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1.
Chem Phys Lipids ; 225: 104816, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31525381

RESUMEN

To optimize dermal and transdermal administration of drugs, the barrier function of the skin, particularly the stratum corneum (SC), needs to be reduced reversibly. For this purpose, penetration/diffusion enhancers such as DMSO can be applied. However, there is the question whether DMSO is an aggressive penetration/diffusion enhancer in pharmaceutical and cosmetical relevant concentrations? Until now, it is unclear if this penetration/diffusion enhancement is caused by an interaction with the SC lipid matrix or related to effects within the corneocytes. Therefore, the effects of the hydrophilic enhancer DMSO on SC models with different dimensionality ranging from bilayers (liposomes) via oligo-layers to multilayers have been investigated in this study. The effects of DMSO should be compared to that of other relevant hydrophilic enhancers such as urea and taurine. An innovative spectrum of methods was applied to ascertain the mode of action of DMSO in relevant concentrations on a molecular scale. The experiments reveal that there is no specific interaction of 10% and 30% DMSO solutions with the SC model systems. Hence, if DMSO is applied in pharmaceutically and cosmetically relevant concentrations, it has no influence on the SC model systems used. Neither an additional water uptake in the head group region nor a decrease of the lipid chain packing density have been observed. The leakage studies on liposomes show that 10% DMSO is causing just a very slight leakage of 8%, lower than the leakage of 19.4% caused by 10% urea (Müller et al., 2016). Consequently, the interactions of DMSO with the SC model lipids used are very low in concentrations of 10% and 30%, respectively. Since the lipid composition in native SC lipid matrix is far more complex than this model mixture, the results can not be directly transferred to the native SC lipid matrix. However, the outcome of this study, together with various findings in the literature give rise to the assumption that the enhancing effect of DMSO concerning the diffusion of relevant hydrophilic drugs and actives appears to be realized via the corneocytes.


Asunto(s)
Dimetilsulfóxido/química , Lípidos/química , Óxido de Deuterio/química , Difusión , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Liposomas/química , Modelos Moleculares , Tamaño de la Partícula , Propiedades de Superficie
2.
Braz J Med Biol Res ; 52(7): e8429, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31314852

RESUMEN

The present study aimed to analyze age-related changes to motor coordination, balance, spinal cord oxidative biomarkers in 3-, 6-, 18-, 24-, and 30-month-old rats. The effects of low-intensity exercise on these parameters were also analyzed in 6-, 18-, and 24-month-old rats. Body weight, blood glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were assessed for all rats. The soleus muscle weight/body weight ratio was used to estimate skeletal muscle mass loss. Body weight increased until 24 months; only 30-month-old rats exhibited decreased blood glucose and increased total cholesterol and HDL cholesterol. The soleus muscle weight/body weight ratio increased until 18 months, followed by a small decrease in old rats. Exercise did not change any of these parameters. Stride length and step length increased from adult to middle age, but decreased at old age. Stride width increased while the sciatic functional index decreased in old rats. Performance in the balance beam test declined with age. While gait did not change, balance improved after exercise. Aging increased superoxide anion generation, hydrogen peroxide levels, total antioxidant capacity, and superoxide dismutase activity while total thiol decreased and lipid hydroperoxides did not change. Exercise did not significantly change this scenario. Thus, aging increased oxidative stress in the spinal cord, which may be associated with age-induced changes in gait and balance. Regular low-intensity exercise is a good alternative for improving age-induced changes in balance, while beneficial effects on gait and spinal cord oxidative biomarkers cannot be ruled out because of the small number of rats investigated (n=5 or 6/group).


Asunto(s)
Factores de Edad , Biomarcadores/sangre , Marcha/fisiología , Estrés Oxidativo/fisiología , Condicionamiento Físico Animal/fisiología , Equilibrio Postural/fisiología , Médula Espinal/fisiología , Animales , Biomarcadores/metabolismo , Glucemia/análisis , Peso Corporal/fisiología , Colesterol/sangre , Lipoproteínas HDL/sangre , Masculino , Ratas , Ratas Wistar , Médula Espinal/metabolismo
3.
Braz. j. med. biol. res ; 52(7): e8429, 2019. graf
Artículo en Inglés | LILACS | ID: biblio-1011597

RESUMEN

The present study aimed to analyze age-related changes to motor coordination, balance, spinal cord oxidative biomarkers in 3-, 6-, 18-, 24-, and 30-month-old rats. The effects of low-intensity exercise on these parameters were also analyzed in 6-, 18-, and 24-month-old rats. Body weight, blood glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were assessed for all rats. The soleus muscle weight/body weight ratio was used to estimate skeletal muscle mass loss. Body weight increased until 24 months; only 30-month-old rats exhibited decreased blood glucose and increased total cholesterol and HDL cholesterol. The soleus muscle weight/body weight ratio increased until 18 months, followed by a small decrease in old rats. Exercise did not change any of these parameters. Stride length and step length increased from adult to middle age, but decreased at old age. Stride width increased while the sciatic functional index decreased in old rats. Performance in the balance beam test declined with age. While gait did not change, balance improved after exercise. Aging increased superoxide anion generation, hydrogen peroxide levels, total antioxidant capacity, and superoxide dismutase activity while total thiol decreased and lipid hydroperoxides did not change. Exercise did not significantly change this scenario. Thus, aging increased oxidative stress in the spinal cord, which may be associated with age-induced changes in gait and balance. Regular low-intensity exercise is a good alternative for improving age-induced changes in balance, while beneficial effects on gait and spinal cord oxidative biomarkers cannot be ruled out because of the small number of rats investigated (n=5 or 6/group).


Asunto(s)
Animales , Masculino , Ratas , Condicionamiento Físico Animal/fisiología , Biomarcadores/sangre , Factores de Edad , Estrés Oxidativo/fisiología , Equilibrio Postural/fisiología , Marcha/fisiología , Médula Espinal/fisiología , Médula Espinal/metabolismo , Glucemia/análisis , Peso Corporal/fisiología , Biomarcadores/metabolismo , Colesterol/sangre , Ratas Wistar , Lipoproteínas HDL/sangre
4.
Braz. j. biol ; 78(3): 464-471, Aug. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-951584

RESUMEN

Abstract The fish may experience periods of food deprivation or starvation which produce metabolic changes. In this study, adult Rhamdia quelen males were subjected to fasting periods of 1, 7, 14, and 21 days and of refeeding 2, 4, 6, and 12 days. The results demonstrated that liver protein was depleted after 1 day of fasting, but recovered after 6 days of refeeding. After 14 days of fasting, mobilization in the lipids of the muscular tissue took place, and these reserves began to re-establish themselves after 4 days of refeeding. Plasmatic triglycerides increased after 1 day of fasting, and decreased following 2 days of refeeding. The glycerol in the plasma oscillated constantly during the different periods of fasting and refeeding. Changes in the metabolism of both protein and lipids during these periods can be considered as survival strategies used by R. quelen. The difference in the metabolic profile of the tissues, the influence of the period of fasting, and the type of reserves mobilized were all in evidence.


Resumo Os peixes podem sofrer períodos de privação de alimentos ou de fome, que produzem mudanças metabólicas. Neste estudo, jundiás machos adultos foram submetidos a jejum períodos de 1, 7, 14 e 21 dias e realimentação 2, 4, 6, e 12 dias. Os resultados demonstraram que a proteína do fígado foi esgotada depois de um dia de jejum, mas restabeleceu após 6 dias de realimentação. Após 14 dias de jejum, ocorreu a mobilização dos lípidos no tecido muscular sendo que estas reservas começaram a re-estabelecer-se após 4 dias de realimentação. Os triglicérides plasmáticos aumentam após um dia de jejum, e diminuiram após 2 dias de realimentação. O glicerol no plasma oscilou constantemente durante os diferentes períodos de jejum e realimentação. As alterações no metabolismo de proteína e lipídios durante estes períodos podem ser consideradas uma estratégias de sobrevivência utilizada pelo Rhamdia quelen. Sendo que a diferença no perfil metabólico tecidual bem como a influência do período de jejum e o tipo de reserva a ser mobilizada foram observadas neste estudo.


Asunto(s)
Animales , Masculino , Bagres/fisiología , Ayuno/fisiología , Metabolismo Energético/fisiología , Metabolismo de los Lípidos/fisiología , Conducta Alimentaria , Adaptación Fisiológica , Ayuno/metabolismo , Glucógeno/metabolismo , Lípidos/sangre , Alimentación Animal , Músculos
5.
Biochim Biophys Acta Gen Subj ; 1862(8): 1742-1750, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29753114

RESUMEN

We investigated the insertion of small potassium (K+) channel proteins (KcvMA-1D and KcvNTS) into model membranes and the lipid-protein structural interference, combining neutron reflectometry and electrophysiology. Neutron reflectometry experiments showed how the transverse structure and mechanical properties of the bilayer were modified, upon insertion of the proteins in single model-membranes, either supported on solid substrate or floating. Parallel electrophysiology experiments were performed on the same channels reconstituted in free-standing planar lipid bilayers, of both typical composition and matched to the neutron reflectometry experiment, assessing their electrical features. Functional and structural results converge in detecting that the proteins, conical in shape, insert with a directionality, cytosolic side first. Our work addresses the powerful combination of the two experimental approaches. We show here that membrane structure spectroscopy and ion channel electrophysiology can become synergistic tools in the analysis of structural-functional properties of biomimetic complex environment.


Asunto(s)
Electrofisiología , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Fosfolípidos/química , Pichia/metabolismo , Canales de Potasio/química , Canales de Potasio/metabolismo , Activación del Canal Iónico , Difracción de Neutrones , Conformación Proteica
6.
Braz J Biol ; 78(3): 464-471, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29091116

RESUMEN

The fish may experience periods of food deprivation or starvation which produce metabolic changes. In this study, adult Rhamdia quelen males were subjected to fasting periods of 1, 7, 14, and 21 days and of refeeding 2, 4, 6, and 12 days. The results demonstrated that liver protein was depleted after 1 day of fasting, but recovered after 6 days of refeeding. After 14 days of fasting, mobilization in the lipids of the muscular tissue took place, and these reserves began to re-establish themselves after 4 days of refeeding. Plasmatic triglycerides increased after 1 day of fasting, and decreased following 2 days of refeeding. The glycerol in the plasma oscillated constantly during the different periods of fasting and refeeding. Changes in the metabolism of both protein and lipids during these periods can be considered as survival strategies used by R. quelen. The difference in the metabolic profile of the tissues, the influence of the period of fasting, and the type of reserves mobilized were all in evidence.


Asunto(s)
Bagres/fisiología , Metabolismo Energético/fisiología , Ayuno/fisiología , Conducta Alimentaria , Metabolismo de los Lípidos/fisiología , Adaptación Fisiológica , Alimentación Animal , Animales , Ayuno/metabolismo , Glucógeno/metabolismo , Lípidos/sangre , Masculino , Músculos
7.
Phys Chem Chem Phys ; 19(45): 30636-30646, 2017 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-29116265

RESUMEN

This work addresses the pH-triggered distribution and relocation of charge-stabilized gold nanoparticles (AuNPs) incorporated into strong polyelectrolyte brushes. Brush/particle composite materials were investigated under aqueous conditions and at different humidities using neutron and X-ray reflectivity, respectively. X-ray reflectivity measurements complement neutron reflectivity measurements and reveal results that could not be observed by neutron reflectivity measurements. Both methods allow scanning the particle density profile, but due to different contrasts, they are sensitive to different regions within the brush. More specifically, 3-mercaptopropionic acid (MPA)-coated AuNPs were incorporated into poly-[2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) polyelectrolyte brushes at different pH values. The pH value triggers a change in the AuNP surface charge caused by the pH-sensitivity of the MPA ligands, while the charge of the PMETAC brush is not affected by pH variations. The particle number density as well as the particle distribution depend strongly on the pH value of the incubation medium: a rather non-homogeneous assembly (2D assembly) is found when the PMETAC brush is incubated in AuNP suspension at pH 4, while a more homogeneous assembly (3D assembly) is found when the PMETAC brush is incubated in AuNP suspension at pH 8. The main factor dominating the formation of 2D or 3D assembly is assigned to the particle-particle interaction and not to the particle-polymer interaction. No significant relocation of AuNPs within the brush can be found by changing the environmental conditions. The control of particle amount and distribution within the polymer brush has a strong impact on the optical properties of those composite materials, which is crucial for the fabrication of colorimetric sensors.

8.
Sci Rep ; 7(1): 15339, 2017 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-29127413

RESUMEN

We compared the effect of cholesterol at different concentration on the phase behaviour of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) multilamellar vesicles. We used pressure perturbation differential scanning calorimetry (PPC) that studies a system on the whole by giving access to relevant thermodynamic quantities, and elastic incoherent neutron scattering (EINS) that probes local motions of a system at the atomic level by allowing extraction of dynamical parameters. PPC revealed that the volume expansion coefficient of DMPC and DMPC/Cholesterol samples with 13 and 25 mol% cholesterol is a linear function of the heat capacity measured by differential scanning calorimetry. Neutron backscattering spectroscopy showed that the mean square displacements of H atoms do exhibit an increase with temperature and a decrease under increasing pressure. Cholesterol added at concentrations of 25 and 50 mol% led to suppression of the main phase transition. Taking advantage of these results, the present study aims (i) to show that calorimetry and EINS using the Bicout and Zaccai model equally permit to get access to thermodynamic quantities characterizing pure DMPC and DMPC/cholesterol mixtures, thus directly confirming the theoretical method, and (ii) to validate our approach as function of temperature and of pressure, as both are equally important and complementary thermodynamic variables.


Asunto(s)
Colesterol/química , Dimiristoilfosfatidilcolina/química , Membrana Dobles de Lípidos/química , Presión , Termodinámica , Rastreo Diferencial de Calorimetría
9.
Artículo en Inglés | MEDLINE | ID: mdl-28254380

RESUMEN

We determined the activity of glyceroneogenesis from [2-14C]-pyruvate, the phosphoenolpyruvate carboxykinase activity, [2-14C]-pyruvate oxidation and total lipid levels in the hepatopancreas of the crab Neohelice granulata fed with a carbohydrate-rich (HC) diet or a high-protein (HP) diet and then subjected to 5weeks of starvation, in summer and winter, to determine whether the seasonal adjustments of lipid metabolism to food scarcity are modulated by the composition of the diet previously given to the crabs. The results demonstrated that glyceroneogenesis is an active pathway in N. granulata hepatopancreas, and is regulated by seasonal variations, diet composition and starvation. This study showed that in summer the increase in the hepatopancreas glyceroneogenesis activity is among the strategies used by N. granulata fed an HP diet, to maintain the triglyceride/fatty acid cycle during starvation, a normal condition in the biological cycle of this crab. However, the administration of an HC diet reduced the glyceroneogenesis capacity in response to starvation in summer. In winter, the decrease in the glyceroneogenesis capacity in both fed (HP and HC diets) and starved crabs seems to be a strategy to reduce energy consumption and/or requirement. In contrast to the summer results, the incorporation of [2-14C]-pyruvate into 14CO2 was markedly higher in both diet (HC and HP) groups and in starved crabs during the winter. Four decades after the first study describing the glyceroneogenesis pathway in rat white adipose tissue, this pathway is evidenced for the first time in a crustacean.


Asunto(s)
Braquiuros/metabolismo , Dieta , Gluconeogénesis/fisiología , Glucosa/metabolismo , Glicerol/metabolismo , Hepatopáncreas/metabolismo , Inanición , Animales , Carbohidratos de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , Ácidos Grasos/metabolismo , Estaciones del Año
10.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467092

RESUMEN

Abstract The fish may experience periods of food deprivation or starvation which produce metabolic changes. In this study, adult Rhamdia quelen males were subjected to fasting periods of 1, 7, 14, and 21 days and of refeeding 2, 4, 6, and 12 days. The results demonstrated that liver protein was depleted after 1 day of fasting, but recovered after 6 days of refeeding. After 14 days of fasting, mobilization in the lipids of the muscular tissue took place, and these reserves began to re-establish themselves after 4 days of refeeding. Plasmatic triglycerides increased after 1 day of fasting, and decreased following 2 days of refeeding. The glycerol in the plasma oscillated constantly during the different periods of fasting and refeeding. Changes in the metabolism of both protein and lipids during these periods can be considered as survival strategies used by R. quelen. The difference in the metabolic profile of the tissues, the influence of the period of fasting, and the type of reserves mobilized were all in evidence.


Resumo Os peixes podem sofrer períodos de privação de alimentos ou de fome, que produzem mudanças metabólicas. Neste estudo, jundiás machos adultos foram submetidos a jejum períodos de 1, 7, 14 e 21 dias e realimentação 2, 4, 6, e 12 dias. Os resultados demonstraram que a proteína do fígado foi esgotada depois de um dia de jejum, mas restabeleceu após 6 dias de realimentação. Após 14 dias de jejum, ocorreu a mobilização dos lípidos no tecido muscular sendo que estas reservas começaram a re-estabelecer-se após 4 dias de realimentação. Os triglicérides plasmáticos aumentam após um dia de jejum, e diminuiram após 2 dias de realimentação. O glicerol no plasma oscilou constantemente durante os diferentes períodos de jejum e realimentação. As alterações no metabolismo de proteína e lipídios durante estes períodos podem ser consideradas uma estratégias de sobrevivência utilizada pelo Rhamdia quelen. Sendo que a diferença no perfil metabólico tecidual bem como a influência do período de jejum e o tipo de reserva a ser mobilizada foram observadas neste estudo.

11.
Rev Sci Instrum ; 87(10): 105112, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27802707

RESUMEN

We present an upgrade to the time-of-flight neutron reflectometer BioRef at the research reactor BER II of the Helmholtz-Zentrum Berlin für Materialien und Energie (HZB). Through the integration of an additional chopper into the existing setup, the available wavelength resolution is significantly extended. Now two distinct operation modes can be used: a high resolution mode with Δλ/λ ranging from 1% to 5%, which allows for the investigation of thick films up to 4000 Å, and a high flux mode with Δλ/λ = 7%-11%. In the high flux mode, reflectivity curves from 0.007 Å-1 to 0.2 Å-1 with three angular settings can be recorded in 7 min. For a single angular setting and its respective window in Q-space, a time resolution of even less than 4 min is reached. The different configurations are documented by respective measurements (a) on a Ni-Ti multilayer and (b) the swelling kinetics of a solid-supported phospholipid coating upon incubation in a polyelectrolyte solution.


Asunto(s)
Modelos Teóricos , Difracción de Neutrones , Dispersión de Radiación , Difracción de Neutrones/instrumentación , Difracción de Neutrones/métodos
12.
Biochim Biophys Acta ; 1858(9): 2006-2018, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27195429

RESUMEN

To optimize transdermal application of drugs, the barrier function of the skin, especially the stratum corneum (SC), needs to be reduced reversibly. For this purpose, penetration enhancers like urea or taurine are applied. Until now, it is unclear if this penetration enhancement is caused by an interaction with the SC lipid matrix or related to effects within the corneocytes. Therefore, the effects of both hydrophilic enhancers on SC models with different dimensionality, ranging from monolayers to multilayers, have been investigated in this study. Many sophisticated methods were applied to ascertain the mode of action of both substances on a molecular scale. The experiments reveal that there is no specific interaction when 10% urea or 5% taurine solutions are added to the SC model systems. No additional water uptake in the head group region and no decrease of the lipid chain packing density have been observed. Consequently, we suppose that the penetration enhancing effect of both substances might be based on the introduction of large amounts of water into the corneocytes, caused by the enormous water binding capacity of urea and a resulting osmotic pressure in case of taurine.


Asunto(s)
Lípidos de la Membrana/química , Modelos Biológicos , Piel/química , Taurina/química , Urea/química , Administración Cutánea , Humanos , Lípidos de la Membrana/metabolismo , Permeabilidad , Piel/metabolismo , Taurina/farmacocinética , Urea/farmacocinética
13.
Phys Chem Chem Phys ; 17(5): 3157-63, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25515378

RESUMEN

We used small-angle neutron scattering (SANS) to study the effects of high hydrostatic pressure on the structure of human acetylcholinesterase (hAChE). At atmospheric pressure, our SANS results obtained on D11 at ILL (Grenoble, France) give a radius of gyration close to that calculated for a mixture of monomers, dimers and tetramers of the enzyme, suggesting a good agreement between hAChE crystal structure and its conformation in solution. Applying high pressure to the sample we found a global compression of about 11% of the enzyme up to a pressure of 900 bar and then again an extension up to 2.1 kbar indicating unfolding of the tertiary structure due to a molten globule (MG) state. On the other hand, we studied the influence of pressure up to 6 kbar on the dynamics of this enzyme, on the backscattering spectrometer IN13 at ILL. For the first time, we used elastic incoherent neutron scattering (EINS) to probe the differences between hAChE in its folded state (N), its high-pressure induced MG state and its unfolded state (U). Especially around the MG state at 1750 bar we found a significant increase in the dynamics, indicating a partial unfolding. A four-step-model is suggested to describe the changes in the protein.


Asunto(s)
Acetilcolinesterasa/química , Difracción de Neutrones , Dispersión del Ángulo Pequeño , Acetilcolinesterasa/genética , Acetilcolinesterasa/metabolismo , Humanos , Presión , Estructura Terciaria de Proteína , Desplegamiento Proteico , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
14.
J R Soc Interface ; 11(97): 20140372, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-24872501

RESUMEN

It is a long debated question whether catalytic activities of enzymes, which lie on the millisecond timescale, are possibly already reflected in variations in atomic thermal fluctuations on the pico- to nanosecond timescale. To shed light on this puzzle, the enzyme human acetylcholinesterase in its wild-type form and complexed with the inhibitor huperzine A were investigated by various neutron scattering techniques and molecular dynamics simulations. Previous results on elastic neutron scattering at various timescales and simulations suggest that dynamical processes are not affected on average by the presence of the ligand within the considered time ranges between 10 ps and 1 ns. In the work presented here, the focus was laid on quasi-elastic (QENS) and inelastic neutron scattering (INS). These techniques give access to different kinds of individual diffusive motions and to the density of states of collective motions at the sub-picoseconds timescale. Hence, they permit going beyond the first approach of looking at mean square displacements. For both samples, the autocorrelation function was well described by a stretched-exponential function indicating a linkage between the timescales of fast and slow functional relaxation dynamics. The findings of the QENS and INS investigation are discussed in relation to the results of our earlier elastic incoherent neutron scattering and molecular dynamics simulations.


Asunto(s)
Acetilcolinesterasa/química , Alcaloides/química , Inhibidores de la Colinesterasa/química , Modelos Químicos , Simulación de Dinámica Molecular , Sesquiterpenos/química , Sitios de Unión , Catálisis , Activación Enzimática , Humanos , Cinética , Unión Proteica , Estadística como Asunto
15.
Eur J Surg Oncol ; 36(8): 783-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20510570

RESUMEN

AIM: Metastases can occur in up to 15% of all melanoma patients with negative sentinel lymph node examination (SN -). We retrospectively investigated the number of preoperatively marked sentinel lymph nodes (SNs) with lymphoscintigraphy and effectively surgically removed SNs in SN--patients with cutaneous melanoma >or=0.5 mm. Ratio of these parameters was calculated and impact of this ratio as well as impact of scintigraphic appearance time (SAT) on disease progression was studied. MATERIALS AND METHODS: Data on 122 SN--patients--70 women (58%), mean age 56.5 years--were analyzed. Mean follow-up time was 58 months. RESULTS: Mean tumour thickness of all patients was 2.3 mm. In 51 patients (42%) the number of SNs marked in lymphoscintigraphy was higher than excised in surgery, in 47 patients (38%) the same number as marked was excised and in 24 patients (20%) a lower number was marked than excised. Metastases occurred in 17 patients (14%) after a mean time of 24.8 months. Mean tumour thickness (5.4 mm) was significantly higher in these patients than in the other patients (p = 0.000). Ratio of marked and excised SNs had no influence on disease progression; the only parameter influencing outcome was tumour thickness (p = 0.000). Short SAT was significantly associated with higher tumour thickness (p = 0.004). CONCLUSION: Our study indicates that, in routine clinical practice, it suffices to harvest the first SN, as the ratio of marked and excised SNs has no impact on disease progression.


Asunto(s)
Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/cirugía , Melanoma/diagnóstico por imagen , Melanoma/cirugía , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Masculino , Melanoma/patología , Persona de Mediana Edad , Cintigrafía , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias Cutáneas/patología , Adulto Joven
16.
J Eur Acad Dermatol Venereol ; 21 Suppl 2: 14-8, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17716287

RESUMEN

Emollients play an important part in the management of patients with dry skin disorders, such as atopy, allergy, eczema, psoriasis or dryness following chemotherapy or radiotherapy. Their use in the treatment of diseased and sensitive skin requires not only an efficient hydrating and lipid-replenishing effect on the skin, but minimal risk for skin irritation or sensitization. This will be influenced by their formulation and number and type of ingredients and, due to the nature of their application, requires clinical testing to ensure their appropriateness for dermatological rather than cosmetic use. A new generation of emollients has been developed for the care of dry, or very dry, and sensitive skin. Among these, Dardia Lipo Line (Intendis GmbH, Berlin, Germany) has been formulated specifically for use in post-therapy preventive skin care. The current clinical evidence for this line of emollients is reviewed here.


Asunto(s)
Emolientes/efectos adversos , Emolientes/uso terapéutico , Enfermedades de la Piel/tratamiento farmacológico , Emulsiones , Humanos , Pomadas
17.
Eur J Appl Physiol ; 101(4): 495-502, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17674028

RESUMEN

The therapeutic application of pulsed electromagnetic fields (PEMFs) can accelerate healing after bone fractures and also alleviate pain according to several studies. However, no objective criteria have been available to ensure appropriate magnetic field strength or type of electromagnetic field. Moreover, few studies so far have investigated the physical principles responsible for the impact of electromagnetic fields on the human body. Existing studies have shown that PEMFs influence cell activity, the autonomic nervous system and the blood flow. The aim of this study is to examine the instantaneous and short-term effects of a PEMF therapy and to measure the impact of different electromagnetic field strengths on a range of physiological parameters, especially the autonomic nervous systems, determined by heart rate variability (HRV) as well as their influence on subjects' general feeling of well-being. The study comprised experimental, double-blind laboratory tests during which 32 healthy male adults (age: 38.4+/-6.5 years) underwent four physical stress tests at standardised times followed by exposure to pulsed magnetic fields of varying intensity [HPM, High Performance magnetic field; Leotec; pulsed signal; mean intensity increase: zero (placebo), 0.005, 0.03 and 0.09 T/s]. Exposure to electromagnetic fields after standardised physical effort significantly affected the very low frequency power spectral components of HRV (VLF; an indicator for sympathetically controlled blood flow rhythms). Compared to placebo treatment, exposure to 0.005 T/s resulted in accelerated recovery after physical strain. Subjects with lower baseline VLF power recovered more quickly than subjects with higher VLF when exposed to higher magnetic field strengths. The application of electromagnetic fields had no effect on subjects' general feeling of well-being. Once the magnetic field exposure was stopped, the described effects quickly subsided. PEMF exposure has a short-term dosage-dependent impact on healthy subjects. Exposure to PEMF for 20 min resulted in more rapid recovery of heart rate variability, especially in the very low frequency range after physical strain. The study also showed the moderating influence of the subjects' constitutional VLF power on their response to PEMF treatment. These findings have since been replicated in a clinical study and should be taken into consideration when PEMF treatment is chosen.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Sistema Nervioso Autónomo/efectos de la radiación , Campos Electromagnéticos , Ejercicio Físico/fisiología , Adulto , Algoritmos , Actitud , Relación Dosis-Respuesta en la Radiación , Método Doble Ciego , Ejercicio Físico/psicología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Psicometría
19.
Rofo ; 172(1): 43-50, 2000 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-10719462

RESUMEN

PURPOSE: An evaluation of clinical and computed tomography parameters for the transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: Retro- and prospective analysis of 123 TACE procedures in 37 patients (mean age: 63.3 years). RESULTS: Overall mean survival rate for all treated patients was 785 days with a mean value of 387 days. The 1 year survival rate was 62%. Quantitative tumor volumetry revealed a significant difference in survival rate with a mean value of 678 days for patients with a reduction of tumor volume between 0 and 50%, 976 days for a volume reduction of 51-100% and 277 days for an increase in tumor volume during therapy. Patients with a high lipiodol retention presented improved survival data (902 days) versus patients with a low lipiodol retention (513 days). Homogeneous retention of lipiodol was a positive factor on survival as compared to an inhomogenous form of retention. CONCLUSION: In patients with a positive therapy response after TACE the prognosis can be improved by repeated embolization.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Tomografía Computarizada por Rayos X , Anciano , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/mortalidad , Cisplatino/administración & dosificación , Terapia Combinada , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intraarteriales , Aceite Yodado/administración & dosificación , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/irrigación sanguínea , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/terapia , Tasa de Supervivencia , Resultado del Tratamiento
20.
Radiology ; 214(2): 349-57, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10671580

RESUMEN

PURPOSE: To evaluate the prognostic value of volumetric computed tomography (CT) for therapy control in patients treated with repeated transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Eighty-five patients with histologically proved HCC underwent 182 TACE procedures with 50 mg/m(2) doxorubicin hydrochloride, 50 mg/m(2) cisplatin, 10 mL/m(2) iodized oil, and amilomer microspheres. The volumes of liver and tumor were measured with a region-of-interest CT technique. Iodized oil retention was estimated with CT performed 24-48 hours after treatment. RESULTS: Tumor volume expressed as a percentage of liver volume was less than 5% in 26, less than 15% in 33, and 15% or greater in 26 patients. The overall 1-year survival rate was 57.6% (mean, 534 days; median, 428 days). There was a statistically significant prolongation of survival when the tumor volume was less than 200 mL (P <.02) and less than 5% of the liver volume (P <.01). Complete (>/=75%) and good (50%-74%) iodized oil retention raised the median survival significantly (P <.001 and P <.07, respectively). Significantly reduced survival correlated with diffuse tumor growth pattern (P <.05) and presence of more than nine lesions (P <.03). CONCLUSION: TACE resulted in significant prolongation of survival in patients with tumor volumes of less than 200 mL, tumor-to-liver volume ratios of less than 5%, and iodized oil retention greater than or equal to 75%.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Cisplatino/administración & dosificación , Medios de Contraste , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intraarteriales , Aceite Yodado/administración & dosificación , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Trasplante de Hígado , Masculino , Microesferas , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento
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