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1.
CNS Neurosci Ther ; 30(7): e14831, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961317

RESUMO

AIMS: Comorbid anxiodepressive-like symptoms (CADS) in chronic pain are closely related to the overactivation of the lateral habenula (LHb). Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels have been implicated to play a key role in regulating neuronal excitability. However, the role of HCN channels in the LHb during CADS has not yet been characterized. This study aimed to investigate the effect of HCN channels in the LHb on CADS during chronic pain. METHODS: After chronic neuropathic pain induction by spared nerve injury (SNI), mice underwent a sucrose preference test, forced swimming test, tail suspension test, open-field test, and elevated plus maze test to evaluate their anxiodepressive-like behaviors. Electrophysiological recordings, immunohistochemistry, Western blotting, pharmacological experiments, and virus knockdown strategies were used to investigate the underlying mechanisms. RESULTS: Evident anxiodepressive-like behaviors were observed 6w after the SNI surgery, accompanied by increased neuronal excitability, enhanced HCN channel function, and increased expression of HCN2 isoforms in the LHb. Either pharmacological inhibition or virus knockdown of HCN2 channels significantly reduced LHb neuronal excitability and ameliorated both pain and depressive-like behaviors. CONCLUSION: Our results indicated that the LHb neurons were hyperactive under CADS in chronic pain, and this hyperactivation possibly resulted from the enhanced function of HCN channels and up-regulation of HCN2 isoforms.


Assuntos
Depressão , Habenula , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Animais , Habenula/metabolismo , Habenula/efeitos dos fármacos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Camundongos , Masculino , Depressão/metabolismo , Neuralgia/metabolismo , Neuralgia/psicologia , Camundongos Endogâmicos C57BL , Dor Crônica/metabolismo , Dor Crônica/psicologia , Canais de Potássio
2.
Exp Ther Med ; 26(5): 511, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37840564

RESUMO

[This retracts the article DOI: 10.3892/etm.2016.3176.].

3.
Langmuir ; 39(36): 12599-12609, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37643352

RESUMO

In this study, a 2D structured triaminoguanidine-glyoxal polymer with a high nitrogen content has been coordinated with metal ions to produce energetic metal complexes (TAGP-Ms) employed as energetic burn rate inhibitors. The metal ions (Ba2+, K+, and Ca2+) are elaborately selected based on their ability of suppressing the burn rate of composite propellants. The CL-20 crystals were intercalated with prepared TAGP-Ms materials via a solvent-antisolvent method for realization of the precise control on burning behaviors of studied propellants. The influence of TAGP-Ms inhibitors on thermal decomposition and combustion characteristics of high-energy composite propellants was evaluated using thermal analysis and a combustion diagnostic method. Results of TGA/DSC-FTIR measurements suggest that the thermal decomposition of CL-20-containing composite propellants was found to be constrained by varied degrees as a result of TAGP-Ms additions, in which the TAGP-K displays a stronger effect on suppressing the thermal decomposition of CL-20 compared with that of other TAGP-Ms. The FTIR spectra indicate that the primary gaseous phase products are composed of N2O, H2O, and CO2 in CL-20 decomposition, as well as by HCl, H2O, NO2, and N2O in the decomposition of AP for all studied composite propellants. The combustion characterizations show that the TAGP-K-containing composite propellant exhibits a significantly reduced rate of heat release but is associated with a higher flame radiation intensity increased by 4.2% compared with that of the reference propellant, which clearly implies that the TAGP-K is capable of suppressing the energy release rate while ensuring the high energetic features of propellants to be well maintained. Moreover, the burn rate pressure exponents are considerably decreased by ∼10% for the TAGP-K-containing propellants in comparison with those of propellants with the typical formulation, which strongly suggests that TGAP-Ms are promising candidates for tuning the combustion behaviors of composite propellants by influencing the decomposition processes of CL-20 and AP collectively.

4.
Langmuir ; 39(21): 7503-7513, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37186958

RESUMO

In this paper, the two-dimensional (2D) high nitrogen triaminoguanidine-glyoxal polymer (TAGP) has been used to dope hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) crystals using a microfluidic crystallization method. A series of constraint TAGP-doped RDX crystals using a microfluidic mixer (so-called controlled qy-RDX) with higher bulk density and better thermal stability have been obtained as a result of the granulometric gradation. The crystal structure and thermal reactivity properties of qy-RDX are largely affected by the mixing speed of the solvent and antisolvent. In particular, the bulk density of qy-RDX could be slightly changed in the range from 1.78 to 1.85 g cm-3 as a result of varied mixing states. The obtained qy-RDX crystals have better thermal stability than pristine RDX, showing a higher exothermic peak temperature and an endothermic peak temperature with a higher heat release. Ea for thermal decomposition of controlled qy-RDX is 105.3 kJ mol-1, which is 20 kJ mol-1 lower than that of pure RDX. The controlled qy-RDX samples with lower Ea followed the random 2D nucleation and nucleus growth (A2) model, whereas controlled qy-RDX with higher Ea (122.8 and 122.7 kJ mol-1) following some complex model between A2 and the random chain scission (L2) model.

5.
Environ Sci Pollut Res Int ; 29(49): 74163-74172, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35633458

RESUMO

Semi-coking wastewater contains a rich source of toxic and refractory compounds. Three-dimensional electro-Fenton (3D/EF) process used CuFe2O4 as heterocatalyst and activated carbon (AC) as particle electrode was constructed for degrading semi-coking wastewater greenly and efficiently. CuFe2O4 nanoparticles were prepared by coprecipitation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy disperse spectroscopy (EDS). Factors like dosage of CuFe2O4, applied voltage, dosage of AC and pH, which effect COD removal rate of semi-coking waste water were studied. The results showed that COD removal rate reached to 80.9% by 3D/EF process at the optimum condition: 4 V, 0.3 g of CuFe2O4, 1 g of AC and pH = 3. Trapping experiment suggesting that hydroxyl radical (•OH) is the main active radical. The surface composition and chemical states of the fresh and used CuFe2O4 were analyzed by XPS indicating that Fe, Cu, and O species are involved into the 3D/EF process. Additionally, anode oxidation and the adsorption and catalysis of AC are also contributed to the bleaching of semi-coking waste water. The possible mechanisms of 3D/EF for degrading semi-coking waste water by CuFe2O4 heterocatalyst were proposed.


Assuntos
Coque , Poluentes Químicos da Água , Catálise , Carvão Vegetal/química , Coque/análise , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Oxirredução , Águas Residuárias/química , Poluentes Químicos da Água/análise
6.
Bioorg Med Chem Lett ; 32: 127719, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33253878

RESUMO

The extraction, purification, structure and hepatoprotective activity of a homogenous polysaccharide (SPS60) from Sabia parviflora were investigated. SPS60 was screened after purification with Sephadex G-100 and showed the excellent hepatoprotective activity. Its structural characteristics were investigated by Time of flight mass spectrometry (TOF-MS), PMP Pre-column derivatization-HPLC (PMP-HPLC), nuclear magnetic resonance (NMR) spectroscopy and Atomic Force Microscopy (AFM). The results showed that SPS60 possessed the molecular weight of 16900 Da and the monosaccharide component was glucose, as well as a 1 â†’ 6 glycosidic bond. The results of atomic force microscopy (AFM) show that SPS60 is a blocky sphere in solution. Furthermore, the SPS60 could significantly improve the survival rate of LO2 hepatocytes which were damaged by CCl4. Therefore, SPS60 may be an active substance of S. parviflora as a local functional tea.


Assuntos
Magnoliopsida/metabolismo , Polissacarídeos/química , Substâncias Protetoras/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Folhas de Planta/metabolismo , Caules de Planta/metabolismo , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia
7.
J Hazard Mater ; 398: 122842, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768811

RESUMO

In this paper, the widely used energetic material RDX had been modified with 2D high nitrogen polymer (TAGP). Various hybrid RDX crystals (qy-RDX) with higher detonation velocity and better thermostability had been obtained as a result of strong intermolecular interactions between TAGP and RDX molecules. The performance of the qy-RDX had been characterized to clarify the inherent mechanisms. It shows that the⊿Hf of qy-RDX could be largely changed in the range of 23.4 kJ kg-1 to 1343.6 kJ kg-1, whereas the density varies only from 1.81 g cm-3 to 1.86 g cm-3. The resulted detonation velocities are in the range of 8725.5 m·s-1 to 9251.8 m·s-1, depending on the content and state of the TAGP dopant. The sensitivity of the resulted qy-RDX is much better than pristine RDX due to improved crystal quality as well as higher concentration of hydrogen bonds. The impact energy is improved from 8.5 J (RDX) to 22 J (qy-RDX-1), whereas the friction sensitivity improves form 130 N to over 360 N for the same case. The Ea for thermal decomposition of qy-RDX-1has reduced from 147.8 kJ mol-1 (RDX) to (124.5 kJ mol-1), since TAGP dopant could be considered as active catalytic sites after melting of RDX.

8.
Nanomaterials (Basel) ; 9(5)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137752

RESUMO

A quantitative evaluation method has been developed to study the effects of nanoadditives on thermal decomposition mechanisms of energetic compounds using the conventional thermogravimetry coupled with mass spectrometry (TG/MS) technique. The decomposition of ammonium perchlorate (AP) under the effect of several energetic catalysts has been investigated as a demonstration. In particular, these catalysts are transition metal (Cu2+, Co2+ and Ni2+) complexes of triaminoguanidine (TAG), using graphene oxide (GO) as dopant. They have been well-compared in terms of their catalytic effects on the concentration of the released gaseous products of AP. These detailed quantitative analyses of the gaseous products of AP provide a proof that the proton transfer between O and O2 determines the catalytic decomposition pathways, which largely depend on the type of reactive centers of the catalysts. This quantitative method could be applied to evaluate the catalytic effects of any other additives on the thermal decomposition of various energetic compounds.

9.
Fitoterapia ; 127: 349-355, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29621599

RESUMO

Five new guaiane-type sesquiterpene lactones, caroguaianolide A-E (1-5), along with nine known sesquiterpene lactones (6-14) were isolated from the whole plant of Carpesium abrotanoides L. Their structures were elucidated on the basis of spectroscopic date, HRESIMS analysis, and comparison of experimental and calculated ECD data. All isolated compounds (1-14) were tested in vitro for their cytotoxic activities against the MDA-MB-231, HGC-27 cancer cell lines, of which compounds 1-3, 6, 7, 11 and 12 showed significant cytotoxic activities with IC50 values ranging from 2.67 to 12.34 µM.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Asteraceae/química , Lactonas/isolamento & purificação , Sesquiterpenos de Guaiano/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lactonas/farmacologia , Estrutura Molecular , Sesquiterpenos de Guaiano/farmacologia
10.
Exp Ther Med ; 11(6): 2349-2354, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27284319

RESUMO

The present study aimed to investigate the role of microRNA (miR)-210 in the development of intervertebral disc degeneration (IDD). Human nucleus pulposus (NP) samples were collected from patients with scoliosis and IDD (n=12 each) as the scoliosis control and IDD groups, respectively. The expression levels of miR-210 were detected using reverse-transcription quantitative polymerase chain reaction. In vitro overexpression and knockdown of miR-210 in human NP cells were achieved by transfection of NP cells with lentiviral pre-miR-210 and antagomiR-210, respectively. The protein expression levels of homeobox A9 (HOXA9) were then detected in NP cells with modulated miR-210 using western blot analysis. Flow cytometry with allophycocyanin-Annexin V/7 and 7-aminoactinomycin D staining was also used to detect the proportion of NP cells with modulated miR-210 undergoing apoptosis. The current study revealed that the miR-210 expression was decreased in patients with IDD compared with that of the scoliosis control group (P<0.05). Furthermore, the upregulation of miR-210 with pre-miR-210 led to the repression of HOXA9. The HOXA9 level was significantly lower in these cells compared with that of NP cells treated with a corresponding negative sequence (P<0.05). Knockdown of miR-210 with antagomiR-210 resulted in upregulation of HOXA9 in NP cells, determined as the level of HOXA9 was significantly higher than that of NP cells treated with a negative sequence (P<0.05). The proportion of apoptotic NP cells also significantly decreased following treatment with pre-miR-210 compared with the scoliosis control group (12.1±1.43 vs. 23.8±1.22%, respectively; P<0.05). In conclusion, downregulation of miR-210 may promote Fas-mediated apoptosis in human IDD by regulating the expression of HOXA9. This indicates that miR-210 may be closely associated with the development of IDD and may act as a novel target in IDD treatment.

11.
Medicine (Baltimore) ; 95(25): e3953, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27336892

RESUMO

This study aimed to determine the therapeutic effect of radiofrequency combined with low-dose collagenase injected into the disc interior via an anterior cervical approach for cervical intervertebral disc herniation.Forty-three patients (26-62-year old; male/female ratio: 31/12) with cervical intervertebral disc herniation received radiofrequency combined with 60 to 100 U of collagenase, injected via an anterior cervical approach. The degree of nerve function was assessed using the current Japanese Orthopaedic Association (JOA) scoring system at 3 and 12 months postoperation. A visual analogue scale (VAS) was used to evaluate the degree of pain preoperation and 7 days postoperation. The preoperative and 3 month postoperative protrusion areas were measured and compared via magnetic resonance imaging (MRI) and picture archiving and communication systems (PACS).Compared with the preoperative pain scores, the 7-day postoperative pain was significantly reduced (P <0.01). The excellent and good rates of nerve function amelioration were 93.0% and 90.7% at 3 and 12 months postoperation, respectively, which was not significantly different. Twenty-seven cases exhibited a significantly reduced protrusion area (P <0.01) at 3 months postoperation. No serious side effects were noted.To our knowledge, this is the first study to demonstrate that the use of radiofrequency combined with low-dose collagenase injection into the disc interior via an anterior cervical approach is effective and safe for the treatment of cervical intervertebral disc herniation.


Assuntos
Ablação por Cateter/métodos , Vértebras Cervicais , Colagenases/administração & dosagem , Deslocamento do Disco Intervertebral/terapia , Adulto , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Injeções , Deslocamento do Disco Intervertebral/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Mol Med Rep ; 12(3): 3909-3915, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26016719

RESUMO

Spinal cord injury (SCI)­induced osteoporosis may cause mild trauma to bone and increase the risk of bone fracture. The present study aimed to investigate the efficacy of coenzyme Q (CoQ10) on SCI­induced osteoporosis in rats. SCI was induced by surgical transection of the cord at the T10­12 level. Animals were treated with CoQ10 (10 mg/kg; intragastrically) daily from 12 h after the surgery and over 10 subsequent days. At the end of the experimental period, blood was collected from the animals and femurs and tibiae were removed for evaluation using biochemical assays. Treatment with CoQ10 prevented SCI­induced bone loss by rescuing the decreased levels of bone mineral density and bone mineral content observed in the SCI rats. Furthermore, CoQ10 administration reduced bone malondialdehyde levels with a concomitant increase in superoxide dismutase levels, thus alleviating SCI­induced oxidative injury. In addition, serum inflammatory cytokine levels were markedly increased in rats post­SCI, which was attenuated by treatment with CoQ10. Finally, the osteoclast­specific genes receptor activator of nuclear factor kappa­B ligand and cathepsin K were significantly upregulated and the osteoblast­specific gene core­binding factor alpha 1 in the femur was downregulated following SCI, which was effectively restored following treatment with CoQ10. The results suggested that CoQ10 treatment may be effective in attenuating SCI­induced osteoporosis.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osteoporose/prevenção & controle , Traumatismos da Medula Espinal/tratamento farmacológico , Ubiquinona/análogos & derivados , Animais , Avaliação Pré-Clínica de Medicamentos , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Fêmur/patologia , Expressão Gênica , Interleucina-6/sangue , Masculino , Osteoblastos/fisiologia , Osteoclastos/fisiologia , Osteoporose/etiologia , Estresse Oxidativo , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/complicações , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tíbia/patologia , Fator de Necrose Tumoral alfa/sangue , Ubiquinona/administração & dosagem
13.
Lasers Med Sci ; 26(5): 633-40, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21732112

RESUMO

The theory of selective photothermolysis (SP) is used in many fields of laser surgery and medicine. As several parameters and a number of complicated photothermal interactions are involved in SP, numerical simulations have been providing an important and effective way in SP studies. However, with different photothermal models of SP, simulated results differ considerably. In addition, insufficient attention has been paid to tissue pressure variation during SP in these models, so that vessel rupture and other clinical phenomena cannot be explained. A novel photothermal model of SP was proposed using a Monte Carlo method to simulate the laser transport in the tissue, a heat transfer equation with dynamically changing vaporization temperature to calculate the temperature distribution, and the Arrhenius equation to predict the thermal damage. A factor of trapped vaporized tissue water k was introduced to describe the effects on tissue pressure, temperature, and other related parameters. It was shown that the simulation results are affected significantly by k. Temperature and thermal damage volume are almost identical, respectively, to those obtained with models with vaporization at 100°C and models without vaporization when k = 0 and 1, while thermal damage volume is close to that obtained with models of vaporization at 110°C and 130°C, respectively, when k = 0.022 and k = 0.18. To some extent, the current models without vaporization and models with vaporization at constant temperature can be regarded as special cases at specific situations of this new photothermal model of SP. In addition, more descriptive simulation results, such as temperature, thermal damage, and pressure, are accessible with this model, although the accuracy depends on the value of k, the estimation of which is planned as future work.


Assuntos
Terapia a Laser/métodos , Simulação por Computador , Procedimentos Cirúrgicos Dermatológicos , Temperatura Alta/uso terapêutico , Humanos , Terapia a Laser/estatística & dados numéricos , Modelos Biológicos , Método de Monte Carlo , Pele/irrigação sanguínea , Temperatura , Termodinâmica , Volatilização
14.
Space Med Med Eng (Beijing) ; 16(1): 44-7, 2003 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12728962

RESUMO

OBJECTIVE: To analyze heat transfer process in skin tissues subjected to hot water and thus to predict the extent of scald. METHOD: Basing on Pennes' Bio-heat Equation, a model for characterizing the damage process in tissues was presented and used for its analysis. RESULT: Temperature distribution in the tissues during the process and the time of beginning of scald were numerically obtained. It was found that the effects of different initial temperature distribution, convection coefficients between the hot water and the tissue surfaces, and the temperature of the hot water are significant. CONCLUSION: The transient heat transfer behavior in multi-layer tissues subjected to hot water can be predicted by the present model. It is useful in the clinical diagnosis and therapy for the scald caused by hot water.


Assuntos
Queimaduras/patologia , Temperatura Alta/efeitos adversos , Modelos Biológicos , Pele/patologia , Queimaduras/etiologia , Transferência de Energia , Humanos , Pele/lesões , Temperatura Cutânea , Termodinâmica , Água
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