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2.
Nat Aging ; 3(3): 248-257, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37118425

RESUMEN

The geroscience hypothesis proposes that therapy to slow or reverse molecular changes that occur with aging can delay or prevent multiple chronic diseases and extend healthy lifespan1-3. Caloric restriction (CR), defined as lessening caloric intake without depriving essential nutrients4, results in changes in molecular processes that have been associated with aging, including DNA methylation (DNAm)5-7, and is established to increase healthy lifespan in multiple species8,9. Here we report the results of a post hoc analysis of the influence of CR on DNAm measures of aging in blood samples from the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) trial, a randomized controlled trial in which n = 220 adults without obesity were randomized to 25% CR or ad libitum control diet for 2 yr (ref. 10). We found that CALERIE intervention slowed the pace of aging, as measured by the DunedinPACE DNAm algorithm, but did not lead to significant changes in biological age estimates measured by various DNAm clocks including PhenoAge and GrimAge. Treatment effect sizes were small. Nevertheless, modest slowing of the pace of aging can have profound effects on population health11-13. The finding that CR modified DunedinPACE in a randomized controlled trial supports the geroscience hypothesis, building on evidence from small and uncontrolled studies14-16 and contrasting with reports that biological aging may not be modifiable17. Ultimately, a conclusive test of the geroscience hypothesis will require trials with long-term follow-up to establish effects of intervention on primary healthy-aging endpoints, including incidence of chronic disease and mortality18-20.


Asunto(s)
Restricción Calórica , Metilación de ADN , Humanos , Adulto , Restricción Calórica/métodos , Ingestión de Energía , Envejecimiento/genética , Longevidad
3.
Osteoarthritis Cartilage ; 31(7): 954-965, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36893979

RESUMEN

OBJECTIVE: To develop sets of core and optional recommended domains for describing and evaluating Osteoarthritis Management Programs (OAMPs), with a focus on hip and knee Osteoarthritis (OA). DESIGN: We conducted a 3-round modified Delphi survey involving an international group of researchers, health professionals, health administrators and people with OA. In Round 1, participants ranked the importance of 75 outcome and descriptive domains in five categories: patient impacts, implementation outcomes, and characteristics of the OAMP and its participants and clinicians. Domains ranked as "important" or "essential" by ≥80% of participants were retained, and participants could suggest additional domains. In Round 2, participants rated their level of agreement that each domain was essential for evaluating OAMPs: 0 = strongly disagree to 10 = strongly agree. A domain was retained if ≥80% rated it ≥6. In Round 3, participants rated remaining domains using same scale as in Round 2; a domain was recommended as "core" if ≥80% of participants rated it ≥9 and as "optional" if ≥80% rated it ≥7. RESULTS: A total of 178 individuals from 26 countries participated; 85 completed all survey rounds. Only one domain, "ability to participate in daily activities", met criteria for a core domain; 25 domains met criteria for an optional recommendation: 8 Patient Impacts, 5 Implementation Outcomes, 5 Participant Characteristics, 3 OAMP Characteristics and 4 Clinician Characteristics. CONCLUSION: The ability of patients with OA to participate in daily activities should be evaluated in all OAMPs. Teams evaluating OAMPs should consider including domains from the optional recommended set, with representation from all five categories and based on stakeholder priorities in their local context.


Asunto(s)
Osteoartritis de la Cadera , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/terapia , Osteoartritis de la Cadera/terapia , Consenso , Personal de Salud , Encuestas y Cuestionarios , Técnica Delphi
4.
Osteoarthritis Cartilage ; 26(3): 383-396, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29307722

RESUMEN

OBJECTIVE: To compare the effectiveness of physical therapy (PT, evidence-based approach) and internet-based exercise training (IBET), each vs a wait list (WL) control, among individuals with knee osteoarthritis (OA). DESIGN: Randomized controlled trial of 350 participants with symptomatic knee OA, allocated to standard PT, IBET and WL control in a 2:2:1 ratio, respectively. The PT group received up to eight individual visits within 4 months. The IBET program provided tailored exercises, video demonstrations, and guidance on progression. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC, range 0 [no problems]-96 [extreme problems]), assessed at baseline, 4 months (primary time point) and 12 months. General linear mixed effects modeling compared changes in WOMAC among study groups, with superiority hypotheses testing differences between each intervention group and WL and non-inferiority hypotheses comparing IBET with PT. RESULTS: At 4-months, improvements in WOMAC score did not differ significantly for either the IBET or PT group compared with WL (IBET: -2.70, 95% Confidence Interval (CI) = -6.24, 0.85, P = 0.14; PT: -3.36, 95% (CI) = -6.84, 0.12, P = 0.06). Similarly, at 12-months mean differences compared to WL were not statistically significant for either group (IBET: -2.63, 95% CI = -6.37, 1.11, P = 0.17; PT: -1.59, 95% CI = -5.26, 2.08, P = 0.39). IBET was non-inferior to PT at both time points. CONCLUSIONS: Improvements in WOMAC score following IBET and PT did not differ significantly from the WL group. Additional research is needed to examine strategies for maximizing benefits of exercise-based interventions for patients with knee OA. TRIAL REGISTRATION: NCT02312713.


Asunto(s)
Ejercicio Físico , Osteoartritis de la Rodilla/terapia , Modalidades de Fisioterapia , Anciano , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
5.
Diabet Med ; 32(8): 1090-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25818859

RESUMEN

AIM: To investigate whether previous physical activity levels are associated with blood glucose levels in individuals with impaired glucose tolerance in the context of an international pharmaceutical trial. METHODS: Data were analysed from the NAVIGATOR trial, which involved 9306 individuals with impaired glucose tolerance and high cardiovascular risk from 40 different countries, recruited in the period 2002-2004. Fasting glucose, 2-h post-challenge glucose and physical activity (pedometer) were assessed annually. A longitudinal regression analysis was used to determine whether physical activity levels 2 years (t-2 ) and 1 year (t-1 ) previously were associated with levels of glucose, after adjusting for previous glucose levels and other patient characteristics. Those participants with four consecutive annual measures of glucose and two consecutive measures of physical activity were included in the analysis. RESULTS: The analysis included 3964 individuals. Change in physical activity from t-2 to t-1 and activity levels at t-2 were both associated with 2-h glucose levels after adjustment for previous glucose levels and baseline characteristics; however, the associations were weak: a 100% increase in physical activity was associated with a 0.9% reduction in 2-h glucose levels. In addition, previous physical activity only explained an additional 0.05% of the variance in 2-h glucose over the variance explained by the history of 2-h glucose alone (R(2)  = 0.3473 vs. 0.3468). There was no association with fasting glucose. CONCLUSIONS: In the context of a large international clinical trial, previous physical activity levels did not meaningfully influence glucose levels in those with a high risk of chronic disease, after taking into account participants' previous trajectory of glucose control.


Asunto(s)
Glucemia/metabolismo , Ayuno , Intolerancia a la Glucosa/metabolismo , Actividad Motora , Conducta de Reducción del Riesgo , Acelerometría , Actigrafía , Anciano , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Enfermedades Cardiovasculares , Estudios de Cohortes , Ciclohexanos/uso terapéutico , Femenino , Intolerancia a la Glucosa/tratamiento farmacológico , Prueba de Tolerancia a la Glucosa , Humanos , Hipoglucemiantes/uso terapéutico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Nateglinida , Fenilalanina/análogos & derivados , Fenilalanina/uso terapéutico , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Valsartán/uso terapéutico
6.
Scand J Rheumatol ; 44(2): 106-10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25222824

RESUMEN

OBJECTIVES: Until recently, reports of physical activity in rheumatoid arthritis (RA) were limited to self-report methods and/or leisure-time physical activity. Our objectives were to assess, determine correlates of, and compare to well-matched controls both exercise and sedentary time in a typical clinical cohort of RA. METHOD: Persons with established RA (seropositive or radiographic erosions; n = 41) without diabetes or cardiovascular disease underwent assessments of traditional and disease-specific correlates of physical activity and 7 days of triaxial accelerometry. Twenty-seven age, gender, and body mass index (BMI)-matched controls were assessed. RESULTS: For persons with RA, objectively measured median (25th-75th percentile) exercise time was 3 (1-11) min/day; only 10% (n = 4) of participants exercised for ≥ 30 min/day. Time spent in sedentary activities was 92% (89-95%). Exercise time was not related to pain but was inversely related to disease activity (r = -0.3, p < 0.05) and disability (r = -0.3, p < 0.05) and positively related to self-efficacy for endurance activity (r = 0.4, p < 0.05). Sedentary activity was related only to self-efficacy for endurance activity (r = -0.4, p < 0.05). When compared to matched controls, persons with RA exhibited poorer self-efficacy for physical activity but similar amounts of exercise and sedentary time. CONCLUSIONS: For persons with RA and without diabetes or cardiovascular disease, time spent in exercise was well below established guidelines and activity patterns were predominantly sedentary. For optimal care in RA, in addition to promoting exercise, clinicians should consider assessing sedentary behaviour and self-efficacy for exercise. Future interventions might determine whether increased self-efficacy can increase physical activity in RA.


Asunto(s)
Artritis Reumatoide/fisiopatología , Actividad Motora/fisiología , Conducta Sedentaria , Autoeficacia , Acelerometría , Anciano , Índice de Masa Corporal , Estudios de Casos y Controles , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Factores de Tiempo
7.
Poult Sci ; 91(12): 3178-83, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23155028

RESUMEN

Genetic selection has been very successful at significantly increasing BW and breast muscle proportion in commercial broiler and turkey strains. The mechanisms of breast muscle growth in poultry and the interactive effects of nutritional status and selection are not fully understood. The hypothesis underlying the current study is that feed restriction, simply as a vehicle for controlling early growth, would delay the temporal expression pattern of neonatal (nMyHC) and adult (aMyHC) fast skeletal muscle myosin heavy chain (MyHC) isoforms in the pectoralis major muscle of turkey poults. The poultry growth model used to evaluate this hypothesis consisted of a randombred control turkey line (RBC2) that represents commercial turkeys of the 1960s and a line developed from the RBC2 by selection for BW at 16 wk of age (F line). The F line has significantly heavier breast muscles than the RBC2 concomitant with increased BW, but the proportion of breast muscle relative to BW is similar. A quantitative indirect ELISA using fast skeletal MyHC isoform specific monoclonal antibodies revealed no significant line differences in the temporal expression of posthatch fast skeletal muscle MyHC in ad libitum fed poults. Feed restriction, however, altered the temporal expression patterns of nMyHC and aMyHC in both F line and RBC2 poults compared with the poults fed ad libitum.


Asunto(s)
Privación de Alimentos/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Fibras Musculares de Contracción Rápida/metabolismo , Miosinas del Músculo Esquelético/metabolismo , Pavos/crecimiento & desarrollo , Pavos/genética , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Miosinas del Músculo Esquelético/genética , Pavos/metabolismo
9.
Int J Sports Med ; 33(3): 218-23, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22261824

RESUMEN

Exercise increases peak VO2 partially through muscle adaptations. However, understanding muscle adaptations related to exercise dose is incomplete. This study investigated exercise training dose on capillaries per fiber and capillaries per area; and citrate synthase from vastus lateralis and related both to changes in peak VO2. This randomized trial compared 3 exercise doses: low amount-moderate intensity (n=40), low amount-high intensity (n=47), high amount-high intensity (n=41), and a control group (n=35). Both measures of capillary supply increased in all exercise groups (p<0.05). Low amount-high intensity and high amount-high intensity improved citrate synthase (p<0.05) and the low amount-moderate intensity citrate synthase approached significance (p=0.059). Muscle improvements were only related to improvements in peak VO2 in high amount-high intensity (citrate synthase, r=0.304; capillaries:fiber, r= - 0.318; p<0.05 and capillaries/mm2 r= - 0.310, p<0.05). These data suggest muscle adaptations occur following both low and high exercise doses, but are only related to improved peak VO2 following high amount-high intensity training.


Asunto(s)
Citrato (si)-Sintasa/metabolismo , Ejercicio Físico/fisiología , Músculo Esquelético/metabolismo , Consumo de Oxígeno/fisiología , Adulto , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Scand J Rheumatol ; 39(5): 380-6, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20604671

RESUMEN

OBJECTIVES: The primary aim was to explore whether arthritis is associated with poorer self-efficacy and motivation for, and participation in, two specific types of physical activity (PA): endurance training (ET) and strength training (ST). A further objective was to determine whether the added burden of diabetes contributes to a further reduction in these PA determinants and types. METHODS: Self-efficacy and motivation for exercise and minutes per week of ET and ST were measured in 347 older veterans enrolled in a home-based PA counselling intervention. Regression analyses were used to compare high versus low self-efficacy and motivation and PA minutes in persons without arthritis, with arthritis alone, and with arthritis plus diabetes. RESULTS: Persons with arthritis alone reported lower self-efficacy for ET and ST than those without arthritis [odds ratio (OR)ET 0.71, 95% confidence interval (CI) 0.39­1.20; ORST 0.69, 95% CI 0.39­1.20]. A further reduction in self-efficacy for these two types of PA was observed for those with both arthritis and diabetes (ORET 0.65, 95% CI 0.44­0.92; ORST 0.64, 95% CI 0.44­0.93; trend p < 0.001). There was no trend towards a reduction in motivation for PA in those with arthritis alone or with arthritis and diabetes. Persons with arthritis exhibited higher motivation for ET than those without arthritis (ORET 1.85, 95% CI 1.12­3.33). There were no significant differences between the three groups in minutes of ET (p = 0.93), but persons with arthritis plus diabetes reported significantly less ST compared to individuals with arthritis only (p = 0.03). CONCLUSIONS: Despite reduced self-efficacy for ET and ST and less ST in older persons with arthritis, motivation for both PA types remains high, even in the presence of diabetes.


Asunto(s)
Artritis/psicología , Diabetes Mellitus/psicología , Motivación , Actividad Motora , Participación del Paciente/psicología , Autoimagen , Factores de Edad , Anciano , Anciano de 80 o más Años , Artritis/epidemiología , Artritis/fisiopatología , Cognición , Comorbilidad , Estudios Transversales , Diabetes Mellitus/epidemiología , Diabetes Mellitus/fisiopatología , Femenino , Encuestas Epidemiológicas , Humanos , Estilo de Vida , Masculino , Resistencia Física , Análisis de Regresión , Entrenamiento de Fuerza
11.
Scand J Rheumatol ; 39(3): 233-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20429674

RESUMEN

OBJECTIVES: Physical activity (PA) has the potential to improve outcomes in both arthritis and diabetes, but these conditions are rarely examined together. Our objective was to explore whether persons with arthritis alone or those with both arthritis and diabetes could improve amounts of PA with a home-based counselling intervention. METHODS: As part of the Veterans LIFE (Learning to Improve Fitness and Function in Elders) Study, veterans aged 70-92 were randomized to usual care or a 12-month PA counselling programme. Arthritis and diabetes were assessed by self-report. Mixed models were used to compare trajectories for minutes of endurance and strength training PA for persons with no arthritis (n = 85), arthritis (n = 178), and arthritis plus diabetes (n = 84). RESULTS: Recipients of PA counselling increased minutes of PA per week independent of disease status (treatment arm by time interaction p < 0.05 for both; endurance training time p = 0.0006 and strength training time p < 0.0001). Although PA was lower at each wave among persons with arthritis, and even more so among persons with arthritis plus diabetes, the presence of these conditions did not significantly influence response to the intervention (arthritis/diabetes group x time interactions p > 0.05 for both outcomes) as each group experienced a nearly twofold or greater increase in PA. CONCLUSIONS: A home-based PA intervention was effective in increasing minutes of weekly moderate intensity endurance and strength training PA in older veterans, even among those with arthritis or arthritis plus diabetes. This programme may serve as a useful model to improve outcomes in older persons with these pervasive diseases.


Asunto(s)
Artritis/psicología , Consejo , Diabetes Mellitus/psicología , Ejercicio Físico/psicología , Autocuidado/psicología , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Estudios Transversales , Ejercicio Físico/fisiología , Promoción de la Salud/métodos , Humanos , Actividad Motora , Cooperación del Paciente/psicología , Educación del Paciente como Asunto/métodos , Aptitud Física/fisiología , Aptitud Física/psicología , Autocuidado/métodos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Veteranos
12.
Int J Lab Hematol ; 31(6): 603-14, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18691345

RESUMEN

The latest version of our Laboratory Information System haematology laboratory expert system that handles the output of Abbott Cell-Dyn Sapphires, CD4000s and a CD3200 full blood count analyser in three high-volume haematology laboratories is described. The three hospital laboratories use Cerner Millennium Version 2007.02 software and the expert system uses Cerner Millennium Discern Expert rules and some small Cerner Command Language in-house programs. The entire expert system is totally integrated with the area-wide database and has been built and maintained by haematology staff members, as has the haematology database. Using patient demographic data, analyser numeric results, analyser error and morphology flags and previous results for the patient, this expert system decides whether to validate the main full blood count indices and white cell differential, or if the analyser results warrant further operator intervention/investigation before verifying, whether a blood film is required for microscopic review and if abnormal results require phoning to the staff treating the patient. The principles of this expert system can be generalized to different haematology analysers and haematology laboratories that have different workflows and different software.


Asunto(s)
Recuento de Células Sanguíneas/instrumentación , Sistemas de Información en Laboratorio Clínico , Sistemas Especialistas , Pruebas Hematológicas/instrumentación , Adulto , Australia , Niño , Preescolar , Sistemas de Información en Laboratorio Clínico/instrumentación , Humanos , Lactante , Recién Nacido , Masculino , Programas Informáticos
13.
Artículo en Inglés | MEDLINE | ID: mdl-19163999

RESUMEN

We present for the first time the integration of nanohole arrays for surface plasmon resonance (SPR) sensing together with SU-8 polymer microfluidic channels containing special packaging structures for chip-to-chip and world-to-chip interconnect. Primary steps towards an optical biospecies detection device are presented including observing the effect of period on transmission peak location, examining new materials for the enclosed microchannels, and demonstrating nanohole array SPR transmission data through water contained in the microchannels. Additionally, the enclosed microchannels are integrated with interconnect structures that facilitate interfacing with macro-scale test equipment and microfluidic components and systems such as lab-on-a-chip. Results demonstrate the potential of the polymer microchannels with integrated nanohole arrays and interconnect as a packaged optical SPR detection device.


Asunto(s)
Técnicas Biosensibles/instrumentación , Compuestos Epoxi/química , Técnicas Analíticas Microfluídicas/instrumentación , Nanotecnología/instrumentación , Dispositivos Ópticos , Polímeros/química , Resonancia por Plasmón de Superficie/instrumentación , Transductores , Técnicas Biosensibles/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Nanotecnología/métodos , Porosidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resonancia por Plasmón de Superficie/métodos
14.
Rheumatology (Oxford) ; 46(3): 523-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17003168

RESUMEN

OBJECTIVES: Osteonecrosis of the femoral head results from interruption of the vascular supply and eventual death of the cellular portion of bone. Effective methods of monitoring response to treatment are needed. Our aim was to evaluate synovial fluid metabolites, glucose and lactate, as biomarkers in a canine model of osteonecrosis. METHODS: Osteonecrosis was cryosurgically induced in the right femoral head while the left hip served as control (n = 31). Animals either underwent no further intervention (n = 10), vascular endothelial growth factor (VEGF) injections (n = 4), placement of a vascularized bone graft (n = 6), a combination of VEGF microinjection and vascularized graft placement (n = 5), or treatment with daily oral alendronate (n = 6). After 12 weeks, synovial fluid from each hip joint was obtained for glucose and lactate concentrations. RESULTS: Joints with surgically induced osteonecrosis demonstrated decreased synovial fluid concentrations of glucose (P < 0.05) and elevated concentrations of lactate (P < 0.05) relative to contralateral control hips. When animals were treated with VEGF, the vascularized graft placement, or vascularized graft and VEGF, there were no differences in the synovial fluid concentrations of these metabolites between cryoablated and control hips. In contrast, alendronate did not normalize the concentration of these synovial fluid metabolites in the cryoablated hips. CONCLUSIONS: Osteonecrosis of the femoral head is associated with alterations in synovial fluid glucose and lactate, reflecting anaerobic metabolism. These metabolites may serve as useful tools for monitoring response to revascularization therapies.


Asunto(s)
Necrosis de la Cabeza Femoral/metabolismo , Líquido Sinovial/metabolismo , Animales , Biomarcadores/metabolismo , Trasplante Óseo , Terapia Combinada , Modelos Animales de Enfermedad , Perros , Necrosis de la Cabeza Femoral/patología , Necrosis de la Cabeza Femoral/terapia , Glucosa/metabolismo , Ácido Láctico/metabolismo , Factor A de Crecimiento Endotelial Vascular/uso terapéutico
15.
J Matern Fetal Med ; 10(5): 332-4, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11730497

RESUMEN

OBJECTIVE: To determine whether the method of placing a 25-microg misoprostol chip into the posterior fornix to achieve cervical ripening affects the drug's efficacy. METHODS: A pill inserter was used to place a misoprostol chip into the posterior fornix for the purpose of cervical ripening prior to induction of labor. Data from a control group were obtained by retrospective chart review. RESULTS: The control and study groups contained 49 patients each. Compared to placing the misoprostol chip with a lubricated finger, the use of the pill inserter resulted in statistically significantly more patients receiving only one dose. This occurred either because a Bishop score of 8 or greater was achieved or because repeat dosing was disallowed secondary to the onset of uterine contractions. Although the total number of patients subsequently requiring oxytocin was significantly increased, there was no difference in the use of oxytocin for either induction or augmentation of labor. The lengths of the latent and active phases of labor did not differ between the two groups. CONCLUSION: The number of doses of a 25-microg misoprostol chip for cervical ripening that result in uterine contractions, with or without a change in the Bishop score, is affected by the method used to place it in the vagina.


Asunto(s)
Maduración Cervical , Sistemas de Liberación de Medicamentos/instrumentación , Misoprostol/administración & dosificación , Oxitócicos/administración & dosificación , Administración Intravaginal , Adulto , Femenino , Guantes Quirúrgicos , Humanos , Registros Médicos , Embarazo , Estudios Retrospectivos
16.
J Neurosci ; 21(21): 8348-53, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11606622

RESUMEN

Superoxide is produced as a result of normal energy metabolism within the mitochondria and is scavenged by the mitochondrial form of superoxide dismutase (sod2). Mice with inactivated SOD2 (sod2 nullizygous mice) die prematurely, exhibiting several metabolic and mitochondrial defects and severe tissue pathologies, including a lethal spongiform neurodegenerative disorder (Li et al., 1995; Melov et al., 1998, 1999). We show that treatment of sod2 nullizygous mice with synthetic superoxide dismutase (SOD)-catalase mimetics extends their lifespan by threefold, rescues the spongiform encephalopathy, and attenuates mitochondrial defects. This class of antioxidant compounds has been shown previously to extend lifespan in the nematode Caenorhabditis elegans (Melov et al., 2000). These new findings in mice suggest novel therapeutic approaches to neurodegenerative diseases associated with oxidative stress such as Friedreich ataxia, spongiform encephalopathies, and Alzheimer's and Parkinson's diseases, in which chronic oxidative damage to the brain has been implicated.


Asunto(s)
Antioxidantes/administración & dosificación , Depuradores de Radicales Libres/administración & dosificación , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/enzimología , Superóxido Dismutasa/deficiencia , Animales , Antioxidantes/química , Catalasa , Catálisis , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Etilenodiaminas/administración & dosificación , Etilenodiaminas/química , Depuradores de Radicales Libres/química , Inyecciones Intraperitoneales , Lípidos/química , Metaloporfirinas/administración & dosificación , Ratones , Ratones Noqueados , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/química , Estrés Oxidativo/efectos de los fármacos , Fenotipo , Salicilatos/administración & dosificación , Salicilatos/química , Superóxido Dismutasa/genética , Tasa de Supervivencia
17.
Cereb Cortex ; 11(9): 849-67, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11532890

RESUMEN

The functional organization of area 3a, a cortical field proposed to be involved in somato-motor-vestibular integration, has never been described for any primate. In the present investigation, the topographic organization and connections of area 3a were examined in marmosets using electrophysiological recording and anatomical tracing techniques. Multi-unit neuronal activity was recorded at a number of closely spaced sites; receptive fields (RFs) for neurons were determined, and the optimal stimulus was identified. In all cases, neurons in area 3a responded to the stimulation of deep receptors on the contralateral body. The representation of the body in area 3a was from the toes and foot, to the hindlimb, trunk, forelimb, hand and face in a mediolateral progression. In all cases electrophysiological results were related to myeloarchitecture, and the map in area 3a was found to be coextensive with a strip of lightly to moderately myelinated cortex just rostral to the darkly myelinated 3b. To examine the cortical connections of area 3a, injections of anatomical tracers were made into electrophysiologically identified body part representations. Area 3a has dense intrinsic connections and receives substantial inputs from the primary motor cortex (M1), the supplementary motor area (SMA), areas 1 and 2, the second somatosensory area (S2), and areas in posterior parietal cortex (PP). The connections of area 3a indicate that integration of cortical representations of body parts occurs both within area 3a and between area 3a and other somatosensory and motor areas. In addition, there are differential patterns of interconnections between behaviorally relevant body part representations of area 3a, such as the forelimb, compared to other body part representations (hindlimb/ trunk), especially with 'higher order' cortical fields. This suggests that 3a may be an important component in a network that generates a common frame of reference for hand and eye coordinated reaching tasks.


Asunto(s)
Mapeo Encefálico/métodos , Callithrix/fisiología , Corteza Cerebral/fisiología , Células Receptoras Sensoriales/fisiología , Animales , Cara/fisiología , Miembro Anterior/fisiología , Vías Nerviosas/fisiología
18.
Exp Neurol ; 171(1): 84-97, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11520123

RESUMEN

Neuronal apoptosis induced by staurosporine (STS) involves multiple cellular and molecular events, such as the production of reactive oxygen species (ROS). In this study, we tested the efficacy of two synthetic superoxide dismutase/catalase mimetics (EUK-134 and EUK-189) on neuronal apoptosis, oxidative stress, and mitochondrial dysfunction produced by STS in primary cortical neuronal cultures. Exposure of cultures to STS for 24 h increased lactate dehydrogenase (LDH) release, the number of apoptotic cells, and decreased trypan blue exclusion. Pretreatment with 20 microM EUK-134 or 0.5 microM EUK-189 significantly attenuated STS-induced neurotoxicity, as did pretreatment with the caspase-1 inhibitor, Ac-YVAD-CHO, but not the caspase-3 inhibitor, Ac-DEVD-CHO. Posttreatment (1-3 h following STS exposure) with 20 microM EUK-134 or 0.5 microM EUK-189 significantly reduced STS-induced LDH release, in a time-dependent manner. Exposure of cultures to STS for 1 h produced an elevation of ROS, as determined by increased levels of 2,7-dichlorofluorescein (DCF). This rapid elevation of ROS was followed by an increase in lipid peroxidation, and both the increase in DCF fluorescence and in lipid peroxidation were significantly blocked by pretreatment with EUK-134. STS treatment for 3-6 h increased cytochrome c release from mitochondria into the cytosol, an effect also blocked by pretreatment with EUK-134. These results indicate that intracellular oxidative stress and mitochondrial dysfunction are critically involved in STS-induced neurotoxicity. However, there are additional cellular responses to STS, which are insensitive to treatment with radical scavengers that also contribute to its neurotoxicity.


Asunto(s)
Apoptosis/efectos de los fármacos , Catalasa , Neuronas/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Estaurosporina/farmacología , Superóxido Dismutasa/farmacología , Animales , Células Cultivadas , Corteza Cerebral , Grupo Citocromo c/metabolismo , Relación Dosis-Respuesta a Droga , Etiquetado Corte-Fin in Situ , L-Lactato Deshidrogenasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neuronas/citología , Neuronas/metabolismo , Compuestos Organometálicos/farmacología , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Salicilatos/farmacología , Estaurosporina/antagonistas & inhibidores
19.
Biochem Soc Symp ; (67): 141-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11447830

RESUMEN

It is well established that inflammation and oxidative stress are key components of the pathology of Alzheimer's disease (AD), but how early in the pathological cascade these processes are involved or which specific molecular components are key, has not been fully elucidated. This paper describes the pharmacological approach to understand the molecular components of inflammation and oxidative stress on the activation of microglial cells and neuronal cell viability. We have shown that activation of microglia with the 42-amino-acid form of the beta-amyloid peptide (A beta 42) activates the production of cyclooxygenase-2, the inducible form of nitric oxide synthase and tumour necrosis factor-alpha and there appears to be little interactive feedback between these three mediators. Moreover, we explore the effects of a series of salen-manganese complexes, EUK-8, -134 and -189, which are known to possess both superoxide and catalase activity. These compounds are able to protect cells from insults produced by hydrogen peroxide or peroxynitrite. Moreover, EUK-134 was also able to limit the output of prostaglandin E2 from activated microglial cells. The mechanisms underlying these effects are discussed. Together, these data support a pivotal role for oxidative stress and inflammation as key mediators of the pathological cascade in AD and provide some ideas about possible therapeutic targets.


Asunto(s)
Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/metabolismo , Estrés Oxidativo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/farmacología , Animales , Células Cultivadas , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Dinoprostona/biosíntesis , Humanos , Inflamación/etiología , Mediadores de Inflamación/metabolismo , Isoenzimas/metabolismo , Lipopolisacáridos/farmacología , Proteínas de la Membrana , Microglía/efectos de los fármacos , Microglía/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Prostaglandina-Endoperóxido Sintasas/metabolismo , Ratas , Transducción de Señal , Factor de Necrosis Tumoral alfa/biosíntesis
20.
J Comp Neurol ; 435(3): 291-310, 2001 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-11406813

RESUMEN

The present investigation is part of a broader effort to examine cortical areas that contribute to manual dexterity, reaching, and grasping. In this study we examine the thalamic connections of electrophysiologically defined regions in area 3a and architectonically defined primary motor cortex (M1). Our studies demonstrate that area 3a receives input from nuclei associated with the somatosensory system: the superior, inferior, and lateral divisions of the ventral posterior complex (VPs, VPi, and VPl, respectively). Surprisingly, area 3a receives the majority of its input from thalamic nuclei associated with the motor system, posterior division of the ventral lateral nucleus of the thalamus (VL), the mediodorsal nucleus (MD), and intralaminar nuclei including the central lateral nucleus (CL) and the centre median nucleus (CM). In addition, sparse but consistent projections to area 3a are from the anterior pulvinar (Pla). Projections from the thalamus to the cortex immediately rostral to area 3a, in the architectonically defined M1, are predominantly from VL, VA, CL, and MD. There is a conspicuous absence of inputs from the nuclei associated with processing somatic inputs (VP complex). Our results indicate that area 3a is much like a motor area, in part because of its substantial connections with motor nuclei of the thalamus and motor areas of the neocortex (Huffman et al. [2000] Soc. Neurosci. Abstr. 25:1116). The indirect input from the cerebellum and basal ganglia via the ventral lateral nucleus of the thalamus supports its role in proprioception. Furthermore, the presence of input from somatosensory thalamic nuclei suggests that it plays an important role in somatosensory and motor integration.


Asunto(s)
Callithrix/anatomía & histología , Corteza Motora/citología , Movimiento/fisiología , Vías Nerviosas/citología , Propiocepción/fisiología , Corteza Somatosensorial/citología , Tálamo/citología , Potenciales de Acción/fisiología , Animales , Transporte Axonal/efectos de los fármacos , Transporte Axonal/fisiología , Mapeo Encefálico , Callithrix/fisiología , Electrofisiología , Colorantes Fluorescentes/farmacocinética , Mecanorreceptores/citología , Mecanorreceptores/fisiología , Corteza Motora/fisiología , Vías Nerviosas/fisiología , Neuronas/citología , Neuronas/fisiología , Estimulación Física , Corteza Somatosensorial/fisiología , Tálamo/fisiología , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre Conjugada/farmacocinética
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