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1.
Acta Pharmacol Sin ; 39(11): 1725-1734, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29977005

RESUMO

Recent evidence suggests that ClC-3, a member of the ClC family of Cl- channels or Cl-/H+ antiporters, plays a critical role in NADPH oxidase-derived reactive oxygen species (ROS) generation. However, the underling mechanisms remain unclear. In this study we investigated the effects and mechanisms of ClC-3 on NADPH oxidase activation and ROS generation in endothelial cells. Treatment with angiotensin II (Ang II, 1 µmol/L) significantly elevated ClC-3 expression in cultured human umbilical vein endothelial cells (HUVECs). Furthermore, Ang II treatment increased ROS production and NADPH oxidase activity, an effect that could be significantly inhibited by knockdown of ClC-3, and further enhanced by overexpression of ClC-3. SA-ß-galactosidase staining showed that ClC-3 silencing abolished Ang II-induced HUVEC senescence, whereas ClC-3 overexpression caused the opposite effects. We further showed that Ang II treatment increased the translocation of p47phox and p67phox from the cytosol to membrane, accompanied by elevated Nox2 and p22phox expression, which was significantly attenuated by knockdown of ClC-3 and potentiated by overexpression of ClC-3. Moreover, overexpression of ClC-3 increased Ang II-induced phosphorylation of p47phox and p38 MAPK in HUVECs. Pretreatment with a p38 inhibitor SB203580 abolished ClC-3 overexpression-induced increase in p47phox phosphorylation, as well as NADPH oxidase activity and ROS generation. Our results demonstrate that ClC-3 acts as a positive regulator of Ang II-induced NADPH oxidase activation and ROS production in endothelial cells, possibly via promoting both Nox2/p22phox expression and p38 MAPK-dependent p47phox/p67phox membrane translocation, then increasing Nox2 NADPH oxidase complex formation.


Assuntos
Angiotensina II/metabolismo , Canais de Cloreto/metabolismo , NADPH Oxidase 2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ativação Enzimática/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Imidazóis/farmacologia , NADPH Oxidases/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Transporte Proteico/fisiologia , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1374-7, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30001008

RESUMO

Modern industrial application and technologies require materials with superior mechanical and thermal properties. Kevlar fibers have been known as fibrous materials with good properties of high strength and high decomposition temperature which have become a hot research field in recent years. The properties of fibrous materials depend on their structures and compositions. Thermal decomposition processing of the materials is of great significance for their structures and thermal properties. As a new technique, thermogravimetric (TG) analysis coupled with Fourier transform infrared spectroscopy(FTIR), are able to analyze materials not only qualitatively but also quantitatively. This method has obvious advantages in researching the thermal decomposition of many materials. However, the thermal decomposition processing of Kevlar fibers is rarely reported in the literature, therefore, we firstly studied the pyrolysis behavior of Kevlar fibers with thermogravimetric analysis coupled with Fourier transform infrared spectroscopy at the temperature of 30~800 ℃. We not only obtained the processing of the Kevlar fibers' thermal decomposition with great details but also the products of every stage. Experimental results exhibited that the decomposition of Kevlar fibers has experienced three stages: 100~240, 240~420 and 420~800 ℃. The weight loss of Kevlar fibers was quite slow before 500 ℃. The third stage was the main stage of the decomposition, and the amount of residue finally reached to a mass percent of 56.21%. FTIR analysis illustrated that free water released from Kevlar fibers at the first stage, followed by the dehydration and depolymerization which made polymer chains short. Finally the fiber fragments further reacted and produced the gases of small molecular mass, and the main products were water, ammonia, carbon monoxide and carbon dioxide. Generation rate of water was increased; the emission of ammonia was at the same rate; carbon monoxide was only produced at the temperature of 515~630 ℃, then turned into carbon dioxide. The release of carbon dioxide was on rise because of the conversion process of carbon monoxide, and then dropped to a certain value.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-250692

RESUMO

<p><b>OBJECTIVE</b>To study measurement methods of acromioclavicular and coracoclavicular ligament injuries,its therapeutic effects and complications during internal fixation operation for the treatment of fresh acromioclavicular joint dislocations of Tossy type III.</p><p><b>METHODS</b>From July 2003 to May 2012,127 patients with acromioclavicular joint dislocations of Tossy type III were treated with wire fixation from coracoid process to clavicle or hook-plate fixation. The patients were divided into group A (63 cases) and group B (64 cases) according to whether acromioclavicular ligament and coracoclavicular ligament were repaired or not. In group A (ligaments repaired), there were 39 males and 24 females with an average age of (33.25 +/- 8.46) years old (ranged from 17 to 59 years). And in group B (no ligaments repaired), there were 41 males and 23 females with an average age of (34.10 +/- 7.19) years (ranged from 19 to 57 years). The operation times, intraoperative blood loss, postoperative infections, internal fixation failure, recurrence and other complications, together with therapeutic effects were compared between two groups.</p><p><b>RESULTS</b>The outcome was analyzed according to Karlsson standard. In group A, 54 patients got an excellent result and 9 good according to Karlsson standard;the average operative time was (55.90 +/- 26.56) min; the average intraoperative bleeding amount was (99.80 +/- 50.30) ml; 1 patient had wire broken without re-dislocation at 16 weeks after operation, 3 patients got wound fat liquefaction and recovered after treatment, 1 patient had pain after shoulder joint motion and pain disappeared after implants were taken out. In group B, 52 patients got an excellent result and 12 good according to Karlsson standard; the average operative time was (49.50 +/- 23.14) min; the average intraoperative bleeding amount was (87.30 +/- 46.41) ml; 2 patients got wound fat liquefaction, and 2 patients had pain after shoulder joint motion. All the patients were followed up, and the duration ranged from 9 to 16 months. All internal steel-wire or hook plate were taken out during 4 to 9 months without acromioclavicular joint re dislocation. There were no significant difference in the average operative time, the average intraoperative blood less, complication recurrence rates of fixation failure, wound fat liquefaction, postoperative infection, acromioclavicular joint re-dislocation, and therapeutic effects between two groups.</p><p><b>CONCLUSION</b>Both wire and clavicular hook plate fixation, performed for fresh acromioclavicular joint dislocation with Tossy type III, are simple, effective, less invasive method with less blood loss. In addition, the treatment without ligaments repaired could not increase incidence of complications.</p>


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Articulação Acromioclavicular , Diagnóstico por Imagem , Ferimentos e Lesões , Cirurgia Geral , Estudos de Casos e Controles , Clavícula , Luxações Articulares , Diagnóstico por Imagem , Cirurgia Geral , Ligamentos , Diagnóstico por Imagem , Ferimentos e Lesões , Cirurgia Geral , Procedimentos Ortopédicos , Métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-301799

RESUMO

<p><b>OBJECTIVE</b>To explore the reason, key diagnosic point and therapeutic method of the incisions fat colliquation or infections at early stage after operation of lumbar disc herniation.</p><p><b>METHODS</b>From July 2007 to May 2012, clinical data of 11 patients with incision fat liquefaction or early infection after lumbar discectomy were retrospectively analyzed. There were 5 males and 6 females with an average age of 43.1 years, and the mean time of incisions fat colliquation or infection was 5 days and a half after operation. The main clinical features included local wound pain aggravating, fervescence, fresh seepage in the wound, and blood inflammatory index increased, etc. The wound could heal at the first treatment stage or not was an evaluation standard of curative effect.</p><p><b>RESULTS</b>All patients were followed up with an average period of 21 months. The wounds of 10 cases healed at the first stage without recurrence and complications. In 1 case infected by staphylococcus aureus, distal part of the wound present local red, swelling and with wave motion at 2 months after operation, staphylococcus aureus infection was confirmed after puncture and bacterial culture, and 1 thrum was found after local incision. The wound healed after change dressings for 1 week, without recurrence after followed up for 13 months.</p><p><b>CONCLUSION</b>Preventing the risk factors before operation, minimizing invasive technique during operation reasonable antibiotics application for the lumbar operation reguiring placement objects, and correctly handling with wound after operation could prevent and reduce the incidence of incisions fat liquefaction or infection after operation of lumbar disc herniation. For incision fat liquefaction or infection, early diagnosis, debridement, VSD negative pressure irrigation and drainage, to choosing sensitive antibiotics according to the results of drug sensitivity, may contribute to wound early healing and decrease complication.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tecido Adiposo , Patologia , Deslocamento do Disco Intervertebral , Cirurgia Geral , Vértebras Lombares , Cirurgia Geral , Infecções Estafilocócicas , Patologia , Terapêutica , Infecção da Ferida Cirúrgica , Patologia , Terapêutica , Fatores de Tempo
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(8): 1293-6, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16329504

RESUMO

A diffuse reflectance spectroscopic method was developed to investigate relics conservation with a self-made fiber optics reflectance spectrophotometer. With this technique (1) identifying pigments on the color relics was done by comparing the shapes of reflectance spectra and the positions of reflectance peaks or first derivative peaks with those of related standard pigments; (2) changes of surface states of metals were monitored. From the investigation on the reflectance spectra of copper and its rust product, we can easily get some information about the metal surface, so diffuse reflectance spectroscopy shows special function in the research on metal surface; (3) the diffuse reflectance spectroscopic characteristics of the materials used in protection and restoration of cultural heritages were studied, which can help us choose proper protecting and restoring materials. From our studies it was verified that diffuse reflectance spectroscopy is a quick, simple and non-destructive analytical technique. The study makes diffuse reflectance spectroscopy a new means for relic protection, and opens a new application area for diffuse reflectance spectroscopy as well.


Assuntos
Corantes/análise , Cobre/análise , Pintura/análise , Espectrofotometria/métodos , Corantes/química , Cobre/química , Fibras Ópticas , Refratometria/instrumentação , Refratometria/métodos , Reprodutibilidade dos Testes , Espectrofotometria/instrumentação , Propriedades de Superfície , Fatores de Tempo , Difração de Raios X
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