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1.
Sci Rep ; 14(1): 10542, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719895

RESUMO

We experimentally demonstrate resonance of first-order vector vortex beams (VVB) with a triangular optical cavity. We also show that, due to their symmetry properties, the VVBs commonly known as radial and azimuthal beams do not resonate at the same cavity length, which could be explored to use the triangular resonator as a mode sorter. In addition, an intracavity Pancharatnam phase shifter (PPS) is implemented in order to compensate for any birefringent phase that the cavity mirrors may introduce.

3.
Braz J Med Biol Res ; 52(2): e7773, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30698227

RESUMO

The aim of this study was to evaluate the therapeutic effects of ultrasound (US)-mediated phonophoresis alone or in association with diclofenac diethylammonium (DCF) administered topically in animal models of inflammation. A pre-clinical, prospective, and randomized experimental study of quantitative and qualitative nature was carried out. Phonophoresis was performed using a therapeutic ultrasound apparatus in two distinct models of acute inflammation. Edema was induced by an intraplantar injection of carrageenan and measured by plethysmography. The Hargreaves test was used to evaluate the antinociceptive activity and investigate the action of phonophoresis on tumor necrosis factor (TNF)-α production. A histological analysis with hematoxylin-eosin was used to evaluate tissue repair, and the expression of COX-2 was determined by immunohistochemical analysis. At the peak of inflammatory activity (3 h), treatment with US, US+DCF, and DCF significantly reduced edema formation compared to the control group. Treatment with US+DCF was more effective than treatment with US alone at both analyzed times. In the analysis of the antinociceptive activity, the treatments significantly increased the latency time in response to the thermal stimulus. Histopathological analysis revealed a reduction of the inflammatory infiltrates and immunohistochemistry demonstrated that the association was effective in reducing COX-2 expression compared to the control group. The association of DCF with US produced anti-inflammatory and antinociceptive effects in rat models of inflammation, which may be associated with inhibition of COX-2 and TNF-α production.


Assuntos
Analgésicos/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Diclofenaco/administração & dosagem , Inflamação/tratamento farmacológico , Fonoforese , Terapia por Ultrassom/métodos , Administração Tópica , Animais , Modelos Animais de Doenças , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Estudos Prospectivos , Distribuição Aleatória , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa
4.
Braz. j. med. biol. res ; 52(2): e7773, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-984030

RESUMO

The aim of this study was to evaluate the therapeutic effects of ultrasound (US)-mediated phonophoresis alone or in association with diclofenac diethylammonium (DCF) administered topically in animal models of inflammation. A pre-clinical, prospective, and randomized experimental study of quantitative and qualitative nature was carried out. Phonophoresis was performed using a therapeutic ultrasound apparatus in two distinct models of acute inflammation. Edema was induced by an intraplantar injection of carrageenan and measured by plethysmography. The Hargreaves test was used to evaluate the antinociceptive activity and investigate the action of phonophoresis on tumor necrosis factor (TNF)-α production. A histological analysis with hematoxylin-eosin was used to evaluate tissue repair, and the expression of COX-2 was determined by immunohistochemical analysis. At the peak of inflammatory activity (3 h), treatment with US, US+DCF, and DCF significantly reduced edema formation compared to the control group. Treatment with US+DCF was more effective than treatment with US alone at both analyzed times. In the analysis of the antinociceptive activity, the treatments significantly increased the latency time in response to the thermal stimulus. Histopathological analysis revealed a reduction of the inflammatory infiltrates and immunohistochemistry demonstrated that the association was effective in reducing COX-2 expression compared to the control group. The association of DCF with US produced anti-inflammatory and antinociceptive effects in rat models of inflammation, which may be associated with inhibition of COX-2 and TNF-α production.


Assuntos
Animais , Masculino , Ratos , Fonoforese , Anti-Inflamatórios não Esteroides/administração & dosagem , Diclofenaco/administração & dosagem , Analgésicos/administração & dosagem , Inflamação/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Terapia por Ultrassom/métodos , Distribuição Aleatória , Estudos Prospectivos , Administração Tópica , Fator de Necrose Tumoral alfa , Ratos Wistar , Modelos Animais de Doenças , Inflamação/fisiopatologia , Inflamação/patologia
5.
Animal ; 12(s2): s282-s294, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30139403

RESUMO

The present review will present the recent published results and discuss the main effects of nutrients, mainly fatty acids, on the expression of genes involved in lipid metabolism. In this sense, the review focuses in two phases: prenatal life and finishing phase, showing how nutrients can modulate gene expression affecting marbling and fatty acid profile in meat from ruminants. Adiposity in ruminants starts to be affected by nutrients during prenatal life when maternal nutrition affects the differentiation and proliferation of adipose cells enhancing the marbling potential. Therefore, several fetal programming studies were carried out in the last two decades in order to better understand how nutrients affect long-term expression of genes involved in adipogenesis and lipogenesis. In addition, during the finishing phase, marbling becomes largely dependent on starch digestion and glucose metabolism, being important to create alternatives to increase these metabolic processes, and modulates gene expression. Different lipid sources and their fatty acids may also influence the expression of genes responsible to encode enzymes involved in fat tissue deposition, influencing meat quality. In conclusion, the knowledge shows that gene expression is a metabolic factor affecting marbling and fatty acid profile in ruminant meat and diets and their nutrients have direct effect on how these genes are expressed.


Assuntos
Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Carne/análise , Nutrigenômica , Ruminantes/metabolismo , Adipócitos/metabolismo , Adiposidade , Animais , Dieta/veterinária , Lipogênese , Amido/metabolismo
6.
Skin Res Technol ; 23(3): 429-436, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27882608

RESUMO

BACKGROUND/PURPOSE: Human skin anisotropy is difficult to quantify. The Cutiscan® , is allegedly, the first biometrical system to provide information on the elastic and viscoelastic properties, as well as on anisotropy and directionality of the human skin in vivo. Thus, this study aims to contribute to characterize this new device and its applicability, and to compare its behavior with two other well-known devices-the Cutometer® and the Reviscometer® . METHODS: Measurements were conducted with each device in three different anatomical sites (forehead, forearm and leg) of 20 female volunteers engaged after informed consent. The participants in the study were aged 19-73 years (mean age 37 ± 18.7 years old), and were divided in two groups (n = 10), based on their age - Group I, mean age 22 ± 1.3 years; Group II, mean age 52 ± 13.7 years. RESULTS: All devices were useful tools to explore the anatomical and the age dependant changes in biomechanical terms, showing different discriminative capacities. Interesting correlations were established between the variables provided by the equipment. CONCLUSION: The Cutiscan® descriptors delivered excellent relationships with those from Cutometer® and Reviscometer® , while providing more detailed information about skin anisotropy through a full 360° analysis.


Assuntos
Anisotropia , Dermatologia/instrumentação , Elasticidade/fisiologia , Pele/anatomia & histologia , Adulto , Idoso , Fenômenos Biomecânicos/fisiologia , Biometria/instrumentação , Desenho de Equipamento/estatística & dados numéricos , Feminino , Antebraço/anatomia & histologia , Antebraço/patologia , Testa/anatomia & histologia , Testa/patologia , Humanos , Pessoa de Meia-Idade , Pele/patologia , Envelhecimento da Pele/fisiologia , Fenômenos Fisiológicos da Pele
7.
Genet Mol Res ; 15(4)2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27819725

RESUMO

The etiology of adolescent idiopathic scoliosis remains unknown. Angiotensin-converting enzyme and α-actinin-3 polymorphisms influence the characteristics of muscle fibers. The aim of this study was to examine the association between idiopathic scoliosis and genetic polymorphism of angiotensin-converting enzyme and α-actinin-3. Ninety-seven females with scoliosis, and 137 healthy, age-matched control females were studied. The presence of polymorphisms was determined by PCR. A χ2 test was used to analyze differences, and odds ratios were estimated. The frequencies of ACE genotypes in the scoliotic group were 46.4% DD, 45.4% ID, and 8.2% II, while in the control group they were 40.1% DD, 43.8% ID, and 16.1% II (P = 0.197). The D allele had a frequency of 69.1% in patients with idiopathic scoliosis and 62% in the control group (P = 0.116). The frequencies of ACTN3 genotypes in females with scoliosis were 31.8% RR, 49.4% RX, and 18.8% XX, while in the control group they were 35% RR, 49% RX, and 16% XX (P = 0.810). The frequency of the R allele was 56.4% in the scoliotic group and 59.6% in the control group (P = 0.518). There was no statistically significant association between angiotensin-converting enzyme or α-actinin-3 polymorphisms and the presence of adolescent idiopathic scoliosis in females.


Assuntos
Actinina/genética , Predisposição Genética para Doença , Mutação INDEL/genética , Peptidil Dipeptidase A/genética , Polimorfismo de Nucleotídeo Único/genética , Escoliose/genética , Adolescente , Adulto , Feminino , Técnicas de Genotipagem , Humanos , Razão de Chances , Adulto Jovem
8.
Skin Res Technol ; 21(4): 413-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26058417

RESUMO

BACKGROUND/PURPOSE: The importance of water in human physiology is well known, also for skin functionality. This study was conducted to assess the effects of dietary water on epidermal skin hydration in healthy females. METHODS: Thirty-four healthy females (mean 24.5 ± 6.34 years old) were selected and characterized according to their dietary daily habits, by a previously validated Food Frequency Questionnaire. For 1 month, these subjects were asked to add 2 L/day of water to their regular dietary habits. Measurements took place at day D0, D15, and D30, and involved general variables (body weight, blood pressure, Body Mass Index) and specific skin physiological variables in five anatomical sites (ventral forearm, anterior leg, dorsal hand, zygomatic area, and forehead) involving epidermal superficial and deep hydration, by capacitance and transepidermal water loss (TEWL). RESULTS: This water overload (2 L/day/30 days) did not change the blood volume or weight of the individuals. However, both superficial and deep skin hydration were clearly in those individuals that regularly consumed lees water per day. No significant effect was observed in the TEWL. CONCLUSIONS: This study clearly suggests that dietary water intake seems to influence skin water content. Nevertheless further in vivo investigations involving other variables, such as biomechanical descriptors, should follow to look deeper into this aspect of skin physiology.


Assuntos
Água Corporal/fisiologia , Ingestão de Líquidos/fisiologia , Epiderme/fisiologia , Perda Insensível de Água/fisiologia , Água/administração & dosagem , Água/metabolismo , Administração Oral , Água Corporal/efeitos dos fármacos , Feminino , Humanos , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Perda Insensível de Água/efeitos dos fármacos , Adulto Jovem
9.
Int J Cosmet Sci ; 37(5): 506-10, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25819329

RESUMO

OBJECTIVE: Green coffee oil (GCO) has been used in cosmetic formulations due to its emollient and anti-ageing properties. However, there are insufficient studies about its safety when applied in cosmetic formulations. METHODS: Cytotoxicity of GCO and of formulations containing 2.5-15% of GCO was evaluated by the MTT reduction assay, in human keratinocytes. Formulations containing 15% of GCO and the vehicle were applied under in use conditions in the volar forearm of human volunteers during 3 days. Transepidermal water loss, stratum corneum water content and erythema index were evaluated each 24 h using biophysical techniques. The same formulations were probed for skin tolerance through a patch test. RESULTS: Neither pure GCO nor its formulations showed cytotoxic effects in concentrations up to 100 µg mL(-1) . Transepidermal water loss values showed a slight reduction when the formulation containing GCO was applied. Stratum corneum water content and erythema index did not show significant differences, as the results observed in the first day of the study were maintained throughout 3 days. None of the volunteers display any reaction after using an occlusive patch. CONCLUSION: The results obtained in the study indicate that GCO seems to be safe for topical applications and showed good skin compatibility under the experimental conditions of the study.


Assuntos
Café , Cosméticos , Óleos de Plantas , Pele , Células Cultivadas , Humanos
10.
ACS Appl Mater Interfaces ; 1(10): 2353-62, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20355873

RESUMO

Zn-Al and Mg-Al layered double hydroxides (LDHs) loaded with quinaldate and 2-mercaptobenzothiazolate anions were synthesized via anion-exchange reaction. The resulting compounds were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy/energy-dispersive X-ray spectroscopy. Spectrophotometric measurements demonstrated that the release of organic anions from these LDHs into the bulk solution is triggered by the presence of chloride anions, evidencing the anion-exchange nature of this process. The anticorrosion capabilities of LDHs loaded with organic inhibitors toward the AA2024 aluminum alloy were analyzed by electrochemical impedance spectroscopy. A significant reduction of the corrosion rate is observed when the LDH nanopigments are present in the corrosive media. The mechanism by which the inhibiting anions can be released from the LDHs underlines the versatility of these environmentally friendly structures and their potential application as nanocontainers in self-healing coatings.

11.
Med Biol Eng Comput ; 43(6): 771-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16594305

RESUMO

Understanding the human cutaneous barrier function is one of the main goals in the study of skin physiology. The plastic occlusion stress test (POST) is a well-known, dynamic approach for studying the barrier, evoking an over-stimulation of the cutaneous water assessed by the trans-epidermal water loss (TEWL) measurement. Rigorous data analysis is imperative, and the compartmental model proposed is particularly suitable for this purpose. It provides a dynamic quantitative description of water mass, but also helps to disclose the relative influence of other factors, such as the time of occlusion. Ten healthy volunteers were submitted to POST studies with different occlusion periods (1 h, 6 h, 12 h and 24 h), allowing the full application of the model to the measured desorption curves. After fitting, the influence of the occlusion time over the evaporation half-lives (t1/2evap) is apparent (t1/2evap ranging from 2.46 min for 1 h of occlusion to 8.53 min for 24 h), increasing with time. Considering the wide applicability of the POST to the study of in vivo cutaneous physiology and pathophysiology, these results demonstrate that the time of occlusion must be considered as a key factor in POST measurements.


Assuntos
Modelos Biológicos , Fenômenos Fisiológicos da Pele , Perda Insensível de Água/fisiologia , Adulto , Feminino , Humanos , Masculino , Curativos Oclusivos , Fatores de Tempo
12.
Int J Cosmet Sci ; 27(4): 237-41, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18492192

RESUMO

The measurement of transepidermal water loss (TEWL) has been established as one of the main parameters in the assessment of skin barrier function. One of the most widely employed devices to measure TEWL is the Tewameter. Courage and Khazaka launched the TM300 in 2003 and successfully eliminated some of the limitations of the previous model. In the more recent device, the sensors inside the probe head can be pre-heated to a temperature close to that of the skin, which considerably decreases sampling time. Additionally, the new technology of the probe does not require frequent and time-consuming recalibration with different solutions. The main objective of this work was to perform a comparative assessment of the performance of the two different Tewameter models. Fifteen volunteers were used in this study, which was conducted in the mid-portion of the volar forearm. The standard measurements assessed differences in the basal values, time necessary for a stable value and coefficient of variability under normal and extreme conditions. The dynamic measurements performed were based on a plastic occlusion stress test (POST), involving the application of an occlusive patch for 24 h, after which the TEWL desorption curves were recorded. A mathematical model was adjusted to the data points using a specially modified simplex routine. Calculated parameters considered relevant to the study were t(1/2evap) (evaporation half-life) and dynamic water mass (DWM). Results show slight differences in the performance the two models, which are nevertheless statistically significant. The TM300 seems to be more sensitive to differences in TEWL and presents a much quicker measurement capacity. These results confirm a marked improvement in the more recent Tewameter model, when compared with its predecessor. The main conclusion of this work is that caution is advised when comparing results obtained with the two different models and that studies should be carried out entirely with the same device.

13.
Cancer Chemother Pharmacol ; 55(2): 117-28, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15592719

RESUMO

PURPOSE: We have shown previously that carbogen (95% 0(2), 5% CO(2)) breathing by rodents can increase uptake of anticancer drugs into tumours. The aim of this study was to extend these observations to other rodent models using the anticancer drug 5-fluorouracil (5FU). 5FU pharmacokinetics in tumour and plasma and physiological effects on the tumour by carbogen were investigated to determine the locus of carbogen action on augmenting tumour uptake of 5FU. METHODS: Two different tumour models were used, rat GH3 prolactinomas xenografted s.c. into nude mice and rat H9618a hepatomas grown s.c. in syngeneic Buffalo rats. Uptake and metabolism of 5FU in both tumour models with or without host carbogen breathing was studied non-invasively using fluorine-19 magnetic resonance spectroscopy ((19)F-MRS), while plasma samples from Buffalo rats were used to construct a NONMEM pharmacokinetic model. Physiological effects of carbogen on tumours were studied using (31)P-MRS for energy status (NTP/Pi) and pH, and gradient-recalled echo magnetic resonance imaging (GRE-MRI) for blood flow and oxygenation. RESULTS: In both tumour models, carbogan-induced GRE-MRI signal intensity increases of approximately 60% consistent with an increase in tumour blood oxygenation and/or flow. In GH3 xenografts, (19)F-MRS showed that carbogen had no significant effect on 5FU uptake and metabolism by the tumours, and (31)P-MRS showed there was no change in the NTP/Pi ratio. In H9618a hepatomas, (19)F-MRS showed that carbogen had no effect on tumour 5FU uptake but significantly ( p=0.0003) increased 5FU elimination from the tumour (i.e. decreased the t(1/2)) and significantly ( p=0.029) increased (53%) the rate of metabolism to cytotoxic fluoronucleotides (FNuct). The pharmacokinetic analysis showed that carbogen increased the rate of tumour uptake of 5FU from the plasma but also increased the rate of removal. (31)P-MRS showed there were significant ( p

Assuntos
Dióxido de Carbono/farmacologia , Fluoruracila/farmacocinética , Oxigênio/farmacologia , Animais , Dióxido de Carbono/administração & dosagem , Neoplasias Hepáticas Experimentais/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Modelos Biológicos , Transplante de Neoplasias , Oxigênio/administração & dosagem , Prolactinoma/metabolismo , Ratos , Transplante Heterólogo
14.
MAGMA ; 17(3-6): 260-70, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15703983

RESUMO

To characterize spontaneously occurring c-neu/HER2 overexpressing tumours in oncomice and their response to herceptin by non-invasive magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI). Oncomice were monitored by localized 31P MRS during unperturbed growth and before and after treatment with 10 mg/kg herceptin (Hoffman La Roche) intraperitoneally for up to 21 days post-treatment. Vascular morphology and function was assessed by quantitation of tumour magnetic resonance (MR) relaxation rates R2* and R2 prior to and either during carbogen (95% O2/5% CO2) breathing or following administration of the blood-pool contrast agent NC100150 (Clariscan, Amersham Health). Immunohistochemistry showed strong membrane staining for HER2 protein overexpression. The 31P MRS showed only a significant (p<0.01) increase of phosphomonoester / total phosphate ratio over 21 days of growth. Herceptin increased the tumour volume doubling time compared to untreated tumours and significantly increased the phosphomonoester / beta-nucleoside triphosphate ratio 2 days after treatment (p=0.01). Tumours showed a highly heterogeneous yet significant (p<0.01) decrease or increase in R2* in response to carbogen or NC100150 respectively. The absence of a decline in tumour bioenergetics with growth, commonly seen in 31P MRS studies of transplanted rodent tumour models, coupled with the heterogeneous blood volume revealed by 1H MRI, suggest a metabolic and vascular phenotype similar to that found in human tumours.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Interpretação de Imagem Assistida por Computador/métodos , Espectroscopia de Ressonância Magnética/métodos , Neoplasias Mamárias Experimentais/diagnóstico , Neoplasias Mamárias Experimentais/tratamento farmacológico , Animais , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Humanos , Neoplasias Mamárias Experimentais/classificação , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Oncogênicas v-erbB/genética , Proteínas Oncogênicas v-erbB/metabolismo , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Trastuzumab , Resultado do Tratamento
15.
Acta Med Port ; 17(1): 59-66, 2004.
Artigo em Português | MEDLINE | ID: mdl-15636729

RESUMO

The cross-cultural translation from spanish to portuguese (european) of the Second Consensus of Granada on Pharmacotherapy failure has the objective to provide clinicians and researchers, working in drug therapy follow-up, with a working tool translated with the accuracy and the reliability that a biomedical document requires. The common origin of the spanish and portuguese languages emphasizes the need to do a cross-cultural translation. Errors of translation or wrong interpretations can be due to falses cognates. The cross-cultural translation followed three steps: translation, back-translation and review of the translation of the original text of the Second Consensus of Granada on Pharmacotherapy failure. The result was the portuguese version of the Second Consensus of Granada on Pharmacotherapy failure, presented in the annex I.


Assuntos
Conferências de Consenso como Assunto , Tratamento Farmacológico , Características Culturais , Idioma , Portugal , Espanha , Falha de Tratamento
16.
Photochem Photobiol ; 77(2): 121-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12785049

RESUMO

Two methylated thienocarbazoles and two of their synthetic nitro-precursors have been examined by absorption, luminescence, laser flash photolysis and photoacoustic techniques. Their spectroscopic and photophysical characterization involves fluorescence spectra, fluorescence quantum yields and lifetimes, and phosphorescence spectra and phosphorescence lifetimes for all the compounds. Triplet-singlet difference absorption spectra, triplet molar absorption coefficients, triplet lifetimes, intersystem crossing S1 --> T1 and singlet molecular oxygen yields were obtained for the thienocarbazoles. In the case of the thienocarbazoles it was found that the lowest-lying singlet and triplet excited states, S1 and T1, are of pi,pi* origin, whereas for their precursors S1 is n,pi*, and T1 is pi,pi*. In both thienocarbazoles it appears that the thianaphthene ring dictates the S1 --> T1 yield, albeit there is less predominance of that ring in the triplet state of the linear thienocarbazole, which leads to a decrease in the observed phiT value.

17.
Int J Cosmet Sci ; 25(1-2): 37-44, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18494881

RESUMO

BACKGROUND: Several methods have been developed to study in vivo the stratum corneum with minimal 'invasion'. Cyanoacrylate adhesives employed in skin surface biopsy (SSB) and tape stripping are commonly used techniques that can be applied to study the different layers of the epidermis or even to permeation studies. However, depending on the type of adhesive tape used and pressure applied, different information is gathered. AIM: The purpose of this study was to identify and compare the impact of both techniques in the normal skin physiology to further establish its potential usefulness and limitations. METHODS: Alterations were focused on basic structural related properties, such as epidermal barrier function (assessed by transepidermal water loss evaporimetry) and flow related changes (by laser Doppler velocimetry and colourimetry). RESULTS/CONCLUSIONS: Results indicate a more pronounced impact of SSB than that of tape stripping, attributable to the removal of a thicker layer of cells. The intertechnique correlation coefficients were good between transepidermal water loss and colourimetry, but poorer between these techniques and laser doppler flowmetry, which probably reflects the difficulties associated with this technique.

18.
BMC Dermatol ; 1: 4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11580871

RESUMO

BACKGROUND: The identification of potential sources of error is a crucial step for any new assessment technique. This is the case for transcutaneous variables, such as flow and arterial gases, which have been applied as functional indicators of various aspects of human health. Regarding gender, a particular subject-related determinant, it is often claimed that women present higher transcutaneous oxygen pressure (tcpO2) values than men. However, the statistical significance of this finding is still uncertain. METHODS: The haemodynamical-vascular response to a local reactive hyperaemia procedure (the tourniquet cuff manoeuvre) was studied in two previously selected group of volunteers (n = 16; 8 women and 8 men). The effect of gender was assessed under standardised experimental conditions, using the transcutaneous flow-related variables tcpO2-tcpCO2 and Laser-doppler Flowmetry (LDF). RESULTS: Regarding tcpO2, statistically significant differences between genders were not found, although higher values were consistently found for the gases in the female group. Regarding LDF, high statistically significant differences (p < 0.005) were found, with the men's group presenting the highest values and variability. Other derived parameters used to characterise the vascular response following the cuff-deflation (t-peak) were similar in both groups. CONCLUSIONS: The relative influence of gender was not clearly demonstrated using these experimental conditions. However the gender-related LDF differences suggest that further investigation should be done on this issue. Perhaps in the presence of certain pathological disparities involving peripheral vascular regulation, other relationships may be found between these variables.


Assuntos
Hemorreologia/normas , Hiperemia/fisiopatologia , Pele/irrigação sanguínea , Adaptação Fisiológica , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Monitorização Transcutânea dos Gases Sanguíneos/normas , Feminino , Hemorreologia/métodos , Humanos , Hiperemia/diagnóstico , Fluxometria por Laser-Doppler/métodos , Masculino , Microcirculação/fisiologia , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Fatores Sexuais
19.
Acta Oncol ; 40(5): 609-14, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11669333

RESUMO

Non-invasive magnetic resonance spectroscopy (MRS) can be used in the clinic to monitor the pharmacokinetics of the chemotherapeutic drug 5-fluorouracil (5-FU) and the effects of modifiers. We report two studies of 5-FU toxicity in normal tissue--one with patients and the other an animal study. 1) 19F MRS signals from fluoronucleotides, cytotoxic anabolites of 5-FU metabolism, were observed in the livers of two patients treated with 5-FU for colorectal cancer, shown by computed tomography (CT) and ultrasound (US) to have no liver metastases. This is the first report of non-invasive monitoring of toxic 5-FU metabolites in normal human tissues. 2) In animals, carbogen-breathing enhances tumour uptake and the efficacy of 5-FU, and the method is under trial in patients. This study demonstrates that there were no significant effects of carbogen breathing on the levels of 5-FU and its metabolites in normal rat tissues, or on the histology of the tissues assessed after treatment.


Assuntos
Dióxido de Carbono/farmacologia , Radioisótopos de Flúor/farmacocinética , Fluoruracila/efeitos adversos , Oxigênio/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Animais , Antimetabólitos Antineoplásicos/uso terapêutico , Disponibilidade Biológica , Medula Óssea/química , Medula Óssea/ultraestrutura , Carcinoma de Células de Transição , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/cirurgia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Terapia Combinada , Evolução Fatal , Feminino , Fluordesoxiuridilato/análise , Fluoruracila/farmacocinética , Fluoruracila/toxicidade , Humanos , Intestino Delgado/química , Intestino Delgado/ultraestrutura , Leucovorina/uso terapêutico , Fígado/química , Fígado/diagnóstico por imagem , Fígado/ultraestrutura , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas , Ratos , Ratos Endogâmicos WF , Neoplasias do Colo Sigmoide/tratamento farmacológico , Neoplasias do Colo Sigmoide/radioterapia , Neoplasias do Colo Sigmoide/cirurgia , Tomografia Computadorizada por Raios X , Ultrassonografia , Neoplasias da Bexiga Urinária
20.
Magn Reson Med ; 46(3): 586-91, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11550253

RESUMO

The first in vivo hyperpolarized 129Xe NMR study in experimental tumors is presented. Hyperpolarized 129Xe was dissolved in solutions, and was injected intratumorally in GH-3 prolactinomas in rats and RIF-1 fibrosarcomas in mice. The 129Xe NMR spectra and apparent spin-lattice relaxation times in the two tumor types present characteristic differences. These differences are discussed in terms of xenon exchange between the carrier medium and the tissue compartments.


Assuntos
Meios de Contraste/farmacocinética , Fibrossarcoma/diagnóstico , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Espectroscopia de Ressonância Magnética , Prolactinoma/diagnóstico , Isótopos de Xenônio/farmacocinética , Animais , Feminino , Fibrossarcoma/patologia , Humanos , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Prolactinoma/patologia , Ratos , Ratos Endogâmicos WF , Células Tumorais Cultivadas/patologia
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