive. In beef herds (n=95), herd-level prevalence for Hardjo varied from 79.0-90.5%, and for Pomona from 42.1-68.4%. In deer herds (n=93), herd-level prevalence for Hardjo varied from 45.2-59.1%, and for Pomona from 22.6-48.4%. For sheep flocks, herd-level seroprevalence for Hardjo was associated with flock size (OR=1.56) and number of dogs (OR=0.75), and for Pomona, seroprevalence varied with region. For beef cattle, herd-level seroprevalence for Hardjo was associated with herd size (OR=1.4), presence of dams (OR=0.6) and vaccination (OR=2.9), and for Pomona, co-grazing with deer (OR=0.4), vaccination (OR=3.22), presence of dams (OR=0.2) and streams (OR=2.7). For deer herds, seroprevalence for Hardjo or Pomona was associated with herd size (OR=1.6 and 1.8) and varied with region, and for Pomona seroprevalence varied with season (summer vs. winter: OR=4.8). CONCLUSIONS Serovars Hardjo and Pomona were highly prevalent at herd and animal levels, with serovar Hardjo highest in all species. Larger herd size was the common risk factor for seroprevalence in all livestock species.


Assuntos
Doenças dos Bovinos/epidemiologia , Cervos/microbiologia , Leptospirose/veterinária , Doenças dos Ovinos/epidemiologia , Criação de Animais Domésticos , Animais , Anticorpos Antibacterianos , Vacinas Bacterianas/uso terapêutico , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/prevenção & controle , Cervos/sangue , Entrevistas como Assunto , Leptospira , Leptospirose/sangue , Leptospirose/epidemiologia , Leptospirose/prevenção & controle , Modelos Logísticos , Nova Zelândia/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Sorogrupo , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/prevenção & controle
6.
Avian Dis ; 60(4): 805-809, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27902900

RESUMO

Many developing countries lack sufficient resources to conduct animal disease surveillance. In recent years, participatory epidemiology has been used to increase the cover and decrease the costs of surveillance. However, few diagnostic performance assessments have been carried out on participatory methods. The objective of the present study was to estimate the diagnostic performance of practitioners working for the Community-Based Animal Health and Outreach (CAHO) program, which is a participatory disease surveillance system for the detection of highly pathogenic avian influenza outbreaks in Egypt. CAHO practitioners' diagnostic assessment of inspected birds was compared with real-time reverse-transcriptase polymerase chain reaction (RRT-PCR) test results at the household level. Diagnostic performance was estimated directly from two-by-two tables using RRT-PCR as a reference test in two different scenarios. In the first scenario, only results from chickens were considered. In the second scenario, results for all poultry species were analyzed. Poultry flocks in 916 households located in 717 villages were inspected by CAHO practitioners, who collected 3458 bird samples. In the first scenario, CAHO practitioners presented sensitivity (Se) and specificity (Sp) estimates of 40% (95% confidence interval [CI]: 21%-59%) and 92% (95% CI: 91%-94%), respectively. In the second scenario, diagnostic performance estimates were Se = 47% (95% CI: 29%-65%) and Sp = 88% (95% CI: 86%-90%). A significant difference was observed only between Sp estimates (P < 0.01). Practitioners' diagnostics and RRT-PCR results were in very poor agreement with kappa values of 0.16 and 0.14 for scenarios 1 and 2, respectively. However, the use of a broad case definition, the possible presence of immunity against the virus in replacement birds, and the low prevalence observed during the survey would negatively affect the practitioners' performance.


Assuntos
Técnicas e Procedimentos Diagnósticos/veterinária , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/diagnóstico , Doenças das Aves Domésticas/diagnóstico , Vigilância de Evento Sentinela/veterinária , Animais , Aves/virologia , Galinhas , Egito/epidemiologia , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Sensibilidade e Especificidade
7.
Mol Ecol ; 24(4): 726-41, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25580539

RESUMO

Ecological and evolutionary studies largely assume that island populations display low levels of neutral genetic variation. However, this notion has only been formally tested in a few cases involving plant taxa, and the confounding effect of selection on genetic diversity (GD) estimates based on putatively neutral markers has typically been overlooked. Here, we generated nuclear microsatellite and plastid DNA sequence data in Periploca laevigata, a plant taxon with an island-mainland distribution area, to (i) investigate whether selection affects GD estimates of populations across contrasting habitats; and (ii) test the long-standing idea that island populations have lower GD than their mainland counterparts. Plastid data showed that colonization of the Canary Islands promoted strong lineage divergence within P. laevigata, which was accompanied by selective sweeps at several nuclear microsatellite loci. Inclusion of loci affected by strong divergent selection produced a significant downward bias in the GD estimates of the mainland lineage, but such underestimates were substantial (>14%) only when more than one loci under selection were included in the computations. When loci affected by selection were removed, we did not find evidence that insular Periploca populations have less GD than their mainland counterparts. The analysis of data obtained from a comprehensive literature survey reinforced this result, as overall comparisons of GD estimates between island and mainland populations were not significant across plant taxa (N = 66), with the only exception of island endemics with narrow distributions. This study suggests that identification and removal of markers potentially affected by selection should be routinely implemented in estimates of GD, particularly if different lineages are compared. Furthermore, it provides compelling evidence that the expectation of low GD cannot be generalized to island plant populations.


Assuntos
Variação Genética , Genética Populacional , Ilhas , Periploca/genética , Seleção Genética , Evolução Biológica , DNA de Cloroplastos/genética , DNA de Plantas/genética , Ecossistema , Deriva Genética , Loci Gênicos , Repetições de Microssatélites , Dados de Sequência Molecular , Espanha
8.
Mol Ecol ; 22(6): 1546-57, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23379976

RESUMO

Refugia are expected to preserve genetic variation of relict taxa, especially in polyploids, because high gene dosages could prevent genetic erosion in small isolated populations. However, other attributes linked to polyploidy, such as asexual reproduction, may strongly limit the levels of genetic variability in relict populations. Here, ploidy levels and patterns of genetic variation at nuclear microsatellite loci were analysed in Prunus lusitanica, a polyploid species with clonal reproduction that is considered a paradigmatic example of a Tertiary relict. Sampling in this study considered a total of 20 populations of three subspecies: mainland lusitanica (Iberian Peninsula and Morocco), and island azorica (Azores) and hixa (Canary Islands and Madeira). Flow cytometry results supported an octoploid genome for lusitanica and hixa, whereas a 16-ploid level was inferred for azorica. Fixed heterozygosity of a few allele variants at most microsatellite loci resulted in levels of allelic diversity much lower than those expected for a high-order polyploid. Islands as a whole did not contain higher levels of genetic variation (allelic or genotypic) than mainland refuges, but island populations displayed more private alleles and higher genotypic diversity in old volcanic areas. Patterns of microsatellite variation were compatible with the occurrence of clonal individuals in all but two island populations, and the incidence of clonality within populations negatively correlated with the estimated timing of colonization. Our results also suggest that gene flow has been very rare among populations, and thus population growth following founder events was apparently mediated by clonality rather than seed recruitment, especially in mainland areas. This study extends to clonal taxa the idea of oceanic islands as important refugia for biodiversity, since the conditions for generation and maintenance of clonal diversity (i.e. occasional events of sexual reproduction, mutation and/or seed immigration) appear to have been more frequent in these enclaves than in mainland areas.


Assuntos
Biodiversidade , Variação Genética , Genética Populacional , Poliploidia , Prunus/genética , DNA de Plantas/genética , Evolução Molecular , Fluxo Gênico , Genoma de Planta , Genótipo , Geografia , Ilhas , Região do Mediterrâneo , Repetições de Microssatélites , Análise de Sequência de DNA
9.
N Z Vet J ; 61(3): 147-52, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23441922

RESUMO

AIM: To estimate the prevalence of Mycobacterium avium subsp. paratuberculosis (Map) in farmed deer with no gross post-mortem evidence of Map infection slaughtered in New Zealand, and to assess predictors of infection. METHODS: Mesenteric lymph node (MLN) samples (n = 251) were collected from 60 lines of deer presented at two slaughterhouses in the North and two in the South Island of New Zealand between October 2008 and January 2009 and cultured for Map. Estimates of individual animal prevalence for each island were adjusted to account for the clustering of individual observations within herds. The national herd prevalence estimate was calculated as a weighted mean, with weights being the proportion of herds from which deer were slaughtered at North and South Island slaughterhouses among all herds slaughtering deer throughout New Zealand. Age, gender, and the presence of other carcasses with enlarged and/or granulomatous MLN in the same line (line status) were assessed as predictors of infection using multivariable logistic regression. RESULTS: A national cluster-adjusted individual animal prevalence of 45 (95% CI = 30-60)% was estimated, with North and South Island prevalences of 29 (95% CI = 16-45)% and 51 (95% CI = 36-66)%, respectively. Line status was a strong predictor of infection in young deer (OR 7.1, 95% CI = 2.4-21.5), but not in older deer. Herd-level prevalence was 44 (95% CI = 24-64)% in the North Island and 67 (95% CI = 49-85)% in the South Island. Weighted adjustment resulted in a national herd-level prevalence estimate of 59 (95% CI = 41-78)%. CONCLUSIONS: This study has provided a national baseline prevalence estimate for Map infection at the individual and herd-level, showing a contrast between the North and South Islands. More research to investigate the factors contributing to the difference in infection prevalence seen between the islands may help to identify suitable control measures for Map in deer herds.


Assuntos
Cervos , Linfadenite Mesentérica/veterinária , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/patologia , Animais , Estudos Transversais , Linfadenite Mesentérica/patologia , Nova Zelândia/epidemiologia , Paratuberculose/epidemiologia , Prevalência
10.
Artigo em Espanhol | LILACS | ID: lil-651882

RESUMO

Este estudio, in vitro, determinó si los dientes con clareamiento presentan mayor cambio de color en el tiempo que los no tratados, al someterse a tinción con bebidas cromógenas, café, té y vino. Se utilizaron 45 incisivos sanos de bovino conservados en suero a 37ºC. Cada espécimen se dividió en dos mitades, una sometida a clareamiento con peróxido de hidrógeno al 35 por ciento y otra control. Se midió color con Espectrofotómetro Vita EasyShade. Se dividieron los especímenes al azar en grupos de 15 y fueron sumergidos en café, té y vino, durante 10 minutos, 20 veces, registrando color después de cada inmersión. Los datos fueron analizados con ANOVA y Test de Tukey, con 95 por ciento de intervalo de confianza. Los resultados mostraron que, el clareamiento modifica significativamente (p=0.05) el color en los tres grupos (GC=85.8 a 95.1; GT=87.4 a 97.3 y GV=90.8 a 99.3), la recidiva de color se observa a lo largo de las 20 inmersiones, siendo significativa la diferencia de valores ΔE iniciales (GC=18.89; GT=22.97; GV=56.46) y finales (GC=5.56; GT=5.38; GV=12.49). El grupo tratado presenta mayor descenso de unidades ΔE a lo largo de las inmersiones, por lo que es el más teñido (GCcontrol=20.98-5.01; GTcontrol=17.11-3.66; GVcontrol=54.62-11.49). Las tres bebidas cromógenas causan recidiva de color en los dientes clareados, siendo el vino el que causa mayor tinción. Se concluyó que las piezas tratadas, sometidas a los tres tipos de cromógenos, tienen mayor cambio de color que las que no lo son, pero finalmente no se oscurecen más que las no tratadas.


This in vitro study established if teeth treated with dental bleaching have a higher change of color over time than those that aren’t treated, when subjected to three chromogenic beverages (coffee, tea and red wine). 45 healthy bovine incisors were used, maintained in 0.9 percent sodium chloride, at 37ºC. Every specimen was divided into 2 half; one half was subjected to dental bleaching with 35 percent hydrogen peroxide and the other was taken as control. The color was measured with the Vita EasyShade Spectrophotometer. The specimens were randomly divided in groups of 15, and were immersed in coffee, tea and red wine for 10 minutes, 20 times, the value being recorded after each immersion. The data was analyzed with ANOVA and Tukey test, using 95 percent of confidence interval. Results show that bleaching significantly modifies (p=0.05) the color in the three groups (GC=85.8 to 95.1; GT=87.4 to 97.3 y GV=90.8 to 99.3). Color relapse in the three groups was observed along the 20 immersions. Initial ΔE values (GC=18.89; GT=22.97; GV=56.46) were significantly different than final ΔE values (GC=5.56; GT=5.38; GV=12.49). The chromogenic beverages stained more the treated group because a higher ΔE units decrease was observed in this group (GCcontrol=20.98-5.01; GTcontrol=17.11-3.66; GV control=54.62-11.49). The three chromogenic beverages produced color relapse in the bleaching teeth, being red wine the one causing more staining. It was concluded that the specimens treated subjected to three kinds of chromogenic, had higher change of color than control group, but at the end the treated group doesn’t get more stained than the control group.


Assuntos
Animais , Café/efeitos adversos , Descoloração de Dente/etiologia , Chá , Clareamento Dental , Vinho/efeitos adversos , Análise de Variância , Espectrofotometria
11.
Prev Vet Med ; 106(1): 63-74, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22480407

RESUMO

This study aimed to develop a mathematical model describing the dynamics of paratuberculosis (PTB) in red deer (Cervus elaphus) under pastoral farming conditions in New Zealand. The model examined infectivity differences between ovine and bovine strains of Mycobacterium avium subspecies paratuberculosis (MAP) and seasonality of MAP survival. We also evaluate variable use of pasture and the effect of management interventions on the infection prevalence and annual clinical incidence of PTB. A state-transition model was developed and calibrated to observed data on both prevalence of infection and incidence of clinical PTB. To accommodate specific PTB features for deer, the model included a fast and a slow track for progression of infection to disease. MAP on pasture was the source for horizontal transmission and infected dams for vertical transmission. In the presence of a single strain, an infectivity reduction of up to 80% allowed MAP to persist in the herd (R(0)>1). For mixed infection by two strains however, a 30% reduction in infectivity of one strain was sufficient to outcompete a strain with lower infectivity, suggesting that mixed infection of MAP strains with different infectivity may not be common in deer. The model showed that seasonal variation of MAP survival on pasture had little impact on transmission dynamics, and that rotational grazing with pasture spelling vs. permanent grazing of the same paddock reduced both infection prevalence and clinical PTB by about 50%. Based on model outputs, early detection of young deer in a high-shedding state was the most effective means of controlling PTB among the tested scenarios.


Assuntos
Criação de Animais Domésticos/métodos , Cervos/microbiologia , Modelos Biológicos , Modelos Teóricos , Paratuberculose/transmissão , Animais , Progressão da Doença , Suscetibilidade a Doenças/veterinária , Feminino , Masculino , Matemática , Mycobacterium avium subsp. paratuberculosis/classificação , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Nova Zelândia , Paratuberculose/microbiologia , Estações do Ano , Fatores de Tempo
12.
Plant Cell Environ ; 34(5): 800-10, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21276011

RESUMO

Trees are modular organisms that adjust their within-crown morphology and physiology in response to within-crown light gradients. However, whether within-plant variation represents a strategy for optimizing light absorption has not been formally tested. We investigated the arrangement of the photosynthetic surface throughout one day and its effects on the photosynthetic process, at the most exposed and most sheltered crown layers of a wild olive tree (Olea europaea L.). Similar measurements were made for cuttings taken from this individual and grown in a greenhouse at contrasted irradiance-levels (100 and 20% full sunlight). Diurnal variations in light interception, carbon fixation and carbohydrate accumulation in sun leaves were negatively correlated with those in shade leaves under field conditions when light intensity was not limiting. Despite genetic identity, these complementary patterns were not found in plants grown in the greenhouse. The temporal disparity among crown positions derived from specialization of the photosynthetic behaviour at different functional and spatial scales: architectural structure (crown level) and carbon budget (leaf level). Our results suggest that the profitability of producing a new module may not only respond to construction costs or light availability, but also rely on its spatio-temporal integration within the productive processes at the whole-crown level.


Assuntos
Olea/fisiologia , Fotossíntese , Árvores/fisiologia , Metabolismo dos Carboidratos , Dióxido de Carbono/metabolismo , Olea/anatomia & histologia , Olea/efeitos da radiação , Fotoperíodo , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Luz Solar , Árvores/anatomia & histologia , Árvores/efeitos da radiação
13.
Artigo em Espanhol | LILACS | ID: lil-627538

RESUMO

Introducción: La rehabilitación de pacientes con desgastes severos es compleja cuando se determina un aumento de Dimensión Vertical. Los métodos de evaluación de Dimensión Vertical no entregan una información precisa para definir cuánto incremento es necesario. El análisis cefalométrico aparece como una opción adicional a las herramientas clínicas, específicamente el análisis de Ricketts contiene mediciones verticales del tercio inferior, a través del ángulo Altura Facial Inferior, cuyo valor normal es de 47o, pero con una desviación estándar alta. Objetivo: Determinar si el ángulo Altura Inferior de Ricketts es sensible a incrementos de Dimensión Vertical Oclusal (DVO). Método: A nueve sujetos entre 20 y 30 años se les realizó un análisis cefalométrico con el fin de medir el ángulo Altura Inferior de Ricketts, en posición MIC, y luego con incrementos de la Dimensión Vertical de 1, 3 y 5 mm. Resultados: Los resultados mostraron que el valor del ángulo Altura Inferior de Ricketts (AFI) aumentó con los incrementos de la Dimensión Vertical Oclusal de 1, 3 y 5 mm en todos los sujetos. Al análisis estadístico no paramétrico de Friedman, estos resultados son significativos (p=0.000). A la prueba Post Hoc de Siegel y Castellon la variación del ángulo Altura Inferior de Ricketts con el incremento de 1 mm de DVO no es significativa. Conclusiones: Se puede sugerir que el análisis cefalométrico de Ricketts, a través de la medición del ángulo AFI, es capaz de detectar incrementos en la DVO, pero la variación que se produce con 1 mm de incremento no es estadísticamente significativa.


Introduction: Oral rehabilitation of patients with severe wear, becomes complex when there is a need to increase Vertical Dimension. Evaluation methods of Vertical Dimension do not deliver accurate information to define as increase is necessary. The cephalometric analysis appears as an additional option to the clinical tools, specific Ricketts analysis containing vertical measurements of the lower third, through the Lower Facial Height angle, whose normal value is 47o, but with a high-standard deviation. Objective: To determine whether the Lower Height Ricketts angle is sensitive to increases in Oclusal Vertical Dimension (OVD). Method: Nine subjects aged 20 to 30 years-old underwent cephalometric analysis in order to measure the Lower Height Ricketts angle in centric occlusion position, then increasing OVD in 1, 3 and 5 mm. Results: Lower Height Ricketts angle showed an increase as OVD of 1, 3 and 5 mm augmented in all subjects. Nonparametric Friedman´s statistical analysis was applied, being the results statistically significant (p=0.000). According to Post Hoc test of Siegel and Castellon, Lower Height Ricketts angle variation of 1 mm is not statistically significant. Conclusions: It may be suggested that the Ricketts cephalometric analysis by measuring the Lower Height angle is able to detect increases in the OVD, but the change that occurs within 1 mm increase is not statistically significant.


Assuntos
Humanos , Adulto , Cefalometria/métodos , Dimensão Vertical
14.
Oecologia ; 164(3): 647-55, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20532918

RESUMO

Phenotypic variation of traits can reflect the ability of plants to adjust to particular environments, but how much of this variation is heritable is not frequently analyzed in natural populations. In the present paper, we investigated the patterns of phenotypic expression in light-related leaf traits of Olea europaea subsp. guanchica, a woody sclerophyllous species endemic to the Canary Islands. We explored phenotypic differentiation and heritable variation across several island populations differing in light environment. A suite of morpho-functional (leaf size, SLA and leaf angle) and physiological (pigment pools: Chl a/b ratio, xantophyll cycle and ß-carotene) traits was measured in six populations on three islands. In addition, we estimated heritabilities for these traits following Ritland's method. Variation in morpho-functional, but not in physiological, traits was observed across the islands and was significantly related to the amount of diffuse light experienced by each population. In addition, significant heritabilities were found for morpho-functional traits, whereas expression of similar phenotypes among populations was accompanied by a lack of heritable variation in physiological traits. Most recently established populations did not exhibit lower heritabilities in quantitative traits than older populations, and apparently displayed congruent phenotypes under the local conditions. Our results strongly support the idea that different types of traits show contrasted levels of genetic and phenotypic variation in populations experiencing marked environmental differences.


Assuntos
Luz , Olea/anatomia & histologia , Fenótipo , Variação Genética , Olea/genética , Fotossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Temperatura
15.
Plant Biol (Stuttg) ; 11(3): 464-72, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19470117

RESUMO

Evergreen oaks are an emblematic element of the Mediterranean vegetation and have a leaf phenotype that seems to have remained unchanged since the Miocene. We hypothesise that variation of the sclerophyll phenotype among Iberian populations of Quercus coccifera is partly due to an ulterior process of ecotypic differentiation. We analysed the genetic structure of nine Iberian populations using ISSR fingerprints, and their leaf phenotypes using mean and intracanopy plasticity values of eight morphological (leaf angle, area, spinescence, lobation and specific area) and biochemical traits (VAZ pool, chlorophyll and beta-carotene content). Climate and soil were also characterised at the population sites. Significant genetic and phenotypic differences were found among populations and between NE Iberia and the rest of the populations of the peninsula. Mean phenotypes showed a strong and independent correlation with both genetic and geographic distances. Northeastern plants were smaller, less plastic, with smaller, spinier and thicker leaves, a phenotype consistent with the stressful conditions that prevailed in the steppe environments of the refugia within this geographic area during glaciations. These genetic, phenotypic, geographic and environmental patterns are consistent with previously reported palaeoecological and common evidence. Such consistency leads us to conclude that there has been a Quaternary divergence within the sclerophyllous syndrome that was at least partially driven by ecological factors.


Assuntos
Ecossistema , Variação Genética , Genética Populacional , Genótipo , Fenótipo , Folhas de Planta/genética , Quercus/genética , Geografia , Folhas de Planta/anatomia & histologia , Quercus/anatomia & histologia , Espanha , Estresse Fisiológico
16.
Mol Ecol ; 18(3): 454-67, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19143937

RESUMO

Geographical isolation and polyploidization are central concepts in plant evolution. The hierarchical organization of archipelagos in this study provides a framework for testing the evolutionary consequences for polyploid taxa and populations occurring in isolation. Using amplified fragment length polymorphism and simple sequence repeat markers, we determined the genetic diversity and differentiation patterns at three levels of geographical isolation in Olea europaea: mainland-archipelagos, islands within an archipelago, and populations within an island. At the subspecies scale, the hexaploid ssp. maroccana (southwest Morocco) exhibited higher genetic diversity than the insular counterparts. In contrast, the tetraploid ssp. cerasiformis (Madeira) displayed values similar to those obtained for the diploid ssp. guanchica (Canary Islands). Geographical isolation was associated with a high genetic differentiation at this scale. In the Canarian archipelago, the stepping-stone model of differentiation suggested in a previous study was partially supported. Within the western lineage, an east-to-west differentiation pattern was confirmed. Conversely, the easternmost populations were more related to the mainland ssp. europaea than to the western guanchica lineage. Genetic diversity across the Canarian archipelago was significantly correlated with the date of the last volcanic activity in the area/island where each population occurs. At the island scale, this pattern was not confirmed in older islands (Tenerife and Madeira), where populations were genetically homogeneous. In contrast, founder effects resulted in low genetic diversity and marked genetic differentiation among populations of the youngest island, La Palma.


Assuntos
Efeito Fundador , Variação Genética , Genética Populacional , Olea/classificação , Olea/genética , Poliploidia , Genoma de Planta , Marrocos , Olea/crescimento & desenvolvimento , Polimorfismo de Fragmento de Restrição , Sequências Repetitivas de Ácido Nucleico , Espanha , Especificidade da Espécie
17.
Ann Bot ; 101(1): 25-30, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18024415

RESUMO

BACKGROUND: Phylogenetic and phylogeographic investigations have been previously performed to study the evolution of the olive tree complex (Olea europaea). A particularly high genomic diversity has been found in north-west Africa. However, to date no exhaustive study has been addressed to infer putative polyploidization events and their evolutionary significance in the diversification of the olive tree and its relatives. METHODS: Representatives of the six olive subspecies were investigated using (a) flow cytometry to estimate genome content, and (b) six highly variable nuclear microsatellites to assess the presence of multiple alleles at co-dominant loci. In addition, nine individuals from a controlled cross between two individuals of O. europaea subsp. maroccana were characterized with microsatellites to check for chromosome inheritance. KEY RESULTS: Based on flow cytometry and genetic analyses, strong evidence for polyploidy was obtained in subspp. cerasiformis (tetraploid) and maroccana (hexaploid), whereas the other subspecies appeared to be diploids. Agreement between flow cytometry and genetic analyses gives an alternative approach to chromosome counting to determine ploidy level of trees. Lastly, abnormalities in chromosomes inheritance leading to aneuploid formation were revealed using microsatellite analyses in the offspring from the controlled cross in subsp. maroccana. CONCLUSIONS: This study constitutes the first report for multiple polyploidy in olive tree relatives. Formation of tetraploids and hexaploids may have played a major role in the diversification of the olive complex in north-west Africa. The fact that polyploidy is found in narrow endemic subspecies from Madeira (subsp. cerasiformis) and the Agadir Mountains (subsp. maroccana) suggests that polyploidization has been favoured to overcome inbreeding depression. Lastly, based on previous phylogenetic analyses, we hypothesize that subsp. cerasiformis resulted from hybridization between ancestors of subspp. guanchica and europaea.


Assuntos
Repetições de Microssatélites , Olea/genética , Poliploidia , Alelos , Cruzamentos Genéticos , Citometria de Fluxo , Marcadores Genéticos , Genoma de Planta , Padrões de Herança , Polimorfismo Genético
18.
Rev. chil. pediatr ; 76(6): 580-588, nov.-dic. 2005. tab, graf
Artigo em Espanhol | LILACS | ID: lil-432993

RESUMO

La respuesta de fase aguda es inespecífica y su comportamiento está poco caracterizado en niños sometidos a cirugía programada no complicada. Objetivos: Caracterizar el comportamiento de reactantes de fase aguda en niños enfrentados a una intervención quirúrgica programada y compararla según grado de estrés quirúrgico y edad. Pacientes y Métodos: Se estudiaron prospectivamente lactantes, preescolares y escolares ingresados para cirugía programada. Se evaluó proteína C-reactiva (PCR), albúmina, prealbúmina y glicemia en preoperatorio y en el período postoperatorio entre las 6 a 12 horas, 48 horas y cuarto día. Se agruparon los niños según grado de estrés quirúrgico mediante un score validado. Resultados: Ingresaron 40 pacientes, 20 varones, edad 4,4 años (rango 3 meses a 16 años). Según grado de estrés quirúrgico, 25 pertenecían al grupo leve y 15 al grupo moderado. La cinética de los parámetros metabólicos según grupo de estrés, evaluado mediante ANOVA de medidas repetidas, no mostró diferencias significativas. Al analizar los parámetros en los distintos momentos estudiados (t de student), la PCR fue significativamente mayor y la prealbúmina y albúmina significativamente menor en el grupo de mayor estrés. Las variaciones de glicemia, no mostraron diferencias significativas en el grupo total, en ninguno de los tiempos analizados. No hubo diferencias en el comportamiento en el tiempo de los parámetros evaluados según edad. Conclusiones: La respuesta inflamatoria en niños sometidos a cirugía programada no complicada, no difiere significativamente según edad ni grado de estrés quirúrgico leve o moderado. Puede objetivarse clínicamente a través de la medición seriada de parámetros como PCR, albúmina y prealbúmina. La cinética de la glicemia es de menor utilidad en este tipo de pacientes.


Assuntos
Masculino , Adolescente , Humanos , Feminino , Lactente , Pré-Escolar , Criança , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Proteínas de Fase Aguda/análise , Proteínas de Fase Aguda/metabolismo , Estresse Fisiológico , Análise de Variância , Albumina Sérica/análise , Evolução Clínica , Estudos de Coortes , Glicemia/análise , Inflamação , Cinética , Estudos Prospectivos , Proteína C-Reativa/análise , Índice de Gravidade de Doença
19.
J Exp Mar Biol Ecol ; 259(2): 155-170, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11343710

RESUMO

Biochemical components of gonad and adductor muscle for diploid and triploid catarina scallop, Argopecten ventricosus, were evaluated and compared at four periods in 1 year (January, April, June, and October). Two comparisons were done. The first one compared an untreated control (diploid) vs. a triploidy-treated group for which the percentage of triploids was 57%. The second comparison was done on a group derived from within the triploidy-treated group, separating diploids (internal control) from triploids ('putative triploids'). Regardless of which comparison, in the gonad diploid scallops had larger concentrations of proteins, carbohydrates, lipids, and acylglycerols than triploid scallops. This reflects the maturation processes in diploid scallops vs. the sterility seen in most triploid scallops, and it is particularly supported by the consistently larger concentration of acylglycerols in gonads of diploids than in triploids. The gonad index of the internal control (diploid) group was significantly larger than that seen in the putative triploid group at all sampling periods but October, when none of the gonad biochemical components were different between ploidy groups.Triploid scallops had a significantly larger muscle index than diploids from April to October. This can be caused by a larger gain in muscle tissue in triploids than diploids from January to June. However, there were no consistent differences in any of the biochemical components evaluated in adductor muscle of diploids and triploids. The use of freshly ingested food rather than reserve mobilization from muscle in diploids is suggested by these results. Nutrients derived from ingested food are apparently used for muscle growth in triploids, whereas in diploids those nutrients serve primarily for gonad development. The importance of freshly ingested food for maintenance and growth is suggested because the decline in biochemical components seen in October in both muscle and gonad was paired with a decline in weight of those two organs, especially when the control groups are considered, but a decrease was also evident for the triploid groups. This may have been caused by the presence of El Niño, with its characteristic high water temperatures and low productivity.

20.
Rev Med Chil ; 127(7): 827-30, 1999 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-10668291

RESUMO

We report a 66 years old male, with an ophtalmologic history of long sightedness, admitted to the hospital due to paroxysmal atrial fibrillation crises in the context of a coronary heart disease. He was treated with i.v. amiodarone, receiving a total dose of 6 g in 72 hours. After the third day of treatment, the patient noticed a correction of his long sightedness and 24 h later, he complained of hlurred vision and orbital frontal headache. Visual field examination revealed a concentric retraction of visual field and a centrocecal scotoma in both eyes. Amiodarone was withdrawn and dexametasone treatment was begun. Three days after amiodarone discontinuation, sight improved and visual field returned to normal. Although retrobulbar neuritis has been associated to various drugs, amiodarone has not been considered as a possible agent.


Assuntos
Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Neurite Óptica/induzido quimicamente , Idoso , Fibrilação Atrial/tratamento farmacológico , Humanos , Masculino , Taquicardia Paroxística/tratamento farmacológico
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