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1.
Sci Rep ; 10(1): 16050, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994491

RESUMO

Independent studies have observed that a paternal history of stress or trauma is associated with his children having a greater likelihood of developing psychopathologies such as anxiety disorders. This father-to-child effect is reproduced in several mouse models of stress, which have been crucial in developing a greater understanding of intergenerational epigenetic inheritance. We previously reported that treatment of C57Bl/6J male breeders with low-dose corticosterone (CORT) for 28 days prior to mating yielded increased anxiety-related behaviours in their male F1 offspring. The present study aimed to determine whether subchronic 7-day CORT treatment of male mice just prior to mating would be sufficient to induce intergenerational modifications of anxiety-related behaviours in offspring. We report that subchronic CORT treatment of male breeders reduced their week-on-week body weight gain and altered NR3C1 and CRH gene expression in the hypothalamus. There were no effects on sperm count and glucocorticoid receptor protein levels within the epididymal tissue of male breeders. Regarding the F1 offspring, screening for anxiety-related behaviours using the elevated-plus maze, light-dark box, and novelty-suppressed feeding test revealed no differences between the offspring of CORT-treated breeders compared to controls. Thus, it is crucial that future studies take into consideration the duration of exposure when assessing the intergenerational impacts of paternal health.


Assuntos
Ansiedade/etiologia , Ansiedade/metabolismo , Herança Paterna/genética , Animais , Transtornos de Ansiedade/etiologia , Transtornos de Ansiedade/genética , Comportamento Animal/efeitos dos fármacos , Corticosterona/metabolismo , Corticosterona/farmacologia , Hormônio Liberador da Corticotropina/efeitos dos fármacos , Hormônio Liberador da Corticotropina/genética , Epigênese Genética/efeitos dos fármacos , Pai , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/genética , Estresse Psicológico/metabolismo
2.
J Am Assoc Nurse Pract ; 33(1): 20-28, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31738274

RESUMO

BACKGROUND: Chronic migraine is a primary headache disorder affecting approximately 3-7 million individuals in the United States. This condition is associated with significant individual and societal consequences, causing impaired function and high levels of health care utilization. PURPOSE: The aim of this quasi-experimental single cohort study was to determine if an 8-week outpatient self-management program for chronic migraine would decrease migraine disability and enhance self-efficacy. METHODS: This was a prospective, single cohort, pre- and postintervention pilot study. Fifteen adults aged 18-65 years who met the criteria for diagnosis of chronic migraine were enrolled in the study through convenience sampling. Participants participated in an evidence-based self-management program with multimodal formats including verbal, written, video, and online materials. Outcome measures included migraine disability (using Migraine Disability Assessment tool [MIDAS]), headache self-efficacy (using Headache Management Self-Efficacy Scale [HMSE]), acute medication use, and migraine frequency. Participants also completed a postintervention survey to assess satisfaction. RESULTS: Findings showed a reduction in MIDAS scores, acute medication use, and frequency of migraine. Outcomes also included an increase in HMSE scores and a trend of improved health behaviors. Acute medication use decreased by more than 50%, and frequency of migraine and headache days reduced by close to 40%. IMPLICATIONS FOR PRACTICE: Despite high rates of disability, patient education and self-management programs for chronic migraine are not readily available. The findings of this study encourage use of a hybrid clinic and web-based self-management model to improve migraine disability and self-efficacy.


Assuntos
Pessoas com Deficiência/classificação , Transtornos de Enxaqueca/terapia , Autoeficácia , Autogestão/métodos , Adulto , Estudos de Coortes , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/psicologia , Projetos Piloto , Estudos Prospectivos , Teoria Psicológica , Autogestão/psicologia , Autogestão/estatística & dados numéricos
3.
Transl Psychiatry ; 7(5): e1114, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28463242

RESUMO

There is growing evidence that the preconceptual lifestyle and other environmental exposures of a father can significantly alter the physiological and behavioral phenotypes of their children. We and others have shown that paternal preconception stress, regardless of whether the stress was experienced during early-life or adulthood, results in offspring with altered anxiety and depression-related behaviors, attributed to hypothalamic-pituitary-adrenal axis dysregulation. The transgenerational response to paternal preconceptual stress is believed to be mediated by sperm-borne small noncoding RNAs, specifically microRNAs. As physical activity confers physical and mental health benefits for the individual, we used a model of voluntary wheel-running and investigated the transgenerational response to paternal exercise. We found that male offspring of runners had suppressed reinstatement of juvenile fear memory, and reduced anxiety in the light-dark apparatus during adulthood. No changes in these affective behaviors were observed in female offspring. We were surprised to find that running had a limited impact on sperm-borne microRNAs. The levels of three unique microRNAs (miR-19b, miR-455 and miR-133a) were found to be altered in the sperm of runners. In addition, we discovered that the levels of two species of tRNA-derived RNAs (tDRs)-tRNA-Gly and tRNA-Pro-were also altered by running. Taken together, we believe this is the first evidence that paternal exercise is associated with an anxiolytic behavioral phenotype of male offspring and altered levels of small noncoding RNAs in sperm. These small noncoding RNAs are known to have an impact on post-transcriptional gene regulation and can thus change the developmental trajectory of offspring brains and associated affective behaviors.


Assuntos
Ansiedade/genética , Medo/psicologia , Transmissão Vertical de Doenças Infecciosas/veterinária , MicroRNAs/genética , Condicionamento Físico Animal/efeitos adversos , Espermatozoides/metabolismo , Animais , Ansiedade/psicologia , Depressão/genética , Depressão/psicologia , Exposição Ambiental/efeitos adversos , Feminino , Regulação da Expressão Gênica , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Sistema Hipófise-Suprarrenal/fisiopatologia , Pequeno RNA não Traduzido
4.
Transl Psychiatry ; 6(6): e837, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27300263

RESUMO

Recent studies have suggested that physiological and behavioral traits may be transgenerationally inherited through the paternal lineage, possibly via non-genomic signals derived from the sperm. To investigate how paternal stress might influence offspring behavioral phenotypes, a model of hypothalamic-pituitary-adrenal (HPA) axis dysregulation was used. Male breeders were administered water supplemented with corticosterone (CORT) for 4 weeks before mating with untreated female mice. Female, but not male, F1 offspring of CORT-treated fathers displayed altered fear extinction at 2 weeks of age. Only male F1 offspring exhibited altered patterns of ultrasonic vocalization at postnatal day 3 and, as adults, showed decreased time in open on the elevated-plus maze and time in light on the light-dark apparatus, suggesting a hyperanxiety-like behavioral phenotype due to paternal CORT treatment. Interestingly, expression of the paternally imprinted gene Igf2 was increased in the hippocampus of F1 male offspring but downregulated in female offspring. Male and female F2 offspring displayed increased time spent in the open arm of the elevated-plus maze, suggesting lower levels of anxiety compared with control animals. Only male F2 offspring showed increased immobility time on the forced-swim test and increased latency to feed on the novelty-supressed feeding test, suggesting a depression-like phenotype in these animals. Collectively, these data provide evidence that paternal CORT treatment alters anxiety and depression-related behaviors across multiple generations. Analysis of the small RNA profile in sperm from CORT-treated males revealed marked effects on the expression of small noncoding RNAs. Sperm from CORT-treated males contained elevated levels of three microRNAs, miR-98, miR-144 and miR-190b, which are predicted to interact with multiple growth factors, including Igf2 and Bdnf. Sustained elevation of glucocorticoids is therefore involved in the transmission of paternal stress-induced traits across generations in a process involving small noncoding RNA signals transmitted by the male germline.


Assuntos
Ansiedade/genética , Corticosterona/farmacologia , Depressão/genética , Sistema Hipotálamo-Hipofisário/fisiopatologia , Exposição Paterna , Fenótipo , Sistema Hipófise-Suprarrenal/fisiopatologia , Pequeno RNA não Traduzido/genética , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Animais , Ansiedade/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão/fisiopatologia , Éxons , Medo/efeitos dos fármacos , Medo/fisiologia , Feminino , Expressão Gênica/genética , Expressão Gênica/fisiologia , Fator de Crescimento Insulin-Like II/genética , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Gravidez , Fatores Sexuais
5.
Genes Immun ; 16(6): 430-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26204230

RESUMO

In common with several other autoimmune diseases, autoimmune Addison's disease (AAD) is thought to be caused by a combination of deleterious susceptibility polymorphisms in several genes, together with undefined environmental factors and stochastic events. To date, the strongest genomic association with AAD has been with alleles at the HLA locus, DR3-DQ2 and DR4. The contribution of other genetic variants has been inconsistent. We have studied the association of 16 single-nucleotide polymorphisms (SNPs) within the CD28-CTLA-4-ICOS genomic locus, in a cohort comprising 691 AAD patients of Norwegian and UK origin with matched controls. We have also performed a meta-analysis including 1002 patients from European countries. The G-allele of SNP rs231775 in CTLA-4 is associated with AAD in Norwegian patients (odds ratio (OR)=1.35 (confidence interval (CI) 1.10-1.66), P=0.004), but not in UK patients. The same allele is associated with AAD in the total European population (OR=1.37 (CI 1.13-1.66), P=0.002). A three-marker haplotype, comprising PROMOTER_1661, rs231726 and rs1896286 was found to be associated with AAD in the Norwegian cohort only (OR 2.43 (CI 1.68-3.51), P=0.00013). This study points to the CTLA-4 gene as a susceptibility locus for the development of AAD, and refines its mapping within the wider genomic locus.


Assuntos
Doença de Addison/genética , Antígeno CTLA-4/genética , Adulto , Feminino , Estudos de Associação Genética , Determinismo Genético , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
6.
Am J Transplant ; 15(9): 2378-86, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26147285

RESUMO

Obesity and end-stage renal disease (ESRD) are on the increase worldwide. Kidney transplantation is the treatment of choice for ESRD. However, obesity is considered a contraindication for transplantation. We investigated the effect of BMI on mortality in transplanted and patients remaining on the waiting list in the United Kingdom. We analyzed the UK Renal Registry (RR) and the National Health Service Blood and Transplant (NHSBT) Organ Donation and Transplantation data for patients listed from January 1, 2004 to December 31, 2010, with follow-up until December 31, 2011. Seventeen thousand six hundred eighty-one patients were listed during the study period, with BMI recorded for 13 526 (77%). One- and five-year patient survival was significantly better in all BMI bands (<18.5, 18.5-<25, 25-<30, 30-<35, 35-<40, and 40+kg/m(2) ) in the transplant group when compared to those who remained on the waiting list (p < 0.0001). The analyses were repeated excluding live donor transplants and the results were essentially the same. On analyses of patient survival with BMI as a continuous variable or using 5 kg weight bands, there was no cut-off observed in the higher BMI patients where there would be no benefit to transplantation. For transplanted patients (N = 8088), there was no difference in patient or graft survival between the defined BMI bands. Thus, irrespective of BMI, patient survival is improved if transplanted.


Assuntos
Índice de Massa Corporal , Sobrevivência de Enxerto/fisiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Taxa de Sobrevida , Reino Unido , Listas de Espera , Adulto Jovem
7.
Int J Clin Pract ; 69(1): 131-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25359317

RESUMO

AIMS: With the increasing evidence of adverse consequences because of low vitamin D levels on health demand for vitamin D, screening is increasing. The objective of the study was to assess whether parathyroid hormone (PTH) levels/bone profile is sufficient to identify patients with vitamin D insufficiency or deficiency, or whether vitamin D should be measured directly. METHODOLOGY: A total of 1560 serum specimens, with requests for 25-hydroxyvitamin D (25-OH vitamin D), calcium, phosphate, alkaline phosphatase (ALP), creatinine and PTH on the same sample were analysed at Salford Royal Hospital from November 2010 to November 2012. RESULTS: The prevalence of total vitamin D insufficiency or deficiency (defined as total 25-OH vitamin D < 50 nmol/l) was 62.9% (981/1560) overall, with males having higher proportions (67.2 vs. 59.3 per cent; χ(2) = 8.78, p = 0.003). There was no overall trend in mean serum adjusted calcium across categories of 25-OH vitamin D status but mean serum phosphate was significantly lower (F = 6.53, p < 0.0001) in patients with a 25-OH vitamin D level < 50 nmol/l. However in patients with vitamin D deficiency, a significant proportion had PTH, calcium, phosphate and alkaline phosphatase levels within the laboratory normal range. Even at a 25-OH vitamin D < 10 nmol/l, 71.6% had a normal PTH, 89.8% had normal serum calcium levels, 84.9% had normal phosphate levels and 81.6% had normal serum ALP. CONCLUSIONS: Therefore, despite the costs associated with the measurement of vitamin D, our findings show that no surrogate is adequate for screening for vitamin D deficiency.


Assuntos
Vitamina D/sangue , Biomarcadores/análise , Biomarcadores/sangue , Cálcio da Dieta/farmacologia , Feminino , Humanos , Masculino , Hormônio Paratireóideo/deficiência , Vitamina D/análise , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
9.
Anim Genet ; 45(4): 542-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24835129

RESUMO

Cranial cruciate ligament rupture (CCLR) is the most common cause of pelvic limb lameness in dogs. To investigate the genetic basis of canine CCLR, we conducted a genome-wide association study using a canine SNP array in Newfoundland pedigree dogs with and without CCLR (n = 96). We identified three main chromosomal regions of CCLR association (on chromosomes 1, 3 and 33). Each of these regions was confirmed by Sequenom genotyping in a further cohort of Newfoundlands (n = 271). The results, particularly SNPs identified in the SORCS2 and SEMA5B genes, suggest that there may be neurological pathways involved in susceptibility to canine CCLR.


Assuntos
Lesões do Ligamento Cruzado Anterior , Doenças do Cão/genética , Cães/lesões , Estudo de Associação Genômica Ampla/veterinária , Polimorfismo de Nucleotídeo Único , Animais , Doenças do Cão/epidemiologia , Especificidade da Espécie
10.
Diabet Med ; 31(2): 208-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24117620

RESUMO

AIMS: There are conflicting data on microvascular complications in coexisting Type 1 diabetes and coeliac disease. We compared complications rates in youth with or without coeliac disease and examined the association between gluten-free diet adherence and complications. METHODS: This was a comparative study of adolescents (2510 without coeliac disease, 129 with coeliac disease); 60 (47%) did not adhere to a gluten-free diet--defined as elevated anti-tissue transglutaminase or endomysial immunoglobulin A titres. Retinopathy was detected using 7-field fundal photography and albumin excretion rate by timed overnight urine collections, with early elevation defined as albumin excretion rate ≥ 7.5 µg/min. Logistic regression was used to examine the association between complications and explanatory variables, including coeliac disease vs. no coeliac disease, gluten-free diet adherence vs. non-adherence, diabetes duration and HbA1c . RESULTS: Median age at last assessment was 16.5 years. Those with coeliac disease vs. those without were younger at diabetes diagnosis (7.1 vs. 8.6 years, P < 0.001) and had longer diabetes duration (9.3 vs. 7.2 years, P < 0.001). HbA1c was lower in those with coeliac disease vs. those without (67 vs. 70 mmol/mol, 8.3 vs. 8.6%, P = 0.04) and adherence to a gluten-free diet vs. non-adherence (66 vs. 72 mmol/mol, 8.2 vs. 8.7%, P = 0.003). There were no differences in complication rates between those with coeliac disease vs. those without (retinopathy 22 vs. 23%, elevated albumin excretion rate 31 vs. 28%). Non-adherence to a gluten-free diet was associated with elevated albumin excretion rate (40 vs. 23%, P = 0.04). In multivariable logistic regression, elevated albumin excretion rate was associated with non-adherence to a gluten-free diet (odds ratio 2.37, 95% CI 1.04-5.40, P = 0.04) and diabetes duration (odds ratio 1.13, 95% CI 1.02-1.25, P = 0.03), but not HbA1c . CONCLUSIONS: While glycaemic control is better in patients with coeliac disease, non-adherence to a gluten-free diet is associated with elevated albumin excretion rate. The possible protection of a gluten-free diet on complications warrants further investigation.


Assuntos
Albuminas/metabolismo , Albuminúria/epidemiologia , Doença Celíaca/dietoterapia , Doença Celíaca/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Dieta Livre de Glúten , Cooperação do Paciente/estatística & dados numéricos , Adolescente , Albuminúria/sangue , Albuminúria/etiologia , Albuminúria/urina , Doença Celíaca/complicações , Doença Celíaca/metabolismo , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino
11.
Diabet Med ; 29(9): e286-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22672045

RESUMO

AIMS: To determine the incidence of coeliac disease in young people with Type 1 diabetes and to examine the effect of age at diabetes onset and disease duration. METHODS: This was a clinic-based observational cohort study of 4379 people aged ≤ 18 years (49% male) between 1990 and 2009 from Sydney, Australia. Screening for coeliac disease was performed at diagnosis and 1-2 yearly using anti-endomysial and/or anti-tissue transglutaminase immunoglobulin A (IgA) antibodies. Coeliac disease was diagnosed by small bowel biopsy based on Marsh score ≥ III. RESULTS: Coeliac disease was confirmed by biopsy in 185; of these, 61 (33%) were endomysial or tissue transglutaminase IgA antibody-positive at diabetes diagnosis. Mean age at diabetes onset was 6.6 ± 4.0 vs. 8.4 ± 4.1 years in those without coeliac disease (P < 0.001). Mean incidence was 7.7 per 1000 person years (95% CI 6.6-8.9) over 20 years. Incidence was higher in children aged < 5 years at diabetes diagnosis (10.4 per 1000 person years) vs. ≥ 5 years (6.4 per 1000), incidence rate ratio 1.6 (95% CI 1.2-2.2, P = 0.002). Coeliac disease was diagnosed after 2, 5 and 10 years of diabetes in 45, 78 and 94% of cases, respectively. Median time to coeliac disease diagnosis was longer in children aged < 5 years at diabetes onset (3.3 years) compared with older children (0.7 years, P < 0.001). CONCLUSIONS: Coeliac disease is common in young people with Type 1 diabetes; the risk is greatest with diabetes onset < 5 years, but after longer diabetes duration. Screening for coeliac disease should be performed at diabetes diagnosis and for at least 10 years in young children.


Assuntos
Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Adolescente , Fatores Etários , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , New South Wales , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
12.
Comput Methods Programs Biomed ; 108(1): 176-85, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22459102

RESUMO

The scaling (fractal) characteristics of electrocardiograms (ECG) provide information complementary to traditional linear measurements (heart rate, repolarisation rate etc.) allowing them to discriminate signal changes induced pathologically or pharmacologically. Under such interventions scaling behaviour is described by multiple local scaling exponents and the signal is termed multifractal. Exercise testing is used extensively to quantify and monitor cardiorespiratory health, yet to our knowledge there has been no previous multifractal investigation of exercise-induced changes in heart rate dynamics. Ambulatory ECGs were acquired from eight healthy participants. Linear descriptive statistics and a parameterisation of multifractal singularity spectra were determined for inter-beat (RR) and intra-beat (QT) time-series before and after exercise. Multivariate analyses of both linear and multifractal measures discriminated between pre- and post-exercise periods and proportionally more significant correlations were observed between linear than between multifractal measures. Variance was more uniformly distributed over the first three principal components for multifractal measures and the two classes of measures were uncorrelated. Order and phase randomisation of the time-series indicated that both sample distribution and correlation properties contribute to multifractalilty. This exploratory study indicates the possibility of using physical exercise in conjunction with multifractal methodology as an adjunctive description of autonomically mediated modulation of heart rate.


Assuntos
Eletrocardiografia/métodos , Exercício Físico , Fractais , Adulto , Humanos , Masculino
13.
Vet Rec ; 169(2): 48, 2011 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-21709047

RESUMO

In this study, previously unreported cohort characteristics and seizure patterns for canine epilepsy were identified from a series of UK-based epileptic dogs containing 1260 cases from 79 known pedigree breeds and a group of crossbreed dogs.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/genética , Epilepsia/veterinária , Linhagem , Fatores Etários , Animais , Castração/veterinária , Estudos de Coortes , Cães , Epilepsia/epidemiologia , Epilepsia/genética , Feminino , Predisposição Genética para Doença , Masculino , Fatores Sexuais , Reino Unido/epidemiologia
14.
Vet Comp Orthop Traumatol ; 24(4): 262-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21597649

RESUMO

OBJECTIVES: To investigate the association of the major histocompatability (MHC) class II allele haplotype frequencies with the diagnosis of cranial cruciate ligament (CCL) rupture in two breeds of dog. METHODS: DNA samples from populations of Labrador Retrievers and Golden Retrievers with CCL rupture and general populations of the same breeds were characterised for three DLA class II loci (DRB1*, DQA1* and DQB1*) alleles using sequence-based typing or reference strand-mediated conformation analysis. RESULTS: Although distinct differences in haplotype types, frequencies and homozygozity were observed between the two breeds, no disease specific association could be identified for the development of the CCL rupture within either population. CLINICAL SIGNIFICANCE: The risk for developing CCL rupture was not associated with DLA haplotype group(s) in Labrador Retrievers or Golden Retrievers, thus the hypothesis that there is an autoimmune basis to CCL rupture was not supported.


Assuntos
Lesões do Ligamento Cruzado Anterior , Doenças do Cão/etiologia , Complexo Principal de Histocompatibilidade/fisiologia , Ruptura/veterinária , Animais , Estudos de Casos e Controles , Doenças do Cão/genética , Cães , Regulação da Expressão Gênica/fisiologia , Predisposição Genética para Doença , Complexo Principal de Histocompatibilidade/genética , Fatores de Risco , Ruptura/etiologia , Ruptura/genética
15.
Anim Genet ; 42(2): 181-90, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21070295

RESUMO

Domestic dogs share a wide range of important disease conditions with humans, including cancers, diabetes and epilepsy. Many of these conditions have similar or identical underlying pathologies to their human counterparts and thus dogs represent physiologically relevant natural models of human disorders. Comparative genomic approaches whereby disease genes can be identified in dog diseases and then mapped onto the human genome are now recognized as a valid method and are increasing in popularity. The majority of dog breeds have been created over the past few hundred years and, as a consequence, the dog genome is characterized by extensive linkage disequilibrium (LD), extending usually from hundreds of kilobases to several megabases within a breed, rather than tens of kilobases observed in the human genome. Genome-wide canine SNP arrays have been developed, and increasing success of using these arrays to map disease loci in dogs is emerging. No equivalent of the human HapMap currently exists for different canine breeds, and the LD structure for such breeds is far less understood than for humans. This study is a dedicated large-scale assessment of the functionalities (LD and SNP tagging performance) of canine genome-wide SNP arrays in multiple domestic dog breeds. We have used genotype data from 18 breeds as well as wolves and coyotes genotyped by the Illumina 22K canine SNP array and Affymetrix 50K canine SNP array. As expected, high tagging performance was observed with most of the breeds using both Illumina and Affymetrix arrays when multi-marker tagging was applied. In contrast, however, large differences in population structure, LD coverage and pairwise tagging performance were found between breeds, suggesting that study designs should be carefully assessed for individual breeds before undertaking genome-wide association studies (GWAS).


Assuntos
Doenças do Cão/genética , Cães/genética , Genoma/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Cruzamento , Mapeamento Cromossômico/veterinária , Feminino , Predisposição Genética para Doença , Genética Populacional , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Desequilíbrio de Ligação , Masculino , Especificidade da Espécie
17.
Scand J Med Sci Sports ; 20(6): 794-804, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20561274

RESUMO

Electrocardiographic (ECG) monitoring allows temporal analysis of cardiac rhythm. We are usually interested in the variability of two components of the ECG: RR interval (a surrogate marker of cardiac interval) and QT interval (the duration of ventricular depolarization/repolarization). Quantification of RR rhythm, called heart rate variability (HRV) analysis, reflects the cardiac influences of the autonomic nervous system. QT variability provides insight regarding the risk of ventricular arrhythmia, and is at least partially independent of HRV. In this review, we consider the analysis of ECG time series during physical exercise. Our objectives were to show the variety of methods that can be used to characterize these time series data and to demonstrate "normal" changes in these characteristics during exercise and recovery. Attaining a comprehensive understanding of cardiac electrical conduction changes during exercise is not straightforward: analysis methods are numerous and results require careful interpretation. However, we recommend that assessment of both HRV and QT properties yields the most valuable information, the utility of which can be appreciated from the viewpoints of the athlete (e.g. providing feedback on the cardiac effects of training), the clinician (assisting in cardiovascular screening and exercise therapy evaluation) and the exercise physiologist (providing data for physiological process modelling).


Assuntos
Eletrocardiografia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Coração/fisiologia , Sistema Nervoso Autônomo/fisiologia , Humanos , Síndrome do QT Longo , Fatores de Tempo
18.
Tissue Antigens ; 75(3): 242-52, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20196832

RESUMO

Canine diabetes mellitus (DM) shares many similarities with human type 1 diabetes (T1D). It is a complex genetic disorder, which shows marked differences in breed susceptibility, with Samoyed dogs being highly susceptible, whereas the Boxer breed is relatively resistant. A number of immune response genes, which have been associated with human T1D, have also been implicated in determining susceptibility to canine DM, suggesting an immune-mediated component to the disease pathogenesis. Single nucleotide polymorphisms (SNPs) in the CTLA4 gene have consistently and reproducibly been associated with human T1D and other autoimmune diseases but the canine CTLA4 gene has not previously been investigated for involvement in canine DM. SNPs of particular interest in the human association studies are those in the promoter region which affect CTLA4 expression levels, and that of exon 1 which results in a non-synonymous amino acid change. We performed a canine SNP discovery investigation of CTLA4 on a region of DNA containing exon 1 and 1.5 kb upstream sequence in order to identify promoter region SNPs. Confirmed SNPs were used in a genetic association study of a canine diabetic cohort showing that CTLA4 promoter polymorphisms were associated with diabetes in crossbreed dogs and in five Pedigree breeds-Samoyed, Miniature Schnauzer, West Highland White Terrier, Border Terrier and Labrador. Meta-analysis of these breeds showed 9 out of 15 SNPs were associated with DM and genotype and haplotype analyses also confirmed the allelic associations in these breeds.


Assuntos
Diabetes Mellitus/veterinária , Doenças do Cão/genética , Estudos de Associação Genética , Polimorfismo de Nucleotídeo Único , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Sequência de Bases , Diabetes Mellitus/genética , Diabetes Mellitus/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/imunologia , Cães , Éxons , Genótipo , Haplótipos , Humanos , Masculino , Polimorfismo Genético , Sequências Reguladoras de Ácido Nucleico
19.
Tissue Antigens ; 73(3): 218-24, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19254251

RESUMO

Anal furunculosis (AF) is a chronic inflammatory disease of perianal tissues that particularly affects German Shepherd dogs (GSD). An immune-mediated aetiopathogenesis is suggested by T-cell infiltration, upregulated cytokine gene expression, clinical response to ciclosporin therapy and a strong genetic association with the DLA-DRB1*00101 allele. Given the close proximity of TNFA and DLA-DRB1 in the canine major histocompatibility complex (MHC), together with the strong linkage disequilibrium (LD) observed across this region, the primary disease association could be with either locus. We have investigated whether there may be an association of AF with TNFA gene polymorphism in GSDs. Cohorts of AF-affected and AF-unaffected GSDs of known dog leucocyte antigen (DLA) class II profile were genotyped for 10 single nucleotide polymorphisms (SNPs) in the canine TNFA locus using Sequenom iPLEX technology. Seven discrete TNFA haplotypes were identified in GSDs for combinations of these SNPs. TNFA haplotype frequencies were compared in cases and controls. The TNFA haplotype 3 (ATCGTTACGG), was at significantly increased frequency in cases (29% vs 15%, OR 2.5, 95% CI 1.4-4.8; P = 0.003). All seven discrete TNFA SNP haplotypes were examined for their association with DLA-DRB1/DQA1/DQB1 established haplotypes. TNFA haplotype 3 was preferentially associated with both DLA-DRB1*00101(3A)- and DLA-DRB1*00102(3B)-positive haplotypes. The DLA-DRB1* 00101/TNFA-3A haplotype was significantly associated with AF (19.3% vs 5.8%; OR 3.7, 95% CI: 1.5-8.9; P = 0.003), whereas the DLA-DRB1*00102/TNFA-3B haplotype was not (P = NS). These findings suggest that susceptibility to AF in GSDs is primarily associated with DLA-DRB1*00101 and any association with the TNFA locus is secondary and is likely to be because of LD.


Assuntos
Doenças do Ânus/veterinária , Doenças do Cão/genética , Furunculose/veterinária , Antígenos HLA-DR/genética , Desequilíbrio de Ligação/genética , Fator de Necrose Tumoral alfa/genética , Animais , Doenças do Ânus/genética , Doenças do Ânus/imunologia , Doenças do Cão/imunologia , Cães , Furunculose/genética , Furunculose/imunologia , Predisposição Genética para Doença , Cadeias HLA-DRB1 , Polimorfismo de Nucleotídeo Único
20.
Mol Ecol ; 18(3): 403-14, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19161464

RESUMO

Among freshwater organisms, water flow is frequently considered to be one of the most important environmental variables affecting life-history traits such as dispersal abilities and therefore genetic structure. Recent studies have suggested that habitat type alone as defined by water flow is predictive of genetic population differentiation, while others have advocated against broad generalizations in favour of more conservative, species-specific conclusions. If aquatic habitat type is predictive of population differentiation, then one would expect sympatric taxa that occupy the same aquatic habitat to converge on a similar genetic structure. We tested this prediction by examining the haplotype diversity, phylogeographical concordance, population connectivity and population isolation of three lotic water beetle species in southern California: Anacaena signaticollis, Eubrianax edwardsii and Stictotarsus striatellus. In addition to coarse habitat and geography, we also controlled for the potentially confounding factors of range size, method of dispersal and clade independence. Together, the species spanned extremes of genetic and phylogeographical structure in all measures examined, suggesting that a coarse dichotomy of aquatic habitat type is not predictive of genetic structure. While there is little question that water flow plays a major role in shaping the life-history traits of freshwater organisms, it is perilous to confer predictive properties to an artificially simplistic dichotomy or use it as a surrogate for other unmeasured variables.


Assuntos
Besouros/genética , Ecossistema , Água Doce , Especiação Genética , Movimentos da Água , Animais , California , Besouros/classificação , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Variação Genética , Dados de Sequência Molecular , Densidade Demográfica , Valor Preditivo dos Testes , Análise de Sequência de DNA
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