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1.
Molecules ; 29(11)2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38893495

RESUMEN

Muscadine grapes are characterized by their large and abundant seeds and hard and thick skins that contain significant amounts of dietary fiber (DF). The current study investigated the chemical constituents, molecular architecture, and physicochemical attributes of DF derived from Muscadine grapes (Granny Val and Alachua) and compared them with those derived from Shine Muscat and Kyoho. Using a combined enzymatic method, the total dietary fiber (TDF) was extracted and divided into two parts: soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). TDF (mainly IDF, with a small fraction of SDF) was dominated by cellulose, followed by pectin and hemicellulose. In addition, Granny Val and Alachua had a significantly higher abundance of TDF and IDF compared with Shine Muscat and Kyoho. Moreover, Shine Muscat had significantly the highest abundance of SDF among the four grape varieties. Of note, IDF from Granny Val and Alachua exhibited a complex and dense texture on its surface, and notably outperformed Shine Muscat and Kyoho in terms of cholesterol, fatty acid, heavy metal adsorption, and antioxidant activity. Collectively, Muscadine grapes, i.e., Granny Val and Alachua in the current study, possessed elevated DF levels (predominantly IDF), and their enhanced bioactivity underscored their potential as a potential food ingredient for further use.


Asunto(s)
Fibras de la Dieta , Vitis , Vitis/química , Fibras de la Dieta/análisis , Antioxidantes/química , Antioxidantes/análisis , Celulosa/química
2.
Molecules ; 28(17)2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37687090

RESUMEN

Rapeseed straw, bagasse, and walnut peel have a large amount of resource reserves, but there are few technologies for high value-added utilization. In the research of biochar, walnut green husk is rarely used as raw material. In addition, the three main components of biomass (lignin, cellulose, and hemicellulose) are present in similar proportions, and the differences between the physical and chemical properties of biochar prepared with similar amounts of biomass raw materials are not clear. Using three kinds of biomass of the same quality as raw materials, biochar was prepared via pyrolysis at 400 °C, and activated carbon was prepared via CO2 activation at 800 °C. The results showed that the pore numbers of the three kinds of biochar increased after activation, resulting in the increase of the specific surface area. The resulting numbers were 352.99 m2/g for sugarcane bagasse biochar (SBB)-CO2, 215.04 m2/g for rapeseed straw biochar (RSB)-CO2, and 15.53 m2/g for walnut green husk biochar (WGB)-CO2. Ash increased the amount of carbon formation, but a large amount of ash caused biochar to form a perforated structure and decreased the specific surface area (e.g., WGB), which affected adsorption ability. When the three main components were present in similar proportions, a high content of cellulose and lignin was beneficial to the preparation of biochar. The adsorption value of MB by biochar decreased with the increase of biomass ash content. After activation, the maximum adsorption value of MB for bagasse biochar was 178.17 mg/g, rapeseed straw biochar was 119.25 mg/g, and walnut peel biochar was 85.92 mg/g when the concentration of methene blue solution was 300 mg/L and the biochar input was 0.1 g/100 mL at room temperature. The adsorption of MB by biochar in solution occurs simultaneously with physical adsorption and chemical adsorption, with chemical adsorption being dominant. The optimal MB adsorption by SBB-CO2 was dominated by multimolecular-layer adsorption. This experiment provides a theoretical basis for the preparation of biochar and research on its applications in the future.


Asunto(s)
Brassica napus , Brassica rapa , Juglans , Saccharum , Celulosa , Lignina , Adsorción , Biomasa , Dióxido de Carbono , Carbón Orgánico , Azul de Metileno , Grano Comestible
3.
J Craniofac Surg ; 33(7): 2146-2153, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201701

RESUMEN

PURPOSE: Design an extended osteotomy guide (EOG) for Le Fort I osteotomy to improve the safety of surgery. MATERIALS AND METHODS: The digital Le Fort I osteotomy guide was designed in MIMICS 23.0. Twenty-eight patients were randomized into 2 groups. Patients in the experimental group used EOG, and patients in the control group used a traditional osteotomy guide (TOG). Virtual designs and actual postoperative outcomes were compared by cone-beam computed tomography. The safety of the operation was confirmed by the accuracy of the osteotomy direction and depth on the inner and posterior walls of the maxilla. RESULTS: All positioning deviations of both osteotomy guides were <0.3 mm (P>0.05). The osteotomy depths on the inner and posterior walls with the EOG and TOG deviated by 0.789±1.179 and 1.811±1.345 mm (P=0.004) and 0.648±0.999 and 1.262±0.942 mm (P=0.030), respectively. The angles of deviation of the osteotomy direction on the inner and posterior walls by the EOG and TOG were 2.025±2.434 and 5.069±2.391 degrees (P<0.001) and 2.772±2.979 and 8.653±4.690 degrees (P<0.001), respectively. CONCLUSIONS: The EOG was more accurate than TOG for manipulating osteotomy direction and depth on the inner and posterior maxillary walls. Thus, EOG could ensure higher surgical safety than TOG.


Asunto(s)
Maxilar , Osteotomía Maxilar , Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Equipo Ortopédico , Osteotomía Le Fort/métodos
4.
BMC Neurol ; 21(1): 402, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34666706

RESUMEN

BACKGROUND: Charcot-Marie-Tooth (CMT) disease is a group of inherited peripheral neuropathies, which are subdivided into demyelinating and axonal forms. Biallelic mutations in POLR3B are the well-established cause of hypomyelinating leukodystrophy, which is characterized by hypomyelination, hypodontia, and hypogonadotropic hypogonadism. To date, only one study has reported the demyelinating peripheral neuropathy phenotype caused by heterozygous POLR3B variants. CASE PRESENTATION: A 19-year-old male patient was referred to our hospital for progressive muscle weakness of the lower extremities. Physical examination showed muscle atrophy, sensory loss and deformities of the extremities. Nerve conduction studies and electromyography tests revealed sensorimotor demyelinating polyneuropathy with secondary axonal loss. Trio whole-exome sequencing revealed a de novo variant in POLR3B (c.3137G > A). CONCLUSIONS: In this study, we report the case of a Chinese patient with a de novo variant in POLR3B (c.3137G > A), who manifested demyelinating CMT phenotype without additional neurological or extra-neurological involvement. This work is the second report on POLR3B-related CMT.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Adulto , Enfermedad de Charcot-Marie-Tooth/genética , China , Heterocigoto , Humanos , Masculino , Mutación/genética , Fenotipo , ARN Polimerasa III , Adulto Joven
5.
Hepatobiliary Pancreat Dis Int ; 16(5): 470-479, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28992878

RESUMEN

BACKGROUND: The availability of novel direct-acting antivirals (DAAs) represents a new era of curative hepatitis C virus (HCV) treatment, with over 95% of patients infected with HCV genotype 1 achieving sustained virological response (SVR). Nevertheless, the majority of patients globally are unable to access these treatments because of cost and infrastructure constraints and, thus, remain untreated and uncured. DATA SOURCE: Relevant articles of peginterferon (PegIFN)-based treatments in HCV and sofosbuvir-based treatments, simeprevir, daclatasvir/asunaprevir, ritonavir-boosted paritaprevir/ombitasvir/dasabuvir, and grazoprevir/elbasvir, were searched in PubMed database, including general population and special population. RESULTS: PegIFN in combination with ribavirin remains an important and relevant option for some patients, achieving SVR rates of up to 79% in genotype 1 and 89% in genotype 2 or 3 infections, which increases for patients with favorable IL28B genotypes. Triple therapy of DAA plus PegIFN/ribavirin is effective in treating difficult-to-cure patients infected with HCV genotype 3 or with resistance-associated variants. Owing to its long history in HCV management, the efficacy, tolerability and long-term outcomes associated with PegIFN alfa-2a are well established and have been validated in large-scale studies and in clinical practice for many populations. Furthermore, emerging data show that IFN-induced SVR is associated with lower incidences of hepatocellular carcinoma compared with DAAs. On the contrary, novel DAAs have yet to be studied in special populations, and long-term outcomes, particularly tumor development and recurrence in patients with cirrhosis and/or hepatocellular carcinoma, and reactivation of HBV in dually infected patients, are still unclear. CONCLUSION: In this interferon-free era, PegIFN-based regimens remain a safe and effective option for selected HCV patients.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Coinfección/tratamiento farmacológico , Hepatitis B/tratamiento farmacológico , Humanos , Interferón-alfa/farmacocinética , Fallo Renal Crónico/metabolismo , Polietilenglicoles/farmacocinética , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapéutico
6.
J Oral Maxillofac Surg ; 74(11): 2286.e1-2286.e11, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27542550

RESUMEN

PURPOSE: To evaluate transverse displacement of the proximal segment after bilateral sagittal split ramus osteotomy (BSSO) advancement with different lingual split patterns and advancement amounts and to determine the influential factors related to mandibular width. MATERIALS AND METHODS: A 3-dimensional finite element model of the mandible including the temporomandibular joint was created for a presurgical simulation and for BSSO with lingual split patterns I (T1; Hunsuck split) and II (T2; Obwegeser split). The mandible was advanced 3 mm (A3) and 8 mm (A8) and fixated with a conventional titanium plate. Ansys software was used to measure the linear distances of the interproximal segments and to analyze the transverse displacement distribution of proximal segments after applying the load of masticatory muscle force groups. RESULTS: After surgical simulation, T1A3, T1A8, T2A3, and T2A8 showed increased transverse widths (mean, 2.99, 4.70, 2.36, and 4.42 mm, respectively). For transverse augmentation, there was a statistically significant difference between the 2 different mandibular advancement amounts in T1 and in T2 (P ≤ .000), but no significant differences was observed between T1 and T2 (P ≥ .058). The maximum transverse displacement distribution in the proximal segment was measured around the gonial area, and the early contact area was found near the border between the horizontal and sagittal osteotomy lines. CONCLUSION: Transverse displacements of proximal segments occur after BSSO advancement with T1 and T2 and transverse augmentation has statistically meaningful effects depending on the amount of advancement; however, no differences in transverse augmentation between T1 and T2 were identified. The fulcrum caused by the early contact between the proximal and distal segments could be an influential factor related to mandibular width.


Asunto(s)
Mandíbula/anatomía & histología , Mandíbula/cirugía , Avance Mandibular/métodos , Osteotomía Sagital de Rama Mandibular/métodos , Simulación por Computador , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Mandíbula/diagnóstico por imagen , Modelos Anatómicos , Evaluación de Resultado en la Atención de Salud , Periodo Preoperatorio
7.
J Oral Maxillofac Surg ; 73(5): 985-93, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25883003

RESUMEN

PURPOSE: To evaluate the split patterns of the mandibular ramus in sagittal split ramus osteotomy (SSRO) using cone-beam computed tomography (CBCT) and examine the related anatomic features that may be associated with these split patterns. PATIENTS AND METHODS: The authors designed and implemented a retrospective cohort study and enrolled a sample composed of consecutive patients with different maxillofacial deformities who underwent an SSRO from July 2011 through October 2012 at the Department of Orthognathic Surgery at the Tianjin Stomatological Hospital of Nankai University. The split patterns, which were selected at random at 1 side per patient, were evaluated by CBCT as the outcome variable 1 month after the operation. The predictor variable was composed of a set of heterogeneous anatomic variables that could be associated with the split patterns. Type I split was defined as a split at the lingual side near the mylohyoid sulcus. Type II split was defined as a split at the posterior border of the mandibular ramus. Appropriate bivariate and regression statistics were computed, and the level of statistical significance was set at a P value less than .05. RESULTS: One hundred thirty patients with different maxillofacial deformities (62 male and 68 female; mean age, 23 yr) underwent an SSRO. Two types of split patterns of the mandibular ramus were observed in SSRO: a split at the lingual side near the mylohyoid sulcus, which occurred in 75.38% of patients, and split at the posterior border region of the mandibular ramus, which occurred in 24.62% of patients. No fracture lines were observed through the mandibular canal. The thickness of the lingual cortical bone between the mandibular canal and the posterior border of the ramus was significantly associated with the split patterns (P < .05). The thickness of the cortical bone in the posterior border of the ramus, the degree of the mandibular angle, and the shapes of the mandibular ramus in the axial plane also were found to influence these split patterns. There was no meaningful association between the split patterns and a patient's age and gender. CONCLUSION: The split patterns of the mandibular ramus during SSRO were influenced by some anatomic features of the mandibular ramus. Therefore, examining the anatomy of the mandible with CBCT before surgery may play an important role in predicting the split patterns of the mandibular ramus during SSRO.


Asunto(s)
Mandíbula/cirugía , Anomalías Maxilofaciales/diagnóstico por imagen , Osteotomía Sagital de Rama Mandibular , Adulto , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Estudios Retrospectivos , Adulto Joven
8.
Science ; 381(6654): 216-221, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37440632

RESUMEN

The domestication of forest trees for a more sustainable fiber bioeconomy has long been hindered by the complexity and plasticity of lignin, a biopolymer in wood that is recalcitrant to chemical and enzymatic degradation. Here, we show that multiplex CRISPR editing enables precise woody feedstock design for combinatorial improvement of lignin composition and wood properties. By assessing every possible combination of 69,123 multigenic editing strategies for 21 lignin biosynthesis genes, we deduced seven different genome editing strategies targeting the concurrent alteration of up to six genes and produced 174 edited poplar variants. CRISPR editing increased the wood carbohydrate-to-lignin ratio up to 228% that of wild type, leading to more-efficient fiber pulping. The edited wood alleviates a major fiber-production bottleneck regardless of changes in tree growth rate and could bring unprecedented operational efficiencies, bioeconomic opportunities, and environmental benefits.


Asunto(s)
Edición Génica , Lignina , Populus , Madera , Carbohidratos/análisis , Lignina/genética , Madera/genética , Sistemas CRISPR-Cas , Populus/genética , Papel , Crecimiento Sostenible
9.
Biotechnol Bioeng ; 109(5): 1131-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22125215

RESUMEN

Multi-stage and single-stage enzymatic hydrolysis of cellulose (Avicel PH-101) were conducted to investigate individual factors that affect the rate-reducing kinetics of enzymatic hydrolysis. Understanding factors affecting enzymatic hydrolysis of Avicel will help improve hydrolysis of various biomasses. Product inhibition, enzyme deactivation, and the changes of substrate are potential factors that can affect the hydrolysis efficiency of Avicel. Multi-stage enzymatic hydrolysis resulted in 36.9% and 25.4% higher carbohydrate conversion as compared to a single-stage enzymatic hydrolysis with an enzyme loading of 5 and 20 FPU/g in a 96 h reaction. However, a decline in carbohydrate conversion of 1.6% and 2.6% was observed through each stage with 5 and 20 FPU/g, respectively. This indicated that the substrate became more recalcitrant as hydrolysis progressed. The decreased reactivity was not due to crystallinity because no significant change in crystallinity was detected by X-ray diffraction. Product inhibition was significant at low enzyme loading, while it was marginal at high enzyme loading. Therefore, product inhibition can only partially explain this decreased conversion. Another important factor, enzyme deactivation, contributed to 20.3% and 25.4% decrease in the total carbohydrate conversion of 96 h hydrolysis with 5 and 20 FPU/g, respectively. This work shows that an important reason for the decreased Avicel digestibility is the effect of enzyme blockage, which refers to the enzymes that irreversibly adsorb on accessible sites of substrate. About 45.3% and 63.2% of the total decreased conversion at the end of the 8th stage with 5 and 20 FPU/g, respectively, was due to the presence of irreversibly adsorbed enzymes. This blockage of active sites by enzymes has been speculated by other researchers, but this article shows further evidence of this effect.


Asunto(s)
Celulasas/metabolismo , Celulosa/metabolismo , Inhibidores Enzimáticos/metabolismo , Hidrólisis , Cinética
10.
J Craniofac Surg ; 23(2): 464-71, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22421870

RESUMEN

BACKGROUND: The technique of transsutural distraction osteogenesis (TSDO) rendered a new and minimally invasive alternative for midfacial advancement. Many topics addressed the osteotomy distraction of the midface; we know less, however, about the destiny of the advanced midface by transsutural distraction. METHODS: Long-term results of 20 patients with midfacial hypoplasia treated by either TSDO or osteotomy distraction osteogenesis (ODO) were investigated clinically, cephalometrically, and statistically. The follow-up period ranged from 4 to 10 years, and radiographic analysis, inpatient duration, whole length of treatment, times of outpatient treatment, and surgical morbidity were assessed. RESULTS: Nine patients were treated by the technique of TSDO, with a mean follow-up of 5.2 years (range, 4-8 years), and 11 by Le Fort III osteotomy distraction, with a mean follow-up of 6.4 years (range, 4-10 years). In TSDO group, the mean angle of SNA was 74.4 degrees preoperatively, 81.6 degrees immediately after distraction, 81.7 degrees at 6 months postoperatively, and 81.8 degrees in 4- to 8-year postoperative period. In ODO group, the mean angle of SNA was 74.0 degrees preoperatively, 85.3 degrees immediately after distraction, 83.2 degrees at 6 months postoperatively, and 83.1 degrees in 4- to 10-year postoperative period. In TSDO group, the mean advancement of anterior nasal spine-pterygomaxillary fissure length was 5.5 mm immediately after distraction, 0.03 mm at 6 months postoperatively, and 0.4 mm in 4- to 8-year postoperative period, resulting in no statistically significant retrusion; in ODO group, the mean advancement of anterior nasal spinepterygomaxillary fissure length was 12.2 mm immediately after distraction, which decreased 2.5 mm at 6 months postoperatively and 2.5 mm in 4- to 10-year postoperative period, resulting in retrusion rate of about 20%. The patients in ODO group had longer inpatient duration, and 1 patient had an inharmonious forward movement manifested nasal root prominence and medial canthal alteration. Those in group TSDO had a longer process of treatment and more times of outpatient manipulation. CONCLUSIONS: The technique of TSDO is effective, minimally invasive, and aesthetically optimal for early correction of midfacial hypoplasia of the growing children, and the technique of ODO can be used successfully for hypoplastic midface of the adults. The most postoperative retrusion appeared in the first 6 months, and no statistically significant retrusion occurred in growing patients.


Asunto(s)
Suturas Craneales/cirugía , Disostosis Craneofacial/cirugía , Osteogénesis por Distracción/métodos , Osteotomía Le Fort/métodos , Cefalometría , Niño , Preescolar , Femenino , Humanos , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos , Resultado del Tratamiento
11.
Chem Commun (Camb) ; 58(82): 11547-11550, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36156662

RESUMEN

Two kinds of AIE-active fluorescent organic nanoparticles were designed and constructed as anti-counterfeiting photoresponsive materials. One is fluorescent organic nanoparticles (TPELs) based on a self-assembly strategy, which were self-assembled from novel amphiphilic tetraphenylethylene (TPE) molecules decorated with a lactose moiety and different photoresponsive tags. The other is polymeric fluorescent organic nanoparticles (F-TPEs) derived from the nanoprecipitation strategy, which utilized pluronic copolymer F127 to encapsulate hydrophobic TPEs without lactosyl modifications. Upon UV light irradiation, these AIE-active materials exhibit different photooxidation behaviors in an aqueous solution to give cyan, orange and green fluorescence emissions, and they were successfully used as an anti-counterfeiting fluorescent hydrogel and ink.


Asunto(s)
Tinta , Nanopartículas , Excipientes , Colorantes Fluorescentes/química , Hidrogeles , Lactosa , Nanopartículas/química , Poloxámero/química , Polímeros/química
12.
Planta ; 233(6): 1097-110, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21298285

RESUMEN

A quantitative approach to characterize lignin-carbohydrate complex (LCC) linkages using a combination of quantitative ¹³C NMR and HSQC 2D NMR techniques has been developed. Crude milled wood lignin (MWLc), LCC extracted from MWLc with acetic acid (LCC-AcOH) and cellulolytic enzyme lignin (CEL) preparations were isolated from loblolly pine (Pinus taeda) and white birch (Betula pendula) woods and characterized using this methodology on a routine 300 MHz NMR spectrometer and on a 950 MHz spectrometer equipped with a cryogenic probe. Structural variations in the pine and birch LCC preparations of different types (MWL, CEL and LCC-AcOH) were elucidated. The use of the high field NMR spectrometer equipped with the cryogenic probe resulted in a remarkable improvement in the resolution of the LCC signals and, therefore, is of primary importance for an accurate quantification of LCC linkages. The preparations investigated showed the presence of different amounts of benzyl ether, γ-ester and phenyl glycoside LCC bonds. Benzyl ester moieties were not detected. Pine LCC-AcOH and birch MWLc preparations were preferable for the analysis of phenyl glycoside and ester LCC linkages in pine and birch, correspondingly, whereas CEL preparations were the best to study benzyl ether LCC structures. The data obtained indicate that pinewood contains higher amounts of benzyl ether LCC linkages, but lower amounts of phenyl glycoside and γ-ester LCC moieties as compared to birch wood.


Asunto(s)
Betula/química , Carbohidratos/química , Lignina/química , Pinus taeda/química , Betula/metabolismo , Conformación de Carbohidratos , Metabolismo de los Hidratos de Carbono , Lignina/metabolismo , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular/métodos , Pinus taeda/metabolismo , Madera/química
13.
Biomed Res Int ; 2020: 2430640, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32149091

RESUMEN

Enterovirus 71 (EV71) is the causative pathogen of hand, foot, and mouth disease (HFMD). However, no effective antiviral therapy is currently available. Some viruses could escape the host's innate immunity by upregulating suppressor of cytokine signaling (SOCS) proteins. Until now, whether EV71 evades the host immune system by regulating the expression of SOCS proteins remains unknown. In this study, we found that EV71 infection promoted SOCS expression at both mRNA and protein levels in vitro and in vivo. Consistently, the infectivity of EV71 was decreased significantly in the SOCS3 or SOCS1 knockdown cells, suggesting that SOCS1 and especially SOCS3 are crucial for EV71 infection. Further investigation showed that SOCS3 promoted virus infection by inhibiting interferon-induced STAT3 phosphorylation. SOCS1 and SOCS3 mRNA expressions were independent on virus-induced type I interferon expression but were blocked by the inhibitor of NF-κB. Therefore, EV71 infection stimulates the expression of SOCS proteins in an interferon-independent way and negatively regulates the JAK/STAT signaling pathway, thus escaping host immunity. All these results may add new information to the mechanism of EV71 in fighting against type I interferon responses.


Asunto(s)
Infecciones por Enterovirus/metabolismo , Enterovirus/efectos de los fármacos , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/farmacología , Replicación Viral/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Infecciones por Enterovirus/inmunología , Inmunidad Innata/inmunología , Interferón Tipo I/metabolismo , Ratones , Ratones Noqueados , FN-kappa B/metabolismo , ARN Mensajero , Receptor de Interferón alfa y beta/genética , Proteína 1 Supresora de la Señalización de Citocinas , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Regulación hacia Arriba
14.
Bioresour Technol ; 269: 346-354, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30195227

RESUMEN

In this study, a novel modified nickel/H-beta (Ni/DeAl-beta) catalyst, which has active acidic sites and hydrogen binding sites, was prepared and used to produce liquefied fuel from lignin. The bifunctional Ni/DeAl-beta catalyst efficiently converted kraft lignin into liquefied fuel due to the synergistic effect of aluminum Lewis acid sites and nickel hydrogen binding sites. At a nickel content of 0.6 mmol/gzeolite, the Ni/DeAl-beta catalyst gave a high liquid product yield of 88.6% at 300 °C for 36 h. Most of the liquid product was dissolved in petroleum ether (73% of 88.6%), which was mainly composed of monomeric and dimeric degradation products. Under these conditions, the higher heating values (HHV) increased from 24.9 MJ/kg for kraft lignin to 32.0 MJ/kg for the liquid product. These results demonstrated the bifunctional Ni/DeAl-beta catalyst could be an efficient catalyst for lignin to liquefied fuel conversion.


Asunto(s)
Biocombustibles , Lignina/química , Níquel , Catálisis , Polimerizacion
15.
Nat Commun ; 9(1): 1579, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29679008

RESUMEN

A multi-omics quantitative integrative analysis of lignin biosynthesis can advance the strategic engineering of wood for timber, pulp, and biofuels. Lignin is polymerized from three monomers (monolignols) produced by a grid-like pathway. The pathway in wood formation of Populus trichocarpa has at least 21 genes, encoding enzymes that mediate 37 reactions on 24 metabolites, leading to lignin and affecting wood properties. We perturb these 21 pathway genes and integrate transcriptomic, proteomic, fluxomic and phenomic data from 221 lines selected from ~2000 transgenics (6-month-old). The integrative analysis estimates how changing expression of pathway gene or gene combination affects protein abundance, metabolic-flux, metabolite concentrations, and 25 wood traits, including lignin, tree-growth, density, strength, and saccharification. The analysis then predicts improvements in any of these 25 traits individually or in combinations, through engineering expression of specific monolignol genes. The analysis may lead to greater understanding of other pathways for improved growth and adaptation.


Asunto(s)
Lignina/biosíntesis , Lignina/genética , Populus/genética , Madera/química , Madera/fisiología , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/genética , Populus/metabolismo , Transcriptoma/genética , Árboles/genética , Árboles/metabolismo , Xilema/metabolismo
16.
J Ocul Pharmacol Ther ; 33(2): 103-110, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28106491

RESUMEN

PURPOSE: To design an MG132-sustained drug delivery capsular ring (SDDCR) and investigate its effect on the inhibition of posterior capsule opacification (PCO) in a rabbit model. METHODS: The SDDCRs were prepared by forming a slice of film made by the mixture of poly lactic-co-glycolic acid (PLGA) and MG132 on the surface of capsular tension rings (CTRs). The drug-loading capacity, entrapment efficiency, and in vitro release of the drug-containing film were detected. Eighteen New Zealand white rabbits were operated with phacoemulsification and MG132-SDDCRs/PLGA-CTRs/CTRs implantation in the single eye. The images of the anterior segments were acquired at certain days, and the epithelial-mesenchymal transition (EMT) markers were detected by western blot and immunofluorescence. RESULTS: The drug-loading capacity and entrapment efficiency of MG132-SDDCRs were 1.15% ± 0.04% and 66.16% ± 0.027%, respectively, and the drug released well within a month. The PCO degree of the MG132-SDDCR group was significantly lower than the other groups. The expression of alpha-smooth muscle actin, fibronectin, vimentin, and collagen-I was lower, and the expression of E-cadherin (E-cad) was higher in the MG132-SDDCR group than the other groups. CONCLUSIONS: MG132-SDDCRs could be established successfully. The PCO process was prevented, and the expression of EMT markers was inhibited by the implantation of MG132-SDDCRs, indicating that this could be a potential treatment against PCO.


Asunto(s)
Opacificación Capsular/tratamiento farmacológico , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Ácido Láctico/farmacología , Leupeptinas/farmacología , Ácido Poliglicólico/farmacología , Cápsula Posterior del Cristalino/efectos de los fármacos , Animales , Ácido Láctico/administración & dosificación , Leupeptinas/administración & dosificación , Ácido Poliglicólico/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Conejos
17.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(3): 306-312, 2017 03 15.
Artículo en Zh | MEDLINE | ID: mdl-29806259

RESUMEN

Objective: To extend its application in the field of bone repair by adding oxygen-carboxymethylated chitosan (O-CMC) and gentamicin for modification of the calcium sulfate cement (CSC). Methods: The O-CMC/CSC was prepared by adding O-CMC with different concentrations (0.1wt%, 0.3wt%, 0.5wt%, 0.7wt%, and 1.0wt%) in the CSC liquid phase. The effect of O-CMC on the CSC was evaluated by testing the injectability, compressive strength, degradation rate, pH value, cytotoxicity and osteogenesis. After the optimal concentration of O-CMC was determined, gentamicin with different concentrations (0.5wt%, 1.5wt%, and 2.5wt%) was added in the O-CMC/CSC, and then the compressive strength and antibacterial properties were investigated. Results: After adding O-CMC in the CSC liquid phase, the injection time of O-CMC/CSC was increased to more than 5 minutes; it significantly prolonged with increased concentration of O-CMC ( P<0.05). The compressive strength of the modified bone cement was in the range of 11-18 MPa and it was the highest when the concentration of O-CMC was 0.5wt% ( P<0.05). The degradation rate of O-CMC/CSC was not influenced obviously by O-CMC ( P>0.05). The pH value was in the range of 7.2-7.4 and Ca 2+ concentration was in the range of 6-8 mmol/L. In vitro mineralization experiment indicated that the induced mineralization ability of O-CMC/CSC was much higher than that of pure CSC. The 0.5wt% O-CMC/CSC had the best performance; the compressive strength of the composite bone cement was above 5 MPa after gentamicin was added, which had antibacterial effect. Conclusion: O-CMC is able to effectively improve the injection, compressive strength, and osteogenic activity of CSC; in addition, antibacterial properties is obtained in the CSC after adding gentamicin.


Asunto(s)
Cementos para Huesos , Sulfato de Calcio , Quitosano , Gentamicinas , Fuerza Compresiva , Ensayo de Materiales , Oxígeno
18.
Bioresour Technol ; 241: 857-867, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28629103

RESUMEN

A biologically-based lignocellulosic biorefinery process for obtaining carbohydrates from raw biomass was investigated across six diverse biomasses (three hardwoods & three nonwoods) for the purpose of decoding lignin's influence on sugar production. Acknowledging that lignin could positively alter the economics of an entire process if valorized appropriately, we sought to correlate the chemical properties of lignin within the process to the traditional metrics associated with carbohydrate production-cellulolytic digestibility and total sugar recovery. Based on raw carbohydrate, enzymatic recovery ranged from 40 to 64% w/w and total recovery ranged from 70 to 87% w/w. Using nitrobenzene oxidation to quantify non-condensed lignin structures, it was found that raw hardwoods bearing increasing non-condensed S/V ratios (2.5-5.1) render increasing total carbohydrate recovery from hardwood biomasses. This finding indicates that the chemical structure of hardwood lignin influences the investigated biorefinery process' ability to generate carbohydrates from a given raw hardwood feedstock.


Asunto(s)
Reactores Biológicos , Carbohidratos , Lignina , Biomasa , Hidrólisis , Oxidación-Reducción
19.
Bioresour Technol ; 243: 100-106, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28651130

RESUMEN

In this study, a novel catalyst, S2O82--KNO3/TiO2, which has active acidic and basic sites, was prepared and used in lignin hydrocracking with a co-catalyst, Ru/C. Ru/C is an efficient hydrogenation catalyst and S2O82--KNO3/TiO2 is a dual catalyst, which could efficiently degrade lignin. This catalytic hydrogenation system can reduce solid products to less than 1%, while giving a high liquid product yield of 93%. Catalytic hydrocracking of kraft lignin at 320°C for 6h gave 93% liquid product with 0.5% solid product. Most of this liquid product was soluble in petroleum ether (60% of 93%), which is a clear liquid and comprises mainly of monomeric and dimeric degradation products. These results demonstrated that the combination of the two catalysts is an efficient catalyst for liquefaction of lignin, with little char formation (∼1%). This concept has the potential to produce valuable chemicals and fuels from lignin under moderate conditions.


Asunto(s)
Catálisis , Lignina , Hidrogenación , Solventes
20.
Sci Rep ; 6: 20839, 2016 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-26861413

RESUMEN

Coxsackievirus A16 (CA16) and enterovirus 71 (EV71) are two main causative pathogens of hand, foot and mouth disease (HFMD). Unlike EV71, virulence determinants of CA16, particularly within 5' untranslated region (5'UTR), have not been investigated until now. Here, a series of nucleotides present in 5'UTR of lethal but not in non-lethal CA16 strains were screened by aligning nucleotide sequences of lethal circulating Changchun CA16 and the prototype G10 as well as non-lethal SHZH05 strains. A representative infectious clone based on a lethal Changchun024 sequence and infectious mutants with various nucleotide alterations in 5'UTR were constructed and further investigated by assessing virus replication in vitro and virulence in neonatal mice. Compared to the lethal infectious clone, the M2 mutant with a change from cytosine to uracil at nucleotide 104 showed weaker virulence and lower replication capacity. The predicted secondary structure of the 5'UTR of CA16 RNA showed that M2 mutant located between the cloverleaf and stem-loop II, affected interactions between the 5'UTR and the heterogeneous nuclear ribonucleoprotein K (hnRNP K) and A1 (hnRNP A1) that are important for translational activity. Thus, our research determined a virulence-associated site in the 5'UTR of CA16, providing a crucial molecular target for antiviral drug development.


Asunto(s)
Regiones no Traducidas 5' , Infecciones por Coxsackievirus/virología , Enterovirus/genética , Enterovirus/patogenicidad , Replicación Viral , Animales , Animales Recién Nacidos , Secuencia de Bases , Infecciones por Coxsackievirus/mortalidad , Modelos Animales de Enfermedad , Ribonucleoproteína Nuclear Heterogénea A1 , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Ratones , Morbilidad , Mortalidad , Mutación , Conformación de Ácido Nucleico , ARN Viral/química , ARN Viral/genética , Análisis de Secuencia de ADN , Virulencia/genética
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