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1.
Chem Rev ; 116(16): 9305-74, 2016 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-27459699

RESUMEN

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology-a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure-properties-application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistry, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Tecnología Química Verde , Madera/química , Celulosa/química , Equipos y Suministros Eléctricos , Hidrogeles , Dispositivos Laboratorio en un Chip , Lignina/química , Membranas Artificiales , Nanofibras/química , Papel , Polisacáridos/química , Porosidad , Energía Renovable
2.
Bioresour Technol ; 101(22): 8678-85, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20620049

RESUMEN

This study reports an ethanol yield of 270L/ton wood from lodgepole pine pretreated with sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) using an adapted strain, Saccharomyces cerevisiae Y5, without detoxification. The enzymatic hydrolysate produced from pretreated cellulosic solids substrate was combined with pretreatment hydrolysate before fermentation. Detoxification of the pretreatment hydrolysate using overliming or XAD-4 resin before being combined with enzymatic hydrolysate improved ethanol productivity in the first 4h of fermentation and overall fermentation efficiency. However, detoxification did not improve final ethanol yield because of sugar losses. The Y5 strain showed excellent ethanol productivities of 2.0 and 0.8g/L/h averaged over a period of 4 and 24h, respectively, in the undetoxified run. The furan metabolization rates of the Y5 strain were significantly higher for the undetoxified run than those for the detoxidfied runs, suggesting it can tolerate even higher furan concentrations than those studied. Preliminary mass and energy balances were conducted. SPORL produced an excellent monomeric sugar recovery value of about 85% theoretical and a net energy output of 4.05GJ/ton wood with an ethanol energy production efficiency of 178% before distillation.


Asunto(s)
Etanol/metabolismo , Lignina/metabolismo , Pinus/microbiología , Extractos Vegetales/metabolismo , Saccharomyces cerevisiae/metabolismo , Supervivencia Celular/efectos de los fármacos , Lignina/toxicidad , Pinus/química , Extractos Vegetales/química , Saccharomyces cerevisiae/efectos de los fármacos
3.
Bioresour Technol ; 101(9): 3106-14, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20061141

RESUMEN

The performance of two pretreatment methods, sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) and dilute acid (DA), was compared in pretreating softwood (spruce) for fuel ethanol production at 180 degrees Celsius for 30 min with a sulfuric acid loading of 5% on oven-dry wood and a 5:1 liquor-to-wood ratio. SPORL was supplemented with 9% sodium sulfite (w/w of wood). The recoveries of total saccharides (hexoses and pentoses) were 87.9% (SPORL) and 56.7% (DA), while those of cellulose were 92.5% (SPORL) and 77.7% (DA). The total of known inhibitors (furfural, 5-hydroxymethylfurfural, and formic, acetic and levulinic acids) formed in SPORL were only 35% of those formed in DA pretreatment. SPORL pretreatment dissolved approximately 32% of the lignin as lignosulfonate, which is a potential high-value co-product. With an enzyme loading of 15 FPU (filter paper units) per gram of cellulose, the cellulose-to-glucose conversion yields were 91% at 24h for the SPORL substrate and 55% at 48 h for the DA substrate, respectively.


Asunto(s)
Ácidos/farmacología , Biocombustibles , Biotecnología/métodos , Etanol/metabolismo , Lignina/metabolismo , Picea/efectos de los fármacos , Sulfitos/farmacología , Carbohidratos/análisis , Pared Celular/efectos de los fármacos , Celulasa/metabolismo , Fermentación/efectos de los fármacos , Glucosidasas/metabolismo , Hidrólisis/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Picea/citología , Polisacáridos/metabolismo , Soluciones , Factores de Tiempo , Viscosidad/efectos de los fármacos
4.
Cell Death Differ ; 16(9): 1289-99, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19373244

RESUMEN

Drugs with tumor selectivity may have an important benefit in chemotherapies. We have previously shown that Rocaglamide(s), derived from the medicinal plant Aglaia, kills various leukemic cells through the mitochondrial apoptosis pathway with only minor toxicities to normal lymphocytes. Here, we show further that Rocaglamide preferentially promotes activation-induced cell death in malignant T cells by differential regulation of c-FLIP and CD95L expression. Rocaglamide enhances and also prolongs activation-induced JNK activation in malignant T cells leading to downregulation of c-FLIP but upregulation of CD95L expression. We also show that malignant T cells express a significantly higher amount of Bid - the molecular linker that bridges the receptor-mediated to the mitochondria-mediated apoptosis pathway. Conversely, a substantially lower amount of c-FLIP in response to T-cell stimulation compared to normal T cells is observed. This difference may provide a therapeutic window for cancer treatment. The effect of Rocaglamide on sensitization of activation-induced cell death in malignant T cells was further demonstrated in vivo in a mouse model. Our study demonstrates that Rocaglamide may be a potential anticancer drug that simultaneously targets both c-FLIP and CD95L expressions in tumor cells. This study may also provide a new clue to design a more efficient chemotherapy by using a combination of stimuli that engage the receptor-mediated and the mitochondria-mediated death pathway.


Asunto(s)
Antineoplásicos/farmacología , Benzofuranos/farmacología , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/metabolismo , Proteína Ligando Fas/metabolismo , Leucemia de Células T/metabolismo , Animales , Apoptosis , Proteína Proapoptótica que Interacciona Mediante Dominios BH3/metabolismo , Línea Celular , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Células Jurkat , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Transducción de Señal , Linfocitos T/efectos de los fármacos , Trasplante Homólogo
5.
Water Sci Technol ; 54(9): 87-93, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17163046

RESUMEN

In recent years, considerable impetus emerges to develop strategies for reducing excess sludge produced in biological wastewater treatment (BWT) systems. In this study, an experiment on sludge reduction by ultrasound treatment was conducted. The influences of sonication on observed yield, sludge reduction, effluent quality, sludge settleability and stability were extensively evaluated. It was found that ultrasound had an impressive potential to reduce sludge production. Moreover, it was also concluded that a treatment time of 10 minutes was more cost-effective for sludge reduction, and a reduction by 44% was reached with an ultrasonic intensity of 0.25 w/ml. The reduction could be mainly attributed to disintegration of bio-flocs and cryptic growth. In addition, sonication time seemed to be more effective to reduce sludge production compared with ultrasonic intensity. Slight deterioration of the effluent quality and some variations of the sludge settleability and stability were observed after ultrasound treatment.


Asunto(s)
Aguas del Alcantarillado/química , Ultrasonido , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Amoníaco/análisis , Amoníaco/metabolismo , Infecciones Bacterianas/prevención & control , Nitrógeno/análisis , Nitrógeno/metabolismo , Oxígeno/análisis , Oxígeno/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Aguas del Alcantarillado/microbiología , Factores de Tiempo , Eliminación de Residuos Líquidos/economía , Purificación del Agua/economía
6.
Zhonghua Fu Chan Ke Za Zhi ; 29(11): 648-50, 697, 1994 Nov.
Artículo en Chino | MEDLINE | ID: mdl-7712882

RESUMEN

The clinical efficiency and mechanism of traditional Chinese medicinal herb Salvia Miltiorrhizae Bge (SMB) and Ligustrazine (L) on pregnancy induced hypertension (PIH) were studied in 30 patients. Before and after the administration of SMB and L, the following parameters: mean arterial pressure (MAP), proteinuria, levels of Thromboxane A2 (TXA2) and Prostacyclin (PGI2) were observed. TXA2 and PGI2 were measured by their stable hydration products Thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) by an established radioimmunoassay. The results of treatment were compared with the base line values and showed as follows: MAP and proteinuria decreased significantly (P < 0.05); no marked difference existed in TXB2; the level of 6-keto-PGF1 alpha increased significantly (P < 0.05); the rate of TXB2/6-keto-PGF1 alpha decreased significantly (P < 0.05). The results suggested that SMB and L can invigorate blood circulation by decreasing vasoconstriction.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Epoprostenol/sangre , Preeclampsia/tratamiento farmacológico , Pirazinas/uso terapéutico , Tromboxano A2/sangre , Adulto , Femenino , Humanos , Extractos Vegetales , Preeclampsia/sangre , Embarazo , Salvia miltiorrhiza
7.
Zhongguo Zhong Yao Za Zhi ; 18(8): 496-8, 511, 1993 Aug.
Artículo en Chino | MEDLINE | ID: mdl-8011099

RESUMEN

Experiment on the effect of extracts from Phyllanthus urinaria on HBsAg production in PLC/PRF/5 human hepatoma cell line showed that the production was decreased markedly 48 hours after the treatment of cells with 2-4 mg/ml Phyllanthus urinaria, especially in combination with 10(-5) mol/L of Ara-A. The decrease of extracellular HB-sAg excretion seems to stem from the inhibition of intracellular HBsAg formation.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Antígenos de Superficie de la Hepatitis B/biosíntesis , Vidarabina/farmacología , Carcinoma Hepatocelular/inmunología , Antígenos de Superficie de la Hepatitis B/efectos de los fármacos , Humanos , Neoplasias Hepáticas/inmunología , Células Tumorales Cultivadas/metabolismo
8.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 12(7): 421-3, 390, 1992 Jul.
Artículo en Chino | MEDLINE | ID: mdl-1392495

RESUMEN

In order to make a systematic study of the effect of Coptis chinensis on free radicals, the authors used the method that the drug and the brain homogenate of rat were mixed and incubated to investigate the effect of Coptis on lipid peroxidation. The result showed that the malondialdehyde (MDA) product of rat brain homogenate inhibited by 5% Coptis was significantly different from control (P < 0.001). On the basis of the above-mentioned results, the effect of Coptis on lipid peroxidation and diabetes of rats induced by alloxan was investigated. The result showed: (1) The MDA product of both pancreas and liver homogenate in Coptis group was significantly less than that in control and alloxan group (P < 0.01, P < 0.05). (2) Superoxide dismutases (SODs) in erythrocytes activity was the same for all groups (P > 0.50). (3) The blood catalase (CAT) activity in alloxan group markedly decreased compared with control group (P < 0.05), but no significant change between Coptis and alloxan group (P > 0.05). (4) The value of serum glucose in alloxan group was significantly increased in comparing with control group (P < 0.05). There was a trend to decrease the value of serum glucose in Coptis group compared with alloxan group, but no significant difference between two groups (P > 0.05). The experiment indicated that there was very strong inhibitory effect of Coptis to the lipid peroxidation in vitro and in vivo. Coptis could protect rat from diabetes inducing by alloxan and that probably was due to the fact that Coptis was able to inhibit alloxan inducing free radicals.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Medicamentos Herbarios Chinos/farmacología , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , Animales , Glucemia/metabolismo , Encéfalo/metabolismo , Catalasa/sangre , Diabetes Mellitus Experimental/enzimología , Masculino , Ratas , Ratas Wistar , Superóxido Dismutasa/sangre
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