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1.
Artigo em Inglês | MEDLINE | ID: mdl-26464574

RESUMO

BACKGROUND: Venoms comprise mixtures of numerous bioactive compounds that have a wide range of pharmacologic actions. Toxins from venomous animals have attracted the attention of researchers because of their affinity for primary sites responsible for lethality and their efficacy at extremely low concentrations. The venoms of marine stingrays have not been extensively studied and limited data is available on them. The present study aims to evaluate the antiproliferative and biochemical properties of the venom obtained from a species of marine stingray (Dasyatis sephen) on human cervical cancer cell line HeLa. METHODS: The antiproliferative effect of D. sephen venom was determined by MTT assay, and the oxidative stress was determined by lipid peroxidation method along with assessment of changes in the enzymatic and non-enzymatic antioxidant status. We observed intracellular reactive oxygen species (ROS) levels by DCFH-DA method, mitochondrial membrane potential alterations by rhodamine 123 staining and apoptotic morphological changes by acridine orange/ethidium bromide dual staining method. RESULTS: D. sephen venom enhances lipid peroxidative markers such as thiobarbituric acid reactive substance, conjugated diene, and lipid hydroperoxide in HeLa cell lines. Stingray venom enhances the ROS levels, which is evidenced by the increased 2-7-diacetyl dichlorofluorescein fluorescence. Further, D. sephen venom treatment altered the mitochondrial membrane potential in HeLa cells. Additionally, we observed increased apoptotic morphological changes in D. sephen venom-treated groups. CONCLUSIONS: Dasyatis sephen venom exhibits potent antiproliferative effect on HeLa cell line and upon further purification it could be a promising antiproliferative agent.

2.
J. venom. anim. toxins incl. trop. dis ; 21: 41, 31/03/2015. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954762

RESUMO

BackgroundVenoms comprise mixtures of numerous bioactive compounds that have a wide range of pharmacologic actions. Toxins from venomous animals have attracted the attention of researchers because of their affinity for primary sites responsible for lethality and their efficacy at extremely low concentrations. The venoms of marine stingrays have not been extensively studied and limited data is available on them. The present study aims to evaluate the antiproliferative and biochemical properties of the venom obtained from a species of marine stingray (Dasyatis sephen) on human cervical cancer cell line HeLa.MethodsThe antiproliferative effect of D. sephen venom was determined by MTT assay, and the oxidative stress was determined by lipid peroxidation method along with assessment of changes in the enzymatic and non-enzymatic antioxidant status. We observed intracellular reactive oxygen species (ROS) levels by DCFH-DA method, mitochondrial membrane potential alterations by rhodamine 123 staining and apoptotic morphological changes by acridine orange/ethidium bromide dual staining method.ResultsD. sephen venom enhances lipid peroxidative markers such as thiobarbituric acid reactive substance, conjugated diene, and lipid hydroperoxide in HeLa cell lines. Stingray venom enhances the ROS levels, which is evidenced by the increased 2-7-diacetyl dichlorofluorescein fluorescence. Further, D. sephen venom treatment altered the mitochondrial membrane potential in HeLa cells. Additionally, we observed increased apoptotic morphological changes in D. sephen venom-treated groups. ConclusionsDasyatis sephen venom exhibits potent antiproliferative effect on HeLa cell line and upon further purification it could be a promising antiproliferative agent.(AU)


Assuntos
Animais , Rajidae , Carcinoma , Estresse Oxidativo , Linhagem Celular
3.
J. venom. anim. toxins incl. trop. dis ; 21: 1-9, 31/03/2015. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484637

RESUMO

Background Venoms comprise mixtures of numerous bioactive compounds that have a wide range of pharmacologic actions. Toxins from venomous animals have attracted the attention of researchers because of their affinity for primary sites responsible for lethality and their efficacy at extremely low concentrations. The venoms of marine stingrays have not been extensively studied and limited data is available on them. The present study aims to evaluate the antiproliferative and biochemical properties of the venom obtained from a species of marine stingray (Dasyatis sephen) on human cervical cancer cell line HeLa.MethodsThe antiproliferative effect of D. sephen venom was determined by MTT assay, and the oxidative stress was determined by lipid peroxidation method along with assessment of changes in the enzymatic and non-enzymatic antioxidant status. We observed intracellular reactive oxygen species (ROS) levels by DCFH-DA method, mitochondrial membrane potential alterations by rhodamine 123 staining and apoptotic morphological changes by acridine orange/ethidium bromide dual staining method.ResultsD. sephen venom enhances lipid peroxidative markers such as thiobarbituric acid reactive substance, conjugated diene, and lipid hydroperoxide in HeLa cell lines. Stingray venom enhances the ROS levels, which is evidenced by the increased 27-diacetyl dichlorofluorescein fluorescence. Further, D. sephen venom treatment altered the mitochondrial membrane potential in HeLa cells. Additionally, we observed increased apoptotic morphological changes in D. sephen venom-treated groups. ConclusionsDasyatis sephen venom exhibits potent antiproliferative effect on HeLa cell line and upon further purification it could be a promising antiproliferative agent.


Assuntos
Humanos , Animais , Animais Venenosos , Peçonhas/uso terapêutico , Rajidae , Células HeLa/efeitos dos fármacos
4.
Methods Enzymol ; 509: 165-94, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22568906

RESUMO

Design of a unique, single-platform, integrated, multichannel sensor based on carbon nanotube (CNT)-protein adducts specific to each one of the major analytes of blood, glucose, cholesterol, triglyceride, and Hb1AC is presented. The concept underlying the sensor, amperometric detection, is applicable to various disease-monitoring strategies. There is an urgent need to enhance the sensitivity of glucometers to <5% level instead of greater than the present 15% standard in these detectors. CNTs enhance the signals derived from the interaction of the enzymes with the different analytes in blood. Fabricated sensors using the new methodology is a point-of-care device that is targeted for home, clinical, and emergency use and can be redesigned for continuous monitoring for critical care patients.


Assuntos
Técnicas Biossensoriais , Análise Química do Sangue/métodos , Nanotubos de Carbono , Aminoácido Oxirredutases/biossíntese , Aminoácido Oxirredutases/química , Glicemia/análise , Colesterol/sangue , Colesterol Oxidase/biossíntese , Colesterol Oxidase/química , Glucose Oxidase/biossíntese , Glucose Oxidase/química , Hemoglobinas Glicadas/metabolismo , Humanos , Proteínas Imobilizadas/biossíntese , Proteínas Imobilizadas/química , Dispositivos Lab-On-A-Chip , Lipase/biossíntese , Lipase/química , Microfluídica , Modelos Moleculares , Engenharia de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Esterol Esterase/biossíntese , Esterol Esterase/química , Propriedades de Superfície , Triglicerídeos/sangue
5.
Asian Pac J Allergy Immunol ; 14(2): 87-90, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9177821

RESUMO

The aim of this project was to compare dual and tri-colour reagents for lymphocyte immunophenotyping. A total of 37 patient and normal specimens were immunophenotyped concurrently with the following mean values (% dual vs tri-colour): CD3 (69.4 vs 68.3) CD4 (24.0 vs 24.2) and CD19 (13.9 vs 12.6). A comparison of the results obtained using the paired t test showed that there were no significant differences for cells expressing CD3, CD4 and CD19. However, there was a significant difference in the NK (18.3 vs 16.3) cell component. A major advantage in using 3 colour immunophenotyping is the ability to analyse specimens that cannot be analysed using dual colour reagents due to debris or contamination of the gate with non-lymphocytic cells.


Assuntos
Corantes , Indicadores e Reagentes , Subpopulações de Linfócitos/citologia , Antígenos CD19/análise , Complexo CD3/análise , Antígenos CD4/análise , Citometria de Fluxo/métodos , Antígenos HLA-DR/análise , Humanos , Células Matadoras Naturais/química , Células Matadoras Naturais/citologia , Subpopulações de Linfócitos/química
6.
Ann Acad Med Singap ; 24(6): 785-8, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8838981

RESUMO

A cross-sectional study on the expression of 6 lymphocyte markers was carried out on 481 patients with human immunodeficiency virus (HIV) and 79 normals after stratification based on absolute CD4 counts. The data were stratified according to the following groups: (I) 1201 to 1600, (II) 801 to 1200, (III) 401 to 800 and (IV) 0 to 400 (x 10(6) CD4 cells per mm3). The mean percentages of the subsets before stratification showed that HIV patients had increased percentages of CD3+ (75.7 against 66.9), CD3+CD8+ (52.2 against 32.3) and CD3+HLA-DR+ (36.1 against 14.4) cells and lower percentages of CD19 (10.3 against 13.3) and natural killer cells (13.7 against 20.4) when compared to controls in the same group. A definite trend, however, was only seen in CD3+CD8+ (47.4, 50.0, 54.0, 57.5 for groups I, II, III and IV respectively) and CD3+HLA-DR+ (29.1, 32.9, 38.4, 43.9 for groups I, II, III and IV respectively).


Assuntos
Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/patologia , Soropositividade para HIV/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Antígenos CD19/genética , Linfócitos B/patologia , Complexo CD3/genética , Antígenos CD8/genética , Linfócitos T CD8-Positivos/patologia , Estudos Transversais , Regulação da Expressão Gênica , Soropositividade para HIV/patologia , Antígenos HLA-DR/genética , Humanos , Células Matadoras Naturais/patologia , Contagem de Linfócitos , Estudos Retrospectivos , Linfócitos T/patologia , Linfócitos T Auxiliares-Indutores/patologia
7.
Singapore Med J ; 36(3): 288-91, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8553095

RESUMO

The aim of this study was to establish the lymphocyte subset reference ranges in a defined Malaysian population as well as to determine inter-racial differences for these values. Normal blood obtained from 152 subjects (55.9% Malay, 26.3% Chinese and 17.7% Indian) was immunophenotyped. Results obtained (expressed as mean +/- SD %), absolute count (x 10(6) cells/mm3) were as follows: CD3:66.5 +/- 8.6%, 2,066; CD4:33.2 +/- 8.5%, 1,028; CD831.6 +/- 8.9%, 982; CD19:12.0 +/- 0%, 5,374, and CD56+CD16:20.9 +/- 9%, 1,638. There were no significant differences between the percent lymphocyte subsets of the three racial groups. However, the absolute number of CD4 cells and CD19 cells in Chinese was significantly lower (p < 0.05) compared to the Indian and the Indian and Malay groups respectively. Comparison of our results with other reports showed that the percentage of Natural Killer cells in this population is higher than that reported for Caucasian population.


Assuntos
Povo Asiático , Subpopulações de Linfócitos/química , População Branca , Adolescente , Adulto , China/etnologia , Feminino , Humanos , Imunofenotipagem , Índia/etnologia , Malásia , Masculino , Pessoa de Meia-Idade , Valores de Referência
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