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1.
Elif Erdem Ibrahim Inan Harbiyeli Hazal Boral Macit Ilkit Meltem Yagmur Reha Ersoz 《Mycopathologia》2018,183(3):521-527
Purpose
To evaluate the efficiency of corneal collagen cross-linking (CXL) in addition to topical voriconazole in cases with mycotic keratitis.Design
Retrospective case series in a tertiary university hospital.Participants
CXL was performed on 13 patients with mycotic keratitis who presented poor or no response to topical voriconazole treatment.Methods
The clinical features, symptoms, treatment results and complications were recorded retrospectively. The corneal infection was graded according to the depth of infection into the stroma (from grade 1 to grade 3). The visual analogue scale was used to calculate the pain score before and 2 days after surgery.Main Outcome Measures
Grade of the corneal infection.Results
Mean age of 13 patients (6 female and 7 male) was 42.4 ± 17.7 years (20–74 years). Fungus was demonstrated in culture (eight patients) or cytological examination (five patients). Seven of the 13 patients (54%) were healed with topical voriconazole and CXL adjuvant treatment in 26 ± 10 days (15–40 days). The remaining six patients did not respond to CXL treatment; they initially presented with higher grade ulcers. Pre- and post-operative pain score values were 8 ± 0.8 and 3.5 ± 1, respectively (p < 0.05).Conclusions
The current study suggests that adjunctive CXL treatment is effective in patients with small and superficial mycotic ulcers. These observations require further research by large randomized clinical trials.2.
Wenguang Zhang Dongmei Liu Jianzhuang Ren Pengli Zhou Xinwei Han 《Biotechnology letters》2018,40(2):271-278
Objectives
To investigate the potential role and underlying mechanism of Sirtuin2 (SIRT2) in regulating high glucose (HG)-induced vascular endothelial cell injury by using human umbilical vein endothelial cells (HUVECs).Results
SIRT2 mRNA and protein expression levels were decreased in HG-treated HUVECs. SIRT2 overexpression increased viability, decreased apoptosis and reduced levels of reactive oxygen species in HG-treated HUVECs. SIRT2 overexpression decreased TNF-α expression (146.5 ± 22.8 pg TNF-α ml?1) relative to that in the empty vector group (263.5 ± 18.5 pg TNF-α ml?1) and decreased MCP-1 expression (63.8 ± 9.85 pg MCP-1 ml?1) relative to that in the empty vector group (105.8 ± 8.5 pg MCP-1 ml?1). SIRT2 overexpression decreased the acetylation of p53 by 33% and decreased the acetylation of NF-κB p65 by 58% in HG-treated HUVECs.Conclusion
SIRT2 prevents HG-induced vascular endothelial cell injury through suppressing the p53 and NF-κB signaling pathways.3.
Objective
To re-engineer the active site of proteins for non-natural substrates using a position-based prediction method (PBPM).Results
The approach has been applied to re-engineer the E. coli glutamate dehydrogenase to alter its substrate from glutamate to homoserine for a de novo 1,3-propanediol biosynthetic pathway. After identification of key residues that determine the substrate specificity, residue K92 was selected as a candidate site for mutation. Among the three mutations (K92V, K92C, and K92M) suggested by PBPM, the specific activity of the best mutant (K92 V) was increased from 171 ± 35 to 1328 ± 71 μU mg?1.Conclusion
The PBPM approach has a high efficiency for re-engineering the substrate specificity of natural enzymes for new substrates.4.
Wenwen Zhang Zhaohui Chen Mengmeng Wu Zhong Shi Feng Zhu Guoqiang li Ting Ma 《Biotechnology letters》2016,38(6):991-997
Objective
To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs.Results
The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l?1 compared to 21 g ± 0.4 g l?1 in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties.Conclusions
Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.5.
Objectives
To investigate the contribution of direct electron transfer mechanisms to electricity production in microbial fuel cells by physically retaining Shewanella oneidensis cells close to or away from the anode electrode.Results
A maximum power output of 114 ± 6 mWm?2 was obtained when cells were retained close to the anode using a dialysis membrane. This was 3.5 times more than when the cells were separated away from the anode. Without the membrane the maximum power output was 129 ± 6 mWm?2. The direct mechanisms of electron transfer contributed significantly to overall electron transfer from S. oneidensis to electrodes, a result that was corroborated by another experiment where S. oneidensis cells were entrapped in alginate gels.Conclusion
S. oneidensis transfers electrons primarily by direct electron transfer as opposed to mediated electron transfer.6.
Ylva Gårdinger Anna Dieden Joanna Hlebowicz Ola Björgell Magnus Dencker 《Cardiovascular ultrasound》2017,15(1):10
Background
Myocardial performance index (MPI) has been investigated in a variety of populations, but the effect of food intake has not been evaluated. We assessed whether myocardial performance index is affected by food intake in healthy subjects.Methods
Twenty-three healthy subjects aged 25.6?±?4.5 years were investigated. MPI was measured before, 30 min after, and 110 min after a standardized meal.Results
MPI decreased significantly (P?<?0.05) from fasting values 30 min after the meal, and had almost returned to baseline after 110 min. MPI decreased from 0.28?±?0.06 (fasting) to 0.20?±?0.07 30 min after eating. At 110 min after eating the index value was almost back to the baseline value 0.26?±?0.06. (P?=?0.15).Conclusions
This study shows that myocardial performance index is affected by food intake in healthy subjects.7.
Junzhi Wang Cheng Zheng Tianyi Zhang Yingmiao Liu Zhuopei Cheng Dong Liu Hanjie Ying Huanqing Niu 《Biotechnology letters》2017,39(12):1875-1881
Objectives
To develop a new one-pot polyphosphate kinase (PPK) system with low cost and high efficiency for ATP regeneration in industrial CTP production.Results
We developed a new one-pot PPK system by applying a three-enzyme cascade (CMK, NDK and PPK) with an in vitro polyP-based ATP regeneration system. The PPK was selected from twenty sources, and was made solvable by fusion expressing with soluble protein and constructing polycistronic plasmids, or co-expressing with molecular chaperones GroES/EL. Activities of other enzymes were optimized by employing fusion expression, tac-pBAD system, Rosetta host and codon optimization. After 24 h, the concentration of CDP and CTP reached 3.8 ± 0.2 and 6.9 ± 0.3 mM l?1 respectively with a yield of approximately 79%. The molar conversion rate of CTP was 51%, and its yield and conversion rate increased 100% from the traditional system.Conclusions
A new one-pot ATP regeneration system applying polyphosphate kinase for CTP production was developed.8.
Objectives
To search for a novel glutamate decarboxylase (GAD) with an optimum pH towards near-neutrality in order to improve production of gamma-aminobutyric acid (GABA) in recombinant hosts.Results
A novel glutamate decarboxylase, BmGAD, from Bacillus megaterium was overexpressed and purified. BmGAD was approximately 53 kDa by SDS-PAGE analysis. Its optimum activity was at pH 5 and 50 °C. BmGAD had a specific activity of 59 ± 5.2 U mg?1 at pH 6, which is the highest value reported so far. The apparent Km and Vmax values of BmGAD were 8 ± 0.5 mM and 150 ± 4.7 U mg?1, respectively. Through site-directed mutagenesis, two BmGAD mutants (E294R and H467A) showed higher Vmax values than that of wild-type, with the values of 210 ± 6.9 and 180 ± 4.1 U mg?1 at pH 5 and 50 °C, respectively.Conclusions
The unusual high activity of BmGAD at pH 6 makes it an attractive GABA-producing candidate in industrial application.9.
Patrizia Aruta Denisa Muraru Andrada Camelia Guta Sorina Mihaila Niccolò Ruozi Chiara Palermo Basma Elnagar Sabino Iliceto Luigi P. Badano 《Cardiovascular ultrasound》2018,16(1):27
Background
Transcatheter mitral valve replacement (TMVR) is a new therapeutic option for high surgical risk patients with mitral regurgitation (MR). Mitral valve (MV) geometry quantification is of paramount importance for success of the procedure and transthoracic 3D echocardiography represents a useful screening tool. Accordingly, we sought to asses MV geometry in patients with functional MR (FMR) that would potentially benefit of TMVR, focusing on the comparison of mitral annulus (MA) geometry between patients with ischemic (IMR) and non ischemic mitral regurgitation (nIMR).Methods
We retrospectively selected 94 patients with severe FMR: 41 (43,6%) with IMR and 53 (56,4%) with nIMR. 3D MA analysis was performed on dedicated transthoracic 3D data sets using a new, commercially-available software package in two moments of the cardiac cycle (early-diastole and mid-systole). We measured MA dimension and geometry parameters, left atrial and left ventricular volumes.Results
Maximum (MA area 10.7?±?2.5 cm2 vs 11.6?±?2.7 cm2, p?>?0.05) and the best fit plane MA area (9.9?±?2.3 cm2 vs 10.7?±?2.5 cm2, p?>?0.05, respectively) were similar between IMR and nIMR. nIMR patients showed larger mid-systolic 3D area (9.8?±?2.3 cm2 vs 10.8?±?2.7 cm2, p?<?0.05) and perimeter (11.2?±?1.3 cm vs 11.8?±?1.5 cm, p?<?0.05) with longer and larger leaflets, and wider aorto-mitral angle (135?±?10° vs 141?±?11°, p?<?0.05). Conversely, the area of MA at the best fit plane did not differ between IMR and nIMR patients (9?±?1.1 cm2 vs 9.9?±?1.5 cm2, p?>?0.05).Conclusions
Patients with ischemic and non-ischemic etiology of FMR have similar maximum dimension, yet systolic differences between the two groups should be taken into account to tailor prosthesis’s selection.Trial registration
N.A.10.
F. A. Kortlandt C. C. van ’t Klooster A. L. M. Bakker M. J. Swaans J. C. Kelder T. L. de Kroon B. J. W. M. Rensing F. D. Eefting J. A. S. van der Heyden M. C. Post 《Netherlands heart journal》2016,24(7-8):475-480
Background
Surgical risk scores are used to identify high-risk patients for surgical mitral valve repair. There is no scoring system to estimate the mortality risk for patients undergoing percutaneous treatment. The aim of this analysis is to evaluate the predictive value of the EuroSCOREs and the Society of Thoracic Surgeons Predicted Risk of Mortality Score (STS) for periprocedural mortality in percutaneous edge-to-edge mitral valve repair.Methods
From 2009 to 2013, 136 high-risk patients were included who underwent 143 procedures. Observed periprocedural mortality was compared with predicted mortality using the logistic EuroSCORE, EuroSCORE II and STS. The predictive value was analysed by receiver operating characteristic curves for each score.Results
Observed periprocedural mortality was 3.5 %. The predicted surgical mortality risk was: 23.1 ± 15.7 % for the logistic EuroSCORE, 9.6 ± 7.7 % for the EuroSCORE II and 13.2 ± 8.2 % for the STS. The predictive value estimated by the area under the curve was: 0.55, 0.54 and 0.65 for the logistic EuroSCORE, EuroSCORE II and STS respectively. Severe pulmonary hypertension and acute procedural success were significant predictive parameters in univariate analysis.Conclusion
Contemporary surgical scores do not adequately predict periprocedural mortality for high-risk patients undergoing edge-to-edge mitral valve repair, but they can be used to help decision-making in the selection process for this procedure.11.
Objectives
Establish a method to indirectly measure evaporation in microwell-based cell culture systems and show that the proposed method allows compensating for liquid losses in fed-batch processes.Results
A correlation between evaporation and the concentration of Na+ was found (R2?=?0.95) when using the 24-well-based miniature bioreactor system (micro-Matrix) for a batch culture with GS-CHO. Based on these results, a method was developed to counteract evaporation with periodic water additions based on measurements of the Na+ concentration. Implementation of this method resulted in a reduction of the relative liquid loss after 15 days of a fed-batch cultivation from 36.7?±?6.7% without volume corrections to 6.9?±?6.5% with volume corrections.Conclusion
A procedure was established to indirectly measure evaporation through a correlation with the level of Na+ ions in solution and deriving a simple formula to account for liquid losses.12.
Dawei Zhu De-Bin Wang Tian-shun Song Ting Guo Pingkai Ouyang Jingjing Xie 《Biotechnology letters》2016,38(2):271-277
Objective
To demonstrate that an enhanced sediment microbial fuel cell (SMFC) system can accelerate the degradation of cellulose in fresh water sediments as the accumulation of cellulose in lake sediments may aggravate the lake marsh, increase organic matter content and result in rapid deterioration of water quality and damage the ecosystem.Results
After 330 days the highest cellulose removal efficiency (72.7 ± 2.1 %) was achieved in the presence of a SMFC with a carbon nanotube decorated cathode, followed by a SMFC without the cathode decoration (64.4 ± 2.8 %). The lowest cellulose removal efficiency (47.9 ± 2.1 %) was in the absence of SMFC. The sediment characterization analysis confirmed that the carbon nanotube decorated cathode enhances the electron transfer rate in the SMFC and improves the dissolved organic matter oxidation rate.Conclusion
This study offers a relatively simple and promising new method for cellulose degradation in sediment.13.
Objectives
To study the binding of pranlukast to hRKIP and its regulatory role in the Raf1/MEK/ERK signal pathway.Results
NMR and fluorescence experiments demonstrated hRKIP could bind pranlukast with a binding constant of 1016 mM?1. Residues (Y81, S109 and Y181) on the conserved ligand-binding pocket of hRKIP played a crucial role in binding pranlukast, and their mutations reduced the binding affinity more than 85 %. Furthermore, 25 μM pranlukast could up-regulate the ERK phosphorylation by about 17 %.Conclusion
Pranlukast may be used as a potential drug precursor for treating hRKIP involved diseases.14.
Opportunities for mobilizing recalcitrant phosphorus from agricultural soils: a review 总被引:3,自引:0,他引:3
Daniel Menezes-Blackburn Courtney Giles Tegan Darch Timothy S. George Martin Blackwell Marc Stutter Charles Shand David Lumsdon Patricia Cooper Renate Wendler Lawrie Brown Danilo S. Almeida Catherine Wearing Hao Zhang Philip M. Haygarth 《Plant and Soil》2018,427(1-2):5-16
Background
Phosphorus (P) fertilizer is usually applied in excess of plant requirement and accumulates in soils due to its strong adsorption, rapid precipitation and immobilisation into unavailable forms including organic moieties. As soils are complex and diverse chemical, biochemical and biological systems, strategies to access recalcitrant soil P are often inefficient, case specific and inconsistently applicable in different soils. Finding a near-universal or at least widely applicable solution to the inefficiency in agricultural P use by plants is an important unsolved problem that has been under investigation for more than half a century.Scope
In this paper we critically review the strategies proposed for the remobilization of recalcitrant soil phosphorus for crops and pastures worldwide. We have additionally performed a meta-analysis of available soil 31P–NMR data to establish the potential agronomic value of different stored P forms in agricultural soils.Conclusions
Soil inorganic P stocks accounted on average for 1006 ± 115 kg ha?1 (57 ± 7%), while the monoester P pool accounted for 587 ± 32 kg ha?1 (33 ± 2%), indicating the huge potential for the future agronomic use of the soil legacy P. New impact driven research is needed in order to create solutions for the sustainable management of soil P stocks.15.
Yanan Ren Fernanda Ferraz Abbass Jafari Kang Qiuyan Yuan 《Journal of biological engineering》2017,11(1):42
Background
Aerobic granular sludge has become an attractive alternative to the conventional activated sludge due to its high settling velocity, compact structure, and higher tolerance to toxic substances and adverse conditions. Aerobic granular sludge process has been studied intensively in the treatment of municipal and industrial wastewater. However, information on leachate treatment using aerobic granular sludge is very limited.Methods
This study investigated the treatment performance of old landfill leachate with different levels of ammonium using two aerobic sequencing batch reactors (SBR): an activated sludge SBR (ASBR) and a granular sludge SBR (GSBR). Aerobic granules were successfully developed using old leachate with low ammonium concentration (136 mg L?1 NH4 +-N).Results
The GSBR obtained a stable chemical oxygen demand (COD) removal of 70% after 15 days of operation; while the ASBR required a start-up of at least 30 days and obtained unstable COD removal varying from 38 to 70%. Ammonium concentration was gradually increased in both reactors. Increasing influent ammonium concentration to 225 mg L?1 N, the GSBR removed 73 ± 8% of COD; while COD removal of the ASBR was 59 ± 9%. The GSBR was also more efficient than the ASBR for nitrogen removal. The granular sludge could adapt to the increasing concentrations of ammonium, achieving 95 ± 7% removal efficiency at a maximum influent concentration of 465 mg L?1 N. Ammonium removal of 96 ± 5% was obtained by the ASBR when it was fed with a maximum of 217 mg L?1 NH4 +-N. However, the ASBR was partially inhibited by free-ammonia and nitrite accumulation rate increased up to 85%. Free-nitrous acid and the low biodegradability of organic carbon were likely the main factors affecting phosphorus removal.Conclusion
The results from this research suggested that aerobic granular sludge have advantage over activated sludge in leachate treatment.16.
Shu Zhang Jian Huang Rong Hu Guo Guo Xiaoli Shang Jianwei Wu 《Biotechnology letters》2017,39(8):1219-1227
Objective
To engineer Pichia pastoris for heterologous production of cellulase from Musca domestica and explore its potential for industrial applications.Results
A new beta-glucosidase gene (bg), encoding 562 amino acids, was cloned from M. domestica by using rapid amplification of cDNA ends. The gene bg was linked to pPICZαA and expressed in P. pastoris with a yield of 500 mg l?1. The enzyme has the maximum activity with 27.6 U mg?1 towards cellulose. The beta-glucosidase has stable activity from 20 to 70 °C and can tolerate one-mole glucose. It has the maximum activities for salicin (25.9 ± 1.8 U mg?1), cellobiose (40.1 ± 2.3 U mg?1) and cellulose (27.6 ± 3.5 U mg?1). The wide-range substrate activities of the beta-glucosidase were further verified by matrix-assisted laser desorption/ionization mass spectra. Structural analysis shows that the beta-glucosidase belongs to glycoside hydrolase family Ι and possesses O-glycosylation sites.Conclusions
Thus, a multifunctional beta-glucosidase was expressed from M. domestica and provides a potential tool for industrial application of cellulose.17.
Objectives
To optimize the expression of type A ferulic acid esterase (FaeA) from Aspergillus niger in Pichia pastoris X-33 using codon optimization.Results
Recombinant FaeA was purified from the fermentation broth, with the maximum specific activity of 48.4 ± 0.1 U mg?1. Adding it during mashing process for beer brewing raised the filtration rate by 14.5% while the turbidity and viscosity declined by 22 and 6.9%, respectively. Addition of FaeA increased the concentrations of free ferulic acid (FA) and arabinoxylan (AX) in the wort, while the polymeric arabinoxylans content declined significantly.Conclusions
Recombinant FaeA was capable to prevent the oxidative gelation of PAX formation by breaking the cross-linking of FA among AX chains and improve the filtration performance of wort.18.
Qingdai Liu Xiaoqian Ma Haijiao Cheng Ning Xu Jun Liu Yanhe Ma 《Biotechnology letters》2017,39(6):913-919
Objectives
To improve the production of α-ketoglutaric acid (α-KG) from l-glutamate by whole-cell biocatalysis.Results
A novel and highly active l-glutamate oxidase, SmlGOX, from Streptomyces mobaraensis was overexpressed and purified. The recombinant SmlGOX was approx. 64 kDa by SDS-PAGE. SmlGOX had a maximal activity of 125 ± 2.7 U mg?1 at pH 6.0, 35 oC. The apparent Km and Vmax values of SmlGOX were 9.3 ± 0.5 mM and 159 ± 3 U mg?1, respectively. Subsequently, a co-expression plasmid containing the SmlGOX and KatE genes was constructed to remove H2O2, and the protein levels of SmlGOX were improved by codon optimization. Finally, by optimizing the whole-cell transformation conditions, the production of α-KG reached 77.4 g l?1 with a conversion rate from l-glutamate of 98.5% after 12 h.Conclusions
An efficient method for the production of α-KG was established in the recombinant Escherichia coli, and it has a potential prospect in industrial application.19.
M. Abawi R. Rozemeijer P. Agostoni R. C. van Jaarsveld C. S. van Dongen M. Voskuil A. O. Kraaijeveld P. A. F. M. Doevendans P. R. Stella 《Netherlands heart journal》2017,25(9):498-509
Objectives
To assess the effect of body mass index (BMI) on outcome among patients with severe aortic stenosis (AS) admitted for transcatheter aortic valve implantation (TAVI).Background
Being overweight or obese is associated with improved outcome following certain medical treatments, suggesting the existence of a BMI paradox. However, the relationship between BMI and mortality after TAVI remains controversial.Methods
Patients were classified according to World Health Organisation criteria such as normal weight, overweight, or obesity according to their BMI (18.5 to 24.9?kg/m2, 25.0 to 29.9?kg/m2, and ≥30.0?kg/m2, respectively).Results
A total of 549 consecutive patients (age: 80.2 ± 7.5 years; logistic European system for cardiac operative risk evaluation [EuroSCORE]: 17.3 ± 9.9%) who underwent TAVI for AS were included. Of these patients, 43% (n = 237) had normal weight, 36% (n = 200) were overweight, and 20% (n = 112) were obese. There were no differences in peri-operative bleeding or vascular complication rates between the groups. All-cause mortality after 30 days, and 1 year, were higher in normal weight patients compared with overweight and obese patients (7% vs. 5 and 4%, p = 0.383, and 19% vs. 9 and 10%, p = 0.006, respectively). After adjustment for several confounding factors, overweight was associated with a decreased 30-day and 1?year all-cause mortality outcome (hazard ratio [HR] 0.69; 95% confidence interval [CI] 0.47–0.99, and HR 0.65; 95% CI 0.45–0.94, respectively).Conclusions
Despite the well-documented adverse effects of increased body weight on health, being overweight is associated with improved survival following TAVI when compared with normal weight.20.