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1.
Artigo em Inglês | MEDLINE | ID: mdl-38818580

RESUMO

Fibroblast growth factor (FGF) isoform 13, a distinct type of FGF, boasts significant potential for therapeutic intervention in cardiovascular dysfunctions. However, its impact on regulating fibrosis remains unexplored. This study aims to elucidate the role and mechanism of FGF13 on cardiac fibrosis. Here, we show that following transverse aortic constriction (TAC) surgery, interstitial fibrosis and collagen content increase in mice, along with reduced ejection fraction and fractional shortening, augmented heart mass. However, following Fgf13 deletion, interstitial fibrosis is decreased, ejection fraction and fractional shortening are increased, and heart mass is decreased, compared with those in the TAC group. Mechanistically, incubation of cardiac fibroblasts with transforming growth factor ß (TGFß) increases the expressions of types I and III collagen proteins, as well as α-smooth muscle actin (α-SMA) proteins, and enhances fibroblast proliferation and migration. In the absence of Fgf13, the expressions of these proteins are decreased, and fibroblast proliferation and migration are suppressed, compared with those in the TGFß-stimulated group. Overexpression of FGF13, but not FGF13 mutants defective in microtubule binding and stabilization, rescues the decrease in collagen and α-SMA protein and weakens the proliferation and migration function of the Fgf13 knockdown group. Furthermore, Fgf13 knockdown decreases ROCK protein expression via microtubule disruption. Collectively, cardiac Fgf13 knockdown protects the heart from fibrosis in response to haemodynamic stress by modulating microtubule stabilization and ROCK signaling pathway.

2.
Appl Opt ; 62(6): 1510-1520, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821312

RESUMO

Currently, the emission of greenhouse gases is one of humanity's leading threats. To accurately and efficiently measure greenhouse gas levels in the atmosphere, we must develop imaging spectrometer systems with larger numerical apertures (NAs). However, designing a telescope with a large NA is difficult in this system. This paper presents a design strategy for aperture expansion to create a freeform telescope with a large NA. We compared different off-axis reflective telescopes and chose the Korsch structure, which has obvious advantages because of its wide field of view (FoV), large NA, and low stray light. Moreover, based on the influence of the position of the freeform surface in the aberration correction, we propose to use a single freeform surface to reduce the cost and increase manufacturability. A freeform telescope with an effective focal length of 84 mm, a large NA of 0.25, and a wide FoV of 20° is successfully designed. The modulation transfer function of the system is better than 0.62, the maximum distortion is controlled to be less than 0.486%, and the incident angle of the beam on the image plane is less than 10°. The design result shows that the instrument has wide FoV, large NA, low stray light, and high performance. At the same time, the design strategy in this paper provides an effective method for the telescope design of the imaging spectrometer with a large NA.

3.
Appl Opt ; 61(33): 10021-10031, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606835

RESUMO

Wide-field-of-view (FoV) Offner imaging spectrometers with freeform surfaces have been studied extensively in recent years. However, a design result with a large numerical aperture (NA) cannot be simultaneously obtained with this layout. We present the concept of a limited system in the tangential direction. Based on this insight, we present a new design method, to the best of our knowledge, based on the decenter anamorphic stop, which can achieve large NA in compact wide-FoV Offner imaging spectrometers with freeform surfaces. Compared to conventional imaging spectrometers with the same parameters, the light-gathering capacity of the decenter anamorphic stop-based imaging spectrometer is increased by more than 40%. In addition, based on the presented method, we design a compact imaging spectrometer with a wide FoV and large NA. The designed imaging spectrometer with a freeform surface has excellent performance. Finally, we fabricate and measure the freeform mirror. The surface irregularity of the freeform mirror is better than 1/30λ (λ=632.8n m). The result shows that the Offner imaging spectrometer with a freeform surface can be fabricated and will play a significant role in the fields of aeronautical and astronautical remote sensing.

4.
Foodborne Pathog Dis ; 11(3): 215-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24328454

RESUMO

An exploratory study was performed to determine the influence of fast pyrolysis (FP) and slow pyrolysis (SP) biochars on enterohemorrhagic Escherichia coli O157:H7 (EHEC) in soil. Soil + EHEC (inoculated at 7 log colony-forming units [CFU]/g of soil) + 1 of 12 types of biochar (10% total weight:weight in soil) was stored at 22°C and sampled for 8 weeks. FP switchgrass and FP horse litter biochars inactivated 2.8 and 2.1 log CFU/g more EHEC than no-biochar soils by day 14. EHEC was undetectable by surface plating at weeks 4 and 5 in standard FP switchgrass, FP oak, and FP switchgrass pellet biochars. Conversely, EHEC populations in no-biochar control samples remained as high as 5.8 and 4.0 log CFU/g at weeks 4 and 5, respectively. Additionally, three more SP hardwood pellet biochars (generated at 500°C for 1 h, or 2 h, or generated at 700°C for 30 min) inactivated greater numbers of EHEC than did the no-biochar control samples during weeks 4 and 5. These results suggest that biochar can inactivate E. coli O157:H7 in cultivable soil, which might mitigate risks associated with EHEC contamination on fresh produce.


Assuntos
Carvão Vegetal/farmacologia , Escherichia coli O157/efeitos dos fármacos , Microbiologia do Solo , Animais , Contagem de Colônia Microbiana , Escherichia coli O157/crescimento & desenvolvimento , Escherichia coli O157/isolamento & purificação , Cavalos , Humanos , Panicum , Quercus , Solo , Temperatura , Madeira
5.
Biochem Pharmacol ; 225: 116329, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38821375

RESUMO

Calcium signaling abnormality in cardiomyocytes, as a key mechanism, is closely associated with developing heart failure. Fibroblast growth factor 13 (FGF13) demonstrates important regulatory roles in the heart, but its association with cardiac calcium signaling in heart failure remains unknown. This study aimed to investigate the role and mechanism of FGF13 on calcium mishandling in heart failure. Mice underwent transaortic constriction to establish a heart failure model, which showed decreased ejection fraction, fractional shortening, and contractility. FGF13 deficiency alleviated cardiac dysfunction. Heart failure reduces calcium transients in cardiomyocytes, which were alleviated by FGF13 deficiency. Meanwhile, FGF13 deficiency restored decreased Cav1.2 and Serca2α expression and activity in heart failure. Furthermore, FGF13 interacted with microtubules in the heart, and FGF13 deficiency inhibited the increase of microtubule stability during heart failure. Finally, in isoproterenol-stimulated FGF13 knockdown neonatal rat ventricular myocytes (NRVMs), wildtype FGF13 overexpression, but not FGF13 mutant, which lost the binding site of microtubules, promoted calcium transient abnormality aggravation and Cav1.2 downregulation compared with FGF13 knockdown group. Generally, FGF13 deficiency improves abnormal calcium signaling by inhibiting the increased microtubule stability in heart failure, indicating the important role of FGF13 in cardiac calcium homeostasis and providing new avenues for heart failure prevention and treatment.


Assuntos
Sinalização do Cálcio , Fatores de Crescimento de Fibroblastos , Insuficiência Cardíaca , Microtúbulos , Miócitos Cardíacos , Animais , Masculino , Camundongos , Ratos , Células Cultivadas , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microtúbulos/metabolismo , Microtúbulos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Ratos Sprague-Dawley
6.
J Environ Manage ; 118: 196-204, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-23454371

RESUMO

In this work, the surface structures of biochars, derived from three types of biomass, switchgrass (SG), hardwood (HW) and softwood (SW) through either fast pyrolysis (FP) in a fluidized-bed reactor (at 500 °C) or slow pyrolysis (at 500° and 700 °C), were studied in detail, and compared with that of the activated carbons obtained by steam activation of the slow pyrolyzed biochars (at 500 °C). The surface acidic functional groups were determined quantitatively by the Boehm Titration method. The adsorptive properties of heavy metals, Zn(2+) and Cu(2+) onto the biochars and the activated carbons were investigated by the adsorption isotherms and SEM images, and correlated with the surface properties. ATR-FTIR and GC techniques were used to analyze the adsorptive behavior of phenol onto the biochars and activated carbons, and the results demonstrated that phenol adsorption capability is directly proportional to the micropore surface area as well as the combined level of the accessible carboxylic and lactonic groups. The relative adsorption capacity with respect to the biomass precursor follows the order: SW > HW > SG.


Assuntos
Carvão Vegetal/química , Cobre/química , Panicum/química , Fenol/química , Madeira/química , Zinco/química , Adsorção , Biomassa , Incineração , Microscopia Eletrônica de Varredura , Porosidade , Especificidade da Espécie , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura
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