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1.
Small ; 19(11): e2205825, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36587982

RESUMO

The combination of photodynamic therapy (PDT) and chemotherapy (chemo-photodynamic therapy) for enhancing cancer therapeutic efficiency has attracted tremendous attention in the recent years. However, limitations, such as low local concentration, non-suitable treatment light source, and uncontrollable release of therapeutic agents, result in reduced combined treatment efficacy. This study considered adenosine triphosphate (ATP), which is highly upregulated in tumor cells, as a biomarker and developed ingenious ATP-activated nanoparticles (CDNPs) that are directly self-assembled from near-infrared photosensitizer (Cy-I) and amphiphilic Cd(II) complex (DPA-Cd). After selective entry into tumor cells, the positively charged CDNPs would escape from lysosomes and be disintegrated by the high ATP concentration in the cytoplasm. The released Cy-I is capable of producing single oxygen (1 O2 ) for PDT with 808 nm irradiation and DPA-Cd can concurrently function for chemotherapy. Irradiation with 808 nm light can lead to tumor ablation in tumor-bearing mice after intravenous injection of CDNPs. This carrier-free nanoparticle offers a new platform for chemo-photodynamic therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Camundongos , Cádmio , Fármacos Fotossensibilizantes/uso terapêutico , Raios Infravermelhos , Neoplasias/tratamento farmacológico
2.
Langmuir ; 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36623173

RESUMO

The application of graphitic carbon nitride (g-C3N4) in photocatalytic NO oxidation was limited due to severe recombination of photogenerated carriers and low concentration of oxidizing species. In this work, K and B were introduced into the interlayer and in-plane framework of g-C3N4 to address this challenge through the thermal polymerization process. The synthesized K-doped B-g-C3N4 nanosheets exhibited expanded light absorption and low charge recombination efficiency. In addition, the doping of K and B reduced the band gap of g-C3N4, which corresponded to enhanced light absorption. B was introduced into the in-plane structure by replacing C atoms, which adjusted the in-plane electron distribution. K was inserted into the interlayer by binding to the N and C atoms of adjacent layers. K-derived electron transfer channels were constructed, which increased electron delocalization and expanded the π-conjugate system. More electrons were transferred through the interlayer channels and were involved in the reaction process. The severe carrier recombination and weak transfer were improved due to the synergistic effect of K and B doping. K-doped B-g-C3N4 nanosheets exhibited enhanced generation of superoxide radicals and hydroxyl radicals, which played a key role during NO oxidation. The photocatalytic NO oxidation efficiency of codoped g-C3N4 nanosheets reached 61%, which was 2.1 and 1.2 times of that of pristine g-C3N4 and B-doped g-C3N4, respectively. The codoped g-C3N4 sample still exhibited stable photocatalytic NO oxidation efficiency after five cycles. This result provided a potential idea for improving the charge distribution and transfer of layered materials by codoping metallic and nonmetallic elements and for photocatalytic NO oxidation.

3.
Environ Monit Assess ; 195(12): 1428, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938430

RESUMO

Coal and grain complex areas influence the geochemical characterization of REEs through coal mining activities and agricultural production. However, there is a lack of relevant studies. In this study, we investigated the geochemical characterization and risk assessment of REEs in river sediments of the northern Anhui plain, a typical coal-grain composite area. The results showed that the average concentrations of ∑REE in the sediments ranged from 134.7 to 220.3 µg/g, and LREE was significantly enriched. Among the 14 REEs, Gd and Eu were the most enriched, with enrichment factors of 1.792 and 1.764, respectively. In addition, the differences in REEs content and enrichment between different rivers were related to the location of coal mines and the degree of population concentration. The average values of δCe and δEu in the sediments were 0.990 and 1.080, respectively, and most of the sampling sites showed a weak positive Ce, Eu anomaly. The results of Pearson's correlation and RDA redundancy analyses showed that Fe, Al, Mn and sand contributed more to the enrichment of REEs. The river sediments in the whole area had a slight potential ecological risk, with Eu (Er=13.05) and Lu (Er=14.07) having the highest potential risk. The ADD results also showed that the average daily dose of REEs by children was around 2.000 (µg/(kg·day)), which was significantly higher than that of adults. The results of this study can be used as a basis for the prevention and control of REEs in rivers in northern Anhui Province.


Assuntos
Metais Terras Raras , Rios , Adulto , Criança , Humanos , Monitoramento Ambiental , China , Carvão Mineral , Grão Comestível
4.
Angew Chem Int Ed Engl ; 62(44): e202308761, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37496129

RESUMO

Enzymatic reactions can consume endogenous nutrients of tumors and produce cytotoxic species and are therefore promising tools for treating malignant tumors. Inspired by nature where enzymes are compartmentalized in membranes to achieve high reaction efficiency and separate biological processes with the environment, we develop liposomal nanoreactors that can perform enzymatic cascade reactions in the aqueous nanoconfinement of liposomes. The nanoreactors effectively inhibited tumor growth in vivo by consuming tumor nutrients (glucose and oxygen) and producing highly cytotoxic hydroxyl radicals (⋅OH). Co-compartmentalization of glucose oxidase (GOx) and horseradish peroxidase (HRP) in liposomes could increase local concentration of the intermediate product hydrogen peroxide (H2 O2 ) as well as the acidity due to the generation of gluconic acid by GOx. Both H2 O2 and acidity accelerate the second-step reaction by HRP, hence improving the overall efficiency of the cascade reaction. The biomimetic compartmentalization of enzymatic tandem reactions in biocompatible liposomes provides a promising direction for developing catalytic nanomedicines in antitumor therapy.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Lipossomos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Glucose Oxidase/farmacologia , Peroxidase do Rábano Silvestre , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanotecnologia , Peróxido de Hidrogênio/uso terapêutico
5.
Langmuir ; 38(33): 10225-10233, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35939646

RESUMO

AuCu alloy nanoparticles (NPs) were embedded in superior thin g-C3N4 nanosheets by a mechanochemical pre-reaction and subsequent thermal polymerization at high temperature. The introduction of AuCu NPs increased conductivity, decreased the band gap, expended light absorption, and improved the separation and transfer efficiencies of photogenerated electrons and holes. Moreover, the uniform distribution of AuCu NPs in g-C3N4 nanosheets is ascribed to the pre-reaction of bulk g-C3N4 and metal salts to create activity cites. The adsorption ability in the visible light region was improved due to the plasma effect of Au. AuCu/g-C3N4 composites (AuCu/CN-1%) with optimized component ratios revealed the highest transient photocurrent responses, the lowest electrochemical impedance arc radius, and the best photocatalytic H2 evolution rate of 930.2 µmol g-1 h-1. These findings exhibited that loading AuCu bimetallic NPs could efficiently offset some disadvantages of g-C3N4 and improve its photocatalytic performances.

6.
Environ Res ; 213: 113504, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35640709

RESUMO

The humic substances (HS) - mediated electron transfer process is of great significance to the reduction and degradation of pollutants and the improvement of soil quality. Different soil conditions lead to different characteristics of HS, resulting in differences in the electron transfer capacity (ETC) of HS. It is unclear how the environmental conditions in soil affect the ETC by affecting on HS. In this study, the response relationship of soil microenvironment, HS and ETC has been studied. The results show that the ETC follows the descending order of: Langshan > Nanchang > Anqing > Beijing > Guilin. There were significant differences in ETC in soil HS in different regions. There were significant differences in electron-donating capacity (EDC) in soil HS in different regions and depths. EDC in soil was higher than electron-accepting capacity (EAC), and on average, are 22.4 times higher than the EAC. The HS components of soils in different regions are different. The most significant differences were in tyrosine-like substances and soluble microbial by-products (SMPs). The five components of the soil HS from Langshan were the most different from those in other regions. There were differences in SMPs and humic-like substances in soils of different depths in Anqing and Guilin. ETC can be affected by the composition of HS components in different regions. The composition of HS at different soil depths in the same regions had little effect on ETC. SMPs can promote ETC and EDC, and tyrosine-like substance can promote EDC. Moisture content, pH and TOC are the main factors affecting the composition of HS components. This results can provide a research basis for the sustainable and safe utilization of agricultural soil.


Assuntos
Substâncias Húmicas , Solo , Agricultura , Elétrons , Substâncias Húmicas/análise , Solo/química , Tirosina
7.
J Xray Sci Technol ; 30(1): 145-163, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34897109

RESUMO

In this paper, we present an arc based fan-beam computed tomography (CT) reconstruction algorithm by applying Katsevich's helical CT image reconstruction formula to 2D fan-beam CT scanning data. Specifically, we propose a new weighting function to deal with the redundant data. Our weighting function ϖ(x_,λ) is an average of two characteristic functions, where each characteristic function indicates whether the projection data of the scanning angle contributes to the intensity of the pixel x_. In fact, for every pixel x_, our method uses the projection data of two scanning angle intervals to reconstruct its intensity, where one interval contains the starting angle and another contains the end angle. Each interval corresponds to a characteristic function. By extending the fan-beam algorithm to the circle cone-beam geometry, we also obtain a new circle cone-beam CT reconstruction algorithm. To verify the effectiveness of our method, the simulated experiments are performed for 2D fan-beam geometry with straight line detectors and 3D circle cone-beam geometry with flat-plan detectors, where the simulated sinograms are generated by the open-source software "ASTRA toolbox." We compare our method with the other existing algorithms. Our experimental results show that our new method yields the lowest root-mean-square-error (RMSE) and the highest structural-similarity (SSIM) for both reconstructed 2D and 3D fan-beam CT images.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Tomografia Computadorizada por Raios X , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada por Raios X/métodos
8.
Anal Chem ; 93(40): 13539-13547, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34581571

RESUMO

Monitoring the tumor oxygen level when implementing photodynamic therapy (PDT) on malignant cancer has vital significance but remains challenging yet. Herein, by structurally manipulating a 2,4-dimethylpyrrole-engineered asymmetric BODIPY scaffold with different kinds, numbers, and positions of halogen atoms, we rationally designed several monochromophore-based bifunctional photosensitizers, named BDPs (BDP-I, BDP-II, and BDP-III), with self-sensitized photooxidation characteristics for accurate oxygen reporting and photodynamic tumor ablation. We show that different ways of halogen regulation allow available tuning of BDPs' oxygen-dependent ratiometric fluorescence turn-ons upon light irradiation as well as type-II PDT efficiencies before and after self-sensitized photooxidation. Encouragingly, measuring the specific ratiometric signals of the most promising BDP-II enabled the direct observation of initial oxygen concentration in both living 4T1 cells and a tumor-bearing mice model, affording an alternative way for evaluating oxygen supplementation strategies. Meanwhile, the "always on" PDT effect of BDP-II ensured efficient tumor ablation via apoptosis. Our research was thus believed to be of instructive significance for future application of oxygen-related auxiliary strategies and the design of unimolecular multifunctional PDT agents for cancer precision therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Animais , Linhagem Celular Tumoral , Camundongos , Neoplasias/tratamento farmacológico , Oxigênio , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
9.
Ecotoxicol Environ Saf ; 214: 112084, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33640726

RESUMO

Direct Black G (DBG) is a highly toxic synthetic azo dye which is difficult to degrade. Biological treatment seems to be a promising option for the treatment of azo dye containing effluent. A thermophilic bacterial strain (Anoxybacillus sp. PDR2) previously isolated from the soil can effectively remove DBG. However, the molecular underpinnings of DBG degradation and the microbial detoxification ability remains unknown. In the present study, the genetic background of PDR2 for the efficient degradation of DBG and its adaptation to azo dye-contaminated environments was revealed by bioinformatics. Moreover, the possible biodegradation pathways were speculated based on the UV-vis spectral analysis, FTIR, and intermediates identified by LC-MS. Additionally, phytotoxicity and the comet experiment studies clearly indicated that PDR2 converts toxic azo dye (DBG) into low toxicity metabolites. The combination of biodegradation pathways and detoxification analysis were utilized to explore the molecular degradation mechanism and bioremediation of azo dye for future applications. These findings will provide a valuable theoretical basis for the practical treatment of azo dye wastewater.


Assuntos
Anoxybacillus/metabolismo , Compostos Azo/metabolismo , Biodegradação Ambiental , Anoxybacillus/genética , Bactérias/metabolismo , Cor , Corantes/metabolismo , Humanos , Solo , Águas Residuárias
10.
J Acoust Soc Am ; 149(6): 3929, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34241423

RESUMO

The time-varying multipath introduces major distortions to transmissions in the underwater acoustic communication channel. Channel estimation is often used as one of the central steps to address such distortions in high-rate communication receivers. The focus of this paper is to quantify the impacts of the channel fluctuations on the performance of the least-squares channel estimator. A metric, channel variation ratio (CVR), is defined to describe the rate of fluctuations in the channel impulse responses. Equations are derived to reveal the direct relationships between the CVR and channel estimation performance, which is measured by the channel estimation mean squared error (MSE) and signal prediction error (SPE). The equations show that both the MSE and SPE increase linearly with the CVR. The MSE and SPE metrics both have an error floor for time-varying impulse responses, even with zero ambient noise. It is confirmed that an optimum estimated channel length, achieving the minimum estimation error, exists for time-varying impulse responses. The truncation effects in the channel estimation are also investigated. Experimental data are used to validate the findings.

11.
J Gastroenterol Hepatol ; 35(10): 1712-1719, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31945189

RESUMO

BACKGROUND AND AIM: This study aimed to investigate the postoperative quality of life (QOL) between laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) and laparoscopy-assisted distal gastrectomy with Billroth I anastomosis (LADGBI) in patients with middle-third early gastric cancers (EGC). METHODS: From January 2015 to August 2017, a total 91 patients with EGC underwent LAPPG or LADGBI procedure with complete QLQ-C30 and QLQ-STO22 in Ren Ji Hospital. Not only do surgical and oncological safety as well as clinicopathologic characteristics analyze, but also chronological changes of QOL and nutritional status were compared for the evaluation of functional advantages. RESULTS: There was no significant difference in clinicopathologic characteristics and perioperative recovery between LAPPG and LADGBI. During postoperative 2-year follow up, LAPPG showed significant advantages over LADGBI in emotional functioning, insomnia, appetite loss, reflux, and taste problem and presented larger area in global and functional scales and less area in symptom scales, which means that LAPPG tended to present better improvement and less symptoms than LADGBI for QOL 2 years after surgery. Furthermore, LAPPG could bring about significant improvement in total protein and hemoglobin compared to LADGBI at postoperative 2 years. CONCLUSION: LAPPG obtains QOL as well as total protein and hemoglobin superiority and could be recommended to patients with EGC whose tumor located in the middle third of the stomach.


Assuntos
Endoscopia Gastrointestinal/métodos , Gastrectomia/métodos , Gastroenterostomia/métodos , Laparoscopia/métodos , Tratamentos com Preservação do Órgão/métodos , Piloro/cirurgia , Neoplasias Gástricas/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Estadiamento de Neoplasias , Estado Nutricional , Qualidade de Vida , Neoplasias Gástricas/patologia , Inquéritos e Questionários , Resultado do Tratamento
12.
Ecotoxicol Environ Saf ; 203: 111047, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888598

RESUMO

Understanding azo dye degrading enzymes and the encoding of their functional genes is crucial for the elucidation of their molecular mechanisms. In this study, a thermophilic strain capable of degrading azo dye was isolated from the soil near a textile dye manufacturing factory. Based on its morphological, physiological and biochemical properties, as well as 16S rRNA gene sequence analysis, the strain was identified as Anoxybacillus sp. PDR2. The decolorization ratios of 100-600 mg/L Direct Black G (DBG) by strain PDR2 reached 82.12-98.39% within 48 h of dyes. Genome analysis revealed that strain PDR2 contains a circular chromosome of 3791144 bp with a G + C content of 42.48%. The genetic basis of azo dye degradation by strain PDR2 and its capacity to adapt to harsh environments, were further elucidated through bioinformatics analysis. RNA-Seq and qRT-PCR technology confirmed that NAD(P)H-flavin reductase, 2Fe-2S ferredoxin and NAD(P)-dependent ethanol dehydrogenase genes expressed by strain PDR2, were the key genes involved in DBG degradation. The combination of genome and transcriptome analysis was utilized to explore the key genes of strain PDR2 involved in azo dye biodegradation, with these findings providing a valuable theoretical basis for the practical treatment of azo dye wastewater.


Assuntos
Anoxybacillus/isolamento & purificação , Compostos Azo/análise , Corantes/análise , Genes Bacterianos , Microbiologia do Solo , Anoxybacillus/genética , Anoxybacillus/metabolismo , Compostos Azo/metabolismo , Biodegradação Ambiental , China , Corantes/metabolismo , Perfilação da Expressão Gênica , Genômica , RNA Ribossômico 16S/genética , Solo/química , Indústria Têxtil
13.
IEEE Trans Signal Process ; 68: 5349-5364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-35418738

RESUMO

The robust Chinese remainder theorem (CRT) has been recently proposed for robustly reconstructing a large nonnegative integer from erroneous remainders. It has found many applications in signal processing, including phase unwrapping and frequency estimation under sub-Nyquist sampling. Motivated by the applications in multidimensional (MD) signal processing, in this paper we propose the MD-CRT and robust MD-CRT for Integer vectors with respect to a general set of integer matrix moduli, which provides an algorithm to uniquely reconstruct integer vectors with respect to a general set of integer matrix moduli, which provides an algorithm to uniquely reconstruct an integer vector from its remainders, if it is in the fundamental parallelepiped of the lattice generated by a least common right multiple of all the moduli. For some special forms of moduli, we present explicit reconstruction formulae. Moreover, we derive the robust MD-CRT for integer vectors when the remaining integer matrices of all the moduli left divided by their greatest common left divisor (gcld) are pairwise commutative and coprime. Two different reconstruction algorithms are proposed, and accordingly, two different conditions on the remainder error bound for the reconstruction robustness are obtained, which are related to a quarter of the minimum distance of the lattice generated by the gcld of all the moduli or the Smith normal form of the gcld.

14.
BMC Cancer ; 19(1): 481, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117975

RESUMO

BACKGROUND: Laparoscopic-assisted pylorus-preserving gastrectomy (LAPPG) is a minimally invasive function-preserving surgery for early gastric cancer. This study was designed to investigate the clinical outcomes between LAPPG and laparoscopy-assisted distal gastrectomy (LADG) by objective evaluation. METHODS: A total 167 pT1N0M0 gastric cancer patients underwent LAPPG(n = 70) and LADG(n = 97) were retrospectively analyzed. By evaluating the functional advantages, objective short-term and one year follow-up outcomes were compared. RESULTS: There is no significant difference in perioperative clinical characteristics as well as pathologic results between LAPPG and LADG group while the cost is higher in latter(p = 0.004). The Clavien-Dindo grade II or higher complications were 15.7 and 13.4% in LAPPG and LADG group respectively(p = 0.824). In one year follow-up, nutritional status was significantly better in LAPPG group accompanied by better pylorus function preserving. CONCLUSION: LAPPG is an acceptable surgical procedure for pT1N0M0 middle portion gastric cancer patients in terms of nutritional and economic advantage. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( ChiCTR-PIC-17012358 , Date of Registration:2017-08-14).


Assuntos
Gastrectomia/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias Gástricas/cirurgia , Idoso , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estado Nutricional , Piloro , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Resultado do Tratamento
15.
Cell Biol Int ; 43(11): 1267-1275, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30839137

RESUMO

Numerous studies have demonstrated the therapeutic effect of bone mesenchymal stem cells on spinal cord injury (SCI), especially on neural stem cells (NSCs). However, the predominant mechanisms of bone mesenchymal stem cells (BMSCs) are unclear. Recently, some researchers have found that paracrine signaling plays a key role in the therapeutic capacity of BMSCs and emphasized that the protective effect of BMSCs may be due to paracrine factors. In this study, we aimed to investigate the potential mechanisms of BMSCs to protect NSCs. NSCs were identified by immunocytochemistry. The oxidative stress environment was simulated by H2 O2 (50, 100, 200 µM) for 2 h. The apoptotic rate of the NSCs was detected via flow cytometry. Lactate dehydrogenase (LDH), malondialdehyde (MDA), and superoxide dismutase (SOD) activity were evaluated via corresponding assay kits. Western blot was used to detect the expressions of Notch1, HES1, caspase-3, cleave caspase-3, Bax, and Bcl-2. We found that H2 O2 could significantly induce the apoptosis of NSCs, increase LDH, MDA levels, and decrease SOD activity by activating the Notch1 signaling pathway. DAPT (the specific blocker of Notch1) and BMSC-conditioned medium (BMSC-CM) could significantly prevent the apoptotic effect and oxidative stress injury on NSCs that were treated with H2 O2 . We also revealed that BMSC-CM could decrease the expression of Notch1, Hes1, cleave caspase-3, Bax, and increases the expression of Bcl-2 in NSCs, which was induced by H2 O2 . These results have revealed that BMSC-CM can neutralize the effect against oxidative stress injury on the apoptosis of NSCs by inhibiting the Notch1 signaling pathway.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neurais/metabolismo , Receptor Notch1/metabolismo , Animais , Células Cultivadas , Células-Tronco Mesenquimais/citologia , Camundongos , Células-Tronco Neurais/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
16.
Exp Cell Res ; 369(1): 120-128, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29772221

RESUMO

Hypoxia is a hallmark of pancreatic cancer (PC) and is associated with gemcitabine resistance. However, the mechanisms underlying hypoxia-induced gemcitabine resistance in PC remain greatly unknown. Our previous work showed that miR-301a, a hypoxia-sensitive miRNA, is involved in PC metastasis under hypoxia via regulation of its target gene P63. Here, we showed that miR-301a was upregulated in a NF-κB independent manner and promoted gemcitabine resistance under hypoxic conditions in vitro. In addition, TAp63, a member of the P63 family, reversed hypoxia-induced gemcitabine resistance by promoting degradation of HIF-1α. Furthermore, we proved that TAp63 was a functional downstream target of miR-301a and mediated the biological properties of miR-301a in PC. Taken together, these findings indicate that miR-301a exerts as a critical regulator involved in hypoxia-induced gemcitabine resistance in PC and may have potentials to be a therapeutic target for PC patients.


Assuntos
Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/fisiologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Hipóxia Tumoral/fisiologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Células Tumorais Cultivadas , Hipóxia Tumoral/efeitos dos fármacos , Hipóxia Tumoral/genética , Gencitabina
17.
Appl Opt ; 58(4): 1139-1145, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874173

RESUMO

Here, a newly designed 16×16 cyclic arrayed waveguide grating router, capable of achieving loss uniformity across the whole free spectral range (FSR), is fabricated and experimentally demonstrated. This device is based on commonly used silica waveguides, which are compatible with basic planar lightwave circuit technology. The design, simulation, and experimental verification of the proposed method are presented, with the experimental results showing that the loss non-uniformity of FSR reduced from 2.70 to 1.05 dB using this new design. This design brings in only tiny changes of mask and real estate.

18.
J Environ Sci (China) ; 80: 66-81, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952354

RESUMO

The cloud optical depth (COD) is one of the important parameters used to characterize atmospheric clouds. We analyzed the seasonal variations in the COD over East Asia in 2011 using cloud mode data from the AERONET (Aerosol Robotic Network) ground-based observational network. The applicability of the MODIS (Moderate Resolution Imaging Spectroradiometer) COD product was verified and compared with the AERONET cloud mode dataset. There was a good correlation between the AERONET and the MODIS. The spatial and temporal distribution and trends in the COD over China were then analyzed using MODIS satellite data from 2003 to 2016. The seasonal changes in the AERONET data and the time sequence variation of the satellite data suggest that the seasonal variations in the COD are significant. The result shows that the COD first decreases and then increases with the season in northern China, and reaches the maximum in summer and minimum in winter. However, the spatial distribution change is just the opposite in southern China. The spatial variation trend shows the COD in China decreases first with time and gradually increases after 2014. And the trend of COD in the western and central China is consistent with that in China. While the trend of COD shows a continuously increasing over time in northeast China and the Pearl River Delta.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Imagens de Satélites , Aerossóis , Poluição do Ar/estatística & dados numéricos , China , Material Particulado , Estações do Ano , Análise Espaço-Temporal
19.
Cell Physiol Biochem ; 49(3): 971-984, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184529

RESUMO

BACKGROUND/AIMS: Parkinson's disease (PD) is a prevalent disease that leads to motor and cognitive disabilities, and oxidative stress (OS) injury was found to be related to the etiology of PD. Increasing evidence has shown that SHC3 is aberrantly expressed in neurons. The current study examines the involvement of SHC3 silencing in OS injury in the nigral dopamine neurons in rats with PD via the PI3K-AKT-FoxO signaling pathway. METHODS: To study the mechanisms and functions of SHC3 silencing in PD at the tissue level, 170 rats were selected, and a lentivirus-based packaging system was designed to silence SHC3 expression in rats. Furthermore, PC12 cells were selected for in vitro experimentation. To evaluate the effect of SHC3 silencing in nigral dopamine neuronal growth, an MTT assay, propidium iodide (PI) single staining and Annexin V-PI double staining were performed to detect cell viability, cell cycle progression and cell apoptosis, respectively. RESULTS: SHC3 shRNA led to decreased SOD and MDA levels and enhanced GSH activity, indicating that SHC3 silencing leads to motor retardation. SHC3 silencing repressed the extent of Akt and FoxO phosphorylation, thereby inhibiting the PI3K-AKT-FoxO signaling pathway. Furthermore, in cell experiments, SHC3 silencing suppressed PC12 cell proliferation and cell cycle progression, whereas it enhanced cell apoptosis. CONCLUSION: The current study provides evidence suggesting that SHC3 silencing may aggravate OS injury in nigral dopamine neurons via downregulation of the PI3K-AKT-FoxO signaling pathway in PD rats.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Estresse Oxidativo , Transdução de Sinais , Proteína 3 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Animais , Comportamento Animal , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Lentivirus/genética , Masculino , Malondialdeído/metabolismo , Células PC12 , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína 3 de Transformação que Contém Domínio 2 de Homologia de Src/antagonistas & inibidores , Proteína 3 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Superóxido Dismutase/metabolismo
20.
Analyst ; 143(21): 5218-5224, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30270379

RESUMO

A fluorescence probe, Cz-BDP-NBD, for detecting biothiols with two photon excited fluorescence has been designed and used under irradiation from sapphire pulsed lasers at 800 nm. Upon addition of biothiols, NBD was removed through a SNAr reaction and the fluorophore Carbazyl BODIPY (Cz-BDP) was released simultaneously. A two photon excited fluorescence was turned on and accompanied by a strong red emission at 660 nm, the two-photon absorption (TPA) cross section of the Cz-BDP reached a value of 198.5 GM at 800 nm. Moreover, Hcy/Cys and GSH could be distinguished between by a two emission channel, which resulted from the different mechanisms. For Hcy and Cys, N-NBD-Hcy and N-NBD-Cys were formed through a 5/6-membered cyclic transition, they displayed distinct fluorescent turn-on signal changes at 540 nm (Φ = 0.28, Φ = 0.24) and 670 nm, while GSH only has a single emission channel at 670 nm. Therefore, the Cz-BDP-NBD can distinguish GSH, Hcy and Cys with a fast response time (within one minute), high selectivity and sensitivity. In addition, it has been successfully applied for the detection of Cys/Hcy and GSH in living cells and ratio imaging. The Cz-BDP-NBD probe could be used for discriminative sensing of intracellular Cys, Hcy and GSH, and has the potential for use in biological applications.


Assuntos
Cisteína/análise , Corantes Fluorescentes/química , Glutationa/análise , Homocisteína/análise , Compostos de Boro/síntese química , Compostos de Boro/química , Compostos de Boro/efeitos da radiação , Compostos de Boro/toxicidade , Carbazóis/síntese química , Carbazóis/química , Carbazóis/efeitos da radiação , Carbazóis/toxicidade , Cisteína/metabolismo , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Glutationa/metabolismo , Homocisteína/metabolismo , Humanos , Limite de Detecção , Células MCF-7 , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Oxidiazóis/síntese química , Oxidiazóis/química , Oxidiazóis/efeitos da radiação , Oxidiazóis/toxicidade , Fótons
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