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1.
Cytometry B Clin Cytom ; 72(3): 211-4, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17266148

RESUMO

BACKGROUND: Erythrocyte morphology has already been studied in essential hypertension (EH) and cell membrane alterations have been observed. Relationships among red cell rheological, biochemical, and morphological properties still appear complex and are not clearly understood. METHODS: Erythrocyte morphology study was carried out by using the novel automated method we have recently developed. The morphometric parameters derived from optical microscope images were elaborated with image processing software (NIH Scion Image) to construct an application for the principal component analysis (PCA) to achieve a reliable and objective statistical method that would discriminate among erythrocyte morphologies of the considered groups. Three groups of subjects were studied: healthy (n = 30), healthy with familial EH (n = 25), and EH suffering subjects (n = 26). RESULTS: Our results show that morphological modifications are evident in both erythrocytes from EH and from healthy with familial EH subjects as compared to the controls. PCA showed remarkable morphological alterations in EH patients. In fact, the PCA explains for the 86.271% of the total variance that can be considered an excellent result. CONCLUSIONS: The results suggest that the use of this automated easy and inexpensive method for the detection of cell shape abnormalities is of high value in the early EH prediction.


Assuntos
Forma Celular , Técnicas Citológicas/métodos , Eritrócitos/citologia , Hipertensão/diagnóstico , Processamento de Imagem Assistida por Computador , Adulto , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Software
2.
Ann N Y Acad Sci ; 1091: 10-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17341598

RESUMO

It was long believed that melatonin might counteract intracellular oxidative stress because it was shown to potentiate antioxidant endogenous defences, and to increase the activity of many antioxidant enzymes. However, it is now becoming evident that when radicals are measured within cells, melatonin increases, rather than decreasing, radical production. Herein we demonstrate a pro-oxidant effect of melatonin in U937 cells by showing an increase of intracellular oxidative species and a depletion of glutathione (GSH). The activity of glutathione peroxidase is not modified by melatonin treatment as it does occur in other experimental models.


Assuntos
Glutationa Peroxidase/metabolismo , Glutationa/metabolismo , Líquido Intracelular/metabolismo , Melatonina/fisiologia , Oxidantes/fisiologia , Ativação Enzimática/fisiologia , Glutationa Peroxidase/fisiologia , Humanos , Líquido Intracelular/enzimologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Células U937
3.
Biochimie ; 85(10): 963-70, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14644551

RESUMO

The effects of the exposure to a static magnetic field (sMF) of 0.3 +/- 0.03 T on the Fusarium culmorum were investigated in vitro. sMF inhibition of mycelia growth was accompanied by morphological and biochemical changes. Fungal conidia germination and cell viability were also reduced. We provide evidence of the influence of sMF on Ca(2+)-dependent signal transduction pathways involved in conidia germination. Perturbation of these pathways by adding different compounds (i.e. CaCl(2), phorbol 12-myristate 13-acetate, neomycin, EGTA, LiCl) to the medium, suggested that exposed conidia are unable to mobilise calcium from intracellular stores and that the hindered mechanism may be IP(3)-dependent.


Assuntos
Fusarium/crescimento & desenvolvimento , Magnetismo , Acetato de Tetradecanoilforbol/análogos & derivados , Cloreto de Cálcio/farmacologia , Ácido Egtázico/farmacologia , Fusarium/efeitos dos fármacos , Cloreto de Lítio/farmacologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Neomicina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
4.
Ann N Y Acad Sci ; 1171: 472-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19723091

RESUMO

We have shown that melatonin exerts a prooxidant activity in U937 cells, a tumor human promonocytic cell line. (1) Here we show that melatonin induces a strong canonical activation of NF-kappaB, inducing IkappaBalpha degradation and the consequential nuclear translocation of p50/p65 subunits. The timing of NF-kappaB activation overlaps with the timing of reactive oxygen species (ROS) production due to melatonin. Overexpression of dominant-negative IkappaB, which prevents a possible NF-kappaB activation, transformed melatonin in a proapoptotic molecule. These data indicate for the first time that melatonin can trigger NF-kappaB activation and might suggest a possible role for ROS induced by melatonin. Results indicate a possible involvement in the survival pathway of melatonin-generated ROS as secondary messengers.


Assuntos
Melatonina/farmacologia , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Western Blotting , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Proteínas I-kappa B/metabolismo , Espaço Intracelular/metabolismo , Melatonina/metabolismo , Inibidor de NF-kappaB alfa , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Oxidantes/metabolismo , Oxidantes/farmacologia , Ligação Proteica/efeitos dos fármacos , Células U937
5.
Cytometry A ; 69(4): 260-5, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16528721

RESUMO

BACKGROUND: Vibrio alginolyticus is known to enter into a viable but nonculturable (VBNC) state in response to environmental conditions unfavorable to the growth. Cells in VBNC condition pose a public health threat because they are potentially pathogenic. METHODS: We constructed a pathway for the identification of the most significant variables and the characterization of those variables able to discriminate the groups under investigation. Different parameters measured by the image processing software were chosen as the most representative of V. alginolyticus cell morphology (length index for dimension) and metabolic activity (density profile indexes). To detect relationships between the groups of treatment performed, we carried out a principal components analysis (PCA). RESULTS: The PCA analysis indicated that increasing coccoid shape transformation was related to both metabolic and dimension variations, delineating a well defined graph profile. Indeed, we discovered that specific morphological variations occur when cells in the culturable state pass into VBNC condition, namely comma-shaped culturable bacteria are converted into coccoid-shaped VBNC cells. The results were also supported by scanning electron microscopy analysis. CONCLUSIONS: This technique allows the analysis of a large number of vibrio samples in a short period of time. The obtained multiparameter information may complement genetic/molecular analyses facilitating, in an automatic fashion, further studies to evaluate the potential risk of this pathogen in the environment. It may also be a useful tool for large-scale cell biology studies and high content screening.


Assuntos
Fenômenos Fisiológicos Bacterianos , Processamento de Imagem Assistida por Computador/métodos , Análise de Componente Principal , Vibrio alginolyticus , Técnicas de Cultura , Microscopia Eletrônica de Varredura , Vibrio alginolyticus/classificação , Vibrio alginolyticus/isolamento & purificação , Vibrio alginolyticus/ultraestrutura
6.
Cytometry A ; 69(2): 75-85, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16419064

RESUMO

BACKGROUND: It is common knowledge that static magnetic fields (SMF) do not interact with living cells; thus, fewer studies of SMF compared with variable magnetic fields are carried out. However, evidence demonstrated that SMF affect cellular structures. To investigate the effect of exposure to increasing doses of SMF on cell morphology, human glioblastoma cells were exposed to SMF ranging between 80 and 3,000 G (8 and 300 mT). METHODS: Cell morphology of human glioblastoma cells, derived from a primary culture, was studied by electron and optic microscopy. FITC-phalloidin staining of actin filaments was also investigated. Finally, cell surface structure changes were detected by atomic force microscopy. RESULTS: Scanning electron microscopy demonstrated a dose-dependent cell shape modification, progressive cell detachment, loss of the long villi, and appearance of membrane roughness and blebs. FITC-phalloidin staining confirmed the villi retention and cell dimension decrease. At 3,000 G, the appearance of apoptotic morphology was also observed by transmission electron microscopy. Cell exposed to SMF showed different orientation and alignment when compared with nonexposed cells. The atomic force microscopy of the exposed cells' membrane surfaces demonstrated the disappearance of the ordered surface ripples and furrows typical of the unexposed cells, and the occurrence of surface membrane corrugation at increasing dose exposure CONCLUSIONS: Our experimental procedures demonstrated that exposure to SMF affects not only cell size, shape, and orientation but also human glioblastoma cells' membrane surfaces.


Assuntos
Membrana Celular/ultraestrutura , Polaridade Celular , Forma Celular , Tamanho Celular , Glioblastoma/patologia , Magnetismo , Apoptose , Linhagem Celular Tumoral , Extensões da Superfície Celular/ultraestrutura , Glioblastoma/ultraestrutura , Humanos , Microscopia , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Propriedades de Superfície
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