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3.
Trop Anim Health Prod ; 53(1): 18, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33216226

RESUMO

Milkability is an important functional trait, which is directly related to milking costs and udder health. There are no milkability traits incorporated in the South African dairy cattle breeding objectives and genetic parameter estimates for these traits are not available in this population. The main objective of the study was, therefore, to estimate the genetic parameters for milkability traits and its correlation with somatic cell scores in South African Holstein cattle. Data consisted of production and milkability records of 2719 Holstein cows, from ten herds, collected from 2016 to 2018. Genetic parameters were estimated by a multi-trait animal model using the restricted maximum likelihood (REML) procedure. Means for milking time (MT), average milk flow (AMF), maximum milk flow (MMF), and somatic cell score (SCS) were 5.20 min, 1.91 kg/min, 2.99 kg/min, and 2.06, respectively. The heritability estimates were low to moderate from 0.19 ± 0.07, 0.24 ± 0.06, 0.36 ± 0.11, and 0.41 ± 0.12, respectively, for SCS, AMF, MT, and MMF. The genetic correlations were significant (P < 0.05) among the three milkability traits ranged from - 0.31 ± 0.05 between AMF and MT to 0.85 ± 0.02 between AMF and MMF. Positive genetic correlations were observed between AMF and MMF, while the correlations for MT with the remaining milkability traits were negative. Genetic correlations of SCS with AMF, MMF, and MT were - 0.13 ± 0.04, 0.13 ± 0.04, and - 0.25 ± 0.12, respectively. The mean estimated breeding value (EBV) was estimated using cattle birth dates, and there was an increase in AMF of 0.0001 kg/min EBV per year on cattle born during the period 2002 to 2014. Maximum milk flow also showed an increasing genetic trend of 0.0003 kg/min per year over the same period. On the other hand, the genetic trend for MT was undesirable, as it increased by 0.0003 kg/min per year. The moderate to high heritability estimates for milkability traits showed that selection for improvement was possible in South African Holstein cattle. High genetic correlation between AMF and MMF implied that these two may be regarded as the same trait. Milking time can contribute towards improving the accuracy of estimating EBVs for SCS in a multi-trait analysis, and vice versa, due to the moderate correlation between the two traits. The marginal genetic trend in milkability traits may be an interrelated response to selection of other traits already under selection in the population such as SCS. Results of the current study provided a basis for including milkability traits of South African Holstein cattle in the breeding objectives.


Assuntos
Bovinos/genética , Lactação/genética , Leite/metabolismo , Animais , Cruzamento , Contagem de Células/veterinária , Feminino , Fenótipo , África do Sul
4.
BMC Musculoskelet Disord ; 21(1): 213, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264949

RESUMO

BACKGROUND: The aim of this study was to explore the feasibility of using a non-absorbable biocompatible polyester patch to augment open repair of massive rotator cuff tears (Patch group) and compare outcomes with other treatment options (Non-patch group). METHODS: Participants referred to orthopaedic clinics for rotator cuff surgery were recruited. Choice of intervention (Patch or Non-patch) was based on patient preference and intra-operative findings. Oxford Shoulder Score (OSS), Shoulder Pain and Disability Index (SPADI), and Constant score were completed at baseline and 6 months. Shoulder MRI was performed at baseline and 6 months to assess fat fraction and Goutallier classification pre- and post- treatment. Feasibility outcomes (including retention, consent and missing data) were assessed. RESULTS: Sixty-eight participants (29 in the Patch group, 39 in Non-patch group) were included (mean age 65.3 years). Conversion to consent (92.6%), missing data (0% at baseline), and attrition rate (16%) were deemed successful feasibility endpoints. There was significant improvement in the Patch group compared to Non-patch at 6 months in OSS (difference in medians 9.76 (95% CI 2.25, 17.29) and SPADI: 22.97 (95% CI 3.02, 42.92), with no substantive differences in Constant score. The patch group had a higher proportion of participants improving greater than MCID for OSS (78% vs 62%) and SPADI (63% vs 50%) respectively. Analysis of the 48 paired MRIs demonstrated a slight increase in the fat fraction for supraspinatus (53 to 55%), and infraspinatus (26 to 29%) at 6 months. These differences were similar and in the same direction when the participants were analysed by treatment group. The Goutallier score remained the same or worsened one grade in both groups equally. CONCLUSIONS: This study indicates that a definitive clinical trial investigating the use of a non-absorbable patch to augment repair of massive rotator cuff tears is feasible. In such patients, the patch has the potential to improve shoulder symptoms at 6 months. TRIAL REGISTRATION: ISRCTN, ISRCTN79844053, Registered 15th October 2014 (retrospectively registered).


Assuntos
Artroscopia/instrumentação , Materiais Biocompatíveis , Lesões do Manguito Rotador/cirurgia , Manguito Rotador/diagnóstico por imagem , Idoso , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Poliésteres , Manguito Rotador/fisiologia , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/diagnóstico por imagem , Articulação do Ombro/fisiologia , Dor de Ombro/cirurgia , Resultado do Tratamento
5.
Exp Appl Acarol ; 80(4): 569-590, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32185559

RESUMO

Host resistance to ticks can be explored as a possible approach of combating tick infestations to complement the existing unsustainable tick control methods. Thirty-six beef cattle animals were used, consisting of Angus, Brahman and Nguni breeds, with each breed contributing 12 animals. Half of the animals per breed were artificially challenged with Rhipicephalus microplus and the other half with R. decoloratus unfed larvae per animal. Skin biopsies and blood samples were collected pre-infestation and 12 h post-infestation from the feeding sites of visibly engorging ticks. The success rate of the ticks was high and had an influence even at the early time point. Increased lymphocytes and blood urea nitrogen levels as well as decreased levels of segmented neutrophils were observed in the Angus, which were the opposite of those in the Brahman and Nguni. The increase in cholesterol, which was highest in the Angus and lowest in the Nguni, may be due to altered protein metabolism. The expression profiles of genes TRAF6, TBP, LUM and B2M were significantly different among breeds. Five genes (CCR1, TLR5, TRAF6, TBP, BDA20) had increased or constant expression post-infestation, whereas the expression of CXCL8, IL-10 and TNF-α decreased or remained the same after tick challenge. Genes that showed variation are involved in discouraging long-term supply of blood meal to the tick and those associated with immune responses. The gene LUM is a potential biomarker for tick resistance in cattle. The response to infestation by the breeds was consistent across the tick species.


Assuntos
Doenças dos Bovinos/parasitologia , Resistência à Doença , Rhipicephalus , Infestações por Carrapato/veterinária , Animais , Nitrogênio da Ureia Sanguínea , Bovinos , Citocinas/genética , Linfócitos , Neutrófilos , Pele , Infestações por Carrapato/genética , Infestações por Carrapato/imunologia , Transcriptoma
6.
Clin Radiol ; 75(2): 116-122, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31582172

RESUMO

AIM: To investigate hip magnetic resonance imaging (MRI) findings in asymptomatic professional male rugby players and male ballet dancers compared to age-matched controls. MATERIALS AND METHODS: After ethics committee approval and consent from participants, 11 professional rugby players, 10 professional ballet dancers, and 10 controls completed activity and symptom questionnaires and underwent 3 T MRI of their self-declared dominant hip. Each scan was independently scored by two musculoskeletal radiologists for multiple features, including: joint morphology, acetabular labrum appearance, cartilage loss, and capsular thickness. Clinical and MRI features were assessed for variance by group using one-way analysis of variance (ANOVA) tests and Tukey post-hoc pairwise comparison of means. RESULTS: Labral tear prevalence was 87% with no significant difference between groups (p>0.05). Rates of paralabral cysts were significantly higher in ballet dancers (50%), compared to rugby players (0%) and controls (10%; p=0.01). Acetabular cartilage loss was present in 54% with no significant differences between groups. Superior capsular thickness was significantly greater in ballet dancers (5.3 mm) compared to rugby players (3.8 mm) and controls (3.8 mm; p=0.03). CONCLUSION: Despite the difference in type of activity between groups, there were equally high rates of labral tears and acetabular cartilage loss, questioning the role that sport plays in the development of these findings and their relationship to symptoms. The focally increased superior capsular thickness in ballet dancers may be an adaptive response to extreme ranges of movement.


Assuntos
Atletas , Dança , Futebol Americano , Articulação do Quadril/diagnóstico por imagem , Adulto , Doenças Assintomáticas , Estudos de Casos e Controles , Dança/lesões , Futebol Americano/lesões , Lesões do Quadril/diagnóstico por imagem , Lesões do Quadril/patologia , Articulação do Quadril/anatomia & histologia , Articulação do Quadril/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
7.
Bone Joint J ; 100-B(8): 1010-1017, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30062952

RESUMO

Aims: This study aimed to evaluate implant survival of reverse hybrid total hip arthroplasty (THA) at medium-term follow-up. Patients and Methods: A consecutive series of 1082 THAs in 982 patients with mean follow-up of 7.9 years (5 to 11.3) is presented. Mean age was 69.2 years (21 to 94). Of these, 194 (17.9%) were in patients under 60 years, 663 (61.3%) in female patients and 348 (32.2%) performed by a trainee. Head size was 28 mm in 953 hips (88.1%) or 32 mm in 129 hips (11.9%). Survival analysis was performed and subgroups compared using log rank tests. Results: Ten-year survival (122 hips at risk) was 97.2% (95% confidence interval (CI) 95.77 to 98.11) for all-cause revision. There was no difference in survival by age (p = 0.50), gender (p = 0.78), head size (p = 0.63) or surgeon grade (p = 0.36). No acetabular components underwent revision for aseptic loosening in the entire series. Four (0.4%) aseptic stem failures occurred early at a mean of 2.5 years (0.6 to 4.8) and were associated with age under 60 years (p = 0.015). There was no difference in survival by gender (p = 0.12), head size (p = 0.43) or surgeon grade (p = 0.77) for stem revision. Conclusion: This is the largest reported study into reverse hybrid THA and it confirms successful outcomes, irrespective of age, gender, head size and surgeon grade. Cite this article: Bone Joint J 2018;100-B:1010-17.


Assuntos
Artroplastia de Quadril/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Luxação do Quadril/etiologia , Prótese de Quadril/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Desenho de Prótese , Falha de Prótese/etiologia , Infecções Relacionadas à Prótese/etiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
8.
Osteoarthritis Cartilage ; 26(10): 1333-1337, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30017726

RESUMO

OBJECTIVE: Bone shape and bone marrow lesions (BMLs) represent different features of Magnetic resonance imaging (MRI)-detected subchondral pathology in osteoarthritis (OA). The aim of this study was to determine how these features are related and how they change in OA progression. METHODS: 600 participants from the Osteoarthritis Initiative (OAI) FNIH Biomarkers Initiative were included, having Kellgren-Lawrence grade 1-3, at baseline and MRI data at baseline and 24 months. The associations between 3D quantitative bone shape vectors and presence of (MRI Osteoarthritis Knee Score) MOAKS semi-quantitative BMLs (total BML size ≥1) were analysed for femurs and tibias using linear regression. Responsiveness over 24 months was calculated for both features in four pre-defined progression groups and reported as standardised response means (SRMs). Multilevel models investigated the longitudinal relationship between change in BML size and change in bone shape. RESULTS: Mean age was 61.5, 59% female and mean body mass index (BMI) 30.7. Correlation between baseline femur vector and BML was r = 0.28, P < 0.001. The presence of BMLs was associated with higher bone shape vector; coefficient (95% CI) 0.75 (0.54, 0.96) and 0.57 (0.38, 0.77) for femur and tibia respectively, both P < 0.001. After covariate adjustment, only the femur remained significant [coefficient 0.49, (95% CI 0.30, 0.68)]. Longitudinally bone vector demonstrated more responsiveness to change than BMLs (SRM 0.89 vs 0.13) while multilevel models revealed that increase in BML size was related to a more positive bone shape vector (representing worsening OA). CONCLUSION: There is a relationship between bone shape and BMLs, with prevalence of BMLs associated with increasing OA bone shape. Bone shape demonstrated greater responsiveness than semi-quantitative BMLs.


Assuntos
Medula Óssea/patologia , Fêmur/patologia , Imageamento Tridimensional , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico , Tíbia/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
9.
Clin Radiol ; 73(5): 505.e9-505.e15, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29273226

RESUMO

AIM: To assess intra-bursal corticosteroid injections (ICSI) efficacy and duration of action in the management of greater trochanteric pain syndrome (GTPS). The secondary aim was to identify patient and ultrasound (US) features predictive of treatment response. MATERIALS AND METHODS: Consecutive prospectively recruited patients undergoing US-guided ICSI therapy for GTPS received baseline pre-injection questionnaires assessing pain at rest and activity, demographics and comorbidities. Baseline US and radiography findings were reported prospectively. Follow-up was performed at 6 weeks and 6 and 12 months, and change in pain scores assessed using the Wilcoxon signed rank test. Logistic regression examined associations between demographics, US findings, and a clinically significant reduction in pain score (≥50%). RESULTS: Over 6 months, 127 patients were recruited with a median age of 63.5 years and 90% were female. The greatest pain reduction was between baseline and 6 weeks at activity (median 8 versus 5, p<0.001). The majority of patients noted a reduction in pain score, but the percentage of patients receiving a ≥50% reduction at 6 weeks, 6 months, and 12 months for pain at rest was 41%, 37%, and 36%, respectively. Regression models suggested only gluteus medius bursitis was weakly associated with pain reduction. CONCLUSION: ICSIs confer a benefit in pain reduction to a large proportion of patients in the short term, but this may not be reduced by a clinically significant amount. This small effect size and lack of predictive imaging features suggests initial management including subsequent steroid injection could be provided without imaging guidance in the majority of cases.


Assuntos
Corticosteroides/administração & dosagem , Artralgia/tratamento farmacológico , Bursite/tratamento farmacológico , Articulação do Quadril/diagnóstico por imagem , Manejo da Dor/métodos , Ultrassonografia de Intervenção , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , Síndrome , Resultado do Tratamento
10.
Osteoarthritis Cartilage ; 26(1): 62-71, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29054695

RESUMO

OBJECTIVES: Meniscal pathology is integral to knee osteoarthritis (OA) and its progression; it provides a progression biomarker and a potential treatment target. Magnetic resonance imaging (MRI) demonstrates large heterogeneity in meniscal damage; this structural complexity means measurement is difficult. The aim of this study was to apply novel 3D image analysis to determine which meniscal pathologies demonstrated most change during OA progression. METHODS: Knee images were selected from the progression cohort of the Osteoarthritis Initiative choosing participants with risk factors for medial OA progression. Medial and lateral menisci were manually segmented then analysed using a statistical shape model of the tibia as a reference surface. Responsiveness was assessed at 1 year using standardised response means (SRMs) for four constructs: meniscal volume, extrusion volume, thickness and tibial coverage; anatomical sub-regions of these constructs were also explored. RESULTS: Paired images from 86 participants (median age 61.5, 49% female, 56% obese) were included. Reliability of the novel meniscal measurements was very good intraclass correlation coefficients (ICCs all > 0.98). Meniscal volume and extrusion demonstrated no significant change. Moderate responsiveness was observed for medial meniscus thickness (SRM -0.35) and medial tibial coverage (SRM -0.36). No substantial change was seen for the lateral meniscus measures. Sub-region analysis did not improve responsiveness; while greater change was seen in the posterior medial compartment, it was associated with increased variance of the change. CONCLUSIONS: The location of meniscal damage was consistently in the posterior medial region, and two measurements (thickness and tibial coverage) were most responsive. Meniscal measures should add to discriminatory power in OA progression assessment.


Assuntos
Meniscos Tibiais/patologia , Osteoartrite do Joelho/patologia , Idoso , Índice de Massa Corporal , Doenças das Cartilagens/patologia , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores Sexuais
11.
Eur Radiol ; 28(3): 963-971, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28986631

RESUMO

OBJECTIVE: To compare the diagnostic accuracy of conventional 3T MRI against 1.5T MR arthrography (MRA) in patients with clinical femoroacetabular impingement (FAI). METHODS: Sixty-eight consecutive patients with clinical FAI underwent both 1.5T MRA and 3T MRI. Imaging was prospectively analysed by two musculoskeletal radiologists, blinded to patient outcomes and scored for internal derangement including labral and cartilage abnormality. Interobserver variation was assessed by kappa analysis. Thirty-nine patients subsequently underwent hip arthroscopy and surgical results and radiology findings were analysed. RESULTS: Both readers had higher sensitivities for detecting labral tears with 3T MRI compared to 1.5T MRA (not statistically significant p=0.07). For acetabular cartilage defect both readers had higher statistically significant sensitivities using 3T MRI compared to 1.5T MRA (p=0.02). Both readers had a slightly higher sensitivity for detecting delamination with 1.5T MRA compared to 3T MRI, but these differences were not statistically significant (p=0.66). Interobserver agreement was substantial to perfect agreement for all parameters except the identification of delamination (3T MRI showed moderate agreement and 1.5T MRA substantial agreement). CONCLUSION: Conventional 3T MRI may be at least equivalent to 1.5T MRA in detecting acetabular labrum and possibly superior to 1.5T MRA in detecting cartilage defects in patients with suspected FAI. KEY POINTS: • Conventional 3T MRI is equivalent to 1.5T MRA for diagnosing labral tears. • Conventional 3T MRI is superior to 1.5T MRA for diagnosing acetabular cartilage defect. • Conventional 3T MRI is equivalent to 1.5T MRA for diagnosing cartilage delamination. • Symptom severity score was significantly higher (p<0.05) in group proceeding to surgery.


Assuntos
Artrografia/métodos , Doenças das Cartilagens/patologia , Cartilagem Articular/diagnóstico por imagem , Impacto Femoroacetabular/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Acetábulo/diagnóstico por imagem , Adulto , Doenças das Cartilagens/complicações , Feminino , Impacto Femoroacetabular/etiologia , Humanos , Masculino , Reprodutibilidade dos Testes
12.
Bone Joint J ; 98-B(2): 201-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26850425

RESUMO

AIMS: Increasing demand for total hip and knee arthroplasty (THA/TKA) and associated follow-up has placed huge demands on orthopaedic services. Feasible follow-up mechanisms are therefore essential. METHODS: We conducted an audit of clinical follow-up decision-making for THA/TKA based on questionnaire/radiograph review compared with local practice of Arthroplasty Care Practitioner (ACP)-led outpatient follow-up. In all 599 patients attending an ACP-led THA/TKA follow-up clinic had a pelvic/knee radiograph, completed a pain/function questionnaire and were reviewed by an ACP. An experienced orthopaedic surgeon reviewed the same radiographs and questionnaires, without patient contact or knowledge of the ACP's decision. Each pathway classified patients into: urgent review, annual monitoring, routine follow-up or discharge. RESULTS: In total, 401 hip and 198 knee patients were included. There was substantial agreement between the ACP and surgeon for both hip (kappa = 0.69, 95% confidence interval (CI) 0.62 to 0.76) and knee (kappa = 0.81, 95% CI 0.74 to 0.88). Positive agreement was very high for discharge and routine follow-up; however the ACP was more likely to select annual monitoring and the surgeon urgent review. DISCUSSION: Review of the questionnaire/radiograph together identified all patients in need of increased surveillance, with good agreement for on-going patient management. However, review of the radiograph or questionnaire alone missed some patients with potential problems. A radiograph in conjunction with a questionnaire as a review may represent a cost effective THA/TKA follow-up mechanism. TAKE HOME MESSAGE: A questionnaire and radiograph-based remote review may represent a cost-effective total joint arthroplasty follow-up mechanism; thereby reducing the considerable burden that follow-up currently places on the NHS.


Assuntos
Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Idoso , Assistência Ambulatorial , Tomada de Decisão Clínica , Seguimentos , Articulação do Quadril/diagnóstico por imagem , Humanos , Articulação do Joelho/diagnóstico por imagem , Auditoria Médica , Variações Dependentes do Observador , Radiografia , Consulta Remota/métodos , Reoperação , Inquéritos e Questionários
13.
Osteoarthritis Cartilage ; 22(10): 1703-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25278079

RESUMO

BACKGROUND: Radiographic measures of osteoarthritis (OA) are based upon two dimensional projection images. Active appearance modelling (AAM) of knee magnetic resonance imaging (MRI) enables accurate, 3D quantification of joint structures in large cohorts. This cross-sectional study explored the relationship between clinical characteristics, radiographic measures of OA and 3D bone area (tAB). METHODS: Clinical data and baseline paired radiographic and MRI data, from the medial compartment of one knee of 2588 participants were obtained from the NIH Osteoarthritis Initiative (OAI). The medial femur (MF) and tibia (MT) tAB were calculated using AAM. 'OA-attributable' tAB (OA-tAB) was calculated using data from regression models of tAB of knees without OA. Associations between OA-tAB and radiographic measures of OA were investigated using linear regression. RESULTS: In univariable analyses, height, weight, and age in female knees without OA explained 43.1%, 32.1% and 0.1% of the MF tAB variance individually and 54.4% when included simultaneously in a multivariable model. Joint space width (JSW), osteophytes and sclerosis explained just 5.3%, 14.9% and 10.1% of the variance of MF OA-tAB individually and 17.4% when combined. Kellgren Lawrence (KL) grade explained approximately 20% of MF OA-tAB individually. Similar results were seen for MT OA-tAB. CONCLUSION: Height explained the majority of variance in tAB, confirming an allometric relationship between body and joint size. Radiographic measures of OA, derived from a single radiographic projection, accounted for only a small amount of variation in 3D knee OA-tAB. The additional structural information provided by 3D bone area may explain the lack of a substantive relationship with these radiographic OA measures.


Assuntos
Fêmur/patologia , Osteoartrite do Joelho/patologia , Tíbia/patologia , Fatores Etários , Idoso , Estatura , Peso Corporal , Feminino , Fêmur/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Obesidade/complicações , Tamanho do Órgão , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/diagnóstico por imagem , Osteófito/diagnóstico por imagem , Osteófito/etiologia , Osteófito/patologia , Radiografia , Tíbia/diagnóstico por imagem
14.
J Anim Breed Genet ; 131(4): 279-93, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24476043

RESUMO

Variance components for production traits were estimated using different models to evaluate maternal effects. Data analysed were records from the South African pig performance testing scheme on 22 224 pigs from 18 herds, tested between 1990 and 2008. The traits analysed were backfat thickness (BFAT), test period weight gain (TPG), lifetime weight gain (LTG), test period feed conversion ratio (FCR) and age at slaughter (AGES). Data analyses were performed by REML procedures in ASREML, where random effects were successively fitted into animal and sire models to produce different models. The first animal model had one random effect, the direct genetic effects, while the additional random effects were maternal genetic and maternal permanent environmental effects. In the sire model, the random effects fitted were sire and maternal grand sire effects. The best model considered the covariance between direct and maternal genetic effects or between sire and maternal grand sire effects. Fitting maternal genetic effects into the animal model reduced total additive variance, while the total additive variance increased when maternal grand sire effects were fitted into the sire model. The correlations between direct and maternal genetic effects were all negative, indicating antagonism between these effects, hence the need to consider both effects in selection programmes. Direct genetic correlations were higher than other correlations, except for maternal genetic correlations of FCR with TPG, LTG and AGES. There has been direct genetic improvement and almost constant maternal ability in production traits as shown by trends for estimated (EBVs) and maternal breeding values (MBVs), while phenotypic trends were similar to those for EBVs. These results suggest that maternal genetic effects should be included in selection programmes for these production traits. Therefore, the animal-maternal model may be the most appropriate model to use when estimating genetic parameters for production traits in this population.


Assuntos
Cruzamento/métodos , Padrões de Herança/genética , Carne/normas , Modelos Biológicos , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/genética , Tecido Adiposo/crescimento & desenvolvimento , Análise de Variância , Ração Animal/análise , Animais , Composição Corporal/genética , Composição Corporal/fisiologia , Peso Corporal , Feminino , África do Sul
15.
J Electrocardiol ; 47(2): 228-35, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24360343

RESUMO

BACKGROUND AND PURPOSE: Measurement of QT intervals during atrial flutter (AFL) is relevant to monitor the safety of drug delivery. Our aim is to compare QT and QTc intervals in AFL patients before and after catheter ablation in order to validate QT measurement during AFL. METHODS: 25 patients suffering from AFL underwent catheter ablation; 9 were in sinus rhythm and 16 were in AFL at the time of the procedure. Holter ECGs were continuously recorded before, during and after the procedure. In AFL signals, flutter waves were subtracted using a previously-validated deconvolution-based method. Fridericia's QTc was computed before and after ablation after hysteresis reduction. RESULTS: Comparing QTc values obtained before and after ablation showed that (1) the intervention did not significantly affect QTc, and (2) the QTc during AFL was concordant with the QTc value in sinus rhythm. CONCLUSION: QTc can be reliably measured in patients with AFL using flutter wave subtraction and hysteresis reduction.


Assuntos
Flutter Atrial/fisiopatologia , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/fisiopatologia , Idoso , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Técnica de Subtração
16.
Physiol Meas ; 30(12): 1303-25, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19843981

RESUMO

This paper describes an unsupervised signal processing method applied to three-channel unipolar electrograms recorded from human atria. These were obtained by epicardial wires sutured on the right and left atria after coronary artery bypass surgery. Atrial (A) and ventricular (V) activations had to be detected and identified on each channel, and gathered across the channels when belonging to the same global event. The algorithm was developed and optimized on a training set of 19 recordings of 5 min. It was assessed on twenty-seven 2 h recordings taken just before the onset of a prolonged atrial fibrillation for a total of 1593697 activations that were validated and classified as normal atrial or ventricular activations (A, V) and premature atrial or ventricular activations (PAA, PVA). 99.93% of the activations were detected, and amongst these, 99.89% of the A and 99.75% of the V activations were correctly labelled. In the subset of the 39705 PAA, 99.83% were detected and 99.3% were correctly classified as A. The false positive rate was 0.37%. In conclusion, a reliable fully automatic detection and classification algorithm was developed that can detect and discriminate A and V activations from atrial recordings. It can provide the time series needed to develop a monitoring system aiming to identify dynamic predictors of forthcoming cardiac events such as postoperative atrial fibrillation.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Função Atrial/fisiologia , Automação/métodos , Eletrocardiografia/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Função do Átrio Esquerdo/fisiologia , Função do Átrio Direito/fisiologia , Ponte de Artéria Coronária/métodos , Eletrodos Implantados , Reações Falso-Positivas , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo , Função Ventricular/fisiologia
17.
Animal ; 3(4): 494-500, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22444372

RESUMO

A multi-trait animal model was used to estimate genetic parameters among lactation somatic cell score (SCS) and udder-type traits in South African Jersey cattle, through restricted maximum likelihood (REML) procedures. Data comprised records on 18 321 Jersey cows in 470 herds, collected through the National Milk Recording Scheme from 1996 to 2002. Average SCS in the first three lactations (SCS1, SCS2 and SCS3) were considered as different traits and the udder-type traits were fore udder attachment (FUA), rear udder height (RUH), rear udder width (RUW), udder cleft (UC), udder depth (UD), fore teat placement (FTP), rear teat placement (RTP) and fore teat length (FTL). Heritability estimates for the respective lactation SCS were 0.07 ± 0.01, 0.11 ± 0.01 and 0.11 ± 0.02. Udder-type traits had heritability estimates ranging from 0.14 ± 0.01 for UD to 0.30 ± 0.02 for FTL. Genetic correlations between SCS and udder-type traits ranged from -0.003 ± 0.07 between FUA and SCS3 to -0.50 ± 0.07 between UD and SCS3. Slow genetic progress is expected when selection is applied independently on SCS and udder-type traits, due to the generally low heritabilities. Tightly attached shallow udders with narrowly placed rear teats are associated with low SCS in the Jersey population.

18.
Chemosphere ; 65(4): 651-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16545426

RESUMO

To observe the tolerance limit of lead phytotoxicity in cabbage (Brassica oleracea L.) var. Golden Aker plants were grown in refined sand with complete nutrient solution for 41 days. On 42nd day, pots with plants were separated into six lots. One lot was allowed to grow as such and was treated as control, in rest of the five lots, lead was applied at 0.1, 0.2, 0.4, 0.5 and 1.0 mM as lead nitrate. At d 75 (34 days after metal exposure), the lead toxicity symptoms as restricted growth was observed on plants at 1.0 mM lead supply. Excess lead (0.5 and 1.0 mM) developed interveinal chlorosis along the margins of young leaves. The affected leaves were reduced in size giving plant a rosette like appearance. Head size was markedly reduced at these (0.5 and 1.0 mM) levels of lead. At 0.5 mM the intensity of symptoms was markedly low. With an increase in lead supply, the concentration of lead and zinc was increased whereas that of P, S, Fe, Mn and Cu were decreased in various parts of cabbage. At 1.0 mM Pb, the concentration of lead was highest in roots and lowest in head. In leaves of cabbage the threshold of toxicity and toxicity values were 150 and 320 microg g-1 dry matter, respectively.


Assuntos
Brassica , Chumbo/toxicidade , Micronutrientes/metabolismo , Nitratos/toxicidade , Poluentes do Solo/toxicidade , Brassica/efeitos dos fármacos , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
20.
Arch Womens Ment Health ; 7(1): 37-47, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14963731

RESUMO

Premenstrual dysphoric disorder (PMDD) can occur co-morbidly with other axis I disorders, particularly mood and anxiety disorders. The data supporting this diagnostic dilemma are reviewed in terms of methodological comparisons between studies. The point prevalence of the co-occurrence of PMDD and other psychiatric disorders is discussed as well as implications for treatment and further study.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtornos do Humor/epidemiologia , Síndrome Pré-Menstrual/epidemiologia , Síndrome Pré-Menstrual/psicologia , Transtornos Psicóticos/epidemiologia , Transtornos de Ansiedade/complicações , Comorbidade , Feminino , Humanos , Transtornos do Humor/complicações , Síndrome Pré-Menstrual/complicações , Prevalência , Transtornos Psicóticos/complicações
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