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1.
J Photochem Photobiol B ; 253: 112875, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430681

RESUMO

Candida albicans (C. albicans), a major opportunistic pathogenic fungus, is known to cause superficial skin infections. Unfortunately, the misuse of antibiotics has led to the emergence of drug resistance in fungi. Antimicrobial photodynamic therapy (aPDT), a non-antibiotic alternative, has shown potential in treating drug-resistant fungal infections. Curcumin is a photodynamically active phytochemical whose photodynamic fungicidal efficacy is largely dependent on its intracellular accumulation. However, curcumin faces challenges in penetrating the cytoplasm due to its poor water solubility and the fungal cell wall. Borneol, another monoterpenoid phytochemical, is known for its ability to enhance drug absorption. In this study, we showed that borneol improved the cellular uptake of curcumin, thereby enhancing its photodynamic fungicidal efficacy against C. albicans. This effect was attributed to borneol's ability to increase cell permeability. Transcriptomic analysis further confirmed that borneol disrupted the normal structure and function of the C. albicans cell wall and membrane, resulting in dysregulated mRNA expression of related genes and ultimately increased cell permeability. As a result, the excessive accumulation of curcumin in C. albicans triggered the overproduction of intracellular ROS upon exposure to blue light. These excessive intracellular ROS disrupted various cellular structures, interfered with essential cellular processes, inhibited biofilm formation and reduced virulence. Remarkably, borneol was also found to enhance curcumin uptake by C. albicans within biofilms, further enhancing the anti-biofilm efficacy of curcumin-mediated aPDT (Cur-aPDT). In conclusion, the results of this study strongly support the potential of borneol as an adjuvant agent to Cur-aPDT in treating superficial cutaneous fungal infections.


Assuntos
Anti-Infecciosos , Canfanos , Curcumina , Micoses , Fotoquimioterapia , Humanos , Candida albicans , Curcumina/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Fotoquimioterapia/métodos , Anti-Infecciosos/farmacologia , Adjuvantes Imunológicos/farmacologia , Compostos Fitoquímicos , Biofilmes , Fármacos Fotossensibilizantes/farmacologia
2.
Front Cardiovasc Med ; 10: 1166554, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37139135

RESUMO

Background: High visit-to-visit blood pressure variability (BPV) and hypertension are risk factors for mild cognitive impairment (MCI) and probable dementia (PD). Few articles assessed the effect of BPV on the MCI and PD in intensive blood pressure treatment and the different functions of three types of visit-to-visit BPV: systolic blood pressure variability (SBPV), diastolic blood pressure variability (DBPV) and pulse pressure variability (PPV). Methods: We performed a post hoc analysis of the SPRINT MIND trial. The primary outcomes were MCI and PD. BPV was measured by average real variability (ARV). The Kaplan-Meier curves were used to clarify the difference in tertiles of BPV. We fit Cox proportional hazards models to our outcome. We also did an interaction analysis between the intensive and standard groups. Results: We enrolled 8,346 patients in the SPRINT MIND trial. The incidence of MCI and PD in the intensive group was lower than that in the standard group. 353 patients had MCI and 101 patients had PD in the standard group while 285 patients had MCI and 75 patients had PD in the intensive group. Tertiles with higher SBPV, DBPV and PPV in the standard group had a higher risk of MCI and PD (all p < 0.05). Meanwhile, higher SBPV and PPV in the intensive group were associated with an increased risk of PD (SBPV: HR(95%) = 2.1 (1.1-3.9), p = 0.026; PPV: HR(95%) = 2.0 (1.1-3.8), p = 0.025 in model 3) and higher SBPV in the intensive group was associated with an increased risk of MCI(HR(95%) = 1.4 (1.2-1.8), p < 0.001 in model 3). The difference between intensive and standard blood pressure treatment was not statistically significant when we considered the effect of the higher BPV on the risk of MCI and PD (all p for interaction >0.05). Conclusion: In this post hoc analysis of the SPRINT MIND trial, we found that higher SBPV and PPV were associated with an increased risk of PD in the intensive group, and higher SBPV was associated with an increased risk of MCI in the intensive group. The effect of higher BPV on the risk of MCI and PD was not significantly different in intensive and standard blood pressure treatment. These findings emphasized the need for clinical work to monitor BPV in intensive blood pressure treatment.

3.
Org Biomol Chem ; 21(7): 1422-1434, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36723147

RESUMO

An investigation of asymmetric total syntheses of three indole-imidazole alkaloids from histidine are described. A common advanced piperidinone was contructed via a ring-closing metathesis which was then subjected to a modified Fischer indole synthesis. Deprotection of an N-tosyl group via a dissolving metal reduction affords haploscleridamine which upon reaction with aqueous formaldehyde in trifluoroethanol provided villagorgin A. On closer examination, it was found that villagorgin A was produced as a byproduct during the reductive detosylation in the presence of magnesium and methanol. Attempts to obtain the brominated haploscleridamine congener, lissoclin C through use of bromophenyl hydrazone were thwarted by reductive debromination during deprotection efforts. Investigation of the enantiopurity of the synthetic natural products revealed production of almost racemic materials in some batches as the result of partial racemization of an early stage intermediate. A revised approach routinely provided scalemic haploscleridamine and villagorgin in 30% ee. Analysis of the enantiomer composition of all intermediates by HPLC using columns with chiral stationary phases; this analysis revealed several steps where erosion of enantiomer composition occurred.

4.
Microbiol Spectr ; 10(5): e0169622, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36194139

RESUMO

Phytochemicals are promising antibacterials for the development of novel antibiofilm drugs, but their antibiofilm activity in physiologically relevant model systems is poorly characterized. As the host microenvironment can interfere with the activity of the phytochemicals, mimicking the complex environment found in biofilm associated infections is essential to predict the clinical potential of novel phytochemical-based antimicrobials. In the present study, we examined the antibiofilm activity of borneol, citral, and combinations of both as well as their Pickering emulsions against Staphylococcus aureus and Pseudomonas aeruginosa in an in vivo-like synthetic cystic fibrosis medium (SCFM2) model, an in vitro wound model (consisting of an artificial dermis and blood components at physiological levels), and an in vivo Galleria mellonella model. The Pickering emulsions demonstrated an enhanced biofilm inhibitory activity compared to both citral and the borneol/citral combination, reducing the minimum biofilm inhibitory concentration (MBIC) values up to 2 to 4 times against P. aeruginosa PAO1 and 2 to 8 times against S. aureus P8-AE1 in SCMF2. In addition, citral, the combination borneol/citral, and their Pickering emulsions can completely eliminate the established biofilm of S. aureus P8-AE1. The effectiveness of Pickering emulsions was also demonstrated in the wound model with a reduction of up to 4.8 log units in biofilm formation by S. aureus Mu50. Furthermore, citral and Pickering emulsions exhibited a significant degree of protection against S. aureus infection in the G. mellonella model. The present findings reveal the potential of citral- or borneol/citral-based Pickering emulsions as a type of alternative antibiofilm candidate to control pathogenicity in chronic infection. IMPORTANCE There is clearly an urgent need for novel formulations with antimicrobial and antibiofilm activity, but while there are plenty of studies investigating them using simple in vitro systems, there is a lack of studies in which (combinations of) phytochemicals are evaluated in relevant models that closely resemble the in vivo situation. Here, we examined the antibiofilm activity of borneol, citral, and their combination as well as Pickering emulsions (stabilized by solid particles) of these compounds. Activity was tested against Staphylococcus aureus and Pseudomonas aeruginosa in in vitro models mimicking cystic fibrosis sputum and wounds as well as in an in vivo Galleria mellonella model. The Pickering emulsions showed drastically increased antibiofilm activity compared to that of the compounds as such in both in vitro models and protected G. mellonella larvae from S. aureus-induced killing. Our data show that Pickering emulsions from phytochemicals are potentially useful for treating specific biofilm-related chronic infections.


Assuntos
Anti-Infecciosos , Fibrose Cística , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Pseudomonas aeruginosa/fisiologia , Emulsões , Infecção Persistente , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Biofilmes , Antibacterianos/farmacologia , Compostos Fitoquímicos
5.
RSC Adv ; 12(16): 10005-10013, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35424930

RESUMO

Antimicrobial photodynamic therapy (aPDT) is a highly attractive therapy due to its advantages of being a non-antibiotic procedure for reducing drug-resistant microbes. Curcumin (CCM) has been considered as a natural photosensitizer for PDT with prominent antibacterial, antifungal, and anti-proliferative activity. However, its excellent biological and pharmacological activities are limited because of its low solubility, rapid metabolization and instability. Herein, we reported a promising agent based on CCM-incorporated into zeolitic imidazolate framework-8 (ZIF@CCM). The as-prepared nanoparticle exhibited high drug loading capability (11.57%) and drug loading encapsulation (82.76%). Additionally, ZIF@CCM displayed a pH-responsive drug release behavior and chemophotodynamic therapy for excellent antibacterial activity. The underlying mechanism elucidated that Zn2+ released from ZIF-8 increased the permeability of the bacterial cell membrane with leakages of K+. The overproduction of extracellular ROS further resulted in the disrupted bacterial cell membrane and distorted bacterial morphology. Thus, ZIF@CCM-mediated photodynamic activation might be a promising treatment strategy for microbial inactivation.

6.
ACS Nano ; 16(3): 4379-4396, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35175721

RESUMO

Bismuth telluride (Bi2Te3) is an available thermoelectric material with the lowest band gap among bismuth chalcogenides, revealing a broad application in photocatalysis. Unfortunately, its size and morphology related to a radio-catalysis property have rarely been explored. Herein, an ethylenediaminetetraacetic acid (EDTA)-assisted hydrothermal strategy was introduced to synthesize polytypic Bi2Te3 nanoplates (BT NPs) that exhibit size-dependent radio-sensitization and metabolism characteristics in vivo. By simply varying the molar ratio of EDTA/Bi3+ during the reaction, BT NPs with different sizes and morphologies were obtained. EDTA acting as chelating agent and "capping" agent contributed to the homogeneous growth of BT NPs by eliminating dangling bonds and reducing the surface energy of different facets. Further analyzing the size-dependent radio-sensitization mechanism, larger-sized BT NPs generated holes that preferentially catalyzed the conversion of OH- to ·OH when irradiated with X-rays, while the smaller-sized BT NPs exhibited faster decay kinetics producing higher 1O2 levels to enhance radiotherapy effects. A metabolomic analysis revealed that larger-sized BT NPs were oxidized into Bi(Ox) in the liver via a citrate cycle pathway, whereas smaller-sized BT NPs accumulated in the kidney and were excreted in urine in the form of ions by regulating the metabolism of glutamate. In a cervical cancer model, BT NPs combined with X-ray irradiation significantly antagonized tumor suppression through the promotion of apoptosis in tumor cells. Consequently, in addition to providing a prospect of BT NPs as an efficient radio-sensitizer to boost the tumor radiosensitivity, we put forth a strategy that can be universally applied in synthesizing metal chalcogenides for catalysis-promoted radiotherapy.


Assuntos
Bismuto , Neoplasias , Bismuto/química , Ácido Edético , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Tolerância a Radiação , Telúrio/química
7.
Front Big Data ; 2: 41, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33693364

RESUMO

Citation analysis is one of the most commonly used methods in academic assessments. Up to now, most of academic assessments are based on English literature, ignoring the fact that the role of Chinese papers in academic assessments has become increasingly indispensable. Therefore, to give full play to the role of Chinese literature in academic assessments is an urgent task of current academic circle. Based on Chinese academic data from ScholarSpace, i.e., 82826 Chinese computer science journal papers, we conduct a comprehensive assessment of academic influence from the perspectives of fields, journals and institutions, in order to achieve a better understanding of the development of Chinese computer literature in the past 60 years. We find that Chinese scholars tend to cite papers in English, discover evolution trend of fields, journals and institutions, and call on journals, institutions, and scholars to strengthen their cooperation.

8.
ACS Appl Mater Interfaces ; 11(1): 1699-1705, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30563323

RESUMO

Laser-induced graphene (LIG) has both good electrical conductivity and three-dimensional porous structures. Here, porous graphene interdigital electrodes (IDE) were constructed as a capacitive sensor from commercial polymer films by the laser ablation process and transferred to the polydimethylsiloxane (PDMS) substrate. The graphene oxide (GO) adsorption layer was electrosprayed as a humidity sensing structure, and a Peltier device was used to control the temperature to produce the condensation of water vapors. The dew point was identified by the equilibrium state of the capacitor when the adsorption layer and the surface air reached the saturation equilibrium. The performances of the hydrophilic dew point sensing system under different environmental conditions were investigated. The results show that the precision of the carbon-based dew point sensor of ≤±0.8 °C DP with good stability and repeatability is better than those of other dew point instrument based on electrical sensing parameters at ±1.0 °C DP.

9.
Molecules ; 23(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30309003

RESUMO

Bladder cancer has become the most common malignant urinary carcinoma. Studies have shown that significant antioxidant and bladder cancer-fighting properties of several plant-based diets like Psidium guajava, ginger and amomum, are associated with their high kaempferol content. In this paper, we evaluated the antioxidant and anticancer activities of kaempferol and its mechanism of induction to apoptosis on bladder cancer cells. Our findings demonstrated that kaempferol showed an obvious radical scavenging activity in erythrocytes damaged by oxygen. Kaempferol promoted antioxidant enzymes, inhibited ROS generation and lipid peroxidation and finally prevented the occurrence of hemolysis. Additionally, kaempferol exhibited a strong inhibitory effect on bladder cancer cells and high safety on normal bladder cells. At the molecular level, kaempferol suppressed EJ bladder cancer cell proliferation by inhibiting the function of phosphorylated AKT (p-AKT), CyclinD1, CDK4, Bid, Mcl-1 and Bcl-xL, and promoting p-BRCA1, p-ATM, p53, p21, p38, Bax and Bid expression, and finally triggering apoptosis and S phase arrest. We found that Kaempferol exhibited strong anti-oxidant activity on erythrocyte and inhibitory effects on the growth of cancerous bladder cells through inducing apoptosis and S phase arrest. These findings suggested that kaempferol might be regarded as a bioactive food ingredient to prevent oxidative damage and treat bladder cancer.


Assuntos
Apoptose/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Quempferóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias da Bexiga Urinária/patologia , Amidinas/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/ultraestrutura , Humanos , Quempferóis/química , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Fase S/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
10.
J Agric Food Chem ; 66(35): 9219-9230, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30102527

RESUMO

15,16-Dihydrotanshinone I (DI), a natural compound isolated from a traditional Asian functional food Salvia Miltiorrhiza Bunge, is known for its anticancer activity. However, poor solubility of DI limits its desirable anticancer application. Herein, polylactic- co-glycolic acid (PLGA) was functionalized with polyethylene glycol (PEG) and biotin to form copolymers PEG-PLGA (PPA) and biotin-PEG-PLGA (BPA). DI was encapsulated in copolymers PPA and BPA to obtain DI-PPA-NPs (NPs = nanoparticles) and DI-BPA-NPs, respectively. The particle size and its distribution, encapsulation efficiency, and in vitro releasing capacity of DI-BPA-NPs were characterized by biophysical methods. MTT assay was used to evaluate the antiproliferative activity of free DI, DI-PPA-NPs, and DI-BPA-NPs in human cervical cancer Hela cells. DI-BPA-NPs showed the highest cytotoxicity on Hela cells with an IC50 value of 4.55 ± 0.631 µM, while it was 8.20 ± 0.849 and 6.14 ± 0.312 µM for DI and DI-PPA-NPs in 72 h, respectively. The superior antiproliferative activity was supported by the fact that DI-BPA-NPs could be preferentially internalized by Hela cells, owing to their specific interaction between biotin and overexpressed biotin receptors. In addition, DI-BPA-NPs effectively inhibited Hela cell proliferation by inducing G2/M phase cycle arrest and decreasing the intracellular reactive oxygen species (ROS) level by 31.50 ± 2.29% in 5 min. In summary, DI-BPA-NPs shows improved antiproliferative activity against human cervical cancer as comparing with free DI, demonstrating its application potential in cancer therapy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Fenantrenos/química , Fenantrenos/farmacologia , Salvia miltiorrhiza/química , Neoplasias do Colo do Útero/tratamento farmacológico , Biotina/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Feminino , Furanos , Glicolatos/química , Células HeLa , Humanos , Tamanho da Partícula , Poliésteres/química , Quinonas , Espécies Reativas de Oxigênio/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/fisiopatologia
11.
Rev Sci Instrum ; 89(6): 066107, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29960542

RESUMO

Each quartz crystal resonator (QCR) shows different frequency behavior as a function of temperature. To get the curve of the temperature effect compensation during the dew-deposition process, we use the active controlled temperature type of the QCR dew point sensor. In this note, a QCR temperature-frequency calibration method based on spectral analysis is described. It combines FFT and spectral refinement and the parameter table method to achieve high precision frequency extraction. Frequency identification accuracy is 10-6. The results showed that the method has a good performance in frequency extraction of the QCR sensors.

12.
Bone ; 114: 235-245, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29929042

RESUMO

During deep-space exploration missions, astronauts will be exposed to abnormal space environments including microgravity and hypomagnetic field (HyMF) that is 10,000 times weaker than geomagnetic field (GMF). It is well known that microgravity in space can induce bone loss; however, it is ill-defined whether HyMF involved in this process. Herein, we aimed to investigate the combined effects of HyMF and microgravity on bone loss. A mouse model of hindlimb suspension (HLU) was adopted to simulate microgravity-induced bone loss, that was exposed to a hypomagnetic field of <300 nanotesla (nT) generated by a geomagnetic field-shielding chamber. Besides, a recent study showed that HLU induced bone loss was orchestrated by iron overload. Therefore, the changes of iron content in unloading-induced bone loss under HyMF condition were detected simultaneously. The results showed HyMF exacerbated the loss of bone mineral content (BMC), induced more detrimental effects on microstructure of cancellous bone but not cortical bone and yielded greater negative effects on biomechanical characteristics in mice femur under unloading status. Concomitantly, there was more iron accumulation in serum, liver, spleen and bone in the combined treatment group than in the separate unloading group or HyMF exposure group. These results showed that HyMF promoted additional bone loss in mice femur during mechanical unloading, and the potential mechanism may be involved in inducing iron overload of mice.


Assuntos
Reabsorção Óssea/diagnóstico por imagem , Elevação dos Membros Posteriores/efeitos adversos , Sobrecarga de Ferro/diagnóstico por imagem , Campos Magnéticos/efeitos adversos , Animais , Reabsorção Óssea/etiologia , Reabsorção Óssea/metabolismo , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Suporte de Carga/fisiologia
13.
Biofactors ; 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29740891

RESUMO

The previous studies have shown that tea polyphenols are metabolized by gut microbiota. This study investigated the effect of gut microbiota on the bioavailability, tissue levels, and degradation of tea polyphenols. Mice were treated with antibiotics (ampicillin/sulfamethoxazole/trimethoprim) in drinking water and the control mice received water for 11 days, and they were given an AIN93M diet enriched with 0.32% of Polyphenon E. The levels of catechins and their metabolites (if present) in the serum, liver, urine, and fecal samples were determined by high-performance liquid chromatography. The results showed that treatment with antibiotics significantly increased the levels of the major polyphenol, (-)-epigallocatechin-3-gallate (EGCG), in serum and liver samples. Antibiotics also raised the levels of some catechins in urine and fecal samples but decreased the levels of their metabolites. These results suggest that antibiotics eliminated gut microbes and increased the bioavailabilities of these tea catechins. In a second study, mice were given different concentrations of green tea infusions as the drinking fluid. The plasma levels of EGCG and (-)-epicatechin-3-gallate (ECG) at day 112 were significantly lower than those at day 5. The urine levels of EGCG and ECG increased in the first 4 or 5 days, and then decreased to much lower levels at day 23 and beyond. In contrast, the levels of (-)-epigallocatechin and (-)-epicatechin showed a trend of increase during the 112-day experiment, likely owing to microbial hydrolysis of EGCG and ECG. Both sets of experiments support the idea that the degradation of EGCG and ECG by gut microbiota decreases their bioavailabilities. © 2018 BioFactors, 2018.

14.
Electromagn Biol Med ; 37(2): 76-83, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617158

RESUMO

All the living organisms originate, evolve and live under geomagnetic field (GMF, 20-70 µT). With rapid development in science and technology, exposure to various static magnetic fields (SMFs) from natural and man-made sources remains a public environmental topic in consideration of its probable health risk for humans. Many animal studies related to health effect have demonstrated that SMF could improve bone formation and enhance bone healing. Moreover, most of the studies focused on local SMF generated by rod-type magnet. It was difficult to come to a conclusion that how SMF affected bone metabolism in mice. The present study employed hypomagnetic field (HyMF, 500 nT), and moderate SMF (MMF, 0.2 T) to systematically investigate the effects of SMF with continuous exposure on microstructure and mechanical properties of bone. Our results clearly indicated that 4-week MMF exposure did not affect bone biomechanical properties or bone microarchitecture, while HyMF significantly inhibited the growth of mice and elasticity of bone. Furthermore, mineral elements might mediate the biological effect of SMF.


Assuntos
Fêmur/citologia , Fêmur/fisiologia , Campos Magnéticos , Fenômenos Mecânicos , Tíbia/citologia , Tíbia/fisiologia , Animais , Fenômenos Biomecânicos , Peso Corporal , Densidade Óssea , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
J Food Sci ; 83(5): 1436-1443, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29660811

RESUMO

Paclitaxel (PTX) has been used in a variety of malignancies for inhibiting tumor development and improving survival. However, its clinical application is limited due to poor solubility, drug resistance, and gastrointestinal reactions. Natural borneol (NB), as a promoter, could help to improve drug absorption. Therefore, the aims of the present study were to investigate the ability of NB to synergize with PTX to induce human esophageal squamous cell carcinoma (ESCC) cells apoptosis and the underlying mechanism of synergistic effects. In this study, our findings showed that NB could effectively synergize with PTX to inhibit the survival of ESCC cells by inducing apoptosis. The molecular mechanism by western blotting elucidated that combination treatment with PTX and NB significantly activated apoptotic pathway by triggering upregulation of cleaved caspase-3 expression and downregulation of survivin and P-AKT expression. These results demonstrated that NB could strongly potentiate PTX-induced apoptosis in ESCC cells through suppressing PI3K/AKT pathway. Thus, the combination therapy with NB and PTX might be a promising treatment strategy for human esophageal cancer. PRACTICAL APPLICATION: Esophageal cancer is one of the most common cancers in the world. It has brought about a major public health problem. Many natural agents have been employed in the synergized treatments of esophageal cancer. This study provides a comprehensive way to investigate the ability of borneol to synergize with paclitaxel to induce human esophageal squamous cell carcinoma cells apoptosis and the underlying mechanism of synergistic effects. The research showed that the combination treatment with some natural agents might be a promising treatment strategy for human esophageal cancer.


Assuntos
Apoptose/efeitos dos fármacos , Canfanos/farmacologia , Paclitaxel/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago , Humanos , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores
16.
Rev Sci Instrum ; 89(1): 014704, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29390713

RESUMO

Real-time and accurate measurements of intermediate frequency signals based on microprocessors are difficult due to the computational complexity and limited time constraints. In this paper, a fast and precise methodology based on the sigma-delta modulator is designed and implemented by first generating the twiddle factors using the designed recursive scheme. This scheme requires zero times of multiplications and only half amounts of addition operations by using the discrete Fourier transform (DFT) and the combination of the Rife algorithm and Fourier coefficient interpolation as compared with conventional methods such as DFT and Fast Fourier Transform. Experimentally, when the sampling frequency is 10 MHz, the real-time frequency measurements with intermediate frequency and narrowband signals have a measurement mean squared error of ±2.4 Hz. Furthermore, a single measurement of the whole system only requires approximately 0.3 s to achieve fast iteration, high precision, and less calculation time.

17.
Electromagn Biol Med ; 37(1): 23-34, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29235883

RESUMO

Nitric oxide (NO) is involved in osteoclast differentiation. Our previous studies showed that static magnetic fields (SMFs) could affect osteoclast differentiation. The inhibitory effects of 16 T of high SMF (HiMF) on osteoclast differentiation was correlated with increased production of NO. We raised the hypothesis that NO mediated the regulatory role of SMFs on osteoclast formation. In this study, 500 nT of hypomagnetic field (HyMF), 0.2 T of moderate SMF (MMF) and 16 T of high SMF (HiMF) were utilized as SMF treatment. Under 16 T, osteoclast formation was markedly decreased with enhanced NO synthase (NOS) activity, thus producing a high level of NO. When treated with NOS inhibitor N-Nitro-L-Arginine Methyl Ester (L-NAME), NO production could be inhibited, and osteoclast formation was restored to control group level in a concentration-dependent manner. However, 500 nT and 0.2 T increased osteoclast formation with decreased NOS activity and NO production. When treated with NOS substrate L-Arginine (L-Arg) or NO donor sodium nitroprusside (SNP), the NO level in the culture medium was obviously elevated, thus inhibiting osteoclast differentiation in a concentration-dependent manner under 500 nT or 0.2 T. Therefore, these findings indicate that NO mediates the regulatory role of SMF on osteoclast formation.


Assuntos
Campos Magnéticos , Óxido Nítrico/metabolismo , Osteoclastos/citologia , Osteoclastos/metabolismo , Animais , Arginina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Nitroprussiato/farmacologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/enzimologia , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
Rev Sci Instrum ; 88(5): 056103, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28571406

RESUMO

A new sensor with dual-channel was designed for eliminating the temperature effect on the frequency measurement of the quartz crystal microbalance (QCM) in dew point detection. The sensor uses active temperature control, produces condensation on the surface of QCM, and then detects the dew point. Both the single-channel and the dual-channel methods were conducted based on the device. The measurement error of the single-channel method was less than 0.5 °C at the dew point range of -2 °C-10 °C while the dual-channel was 0.3 °C. The results showed that the dual-channel method was able to eliminate the temperature effect and yield better measurement accuracy.

19.
Biotechnol Lett ; 39(9): 1351-1358, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28573541

RESUMO

OBJECTIVES: To investigate the roles of miR-215 in high-grade glioma and to clarify the regulation of retinoblastoma 1 (RB1) by miR-215. RESULTS: miR-215 is frequently up-regulated in high-grade glioma tissues. Increased miR-215 expression is significantly associated with World Health Organization grade (P < 0.01) tumor size (P < 0.05) and poor prognosis (P < 0.01). Over-expression of miR-215 promoted cell proliferation and knockdown of miR-215 inhibited cell proliferation in vitro. RB1 was identified as a direct and functional target of miR-215. RB1 is generally down-regulated in glioma tissues and its expression inversely correlated with miR-215, which is up-regulated in high-grade glioma tissues, and its expression was negatively correlated with miR-215. CONCLUSIONS: The new miR-215/RB1 axis provides new insights into the molecular mechanism and treatment for glioma.


Assuntos
Glioma/patologia , Glioma/fisiopatologia , MicroRNAs/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Expressão Gênica , Perfilação da Expressão Gênica , Humanos
20.
Rev Sci Instrum ; 88(1): 015005, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28147650

RESUMO

A fast dew point sensor has been developed for organic vapor mixtures by using the quartz crystal with sensitive circuits. The sensor consists of the quartz crystal and a cooler device. Proactive approach is taken to produce condensation on the surface of the quartz crystal, and it will lead to a change in electrical features of the quartz crystal. The cessation of oscillation was measured because this phenomenon is caused by dew condensation. Such a phenomenon can be used to detect the dew point. This method exploits the high sensitivity of the quartz crystal but without frequency measurement and also retains the stability of the resonant circuit. It is strongly anti-interfered. Its performance was evaluated with acetone-methanol mixtures under different pressures. The results were compared with the dew points predicted from the universal quasi-chemical equation to evaluate the performance of the proposed sensor. Though the maximum deviations of the sensor are less than 1.1 °C, it still has a fast response time with a recovery time of less than 10 s, providing an excellent dehumidifying performance.

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