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1.
Eur J Appl Physiol ; 121(8): 2187-2192, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33876259

RESUMEN

INTRODUCTION: Non-steroidal anti-inflammatory drugs (NSAIDs) taken before exercise have been shown to impair bone formation. NSAIDs also suppress inflammatory cytokines, such as interleukin-6 (IL-6), that can have pro-resorptive effects. It is unclear how taking NSAIDs timed around exercise influences inflammatory and bone biomarkers following an acute exercise bout in older adults. PURPOSE: To determine if timing of ibuprofen use relative to a single exercise bout has acute effects on serum IL-6, bone-specific alkaline phosphatase (BAP, marker of bone formation), and c-telopeptide of type I collagen (CTX, marker of bone resorption). METHODS: As part of a 36-week exercise intervention, participants aged 60 to 75 years were randomized to 3 groups: placebo before and after exercise (PP), ibuprofen before and placebo after exercise (IP), or placebo before and ibuprofen after exercise (PI). Acute responses were studied in a subset of participants (12 PP, 17 IP, 13 PI). Blood was sampled before and immediately, 30 min, and 60 min after exercise for IL-6, BAP, and CTX. RESULTS: The exercise-induced increase in IL-6 was blunted in response to IP when compared to PI 60-min after exercise (p < 0.001). There were no significant differences in the change in BAP or CTX between groups at any time points CONCLUSION: Ibuprofen taken before exercise dampened the inflammatory response to exercise but had no effects on bone biomarkers in older adults. It may be necessary to monitor changes for a longer time interval after an acute exercise bout to determine whether bone turnover is altered by ibuprofen or other NSAIDs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00462722; Posted 04/19/2007.


Asunto(s)
Fosfatasa Alcalina/sangre , Antiinflamatorios no Esteroideos/administración & dosificación , Colágeno Tipo I/sangre , Ejercicio Físico , Ibuprofeno/administración & dosificación , Interleucina-6/sangre , Péptidos/sangre , Anciano , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Clin Endocrinol (Oxf) ; 90(2): 293-300, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30421439

RESUMEN

OBJECTIVE: Studies of dehydroepiandrosterone (DHEA) therapy in older adults suggest sex-specific effects on bone mineral density (BMD) and body composition, but the ability of a single study to reach this conclusion was limited. We evaluated the effects of DHEA on sex hormones, BMD, fat mass and fat-free mass in older women and men enrolled in four similar clinical trials. DESIGN: Pooled analyses of data from four double-blinded, randomized controlled trials. PARTICIPANTS: Women (n = 295) and men (n = 290) aged 55 years or older who took DHEA or placebo tablet daily for 12 months. MEASUREMENTS: Twelve-month changes in BMD, fat mass, fat-free mass and serum DHEA sulphate (DHEAS), (17)estradiol, testosterone and insulin-like growth factor-1 (IGF-1). RESULTS: Women on DHEA had increases (mean ± SD; all P < 0.001 vs placebo) in DHEAS (231 ± 164 µg/dL), testosterone (18.6 ± 20.9 µg/dL), (17)estradiol (8.7 ± 11.0 pg/mL) and IGF-1 (25.1 ± 52.3 ng/mL), and men had increases in DHEAS (269.0 ± 177 µg/dL; P < 0.01), (17)estradiol (4.8 ± 12.2 pg/m; P < 0.01) and IGF-1 (6.3 ± 41.4 ng/mL; P < 0.05). Women on DHEA had increases in lumbar spine (1.0% ± 3.4%) and trochanter (0.5% ± 3.8%) BMD and maintained total hip BMD (0.0% ± 2.8%); men had no BMD benefit and a decrease in fat mass (-0.4 ± 2.6 kg; all P < 0.01 vs placebo). CONCLUSIONS: Dehydroepiandrosterone therapy may be an effective approach for preserving bone and muscle mass in women. Key questions are (a) the extent to which longer duration DHEA can attenuate the loss of bone and muscle in women, and (b) whether DHEA has a more favourable benefit-to-risk profile for women than oestrogen therapy.


Asunto(s)
Composición Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Deshidroepiandrosterona/farmacología , Factores Sexuales , Anciano , Deshidroepiandrosterona/metabolismo , Femenino , Fémur/efectos de los fármacos , Terapia de Reemplazo de Hormonas , Humanos , Vértebras Lumbares/efectos de los fármacos , Masculino , Persona de Mediana Edad , Huesos Pélvicos/efectos de los fármacos , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Am J Physiol Endocrinol Metab ; 315(2): E316-E325, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29631362

RESUMEN

Sex hormones appear to play a role in the regulation of hypothalamic-pituitary-adrenal (HPA) axis activity. The objective was to isolate the effects of estradiol (E2) on central activation of the HPA axis. We hypothesized that the HPA axis response to corticotropin-releasing hormone (CRH) under dexamethasone (Dex) suppression would be exaggerated in response to chronic ovarian hormone suppression and that physiologic E2 add-back would mitigate this response. Thirty premenopausal women underwent 20 wk of gonadotropin-releasing hormone agonist therapy (GnRHAG) and transdermal E2 (0.075 mg per day, GnRHAG + E2, n = 15) or placebo (PL) patch (GnRHAG + PL, n = 15). Women in the GnRHAG + PL and GnRHAG + E2 groups were of similar age (38 (SD 5) yr vs. 36 (SD 7) yr) and body mass index (27 (SD 6) kg/m2 vs. 27 (SD 6) kg/m2). Serum E2 changed differently between the groups ( P = 0.01); it decreased in response to GnRHAG + PL (77.9 ± 17.4 to 23.2 ± 2.6 pg/ml; P = 0.008) and did not change in response to GnRHAG + E2 (70.6 ± 12.4 to 105 ± 30.4 pg/ml; P = 0.36). The incremental area under the curve (AUCINC) responses to CRH were different between the groups for total cortisol ( P = 0.03) and cortisone ( P = 0.04) but not serum adrenocorticotropic hormone (ACTH) ( P = 0.28). When examining within-group changes, GnRHAG + PL did not alter the HPA axis response to Dex/CRH, but GnRHAG + E2 decreased the AUCINC for ACTH (AUCINC, 1,623 ± 257 to 1,211 ± 236 pg/ml·min, P = 0.004), cortisone (1,795 ± 367 to 1,090 ± 281 ng/ml·min, P = 0.009), and total cortisol (7,008 ± 1,387 to 3,893 ± 1,090 ng/ml·min, P = 0.02). Suppression of ovarian hormones by GnRHAG therapy for 20 wk did not exaggerate the HPA axis response to CRH, but physiologic E2 add-back reduced HPA axis activity compared with preintervention levels.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Hormona Liberadora de Gonadotropina/agonistas , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Premenopausia/fisiología , Adiposidad/efectos de los fármacos , Hormona Adrenocorticotrópica/sangre , Adulto , Composición Corporal/efectos de los fármacos , Cortisona/análisis , Cortisona/metabolismo , Dexametasona/farmacología , Método Doble Ciego , Estradiol/farmacología , Femenino , Humanos , Hidrocortisona/análisis , Hidrocortisona/metabolismo , Persona de Mediana Edad
4.
Arch Phys Med Rehabil ; 97(7): 1154-62, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27063363

RESUMEN

OBJECTIVE: To investigate whether sex affects the trajectory of functional recovery after total knee arthroplasty (TKA). DESIGN: Retrospective analysis from a historical database containing data from 3 prospective clinical trials and a pilot study. SETTING: Clinical laboratory setting. PARTICIPANTS: Recruitment across studies was restricted to patients who underwent an elective unilateral TKA for the treatment of osteoarthritis and were between 50 and 85 years of age (N=301). INTERVENTIONS: Across all 4 studies, patients received a TKA and physical therapy intervention. Measures of physical function and strength were assessed before TKA and 1, 3, and 6 months after TKA. MAIN OUTCOME MEASURES: Using a repeated-measures maximum likelihood model, statistical inference was made to estimate the changes in outcomes from before surgery to 1, 3, and 6 months after TKA that were stratified by sex. Muscle strength was assessed during maximal isometric quadriceps and hamstrings contractions. Muscle activation was assessed in the quadriceps muscle. Physical function outcomes included timed Up and Go (TUG) test, stair climbing test, and 6-minute walk test (6MWT). RESULTS: Women demonstrated less decline in quadriceps strength than did men at 1, 3, and 6 months after TKA (P<.04), whereas women demonstrated less decline in hamstrings strength 1 month after TKA (P<.0001). Women demonstrated a greater decline than did men on the TUG test (P=.001), stair climbing test (P=.004), and 6MWT (P=.001) 1 month after TKA. Sex differences in physical function did not persist at 3 and 6 months after TKA. CONCLUSIONS: Sex affected early recovery of muscle and physical function in the first month after TKA. Women demonstrated better preservation of quadriceps strength but a greater decline on measures of physical function than did men.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/rehabilitación , Músculo Esquelético/fisiopatología , Modalidades de Fisioterapia , Anciano , Anciano de 80 o más Años , Ensayos Clínicos como Asunto , Evaluación de la Discapacidad , Femenino , Humanos , Contracción Isométrica/fisiología , Funciones de Verosimilitud , Masculino , Persona de Mediana Edad , Limitación de la Movilidad , Músculo Cuádriceps/fisiopatología , Recuperación de la Función , Estudios Retrospectivos , Factores Sexuales , Factores de Tiempo
5.
J Antimicrob Chemother ; 70(8): 2322-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25971261

RESUMEN

OBJECTIVES: Ribavirin concentrations may impact hepatitis C virus (HCV) treatment outcome. We modelled ribavirin serum and intracellular ribavirin monophosphate (RBV-MP) and ribavirin triphosphate (RBV-TP) pharmacokinetics in red blood cells (RBC) using samples collected during the NIAID SPARE trial to explore associations with treatment outcome and the development of anaemia. PATIENTS AND METHODS: Individuals infected with HCV genotype 1 (GT1) received 400 mg of sofosbuvir and either low-dose or weight-based ribavirin as part of the NIAID SPARE trial. Concentrations were modelled using NONMEM and associated with treatment outcomes using unpaired t-tests or Pearson's rho correlations. RESULTS: Average day 14 RBV-MP concentrations were higher in subjects with haemoglobin nadir <10 g/dL relative to patients with haemoglobin nadir ≥10 g/dL (6.54 versus 4.48 pmol/10(6) cells; P = 0.02). Additionally, day 14 RBV-MP average concentrations trended towards being higher in subjects that achieved sustained virological response (SVR) as compared with patients who relapsed (4.97 versus 4.09 pmol/10(6) cells; P = 0.07). Receiver operating characteristic curves suggested day 14 RBV-MP concentration thresholds of 4.4 pmol/10(6) cells for SVR (P = 0.06) and 6.1 pmol/10(6) cells for haemoglobin nadir <10 versus ≥10 g/dL (P = 0.02), with sensitivity and specificity ≥60%. Dosing simulations showed that 800 mg of ribavirin once daily produced day 14 RBV-MP concentrations within the 4.4-6.1 pmol/10(6) cells range. CONCLUSIONS: RBV-MP concentrations in RBC at day 14 were related to anaemia and SVR. A therapeutic range was identified for RBV-MP in persons with HCV GT1 disease receiving 24 weeks of sofosbuvir plus ribavirin, suggesting a potential pharmacological basis for individualized ribavirin dosing in IFN-free regimens.


Asunto(s)
Antivirales/administración & dosificación , Antivirales/farmacocinética , Eritrocitos/química , Ribavirina/administración & dosificación , Ribavirina/farmacocinética , Suero/química , Sofosbuvir/administración & dosificación , Adulto , Anciano , Anemia/inducido químicamente , Antivirales/efectos adversos , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Ribavirina/efectos adversos , Resultado del Tratamiento , Carga Viral
6.
J Behav Med ; 37(2): 332-42, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23329423

RESUMEN

Cardiometabolic risk factors, including hypertension, dyslipidemia, central obesity, insulin resistance and diabetes are linked to cognitive impairment. The Hispanic population appears to be differentially affected by both cardiometabolic risk factors and cognitive impairment. We sought to determine whether ethnic differences in cognitive impairment in long-resident southwestern US elders was explained by the presence of cardiometabolic risk factors, and to explore patterns of cognitive decline over time. We performed a secondary analysis of data collected on 378 Hispanic and 409 non-Hispanic white adult participants in a longitudinal study of community-dwelling elderly in southern Colorado. Measures of cardiometabolic risk included waist circumference, blood pressure, diagnosis of diabetes, and random blood glucose. Cognitive measures included the Mini-Mental State Exam (MMSE) and the behavioral dyscontrol scale (a measure of executive cognitive function), at baseline and after an average of 22 months. Subjects were also administered the Center for Epidemiologic Studies Depression Scale, and the Coronary Artery Risk Development in Young Adults 1-Year Activity Recall. At baseline, Hispanic elders had a greater number of cardiometabolic risk factors and lower MMSE and behavioral dyscontrol scale scores than non-Hispanic whites. Hispanic ethnicity was associated with a greater likelihood of decline in general cognitive function, but not executive cognitive function, after adjusting for age and education. This differential decline was not explained by either individual or total number of baseline cardiometabolic risk factors, depression, or physical activity. A borderline increased risk of decline in general cognitive function was seen in sedentary individuals (P = 0.05).


Asunto(s)
Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/psicología , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/psicología , Susceptibilidad a Enfermedades/psicología , Hispánicos o Latinos/psicología , Población Blanca/psicología , Anciano , Anciano de 80 o más Años , Envejecimiento , Glucemia/análisis , Presión Sanguínea/fisiología , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/fisiopatología , Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/complicaciones , Colorado/epidemiología , Depresión/sangre , Depresión/complicaciones , Depresión/fisiopatología , Depresión/psicología , Diabetes Mellitus/fisiopatología , Susceptibilidad a Enfermedades/sangre , Susceptibilidad a Enfermedades/complicaciones , Susceptibilidad a Enfermedades/fisiopatología , Función Ejecutiva , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora , Factores de Riesgo , Circunferencia de la Cintura/fisiología
7.
Clin Orthop Relat Res ; 472(2): 654-64, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23817756

RESUMEN

BACKGROUND: Patients undergoing total hip arthroplasty (THA) often are satisfied with the decrease in pain and improvement in function they achieve after surgery. Even so, strength and functional performance deficits persist after recovery, but these remain poorly characterized; knowledge about any ongoing strength or functional deficits may allow therapists to design rehabilitation programs to optimize recovery after THA. QUESTIONS/PURPOSES: The purposes of this study were to (1) evaluate postoperative muscle strength, function, and quality of life during the first year after THA; and (2) compare strength and function in patients 1 year after THA with a cohort of healthy peers. METHODS: Twenty-six patients undergoing THA were assessed 1, 3, 6, and 12 months postoperatively, and 19 adults with no hip pathology were tested as a control group. Isometric muscle strength (hip flexors, extensors, abductors, knee extensors, and flexors), functional performance (stair climbing, five times sit-to-stand, timed-up-and-go, 6-minute walk, and single-limb stance tests), and self-reported function (Hip Disability and Osteoarthritis Score, SF-36, and UCLA activity score) were compared. RESULTS: One month after THA, patients had 15% less hip flexor and extensor torque, 26% less abductor torque, 14% less knee extensor and flexor torque, and worse performance on the stair climbing, timed-up-and-go, single-limb stance, and 6-minute walk. Compared with healthy adults, patients 12 months after THA had 17% less knee extensor and 23% less knee flexor torque; however, the functional testing (including stair climbing, five times sit-to-stand, and the 6-minute walk) showed no significant differences with the patient numbers available between individuals undergoing THA and healthy control subjects. SF-36 Physical Component Scores, although significantly improved from preoperative levels, were significantly worse than healthy adults 1 year after THA (p < 0.01). CONCLUSIONS: Patients experience early postoperative strength losses and decreased functional capacity after THA, yet strength deficits may persist after recovery. This may suggest that rehabilitation may be most effective in the first month after surgery.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Articulación de la Cadera/cirugía , Fuerza Muscular , Músculo Esquelético/cirugía , Actividades Cotidianas , Anciano , Artroplastia de Reemplazo de Cadera/rehabilitación , Fenómenos Biomecánicos , Estudios de Casos y Controles , Colorado , Evaluación de la Discapacidad , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Contracción Isométrica , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Examen Físico , Estudios Prospectivos , Calidad de Vida , Recuperación de la Función , Encuestas y Cuestionarios , Factores de Tiempo , Torque , Resultado del Tratamiento
8.
Clin J Sport Med ; 24(4): 331-6, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24326929

RESUMEN

OBJECTIVE: To observe changes in hip, spine, and tibia bone characteristics in female cyclists over the course of 1 year of training. DESIGN: Prospective observational study. SETTING: Laboratory. PARTICIPANTS: Female cyclists (n = 14) aged 26-41 years with at least 1 year of competition history and intent to compete in 10 or more races in the coming year. ASSESSMENT OF RISK FACTORS: Women who train and compete in road cycling as their primary sport. MAIN OUTCOME MEASURES: Total body fat-free and fat mass and lumbar spine and proximal femur areal bone mineral density (aBMD) and bone mineral content (BMC) assessments by dual-energy x-ray absorptiometry. Volumetric BMD and BMC of the tibia were measured by peripheral quantitative computed tomography at sites corresponding to 4%, 38%, 66%, and 96% of tibia length. Time points were baseline and after 12 months of training and competition. RESULTS: Weight and body composition did not change significantly over 12 months. Total hip aBMD and BMC decreased by -1.4% ± 1.9% and -2.1% ± 2.3% (P < 0.02) and subtrochanter aBMD and BMC decreased by -2.1% ± 2.0% and -3.3% ± 3.7% (P < 0.01). There was a significant decrease in lumbar spine BMC (-1.1% ± 1.9%; P = 0.03). There were no significant bone changes in the tibia (P > 0.11). CONCLUSIONS: Bone loss in female cyclists was site specific and similar in magnitude to losses previously reported in male cyclists. Research is needed to understand the mechanisms for bone loss in cyclists.


Asunto(s)
Ciclismo/fisiología , Resorción Ósea/etiología , Huesos/fisiología , Adolescente , Adulto , Atletas , Densidad Ósea , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
9.
Eur J Appl Physiol ; 113(5): 1127-36, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23108581

RESUMEN

N-acetyl-4-aminophenol (ACET) may impair musculoskeletal adaptations to progressive resistance exercise training (PRT) by inhibiting exercise-induced muscle protein synthesis and bone formation. To test the hypothesis that ACET would diminish training-induced increases in fat-free mass (FFM) and osteogenesis, untrained men (n = 26) aged ≥50 years participated in 16 weeks of high-intensity PRT and bone-loading exercises and were randomly assigned to take ACET (1,000 mg/day) or placebo (PLAC) 2 h before each exercise session. Total body FFM was measured by DXA at baseline and week 16. Serum bone-specific alkaline phosphatase (BAP) and C-terminal crosslinks of type-I collagen (CTX) were measured at baseline and week 16. Vastus lateralis muscle biopsies were performed at baseline and weeks 3 and 16 for prostanoid, anabolic, and catabolic gene expression by RT-PCR. In exercise-compliant men (ACET, n = 10; PLAC, n = 7), the increase in FFM was not different between groups (p = 0.91). The changes in serum BAP and CTX were not different between groups (p > 0.7). There were no significant changes in any of the target genes at week 3. After 16 weeks of PRT, the mRNA expressions of the anabolic marker p70S6K (p = 0.003) and catabolic marker muscle-atrophy F-box (MAFbx) (p = 0.03) were significantly reduced as compared to baseline in ACET. The mRNA expression of the prostanoids were unchanged (all p ≥ 0.40) in both groups. The administration of ACET (1,000 mg) prior to each exercise session did not impair PRT-induced increases in FFM or significantly alter bone formation markers in middle aged and older men.


Asunto(s)
Acetaminofén/farmacología , Adaptación Fisiológica , Huesos/efectos de los fármacos , Ejercicio Físico , Músculo Esquelético/efectos de los fármacos , Entrenamiento de Fuerza , Fosfatasa Alcalina/sangre , Huesos/metabolismo , Huesos/fisiología , Estudios de Casos y Controles , Colágeno Tipo I/sangre , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Osteogénesis/efectos de los fármacos , Péptidos/sangre , Transcripción Genética/efectos de los fármacos
10.
Breast Cancer Res ; 14(1): R1, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22225711

RESUMEN

INTRODUCTION: Healthy body weight is an important factor for prevention of breast cancer recurrence. Yet, weight loss and weight gain are not currently included in clinical-practice guidelines for posttreatment of breast cancer. The work reported addresses one of the questions that must be considered in recommending weight loss to patients: does it matter what diet plan is used, a question of particular importance because breast cancer treatment can increase risk for cardiovascular disease. METHODS: Women who completed treatment for breast cancer were enrolled in a nonrandomized, controlled study investigating effects of weight loss achieved by using two dietary patterns at the extremes of macronutrient composition, although both diet arms were equivalent in protein: high fat, low carbohydrate versus low fat, high carbohydrate. A nonintervention group served as the control arm; women were assigned to intervention arms based on dietary preferences. During the 6-month weight-loss program, which was menu and recipe defined, participants had monthly clinical visits at which anthropometric data were collected and fasting blood was obtained for safety monitoring for plasma lipid profiles and fasting glucose. Results from 142 participants are reported. RESULTS: Adverse effects on fasting blood lipids or glucose were not observed in either dietary arm. A decrease in fasting glucose was observed with progressive weight loss and was greater in participants who lost more weight, but the effect was not statistically significant, even though it was observed across both diet groups (P = 0.21). Beneficial effects of weight loss on cholesterol (4.7%; P = 0.001), triglycerides (21.8%; P = 0.01), and low-density lipoprotein (LDL) cholesterol (5.8%; P = 0.06) were observed in both groups. For cholesterol (P = 0.07) and LDL cholesterol (P = 0.13), greater reduction trends were seen on the low-fat diet pattern; whereas, for triglycerides (P = 0.01) and high-density lipoprotein (HDL) cholesterol (P = 0.08), a decrease or increase, respectively, was greater on the low-carbohydrate diet pattern. CONCLUSIONS: Because an individual's dietary preferences can affect dietary adherence and weight-loss success, the lack of evidence of a negative effect of dietary pattern on biomarkers associated with cardiovascular risk is an important consideration in the development of breast cancer practice guidelines for physicians who recommend that their patients lose weight. Whether dietary pattern affects biomarkers that predict long-term survival is a primary question in this ongoing clinical trial.


Asunto(s)
Glucemia , Neoplasias de la Mama/prevención & control , Lípidos/sangre , Recurrencia Local de Neoplasia/prevención & control , Obesidad/dietoterapia , Sobrevivientes , Índice de Masa Corporal , Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Análisis de Regresión , Resultado del Tratamiento , Pérdida de Peso
11.
Biomedicines ; 11(1)2022 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-36672557

RESUMEN

Damage to cellular macromolecules such as DNA and lipid, induced via reactive oxygen species, and indicators of cell proliferation potential such as insulin-like growth factor (IGF) metabolic status are intermediate biomarkers of breast cancer risk. Based on reports that selenium status can affect these markers, a randomized, placebo-controlled, double-blind experiment was conducted to investigate the potential of selenium supplementation to modulate breast cancer risk. Using a placebo tablet or a tablet containing 200 µg selenium provided as high-selenium yeast daily for one year, concentrations of the biomarkers in blood or urine were assessed at baseline and after 6 and 12 months of intervention. The selenium intervention used in this study is presumed to mediate its effect via the induction of glutathione peroxidase activity and the consequential impact of the active form of this protein on oxidative damage. We found no evidence to support this hypothesis or to indicate that systemic IGF metabolic status was affected. Critical knowledge gaps must be addressed for the resurgence of interest in selenium and cancer to garner clinical relevance. Those knowledge gaps include the identification of a specific, high-affinity selenium metabolite and the cellular target(s) to which it binds, and the demonstration that the cellular determinant that the selenium metabolite binds plays a critical role in the initiation, promotion, or progression of a specific type of cancer.

12.
Clin Endocrinol (Oxf) ; 75(4): 456-63, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21521341

RESUMEN

OBJECTIVE: To determine the effects of dehydroepiandrosterone (DHEA) therapy on changes in central adiposity, insulin action and blood lipids. Many of the actions of DHEA in humans are thought to be mediated through its conversion to sex hormones, which are modulators of adiposity, muscularity and insulin sensitivity. The effects of DHEA replacement on regional tissue composition, glucose metabolism and blood lipid profile in older adults have been inconsistent. DESIGN: A randomized, double-blinded, placebo-controlled trial. The intervention was oral DHEA 50 mg/day or placebo for 12 months. PARTICIPANTS: Fifty-eighty women and 61 men, aged 60-88 years, with low serum DHEA sulphate (DHEAS) levels at study entry. MEASUREMENTS: Computed tomography measures of abdominal fat areas, thigh muscle and fat areas, DXA-derived trunk fat mass, serum glucose and insulin responses to an oral glucose challenge, and fasted serum total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides were assessed before and after the intervention. RESULTS: There were no significant (P > 0·05) differences between the DHEA and placebo groups in the changes in regional tissue composition or glucose metabolism. HDL-cholesterol (P = 0·01) and fasted triglycerides (P = 0·02) decreased in women and men taking DHEA. CONCLUSION: Restoring serum DHEAS levels in older adults to young adult levels for 1 year does not appear to reduce central adiposity or improve insulin action. The benefit of DHEA on decreasing serum triglycerides must be weighed against the HDL-lowering effect.


Asunto(s)
Adiposidad/fisiología , Deshidroepiandrosterona/uso terapéutico , Glucosa/metabolismo , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Placebos , Triglicéridos/sangre
13.
BMC Cancer ; 11: 287, 2011 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-21733177

RESUMEN

BACKGROUND: Weight loss in overweight or obese breast cancer patients is associated with an improved prognosis for long term survival. However, it is not clear whether the macronutrient composition of the chosen weight loss dietary plan imparts further prognostic benefit. A study protocol is presented for a dietary intervention to investigate the effects of weight loss dietary patterns that vary markedly in fat and carbohydrate contents on biomarkers of exposure to metabolic processes that may promote tumorigenesis and that are predictive of long term survival. The study will also determine how much weight must be lost for biomarkers to change in a favorable direction. METHODS/DESIGN: Approximately 370 overweight or obese postmenopausal breast cancer survivors (body mass index: 25.0 to 34.9 kg/m²) will be accrued and assigned to one of two weight loss intervention programs or a non-intervention control group. The dietary intervention is implemented in a free living population to test the two extremes of popular weight loss dietary patterns: a high carbohydrate, low fat diet versus a low carbohydrate, high fat diet. The effects of these dietary patterns on biomarkers for glucose homeostasis, chronic inflammation, cellular oxidation, and steroid sex hormone metabolism will be measured. Participants will attend 3 screening and dietary education visits, and 7 monthly one-on-one dietary counseling and clinical data measurement visits in addition to 5 group visits in the intervention arms. Participants in the control arm will attend two clinical data measurement visits at baseline and 6 months. The primary outcome is high sensitivity C-reactive protein. Secondary outcomes include interleukin-6, tumor necrosis factor-α, insulin-like growth factor-1 (IGF), IGF binding protein-3, 8-isoprostane-F2-alpha, estrone, estradiol, progesterone, sex hormone binding globulin, adiponectin, and leptin. DISCUSSION: While clinical data indicate that excess weight for height is associated with poor prognosis for long term survival, little attention is paid to weight control in the clinical management of breast cancer. This study will provide information that can be used to answer important patient questions about the effects of dietary pattern and magnitude of weight loss on long term survival following breast cancer treatment. CLINICAL TRIAL REGISTRATION: CA125243.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/dietoterapia , Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Sobrevivientes , Adiponectina/sangre , Tejido Adiposo/metabolismo , Algoritmos , Análisis de Varianza , Neoplasias de la Mama/metabolismo , Proteína C-Reactiva/metabolismo , Estrógenos/sangre , Femenino , Glucosa/metabolismo , Homeostasis/efectos de los fármacos , Humanos , Interleucina-6/metabolismo , Leptina/sangre , Persona de Mediana Edad , Obesidad/sangre , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Posmenopausia/sangre , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Programas de Reducción de Peso/métodos , Programas de Reducción de Peso/estadística & datos numéricos
14.
J Health Care Finance ; 38(2): 38-53, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22372031

RESUMEN

OBJECTIVE: To examine the impact of the coverage gap on pharmacy use, expenditures, and out-of-pocket costs for Medicare managed care beneficiaries before and after reaching the gap. STUDY DESIGN: A longitudinal comparison of behaviors for beneficiaries with non-gap coverage before and after reaching the gap. METHODS: Prescription drug use and expenditures were assessed for Medicare beneficiaries who reached the gap, including subsets with one of four chronic disorders (congestive heart failure (CHF), diabetes, dyslipidemia, or hypertension). Differences in pre- and post-prescription use were calculated using generalized estimating equations. Time until the end and start of the gap was estimated using a Cox proportional hazards model. Expenditure data were estimated using bootstrap methods. RESULTS: Roughly a quarter (27.1 percent) of patients reached the gap in 2006, of whom 3.6 percent passed through the gap. The most prevalent disease state was hypertension (58.5 percent). Beneficiaries took an average of 8.1 months to reach the gap. Patients <65 years (HR = 1.42, 95% CI = 1.29 - 1.56) and those with diabetes (HR = 1.19, 95% CI = 1.12 - 1.27) were more likely to reach the gap sooner as compared to older beneficiaries (aged 65 to 74) and those without diabetes. These individuals were more likely to pass through the gap as well. Beneficiaries faced a 60.7 percent increase in out-of-pocket expenditures in the gap phase. Brand-name medication use decreased by 9.3 percent, while generic medication use increased by 7.4 percent. For chronic conditions, however, over 90 percent of individuals continued brand-name medication use in the gap. CONCLUSIONS: Our findings suggest that, in general, beneficiaries take lower-cost generics while in the gap. However, taking brand-name medications is the predominant behavior for beneficiaries with chronic diseases. Health care reform provisions that close the gap over the next ten years may facilitate continuity of medication use while in the gap.


Asunto(s)
Cobertura del Seguro/economía , Programas Controlados de Atención en Salud , Medicare Part D , Anciano , Anciano de 80 o más Años , Femenino , Financiación Personal/tendencias , Gastos en Salud/tendencias , Humanos , Revisión de Utilización de Seguros , Estudios Longitudinales , Masculino , Servicios Farmacéuticos/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Estados Unidos
15.
Carcinogenesis ; 31(7): 1279-83, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20299525

RESUMEN

Emerging evidence indicates that intrinsic differences and induced changes in aerobic capacity are probably to play a critical role in the development of chronic diseases like cancer. This study was initiated: (i) to determine how citrate synthase activity, which is routinely used as a marker of aerobic capacity and mitochondrial density in skeletal muscle, was affected by voluntary running on either a motorized activity wheel or a non-motorized free wheel and (ii) to investigate the association between aerobic capacity and the carcinogenic response induced in the mammary gland by intraperitoneal injection of 1-methyl-1-nitrosurea. Overall, wheel running reduced cancer incidence (96 versus 72%, P = 0.0006) and the number of cancers per animal (2.84 versus 1.78, P < 0.0001) and induced citrate synthase activity (276 versus 353 U/mg, P < 0.0001, sedentary control versus wheel running,respectively). Both motorized and free wheel running increased citrate synthase activity (373 +/- 24, 329 +/- 11 and 276 +/- 9 U/mg protein, P < 0.0001) and reduced the average number of cancers per rat (2.84, 1.96 and 1.63, P < 0.01), sedentary control, free wheel and motorized wheel, respectively. However, regression analyses failed to provide evidence of a significant association between citrate synthase activity and either cancer incidence or cancer multiplicity. Citrate synthase activity is a single measure in a complex pathway that determines aerobic capacity. The multifaceted nature of intrinsic and inducible aerobic capacity limits the usefulness of citrate synthase activity alone in elucidating the relationship between aerobic capacity and the carcinogenic response.


Asunto(s)
Neoplasias Mamarias Experimentales/inducido químicamente , Músculo Esquelético/metabolismo , Consumo de Oxígeno , Condicionamiento Físico Animal , Carrera , Aerobiosis , Animales , Citrato (si)-Sintasa/metabolismo , Femenino , Modelos Logísticos , Metilnitrosourea , Ratas , Ratas Sprague-Dawley , Proteína p53 Supresora de Tumor/fisiología
16.
Am J Physiol Endocrinol Metab ; 299(4): E576-83, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20628023

RESUMEN

Cellular effects of FFA might differ from those of lipoprotein triglyceride (TG)-derived fatty acids (TGFA). The aim of the current study was to examine the relationship between lipoprotein lipase (LPL) expression, TGFA, or FFA availability and glucose metabolism in the absence of insulin in C2C12 myoblasts. Control myoblasts or myoblasts stably transfected with human lipoprotein lipase (C2/LPL; 15-fold greater LPL activity) were incubated for 12 h in fetal bovine serum-free medium in the absence or presence of Intralipid-20. Intracellular retention of labeled medium glucose was assessed in a subset of experiments. In the presence of Intralipid, medium glucose disappearance was increased in C2/LPL cells but not in control cells. In both cell types, glucose label retention in cellular TG was increased in the presence of Intralipid; incubation with albumin-bound oleate produced similar results. In the presence of Intralipid, the LPL hydrolytic inhibitor tetrahydrolipstatin blocked excess glucose retention in cellular TG but did not significantly decrease glucose disappearance in C2/LPL cells. Changes in glucose transport or hexokinase II did not explain the altered glucose disappearance in C2/LPL cells. Our results suggest that LPL overexpression in these cells leads to chronic metabolic adaptations that alter glucose uptake and retention.


Asunto(s)
Emulsiones Grasas Intravenosas/farmacología , Glucosa/metabolismo , Lipoproteína Lipasa/metabolismo , Músculo Esquelético/metabolismo , Animales , Western Blotting , Línea Celular , Ácidos Grasos no Esterificados/metabolismo , Humanos , Lactonas/farmacología , Lipoproteína Lipasa/antagonistas & inhibidores , Lipoproteína Lipasa/genética , Lipoproteínas/metabolismo , Ratones , Músculo Esquelético/citología , Músculo Esquelético/enzimología , Mioblastos/enzimología , Mioblastos/metabolismo , Orlistat , Transfección , Triglicéridos/metabolismo
17.
J Manag Care Spec Pharm ; 26(5): 575-585, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32347176

RESUMEN

OBJECTIVE: To evaluate the impact of 3-tier (copayment) pharmacy benefit structures on medication utilization behavior. METHODS: A pretest-posttest quasi-experimental design was employed. Chronic disease sufferers (N=8,132) from a health plan were classified into the following groups: (a) 2-tier copayment moving to a 3-tier structure, ("converting" group), (b) 2-tier staying in a 2-tier structure and, (c) 3-tier staying in a 3-tier structure. The latter 2 were "comparison" groups. Two 7-month time periods were determined: the "preperiod" (June through December 2000) and the "postperiod" (January through July 2001) for a change in pharmacy benefit structure. Pharmacy claims data were used for data collection. Statistical analyses included bivariate tests to evaluate predifferences and postdifferences across study groups. Maximum likelihood estimates from a repeated measures model were used to examine changes in formulary compliance and generic use rates. Discontinuation of nonformulary medications was evaluated using logistic regression. RESULTS: Controlling for demographics, number of comorbidities, disease state, and pharmacy benefit structure, the formulary compliance rate increased by 5.6% for the converting group. No significant increases were seen for the comparison groups. Generic use rates increased by 6 to 8 absolute percentage points for all groups (3.3% to 4.9 % adjusted rates). Converting group members were 1.76 times more likely to discontinue their nonformulary medication than those in the 2-tier comparison group and 1.49 times more likely than those in the 3-tier comparison group. CONCLUSIONS: These findings suggest that shifting individuals from a 2-tier to a 3-tier drug benefit copayment structure resulted in changes in medication utilization. Decision makers need to balance these changes with the potential dissatisfaction that members may express in paying higher copayments. DISCLOSURES: Funding for this research was provided by Merck and Company through the Academic Medicine and Managed Care Forum and was obtained by authors Kavita V. Nair, Robert J. Valuck, Pamela Wolfe, Julie M. Ganther, and Marianne M. McCollum. Nair served as principal author of the study. Study concept and design was contributed by Nair, Valuck, Wolfe, Ganther, McCollum, and author Sonya J. Lewis. Analysis and interpretation of data and drafting of the manuscript were primarily the work of Nair and Wolfe, and all authors contributed to the critical revision of the manuscript. Statistical expertise was contributed by Wolfe. Administrative, technical, and/or material support was provided by Mark Enders.


Asunto(s)
Conducta de Elección , Enfermedad Crónica , Seguro de Costos Compartidos/economía , Medicamentos Genéricos/economía , Seguro de Servicios Farmacéuticos/economía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Encuestas y Cuestionarios , Estados Unidos
18.
Mov Disord ; 24(10): 1481-7, 2009 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-19441128

RESUMEN

Gait dysfunction is an early problem identified by patients with Parkinson's disease (PD). Alterations in gait may result in an increase in the energy cost of walking (i.e., walking economy). The purpose of this study was to determine whether walking economy is atypical in patients with PD when compared with healthy controls. A secondary purpose was to evaluate the associations of age, sex, and level of disease severity with walking economy in patients with PD. The rate of oxygen consumption (VO(2)) and other responses to treadmill walking were compared in 90 patients (64.4 +/- 10.3 years) and 44 controls (64.6 +/- 7.3 years) at several walking speeds. Pearson correlation coefficients (r) were calculated to determine relationships of age, sex, and disease state with walking economy in PD patients. Walking economy was significantly worse in PD patients than in controls at all speeds above 1.0 mph. Across all speeds, VO(2) was 6 to 10% higher in PD patients. Heart rate, minute ventilation, respiratory exchange ratio, and rating of perceived exertion were correspondingly elevated. No significant relationship of age, sex, or UPDRS score with VO(2) was found for patients with PD. The findings suggest that the physiologic stress of daily physical activities is increased in patients with early to mid-stage PD, and this may contribute to the elevated level of fatigue that is characteristic of PD.


Asunto(s)
Consumo de Oxígeno/fisiología , Enfermedad de Parkinson/fisiopatología , Caminata/fisiología , Anciano , Prueba de Esfuerzo/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Estadística como Asunto
19.
Int J Rehabil Res ; 42(3): 211-216, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31219844

RESUMEN

Total joint replacement is indicated to alleviate pain and disability associated with hip and knee osteoarthritis. Arthroplasty outcomes are typically reported together, or anecdotal comparisons are made between total knee arthroplasty (TKA) and total hip arthroplasty (THA) recovery. Limited data quantifies differences in recovery trajectories, especially with respect to performance-based outcomes. Seventy-nine people undergoing total knee or THA were followed over 6 months. Functional performance was measured using the stair climb test, timed-up-and-go test, and 6-min walk test. Surgical limb isometric strength was also measured. All outcomes significantly declined 1 month after surgery. Participants in the TKA group showed a greater decline in climbing stairs (P < 0.001), timed-up-and-go (P = 0.01), and 6-min walk distance (P < 0.01). Further, the TKA group lost more strength (P < 0.001) and were weaker than those after THA (P < 0.001). Differences in postoperative outcomes between groups at 3 and 6 months were also observed. The TKA group experiences a greater decline in measured outcomes than the THA group, and muscle strength and functional recovery occurred differently in each group. These findings should be considered in rehabilitation priorities after arthroplasty surgery.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Prueba de Esfuerzo , Fuerza Muscular , Rendimiento Físico Funcional , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/cirugía , Osteoartritis de la Rodilla/cirugía
20.
Med Sci Sports Exerc ; 51(8): 1599-1605, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31083027

RESUMEN

Endurance exercise can cause a decrease in serum ionized calcium (iCa) and increases in parathyroid hormone (PTH) and c-terminal telopeptide of type I collagen (CTX), which may be due to Ca loss in sweat. PURPOSE: This study aimed to determine whether exercise in a warm environment exaggerates the decrease in iCa and increases in PTH and CTX compared with a cool environment in older adults. METHODS: Twelve women and men 61-78 yr old performed two identical 60-min treadmill bouts at ~75% of maximal heart rate under warm and cool conditions. Serum iCa, PTH, and CTX were measured every 15 min starting 15 min before and continuing for 60 min after exercise. Sweat Ca loss was estimated from sweat volume and sweat Ca concentration. RESULTS: Sweat volume was low and variable; there were no differences in sweat volume or Ca concentration between conditions. iCa decreased after 15 min of exercise, and the change was similar in both conditions. Increases in PTH (warm: 16.4, 95% confidence interval [CI] = 6.2, 26.5 pg·mL; cool: 17.3, 95% CI = 8.1, 26.4 pg·mL) and CTX (warm: 0.08, 95% CI = 0.05, 0.11 ng·mL; cool: 0.08, 95% CI = 0.01, 0.16 ng·mL) from before to immediately after exercise were statistically significant and similar between conditions. Adjusting for plasma volume shifts did not change the results. CONCLUSION: The increases in PTH and CTX, despite the low sweat volume, suggest that dermal Ca loss is not a major factor in the decrease in iCa and increases in PTH and CTX observed during exercise in older adults.


Asunto(s)
Huesos/metabolismo , Calcio/sangre , Colágeno Tipo I/sangre , Calor , Hormona Paratiroidea/sangre , Péptidos/sangre , Caminata/fisiología , Anciano , Biomarcadores/sangre , Densidad Ósea , Frío , Colágeno Tipo I/orina , Femenino , Homeostasis , Humanos , Masculino , Persona de Mediana Edad , Péptidos/orina , Piel/metabolismo , Sudor/metabolismo , Sudoración/fisiología
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