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1.
Biofactors ; 32(1-4): 221-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19096119

RESUMEN

Our work has identified an aging-related ECTO-NOX activity (arNOX), a hydroquinone oxidase which is cell surface located and generates superoxide. This activity increases with increasing age beginning >30 y. Because of its cell surface location and ability to generate superoxide, the arNOX proteins may serve to propagate an aging cascade both to adjacent cells and to oxidize circulating lipoproteins as significant factors determining atherogenic risk. The generation of superoxide by arNOX proteins is inhibited by Coenzyme Q10 as one basis for an anti-aging benefit of CoQ10 supplementation in human subjects. In a preliminary pilot study, 25 female subjects between 45 and 55 y of age were recruited at Stanford University from the Palo Alto, CA area. Informed consent was obtained. Ten of the subjects received Coenzyme Q10 supplementation of 180 (3 x 60 mg) per day for 28 days. Serum, saliva and perspiration levels of arNOX were determined at 7, 14 and 28 days of CoQ10 supplementation and compared to the initial baseline value. Activity correlated with subject age up to a maximum between age 50 and 55 years of age for saliva and perspiration as well and then declined. With all three sources, the arNOX activity extrapolated to zero at about age 30. Response to Coenzyme Q10 also increased with age being least between ages 45 and 50 and greatest between ages 60 and 65. With all three biofluids, arNOX activity was reduced between 25 and 30% by a 3 x 60 mg daily dose Coenzyme Q10 supplementation. Inhibition was the result of Coenzyme Q10 presence.


Asunto(s)
NADH NADPH Oxidorreductasas/metabolismo , Ubiquinona/análogos & derivados , Adulto , Anciano , Envejecimiento , Femenino , Humanos , Masculino , Persona de Mediana Edad , NADH NADPH Oxidorreductasas/efectos de los fármacos , Proyectos Piloto , Saliva/efectos de los fármacos , Saliva/enzimología , Sudor/efectos de los fármacos , Sudor/enzimología , Ubiquinona/administración & dosificación
2.
Int J Radiat Oncol Biol Phys ; 69(5): 1369-76, 2007 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-17855005

RESUMEN

PURPOSE: To assess the safety of long-term cevimeline treatment of radiation-induced xerostomia in patients with head-and-neck cancer; and to assess the efficacy of cevimeline in these patients. METHODS AND MATERIALS: A total of 255 adults with head-and-neck cancer who had received more than 40 Gy of radiation 4 months or more before entry and had clinically significant salivary gland dysfunction received cevimeline hydrochloride 45 mg t.i.d. orally for 52 weeks. Adverse events (AEs), their severity, and their relationship to the study medication were assessed by each investigator. The efficacy assessment was based on subjects' global evaluation of oral dryness on a scale of 0 (none) to 3 (severe). RESULTS: Overall, 175 subjects (68.6%) experienced expected treatment-related AEs, most mild to moderate. The most frequent was increased sweating (47.5%), followed by dyspepsia (9.4%), nausea (8.2%), and diarrhea (6.3%). Fifteen subjects (5.9%) experienced Grade 3 treatment-related AEs, of which the most frequent was increased sweating. Eighteen subjects (7.1%) reported at least one serious AE, and 45 subjects (17.6%) discontinued study medication because of an AE. The global efficacy evaluation at the last study visit showed that cevimeline improved dry mouth in most subjects (59.2%). Significant improvement was seen at each study visit in the mean change from baseline of the numeric global evaluation score (p < 0.0001). CONCLUSIONS: Cevimeline 45 mg t.i.d. was generally well tolerated over a period of 52 weeks in subjects with xerostomia secondary to radiotherapy for cancer in the head-and-neck region.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Agonistas Muscarínicos/efectos adversos , Quinuclidinas/efectos adversos , Tiofenos/efectos adversos , Xerostomía/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Diarrea/inducido químicamente , Dispepsia/inducido químicamente , Femenino , Humanos , Masculino , Persona de Mediana Edad , Agonistas Muscarínicos/administración & dosificación , Náusea/inducido químicamente , Quinuclidinas/administración & dosificación , Dosificación Radioterapéutica , Sudor/efectos de los fármacos , Tiofenos/administración & dosificación
3.
Radiother Oncol ; 36(1): 56-64, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8525026

RESUMEN

Following irradiation of the left-hind feet of mice, we measured the ability of the eccrine glands to secrete sweat following stimulation by pilocarpine. Silicone elastomer impression moulds of the foot pads gave repeatable, detailed localization of sweat ducts by retaining the impression of each emerging sweat droplet. Loss of gland function occurred rapidly following irradiation (within 2 weeks) and the rate of loss was dose-dependent, being over three times greater following a dose of 13.0 Gy than after 6.8 Gy. There was a dose-dependent nadir of function at around 8 weeks, followed by a gradual recovery that was complete by about 30 weeks after irradiation, leaving a dose-dependent residual functional deficit. Eccrine sweat glands are very radiosensitive organs compared with the epidermis. A single dose of 13 Gy resulted in complete loss of eccrine gland function at 8 weeks whilst about 23 Gy would be required to elicit transient moist desquamation, in oxygen-breathing mice. Substantial sparing was seen when two doses were split by intervals of up to 24 h.


Asunto(s)
Glándulas Ecrinas/efectos de la radiación , Animales , Relación Dosis-Respuesta en la Radiación , Glándulas Ecrinas/efectos de los fármacos , Pie , Miembro Posterior , Hipohidrosis/etiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Pilocarpina/farmacología , Dosis de Radiación , Traumatismos Experimentales por Radiación/etiología , Elastómeros de Silicona , Piel/efectos de la radiación , Sudor/efectos de los fármacos , Sudor/metabolismo , Sudor/efectos de la radiación , Factores de Tiempo
4.
J Expo Sci Environ Epidemiol ; 21(6): 656-61, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21559054

RESUMEN

Human biomonitoring (analysis of biological fluids) is increasingly being used for assessing exposure to environmental pollutants. Smoking tobacco is a significant source of indoor air pollution and is harmful to human health. The aim of this research was to find both the best non-invasive matrices (from among saliva, urine, semen and sweat) for evaluating environmental exposure to tobacco smoke and the relationships between thiocyanates (biomarkers of environmental tobacco smoke exposure) and other inorganic ions in these matrices collected from active and passive smokers and also non-smokers.


Asunto(s)
Contaminación del Aire Interior/análisis , Líquidos Corporales/efectos de los fármacos , Exposición a Riesgos Ambientales/análisis , Tiocianatos/toxicidad , Contaminación por Humo de Tabaco/análisis , Líquidos Corporales/metabolismo , Estudios de Casos y Controles , Cromatografía por Intercambio Iónico/métodos , Humanos , Compuestos Inorgánicos/análisis , Iones/análisis , Medición de Riesgo/métodos , Saliva/efectos de los fármacos , Saliva/metabolismo , Semen/efectos de los fármacos , Semen/metabolismo , Sudor/efectos de los fármacos , Sudor/metabolismo , Tiocianatos/metabolismo , Orina/química
5.
Integr Environ Assess Manag ; 6(3): 456-68, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20821707

RESUMEN

Ferrochromium alloys are manufactured in large quantities and placed on the global market for use as master alloys (secondary raw materials), primarily for stainless steel production. Any potential human exposure to ferrochromium alloy particles is related to occupational activities during production and use, with 2 main exposure routes, dermal contact and inhalation and subsequent digestion. Alloy and reference particles exposed in vitro in synthetic biological fluids relevant for these main exposure routes have been investigated in a large research effort combining bioaccessibility; chemical speciation; and material, surface, and particle characteristics. In this paper, data for the dermal exposure route, including skin and eye contact, will be presented and discussed. Bioaccessibility data have been generated for particles of a ferrochromium alloy, stainless steel grade AISI 316L, pure Fe, pure Cr, iron(II,III)oxide, and chromium(III)oxide, upon immersion in artificial sweat (pH 6.5) and artificial tear (pH 8.0) fluids for various time periods. Measured released amounts of Fe, Cr, and Ni are presented in terms of average Fe and Cr release rates and amounts released per amount of particles loaded. The results are discussed in relation to bulk and surface composition of the particles. Additional information, essential to assess the bioavailability of Cr released, was generated by determining its chemical speciation and by providing information on its complexation and oxidation states in both media investigated. The effect of differences in experimental temperature, 30 degrees C and 37 degrees C, on the extent of metal release in artificial sweat is demonstrated. Iron was the preferentially released element in all test media and for all time periods and iron-containing particles investigated. The extent of metal release was highly pH dependent and was also dependent on the medium composition. Released amounts of Cr and Fe were very low (close to the limit of detection, <0.008% of particles released or dissolved as iron or chromium) for the alloy particles (ferrochromium alloy and stainless steel), the pure Cr particles, and the metal oxide particles. The released fraction of Cr (Cr/[Cr + Fe]) varied with the material investigated, the test medium, and the exposure time and cannot be predicted from either the bulk or the surface composition. Chromium was released as noncomplexed Cr(III) and in addition in very low concentrations (<3 microg/L). Nickel released was under the limit of detection (0.5 microg/L), except for ultrafine stainless steel particles (<10 microg/L). It is evident that media chemistry and material properties from a bulk and surface perspective, as well as other particle characteristics, and the chemical speciation of released metals have to be considered when assessing any potential hazard or risk induced by sparingly soluble metal or alloy particles.


Asunto(s)
Materiales Biomiméticos/metabolismo , Ojo/metabolismo , Metales Pesados/farmacocinética , Piel/metabolismo , Acero Inoxidable/farmacocinética , Sudor/metabolismo , Lágrimas/metabolismo , Disponibilidad Biológica , Cromo/química , Cromo/farmacocinética , Cromo/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Ojo/efectos de los fármacos , Humanos , Internacionalidad , Hierro/química , Hierro/farmacocinética , Hierro/toxicidad , Metales Pesados/química , Metales Pesados/toxicidad , Soluciones Oftálmicas/metabolismo , Óxidos/química , Óxidos/farmacocinética , Óxidos/toxicidad , Tamaño de la Partícula , Piel/efectos de los fármacos , Acero Inoxidable/química , Acero Inoxidable/toxicidad , Propiedades de Superficie , Sudor/efectos de los fármacos , Lágrimas/efectos de los fármacos , Temperatura
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