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1.
J Small Anim Pract ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38736278

RESUMO

OBJECTIVES: Prospectively collected data were used to estimate the prevalence of gingivitis in a cohort of companion cats aged up to 6 years and to investigate factors associated with the risk of gingivitis in cats aged 3 to 4 years. MATERIALS AND METHODS: Data were obtained from a longitudinal study of domestic cats (the Bristol Cats Study), using owner-completed questionnaires and veterinary surgeon-completed oral health scores. Prevalence estimates of veterinary-reported gingivitis for cats aged up to 6 years old (n = 1534) were calculated for different age groups. Cat signalment, diet and dental care were assessed for association with gingivitis in cats aged 3 to 4 years (n = 317) using univariable and multiple logistic regression. RESULTS: The prevalence of gingivitis increased with age and ranged from 24.5% (<12 months old) to 56.3% (5 to 6 years old). Odds of gingivitis in cats aged 3 to 4 years were higher in cats fed a wet only or mixed wet/dry diet compared to dry only (odds ratio: 2.7; 95% confidence interval: 1.4 to 5.1), cats not reported to hunt compared to reported hunters (odds ratio: 2.1; 95% confidence interval: 1.0 to 4.2), cats reported to dribble whilst being stroked at age 6 months compared to reported non-dribblers (odds ratio: 3.2; 95% confidence interval: 1.3 to 8.4) and cats with orange variants in their coat colour compared to non-orange cats (odds ratio: 2.3; 95% confidence interval: 1.0 to 5.3). CLINICAL SIGNIFICANCE: These results will help veterinary surgeons identify cats that may be at a greater risk of gingivitis and provide an evidence base to inform dietary and oral healthcare recommendations aimed at promoting gingival health in cats.

2.
Anim Genet ; 54(4): 536-543, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36990727

RESUMO

Horns, a form of headgear carried by Bovidae, have ethical and economic implications for ruminant production species such as cattle and goats. Hornless (polled) individuals are preferred. In cattle, four genetic variants (Celtic, Friesian, Mongolian and Guarani) are associated with the polled phenotype, which are clustered in a 300-kb region on chromosome 1. As the variants are intergenic, the functional effect is unknown. The aim of this study was to determine if the POLLED variants affect chromatin structure or disrupt enhancers using publicly available data. Topologically associating domains (TADs) were analyzed using Angus- and Brahman-specific Hi-C reads from lung tissue of an Angus (Celtic allele) cross Brahman (horned) fetus. Predicted bovine enhancers and chromatin immunoprecipitation sequencing peaks for histone modifications associated with enhancers (H3K27ac and H3K4me1) were mapped to the POLLED region. TADs analyzed from Angus- and Brahman-specific Hi-C reads were the same, therefore, the Celtic variant does not appear to affect this level of chromatin structure. The Celtic variant is located in a different TAD from the Friesian, Mongolian, and Guarani variants. Predicted enhancers and histone modifications overlapped with the Guarani and Friesian variants but not the Celtic or Mongolian variants. This study provides insight into the mechanisms of the POLLED variants for disrupting horn development. These results should be validated using data produced from the horn bud region of horned and polled bovine fetuses.


Assuntos
Cornos , Bovinos/genética , Animais , Mutação , Fenótipo , Alelos , Cabras/genética , Cromatina
3.
J Dairy Sci ; 106(1): 407-420, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400619

RESUMO

Sperm motility is directly related to the ability of sperm to move through the female reproductive tract to reach the ovum. Sperm motility is a complex trait that is influenced by environmental and genetic factors and is associated with male fertility, oocyte penetration rate, and reproductive success of cattle. In this study we carried out a GWAS in Italian Holstein bulls to identify candidate regions and genes associated with variations in progressive and total motility (PM and TM, respectively). After quality control, the final data set consisted of 5,960 records from 949 bulls having semen collected in 10 artificial insemination stations and genotyped at 412,737 SNPs (call rate >95%; minor allele frequency >5%). (Co)variance components were estimated using single trait mixed models, and associations between SNPs and phenotypes were assessed using a genomic BLUP approach. Ten windows that explained the greatest percentage of genetic variance were located on Bos taurus autosomes 1, 2, 4, 6, 7, 23, and 26 for TM and Bos taurus autosomes 1, 2, 4, 6, 8, 16, 23, and 26 for PM. A total of 150 genes for TM and 72 genes for PM were identified within these genomic regions. Gene Ontology enrichment analyses identified significant Gene Ontology terms involved with energy homeostasis, membrane functions, sperm-egg interactions, protection against oxidative stress, olfactory receptors, and immune system. There was significant enrichment of quantitative trait loci for fertility, calving ease, immune response, feed intake, and carcass weight within the candidate windows. These results contribute to understanding the architecture of the genetic control of sperm motility and may aid in the development of strategies to identify subfertile bulls and improve reproductive success.


Assuntos
Sêmen , Motilidade dos Espermatozoides , Animais , Bovinos/genética , Feminino , Masculino , Genômica , Locos de Características Quantitativas , Sêmen/fisiologia , Motilidade dos Espermatozoides/genética , Espermatozoides
4.
Theriogenology ; 145: 77-85, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004821

RESUMO

Developmental competence determines the oocyte capacity to support initial embryo growth, but the molecular mechanisms underlying this phenomenon are still ill-defined. Changes in microRNA (miRNA) expression pattern have been described during follicular growth in several species. Therefore, aim of this study was to investigate whether miRNA expression pattern in cow oocyte and follicular fluid (FF) is associated with the acquisition of developmental competence. Samples were collected from ovaries with more than, or fewer than, 10 mid-antral follicles (H- and L-ovaries) because previous studies demonstrated that this parameter is a reliable predictor of oocyte competence. After miRNA deep sequencing and bioinformatic data analysis, we identified 58 miRNAs in FF and 6 in the oocyte that were differentially expressed between H- and L-ovaries. Overall, our results indicate that miRNA levels both in FF and in the ooplasm must remain within specific thresholds and that changes in either direction compromising oocyte competence. Some of the miRNAs found in FF (miR-769, miR-1343, miR-450a, miR-204, miR-1271 and miR-451) where already known to regulate follicle growth and their expression pattern indicate that they are also involved in the acquisition of developmental competence. Some miRNAs were differentially expressed in both compartments but with opposite patterns, suggesting that miRNAs do not flow freely between FF and oocyte. Gene Ontology analysis showed that the predicted gene targets of most differentially expressed miRNAs are part of a few signalling pathways. Regulation of maternal mRNA storage and mitochondrial activity seem to be the processes more functionally relevant in determining oocyte quality. In conclusion, our data identified a few miRNAs in the follicular fluid and in the ooplasm that modulate the oocyte developmental competence. This provides new insights that could help with the management of cattle reproductive efficiency.


Assuntos
Bovinos , Líquido Folicular/química , MicroRNAs/metabolismo , Oócitos/metabolismo , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética
5.
Anim Genet ; 51(2): 166-176, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31999853

RESUMO

Horns are paired appendages on the head of bovine species, comprising an inner bony core and outer keratin sheath. The horn bud forms during early fetal development but ossification of the developing horn does not occur until approximately 1 month after birth. Little is known about the genetic pathways that lead to horn growth. Hornless, or polled, animals are found in all domestic bovids. Histological studies of bovine fetuses have shown that the horn bud does not form in polled individuals. There are currently four known genetic variants for polledness in cattle on BTA1. All of the variants are intergenic, but probably affect regulation of nearby genes or long non-coding RNAs. Transcriptomic studies suggest that the expression of two nearby long non-coding RNAs are affected by the Celtic POLLED variant, but further studies are required to confirm these data. Candidate genes located elsewhere in the genome are involved in regulating bone formation and epithelial-to-mesenchymal transition. Expression of one of these candidate genes, RXFP2, appears to be reduced in the fetal horn bud of polled animals carrying the Celtic variant compared with horned individuals. Investigating horn ontogenesis and the genetic pathway by which the POLLED variants prevent horn development has implications for cattle breeding. If the genetic basis of horn bud formation and polledness is better understood, then new targets may be identified for precision genome editing to create polled individuals.


Assuntos
Bovinos/genética , Variação Genética , Cornos/crescimento & desenvolvimento , Mutação , Animais , Bovinos/crescimento & desenvolvimento , Feminino , Duplicação Gênica , Marcadores Genéticos , Masculino
6.
Animal ; 13(10): 2156-2163, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30835192

RESUMO

Mastitis is an inflammatory disease of the mammary gland, which has a significant economic impact and is an animal welfare concern. This work examined the association between single nucleotide polymorphisms (SNPs) and copy number variations (CNVs) with the incidence of clinical mastitis (CM). Using information from 16 half-sib pairs of Holstein-Friesian cows (32 animals in total) we searched for genomic regions that differed between a healthy (no incidence of CM) and a mastitis-prone (multiple incidences of CM) half-sib. Three cows with average sequence depth of coverage below 10 were excluded, which left 13 half-sib pairs available for comparisons. In total, 191 CNV regions were identified, which were deleted in a mastitis-prone cow, but present in its healthy half-sib and overlapped in at least nine half-sib pairs. These regions overlapped with exons of 46 genes, among which APP (BTA1), FOXL2 (BTA1), SSFA2 (BTA2), OTUD3 (BTA2), ADORA2A (BTA17), TXNRD2 (BTA17) and NDUFS6 (BTA20) have been reported to influence CM. Moreover, two duplicated CNV regions present in nine healthy individuals and absent in their mastitis-affected half-sibs overlapped with exons of a cholinergic receptor nicotinic α 10 subunit on BTA15 and a novel gene (ENSBTAG00000008519) on BTA27. One CNV region deleted in nine mastitis-affected sibs overlapped with two neighbouring long non-coding RNA sequences located on BTA12. Single nucleotide polymorphisms with differential genotypes between a healthy and a mastitis-affected sib included 17 polymorphisms with alternate alleles in eight affected and healthy half-sib families. Three of these SNPs were located introns of genes: MET (BTA04), RNF122 (BTA27) and WRN (BTA27). In summary, structural polymorphisms in form of CNVs, putatively play a role in susceptibility to CM. Specifically, sequence deletions have a greater effect on reducing resistance against mastitis, than sequence duplications have on increasing resistance against the disease.


Assuntos
Variações do Número de Cópias de DNA , Genoma/genética , Mastite Bovina/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Bovinos , Suscetibilidade a Doenças , Feminino , Patrimônio Genético , Genótipo , Íntrons/genética , Glândulas Mamárias Animais , Deleção de Sequência
7.
BMC Genomics ; 19(1): 410, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29843606

RESUMO

BACKGROUND: The number of studies of Copy Number Variation in cattle has increased in recent years. This has been prompted by the increased availability of data on polymorphisms and their relationship with phenotypes. In addition, livestock species are good models for some human phenotypes. In the present study, we described the landscape of CNV driven genetic variation in a large population of 146 individuals representing 13 cattle breeds, using whole genome DNA sequence. RESULTS: A highly significant variation among all individuals and within each breed was observed in the number of duplications (P < 10-15) and in the number of deletions (P < 10-15). We also observed significant differences between breeds for duplication (P = 0.01932) and deletion (P = 0.01006) counts. The same variation CNV length - inter-individual and inter-breed differences were significant for duplications (P < 10-15) and deletions (P < 10-15). Moreover, breed-specific variants were identified, with the largest proportion of breed-specific duplications (9.57%) found for Fleckvieh and breed-specific deletions found for Brown Swiss (5.00%). Such breed-specific CNVs were predominantly located in intragenic regions, however in Simmental, one deletion present in five individuals was found in the coding sequence of a novel gene ENSBTAG00000000688 on chromosome 18. In Brown Swiss, Norwegian Red and Simmental breed-specific deletions were located within KIT and MC1R genes, which are responsible for a coat colour. The functional annotation of coding regions underlying the breed-specific CNVs showed that in Norwegian Red, Guernsey, and Simmental significantly under- and overrepresented GO terms were related to chemical stimulus involved in sensory perception of smell and the KEGG pathways for olfactory transduction. In addition, specifically for the Norwegian Red breed, the dopaminergic synapse KEGG pathway was significantly enriched within deleted parts of the genome. CONCLUSIONS: The CNV landscape in Bos taurus genome revealed by this study was highly complex, with inter-breed differences, but also a significant variation within breeds. The former, may explain some of the phenotypic differences among analysed breeds, and the latter contributes to within-breed variation available for selection.


Assuntos
Bovinos/genética , Variações do Número de Cópias de DNA/genética , Animais , Especificidade da Espécie
8.
Clin Obes ; 8(1): 11-20, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29052345

RESUMO

The prevalence of overweight/obesity is disproportionately higher among racial/ethnic minority and low-income patients. The purpose of this study was to survey racially diverse, low-income patients regarding their experiences with and desires regarding their providers' involvement in weight management. Adult patients (N = 529), including mostly African American (42.7%), White (44.6%) and low-income (55.5% with incomes <$30 000) patients from 7 Patient-Centered Medical Homes voluntarily completed a brief anonymous survey while waiting to see their providers. Only 19.8% of the patients said that their primary care provider frequently or very frequently talked with them about their weight. Older patients as compared to younger patients, as well as males compared to females, were more likely to have their primary care provider talk to them about their diet and physical activity during the last year. It was also found that 56.9% of the patients were interested in getting help from their doctor to connect with resources for weight management in their community. African American patients, as compared to White patients, were more interested in getting such help. These results suggest that there is a need to establish healthcare policies and training in primary care settings that are designed to ensure that primary care providers routinely talk with all of their patients, including their female and older patients, about their weight and weight management services. Additionally, primary care administrators need to play an increased role in identifying, developing, and advocating for affordable weight management services, particularly in African American and low-income communities.


Assuntos
Atitude do Pessoal de Saúde , Negro ou Afro-Americano/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Obesidade/terapia , Pacientes/psicologia , Papel do Médico , Médicos de Atenção Primária/psicologia , Atenção Primária à Saúde , População Branca/psicologia , Adolescente , Adulto , Fatores Etários , Idoso , Comunicação , Assistência à Saúde Culturalmente Competente , Feminino , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Disparidades em Assistência à Saúde , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Obesidade/etnologia , Obesidade/fisiopatologia , Obesidade/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Assistência Centrada no Paciente , Relações Médico-Paciente , Pobreza , Comportamento de Redução do Risco , Fatores Sexuais , Programas de Redução de Peso , Adulto Jovem
9.
Neuropathol Appl Neurobiol ; 43(4): 330-345, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28039900

RESUMO

AIMS: The secondary dystroglycanopathies represent a heterogeneous group of congenital muscular dystrophies characterized by the defective glycosylation of alpha dystroglycan. These disorders are associated with mutations in at least 17 genes, including Fukutin-related protein (FKRP). At the severe end of the clinical spectrum there is substantial brain involvement, and cobblestone lissencephaly is highly suggestive of these disorders. The precise pathogenesis of this phenotype has, however, remained unclear with most attention focused on the disruption to the radial glial scaffold. Here, we set out to investigate whether lesions are apparent prior to the differentiation of the radial glia. METHODS: A detailed investigation of the structural brain defects from embryonic day 10.5 (E10.5) up until the time of birth (P0) was undertaken in the Fkrp-deficient mice (FKRPKD ). Reelin, and downstream PI3K/Akt signalling pathways were analysed using Western blot. RESULTS: We show that early basement membrane defects and neuroglial ectopia precede radial glial cell differentiation. Furthermore, we identify mislocalization of Cajal-Retzius cells which nonetheless is not associated with any apparent disruption to the reelin, and downstream PI3K/Akt signalling pathways. CONCLUSIONS: These observations identify Cajal-Retzius cell mislocalization as an early event during the development of cortical defects thereby identifying an earlier onset and more complex pathogenesis than originally reported for the secondary dystroglycanopathies. Overall this study provides new insight into central nervous system involvement in this group of diseases.


Assuntos
Encéfalo/patologia , Síndrome de Walker-Warburg/patologia , Animais , Animais Recém-Nascidos , Movimento Celular , Modelos Animais de Doenças , Embrião de Mamíferos , Camundongos , Camundongos Mutantes , Mutação de Sentido Incorreto , Pentosiltransferases , Proteínas/genética , Proteína Reelina , Transferases
10.
Animal ; 11(4): 574-579, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27534682

RESUMO

The possibility of using genetic control strategies to increase disease resistance to infectious diseases relies on the identification of markers to include in the breeding plans. Possible incomplete exposure of mastitis-free (control) animals, however, is a major issue to find relevant markers in genetic association studies for infectious diseases. Usually, designs based on elite dairy sires are used in association studies, but an epidemiological case-control strategy, based on cows repeatedly field-tested could be an alternative for disease traits. To test this hypothesis, genetic association results obtained in the present work from a cohort of Italian Holstein cows tested for mastitis over time were compared with those from a previous genome-wide scan on Italian Holstein sires genotyped with 50k single nucleotide polymorphisms for de-regressed estimated breeding values for somatic cell counts (SCCs) on Bos taurus autosome (BTA6) and BTA14. A total of 1121 cows were selected for the case-control approach (cases=550, controls=571), on a combination of herd level of SCC incidence and of within herd individual level of SCC. The association study was conducted on nine previously identified markers, six on BTA6 and four on BTA14, using the R statistical environment with the 'qtscore' function of the GenABEL package, on high/low adjusted linear score as a binomial trait. The results obtained in the cow cohort selected on epidemiological information were in agreement with those obtained from the previous sire genome-wide association study (GWAS). Six out of the nine markers showed significant association, four on BTA14 (rs109146371, rs109234250, rs109421300, rs109162116) and two on BTA6 (rs110527224 and rs42766480). Most importantly, using mastitis as a case study, the current work further validated the alternative use of historical field disease data in case-control designs for genetic analysis of infectious diseases in livestock.


Assuntos
Estudos de Associação Genética/veterinária , Mastite Bovina/genética , Animais , Estudos de Casos e Controles , Bovinos , Feminino , Estudos de Associação Genética/métodos , Itália , Polimorfismo de Nucleotídeo Único
11.
Reprod Fertil Dev ; 29(8): 1545-1555, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27623773

RESUMO

MicroRNAs (miRNAs) are known to control several reproductive functions, including oocyte maturation, implantation and early embryonic development. Recent advances in deep sequencing have allowed the analysis of all miRNAs of a sample. However, when working with embryos, due to the low RNA content, miRNA profiling is challenging because of the relatively large amount of total RNA required for library preparation protocols. In the present study we compared three different procedures for RNA extraction and prepared libraries using pools of 30 bovine blastocysts. In total, 14 of the 15 most abundantly expressed miRNAs were common to all three procedures. Furthermore, using miRDeep discovery and annotation software (Max Delbrück Center), we identified 1363 miRNA sequences, of which bta-miR-10b and bta-miR-378 were the most abundant. Most of the 179 genes identified as experimentally validated (86.6%) or predicted targets (13.4%) were associated with cancer canonical pathways. We conclude that reliable analysis of bovine blastocyst miRNAs can be achieved using the procedures described herein. The repeatability of the results across different procedures and independent replicates, as well as their consistency with results obtained in other species, support the biological relevance of these miRNAs and of the gene pathways they modulate in early embryogenesis.


Assuntos
Blastocisto/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Animais , Bovinos , Epigênese Genética , Feminino , MicroRNAs/genética , Gravidez
12.
J Anim Sci ; 95(11): 4820-4834, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29293723

RESUMO

Although vaccination is an effective measure in reducing the risk of bovine respiratory disease complex (BRDC) in cattle, BRDC losses remain significant. Increasing the efficacy of vaccination depends on elucidating the protective immune response to different antigens included in vaccines, determining the best timing for vaccination, and understanding the impact of the age of the calf on vaccination. This study measured the serum antibodies present in calves following vaccination against 4 viruses commonly associated with BRDC: bovine viral diarrhea virus type 1 and 2 (BVDV1 and BVDV2), bovine respiratory syncytial virus (BRSV), and bovine herpesvirus 1 (BHV1). Serum antibody titers were measured in more than 1,600 calves at 3-wk intervals starting at the time of the first vaccination. This first vaccination occurred at weaning for approximately half of the individuals and 3 wk before weaning for the other half. Dam age (years), time of weaning (initial vaccination or booster vaccination), and age of calf within year-season (days within year-season) classification all were found to have a significant effect on measured traits such as the initial titer and overall response. An increased initial titer was negatively correlated with each response trait (initial, booster, and overall response). Calves that were weaned at initial vaccination had greater overall antibody response to BVDV1 and BVDV2 compared with calves weaned 3 wk before initial vaccination. In contrast, calves given their initial vaccination 3 wk before weaning had greater overall antibody response to BRSV and BHV1 compared with calves that were vaccinated at weaning. Furthermore, the circulating antibody titer at which each virus needed to be below for an individual calf to positively respond to vaccination was determined (log titer of 0.38 for BVDV1, 1.5 for BVDV2, 3.88 for BRSV, and 1.5 for BHV1). This information can be used to improve vaccination protocols to allow for a greater response rate of individuals to vaccination and, hopefully, improved protection.


Assuntos
Anticorpos Antivirais/sangue , Complexo Respiratório Bovino/prevenção & controle , Herpesvirus Bovino 1/imunologia , Pestivirus/imunologia , Vírus Sincicial Respiratório Bovino/imunologia , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Formação de Anticorpos , Complexo Respiratório Bovino/imunologia , Complexo Respiratório Bovino/virologia , Bovinos , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Vírus da Diarreia Viral Bovina Tipo 2/imunologia , Feminino , Masculino , Gravidez , Vacinas Atenuadas/imunologia , Desmame
13.
Anim Genet ; 47(1): 19-27, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26559490

RESUMO

Local breeds of livestock are of conservation significance as components of global biodiversity and as reservoirs of genetic variation relevant to the future sustainability of agriculture. One such rare historic breed, the Chillingham cattle of northern England, has a 350-year history of isolation and inbreeding yet shows no diminution of viability or fertility. The Chillingham cattle have not been subjected to selective breeding. It has been suggested previously that the herd has minimal genetic variation. In this study, high-density SNP genotyping with the 777K SNP chip showed that 9.1% of loci on the chip are polymorphic in the herd, compared with 62-90% seen in commercial cattle breeds. Instead of being homogeneously distributed along the genome, these loci are clustered at specific chromosomal locations. A high proportion of the Chillingham individuals examined were heterozygous at many of these polymorphic loci, suggesting that some loci are under balancing selection. Some of these frequently heterozygous loci have been implicated as sites of recessive lethal mutations in cattle. Linkage disequilibrium equal or close to 100% was found to span up to 1350 kb, and LD was above r(2) = 0.25 up to more than 5000 kb. This strong LD is consistent with the lack of polymorphic loci in the herd. The heterozygous regions in the Chillingham cattle may be the locations of genes relevant to fitness or survival, which may help elucidate the biology of local adaptation in traditional breeds and facilitate selection for such traits in commercial cattle.


Assuntos
Bovinos/genética , Heterozigoto , Endogamia , Polimorfismo de Nucleotídeo Único , Animais , Conservação dos Recursos Naturais , Inglaterra , Feminino , Loci Gênicos , Genótipo , Técnicas de Genotipagem , Masculino
14.
J Math Biol ; 73(1): 63-90, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26454759

RESUMO

We analyse the model for vegetation growth in a semi-arid landscape proposed by von Hardenberg et al. (Phys. Rev. Lett. 87:198101, 2001), which consists of two parabolic partial differential equations that describe the evolution in space and time of the water content of the soil and the level of vegetation. This model is a generalisation of one proposed by Klausmeier but it contains additional terms that capture additional physical effects. By considering the limit in which the diffusion of water in the soil is much faster than the spread of vegetation, we reduce the system to an asymptotically simpler parabolic-elliptic system of equations that describes small amplitude instabilities of the uniform vegetated state. We carry out a thorough weakly nonlinear analysis to investigate bifurcations and pattern formation in the reduced model. We find that the pattern forming instabilities are subcritical except in a small region of parameter space. In the original model at large amplitude there are localised solutions, organised by homoclinic snaking curves. The resulting bifurcation structure is well known from other models for pattern forming systems. Taken together our results describe how the von Hardenberg model displays a sequence of (often hysteretic) transitions from a non-vegetated state, to localised patches of vegetation that exist with uniform low-level vegetation, to periodic patterns, to higher-level uniform vegetation as the precipitation parameter increases.


Assuntos
Ecossistema , Modelos Biológicos , Fenômenos Fisiológicos Vegetais , Solo/química , Dinâmica não Linear , Chuva , Água
15.
Osteoarthritis Cartilage ; 23(11): 1981-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26521744

RESUMO

OBJECTIVE: To define how the catabolic cytokines (Interleukin 1 (IL-1) and tumor necrosis factor alpha (TNFα)) affect the circadian clock mechanism and the expression of clock-controlled catabolic genes within cartilage, and to identify the downstream pathways linking the cytokines to the molecular clock within chondrocytes. METHODS: Ex vivo cartilage explants were isolated from the Cry1-luc or PER2::LUC clock reporter mice. Clock gene dynamics were monitored in real-time by bioluminescence photon counting. Gene expression changes were studied by qRT-PCR. Functional luc assays were used to study the function of the core Clock/BMAL1 complex in SW-1353 cells. NFкB pathway inhibitor and fluorescence live-imaging of cartilage were performed to study the underlying mechanisms. RESULTS: Exposure to IL-1ß severely disrupted circadian gene expression rhythms in cartilage. This effect was reversed by an anti-inflammatory drug dexamethasone, but not by other clock synchronizing agents. Circadian disruption mediated by IL-1ß was accompanied by disregulated expression of endogenous clock genes and clock-controlled catabolic pathways. Mechanistically, NFкB signalling was involved in the effect of IL-1ß on the cartilage clock in part through functional interference with the core Clock/BMAL1 complex. In contrast, TNFα had little impact on the circadian rhythm and clock gene expression in cartilage. CONCLUSION: In our experimental system (young healthy mouse cartilage), we demonstrate that IL-1ß (but not TNFα) abolishes circadian rhythms in Cry1-luc and PER2::LUC gene expression. These data implicate disruption of the chondrocyte clock as a novel aspect of the catabolic responses of cartilage to pro-inflammatory cytokines, and provide an additional mechanism for how chronic joint inflammation may contribute to osteoarthritis (OA).


Assuntos
Condrócitos/metabolismo , Relógios Circadianos/genética , Citocinas/genética , DNA/genética , Regulação da Expressão Gênica , NF-kappa B/genética , Osteoartrite/genética , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Células Cultivadas , Citocinas/biossíntese , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , NF-kappa B/biossíntese , Osteoartrite/metabolismo , Osteoartrite/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Eur J Cancer Care (Engl) ; 23(3): 363-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24127815

RESUMO

This study identifies the incidence of hyponatraemia in cancer patients on an inpatient rehabilitation unit and examines the association between admission hyponatraemia and rehabilitation length of stay (LOS), functional outcome, and survival. After institutional review committee's approval, we retrospectively reviewed medical records of 295 consecutive patients who were admitted to this inpatient cancer rehabilitation unit between 27 January 2009 through 31 July 2010 in a tertiary cancer centre. The incidence of hyponatraemia in cancer patients admitted to our inpatient rehabilitation unit was 41.4%. Median rehabilitation LOS for patients with mild (Na 130-134 mEq/L) and moderate-severe (Na < 130 mEq/L) hyponatraemia was 11 and 15 days, respectively, which was significantly longer than patients with eunatraemia (10 days; P = 0.03). Functional Independence Measure gain for ambulation and transfers during inpatient rehabilitation stay was not significantly different between three different patient groups. We concluded that large portion of patients who require acute inpatient rehabilitation presented with hyponatraemia, which is associated with prolonged rehabilitation LOS. Whether aggressive management of hyponatraemia will shorten rehabilitation stay needs further study.


Assuntos
Institutos de Câncer , Hiponatremia/epidemiologia , Tempo de Internação/estatística & dados numéricos , Neoplasias/reabilitação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Unidades Hospitalares , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
17.
Bull Hosp Jt Dis (2013) ; 72(4): 284-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25986353

RESUMO

Magnetic resonance imaging (MRI) scans are widely used in the assessment of knees, often prior to arthroscopic procedures. The reporting of osteochondral damage on MRI scans can be variable. The correlation between MRI reports of osteochondral damage and that found at arthroscopy is often inconsistent. A retrospective case-note review of a single-surgeon series of 175 arthroscopic procedures was performed. Eighty-three patients were included in the study. The remainder were excluded if an MRI scan had not been performed or had been performed more than 3-months before surgery. The condition of the articular cartilage demonstrated by MRI was compared to that found at arthroscopy. Data was analysed for presence and extent of osteochondral damage. Comparison between MRI and arthroscopy findings showed high specificity (90%) and negative predictive values (89%) for osteochondral damage but low sensitivity (46%). Cohen's kappa values < 0.2 revealed very poor correlation for the extent of damage. This study demonstrates MRI as a good identifier of osteochondral damage but an unreliable descriptor for such change.


Assuntos
Artroscopia/métodos , Cartilagem Articular/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
18.
Anim Genet ; 44(5): 493-501, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23611291

RESUMO

Consumers demand healthy and palatable meat, both factors being affected by fat composition. However, red meat has relatively high concentration of saturated fatty acids and low concentration of the beneficial polyunsaturated fatty acids. To select animals prone to produce particular fat types, it is necessary to identify the genes influencing muscle lipid composition. This paper describes an association study in which a large panel of candidate genes involved in adipogenesis, lipid metabolism and energy homoeostasis was tested for effects on fat composition in 15 European cattle breeds. Sixteen genes were found to have significant effects on different lipid traits, and among these, CFL1 and MYOZ1 were found to have large effects on the ratio of 18:2/18:3, CRI1 on the amount of neutral adrenic acid (22:4 n-6), MMP1 on docosahexaenoic acid (22:6 n-3) and conjugated linoleic acid, PLTP on the ratio of n-6:n-3 and IGF2R on flavour. Several genes - ALDH2, CHRNE, CRHR2, DGAT1, IGFBP3, NEB, SOCS2, SUSP1, TCF12 and FOXO1 - also were found to be associated with both lipid and organoleptic traits although with smaller effect. The results presented here help in understanding the genetic and biochemical background underlying variations in fatty acid composition and flavour in beef.


Assuntos
Bovinos/genética , Bovinos/metabolismo , Carne/análise , Músculo Esquelético/química , Adipogenia , Animais , Haplótipos , Metabolismo dos Lipídeos , Masculino , Redes e Vias Metabólicas , Músculo Esquelético/metabolismo , Polimorfismo de Nucleotídeo Único
19.
J Anim Sci ; 90(9): 3213-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22966080

RESUMO

Long distance transportation of weaned piglets (Sus scrofa) is increasingly common in the united states and may result in delayed eating, drinking, or normal social behaviors. A potential solution is a mid-journey rest (lairage). The objective of this study was to determine if a lairage altered behavior after a 16-h transport. Pigs that weighed approximately 18 kg each (n = 894) were housed in 16 pens with 8 pens per treatment. Lairaged pigs were transported for 8 h and given an 8-h rest with food and water, whereas control pigs were transported continuously for 16 h. The heaviest, the lightest, and 2 average-BW pigs relative to the average weight of the pen were observed by video recording for 24 h immediately before and after transport, and during d 6 and 13 after transport. Postures (lying, sitting, and standing) were recorded using 10-min-interval scan sampling, and behavioral categories included inactivity, activities (eating, drinking, alert, manipulating pen, rooting, and walking) and social interactions (aggression, belly nosing, playing, tail biting, and positive social behaviors). In both treatments, sitting occurred most before transport (P < 0.01) than at other times, but did not differ between treatments. Standing increased (time effect; P < 0.01) for both treatments immediately after transport through d 6, but returned to pre-transport values by d 13. In contrast, lying decreased (time effect; P < 0.01) after transport, but returned to above pre-transport values by d 13. Time effects were evident for activity (P < 0.01), pen manipulation (P = 0.05), rooting (P < 0.01), initiation of belly-nosing (P = 0.01), and receiving belly-nosing (P = 0.03); however, initiation of aggression did not differ for day (P = 0.19) or treatment (P = 0.56). Lairaged pigs initiated more (P = 0.05) play than continuously transported pigs, but no differences (P = 0.84) were seen in receipt of play behavior. Pigs that were to be transported for 16 h continuously walked less pre-transport, walked more post-transport (treatment × time interaction; P = 0.02), and drank less pre-transport, but drank more on all days post-transport compared with the lairage group (treatment × time interaction; P = 0.001). This study indicated that extended transport without lairage alters some swine behaviors relevant to production (water consumption) and demonstrated that a long-duration transport, regardless of the mid-journey lairage treatment, affects a number of behaviors up to 13 d after transportation.


Assuntos
Comportamento Animal/fisiologia , Descanso/fisiologia , Suínos/fisiologia , Meios de Transporte , Criação de Animais Domésticos , Bem-Estar do Animal , Animais , Peso Corporal , Jogos e Brinquedos , Fatores de Tempo , Caminhada
20.
J Anim Sci ; 90(7): 2152-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22767550

RESUMO

The objectives of this study were to determine if sires perform consistently across altitude and to quantify the genetic relationship between growth and survival at differing altitudes. Data from the American Angus Association included weaning weight (WW) adjusted to 205 (n = 77,771) and yearling weight adjusted to 365 (n = 39,450) d of age from 77,771 purebred Angus cattle born in Colorado between 1972 and 2007. Postweaning gain (PWG) was calculated by subtracting adjusted WW from adjusted yearling weight. Altitude was assigned to each record based upon the zip code of each herd in the database. Records for WW and PWG were each split into 2 traits measured at low and high altitude, with the records from medium altitude removed from the data due to inconsistencies between growth performance and apparent culling rate. A binary trait, survival (SV), was defined to account for censored records at yearling for each altitude. It was assumed that, at high altitude, individuals missing a yearling weight either died or required relocation to a lower altitude predominantly due to brisket disease, a condition common at high altitude. Model 1 considered each WW and PWG measured at 2 altitudes as separate traits. Model 2 treated PWG and SV measured as separate traits due to altitude. Models included the effects of weaning contemporary group, age of dam, animal additive genetic effects, and residual. Maternal genetic and maternal permanent environmental effects were included for WW. Heritability estimates for WW in Model 1 were 0.28 and 0.26 and for PWG were 0.26 and 0.19 with greater values in low altitude. Genetic correlations between growth traits measured at different altitude were moderate in magnitude: 0.74 for WW and 0.76 for PWG and indicate possibility of reranking of sires across altitude. Maternal genetic correlation between WW at varying altitude of 0.75 also indicates these may be different traits. In Model 2, heritabilities were 0.14 and 0.27 for PWG and 0.36 and 0.47 for SV. Genetic correlation between PWG measured at low and high altitude was 0.68. Favorable genetic correlations were estimated between SV and PWG within and between altitudes, suggesting that calves with genetics for increased growth from weaning to yearling also have increased genetic potential for SV. Genetic evaluations of PWG in different altitudes should consider preselection of the data, by using a censoring trait, like survivability to yearling.


Assuntos
Altitude , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Genótipo , Criação de Animais Domésticos , Animais , Estados Unidos
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