Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 187
Filtrar
1.
Public Health ; 176: 68-76, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30739731

RESUMO

OBJECTIVES: The purpose of the article was to explore the application and interpretation of indigenous stories introduced in 2015-2017 in relation to the identity and leadership (well-being elements) of players and coaches of a men's provincial rugby team in Aotearoa/New Zealand (NZ). STUDY DESIGN: The study utilised a Kaupapa Maori case study approach and indigenous forms of storytelling (purakau, whakatauki) to encourage participants to share their narratives and experiences of how the inclusion of Maori knowledge in a team context influenced their sense of identity and leadership and thus well-being on and off the field. METHODS: Semi-structured, one-on-one, interviews alongside focus group discussions generated the data (narratives) collected. Data were thematically analysed, utilising aspects of an indigenous model of Health Promotion known as Te Pae Mahutonga. Specifically, the cultural identity affirmation (Mauri Ora) and leadership (Nga Manukura) elements were illustrated as these were applicable to high performance sport contexts. RESULTS: Analysis revealed that the team narrative, values and expectations were enhanced by embracing Maori stories (purakau) and symbols. In particular, this enhanced the cultural identity, sense of belonging, leadership and well-being of a number of team members on and off-field. Neither the players nor coaches disclosed any negative impacts to their well-being from incorporating indigenous storytelling (purakau, whakatauki) into their team building practices and culture. CONCLUSIONS: Sport-related research and practices that are informed by indigenous knowledge and values can benefit the well-being of indigenous people (in this case Maori), collectives (rugby team) and individuals (researchers, players and coaches). Further research exploring how indigenous knowledge is integrated into sport-related contexts is needed to understand whether the well-being of a wider range of teams and individuals (women, non-indigenous) may benefit from the inclusion of indigenous knowledge, values and practices.


Assuntos
Atletas/psicologia , Promoção da Saúde/métodos , Liderança , Saúde Mental/etnologia , Narração , Grupos Populacionais/psicologia , Identificação Social , Atletas/estatística & dados numéricos , Características Culturais , Grupos Focais , Futebol Americano , Humanos , Masculino , Nova Zelândia , Grupos Populacionais/estatística & dados numéricos , Pesquisa Qualitativa
2.
J Clin Endocrinol Metab ; 99(4): 1245-52, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24512493

RESUMO

BACKGROUND: Poorly differentiated thyroid cancer (PDTC) accounts for only 1-15% of all thyroid cancers. Our objective is to report outcomes in a large series of patients with PDTC treated at a single tertiary care cancer center. METHODS: A total of 91 patients with primary PDTC were treated by initial surgery with or without adjuvant therapy at Memorial Sloan-Kettering Cancer Center from 1986 to 2009. Outcomes were calculated by the Kaplan-Meier method. Clinicopathological characteristics were compared for PDTC patients who died of disease to those who did not by the χ(2) test. Factors predictive of disease-specific survival (DSS) were calculated by univariate and multivariate analysis using the log rank and Cox proportional hazards method, respectively. RESULTS: With a median follow-up of 50 months, the 5-year overall survival and DSS were 62 and 66%, respectively. The 5-year locoregional and distant control were 81 and 59%, respectively. Of 27 disease-specific deaths, 23 (85%) were due to distant disease. Age ≥ 45 years, pathological tumor size >4 cm, extrathyroidal extension, higher pathological T stage, positive margins, and distant metastases (M1) were predictive of worse DSS on univariate analysis. Multivariate analysis showed that only pT4a stage and M1 were independent predictors of worse DSS. CONCLUSIONS: With appropriate surgery and adjuvant therapy, excellent locoregional control can be achieved in PDTC. Disease-specific deaths occurred due to distant metastases and rarely due to uncontrolled locoregional recurrence in this series.


Assuntos
Carcinoma/patologia , Carcinoma/terapia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Terapia Combinada/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Neoplasias da Glândula Tireoide/mortalidade , Tireoidectomia/estatística & dados numéricos , Resultado do Tratamento , Adulto Jovem
3.
Ann Surg Oncol ; 21(5): 1665-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554064

RESUMO

BACKGROUND: Anaplastic thyroid carcinoma (ATC) is among the most aggressive solid tumors accounting for 1-5 % of primary thyroid malignancies. In this retrospective review, we aim to evaluate the prognostic factors, treatment approaches, and outcomes of patients with ATC treated at a single institution. MATERIALS AND METHODS: We retrospectively identified 95 patients with ATC from an institutional database between 1985 and 2010. A total of 83 patients with sufficient records were included in this study. Patient, tumor, and treatment characteristics were recorded. Disease-specific survival (DSS) was determined by the Kaplan-Meier method, and factors predictive of outcome were determined by univariate and multivariate analysis. RESULTS: Of the 83 patients, 41 were male and 42 were female. The median age at presentation was 60 years (range 28-89 years) with a median survival of 8 months. The 1- and 2-year DSS were 33 and 23 %, respectively. On univariate analysis, age less than 60 years, clinically N0 neck, absence of clinical extrathyroidal extension (cETE), gross total resection, and multimodality treatment were statistically significant predictors of improved survival. On multivariate analysis, absence of cETE, multimodality therapy, and gross total resection were predictors of improved outcome. CONCLUSIONS: In patients with locoregional limited disease, multimodality treatment with gross total surgical resection and postoperative radiotherapy with or without chemotherapy offers the best local control and DSS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Radioterapia , Carcinoma Anaplásico da Tireoide/terapia , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Carcinoma Anaplásico da Tireoide/mortalidade , Carcinoma Anaplásico da Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia
4.
Child Care Health Dev ; 40(3): 398-404, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23594151

RESUMO

BACKGROUND: Interventions for childhood overweight and obesity that target parents as the agents of change by increasing parent self-efficacy for facilitating their child's healthy weight behaviours require a reliable and valid tool to measure parent self-efficacy before and after interventions. Nelson and Davis developed the Parent Efficacy for Child Healthy Weight Behaviour (PECHWB) scale with good preliminary evidence of reliability and validity. The aim of this research was to provide further psychometric evidence from an independent Australian sample. METHODS: Data were provided by a convenience sample of 261 primary caregivers of children aged 4-17 years via an online survey. PECHWB scores were correlated with scores on other self-report measures of parenting efficacy and 2- to 4-week test-retest reliability of the PECHWB was assessed. RESULTS: The results of the study confirmed the four-factor structure of the PECHWB (Fat and Sugar, Sedentary Behaviours, Physical Activity, and Fruit and Vegetables) and provided strong evidence of internal consistency and test-retest reliability, as well as good evidence of convergent validity. CONCLUSION: Future research should investigate the properties of the PECHWB in a sample of parents of overweight or obese children, including measures of child weight and actual child healthy weight behaviours to provide evidence of the concurrent and predictive validity of PECHWB scores.


Assuntos
Comportamento Infantil , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Poder Familiar , Adolescente , Peso Corporal , Criança , Pré-Escolar , Estudos Transversais , Feminino , Frutas , Humanos , Estilo de Vida , Masculino , Atividade Motora , Obesidade/prevenção & controle , Psicometria , Reprodutibilidade dos Testes , Autoeficácia , Verduras
6.
Acta Physiol (Oxf) ; 197(4): 289-96, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19645752

RESUMO

AIM: Obesity is a major contributor to the global burden of disease and is closely associated with the development of type 2 diabetes and cardiovascular diseases. This study tested the hypothesis that mitochondrial respiratory capacity of the pre-diabetic heart is decreased leading to impaired contractile function and tolerance to ischaemia/reperfusion. METHODS: Eight-week-old male Wistar rats were fed a high caloric diet for 16 weeks after which anthropometric, metabolic, cardiac and mitochondrial parameters were evaluated vs. age-matched lean controls. Cardiac function (working heart perfusions) and mitochondrial respiratory capacity were assessed at baseline and in response to acute oxygen deprivation. RESULTS: Rats fed the high caloric diet exhibited increased body weight and visceral fat vs. the control group. Heart weights of obese rats were also increased. Triglyceride, fasting plasma insulin and free fatty acid levels were elevated, while high-density lipoprotein cholesterol levels were reduced in the obese group. Contractile function was attenuated at baseline and further decreased after subjecting hearts to ischaemia-reperfusion. Myocardial infarct sizes were increased while ADP phosphorylation rates were diminished in obese rats. However, no differences were found for mtDNA levels and the degree of oxidative stress-induced damage. CONCLUSIONS: These data show that decreased mitochondrial bioenergetic capacity in pre-diabetic rat hearts may impair respiratory capacity and reduce basal contractile function and tolerance to acute oxygen deprivation.


Assuntos
Respiração Celular/fisiologia , Hipóxia/metabolismo , Mitocôndrias/metabolismo , Contração Miocárdica/fisiologia , Estado Pré-Diabético/fisiopatologia , Animais , Peso Corporal , Dieta , Modelos Animais de Doenças , Masculino , Miocárdio/citologia , Miocárdio/metabolismo , Miocárdio/patologia , Obesidade/complicações , Obesidade/fisiopatologia , Consumo de Oxigênio/fisiologia , Estado Pré-Diabético/etiologia , Ratos , Ratos Wistar
7.
Mitochondrion ; 8(5-6): 389-95, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18824141

RESUMO

The transference of the nutritional function from the VYS to the chorioallantoic placenta during middle pregnancy is a key event for the activation of embryo oxidative metabolism. However, the metabolic adaptations occurring in these tissues during this critical period have not been studied to date. Herein, we investigate the VYS and placenta mitochondrial adaptations throughout gestational days 11, 12 and 13. The results reflect that, during the placentation period, mitochondrial proliferation predominates over differentiation in placenta. Besides, VYS development and mitochondriogenesis show a slowdown despite maintaining the mitochondrial OXPHOS capacities, hence becoming a supporting tissue until the placenta functions are completely available.


Assuntos
Mitocôndrias/fisiologia , Placenta/ultraestrutura , Placentação , Saco Vitelino/ultraestrutura , Animais , Ciclo-Oxigenase 1/análise , DNA Mitocondrial/análise , Feminino , Proteínas Mitocondriais/análise , Tamanho do Órgão , Fosforilação Oxidativa , Gravidez , Ratos , Ratos Wistar
8.
Reproduction ; 134(1): 147-54, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17641096

RESUMO

Mitochondrial biogenesis and function are essential for proper embryo development; however, these processes have not been further studied during the placentation period, when important oxidative metabolism activation is taking place. Thus, the aim of the present study was to investigate the oxidative phosphorylation system (OXPHOS) enzymatic activities as well as the expression of genes involved in the coordinated regulation of both mitochondrial and nuclear genomes (peroxisome proliferator-activated receptor-gamma coactivator-1alpha, nuclear respiratory factors 1 and 2, mitochondrial single-strand DNA-binding protein, mitochondrial transcription factor A), and mitochondrial function (cytochrome c oxidase subunit IV, cytochrome c oxidase subunit I and beta-ATP phosphohydrolase) in rat embryo throughout the placentation period (gestational days 11, 12 and 13). Our results reflect that embryo mitochondria were enhancing their OXPHOS potential capacities, pointing out that embryo mitochondria become more differentiated during the placentation period. Besides, the current findings show that the mRNAs of the nuclear genes involved in mitochondrial biogenesis were downregulated, whereas their protein content together with the mitochondrial DNA expression were upregulated throughout the period studied. These data indicate that the molecular regulation of the mitochondrial differentiation process during placentation involves a post-transcriptional activation of the nuclear-encoded genes that would lead to an increase in both the nuclear- and mitochondrial-encoded proteins responsible for the mitochondrial biogenic process. As a result, embryo mitochondria would reach a more differentiated stage with a more efficient oxidative metabolism that would facilitate the important embryo growth during the second half of the pregnancy.


Assuntos
Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Mitocôndrias/fisiologia , Placentação/fisiologia , Animais , Western Blotting , Diferenciação Celular , DNA Mitocondrial/análise , Embrião de Mamíferos/ultraestrutura , Feminino , Mitocôndrias/ultraestrutura , Proteínas Nucleares/análise , Proteínas Nucleares/genética , Fosforilação Oxidativa , Gravidez , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
9.
Am J Physiol Cell Physiol ; 293(4): C1302-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17652427

RESUMO

Caloric restriction (CR) without malnutrition has been shown to increase maximal life span and delay the rate of aging in a wide range of species. It has been proposed that reduction in energy expenditure and oxidative damage may explain the life-extending effect of CR. Sex-related differences also have been shown to influence longevity and energy expenditure in many mammalian species. The aim of the present study was to determine the sex-related differences in rat liver mitochondrial machinery, bioenergetics, and oxidative balance in response to short-term CR. Mitochondria were isolated from 6-mo-old male and female Wistar rats fed ad libitum or subjected to 40% CR for 3 mo. Mitochondrial O(2) consumption, activities of the oxidative phosphorylation system (complexes I, III, IV, and V), antioxidative activities [MnSOD, glutathione peroxidase (GPx)], mitochondrial DNA and protein content, mitochondrial H(2)O(2) production, and markers of oxidative damage, as well as cytochrome C oxidase and mitochondrial transcription factor A levels, were measured. Female rats showed a higher oxidative capacity and GPx activity than males. This sexual dimorphism was not modified by CR. Restricted rats showed slightly increased oxygen consumption, complex III activity, and GPx antioxidant activity together with lower levels of oxidative damage. In conclusion, the sexual dimorphism in liver mitochondrial oxidative capacity was unaffected by CR, with females showing higher mitochondrial functionality and ROS protection than males.


Assuntos
Restrição Calórica , Mitocôndrias Hepáticas/metabolismo , Fosforilação Oxidativa , Animais , Peso Corporal/fisiologia , DNA Mitocondrial/análise , Complexo I de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/análise , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Fígado/anatomia & histologia , Fígado/química , Fígado/metabolismo , Masculino , Mitocôndrias Hepáticas/química , Proteínas Mitocondriais/análise , Proteínas Mitocondriais/metabolismo , Tamanho do Órgão/fisiologia , Consumo de Oxigênio/fisiologia , Carbonilação Proteica/fisiologia , Ratos , Ratos Wistar , Fatores Sexuais , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Transcrição/análise , Fatores de Transcrição/metabolismo
10.
Am J Physiol Endocrinol Metab ; 293(3): E636-44, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17609253

RESUMO

Mitochondria are cellular organelles that have been reported to be altered in diabetes, being closely related to its associated complications. Moreover, mitochondrial biogenesis and function are essential for proper embryo development throughout the placentation period, occurring during organogenesis, when a great rate of congenital malformations have been associated with diabetic pregnancy. Thus, the aim of the current work was to investigate the effect of the diabetic environment on mitochondrial function and biogenesis during the placentation period. For this purpose, we studied the oxidative phosphorylation system (OXPHOS) enzymatic activities as well as the expression of genes involved in the coordinated regulation of both mitochondrial and nuclear genome (PGC-1alpha, NRF-1, NRF-2alpha, mtSSB, and TFAM) and mitochondrial function (COX-IV, COX-I, and beta-ATPase) in rat embryos from control and streptozotocin-induced diabetic mothers. Our results reflected that diabetic pregnancy retarded and altered embryo growth. The embryos from diabetic mothers showing normal morphology presented a reduced content of proteins regulated through the PGC-1alpha mitochondriogenic pathway on gestational day 12. This fact was accompanied by several responses that entailed the activation of OXPHOS activities on the same day and the recovery of the content of the studied proteins to control levels on day 13. As a result, the mitochondria of these embryos would reach a situation close to control on day 13 that could allow them to follow the normal mitochondriogenic schedule throughout a gestational period in which the mitochondrial differentiation process is critical. Nevertheless, malformed embryos from diabetic mothers seemed to show a lower adaptation capability, which could exacerbate their maldevelopment.


Assuntos
Desenvolvimento Embrionário , Mitocôndrias/ultraestrutura , Placentação , Gravidez em Diabéticas/patologia , Gravidez em Diabéticas/fisiopatologia , Animais , Diferenciação Celular , Feminino , Gravidez , Ratos , Ratos Wistar
12.
Am J Physiol Endocrinol Metab ; 289(1): E15-22, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15701677

RESUMO

Sex-related differences in energy balance were studied in young Wistar rats fed standard chow pellets either ad libitum or in restricted amounts (60% of ad libitum intake) for 100 days. Caloric intake, indirect calorimetry, organ and adipose tissue weights, energy efficiency, liver mitochondrial respiration rate, and brown adipose tissue (BAT) uncoupling protein-1 (UCP1) content were measured. Ad libitum-fed females showed greater oxygen consumption (Vo(2)) and carbon dioxide production (Vco(2)) and lower energy efficiency than males. Caloric restriction induced a chronic drop of Vo(2) and Vco(2) in females but not in males over the period studied. Restricted females showed a better conservation of metabolic active organ mass and a greater decrease in adipose depots than restricted males. Moreover, changes of BAT size and UCP1 content suggest that BAT may be the main cause responsible for sex differences in the response of energy balance to caloric restriction. In conclusion, our results indicate that females under caloric restriction conditions deactivate facultative thermogenesis to a greater degree than males. This ability may have obvious advantages for female survival and therefore the survival of the species when food is limiting.


Assuntos
Adaptação Fisiológica/fisiologia , Tecido Adiposo Marrom/fisiologia , Peso Corporal/fisiologia , Restrição Calórica/métodos , Metabolismo Energético/fisiologia , Consumo de Oxigênio/fisiologia , Termogênese/fisiologia , Animais , Feminino , Masculino , Ratos , Ratos Wistar , Fatores Sexuais
14.
Cell Mol Life Sci ; 59(12): 2199-209, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12568346

RESUMO

To establish the role of mitochondrial subpopulations in the mitochondrial maturation process, we studied morphological and functional changes in the mitochondria of different mammalian conceptus tissues during the organogenic and the placentation processes. Mitochondrial subpopulations of three different conceptus tissues, embryo and visceral yolk sac placenta on gestational days 11, 12 and 13 and placenta on days 12 and 13, were examined morphologically by transmission electron microscopy. Cytochrome oxidase activity and protein levels were also measured in each mitochondrial subpopulation. The results indicate two different mitochondrial subpopulation profiles: a homogeneous one, which corresponds to immature mitochondria, and a heterogeneous one, which represents the mature mitochondria. The three tissues studied show different morphologic and metabolic patterns of mitochondrial maturation during the placentation process, rendering them suitable as experimental models to establish the possible relationship between mitochondrial maturation and the mitochondrial subpopulations.


Assuntos
Embrião de Mamíferos/fisiologia , Embrião de Mamíferos/ultraestrutura , Mitocôndrias/fisiologia , Placentação/fisiologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Idade Gestacional , Mitocôndrias/ultraestrutura , Placenta/metabolismo , Placenta/ultraestrutura , Gravidez , Ratos , Ratos Wistar , Saco Vitelino/metabolismo , Saco Vitelino/ultraestrutura
15.
Artigo em Inglês | MEDLINE | ID: mdl-11241880

RESUMO

In recent years there have been a number of advances in understanding of predisposing and protective factors in the development of cerebral palsy in infants. Multiple gestation births, maternal infection, and maternal and fetal thrombophilic conditions all predispose to the development of CP in the infant. Opportunities for prevention of CP may develop from an improved understanding of these factors and their mechanisms of operation. Similar progress has been made in the evaluation of treatments for CP and the effects of these treatments on the individual's impairment, function, and disability. Selective posterior rhizotomy and Botulinum toxin A are now widely used in the treatment of spasticity. The challenge remains to determine how effectively these promising interventions can alter long-term function and quality of life outcomes in children and adults with CP.


Assuntos
Paralisia Cerebral/terapia , Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/etiologia , Paralisia Cerebral/prevenção & controle , Ensaios Clínicos como Assunto , Feminino , Humanos , Recém-Nascido , Sulfato de Magnésio/administração & dosagem , Masculino , Espasticidade Muscular/etiologia , Espasticidade Muscular/prevenção & controle , Espasticidade Muscular/terapia , Gravidez , Gravidez Múltipla , Rizotomia , Fatores de Risco , Resultado do Tratamento
16.
Pediatr Neurol ; 23(3): 208-15, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11033282

RESUMO

The Cognitive Adaptive Test/Clinical Linguistic and Auditory Milestone Scale (CAT/CLAMS), a neurodevelopmental tool for the cognitive assessment of infants and toddlers, correlates well with the Bayley Scales of Infant Development. In 1993 the Bayley Scales were revised and the second edition published (BSID-II). This study was designed to determine how well the CAT/CLAMS correlates with the BSID-II and its utility in identifying mild and severe cognitive impairment. Sixty-eight infants and toddlers (age range = 14-48 months), referred for suspected developmental delays, were administered the CAT/CLAMS and BSID-II and the results compared. The correlation between the two instruments was strong (r = 0.89, P<0.0001). The CAT/CLAMS was sensitive (81%) and specific (85%) for detecting overall cognitive impairment (BSID-II less than 70) and was even more sensitive (100%) and specific (96%) in detecting severe cognitive impairment (BSID-II less than 50). The physician using the CAT/CLAMS formulated a clinical impression of cognitive impairment that was sensitive (95%) and specific (84%) compared with formal psychologic testing. The CAT/CLAMS correlates well with the BSID-II. It is useful for detecting and quantifying mild and severe cognitive impairment. It permits the physician to formulate an accurate clinical impression of cognitive impairment consistent with possible mental retardation.


Assuntos
Transtornos Cognitivos/diagnóstico , Deficiências do Desenvolvimento/diagnóstico , Testes Neuropsicológicos/estatística & dados numéricos , Pré-Escolar , Transtornos Cognitivos/psicologia , Deficiências do Desenvolvimento/psicologia , Intervenção Educacional Precoce , Feminino , Humanos , Lactente , Masculino , Psicometria , Reprodutibilidade dos Testes
17.
J Neurochem ; 75(5): 1834-44, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11032872

RESUMO

The targeting of mRNAs to specific subcellular locations is believed to facilitate the rapid and selective incorporation of their protein products into complexes that may include membrane organelles. In oligodendrocytes, mRNAs that encode myelin basic protein (MBP) and select myelin-associated oligodendrocytic basic proteins (MOBPs) locate in myelin sheath assembly sites (MSAS). To identify additional mRNAs located in MSAS, we used a combination of subcellular fractionation and suppression subtractive hybridization. More than 50% of the 1,080 cDNAs that were analyzed were derived from MBP or MOBP mRNAs, confirming that the method selected mRNAs enriched in MSAS. Of 90 other cDNAs identified, most represent one or more mRNAs enriched in rat brain myelin. Five cDNAs, which encode known proteins, were characterized for mRNA size(s), enrichment in myelin, and tissue and developmental expression patterns. Two of these, peptidylarginine deiminase and ferritin heavy chain, have recognized roles in myelination. The corresponding mRNAs were of different sizes than the previously identified mRNA, and they had tissue and development expression patterns that were indistinguishable from those of MBP mRNA. Three other cDNAs recognize mRNAs whose proteins (SH3p13, KIF1A, and dynein light intermediate chain) are involved in membrane biogenesis. Although enriched in myelin, the tissue and developmental distribution patterns of these mRNAs differed from those of MBP mRNA. Six other cDNAs, which did not share significant sequence homology to known mRNAs, were also examined. The corresponding mRNAs were highly enriched in myelin, and four had tissue and developmental distribution patterns indistinguishable from those of MBP mRNA. These studies demonstrate that MSAS contain a diverse population of mRNAs, whose locally synthesized proteins are placed to contribute to myelin sheath assembly and maintenance. Characterization of these mRNAs and proteins will help provide a comprehensive picture of myelin sheath assembly.


Assuntos
Proteínas de Drosophila , Bainha de Mielina/química , RNA Mensageiro/análise , Animais , Transporte Biológico , Northern Blotting , Encéfalo/metabolismo , Química Encefálica , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Dineínas , Etiquetas de Sequências Expressas , Ferritinas/genética , Ferritinas/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Cinesinas/genética , Cinesinas/metabolismo , Dados de Sequência Molecular , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/metabolismo , Proteínas da Mielina , Bainha de Mielina/genética , Bainha de Mielina/metabolismo , Glicoproteína Associada a Mielina/genética , Glicoproteína Associada a Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos , Homologia de Sequência do Ácido Nucleico , Frações Subcelulares/química
18.
Am J Respir Crit Care Med ; 161(1): 32-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10619794

RESUMO

We have previously shown that the activity of cytochrome oxidase (CytOx) in skeletal muscle of patients with chronic obstructive pulmonary disease (COPD) was higher than in healthy control subjects. The mechanisms and implications of this observation were unclear. In particular, it was not known if this abnormality can occur also in: (1) cell types other than muscle cells, and (2) other chronic inflammatory diseases. To obtain further insight into these questions, we measured the activity of CytOx in circulating lymphocytes in patients with stable COPD (n = 17), bronchial asthma (n = 6), or chronic arthritis (n = 5), and in healthy control subjects (n = 8). We found that, compared with healthy subjects (280 +/- 117 nKat/microg protein), patients with COPD showed increased CytOx activity (430 +/- 150 nKat/microg protein, p = 0.01) in lymphocytes. Further, this activity was negatively related to the degree of airflow obstruction present in these patients (r = -0.53, p < 0.05). We also found that the activity of CytOx in circulating lymphocytes was higher than normal in patients with chronic arthritis (411 +/- 130 nKat/microg protein, p < 0.05) and, particularly, in patients with bronchial asthma (1,667 +/- 1,027 nKat/microg protein, p < 0.001). These results show that the increased CytOx activity previously reported in skeletal muscle of patients with COPD is also detected in other cell types (such as circulating lymphocytes) and in other chronic inflammatory diseases (such as bronchial asthma and chronic arthritis). The mechanisms and implications of these findings deserve further investigation.


Assuntos
Artrite/sangue , Asma/sangue , Complexo IV da Cadeia de Transporte de Elétrons/sangue , Pneumopatias Obstrutivas/sangue , Linfócitos/enzimologia , Artrite/fisiopatologia , Asma/fisiopatologia , Biomarcadores/sangue , Doença Crônica , Humanos , Pneumopatias Obstrutivas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Fumar/efeitos adversos
20.
Prostaglandins Other Lipid Mediat ; 55(4): 189-207, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9644111

RESUMO

Agonist-induced intracellular signal transduction often involves activation of protein kinase C by diacylglycerol (DAG) released from membrane phospholipids by phospholipases. Using either DAG kinase or HPLC assays to quantitatively determine DAG mass, we observed a time-dependent increase in DAG accumulation upon incubation of rat C6 glioma cells with 200 nM endothelin-1 (ET-1). Total cell DAG rapidly increased by 25-35% from a basal level of 4.5 +/- 0.3 nmol/mg protein during one min of ET-1 treatment and remained constant or slightly decreased between 1 and 2 min. Thereafter, DAG increased to a maximum (1.6-fold above basal) by 5-10 min. and remained elevated to 30 min. Resolution of DAG molecular species by HPLC after incubation of cells with ET-1 revealed that accumulation of DAG species differed in total cell lysate and subcellular compartments. In plasma membrane, major DAG species increased at 1 min. followed by a decrease at 10 min. whereas in microsomes DAG species did not change at 1 min. and decreased at 10 min. Although phospholipid sources of DAG species were not identified specifically, there was preferential hydrolysis of molecular species of phospholipid for DAG production. We propose that molecular species of DAG produced at the plasma membrane may be transferred to the endoplasmic reticulum so that phospholipid resynthesis can replenish molecular species initially utilized in signal transduction.


Assuntos
Neoplasias Encefálicas/patologia , Membrana Celular/efeitos dos fármacos , Diglicerídeos/metabolismo , Endotelina-1/farmacologia , Glioma/patologia , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Bradicinina/farmacologia , Neoplasias Encefálicas/metabolismo , Cromatografia Líquida de Alta Pressão , Retículo Endoplasmático/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glioma/metabolismo , Humanos , Lipídeos de Membrana/classificação , Camundongos , Microssomos/efeitos dos fármacos , Neurotensina/farmacologia , Fosfolipídeos/classificação , Ratos , Serotonina/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...