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1.
J Frailty Aging ; 12(2): 143-149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36946712

RESUMO

BACKGROUND: Natural dietary compounds that can modulate the inflammation process have the potential to improve physical function through a number of biological pathways, and thus may represent an alternative approach to avert functional decline compared to more time-burdening lifestyle interventions. In this pilot trial, we tested the feasibility and explored the effect of a nutritional compound, Curcumin C3 Complex® for improving physical function and muscle strength in moderately functioning older adults with low-grade inflammation. METHODS: Moderately functioning (short physical performance battery, SPPB <10) and sedentary older adults (>65 years) with low-grade systemic inflammation (c-reactive protein >1mg/dL) were randomized to receive Curcumin C3 Complex® (n=9) (1000mg/day) or placebo (n=8) groups for 12 weeks. All participants (age range: 66-94 years, 8 females and 9 males) underwent functional testing (SPPB and walking speed by the 400-meter walk test) and lower-limb strength (knee flexion and extension peak torque by the Biodex test) at baseline and 12 weeks. Venous blood was collected at baseline, 4, 8 and 12 weeks for safety blood chemistry analyses and biomarkers of inflammation. RESULTS: A total of 17 participants were randomized and completed the study. Adherence was high (> 90%) and there were no adverse events reported or abnormal blood chemistries reported. Based on effect sizes, participants in the Curcumin C3 Complex® group demonstrated large effect sizes in the SPPB (Cohen's effect size d=0.75) and measures of knee extension (d=0.69) and flexion peak torque (d=0.82). Effect sizes for galectin-3 (d=-0.31) (larger decrease) and interleukin-6 (d=0.38) (smaller increase) were small in the Curcumin C3 Complex® group compared to placebo. CONCLUSION: This pilot trial suggests that there were no difficulties with recruitment, adherence and safety specific to the study protocol. Preliminary findings warrant a Phase IIb clinical trial to test the effect of Curcumin C3 Complex® on physical function and muscle strength in older adults at risk for mobility disability.


Assuntos
Curcumina , Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Curcumina/farmacologia , Curcumina/uso terapêutico , Projetos Piloto , Força Muscular/fisiologia , Inflamação , Dieta
2.
AJNR Am J Neuroradiol ; 40(11): 1908-1915, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31649157

RESUMO

BACKGROUND AND PURPOSE: Ketogenic diets are being explored as a possible treatment for several neurological diseases, but the physiologic impact on the brain is unknown. The objective of this study was to evaluate the feasibility of 3T MR spectroscopy to monitor brain ketone levels in patients with high-grade gliomas who were on a ketogenic diet (a modified Atkins diet) for 8 weeks. MATERIALS AND METHODS: Paired pre- and post-ketogenic diet MR spectroscopy data from both the lesion and contralateral hemisphere were analyzed using LCModel software in 10 patients. RESULTS: At baseline, the ketone bodies acetone and ß-hydroxybutyrate were nearly undetectable, but by week 8, they increased in the lesion for both acetone (0.06 ± 0.03 ≥ 0.27 ± 0.06 IU, P = .005) and ß-hydroxybutyrate (0.07 ± 0.07 ≥ 0.79 ± 0.32 IU, P = .046). In the contralateral brain, acetone was also significantly increased (0.041 ± 0.01 ≥ 0.16 ± 0.04 IU, P = .004), but not ß-hydroxybutyrate. Acetone was detected in 9/10 patients at week 8, and ß-hydroxybutyrate, in 5/10. Acetone concentrations in the contralateral brain correlated strongly with higher urine ketones (r = 0.87, P = .001) and lower fasting glucose (r = -0.67, P = .03). Acetoacetate was largely undetectable. Small-but-statistically significant decreases in NAA were also observed in the contralateral hemisphere at 8 weeks. CONCLUSIONS: This study suggests that 3T MR spectroscopy is feasible for detecting small cerebral metabolic changes associated with a ketogenic diet, provided that appropriate methodology is used.


Assuntos
Neoplasias Encefálicas/dietoterapia , Encéfalo/metabolismo , Dieta Rica em Proteínas e Pobre em Carboidratos , Glioma/dietoterapia , Corpos Cetônicos/análise , Espectroscopia de Ressonância Magnética/métodos , Neoplasias Encefálicas/metabolismo , Feminino , Glioma/metabolismo , Humanos , Masculino
3.
J Frailty Aging ; 8(2): 72-78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30997919

RESUMO

BACKGROUND: Appendicular skeletal muscle mass index and muscle attenuation (density) are negatively associated with mortality in European-derived populations. OBJECTIVES: The present analyses assessed association between axial skeletal muscle density and muscle index with mortality in European Americans with type 2 diabetes mellitus (T2D). DESIGN: Single-center observational study. SETTING: Diabetes Heart Study. PARTICIPANTS: 839 European Americans with T2D. METHODS: Computed tomography-measured psoas and paraspinous muscle mass index (cross sectional area/height2) and radiographic density (Hounsfield Units) were assessed in all participants. A Cox proportional hazards model was computed. The fully-adjusted model included covariates age, sex, body mass index, smoking, alcohol use, diabetes duration, insulin use, hormone replacement therapy (women), prevalent cardiovascular disease (CVD), hypertension, and coronary artery calcified atherosclerotic plaque mass score. Deaths were recorded in the National Death Index data through December 31, 2015. RESULTS: Participants included 428 women and 411 men with median (25th, 75th quartile) age 62.8 (56.1, 69.1) years and diabetes duration 8.0 (5.0, 14.0) years. After 11.9 (9.4, 13.3) years of follow-up, 314 (37.4%) of participants were deceased. In the fully-adjusted model, psoas muscle density (hazard ratio [HR] 0.81, p<0.001), psoas muscle index (HR 0.82, p=0.008), and paraspinous muscle density (HR 0.85, p=0.003) were inversely associated with mortality. Paraspinous muscle index was not significantly associated with mortality (HR 0.90, p=0.08). Results did not differ significantly between men and women. CONCLUSIONS: In addition to established risk factors for mortality and CVD, higher psoas muscle index, psoas muscle density, and paraspinous muscle density were significantly associated with lower all-cause mortality in European Americans with T2D.


Assuntos
Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/mortalidade , Músculos Paraespinais/anatomia & histologia , Músculos Psoas/anatomia & histologia , População Branca/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Paraespinais/diagnóstico por imagem , Músculos Psoas/diagnóstico por imagem , Fatores de Risco , Tomografia Computadorizada por Raios X
4.
J Biomech ; 72: 23-28, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29503017

RESUMO

Area under the receiver operating characteristic curve (AROC) is commonly used to choose a biomechanical metric from which to construct an injury risk curve (IRC). However, AROC may not handle censored datasets adequately. Survival analysis creates robust estimates of IRCs which accommodate censored data. We present an observation-adjusted ROC (oaROC) which uses the survival-based IRC to estimate the AROC. We verified and evaluated this method using simulated datasets of different censoring statuses and sample sizes. For a dataset with 1000 left and right censored observations, the median AROC closely approached the oaROCTrue, or the oaROC calculated using an assumed "true" IRC, differing by a fraction of a percent, 0.1%. Using simulated datasets with various censoring, we found that oaROC converged onto oaROCTrue in all cases. For datasets with right and non-censored observations, AROC did not converge onto oaROCTrue. oaROC for datasets with only non-censored observations converged the fastest, and for a dataset with 10 observations, the median oaROC differed from oaROCTrue by 2.74% while the corresponding median AROC with left and right censored data differed from oaROCTrue by 9.74%. We also calculated the AROC and oaROC for a published side impact dataset, and differences between the two methods ranged between -24.08% and 24.55% depending on metric. Overall, when compared with AROC, we found oaROC performs equivalently for doubly censored data, better for non-censored data, and can accommodate more types of data than AROC. While more validation is needed, the results indicate that oaROC is a viable alternative which can be incorporated into the metric selection process for IRCs.


Assuntos
Medição de Risco , Ferimentos e Lesões , Área Sob a Curva , Humanos , Curva ROC , Análise de Sobrevida
5.
Oncogenesis ; 6(5): e326, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28459431

RESUMO

Epithelial ovarian cancer is the most lethal gynecological cancer mainly due to late diagnosis, easy spreading and rapid development of chemoresistance. Cancer stem cells are considered to be one of the main mechanisms for chemoresistance, as well as metastasis and recurrent disease. To explore the stemness characteristics of ovarian cancer stem cells, we successfully enriched ovarian cancer stem-like cells from an established ovarian cancer cell line (SKOV-I6) and a fresh ovarian tumor-derived cell line (OVS1). These ovarian cancer stem-like cells possess important cancer stemness characteristics including sphere-forming and self-renewing abilities, expressing important ovarian cancer stem cell and epithelial-mesenchymal transition markers, as well as increased drug resistance and potent tumorigenicity. Microarray analysis of OVS1-derived sphere cells revealed increased expression of amphiregulin (AREG) and decreased expression of its conserved regulatory microRNA, miR-34c-5p, when compared with the OVS1 parental cells. Overexpression of AREG and decreased miR-34c-5p expression in SKOV-I6 and OVS1 sphere cells were confirmed by quantitative real-time PCR analysis. Luciferase reporter assay and mutant analysis confirmed that AREG is a direct target of miR-34c-5p. Furthermore, AREG-mediated increase of sphere formation, drug resistance toward docetaxel and carboplatin, as well as tumorigenicity of SKOV-I6 and OVS1 cells could be abrogated by miR-34c-5p. We further demonstrated that miR-34c-5p inhibited ovarian cancer stemness through downregulation of the AREG-EGFR-ERK pathway. Overexpression of AREG was found to be correlated with advanced ovarian cancer stages and poor prognosis. Taken together, our data suggest that AREG promotes ovarian cancer stemness and drug resistance via the AREG-EGFR-ERK pathway and this is inhibited by miR-34c-5p. Targeting AREG, miR-34c-5p could be a potential strategy for anti-cancer-stem cell therapy in ovarian cancer.

6.
Artigo em Inglês | MEDLINE | ID: mdl-29745380

RESUMO

BACKGROUND: Because chronic kidney disease (CKD) is associated with muscle wasting, older adults with CKD are likely to have physical function deficits. Physical activity can improve these deficits, but whether CKD attenuates the benefits is unknown. Our objective was to determine if CKD modified the effect of a physical activity intervention in older adults. METHODS: This is an exploratory analysis of the LIFE-P study, which compared a 12-month physical activity program (PA) to a successful aging education program (SA) in older adults. CKD was defined as a baseline eGFR < 60 mL/min/1.73 m2. We examined the Short Physical Performance Battery (SPPB) at baseline, 6 and 12 months. Secondary outcomes included serious adverse events (SAE) and adherence to intervention frequency. Linear mixed models were adjusted for age, sex, diabetes, hypertension, CKD, intervention, site, visit, baseline SPPB, and interactions of intervention and visit and of intervention, visit, and baseline CKD. RESULTS: The sample included 368 participants. CKD was present in 105 (28.5%) participants with a mean eGFR of 49.2 ± 8.1 mL/min/1.73 m2. Mean SPPB was 7.38 ± 1.41 in CKD participants; 7.59 ± 1.44 in those without CKD (p = 0.20). For CKD participants in PA, 12-month SPPBs increased to 8.90 (95% CI 8.32, 9.47), while PA participants without CKD increased to 8.40 (95% CI 8.01, 8.79, p = 0.43). For CKD participants in SA, 12-month SPPBs increased to 7.67 (95% CI 7.07, 8.27), while participants without CKD increased to 8.12 (95% CI 7.72, 8.52, p = 0.86). Interaction between CKD and intervention was non-significant (p = 0.88). Number and type of SAEs were not different between CKD and non-CKD participants (all p > 0.05). In PA, adherence for CKD participants was 65.5 ± 25.4%, while for those without CKD was 74.0 ± 22.2% (p = 0.12). CONCLUSION: Despite lower adherence, older adults with CKD likely derive clinically meaningful benefits from physical activity with no apparent impact on safety, compared to those without CKD.

7.
Nutr Metab Cardiovasc Dis ; 26(10): 899-907, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27514606

RESUMO

BACKGROUND AND AIMS: Many US adults use calcium supplements to address inadequate dietary intake and improve bone health. However, recent reports have suggested that use of calcium supplements may elevate cardiovascular disease (CVD) risk. In this study, we examined associations between baseline calcium supplement use and incident myocardial infarction (MI) (n = 208 events) and CVD events (n = 641 events) over 10.3 years in men and women from the Multi-Ethnic Study of Atherosclerosis (MESA) cohort (n = 6236), with dietary calcium intake at baseline also examined as a supplementary objective. METHODS AND RESULTS: Using Cox proportional hazards models, no compelling associations between calcium intake from supplements or diet and incident CVD events were observed upon multivariate adjustment for potential confounders. An association with lower MI risk was observed comparing those with low levels of calcium supplement use (1-499 mg) to those using no calcium supplements (hazard ratio 0.69, 95% CI 0.48, 0.98, p = 0.039). Relationships were homogeneous by gender, race/ethnicity, or chronic kidney disease. Results were also similar when the analysis was limited to postmenopausal women only. CONCLUSION: Analysis of incident MI and CVD events in the MESA cohort does not support a substantial association of calcium supplement use with negative cardiovascular outcomes.


Assuntos
Cálcio/administração & dosagem , Doenças Cardiovasculares/epidemiologia , Suplementos Nutricionais , Idoso , Idoso de 80 Anos ou mais , Cálcio/efeitos adversos , Cálcio da Dieta/administração & dosagem , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/prevenção & controle , Estudos de Coortes , Suplementos Nutricionais/efeitos adversos , Feminino , Humanos , Incidência , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/epidemiologia , Pós-Menopausa , Modelos de Riscos Proporcionais , Fatores de Proteção , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
8.
J Frailty Aging ; 5(1): 6-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26980363

RESUMO

BACKGROUND: Converging evidence suggests that physical activity is an effective intervention for both clinical depression and sub-threshold depressive symptoms; however, findings are not always consistent. These mixed results might reflect heterogeneity in response to physical activity, with some subgroups of individuals responding positively, but not others. OBJECTIVES: 1) To examine the impact of genetic variation and sex on changes in depressive symptoms in older adults after a physical activity (PA) intervention, and 2) to determine if PA differentially improves particular symptom dimensions of depression. DESIGN: Randomized controlled trial. SETTING: Four field centers (Cooper Institute, Stanford University, University of Pittsburgh, and Wake Forest University). PARTICIPANTS: 396 community-dwelling adults aged 70-89 years who participated in the Lifestyle Interventions and Independence for Elders Pilot Study (LIFE-P). INTERVENTION: 12-month PA intervention compared to an education control. MEASUREMENTS: Polymorphisms in the serotonin transporter (5-HTT), brain-derived neurotrophic factor (BDNF), and apolipoprotein E (APOE) genes; 12-month change in the Center for Epidemiologic Studies Depression Scale total score, as well as scores on the depressed affect, somatic symptoms, and lack of positive affect subscales. RESULTS: Men randomized to the PA arm showed the greatest decreases in somatic symptoms, with a preferential benefit in male carriers of the BDNF Met allele. Symptoms of lack of positive affect decreased more in men compared to women, particularly in those possessing the 5-HTT L allele, but the effect did not differ by intervention arm. APOE status did not affect change in depressive symptoms. CONCLUSIONS: Results of this study suggest that the impact of PA on depressive symptoms varies by genotype and sex, and that PA may mitigate somatic symptoms of depression more than other symptoms. The results suggest that a targeted approach to recommending PA therapy for treatment of depression is viable.


Assuntos
Apolipoproteínas E/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão , Terapia por Exercício/métodos , Estilo de Vida , Atividade Motora , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Idoso , Idoso de 80 Anos ou mais , Depressão/diagnóstico , Depressão/genética , Depressão/fisiopatologia , Depressão/terapia , Feminino , Humanos , Vida Independente/psicologia , Masculino , Atividade Motora/genética , Atividade Motora/fisiologia , Polimorfismo Genético , Escalas de Graduação Psiquiátrica , Fatores Sexuais , Resultado do Tratamento
9.
Osteoarthritis Cartilage ; 24(6): 991-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26774734

RESUMO

OBJECTIVE: Unicompartmental knee arthroplasty (UKA) revision is usually due to the degenerative degree of knee articular osteochondral tissue in the untreated compartment. However, it is difficult to simulate the biomechanical behavior on this tissue accurately. This study presents and validates a reliable system to predict which osteoarthritis (OA) patients may suffer revision as a result of biomechanical reasons after having UKA. DESIGN: We collected all revision cases available (n = 11) and randomly selected 67 UKA cases to keep the revision prevalence of almost 14%. All these 78 cases have been followed at least 2 years. An elastic model is designed to characterize the biomechanical behavior of the articular osteochondral tissue for each patient. After calculated the force on the tissue, finite element method (FEM) is applied to calculating the strain of each tissue node. Kernel Ridge Regression (KRR) method is used to model the relationship between the strain information and the risk of revision. Therefore, the risk of UKA revision can be predicted by this integrated model. RESULTS: Leave-one-out (LOO) cross-validation (CV) is implemented to assess the prediction accuracy. As a result, the mean prediction accuracy is 93.58% for all these cases, demonstrating the high value of this model as a decision-making assistant for surgical plaining of knee OA. CONCLUSIONS: The results of this study demonstrated that this integrated model can predict the risk of UKA revision with theoretically high accuracy. It combines bio-mechanical and statistical learning approach to create a surgical planning tool which may support clinical decision in the future.


Assuntos
Artroplastia do Joelho , Humanos , Articulação do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Reoperação , Risco , Resultado do Tratamento
10.
Diabetes Obes Metab ; 18(1): 92-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26435375

RESUMO

The aim of this study was to identify the clinical features of participants in the standard therapy arm of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) glycaemia trial who failed to reach the glycated haemoglobin (HbA1c) target. We analysed 4685 participants in the standard therapy arm, comparing participants who reached the HbA1c target of <8.0% with those whose HbA1c level was ≥8.0% 12 months after randomization. Baseline and 12-month clinical characteristics were compared. At 12 months after randomization, 3194 participants had HbA1c <8.0% and 1491 had HbA1c ≥8.0%. Black race [odds ratio (OR) 0.74, 95% confidence interval (CI) 0.61-0.89; p = 0.002], severe hypoglycaemia (OR 0.57, CI 0.37-0.89; p = 0.014) and insulin use (OR 0.51, CI 0.40-0.65; p < 0.001) were associated with failure to reach HbA1c goal at 12 months in the adjusted model. Even with free medications, free visits with clinicians and aggressive titration of medications, >30% of participants in the standard arm of the ACCORD trial had an HbA1c ≥8.0% at 1 year. Participants who were black, had severe hypoglycaemia and were on insulin were more likely to have an above-target HbA1c concentration after 12 months on the standard protocol.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/sangue , Hemoglobinas Glicadas/análise , Hipoglicemiantes/uso terapêutico , Idoso , População Negra/estatística & dados numéricos , Glicemia/análise , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/etnologia , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Insulina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores de Risco , Falha de Tratamento
11.
J Nutr Health Aging ; 19(9): 922-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26482694

RESUMO

OBJECTIVES: C-terminal Agrin Fragment (CAF) has been proposed as a potential circulating biomarker for predicting changes in physical function among older adults. To determine the effect of a one-year PA intervention on changes in CAF concentrations and to evaluate baseline and longitudinal associations between CAF concentrations and indices of physical function. DESIGN: Ancillary study to the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P), a multi-site randomized clinical trial designed to evaluate the effects of chronic exercise on the physical function of older adults at risk for mobility disability. SETTING: Four academic research centers within the U.S. PARTICIPANTS: Three hundred thirty three older adults aged 70 to 89 with mild to moderate impairments in physical function. INTERVENTION: A 12-month intervention of either structured physical activity (PA) or health education promoting successful aging (SA). MEASUREMENTS: Serum CAF concentrations and objectives measures of physical function - i.e. gait speed and performance on the Short Physical Performance Battery (SPPB). RESULTS: The group*time interaction was not significant for serum CAF concentrations (p=0.265), indicating that the PA intervention did not significantly reduce serum CAF levels compared to SA. Baseline gait speed was significantly correlated with baseline CAF level (r = -0.151, p= 0.006), however the association between CAF and SPPB was not significant. Additionally, neither baseline nor the change in CAF concentrations strongly predicted the change in either performance measure following the PA intervention. CONCLUSION: In summary, the present study shows that a one-year structured PA program did not reduce serum CAF levels among mobility-limited older adults. However, further study is needed to definitively determine the utility of CAF as a biomarker of physical function.


Assuntos
Agrina/sangue , Exercício Físico , Marcha , Limitação da Mobilidade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Biomarcadores/sangue , Feminino , Avaliação Geriátrica , Humanos , Estilo de Vida , Masculino , Aptidão Física , Estados Unidos
12.
Mol Cell Neurosci ; 65: 31-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25701814

RESUMO

Activation of AMPA receptors assembled with the GluA1 subunit can promote dendrite growth in a manner that depends on its direct binding partner, SAP97. SAP97 is a modular scaffolding protein that has at least seven recognizable protein-protein interaction domains. Several complementary approaches were employed to show that the dendrite branching promoting action of full length SAP97 depends on ligand(s) that bind to the PDZ3 domain. Ligand(s) to PDZ1, PDZ2 and I3 domains also contribute to dendrite growth. The ability of PDZ3 ligand(s) to promote dendrite growth depends on localization at the plasma membrane along with GluA1 and SAP97. These results suggest that the assembly of a multi-protein complex at or near synapses is vital for the translation of AMPA-R activity into dendrite growth.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Dendritos/metabolismo , Proteínas de Membrana/metabolismo , Neurogênese , Domínios PDZ , Proteínas Adaptadoras de Transdução de Sinal/química , Animais , Células Cultivadas , Células HEK293 , Humanos , Proteínas de Membrana/química , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Medula Espinal/citologia , Medula Espinal/metabolismo
13.
Osteoarthritis Cartilage ; 23(3): 370-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25528106

RESUMO

BACKGROUND: Vitamin K-dependent (VKD) proteins, including the mineralization inhibitor matrix-gla protein (MGP), are found in joint tissues including cartilage and bone. Previous studies suggest low vitamin K status is associated with higher osteoarthritis (OA) prevalence and incidence. OBJECTIVE: To clarify what joint tissues vitamin K is relevant to in OA, we investigated the cross-sectional and longitudinal association between vitamin K status and knee OA structural features measured using magnetic resonance imaging (MRI). METHODS: Plasma phylloquinone (PK, vitamin K1) and dephosphorylated-uncarboxylated MGP ((dp)ucMGP) were measured in 791 older community-dwelling adults who had bilateral knee MRIs (mean ± SD age = 74 ± 3 y; 67% female). The adjusted odds ratios (and 95% confidence intervals) [OR (95%CI)] for presence and progression of knee OA features according to vitamin K status were calculated using marginal models with generalized estimating equations (GEEs), adjusted for age, sex, body mass index (BMI), triglycerides and other pertinent confounders. RESULTS: Longitudinally, participants with very low plasma PK (<0.2 nM) were more likely to have articular cartilage and meniscus damage progression after 3 years [OR (95% CIs): 1.7(1.0-3.0), 2.6(1.3-5.2) respectively] compared to sufficient PK (≥ 1.0 nM). Higher plasma (dp)ucMGP (reflective of lower vitamin K status) was associated with higher odds of meniscus damage, osteophytes, bone marrow lesions, and subarticular cysts cross-sectionally [ORs (95% CIs) comparing highest to lowest quartile: 1.6(1.1-2.3); 1.7(1.1-2.5); 1.9(1.3-2.8); 1.5(1.0-2.1), respectively]. CONCLUSION: Community-dwelling men and women with very low plasma PK were more likely to have progression of articular cartilage and meniscus damage. Plasma (dp)ucMGP was associated with presence of knee OA features but not progression. Future studies are needed to clarify mechanisms underlying vitamin Ks role in OA.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cartilagem Articular/patologia , Proteínas da Matriz Extracelular/metabolismo , Meniscos Tibiais/patologia , Osteoartrite do Joelho/metabolismo , Vitamina K 1/metabolismo , Deficiência de Vitamina K/metabolismo , Idoso , Estudos de Coortes , Estudos Transversais , Descarboxilação , Progressão da Doença , Feminino , Humanos , Incidência , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Razão de Chances , Osteoartrite do Joelho/epidemiologia , Osteoartrite do Joelho/patologia , Osteófito/epidemiologia , Osteófito/metabolismo , Osteófito/patologia , Fosforilação , Deficiência de Vitamina K/epidemiologia , Proteína de Matriz Gla
14.
J Nutr Health Aging ; 18(1): 59-64, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24402391

RESUMO

OBJECTIVE: To determine if sarcopenia modulates the response to a physical activity intervention in functionally limited older adults. DESIGN: Secondary analysis of a randomized controlled trial. SETTING: Three academic centers. PARTICIPANTS: Elders aged 70 to 89 years at risk for mobility disability who underwent dual-energy x-ray absorptiometry (DXA) for body composition at enrollment and follow-up at twelve months (N = 177). INTERVENTION: Subjects participated in a physical activity program (PA) featuring aerobic, strength, balance, and flexibility training, or a successful aging (SA) educational program about healthy aging. MEASUREMENTS: Sarcopenia as determined by measuring appendicular lean mass and adjusting for height and total body fat mass (residuals method), Short Physical Performance Battery score (SPPB), and gait speed determined on 400 meter course. RESULTS: At twelve months, sarcopenic and non-sarcopenic subjects in PA tended to have higher mean SPPB scores (8.7±0.5 and 8.7±0.2 points) compared to sarcopenic and non-sarcopenic subjects in SA (8.3±0.5 and 8.4±0.2 points, p = 0.24 and 0.10), although the differences were not statistically significant. At twelve months, faster mean gait speeds were observed in PA: 0.93±0.4 and 0.95±0.03 meters/second in sarcopenic and non-sarcopenic PA subjects, and 0.89±0.4 and 0.91±0.03 meters/second in sarcopenic and non-sarcopenic SA subjects (p = 0.98 and 0.26), although not statistically significant. There was no difference between the sarcopenic and non-sarcopenic groups in intervention adherence or number of adverse events. CONCLUSION: These data suggest that older adults with sarcopenia, who represent a vulnerable segment of the elder population, are capable of improvements in physical performance after a physical activity intervention.


Assuntos
Exercício Físico/fisiologia , Marcha , Estilo de Vida , Limitação da Mobilidade , Aptidão Física/fisiologia , Sarcopenia/terapia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Composição Corporal , Feminino , Avaliação Geriátrica , Humanos , Vida Independente , Masculino , Projetos Piloto , Sarcopenia/complicações , Sarcopenia/fisiopatologia
15.
Pharmacogenomics J ; 14(4): 309-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24394200

RESUMO

In a common pharmacogenomic scenario, outcome measures are compared for treated and untreated subjects across genotype-defined subgroups. The key question is whether treatment benefit (or harm) is particularly strong in certain subgroups, and therefore the statistical analysis focuses on the interaction between treatment and genotype. However, genome-wide analysis in such scenarios requires careful statistical thought as, in addition to the usual problems of multiple testing, the marker-defined sample sizes, and therefore power, vary across the individual genotypes being evaluated. The variability in power means that the usual practice of using a common P-value threshold across tests has difficulties. The reason is that the use of a fixed threshold, with variable power, implies that the costs of type I and type II errors vary across tests in a manner that is implicit rather than dictated by the analyst. In this paper we discuss this problem and describe an easily implementable solution based on Bayes factors. We pay particular attention to the specification of priors, which is not a straightforward task. The methods are illustrated using data from a randomized controlled clinical trial in which homocysteine levels are compared in individuals receiving low and high doses of folate supplements and across marker subgroups. The method we describe is implemented in the R computing environment with code available from http://faculty.washington.edu/jonno/cv.html.


Assuntos
Estudo de Associação Genômica Ampla , Farmacogenética , Teorema de Bayes , Humanos , Polimorfismo de Nucleotídeo Único , Probabilidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/prevenção & controle , Vitaminas/administração & dosagem
16.
Neurology ; 77(16): 1543-50, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-21975197

RESUMO

OBJECTIVES: The Vitamin Intervention for Stroke Prevention trial found an association between baseline poststroke homocysteine (Hcy) and recurrent stroke. We investigated genes for enzymes and cofactors in the Hcy metabolic pathway for association with Hcy and determined whether associated single nucleotide polymorphisms (SNPs) influenced recurrent stroke risk. METHODS: Eighty-six SNPs in 9 candidate genes (BHMT1, BHMT2, CBS, CTH, MTHFR, MTR, MTRR, TCN1, and TCN2) were genotyped in 2,206 subjects (83% European American). Associations with Hcy measures were assessed using linear regression models assuming an additive genetic model, adjusting for age, sex, and race and additionally for baseline Hcy when postmethionine load change was assessed. Associations with recurrent stroke were evaluated using survival analyses. RESULTS: Five SNPs in the transcobalamin 2 (TCN2) gene were associated with baseline Hcy (false discovery rate [FDR]-adjusted p = 0.049). TCN2 SNP rs731991 was associated with recurrent stroke risk in the low-dose arm of the trial under a recessive model (log-rank test p = 0.009, hazard ratio 0.34). Associations with change in postmethionine load Hcy levels were found with 5 SNPs in the cystathionine ß-synthase (CBS) gene (FDR-adjusted p < 0.031). CONCLUSIONS: TCN2 variants contribute to poststroke Hcy levels, whereas variants in the CBS gene influence Hcy metabolism. Variation in the TCN2 gene also affects recurrent stroke risk in response to cofactor therapy.


Assuntos
Homocisteína/sangue , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/genética , Transcobalaminas/genética , Adulto , Idoso , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade
17.
Nutr Metab Cardiovasc Dis ; 21(5): 332-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20153618

RESUMO

BACKGROUND AND AIMS: Arterial stiffness is a prominent feature of vascular aging and a risk factor for cardiovascular disease (CVD). Fat around the heart and blood vessels (i.e. pericardial fat, Pfat) may contribute to arterial stiffness via a local paracrine effect of adipose tissue on the surrounding vasculature. Thus, we determined the association between Pfat and carotid stiffness in 5770 participants (mean age 62 years, 53% female, 25% African American, 24% Hispanic, and 13% Chinese) from the Multi-Ethnic Study of Atherosclerosis. METHODS AND RESULTS: Pfat was measured by computed tomography, and ultrasonography of the common carotid artery was used to calculate the distensibility coefficient (DC) and Young's modulus (YM). Lower DC and higher YM values indicate stiffer arteries. Pfat quartile was highly associated with demographic, behavioral, anthropometric, hemodynamic, metabolic, and disease variables in both men and women. After adjusting for height, clinical site, CVD risk factors, and medications, a 1 standard deviation (41.91 cm(3)) increment in Pfat was associated with a 0.00007±0.00002 1/mm Hg lower DC (p=0.0002) in men and a 48.1±15.1 mm Hg/mm higher YM in women (p=0.002). Additional adjustment for C-reactive protein, coronary artery calcification, and carotid intima-media thickness had only modest effects. More importantly, adjusting for body mass index and waist circumference did not significantly change the overall results. CONCLUSION: Higher Pfat is associated with higher carotid stiffness, independent of traditional CVD risk factors and obesity.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Aterosclerose/etnologia , Artéria Carótida Primitiva/patologia , Etnicidade , Pericárdio/diagnóstico por imagem , Tecido Adiposo/fisiopatologia , Idoso , Aterosclerose/complicações , Aterosclerose/diagnóstico , Aterosclerose/diagnóstico por imagem , Composição Corporal , Proteína C-Reativa/metabolismo , Artéria Carótida Primitiva/diagnóstico por imagem , Doença da Artéria Coronariana/etnologia , Módulo de Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/complicações , Obesidade/diagnóstico por imagem , Estudos Prospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X , Circunferência da Cintura
18.
Neuroscience ; 171(4): 1075-90, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20923697

RESUMO

The vulnerability of brain neuronal cell subpopulations to neurologic insults varies greatly. Among cells that survive a pathological insult, for example ischemia or brain trauma, some may undergo morphological and/or biochemical changes that may compromise brain function. The present study is a follow-up of our previous studies that investigated the effect of glutamate-induced excitotoxicity on the GABA synthesizing enzyme glutamic acid decarboxylase (GAD65/67)'s expression in surviving DIV 11 cortical GABAergic neurons in vitro [Monnerie and Le Roux, (2007) Exp Neurol 205:367-382, (2008) Exp Neurol 213:145-153]. An N-methyl-D-aspartate receptor (NMDAR)-mediated decrease in GAD expression was found following glutamate exposure. Here we examined which NMDAR subtype(s) mediated the glutamate-induced change in GAD protein levels. Western blotting techniques on cortical neuron cultures showed that glutamate's effect on GAD proteins was not altered by NR2B-containing diheteromeric (NR1/NR2B) receptor blockade. By contrast, blockade of triheteromeric (NR1/NR2A/NR2B) receptors fully protected against a decrease in GAD protein levels following glutamate exposure. When receptor location on the postsynaptic membrane was examined, extrasynaptic NMDAR stimulation was observed to be sufficient to decrease GAD protein levels similar to that observed after glutamate bath application. Blocking diheteromeric receptors prevented glutamate's effect on GAD proteins after extrasynaptic NMDAR stimulation. Finally, NR2B subunit examination with site-specific antibodies demonstrated a glutamate-induced, calpain-mediated alteration in NR2B expression. These results suggest that glutamate-induced excitotoxic NMDAR stimulation in cultured GABAergic cortical neurons depends upon subunit composition and receptor location (synaptic vs. extrasynaptic) on the neuronal membrane. Biochemical alterations in surviving cortical GABAergic neurons in various disease states may contribute to the altered balance between excitation and inhibition that is often observed after injury.


Assuntos
Córtex Cerebral/citologia , Glutamato Descarboxilase/metabolismo , Ácido Glutâmico/farmacologia , Neurônios/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/fisiologia , Ácido gama-Aminobutírico/metabolismo , Análise de Variância , Animais , Bicuculina/farmacologia , Calpaína/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Interações Medicamentosas , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , GABAérgicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glicinérgicos/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Patch-Clamp/métodos , Estricnina/farmacologia
19.
Water Sci Technol ; 61(2): 317-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20107257

RESUMO

Human enteric viruses are important agents of waterborne illness. They are diffusely distributed in environmental waters, necessitating concentration of tens to hundreds of litres for effective detection. This study evaluates the novel ViroCap disposable capsule filter for concentration of coliphage MS2 and poliovirus (PV1) from deionised (DI) water and artificial seawater, as well as natural ground, surface, and seawater. Retention and recoveries for the ViroCap were compared with two well-characterised filters: the 1MDS for DI water, and the OptiCap XL for artificial seawater. The mean adsorption for MS2 by the ViroCap was 88%. Recovery of MS2 was significantly greater (p< or=0.01) than alternative filters tested: 65% from DI water and 63% from artificial seawater, compared to 30% for the 1MDS and 15% for the OptiCap for the respective matrices. Recovery of PV1 from DI water (37%) was similar to that of the 1MDS (51%). PV1 recoveries from artificial seawater were significantly greater (p< or =0.01) for the ViroCap (44%) than the OptiCap (11%). Recovery of MS2 from seeded environmental samples yielded 44% from groundwater, 53% from surface water, and 51% from seawater. ViroCap disposable filter is efficient for concentrating MS2 and PV1 from diverse matrices and is robust across a range of ionic concentrations.


Assuntos
Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Microbiologia da Água , Purificação da Água/instrumentação , Purificação da Água/métodos
20.
Phys Rev Lett ; 103(11): 117002, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19792394

RESUMO

Superconductivity was recently found in the tetragonal phase FeSe. A structural transformation from tetragonal to orthorhombic (or monoclinic, depending on point of view) was observed at low temperature, but was not accompanied by a magnetic ordering as commonly occurs in the parent compounds of FeAs-based superconductors. Here, we report the correlation between structural distortion and superconductivity in FeSe(1-x) thin films with different preferred growth orientations. The films with preferred growth along the c axis show a strong thickness dependent suppression of superconductivity and low temperature structural distortion. In contrast, both properties are less affected in the films with (101) preferred orientation. These results suggest that the low temperature structural distortion is closely associated with the superconductivity of this material.

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