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1.
Sci Rep ; 12(1): 10894, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764793

RESUMO

Cerebrospinal fluid (CSF), a clear fluid bathing the central nervous system (CNS), undergoes pulsatile movements. Together with interstitial fluid, CSF plays a critical role for the removal of waste products from the brain, and maintenance of the CNS health. As such, understanding the mechanisms driving CSF movement is of high scientific and clinical impact. Since pulsatile CSF dynamics is sensitive and synchronous to respiratory movements, we are interested in identifying potential integrative therapies such as yogic breathing to regulate CSF dynamics, which has not been reported before. Here, we investigated the pre-intervention baseline data from our ongoing randomized controlled trial, and examined the impact of four yogic breathing patterns: (i) slow, (ii) deep abdominal, (iii) deep diaphragmatic, and (iv) deep chest breathing with the last three together forming a yogic breathing called three-part breath. We utilized our previously established non-invasive real-time phase contrast magnetic resonance imaging approach using a 3T MRI instrument, computed and tested differences in single voxel CSF velocities (instantaneous, respiratory, cardiac 1st and 2nd harmonics) at the level of foramen magnum during spontaneous versus yogic breathing. In examinations of 18 healthy participants (eight females, ten males; mean age 34.9 ± 14 (SD) years; age range: 18-61 years), we observed immediate increase in cranially-directed velocities of instantaneous-CSF 16-28% and respiratory-CSF 60-118% during four breathing patterns compared to spontaneous breathing, with the greatest changes during deep abdominal breathing (28%, p = 0.0008, and 118%, p = 0.0001, respectively). Cardiac pulsation was the primary source of pulsatile CSF motion except during deep abdominal breathing, when there was a comparable contribution of respiratory and cardiac 1st harmonic power [0.59 ± 0.78], suggesting respiration can be the primary regulator of CSF depending on the individual differences in breathing techniques. Further work is needed to investigate the impact of sustained training yogic breathing on pulsatile CSF dynamics for CNS health.


Assuntos
Respiração , Taxa Respiratória , Adolescente , Adulto , Feminino , Coração , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Adulto Jovem
2.
Mol Med Rep ; 22(2): 1400-1408, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32468007

RESUMO

Daphne altaica Pall. (D. altaica; Thymelaeaceae) has long been used in traditional Kazakh medicine for the treatment of cancer and respiratory diseases. Previous studies have demonstrated the in vitro anticancer effects of D. altaica extract and its constituents in certain cancer cell lines; however, the underlying molecular mechanisms are not completely understooD. The present study aimed to investigate the molecular mechanisms underlying the activity of an ethyl acetate extract of D. altaica (Da­Ea) by assessing its effects on cell morphology, cell apoptosis, cell cycle progression and the expression levels of peroxisome proliferator­activated receptor γ (PPARγ) in Eca­109 cells. Cell morphology was observed under a phase contrast microscope. Cell apoptosis and cell cycle progression were assessed by flow cytometry following Annexin V/propidium iodide (PI) double staining and PI single staining, respectively. The mRNA and protein expression levels of PPARγ were determined by reverse transcription­quantitative PCR and western blotting, respectively. Compared with the control group, the percentage of apoptotic cells, cell cycle arrest at S phase and apoptotic morphological cell characteristics were increased in Da­Ea­treated Eca­109 cells. Furthermore, Da­Ea treatment upregulated the mRNA and protein expression levels of PPARγ compared with the control cells. High­performance liquid chromatography with diode­array detection indicated that daphnetin­7­O­ß­D­glucoside, daphnetin, demethyldaphnoretin­7­O­ß­D­glucopyranoside and genkwanol A were the main constituents of Da­Ea. Collectively, the results suggested that Da­Ea displayed antiproliferative activities in Eca­109 cells by inducing apoptosis and S phase cell cycle arrest, as well as upregulating PPARγ expression levels.


Assuntos
Acetatos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Daphne/química , Neoplasias Esofágicas/metabolismo , PPAR gama/metabolismo , Casca de Planta/química , Extratos Vegetais/química , Acetatos/administração & dosagem , Acetatos/química , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Microscopia de Contraste de Fase , PPAR gama/genética , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Fase S/efeitos dos fármacos , Regulação para Cima
3.
Appl Opt ; 58(27): 7416-7423, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674390

RESUMO

The intracellular dynamics of onion epidermal cells during the dehydration process is observed by holographic microscopy. Both the nucleus and cytoplasm are accurately revealed by quantitative phase imaging while dehydration takes place. Indeed, we notice that the contrast of phase images increases with the decrease in cellular water content. We foresee that such a dehydrating process can be effective for improving phase contrast, thus permitting better imaging of plant cells with the scope of learning more about cellular dynamics and related phenomena. Exploiting this concept, we observe intracellular cytoplasmic circulation and transport of biological material.


Assuntos
Citoplasma/fisiologia , Holografia/métodos , Microscopia de Contraste de Fase/métodos , Cebolas/citologia , Células Vegetais/fisiologia , Água/fisiologia , Transporte Biológico/fisiologia , Desidratação , Epiderme Vegetal/fisiologia
4.
Sci Rep ; 8(1): 12017, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30104610

RESUMO

Synchrotron radiation microtomography (SRµCT) is a nominally non-destructive 3D imaging technique which can visualise the internal structures of whole soft tissues. As a multi-stage technique, the cumulative benefits of optimising sample preparation, scanning parameters and signal processing can improve SRµCT imaging efficiency, image quality, accuracy and ultimately, data utility. By evaluating different sample preparations (embedding media, tissue stains), imaging (projection number, propagation distance) and reconstruction (artefact correction, phase retrieval) parameters, a novel methodology (combining reversible iodine stain, wax embedding and inline phase contrast) was optimised for fast (~12 minutes), high-resolution (3.2-4.8 µm diameter capillaries resolved) imaging of the full diameter of a 3.5 mm length of rat spinal cord. White-grey matter macro-features and micro-features such as motoneurons and capillary-level vasculature could then be completely segmented from the imaged volume for analysis through the shallow machine learning SuRVoS Workbench. Imaged spinal cord tissue was preserved for subsequent histology, establishing a complementary SRµCT methodology that can be applied to study spinal cord pathologies or other nervous system tissues such as ganglia, nerves and brain. Further, our 'single-scan iterative downsampling' approach and side-by-side comparisons of mounting options, sample stains and phase contrast parameters should inform efficient, effective future soft tissue SRµCT experiment design.


Assuntos
Imageamento Tridimensional/métodos , Medula Espinal/diagnóstico por imagem , Coloração e Rotulagem/métodos , Microtomografia por Raio-X/métodos , Animais , Imageamento Tridimensional/instrumentação , Masculino , Microscopia de Contraste de Fase , Ratos , Síncrotrons , Fatores de Tempo , Inclusão do Tecido/métodos , Microtomografia por Raio-X/instrumentação
5.
Sci Rep ; 6: 39466, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-28008938

RESUMO

There are serious systemic infections associated with methicillin-resistant Staphylococcus aureus (MRSA) and several other types of bacteria leading to the deaths of millions of people globally. This type of mortality is generally caused by the increasing number of antibiotic-resistant organisms, a consequence of evolution via natural selection. After the synthesis of gold nanoparticles (GNPs) by wet chemistry, bio-functionalization with IgG molecules was performed. Following administration of IgG-GNPs to MRSA cultures at various concentrations and various incubation time laser irradiation was performed. To assess the selectivity and specificity of the proposed treatment the following methods were used: flow cytometry, contrast phase microscopy, and by fluorescence microscopy. The results in our study indicate that following administration of IgG-GNPs biomolecule an extended and selective bacterial death occurs following laser irradiation in a dose dependent manner. Therefore, the new findings might impel studies on these antibacterial nanomaterials and their biological and medical applications.


Assuntos
Ouro/química , Imunoglobulina G/química , Nanopartículas Metálicas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Antibacterianos/química , Separação Celular , Sobrevivência Celular , Sistemas de Liberação de Medicamentos , Citometria de Fluxo , Luz , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Confocal , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Nanocompostos/química , Espectrofotometria Ultravioleta
6.
Talanta ; 161: 368-376, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769419

RESUMO

Human dopaminergic system in general, and substantia nigra (SN) neurons, in particular, are implicated in the pathologies underlying the human brain aging. The interplay between aberrations in the structural organization and elemental composition of SN neuron bodies has recently gained in importance as selected metals: Fe, Cu, Zn, Ca were found to trigger oxidative-stress-mediated aberration in their molecular assembly due to concomitant protein (alpha-synuclein, tau-protein) aggregation, gliosis and finally oxidative stress. In the present study, we demonstrate an integrated approach to the analysis of the structural organization, assembly, and metals' accumulation in two distinct areas of SN: in the neuromelanin neurons and neuropil. By using the highly brilliant source of PETRA III and the Kirkpatrick-Baez nano-focus, large area histological brain slices are scanned at the sub-neuronal resolution, taking advantage of continuous motor movement and reduced acquisition time. Elemental analysis with synchrotron radiation based X-ray Fluorescence (SRXRF) is combined with X-ray Phase Contrast Imaging (XPCI) to correct for inherent aberrations in the samples' density and thickness, often referred to as the mass thickness effect. Based on the raw SRXRF spectra, we observed the accumulation of P, S, Cl, K, Ca, Fe, Cu and Zn predominantly in the SN neurons. However, upon the mass thickness correction, the distributions of Cl became significantly more uniform. Simultaneously with the fluorescence signal, the Small Angle X-ray Scattering (SAXS) is recorded by a pixel detector positioned in the far-field, enabling fast online computation of the darkfield and differential phase contrast (DPC). The data has demonstrated the SN neurons and neuropil produces excellent contrast which is due to their different mass density and scattering strength, indicative of differences in local structure and assembly therein. In all, the results show that combined SRXRF-XPCI-SAXS experiments can robustly serve as a unique tool for understanding the interplay between the chemical composition and structural organization that may drive the biochemical age-related processes occurring in the human dopaminergic system.


Assuntos
Neurônios/química , Neurônios/citologia , Substância Negra/química , Substância Negra/diagnóstico por imagem , Idoso , Cloro/análise , Humanos , Metais/análise , Microscopia de Contraste de Fase , Fósforo/análise , Espalhamento a Baixo Ângulo , Espectrometria por Raios X , Enxofre/análise , Raios X
7.
J Biol Inorg Chem ; 21(8): 1009-1020, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27696106

RESUMO

Osteosarcoma (OS) is the most common primary tumor of bone, occurring predominantly in the second decade of life. High-dose cytotoxic chemotherapy and surgical resection have improved prognosis, with long-term survival for patients with localized disease. Vanadium is an ultra-trace element that after being absorbed accumulates in bone. Besides, vanadium compounds have been studied during recent years to be considered as representative of a new class of non-platinum antitumor agents. Moreover, flavonoids are a wide family of polyphenolic compounds that display many interesting biological effects. Since coordination of ligands to metals can improve the pharmacological properties, we report herein, for the first time, the in vitro and in vivo effects of an oxidovanadium(IV) complex with the flavonoid chrysin on the new 3D human osteosarcoma and xenograft osteosarcoma mice models. The pharmacological results show that VOchrys inhibited the cell viability affecting the shape and volume of the spheroids and VOchrys suppressed MG-63 tumor growth in the nude mice without inducing toxicity and side effects. As a whole, the results presented herein demonstrate that the antitumor action of the complex was very promissory on human osteosarcoma models, whereby suggesting that VOchrys is a potentially good candidate for future use in alternative antitumor treatments.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Complexos de Coordenação/farmacologia , Flavonoides/farmacologia , Osteossarcoma/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Vanádio/farmacologia , Animais , Neoplasias Ósseas/patologia , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Feminino , Flavonoides/química , Humanos , Masculino , Camundongos Nus , Microscopia de Contraste de Fase , Estrutura Molecular , Osteossarcoma/patologia , Esferoides Celulares/patologia , Fatores de Tempo , Resultado do Tratamento , Vanádio/química , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Biochem Biophys Res Commun ; 479(2): 272-276, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27639647

RESUMO

A laboratory-based X-ray microscope is used to investigate the 3D structure of unstained whole pollen grains. For the first time, high-resolution laboratory-based hard X-ray microscopy is applied to study pollen grains. Based on the efficient acquisition of statistically relevant information-rich images using Zernike phase contrast, both surface- and internal structures of pine pollen - including exine, intine and cellular structures - are clearly visualized. The specific volumes of these structures are calculated from the tomographic data. The systematic three-dimensional study of pollen grains provides morphological and structural information about taxonomic characters that are essential in palynology. Such studies have a direct impact on disciplines such as forestry, agriculture, horticulture, plant breeding and biodiversity.


Assuntos
Pólen/ultraestrutura , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Pinus
9.
PLoS One ; 11(7): e0158963, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441372

RESUMO

INTRODUCTION: Phoenix dactylifera L (Date palm) is a native plant of the Kingdom of Saudi Arabia (KSA) and other Middle Eastern countries. Ajwa date has been described in the traditional and alternative medicine to provide several health benefits including anticholesteremic, antioxidant, hepatoprotective and anticancer effects, but most remains to be scientifically validated. Herein, we evaluated the anticancer effects of the Methanolic Extract of Ajwa Date (MEAD) on human breast adenocarcinoma (MCF7) cells in vitro. METHODS: MCF7 cells were treated with various concentrations (5, 10, 15, 20 and 25 mg/ml) of MEAD for 24, 48 and 72 h and changes in cell morphology, cell cycle, apoptosis related protein and gene expression were studied. RESULTS: Phase contrast microscopy showed various morphological changes such as cell shrinkage, vacuolation, blebbing and fragmentation. MTT (2-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay demonstrated statistically significant dose-dependent inhibitions of MCF7 cell proliferation from 35% to 95%. Annexin V-FITC and TUNEL assays showed positive staining for apoptosis of MCF7 cells treated with MEAD (15 mg and 25 mg for 48 h). Flow cytometric analyses of MCF7 cells with MEAD (15 mg/ml and 20 mg/ml) for 24 h demonstrated cell cycle arrest at 'S' phase; increased p53, Bax protein expression; caspase 3activation and decreased the mitochondrial membrane potential (MMP). Quantitative real time PCR (qRT-PCR) analysis showed up-regulation of p53, Bax, Fas, and FasL and down-regulation of Bcl-2. CONCLUSIONS: MEAD inhibited MCF7 cells in vitro by the inducing cell cycle arrest and apoptosis. Our results indicate the anticancer effects of Ajwa dates, which therefore may be used as an adjunct therapy with conventional chemotherapeutics to achieve a synergistic effect against breast cancer.


Assuntos
Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Phoeniceae/química , Extratos Vegetais/farmacologia , Adenocarcinoma/genética , Apoptose/genética , Neoplasias da Mama/genética , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Marcação In Situ das Extremidades Cortadas , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metanol , Microscopia de Contraste de Fase , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fase S/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
10.
Exp Eye Res ; 149: 75-83, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27327393

RESUMO

Low-level electrical stimulation to the eye has been shown to be neuroprotective against retinal degeneration in both human and animal subjects, using approaches such as subretinal implants and transcorneal electrical stimulation. In this study, we investigated the benefits of whole-eye electrical stimulation (WES) in a rodent model of retinitis pigmentosa. Transgenic rats with a P23H-1 rhodopsin mutation were treated with 30 min of low-level electrical stimulation (4 µA at 5 Hz; n = 10) or sham stimulation (Sham group; n = 15), twice per week, from 4 to 24 weeks of age. Retinal and visual functions were assessed every 4 weeks using electroretinography and optokinetic tracking, respectively. At the final time point, eyes were enucleated and processed for histology. Separate cohorts were stimulated once for 30 min, and retinal tissue harvested at 1 h and 24 h post-stimulation for real-time PCR detection of growth factors and inflammatory and apoptotic markers. At all time-points after treatment, WES-treated rat eyes exhibited significantly higher spatial frequency thresholds than untreated eyes. Inner retinal function, as measured by ERG oscillatory potentials (OPs), showed significantly improved OP amplitudes at 8 and 12 weeks post-WES compared to Sham eyes. Additionally, while photoreceptor segment and nuclei thicknesses in P23H-1 rats did not change between treatment groups, WES-treated eyes had significantly greater numbers of retinal ganglion cell nuclei than Sham eyes at 20 weeks post-WES. Gene expression levels of brain-derived neurotrophic factor (BDNF), caspase 3, fibroblast growth factor 2 (FGF2), and glutamine synthetase (GS) were significantly higher at 1 h, but not 24 h after WES treatment. Our findings suggest that WES has a beneficial effect on visual function in a rat model of retinal degeneration and that post-receptoral neurons may be particularly responsive to electrical stimulation therapy.


Assuntos
Terapia por Estimulação Elétrica/métodos , Degeneração Retiniana/terapia , Células Ganglionares da Retina/patologia , Visão Ocular/fisiologia , Animais , Modelos Animais de Doenças , Eletrorretinografia , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Microscopia de Contraste de Fase , Células Fotorreceptoras de Vertebrados/patologia , Ratos Endogâmicos Lew , Ratos Transgênicos , Degeneração Retiniana/metabolismo , Degeneração Retiniana/fisiopatologia
11.
Asian Pac J Cancer Prev ; 16(8): 3383-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25921149

RESUMO

Portulaca oleracea (Family: Portulacaceae), is well known for its anti-inflammatory, antioxidative, anti- bacterial, and anti-tumor activities. However, cytotoxic effects of seed oil of Portulaca oleracea against human liver cancer (HepG2) and human lung cancer (A-549) cell lines have not been studied previously. Therefore, the present study was designed to investigate the cytotoxic effects of Portulaca oleracea seed oil on HepG2 and A-549 cell lines. Both cell lines were exposed to various concentrations of Portulaca oleracea seed oil for 24h. After the exposure, percentage cell viability was studied by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT), neutral red uptake (NRU) assays, and cellular morphology by phase contrast inverted microscopy. The results showed a concentration-dependent significant reduction in the percentage cell viability and an alteration in the cellular morphology of HepG2 and A-549 cells. The percentage cell viability was recorded as 73%, 63%, and 54% by MTT assay and 76%, 61%, and 50% by NRU assay at 250, 500, and 1000 µg/ml, respectively in HepG2 cells. Percentage cell viability was recorded as 82%, 72%, and 64% by MTT assay and 83%, 68%, and 56% by NRU assay at 250, 500, and 1000 µg/ml, respectively in A-549 cells. The 100 µg/ml and lower concentrations were found to be non cytotoxic to A-549 cells, whereas decrease of 14% and 12% were recorded by MTT and NRU assay, respectively in HepG2 cells. Both HepG2 and A-549 cell lines exposed to 250, 500, and 1000 µg/ ml of Portulaca oleracea seed oil lost their normal morphology, cell adhesion capacity, become rounded, and appeared smaller in size. The data from this study showed that exposure to seed oil of Portulaca oleracea resulted in significant cytotoxicity and inhibition of growth of the human liver cancer (HepG2) and human lung cancer (A-549) cell lines.


Assuntos
Adenocarcinoma , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Hepáticas , Neoplasias Pulmonares , Óleos de Plantas/farmacologia , Portulaca , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Microscopia de Contraste de Fase , Vermelho Neutro , Sementes
12.
J BUON ; 20(6): 1487-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26854445

RESUMO

PURPOSE: Cervical carcinoma is the second most common malignancy in females and most of the cases are found in developing countries. The objectives of the present study were (a): to demonstrate the antiproliferative and apoptotic effects of Achillea falcata (A.falcata) extract in human cervical cancer cells (HeLa), and (b): to study the effect of the extract on cellular morphology, cell cycle phase distribution and mitochondrial membrane potential. METHODS: MTT assay was used to evaluate the anticancer effect of the extract on HeLa cells. Phase contrast, fluorescence microscopy and transmission electron microscopy (TEM) were used to investigate the morphological changes in these cancer cells after extract treatment. Flow cytometry was used to evaluate the effects of the extract on cell cycle and mitochondrial membrane potential. RESULTS: The results revealed that A. falcata extract led to a significant antiproliferative effect in HeLa cancer cells. The extract induced cellular shrinkage, chromatin condensation and appearance of apoptotic bodies which are the hallmarks of cellular apoptosis. TEM results showed that extract-treated cells had nuclear membrane which was hemispherical and the nuclear chromatin was concentrated and bundled on the inner border of karyotheca. The endoplasmic reticulum also became enlarged in the inner segment. The extract also induced G2/M phase cell cycle arrest along with loss of mitochondrial membrane potential. CONCLUSION: Achillea falcata extract induced potent antiproliferative and apoptotic effects in HeLa cells. This was accompanied by cellular shrinkage, chromatin condensation, G2/M phase cell cycle arrest and a loss of mitochondrial membrane potential in these cancer cells.


Assuntos
Achillea , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proliferação de Células/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Microscopia de Fluorescência , Microscopia de Contraste de Fase
13.
J Hazard Mater ; 284: 201-6, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25463234

RESUMO

The detoxification mechanism of asbestos materials was investigated through simulations and experiments. The permittivities of pure CaO and Mg3Si4O12, as quasi-asbestos materials, were measured using the cavity perturbation method. The real and imaginary parts of the relative permittivity (ɛr' and ɛr″) of CaO are functions of temperature, and numerical simulations revealed the thermal distributions in an electromagnetic field with respect to both asbestos shape and material configuration based on permittivity. Optical microscopic observation revealed that the thickness of chrysotile fibers decreased as a result of CaO heating. The heating mechanism of asbestos materials has been determined using CaO phase, and the detoxification mechanism of asbestos materials was discussed based on the heating mechanism.


Assuntos
Amianto/química , Compostos de Cálcio/química , Micro-Ondas , Óxidos/química , Asbestos Serpentinas/química , Simulação por Computador , Terremotos , Radiação Eletromagnética , Poluentes Ambientais/química , Temperatura Alta , Japão , Microscopia de Contraste de Fase , Óptica e Fotônica
14.
Andrologia ; 47(1): 52-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24387279

RESUMO

Flavonoids are major compounds of Aspalathus linearis and Camellia sinensis. They are classified as endocrine disruptors and some have been shown to inhibit testosterone production. TM3 Leydig cell cultures were treated with 250-5000 µg mL(-1) A. linearis (unfermented or fermented rooibos) or Camellia sinensis (green or black tea) for 24 h in the absence or presence of 6 mIU/200 µl human chorionic gonadotropin (hCG). Under nonstimulated conditions, all teas tend to decrease testosterone production (3.9-31.8%). However, under hCG-stimulation, a significant reduction in testosterone production was observed at all concentrations by both rooibos and tea (16.3-37.9%). MTT assay and phase contrast microscopy, revealed that at 250-1000 µg ml(-1) , both plants maintained the viability, proliferation and morphology of the cells, while 5000 µg ml(-1) was cytotoxic to the cells (P < 0.05). In conclusion, the results here demonstrate the anti-androgenic property of A. linearis and C. sinensis.


Assuntos
Aspalathus , Camellia sinensis , Células Intersticiais do Testículo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testosterona/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/patologia , Masculino , Camundongos , Microscopia de Contraste de Fase
15.
J Acupunct Meridian Stud ; 7(6): 337-45, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25499568

RESUMO

Because of the potential roles of the primo vascular system (PVS) in cancer metastasis, immune function, and regeneration, understanding the molecular biology of the PVS is desirable. The current state of PVS research is comparable to that of lymph research prior to the advent of Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1). There is very little knowledge of the molecular biology of the PVS due to difficulties in identifying and isolating primo endothelial cells. Present investigations rely on the morphology and the use of differential staining procedures to identify the PVS within tissues, making detailed molecular studies all but impossible. To overcome such difficulties, one may emulate the explosive development of lymph molecular biology. For this purpose, there is a need for a reliable method to obtain PVS specimens to initiate the molecular investigation. One of the most reliable methods is to detect the primo vessels and primo nodes afloat in the lymph flow. The protocols for observation of the PVS in the large lymph ducts in the abdominal cavity and the thoracic cavity were reported earlier. These methods require a laparectomy and skillful techniques. In this work, we present a protocol to identify and harvest PVS specimens from the lymph ducts connecting the inguinal and the axillary nodes, which are located entirely in the skin. Thus, the PVS specimen is more easily obtainable. This method is a stepping-stone toward development of a system to monitor migration of cancer cells in metastasis from a breast tumor to the axillary nodes, where cancer cells use the PVS as a survival rope in hostile lymph flow.


Assuntos
Vasos Linfáticos/anatomia & histologia , Meridianos , Azul Alciano/administração & dosagem , Azul Alciano/química , Animais , Masculino , Microscopia de Contraste de Fase , Ratos , Ratos Sprague-Dawley
16.
Appl Opt ; 53(31): 7230-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25402881

RESUMO

It is known that liquid crystal (LC) cells are useful as compact and easy-to-handle phase shifters that are readily coupled into the optics of standard microscope systems. Here, a uniformly aligned molecular LC phase shifter is introduced into a polarization microscope to attain a birefringence imaging system, using the phase-shift interferometric technique. Since the birefringence can be determined accurately only when the optical axis of the sample is parallel or perpendicular to the slow axis (variable axis) of the LC phase shifter, an improved data analysis method is proposed for determining the birefringence independently of the direction; a simple method of determining the slow axis distribution is also demonstrated. Measurements of the birefringence and slow axis distribution properties of a potato starch particle are demonstrated to confirm the novel determination method.


Assuntos
Interferometria/instrumentação , Cristais Líquidos/química , Microscopia de Contraste de Fase/instrumentação , Refratometria/instrumentação , Solanum tuberosum/química , Amido/química , Amido/ultraestrutura , Birrefringência , Desenho de Equipamento , Análise de Falha de Equipamento , Imagem Molecular/instrumentação
17.
PLoS One ; 9(1): e87127, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24489853

RESUMO

The ability to map the phase distribution and lateral coherence of an x-ray wavefront offers the potential for imaging the human body through phase contrast, without the need to deposit significant radiation energy. The classic means to achieve this goal is structured illumination, in which a periodic intensity modulation is introduced into the image, and changes in the phase distribution of the wavefront are detected as distortions of the modulation pattern. Two-dimensional periodic patterns are needed to fully characterize a transverse wavefront. Traditionally, the information in a 2D pattern is retrieved at high resolution by acquiring multiple images while shifting the pattern over a 2D matrix of positions. Here we describe a method to decode 2D periodic patterns with single-axis phase stepping, without either a loss of information or increasing the number of sampling steps. The method is created to reduce the instrumentation complexity of high-resolution 2D wavefront sensing in general. It is demonstrated with motionless electromagnetic phase stepping and a flexible processing algorithm in x-ray dark-field and phase contrast imaging.


Assuntos
Microscopia de Contraste de Fase/métodos , Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Hypericum/anatomia & histologia , Raios X
18.
J Cataract Refract Surg ; 40(2): 306-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24461502

RESUMO

PURPOSE: To evaluate the effect of complete destruction of lens epithelial cells (LECs) in the capsular bag on intraocular lens (IOL) stability. SETTING: School of Biological Sciences, University of East Anglia, Norwich, United Kingdom. DESIGN: Comparative evaluation. METHODS: An in vitro organ culture model using the bag-zonule-ciliary body complex isolated from fellow human donor eyes was prepared. A capsulorhexis and fiber extraction were performed, and an Acrysof IOL was implanted. Preparations were secured by pinning the ciliary body to a silicone ring and maintaining it in 6 mL Eagle minimum essential medium supplemented with 5% v/v fetal calf serum and 10 ng/mL transforming growth factor-ß2 for 3 weeks or more. One bag of each pair was treated with 1 µM thapsigargin to destroy all LECs. Observations of LEC growth were captured by phase-contrast microscopy, IOL stability by video microscopy, and endpoint analysis through scanning electron microscopy and immunocytochemistry. RESULTS: The LECs in control capsular bags migrated centrally, closing the bag and fixating the IOL between the anterior and posterior capsules, as seen clinically. These events were not observed in the thapsigargin-treated group. After a period of controlled orbital movement, the IOL in the control group stabilized quicker than in the treated bags. There was no IOL rotation in the bag; however, the IOLs in the treated group rocked with axial movement. CONCLUSIONS: The LECs appeared to aid stabilization of current IOL designs in the capsular bag. The results have clinical implications for IOL design and for strategies to prevent posterior capsule opacification. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Cápsula do Cristalino/cirurgia , Implante de Lente Intraocular , Cristalino/citologia , Tapsigargina/farmacologia , Idoso , Idoso de 80 Anos ou mais , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Opacificação da Cápsula/prevenção & controle , Morte Celular , Células Epiteliais/patologia , Feminino , Humanos , Imuno-Histoquímica , Lentes Intraoculares , Masculino , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Cápsula Posterior do Cristalino , Doadores de Tecidos
19.
Arch Pharm Res ; 37(2): 175-85, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23709168

RESUMO

The interaction of stem cell factor (SCF) with its cognate receptor c-Kit is closely associated with the survival and maturation of melanocytes. To investigate novel depigmentation agents, we screened 2,000 plant extracts for c-Kit inhibitors to identify active small molecules by using time-resolved fluorescence enzyme assays. For the active extracts identified as inhibitors of c-Kit enzyme, we evaluated the effects of the active extracts and isolated flavonoids on c-Kit phosphorylation in MO7e/melanocytes. Anti-melanogenic activity was also examined in melanocytes and melanoderm model. The flavonoids such as diosmetin, apigenin, acacetin and luteolin isolated from Chrysanthemum morifolium were found to be active in inhibiting c-Kit both at enzyme and cellular levels. In addition, these flavonoids attenuated SCF-induced proliferation of human primary melanocytes without toxicity and suppressed ultraviolet (UV) B irradiation-mediated melanin synthesis significantly. Among the active flavonoids, diosmetin was found to inhibit SCF-induced melanogenesis in a human melanoderm model. These results strongly suggest that C. morifolium extract and diosmetin have potential to suppress SCF-/UVB-induced melanogenesis, and could be developed as anti-pigmentation agents.


Assuntos
Chrysanthemum/química , Flavonoides/farmacologia , Melaninas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flores/química , Fluorimunoensaio , Humanos , Melaninas/biossíntese , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/efeitos da radiação , Camundongos , Microscopia de Contraste de Fase , Modelos Biológicos , Proteínas Proto-Oncogênicas c-kit/genética , Células Sf9 , Spodoptera , Fator de Células-Tronco/farmacologia , Fator de Células-Tronco/fisiologia , Raios Ultravioleta
20.
Opt Express ; 21(22): 25734-43, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24216799

RESUMO

Spectral domain phase microscopy for high-sensitive and broad-dynamic-range quantitative phase imaging is presented. The phase retrieval is realized in the depth domain to maintain a high sensitivity, while the phase information obtained in the spectral domain is exploited to extend the dynamic range of optical path difference. Sensitivity advantage of phase retrieved in the depth domain over that in the spectral domain is thoroughly investigated. The performance of the proposed depth domain phase based approach is illustrated by phase imaging of a resolution target and an onion skin.


Assuntos
Algoritmos , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Microscopia de Contraste de Fase/instrumentação , Microscopia de Contraste de Fase/métodos , Cebolas/citologia , Desenho de Equipamento , Análise de Falha de Equipamento , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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