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1.
Dev Psychol ; 57(8): 1318-1324, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34591574

RESUMO

Interpersonal trust is a key component of cooperation, helping support the complex social networks found across societies. Trust typically involves two parties, one who trusts by taking on risk through investment in a second party, who can be trustworthy and produce mutual benefits. To date, the developmental literature has focused primarily on the trustor, meaning we know little about the ontogeny of trustworthiness. Whereas trusting can be motivated by self-interest, one-shot trustworthiness is more squarely situated in the prosocial domain, involving a direct tradeoff between self-interest and others' interests. However, this raises the question of whether trustworthiness is distinct from generosity. In this preregistered study, we examine the origins of trustworthiness using an intuitive version of the Trust Game, in which a first party invests resources in a second party who can split the gains. We recruited N = 118 5-to-8 year-old American children (Mage = 6.94, n = 59 girls, 57% White, 88% of parents with bachelor's degree or higher), split between the Trustworthiness condition, where another party's investment is instrumental for obtaining greater resources, and the Generosity condition, where the other party is a passive recipient. We found that children in the Trustworthiness condition shared significantly more resources than those in the Generosity condition. Further, children in the Trustworthiness condition predicted that the first party expected them to share a greater number of resources. Overall, these results demonstrate that trustworthiness is distinct from generosity in childhood and suggest that children spontaneously grasp and engage in a key aspect of cooperation. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Força da Mão , Pais , Criança , Feminino , Humanos
2.
Clin Exp Rheumatol ; 28(2): 215-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20483043

RESUMO

OBJECTIVES: The purpose of the present study was to produce an Italian version of the Canadian Occupational Performance Measure (COPM) in a group of patients with Ankylosing Spondylitis (AS) and examine the psychometric properties of this version, evaluating its internal consistency, external validity and reliability. Responsiveness and feasibility were also taken into account. METHODS: The Italian COPM, the Italian version of the COPM, was administered to 30 Caucasian patients affected by AS (24 males, 6 females, median age 48 yrs, range 32-67, median disease duration 14 yrs, range 1-30 yrs) together with the Bath Ankylosing Spondylitis Functional Index (BASFI), the Bath Ankylosing Spondylitis Disease Activity (BASDAI) and the Italian version of the Health Assessment Questionnaire (HAQ). Internal consistency was evaluated with Cronbach's alpha for reliability. Construct validity of the COPM was evaluated by a correlation between the BASFI, BASDAI and HAQ scores. Test-retest reliability was assessed by the Intraclass correlation coefficient. Responsiveness and feasibility were also considered. RESULTS: All patients completed the validation study. The questionnaire was internally consistent (alpha coefficient=0.774). A significant correlation was recorded between the COPM and the BASFI (rho=-0.566, p<0.01), BASDAI (rho=-0.491, p<0.01). Test-retest reliability showed a good correlation coefficient and it was confirmed by Bland-Altman method. CONCLUSIONS: The Italian COPM is a valid and reliable instrument focused to detect change in a client's perception of occupational performance over time, in AS patients. Our results confirm the utility of this questionnaire to measure outcome and in planning treatment intervention for patients with AS.


Assuntos
Avaliação da Deficiência , Psicometria/normas , Espondilite Anquilosante/fisiopatologia , Inquéritos e Questionários/normas , Adulto , Idoso , Canadá , Estudos de Viabilidade , Feminino , Humanos , Itália , Idioma , Masculino , Pessoa de Meia-Idade , Ocupações , Reprodutibilidade dos Testes
3.
Clin Exp Rheumatol ; 27(6): 977-80, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20149315

RESUMO

OBJECTIVES: To assess the validity of the BASRI and m-SASSS scores for the radiological axial involvement in psoriatic arthritis (PsA). Secondary end-points were to report on clinical, functional and radiographic characteristics of axial involvement. METHODS: Inclusion criteria were satisfaction of the CASPAR criteria and the presence of clinical, functional and/or radiological axial involvement. Three observers scored the radiographs by BASRI and m-SASSS. The construct validity was assessed by examining the correlation of instruments with patient reported outcomes and anthropometric measures. The reliability and the feasibility of the scores were also considered. RESULTS: Seventy-seven patients were enrolled (58 M, 19 F, mean age 49.4 + or - 10.8 yrs, disease duration 13.9 + or - 7.9 yrs). Both instruments showed some modest but significant correlation with clinical measures. When compared, the BASRI showed a correlation with BASMI (rho=0.47, p<0.001), cervical rotation (rho=-0.49, p<0.001), tragus to wall (rho=0.34, p<0.01) and occiput to wall (rho=0.49, p<0.001), modified Schober test (rho=-0.24, p<0.05) and RLDQ (rho=-0.24, p<0.05). When compared, m-SASSS showed a correlation with BASMI (rho=0.39, p<0.001), cervical rotation (rho=-0.41, p<0.001), tragus to wall (rho=0.31, p<0.01) and occiput to wall (rho=0.42, p<0.001), modified Schober and Schober test (rho=-0.34, p<0.001; rho= -0.32, p<0.01), finger to floor (rho=0.37, p<0.01). No correlation was found with BASFI, BASDAI and HAQ. Test-retest showed a good reliability of the scores. Both were feasible but BASRI was the quickest. CONCLUSION: Our results showed that BASRI and m-SASSS were valid instruments for use in spondylitis associated with psoriatic arthritis. Longitudinal data is required to provide sensitivity to change of the two scores.


Assuntos
Artrite Psoriásica/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Espondilite/diagnóstico por imagem , Adulto , Artrite Psoriásica/complicações , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Radiografia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Espondilite/complicações , Inquéritos e Questionários
4.
Rheumatology (Oxford) ; 46(11): 1672-5, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17893100

RESUMO

OBJECTIVE: To assess the effectiveness of rehabilitation in a group of patients with active ankylosing spondylitis (AS) by the Assessment in Ankylosing Spondylitis (ASAS) Working Group response criteria. METHODS: Fifty-two active AS patients consecutively admitted to a rehabilitation inpatient clinic were enrolled. Patients underwent a 3-week intensive rehabilitation programme and were then discharged with home exercises. The primary outcome measure was the proportion of patients achieving a response based on ASAS 20 at discharge, and at 6 and 12 weeks after. Secondary outcome measures included an improvement in the Revised Leeds Disability Questionnaire (RLDQ) and function expressed as anthropometric measures. RESULTS: The ASAS 20 was achieved in 46 patients (88.5%) at the end of the rehabilitation, in 31 (59.6%) and in 17 (32.7%) patients at 6 and 12 weeks follow-up, respectively. The percentage of ASAS 20 responders statistically declined over time measured from the end of rehabilitation compared with 6 (P < 0.001) and 12 weeks follow-up (P < 0.001). CONCLUSION: The present study shows the effectiveness of rehabilitation as assessed by the ASAS 20, a validated instrument for treatment response, suggesting its usage in rehabilitation settings. Moreover, the results obtained show that the effectiveness of the intensive inpatient rehabilitation declined over time.


Assuntos
Índice de Gravidade de Doença , Espondilite Anquilosante/reabilitação , Adulto , Antropometria , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Avaliação de Programas e Projetos de Saúde , Centros de Reabilitação , Resultado do Tratamento
5.
Eur J Clin Nutr ; 60(4): 529-37, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16391591

RESUMO

OBJECTIVE: The purpose of this study was to determine whether supplements of plant sterols and/or glucomannan improve lipid profile and cholesterol biosynthesis in mildly hypercholesterolemic type II diabetic and non-diabetic subjects and to compare the response of these two subject groups to the treatments. DESIGN: A randomized, crossover study consisting of four phases of 21 days, with each phase separated by a 28-day washout. SETTING: The Mary Emily Clinical Nutrition Research Unit of McGill University. SUBJECTS: Eighteen non-diabetic individuals and 16 type II diabetic individuals aged 38-74 years. INTERVENTIONS: Subjects were supplemented with plant sterols (1.8 g/day), glucomannan (10 g/day), a combination of glucomannan and plant sterols, and a placebo, provided in the form of bars. RESULTS: Overall plasma cholesterol concentrations were lowered (P<0.05) after combination treatment (4.72+/-0.20 mmol/l) compared to control (5.47+/-0.18 mmol/l). Plasma low-density lipoprotein (LDL) cholesterol concentrations were decreased (P<0.05) after glucomannan (3.16+/-0.14 mmol/l) and combination treatments (2.95+/-0.16 mmol/l) compared to control (3.60+/-0.16 mmol/l). The results of lipid profiles did not differ between subject groups. Overall plasma lathosterol concentrations, an index of cholesterol biosynthesis, were lowered (P<0.05) after the combination treatment compared to the plant sterol treatment. CONCLUSIONS: The results suggest that glucomannan and a combination of glucomannan and plant sterols substantially improves plasma LDL cholesterol concentrations. SPONSORSHIP: Forbes Medi-Tech Inc., Vancouver, British Columbia, Canada.


Assuntos
LDL-Colesterol/sangue , Colesterol/biossíntese , Diabetes Mellitus Tipo 2/metabolismo , Hipercolesterolemia/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Mananas/farmacologia , Fitosteróis/farmacologia , Adulto , Idoso , Catárticos/farmacologia , Colesterol/sangue , Estudos Cross-Over , Diabetes Mellitus Tipo 2/complicações , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/metabolismo , Masculino , Mananas/uso terapêutico , Pessoa de Meia-Idade , Fitosteróis/uso terapêutico
6.
Rheumatology (Oxford) ; 44(5): 666-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15757970

RESUMO

OBJECTIVE: The purpose of the present study was to produce an Italian version of the Revised Leeds Disability Questionnaire (LDQ) in a group of patients with ankylosing spondylitis, and to examine the psychometric properties of this version, evaluating its internal consistency, external validity and reliability. METHODS: The LDQ was administered to 60 Caucasian patients affected by ankylosing spondylitis (50 males, 10 females, mean age 46.1 +/- 14.2 yr, range 22-74, median disease duration 4.5 yr, range 1-24) together with the Italian version of the Stanford Health Assessment Questionnaire (HAQ), and anthropometric measurements. Thirty patients completed the questionnaire after a 10-day interval. Internal consistency was evaluated with Cronbach's alpha coefficient of reliability. Construct validity of the LDQ was evaluated using the correlation between the HAQ and anthropometric measurements. Test-retest reliability was assessed with the intraclass correlation coefficient. RESULTS: All patients completed the validation study. The questionnaire was internally consistent (alpha=0.90). A significant correlation was recorded between the LDQ and the HAQ score (rho=0.841, P<0.01) and the anthropometric measurements. Test-retest reliability showed a good correlation coefficient (intraclass correlation=0.97). CONCLUSION: The Italian LDQ is a valid and reliable instrument for detecting and measuring functional disability in patients with ankylosing spondylitis. Our results confirm the utility of this questionnaire as a valid and feasible functional measure for patients with ankylosing spondylitis.


Assuntos
Avaliação da Deficiência , Espondilite Anquilosante/reabilitação , Adulto , Idoso , Antropometria/métodos , Comparação Transcultural , Feminino , Indicadores Básicos de Saúde , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Psicometria , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Espondilite Anquilosante/fisiopatologia , Inquéritos e Questionários
7.
Skeletal Radiol ; 33(8): 451-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15224172

RESUMO

OBJECTIVE: To evaluate gadolinium-enhanced MR imaging in athletes with chronic groin pain and correlate with the clinical features. DESIGN AND PATIENTS: MR examinations performed in 52 athletes (51 male, 1 female; median age 26 years) with chronic groin pain and 6 asymptomatic control athletes (6 male; median age 29 years) were independently reviewed by two radiologists masked to the clinical details. Symptom duration (median 6 months) and clinical side of severity were recorded. Anatomical areas in the pelvis were scored for abnormality (as normal, mildly abnormal or abnormal) and an overall assessment for side distribution of abnormality was recorded, initially without post-gadolinium sequences and then, 3 weeks later (median 29 days), the post-gadolinium sequences only. Correlation between radiological and clinical abnormality was calculated by Spearman's correlation. RESULTS: Abnormal anterior pubis and enthesis enhancement significantly correlated with clinical side for both radiologists (both P=0.008). Abnormal anterior pubis and adductor longus enthesis oedema was significant for one radiologist ( P=0.009). All other features showed no significant correlation ( P>0.05). In the control cases there was no soft tissue abnormality but symphyseal irregularity was present ( n=2). For both radiologists assessment of imaging side severity significantly correlated with clinical side for post-gadolinium ( P=0.048 and P=0.023) but not non-gadolinium sequences ( P>0.05). CONCLUSION: The extent and side of anterior pubis and adductor longus enthesis abnormality on MR imaging significantly and reproducibly correlates with the athletes' current symptoms in chronic adductor-related groin pain.


Assuntos
Traumatismos em Atletas/diagnóstico , Transtornos Traumáticos Cumulativos/diagnóstico , Virilha , Imageamento por Ressonância Magnética , Músculo Esquelético/patologia , Dor/etiologia , Traumatismos dos Tendões/diagnóstico , Tendões/patologia , Adolescente , Adulto , Doença Crônica , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio DTPA , Humanos , Masculino , Sínfise Pubiana/patologia , Reto do Abdome/patologia , Coxa da Perna
8.
Int J Obes Relat Metab Disord ; 27(1): 95-102, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12532160

RESUMO

OBJECTIVE: To determine the effects of long-term consumption of medium chain (MCT) versus long chain triglycerides (LCT) on energy expenditure (EE), substrate oxidation and body composition. HYPOTHESIS: MCT consumption will not result in greater EE, substrate oxidation, and body weight loss compared with LCT consumption. RESEARCH METHODS AND PROCEDURES: Seventeen healthy obese women participated in this randomized, crossover inpatient trial. Meals were prepared and consumed on site for two periods of 27 days. Diets containing 40% of energy as fat, with treatment fat comprising 75% of the total fat, were designed to supply each subject with their individual weight-maintaining energy needs. The MCT diet contained 67% of treatment fat as MCT oil (49% octanoate, 50% decanoate) whereas the LCT diet contained exclusively beef tallow as treatment fat. Body composition was assessed by magnetic resonance imaging (MRI) on day 1 and 28 of each phase while energy expenditure was measured on day 2 and 27. RESULTS: Changes in total and subcutaneous adipose tissue volumes following consumption of MCT and LCT were not different (-0.61+/-0.38 l vs -0.54+/-0.48 l and -0.58+/-0.35 l vs -0.48+/-0.40 l, respectively). Average EE and fat oxidation were greater (P<0.05) during MCT than LCT consumption (0.95+/-0.019 vs 0.90+/-0.024 kcal/min, respectively, for EE and 0.080+/-0.0026 vs 0.075+/-0.0022 g/min, respectively for fat oxidation). DISCUSSION: These results show that long-term consumption of MCT enhances EE and fat oxidation in obese women, when compared to LCT consumption. The difference in body composition change between MCT and LCT consumption, although not statistically different, was consistent with differences predicted by the shifts in EE. It can be concluded that substitution of MCT for LCT in a targeted energy balance diet may prevent long-term weight gain via increased EE.


Assuntos
Tecido Adiposo/metabolismo , Obesidade/metabolismo , Triglicerídeos/administração & dosagem , Adulto , Composição Corporal , Índice de Massa Corporal , Estudos Cross-Over , Metabolismo Energético , Feminino , Humanos , Oxirredução/efeitos dos fármacos , Triglicerídeos/química , Redução de Peso/efeitos dos fármacos
9.
Surgery ; 130(4): 722-8; discussion 728-31, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11602904

RESUMO

BACKGROUND: Vasculobiliary injury (VBI) is a well-recognized complication of laparoscopic cholecystectomy (LC). In patients with failed primary management of bile duct injury (BDI), an assessment of the hepatic arterial system may be important to determine the presence of VBI. This study was conducted to determine the incidence of VBI in patients with failed primary management of LC-related BDI and to establish a potential correlation between the level of BDI and the incidence of VBI. METHODS: A retrospective review was conducted on 18 patients referred for failed primary management of LC-related BDI who underwent prospective arteriography as part of the preoperative work-up. RESULTS: Of the 18 patients who sustained BDI, Bismuth level 4 lesions were found in 7 patients (39%), level 3 in 8 patients (44%), and level 2 in 3 patients (17%). VBI was identified on arteriography in 11 patients (61%). VBI was present in 71% of patients with level 4 lesions, 63% of patients with level 3 lesions, and 33% of patients with level 2 lesions. The time interval from primary management to its failure was longer in VBI than in BDI alone. CONCLUSIONS: We have observed a high incidence of VBI in patients with failed primary management of LC-related BDI. Arterial disruption may affect the outcome of primary management of BDI.


Assuntos
Ductos Biliares/lesões , Colecistectomia Laparoscópica/efeitos adversos , Artéria Hepática/lesões , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos
11.
Int J Colorectal Dis ; 16(4): 211-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11515679

RESUMO

Fibromyalgia (FM) syndrome and irritable bowel syndrome (IBS) are functional disorders in which altered somatic and or visceral perception thresholds have been found. The aim of this study was to evaluate the prevalence of FM in a group of patients with IBS and the possible association of FM with patterns and severity of the intestinal disorder. One hundred thirty consecutive IBS patients were studied. The IBS was divided into four different patterns according to the predominant bowel symptom and into three levels of severity using a functional severity index. All patients underwent rheumatological evaluation for number of positive tender points, number of tender and swollen joints, markers of inflammation, and presence of headache and weakness. Moreover, patients' assessments of diffuse pain, mood and sleep disturbance, anxiety, and fatigue were also measured on a visual analogue scale. The diagnosis of FM was made based on American College of Rheumatology classification criteria. Nonparametric tests were used for statistical analysis. Fibromyalgia was found in 20% of IBS patients. No statistical association was found between the presence of FM and the type of IBS but a significant association was found between the presence of FM and severity of the intestinal disorder. The presence of FM in IBS patients seems to be associated only with the severity of IBS. This result confirms previous studies on the association between the two syndromes.


Assuntos
Doenças Funcionais do Colo/complicações , Fibromialgia/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Índice de Gravidade de Doença
13.
Eur Heart J ; 22(16): 1496-503, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11482923

RESUMO

OBJECTIVES: This study assessed the prognostic value of peak cardiac power output, measured non-invasively during maximal cardiopulmonary exercise testing, against other exercise-derived haemodynamic variables in patients with chronic congestive heart failure. METHOD AND RESULTS: Two hundred and nineteen unselected, consecutive patients with congestive heart failure (166 men, mean (+/-SD) age of 56+/-13 years) who underwent maximal symptom limited cardiopulmonary treadmill exercise testing with non-invasive estimation of cardiac output using carbon dioxide re-breathing techniques, were followed-up for a mean period of 4.64 (4.47--4.82, 95% CI) years. Cardiac power output was calculated from the product of cardiac output and mean arterial blood pressure. All cause mortality was 12.3% (27 deaths). Peak and resting cardiac power output, peak mean arterial blood pressure, peak and resting cardiac output and peak VO(2)were all predictive of outcome on univariate analyses. Peak cardiac power output, either entered continuously or categorically with a cut-off value of 1.96 watts, was the only independent predictor of mortality (P=0.0004 for values < or >1.96 watts and P=0.001 for continuous values) using multivariate analysis. A relative risk ratio of 5.08 (1.94-13.3, 95% CI) was obtained for a cardiac power output <1.96 watts. CONCLUSION: Peak cardiac power output is an independent predictor of mortality that can be measured non-invasively using cardiopulmonary exercise testing. It can give further prognostic power to a peak VO(2)in the assessment of patients with congestive heart failure.


Assuntos
Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Insuficiência Cardíaca/fisiopatologia , Consumo de Oxigênio/fisiologia , Adulto , Idoso , Análise de Variância , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
14.
Sex Transm Infect ; 77(2): 107-10, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11287688

RESUMO

OBJECTIVES: To determine the current practice of smear taking in sexually transmitted infection (STI) clinics within the United Kingdom; what proportion of smears are taken within the national guidelines; whether clinics are screening women not covered by the national screening programme. To compare the abnormality rates of routine and opportunistic (that is, in addition to the screening recommendations) smears; the abnormality rates of smears taken within STI clinics with those taken within the community setting. METHODS: A questionnaire was circulated to all clinics in May 1998. Details of screening practice were requested. The clinics then prospectively collected details of patient's age, GP registration, date and result of previous smear, and current result of all smears taken between 11 May 1998 and 25 May 1998. RESULTS: There were 1828 smears taken in the 2 week period; 504 (27.6%) were opportunistic. Opportunistic smears had marginal significantly increased rates of low grade abnormalities but lower (but not statistically significant) high grade abnormalities than in routine smears. 231 (12.6%) of the women were not registered with a GP so would not be included in the national programme. The national rates of abnormalities were significantly higher in the STI clinics compared with the community setting. CONCLUSION: The majority of smears taken within STI clinics fall within the national guidelines, and 12.6% of the women would probably not otherwise have been screened. The rates of abnormality were significantly higher in the STI clinics but smears taken opportunisticly were less likely to have high grade abnormalities. There is no evidence from this study to support the practice of additional smears in the presence of an effective national cytology screening programme.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Programas de Rastreamento/organização & administração , Esfregaço Vaginal/estatística & dados numéricos , Venereologia/organização & administração , Adolescente , Adulto , Idoso , Feminino , Fidelidade a Diretrizes , Humanos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia
15.
Environ Pollut ; 115(3): 395-404, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11789920

RESUMO

Atmospheric chemical composition affects foliar chemical composition, which in turn influences the dynamics of both herbivory and decomposition in ecosystems. We assessed the independent and interactive effects of CO2 and O3 fumigation on foliar chemistry of quaking aspen (Populus tremuloides) and paper birch (Betula papyrifera) at a Free-Air CO2 Enrichment (FACE) facility in northern Wisconsin. Leaf samples were collected at five time periods during a single growing season, and analyzed for nitrogen. starch and condensed tannin concentrations, nitrogen resorption efficiencies (NREs), and C:N ratios. Enriched CO2 reduced foliar nitrogen concentrations in aspen and birch; O3 only marginally reduced nitrogen concentrations. NREs were unaffected by pollution treatment in aspen, declined with 03 exposure in birch, and this decline was ameliorated by enriched CO2. C:N ratios of abscised leaves increased in response to enriched CO2 in both tree species. O3 did not significantly alter C:N ratios in aspen, although values tended to be higher in + CO2 + O3 leaves. For birch, O3 decreased C:N ratios under ambient CO2 and increased C:N ratios under elevated CO2. Thus, under the combined pollutants, the C:N ratios of both aspen and birch leaves were elevated above the averaged responses to the individual and independent trace gas treatments. Starch concentrations were largely unresponsive to CO2 and O3 treatments in aspen. but increased in response to elevated CO2 in birch. Levels of condensed tannins were negligibly affected by CO2 and O3 treatments in aspen, but increased in response to enriched CO2 in birch. Results from this work suggest that changes in foliar chemical composition elicited by enriched CO2 are likely to impact herbivory and decomposition, whereas the effects of O3 are likely to be minor, except in cases where they influence plant response to CO2.


Assuntos
Betula/efeitos dos fármacos , Dióxido de Carbono/farmacologia , Ozônio/farmacologia , Folhas de Planta/efeitos dos fármacos , Salicaceae/efeitos dos fármacos , Betula/química , Betula/fisiologia , Carbono/metabolismo , Ecossistema , Agricultura Florestal , Nitrogênio/metabolismo , Folhas de Planta/química , Folhas de Planta/fisiologia , Salicaceae/química , Salicaceae/fisiologia , Amido/metabolismo , Taninos/metabolismo , Árvores/química , Árvores/efeitos dos fármacos , Árvores/fisiologia , Estados Unidos
17.
J Lipid Res ; 41(5): 697-705, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10787430

RESUMO

It has been suggested that phytosterol and phytostanol esters possess similar cholesterol-lowering properties, however, whether mechanisms responsible are identical has not been addressed. To address this question, cholesterol plasma levels, absorption, biosynthesis, and turnover were measured in 15 hypercholesterolemic subjects consuming prepared diets each over 21 d using a cross-over design. Diets contained either i) margarine (M), ii) margarine with phytosterol esters (MSE) (1.84 g/d), or iii) margarine with phytostanol esters (MSA) (1.84 g/d). Cholesterol absorption was measured using the ratio of [(13)C]cholesterol(oral):D(7)-cholesterol(IV); biosynthesis using D incorporation from D(2)O and turnover by D(7)-cholesterol(IV) decay rates. Plasma total cholesterol level at d 21/22 was lower (P < 0. 05) for MSE (13.4%) but not MSA (10.2%) versus M (6.0%) diets. Plasma low density lipoprotein-cholesterol (LDL-C) mean reductions at d 21/22 were larger (P < 0.05) for MSE (12.9%) and MSA (7.9%) compared with M (3.9%). Plasma TG and high density lipoprotein-cholesterol (HDL-C) levels did not differ across diets. Cholesterol absorption was reduced (P < 0.05) 36.2 and 25.9% at d 21 for MSE and MSA versus M, while cholesterol biosynthesis was reciprocally increased (P < 0.05) 53.3 and 37.8% for MSE and MSA versus M, respectively. Cholesterol turnover was not influenced by diet. These data indicate that plant sterol and stanol esters differentially lower circulating total and LDL cholesterol levels by suppression of cholesterol absorption in hypercholesterolemic subjects.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol/sangue , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Fitosteróis/farmacologia , Absorção , Adulto , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/química , LDL-Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/dietoterapia , Cinética , Masculino , Margarina , Pessoa de Meia-Idade , Fitosteróis/administração & dosagem , Fitosteróis/química
18.
Cell Immunol ; 197(2): 99-107, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10607427

RESUMO

The voltage-gated potassium channel, Kv1.3, is specifically expressed on human lymphocytes, where it controls membrane potential and calcium influx. Blockade of Kv1.3 channels by margatoxin was previously shown to prevent T cell activation and attenuate immune responses in vivo. In the present study, a triterpene natural product, correolide, was found to block Kv1.3 channels in human and miniswine T cells by electrophysiological characterization. T cell activation events, such as anti-CD3-induced calcium elevation, IL-2 production, and proliferation were inhibited by correolide in a dose-dependent manner. More potent analogs were evaluated for pharmacokinetic profiles and subsequently tested in a delayed-type hypersensitivity (DTH) response to tuberculin in the miniswine. Two compounds were dosed orally, iv, or im, and both compounds suppressed DTH responses, demonstrating that small molecule blockers of Kv1.3 channels can act as immunosuppressive agents in vivo. These studies establish correolide and its derivatives as novel immunosuppressants.


Assuntos
Imunossupressores/farmacologia , Bloqueadores dos Canais de Potássio , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio , Linfócitos T/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Humanos , Imunossupressores/química , Ativação do Canal Iônico , Canal de Potássio Kv1.3 , Estrutura Molecular , Suínos , Porco Miniatura , Linfócitos T/imunologia , Triterpenos/química
19.
Anal Chem ; 71(20): 4734-9, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10546538

RESUMO

The aldonitrile pentaacetate and other derivatives lack ions in the electron ionization (EI) spectra possessing an intact hexose structure and thus must be analyzed by chemical ionization GC/MS in order to study multiple isotopomers. We report methods for quantitation of hexose di-O-isopropylidene acetate (IPAc) or pentafluorobenzoyl (PFBz) esters. These were prepared in a two-step procedure using inexpensive reagents that do not adversely impact the isotopomer structure of the sugar. The acetate derivative possesses an abundant [M - CH3] ion in the EI spectrum which is suitable for quantitative analysis of isotopomers. The negative chemical ionization (NCI) spectrum of the corresponding pentafluorobenzoyl derivative has a dominant molecular anion. Moreover, the PFBz derivative is about 100-fold more sensitive than the acetate, which offers some advantages for analysis of minor hexoses found in plasma. Isotopic calibration curves of [U-13C]glucose are linear over the 0.1-60% tracer/tracee range tested. The useful range for isotopic tracer studies is 25-2500 pmol for EI analysis of the acetate derivative and 0.1-55 pmol for NCI analysis of PFBz derivative (sample amount injected). For most studies where sample size is not limited, EI-GC/MS analysis of the IPAc derivative is preferred. NCI-GC/MS analysis is reserved when sample size is limiting or when studies involve hexoses other than glucose that are normally present at low concentration.


Assuntos
Alcenos/análise , Monossacarídeos/análise , Alcenos/sangue , Glicemia/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indicadores e Reagentes , Monossacarídeos/sangue
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