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11.
12.
Effect of hemicellulose and lignin removal on enzymatic hydrolysis of steam pretreated corn stover 总被引:12,自引:0,他引:12
Ethanol can be produced from lignocellulosic biomass using steam pretreatment followed by enzymatic hydrolysis and fermentation. The sugar yields, from both hemicellulose and cellulose are critical parameters for an economically-feasible ethanol production process. This study shows that a near-theoretical glucose yield (96-104%) from acid-catalysed steam pretreated corn stover can be obtained if xylanases are used to supplement cellulases during hydrolysis. Xylanases hydrolyse residual hemicellulose, thereby improving the access of enzymes to cellulose. Under these conditions, xylose yields reached 70-74%. When pre-treatment severity was reduced by using autocatalysis instead of acid-catalysed steam pretreatment, xylose yields were increased to 80-86%. Partial delignification of pretreated material was also evaluated as a way to increase the overall sugar yield. The overall glucose yield increased slightly due to delignification but the overall xylose yield decreased due to hemicellulose loss in the delignification step. The data also demonstrate that steam pretreatment is a robust process: corn stover from Europe and North America showed only minor differences in behaviour. 相似文献
13.
Yingnan Si Seulhee Kim Eric Zhang Yawen Tang Renata Jaskula‐Sztul James M. Markert Herbert Chen Lufang Zhou Xiaoguang Liu 《Biotechnology journal》2020,15(1)
Exosomes hold great potential to deliver therapeutic reagents for cancer treatment due to its inherent low antigenicity. However, several technical barriers, such as low productivity and ineffective cancer targeting, need to be overcome before wide clinical applications. The present study aims at creating a new biomanufacturing platform of cancer‐targeted exosomes for drug delivery. Specifically, a scalable, robust, high‐yield, cell line based exosome production process is created in a stirred‐tank bioreactor, and an efficient surface tagging technique is developed to generate monoclonal antibody (mAb)‐exosomes. The in vitro characterization using transmission electron microscopy, NanoSight, and western blotting confirm the high quality of exosomes. Flow cytometry and confocal laser scanning microscopy demonstrate that mAb‐exosomes have strong surface binding to cancer cells. Furthermore, to validate the targeted drug delivery efficiency, romidepsin, a histone deacetylase inhibitor, is loaded into mAb‐exosomes. The in vitro anti‐cancer toxicity study shows high cytotoxicity of mAb‐exosome‐romidepsin to cancer cells. Finally, the in vivo study using tumor xenograft animal model validates the cancer targeting specificity, anti‐cancer efficacy, and drug delivery capability of the targeted exosomes. In summary, new techniques enabling targeted exosomes for drug delivery are developed to support large‐scale animal studies and to facilitate the translation from research to clinics. 相似文献
14.
Shu CW Madiraju C Zhai D Welsh K Diaz P Sergienko E Sano R Reed JC 《Journal of biomolecular screening》2011,16(2):174-182
Autophagy is an evolutionarily conserved process for catabolizing damaged proteins and organelles in a lysosome-dependent manner. Dysregulation of autophagy may cause various diseases, such as cancer and neurodegeneration. However, the relevance of autophagy to diseases remains controversial because of the limited availability of chemical modulators. Herein, the authors developed a fluorescence-based assay for measuring activity of the autophagy protease, autophagin-1(Atg4B). The assay employs a novel reporter substrate of Atg4B composed of a natural substrate (LC3B) fused to an assayable enzyme (PLA(2)) that becomes active upon cleavage by this cysteine protease. A high-throughput screening (HTS) assay was validated with excellent Z' factor (>0.7), remaining robust for more than 5 h and suitable for screening of large chemical libraries. The HTS assay was validated by performing pilot screens with 2 small collections of compounds enriched in bioactive molecules (n = 1280 for Lopac? and 2000 for Spectrum? library), yielding confirmed hit rates of 0.23% and 0.70%, respectively. As counterscreens, PLA(2) and caspase-3 assays were employed to eliminate nonspecific inhibitors. In conclusion, the LC3B-PLA(2) reporter assay provides a platform for compound library screening for identification and characterization of Atg4B-specific inhibitors that may be useful as tools for interrogating the role of autophagy in disease models. 相似文献
15.
Mary Henry Noêmi GalAn Katherine Teasdale Renata Prado Harpreet Amar Marina S. Rays Lesley Roberts Pedro Siqueira Gilles de Wildt Marcos Virmond Pranab K. Das 《PLoS neglected tropical diseases》2016,10(3)
BackgroundLeprosy is a leading cause of preventable disability worldwide. Delay in diagnosis of patients augments the transmission of infection, and allows progression of disease and more severe disability. Delays in diagnosis greater than ten years have been reported in Brazil. To reduce this delay, it is important to identify factors that hinder patients from presenting to doctors, and those that delay doctors from diagnosing patients once they have presented. This study aimed to explore factors associated with the delayed diagnosis of leprosy in Brazil.
Methodology/ Principal Findings
This is an exploratory study using a self-constructed questionnaire delivered to patients attending three leprosy referral clinics across three states in Brazil. Data were analysed to determine associations between variables and the time taken for participants to present to the health-service, and between variables and the time taken for doctors to diagnose participants once they had presented. Participants who suspected they had leprosy but feared community isolation were 10 times more likely to wait longer before consulting a doctor for their symptoms (OR 10.37, 95% CI 2.18–49.45, p = 0.003). Participants who thought their symptoms were not serious had a threefold greater chance of waiting longer before consulting than those who did (OR 3.114, 95% CI 1.235–7.856, p = 0.016). Forty-two point six per cent of participants reported initially receiving a diagnosis besides leprosy. These had a three times greater chance of receiving a later diagnosis of leprosy compared to those not misdiagnosed or not given a diagnosis (OR 2.867, 95% CI 1.288–6.384, p = 0.010).Conclusions/ Significance
This study implies a need for patient education regarding leprosy symptoms and the reduction of stigma to encourage patients to present. The high rate of misdiagnosis reported suggests a need to increase clinician suspicion of leprosy. Further education regarding disease symptoms in medical school curriculums may be advisable. 相似文献16.
Starch extruded in the presence of a plasticizer results in a material called thermoplastic starch (TPS). TPS mixed with poly(butylene adipate co-terephthalate) (PBAT), soybean oil (SO), and surfactant may result in films with improved mechanical properties due to greater hydrophobicity and compatibility among the polymers. This study characterized films produced from blends containing 65% TPS and 35% PBAT with SO added as compatibilizer. The Tween 80 was added to prevention of phase separation. The elongation and resistance were greater in the films with SO. The infrared spectra confirmed an increase in ester groups bonded to the PBAT and the presence of groups bonded to the starch ring, indicating TPS-SO and PBAT-SO interactions. The micrographs suggest that the films with SO were more homogenous. Thus, SO is considered to be a good compatibilizer for blends of TPS and PBAT. 相似文献
17.
Analysis of temperature‐mediated changes in the wine yeast Saccharomyces bayanus var uvarum. An oenological study of how the protein content influences wine quality 下载免费PDF全文
Eugenia Muñoz‐Bernal Michael J. Deery María Esther Rodríguez Jesús M. Cantoral Julie Howard Renata Feret Ramón Natera Kathryn S. Lilley Francisco Javier Fernández‐Acero 《Proteomics》2016,16(4):576-592
Saccharomyces bayanus var. uvarum plays an important role in the fermentation of red wine from the D.O. Ribera del Duero. This is due to the special organoleptic taste that this yeast gives the wines and their ability to ferment at low temperature. To determine the molecular factors involved in the fermentation process at low temperature, a differential proteomic approach was performed by using 2D‐DIGE, comparing, qualitatively and quantitatively, the profiles obtained at 13 and 25°C. A total of 152 protein spots were identified. We detected proteins upregulated at 13°C that were shown to be related to temperature stress, the production of aromatic compounds involved in the metabolism of amino acids, and the production of fusel alcohols and their derivatives, each of which is directly related to the quality of the wines. To check the temperature effects, an aromatic analysis by GC–MS was performed. The proteomic and “aromatomic” results are discussed in relation to the oenological properties of S. bayanus var. uvarum. 相似文献
18.
Marina Rovani Drummond Luciene Silva dos Santos Renata Soalheiro Fvaro Raquel Silveira Bello Stucchi Ilka de Ftima Santana Ferreira Boin Paulo Eduardo Neves Ferreira Velho 《PLoS neglected tropical diseases》2022,16(7)
BackgroundThis study aimed to assess the prevalence of Bartonella sp.-DNA detection in blood and skin samples from patients with non-viral end-stage liver disease awaiting liver transplantation.Methodology/Principal findingsBlood samples and healthy skin fragments from 50 patients were tested using microbiological and molecular methods. Fifteen patients had cryptogenic hepatitis (CH) and 35 had alcoholic, drug-induced or autoimmune liver disease. DNA was extracted from whole blood and liquid culture samples, isolates, and skin fragments. Thirteen of the 50 patients (26%) had Bartonella henselae DNA detection in their blood (9/50) and/or skin (5/50) samples. Colonies were isolated in 3/50 (6%) and infection was detected in 7/50 (14%) of the 50 patients. B. henselae-DNA detection was more prevalent in patients with CH than in other patients (p = 0.040). Of 39 patients followed-up for at least two years, a higher mortality rate was observed among patients with CH infected with B. henselae (p = 0.039).Conclusions/SignificanceFurther studies assessing the role of B. henselae infection in the pathogenesis of hepatitis patients must be urgently conducted. 相似文献
19.
Novel Keratinase from Bacillus subtilis S14 Exhibiting Remarkable Dehairing Capabilities 总被引:3,自引:0,他引:3 下载免费PDF全文
Alexandre J. Macedo Walter O. Beys da Silva Renata Gava David Driemeier Joo Antonio Pêgas Henriques Carlos Termignoni 《Applied microbiology》2005,71(1):594-596
We report the isolation of a keratinolytic-producing Bacillus subtilis strain and the characterization of the exceptional dehairing properties of its subtilisin-like keratinase. This enzyme can be an alternative to sodium sulfide, the major pollutant from tanneries, and may completely replace it. Its unique nonactivity upon collagen enhances its industrial potential. 相似文献
20.
Deciphering the molecular machinery of stem cells: a look at the neoblast gene expression profile 下载免费PDF全文
Rossi L Salvetti A Marincola FM Lena A Deri P Mannini L Batistoni R Wang E Gremigni V 《Genome biology》2007,8(4):R62