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1.
J Cardiovasc Nurs ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38048488

RESUMO

OBJECTIVE: Food insecurity is associated with reduced dietary quality and excess weight gain. However, interventions that are effective for obesity among individuals with food insecurity are unclear. The purpose of this systematic review was to synthesize studies in which authors examined interventions for obesity among adults with food insecurity. METHODS: PubMed, PsycINFO, CINAHL, and EMBASE were searched from inception to October 2022. Studies were included if their authors reported on nonpharmacological and nonsurgical interventions that focused on adults with food insecurity and overweight/obesity and reported weight loss. RESULTS: A total of 1360 titles were reviewed during the electronic search, and only 5 studies met inclusion criteria. There were 2 primary types of interventions that have been tested: first, behavioral weight loss counseling with or without tailoring for individuals with food insecurity and, second, subsidies for food. Findings of the benefits of one type of intervention over another are mixed. CONCLUSIONS: This systematic review highlights that the current evidence for interventions that address food insecurity and obesity is mixed and limited in scope. There is a need for rigorous controlled trials to examine the effectiveness and cost-effectiveness of interventions for weight management among individuals with food insecurity and obesity while considering sustainability.

2.
Medicine (Baltimore) ; 101(43): e31253, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36316873

RESUMO

BACKGROUND: Effective interventions to promote well-being at work are required to reduce the prevalence and consequences of stress and burnout especially during the COVID-19 pandemic. This study determined the effects of mindful coloring on perceived stress levels, mental well-being, burnout, and state and trait mindfulness levels for nurses during COVID-19. METHODS: This was a single-center, two-armed, parallel, superiority, blinded randomized controlled trial. Seventy-seven participants were randomly allocated (by computer-generated sequence) to either mindful coloring (n = 39) or waitlist control groups (n = 38). Twenty-seven nurses in the mindful coloring group and 32 in the control group were included in the full compliance per protocol analysis. The mindful coloring intervention included participants viewing a 3-minutes instructional video and coloring mandalas for at least 5 working days or 100 minutes in total during a 10-day period. Participants in both groups completed the Perceived Stress Scale (total score 0-40), short Warwick-Edinburgh Mental Well-being Scale (total score 7-35), Maslach Burnout Inventory-Human Services Survey for Medical Personnel (3 subscales), Five Facets Mindfulness Questionnaire-Short Form (total score 24-120) and Mindful Attention Awareness Scale-State version (total score 0-30) instruments. The primary outcome was the perceived stress level. RESULTS: Baseline prevalence of moderate to high perceived stress level was high (79.2%). There was a large mindful coloring effect on reducing mean perceived stress levels (Mean difference [MD] in change between groups -3.0, 95% CI: -5.0 to -1.00; Cohen's d = 0.80). Mindful coloring may lead to a small improvement in mental well-being level (P = .08), with an improvement found in the intervention group (MD 0.9, 95% CI 0.0-1.8, P = .04) through enhanced state mindfulness (P < .001). There were no effects on changing burnout subscales or trait mindfulness levels. No adverse reactions were reported. CONCLUSION: Coloring mandalas may be an effective low-cost brief intervention to reduce perceived stress levels through enhancing state mindfulness and it may promote mental well-being. Hospitals may promote or provide mindful coloring as a self-care and stress-relief practice for nurses during their off hours or work breaks.


Assuntos
Esgotamento Profissional , COVID-19 , Atenção Plena , Humanos , Atenção Plena/métodos , COVID-19/prevenção & controle , Hong Kong/epidemiologia , Pandemias , Esgotamento Profissional/prevenção & controle , Hospitais
3.
Artigo em Inglês | MEDLINE | ID: mdl-35954786

RESUMO

Project GIFT is a pioneer research-based gifted education program which has been found to be effective in fostering holistic development of students in Hong Kong. Nevertheless, little is known whether the Project is beneficial to teachers. To investigate the changes in teachers after participating in the Project, we adopted a quasi-experimental design with pretest and posttest data collected from experimental and control groups in this study. A total of 2031 primary and secondary school teachers participated in the professional development program of the Project. They completed validated measures on teachers' knowledge of and attitudes toward gifted education, teaching behaviors, characteristics and competencies, in addition to well-being before and after participating in the program. Results of one-way ANCOVA showed that the program could promote teachers' knowledge of gifted education and specific teaching strategies to gifted learners. This study provides preliminary support for the program in promoting holistic professional development of participating teachers in gifted education. The theoretical and practical implications of the findings are discussed.


Assuntos
Pessoal de Educação , Estudantes , Currículo , Docentes , Hong Kong , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-35457698

RESUMO

In this study, we used a quasi-experimental research design with pretest and post-test data collected from an experimental group and a control group to investigate changes in students after participating in a school-based gifted education program (Project GIFT) in Hong Kong. There were 3207 successfully matched students (3rd to 9th graders) joining the Level 1 program (for all students) alone or both the Level 1 program and Level 2 program (for gifted students). Participants of the experimental and control groups completed validated measures on creativity, multiple intelligences, gifted characteristics, self-efficacy, psychological well-being, and satisfaction with life before and after participating in the program(s). One-way ANCOVA results revealed that students in the experimental groups showed positive changes after joining the program(s), with a greater impact for students joining both Level 1 and Level 2 programs. Students participating in both Level 1 and Level 2 programs displayed significant improvement in creativity, academic performance, logical-mathematical intelligence, intrapersonal intelligence, self-efficacy, autonomy, environmental mastery, and personal growth compared to the control counterparts. This study illustrates the benefits of the Level 1 and Level 2 programs in promoting the holistic development of the program participants.


Assuntos
Instituições Acadêmicas , Estudantes , Hong Kong , Humanos , Avaliação de Programas e Projetos de Saúde/métodos , Autoeficácia , Estudantes/psicologia
5.
JAMA Pediatr ; 176(4): 357-364, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35129606

RESUMO

IMPORTANCE: Most parenting programs target parents of children with severe behavioral problems. There is limited evidence on the effectiveness of universal parenting programs, especially for families with low income. OBJECTIVE: To evaluate the effectiveness of the KeySteps@JC Parent-Child Interaction Program for low-income families in Hong Kong. DESIGN, SETTING, AND PARTICIPANTS: A parallel, unblinded, cluster, randomized clinical trial was conducted from September 2018 to June 2019. Eight participating preschools in Hong Kong were randomly assigned (1:1) using an online randomization plan generator into intervention (immediate) and waiting list control (delayed) groups. Intervention participants included the parents of children in kindergarten grade 1. The results were processed by an intention-to-treat analysis. INTERVENTIONS: KeySteps@JC Parent-Child Interaction program. MAIN OUTCOMES AND MEASURES: The primary outcome was child behavioral problems, which were assessed using the Strength and Difficulties Questionnaire. Secondary outcomes were parental emotion coaching, involvement in child reading and play, and parent stress levels, which were assessed using Chinese-validated versions of the Parent Reading Belief Inventory, the Chinese Parent-Child Interaction Scale, the Emotion-Related Parenting Styles, and the Parental Stress Scale questionnaires. Parents in the intervention group participated in a training program consisting of 20 weekly 1.5-hour sessions on child behavior management, emotion coaching, dialogic reading, and interactive play. The primary hypothesis was that child behavior problems would be reduced after the intervention. The main analysis was a mixed-method regression with group status as the independent variable. RESULTS: A total of 267 parents (mean age, intervention group: 33.8 years; 95% CI, 32.9-34.7 years; waiting list group: 35.7 years; 95% CI, 34.5-36.9 years) participated in the program. The intervention group included 153 participants (57.3%), and the waiting list group included 114 participants (42.7%). Among the target children (mean age, intervention group: 3.5 years; 95% CI, 3.4-3.5 years; waiting list group: 3.4 years; 95% CI, 3.4-3.5 years), there were 88 boys (57.5%) in the intervention group and 59 boys (51.8%) in the waiting list group. At postintervention, the intervention group reported a statistically significant improvement in children's behavior (Cohen d, 0.29; 95% CI, 0.04-0.53); parents' use of emotion-coaching strategies, including feelings of uncertainty or ineffectiveness in emotion socialization (Cohen d, 0.26; 95% CI, 0.01-0.50) and parental rejection of negative emotion (Cohen d, 0.33; 95% CI, 0.08-0.57); and involvement in child reading (Cohen d, 0.17; 95% CI, -0.07 to 0.41). CONCLUSIONS AND RELEVANCE: The results of this randomized clinical trial provide promising evidence on the effectiveness of a multicomponent parenting intervention in preparing children from low-income families to be more socially and emotionally ready for school. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03615937.


Assuntos
Relações Pais-Filho , Poder Familiar , Adulto , Pré-Escolar , Emoções , Hong Kong , Humanos , Masculino , Poder Familiar/psicologia , Pais/psicologia , Instituições Acadêmicas
6.
J Pediatr ; 226: 258-265, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32629010

RESUMO

OBJECTIVE: To disentangle the pathways of parent technology use, parent-child interactions, child screen time, and child psychosocial difficulties among disadvantaged families in Hong Kong. STUDY DESIGN: Parents of 1254 3-year-old children from the KeySteps@JC project reported on the number of hours their children used electronic devices every day and evaluated their children's psychosocial behaviors using the Strengths and Difficulties Questionnaire. These parents also reported on their own digital device usage patterns and the frequency of parent-child interactions and provided sociodemographic data. Structural models were tested with parent technology use (independent variable), parent technological distractions and parent-child interactions and child screen time (mediators), child psychosocial problems (dependent variable), and children's age and sex and family socioeconomic status index (confounding variables). RESULTS: Parent distraction with technology during parent-child interactions completely mediated the overall association between parent problematic digital technology use and child screen use duration. Parent problematic digital technology use was positively and directly associated with child psychosocial difficulties. In addition, it was indirectly related to child psychosocial difficulties through technological distractions and reductions in parent-child interactions and increased media use by children. CONCLUSION: Higher parent digital technology usage was associated with reduced parent-child interactions and increased child screen time and psychosocial difficulties in disadvantaged families. These results suggest that limiting parents' use of electronic devices in front of their young children could be beneficial for childhood psychosocial development.


Assuntos
Tecnologia Digital , Relações Pais-Filho , Pais/psicologia , Tempo de Tela , Comportamento Social , Populações Vulneráveis/psicologia , Adulto , Comportamento Infantil , Pré-Escolar , Feminino , Hong Kong , Humanos , Masculino , Fatores Socioeconômicos , Inquéritos e Questionários
7.
Front Psychol ; 10: 2899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038350

RESUMO

This study aimed to investigate the learning effectiveness of reading picture books with EMPATHICS elements using dialogic reading techniques in enhancing young children's English language learning and creativity. EMPATHICS is an acronym of Emotion and Empathy, Meaning and Motivation, Perseverance, Agency and Autonomy, Time, Habits of Mind, Intelligences, Character Strengths, and Self Factors (Oxford, 2016). It adopted a quasi-experimental design, and 78 kindergarten children aged from 4 to 5 years old in a cluster group were randomly assigned to the experimental and control groups. Both groups read the same four picture books with their homeroom teachers, including two readers suggested in the curriculum and two picture books with enriched elements for 12 sessions over 8 weeks. A doubly multivariate analysis was used to measure the main time and group effects and the interaction effect on the performance of English receptive vocabulary, syntactic complexity, and verbal creativity of the two groups across three different times. There were significant differences only in the interactive effect on syntactic complexity. Children in the experimental condition gave responses with more complex syntactic structures. Significant time effects for receptive vocabulary, syntactic complexity, and verbal creativity were observed in all children. Reading enriched English texts better prepares children to creatively and effectively express themselves. This study extends previous research in two ways. First, this study is one of the few studies on the effectiveness of dialogic reading using EMPATHICS-enriched picture books among young language learners. Second, this study investigates the effects of dialogic teaching on English as a second language development in young children. The educational implications will be discussed.

9.
Front Psychol ; 9: 1090, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30008690

RESUMO

The multidimensional PERMA-H positive education model provided evaluation and education framework for the theoretical and practice development of positive psychology in schools. Character strengths use mediates the association of strength knowledge and well-being. Using the Assessment Program for Affective and Social Outcomes (2nd Version) (APASO-II), the Subjective Happiness Scale, and the Physical Health Subscale of the PERMA-profiler, a multidimensional measure of PERMA-H was validated using confirmatory factor analysis in the context of a positive education program evaluation in senior primary school students. The association of PERMA-H measurements with school well-being as measured by general satisfaction of school life, and levels of depression and anxiety, and the mediation mechanism of character strengths use in such association were studied using path analysis. A cross-sectional sample of 726 senior primary school students (i.e., grade 4-6) aged 8-13 from the two primary schools completed a baseline evaluation questionnaire of a positive education program. Satisfactory internal reliability of the scales was obtained with Cronbach's alpha coefficients < 0.70. The scales were generally positively and moderately inter-correlated, except for level of anxiety and depression symptoms which was negative. Good psychometric properties of APASO-II were evidenced from the factor structure of sub-scale scores conforming to six factors of the PERMA-H model by confirmatory factor analysis. Path analyses showed that the APASO-II factors together with measures of subject happiness and positive health as the multidimensional PERMA-H model of positive education differentially predicted general satisfaction of school life, level of anxiety and depression, and character strengths use. Character strengths use mediated the relationship of Positive Engagement with general satisfaction of school life. Positive education utilizes knowledge and research findings from positive psychology in schools to produce intended positive outcomes like enhanced well-being and reduced level of depression in students. This study provided a solid foundation for related scientific research and the understanding of the multidimensional framework of positive psychology concepts. Systematic promotion and longitudinal evaluation of positive education at the institutional level in Hong Kong can be achieved with the use of APASO-II and the positive education scales of subjective happiness and physical health.

10.
Front Psychol ; 8: 1680, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29018395

RESUMO

This study examined the effect of music listening on creative thinking through the lens of the arousal-and-mood hypothesis, which posits that emotional reactions (i.e., arousal and valence) mediate the effect of music listening on cognitive functioning. Participants were randomly assigned to three groups: a positive music group (n = 198), a negative music group (n = 195), and a control group (n = 191). Creative thinking and emotional reactions were assessed with the Test for Creative Thinking-Drawing Production and the Affect Grid, respectively. The results showed that both positively and negatively arousing music enhanced creative thinking. The results further revealed that arousal, regardless of valence, significantly mediated the music-creativity relationship. This study enriches the research on the arousal-and-mood hypothesis by (1) providing direct empirical testing on the mediating roles of emotional reactions; (2) including both positively and negatively arousing music in the study design; and (3) identifying that only arousal, and not valence, was a significant mediator in the music-creativity link.

11.
Psychol Rep ; 117(3): 845-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26595303

RESUMO

Humor is found to be an essential element of creative thinking in Western culture. In Eastern culture, however, the relationship between creativity and humor is ambivalent. This study examined the relationship among humor styles, creative personality traits, and creative thinking abilities. A sample of 118 Chinese undergraduates in Hong Kong was recruited to complete the Humor Styles Questionnaire, the three Creative Personality subscales of the Chinese Personality Assessment Inventory-2 (CPAI-2), and the Verbal Test of the Wallach-Kogan Creativity Tests. Results show that humor styles are uncorrelated with creative thinking abilities of flexibility, fluency, and originality, but affiliative humor and aggressive humor are correlated with creative personality traits of novelty and diversity. A hierarchical multiple regression shows that both humor styles and creative personality traits of novelty and diversity account for non-significant variance on creative thinking abilities. These findings largely support a hypothesized non-association between humor styles and creative measures. They also pose a sharp contrast to findings obtained in the West, in which humor styles are typically correlated with both creative thinking abilities and creative personality traits.


Assuntos
Criatividade , Inventário de Personalidade/estatística & dados numéricos , Personalidade , Pensamento/fisiologia , Senso de Humor e Humor como Assunto/psicologia , Adolescente , Adulto , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Estudantes/psicologia , Inquéritos e Questionários , Adulto Jovem
12.
Scoliosis ; 10: 28, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26442124

RESUMO

BACKGROUND: Many reports had been received on the application of antifibrinolytic medications on spinal corrective surgery and the surgical outcome evaluations of its efficacy on reducing blood loss. This study aimed to assess the efficacy of tranexamic acid (TXA) in reducing operative blood loss during posterior spinal fusion for the treatment of severe adolescent idiopathic scoliosis (AIS). METHODS: A retrospective cohort study was carried out on 90 (TXA = 55, Control = 35) AIS girls undergoing posterior spinal surgery. Patients in TXA group used TXA as an antifibrinolytic agent to reduce blood loss, while control group did not. Blood loss, haemoglobin change and amount of blood transfused was estimated from intraoperative measurement by anaesthesiologists. Demographics were compared using Student's T-test or Chi-square test where appropriate. Linear regression modelling was carried out between the use of TXA and total blood loss with controlling of confounding factors. RESULTS: Mean age and mean maximum major curve were 15.2 and 73°, and 15.3 and 63° in TXA and control groups respectively. TXA group showed significantly less intra-operative blood loss than the control group from intraoperative measurement (1.8 L vs. 3.9 L, p < 0.01) and volume of cell saver blood transfused back to patients (0.6 L vs. 1.7 L, p < 0.01). TXA group also showed significantly shorter total time taken for surgery (437 min vs. 502 min, p < 0.01), and total blood loss per surgical segment level (0.1 L vs. 0.3 L, p < 0.01). Regression models showed that the use of TXA decreased total blood loss by 794.3 ml after adjusting for maximum major curve, age, number of segments fused, bone graft, clotting capability, and infusion of coagulation factors. CONCLUSIONS: Patients undergoing posterior spinal corrective surgery with the use of TXA showed much reduced total blood loss, reduced use of transfused blood, much less cell saver blood transfused back to the patient. The total blood loss was decreased by after using TXA after controlling for maximum major curve, age, surgical parameters, clotting capability, and infusion of coagulation factors.

13.
Dev Psychol ; 50(3): 709-13, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23978299

RESUMO

In this study, we used a life span model to study the subjective perception of creative personality (CP) in emerging, young, middle-aged, and older Hong Kong Chinese adults. We also asked participants to estimate the approximate age by which people develop and lose CP across adulthood. We expected an interesting interplay between internalized age stereotypes and age-related differentiation in beliefs about personality development. Older adults perceived increases in both gains and losses in CP in old age. But they still maintained a similar level of self-perceived CP traits when compared with young participants. Emerging, young, and middle-aged adults were less optimistic about their creativity development into old age. Young adults, in contrast to older adults, believed that gains in CP began and ceased at an earlier age. Positive perceptions of CP in one's aging process may have implications for aging successfully.


Assuntos
Envelhecimento/psicologia , Criatividade , Desenvolvimento da Personalidade , Adolescente , Adulto , Idoso , Análise de Variância , Povo Asiático/psicologia , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Determinação da Personalidade , Inquéritos e Questionários , Adulto Jovem
14.
Int J Geriatr Psychiatry ; 27(9): 907-13, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21953859

RESUMO

OBJECTIVES: To examine the relationship between self-perceptions of aging and acute medical events in chronically institutionalized middle-aged and older persons with schizophrenia. METHODS: Participants were 83 persons with schizophrenia (30% women; mean age = 58.48, SD = 8.14) residing in a long-stay care home, who were without organic mental disorders, mental retardation, serious audiovisual impairment, and serious cognitive and physical impairment. They received assessments in body mass index, functional health, and global mental status, and responded to measures of self-perception of aging at baseline. Acute events that required medical attention were recorded for the next 3 months. RESULTS: 8% of the participants had acute medical events. Bivariate analysis suggested that number of comorbid medical conditions, mobility, Mini-Mental State Examination, and negative self-perception of aging were predictive of acute medical events. However, multivariate analysis (logistic regression) showed that only mobility (OR = 0.78, p = 0.04) and negative self-perception of aging (OR = 3.38, p = 0.02) had independent effects on acute medical events, with the latter being the stronger predictor. Positive aging self-perception, body mass index, and smoking were unrelated to medical events. CONCLUSIONS: Physical vulnerabilities may not be sufficient to explain the development of acute medical events in late-life schizophrenia. How individuals perceive their aging process, which is expected to regulate health behavior and help-seeking, may be an even more important factor. Further research should investigate whether such self-perceptions, which are probably rooted in stereotypes about aging socialized early in life, are modifiable in this population.


Assuntos
Envelhecimento/psicologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Autoimagem , Doença Aguda , Idoso , Doença Crônica , Feminino , Hong Kong , Humanos , Institucionalização , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Regressão
15.
FASEB J ; 20(3): 466-75, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507764

RESUMO

Hypoxia-inducible factors (HIFs) are ubiquitous transcription factors that mediate adaptation to hypoxia by inducing specific sets of target genes. It is well accepted that hypoxia induces accumulation and activity of HIFs by causing stabilization of their alpha subunits. We have demonstrated that hypoxia stimulates translation of HIF-1alpha and -2alpha proteins by distributing HIF-alpha mRNAs to larger polysome fractions. This requires influx of extracellular calcium, stimulation of classical protein kinase C-alpha (cPKC-alpha), and the activity of mammalian target of rapamycin, mTOR. The translational component contributes to approximately 40-50% of HIF-alpha proteins accumulation after 3 h of 1% O2. Hypoxia also inhibits general protein synthesis and mTOR activity; however, cPKC-alpha inhibitors or rapamycin reduce mTOR activity and total protein synthesis beyond the effects of hypoxia alone. These data show that during general inhibition of protein synthesis by hypoxia, cap-mediated translation of selected mRNAs is induced through the mTOR pathway. We propose that calcium-induced activation of cPKC-alpha hypoxia partially protects an activity of mTOR from hypoxic inhibition. These results provide an important physiologic insight into the mechanism by which hypoxia-stimulated influx of calcium selectively induces the translation of mRNAs necessary for adaptation to hypoxia under conditions repressing general protein synthesis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Sinalização do Cálcio , Hipóxia Celular/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Biossíntese de Proteínas , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/análise , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Benzilaminas/farmacologia , Butadienos/farmacologia , Carbazóis/farmacologia , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Cicloeximida/farmacologia , Flavonoides/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Indóis/farmacologia , Ionomicina/farmacologia , Isoquinolinas/farmacologia , Rim , Nitrilas/farmacologia , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Polirribossomos/metabolismo , Proteína Quinase C-alfa/antagonistas & inibidores , Proteína Quinase C-alfa/metabolismo , Proteínas Quinases/fisiologia , Inibidores da Síntese de Proteínas/farmacologia , Capuzes de RNA/fisiologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Ratos , Sirolimo/farmacologia , Sulfonamidas/farmacologia , Serina-Treonina Quinases TOR
16.
J Neurochem ; 94(5): 1288-96, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16000154

RESUMO

Transcription co-activators and histone acetyltransferases, p300 and cyclic AMP responsive element-binding protein-binding protein (CBP), participate in hypoxic activation of hypoxia-inducible genes. Here, we show that exposure of PC12 and cells to 1-10% oxygen results in hyperphosphorylation of p300/CBP. This response is fast, long lasting and specific for hypoxia, but not for hypoxia-mimicking agents such as desferioxamine or Co2+ ions. It is also cell-type specific and occurs in pheochromocytoma PC12 cells and the carotid body of rats but not in hepatoblastoma cells. The p300 hyperphosphorylation specifically depends on the release of intracellular calcium from inositol 1,4,5-triphosphate (IP3)-sensitive stores. However, it is not inhibited by pharmacological inhibitors of any of the kinases traditionally known to be directly or indirectly calcium regulated. On the other hand, p300 hyperphosphorylation is inhibited by several different inhibitors of the glucose metabolic pathway from generation of NADH by glyceraldehyde 3-phosphate dehydrogenase, through the transfer of NADH through the glycerol phosphate shuttle to ubiquinone and complex III of the mitochondrial respiratory chain. Inhibition of IP3-sensitive calcium stores decreases generation of ATP, and this inhibition is significantly stronger in hypoxia than in normoxia. We propose that the NADH glycerol phosphate shuttle participates in generating a pool of ATP that serves either as a co-factor or a modulator of the kinases involved in the phosphorylation of p300/CBP during hypoxia.


Assuntos
Hipóxia/metabolismo , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Animais , Cálcio/metabolismo , Corpo Carotídeo/efeitos dos fármacos , Corpo Carotídeo/metabolismo , Corpo Carotídeo/patologia , Linhagem Celular , Proteína p300 Associada a E1A , Glucose/metabolismo , Humanos , Hipóxia/patologia , Hipóxia/fisiopatologia , Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Oxigênio/farmacologia , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley
17.
Hypertension ; 42(6): 1130-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14597643

RESUMO

Chronic intermittent hypoxia, a characteristic feature of sleep-disordered breathing, induces hypertension through augmented sympathetic nerve activity and requires the presence of functional carotid body arterial chemoreceptors. In contrast, chronic sustained hypoxia does not alter blood pressure. We therefore analyzed the biosynthetic pathways of catecholamines in peripheral nervous system structures involved in the pathogenesis of intermittent hypoxia-induced hypertension, namely, carotid bodies, superior cervical ganglia, and adrenal glands. Rats were exposed to either intermittent hypoxia (90 seconds of room air alternating with 90 seconds of 10% O2) or to sustained hypoxia (10% O2) for 1 to 30 days. Dopamine, norepinephrine, epinephrine, dihydroxyphenylacetic acid, and 5-hydroxytyptamine contents were measured by high-performance liquid chromatography. Expression of tyrosine hydroxylase and its phosphorylated forms, dopamine beta-hydroxylase, phenylethanolamine N-methyltransferase, and GTP cyclohydrolase-1 were determined by Western blot analyses. Both sustained and intermittent hypoxia significantly increased dopamine and norepinephrine content in carotid bodies but not in sympathetic ganglia or adrenal glands. In carotid bodies, both types of hypoxia augmented total levels of tyrosine hydroxylase protein and its phosphorylation on serines 19, 31, 40, as well as levels of GTP cyclohydrolase-1. However, the effects of intermittent hypoxia on catecholaminergic pathways were significantly smaller and delayed than those induced by sustained hypoxia. Thus, attenuated induction of catecholaminergic phenotype by intermittent hypoxia in carotid body may play a role in development of hypertension associated with sleep-disordered breathing. The effects of both types of hypoxia on expression of catecholaminergic enzymes in superior cervical neurons and adrenal glands were transient and small.


Assuntos
Catecolaminas/biossíntese , Hipóxia/metabolismo , Neurônios/metabolismo , Sistemas Neurossecretores/metabolismo , Sistema Nervoso Simpático/metabolismo , Glândulas Suprarrenais/metabolismo , Animais , Pressão Sanguínea , Corpo Carotídeo/metabolismo , GTP Cicloidrolase/metabolismo , Hipertensão/etiologia , Hipóxia/complicações , Hipóxia/fisiopatologia , Masculino , Sistemas Neurossecretores/citologia , Ratos , Gânglio Cervical Superior/metabolismo , Sistema Nervoso Simpático/citologia
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