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1.
Opt Lett ; 46(8): 1920-1923, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857104

RESUMO

X-ray microscopy offers the opportunity to image biological and radiosensitive materials without special sample preparations, bridging optical and electron microscopy capabilities. However, the performance of such microscopes, when imaging radiosensitive samples, is not limited by their intrinsic resolution, but by the radiation damage induced on such samples. Here, we demonstrate a novel, to the best of our knowledge, radio-efficient microscope, scanning Compton X-ray microscopy (SCXM), which uses coherently and incoherently (Compton) scattered photons to minimize the deposited energy per unit of mass for a given imaging signal. We implemented SCXM, using lenses capable of efficiently focusing 60 keV X-ray photons into the sub-micrometer scale, and probe its radio-efficient capabilities. SCXM, when implemented in high-energy diffraction-limited storage rings, e.g., European Synchrotron Radiation Facility Extremely Brilliant Source and PETRA IV, will open the opportunity to explore the nanoscale of unstained, unsectioned, and undamaged radiosensitive materials.

2.
Folia Biol (Praha) ; 54(1): 1-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18226358

RESUMO

Components of plant essential oils have been reported to have health benefit properties, including antioxidative, anti-tumour, antimicrobial, anti-stress, and immunomodulative activities. We examined the anti-inflammatory effects of thymoquinone, the active ingredient in the volatile oil of Nigella sativa seeds, and borneol, the active component of Salvia officinalis essential oil, on TNBS-induced colitis in mice. Thymoquinone was added to the commercial diet at a concentration of 0.05 % and borneol at two concentrations (0.09% and 0.18%) and fed to ICR mice 5 days before induction of TNBS colitis. Seven days after TNBS administration the mice were killed and macroscopic and histological scores were evaluated. Cytokine mRNA expression in colonic tissue was assessed using quantitative realtime RT-PCR. We did not detect any significant changes in macroscopic and histological scores between experimental and control groups, but we observed a significant decrease in proinflammatory cytokine (IL-1beta and IL-6) mRNA expression in colon tissue in the 0.09% and 0.18% borneol-treated groups of mice in comparison to the control group. Surprisingly, we were not able to confirm anti-inflammatory effects of thymoquinone in TNBS colitis. In conclusion, our data show that borneol is able to significantly suppress proinflammatory cytokine mRNA expression in colonic inflammation, although no significant morphological changes are visible.


Assuntos
Benzoquinonas/farmacologia , Canfanos/farmacologia , Colite/induzido quimicamente , Colite/patologia , Ácido Trinitrobenzenossulfônico/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/patologia , Citocinas/genética , Citocinas/metabolismo , DNA/metabolismo , Enzimas de Restrição do DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Physiol Res ; 56(1): 97-104, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16497088

RESUMO

Plant essential oils (EOs) have been reported to have health benefit properties and their preventive and therapeutic use in animals is expected to increase in the future. We evaluated the influence of five essential oils obtained from plant species which are known to have positive antimicrobial, antioxidative and anti-inflammatory effects--sage EO from Salvia officinalis L. (Lamiaceae), oregano EO from Origanum vulgare L. (Lamiaceae), thyme EO from Thymus vulgaris L. (Lamiaceae), clove EO from Syzygium aromaticum L. (Myrtaceae) and cinnamon EO from Cinnamomum zeylanicum Blume (Lauraceae) on the growth and development of mouse preimplantation embryos in vivo. Essential oils were added to commercial diet at concentrations of 0.25% for sage EO, thyme EO, clove EO, cinnamon EO and 0.1% for oregano EO, and fed to ICR female mice for 2 weeks ad libitum. Females were then mated with males of the same strain. Embryos obtained on Day 4 of pregnancy at the blastocyst stage were stained by morphological triple staining (Hoechst, PI, Calcein-AM) and evaluated using fluorescent microscopy. The effects of essential oils were estimated by the viability of embryos, number of nuclei and distribution of embryos according to nucleus number. Cinnamon EO significantly decreased the number of nuclei and the distribution of embryos according to nucleus number was significantly altered. Sage EO negatively influenced the distribution of embryos according to nucleus number. Clove and oregano EOs induced a significantly increased rate of cell death. Only thyme EO had no detectable effects on embryo development. In conclusion, none of the essential oils had any positive effect on embryo development, but some of them reduced the number of cells and increased the incidence of cell death.


Assuntos
Blastocisto/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cinnamomum zeylanicum , Relação Dose-Resposta a Droga , Feminino , Morte Fetal/induzido quimicamente , Morte Fetal/patologia , Marcação In Situ das Extremidades Cortadas , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Origanum , Gravidez , Salvia , Syzygium , Thymus (Planta)
4.
Struct Dyn ; 2(4): 041717, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26798816

RESUMO

A major challenge in high-resolution x-ray free-electron laser-based coherent diffractive imaging is the development of aerosol injectors that can efficiently deliver particles to the peak intensity of the focused X-ray beam. Here, we consider the use of a simple convergent-orifice nozzle for producing tightly focused beams of particles. Through optical imaging we show that 0.5 µm particles can be focused to a full-width at half maximum diameter of 4.2 µm, and we demonstrate the use of such a nozzle for injecting viruses into a micro-focused soft-X-ray FEL beam.

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