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1.
J Nutr ; 154(7): 1985-1993, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797482

RESUMEN

BACKGROUND: Carotenoids are fat-soluble phytochemicals with biological roles, including ultraviolet protective functions in skin. Spectroscopic skin carotenoid measurements can also serve as a noninvasive biomarker for carotenoid consumption. Single-nucleotide polymorphisms (SNPs) in metabolic genes are associated with human plasma carotenoid concentrations; however, their relationships with skin carotenoid concentrations are unknown. OBJECTIVES: The objective of this study was to determine the relationship between 13 candidate SNPs with skin and plasma carotenoid concentrations before and after a carotenoid-rich tomato juice intervention. METHODS: In this randomized, controlled trial, participants (n = 80) were provided with lycopene-rich vegetable juice providing low (13.1 mg), medium (23.9 mg), and high (31.0 mg) daily total carotenoid doses for 8 wk. Plasma carotenoid concentrations were measured by high-pressure liquid chromatography, and skin carotenoid score was assessed by reflection spectroscopy (Veggie Meter) at baseline and the end-of-study time point. Thirteen candidate SNPs in 5 genes (BCO1, CD36, SCARB1, SETD7, and ABCA1) were genotyped from blood using PCR-based assays. Mixed models tested the effects of the intervention, study time point, interaction between intervention and study time point, and SNP genotype on skin and plasma carotenoids throughout the study. Baseline carotenoid intake, body mass index, gender, and age are covariates in all models. RESULTS: The genotype of CD36 rs1527479 (P = 0.0490) was significantly associated with skin carotenoid concentrations when baseline and the final week of the intervention were evaluated. Genotypes for BCO1 rs7500996 (P = 0.0067) and CD36 rs1527479 (P = 0.0018) were significant predictors of skin carotenoid concentrations in a combined SNP model. CONCLUSIONS: These novel associations between SNPs and skin carotenoid concentrations expand on the understanding of how genetic variation affects interindividual variation in skin carotenoid phenotypes in humans. This trial was registered at clinicaltrials.gov as NCT03202043.


Asunto(s)
Carotenoides , Jugos de Frutas y Vegetales , Genotipo , Licopeno , Polimorfismo de Nucleótido Simple , Piel , Humanos , Carotenoides/sangre , Carotenoides/metabolismo , Masculino , Femenino , Piel/metabolismo , Piel/química , Adulto , Persona de Mediana Edad , Jugos de Frutas y Vegetales/análisis , Solanum lycopersicum/genética , Solanum lycopersicum/química , Adulto Joven , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/metabolismo , Antígenos CD36/genética , Antígenos CD36/metabolismo , beta-Caroteno 15,15'-Monooxigenasa
2.
J Biomater Appl ; 38(5): 662-669, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37862784

RESUMEN

Hernias occur when part of an organ, typically the intestines, protrudes through a disruption of the fascia in the abdominal wall, leading to patient pain, discomfort, and surgical intervention. Over one million hernia repair surgeries occur annually in the USA, but globally, hernia surgeries can exceed 20 million. Standard practice includes hernia repair mesh to help hold the compromised tissue together, depending on where the fascial disruption is located and the patient's condition. However, the recurrence rate for hernias after using the most common type of hernia mesh, synthetic, is currently high. Physiological-level electrical stimulation (ES) has shown beneficial effects in improving healing in soft tissue regeneration. Piezoelectric materials can produce low-level electrical signals from mechanical loading to help speed healing. Combining the novelty of piezo elements to create an electrically active hernia repair mesh for faster healing prospects is explored in this study through simulated transcutaneous mechanical loading of the piezo element with therapeutic ultrasound. A tissue phantom was developed using Gelatin #0 and Metamucil® to better simulate a clinical application of the therapeutic ultrasound loading modality. The cellular viability of varying ultrasound intensities and temporal effects was analyzed. Overall, minimal cytotoxicity was observed across all experimental groups during the ultrasound intensity and temporal viability studies.


Asunto(s)
Pared Abdominal , Mallas Quirúrgicas , Animales , Ratones , Humanos , Pared Abdominal/cirugía , Herniorrafia , Hernia , Fibroblastos
3.
Environ Toxicol Chem ; 28(5): 1035-42, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19049262

RESUMEN

Zebrafish (Danio rerio) were fed a diet containing a mixture of 11 structurally diverse brominated flame retardants (BFRs) at nominal concentrations of either 1 or 100 nmol/g for up to 42 d, followed by an elimination period of 14 d. Uptake rates and elimination constants for five of the BFRs were calculated from measurements of their concentrations in the male fish during the exposure and elimination phases. Observed uptake efficiencies were highest for 2,4,4'-tribromodiphenyl ether (BDE 28) and 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH) and were lowest for decabromodiphenyl ether (BDE 209). Estimated half-lives for TBECH and 2,4,6-tribromophenol were short (<2 d). Four BFR metabolites were identified in the fish: 2,2',3,4',5',6-Hexabromodiphenyl ether (BDE 149), 2,2',4,4',5,6'-hexabromodiphenyl ether (BDE 154), 2,4,6-tribromoanisole, and 1,2,4,5-hexabromobenzene. These metabolites were still present in the zebrafish after the 14-d elimination period. No relationship between the BFR concentrations in the zebrafish and their log octanol-water partition coefficient (Kow) values was found. Generally, low tendencies to bioaccumulate were observed for perbrominated and hydroxylated compounds. The observed accumulation of BFR metabolites in fish, however, shows that low concentration of a BFR does not provide, in isolation, a sound indication that the BFR poses low risks.


Asunto(s)
Retardadores de Llama/metabolismo , Éteres Difenilos Halogenados/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Biotransformación , Dieta , Relación Dosis-Respuesta a Droga , Retardadores de Llama/administración & dosificación , Retardadores de Llama/farmacocinética , Éteres Difenilos Halogenados/administración & dosificación , Éteres Difenilos Halogenados/farmacocinética , Estructura Molecular , Relación Estructura-Actividad , Contaminantes Químicos del Agua/administración & dosificación , Contaminantes Químicos del Agua/farmacocinética , Pez Cebra
4.
Chemosphere ; 73(2): 203-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18514256

RESUMEN

In many species reproduction and embryonic development have been shown to be sensitive to environmental contaminants. Understanding embryonic exposure to environmental contaminants is thus highly important. In this study concentrations of brominated flame retardants (BFRs) were measured in zebrafish eggs after parental exposure for 42 days via the diet. Zebrafish were exposed to two doses of eleven structurally-diverse BFRs. Eight BFRs were detected in the female zebrafish and maternal transfer to eggs was evident for all eight compounds. The highest concentrations in eggs were observed for hexabromocyclododecane (HBCD) and 2,4,4'-tribromodiphenyl ether (BDE 28), followed by 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE 183) and tetrabromobisphenol A 2,3-dibromopropyl ether (TBBPA DBPE). Five potential BFR metabolites were tentatively identified in female fish and maternal transfer was observed also for these compounds. The lipid adjusted concentrations in eggs were significantly higher than the concentrations in female fish for several of the BFRs. Further, the results showed a generally higher transfer in the lower exposure level and also indicated a dependency on the physico-chemical properties of the compounds.


Asunto(s)
Retardadores de Llama/análisis , Hidrocarburos Bromados/análisis , Exposición Materna , Animales , Embrión no Mamífero/metabolismo , Femenino , Éteres Difenilos Halogenados/análisis , Óvulo/metabolismo , Contaminación Química del Agua/análisis , Pez Cebra
5.
Ecol Appl ; 16(2): 440-51, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16711035

RESUMEN

Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural production, and also should be considered in the ongoing process of tripling the area of protected habitats in Madagascar.


Asunto(s)
Conservación de los Recursos Naturales , Productos Agrícolas , Polen/fisiología , Semillas/fisiología , Árboles , Animales , Abejas/fisiología , Ecosistema , Humanos , Lemur/fisiología , Madagascar , Modelos Teóricos
6.
Sci Total Environ ; 366(2-3): 638-48, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16540152

RESUMEN

Studies have shown that adult female perch in a freshwater lake, Molnbyggen, Sweden, have a reproductive disorder caused by unidentified endocrine disrupting compounds (EDCs) leaching from a local refuse dump. The adverse effects include shallow open sores, low ratio of sexually mature individuals, low gonadosomatic index and low circulating levels of androgens. We hypothesised that the low androgen levels could be a result of impaired production and/or stimulated excretion of androgens by EDCs. From October 2000 to November 2001, at time-points important in the perch reproductive cycle, adult female perch were collected in Molnbyggen and in the reference lake, Djursjön. The activities of three key enzymes in androgen biosynthesis: 17alpha-hydroxylase (17OHlase), 17,20-lyase (lyase) and 17beta-hydroxysteroid dehydrogenase (17betaHSD) were determined in head kidney or ovary. The relationship between enzyme activities and plasma steroid concentrations was examined. Ovarian histopathology and the determination of brain aromatase activity were also included in the study. Similar 17OHlase, 17betaHSD and aromatase activities were found in Molnbyggen females and reference fish throughout the year. Head kidney 17OHlase showed a positive correlation to cortisol levels (r=0.754; p<0.001) but not to androgen levels. Molnbyggen females exhibited lower ovarian lyase activity during vitellogenesis than reference fish. Atretic oocytes were on most occasions more frequent in sexually immature than in sexually mature females. The results suggest that neither 17OHlase, 17betaHSD nor aromatase is the target for EDCs disrupting the androgen homeostasis of exposed female perch. Further investigation is needed to establish the role of decreased ovarian lyase activity in endocrine homeostasis, but the possibility of increased excretion of androgens should also be examined.


Asunto(s)
Disruptores Endocrinos/toxicidad , Percas/metabolismo , Eliminación de Residuos , Esteroide 17-alfa-Hidroxilasa/metabolismo , Contaminantes Químicos del Agua/toxicidad , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Animales , Aromatasa/metabolismo , Biomarcadores , Encéfalo/enzimología , Femenino , Hormonas Esteroides Gonadales/sangre , Riñón/enzimología , Ovario/enzimología
7.
Med Sci Sports Exerc ; 35(4): 617-22, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12673145

RESUMEN

INTRODUCTION/PURPOSE: Despite a large public health interest in physical activity and its role in obesity and other chronic diseases, only few reports to date have addressed total levels and trends of physical activity. We have studied in a cross-sectional setting with a retrospective recall of physical activity an association of levels of total physical activity and different types of activities with age and with calendar-time. METHODS: In a population-based study of 33,466 men aged 45-79 yr in central Sweden, information on physical activity and other lifestyle factors was collected through a self-administered questionnaire. Level of total activity at ages 15, 30, and 50 yr was assessed quantitatively, based on six questions on different activities: work/occupation, housework, walking/bicycling, exercise, inactive leisure time, and sleeping. The physical activity levels were measured as metabolic equivalents, MET-hours per days. RESULTS: Total daily physical activity decreased at age 30 yr (-1.6%, 95% CI: -1.7, -1.4) and at age 50 yr (-3.9%, 95% CI: -4.0, -3.7) compared with age 15 yr. Total physical activity decreased over a period of 60 yr in all three separate age groups (-9.1% among 15-yr-olds, 95% CI: -9.8, -8.5; -2.3% among 30-yr-olds 95% CI: -3.0, -1.6; and -2.9% among 50-yr-olds, 95% CI: -3.4, -2.5). CONCLUSION: These negative trends in physical activity observed by age and with time might explain the trends in increasing prevalence of obesity.


Asunto(s)
Ejercicio Físico , Aptitud Física , Factores de Edad , Anciano , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Ocupaciones , Salud Pública , Estudios Retrospectivos , Deportes , Suecia
8.
Acta Obstet Gynecol Scand ; 85(1): 63-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16521682

RESUMEN

BACKGROUND: Quality of perinatal care was evaluated in relation to size of delivery unit and size of catchment area for deliveries. METHODS: Neonatal outcome, measured as neonatal mortality, low Apgar scores at 5 min, and the occurrence of respiratory disorders and cerebral palsy was analyzed during a 15-year period from 1985 to 1999 inclusive. Figures were derived from the Swedish Medical Birth Registry and the Hospital Discharge Registry. Odds ratios were estimated for the different outcomes in relation to size of delivery unit (actual and estimated number of births) and the provision of a pediatric department at the hospital. Seven possible confounders were considered: year of birth, maternal age, parity, smoking during pregnancy, gestational age, parental cohabitation, and maternal body mass index. RESULTS: Neonatal mortality was significantly higher for infants in families living within the catchment area of the smallest units without a pediatric department. Small differences in the occurrence of respiratory disturbances and Apgar scores are probably due to diagnostic differences. There were no differences in the incidence of cerebral palsy. Neonatal mortality continued to decrease during the observation period. CONCLUSIONS: Differences were minor, pointing to a fairly homogeneous quality of perinatal care and an efficient referral system for risk pregnancies. Mortality continues to decrease in spite of a reduction in the number of units caring for deliveries.


Asunto(s)
Tasa de Natalidad , Unidades Hospitalarias , Evaluación de Resultado en la Atención de Salud , Adulto , Áreas de Influencia de Salud , Femenino , Edad Gestacional , Humanos , Mortalidad Infantil , Recién Nacido , Embarazo , Sistema de Registros , Suecia/epidemiología
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