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1.
J Endocrinol Invest ; 42(11): 1337-1343, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31127591

RESUMEN

PURPOSE: Aromatase inhibitors (AIs) represent the first-line adjuvant therapy for hormone receptor-positive breast cancer (BC) women. AIs have been associated with an increased rate of fractures. The aim of our study was to investigate trabecular bone score (TBS) and bone quantitative ultrasound (QUS) measurements as bone quality surrogates in AIs users. METHODS: Sixty postmenopausal BC women starting AIs and forty-two controls (mean age 61.64 ± 8.33 years) were considered. Bone mineral density (BMD) at lumbar spine and femoral neck and TBS were measured by DXA; QUS-derived Amplitude-Dependent Speed of Sound (AD-SoS), Bone Transmission Time (BTT), and Ultrasound Bone Profile Index (UBPI) were assessed at phalangeal site; morphometric vertebral fractures (Vfx) by X-ray, serum bone-specific alkaline phosphatase (BSAP), and C-telopeptide of type 1 collagen (CTX) were also evaluated. RESULTS: After 18 months, changes of TBS vs baseline were significantly different between AIs group and controls [Δ TBS - 2.2% vs - 0.4%, respectively, p = 0.001]. AD-SoS, BTT and UBPI values decreased only in AIs' group (- 3.7%, - 6.45%, -8.5%, vs baseline, respectively, pall < 0.001). 3 Vfx occurred in AIs users and were associated with the greater TBS and AD-SoS modifications. In the AIs' group, ΔTBS was associated with ΔAD-SoS (r = 0.58, p < 0.001) and ΔUBPI (r = 0.415, p = 0.001), but not with ΔBMD. Moreover, ΔTBS was independently predicted by ΔAD-SoS, after correcting for BMD, CTX and BSAP level changes (ß = 0.37, SE = 2.44, p < 0.001). CONCLUSIONS: TBS and phalangeal QUS provide useful information related to bone quality in AI-treated BC survivors and could be considered for fracture risk evaluation.


Asunto(s)
Inhibidores de la Aromatasa/efectos adversos , Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Hueso Esponjoso/efectos de los fármacos , Supervivientes de Cáncer/estadística & datos numéricos , Osteoporosis Posmenopáusica/diagnóstico , Ultrasonografía/métodos , Hueso Esponjoso/diagnóstico por imagen , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/inducido químicamente , Osteoporosis Posmenopáusica/diagnóstico por imagen , Pronóstico , Medición de Riesgo
2.
Bone ; 125: 103-111, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31077852

RESUMEN

PURPOSE: Children with Hutchinson-Gilford progeria syndrome (HGPS), a rare premature aging disease, exhibit extraskeletal calcifications detected by radiographic analysis and on physical examination. The aim of this study was to describe the natural history and pathophysiology of these abnormal calcifications in HGPS, and to determine whether medications and/or supplements tested in clinical trials alter their development. METHODS: Children from two successive clinical trials administering 1) lonafarnib (n = 26) and 2) lonafarnib + pravastatin + zoledronic acid (n = 37) were studied at baseline (pre-therapy), one year on therapy, and at end-of-therapy (3.3-4.3 years after the baseline visit). Calcium supplementation (oral calcium carbonate) was administered during the first year of the second trial and was subsequently discontinued. Information on calcifications was obtained from physical examinations, radiographs, and serum and urinary biochemical measures. The mineral content of two skin-derived calcifications was determined by x-ray diffraction. RESULTS: Extraskeletal calcifications were detected radiographically in 12/39 (31%) patients at baseline. The odds of exhibiting calcifications increased with age (p = 0.045). The odds were unaffected by receipt of lonafarnib, pravastatin, and zoledronate therapies. However, administration of calcium carbonate supplementation, in conjunction with all three therapeutic agents, significantly increased the odds of developing calcifications (p = 0.009), with the odds plateauing after the supplement's discontinuation. Composition analysis of calcinosis cutis showed hydroxyapatite similar to bone. Although serum calcium, phosphorus, and parathyroid hormone (PTH) were within normal limits at baseline and on-therapy, PTH increased significantly after lonafarnib initiation (p < 0.001). Both the urinary calcium/creatinine ratio and tubular reabsorption of phosphate (TRP) were elevated at baseline in 22/39 (56%) and 31/37 (84%) evaluable patients, respectively, with no significant changes while on-therapy. The mean calcium × phosphorus product (Ca × Pi) was within normal limits, but plasma magnesium decreased over both clinical trials. Fibroblast growth factor 23 (FGF23) was lower compared to age-matched controls (p = 0.03). CONCLUSIONS: Extraskeletal calcifications increased with age in children with HGPS and were composed of hydroxyapatite. The urinary calcium/creatinine ratio and TRP were elevated for age while FGF23 was decreased. Magnesium decreased and PTH increased after lonafarnib therapy which may alter the ability to mobilize calcium. These findings demonstrate that children with HGPS with normal renal function and an unremarkable Ca × Pi develop extraskeletal calcifications by an unidentified mechanism that may involve decreased plasma magnesium and FGF23. Calcium carbonate accelerated their development and is, therefore, not recommended for routine supplementation in these children.


Asunto(s)
Calcinosis/patología , Progeria/patología , Calcinosis/sangre , Calcinosis/diagnóstico por imagen , Calcinosis/tratamiento farmacológico , Calcio/sangre , Niño , Preescolar , Creatinina/sangre , Femenino , Factor-23 de Crecimiento de Fibroblastos , Humanos , Técnicas In Vitro , Lamina Tipo A/metabolismo , Masculino , Hormona Paratiroidea/sangre , Hormona Paratiroidea/metabolismo , Piperidinas/uso terapéutico , Pravastatina/uso terapéutico , Progeria/sangre , Progeria/diagnóstico por imagen , Progeria/tratamiento farmacológico , Piridinas/uso terapéutico , Ácido Zoledrónico/uso terapéutico
3.
J Matern Fetal Neonatal Med ; 25(9): 1660-3, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22280352

RESUMEN

BACKGROUND: As the vitamin K content of human milk is low and the newborn infant's stores of vitamin K are small, vitamin K deficiency with hemorrhage in the newborn is a worldwide problem. Proteins Induced by Vitamin K Absence (PIVKA-II) are the inactive under-γ-carboxylated forms of vitamin K-dependent clotting factors and they could be useful in predicting subclinical vitamin K deficiency (VKD). OBJECTIVES: To demonstrate that PIVKA-II are earlier markers of subclinical VKD than Prothrombin time (PT) in exclusively breast-fed newborns. METHODS: A prospective, controlled, randomized study, including 53 term newborns receiving vitamin K prophylaxis (0.5 mg i.m.) at birth, was performed. At 30 days newborns were divided into three groups (G) receiving respectively: 25 µg/die of vitamin K (G I), 12 µg/die (G II) or placebo (G III). PIVKA-II and PT were measured on 30th and 90th days of life. RESULTS: G III and GII showed a significant increase in PIVKA-II from 30 to 90 days of life respectively from 2.6 to 4.7 (p = 0.001) and from 2.3 to 3.5 (p < 0.001). No significant changes were found in GI. PT showed no significant changes among groups. CONCLUSIONS: PT is a less sensitive marker than PIVKA II. Oral supplementation with 25 µg/die avoids an increase of PIVKA-II. Despite increased PIVKA-II do not mean an impending occurrence of bleeding, they highlight a subclinical VKD and its relative risk.


Asunto(s)
Biomarcadores/sangre , Precursores de Proteínas/sangre , Nacimiento a Término/sangre , Deficiencia de Vitamina K/diagnóstico , Enfermedades Asintomáticas , Biomarcadores/análisis , Suplementos Dietéticos , Diagnóstico Precoz , Sangre Fetal/química , Humanos , Lactante , Recién Nacido , Precursores de Proteínas/análisis , Precursores de Proteínas/fisiología , Protrombina/análisis , Protrombina/fisiología , Tiempo de Protrombina , Factores de Tiempo , Vitamina K/administración & dosificación , Deficiencia de Vitamina K/sangre , Deficiencia de Vitamina K/tratamiento farmacológico
4.
Atherosclerosis ; 205(2): 549-53, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19195657

RESUMEN

BACKGROUND: Observational studies generally showed beneficial associations between supplemental vitamin E intake and cardiovascular disease (CVD) risk whereas intervention trials reported adverse effects of vitamin E supplements. We hypothesize that these discordant findings result from differing underlying health status of study participants in observational and intervention studies. OBJECTIVE: Determine if the relation between supplemental vitamin E intake and CVD and all-cause mortality (ACM) depends on pre-existing CVD. DESIGN: Proportional hazards regression to relate supplemental vitamin E intake to the 10-year incidence of CVD and ACM in 4270 Framingham Study participants stratified by baseline CVD status. RESULTS: Eleven percent of participants used vitamin E supplements at baseline. In participants with pre-existing CVD, there were 28 (44%) and 20 (32%) incident cases of CVD and ACM in the vitamin E supplement users versus 249 (47%) and 202 (38%) in the non-users, respectively (CVD HR, 0.90; 95% CL, 0.60-1.32; ACM HR, 0.74; 95% CL, 0.46-1.17). In participants without pre-existing CVD, there were 51 (13%) and 47 (12%) cases of CVD and ACM in the vitamin E supplement group versus 428 (13%) and 342 (10%) in the non-vitamin E supplement group, respectively (CVD HR, 1.00; 95% CL, 0.75-1.34; ACM HR 1.20; 95% CL, 0.89-1.64). CONCLUSION: CVD status has no apparent influence on the association of supplemental vitamin E intake and risk for CVD and ACM in this large, community-based study. Further research is needed to clarify the basis for the discrepant results between intervention and observational studies of supplemental vitamin E intake.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Suplementos Dietéticos , Vitamina E/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Riesgo
5.
Antimicrob Agents Chemother ; 45(5): 1535-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11302823

RESUMEN

The present study evaluated in vitro and in vivo a new chlorhexidine (C)-silver sulfadiazine (S) vascular catheter (the CS2 catheter) characterized by a higher C content and by the extended release of the surface-bound antimicrobials. The CS2 catheter was compared with a first-generation, commercially available CS catheter (the CS1 catheter). The CS2 catheter produced slightly smaller zones of inhibition (mean difference, 0.9 mm [P < 0.001]) at 24 h against Staphylococcus aureus and five other microorganisms by several different methodologies. However, in a rabbit model, both CS catheters were similarly efficacious in preventing a catheter infection when the rabbits were inoculated with 10(4) to 10(7) CFU of S. aureus at the time of catheter insertion. The CS2 catheter retained its antimicrobial activity significantly longer in vitro and in vivo (half-lives exceeded 34 and 7 days, respectively) and was also significantly more efficacious in preventing a catheter infection when 10(6) CFU of S. aureus was inoculated 2 days after catheter implantation (P < 0.001). These results suggest that prolonged anti-infective activity on the external catheter surface provides improved efficacy in the prevention of infection.


Asunto(s)
Antiinfecciosos Locales/farmacología , Catéteres de Permanencia , Clorhexidina/uso terapéutico , Infecciones Relacionadas con Prótesis/prevención & control , Sulfadiazina de Plata/uso terapéutico , Infecciones Estafilocócicas/prevención & control , Animales , Clorhexidina/farmacología , Modelos Animales de Enfermedad , Combinación de Medicamentos , Pruebas de Sensibilidad Microbiana , Conejos , Sulfadiazina de Plata/farmacología , Staphylococcus aureus/efectos de los fármacos
6.
Cancer Epidemiol Biomarkers Prev ; 8(8): 693-8, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10744129

RESUMEN

This study evaluated the effects of vitamin E (alpha-tocopherol) on oxidative DNA damage in a randomized double-blind Phase II chemoprevention trial. Oxidative DNA damage was measured by the level of auto-antibody (Ab) against 5-hydroxymethyl-2'-deoxyuridine (HMdU) in plasma. After the baseline screening, eligible subjects (n = 31; plasma samples from 28 subjects were available for this study) were randomized to receive 15, 60, or 200 mg of alpha-tocopherol per day for 28 days. Biomarkers were measured twice at baseline--on day 1 (visit 1) and day 3 (visit 2)--and twice after intervention--on day 17 (visit 3) and day 31 (visit 4). At baseline, there was a highly significant inverse correlation between anti-HMdU Ab titer and plasma vitamin E level (r = -0.53; P = 0.004; n = 28). Smoking did not affect baseline anti-HMdU Ab titer; however, anti-HMdU Ab titer levels at baseline were significantly lower in subjects with above-median (0.75 ounce/day) alcohol consumption (P = 0.008). No significant change in anti-HMdU Ab level occurred at either visit 3 or visit 4 for subjects on the lowest dose, 15 mg alpha-tocopherol per day. Subjects receiving 60 mg of alpha-tocopherol per day had a significant decrease in anti-HMdU Ab level at visits 3 and 4 compared with baseline (P = 0.049 and P = 0.02, respectively). However, subjects receiving the highest dose, 200 mg/day, had less consistent results: a significant decrease in anti-HMdU Ab level was seen at visit 4 (P = 0.04) but not at visit 3. Our results demonstrate an inverse relationship between alpha-tocopherol and anti-HMdU Abs in plasma; oxidative DNA damage can be modulated by short-term dietary supplementation of alpha-tocopherol in some subjects.


Asunto(s)
Autoanticuerpos/análisis , Daño del ADN , Reparación del ADN , Desoxiuridina/análogos & derivados , Vitamina E/farmacología , Adulto , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/prevención & control , Especies Reactivas de Oxígeno , Vitamina E/uso terapéutico
7.
Circulation ; 97(18): 1837-47, 1998 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-9603539

RESUMEN

BACKGROUND: The objective of this study was to examine the association of Joint National Committee (JNC-V) blood pressure and National Cholesterol Education Program (NCEP) cholesterol categories with coronary heart disease (CHD) risk, to incorporate them into coronary prediction algorithms, and to compare the discrimination properties of this approach with other noncategorical prediction functions. METHODS AND RESULTS: This work was designed as a prospective, single-center study in the setting of a community-based cohort. The patients were 2489 men and 2856 women 30 to 74 years old at baseline with 12 years of follow-up. During the 12 years of follow-up, a total of 383 men and 227 women developed CHD, which was significantly associated with categories of blood pressure, total cholesterol, LDL cholesterol, and HDL cholesterol (all P<.001). Sex-specific prediction equations were formulated to predict CHD risk according to age, diabetes, smoking, JNC-V blood pressure categories, and NCEP total cholesterol and LDL cholesterol categories. The accuracy of this categorical approach was found to be comparable to CHD prediction when the continuous variables themselves were used. After adjustment for other factors, approximately 28% of CHD events in men and 29% in women were attributable to blood pressure levels that exceeded high normal (> or =130/85). The corresponding multivariable-adjusted attributable risk percent associated with elevated total cholesterol (> or =200 mg/dL) was 27% in men and 34% in women. CONCLUSIONS: Recommended guidelines of blood pressure, total cholesterol, and LDL cholesterol effectively predict CHD risk in a middle-aged white population sample. A simple coronary disease prediction algorithm was developed using categorical variables, which allows physicians to predict multivariate CHD risk in patients without overt CHD.


Asunto(s)
Presión Sanguínea , Colesterol/sangre , Enfermedad Coronaria/epidemiología , Adulto , Anciano , Algoritmos , Índice de Masa Corporal , LDL-Colesterol/clasificación , Estudios de Cohortes , Comorbilidad , Diabetes Mellitus/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud , Modelos de Riesgos Proporcionales , Factores de Riesgo , Fumar/epidemiología
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