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1.
J Dairy Sci ; 100(8): 6602-6619, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28601460

RESUMO

Production from pasture-based dairy farms can be increased through using N fertilizer to increase pasture grown, increasing stocking rate, importing feeds from off farm (i.e., supplementary feeds, such as cereal silages, grains, or co-product feeds), or through a combination of these strategies. Increased production can improve profitability, provided the marginal cost of the additional milk produced is less than the milk price received. A multiyear production system experiment was established to investigate the biological and economic responses to intensification on pasture-based dairy farms; 7 experimental farmlets were established and managed independently for 3 yr. Paddocks and cows were randomly allocated to farmlet, such that 3 farmlets had stocking rates of 3.35 cows/ha (LSR) and 4 farmlets had stocking rates of 4.41 cows/ha (HSR). Of the LSR farmlets, 1 treatment received no N fertilizer, whereas the other 2 received either 200 or 400 kg of N/ha per year (200N and 400N, respectively). No feed was imported from off-farm for the LSR farmlets. Of the 4 HSR farmlets, 3 treatments received 200N and the fourth treatment received 400N; cows on 2 of the HSR-200N farmlet treatments also received 1.3 or 1.1 t of DM/cow per year of either cracked corn grain or corn silage, respectively. Data were analyzed for consistency of farmlet response over years using mixed models, with year and farmlet as fixed effects and the interaction of farmlet with year as a random effect. The biological data and financial data extracted from a national economic database were used to model the statement of financial performance for the farmlets and determine the economic implications of increasing milk production/cow and per ha (i.e., farm intensification). Applying 200N or 400N increased pasture grown per hectare and milk production per cow and per hectare, whereas increasing stocking rate did not affect pasture grown or milk production per hectare, but reduced milk production per cow. Importing feed in the HSR farmlets increased milk production per cow and per hectare. Marginal milk production responses to additional feed (i.e., either pasture or imported supplementary feed) were between 0.8 and 1.2 kg of milk/kg of DM offered (73 to 97 g of fat and protein/kg of feed DM) and marginal response differences between feeds were explained by metabolizable energy content differences (0.08 kg of milk/MJ of metabolizable energy offered). The marginal milk production response to additional feed was quadratic, with the greatest milk production generated from the initial investment in feed; 119, 99, and 55 g of fat and protein were produced per kilogram of feed DM by reducing the annual feed deficit from 1.6 to 1.0, 1.0 to 0.5, and 0.5 to 0 t of DM, respectively. Economic modeling indicated that the marginal cost of milk produced from pasture resulting from applied N fertilizer was less than the milk price; therefore, strategic use of N fertilizer to increase pasture grown increased farm operating profit per hectare. In comparison, operating profit declined with purchased feed, despite high marginal milk production responses. The results have implications for the strategic direction of grazing dairy farms, particularly in export-oriented industries, where the prices of milk and feed inputs are subject to the considerable volatility of commodity markets.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Indústria de Laticínios/métodos , Lactação/fisiologia , Animais , Feminino , Leite , Poaceae , Estações do Ano , Silagem
2.
Mol Psychiatry ; 18(6): 721-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22889924

RESUMO

Tourette's syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association study (GWAS) of TS in 1285 cases and 4964 ancestry-matched controls of European ancestry, including two European-derived population isolates, Ashkenazi Jews from North America and Israel and French Canadians from Quebec, Canada. In a primary meta-analysis of GWAS data from these European ancestry samples, no markers achieved a genome-wide threshold of significance (P<5 × 10(-8)); the top signal was found in rs7868992 on chromosome 9q32 within COL27A1 (P=1.85 × 10(-6)). A secondary analysis including an additional 211 cases and 285 controls from two closely related Latin American population isolates from the Central Valley of Costa Rica and Antioquia, Colombia also identified rs7868992 as the top signal (P=3.6 × 10(-7) for the combined sample of 1496 cases and 5249 controls following imputation with 1000 Genomes data). This study lays the groundwork for the eventual identification of common TS susceptibility variants in larger cohorts and helps to provide a more complete understanding of the full genetic architecture of this disorder.


Assuntos
Colágenos Fibrilares/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Síndrome de Tourette/genética , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 9/genética , Feminino , Genótipo , Humanos , Cooperação Internacional , Masculino , Metanálise como Assunto , Transtorno Obsessivo-Compulsivo/etiologia , Transtorno Obsessivo-Compulsivo/genética , Síndrome de Tourette/complicações , População Branca/genética , Adulto Jovem
3.
Nat Genet ; 13(2): 154-60, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8640220

RESUMO

In a study of human diversity at a highly variable locus, we have mapped the internal structures of tandem-repetitive alleles from different populations at the minisatellite MS205 (D16S309). The results give an unusually detailed view of the different allelic structures represented on modern human chromosomes, and of the ancestral relationships between them. There was a clear difference in allelic diversity between African and non-African populations. A restricted set of allele families was found in non-African populations, and formed a subset of the much greater diversity seen on African chromosomes. The data strongly support a recent African origin for modern human diversity at this locus.


Assuntos
Evolução Biológica , DNA Satélite/genética , Variação Genética , Hominidae/genética , África , Alelos , Animais , Sequência de Bases , Europa (Continente) , Frequência do Gene , Humanos , Modelos Genéticos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos
4.
Nat Genet ; 26(3): 358-61, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11062480

RESUMO

Binary polymorphisms associated with the non-recombining region of the human Y chromosome (NRY) preserve the paternal genetic legacy of our species that has persisted to the present, permitting inference of human evolution, population affinity and demographic history. We used denaturing high-performance liquid chromatography (DHPLC; ref. 2) to identify 160 of the 166 bi-allelic and 1 tri-allelic site that formed a parsimonious genealogy of 116 haplotypes, several of which display distinct population affinities based on the analysis of 1062 globally representative individuals. A minority of contemporary East Africans and Khoisan represent the descendants of the most ancestral patrilineages of anatomically modern humans that left Africa between 35,000 and 89,000 years ago.


Assuntos
Etnicidade/genética , Evolução Molecular , Hominidae/genética , Filogenia , Cromossomo Y/genética , África , Animais , Cromatografia Líquida de Alta Pressão , Haplótipos/genética , Humanos , Masculino , Modelos Genéticos , Dados de Sequência Molecular , Desnaturação de Ácido Nucleico , Análise de Sequência de DNA , Especificidade da Espécie
5.
Eye (Lond) ; 37(12): 2554-2558, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36627444

RESUMO

BACKGROUND: The process of becoming visually impaired or blind is undoubtedly a highly emotional experience, requiring practical and psychological support. Information on mental health support provision in the UK across the sight-loss pathway, however, is largely unknown, especially amongst healthcare practitioners that are often sought after for advice: the referring optometrist and eye clinic liaison officer (ECLO). This study aims to ascertain the perceived accessibility and quality of mental health support across the sight-loss pathway. METHODS: Semi-structured individual interviews were conducted with patients with a diagnosed eye condition who had received care from a hospital eye service, referring optometrists, and ECLOs. Following interview transcription, results were synthesised in a narrative analysis. RESULTS: A total of 28 participants were included in the analysis, of which 17 were participants with various eye conditions, five were referring optometrists, and five were ECLOs. After analysis, three broad themes emerged: (1) The emotional trauma of diagnosis (2) Availability of mental health support; (3) The point where mental health support is most needed across the sight-loss pathway. Several patients reporting that they had received no offer of support nor were they signposted to any possible sources. Referring optometrists and ECLO's agreed. CONCLUSION: It is important that referring optometrists are aware of the need for mental health support services and can signpost to local support services including the third sector anytime during the referral process. Future large-scale, UK-wide research into referral practice and signposting for mental health support for patients is warranted, to identify how services can be improved in order to ensure that the wellbeing of patients is maintained.


Assuntos
Oftalmopatias , Optometristas , Optometria , Humanos , Saúde Mental , Cegueira , Oftalmopatias/diagnóstico , Oftalmopatias/terapia , Atenção à Saúde
6.
Health Soc Care Community ; 30(6): e4020-e4027, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35302269

RESUMO

Racism is a key modifiable determinant of health that contributes to health inequities in Aotearoa and elsewhere. Experiences of racism occur within the health sector for workers, patients and their whanau (extended family) every day. This paper uses stories of racism from nurses - reworked into vignettes - to examine the dynamics of racism to generate possible micro, meso and macro anti-racism interventions. A critical qualitative design was utilised, informed by kaupapa Maori approaches. The five vignettes in this paper were sourced from a pair of caucused focus groups with nine senior Maori (Indigenous peoples of Aotearoa) and Tauiwi (non-Maori) nurses held in Auckland Aotearoa in 2019. The vignettes were lightly edited and then critically analysed by both authors to identify sites of racism and generate ideas for anti-racism interventions. The vignettes illustrate five key themes in relation to racism. These include (i) mono-cultural practice, (ii) everyday micro-aggressions; (iii) complexity and the costs of racism, (iv) Pakeha (white settler) privilege and (v) employment discrimination. From analysing these themes, a range of evidence-based micro, meso and macro-level anti-racism interventions were derived. These ranged from engaging in reflective practice, education initiatives, monitoring, through to collective advocacy. Vignettes are a novel way to reveal sites of racism to create teachable moments and spark reflective practice and more active engagement in anti-racism interventions. When systematically analysed vignettes can be utilised to inform and refine anti-racist interventions. Being able to identify racism is essential to being able to effectively counter racism.


Assuntos
Antirracismo , Racismo , Humanos , Havaiano Nativo ou Outro Ilhéu do Pacífico , Etnicidade , Grupos Focais , Nova Zelândia
7.
Mol Psychiatry ; 15(2): 216-25, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18574484

RESUMO

Genetic variation at the catechol-O-methyltransferase (COMT) gene has been significantly associated with risk for various neuropsychiatric conditions such as schizophrenia, panic disorder, bipolar disorders, anorexia nervosa and others. It has also been associated with nicotine dependence, sensitivity to pain and cognitive dysfunctions especially in schizophrenia. The non-synonymous single nucleotide polymorphism (SNP) in exon 4--Val108/158Met--is the most studied SNP at COMT and is the basis for most associations. It is not, however, the only variation in the gene; several haplotypes exist across the gene. Some studies indicate that the haplotypic combinations of alleles at the Val108/158Met SNP with those in the promoter region and in the 3'-untranslated region are responsible for the associations with disorders and not the non-synonymous SNP by itself. We have now studied DNA samples from 45 populations for 63 SNPs in a region of 172 kb across the region of 22q11.2 encompassing the COMT gene. We focused on 28 SNPs spanning the COMT-coding region and immediately flanking DNA, and found that the haplotypes are from diverse evolutionary lineages that could harbor as yet undetected variants with functional consequences. Future association studies should be based on SNPs that define the common haplotypes in the population(s) being studied.


Assuntos
Catecol O-Metiltransferase/genética , Predisposição Genética para Doença , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único/genética , Grupos Populacionais/genética , Animais , Bases de Dados Genéticas , Frequência do Gene , Genótipo , Humanos
8.
J Exp Med ; 123(1): 55-74, 1966 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-5902571

RESUMO

Lymphoma 6C3HED-OG cells, known from previous work to be susceptible to the effects of guinea pig serum in vivo and dependent upon extrinsic asparagine for protein synthesis and growth in vitro, remained for the most part morphologically intact and countable in the electronic cell counter following exposures of 1 and 2 hr to the effects of heated (56 degrees C, 30 min) guinea pig serum injected into the peritoneal cavities of mice in which the lymphoma cells were growing rapidly; after exposures of 4 and 6 hr the bulk of the -OG cells remained still intact and countable in the cell counter, though by this time a small proportion of them (5 to 12%) proved stainable with eosin in wet preparations) hence were presumably nonviable. After 12, 16, and 24 hr of exposure, however, the bulk of the -OG cells were either lysed or fragmented, to the extent that they did not register in the cell counter. Morphologic studies of the cells exposed 16 and 24 hr to the effects of heated guinea pig serum in vivo, disclosed that most of the cells then remaining were either frankly necrotic or greatly altered otherwise, marked vacuolation of the cytoplasm being the most conspicuous alteration in cells not yet obviously necrotic. Long before the bulk of the Lymphoma 6C3HED-OG cells had become conspicuously changed morphologically following exposure to the effects of heated guinea pig serum in vivo, they manifested striking alterations in protein metabolism, as was disclosed by "pulse" studies with radioactive valine. For example, the protein metabolism of -OG cells, as measured by their incorporation of L-valine-C(14), was sharply curtailed following 15 min of exposure to heated guinea pig serum in vivo, as compared with valine incorporation by cells labeled immediately after exposure to the guinea pig serum. Following exposure to heated guinea pig serum during 60 min, -OG cells incorporated less than half as much L-valine-C(14) as did cells labeled immediately after exposure, and the incorporation of L-valine-C(14) was still less after 120 min of exposure. By contrast, Lymphoma -RG1 cells, known from previous work to be wholly insusceptible to the effects of guinea pig serum in vivo and independent of need for extrinsic asparagine for protein synthesis and growth in vitro, showed no curtailment whatever of protein synthesis following exposures to the effects of heated guinea pig serum in vivo during periods of 15, 60, and 120 min. Reasons are given for considering the prompt inhibition of protein synthesis in the asparagine-dependent -OG cells a direct result of asparagine-deprivation induced in vivo by the injected guinea pig serum, the L-asparaginase of which presumably converted the available L-asparagine of the host to L-aspartic acid that was not taken up by the -OG cells. The synthesis of deoxyribonucleic acid by Lymphoma 6C3HED-OG cells, as measured by the incorporation of thymidme-H(3), determined with the aid of liquid scintillation counting and autoradiography, was also altered by exposure of the lymphoma cells to the effects of heated guinea pig serum in vivo, though not during exposures of 15 and 60 min; only after an exposure of 120 min did the population of -OG cells incorporate notably less thymidine-H(3) than did control populations, though after 240 min of exposure the -OG cells incorporated less than one-fifth as much tritiated thymidineas had -OG cells exposed to heated guinea pig serum for 60 min or to heated horse serum for periods up to 240 min. Autoradiographs indicated that DNA synthesis by -OG cells normally proceeds at an intense level that leads to some 60% of these cells being heavily labeled in autoradiographs at any given time; after exposure to the effects of heated guinea pig serum during 2 and 4 hr in vivo, however, the lymphoma cells lost their ability to incorporate enough tritiated thymidine to become heavily labeled, but approximately the same proportion of them (56 to 58%) retained their ability to incorporate sufficient tritiated thymidine to become lightly labeled. The possibility is considered that the inhibition of DNA synthesis in the asparagine-dependent -OG cells exposed to the effects of heated guinea pig serum in vivo may be secondary to the previously manifest inhibition of protein synthesis. Further, in tests of ribonucleic acid metabolism of Lymphoma 6C3HED-OG cells after exposure to the effects of heated guinea pig serum in vivo during periods of 15, 60, 120, and 240 min, the findings indicated that the ability of the lymphoma cells to synthesize RNA, as measured by their capacity to incorporate uridine-5-H(3), remained unaltered during the exposures of 15, 60, and 120 min, but was substantially reduced following 240 min of exposure. The findings are considered in relation to the probability, disclosed in part by previous studies, that heated guinea pig serum brings about its effects upon Lymphoma 6C3HED-OG cells in vivo by providing active L-asparaginase in large amounts, which presumably converts the available (extracellular) asparagine of the host to aspartic acid, the latter not being taken up by the lymphoma cells in vivo or in vitro. Hence it seems likely that heated guinea pig serum in this way brings about a state of asparagine deprivation that is responsible for the sequential metabolic and morphologic alterations that become manifest in asparagine-dependent Lymphoma 6C3HED-OG cells following their exposure to the effects of guinea pig serum in vivo, as here described.


Assuntos
DNA de Neoplasias/biossíntese , Linfoma/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Neoplásico/biossíntese , Animais , Sangue , Isótopos de Carbono , Cobaias , Camundongos , Timidina , Imunologia de Transplantes , Trítio , Uridina , Valina/metabolismo
9.
Pediatr Blood Cancer ; 54(2): 332-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19852066

RESUMO

Certain beta globin gene mutations produce a thalassemia major phenotype in the heterozygous state. While most such patients have thalassemia intermedia, we describe a young Guatemalan child with a de novo mutation in the beta globin gene, codon 31 T --> G (Hemoglobin Hakkari), who developed severe anemia at the age of 10 months and remains transfusion-dependent. The substitution of B13 leucine with arginine in the beta globin results in alteration of a critical heme contact point resulting in an extremely unstable variant hemoglobin and a clinical picture that is characterized by ineffective erythropoiesis and numerous intracytoplasmic inclusions within the erythrocyte precursors of the bone marrow. .


Assuntos
Hemoglobinas Anormais/genética , Mutação Puntual , Globinas beta/genética , Talassemia beta/genética , Guatemala , Humanos , Corpos de Inclusão , Lactente , Masculino , Talassemia beta/patologia
10.
Child Care Health Dev ; 36(5): 678-85, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20337640

RESUMO

BACKGROUND: This study aimed to investigate child and carers' attitudes towards child involvement in paediatric consultations. METHODS: Semi-structured qualitative interviews explored child and carers' attitudes towards child involvement at different stages of the paediatric consultation process. Twenty families (21 children, 17 mothers and 5 fathers) were interviewed following a paediatric (index) consultation in two UK paediatric inpatient and outpatient departments. RESULTS: All but one family felt the child should be involved at some stage of the consultation process but the desired extent and nature of involvement depended on child, family and illness characteristics, as well as on the stages of the consultation. During history gathering, some parents and children felt it was the decision and responsibility of the parent to facilitate communication between the child and the doctor. Others expected the doctor to decide when and how to facilitate this process. At diagnosis the desired amount of information given to the child increased with increasing maturity in the child. Some felt making a diagnosis should be a collaborative process; others felt it was solely the domain of the doctor. In discussing and making a treatment plan, some children wanted to be given the choice of being involved and some wanted their parents to be responsible for implementing the plan. Some families with a seriously ill child, however, wanted the burden of involvement in the management plan taken away from them. CONCLUSIONS: Families vary in their views about involvement of children in paediatric consultations in a way that may be unique to each child, family and illness. Moreover, different views were expressed about involvement in each stage of the consultative process and in management of the child's health. The challenge for doctors is to determine the level of involvement and information exchange favoured by a particular parent and child. Good practice recommendations emerging from the analysis are described.


Assuntos
Cuidadores/psicologia , Participação do Paciente/psicologia , Pediatria/normas , Adolescente , Criança , Comunicação , Feminino , Humanos , Masculino , Participação do Paciente/métodos , Satisfação do Paciente , Relações Médico-Paciente , Pesquisa Qualitativa
11.
Science ; 260(5105): 210-4, 1993 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-8469974

RESUMO

Mackerels, tunas, and billfishes (suborder Scombroidei and Teleostei) provide an ideal taxonomic context in which to examine the evolution of endothermy. Multiple origins and diverse strategies for endothermy exist among these fish. Here a molecular phylogeny of the Scombroidei has been determined by direct sequencing of a portion of the mitochondrial cytochrome b gene. The distribution of endothermic species within this proposed genealogy indicates that the ability to warm the brain and retina arose independently in three lineages, each time in association with a movement into colder water. This suggests that the evolution of cranial endothermy in fish was selected in order to permit thermal niche expansion and not selected for increased aerobic capacity.


Assuntos
Evolução Biológica , Regulação da Temperatura Corporal , Peixes/fisiologia , Atum/fisiologia , Animais , Sequência de Bases , Encéfalo/fisiologia , Grupo dos Citocromos b/genética , Peixes/classificação , Peixes/genética , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Músculos/fisiologia , Filogenia , Retina/fisiologia , Atum/classificação , Atum/genética
12.
Science ; 271(5254): 1380-7, 1996 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-8596909

RESUMO

Haplotypes consisting of alleles at a short tandem repeat polymorphism (STRP) and an Alu deletion polymorphism at the CD4 locus on chromosome 12 were analyzed in more than 1600 individuals sampled from 42 geographically dispersed populations (13 African, 2 Middle Eastern, 7 European, 9 Asian, 3 Pacific, and 8 Amerindian). Sub-Saharan African populations had more haplotypes and exhibited more variability in frequencies of haplotypes than the Northeast African or non-African populations. The Alu deletion was nearly always associated with a single STRP allele in non-African and Northeast African populations but was associated with a wide range of STRP alleles in the sub-Saharan African populations. This global pattern of haplotype variation and linkage disequilibrium suggests a common and recent African origin for all non-African human populations.


Assuntos
Antígenos CD4/genética , Cromossomos Humanos Par 12 , Evolução Molecular , Hominidae/genética , Desequilíbrio de Ligação , Polimorfismo Genético , África , Alelos , Animais , Sequência de Bases , Frequência do Gene , Variação Genética , Haplótipos , Humanos , Dados de Sequência Molecular , Primatas/genética , Sequências Repetitivas de Ácido Nucleico , Deleção de Sequência
13.
J Dairy Sci ; 92(5): 1954-62, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19389952

RESUMO

Increasing levels of dairy cow mortality pose a challenge to the US dairy industry. The industry's current understanding of dairy cow mortality is reliant upon descriptions largely based on producer or veterinary assumptions regarding cause of death without the benefit of detailed postmortem evaluations. A thorough necropsy is a superior tool for establishing a cause of death, except for cases involving euthanasia for traumatic accidents or severe locomotor disorders. Information provided from a necropsy examination would be most valuable if it were categorized and combined with cow health information in a complete postmortem evaluation designed to guide future management decisions. The objective of this study was to describe dairy cow deaths on a Colorado dairy over a 1-yr period and explore classification systems for necropsy findings that might inform management actions aimed at reducing dairy cow mortality. Throughout the study period a thorough necropsy examination was performed on every cow that died. Based upon this examination each death was characterized by a proximate cause (i.e., the most likely immediate cause of the death). Each proximate cause of death was then categorized using 3 alternate schemes founded on generalized etiologic principles and influenced by previous clinical history and treatments. These schemes included the broad categories commonly used for classifying findings within a review of literature related to dairy cow mortality, a diagnostic scheme used within the problem-oriented veterinary medical record, and an analysis focusing on the primary physiologic system derangement for each death. A total of 2,067 cows were enrolled during the study period of which 1,468 cows freshened, 507 cows were sold, and 94 cows died, resulting in a mortality risk of 6.4 deaths per 100 lactations at risk. The distribution of deaths by parity was significantly different from the herd distribution at the end of study with the largest percentage of death present in parity > or =4. Postmortem findings attributable to a specific cause of death were present for all but 4 of the 94 deaths. Assignment of the proximate causes of death to categories within the 3 alternate schemes provided a means for classifying necropsy findings and causes of death with different levels of detail. Creating categories with more selective groupings may provide a means for capturing specifics related to deaths that can be used to guide management decisions.


Assuntos
Doenças dos Bovinos/mortalidade , Animais , Bovinos , Doenças dos Bovinos/classificação , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Causas de Morte , Distribuição de Qui-Quadrado , Colorado/epidemiologia , Indústria de Laticínios , Diagnóstico , Feminino , Fatores de Risco , Estações do Ano , Análise de Sobrevida
14.
Science ; 366(6470)2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31806784

RESUMO

Active asteroids are those that show evidence of ongoing mass loss. We report repeated instances of particle ejection from the surface of (101955) Bennu, demonstrating that it is an active asteroid. The ejection events were imaged by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft. For the three largest observed events, we estimated the ejected particle velocities and sizes, event times, source regions, and energies. We also determined the trajectories and photometric properties of several gravitationally bound particles that orbited temporarily in the Bennu environment. We consider multiple hypotheses for the mechanisms that lead to particle ejection for the largest events, including rotational disruption, electrostatic lofting, ice sublimation, phyllosilicate dehydration, meteoroid impacts, thermal stress fracturing, and secondary impacts.

15.
Cytogenet Genome Res ; 123(1-4): 234-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19287160

RESUMO

Recent large-scale genomic studies within human populations have identified numerous genomic regions as copy number variant (CNV). As these CNV regions often overlap coding regions of the genome, large lists of potentially copy number polymorphic genes have been produced that are candidates for disease association. Most of the current data regarding normal genic variation, however, has been generated using BAC or SNP microarrays, which lack precision especially with respect to exons. To address this, we assessed 2,790 candidate CNV genes defined from available studies in nine well-characterized HapMap individuals by designing a customized oligonucleotide microarray targeted specifically to exons. Using exon array comparative genomic hybridization (aCGH), we detected 255 (9%) of the candidates as true CNVs including 134 with evidence of variation over the entire gene. Individuals differed in copy number from the control by an average of 100 gene loci. Both partial- and whole-gene CNVs were strongly associated with segmental duplications (55 and 71%, respectively) as well as regions of positive selection. We confirmed 37% of the whole-gene CNVs using the fosmid end sequence pair (ESP) structural variation map for these same individuals. If we modify the end sequence pair mapping strategy to include low-sequence identity ESPs (98-99.5%) and ESPs with an everted orientation, we can capture 82% of the missed genes leading to more complete ascertainment of structural variation within duplicated genes. Our results indicate that segmental duplications are the source of the majority of full-length copy number polymorphic genes, most of the variant genes are organized as tandem duplications, and a significant fraction of these genes will represent paralogs with levels of sequence diversity beyond thresholds of allelic variation. In addition, these data provide a targeted set of CNV genes enriched for regions likely to be associated with human phenotypic differences due to copy number changes and present a source of copy number responsive oligonucleotide probes for future association studies.


Assuntos
Dosagem de Genes/genética , Polimorfismo Genético/genética , Algoritmos , Hibridização Genômica Comparativa , Éxons/genética , Reações Falso-Negativas , Reações Falso-Positivas , Humanos
16.
Pharmacogenomics J ; 8(5): 349-56, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18663376

RESUMO

Cytochrome P450 2E1, gene symbol CYP2E1, is one of a family of enzymes with a central role in activating and detoxifying xenobiotics and endogenous compounds. Genetic variation at this gene has been reported in different human populations, and some association studies have reported increased risk for cancers and other diseases. To the best of our knowledge, multi-single-nucleotide polymorphism haplotypes and linkage disequilibrium (LD) have not been systematically studied for CYP2E1 in multiple populations. Haplotypes can greatly increase the power both to identify patterns of genetic variation relevant for gene expression as well as to detect disease-related susceptibility mutations. We present frequency and LD data and analyses for 11 polymorphisms and their haplotypes that we have studied on over 2600 individuals from 50 human population samples representing the major geographical regions of the world. The diverse patterns of haplotype variation found in the different populations we have studied show that ethnicity may be an important variable helping to explain inconsistencies that have been reported by association studies. More studies clearly are needed of the variants we have studied, especially those in the 5' region, such as the variable number of tandem repeats, as well as studies of additional polymorphisms known for this gene to establish evidence relating any systematic differences in gene expression that exist to the haplotypes at this gene.


Assuntos
Alelos , Citocromo P-450 CYP2E1/genética , Haplótipos , Desequilíbrio de Ligação , Evolução Biológica , Deriva Genética , Humanos
17.
Clin Oncol (R Coll Radiol) ; 19(1): 56-62, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17305255

RESUMO

AIMS: To present further findings from the Scottish Cord Compression Study, in which the diagnosis, management and outcome of 319 patients with a definitive diagnosis of malignant cord compression (MCC) were examined. MATERIALS AND METHODS: In total, 256 (80%) patients in the study consented to be interviewed shortly after diagnosis and at follow-up interviews. One hundred and twenty-eight patients were interviewed 1 month after diagnosis (40% of the total; 57% [128/224] of patients alive 1 month after diagnosis; 68% [128/188] of patients who also consented to follow-up). Survival data of the whole MCC population and data from interviewing 128 patients 1 month after diagnosis are presented. RESULTS: The median survival of all patients was 59 days (95% confidence interval [CI] 43-75 days). The median Karnofsky performance status was 50 (interquartile range 40-60), indicating a need for considerable nursing and medical care, and was poorest for patients with lung cancer (median 40; interquartile range 30-60). The place of care was dependent on mobility at diagnosis; patients walking at diagnosis were more likely to be at home, whereas patient requiring assistance or who were unable to walk were more likely to be in institutional care (P = 0.019). Mobility and bladder function were determined by mobility and bladder function at diagnosis (P < 0.001). Of those unable to walk at diagnosis, 7% regained full mobility. Of those catheterised at presentation, 28% regained full bladder function. Forty-seven per cent (56/120, 95% CI 40-54) of patients interviewed were in pain despite oncological treatment and 18% (22/ 120; 95% CI 8-19) reported the pain as severe (visual analogue scale > 7). The median quality-of-life (Schedule for Evaluation of Individualised Quality of Life) score was 72/100, and was higher in patients with a better performance status (P = 0.026). A minority of patients (8%) screened positive for anxiety and depression using the Hospital Anxiety and Depression scale. CONCLUSIONS: Notwithstanding the difficulties in following up this group of patients, this paper reports valuable findings detailing the experience of patients with MCC 1 month after diagnosis and treatment.


Assuntos
Atividades Cotidianas , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Compressão da Medula Espinal , Neoplasias da Coluna Vertebral/complicações , Adaptação Psicológica , Idoso , Feminino , Seguimentos , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Cuidados Paliativos/psicologia , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/mortalidade , Compressão da Medula Espinal/psicologia , Compressão da Medula Espinal/terapia , Neoplasias da Coluna Vertebral/secundário , Análise de Sobrevida , Cateterismo Urinário , Caminhada
18.
Vet Rec ; 161(10): 329-34, 2007 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-17827471

RESUMO

Thirty-nine samples of synovial fluid were collected from the joints of 32 horses with suspected septic arthritis and 39 samples were collected from horses euthanased for non-orthopaedic conditions. The white blood cell counts (WBCC) were determined and the pro and active forms of matrix metalloproteinases (MMPs) 2 and 9 were measured by gelatin zymography and image analysis in each sample. The initial measurements of the ratio of proMMP9:proMMp2 and WBCC were good prognostic indicators of the survival of the horses. There was no significant relationship between the interval between the injury and the horse being referred for treatment and either the WBCC or the levels of MMP2 and MMP9 initially, and no evidence that this interval significantly affected the chances of the horses surviving.


Assuntos
Artrite Infecciosa/veterinária , Doenças dos Cavalos/enzimologia , Contagem de Leucócitos/veterinária , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Animais , Artrite Infecciosa/sangue , Artrite Infecciosa/enzimologia , Biomarcadores/análise , Estudos de Casos e Controles , Doenças dos Cavalos/sangue , Cavalos , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida , Líquido Sinovial/enzimologia
19.
Nucleic Acids Res ; 29(1): 317-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11125124

RESUMO

ALFRED (the ALelle FREquency Database) is designed to store and disseminate frequencies of alleles at human polymorphic sites for multiple populations, primarily for the population genetics and molecular anthropology communities. Currently ALFRED has information on over 180 polymorphic sites for more than 70 populations. Since our initial release of the database we have focussed on increasing the quantity and quality of data, making reciprocal links between ALFRED and other related databases, and providing useful tools to make the data more comprehensible to the end user. ALFRED is accessible from the Kidd Lab home page (http://info.med.yale. edu/genetics/kkidd/) or from ALFRED directly (http://alfred.med.yale. edu/alfred/index.asp).


Assuntos
Alelos , Bases de Dados Factuais , Frequência do Gene/genética , Variação Genética , Humanos , Serviços de Informação , Internet , Polimorfismo Genético
20.
Nucleic Acids Res ; 31(1): 270-1, 2003 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-12519999

RESUMO

Elaboration of ALFRED (http://alfred.med.yale.edu) is being continued in two directions. One of which is developing tools for efficiently annotating the entries and checking the integrity of the data already in the database while the other is to increase the quantity and accessibility of data. Information contained in ALFRED such as, polymorphic sites, number of populations and frequency tables (one sample typed for one site) has significantly increased.


Assuntos
Alelos , Bases de Dados de Ácidos Nucleicos , Frequência do Gene , Gráficos por Computador , Genética Populacional , Humanos , Polimorfismo Genético , Software
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