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1.
World J Clin Cases ; 11(35): 8310-8319, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38130623

RESUMO

BACKGROUND: There are many available treatment options for keloid; however, single treatments are usually less effective. Therefore, more scientifically rational and effective combined treatment methods should be sought to solve the pain associated with keloids. AIM: To explore the efficacy and safety of surgical resection and ultra-reduced tension suture combined with superficial radiation as keloid treatment. METHODS: Fifteen keloid patients admitted to Qingdao Eighth People's Hospital from June 2020 to January 2022 were enrolled in this retrospective analysis. All patients underwent a comprehensive treatment approach comprising surgical resection, ultra-reduced tension suture incision, and superficial radiation therapy within 24 h postoperatively. The modified Vancouver Scar Scale (mVSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to evaluate the treatment effect, whereas the efficacy, adverse effects, and recurrence rate were observed according to the 12-mo follow-up after treatment. RESULTS: The mVSS and POSAS scores at 1 and 6 mo after combination treatment decreased compared to before treatment (P < 0.001), and the overall response rate was 93.3%. Only one case recurred, yielding a 6.7% recurrence rate. The incidence of local chromour sedimentation rate in 1-3 mo after radiotherapy was 33.3% (5 patients), all subsiding after 6-9 mo, without complications, such as delayed wound healing or dermatitis. CONCLUSION: Surgical resection, super subtraction sutures, and superficial radiotherapy are treatment methods with short courses, low recurrence rates, and good safety profiles.

2.
J Org Chem ; 87(5): 3834-3840, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35168320

RESUMO

A practical copper-catalyzed nitration of electron-rich arenes with trimethylsilyl chloride and guanidine nitrate is reported. A variety of nitrated products were generated in moderate to excellent yields (32-99%) at ambient temperature under acid-free, open-flask, and operationally simple conditions.

3.
Mikrochim Acta ; 188(2): 33, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33415494

RESUMO

Fe3O4@MIL-100 (Fe)/PEI are used for the first time as an adsorbent material for the extraction of pesticide residues (epoxiconazole, flusilazole, tebuconazole, and triadimefon) from food matrices. The adsorbent proposed (Fe3O4@MIL-100(Fe)/PEI) was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), thermogravimetric (TG) analysis, and vibrating sample magnetometer (VSM) techniques to evaluate the properties of the sorbent. Then, the Fe3O4@MIL-100 (Fe)/PEI was employed for the quantification of the four triazole fungicides in fruits and vegetables (apple, orange, tomato, cabbage, and cucumber) using HPLC-UV for separation and detection. During the extraction process, the main parameters such as amount of adsorbent, extraction time, pH value, ionic strength, eluting solvent, and eluting volume were optimized. Under the optimum conditions, good linearity of this method was observed for all analytes, with correlation coefficients (R2) ≥ 0.9908. The limits of detection (LODs) ranged from 0.021-3.04 µg kg-1. The extraction recoveries of the four triazole fungicides varied from 73.9 to 109.4% with relative standard deviations (RSD) in the range 0.5 to 6.2%. Compared with other MOFs, the modification of Fe3O4@MIL-100 (Fe) with PEI shows high efficient adsorption due to the combined benefits of MIL-100 (Fe) and PEI. The material is easily synthesized, has good stability, and is of low cost.  Graphical abstract.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/isolamento & purificação , Estruturas Metalorgânicas/química , Resíduos de Praguicidas/isolamento & purificação , Polietilenoimina/química , Triazóis/isolamento & purificação , Adsorção , Cromatografia Líquida de Alta Pressão , Fungicidas Industriais/análise , Fungicidas Industriais/química , Limite de Detecção , Nanopartículas de Magnetita/química , Magnoliopsida/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Extração em Fase Sólida/métodos , Espectrofotometria Ultravioleta , Triazóis/análise , Triazóis/química
4.
J Chromatogr Sci ; 59(1): 95-102, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078200

RESUMO

A novel magnetic solid-phase extraction technique coupled to ultraperformance liquid chromatography has been developed for separation and preconcentration of four sulfonylurea herbicides (sulfosulfuron, bensulfuron-methyl, pyrazosulfuron-ethyl and halosulfuro-methyl) in aqueous samples. The key point of this method was the application of a novel magnetic nanomaterial that composed of a low eutectic solvent as a shell coated on the magnetic core modified by polydopamine. The extensive active sites outside the low eutectic solvent can effectively adsorb the target herbicide in the extraction process. The obtained magnetic adsorbent was characterized with fourier transform infrared spectrometry, scanning electron microscopy and vibrating sample magnetometer. The influence parameters relevant to this method were optimized. Under the optimum conditions, good linearities could be obtained within the range of 1.0-200 µg L-1 for all analytes, with correlation coefficients ≥0.9908. The limit of detections of the method was between 0.0074 and 0.0100 µg L-1 and the relative standard deviations were 1.1-3.6%. The enrichment factor is 66.6. In the final experiment, the proposed method was successfully applied to the analysis of sulfonylurea herbicides residue in environment and drinking-water samples, and the obtained recoveries were between 70.6% and 109.4%.

6.
Front Chem ; 8: 102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32211372

RESUMO

Tough gel with extreme temperature tolerance is a class of soft materials having potential applications in the specific fields that require excellent integrated properties under subzero temperature. Herein, physically crosslinked Europium (Eu)-alginate/polyvinyl alcohol (PVA) organohydrogels that do not freeze at far below 0°C, while retention of high stress and stretchability is demonstrated. These organohydrogels are synthesized through displacement of water swollen in polymer networks of hydrogel to cryoprotectants (e.g., ethylene glycol, glycerol, and d-sorbitol). The organohydrogels swollen water-cryoprotectant binary systems can be recovered to their original shapes when be bent, folded and even twisted after being cooled down to a temperature as low as -20 and -45°C, due to lower vapor pressure and ice-inhibition of cryoprotectants. The physical organohydrogels exhibit the maximum stress (5.62 ± 0.41 MPa) and strain (7.63 ± 0.02), which is about 10 and 2 times of their original hydrogel, due to the synergistic effect of multiple hydrogen bonds, coordination bonds and dense polymer networks. Based on these features, such physically crosslinked organohydrogels with extreme toughness and wide temperature tolerance is a promising soft material expanding the applications of gels in more specific and harsh conditions.

7.
Molecules ; 25(3)2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-31991928

RESUMO

A highly efficient sulfonylation of para-quinone methides with sulfonyl hydrazines in water has been developed on the basis of the mode involving a tetrabutyl ammonium bromide (TBAB)-promoted sulfa-1,6-conjugated addition pathway. This reaction provides a green and sustainable method to synthesize various unsymmetrical diarylmethyl sulfones, showing good functional group tolerance, scalability, and regioselectivity. Further transformation of the resulting diarylmethyl sulfones provides an efficient route to some functionalized molecules.


Assuntos
Indolquinonas/química , Compostos de Amônio Quaternário/química , Sulfonas/química , Água/química , Catálise , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Solventes , Temperatura
8.
Chem Commun (Camb) ; 55(66): 9809-9812, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31360958

RESUMO

A novel tandem intermolecular ammonium ylide formation/intramolecular Mannich-type [5+1] cyclization reaction of aryl diazoacetates and ortho-aminophenyl imine derivatives was developed. The reaction provides an efficient methodology for direct synthesis of diverse trisubstituted tetrahydroquinoxalines bearing a quaternary stereogenic carbon center in moderate to good yields with excellent diastereoselectivity. This process features high efficiency, mild reaction conditions, and high stereoselectivity.

9.
Biomed Mater ; 10(6): 065018, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26657457

RESUMO

To assess the effect of basic fibroblast growth factor-binding extracellular matrix (bFGF-ECM) combined with bone marrow mesenchymal stem cells (BMSCs) transplantation on acute myocardial infarction (AMI) and explore the underlying mechenisms. Rabbit hearts were processed by decellularization with sodium dodecyl sulfate (SDS) perfusion, heparin immobilization, bFGF-binding and homogenization, for preparation of bFGF-binding cardiac ECM suspension (bFGF-ECM). Thereafter, the characteristics of bFGF release were analyzed in vitro. Following ligation of the mid-third of the left anterior descending artery, the rabbits were divided into a control group (no treatment), BMSCs group (BMSCs transplantation), bFGF-ECM group (bFGF-ECM implantation), and BMSCs + bFGF-ECM group (BMSCs and bFGF-ECM implantation). Apoptosis and differentiation of implanted BMSCs, and the left ventricular (LV) remodeling and function were assessed. The ex vivo proliferation, apoptosis, migration and differentiation of BMSCs were determined after exposure to bFGF and/or ECM. The ECM could sustainably release bFGF. 24 h and 6 weeks after the operation, improved viability and differentiation of the implanted BMSCs, as well as inhibited dilatation and preserved function of the left ventricle (LV), were significant in the BMSCs + bFGF-ECM group compared with other groups (P < 0.05), although BMSCs and ECM-bFGF groups also showed better results than control group (P < 0.05). Additionally, ECM and bFGF showed a synergistic effect on BMSCs proliferation, viability, migration and differentiation. The combination of bFGF-binding ECM and BMSCs implantation may promote myocardial regeneration and LV function, and become a new strategy for the treatment of AMI.


Assuntos
Matriz Extracelular/transplante , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Transplante de Células-Tronco Mesenquimais/instrumentação , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Alicerces Teciduais , Absorção Fisico-Química , Doença Aguda , Animais , Transplante de Medula Óssea/instrumentação , Implantes de Medicamento/administração & dosagem , Implantes de Medicamento/síntese química , Matriz Extracelular/química , Fator 2 de Crescimento de Fibroblastos/química , Ligação Proteica , Coelhos , Resultado do Tratamento
10.
Cell Prolif ; 48(6): 661-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26466964

RESUMO

OBJECTIVES: To explore effects of hepatocyte growth factor (HGF) combined with insulin-like growth factor 1 (IGF-1) on transplanted bone marrow mesenchymal stem cells (BMSCs), for treatment of acute myocardial ischaemia. MATERIALS AND METHODS: After ligation of the left anterior descending artery, rabbits were divided into a Control group, a Factors group (HGF+IGF-1), a BMSC group and a Factors+BMSCs group. Allogenous BMSCs (1 × 10(7)) and/or control-released microspheres of 2 µg HGF+2 µg IGF-1 were intramyocardially injected into infarcted regions. Apoptosis and differentiation of implanted BMSCs, histological and morphological results, and cardiac remodelling and function were evaluated at different time points. In vitro, BMSCs were exposed to HGF, IGF-1 and both (50 ng/ml) and subsequently proliferation, migration, myocardial differentiation and apoptosis induced by hypoxia, were analysed. RESULTS: Four weeks post-operatively, the above indices were significantly improved in Factors+BMSCs group compared to the others (P < 0.01), although Factors and BMSCs group also showed better results than Control group (P < 0.05). In vitro, HGF promoted BMSC migration and differentiation into cardiomyocytes, but inhibited proliferation (P < 0.05), while IGF-1 increased proliferation and migration, and inhibited apoptosis induced by hypoxia (P < 0.05), but did not induce myocardial differentiation. Combination of HGF and IGF-1 significantly promoted BMSCs capacity for migration, differentiation and lack of apoptosis (P < 0.05). CONCLUSIONS: Combination of HGF and IGF-1 activated BMSCs complementarily, and controlled release of the two factors promoted protective potential of transplanted BMSCs to repair infarcted myocardium. This suggests a new strategy for cell therapies to overcome acute ischemic myocardial injury.


Assuntos
Fator de Crescimento de Hepatócito/uso terapêutico , Fator de Crescimento Insulin-Like I/uso terapêutico , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos/citologia , Animais , Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Transplante de Medula Óssea , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Vasos Coronários/cirurgia , Modelos Animais de Doenças , Quimioterapia Combinada , Transplante de Células-Tronco Mesenquimais , Neovascularização Fisiológica/efeitos dos fármacos , Coelhos
11.
Cardiovasc Ther ; 33(4): 184-92, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25959676

RESUMO

OBJECTIVE: To investigate the effects of immature cardiomyocytes differentiated from c-kit(+) bone marrow mesenchymal stem cells (BMSCs) against acute myocardial infarction (AMI). METHODS: Miniswine passage 8 BMSCs were enriched for c-kit and induced by 5 µM 5-azacytidine (AZA) for 14 days, and a second enrichment for the dihydropyridine receptor subunit α2δ1 was performed (enriched BMSCs). Thereafter, enriched BMSCs were analyzed by determining cardiac differentiation, secretion function, and the effects of these secreted factors on cardiac stem cells (CSCs). Miniswine with AMI were divided into control, primary BMSCs' (PB), and enriched BMSCs' (EB) groups. Autologous BMSCs were intramyocardially injected into the ischemic regions in PB and EB groups. The following indices were evaluated at different time points, including paracrine of implanted BMSCs, histological and morphological analysis, myocardial perfusion, and cardiac function. RESULTS: As shown by in vitro study, enrichment + AZA significantly promoted BMSCs to express cardiac-specific markers and format action potential, but down-regulated the expression of VEGF and bFGF, consequently attenuated BMSCs-inducing CSCs proliferation, migration, and differentiation. The in vivo experiments revealed similar results like the in vitro 6 weeks postoperatively. And in EB group, there were decreased angiogenesis and myocardial perfusion, attenuated resident CSCs-mediated myocardial regeneration, and consequently impaired cardiac function compared with PB group. CONCLUSIONS: This pretreatment promoted BMSCs to differentiate into myocardiocytes both in vitro and in vivo, but impaired their paracrine function and effects on resident CSCs, suggesting that inducing cardiac differentiation alone may not improve protective effects of BMSCs transplantation on AMI.


Assuntos
Diferenciação Celular , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/cirurgia , Miocárdio/metabolismo , Miócitos Cardíacos/transplante , Proteínas Proto-Oncogênicas c-kit/metabolismo , Regeneração , Animais , Azacitidina/farmacologia , Canais de Cálcio Tipo L/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Circulação Coronária , Modelos Animais de Doenças , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neovascularização Fisiológica , Comunicação Parácrina , Fenótipo , Suínos , Porco Miniatura , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Função Ventricular Esquerda , Fator de von Willebrand/metabolismo
12.
Bioresour Technol ; 114: 365-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22516249

RESUMO

The feasibility of fungal pretreatment of cornstalk with Phanerochaete chrysosporium for enzymatic saccharification and H(2) production was investigated in this study. Firstly, cornstalk was pretreated with P. chrysosporium at 29 °C under static condition for 15 d, lignin reduction was up to 34.3% with holocellulose loss less than 10%. Microscopic structure observation combined FTIR analysis further demonstrated that the lignin and crystallinity were decreased. Subsequently, the fungal-pretreated cornstalk was subjected to enzymatic hydrolysis by the crude cellulase from Trichoderma viride to produce fermentable sugars which were then fermented to bio-H(2) using Thermoanaerobacterium thermosaccharolyticum W16. The maximum enzymatic saccharification was found to be 47.3% which was 20.3% higher than the control without pretreatment. Upon fermentation of enzymatic hydrolysate, the yield of H(2) was calculated to be 80.3 ml/g-pretreated cornstalk. The present results suggested the potential of using hydrogen-producing bacteria for high-yield conversion of cornstalk into bio-H(2) integrate with biological pretreatment and enzymatic saccharification.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Hidrogênio/isolamento & purificação , Hidrogênio/metabolismo , Resíduos Industriais/prevenção & controle , Phanerochaete/metabolismo , Componentes Aéreos da Planta/microbiologia , Zea mays/microbiologia
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