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1.
J Photochem Photobiol B ; 165: 1-9, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27755994

RESUMO

In the present study, SiO2 nanoparticles functionalized with 3-(2-aminoethylamino)propyl group (SiNP-AAP) were used, for the first time, to covalently bond rose bengal (SiNP-AAP-RB) or 9,10-anthraquinone-2-carboxylic acid (SiNP-AAP-OCAq). The functionalized SiNP were characterized by: Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM); elemental analysis (CHN) for determination of the dye concentration; FTIR and UV-vis diffuse reflectance (DR-UV-vis) and a surface area study (BET). The functionalized SiNPs were applied in photodynamic therapy (PDT) against lung cancer cell lines. The evaluated cytotoxicity revealed 20-30% cell survival after 15min of PDT for both materials but the OCAq concentration was half of the RB nanomaterial. The phototoxicity was mainly related to oxidative stress generated in the cellular environment by singlet oxygen and by hydrogen abstraction as confirmed by the laser flash photolysis technique. The unprecedented results indicate that SiNP-AAP-OCAq is a possible system for promoting cell apoptosis by both type I and type II mechanisms.


Assuntos
Antraquinonas/administração & dosagem , Portadores de Fármacos , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Fármacos Fotossensibilizantes/administração & dosagem , Dióxido de Silício/química , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Antraquinonas/uso terapêutico , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/parasitologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Fármacos Fotossensibilizantes/uso terapêutico , Rosa Bengala/análise , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Opt Express ; 20(13): 13669-76, 2012 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-22714432

RESUMO

The two-photon excited fluorescence (TPEF) increments of two dyes via bovine serum albumin (BSA) microstructures fabricated by the two-photon crosslinking technique were investigated. One is Rose Bengal (RB) with a high non-radiative decay rate, while the other is Eosin Y with a low non-radiative decay rate. Experimental results demonstrate that the quantum yield and lifetime of RB are both augmented via crosslinked BSA microstructures. Compared with theoretical analysis, this result indicates that the non-radiative decay rate of RB is decreased; hence, the quenched effect induced by BSA solution is suppressed. However, the fluorescence lifetime of Eosin Y is acutely abated despite the augmented quantum yield for the two-photon crosslinking processing from BSA solution. This result deduces that the radiative decay rate increased. Furthermore, the increased TPEF intensity and lifetime of RB correlated with the concentration of fabricated crosslinked BSA microstructures through pulse selection of the employed femtosecond laser is demonstrated and capable of developing a zone-plate-like BSA microstructure.


Assuntos
Amarelo de Eosina-(YS)/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Rosa Bengala/química , Soroalbumina Bovina/análise , Soroalbumina Bovina/química , Reagentes para Ligações Cruzadas/análise , Reagentes para Ligações Cruzadas/química , Amarelo de Eosina-(YS)/análise , Rosa Bengala/análise
3.
Mol Vis ; 17: 2847-55, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22128232

RESUMO

PURPOSE: To test the hypotheses that pregnancy represents a physiologic condition that is associated with dry eye symptoms, and the expression of aquaporin 4 (AQP4) and AQP5 are altered in the lacrimal gland (LG) from term pregnant rabbits. METHODS: Schirmer's test, tear break-up time (BUT), and Rose Bengal staining were used to evaluate ocular surface health. LG were obtained from term pregnant rabbits and age-matched female control rabbits and then processed for laser capture microdissection (LCM), real time RT-PCR, western blot, and immunofluorescence for the detection and quantification of mRNA and proteins of AQP4 and AQP5. RESULTS: Pregnant rabbits demonstrated typical clinical symptoms of dry eye, including decreased Schirmer score and BUT as well as increased Rose Bengal staining of cornea. In term pregnant rabbits, mRNA for AQP5 from whole LG was significantly lower than that of control rabbits, while mRNA for AQP4 was not. Levels of mRNA for AQP4 and AQP5 underwent significant changes in acini and epithelial cells from specific duct segments during pregnancy. Western blot from whole LG lysates demonstrated that expression of AQP4 was 24% more abundant in term pregnant rabbits while AQP5 was 22% less when compared to control rabbits respectively. At term pregnancy, AQP4 immunoreactivity (AQP4-IR) was increased in acini while its intensity remained the same in ducts. AQP5-IR was present in both apical and basolateral membranes of acinar cells in normal control and pregnant rabbits, while ductal cells in pregnant rabbits also showed significant amount of AQP5-IR. CONCLUSIONS: The data presented here demonstrated significant dry eye symptoms in pregnant rabbits. Our data also showed altered expressions of AQP4 and AQP5 during pregnancy and suggested that these changes may contribute to the altered LG secretion and dry eye symptoms during pregnancy.


Assuntos
Aquaporina 4/metabolismo , Aquaporina 5/metabolismo , Síndromes do Olho Seco/metabolismo , Aparelho Lacrimal/metabolismo , Complicações na Gravidez/metabolismo , Lágrimas/metabolismo , Células Acinares/citologia , Células Acinares/metabolismo , Animais , Aquaporina 4/genética , Aquaporina 5/genética , Western Blotting , Córnea/metabolismo , Córnea/patologia , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/patologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Imunofluorescência , Expressão Gênica , Aparelho Lacrimal/patologia , Microdissecção e Captura a Laser , Gravidez , Complicações na Gravidez/genética , Complicações na Gravidez/patologia , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rosa Bengala/análise
4.
Anal Bioanal Chem ; 394(7): 1965-75, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19543717

RESUMO

This article describes the use of the net analyte signal (NAS) concept and rank annihilation factor analysis (RAFA) for building two different multivariate standard addition models called "SANAS" and "SARAF." In the former, by the definition of a new subspace, the NAS vector of the analyte of interest in an unknown sample as well as the NAS vectors of samples spiked with various amounts of the standard solutions are calculated and then their Euclidean norms are plotted against the concentration of added standard. In this way, a simple linear standard addition graph similar to that in univariate calibration is obtained, from which the concentration of the analyte in the unknown sample and the analytical figures of merit are readily calculated. In the SARAF method, the concentration of the analyte in the unknown sample is varied iteratively until the contribution of the analyte in the response data matrix is completely annihilated. The proposed methods were evaluated by analyzing simulated absorbance data as well as by the analysis of two indicators in synthetic matrices as experimental data. The resultant predicted concentrations of unknown samples showed that the SANAS and SARAF methods both produced accurate results with relative errors of prediction lower than 5% in most cases.


Assuntos
Antraquinonas/análise , Compostos de Cetrimônio/análise , Rosa Bengala/análogos & derivados , Antraquinonas/normas , Calibragem , Cetrimônio , Compostos de Cetrimônio/normas , Interpretação Estatística de Dados , Análise Fatorial , Análise Multivariada , Padrões de Referência , Rosa Bengala/análise , Rosa Bengala/normas , Espectrofotometria Ultravioleta
5.
Shokuhin Eiseigaku Zasshi ; 50(1): 6-9, 2009 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-19325219

RESUMO

A simple and rapid method using electron capture detector gas chromatography (GC-ECD) was developed for the determination of hexachlorobenzene (HCB) in Food Red Nos. 104 and 105. The sample was dissolved in water and HCB was extracted with hexane. The GC-ECD operating conditions were as follows: column, InertCap 5 MS/NP (30 m x 0.25 mm i. d. with 0.25 microm film thickness); oven temperature, 60 degrees C(1 min)-->20 degrees C/min-->150 degrees C(10 min)-->20 degrees C/min-->280 degrees C(5 min); inlet temperature, 260 degrees C; detector temperature, 300 degrees C; carrier gas, nitrogen (constant press 25 psi); inlet mode, splitless. For the evaluation of the method, HCB spiked into R104 and R105 at the levels of 2 microg/g and 5 microg/g was determined in replicate in five laboratories. Mean recoveries of HCB from R104 and R105 were 98.2-103.7%. Repeatability relative standard deviation values were 2.9-6.0% and reproducibility relative standard deviation values were 4.2-9.3%. HORRAT value was less than one. From these results, the validity of this method was confirmed.


Assuntos
Cromatografia Gasosa/métodos , Corantes de Alimentos/análise , Hexaclorobenzeno/análise , Rosa Bengala/análise , Eletroquímica/métodos
6.
Histochem Cell Biol ; 128(5): 485-95, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17849139

RESUMO

Rose Bengal (RB) is a very efficient photosensitizer which undergoes inactivation of its photophysical and photochemical properties upon addition of a quencher group-i.e. acetate-to the xanthene rings. The resulting RB acetate (RB-Ac) derivative behaves as a fluorogenic substrate: it easily enters the cells where the native photoactive molecule is restored by esterase activities. It is known that the viability of RB-Ac-loaded cells is strongly reduced by light irradiation, attesting to the formation of intracellular RB. The aim of this study was to identify the organelles photodamaged by the intracellularly formed RB. RB-Ac preloaded rat C6 glioma cells and human HeLa cells were irradiated at 530 nm. Fluorescence confocal imaging and colocalization with specific dyes showed that the restored RB molecules redistribute dynamically through the cytoplasm, with the achievement of a dynamic equilibrium at 30 min after the administration, in the cell systems used; this accounted for a generalized damage to several organelles and cell structures (i.e. the endoplasmic reticulum, the Golgi apparatus, the mitochondria, and the cytoskeleton). The multiple organelle damage, furthermore, led preferentially to apoptosis as demonstrated by light and electron microscopy and by dual-fluorescence staining with FITC-labelled annexin V and propidium iodide.


Assuntos
Apoptose , Corantes Fluorescentes/toxicidade , Fármacos Fotossensibilizantes/toxicidade , Rosa Bengala/análogos & derivados , Animais , Células HeLa , Humanos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Organelas/efeitos dos fármacos , Ratos , Rosa Bengala/análise , Rosa Bengala/toxicidade , Raios Ultravioleta
7.
Shokuhin Eiseigaku Zasshi ; 46(3): 93-8, 2005 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-16042295

RESUMO

Hajikami (ginger pickled in vinegar) is often used as a relish for grilled fish, and it often contains coloring agents. We detected Rose Bengal (R105) and two unknown dyes in some Hajikami by thin layer chromatography. In this study, we tried to characterize these unknown dyes by HPLC with photodiode array detection (PDA-HPLC), liquid chromatography/mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). PDA-HPLC analysis showed that the spectra of the unknown dyes resembled that of R105, suggesting the molecular structures of these two dyes are similar to that of R105. Furthermore, LC/MS analysis suggested that the these dyes are R105 in which one or two iodines are replaced by hydrogen. Finally, the two dyes were determined by 1H-NMR and 13C-NMR to be 4,5,6,7-tetrachloro-3',6'-dihydroxy-2',7'-diiodo spiro[isobenzofuran- 1 (3H),9'-[9H]xanthen]-3-one disodium salt and 4,5,6,7-tetrachloro-3',6'-dihydroxy-2',7'-diiodo spiro[isobenzofuran-1(3H),9'[9H]xanthen]-3-one disodium salt.


Assuntos
Corantes/química , Análise de Alimentos , Gengibre/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Corantes/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Rosa Bengala/análise
9.
Sci China C Life Sci ; 48(6): 540-50, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16483133

RESUMO

There is increasing evidence for considerable interlinking between the responses to heat stress and oxidative stress, and recent researches suggest heat shock transcription factors (Hsfs) play an important role in linking heat shock with oxidative stress signals. In this paper, we present evidence that AtHsfA2 modulated expression of stress responsive genes and enhanced tolerance to heat and oxidative stress in Arabidopsis. Using Northern blot and quantitative RT-PCR analysis, we demonstrated that the expression of AtHsfA2 was induced by not only HS but also oxidative stress. By functional analysis of AtHsfA2 knockout mutants and AtHsfA2 overexpressing transgenic plants, we also demonstrated that the mutants displayed reduced the basal and acquired thermotolerance as well as oxidative stress tolerance but the overexpression lines displayed increased tolerance to these stress. The phenotypes correlated with the expression of some Hsps and APX1, ion leakage, H202 level and degree of oxidative injuries. These results showed that, by modulated expression of stress responsive genes, AtHsfA2 enhanced tolerance to heat and oxidative stress in Arabidopsis. So we suggest that AtHsfA2 plays an important role in linking heat shock with oxidative stress signals.


Assuntos
Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/fisiologia , Temperatura Alta/efeitos adversos , Estresse Oxidativo/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Arabidopsis/citologia , Proteínas de Arabidopsis/biossíntese , Ascorbato Peroxidases , Northern Blotting/métodos , Membrana Celular/fisiologia , Proteínas de Ligação a DNA/análise , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico/análise , Proteínas de Choque Térmico/biossíntese , Peróxido de Hidrogênio/farmacologia , Mutação/genética , Permeabilidade , Peroxidases/biossíntese , Proteínas de Plantas/análise , Plantas Geneticamente Modificadas , RNA Mensageiro/isolamento & purificação , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rosa Bengala/análise , Plântula/efeitos dos fármacos , Sobrevida , Fatores de Transcrição/análise
10.
Arq. ciênc. vet. zool. UNIPAR ; 7(2): 157-162, jul.-dez. 2004. ilus, tab
Artigo em Português | LILACS | ID: lil-418093

RESUMO

A análise da morfologia dos espermatozóides do sêmen colhido de 30 pacus (Piaractus mesopotamicus) consistiu de três soluções fixadoras: formol salina tamponada (FS), citrato sódio diidratado a 3% (CS) e água destilado (Ag) e para corar as células espermáticas três corantes: Vermelho Congo (VC), Rosa Bengala (RB) e Williams-modificado (WM). As combinações de corantes e soluções fixadoras utilizadas foram: RB X FS, WM X FS, VC X FS, VC X Ag, WM X Ag, WM X CS e VC X CS. Na avaliação dos esfregaços levaram-se em consideração as alterações anatômicas, a eficiência do corante, a aglutinação e a sujidade. Quando o sêmen foi diluído em CS e Ag, os espermatozóides sofreram alterações anatômicas e aglutinação, inviabilizando a análise. O FS não gerou alteração anatômica e nem aglutinação dos espermatozóides, sendo possível avaliar a eficiência do corante. Ao analisar a combinação RB X FS verificou-se a melhor média estimada de 9,97 pontos (P<0,05), com baixa sujidade e boa eficiência do corante. A combinação WM X FS resultou na média estimada de 7,35 pontos e a do VC X FS de 6,83 pontos que foram valores menores (P<0,05) em comparação aos esfregaços da combinação RB X FS. De acordo com os resultados obtidos neste estudo, a combinação do RB X FS apresentou os melhores resultados, sendo recomendado preparar esfregaços para analisar a morfologia dos espermatozóides de pacus (Piaractus mesopotamicus).


Assuntos
Animais , Pesqueiros , Rosa Bengala/análise , Sêmen , Vermelho Congo/análise
11.
DNA Repair (Amst) ; 3(12): 1601-15, 2004 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-15474421

RESUMO

8-Oxoguanine DNA glycosylase (OGG1) is a major DNA repair enzyme in mammalian cells. OGG1 participates in the repair of 8-oxoG, the most abundant known DNA lesion induced by endogenous reactive oxygen species in aerobic organisms. In this study, antibodies directed against purified recombinant human OGG1 (hOGG1) or murine (mOGG1) protein were chemically conjugated to either the photosensitizer Rose Bengal or the fluorescent dye Texas red. These dye-protein conjugates, in combination with binding assays, were used to identify associations between mOGG1 and the cytoskeleton of NIH3T3 fibroblasts. Results from these binding studies showed that mOGG1 associates with the cytoskeleton by specifically binding to the centriole and microtubules radiating from the centrosome at interphase and the spindle assembly at mitosis. Similar results were obtained with hOGG1. Together results reported in this study suggest that OGG1 is a microtubule-associated protein itself or that OGG1 utilizes yet to be identified motor proteins to ride on microtubules as tracks facilitating the movement and redistribution of cytoplasmic OGG1 pools during interphase and mitosis and in response to oxidative DNA damage.


Assuntos
Ciclo Celular/fisiologia , DNA Glicosilases/metabolismo , Microtúbulos/metabolismo , Animais , Anticorpos/química , Anticorpos/imunologia , Ligação Competitiva , Centríolos/imunologia , Centríolos/metabolismo , DNA Glicosilases/análise , Fibroblastos/citologia , Fibroblastos/imunologia , Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Humanos , Interfase/fisiologia , Camundongos , Microtúbulos/imunologia , Mitose/fisiologia , Células NIH 3T3 , Fotólise , Rosa Bengala/análise , Rosa Bengala/química , Fuso Acromático/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Xantenos/análise , Xantenos/química
12.
Zhonghua Yan Ke Za Zhi ; 38(2): 76-80, 2002 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-11955304

RESUMO

OBJECTIVE: To investigate the early changes of tear film after laser in situ keratomileusis (LASIK). METHODS: One hundred and forty-eight myopic eyes that underwent LASIK were randomly chosen. The eyes were observed for subjective complaints of dry eye, fluorescein staining (Fl), rose bengal staining (Rb), tear break-up time (BUT), Schirmer's I test preoperatively and 1 day, 1 week, 1 month, 3 months postoperatively. RESULTS: The subjective complaints of dry eye were more severe after the operation. There were obvious decreases in BUT at 1 day, 1 week, 1 month and 3 months postoperatively relative to the preoperative level (P < 0.05). The Schirmer's I test result was higher at 1 day but without statistical significance (P > 0.05), but lower at 1 week, 3 months (P < 0.05) after LASIK. No changes were observed in Schirmer's I test between preoperative and 1 month postoperative value (P > 0.05). Rb and Fl staining dots were more concentrated at 1 day and 1 week postoperatively (P < 0.0127). No significant changes were found in Rb staining at 1 month and 3 months postoperatively. CONCLUSION: LASIK does have some effects on tear film.


Assuntos
Síndromes do Olho Seco/etiologia , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Miopia/cirurgia , Complicações Pós-Operatórias , Lágrimas/metabolismo , Adolescente , Adulto , Córnea/patologia , Córnea/cirurgia , Feminino , Fluoresceína/análise , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Aparelho Lacrimal/fisiopatologia , Masculino , Rosa Bengala/análise
13.
Rev. peru. enf. infec. trop ; 1(2): 84-86, abr.-jun. 2001. tab
Artigo em Espanhol | PERNAL | ID: pnc-6175

RESUMO

Propósito: Conocer el impacto de la brucellosis en los Bancos de Sangre. Materiales y Métodos: Se realizó la prueba de Rosa de Bengala a 194 donantes de sangre de Lima y Callao. Resultados: Cinco personas presentaron serología positiva Brucella (2,58 por ciento) de los cuales uno corresponde al Callao (3,6 por ciento), tres a Barranca (2,9 por ciento), uno a Supe (3,0 por ciento) y ninguno a Paramonga. De los 100 donantes voluntarios, ninguno fue positivo a Brucella, en tanto que de los 94 donantes por reposición cinco (5,3 por ciento) fueron positivos. Discusión: Se evidencia que entre los donantes de sangre existen portadores de brucellosis que, eventualmente, podrían transmitir esta enfermedad a los que reciben esta sangre contaminada. En los donantes voluntarios, no se encuentra caso alguno. Esto amerita más estudios a fin de verificar lo anteriormente obtenido, así como investigar si se presentaron casos de Brucellosis post-transfusional. (AU)


Assuntos
Brucelose/tratamento farmacológico , Brucelose/epidemiologia , Brucelose/terapia , Brucelose/prevenção & controle , Rosa Bengala/análise , Bancos de Sangue
14.
Vet Microbiol ; 66(3): 223-33, 1999 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-10227124

RESUMO

Eight heifers were orally infected with 4 x 10(9) colony forming units of a field cattle strain of Yersinia enterocolitica O:9 in a capsule, 5 days a week, for about 9 weeks (day 0-day 64 (D0-D64). The faecal shedding of Y. enterocolitica O:9 began on D5 for seven out of the eight challenged cattle with a high level of excretion during the first month, followed by a decrease till the day of slaughter (D76). Y. enterocolitica O:9 was not isolated from organs collected at slaughter. No clinical symptoms were observed. Hyperplasia of intestinal lymph formations was the sole microscopic lesions observed. Five animals showed a serological reaction against Brucella antigens in at least one of the following tests: Rose-Bengal test, complement fixation test, tube agglutination test or indirect ELISA (iELISA) tests. Only one animal showed a high level of serological response and a positive reaction in the dithiothreitol-microagglutination test. The observed variability in terms of individual sensitivity to the Y. enterocolitica O:9 infection is in agreement with the low individual prevalence rate and the transient serological reaction and faecal Y. entercolitica O:9 shedding observed in herds showing false positive serological reactions in brucellosis.


Assuntos
Brucella/imunologia , Brucelose/veterinária , Doenças dos Bovinos/diagnóstico , Yersiniose/veterinária , Yersinia enterocolitica/imunologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/sangue , Brucelose/diagnóstico , Bovinos , Contagem de Colônia Microbiana , Testes de Fixação de Complemento/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Reações Falso-Positivas , Fezes/microbiologia , Feminino , Corantes Fluorescentes/análise , Rosa Bengala/análise , Yersiniose/diagnóstico
15.
J Mol Cell Cardiol ; 31(1): 113-21, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10072720

RESUMO

There is increasing evidence that reactive oxygen species (ROS) contribute to post-ischemic reperfusion injury, but determination of the specific ROS involved has proven elusive. In the present study electron paramagnetic resonance (EPR) spectroscopy was used in vitro to measure the relative quenching of singlet oxygen (1O2) by histidine and carnosine (beta-alanyl-L-histidine) utilizing the hindered secondary amine 2,2,6,6-tetramethyl-4-piperidone HCl (4-oxo-TEMP). The relative effect of histidine and carnosine on functional recovery of isolated perfused rat hearts was also studied. Functional recovery was measured by left ventricular developed pressure (LVDP), first derivative of left ventricular pressure (dP/dt), heart rate (HR) and coronary flow (CF). EPR measurements and Stern-Volmer plots showed that 400 microM carnosine quenched 1O2 twice as effectively as equimolar histidine in vitro. Moreover, 10 mM histidine improved functional recovery of isolated rat hearts significantly more than 1 mM histidine. Furthermore, 1 mM carnosine improved functional recovery significantly more than equimolar histidine and as effectively as 10 mM histidine. Experiments with 1 mM mannitol, a known hydroxyl radical scavenger, did not show an improvement in functional recovery relative to control hearts, thereby decreasing the likelihood that hydroxyl radicals are the major damaging species. On the other hand, the correlation between improved functional recovery of isolated rat hearts with histidine and carnosine and their relative 1O2 quenching effectiveness in vitro provides indirect evidence for 1O2 as ROS participating in reperfusion injury.


Assuntos
Carnosina/uso terapêutico , Histidina/uso terapêutico , Traumatismo por Reperfusão/terapia , Animais , Vasos Coronários/efeitos dos fármacos , Óxidos N-Cíclicos/análise , Relação Dose-Resposta a Droga , Etanol/farmacologia , Corantes Fluorescentes/análise , Frequência Cardíaca/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Manitol/farmacologia , Miocárdio/química , Óxido Nítrico/análise , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Recuperação de Função Fisiológica , Rosa Bengala/análise , Azida Sódica/farmacologia , Fatores de Tempo , Função Ventricular Esquerda/efeitos dos fármacos
16.
Toxicol Lett ; 84(1): 13-22, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8597173

RESUMO

Changes in hepatic paracellular permeability were investigated during the development of cholephilic dye-induced cholestasis in rats. For this purpose, four dyes with different cholestatic potency (phenol red, sulfobromophthalein, bromcresol green and rose bengal) were infused at a high, potentially damaging dose (280 nmol/min per 100 g body wt., i.v.), and changes in paracellular permeability were continuously monitored by measuring the access into bile of the permeability probe -14C-sucrose. The cholestatic potency of the different dyes was: rose bengal > bromcresol green > sulfobromophthalein > phenol red. All dyes increased [14C]sucrose bile-to-plasma ratio, producing a displacement towards curves of higher permeability. The capability of the dyes to increase biliary permeability followed the same order as their respective cholestatic potencies. The possible implications of the present results for cholephilic dye-induced cholestasis are discussed.


Assuntos
Sistema Biliar/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Colestase/induzido quimicamente , Corantes/toxicidade , Animais , Bile/química , Bile/fisiologia , Sistema Biliar/metabolismo , Verde de Bromocresol/administração & dosagem , Verde de Bromocresol/análise , Verde de Bromocresol/toxicidade , Colestase/metabolismo , Corantes/administração & dosagem , Injeções Intravenosas , Junções Intercelulares/metabolismo , Testes de Função Hepática , Masculino , Fenolsulfonaftaleína/administração & dosagem , Fenolsulfonaftaleína/análise , Fenolsulfonaftaleína/toxicidade , Ratos , Ratos Wistar , Rosa Bengala/administração & dosagem , Rosa Bengala/análise , Rosa Bengala/toxicidade , Sacarose/metabolismo , Sulfobromoftaleína/administração & dosagem , Sulfobromoftaleína/análise , Sulfobromoftaleína/toxicidade , Fatores de Tempo
17.
J Chromatogr A ; 680(2): 541-7, 1994 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-7981834

RESUMO

A method for the determination of synthetic tar dyes used as food additives using capillary electrophoresis with photodiode-array detection was investigated. The dyes Erythrosine (R-3), Phloxine (R-104), Rose Bengal (R-105), Acid Red (R-106), Amaranth (R-2), New Coccine (R-102) and Allura Red AC (R-40) were separated on a capillary column (50 cm x 75 microns I.D.) and identified from the absorbance spectra of each peak. The electrophoresis buffer used was a mixture of 25 mM sodium phosphate buffer and 25 mM sodium borate buffer (1:1) (pH 8.0) containing 10 mM sodium dodecyl sulfate (SDS). Substitution of beta-cyclodextrin for SDS in the electrolyte buffer was effective for the separation of R-2 and R-102. This modified method could be employed as an additional assay method for these two dyes.


Assuntos
Eletroforese/métodos , Corantes de Alimentos/análise , Corante Amaranto/análise , Compostos Azo/análise , Tampões (Química) , Ação Capilar , Eritrosina/análise , Fluoresceínas/análise , Japão , Naftalenossulfonatos , Rodaminas/análise , Rosa Bengala/análise
18.
s.l; Instituto de Pesquisas Energéticas e Nucleares; set. 1985. 8 p. tab.(Publicaçäo IPEN, 79).
Monografia em Inglês | LILACS | ID: lil-45597

RESUMO

Desenvolvem-se um sistema rápido de cromatografia miniaturizada para controle radioquímico de Rosa Bengala-131/ e Bromossulfaleina 131/ utilizando como solvente uma soluçäo aquosa de sulfato de amônio 33%, pH 7,5. Os compostos marcados permanecem na origem enquanto os íons iodeto e iodato migram com Rf 0,5 e 0,9, respectivamente


Assuntos
Cromatografia/métodos , Rosa Bengala/análise , Sulfobromoftaleína/análise
20.
Rev Sci Instrum ; 50(3): 333, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18699502

RESUMO

A simple experimental approach to measuring fluorescence decay by time correlation signal analysis is described. The approach allows the use of continuous wave excitation and inexpensive detection-signal processing apparatus. The technique is demonstrated using a cw He-Cd laser. The transient response of the instrument is 0.88 ns, limited by the photomultipliers. The fluorescence lifetime of rose bengal in ethanol is determined, in absence of reorientation relaxation, to be 0.66+/-0.04 ns.


Assuntos
Fluorescência , Lasers , Cádmio/química , Desenho de Equipamento , Etanol/química , Análise de Fourier , Hélio/química , Luz , Modelos Estatísticos , Rosa Bengala/análise , Processamento de Sinais Assistido por Computador , Fatores de Tempo
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