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1.
J Wildl Dis ; 57(2): 282-291, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33822153

RESUMO

In Norway, the Willow Ptarmigan (Lagopus lagopus lagopus) is experiencing population declines and is nationally Red Listed as Near Threatened. Although disease has not generally been regarded as an important factor behind population fluctuations for Willow Ptarmigan in Norway, disease occurrence has been poorly investigated. Both louping-ill virus (LIV) and the closely related tick-borne encephalitis virus are found along the southern part of the Norwegian coast. We assessed whether and where Norwegian Willow Ptarmigan populations have been infected with LIV. We expected to find infected individuals in populations in the southernmost part of the country. We did not expect to find infected individuals in populations further north and at higher altitudes because of the absence of the main vector, the sheep tick (Ixodes ricinus). We collected serum samples on Nobuto filter paper and used a hemagglutination inhibition assay for antibodies against LIV. We collected data at both local and country-wide levels. For local sampling, we collected and analyzed 87 hunter-collected samples from one of the southernmost Willow Ptarmigan populations in Norway. Of these birds, only three positives (3.4%) were found. For the country-wide sampling, we collected serum samples from 163 Willow Ptarmigan carcasses submitted from selected locations all over the country. Of these birds, 32% (53) were seropositive for LIV or a cross-reacting virus. Surprisingly, we found seropositive individuals from locations across the whole country, including outside the known distribution of the sheep tick. These results suggest that either LIV or a cross-reacting virus infects ptarmigan in large parts of Norway, including at high altitudes and latitudes.


Assuntos
Doenças das Aves/virologia , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Galliformes , Meningoencefalomielite Ovina/sangue , Animais , Doenças das Aves/epidemiologia , Meningoencefalomielite Ovina/epidemiologia , Noruega/epidemiologia , Estudos Soroepidemiológicos , Testes Sorológicos , Ovinos
2.
BMC Ecol ; 18(1): 41, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30285717

RESUMO

BACKGROUND: Habitat models provide information about which habitat management should target to avoid species extinctions or range contractions. The willow ptarmigan inhabits alpine- and arctic tundra habitats in the northern hemisphere and is listed as near threatened (NT) in the Norwegian red list due to declining population size. Habitat alteration is one of several factors affecting willow ptarmigan populations, but there is a lack of studies quantifying and describing habitat selection in willow ptarmigan. We used data from an extensive line transect survey program from 2014 to 2017 to develop resource selection functions (RSF) for willow ptarmigan in Norway. The selection coefficients for the RSF were estimated using a mixed-effects logistic regression model fitted with random intercepts for each area. We predicted relative probability of selection across Norway and quantile-binned the predictions in 10 RSF bins ranging from low-(1) to high-(10) relative probability of selection. RESULTS: Random cross-validation suggest that our models were highly predictive, but validation based spatial blocking revealed that the predictability was better in southern parts of Norway compared to the northernmost region. Willow ptarmigan selected for herb-rich meadows and avoided lichen rich heathlands. There was generally stronger selection for vegetation types with dense field layer and for rich bogs and avoidance of vegetation types with sparse field layer cover and for lowland forest. Further, willow ptarmigan selected for areas around the timberline and for intermediate slopes. Mapping of the RSF showed that 60% of Norway is in the lowest ranked RSF bin and only 2% in the highest ranked RSF bin. CONCLUSIONS: Willow ptarmigan selected for vegetation types with dense field layer and bogs at intermediate slopes around the timberline. Selection coincides with previous habitat selection studies on willow ptarmigan. This is the first attempt to assess and quantify habitat selection for willow ptarmigan at a large scale using data from line transect distance sampling surveys. Spatial variation in predictability suggests that habitat selection in late summer might vary from north to south. The resource selection map can be a useful tool when planning harvest quotas and habitat interventions in alpine areas.


Assuntos
Ecossistema , Galliformes/fisiologia , Animais , Modelos Biológicos , Noruega , Densidade Demográfica , Estações do Ano
3.
Bioconjug Chem ; 25(6): 1036-42, 2014 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-24852797

RESUMO

Novel reporters have been synthesized with extended hydrophilic linkers that in combination with polymerizing cross-linkers result in very efficient reporter deposition. By utilizing antibodies to stain HER2 proteins in a cell line model it is demonstrated that the method is highly specific and sensitive with virtually no background. The detection of HER2 proteins in tissue was used to visualize individual antigens as small dots visible in a microscope. Image analysis-assisted counting of fluorescent or colored dots allowed assessment of relative protein levels in tissue. Taken together, we have developed novel reporters that improve the CARD method allowing highly sensitive in situ detection of proteins in tissue. Our findings suggest that in situ protein quantification in biological samples can be performed by object recognition and enumeration of dots, rather than intensity-based fluorescent or colorimetric assays.


Assuntos
Anticorpos/metabolismo , Benzidinas/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Receptor ErbB-2/análise , Anticorpos/química , Benzidinas/química , Biocatálise , Linhagem Celular Tumoral , Reagentes de Ligações Cruzadas/síntese química , Reagentes de Ligações Cruzadas/química , Peroxidase do Rábano Silvestre/química , Humanos , Estrutura Molecular , Receptor ErbB-2/biossíntese
4.
Hum Pathol ; 45(3): 522-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24457075

RESUMO

In some tumors, phosphatase and tensin homolog (PTEN) inactivation may have prognostic importance and predictive value for targeted therapies. Immunohistochemistry (IHC) may be an effective method to demonstrate PTEN loss. It was claimed that PTEN IHC showed poor reproducibility, lack of standardization, and variable effects of preanalytical factors. In this study, we developed an optimal protocol for PTEN IHC, with clone 6H2.1, by checking the relevance of analytical variables in normal tissue and tumors of endometrium, breast, and prostate. Pattern and intensity of cellular staining and background nonspecific staining were quantified and subjected to statistical analysis by linear mixed models. The proposed protocol showed a statistically best performance (P < .05) and included a high target retrieval solution, 1:100 primary antibody dilution (2.925 mg/L), FLEX diluent, and EnVisionFLEX+ detection method, with a sensitivity and specificity of 72.33% and 78.57%, respectively. Staining specificity was confirmed in cell lines and animal models. Endometrial carcinomas with PTEN genetic abnormalities showed statistically lower staining than tumors without alterations (mean histoscores, 34.66 and 119.28, respectively; P = .01). Controlled preanalytical factors (delayed fixation and overfixation) did not show any statistically significant effect on staining with optimal protocol (P > .001). However, there was a trend of significance for decreased staining and fixation under high temperature. Moreover, staining was better in endometrial aspirates than in matched hysterectomy specimens, subjected to less controlled preanalytical variables (mean histoscores, 80 and 40, respectively; P = .002). A scoring system combining intensity of staining and percentage of positive cells was statistically associated with PTEN alterations (P = .01).


Assuntos
Mama/química , Endométrio/química , Imuno-Histoquímica/métodos , PTEN Fosfo-Hidrolase/análise , Próstata/química , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/metabolismo , Endométrio/patologia , Feminino , Humanos , Masculino , PTEN Fosfo-Hidrolase/metabolismo , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes
5.
Oecologia ; 173(3): 813-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23636461

RESUMO

Home range size in mammals is a key ecological trait and an important parameter in conservation planning, and has been shown to be influenced by ecological, demographic and social factors in animal populations. Information on space requirements is especially important for carnivore species which range over very large areas and often come into direct conflict with human interest. We used long-term telemetry-location data from a recovering wolf population in Scandinavia to investigate variation in home range size in relation to environmental and social characteristics of the different packs. Wolves showed considerable variation in home range size, which ranged from 259 to 1,676 km(2). Although wolf density increased fourfold during the study period, we found no evidence that intraspecific competition influenced range size. Local variation in moose density, which was the main prey for most packs, did not influence wolf home range size. Home ranges increased with latitude and elevation and decreased with increased roe deer density. Although prey biomass alone did not influence range size, our data suggest that there is a correlation between habitat characteristics, choice of prey species and possible hunting success, which currently combine to shape home range size in Scandinavian wolves.


Assuntos
Conservação dos Recursos Naturais/métodos , Meio Ambiente , Comportamento de Retorno ao Território Vital/fisiologia , Lobos/fisiologia , Animais , Dinâmica Populacional , Países Escandinavos e Nórdicos , Telemetria , Fatores de Tempo
6.
Proc Biol Sci ; 279(1730): 910-5, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21849323

RESUMO

Poaching is a widespread and well-appreciated problem for the conservation of many threatened species. Because poaching is illegal, there is strong incentive for poachers to conceal their activities, and consequently, little data on the effects of poaching on population dynamics are available. Quantifying poaching mortality should be a required knowledge when developing conservation plans for endangered species but is hampered by methodological challenges. We show that rigorous estimates of the effects of poaching relative to other sources of mortality can be obtained with a hierarchical state-space model combined with multiple sources of data. Using the Scandinavian wolf (Canis lupus) population as an illustrative example, we show that poaching accounted for approximately half of total mortality and more than two-thirds of total poaching remained undetected by conventional methods, a source of mortality we term as 'cryptic poaching'. Our simulations suggest that without poaching during the past decade, the population would have been almost four times as large in 2009. Such a severe impact of poaching on population recovery may be widespread among large carnivores. We believe that conservation strategies for large carnivores considering only observed data may not be adequate and should be revised by including and quantifying cryptic poaching.


Assuntos
Espécies em Perigo de Extinção , Modelos Teóricos , Lobos , Animais , Europa (Continente) , Atividades Humanas , Humanos , Cadeias de Markov , Método de Monte Carlo , Densidade Demográfica , Dinâmica Populacional
7.
Histopathology ; 59(5): 975-83, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22092409

RESUMO

AIMS: The availability of specific antibody-based test systems is essential to testing of HER2 protein expression. Here, we mapped epitopes recognized by three pharmacodiagnostic HER2 antibodies and investigated their specificity towards peptides and fusion proteins homologous to the intracellular domains of HER1, HER2, HER3 and HER4. The investigated antibodies were PATHWAY(®) HER2 (clone 4B5; Ventana Medical Systems Inc., Tucson, AZ, USA), HercepTest™ (Dako Denmark A/S, Glostrup, Denmark), and Oracle(®) HER2 (clone CB11; Leica Microsystems GmbH, Wetzlar, Germany). METHODS AND RESULTS: Epitopes were mapped using the alanine scanning method. Specificity was investigated in immunohistochemical stainings, competitive enzyme-linked immunosorbent assay (ELISA) and immunoblotting. All three antibodies reacted with HER2 proteins and peptides in immunohistochemical stainings, ELISA and immunoblotting. PATHWAY(®) HER2 also stained HER4-expressing cells, reacted with HER4 peptide in ELISA and detected HER4 fusion protein in an immunoblot. Oracle(®) HER2 weakly detected HER4 in immunohistochemical stainings, whereas the HercepTest™ antibody showed no cross-reactivity with other HER proteins. CONCLUSION: Our study shows that the PATHWAY(®) HER2 antibody can bind HER4 peptides and fusion proteins in three different experimental settings. This should be investigated further to determine whether binding of HER4 also occurs in tissue samples and if such binding would have implications for therapy decisions for breast cancer patients.


Assuntos
Anticorpos Monoclonais , Especificidade de Anticorpos , Neoplasias da Mama/metabolismo , Receptor ErbB-2/análise , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Receptores ErbB/análise , Receptores ErbB/química , Receptores ErbB/imunologia , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Receptor ErbB-2/química , Receptor ErbB-2/imunologia , Receptor ErbB-4
8.
PLoS One ; 6(4): e18930, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21526118

RESUMO

The magnitude and urgency of the biodiversity crisis is widely recognized within scientific and political organizations. However, a lack of integrated measures for biodiversity has greatly constrained the national and international response to the biodiversity crisis. Thus, integrated biodiversity indexes will greatly facilitate information transfer from science toward other areas of human society. The Nature Index framework samples scientific information on biodiversity from a variety of sources, synthesizes this information, and then transmits it in a simplified form to environmental managers, policymakers, and the public. The Nature Index optimizes information use by incorporating expert judgment, monitoring-based estimates, and model-based estimates. The index relies on a network of scientific experts, each of whom is responsible for one or more biodiversity indicators. The resulting set of indicators is supposed to represent the best available knowledge on the state of biodiversity and ecosystems in any given area. The value of each indicator is scaled relative to a reference state, i.e., a predicted value assessed by each expert for a hypothetical undisturbed or sustainably managed ecosystem. Scaled indicator values can be aggregated or disaggregated over different axes representing spatiotemporal dimensions or thematic groups. A range of scaling models can be applied to allow for different ways of interpreting the reference states, e.g., optimal situations or minimum sustainable levels. Statistical testing for differences in space or time can be implemented using Monte-Carlo simulations. This study presents the Nature Index framework and details its implementation in Norway. The results suggest that the framework is a functional, efficient, and pragmatic approach for gathering and synthesizing scientific knowledge on the state of biodiversity in any marine or terrestrial ecosystem and has general applicability worldwide.


Assuntos
Biodiversidade , Conhecimento , Natureza , Cidades , Ecossistema , Humanos , Modelos Biológicos , Noruega , Padrões de Referência , Incerteza
9.
Breast Cancer Res ; 12(4): R47, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20615243

RESUMO

INTRODUCTION: Patients with early-stage breast cancer, treated with endocrine therapy, have approximately 90% 5-year disease-free survival. However, for patients at higher risk of relapse despite endocrine therapy, additional adjuvant therapy, such as chemotherapy, may be indicated. The challenge is to prospectively identify such patients. The Mammostrat® test uses five immunohistochemical markers to stratify patients on tamoxifen therapy into risk groups to inform treatment decisions. We tested the efficacy of this panel in a mixed population of cases treated in a single center with breast-conserving surgery and long-term follow-up. METHODS: Tissue microarrays from a consecutive series (1981 to 1998) of 1,812 women managed by wide local excision and postoperative radiotherapy were collected following appropriate ethical review. Of 1,390 cases stained, 197 received no adjuvant hormonal or chemotherapy, 1,044 received tamoxifen only, and 149 received a combination of hormonal therapy and chemotherapy. Median age at diagnosis was 57, 71% were postmenopausal, 23.9% were node-positive and median tumor size was 1.5 cm. Samples were stained using triplicate 0.6 mm2 tissue microarray cores, and positivity for p53, HTF9C, CEACAM5, NDRG1 and SLC7A5 was assessed. Each case was assigned a Mammostrat risk score, and distant recurrence-free survival (DRFS), relapse-free survival (RFS) and overall survival (OS) were analyzed by marker positivity and risk score. RESULTS: Increased Mammostrat scores were significantly associated with reduced DRFS, RFS and OS in estrogen receptor (ER)-positive breast cancer (P < 0.00001). In multivariate analyses the risk score was independent of conventional risk factors for DRFS, RFS and OS (P < 0.05). In node-negative, tamoxifen-treated patients, 10-year recurrence rates were 7.6 ± 1.5% in the low-risk group versus 20.0 ± 4.4% in the high-risk group. Further, exploratory analyses revealed associations with outcome in both ER-negative and untreated patients. CONCLUSIONS: This is the fifth independent study providing evidence that Mammostrat can act as an independent prognostic tool for ER-positive, tamoxifen-treated breast cancer. In addition, this study revealed for the first time a possible association with outcome regardless of node status and ER-negative tumors. When viewed in the context of previous results, these data provide further support for this antibody panel as an aid to patient management in early-stage breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Testes Diagnósticos de Rotina/métodos , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Antígeno Carcinoembrionário/metabolismo , Proteínas de Ciclo Celular/metabolismo , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Proteínas Ligadas por GPI/metabolismo , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Prognóstico , Receptores de Estrogênio/metabolismo , Reprodutibilidade dos Testes , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade , Tamoxifeno/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo
10.
Histopathology ; 55(6): 724-31, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19845790

RESUMO

AIMS: To assess the validity of grading in the Edinburgh Breast Conservation Series; a consecutive cohort of 1812 early breast cancer patients treated by breast conservation and radiotherapy between 1981 and 1998 in a single specialist centre with > or =9 years' follow-up and full staging data. METHODS AND RESULTS: A single pathologist (J.St.J.T) graded 1650 cases using the Elston and Ellis method (EE) with particular reference to the component data: acinar differentiation, nuclear pleomorphism and mitotic counts. The original method was then compared with binary scoring of the same components and the relationship to prognosis reassessed. EE grades and individual grade components were prognostic (P < 0.0001) with 10-year cause-specific survival of 95.6%, 86.4% and 74.7% for EE grades 1, 2 and 3, respectively. A binary scoring of grade components produces four groups, splitting EE grade 2 tumours into two groups with different outcomes--10-year survival rates for the four revised grades were 96.0%, 89.0%, 79.7% and 75.4%, respectively. CONCLUSIONS: Existing grading methodology is fully applicable in the narrower context of a conservation series but can be simplified. Subdivision of EE grade 2 into a true intermediate prognosis group and a second group with a worse prognosis also adds benefit.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Feminino , Humanos , Metástase Linfática , Mitose , Estadiamento de Neoplasias , Prognóstico , Índice de Gravidade de Doença , Taxa de Sobrevida
11.
J Biomol Screen ; 11(4): 423-34, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16751337

RESUMO

The RAS-mitogen-activated protein kinase (MAPK) signaling pathway has a central role in regulating the proliferation and survival of both normal and tumor cells. This pathway has been 1 focus area for the development of anticancer drugs, resulting in several compounds, primarily kinase inhibitors, in clinical testing. The authors have undertaken a cell-based, high-throughput screen using a novel ERF1 Redistribution assay to identify compounds that modulate the signaling pathway. The hit compounds were subsequently tested for activity in a functional cell proliferation assay designed to selectively detect compounds inhibiting the proliferation of MAPK pathway-dependent cancer cells. The authors report the identification of 2 cell membrane-permeable compounds that exhibit activity in the ERF1 Redistribution assay and selectively inhibit proliferation of MAPK pathway-dependent malignant melanoma cells at similar potencies (IC(50)=< 5 microM). These compounds have drug-like structures and are negative in RAF, MEK, and ERK in vitro kinase assays. Drugs belonging to these compound classes may prove useful for treating cancers caused by excessive MAPK pathway signaling. The results also show that cell-based, high-content Redistribution screens can detect compounds with different modes of action and reveal novel targets in a pathway known to be disease relevant.


Assuntos
Proteínas de Ligação a DNA/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos/métodos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Repressoras/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cricetinae , Proteínas de Ligação a DNA/genética , Humanos , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases/genética , Estrutura Molecular , Fosforilação , RNA Interferente Pequeno/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Transfecção
12.
Comb Chem High Throughput Screen ; 8(4): 301-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16101006

RESUMO

G protein-coupled receptors (GPCRs) have been one of the most productive classes of drug targets for several decades, and new technologies for GPCR-based discovery promise to keep this field active for years to come. While molecular screens for GPCR receptor agonist- and antagonist-based drugs will continue to be valuable discovery tools, the most exciting developments in the field involve cell-based assays for GPCR function. Some cell-based discovery strategies, such as the use of beta-arrestin as a surrogate marker for GPCR function, have already been reduced to practice, and have been used as valuable discovery tools for several years. The application of high content cell-based screening to GPCR discovery has opened up additional possibilities, such as direct tracking of GPCRs, G proteins and other signaling pathway components using intracellular translocation assays. These assays provide the capability to probe GPCR function at the cellular level with better resolution than has previously been possible, and offer practical strategies for more definitive selectivity evaluation and counter-screening in the early stages of drug discovery. The potential of cell-based translocation assays for GPCR discovery is described, and proof-of-concept data from a pilot screen with a CXCR4 assay are presented. This chemokine receptor is a highly relevant drug target which plays an important role in the pathogenesis of inflammatory disease and also has been shown to be a co-receptor for entry of HIV into cells as well as to play a role in metastasis of certain cancer cells.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Transporte Proteico , Receptores Acoplados a Proteínas G/metabolismo , Animais , Bioensaio , Neoplasias Ósseas , Brefeldina A/farmacologia , Células COS , Quimiocina CXCL12 , Quimiocinas CXC/metabolismo , Quimiocinas CXC/farmacologia , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Osteossarcoma , Receptores CXCR4/agonistas , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Sensibilidade e Especificidade , Células Tumorais Cultivadas
13.
J Biomol Screen ; 10(1): 20-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15695340

RESUMO

The PI3-kinase/Akt pathway is an important cell survival pathway that is deregulated in the majority of human cancers. Despite the apparent druggability of several kinases in the pathway, no specific catalytic inhibitors have been reported in the literature. The authors describe the development of a fluorometric imaging plate reader (FLIPR)-based Akt1 translocation assay to discover inhibitors of Akt1 activation. Screening of a diverse chemical library of 45,000 compounds resulted in identification of several classes of Akt1 translocation inhibitors. Using a combination of classical in vitro assays and translocation assays directed at different steps of the Akt pathway, the mechanisms of action of 2 selected chemical classes were further defined. Protein translocation assays emerge as powerful tools for hit identification and characterization.


Assuntos
Avaliação Pré-Clínica de Medicamentos/instrumentação , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Células CHO , Linhagem Celular Tumoral , Cricetinae , Fluorometria , Humanos , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/química , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt
14.
Spine (Phila Pa 1976) ; 30(2): 206-8, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15644757

RESUMO

STUDY DESIGN: Classic twin study. OBJECTIVES: To determine the heritability of neck pain in persons 70 years of age and older. SUMMARY OF BACKGROUND DATA: Previous studies have shown a moderate effect of genetic factors on back pain in the elderly. Genetic influence on neck pain in old age is unknown. METHODS: Data on the 1-month prevalence of neck pain from twin pairs participating in the population based Longitudinal Study of Aging Danish Twins formed the basis of this analysis. To assess twin similarity, probandwise concordance rates, odds ratios, and tetrachoric correlations were calculated and compared for monozygotic and dizygotic twins. Further, heritability estimates were calculated using bivariate probit estimation. RESULTS: A total of 2,108 twin individuals, including 1,054 complete twin pairs, answered the question related to neck pain at intake into the Longitudinal Study of Aging Danish Twins study. Low and nonsignificant probandwise concordance rates, odds ratios, and tetrachoric correlations were found for both men and women in monozygotic and dizygotic twin pairs, indicating small or negligible genetic effects. Heritability estimates adjusted for age and significant environmental risk factors (rheumatoid arthritis, osteoarthritis, disc prolapse, and coronary heart disease) showed no significant additive genetic, dominant genetic, or common environmental effects. CONCLUSION: Genetic factors do not play an important role in the liability to neck pain in persons 70 years of age or older.


Assuntos
Envelhecimento , Doenças em Gêmeos/genética , Predisposição Genética para Doença/epidemiologia , Cervicalgia/genética , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Dinamarca/epidemiologia , Meio Ambiente , Feminino , Humanos , Estudos Longitudinais , Masculino , Cervicalgia/epidemiologia , Cervicalgia/fisiopatologia , Razão de Chances , Gêmeos Dizigóticos , Gêmeos Monozigóticos
15.
Biol Lett ; 1(1): 17-20, 2005 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-17148117

RESUMO

The difficulty of obtaining pedigrees for wild populations has hampered the possibility of demonstrating inbreeding depression in nature. In a small, naturally restored, wild population of grey wolves in Scandinavia, founded in 1983, we constructed a pedigree for 24 of the 28 breeding pairs established in the period 1983-2002. Ancestry for the breeding animals was determined through a combination of field data (snow tracking and radio telemetry) and DNA microsatellite analysis. The population was founded by only three individuals. The inbreeding coefficient F varied between 0.00 and 0.41 for wolves born during the study period. The number of surviving pups per litter during their first winter after birth was strongly correlated with inbreeding coefficients of pups (R2=0.39, p<0.001). This inbreeding depression was recalculated to match standard estimates of lethal equivalents (2B), corresponding to 6.04 (2.58-9.48, 95% CI) litter-size-reducing equivalents in this wolf population.


Assuntos
Endogamia , Lobos/fisiologia , Animais , Conservação dos Recursos Naturais , Tamanho da Ninhada de Vivíparos/genética , Repetições de Microssatélites , Linhagem , Dinâmica Populacional , Países Escandinavos e Nórdicos , Lobos/genética
16.
Spine (Phila Pa 1976) ; 29(8): 897-901; discussion 902, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15082992

RESUMO

STUDY DESIGN: Self-reported 1-month prevalence of back pain in older twins assessed at intake in a population-based longitudinal survey. OBJECTIVES: To determine the relative contribution of genetic and environmental factors to back pain in old age. SUMMARY OF BACKGROUND DATA: To date, genetic contributions to back pain in old age have not been assessed, to the authors' best knowledge. METHODS: Interview data given at entry into a nationwide cohort-sequential population-based survey of Danish twins aged 70 years and older in 1995, 1997, 1999, and 2001 form the basis of this analysis. Analysis of twin similarity was estimated using probandwise concordance rates, odds ratios, and tetrachoric correlations for back pain. Heritability (proportion of the population variance attributable to genetic variation) was estimated by bivariate probit estimation and adjusted for known significant environmental factors. Odds ratios for known environmental effects were estimated after controlling for age, sex, and genetic effects. RESULTS: Modest and nonsignificant differences between monozygotic and dizygotic twin pairs were found for probandwise concordance rates, odds ratios, and tet-rachoric correlations for both men and women. In the bivariate probit estimation, a current or previous diagnosis of osteoporosis, degenerative joint disease, or lumbar disc prolapse was found to significantly affect the risk of back pain. Additive genetic effects explained approximately one fourth of the liability to report back pain in men and none of the occurrence in women. Individual environmental effects were found to explain roughly 75% of the occurrence of back pain in men and 100% in women. CONCLUSIONS: Additive genetic effects are modest contributors to back pain in older men but not in women. A current or previous medical diagnosis of osteoporosis, degenerative joint disease, or lumbar disc prolapse is-strongly associated with back pain, also when genetic factors are controlled for. Because of inherent methodologic issues, this estimate of the genetic influence on back pain in old age is probably conservative.


Assuntos
Dor nas Costas/epidemiologia , Dor nas Costas/genética , Meio Ambiente , Predisposição Genética para Doença/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Dinamarca/epidemiologia , Feminino , Humanos , Deslocamento do Disco Intervertebral/epidemiologia , Deslocamento do Disco Intervertebral/genética , Entrevistas como Assunto , Artropatias/epidemiologia , Artropatias/genética , Estudos Longitudinais , Região Lombossacral , Masculino , Modelos Estatísticos , Razão de Chances , Osteoporose/epidemiologia , Osteoporose/genética , Distribuição por Sexo , Fatores Sexuais , Gêmeos Dizigóticos , Gêmeos Monozigóticos
17.
Evolution ; 44(6): 1490-1497, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28564303

RESUMO

We examined eight polymorphic esterase loci in 526 juvenile and adult willow ptarmigan (Lagopus lagopus lagopus) collected during autumn and spring over five years. The genetic structure of territorial birds during spring differed from birds on the study area in autumn. This can not be explained by selective winter mortality since juvenile birds in the autumn had the same genetic structure as the adults who had lived through at least one winter. In the spring, birds with intermediate heterozygosity had the largest territories and were more frequently mated than expected from random mating among autumn birds. The results suggest selective access to territories by genotype and stabilizing selection, especially among males, since natural selection is assumed to favor large territories and reproduction. Our data also suggest that the spring population consisted of both territorial and non-territorial birds. The genetic relationship between birds of established pairs in spring was lower than that between randomly drawn birds on the study area in the autumn. This together with the finding that parents with an intermediate level of genetic relationship produced the largest broods, suggest that optimal rather than maximal outbreeding is the most successful breeding strategy in this species.

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