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1.
J Proteome Res ; 23(1): 3-15, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38018860

RESUMO

The purpose of this study was to determine potential metabolic biomarkers and therapeutic drugs in the gingival tissue of individuals with periodontitis. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) were used to analyze the gingival tissue samples from 20 patients with severe periodontitis and 20 healthy controls. Differential metabolites were identified using variable important in projection (VIP) values from the orthogonal partial least squares discrimination analysis (OPLS-DA) model and then verified for significance between groups using a two-tailed Student's t test. In total, 65 metabolites were enriched in 33 metabolic pathways, with 40 showing a significant increase and 25 expressing a significant decrease. In addition, it was found that patients with severe periodontitis have abnormalities in metabolic pathways, such as glucose metabolism, purine metabolism, amino acid metabolism, and so on. Furthermore, based on a multidimensional analysis, 12 different metabolites may be the potential biomarkers of severe periodontitis. The experiment's raw data have been uploaded to the MetaboLights database, and the project number is MTBLS8357. Moreover, osteogenesis differentiation characteristics were detected in the selected metabolites. The findings may provide a basis for the study of diagnostic biomarkers and therapeutic metabolites in severe periodontitis.


Assuntos
Metabolômica , Periodontite , Humanos , Metabolômica/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metaboloma , Biomarcadores
2.
J Virol ; 97(8): e0018123, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37565750

RESUMO

Vacuolar protein sorting 28 (Vps28), a component of the ESCRT-I (endosomal sorting complex required for transport I), plays an important role in the pathogen life cycle. Here, we investigated the reciprocal regulation between Vps28 and the foot-and-mouth disease virus (FMDV). Overexpression of Vps28 decreased FMDV replication. On the contrary, the knockdown of Vps28 increased viral replication. Subsequently, the mechanistic study showed that Vps28 destabilized the replication complex (RC) by associating with 3A rather than 2C protein. In addition, Vps28 targeted FMDV VP0, VP1, and VP3 for degradation to inhibit viral replication. To counteract this, FMDV utilized tactics to restrict Vps28 to promote viral replication. FMDV degraded Vps28 mainly through the ubiquitin-proteasome pathway. Additional data demonstrated that 2B and 3A proteins recruited E3 ubiquitin ligase tripartite motif-containing protein 21 to degrade Vps28 at Lys58 and Lys25, respectively, and FMDV 3Cpro degraded Vps28 through autophagy and its protease activity. Meantime, the 3Cpro-mediated Vps28 degradation principally alleviated the ability to inhibit viral propagation. Intriguingly, we also demonstrated that the N-terminal and C-terminal domains of Vps28 were responsible for the suppression of FMDV replication, which suggested the elaborated counteraction between FMDV and Vps28. Collectively, our results first investigate the role of ESCRTs in host defense against picornavirus and unveil underlying strategies utilized by FMDV to evade degradation machinery for triumphant propagation. IMPORTANCE ESCRT machinery plays positive roles in virus entry, replication, and budding. However, little has been reported on its negative regulation effects during viral infection. Here, we uncovered the novel roles of ESCRT-I subunit Vps28 on FMDV replication. The data indicated that Vps28 destabilized the RC and impaired viral structural proteins VP0, VP1, and VP3 to inhibit viral replication. To counteract this, FMDV hijacked intracellular protein degradation pathways to downregulate Vps28 expression and thus promoted viral replication. Our findings provide insights into how ESCRT regulates pathogen life cycles and elucidate additional information regarding FMDV counteraction of host antiviral activity.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Vírus da Febre Aftosa/metabolismo , Proteínas Virais/metabolismo , Transdução de Sinais , Transporte Proteico , Replicação Viral/fisiologia
3.
Arch Microbiol ; 205(4): 145, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971856

RESUMO

Polyurethane (PU) is a versatile plastic that boasts high environmental resistance. The biodegradation of PU has become a hot topic of research aimed at finding ways to potentially solve PU pollutants. Identifying microorganisms capable of efficiently degrading PU plastics is pivotal for the development of a green recycling process for PU. This study aimed to isolate and characterize PU-degrading fungi from the soil of a waste transfer station in Luoyang, China. We isolated four different fungal strains from the soil. Among the isolates, the P2072 and P2073 strains were identified as Rhizopus oryzae (internal transcribed spacer identity, 99.66%) and Alternaria alternata (internal transcribed spacer identity, 99.81%), respectively, through microscopic, morphologic, as well as 18S rRNA sequencing. The degradation ability of strains P2072 and P2073 was analyzed through measurement of weight loss, and they exhibited a degradation rate of 2.7% and 3.3%, respectively, for the PU films after 2 months' growth in mineral salt medium (MSM) with PU films as the sole carbon source. In addition, the P2073 strain exhibited protease activity in the presence of PU. To our knowledge, R. oryzae has never been reported as a PU-degrading fungus. This study provides a new perspective on the biodegradation of PU.


Assuntos
Poluentes Ambientais , Poliuretanos , Poliuretanos/metabolismo , Solo , Microbiologia do Solo , Fungos/genética , Fungos/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo
4.
Appl Microbiol Biotechnol ; 107(19): 6057-6070, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37526695

RESUMO

Poly(butylene adipate-co-terephthalate) (PBAT), a promising biodegradable aliphatic-aromatic copolyester material, can be applied as an alternative material to reduce the adverse effects of conventional plastics. However, the degradation of PBAT plastics in soil is time-consuming, and effective PBAT-degrading microorganisms have rarely been reported. In this study, the biodegradation properties of PBAT by an elite fungal strain and related mechanisms were elucidated. Four PBAT-degrading fungal strains were isolated from farmland soils, and Purpureocillium lilacinum strain BA1S showed a prominent degradation rate. It decomposed approximately 15 wt.% of the PBAT films 30 days after inoculation. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Liquid chromatography mass spectrometry (LC‒MS) were conducted to analyze the physicochemical properties and composition of the byproducts after biodegradation. In the presence of PBAT, the lipolytic enzyme activities of BA1S were remarkably induced, and its cutinase gene was also significantly upregulated. Of note, the utilization of PBAT in BA1S cells was closely correlated with intracellular cytochrome P450 (CYP) monooxygenase. Furthermore, CreA-mediated carbon catabolite repression was confirmed to be involved in regulating PBAT-degrading hydrolases and affected the degradation efficiency. This study provides new insight into the degradation of PBAT by elite fungal strains and increases knowledge on the mechanism, which can be applied to control the biodegradability of PBAT films in the future. KEY POINTS: • Purpureocillium lilacinum strain BA1S was isolated from farmland soils and degraded PBAT plastic films at a prominent rate. • The lipolytic enzyme activities of strain BA1S were induced during coculture with PBAT, and the cutinase gene was significantly upregulated during PBAT degradation. • CreA-mediated carbon catabolite repression of BA1S plays an essential role in regulating the expression of PBAT-degrading hydrolases.


Assuntos
Plásticos , Poliésteres , Poliésteres/metabolismo , Adipatos , Solo , Hidrolases
5.
Clin Oral Implants Res ; 34(7): 707-718, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37167364

RESUMO

OBJECTIVES: This clinical study aimed to assess the accuracy of implant positions using a robotic system in partially edentulous patients. MATERIALS AND METHODS: Twenty-eight partially edentulous patients received 31 implants using the robotic system. Deviations between the planned and placed implants were calculated after surgery. The deviations were compared with objective performance goals (OPGs) from reported studies of fully guided static computer-assisted implant surgery (CAIS) and dynamic CAIS. A multiple linear regression analysis was performed to investigate the possible effects of the type and side of the arch, implant location, and implant dimensions on the deviations. RESULTS: The evaluation of 31 implants resulted in a mean angle deviation of 2.81 ± 1.13° (95% confidence interval (CI): 2.40-3.23°), while the 3D deviations at the implant shoulder and apex were 0.53 ± 0.23 mm (95% CI 0.45-0.62 mm) and 0.53 ± 0.24 mm (95% CI 0.44-0.61 mm), respectively. The upper limits of the 95% CI of 3D deviations were lower than those of the corresponding OPGs; however, the angle deviation was similar to that of the OPG. No statistically significant differences were found for the type and side of the arch, implant location, and implant dimensions to the deviations (p > .05). CONCLUSIONS: The robotic system appears to achieve higher accuracy in implant positions than static and dynamic CAIS in partially edentulous patients (Chinese Clinical Trial Registry ChiCTR2300067587).


Assuntos
Implantes Dentários , Boca Edêntula , Procedimentos Cirúrgicos Robóticos , Cirurgia Assistida por Computador , Humanos , Implantação Dentária Endóssea/métodos , Estudos Prospectivos , Tomografia Computadorizada de Feixe Cônico , Desenho Assistido por Computador , Imageamento Tridimensional , Planejamento de Assistência ao Paciente , Boca Edêntula/cirurgia , Cirurgia Assistida por Computador/métodos
6.
Anal Chem ; 94(2): 1318-1324, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34928126

RESUMO

Human pepsin is a digestive protease that plays an important role in the human digestive system. The secondary structure of human pepsin determines its bioactivity. Therefore, an in-depth understanding of human pepsin secondary structure changes is particularly important for the further improvement of the efficiency of human pepsin biological function. However, the complexity and diversity of the human pepsin secondary structure make its analysis difficult. Herein, a convenient method has been developed to quickly detect the secondary structure of human pepsin using a portable Raman spectrometer. According to the change of surface-enhanced Raman spectroscopy (SERS) signal intensity and activity of human pepsin at different pH values, we analyze the change of the human pepsin secondary structure. The results show that the content of the ß-sheet gradually increased with the increase in the pH in the active range, which is in good agreement with circular dichroism (CD) measurements. The change of the secondary structure improves the sensitivity of human pepsin SERS detection. Meanwhile, human pepsin is a commonly used disease marker for the noninvasive diagnosis of gastroesophageal reflux disease (GERD); the detection limit of human pepsin we obtained is 2 µg/mL by the abovementioned method. The real clinical detection scenario is also simulated by spiking pepsin solution in saliva, and the standard recovery rate is 80.7-92.3%. These results show the great prospect of our method in studying the protein secondary structure and furthermore promote the application of SERS in clinical diagnosis.


Assuntos
Refluxo Gastroesofágico , Pepsina A , Refluxo Gastroesofágico/diagnóstico , Humanos , Saliva/química , Análise Espectral Raman/métodos
7.
Biomacromolecules ; 23(6): 2264-2271, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35324155

RESUMO

With the emergence of efficient green solvents, structural regulation of regenerated cellulose is highly desired in the solution process from an industrial perspective. Cellulose fiber and films are viewed as a "composite" comprising amorphous and crystalline fractions. The regulation of the crystalline structure is of great importance for the properties of cellulose materials. In this study, we found stretch-induced crystallization behavior during the transition from solution to gel via coagulation. The crystallinity index of the hydrogel fiber increases with the stretch ratio (SR). X-ray diffraction revealed that the cellulose II hydrate formed in the stretched hydrogel fibers. The mechanical properties and thermal stability of the dry fibers greatly improved against the SR. This crystallization behavior depends on the concentration of the solution and the type of ionic liquid. This stretch-induced crystallization provides an efficient method for structural regulation in cellulose solution processing.


Assuntos
Líquidos Iônicos , Celulose/química , Cristalização , Hidrogéis , Líquidos Iônicos/química , Difração de Raios X
8.
Environ Res ; 204(Pt C): 112177, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34717945

RESUMO

Reverse thermally induced separation (RTIPS) was used to obtain a separation membrane with a better internal structure for a higher water flux and a surface that could easily form a hydration layer. In comparison to the traditional modification method, this work focused on the aspect that the internal structure obtained by changing the membrane-making method provided easier adhesion conditions for the dopamine/TiO2 hybrid nanoparticles (DA/TiO2 HNPs) obtained by biomimetic mineralization. It provided a basis for exploring the variation in adhesion with the water bath temperature and the amount of titanium added through the study of turbidity point, SEM images, water contact angle, thermogravimetric test, EDX, AFM, XPS, FTIR and other test results. The SEM images proved that the membrane obtained through the RTIPS method had a porous surface and spongy internal structure, furthermore, additional polymers were adsorbed. Use of EDX demonstrated that biomimetic mineralization prevented the production of agglomerated titanium dioxide. XPS and FTIR spectra confirmed the introduction and immobilization of HNP aggregation. Moreover, a decrease in the surface roughness and water contact angle further suggested an improvement in the hydrophilicity of the modified membrane. The introduction of HNP at a higher water bath temperature helped increase the water flux up to ten times, moreover, the oil-water separation efficiency could still reach over 99.50%. Lastly, a cycle test of the modified membrane under the optimal conditions helped confirm that the membrane forming conditions at this time could provide a better environment for the formation of the hydrophilic layer, which was conducive to the recycling of the separation membrane. In summary, more fixed more hydrophilic particles could be obtained through the RTIPS method based on biomimetic mineralization to prevent the accumulation of titanium dioxide, thus helping improve permeability and anti-fouling of the membrane.


Assuntos
Biônica , Membranas Artificiais , Polímeros/química , Sulfonas
9.
Appl Microbiol Biotechnol ; 102(3): 1297-1306, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29204897

RESUMO

Cellulose is a highly available and renewable carbon source in nature. However, it cannot be directly metabolized by most microbes including Komagataella phaffii (formerly Pichia pastoris), which is a frequently employed host for heterologous protein expression and production of high-value compounds. A K. phaffii strain was engineered that constitutively co-expresses an endoglucanase and a ß-glucosidase both from Aspergillus niger and an exoglucanase from Trichoderma reesei under the control of bidirectional promoters. This engineered strain was able to grow on cellobiose and carboxymethyl cellulose (CMC) but not on Avicel. However, the detected release of cellobiose from Avicel by using the produced mixture of endoglucanase and exoglucanase as well as the released glucose from Avicel by using the produced mixture of all three cellulases at 50 °C indicated the production of exoglucanase under the liquid culture conditions. The successful expression of three cellulases in K. phaffii demonstrated the feasibility to enable K. phaffii to directly use cellulose as a carbon source for producing recombinant proteins or other high-value compounds.


Assuntos
Celulase/biossíntese , Celulose/metabolismo , Pichia/metabolismo , Proteínas Recombinantes/biossíntese , beta-Glucosidase/biossíntese , Aspergillus niger/enzimologia , Aspergillus niger/genética , Metabolismo dos Carboidratos , Carboximetilcelulose Sódica/metabolismo , Celobiose/metabolismo , Celulase/genética , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Trichoderma/enzimologia , Trichoderma/genética , beta-Glucosidase/genética
10.
Biotechnol Appl Biochem ; 65(2): 145-149, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28436165

RESUMO

Thermophilic Bacillus coagulans JI12 was used to ferment hemicellulose hydrolysate obtained by acid hydrolysis of oil palm empty fruit bunch at 50 °C and pH 6, producing 105.4 g/L of l-lactic acid with a productivity of 9.3 g/L/H by fed-batch fermentation under unsterilized conditions. Simultaneous saccharification and fermentation (SSF) was performed at pH 5.5 and 50 °C to convert both hemicellulose hydrolysate and cellulose-lignin complex in the presence of Cellic Ctec2 cellulases using yeast extract (20 g/L) as the nitrogen source, giving 114.0 g/L of l-lactic acid with a productivity of 5.7 g/L/H. The SSF was also conducted by replacing yeast extract with equal amount of dry Bakers' yeast, achieving 120.0 g/L of l-lactic acid with a productivity of 4.3 g/L/H. To the best of our knowledge, these lactic acid titers and productivities are the highest ever reported from lignocellulose hydrolysates.


Assuntos
Bacillus coagulans/metabolismo , Ácido Láctico/metabolismo , Óleo de Palmeira/metabolismo , Polissacarídeos/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Fermentação , Frutas/metabolismo , Hidrólise , Microbiologia Industrial/métodos , Lignina/metabolismo
12.
Pharm Res ; 34(1): 148-160, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27738951

RESUMO

PURPOSE: To overcome multi-drug resistance (MDR) in tumor chemotherapy, a polymer/inorganic hybrid drug delivery platform with tumor targeting property and enhanced cell uptake efficiency was developed. METHOD: To evaluate the applicability of our delivery platform for the delivery of different drug resistance inhibitors, two kinds of dual-drug pairs (doxorubicin/buthionine sulfoximine and doxorubicin/tariquidar, respectively) were loaded in heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles to realize simultaneous delivery of an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells. RESULTS: Prepared by self-assembly, the drug loaded hybrid nanovesicles with a mean size less than 210 nm and a negative zeta potential exhibit good stability in serum contained aqueous media. The in vitro cytotoxicity evaluation indicates that hybrid nanovesicles with tumor targeting biotin moieties have an enhanced tumor cell inhibitory effect. In addition, dual-drug loaded hybrid nanovesicles exhibit significantly stronger cell growth inhibition as compared with doxorubicin (DOX) mono-drug loaded nanovesicles due to the reduced intracellular glutathione (GSH) content by buthionine sulfoximine (BSO) or the P-glycoprotein (P-gp) inhibition by tariquidar (TQR). CONCLUSIONS: The tumor targeting nanovesicles prepared in this study, which can simultaneously deliver multiple drugs and effectively reverse drug resistance, have promising applications in drug delivery for tumor treatments. The polymer/inorganic hybrid drug delivery platform developed in this study has good applicability for the co-delivery of different anti-tumor drug/drug resistance inhibitor pairs to overcome MDR. Graphical Abstract A polymer/inorganic hybrid drug delivery platform with enhanced cell uptake was developed for tumor targeting synergistic drug delivery. The heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles prepared in this study can deliver an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells simultaneously to overcome drug resistance efficiently.


Assuntos
Antineoplásicos/administração & dosagem , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanopartículas/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Biotina/química , Butionina Sulfoximina/administração & dosagem , Carbonato de Cálcio/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Sinergismo Farmacológico , Glutationa/metabolismo , Células HeLa , Heparina/química , Humanos , Células MCF-7 , Polímeros/química , Protaminas/química , Quinolinas/administração & dosagem
13.
Water Sci Technol ; 2017(1): 300-309, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29698244

RESUMO

This study prepared a carboxylate-functionalized sugarcane bagasse (CF-SCB) from sugarcane bagasse (SCB) via a simple and low-toxicity chemical modification to enhance its capacity for adsorbing methylene blue (MB) from aqueous solutions. The success of chemical modification was confirmed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), the pore area and porosity, and zeta potential measurement analysis. The adsorption capacity of CF-SCB was investigated at different pHs, ionic strengths, temperatures, contact times and initial dye concentrations. Equilibrium data were best described by the Langmuir isotherm model, and the maximum monolayer adsorption capacity of CF-SCB (296.74 mg g-1) was greatly improved compared with SCB (77.16 mg g-1) at 30 °C. The thermodynamic study indicated that MB adsorption onto CF-SCB was a spontaneous, endothermic and entropy increased process. Adsorption kinetics followed a pseudo-second-order mode, and the adsorption mechanism was based on electrostatic interactions. The reusability study showed that CF-SCB had reasonably good reuse potential. All the results suggested that CF-SCB has high potential to be used as an effective and renewable adsorbent for MB removal from wastewater.


Assuntos
Celulose/química , Azul de Metileno/química , Saccharum/química , Poluentes Químicos da Água/química , Adsorção , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Tiazinas , Águas Residuárias , Purificação da Água
14.
Zhonghua Nan Ke Xue ; 23(9): 782-785, 2017 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29726657

RESUMO

OBJECTIVE: To observe the influence of excessive fluoride on the levels of osteocalcin and testosterone in the testis of the male mouse. METHODS: Twenty-four C57BL/6J male mice were equally randomized into a normal control and a fluorosis model group, the former fed on distilled water while the latter on a solution of sodium fluoride (100 mg/L) in distilled water, both for 12 weeks. Then, the level of osteocalcin in the testis tissue was measured with the immunohistochemical streptavidin-peroxidase (SP) method and those of osteocalcin and testosterone in the serum determined by ELISA. RESULTS: After 12 weeks of fluoride intervention, the level of serum osteocalcin was significantly higher in the fluorosis models than in the normal controls (ï¼»68.05 ± 5.32ï¼½ vs ï¼»47.50 ± 5.73ï¼½ pg/mL, F = 11.901, P = 0.008), while that of testosterone markedly lower in the former than the latter group (ï¼»8.07 ± 1.35ï¼½ vs ï¼»12.94 ± 3.09ï¼½ ng/mL, F = 2.313, P = 0.006). The results of immunohistochemical SP showed the expression of osteocalcin in the cell membrane and cytoplasm of the fluorosis models, which was evidently higher than in the normal controls. CONCLUSIONS: Twelve-week intake of 100 mg/L fluoride solution can decrease the level of testosterone and increase the expression of osteocalcin in the testis of the male mouse.


Assuntos
Intoxicação por Flúor/metabolismo , Osteocalcina/metabolismo , Testículo/metabolismo , Animais , Fluoretos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Fluoreto de Sódio/toxicidade , Testículo/efeitos dos fármacos
15.
Langmuir ; 31(18): 5115-22, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25927163

RESUMO

With the aim to develop a facile strategy to prepare functional drug carriers to overcome multidrug resistance (MDR), we prepared heparin/protamine/calcium carbonate (HP/PS/CaCO3) hybrid nanovesicles with enhanced cell internalization, good serum stability, and pH sensitivity for drug delivery. All the functional components including protamine to improve the cell uptake, heparin to enhance the stability, and CaCO3 to improve drug loading and endow the system with pH sensitivity were introduced to the nanovesicles by self-assembly in an aqueous medium. An antitumor drug (doxorubicin, DOX) and a drug resistance inhibitor (tariquidar, TQR) were coloaded in the nanovesicles during self-assembly preparation of the nanovesicles. The drug loaded nanovesicles, which had a mean size less than 200 nm, exhibited a pH-sensitive drug release behavior. In vitro study was carried out in both nonresistant cells (HeLa and MCF-7) and drug-resistant cancer cells (MCF-7/ADR). Because of the enhanced intracellular and nuclear drug accumulation through effective inhibition of the P-gp efflux transporter, DOX/TQR coloaded nanovesicles showed significantly improved tumor cell inhibitory efficiency, especially for drug-resistant cells. These results suggest the self-assembled nanovesicles have promising applications in multidrug delivery to overcome drug resistance in tumor treatments.


Assuntos
Antineoplásicos/química , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Células HeLa , Humanos , Nanoestruturas/química , Quinolinas/química
16.
Langmuir ; 31(17): 5005-13, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25866865

RESUMO

By coating polydimethylsiloxane (PDMS) relief structures with a layer of opaque metal such as gold, the incident light is strictly allowed to pass through the nanoscopic apertures at the sidewalls of PDMS reliefs to expose underlying photoresist at nanoscale regions, thus producing subwavelength nanopatterns covering centimeter-scale areas. It was found that the sidewalls were a little oblique, which was the key to form the nanoscale apertures. Two-sided and one-sided subwavelength apertures can be constructed by employing vertical and oblique metal evaporation directions, respectively. Consequently, two-line and one-line subwavelength nanopatterns with programmable feature shapes, sizes, and periodicities could be produced using the obtained photomasks. The smallest aperture size and line width of 80 nm were achieved. In contrast to the generation of raised positive photoresist nanopatterns in phase shifting photolithography, the recessed positive photoresist nanopatterns produced in this study provide a convenient route to transfer the resist nanopatterns to metal nanopatterns. This nanolithography methodology possesses the distinctive advantages of simplicity, low cost, high throughput, and nanoscale feature size and shape controllability, making it a potent nanofabrication technique to enable functional nanostructures for various potential applications.


Assuntos
Ouro/química , Nanoestruturas/química , Nanotecnologia/métodos , Impressão/métodos , Dimetilpolisiloxanos/química , Elasticidade , Humanos , Luz , Processos Fotoquímicos , Propriedades de Superfície
17.
Langmuir ; 31(3): 1210-7, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25549246

RESUMO

Developing a cost-effective nanolithography strategy that enables the production of subwavelength features with various shapes over large areas is a long-standing goal in the nanotechnology community. Herein, an inexpensive nanolithographic technique that combines the wafer-scale production capability of photolithography with the subwavelength feature size controllability of near-field photolithography was developed to fabricate centimeter-scale up to wafer-scale sub-100-nm variously shaped nanopatterns on surfaces. The wafer-scale elastomeric trench-based photomasks with subwavelength apertures created at the apexes were compatible with mask aligners, allowing for the production of wafer-scale subwavelength nanopatterns with adjustable feature sizes, shapes, and periodicities. The smallest feature sizes of 50 and 80 nm were achieved on positive tone and negative tone photoresist surfaces, respectively, which could be ascribed to a near-field optical effect. The fabricated centimeter-scale nanopatterns were functionalized to study cell-matrix adhesion and migration. Compared to currently developed nanolithographic methods that approach similar functionalities, this facile nanolithographic strategy combines the merits of low cost, subwavelength feature size, high throughput, and varied feature shapes, making it an affordable approach to be used in academic research for researchers at most institutions.


Assuntos
Técnicas Eletroquímicas , Ouro/química , Nanoestruturas/química , Nanotecnologia/métodos , Dimetilpolisiloxanos/química , Elasticidade , Nanotecnologia/instrumentação , Tamanho da Partícula , Polimetil Metacrilato/química , Impressão/métodos
18.
Mol Pharm ; 11(9): 3210-22, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25098949

RESUMO

Faced with the complex medical challenge presented by spinal cord injuries (SCI) and considering the lack of any available curative therapy, the development of a novel method of delivering existing drugs or candidate agents can be perceived to be as important as the development of new therapeutic molecules. By combining three ingredients currently in clinical use or undergoing testing, we have designed a central nervous system targeted delivery system based on apamin-modified polymeric micelles (APM). Apamin, one of the major components of honey bee venom, serves as the targeting moiety, poly(ethylene glycol) (PEG) distearoylphosphatidylethanolamine (DSPE) serves as the drug-loaded material, and curcumin is used as the therapeutic agent. Apamin was conjugated with NHS (N-hydroxysuccinimide)-PEG-DSPE in a site-specific manner, and APM were prepared by a thin-film hydration method. A formulation comprising 0.5 mol % targeting ligand with 50 nm particle size showed strong targeting efficiency in vivo and was evaluated in pharmacodynamic assays. A 7-day treatment by daily intravenous administration of low doses of APM (corresponding to 5 mg/kg of curcumin) was performed. Significantly enhanced recovery and prolonged survival was found in the SCI mouse model, as compared to sham-treated groups, with no apparent toxicity. A single dose of apamin-conjugated polymers was about 700-fold lower than the LD50 amount, suggesting that APM and apamin have potential for clinical applications as spinal cord targeting ligand for delivery of agents in treatment of diseases of the central nervous system.


Assuntos
Apamina/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Apamina/química , Química Farmacêutica/métodos , Curcumina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Camundongos , Micelas , Tamanho da Partícula , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Polímeros/química , Succinimidas/química
19.
Microb Cell Fact ; 13: 157, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25384340

RESUMO

BACKGROUND: Oil palm empty fruit bunch (EFB) is a lignocellulosic waste produced in palm oil industry. EFB mainly consists of cellulose, hemicellulose (mainly xylan) and lignin and has a great potential to be reused. Converting EFB to fermentable sugars and value-added chemicals is a much better choice than treating EFB as waste. RESULTS: A cellulase-producing strain growing on oil palm empty fruit bunch (EFB) was isolated and identified as Neurospora crassa S1, which is able to produce cellulases using EFB as the sole carbon source. The strain started to secret cellulases into the medium after 24 h of cultivation at 30°C and reached its maximal cellulase activity at 240 h. Mass spectroscopy (MS) analysis showed that more than 50 proteins were secreted into the medium when EFB was used as the sole carbon source. Among them, 7 proteins were identified as putative enzymes associated with cellulose degradation. The whole cell culture of Neurospora crassa S1 was used to hydrolyze acid-treated EFB, giving a total sugar yield of 83.2%, which is comparable with that (82.0%) using a well-known cellulase producer Trichoderma reesei RUT-C30 (ATCC56765). CONCLUSION: Neurospora crassa S1 is a commercially promising native cellulase producer for EFB hydrolysis especially when the sugars obtained are to be fermented to products that require use of non-genetically engineered strains.


Assuntos
Celulases , Proteínas Fúngicas , Lignina/metabolismo , Neurospora crassa , Óleos de Plantas , Celulases/química , Celulases/isolamento & purificação , Celulases/metabolismo , Frutas/microbiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Neurospora crassa/enzimologia , Neurospora crassa/crescimento & desenvolvimento , Neurospora crassa/isolamento & purificação , Óleo de Palmeira
20.
Yao Xue Xue Bao ; 49(5): 701-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25151744

RESUMO

In the face of escalating problems with pathogen control, the development of proper formulations of existing antibiotics is as important as the development of novel antibiotics. Daptomycin is a lipopeptide antibiotic with potent activity against Gram-positive bacteria. Currently, only injectable solution of daptomycin has been approved for clinical use. In the present study, the formulation of PEGylated liposomal daptomycin (PLD) was prepared and optimized, and its efficacy against methicillin-resistant Staphylococcus aureus (MRSA252) strains was investigated. The obtained PLD had a mean vesicle diameter of (111.5 +/- 15.4) nm and a mean percent drug loading of (5.81 +/- 0.19) % with high storage stability. Potent activity of PLD against MRSA was demonstrated in vitro with a more sustained effect than that of conventional liposomal daptomycin and daptomycin solution. In addition, intravenous administration of a single dose (equal to human use) of PLD significantly increased the survival of mice in a MRSA252 systemic infection model compared with other formulations. Drug distribution in the lung was significantly enhanced following administration of PLD, and no measurable tissue lesions or pathological changes were detected during PLD treatment. Taken together, PEGylated liposomes loaded with daptomycin may represent a promising approach to reduce MRSA252 infections, especially those involving bloodstream dissemination, such as hematogenous pulmonary infection.


Assuntos
Antibacterianos/farmacologia , Daptomicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Animais , Lipossomos , Camundongos
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