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2.
J Inherit Metab Dis ; 41(6): 1275-1283, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30167885

RESUMO

OBJECTIVES: To describe the spectrum of movement disorders and cerebrospinal fluid (CSF) neurotransmitter profiles in paediatric patients with POLG disease. METHODS: We identified children with genetically confirmed POLG disease, in whom CSF neurotransmitter analysis had been undertaken. Clinical data were collected retrospectively. CSF neurotransmitter levels were compared to both standardised age-related reference ranges and to non-POLG patients presenting with status epilepticus. RESULTS: Forty-one patients with POLG disease were identified. Almost 50% of the patients had documented evidence of a movement disorder, including non-epileptic myoclonus, choreoathetosis and ataxia. CSF neurotransmitter analysis was undertaken in 15 cases and abnormalities were seen in the majority (87%) of cases tested. In many patients, distinctive patterns were evident, including raised neopterin, homovanillic acid and 5-hydroxyindoleacetic acid levels. CONCLUSIONS: Children with POLG mutations can manifest with a wide spectrum of abnormal movements, which are often prominent features of the clinical syndrome. Underlying pathophysiology is probably multifactorial, and aberrant monoamine metabolism is likely to play a role.


Assuntos
Doenças Mitocondriais/líquido cefalorraquidiano , Transtornos dos Movimentos/etiologia , Neurotransmissores/líquido cefalorraquidiano , Adolescente , Criança , Pré-Escolar , DNA Polimerase gama/genética , Feminino , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Lactente , Masculino , Doenças Mitocondriais/genética , Mutação , Neopterina/líquido cefalorraquidiano , Estudos Retrospectivos
3.
Aust Vet J ; 92(7): 235-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24964831

RESUMO

OBJECTIVE: To evaluate the effectiveness of online audiovisual materials to support the acquisition of animal handling skills by students of veterinary and animal science. METHODS: A series of video clips (Livestock Handling modules) demonstrating livestock handling procedures was created and delivered online to students enrolled in the Faculty of Veterinary Science, University of Sydney. The effectiveness of these modules for supporting student learning was evaluated via an online survey. The survey also sought feedback on how students could be better prepared for handling livestock. RESULTS: The survey indicated that students found the videos a useful part of their learning experience, particularly by familiarising them with correct handling procedures and emphasising the importance of safety when handling livestock. Students also highlighted that online delivery supported flexible learning. Suggested improvements of the Livestock Handling modules centred around broadening the content of the videos and improving the user-friendliness of online access. Student feedback regarding how the Faculty could better prepare them for livestock handling was dominated by requests for more opportunities to practise animal handling using live animals. CONCLUSIONS: The Livestock Handling audiovisual tool is a valuable supplementary resource for developing students' proficiency in safe and effective handling of livestock. However, the results also clearly reveal a perception by students that more hands-on experience is required for acquisition of animal handling skills. These findings will inform future development of the Faculty's animal handling program.


Assuntos
Educação a Distância/métodos , Educação em Veterinária/métodos , Gado , Gravação em Vídeo , Criação de Animais Domésticos/métodos , Animais , Atitude do Pessoal de Saúde , Competência Clínica , Feminino , Inquéritos Epidemiológicos , Humanos , Internet , Masculino , New South Wales , Faculdades de Medicina Veterinária , Estudantes de Ciências da Saúde/psicologia , Estudantes de Ciências da Saúde/estatística & dados numéricos
4.
Math Biosci ; 241(1): 56-74, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23046704

RESUMO

This study develops a lumped cardiovascular-respiratory system-level model that incorporates patient-specific data to predict cardiorespiratory response to hypercapnia (increased CO(2) partial pressure) for a patient with congestive heart failure (CHF). In particular, the study focuses on predicting cerebral CO(2) reactivity, which can be defined as the ability of vessels in the cerebral vasculature to expand or contract in response CO(2) induced challenges. It is difficult to characterize cerebral CO(2) reactivity directly from measurements, since no methods exist to dynamically measure vasomotion of vessels in the cerebral vasculature. In this study we show how mathematical modeling can be combined with available data to predict cerebral CO(2) reactivity via dynamic predictions of cerebral vascular resistance, which can be directly related to vasomotion of vessels in the cerebral vasculature. To this end we have developed a coupled cardiovascular and respiratory model that predicts blood pressure, flow, and concentration of gasses (CO(2) and O(2)) in the systemic, cerebral, and pulmonary arteries and veins. Cerebral vascular resistance is incorporated via a model parameter separating cerebral arteries and veins. The model was adapted to a specific patient using parameter estimation combined with sensitivity analysis and subset selection. These techniques allowed estimation of cerebral vascular resistance along with other cardiovascular and respiratory parameters. Parameter estimation was carried out during eucapnia (breathing room air), first for the cardiovascular model and then for the respiratory model. Then, hypercapnia was introduced by increasing inspired CO(2) partial pressure. During eucapnia, seven cardiovascular parameters and four respiratory parameters was be identified and estimated, including cerebral and systemic resistance. During the transition from eucapnia to hypercapnia, the model predicted a drop in cerebral vascular resistance consistent with cerebral vasodilation.


Assuntos
Hipercapnia/fisiopatologia , Modelos Biológicos , Circulação Cerebrovascular , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Conceitos Matemáticos , Pessoa de Meia-Idade , Modelos Cardiovasculares , Fenômenos Fisiológicos Respiratórios , Resistência Vascular
5.
J Inherit Metab Dis ; 32(2): 269-73, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19169843

RESUMO

The pathogenesis of mitochondrial disorders has largely focused on the impairment of cellular energy metabolism. However, mitochondrial dysfunction has also been implicated as a factor in the initiation of apoptosis due to the translocation of cytochrome c, from mitochondria to the cytosol, and the subsequent cleavage of pro-caspase 3. In this study, we determined the cytochrome c content of cytosols (skeletal muscle) prepared from 22 patients with evidence of compromised mitochondrial electron transport chain enzyme activity and 26 disease controls. The cytochrome c content of the mitochondrial electron transport chain-deficient group was found to be significantly (p < 0.02) elevated when compared with the control group (63.7 +/- 15.5 versus 27.7 +/- 2.5 ng/mg protein). Furthermore, a relationship between the cytosolic cytochrome c content of skeletal muscle and complex I and complex IV activities was demonstrated. Such data raise the possibility that mitochondrial cytochrome c release may be a feature of mitochondrial disorders, particularly for those patients with marked deficiencies of respiratory chain enzymes. Whether initiation of apoptosis occurs as a direct consequence of this cytochrome c release has not been fully evaluated here. However, for one patient with the greatest documented cytosolic cytochrome c content, caspase 3 could be demonstrated in the cytosolic preparation. Further work is required in order to establish whether a relationship also exists between caspase 3 formation and the magnitude of respiratory chain deficiency.


Assuntos
Citocromos c/metabolismo , Mitocôndrias/enzimologia , Doenças Mitocondriais/enzimologia , Adolescente , Adulto , Caspase 3/metabolismo , Criança , Pré-Escolar , Citrato (si)-Sintase/metabolismo , Citosol/enzimologia , Transporte de Elétrons/fisiologia , Humanos , Indicadores e Reagentes , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/enzimologia , Adulto Jovem
6.
Environ Int ; 35(3): 485-90, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18793803

RESUMO

We investigated the effects of phosphorus (P) supply on the uptake and toxicity of arsenate (As(V)) in two plant species (Medicago truncatula and Hordeum vulgare) grown in soil/sand mixes. Our initial hypothesis was that competition between phosphate (Pi) and As(V) for uptake would be observed, and that this would be the basis for the 'protective' effect of P with respect to As toxicity, as shown in solution culture. Addition of P to the soil/sand mixes did not have major effects on water extractable As, or vice versa. We observed that toxic effects of As(V) on plant growth were ameliorated by increased P in both plant species. However, we found no evidence that increased P supply reduced specific uptake of As(V) on a molar basis, so that competition with Pi could not be the basis for the effect. A more complex mechanism of protection is indicated which might relate to different Pi transport systems being expressed at different P levels.


Assuntos
Arseniatos/metabolismo , Arseniatos/toxicidade , Hordeum/metabolismo , Medicago truncatula/metabolismo , Fosfatos/metabolismo , Poluentes do Solo/metabolismo , Hordeum/crescimento & desenvolvimento , Medicago truncatula/crescimento & desenvolvimento
7.
Phys Rev Lett ; 100(25): 254504, 2008 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-18643666

RESUMO

We present a collection of eight data sets from state-of-the-art experiments and numerical simulations on turbulent velocity statistics along particle trajectories obtained in different flows with Reynolds numbers in the range R{lambda}in[120:740]. Lagrangian structure functions from all data sets are found to collapse onto each other on a wide range of time lags, pointing towards the existence of a universal behavior, within present statistical convergence, and calling for a unified theoretical description. Parisi-Frisch multifractal theory, suitably extended to the dissipative scales and to the Lagrangian domain, is found to capture the intermittency of velocity statistics over the whole three decades of temporal scales investigated here.

8.
Nature ; 450(7170): 654-6, 2007 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-18046399

RESUMO

Venus has no significant internal magnetic field, which allows the solar wind to interact directly with its atmosphere. A field is induced in this interaction, which partially shields the atmosphere, but we have no knowledge of how effective that shield is at solar minimum. (Our current knowledge of the solar wind interaction with Venus is derived from measurements at solar maximum.) The bow shock is close to the planet, meaning that it is possible that some solar wind could be absorbed by the atmosphere and contribute to the evolution of the atmosphere. Here we report magnetic field measurements from the Venus Express spacecraft in the plasma environment surrounding Venus. The bow shock under low solar activity conditions seems to be in the position that would be expected from a complete deflection by a magnetized ionosphere. Therefore little solar wind enters the Venus ionosphere even at solar minimum.

9.
Burns ; 33(6): 747-55, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17707785

RESUMO

This study looks at the body image, mood and quality of life of a group of 36 young people aged between 11 and 19 years who had burns as children, compared with an age-matched control group of 41 young people who had not had these injuries. Participants completed the Body Esteem Scale (BES), the Satisfaction With Appearance Scale (SWAP), the Beck Depression Inventory-II (BDI-II) and the Youth Quality of Life Questionnaire (YQOL). It was hypothesised that young burn survivors would report more dissatisfaction with their appearance, a lower mood and a lower quality of life compared with non-injured controls. However, young burn survivors reported significantly more positive evaluations of how others view their appearance (p=0.018), more positive weight satisfaction (p=0.001) and a higher quality of life (p=0.005) than the control group. They also reported more positive general feelings about their appearance, although this was just below the level for statistical significance (p=0.067) and a similar mood to the school sample (p=0.824). The data suggest that young burn survivors appear to be coping well in comparison to their peers, and in some areas may be coping better, in spite of living with the physical, psychological and social consequences of burns.


Assuntos
Afeto , Imagem Corporal , Queimaduras/psicologia , Qualidade de Vida , Sobreviventes/psicologia , Adolescente , Adulto , Fatores Etários , Queimaduras/patologia , Criança , Feminino , Humanos , Masculino , Satisfação do Paciente
10.
J Nutr Health Aging ; 11(1): 55-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17315081

RESUMO

OBJECTIVE: To examine potential for bias in reported total energy intake on a Food Frequency Questionnaire (FFQ) among older adults. DESIGN: Longitudinal cohort study. SUBJECTS/SETTING: 2,706 Community-dwelling Black and White older adults, aged 70-79 years, enrolled in the Health, Aging, and Body Composition study. Multivariate logistic regression analyses were conducted with potential errors on reported total energy intake on the Food Frequency Questionnaire (FFQ) as the outcome variable and with cognitive ability, measured by the Modified Mini Mental State Exam (3MS) as the primary independent variable. The regression model controlled for site, race, gender, age, body size, and physical activity. Separate models were fit using 3MS as a continuous variable and for multiple 3MS cutpoints. All models revealed similar findings. RESULTS: Cognitive ability was inversely associated with potential errors in reporting total energy intake, whereby a five-point increase in 3MS scores was associated with a 14% decreased likelihood of reporting errors (Odds Ratio=0.86, 95% Confidence Interval: 0.77, 0.95). Additionally, compared to White women, White men were 2 times more likely, and Black women and Black men were 3 times more likely, to have errors in reporting total energy intake. CONCLUSION: This study provides evidence that for older adults, lower cognition scores are associated with increased potential errors in reporting total energy intake. APPLICATIONS: Dietary reporting from older adults may be inaccurate due to cognitive deficits. A brief assessment of cognitive function may assist clinicians in dietary evaluations and recommendation and may benefit studies using FFQ data where the measure of cognitive function could be utilized to stratify data analyses and conduct sensitivity analyses.


Assuntos
Transtornos Cognitivos/complicações , Cognição/fisiologia , Ingestão de Energia/fisiologia , Autorrevelação , Inquéritos e Questionários/normas , Idoso , População Negra/estatística & dados numéricos , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Escalas de Graduação Psiquiátrica , Psicometria , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais , População Branca/estatística & dados numéricos
11.
Vet Rec ; 158(17): 585-8, 2006 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-16648438

RESUMO

A total of 417 pigs with an estimated average liveweight of 91 kg were transported to slaughter in three journeys, carried out in late June, each consisting of a three-hour drive followed by a one-hour holding period at the slaughter plant before they were unloaded. The pigs were accommodated on the lower two decks of a three-deck articulated lorry, each deck having five equal-sized pens; half were kept in naturally ventilated pens and half in pens with fan-assisted ventilation. The pigs' body temperature was recorded as the temperature of the blood lost at exsanguination, and as the temperature of the inner surface of the ear measured by thermal imaging. The pigs carried on the upper deck were hotter than those carried on the lower deck, and the pigs carried at the front of the vehicle were hotter than those at the back. There were small differences between the temperatures of the pigs in the different pens, but overall the temperatures of the pigs kept in pens with fan-assisted ventilation were no lower than those of the pigs kept in pens with natural ventilation. The higher temperature of the pigs transported in the front of the vehicle was associated with significantly higher serum concentrations of cortisol and activities of creatine kinase, and a tendency to higher albumin concentrations and osmolality, suggesting that they may have been exposed to more physical and psychological stress, and were possibly slightly more dehydrated, than the pigs in the rearmost pens. The type of ventilation had no effect on the blood composition of the pigs.


Assuntos
Bem-Estar do Animal , Estresse Fisiológico/veterinária , Suínos , Meios de Transporte/métodos , Animais , Temperatura Corporal/fisiologia , Creatina Quinase/metabolismo , Desenho de Equipamento/veterinária , Abrigo para Animais/normas , Hidrocortisona/sangue , Estresse Fisiológico/sangue , Estresse Fisiológico/metabolismo , Temperatura , Fatores de Tempo , Meios de Transporte/instrumentação , Reino Unido
12.
Br Poult Sci ; 47(2): 135-46, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16641024

RESUMO

Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay.


Assuntos
Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Constituição Corporal/fisiologia , Galinhas/fisiologia , Abrigo para Animais , Animais , Aglomeração , Plumas , Feminino , Abrigo para Animais/normas , Mortalidade , Tamanho do Órgão , Oviposição/fisiologia , Densidade Demográfica , Dinâmica Populacional , Distribuição Aleatória
13.
Clin Exp Allergy ; 36(4): 543-53, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16630161

RESUMO

BACKGROUND: Of the numerous adhesion molecules expressed by eosinophils, the alpha4-integrin has been identified as critically involved in eosinophil trafficking in the lung. Most studies have focused on the role of the alpha4beta1-adhesion complex, but eosinophils also express the alpha4beta7-integrin complex. OBJECTIVE: To investigate the role of alpha4beta7, by assessing its membrane expression on eosinophils from different compartments using allergen-challenged mice and IL-4/IL-5 bi-transgenic mice. In addition, we aim to determine the impact of beta7-integrin deficiency on eosinophil recruitment to the lungs and intestine in specific experimental allergic models. RESULTS: Evaluation of alpha4beta7 expression on bronchoalveolar lavage fluid (BALF) and lung tissue eosinophils revealed a down-regulation of this integrin as eosinophils migrate through the lungs. Indeed eosinophils isolated from the BALF and lung of allergic mice had low expression of the alpha4beta7-complex. While expression of the alpha4-chain remained unchanged, a significant decrease in beta7-surface expression was observed. Intestinal eosinophils, isolated from Peyer's patches, also displayed a down-regulation of the alpha4beta7-integrin, albeit only modest. In contrast, circulating eosinophils, isolated from the blood and spleen, expressed high levels of the alpha4beta7-integrin. However, eosinophil trafficking into the lungs of beta7-integrin-deficient mice was not significantly impaired in response to respiratory allergen challenges. In contrast, beta7-deficient mice had impaired eosinophil recruitment to the intestine. CONCLUSION: Taken together, these results identify differential expression of the alpha4beta7-integrin on eosinophils and its critical role in regulating eosinophil responses in the intestine.


Assuntos
Asma/imunologia , Eosinófilos/imunologia , Integrinas/análise , Intestinos/citologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Movimento Celular/imunologia , Modelos Animais de Doenças , Regulação para Baixo/imunologia , Integrina alfa4/imunologia , Cadeias beta de Integrinas/imunologia , Interleucina-4/imunologia , Interleucina-5/imunologia , Intestinos/imunologia , Pulmão/citologia , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Nódulos Linfáticos Agregados/imunologia , Baço/citologia , Baço/imunologia
14.
Vet Rec ; 158(10): 331-4, 2006 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-16531581

RESUMO

Measurements on 28 pens of pigs containing 384 animals to be slaughtered at a commercial abattoir showed that the mean ear temperatures of the pigs in each pen, measured with a thermal imaging camera, were significantly correlated (r=0.71, P<0.001) with the mean temperature of the blood the pigs lost at exsanguination. In measurements on 220 pigs in 16 of the 28 pens, the mean activity of serum creatine kinase was positively correlated with the mean ear temperature (r=0.55, P<0.05) and the mean concentration of serum cortisol was positively correlated with the mean blood temperature (r=0.50, P<0.05), suggesting that the hotter pigs were suffering from a higher level of stress.


Assuntos
Matadouros , Temperatura Corporal/fisiologia , Suínos/sangue , Termografia/veterinária , Animais , Biomarcadores/sangue , Creatina Quinase/sangue , Hidrocortisona/sangue , Estresse Fisiológico/sangue , Estresse Fisiológico/veterinária , Doenças dos Suínos/sangue , Termografia/métodos
16.
Aging Ment Health ; 6(1): 72-6, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11827625

RESUMO

The shortage of geriatric specialists in the US may require that primary care physicians (PCPs) receive more education on diagnosing and managing dementia since the number of older Americans with dementia will increase from about five million in 2010 to up to 14 million in 2050. Thus, we administered a brief, anonymous questionnaire to determine PCPs' diagnostic, referral, and management practices to a convenience sample of 142 PCPs in Arkansas. We reworded a Scottish survey to conform to terminology used in the US and added items on referral practices. The PCPs who reported difficulty establishing the diagnosis of dementia had more difficulty telling the diagnosis (O.R = 3.59, p < 0.004). The PCPs were less likely (p < 0.001) to tell the patient if they suspected dementia (73%) than if they were sure the patient had dementia (88%). In both cases, they were more likely to tell the family (92% & 100%, respectively), although this difference was not statistically significant. The PCPs discussed disease progression and driving risks with patients and families, but few referred them to social workers or community agencies. Findings support training PCPs in the diagnosis and management of persons with dementia and providing tools to improve care.


Assuntos
Demência/diagnóstico , Médicos de Família , Padrões de Prática Médica , Arkansas , Coleta de Dados , Feminino , Humanos , Masculino
17.
Womens Health Issues ; 11(6): 494-502, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11704470

RESUMO

This study examined risk factors for functional limitations in a community-based sample of 16,065 women from 5 ethnic groups, aged 40-55 years, enrolled in the Study of Women's Health Across the Nation. Almost 20% of this sample reported physical-functioning limitations. Functional limitations were associated with numerous disease conditions, including high blood pressure, diabetes, heart attack or angina, arthritis, osteoporosis, and cancer, and with several behavioral and environmental risk factors, including body mass index, difficulty paying for basics, and high levels of perceived stress. Consistent with findings in older women, this study shows that in addition to health conditions, potentially modifiable risk factors including high body mass index, difficulty paying for basics, and high levels of stress are associated with physical-functioning limitations of women at midlife.


Assuntos
Atividades Cotidianas/classificação , Doença Crônica/epidemiologia , Inquéritos Epidemiológicos , Saúde da Mulher , Adulto , Índice de Massa Corporal , Estudos Transversais , Etnicidade/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Estados Unidos/epidemiologia
18.
J Allergy Clin Immunol ; 108(4): 594-601, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11590387

RESUMO

BACKGROUND: IL-13 induces several characteristic features of asthma, including airway eosinophilia, airway hyperresponsiveness, and mucus overproduction; however, the mechanisms involved are largely unknown. OBJECTIVE: We hypothesized that IL-13-induced inflammatory changes in the lung were dependent in part on IL-5 and eotaxin, two eosinophil-selective cytokines. METHODS: Recombinant murine IL-13 was repeatedly administered to the lung by intranasal delivery until the characteristic features of asthma developed. To analyze the role of IL-5 and eotaxin, we subjected eotaxin gene-targeted, IL-5 gene-targeted, eotaxin/IL-5-double-deficient, IL-5 transgenic, and wild-type mice of the Balb/C background to the experimental regime. RESULTS: The induction of IL-13-mediated airway eosinophilia was found to occur independently of eosinophilia in the blood or bone marrow, indicating that IL-13-induced airway inflammation is primarily mediated by local effects of IL-13 in the lung. Eosinophil recruitment into both the lung tissue and bronchoalveolar lavage fluid was markedly attenuated in IL-5-deficient mice in comparison with wild-type controls. Accordingly, IL-13 delivery to IL-5 transgenic mice resulted in a large increase in airway eosinophils in comparison with wild-type mice. Interestingly, IL-13-induced eosinophilia in the bronchoalveolar lavage fluid of eotaxin-deficient mice was not impaired; however, these same mice failed to mount a significant tissue eosinophilia in response to IL-13. Finally, IL-13-induced mucus production was not affected by the presence of IL-5 or eotaxin, suggesting that IL-13-induced mucus secretion is mechanistically dissociated from airway eosinophilia. CONCLUSION: Selective components of the IL-13-induced asthma phenotype--airway eosinophilia but not mucus secretion--are differentially regulated by IL-5 and eotaxin. IL-5 is required for IL-13 to induce eosinophilia throughout the lung, whereas eotaxin regulates the distribution of airway eosinophils.


Assuntos
Quimiocinas CC , Citocinas/metabolismo , Interleucina-13/farmacologia , Interleucina-5/metabolismo , Eosinofilia Pulmonar/induzido quimicamente , Animais , Quimiocina CCL11 , Quimiotaxia de Leucócito , Citocinas/genética , Feminino , Interleucina-5/genética , Pulmão/patologia , Masculino , Camundongos , Camundongos Transgênicos , Muco/metabolismo
19.
Nucleosides Nucleotides Nucleic Acids ; 20(3): 169-83, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11393395

RESUMO

A high-resolution NMR study of the solution structure of the calcium release agent cADPR has been performed. Pseudorotationals analysis reveals that in solution both sugar rings in cADPR adopt predominantly (approximately 75%) South conformations, with the A and N rings adopting approximately 2T3 (C2'-endo(major)-C3'-exo(minor) and 4(3)T (C3'-exo-C4'-endo) conformations, respectively. The backbone torsion angles beta and gamma have also been determined. While the minor North conformers were not observed in the crystal structure of cADPR, the solution values of the major South conformers compare well to those found in crystal structure.


Assuntos
Adenosina Difosfato Ribose/análogos & derivados , Adenosina Difosfato Ribose/química , Espectroscopia de Ressonância Magnética/métodos , ADP-Ribose Cíclica , Estrutura Molecular , Soluções/química
20.
Appl Anim Behav Sci ; 73(2): 141-155, 2001 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-11358611

RESUMO

It has been proposed that chicks acquire substrate preferences during an early 'sensitive' period. If a suitable substrate is absent during this period birds may develop alternative preferences for pecking at feathers. The aim of this study was to examine whether early substrate exposure has durable effects on the subsequent behaviour of adult hens. The effects of duration of substrate exposure, substrate change, age at exposure and time since exposure on adult bird behaviour were examined. From days 1 to 210, 144 laying strain birds were housed in pairs in pens with wire floors. The floors were replaced with solid floors covered in wood shavings at different ages and for different durations by allocation to 1 of 12 treatments. Adult birds that had never experienced shavings performed significantly more feather pecking than birds in any other treatment group. Thus, exposure to shavings, even for the minimum exposure duration of 10 days, was protective. However, current substrate was of great importance and adult birds housed on shavings performed significantly more ground pecking and less feather pecking than birds on wire, regardless of previous experience. From day 211 all hens were given shavings or straw, presented alternately for five 24h sessions over 10 consecutive days. Birds foraged on both substrates and their foraging behaviour was not influenced by previous experience. Dustbathing occurred primarily on shavings and was significantly influenced by the age at which birds had previously been exposed to shavings. Dustbathing on shavings was fairly constant throughout the 10-day test period in all groups, suggesting that relatively stable preferences had developed. A secondary 'sensitive period' for the formation of adult dustbathing substrate preference may have superseded the early 'imprinting' process. However, adult behaviour was generally flexible and strongly influenced by current substrate.

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