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1.
Sci Rep ; 11(1): 7791, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33833353

RESUMO

The feasibility and surgical effort of a pre-lacrimal window approach (PLWA) depends on the width of the bony window anterior to the nasolacrimal duct. This study aimed to investigate gender-specific differences in feasibility of PLWA. A consecutive series of paranasal computed tomography scans from 50 females (n = 100) and 50 males (n = 100) were retrospectively analyzed. The primary outcome measure was the antero-posterior length of the bony pre-lacrimal window (BPLWA). The secondary outcome measure was the distribution of Simmen's PLWA feasibility types (major, moderate and minor surgical effort). On average, males had a 1.5 mm (95% CI 0.8-2.2) significantly higher BPLW length in comparison to females [t(198) = 4.4, p < 0.0001]. The requirement of major surgical effort occurred 29% more frequently in females [χ2(1) = 17.7, p < 0.0001], whereas the necessity of moderate surgical effort was 21% more prevalent in males [χ2(1) = 8.8, p = 0.003]. The need of only minor surgical effort was twice as high in males compared to females [χ2(1) = 3, p = 0.081]. Our data indicates that females require more significant surgical effort during a PLWA to gain access to the maxillary sinus. These results are highly informative as a high amount of bone removal and nasolacrimal duct dislocation are associated with a higher likelihood of complications.


Assuntos
Seio Maxilar/diagnóstico por imagem , Ducto Nasolacrimal/diagnóstico por imagem , Fatores Sexuais , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Humanos , Masculino , Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Ducto Nasolacrimal/cirurgia , Estudos Retrospectivos
4.
Clin Otolaryngol ; 43(4): 1050-1056, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29575651

RESUMO

OBJECTIVES: Reliable prognostic markers are lacking for tongue carcinoma. C-reactive protein (CRP) and a ratio from neutrophils/lymphocytes (NLR) are biomarkers, associated with prognosis in solid cancers. Aim of this work was to investigate the role of CRP and NLR in prognosis of patients with tongue carcinoma. DESIGN: Retrospective cohort study. SETTING: We retrospectively analysed data of patients treated for tongue carcinoma at our institution. Levels of CRP, Neutrophils and Lymphocytes were measured pretherapeutic. PARTICIPANTS: 197 patients treated for squamous cell carcinoma of the tongue between 2002 and 2015. MAIN OUTCOME MEASURES: Overall survival, disease-free survival. RESULTS: Elevated CRP was significantly associated with shorter overall survival in our cohort in uni- and multivariate analysis. NLR was not associated with prognosis. CONCLUSION: In the present study we could confirm the role of CRP as an independent prognostic marker in patients with tongue carcinoma. Incorporating this marker in prognostication could represent a valuable and moreover inexpensive tool for improved decisions making concerning therapy in the future.

5.
Handchir Mikrochir Plast Chir ; 48(5): 253-9, 2016 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-27580437

RESUMO

Congenital thumb hypoplasia is a radial deficiency occurring in the form of sole dysplasia or in combination with additional aberrations. Thumb hypoplasia can be categorised into 5 grades ranging from mild deformity to complete absence of the thumb. Thumb hypoplasia leads to a disturbance of grip function depending on its severity. The choice of treatment is based on the degree of thumb hypoplasia. For hypoplasia greater than grade 3B, restoration of the thumb using pollicization of the index finger is the treatment of choice. For this purpose the index finger is transformed into a thumb and is transposed to the position of the thumb with vessels and nerves being retained. The skeleton has to be shortened, rotated and abducted, followed by reconstruction of the muscles in line with the function of the new thumb. This procedure facilitates a restoration with maximal stability, sensitivity and mobility. In cases of isolated thumb hypoplasia, pollicization of the index finger yields good results persisting into adulthood. If associated aberrations are present, the outcome is less predictable because of the preexistent stiffness of the index finger. Nevertheless, associated aberrations do not represent a contraindication for index finger pollicization.


Assuntos
Dedos/cirurgia , Deformidades da Mão , Procedimentos de Cirurgia Plástica , Polegar/cirurgia , Humanos , Rádio (Anatomia)
6.
Osteoporos Int ; 24(5): 1567-77, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23229471

RESUMO

UNLABELLED: On September 29, 2011, acknowledged experts in the field of vitamin D, mainly European, were brought together in order to discuss the recent scientific advances in relation to vitamin D: the current requirements and associations with various health outcomes. In this article, the discussions resulting from the meeting are summarized. INTRODUCTION: Several groups at risk for developing vitamin D insufficiency have been identified. Accordingly, reviews indicate that a significant percentage of the population worldwide have serum 25-hydroxyvitamin D levels below 50 nmol/l. In addition to the role of vitamin D in bone health, recent studies suggest that it may play a pivotal role in other systems, e.g., the cardiovascular system, pancreas, muscle, immune system and brain. Most evidence, however, is obtained from observational studies and yet inconclusive. METHODS: To exchange and broaden knowledge on the requirements for vitamin D and its effect on various health outcomes, a workshop entitled "Vitamin D Expert Meeting: Do we get enough?", was organized. RESULTS: Despite low vitamin D levels worldwide, consensus on the definition of deficiency is not yet reached. In order to define cut-off points for vitamin D whilst taking into account extraskeletal health effects, randomized controlled trials in these fields are warranted. The experts do emphasize that there is evidence to suggest an important role for vitamin D in the maintenance of optimal bone health at all ages and that vitamin D supplementation, in most studies co-administered with calcium, reduces fracture risk in the senior population. CONCLUSION: To reach a serum 25-hydroxyvitamin D level of 50 nmol/l older adults aged ≥65 years are therefore recommended to meet a mean daily vitamin D intake of 20 µg (800 IU), which is best achieved with a supplement.


Assuntos
Dieta/normas , Suplementos Nutricionais , Deficiência de Vitamina D/diagnóstico , Vitamina D/administração & dosagem , Europa (Continente) , Medicina Baseada em Evidências/métodos , Saúde Global , Humanos , Valores de Referência , Luz Solar , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue
8.
Mol Psychiatry ; 14(11): 1040-50, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18362913

RESUMO

There is an increasing interest in the underlying mechanisms of the antidepressant and anxiolytic treatment effect associated with changes in serotonergic neurotransmission after treatment with selective serotonin (5-HT) reuptake inhibitors (SSRIs) in humans. The 5-HT(1A) receptor is known to play a crucial role in the pathophysiology of affective disorders, and altered 5-HT(1A) receptor binding has been found in anxiety patients. SSRI treatment raises the 5-HT level in the synaptic cleft and might change postsynaptic receptor densities. Therefore, our study in patients suffering from anxiety disorders investigated the effects of long-term treatment with escitalopram on the 5-HT(1A) receptor. A longitudinal positrone emission tomography (PET) study in 12 patients suffering from anxiety disorders was conducted. Two dynamic PET scans were performed applying the selective 5-HT(1A) receptor antagonist [carbonyl-(11)C]WAY-100635. Eight regions of interest were defined a priori (orbitofrontal cortex, amygdala, hippocampus, subgenual cortex, anterior and posterior cingulate cortex, dorsal raphe nucleus and cerebellum as reference). After the baseline PET scan, patients were administered escitalopram (average dose of 11.2+/-6.0 mg day(-1)) for a minimum of 12 weeks. A second PET scan was conducted after 109+/-27 days. 5-HT(1A) receptor binding potentials in 12 patients were assessed by PET applying the Simplified Reference Tissue Model.There was a significant reduction in the 5-HT(1A) receptor binding potential after a minimum of 12 weeks of escitalopram treatment in the hippocampus (P=0.006), subgenual cortex (P=0.017) and posterior cingulate cortex (P=0.034). The significance of the hippocampus region survived the Bonferroni-adjusted threshold for multiple comparisons. These PET data in humans in vivo demonstrate a reduction of the 5-HT(1A) binding potential after SSRI treatment.


Assuntos
Antidepressivos de Segunda Geração/farmacologia , Antidepressivos de Segunda Geração/uso terapêutico , Ansiedade , Citalopram/farmacologia , Citalopram/uso terapêutico , Sistema Límbico/efeitos dos fármacos , Receptor 5-HT1A de Serotonina/metabolismo , Adulto , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Ansiedade/patologia , Mapeamento Encefálico , Isótopos de Carbono/metabolismo , Estudos de Casos e Controles , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Humanos , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/metabolismo , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Piperazinas/metabolismo , Piperazinas/farmacologia , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica/efeitos dos fármacos , Piridinas/metabolismo , Piridinas/farmacologia , Antagonistas da Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Fatores de Tempo , Adulto Jovem
9.
Bone ; 40(1): 37-44, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16949896

RESUMO

Quantitative ultrasound (QUS) measurements at peripheral sites can be used to estimate osteoporotic fracture risk. However, measurements at these sites are less suitable to predict bone mineral density (BMD) or fracture risk at the central skeleton. We investigated whether direct QUS measurements at the femur would allow to estimate dual X-ray absorptiometry (DXA) BMD of the total proximal femur with errors comparable to established DXA accuracy errors. Two independent sets of femora were measured in Kiel (6 f, 4 m, age: 55-90) and Paris (19 f, 20 m age: 45-95) using different benchtop systems in the two laboratories. The femora were scanned in transverse transmission mode using focused US transducers of 500 kHz center frequency. The QUS values were averaged over a region similar to the total hip region of dual X-ray absorptiometry (DXA) measurements. BMD was measured using DXA. SOS and BMD correlated significantly (p<0.0001) in both data sets (R2=0.81-0.93). Correlations between BUA and BMD were also significant at p<0.001, but correlation coefficients were lower (R2=0.61-0.75). Residual errors for the estimation of BMD were 8%-10% for SOS as predictor, and 14%-16% for BUA as predictor. The residual error of 8 to 10% for the estimation of BMD from SOS is comparable to variabilities among different DXA femur subregions and accuracy errors of femoral DXA measurements caused by the impact of soft tissue. It is substantially smaller than the errors of 13% for the estimation of total femur BMD from spine BMD, 14% for the estimation of total femur BMD from calcaneus SOS or 16% for the estimation of ash weight from DXA. The results of the study show that SOS is able to predict total BMD with adequate accuracy. If femoral BMD could be obtained in vivo with comparable accuracy, femoral QUS would be suited for the assessment of bone status at one of the main osteoporotic fracture sites.


Assuntos
Densidade Óssea , Fêmur/diagnóstico por imagem , Ultrassonografia/normas , Absorciometria de Fóton , Cadáver , Feminino , Humanos , Ultrassom
10.
Calcif Tissue Int ; 77(3): 186-92, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16151672

RESUMO

Bone mineral density (BMD) measured with dual energy X-ray absorptiometry (DXA) techniques is the current gold standard for osteoporotic fracture risk prediction. Quantitative ultrasound (QUS) techniques in transmission measurements are, however, increasingly recognized as an alternative approach. It is feasible to select different QUS methods, one type being optimized to assess microarchitectural properties of bone structure and another to assess BMD. Broadband ultrasonic attenuation (BUA) and ultrasonic velocity (UV) measured on the proximal human femur have been shown to be both significantly correlated with BMD. However, a great diversity of algorithms has been reported to measure the time-of-flight used to derive UV values. The purpose of this study was to determine which procedure results in the optimal BMD prediction at the proximal femur from ultrasound measurements. Thirty-eight excised human femurs were measured in transmission with a pair of focused 0.5-MHz central frequency transducers. Two-dimensional scans were performed and radiofrequency (RF) signals were recorded digitally at each scan position. BUA was estimated and eight different signal processing techniques were performed to estimate UV. For each signal-processing technique UV was compared to BMD. We show that the best prediction of BMD was obtained with signal-processing techniques taking into account only the first part of the transmitted signal (r2BMD-SOS = 0.86). Moreover, we show that a linear multiple regression using both BUA and speed of sound (SOS) and applied to site-matched regions of interest improved the accuracy of BMD predictions (r2BMD-SOS/BUA = 0.95). Our results demonstrate that selecting specific signal-processing methods for QUS variables allows optimal assessment of BMD. Correlation is sufficiently high that this specific QUS method can be considered as a good surrogate of BMD.


Assuntos
Densidade Óssea , Fêmur/diagnóstico por imagem , Fêmur/metabolismo , Ultrassonografia/métodos , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Ultrassonografia/instrumentação
11.
Praxis (Bern 1994) ; 91(1-2): 7-16, 2002 Jan 09.
Artigo em Alemão | MEDLINE | ID: mdl-11824146

RESUMO

Periconceptional use of folic acid reduces the risk of neural tube defects considerably. In Switzerland, implementation of these findings could be improved through fortification of a staple food with folic acid. The present paper reviews possible hazards associated with high intake of folic acid in the general population. Among the potential safety issues are interaction between folic acid and zinc, interaction between folic acid and drugs (phenytoin, methotrexate etc.) and hypersensitivity to folic acid. Of main concern are adverse effects of folic acid in cobalamin deficiency. Solutions are discussed.


Assuntos
Ácido Fólico/administração & dosagem , Ácido Fólico/efeitos adversos , Adulto , Animais , Anticonvulsivantes/metabolismo , Antirreumáticos/metabolismo , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Estudos de Casos e Controles , Criança , Estudos de Coortes , Método Duplo-Cego , Hipersensibilidade a Drogas/etiologia , Interações Medicamentosas , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Feminino , Antagonistas do Ácido Fólico/metabolismo , Humanos , Recém-Nascido , Masculino , Metotrexato/metabolismo , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Placebos , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Fatores de Tempo , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Zinco/sangue , Zinco/metabolismo
12.
J Am Coll Nutr ; 20(3): 232-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11444419

RESUMO

OBJECTIVE: The objective of this study was to determine the effect of individual carotenoid supplementation on biochemical indices of oxidative status in apparently healthy adult males. METHODS: The study was a placebo controlled single blind study. Healthy male volunteers (n= 175) were assigned to four groups. They received daily supplements of beta-carotene (15 mg), lutein (15 mg), lycopene (15 mg) and placebo for three months. The effects of the supplementation on antioxidant status were monitored by plasma carotenoid, vitamin C and A levels, glutathione (GSH and GSSG) concentrations, protein SH groups. erythrocyte antioxidant enzyme activities (Cu-Zn SOD, Se-GSH-Px) and susceptibility of LDL to copper-induced oxidation. RESULTS: beta-carotene, lycopene and lutein supplementation led to significant plasma and LDL increases in each of these carotenoids, without modifications of other carotenoid levels in plasma or in LDL. The supplementation failed to enhance the resistance of LDL to oxidation or to modify the LDL polyunsaturated/ saturated fatty acid ratio. Vitamin C, GSH, protein SH groups and antioxidant metalloenzyme activities were also unchanged. CONCLUSION: We did not observe beneficial or adverse effects of lutein, lycopene or beta-carotene supplementation on biomarkers of oxidative stress. In apparently healthy subjects, carotenoid supplementation does not lead to significantly measurable improvement in antioxidant defenses.


Assuntos
Antioxidantes/administração & dosagem , Carotenoides/administração & dosagem , Lipoproteínas LDL/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Carotenoides/sangue , Suplementos Nutricionais , Humanos , Peroxidação de Lipídeos , Luteína/administração & dosagem , Luteína/sangue , Licopeno , Masculino , Oxirredução , beta Caroteno/administração & dosagem , beta Caroteno/sangue
14.
Swiss Med Wkly ; 131(37-38): 539-49, 2001 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-11759174

RESUMO

It is only recently that folate deficiency has been implicated in the development of cancer. The mechanisms by which folate might protect against cancer are not clear but may relate to its role in DNA methylation and DNA synthesis. All case-control, cohort and intervention trials reported in English, French, or German, on folate intake or blood levels in relation to the risk of colorectal, breast, and cervix cancer were reviewed. Twenty case-control, and 12 nested case-control or cohort studies were identified. The epidemiological studies consistently show an inverse association between intake and/or levels of folate and the frequency of colorectal carcinomas, and less clearly of adenomas. Long-term use of supplements of folate seems to be of greater benefit than dietary intake. The effect of folate seems to be modulated by alcohol, methionine, and MTHFR polymorphisms. Results from animal studies suggest that folate supplementation might decrease or increase cancer risk depending on dosage and timing. Recent studies also suggest an inverse association between folate intake and breast cancer among women who regularly consume alcohol. Conversely, epidemiological evidence remains uncertain for the role of folate in cervical cancer prevention; the results of two intervention trials on rates of cervical intraepithelial neoplasia regression or progression were negative. An effect of folate later in carcinogenesis is not supported by the few (nested) case-control studies on invasive cervical cancer. Some of the conflicting results may be due to the fact that dietary intake or blood levels of folate do not accurately reflect folate concentrations in the cells of cancer origin. Furthermore, only a few studies have taken into account the modulating effect of alcohol, methionine, and MTHFR polymorphisms in their analyses. The observed inverse associations between folate and risk of cancer, on the other hand, may be confounded by various factors, especially by other potentially protective constituents in fruits and vegetables. Ongoing intervention studies can strengthen evidence for causality by excluding such confounding, but the optimal dose, duration, and stage of carcinogenesis and the appropriate (genetically predisposed) study group for folate chemoprevention are not yet defined.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Deficiência de Ácido Fólico/complicações , Deficiência de Ácido Fólico/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/etiologia , Neoplasias da Mama/fisiopatologia , Neoplasias Colorretais/fisiopatologia , Feminino , Deficiência de Ácido Fólico/fisiopatologia , Humanos , Masculino , Fatores de Risco , Neoplasias do Colo do Útero/fisiopatologia
15.
Int J Vitam Nutr Res ; 70(5): 226-37, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11068703

RESUMO

The purpose of this study was to estimate the intake-plasma relationship for vitamin C by means of a meta-analysis. A MEDLINE search revealed 30 publications matching our inclusion criteria. We completed the set with 5 older papers and with one monograph. The proposed statistical model corrects for inconsistencies with regard to methodological differences between the various studies. Therefore, the contribution of a particular study to the estimation is independent of the number of data points. The estimations were performed for the complete data set as well as for different subgroups: "adult" aged 15-65 years, "elderly" aged 60-96 years, "nonsmokers" and "smokers". The 50th percentile of the plasma concentration for a daily vitamin C intake of 60 mg was 42.4 mumol/L. The corresponding values for the different subgroups were: "adult" 44.1 mumol/L, "elderly" 31.0 mumol/L, "nonsmokers" 42.4 mumol/L, and "smokers" 33.6 mumol/L. Thus, this meta-analysis confirms earlier results that the requirements of vitamin C is higher in "elderly" and "smokers" compared to "adult" and "nonsmokers" and it can be used for the estimation of the vitamin C intake in order to achieve a desired plasma level within a target population. In the general population the assumed optimal plasma concentration of 50 mumol/L, as proposed by a consensus conference, can be achieved by the intake of 100 mg per day, which is the new recommendation of the Austrian, German, and Swiss Nutrition Societies.


Assuntos
Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Estado Nutricional , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/fisiologia , Teorema de Bayes , Dieta , Humanos , MEDLINE , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Estatísticos , Necessidades Nutricionais , Fumar
17.
Chemosphere ; 40(6): 641-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10705540

RESUMO

PCDD/PCDF were determined in solid samples from wood combustion. The samples included grate ashes, bottom ashes, furnace ashes as well as fly and cyclone ashes. The solid waste samples were classified into bottom and fly ash from native wood and bottom and fly ash from waste wood. For each of the four classes concentration distribution patterns from individual congeners, the sums of PCDD/PCDF and the international toxicity equivalents (I-TEQ) values are given. The I-TEQ levels of fly ash from waste wood burning can be approximately up to two thousand times higher than the values from fly ashes of natural wood. The I-TEQ levels in bottom ashes from waste wood combustion systems are as low as the corresponding ashes from the combustion of native wood. Grate ash samples from waste wood combustion systems with low carbon burnout show high levels of PCDD/PCDF.


Assuntos
Benzofuranos/análise , Espectrometria de Massas/métodos , Dibenzodioxinas Policloradas/análogos & derivados , Madeira , Dibenzofuranos Policlorados , Incineração , Dibenzodioxinas Policloradas/análise , Suíça
18.
Arzneimittelforschung ; 50(1): 11-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10683710

RESUMO

A series of new analogues of the arecaidine propargyl ester (CAS 35516-99-5), APE, 1a) with alcohols consisting of 4 or 5 carbon atoms were investigated at muscarinic receptor subtypes. The muscarinic activity of the quaternary and tertiary salts of the APE-related compounds were assayed on the isolated guinea-pig ileum (M3 receptor subtype) and guinea-pig left atria (M2 receptor subtype) as well as on rabbit isolated vas deferens (M1 receptor subtype). The structural variations made in the APE molecule, replacing the triple bond in the ester side chain with structures such as double bond, an allene moiety, a single bond, a cyclopropyl group or two triple bonds should alter the selectivity and potency in favour of the M2 subtype. Enhanced, though modest, selectivity for M2 receptors was achieved with the 2-butynyl ester 2a. The other structural variations resulted in a loss of potency, but not necessarily of efficacy.


Assuntos
Arecolina/análogos & derivados , Colinérgicos/farmacologia , Animais , Arecolina/química , Arecolina/farmacologia , Colinérgicos/síntese química , Feminino , Cobaias , Coração/efeitos dos fármacos , Íleo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Coelhos , Receptor Muscarínico M1 , Receptor Muscarínico M2 , Receptor Muscarínico M3 , Receptores Muscarínicos/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos
19.
Int J Vitam Nutr Res ; 69(5): 356-61, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10526781

RESUMO

Many studies and scientific publications report on potentially beneficial effects of the lipophilic anti-oxidant vitamin E on cellular metabolic pathways. The present work presents data on the influence of tocopherol on different intracellular parameters of intact and living human skin fibroblasts by flow-cytometric measurements. The parameters analysed were the intracellular pH, representing cell metabolism and cell function, intracellular glutathione, representing one of the cell's own radical scavenger enzyme systems, membrane potential and cell viability. In order to cause large numbers of free radicals cells were UVB-irradiated prior to measurement. The results of the flow-cytometric measurements indicate that vitamin E has significant protecting effects on the measured biochemical parameters during oxidative stress. In the presence of the lipophilic radical scavenger a significant stabilizing effect on pH, intracellular glutathione levels and membrane potential could be observed. Furthermore, vitamin E administration was associated with increased cell viability after UVB irradiation.


Assuntos
Antioxidantes/farmacologia , Fibroblastos/metabolismo , Estresse Oxidativo , Vitamina E/farmacologia , Separação Celular , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Citometria de Fluxo , Glutationa/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Potenciais da Membrana , Pele/metabolismo
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