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1.
Phytopathology ; 110(2): 406-417, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31535924

RESUMO

Heterodera glycines, the soybean cyst nematode, and Macrophomina phaseolina, causal agent of charcoal rot, are economically important soybean pathogens. The impact and effect of these pathogens on soybean yield in coinfested fields in the Midwest production region is not known. Both pathogens are soilborne, with spatially aggregated distribution and effects. Spatial regression analysis, therefore, is an appropriate method to account for the spatial dependency in either the dependent variable or regression error term from data produced in fields naturally infested with H. glycines and M. phaseolina. The objectives of this study were twofold: to evaluate the combined effect of H. glycines and M. phaseolina on soybean yield in naturally infested commercial fields with ordinary least squares and spatial regression models; and to evaluate, under environmentally controlled conditions, the combined effect of H. glycines and M. phaseolina through nematode reproduction and plant tissue fungal colonization. Six trials were conducted in fields naturally infested with H. glycines and M. phaseolina in Ohio. Systematic-grid sampling was used to determine the population densities of H. glycines and M. phaseolina, and soybean yield estimates. Though not used in any statistical analysis, M. phaseolina colony forming units from plant tissue, charcoal rot severity, and H. glycines type were also recorded and summarized. In two greenhouse experiments, treatments consisted of H. glycines alone, M. phaseolina alone, and coinfestation of soybean with both pathogens. Moran's I test indicated that the yield from five fields was spatially correlated (P < 0.05) and aggregated. In these fields, to account for spatial dependence, spatial regression models were fitted to the data. Spatial regression analyses revealed a significant interaction effect between H. glycines and M. phaseolina on soybean yield for fields with high initial population densities of both pathogens. In the greenhouse experiments, H. glycines reproduction was significantly (P < 0.05) reduced in the presence of M. phaseolina; however, soybean tissue fungal colonization was not affected by the presence of H. glycines. The direct mechanisms by which H. glycines and M. phaseolina interact were not demonstrated in this study. Future studies must be conducted in the field and greenhouse to better understand this interaction effect.


Assuntos
Glycine max , Tylenchoidea , Animais , Ohio , Doenças das Plantas , Regressão Espacial
2.
Physiotherapy ; 106: 111-118, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-30992157

RESUMO

BACKGROUND: The Cystic Fibrosis Trust recently published a standards of care document which stated that patients should be given a physical activity (PA) programme based on their motivations, fitness, and willingness to be active. However, there remains much debate regarding the roles and responsibilities for PA promotion, as well as "optimal" recommendations and advice. This study aimed to qualitatively explore cystic fibrosis (CF) multidisciplinary teams (MDTs) advice, recommendations and practices relating to PA promotion for adolescents with CF. METHOD: Semi-structured interviews were conducted with fifteen members of CF MDTs (11 physiotherapists, two dieticians and two paediatricians). Thematic analysis was used to analyse the data. RESULTS: Major themes identified were: (1) structure of MDTs, (2) recommendations relating to intensities, durations and types of PA, and (3) use of exercise testing. Participants reported variation between MDTs in terms of who is responsible for promoting and supporting PA, the nature of advice given to patients, and the use of exercise testing. Participants consistently lacked confidence in their own or others' knowledge to provide standardised recommendations to patients and highlighted that PA promotion and support was often overlooked during busy periods. CONCLUSIONS: Despite its importance, PA support and promotion is not always prioritised. MDTs lack confidence in their ability to promote PA. Standardised advice and training relating to optimal intensities, durations and types of PA would provide a baseline from which to individualise advice to each patient and could increase confidence in PA promotion among MDTs.


Assuntos
Fibrose Cística/terapia , Exercício Físico , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Equipe de Assistência ao Paciente , Padrão de Cuidado , Adolescente , Humanos , Pesquisa Qualitativa , Reino Unido
3.
BMC Pulm Med ; 19(1): 220, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31771568

RESUMO

BACKGROUND: Physical activity is recommended in the management of cystic fibrosis (CF). The aim of this study was to explore motives, barriers and enablers to physical activity among this population. METHODS: Twelve participants (12-18 years) were recruited via convenience sampling. Photo-elicitation alongside semi-structured interviews were used to explore participants' views and experiences of physical activity. RESULTS: Our findings revealed motives for physical activity including health, enjoyment and autonomy. Those with families who valued physical activity tended to have positive attitudes towards physical activity, and valued and integrated it into their lives. Moreover, they were likely to be intrinsically motivated to be active. Several factors enable and act as barriers to physical activity. Whilst CF influenced physical activity, the majority of enablers and barriers raised where congruent with the general populations. CONCLUSION: This study provides support that healthcare providers should encourage both young people with CF and their families to be active, and subsequently informs the development of clinical interventions to support physical activity among young people with CF and their families.


Assuntos
Atitude Frente a Saúde , Fibrose Cística/psicologia , Fibrose Cística/reabilitação , Exercício Físico , Motivação , Adolescente , Atitude do Pessoal de Saúde , Criança , Feminino , Humanos , Entrevistas como Assunto , Masculino , Cooperação do Paciente , Pesquisa Qualitativa , Reino Unido
4.
J Pediatr Adolesc Gynecol ; 30(1): 63-70, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27543000

RESUMO

STUDY OBJECTIVE: To investigate the racial/ethnic differences in the correlates of spontaneous and medically-indicated late preterm birth (LPTB), defined as deliveries between 34 0/7 and 36 6/7 weeks gestation, among US adolescents. DESIGN: Population-based, retrospective cohort study. SETTING: Births in the United States to adolescents in 2012. PARTICIPANTS: Adolescents (younger than 20 years; n = 171,573) who delivered nonanomalous singleton first births between 34 and 44 weeks of gestation. INTERVENTIONS AND MAIN OUTCOME MEASURES: Bivariate and multivariable logistic regression were used to evaluate the associations between maternal risk factors and spontaneous and medically-indicated LPTB, stratified according to maternal race/ethnicity. RESULTS: Risk factors for spontaneous LPTB included single marital status among Asian adolescents; no insurance coverage among whites, Asian, and Hispanic adolescents; inadequate prenatal care among all racial/ethnic groups except American Indian, and adequate plus prenatal care among all races/ethnicities; prenatal smoking among whites and black adolescents; insufficient gestational weight gain among all racial/ethnic groups except American Indian; and prepregnancy underweight among white, black, and Hispanic adolescents. Risk factors for medically-indicated LPTB included inadequate prenatal care among white, black, and Hispanic adolescents, and adequate plus prenatal care among all racial/ethnic groups except Asian; insufficient gestational weight gain among white, black, and Hispanic adolescents; and prepregnancy overweight and obesity among white, black, and Hispanic adolescents. CONCLUSION: Our results show racial/ethnic differences in the correlates of spontaneous and medically-indicated LPTB among US adolescents and support the need for risk-specific interventions among different racial/ethnic groups.


Assuntos
Etnicidade/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Nascimento Prematuro/etnologia , Cuidado Pré-Natal/estatística & dados numéricos , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Asiático/estatística & dados numéricos , Feminino , Idade Gestacional , Hispânico ou Latino/estatística & dados numéricos , Humanos , Indígenas Norte-Americanos/estatística & dados numéricos , Recém-Nascido , Modelos Logísticos , Obesidade/complicações , Gravidez , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Fatores de Risco , Estados Unidos , População Branca/estatística & dados numéricos , Adulto Jovem
5.
Toxicol In Vitro ; 25(8): 2124-34, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22001958

RESUMO

The aim of this study was to investigate the transferability of technology and reproducibility of MUTZ-3 derived Langerhans Cell (MUTZ-LC) migration assay. The protocol was transferred from the NL-lab to two Sens-it-iv project partners (UK-lab, Italy-lab). Intra- and inter-laboratory variation with regards to MUTZ-3 progenitor culture, differentiation to MUTZ-LC, maturation and migration assay were investigated. In the transwell-migration-assay, preferential migration of sensitizer-exposed MUTZ-LC towards CXCL12 was observed (three sensitizers), whereas non-sensitizer-exposed MUTZ-LC only migrated towards CCL5 (two non-sensitizers). Four pre-pro-haptens were also identified by UK-lab. When taking the arbitrary criteria of at least two of three independent repetitions per laboratory having to have a CXCL12/CCL5 ratio>1.1 for classification as a sensitizer, all sensitizers tested in all labs were easily distinguished from all non-sensitizers. The number of repetitions giving false negative or false positive was very low (only 7 out of a total of 54 repetitions), indicating that both intra- and inter-laboratory variation was extremely low. Even though only a few chemicals were tested in this study, we show clearly that the in vitro DC migration assay is transferable between laboratories. The results were consistent between the laboratories, and the dose response data were reproduced in the three laboratories.


Assuntos
Alérgenos/imunologia , Ensaios de Migração Celular , Haptenos/imunologia , Células de Langerhans/imunologia , Linhagem Celular Tumoral , Quimiocina CCL5/imunologia , Quimiocina CXCL12/imunologia , Humanos , Laboratórios , Células de Langerhans/citologia , Reprodutibilidade dos Testes , Transferência de Tecnologia
6.
Equine Vet J Suppl ; (38): 116-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21058992

RESUMO

REASONS FOR PERFORMING STUDY: Dietary intake and feeding management practices could affect the degree of physiological stress and subsequent performance of high level 3-day event horses. OBJECTIVES: To assess whether a relationship exists between dietary intake levels of selected nutrients and the inflammatory and antioxidant status in horses competing in a high level 3-day event. MATERIALS AND METHODS: Riders competing in a CCI2*/CCI3* 3-day event (n = 35) answered a nutritional management survey conducted by the investigators at the competition. Actual and recommended intakes of vitamin E, potassium (K), calcium (Ca), phosphorus (P) and magnesium (Mg) were calculated using the manufacturer or NRC values. Blood samples, bodyweight and body condition score of horses were taken precompetition, 30 min and 18-24 h after cross-country, but before stadium jumping. Data were analysed using a mixed model ANOVA with repeated measures and Pearson's product moment correlation. RESULTS: Estimated daily intakes of vitamin E, K, Ca, P and Mg for horses were higher than daily recommended levels (P < 0.05). In response to competition, tumour necrosis factor-α (TNFα; P = 0.0002), nitric oxide (NO; P = 0.013) and ß-carotene (BC; P < 0.0001) decreased, creatine kinase (P < 0.0001) and aspartate aminotransferase (P = 0.001) increased, and α-tocopherol and retinol did not change. Intake of vitamin E, K, Ca, P and bodyweight were negatively correlated with TNFα (P < 0.05). Vitamin E and bodyweight were also negatively correlated with NO (P < 0.05). Pasture intake and BC were positively correlated (P < 0.0001). CONCLUSIONS: The decline in systemic inflammatory markers is probably due to increased utilisation or excretion and decreased production related to the increased oxidative stress experienced by horses during competition. High bodyweights could also predispose horses to a higher level of inflammation during 3-day event competition.


Assuntos
Criação de Animais Domésticos , Antioxidantes/metabolismo , Ingestão de Alimentos/fisiologia , Cavalos/fisiologia , Inflamação/sangue , Condicionamento Físico Animal , Animais , Biomarcadores , Feminino , Masculino , Esportes
7.
Equine Vet J Suppl ; (38): 317-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21059024

RESUMO

REASONS FOR PERFORMING STUDY: Many nutraceuticals are used as equine supplements without their efficacy having been scientifically tested. Black tea, cranberries, orange peel and ginger are a few of those nutraceuticals that warrant further study. OBJECTIVE: To test the effects of single doses of black tea, cranberry, orange peel and ginger extract on markers of oxidative stress and antioxidant status following exercise in horses. METHODS: In Study 1, 9 mature, healthy but unfit Standardbred mares were administered 2 l of a control (water), orange peel extract (30 g extract) or decaffeinated black tea extract (28 g extract). In Study 2 the same mares were administered 2 l of a control (water), cranberry extract (30 g extract) or ginger extract (30 g extract). In each study, mares were given the extracts via nasogastric tube 1 h before performing a graded exercise test (GXT), in a randomised crossover design with at least 7 days between GXTs. Blood samples were collected at rest, at fatigue, and 1 and 24 h post exercise and analysed for lipid hydroperoxides (LPO), total glutathione (GSH-T), glutathione peroxidase (GPx), α-tocopherol (TOC), ß-carotene (BC) and retinol. Data were statistically analysed using a repeated measures ANOVA. RESULTS: In Study 1 there was no effect of treatment for LPO, GSH-T, GPx, TOC or BC. Retinol was higher for both tea (P = 0.0006) and water (P = 0.004) than for orange peel. In Study 2 there was no treatment effect for LPO, GPx, GSH-T, RET, BC or TOC. CONCLUSIONS: The results show that a single dose of various nutraceuticals in exercising horses do not produce an effect on either oxidative stress or antioxidant status and further investigation is needed as to whether long-term supplementation would enhance these effects.


Assuntos
Cavalos/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Extratos Vegetais/farmacologia , Água/química , Animais , Antioxidantes/metabolismo , Estudos Cross-Over , Suplementos Nutricionais/análise , Feminino , Cavalos/sangue , Extratos Vegetais/química
8.
J Cyst Fibros ; 9(5): 302-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20359963

RESUMO

BACKGROUND: Exercise testing is a valuable prognostic tool and exercise training has many health benefits in cystic fibrosis (CF). The objective of this study was to survey the provision of exercise testing and training in UK CF clinics. METHODS: A three-page questionnaire was used to determine the extent of, scope and importance assigned to exercise testing and training. RESULTS: Data from returned questionnaires showed that 38.9% of paediatric and 27.8% of adult patients had performed an exercise test in the preceding 12 months, most as part of an annual review process. Pulmonary rehabilitation programmes were accessible in only 31.3% of clinics, and only 26.0% provide exercise training programmes. When assigning importance for exercise testing on a scale from 1 'not important' to 5 'very important', the mean and median respondent scores were 3.5 and 4.0, respectively, and for the importance of training were 4.0 and 4.0, respectively. CONCLUSIONS: Despite the level of importance given to exercise testing and training by healthcare providers, exercise is underused as either an assessment tool or therapeutic intervention in the healthcare of patients with CF in the UK.


Assuntos
Fibrose Cística/diagnóstico , Fibrose Cística/reabilitação , Teste de Esforço , Ambulatório Hospitalar , Educação Física e Treinamento , Adulto , Criança , Teste de Esforço/estatística & dados numéricos , Humanos , Inquéritos e Questionários , Reino Unido
9.
Pediatr Pulmonol ; 44(5): 480-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19382220

RESUMO

The value of exercise testing as an objective measure of disease severity in patients with chronic chest diseases (CCD) is becoming increasingly recognized. The aim of this study was to investigate changes in oxygen uptake (VO2) during early recovery following maximal cardiopulmonary exercise testing (CPXT) in relation to functional capacity and markers of disease severity. Twenty-seven children with CCD (age 12.7 +/- 3.1 years; 17 female) [19 children with Cystic fibrosis (CF) (age 13.4 +/- 3.1 years; 10 female) and 8 with other stable non-CF chest diseases (NON-CF) (age 11.1 +/- 2.2 years; 7 female)] and 27 healthy controls (age 13.2 +/- 3.3 years; 17 female) underwent CPXT on a cycle ergometer. On-line respiratory gas analysis measured VO2 before and during CPXT to peak VO2) (VO2(peak)), and during the first 10 min of recovery. Early VO2 recovery was quantified by the time (sec) to reach 50% of the VO2 (peak) value. Early VO2 recovery was correlated against spirometry [forced expiratory volume in 1 sec (FEV(1)) and forced expiratory flow between 25% and 75% of the forced vital capacity (FEF(25-75))] and aerobic fitness (VO2)(peak)) as a measure of functional capacity. Disease severity was graded in the CF patients by the Shwachman score (SS). Compared to controls, children with CCD demonstrated a significantly reduced VO2(peak) (P = 0.011), FEV(1) (P < 0.001), FEF(25-75) (P < 0.001), and a significantly prolonged early (VO2) recovery (P = 0.024). In the CF patients the SS was significantly correlated with early VO2 recovery (r = -0.63, P = 0.004), FEV(1) (r = 0.72, P = 0.001), and FEF(25-75) (r = 0.57, P = 0.011). In the children with CCD, FEV(1), FEF(25-75), and BMI were not significantly correlated with VO2(peak) or early VO2 recovery. Lung function does not necessarily reflect aerobic fitness and the ability to recover from exercise in these patients. A significant relationship was found between VO2(peak) and early VO2 recovery (r = -0.39, P = 0.044) in the children with CCD, showing that a greater aerobic fitness corresponded with a faster recovery.


Assuntos
Bronquiectasia/fisiopatologia , Fibrose Cística/fisiopatologia , Tolerância ao Exercício/fisiologia , Consumo de Oxigênio/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Teste de Esforço , Feminino , Humanos , Masculino , Ventilação Pulmonar/fisiologia
10.
Anticancer Agents Med Chem ; 8(2): 171-85, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18288920

RESUMO

Because invasion is, either directly or via metastasis formation, the main cause of death in cancer patients, development of efficient anti-invasive agents is an important research challenge. We have established a screening program for potentially anti-invasive compounds. The assay is based on organotypic confronting cultures between human invasive cancer cells and a fragment of normal tissue in three dimensions. Anti-invasive agents appeared to be heterogeneous with regard to their chemical nature, but plant alkaloids, polyphenolics and some of their synthetic congeners were well represented. Even within this group, active compounds were quite diverse: (+)-catechin, tangeretin, xanthohumol and other prenylated chalcones, 3,7-dimethoxyflavone, a pyrazole derivative, an isoxazolylcoumarin and a prenylated desoxybenzoin. The data gathered in this system are now applied in two projects. Firstly, structure-activity relationships are explored with computer models using an artificial neural network approach, based on quantitative structural descriptors. The aim of this study is the prediction and design of optimally efficient anti-invasive compounds. Secondly, the metabolism of orally ingested plant polyphenolics by colonic bacteria is studied in a simulator of the human intestinal microbial ecosystem (SHIME) and in human intervention trials. This method should provide information on the final bioavailability of the active compounds in the human body, with regard to microbial metabolism, and the feasibility of designing pre- or probiotics that increase the generation of active principles for absorption in the gastro-intestinal tract. The final and global aim of all these studies is to predict, synthesize and apply in vivo molecules with an optimal anti-invasive, and hence an anti-metastatic activity against cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Invasividade Neoplásica/prevenção & controle , Metástase Neoplásica/prevenção & controle , Neoplasias/tratamento farmacológico , Fenóis/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Proliferação de Células/efeitos dos fármacos , Flavonoides/química , Flavonoides/metabolismo , Humanos , Estrutura Molecular , Fenóis/química , Fenóis/metabolismo , Plantas/química , Polifenóis
11.
J Anim Sci ; 86(3): 576-83, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18156356

RESUMO

Eight mature (12 +/- 2 yr; MAT) and 5 older (22 +/- 2 yr; OLD) Standardbred mares were used to test the hypothesis that aging and exercise training would alter apoptosis in white blood cells and antioxidant status. The horses were housed indoors overnight (16 h/d) in 3 m x 3 m stalls and were turned out in a drylot during the day. They were fed a diet consisting of total mixed ration, hay cubes fed ad libitum or an equine senior diet plus grass hay. Horses were trained for 20 to 30 min/d, 3 to 5 d/wk for 8 wk at a submaximal work intensity between 60 to 70% of maximal heart rate. A graded exercise test (GXT; stepwise test until exhaustion) was performed before (GXT1) and after (GXT2) the 8 wk of training. During the GXT, blood samples and heart rate were taken at rest, 6 m/s, fatigue, and at 5 and 60 min postfatigue. Fatigue plasma lactate concentration was greater in MAT (19.3 +/- 1.5 at 10 m/s) compared with the OLD (10.9 +/- 1.2 mmol/L at 9 m/s; P = 0.008) horses. There was no effect of age or training on plasma lipid hydroperoxide (LPO) concentration. However, there was a positive correlation between LPO and plasma lactate concentration (r = 0.27, P = 0.006) during acute exercise. There was a greater concentration of total glutathione after GXT1 than after GXT2 (111.8 +/- 5.0 vs. 98.6 +/- 3.4 microM, respectively; P = 0.0002) for both age groups. Apoptosis was less (P = 0.002) in white blood cells of the MAT vs. the OLD group. These results demonstrate that older horses are under similar amounts of oxidative stress, measured by LPO, and have similar levels of glutathione in their systems compared with mature horses. The observation that more glutathione was needed during GXT1 for both groups of horses indicates that training helps horses adapt their system for the intense post-training exercise tests. The greater level of white blood cell apoptosis also indicates that older horses may be immune-compromised during exercise. However, research still needs to be performed regarding dietary supplementation in the aged horse.


Assuntos
Apoptose/fisiologia , Cavalos/fisiologia , Condicionamento Físico Animal/fisiologia , Fatores Etários , Ração Animal/análise , Animais , Eritrócitos/química , Feminino , Glutationa/sangue , Glutationa Peroxidase/sangue , Ácido Láctico/sangue , Leucócitos/fisiologia , Peróxidos Lipídicos/sangue , Condicionamento Físico Animal/métodos , Fatores de Tempo
12.
Int J Sports Med ; 28(4): 300-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17024627

RESUMO

Few studies have focused on the metabolic responses to alternating high- and low-intensity exercise and, specifically, compared these responses to those seen during constant-load exercise performed at the same average power output. This study compared muscle metabolic responses between two patterns of exercise during which the intensity was either constant and just below critical power (CP) or that oscillated above and below CP. Six trained males (mean +/- SD age 23.6 +/- 2.6 y) completed two 30-minute bouts of cycling (alternating and constant) at an average intensity equal to 90 % of CP. The intensity during alternating exercise varied between 158 % CP and 73 % CP. Biopsy samples from the vastus lateralis muscle were taken before (PRE), at the midpoint and end (POST) of exercise and analysed for glycogen, lactate, PCr and pH. Although these metabolic variables in muscle changed significantly during both patterns of exercise, there were no significant differences (p > 0.05) between constant and alternating exercise for glycogen (PRE: 418.8 +/- 85 vs. 444.3 +/- 70; POST: 220.5 +/- 59 vs. 259.5 +/- 126 mmol x kg (-1) dw), lactate (PRE: 8.5 +/- 7.7 vs. 8.5 +/- 8.3; POST: 49.9 +/- 19.0 vs. 42.6 +/- 26.6 mmol x kg (-1) dw), phosphocreatine (PRE: 77.9 +/- 11.6 vs. 75.7 +/- 16.9; POST: 65.8 +/- 12.1 vs. 61.2 +/- 12.7 mmol x kg (-1) dw) or pH (PRE: 6.99 +/- 0.12 vs. 6.99 +/- 0.08; POST: 6.86 +/- 0.13 vs. 6.85 +/- 0.06), respectively. There were also no significant differences in blood lactate responses to the two patterns of exercise. These data suggest that, when the average power output is similar, large variations in exercise intensity exert no significant effect on muscle metabolism.


Assuntos
Ciclismo/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Adulto , Análise de Variância , Glicogênio/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lactatos/metabolismo , Masculino , Fosfocreatina/metabolismo
13.
Equine Vet J Suppl ; (36): 617-21, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17402493

RESUMO

REASONS FOR PERFORMING STUDY: Vitamin E is the most commonly supplemented antioxidant in horses; however, previous research is not conclusive as to the recommended level for exercising horses. OBJECTIVE: To evaluate the effects of 3 levels of vitamin E supplementation on oxidative stress and vitamin/antioxidant status in intensely exercised horses to determine the optimal level of vitamin E supplementation. METHODS: Twelve unfit Standardbreds were divided into 3 groups, supplemented orally with 0 (CON), 5000 (MOD), or 10,000 (HI) iu/day of DL-alpha-tocopheryl acetate. The 3 x 3 Latin square design consisted of three 4 week supplementation periods with 4 week wash out periods between. After each period, horses underwent a treadmill interval exercise test. Blood samples were collected and heart rate (HR) measured before, during and after exercise. Data were analysed using ANOVA with repeated measures in SAS. RESULTS: The CON group had lower HR throughout the test compared to the MOD and HI groups (P<0.05). There was an increase in plasma retinol (RET), beta-carotene (BC), red blood cell total glutathione and glutathione peroxidase with exercise (P<0.05), but all groups returned to baseline after 24 h. Plasma alpha-tocopherol (TOC) increased from baseline with exercise (P<0.0001) in all groups; treatment differences were observed at 24 h (P<0.05). The HI and CON groups had lower BC compared to the MOD group (P = 0.05). CONCLUSIONS: Horses supplemented with vitamin E, at nearly 10-times the 1989 NRC recommended level, did not experience lower oxidative stress compared to control horses. Additionally, lower plasma BC levels observed in the HI group, which may indicate that vitamin E has an inhibitory effect on BC metabolism. POTENTIAL RELEVANCE: Supplementation above control levels is not more beneficial to oxidative stress and antioxidant status in intensely exercising horses; indeed, levels 10 times in excess may be detrimental to BC and should be avoided.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Antioxidantes/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Vitamina E/administração & dosagem , beta Caroteno/antagonistas & inibidores , Administração Oral , Análise de Variância , Animais , Antioxidantes/metabolismo , Estudos Cross-Over , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Teste de Esforço/veterinária , Feminino , Frequência Cardíaca/fisiologia , Cavalos , Estado Nutricional , Vitamina E/sangue , beta Caroteno/sangue , beta Caroteno/metabolismo
14.
J Anim Sci ; 82(2): 588-94, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14974559

RESUMO

This study tested the development of oxidative stress and the effects of antioxidant supplementation in an 80-km ride. A precompetition survey revealed that no competitor would participate without vitamin E supplementation; therefore, 46 horses were paired for past performances and randomly assigned to two groups of 23 each for 3 wk of supplementation before the ride. One group (E) was orally supplemented with 5,000 IU of vitamin E per day; the other group (E+C) received that dose of vitamin E plus 7 g/d of vitamin C. Blood samples, temperature, and heart rate were taken the day before the race, at 21 and 56 km during the ride, at completion, and after 20 min of recovery. Plasma was assayed for lipid hydroperoxides, alpha-tocopherol, total ascorbate, albumin, creatine kinase (CK), and aspartate aminotransferase (AST). Total glutathione and glutathione peroxidase activity were determined in red blood cells and white blood cells. Thirty-four horses completed the race, 12 horses (six in E and six in E+C) did not finish for reasons including lameness, metabolic problems, and rider option. Plasma ascorbate was higher (P = 0.045) in the E+C group than in the E group. Other than ascorbate, neither antioxidant status nor CK and AST activities were affected by supplementation with E+C vs. E. Red blood cell glutathione peroxidase, white blood cell total glutathione, lipid hydroperoxides, CK, and AST increased, and red blood cell total glutathione and white blood cell glutathione peroxidase activity decreased with distance (P < 0.001). Positive correlations were found for plasma lipid hydroperoxides on CK (r = 0.25; P = 0.001) and AST (r = 0.33; P < 0.001). These results establish an association between muscle leakage and a cumulative index of oxidative stress.


Assuntos
Antioxidantes/farmacologia , Cavalos/fisiologia , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Bem-Estar do Animal , Animais , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Aspartato Aminotransferases/metabolismo , Creatina Quinase/metabolismo , Suplementos Nutricionais , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Resistência Física/fisiologia , Distribuição Aleatória , Corrida/fisiologia , Vitamina E/administração & dosagem , Vitamina E/farmacologia
15.
Phytochemistry ; 55(6): 481-504, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11130659

RESUMO

Some of the recent advances in flavonoid research are reviewed. The role of anthocyanins and flavones in providing stable blue flower colours in the angiosperms is outlined. The contribution of leaf flavonoids to UV-B protection in plants is critically discussed. Advances in understanding the part played by flavonoids in warding off microbial infection and protecting plants from herbivory are described. The biological properties of flavonoids are considered in an evaluation of the medicinal and nutritional values of these compounds.


Assuntos
Flavonoides/fisiologia , Animais , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Congêneres do Estradiol/farmacologia , Flavonoides/farmacologia , Humanos , Plantas/efeitos da radiação , Protetores contra Radiação/farmacologia , Pesquisa
16.
Brain Res ; 852(2): 424-35, 2000 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-10678770

RESUMO

This study compared whether activation of muscle ergoreceptor afferents caused by isometric muscle contraction, activation of baroreceptor afferents induced by i.v. infusion of phenylephrine, or baroreceptor afferent inactivation, caused by carotid artery occlusion, elicit similar patterns of c-Fos induction in brainstem areas. Adult cats were anesthetized with alpha-chloralose, and in each case, the experimental intervention caused an increase in the arterial blood pressure. There were two sets of control experiments: in both, animals underwent the same surgical procedures but then either remained at rest for the entire study, or the tibial nerve was stimulated, as in the contraction group, following muscle paralysis with tubocurarine. Following the procedures, animals rested for 90 min to allow neuronal expression of c-Fos. Control cats showed very little c-Fos immunoreactivity (c-Fos-ir) in the brainstem. Muscle contraction induced c-Fos-ir expression mainly in the nucleus tractus solitarius, lateral reticular nucleus, lateral tegmental field, vestibular nucleus, subretrofacial nucleus, spinal trigeminal tract and in a lateral region of the periaqueductal grey (P 0.5-1.0). The majority of the c-Fos-ir was found in brainstem areas contralateral to the contracted muscle. In addition, muscle contraction induced c-Fos-ir in the dorsal horns of spinal segments L6-S1 on the ipsilateral side of the spinal cord. Phenylephrine infusion caused c-Fos-ir expression in the nucleus tractus solitarius, spinal trigeminal tract, solitary tract, and dorsal motor nucleus of the vagus. No c-Fos-ir was apparent in the periaqueductal grey. Carotid occlusions induced c-Fos-ir expression in the area postrema, nucleus tractus solitarius, solitary tract, and spinal trigeminal tract. Expression was bilateral. Areas that exhibited c-Fos-ir correspond to sites previously reported to release various neuropeptides in response to muscle contraction or carotid occlusions. These results indicate that the exercise pressor reflex and baroreflex activate similar, but not completely identical, sites in the brainstem.


Assuntos
Pressão Sanguínea/fisiologia , Tronco Encefálico/fisiologia , Contração Isométrica/fisiologia , Pressorreceptores/fisiologia , Proteínas Proto-Oncogênicas c-fos/biossíntese , Vias Aferentes/fisiologia , Animais , Anticorpos , Tronco Encefálico/irrigação sanguínea , Tronco Encefálico/química , Artérias Carótidas , Gatos , Estimulação Elétrica , Feminino , Ataque Isquêmico Transitório/fisiopatologia , Fármacos Neuromusculares não Despolarizantes/farmacologia , Fenilefrina/farmacologia , Pressorreceptores/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/imunologia , Reflexo/fisiologia , Simpatomiméticos/farmacologia , Nervo Tibial/fisiologia , Tubocurarina/farmacologia
17.
Poult Sci ; 77(7): 1036-44, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9657617

RESUMO

Turkey peritoneal exudate cells (PEC) and spermiophages (SMO) were assayed for characteristics of macrophages. The PEC elicited by i.p. injection of 3% Sephadex and SMO isolated from semen using Percoll were cultured in Dulbecco's Modified Eagle Medium supplemented with 20% bovine calf serum (DMEM-20) for 24 h at 41 C in 5% CO2 to provide adherent cells for assays. Most PEC and SMO showed esterase activity (99.3 +/- 0.6 and 98.8 +/- 0.9%, respectively), and exhibited nonspecific phagocytosis of carbon (89.5 +/- 3.6 and 95.3 +/- 0.6%, respectively), zymosan (26.5 +/- 7.6 and 24.3 +/- 2.5%, respectively), bacteria (11.3 +/- 0.8 and 9.3 +/- 0.3%, respectively), and opsonized and nonopsonized SRBC. Maximum uptake of SRBC was seen by 2 h for PEC but not until 4 h for SMO. At time of maximum uptake, SRBC were noted in 35 to 40% of PEC but only in 15 to 20% of SMO. Turkey IgG-FITC bound to both PEC and SMO, but goat anti-turkey IgG-FITC bound only to SMO. Increased nitrite was found in turkey semen after 24 h storage, with highest levels in samples in which SMO were added. Nitrite production was demonstrated using adhered PEC, but SMO could not be tested due to low cell numbers. This research clearly identifies SMO as having macrophage-like activities. Accordingly, these cells may possess the ability to process and present antigen via histocompatibility receptors. Such activity could lead to immune directed responses, including antibody production or activation of cytotoxic T-lymphocytes.


Assuntos
Macrófagos/fisiologia , Sêmen/citologia , Perus , Animais , Eritrócitos/imunologia , Esterases/metabolismo , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Imunoglobulina G/sangue , Macrófagos Peritoneais/fisiologia , Masculino , Nitritos/metabolismo , Fagocitose , Receptores Fc/fisiologia , Ovinos
18.
Am J Med Genet ; 77(3): 198-200, 1998 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-9605586

RESUMO

Deficiency of methylenetetrahydrofolate reductase (MTHFR) is associated with a variable phenotype that includes mental retardation, gait abnormalities, and seizures. Many of the same clinical findings are also seen in patients with Angelman syndrome. We report on a patient with MTHFR deficiency who was initially diagnosed as having Angelman syndrome. This case illustrates that MTHFR deficiency can mimic the phenotype of Angelman syndrome and that MTHFR deficiency should be excluded in patients with manifestations of Angelman syndrome whose molecular studies of chromosome 15 are normal.


Assuntos
Síndrome de Angelman/diagnóstico , Homocistinúria/diagnóstico , Erros Inatos do Metabolismo/diagnóstico , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/deficiência , Síndrome de Angelman/genética , Criança , Diagnóstico Diferencial , Homocisteína/sangue , Homocisteína/urina , Humanos , Masculino , Metionina/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2) , Fenótipo , Vitamina B 12/metabolismo
19.
Am J Med Genet ; 77(1): 8-11, 1998 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-9557885

RESUMO

Velo-cardio-facial syndrome, DiGeorge syndrome, conotruncal anomaly face syndrome, tetralogy of Fallot, and pulmonary atresia with ventricular septal defect are all associated with hemizygosity of 22q11. While the prevalence of the deletions in these phenotypes has been studied, the frequency of deletions in patients presenting with velopharyngeal insufficiency (VPI) is unknown. We performed fluorescence in situ hybridization for locus D22S75 within the 22q11 region on 23 patients with VPI (age range 5-42 years) followed in the Craniofacial Clinic at the University of Florida. The VPI occurred either as a condition of unknown cause (n=16) or as a condition remaining following primary cleft palate surgery (n=7). Six of sixteen patients with VPI of unknown cause and one of seven with VPI following surgery had a deletion in the region. This study documents a high frequency of 22q11 deletions in those presenting with VPI unrelated to overt cleft palate surgery and suggests that deletion testing should be considered in patients with VPI.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Insuficiência Velofaríngea/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Florida/epidemiologia , Humanos , Hibridização in Situ Fluorescente , Masculino , Insuficiência Velofaríngea/epidemiologia
20.
Hum Mutat ; 11(5): 411, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10336779

RESUMO

Neurofibromatosis type 1 (NF1) is a dominant disorder caused by mutations in the NF1 gene; approximately 100 NF1 gene mutations have been published. The CpG C-to-T transition is a frequent mutation mechanism in genetic disorders. To estimate its frequency in NF1, we employed a PCR-restriction digestion method to examine 17 CpGs in 65 patients, and also screened for a CpG nonsense transition (R1947X) that occurs in 1-2% of patients. The analysis revealed disease-related CpG C-to-T transitions (including a nonsense mutation that may be as frequent as R1947X) as well as a benign variant and another mutation at a CpG. Four patients showed CpG mutations in analysis of 18 sites (17 surveyed by restriction digest, plus the R1947X assay), including three C-to-T transitions and one C-to-G transversion. These 18 sites represent one-fifth of the 91 CpGs at which a C-to-T transition would result in a nonsense or nonconservative missense mutation. Thus, it is feasible that the CpG mutation rate at NF1 might be similar to that seen in other disorders with a high mutation rate, and that recurrent NF1 mutations may frequently reside at CpG sites.


Assuntos
Citosina , Mutação/genética , Neurofibromatose 1/genética , Timina , Genes da Neurofibromatose 1/genética , Testes Genéticos , Humanos
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