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1.
Mol Nutr Food Res ; 67(24): e2300330, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37880898

RESUMO

SCOPE: Cellular senescence (CS) is closely related to tissue ageing including bone ageing. CS and the senescence-associated secretory phenotype (SASP) have emerged as critical pathogenesis elements of senile osteoporosis. This study aims to investigate the effect of lycopene on senile osteoporosis. METHODS AND RESULTS: The senescence-accelerated mouse prone 6 (SAMP6) strain of mice is used as the senile osteoporosis model. Daily ingestion of lycopene for 8 weeks preserves the bone mass, density, strength, and microarchitecture in the SAMP6 mice. Moreover, these alterations are associated with a decrease in oxidative stress in the senile osteoporosis model. In addition, there is a reduction in osteoblast and osteocyte senescence and the SASP in the bone tissues of the SAMP6 mice. Lycopene improves bone health likely due to its antioxidant properties that may be linked with the regulation of CS and SASP in the SAMP6 mice. CONCLUSION: These results suggest that lycopene may be beneficial for the management of senile osteoporosis by inhibiting oxidative stress, CS, and the SASP.


Assuntos
Osso e Ossos , Osteoporose , Camundongos , Animais , Licopeno/farmacologia , Modelos Animais de Doenças , Osteoporose/tratamento farmacológico , Senescência Celular , Estresse Oxidativo
2.
Sci Total Environ ; 883: 163507, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37059139

RESUMO

Increasing crop yields to ensure food security while also reducing agriculture's environmental impacts to ensure green sustainable development are great challenges for global agriculture. Plastic film, widely used to improve crop yield, also creates plastic film residue pollution and greenhouse gas emissions that restricts the development of sustainable agriculture. So, one of those challenges is to reduce plastic film use while also ensuring food security, and thus promote green and sustainable development. A field experiment was conducted during 2017-2020 at 3 farmland areas, each with different altitudes and climate conditions, in northern Xinjiang, China. We investigated the effects on maize yield, economic returns, and greenhouse gas (GHG) emissions of plastic film mulching (PFM) versus no mulching (NM) methods in drip-irrigated maize production. We also chose maize hybrids with 3 different maturation times and used 2 planting densities to further investigate how those differences more specifically affect maize yield, economic returns, and greenhouse gas (GHG) emissions under each mulching method. We found that by using maize varieties with a utilization rate of accumulated temperature (URAT) <86.6 % with NM, and increasing the planting density by 3 plants m-2, yields and economic returns improved and GHG emissions reduced by 33.1 %, compared to those of PFM maize. The maize varieties with URATs between 88.2 % to 89.2 %, had the lowest GHG emissions. We discovered that by matching the required accumulated temperatures of various maize varieties to environmental accumulated temperatures, along with filmless and higher density planting, and modern irrigation and fertilization practices, yields increased and residual plastic film pollution and carbon emissions reduced. Therefore, these advances in agronomic management are important steps toward reducing pollution and achieving carbon peak and carbon neutrality goals.


Assuntos
Gases de Efeito Estufa , Zea mays , Carbono , Solo/química , Gases de Efeito Estufa/análise , Plásticos , Agricultura/métodos , Segurança Alimentar , China , Fertilizantes
3.
Food Funct ; 13(22): 11770-11779, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36285709

RESUMO

Radiation therapy (RT) is a crucial part of many treatment plans for cancer patients. However, major undesired side effects are associated with this treatment, including impaired bone remodeling and bone loss. Irradiation induces bone loss due to promoted osteoclastic bone resorption and reduced osteoblastic bone formation. Astaxanthin (AST) is a natural antioxidant with anti-oxidative and anti-aging properties. However, it is unclear whether AST is also protective against osteoporosis induced by ionizing radiation (IR). Here, we evaluate the efficacy of AST in mitigating IR-induced bone loss in a mouse model where both hindlimbs received radiation. Reduced BMD, bone biomechanical strength, bone formation, elevated oxidative stress, and osteoclast activity with microarchitectural deterioration of trabecular and cortical bones were observed in IR mice. Supplementation with AST corrected these osteoporotic phenotypes, caused by IR, by inhibiting oxidative stress, DNA damage, osteocyte senescence, and senescence-associated secretory phenotype (SASP), subsequently promoting osteoblastic bone formation and inhibiting osteoclastic bone resorption. The results from our study provide experimental evidence for the clinical use of AST to prevent IR-induced osteoporosis in cancer patients.


Assuntos
Antioxidantes , Reabsorção Óssea , Osteoporose , Animais , Camundongos , Reabsorção Óssea/tratamento farmacológico , Senescência Celular , Osteócitos , Osteoporose/prevenção & controle , Estresse Oxidativo
4.
Sci Rep ; 11(1): 24053, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34912019

RESUMO

Nitrocellulose (NC) is widely used in both military and civilian fields. Because of its high chemical sensitivity and low decomposition temperature, NC is prone to spontaneous combustion. Due to the dangerous properties of NC, it is often dissolved in other organic solvents, then stored and transported in the form of a solution. Therefore, this paper took NC solutions (NC-S) with different concentrations as research objects. Under different atmospheric conditions, a series of thermal analysis experiments and different reaction kinetic methods investigated the influence of solution concentration and oxygen concentration on NC-S's thermal stability. The variation rules of NC-S's thermodynamic parameters with solution and oxygen concentrations were explored. On this basis, the spontaneous combustion characteristics of NC-S under actual industrial conditions were summarized to put forward the theoretical guidance for the spontaneous combustion treatment together with the safety in production, transportation, and storage.

5.
Biofabrication ; 12(4): 045009, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650321

RESUMO

Blood vessel narrowing and arterial occlusion are pathological hallmarks of atherosclerosis, which involves a complex interplay of perturbed hemodynamics, endothelial dysfunction and inflammatory cascade. Herein, we report a novel circular microfluidic stenosis model that recapitulates atherogenic flow-mediated endothelial dysfunction and blood-endothelial cell (EC) interactions in vitro. 2D and 3D stenosis microchannels with different constriction geometries were fabricated using 3D printing to study flow disturbances under varying severity of occlusion and wall shear stresses (100 to 2000 dynecm-2). Experimental and fluid simulation results confirmed the presence of pathological shear stresses in the stenosis region, and recirculation flow post stenosis. The resultant pathological flow profile induced pro-inflammatory and pro-thrombotic EC state as demonstrated by orthogonal EC alignment, enhanced platelet adhesion at the stenosis, and aberrant leukocyte-EC interactions post stenosis. Clinical utility of the vascular model was further investigated by testing anti-thrombotic and immunomodulatory efficacy of aspirin and metformin, respectively. Overall, the platform enables multi-factorial analysis of critical atherogenic events including endothelial dysfunction, platelets and leukocyte adhesion, and can be further developed into a liquid biopsy tool for cardiovascular risk stratification.


Assuntos
Aterosclerose/patologia , Aterosclerose/fisiopatologia , Vasos Sanguíneos/patologia , Hemorreologia , Imageamento Tridimensional , Inflamação/fisiopatologia , Modelos Cardiovasculares , Perfusão , Vasos Sanguíneos/fisiopatologia , Constrição Patológica , Monitoramento de Medicamentos , Células Endoteliais/patologia , Fatores Imunológicos/farmacologia , Inflamação/patologia , Fenótipo , Trombose/patologia , Engenharia Tecidual
6.
Am J Transl Res ; 12(3): 743-757, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32269709

RESUMO

An increased fracture risk is often observed in cancer patients undergoing radiotherapy (RT), particularly at sites within the field of radiation. Therefore, the development of appropriate therapeutic options to prevent RT-induced bone loss is urgently needed. A soluble form of the BMP receptor type 1A fusion protein (mBMPR1A-mFc) serves as an antagonist to endogenous BMPR1A. Previous studies have shown that mBMPR1A-mFc treatment increases bone mass in both ovary-intact and ovariectomized via promoting osteoblastic bone formation and inhibiting osteoclastic bone resorption. The present study was designed to investigate whether mBMPR1A-mFc administration prevents radiation-induced bone deterioration in mice. We constructed an animal model of radiation-induced osteoporosis by exposure to a 2-Gy dose of X-rays. Micro-CT, histomorphometric, bone-turnover, and mechanical analyses showed that mBMPR1A-mFc administration prevented trabecular microarchitecture deterioration after RT because of a marked increase in bone formation and a decrease in bone resorption. Mechanistic studies indicated that mBMPR1A-mFc administration promoted osteoblastogenesis by activating Wnt/Lrp5/ß-catenin signaling while decreasing osteoclastogenesis by inhibiting the RANKL/RANK/OPG pathway. Our novel findings provide solid evidence for the application of mBMPR1A-mFc as a therapeutic treatment for radiation-induced osteoporosis.

7.
Am J Transl Res ; 11(7): 4232-4247, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396331

RESUMO

Glucocorticoid-induced osteoporosis (GIOP) is a frequent complication of systemic glucocorticoid (GC) therapy, is the most common form of secondary osteoporosis, and is associated with skeletal fragility and increased fracture risk. A soluble form of BMP receptor type 1A fusion protein (mBMPR1A-mFc) acts as an antagonist to endogenous BMPR1A and could increase bone mass in both ovariectomized and ovary-intact mice, but its effects in GIOP mice remained unclear. The aim of this study was to evaluate the effects of mBMPR1A-mFc on the skeleton in experimental models of GIOP. mBMPR1A-mFc treatment could increase the bone mineral density (BMD), trabecular bone volume, thickness, and number, and cortical thickness, and reduce the structure model index and trabecular separation in GIOP mice. mBMPR1A-mFc treatment could also prevent bone loss and enhance biomechanical strength in GIOP mice by promoting osteoblastic bone formation and inhibiting osteoclastic bone resorption. Mechanistic studies revealed that mBMPR1A-mFc treatment increased murine osteoblastogenesis by activating the Wnt/ß-catenin signaling pathway while decreasing osteoclastogenesis by inhibiting the RANK/RANKL/osteoprotegerin (OPG) signaling pathway. These findings demonstrate that mBMPR1A-mFc treatment in GIOP mice improves bone mass, microarchitecture, and strength by enhancing osteoblastic bone formation and inhibiting osteoclastic bone resorption in GIOP mice and offers a promising novel alternative for the treatment of GIOP.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1235-9, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30052354

RESUMO

X-ray tube is the most commonly used equipment in X-ray fluorescence spectrum analysis as excitation source whose primary spectrum has become a major source of the background of X-ray fluorescence spectrum. Background subtraction should go before further analysis of this spectrum. The accuracy of the estimation of the background directly affect the results of subsequent processing steps. In this paper, the tube excitation component of X fluorescence spectrum is analyzed with an estimation method of background intensity against their background characteristics, and structuring theoretical spectral lines based on the measured spectral lines in order to evaluate the effect of spectral processing algorithms. The method utilizes the measured X-ray fluorescence spectrum which does not contain the characteristic peak of the spectrum, In order to estimate the composition of the original spectrum of the X-ray tube. It uses the spectrum that contains the continuous background for interpolating the entire measured spectrum, thereby avoiding overlapping the spectral characteristic peaks or improperly estimating full width at half maximum. This paper compared SNIP, Fourier transform method and the background subtraction method using the measured spectral lines. Using this method to estimate the background is closer to the theoretical background. The results showe that the method for X-ray fluorescence spectrum by X-ray tube excitation is accurate in this article, this method can be used to deduct continuous background, and good applied effectiveness has been achieved in the background subtraction of the actually measured X-ray fluorescence spectrometry.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1240-4, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30052355

RESUMO

This paper proposes the analyzing method of adopting wavelength dispersive X-ray fluorescence spectrometry to measure the content of Cu and Zn in PM2.5. PTFE membrane is used to prepare standard samples and atmospheric particulate samples; a research into sample cup's structure,using polypropylene film of 6.7 µm to help to improved sample cup to package atmospheric particulate samples. The improved sample cup is used to measure the content of Cu and Zn in atmospheric particulate, which can obviously reduce background, improve peak/background ratio and decrease detection limit to target element; discussion is made on the measurement condition of Cu and Zn in PM2.5: taking Kα line as analysis line of Cu and Zn, selecting PX10 as analyzer crystal, using 300 µm pitch collimator, adopting scintillation detector for the Kα of Zn, applying the integrating of flow-gas proportional counter and closed-end proportional counter to the Kα of Cu, setting 50 kV, 50 mA as operating voltage and current. The prepared Cu and Zn standard sample is used to set up working curve, the results show that their linear correlations are better, accuracy are higher, relative standard deviations of Cu and Zn are 2.43% and 2.00%(n=8), detection limit are 0.028 and 0.021 µg·cm-2respectively, and analysis of the single sample only need 60 s. To sum up, this method can quickly and accurately analyze the content of Cu and Zn in PM2.5, and provide scientific basis for study the element content characteristics and source apportionment.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 2043-8, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26717776

RESUMO

N, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba and Pb in herb tea were determined by X-ray fluorescence spectrometry with pressed powder pellets. The measuring conditions of target elements were investigated, including how to select its analytical line. In addition to Ba and Pb using L line, Kalpha line was selected for the rest. When the Compton scattered radiation of Rh Kalpha was measured, The X-ray tube voltage should be appropriately reduced, and the appropriate tube current should be selected. The matrix effect was corrected by empirical coefficient method and using scattered radiation (the Rayleigh scattered radiation of Rh Lalpha, the scattered background of 0.1876 nm wavelength position and the Compton scattered radiation of Rh Kalpha) as internal standard, and the spectral overlapping interference of some elements (N, Na, Ca, Ti, Mn, Sr and Ba) was corrected. For the target elements, the detection limit of this method was low, and its accuracy and precision were high. The results showed that there were abandon of elements in herb tea, of which different kinds had different components, even the same kind of herb tea with different source had some difference in element and content more or less, however, there was a lot of similarity between the features of its components. In a word, this method could achieve multi-element determination of herb tea, and it was simple in operation, low cost, rapid, and accurate.


Assuntos
Espectrometria de Fluorescência , Chás de Ervas/análise , Oligoelementos/análise
11.
Zhongguo Zhong Yao Za Zhi ; 38(13): 2082-5, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24079230

RESUMO

OBJECTIVE: To investigate the effect of plant growth regulators on the growth and quality of Angelica dahurica var. formosana. METHOD: Five plant growth regulators: chlormequat chloride (CCC), Mepiquat chloride (PIX), Gibberellic acid (GA3), Paclobutrazol (PP333) and Maleic Hydrazide (MH) were sprayed in rosette stage, the effects of these plant growth regulators (PGRs) on the growth, yield and quality of A. dahurica var. formosanaw were observed. The biological traits were first measured and then imperatorin and isoimperatorin contents in roots were determined by HPLC. RESULT: Low concentration GA3 increased the yield while not influenced the premature bolting rate and the coumarin content. CONCLUSION: Spraying of GA3 (30 mg x L(-1)) could guarantee the growth and development of A. dahurica var. formosana to have a higher yield and maintain the active ingredients content in the root as well.


Assuntos
Angelica/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/farmacologia , Angelica/efeitos dos fármacos , Clormequat/farmacologia , Giberelinas/farmacologia , Hidrazida Maleica/farmacologia , Piperidinas/farmacologia , Triazóis/farmacologia
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2242-5, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24159885

RESUMO

The present paper discusses the influence of matrix effect on measurement results when portable energy dispersive X-ray fluorescence analyzer is used for the determination of Ni in soil. Based on the scattered X-ray intensity of WL(alpha) emitted from the X-ray tube on the sample, a correction method was proposed, and it combines with the correction of absorption element, which can effectively overcome the matrix effect. The correlation coefficient of the content prediction model based on this method is 0.999 and the residual standard deviation is 2.541. The average relative error is 3.90 when the content prediction model is used to measure the content of Ni in the national standard soil samples, so the results coincide well with standard values, and the precision is high.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 383-5, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22512173

RESUMO

Raman spectroscopy was used to study the influence of ultraviolet-A(UV-A) radiation on collagen I. The Raman spectra of collagen I and that after 90 min UV-A radiation were reported. The results proved that irradiation with 90 min UV-A caused the change in the structures of collagen I. Intramolecular hydrogen bonds were broken, and the hydrogen bonding system was changed. The intensity of helix was decreased, while the intensity of the disordered conformation in proteins such as random coil was increased. Otherwise, the UV-A radiation influenced the hydroxylation of proline and the content of hydroxyproline was reduced. The changes caused by UV-A radiation could damage the triple helical structure of collagen I. It would lead to a series of changes, such as the destruction of collagen fibers during the photoaging of skin.


Assuntos
Colágeno , Raios Ultravioleta , Ligação de Hidrogênio , Hidroxilação , Prolina , Estrutura Secundária de Proteína , Proteínas , Análise Espectral Raman
14.
Phys Med Biol ; 55(20): 6175-85, 2010 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-20876971

RESUMO

Ultraviolet B (UVB) has been widely used in dermatological phototherapy. Narrowband UVB (NB-UVB), with a peak at 311 nm, is considered to be more effective than broadband UVB (BB-UVB). However, the safety of NB-UVB is controversial. In this study, we first introduced optical coherence tomography (OCT), a novel, non-invasive in vivo imaging technology, to assess the effect of NB-UVB and BB-UVB on skin. Balb/c mice dorsal skin was exposed with increasing UVB doses (1MED, 3MEDs and 5MEDs), and then OCT images of the tissues were obtained by an OCT system with 1310 nm central wavelength. Quantitative parameters (skin thickness, disruption of the entrance signal and correlation coefficient) were extracted from the OCT images. The data indicated that NB-UVB-induced skin lesions were similar to that of BB-UVB at 1MED or 3MEDs UVB. However, the skin tissues exposed with 5MEDs NB-UVB suffered from more lesions than BB-UVB. Furthermore, the persistence of skin inflammation in 3MEDs NB-UVB-induced skin tissues was much longer than that of BB-UVB (P = 0.004). In conclusion, optimized treatment time and frequency as well as close clinical monitoring should be undertaken to reduce the latent risk of NB-UVB phototherapy.


Assuntos
Pele/patologia , Pele/efeitos da radiação , Tomografia de Coerência Óptica/métodos , Raios Ultravioleta/efeitos adversos , Animais , Relação Dose-Resposta à Radiação , Feminino , Inflamação/diagnóstico , Inflamação/etiologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos BALB C , Pele/citologia
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