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1.
Vet Surg ; 39(5): 638-43, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20459482

RESUMO

OBJECTIVES: To compare postoperative inflammatory responses in horses administered perioperative procaine penicillin and those not administered penicillin using acute phase protein serum amyloid A (SAA) as a marker of inflammation. STUDY DESIGN: Randomized clinical trial. ANIMALS: Stallions (n=50) castrated under field conditions. METHODS: SAA concentrations were determined on days 0, 3, and 8. Six horses were subsequently excluded because of elevated SAA concentrations on day 0. Of the remaining 50 horses, 26 were administered nonsteroidal anti-inflammatory drug (NSAID) therapy and 24 were administered NSAID and 25,000 U/kg procaine penicillin on day 0, 1, and 2. RESULTS: SAA concentrations increased significantly from preoperative levels in both groups, and on day 8 concentrations were significantly (P<.02) higher in horses administered only NSAID than in those administered procaine penicillin and NSAID. Infectious complications occurred more frequently (P<.01) in horses with preoperatively elevated SAA concentrations (the excluded horses) than in horses with normal preoperative SAA concentrations (the included horses). CONCLUSIONS: Perioperative antimicrobial therapy reduced the postoperative SAA response, suggesting that bacteria were present in the surgical wound and contributed to inflammation after castration. Horses with elevated preoperative SAA concentrations developed infectious complications more often than horses with normal preoperative SAA concentrations. CLINICAL RELEVANCE: Administration of antimicrobials may be important in horses being castrated standing under field conditions. Increased SAA concentrations seem to be an indicator of increased surgical risk in horses and may be useful before elective surgery for planning.


Assuntos
Antibioticoprofilaxia/veterinária , Cavalos/cirurgia , Orquiectomia/veterinária , Penicilina G Procaína/uso terapêutico , Proteína Amiloide A Sérica/análise , Infecção da Ferida Cirúrgica/veterinária , Animais , Antibioticoprofilaxia/métodos , Masculino , Orquiectomia/efeitos adversos , Orquiectomia/métodos , Assistência Perioperatória/veterinária , Período Pós-Operatório , Postura , Infecção da Ferida Cirúrgica/prevenção & controle
2.
Lifetime Data Anal ; 16(1): 85-101, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19701708

RESUMO

We consider the situation with a survival or more generally a counting process endpoint for which we wish to investigate the effect of an initial treatment. Besides the treatment indicator we also have information about a time-varying covariate that may be of importance for the survival endpoint. The treatment may possibly influence both the endpoint and the time-varying covariate, and the concern is whether or not one should correct for the effect of the dynamic covariate. Recently Fosen et al. (Biometrical J 48:381-398, 2006a) investigated this situation using the notion of dynamic path analysis and showed under the Aalen additive hazards model that the total effect of the treatment indicator can be decomposed as a sum of what they termed a direct and an indirect effect. In this paper, we give large sample properties of the estimator of the cumulative indirect effect that may be used to draw inferences. Small sample properties are investigated by Monte Carlo simulation and two applications are provided for illustration. We also consider the Cox model in the situation with recurrent events data and show that a similar decomposition of the total effect into a sum of direct and indirect effects holds under certain assumptions.


Assuntos
Modelos Estatísticos , Processos Estocásticos , Análise de Sobrevida , Simulação por Computador , Feminino , Humanos , Longevidade , Masculino , Método de Monte Carlo , Resultado do Tratamento
3.
Vet J ; 258: 105457, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32564867

RESUMO

In young Cavalier King Charles spaniels (CKCS), intermittent mitral regurgitation (iMR; defined as moderate to severe mitral regurgitation [MR] in a small proportion of heartbeats), has been associated with an increased risk of cardiac death due to myxomatous mitral valve disease (MMVD). It is associated with increased R-R interval variability. Little is known about response to physiological factors and whether iMR is a precursor for developing significant MR. The aim of this study was to determine the effect of stress testing on the presence of iMR and heart rate, and short-term (1-2 year) progression of MR in CKCS with and without iMR. In total, 52 CKCS were included. Substudy 1 enrolled six dogs with iMR and 11 dogs without iMR. Substudy 2 enrolled 14 dogs with iMR and 28 dogs without iMR. Substudy 1 prospectively assessed the influence of stress testing on the presence of iMR and heart rate. Substudy 2 retrospectively evaluated short-term progression of iMR. During stress testing, iMR disappeared in 50% of CKCS and no iMR was recorded at mean heart rates >150 beats/min. Heart rate response did not differ between CKCS with or without iMR. CKCS with iMR did not have a higher odds (odds ratio = 5.2; 95% confidence interval, 0.7-38.2) of MR progression compared to controls (P = 0.1). In conclusion, physical stress influenced the occurrence of iMR in CKCS, but heart rate response was not different from CKCS without iMR. Intermittent mitral regurgitation did not significantly predict short-term MR progression. In stressed CKCS with early disease, iMR may be overlooked.


Assuntos
Progressão da Doença , Doenças do Cão/patologia , Teste de Esforço/veterinária , Frequência Cardíaca , Insuficiência da Valva Mitral/veterinária , Animais , Cães , Feminino , Masculino , Insuficiência da Valva Mitral/patologia
4.
Surg Endosc ; 21(5): 785-92, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17160494

RESUMO

BACKGROUND: Thoracoscopy has been shown to reduce the inflammatory and immunologic response to surgical stress, as compared with corresponding open procedures in humans. The influence on the hemostatic system, however, has not been thoroughly evaluated. The current study aimed to compare the perioperative and immediate postoperative changes in cellular, hemostatic, and inflammatory parameters after a partial pericardectomy performed by either thoracoscopy or thoracotomy. METHODS: For this study, 16 pigs were randomly assigned to have a partial pericardectomy performed thoracoscopically or by thoracotomy. Blood was collected intraoperatively, then 10 min, 3 h, and 6 h after surgery. Whole ethylenediaminetetraacetic acid (EDTA)-stabilized blood and plasma were examined for cellular, hemostatic, and inflammatory parameters, respectively, and thromboelastography (TEG) was performed on citrated whole blood. RESULTS: No significant difference in any of the parameters measured was found between the two groups except for the TEG parameter R-time, which was significantly shorter in the thoracoscopic group 3 h postoperatively. In both groups, a significant postoperative state of hypercoagulability and increase in inflammatory parameters was found. Additionally, pig blood showed a high degree of hypercoagulability in preoperative measurements, as compared with other species. CONCLUSIONS: Partial pericardectomy performed by thoracotomy or thoracoscopy in pigs produces a surgical stress response of equal magnitude, as measured by cellular, hemostatic, and inflammatory changes.


Assuntos
Hemostasia , Inflamação/etiologia , Pericardiectomia/efeitos adversos , Estresse Fisiológico/patologia , Estresse Fisiológico/fisiopatologia , Toracoscopia/efeitos adversos , Toracotomia/efeitos adversos , Animais , Antitrombinas/metabolismo , Contagem de Células Sanguíneas , Testes de Coagulação Sanguínea , Proteína C-Reativa/metabolismo , Feminino , Fibrinogênio/metabolismo , Masculino , Estresse Fisiológico/complicações , Estresse Fisiológico/etiologia , Suínos , Tromboelastografia
5.
Transplant Proc ; 49(9): 2161-2168, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29149977

RESUMO

BACKGROUND: The lack of lung transplant donors has necessitated the use of donors with a smoking history and donors of older age. We have evaluated the effects of donor smoking history and age on recipient morbidity and mortality with baseline values of pulmonary function and survival free of chronic lung allograft dysfunction (CLAD) as morbidity variables. METHODS: This is a retrospective analysis of 588 consecutive lung transplant recipients and their corresponding 454 donors. Donors were divided into three groups: group 1 included smokers, group 2 nonsmokers, and group 3 had unknown smoking status; these were further divided into three age groups: group A: 0 to 39 years; group B: 40 to 54 years; and group C: ≥55 years. RESULTS: One hundred fifty-one donors were former or actual smokers, 175 were nonsmokers, and 128 had unknown smoking histories. Baseline forced expiratory volume in 1 second, forced vital capacity, and diffusion capacity of carbon monoxide were lowest in the groups who received lungs from a smoking donor. CLAD-free survival was identical in all smoking groups, and overall survival was better both for lungs from nonsmoking donors and donors with unknown smoking status compared to lungs from smoking donors. One hundred sixty-nine donors were in age group A, 203 in B, and 82 in C. Baseline forced expiratory volume in 1 second, forced vital capacity, and diffusion capacity of carbon monoxide were lowest in the groups who received lungs from donors older than 55 years. Overall survival as well as CLAD-free survival was significantly lower with donors ≥55 years. CONCLUSIONS: Donor smoking history and older donor age impact lung function, mortality, and CLAD-free survival after transplantation. Because of a shortage of organs, extended donor criteria may be considered while taking waiting list mortality into account.


Assuntos
Fatores Etários , Transplante de Pulmão/mortalidade , Disfunção Primária do Enxerto/etiologia , Fumar/efeitos adversos , Doadores de Tecidos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Humanos , Lactente , Recém-Nascido , Pulmão/patologia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
6.
J Vet Intern Med ; 31(4): 1008-1016, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28573754

RESUMO

BACKGROUND: Development and progression of myxomatous mitral valve disease (MMVD) in dogs are difficult to predict. Identification at a young age of dogs at high risk of adverse outcome in the future is desirable. HYPOTHESIS/OBJECTIVES: To study the predictive value of selected clinical and echocardiographic characteristics associated with MMVD obtained at a young age for prediction of long-term cardiac and all-cause mortality in Cavalier King Charles Spaniels (CKCS). ANIMALS: 1125 privately owned CKCS. METHODS: A retrospective study including CKCS examined at the age of 1-3 years. Long-term outcome was assessed by telephone interview with owners. The value of variables for predicting mortality was investigated by Cox proportional hazard and Kaplan-Meier analyses. RESULTS: Presence of moderate to severe mitral regurgitation (MR) (hazard ratio (HR) = 3.03, 95% confidence interval (95% CI) = 1.48-6.23, P = 0.0025) even intermittent moderate to severe MR (HR = 2.23, 95% CI = 1.48-6.23, P = 0.039) on color flow Doppler echocardiography was significantly associated with increased hazard of cardiac death. An interaction between MR and sex was significant for all-cause mortality (P = 0.035), showing that males with moderate to severe MR had a higher all-cause mortality compared to males with no MR (HR = 2.38, 95% CI = 1.27-4.49, P = 0.0071), whereas no difference was found between female MR groups. The risk of cardiac (HR = 1.37, 95% CI = 1.14-1.63, P < 0.001) and all-cause (HR = 1.13, 95% CI = 1.02-1.24, P = 0.016) mortality increased with increasing left ventricular end-systolic internal dimension normalized for body weight (LVIDSN ). CONCLUSIONS AND CLINICAL IMPORTANCE: Moderate to severe MR, even if intermittent, and increased LVIDSN in dogs <3 years of age were associated with cardiac death later in life in CKCS.


Assuntos
Doenças do Cão/fisiopatologia , Insuficiência da Valva Mitral/veterinária , Disfunção Ventricular Esquerda/veterinária , Animais , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/mortalidade , Cães , Ecocardiografia/veterinária , Feminino , Masculino , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Sístole/fisiologia , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/fisiopatologia
7.
J Vet Intern Med ; 30(1): 63-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26578464

RESUMO

BACKGROUND: Cavalier King Charles Spaniels (CKCS) are predisposed to myxomatous mitral valve disease (MMVD). Studies have indicated a strong genetic background. OBJECTIVE: The aim of this study was to evaluate the effect of a breeding scheme involving auscultation and echocardiography. ANIMALS: In the Danish Kennel Club mandatory breeding scheme, 997 purebred CKCS were examined during the period 2002-2011. Each dog was evaluated 1-4 times with a total of 1,380 examinations. METHODS: Auscultation and echocardiography were performed to evaluate mitral regurgitation murmur severity and degree of mitral valve prolapse (MVP). The odds of having mitral regurgitation murmur or MVP > grade 1 in 2010-2011 compared to 2002-2003 were estimated using logistic regression analysis including age and sex as covariates. Odds were estimated for dogs that were products of the breeding scheme (defined as dogs with both parents approved by the breeding scheme before breeding) and non-products of the breeding scheme (defined as dogs with at least 1 parent with unknown cardiac status). RESULTS: In 2010-2011, the odds of having mitral regurgitation murmur were 0.27 if dogs were a product of the breeding scheme compared with dogs in 2002-2003, reflecting a 73% decreased risk (P < .0001). If non-products of the breeding scheme examined in 2010-2011 were compared with dogs in 2002-2003, no difference in odds was found (P = .49). CONCLUSION AND CLINICAL IMPORTANCE: A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of MMVD over the 8- to 10-year period. Such a breeding scheme therefore is recommended for CKCS.


Assuntos
Cruzamento/normas , Doenças do Cão/genética , Predisposição Genética para Doença , Prolapso da Valva Mitral/veterinária , Animais , Cães , Prolapso da Valva Mitral/genética , Estudos Retrospectivos
8.
J Vet Cardiol ; 17 Suppl 1: S268-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26776585

RESUMO

OBJECTIVES: A missense mutation (A31P) in the cardiac myosin binding protein C gene has been associated with hypertrophic cardiomyopathy (HCM) in Maine Coon cats. The aim of this study was to investigate the effect of A31P on development of HCM, myocardial diastolic dysfunction detected by color tissue Doppler imaging and occurrence of cardiac death during longitudinal follow-up in a cohort of Maine Coon cats. ANIMALS: The original cohort comprised 282 cats (158 of wild-type genotype, 99 heterozygous for A31P and 25 homozygous for A31P). METHODS: Prospective longitudinal study including echocardiography and registration of survival. RESULTS: The median age at the initial examination was 1.7 years (range, 0.8-9.2 years) and 6.4% (18/282) of the cats were diagnosed with HCM. One hundred sixty-five cats were eligible for echocardiographic re-examination, and during an average follow-up period of 2.7 years an additional 6.7% (11/165) of the cats developed HCM. Survival data could be obtained for 262 of the cats originally included, and among these 9.2% (24/262) died of causes that met the study criteria for cardiac death. In the homozygous group 80% (20/25) of cats included were diagnosed with HCM and 48% (12/25) suffered cardiac death during follow-up. These results corresponded to a significantly higher risk for cats homozygous for A31P to develop HCM (p<0.001) and die from cardiac-related causes compared with both other genotypes (p<0.001). CONCLUSIONS: Homozygosity for A31P was associated with a high penetrance of HCM and a substantial risk for cardiac death in the study population.


Assuntos
Cardiomiopatia Hipertrófica/veterinária , Proteínas de Transporte/metabolismo , Doenças do Gato/genética , Animais , Cardiomiopatia Hipertrófica/genética , Proteínas de Transporte/genética , Gatos , Estudos de Coortes , Predisposição Genética para Doença , Genótipo , Estudos Longitudinais , Mutação , Razão de Chances , Fatores de Risco
9.
Vet J ; 203(2): 192-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25599900

RESUMO

Serotonin (5-hydroxytryptamine, 5-HT) signalling is implicated in the pathogenesis of myxomatous mitral valve disease (MMVD) through 5-HT1B receptor (R), 5-HT2AR and 5-HT2BR-induced myxomatous pathology. Based on increased tryptophan hydroxylase-1 (TPH-1) and decreased serotonin re-uptake transporter (SERT) in MMVD-affected valves, increased valvular 5-HT synthesis and decreased clearance have been suggested. It remains unknown how haemodynamic changes associated with mitral regurgitation (MR) affect 5-HT markers in the mitral valve, myocardium and circulation. Twenty-eight pigs underwent surgically induced MR or sham-operation, resulting in three MR groups: control (CON, n = 12), mild MR (mMR, n = 10) and severe MR (sMR, n = 6). The gene expression levels of 5-HT1BR, 5-HT2AR, 5-HT2BR, SERT and TPH-1 were analysed using quantitative PCR (qPCR) in the mitral valve (MV), anterior papillary muscle (AP) and left ventricle (LV). MV 5-HT2BR was also analysed with immunohistochemistry (IHC) in relation to histological lesions and valvular myofibroblasts. All 5-HTR mRNAs were up-regulated in MV compared to AP and LV (P <0.01). In contrast, SERT and TPH-1 were up-regulated in AP and LV compared to MV (P <0.05). In MV, mRNA levels were increased for 5-HT2BR (P = 0.02) and decreased for SERT (P = 0.03) in sMR vs. CON. There were no group differences in 5-HT2BR staining (IHC) but co-localisation was found with α-SMA-positive cells in 91% of all valves and with 33% of histological lesions. In LV, 5-HT1BR mRNA levels were increased in sMR vs. CON (P = 0.01). In conclusion, these data suggest that MR may affect mRNA expression of valvular 5-HT2BR and SERT, and left ventricular 5-HT1BR in some pigs.


Assuntos
Regulação da Expressão Gênica , Valvas Cardíacas/metabolismo , Insuficiência da Valva Mitral/genética , Miocárdio/metabolismo , Serotonina/genética , Animais , Feminino , Coração/fisiopatologia , Valvas Cardíacas/fisiopatologia , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/metabolismo , Serotonina/metabolismo , Suínos
10.
J Comp Pathol ; 129(2-3): 120-30, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12921717

RESUMO

Comparable pathological changes in the mitral valve have been described in dogs, pigs and human patients with myxomatous mitral valve disease (MMVD), i.e., primary mitral valve prolapse. The progressive myxomatous changes are probably a response to repeated impact on the leaflets, and endothelial stress or damage probably plays a central role in the pathogenesis. Little, however, is known about the vasoactive substances that mediate the subendothelial changes. The aim of this study was to investigate the expression of nitric oxide synthase (NOS) in canine mitral valve leaflets and to relate the findings to MMVD changes. The mitral valve was taken post mortem from 12 dogs (six males and six females) and a whole valve NADPH (the reduced form of nicotinamide-adenine dinucleotide phosphate) diaphorase (NADPH-d) reaction was performed. Macroscopical (semiquantitative) and microscopical (computer image analysis) evaluations of the staining due to NADPH-d activity were performed at four specific areas of the valve and related to microscopical signs of MMVD and gross signs of thickening or prolapse, or both. Macroscopically, the NADPH-d colour grade was correlated with the degree of MMVD (P=0.01). In addition, endothelial NADPH-d staining intensity was correlated with macroscopical signs of disease (P=0.004) as well as with collagen degeneration (P=0.008) and deposition of mucopolysaccharides (P=0.02). Age, gender and specific area of the valve did not seem to influence the NADPH-d activity. In conclusion, increased NADPH-d activity, suggesting increased NOS expression, was found in areas of the mitral valve with myxomatous changes. This indicates that nitric oxide (NO) may play a role in the pathogenesis of MMVD in dogs.


Assuntos
Neoplasias Cardíacas/veterinária , Doenças das Valvas Cardíacas/veterinária , Valva Mitral/enzimologia , Mixoma/veterinária , NADPH Desidrogenase/metabolismo , Óxido Nítrico Sintase/metabolismo , Animais , Colágeno/metabolismo , Cães , Feminino , Neoplasias Cardíacas/enzimologia , Neoplasias Cardíacas/patologia , Doenças das Valvas Cardíacas/enzimologia , Doenças das Valvas Cardíacas/patologia , Histocitoquímica/veterinária , Processamento de Imagem Assistida por Computador , Masculino , Valva Mitral/patologia , Mixoma/enzimologia , Mixoma/patologia
11.
Vet Rec ; 152(10): 293-7, 2003 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-12650472

RESUMO

Myxomatous mitral valve disease in dogs is heritable, and it is therefore important to detect the early signs of the disease. This study was conducted to assess the predictive value of early echocardiographic and auscultatory signs of mitral valve prolapse, measured in terms of the leaflet thickness, the area of the regurgitant jet, and the intensity of the murmur, on the increases in left ventricular end diastolic diameter (LVEDD) and left atrial diameter (LAD) in a population of 190 clinically healthy dachshunds followed up for three years. The most significant predictor of an increase in LVEDD was the interaction between the index of mitral valve prolapse and the area of the regurgitant jet (P < 0.0001). In dogs with a jet area greater than 50 per cent of the left atrium, the disease progressed more quickly in terms of increases in LVEDD in relation to the severity of the prolapse at the initial examination. In dogs with smaller jets, the initial prolapse index was not significantly associated with increases in LVEDD. The initial index of mitral valve prolapse, the area of the jet and the intensity of the heart murmur were all significant predictors of an increase in LAD.


Assuntos
Doenças do Cão/diagnóstico por imagem , Doenças do Cão/diagnóstico , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/veterinária , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Animais , Função Atrial , Doenças do Cão/epidemiologia , Doenças do Cão/fisiopatologia , Cães , Feminino , Átrios do Coração/fisiopatologia , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/fisiopatologia , Masculino , Valor Preditivo dos Testes , Ultrassonografia , Função Ventricular Esquerda
12.
Ugeskr Laeger ; 159(26): 4099-104, 1997 Jun 23.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9229867

RESUMO

The aim of the present study was critically to review how intentional weight loss in overweight and obesity influences mortality. No randomized weight loss intervention trial has included mortality as an end-point. However, even minor weight loss causes beneficial changes in risk factors for cardiovascular disease, whereas the vast majority of observational studies have linked weight loss to excess mortality. Most observational studies do not have information on intentionality of weight loss and suffer from other methodological limitations making inferences from these studies difficult. Given the available observational evidence, the possibility that intended weight loss may cause some increased mortality cannot be excluded. However, considering the totality of the evidence on effects of intended weight loss among overweight and obese subjects, there may be other benefits, such as: psycho-social and physical well-being, risk factor improvement, decreased morbidity, and in certain high-risk subgroups decreased mortality. Treatment of obesity is therefore recommended, particularly in the presence of risk factors or complications.


Assuntos
Nível de Saúde , Morbidade , Mortalidade , Redução de Peso , Humanos
13.
Biometrika ; 101(1): 237-244, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28669998

RESUMO

We consider additive hazard models (Aalen, 1989) for the effect of a randomized treatment on a survival outcome, adjusting for auxiliary baseline covariates. We demonstrate that the Aalen least squares estimator of the treatment effect parameter is asymptotically unbiased, even when the hazard's dependence on time or on the auxiliary covariates is misspecified, and even away from the null hypothesis of no treatment effect. We moreover show that adjustment for auxiliary baseline covariates does not change the asymptotic variance of the Aalen least squares estimator of the effect of a randomized treatment. We conclude that, in view of its robustness against model misspecification, Aalen least squares estimation is attractive for evaluating treatment effects on a survival outcome in randomized experiments, and that the primary reasons to consider baseline covariate adjustment in such settings may be the interest in subgroup effects, or the need to adjust for informative censoring or for baseline imbalances. Our results also shed light on the robustness of Aalen least squares estimators against model misspecification in observational studies.

14.
Matrix Biol ; 34: 96-104, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24080228

RESUMO

The growth hormone/insulin-like growth factor-I (GH/IGF-I) axis is an important stimulator of collagen synthesis in connective tissue, but the effect of chronically altered GH/IGF-I levels on connective tissue of the muscle-tendon unit is not known. We studied three groups of mice; 1) giant transgenic mice that expressed bovine GH (bGH) and had high circulating levels of GH and IGF-I, 2) dwarf mice with a disrupted GH receptor gene (GHR-/-) leading to GH resistance and low circulating IGF-I, and 3) a wild-type control group (CTRL). We measured the ultra-structure, collagen content and mRNA expression (targets: GAPDH, RPLP0, IGF-IEa, IGF-IR, COL1A1, COL3A1, TGF-ß1, TGF-ß2, TGF-ß3, versican, scleraxis, tenascin C, fibronectin, fibromodulin, decorin) in the Achilles tendon, and the mRNA expression was also measured in calf muscle (same targets as tendon plus IGF-IEb, IGF-IEc). We found that GHR-/- mice had significantly lower collagen fibril volume fraction in Achilles tendon, as well as decreased mRNA expression of IGF-I isoforms and collagen types I and III in muscle compared to CTRL. In contrast, the mRNA expression of IGF-I isoforms and collagens in bGH mice was generally high in both tendon and muscle compared to CTRL. Mean collagen fibril diameter was significantly decreased with both high and low GH/IGF-I signaling, but the GHR-/- mouse tendons were most severely affected with a total loss of the normal bimodal diameter distribution. In conclusion, chronic manipulation of the GH/IGF-I axis influenced both morphology and mRNA levels of selected genes in the muscle-tendon unit of mice. Whereas only moderate structural changes were observed with up-regulation of GH/IGF-I axis, disruption of the GH receptor had pronounced effects upon tendon ultra-structure.


Assuntos
Colágeno Tipo I/biossíntese , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Músculo Esquelético/metabolismo , Animais , Bovinos , Tecido Conjuntivo/metabolismo , Tecido Conjuntivo/ultraestrutura , Hormônio do Crescimento/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Transgênicos , Músculo Esquelético/ultraestrutura , Biossíntese de Proteínas , RNA Mensageiro/biossíntese , Tendões/metabolismo
15.
Eur J Clin Nutr ; 68(2): 189-95, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24219894

RESUMO

BACKGROUND/OBJECTIVES: The aim was to examine the causal effect of vitamin D on serum adiponectin using a multiple instrument Mendelian randomization approach. SUBJECTS/METHODS: Serum 25-hydroxy vitamin D (25(OH)D) and serum total or high molecular weight (HMW) adiponectin were measured in two Danish population-based studies: the Inter99 study (6405 adults, 30-60 years) conducted in 1999-2001, and the MONICA10 study (2656 adults, 41-71 years) conducted in 1993-1994. RESULTS: In the Inter99 study, serum 25(OH)D was positively associated with total adiponectin (the effect estimate in % per doubling of 25(OH)D was 4.78, 95% CI: 1.96, 7.68, P<0.001). Using variations in the vitamin D-binding protein gene and the filaggrin gene as instrumental variables, the causal effect in % was estimated to 61.46, 95% CI: 17.51, 120.28, P=0.003 higher adiponectin per doubling of 25(OH)D. In the MONICA10 cohort, no significant association was observed between the serum concentrations of 25(OH)D and HMW adiponectin (the effect estimate in % per doubling of 25(OH)D was -1.51, 95% CI: -5.80, 2.98, P=0.50), although the instrumental variables analysis to some extent supported a positive causal association (the effect estimate in % per doubling of 25(OH)D was 37.13, 95% CI: -3.67, 95.20, P=0.080). CONCLUSIONS: The results indicate a possible causal association between serum 25(OH)D and total adiponectin. However, the association was not replicated for HMW adiponectin. Thus, further studies are needed to confirm a causal relationship.


Assuntos
Adiponectina/sangue , Variação Genética , Análise da Randomização Mendeliana , Vitamina D/análogos & derivados , Adulto , Idoso , Antropometria , Dinamarca , Feminino , Proteínas Filagrinas , Genótipo , Humanos , Islândia , Proteínas de Filamentos Intermediários/genética , Masculino , Pessoa de Meia-Idade , Peso Molecular , Noruega , Suécia , Vitamina D/sangue , Vitamina D/genética , Proteína de Ligação a Vitamina D/genética
16.
Equine Vet J ; 45(5): 564-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23294287

RESUMO

REASONS FOR PERFORMING STUDY: Incisional infections are common in horses after colic surgery. There is a clinical impression that the use of a stent bandage reduces the prevalence of such infections. OBJECTIVE: To determine the effect of a stent bandage on the likelihood of incisional infection after ventral midline exploratory coeliotomy. It was hypothesised that the use of a stent bandage would reduce the likelihood of incisional infection. METHODS: Medical records of horses that underwent exploratory coeliotomy for colic between January 2005 and September 2011 were reviewed. Inclusion criteria were animals that had one ventral midline coeliotomy and had survived at least 10 days after surgery. Horses were categorised into 2 groups:no-stent group and stent group. The following data were collected for each case: age, sex, weight, heart rate, packed cell volume, primary lesion, performance of an enterotomy or intestinal resection, surgical classification, use of local antimicrobials, duration of surgery, intra-abdominal administration of sodium carboxymethylcellulose, intravenous administration of lidocaine, surgeon, use of a stent bandage, duration of stent use, and use of a belly band. Factors associated with the outcome measure 'wound infection' vs. 'no wound infection' were analysed using a generalised linear mixed model for logistic regression with surgeon as a random effect. RESULTS: The inclusion criteria were met in 130 horses: 55 were assigned to the no-stent group and 75 to the stent group. In the no-stent group, 12 (21.8%) horses developed incisional infections, whereas only 2 horses (2.7%) in the stent group had incisional infections. In the stent group, no incisional infections were observed during the last 20 months of the study. Statistical analysis showed that only the effect of the use of a stent bandage was significant (P = 0.005). CONCLUSIONS: The prevalence of incisional infections when a stent bandage was used was 2.7%, a finding that compared favourably to information in the literature. Use of a stent bandage significantly reduced the likelihood of incisional infections. POTENTIAL RELEVANCE: A stent bandage would reduce the likelihood of incisional infection in horses undergoing exploratory coeliotomy for colic.


Assuntos
Cólica/veterinária , Bandagens Compressivas/veterinária , Doenças dos Cavalos/cirurgia , Laparotomia/veterinária , Infecção da Ferida Cirúrgica/veterinária , Animais , Cólica/cirurgia , Feminino , Cavalos , Laparotomia/efeitos adversos , Masculino , Infecção da Ferida Cirúrgica/prevenção & controle , Resultado do Tratamento
17.
Acta Physiol (Oxf) ; 204(3): 371-81, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21791016

RESUMO

AIM: To examine whether inhalation of CO(2) -enriched gas would increase steady-state VO(2) during exercise and enlarge O(2) deficit. METHODS: Ten physically active men (VO(2) 53.7 ± 3.6 mL min(-1) kg(-1) ; x ± SD) performed transitions from low-load cycling (baseline; 40 W) to work rates representing light (≈ 45% VO(2); 122 ± 15 W) and heavy (≈ 80% VO(2); 253 ± 29 W) exercise while inhaling normal air (air) or a CO(2) mixture (4.2% CO(2) , 21% O(2) , balance N(2) ). Gas exchange was measured with Douglas bag technique at baseline and at min 0-2, 2-3 and 5-6. RESULTS: Inhalation of CO(2) -enriched air consistently induced respiratory acidosis with increases in PCO(2) and decreases in capillary blood pH (P < 0.01). Hypercapnic steady-state VO(2) was on average about 6% greater (P < 0.01) than with air in both light and heavy exercise, presumably because of increased cost of breathing (ΔVE 40-50 L min(-1) ; P < 0.01), and a substrate shift towards increased lipid oxidation (decline in R 0.12; P < 0.01). VO(2) during the first 2 min of exercise were not significantly different whereas the increase in VO(2) from min 2-3 to min 5-6 in heavy exercise was larger with CO(2) than with air suggesting a greater VO(2) slow component. As a result, O(2) deficit was greater with hypercapnia in heavy exercise (2.24 ± 0.51 L vs. 1.91 ± 0.45 L; P < 0.05) but not in light (0.64 ± 0.21 L vs. 0.54 ± 0.20 L; ns). CONCLUSION: Inhalation of CO(2)-enriched air and the ensuing respiratory acidosis increase steady-state VO(2) in both light and heavy exercise and enlarges O(2) deficit in heavy exercise.


Assuntos
Dióxido de Carbono/administração & dosagem , Exercício Físico , Hipercapnia/fisiopatologia , Contração Muscular , Músculo Esquelético/metabolismo , Consumo de Oxigênio , Equilíbrio Ácido-Base , Acidose Respiratória/sangue , Acidose Respiratória/fisiopatologia , Administração por Inalação , Adulto , Análise de Variância , Ciclismo , Frequência Cardíaca , Humanos , Concentração de Íons de Hidrogênio , Hipercapnia/sangue , Ácido Láctico/sangue , Metabolismo dos Lipídeos , Masculino , Oxirredução , Troca Gasosa Pulmonar , Fatores de Tempo , Adulto Jovem
18.
Animal ; 5(6): 851-60, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22440024

RESUMO

The restrictions on the use of antibiotic and anthelmintic treatments in organic pig farming necessitate alternative non-medical control strategies. Therefore, the antibiotic and parasite-reducing effect of a fructan-rich (prebiotic) diet of dried chicory was investigated in free-ranging piglets. Approximately half of 67 piglets from nine litters were experimentally infected with Ascaris suum and Trichuris suis in the suckling period (1 to 7 weeks of age) and 58 of the piglets were challenged daily with Eschericia coli O138:F8 for 9 days after weaning to induce weaning diarrhoea. The litters were fed either chicory (30% dry matter) or a control diet. The effect of chicory on intestinal helminths, intestinal microbiota, especially Bifidobacteria and Campylobacter spp. and E. coli post-weaning diarrhoea was assessed. The weight gain of the piglets was not impaired significantly by chicory. The intestinal A. suum worm burden was reduced by 64% (P = 0.034) in the chicory-fed piglets, whereas these same piglets had 63% more T. suis worms (P = 0.016). Feeding with chicory elicited no changes among the main bacterial groups in ileum according to terminal restriction fragment length polymorphism analysis. However, the terminal-restriction fragment (T-RF) 208 bp, which may belong to Lachnospiraceae, was stimulated by the chicory feed (P = 0.03), and T-RF 370 bp that matches Enterobacter belonging to the Enterobacteria was reduced (P = 0.004). In addition, chicory increased the level of Bifidobacteria (P = 0.001) and the faecal Campylobacter excretion level was transitorily reduced in chicory-fed piglets at 7 weeks of age (P = 0.029). Unfortunately, it was not possible to assess the effect of chicory on post-weaning diarrhoea as it did not develop. In conclusion, feeding piglets chicory around the time of weaning caused complex changes of the microbiota and parasite communities within the intestinal tract, and feeding piglets chicory may therefore serve as an animal-friendly strategy to control pathogens.

19.
Clin Nutr ; 28(3): 260-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19345452

RESUMO

BACKGROUND & AIMS: Bioactive ingredients have been shown to reduce appetite and energy intake. The magnitude of these effects might depend on energy balance why it was investigated how capsaicin, green tea, CH-19 sweet pepper as well as green tea and capsaicin affect appetite and energy intake during respectively negative and positive energy balance. METHODS: 27 subjects were randomized to three weeks of negative and three weeks of positive energy balance during which capsaicin, green tea, CH-19 sweet pepper, capsaicin+green tea or placebo was ingested on ten separate test days while the effects on appetite, energy intake, body weight and heart rate were assessed. RESULTS: CH-19 sweet pepper and a combination of capsaicin and green tea reduced energy intake during positive energy balance. Capsaicin and green tea suppressed hunger and increased satiety more during negative than during positive energy balance. CONCLUSIONS: Bioactive ingredients had energy intake reducing effects when used in combinations and in positive energy balance. Energy balance did not affect possible treatment induced energy intake, but did affect appetite by supporting negative energy balance. Bioactive ingredients may therefore be helpful in reducing energy intake and might support weight loss periods by relatively sustaining satiety and suppressing hunger.


Assuntos
Apetite/efeitos dos fármacos , Capsaicina/farmacologia , Capsicum , Ingestão de Energia/efeitos dos fármacos , Chá , Adulto , Apetite/fisiologia , Peso Corporal/efeitos dos fármacos , Capsicum/química , Estudos Cross-Over , Combinação de Medicamentos , Ingestão de Energia/fisiologia , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Obesidade/terapia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiologia , Chá/química
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