ABSTRACT
The construction of atropisomers with 1,2-diaxes, while maintaining high enantiocontrol, presents a significant challenge due to the dynamic nature of steric hindrance at ortho-aryl substituents. Although various catalytic asymmetric methods have been developed for accessing axially chiral arylpyrroles, the synthesis of axially chiral arylpyrroles with 1,2-diaxes in a catalytic asymmetric manner has remained rare. Herein, the authors report the synthesis of diverse axially chiral arylpyrroles with 1,2-diaxes, and C-C and C-N axes through copper-catalysed asymmetirc [4 + 1] annulation of yne-allylic esters with arylamines via a remote stereocontrol strategy. This approach provides facile access to a broad range of heterobiaryl atropisomers (67 examples) in excellent enantioselectivities, each bearing one or two C-C/C-N axes, demonstrating its versatility and efficiency. The utility of this methodology is further highlighted by the transformation of the product into chiral phosphine ligand, and chiral thioureas for the use in asymmetric catalysis.
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PURPOSE: Patients with spinal metastases undergoing surgical treatment face challenges related to preoperative anemia, intraoperative blood loss, and frailty, emphasizing the significance of perioperative blood management. This retrospective analysis aimed to assess the correlation between hemoglobin-related parameters and outcomes, identifying key markers to aid in blood management. METHODS: A retrospective review was performed to identify patients who underwent surgical treatment for spinal metastases. Hb-related parameters, including baseline Hb, postoperative nadir Hb, predischarge Hb, postoperative nadir Hb drift, and predischarge Hb drift (both in absolute values and percentages) were subjected to univariate and multivariate analyses. These analyses were conducted in conjunction with other established variables to identify independent markers predicting patient outcomes. The outcomes of interest were postoperative short-term (6-week) mortality, long-term (1-year) mortality, and postoperative 30-day morbidity. RESULTS: A total of 289 patients were included. Our study demonstrated that predischarge Hb (OR 0.62, 95% CI 0.44-0.88, P = 0.007) was an independent prognostic factor of short-term mortality, while baseline Hb (OR 0.76, 95% CI 0.66-0.88, P < 0.001) was identified as an independent prognostic factor of long-term mortality. Additionally, nadir Hb drift (OR 0.82, 95% CI 0.70-0.97, P = 0.023) was found to be an independent prognostic factor for postoperative 30-day morbidity. CONCLUSIONS: This study demonstrated that predischarge Hb, baseline Hb, and nadir Hb drift are prognostic factors for outcomes. These findings provide a foundation for precise blood management strategies. It is crucial to consider Hb-related parameters appropriately, and prospective intervention studies addressing these markers should be conducted in the future.
Subject(s)
Hemoglobins , Spinal Neoplasms , Humans , Male , Female , Retrospective Studies , Middle Aged , Hemoglobins/analysis , Aged , Spinal Neoplasms/secondary , Spinal Neoplasms/surgery , Spinal Neoplasms/blood , Spinal Neoplasms/mortality , Blood Loss, Surgical/statistics & numerical data , Blood Loss, Surgical/prevention & control , Treatment Outcome , Anemia/blood , Anemia/diagnosis , Adult , Prognosis , Blood Transfusion/statistics & numerical data , Biomarkers/blood , Postoperative Complications/blood , Postoperative Complications/etiology , Postoperative Complications/diagnosis , Postoperative Complications/epidemiologyABSTRACT
In this work, we report on an electrochemical method for the signal-on detection of caspase-3 and the evaluation of apoptosis based on the biotinylation reaction and the signal amplification of methylene blue (MB)-loaded metal-organic frameworks (MOFs). Zr-based UiO-66-NH2 MOFs were used as the nanocarriers to load electroactive MB molecules. Recombinant hexahistidine (His6)-tagged streptavidin (rSA) was attached to the MOFs through the coordination interaction between the His6 tag in rSA and the metal ions on the surface of the MOFs. The acetylated peptide substrate Ac-GDEVDGGGPPPPC was immobilized on the gold electrode. In the presence of caspase-3, the peptide was specifically cleaved, leading to the release of the Ac-GDEVD sequence. A N-terminal amine group was generated and then biotinylated in the presence of biotin-NHS. Based on the strong interaction between rSA and biotin, rSA@MOF@MB was captured by the biotinylated peptide-modified electrode, producing a significantly amplified electrochemical signal. Caspase-3 was sensitively determined with a linear range from 0.1 to 25 pg/mL and a limit of detection down to 0.04 pg/mL. Further, the active caspase-3 in apoptosis inducer-treated HeLa cells was further quantified by this method. The proposed signal-on biosensor is compatible with the complex biological samples and shows great potential for apoptosis-related diagnosis and the screening of caspase-targeting drugs.
Subject(s)
Biosensing Techniques , Caspase 3 , Metal-Organic Frameworks , Methylene Blue , Metal-Organic Frameworks/chemistry , Methylene Blue/chemistry , Humans , Caspase 3/metabolism , HeLa Cells , Biosensing Techniques/methods , Electrochemical Techniques/methods , Apoptosis , Streptavidin/chemistry , Biotinylation , Electrodes , Limit of Detection , Zirconium/chemistry , Phthalic AcidsABSTRACT
All-RNA-mediated targeted gene integration methods, rendering reduced immunogenicity, effective deliverability with non-viral vehicles, and a low risk of random mutagenesis, are urgently needed for next-generation gene addition technologies. Naturally occurring R2 retrotransposons hold promise in this context due to their site-specific integration profile. Here, we systematically analyzed the biodiversity of R2 elements and screened several R2 orthologs capable of full-length gene insertion in mammalian cells. Robust R2 system gene integration efficiency was attained using combined donor RNA and protein engineering. Importantly, the all-RNA-delivered engineered R2 system showed effective integration activity, with efficiency over 60% in mouse embryos. Unbiased high-throughput sequencing demonstrated that the engineered R2 system exhibited high on-target integration specificity (99%). In conclusion, our study provides engineered R2 tools for applications based on hit-and-run targeted DNA integration and insights for further optimization of retrotransposon systems.
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Introduction: The management of soft tissue sarcomas presents considerable therapeutic challenges. This study was designed to assess the efficacy of neoadjuvant sequential chemotherapy and hypofractionated radiotherapy in conjunction with extensive surgical resection for the treatment of high-risk soft tissue sarcomas. Materials and methods: We performed a retrospective review of 31 high-risk soft tissue sarcoma patients treated at our institution from June 2021 to June 2023. The cohort consisted of 21 males and 10 females with a mean age of 55.7 years and included both initial and recurrent disease presentations. Our treatment regimen comprised two to three cycles of neoadjuvant chemotherapy coupled with hypofractionated radiotherapy, delivered at 5 Gy per fraction to a total dose of 25-35 Gy across 5-7 days, prior to surgical resection aimed at achieving wide margins. Data collection was systematic, covering surgical outcomes, chemoradiotherapy-related complications, and prognostic factors. Results: All patients completed the prescribed course of neoadjuvant chemoradiotherapy. 29% patients experienced grade 3+ chemotherapy toxicity, necessitating a reduction or interruption in their chemotherapy regimen. Limb preservation was accomplished in 30 patients finally. Response evaluation using RECIST 1.1 criteria post-neoadjuvant therapy revealed 9.7% with PD, 58.1% with SD, 29% with a PR, and 3.2% with a CR, culminating in an ORR of 32.2%. Postoperative complications included superficial wound infections in four patients and deep incisional infections in another four. 6 patients had developed metastasis, and 3 patients were still alive. Two experienced local recurrence. One-year DFS was 79.3%, with a one-year OS rate of 89.6%. Conclusion: Neoadjuvant sequential chemotherapy and hypofractionated radiotherapy followed by extensive surgical resection represents an effective treatment paradigm for high-risk soft tissue sarcomas. This multimodal approach not only facilitates tumor reduction but also significantly reduces the risks of local recurrence and distant metastasis.
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Oocyte in vitro maturation is a technique in assisted reproductive technology. Thousands of genes show abnormally high expression in in vitro maturated metaphase II (MII) oocytes compared to those matured in vivo in bovines, mice, and humans. The mechanisms underlying this phenomenon are poorly understood. Here, we use poly(A) inclusive RNA isoform sequencing (PAIso-seq) for profiling the transcriptome-wide poly(A) tails in both in vivo and in vitro matured mouse and human oocytes. Our results demonstrate that the observed increase in maternal mRNA abundance is caused by impaired deadenylation in in vitro MII oocytes. Moreover, the cytoplasmic polyadenylation of dormant Btg4 and Cnot7 mRNAs, which encode key components of deadenylation machinery, is impaired in in vitro MII oocytes, contributing to reduced translation of these deadenylase machinery components and subsequently impaired global maternal mRNA deadenylation. Our findings highlight impaired maternal mRNA deadenylation as a distinct molecular defect in in vitro MII oocytes.
Subject(s)
Oocytes , Polyadenylation , Oocytes/metabolism , Animals , Humans , Female , Mice , Poly A/metabolism , In Vitro Oocyte Maturation Techniques , RNA, Messenger/metabolism , RNA, Messenger/genetics , Transcriptome , RNA, Messenger, Stored/metabolism , RNA, Messenger, Stored/genetics , Metaphase , Exoribonucleases , Repressor Proteins , Cell Cycle ProteinsABSTRACT
Ferroptosis, driven by an imbalance in redox homeostasis, has recently been identified to regulate macrophage function and inflammatory responses. SENP3 is a redox-sensitive de-SUMOylation protease that plays an important role in macrophage function. However, doubt remains on whether SENP3 and SUMOylation regulate macrophage ferroptosis. For the first time, the results of our study suggest that SENP3 sensitizes macrophages to RSL3-induced ferroptosis. We showed that SENP3 promotes the ferroptosis of M2 macrophages to decrease M2 macrophage proportion in vivo. Mechanistically, we identified the ferroptosis repressor FSP1 as a substrate for SUMOylation and confirmed that SUMOylation takes place mainly at its K162 site. We found that SENP3 sensitizes macrophages to ferroptosis by interacting with and de-SUMOylating FSP1 at the K162 site. In summary, our study describes a novel type of posttranslational modification for FSP1 and advances our knowledge of the biological functions of SENP3 and SUMOylation in macrophage ferroptosis.
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Enzyme-linked electrochemical immunosensors have attracted considerable attention for the sensitive and selective detection of various targets in clinical diagnosis, food quality control, and environmental analysis. In order to improve the performances of conventional immunoassays, significant efforts have been made to couple enzyme-linked or nanozyme-based catalysis and redox cycling for signal amplification. The current review summarizes the recent advances in the development of enzyme- or nanozyme-based electrochemical immunosensors with redox cycling for signal amplification. The special features of redox cycling reactions and their synergistic functions in signal amplification are discussed. Additionally, the current challenges and future directions of enzyme- or nanozyme-based electrochemical immunosensors with redox cycling are addressed.
Subject(s)
Biosensing Techniques , Electrochemical Techniques , Oxidation-Reduction , Biosensing Techniques/methods , Electrochemical Techniques/methods , Immunoassay/methods , Catalysis , Humans , Enzymes/metabolism , Enzymes/chemistryABSTRACT
Compressed leachate is a contaminated liquid containing various organic and inorganic pollutants produced in municipal refuse transfer stations, which pollute soil and groundwater, posing serious risks to the environment and human health. The Environmental Technology Co., Ltd. (Shenzhen, Guangdong Province, South China) treated compressed leachate obtained from a refuse transfer station. The chemical oxygen demand (COD) (641.2 mg/L) of treated compressed leachate did not meet the wastewater quality standards in China for discharge into municipal sewers (COD ≤ 500 mg/L) and the company's design discharge requirements (COD ≤ 400 mg/L). Therefore, their further in-depth treatment is necessary. To this end, waste tobacco leaves were used as the biotemplate herein, and Fe/La-co-doped TiO2 (xFe,yLa)-TTiO2(g) was synthesized using a solvothermal-assisted biotemplating method. The photocatalytic depth treatment of compressed leachate was performed under simulated solar light using the prepared catalysts. After (3Fe,3La)-TTiO2(g) treatment, the COD of the leachate decreased from 641.2 to 280.1 mg/L, and the COD removal rate was 1.2, 1.1, and 1.6 times higher than that of pure Fe-doped, La-doped and non-biological template TiO2, respectively. Characterization confirmed that the biological template endowed the catalyst with a unique morphology and high specific surface area. Its rich activity sites are conducive to enhancing the adsorption capacity of pollutants and providing an ideal place for photocatalytic reactions. Co-doping with iron and lanthanum ions altered the band structure of TiO2 and promoted the interconversion of Fe3+/Fe2+ and La3+/La2+ during photocatalysis. First-principles density functional theory simulations demonstrated that co-doping Fe and La in TiO2 created impurity levels that facilitated the transfer of photogenerated electrons. This study provides a new purification pathway for the depth treatment of compressed leachate.
Subject(s)
Titanium , Water Pollutants, Chemical , Titanium/chemistry , Water Pollutants, Chemical/chemistry , Iron/chemistry , China , Catalysis , Wastewater/chemistry , Waste Disposal, Fluid/methodsABSTRACT
Organic near-infrared (NIR) room temperature phosphorescence (RTP) materials become a hot topic in bioimaging and biosensing for the large penetration depth and high signal-to-background ratio (SBR). However, it is challenging to achieve persistent NIR phosphorescence for severe nonradiative transitions by energy-gap law. Herein, a universal system with persistent NIR RTP is built by visible (host) and NIR phosphorescence (guest) materials, which can efficiently suppress the nonradiative transitions by rigid environment of crystalline host materials with good matching, and further promote phosphorescence emission by the additional phosphorescence resonance energy transfer (≈100%) between them. The persistent NIR phosphorescence with ten-folds enhancement of RTP lifetimes, compared to those of guest luminogens, can be achieved by modulation of aggregated structures of host-guest systems. This work provides a convenient way to largely prolong the phosphorescence lifetimes of various NIR luminogens, promoting their application in afterglow imaging with deeper penetration and higher SBRs.
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Pol II pause release is a rate-limiting step in gene transcription, influencing various cell fate alterations. Numerous proteins orchestrate Pol II pause release, thereby playing pivotal roles in the intricate process of cellular fate modulation. Super elongation complex (SEC), a large assembly comprising diverse protein components, has garnered attention due to its emerging significance in orchestrating physiological and pathological cellular identity changes by regulating the transcription of crucial genes. Consequently, SEC emerges as a noteworthy functional complex capable of modulating cell fate alterations. Therefore, a comprehensive review is warranted to systematically summarize the core roles of SEC in different types of cell fate alterations. This review focuses on elucidating the current understanding of the structural and functional basis of SEC. Additionally, we discuss the intricate regulatory mechanisms governing SEC in various models of cell fate alteration, encompassing both physiological and pathological contexts. Furthermore, leveraging the existing knowledge of SEC, we propose some insightful directions for future research, aiming to enhance our mechanistic and functional comprehension of SEC within the diverse landscape of cell fate alterations.
Subject(s)
Cell Differentiation , Humans , Animals , Cell Differentiation/physiology , Transcription, GeneticABSTRACT
Antimony (Sb) decontamination in water is necessary owing to the worsening pollution which seriously threatens human life safety. Designing bismuth-based photocatalysts with hydroxyls have attracted growing interest because of the broad bandgap and enhanced separation efficiency of photogenerated electron/hole pairs. Until now, the available photocatalysis information regarding bismuth-based photocatalysts with hydroxyls has remained scarce and the contemporary report has been largely limited to Bi3O(OH)(PO4)2 (BOHP). Herein, Bi3O(OH)(AsO4)2 (BOHAs), a novel ultraviolet photocatalyst, was fabricated via the co-precipitation method for the first time, and developed to simultaneous photocatalytic oxidation and adsorption of Sb(III). The rate constant of Sb(III) removal by the BOHAs was 32.4, 3.0, and 4.3 times higher than those of BiAsO4, BOHP, and TiO2, respectively, indicating that the introduction of hydroxyls could increase the removal of Sb(III). Additionally, the crucial operational parameters affecting the adsorption performance (catalyst dosage, concentration, pH, and common anions) were investigated. The BOHAs maintained 85% antimony decontamination of the initial yield after five successive cycles of photocatalysis. The Sb(III) removal involved photocatalytic oxidation of adsorbed Sb(III) and subsequent adsorption of the yielded Sb(V). With the acquired knowledge, we successfully applied the photocatalyst for antimony removal from industrial wastewater. In addition, BOHAs could also be powerful photocatalysts in the photodegradation of organic pollutants studies of which are ongoing. It reveals an effective strategy for synthesizing bismuth-based photocatalysts with hydroxyls and enhancing pollutants' decontamination.
Subject(s)
Antimony , Bismuth , Oxidation-Reduction , Wastewater , Water Pollutants, Chemical , Antimony/chemistry , Adsorption , Bismuth/chemistry , Wastewater/chemistry , Catalysis , Water Pollutants, Chemical/chemistry , Photochemical Processes , Waste Disposal, Fluid/methodsABSTRACT
Enzymatic degradation of lignocellulosic biomass provides an eco-friendly approach to produce value-added macromolecules, e.g., bioactive polysaccharides. A novel acidophilic GH5 ß-1,4-endoglucanase (termed TaCel5) from Trichoderma asperellum ND-1 was efficiently expressed in Komagataella phaffii (â¼1.5-fold increase, 38.42 U/mL). TaCel5 displayed both endoglucanase (486.3 U/mg) and alginate lyase (359.5 U/mg) enzyme activities. It had optimal pH 3.0 and strong pH stability (exceed 86 % activity retained over pH range 3.0-5.0). 80 % activity (both endoglucanase and alginate lyase) was retained in the presence of 15 % ethanol or 3.42 M NaCl. Analysis of action mode revealed that hydrolytic activity of TaCel5 required at least three glucose (cellotriose) residues, yielding mainly cellobiose. Glu241 and Glu352 are essential catalytic residues, while Asp106, Asp277 and Asp317 play auxiliary roles in cellulose degradation. TaCel5 displayed high hydrolysis efficiency for glucan and alginate substrates. ESI-MS analysis indicated that the enzymatic hydrolysates of alginate mainly contained disaccharides and heptasaccharides. This is the first detailed report of a bifunctional GH5 endoglucanase/alginate lyase enzyme from T. asperellum. Thus TaCel5 has strong potential in food and feed industries as a catalyst for bioconversion of cellulose- and alginate-containing waste materials into value-added products oligosaccharides, which was of great benefit both for the economy and environment.
Subject(s)
Alginates , Cellulase , Cellulose , Oligosaccharides , Alginates/metabolism , Alginates/chemistry , Cellulase/metabolism , Cellulase/chemistry , Oligosaccharides/metabolism , Oligosaccharides/chemistry , Hydrolysis , Cellulose/metabolism , Hydrogen-Ion Concentration , Hypocreales/enzymology , Substrate Specificity , Polysaccharide-Lyases/metabolism , Polysaccharide-Lyases/chemistry , Polysaccharide-Lyases/geneticsABSTRACT
The heterogeneity of CARM1 controls first cell fate bias during early mouse development. However, how this heterogeneity is established is unknown. Here, we show that Carm1 mRNA is of a variety of specific exon-skipping splicing (ESS) isoforms in mouse two-cell to four-cell embryos that contribute to CARM1 heterogeneity. Disruption of paraspeckles promotes the ESS of Carm1 precursor mRNAs (pre-mRNAs). LincGET, but not Neat1, is required for paraspeckle assembly and inhibits the ESS of Carm1 pre-mRNAs in mouse two-cell to four-cell embryos. We further find that LincGET recruits paraspeckles to the Carm1 gene locus through HNRNPU. Interestingly, PCBP1 binds the Carm1 pre-mRNAs and promotes its ESS in the absence of LincGET. Finally, we find that the ESS seen in mouse two-cell to four-cell embryos decreases CARM1 protein levels and leads to trophectoderm fate bias. Our findings demonstrate that alternative splicing of CARM1 has an important role in first cell fate determination.
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π-π coupling as a common interaction plays a key role in emissions, transport and mechanical properties of organic materials. However, the precise control of π-π coupling is still challenging owing to the possible interference from other intermolecular interactions in the aggregated state, usually resulting in uncontrollable emission properties. Herein, with the rational construction of intramolecular dimer models and crystal engineering, π-π coupling can be subtly modulated by conformation variation with balanced π-π and π-solvent interactions and visualized by green-to-blue emission switching. Moreover, it can rapidly respond to temperature, pressure and mechanical force, affording a facile way to modulate π-π coupling in situ. This work contributes to a deeper understanding of the internal mechanism of molecular motions in aggregated states.
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Background: It is still uncertain whether Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) and programmed cell death protein 1 (PD-1) inhibitor have synergistic effects on metastatic soft tissue sarcomas (STSs). The purpose of this study was to evaluate the safety and activity of nab-paclitaxel plus camrelizumab (a PD-1 inhibitor) in patients with advanced STS who had previously failed chemotherapy. Methods: In this single-center, open-label, single-arm phase II clinical trial, patients with advanced (unresectable or metastatic) STS who had previously failed chemotherapy received up to six cycles of nab-paclitaxel plus camrelizumab, whereas camrelizumab treatment was continued for up to 1 year. The median progression-free survival (PFS), objective response rate (ORR) and safety were collected and evaluated. Results: This trial included 40 patients (28 men and 12 women). The overall ORR was 22.5%, and the median PFS was 1.65 months (95% confidence interval [CI], 1.3-2.0 months). Patients with epithelioid sarcoma demonstrated a longer PFS compared with those with other histological subtypes (2.3 months vs. 1.5 months, respectively); however, this difference was not significant. Patients who had received only one line of previous chemotherapy had a significantly longer PFS compared with those who had undergone two or more lines of previous chemotherapy (2.8 months vs. 1.3 months, respectively, p = 0.046). In terms of safety, the toxicity of this combination therapy is mild and no serious adverse events have occurred. Conclusion: Nab-paclitaxel plus camrelizumab exhibited modest activity and mild toxicity in treating epithelioid sarcoma, angiosarcoma, and fibrosarcoma. The overall effectiveness of this treatment regimen for advanced STS is relatively low. Further research on combining nab-paclitaxel with effective drugs, including chemotherapy and targeted agents, for these specific STS subtypes is needed.
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The elimination of antimony pollution has attracted increasing concerns because of its high toxicity to human health and the natural environment. In this work, biomimetic δ-MnO2 was synthesized by using waste tobacco stem-silks as biotemplate (Bio-δ-MnO2) and used in the capture of Sb(III)from aqueous solution. The tobacco stem-silks not only provided unique wrinkled morphologies but also contained carbon element self-doped into the resulting samples. The maximum Sb(III) adsorption capacity reached 763.4 mgâg -1, which is 2.06 times higher than δ-MnO2 without template (370.0 mgâg -1), 4.53 times than tobacco stem-silks carbon (168.5 mgâg -1), and 10.39 times than commercial MnO2 (73.5 mgâg -1), respectively. The isotherm and kinetic studies indicated that the adsorption behavior was consistent with the Langmuir isotherm model and the pseudo-second-order kinetic equation. As far as we are aware, the adsorption capacity of Bio-δ-MnO2 is much higher than that of most Sb(III) adsorbents. FT-IR, XPS, SEM, XRD, and Zeta potential analyses showed that the main mechanism for the adsorption of Sb(III) by Bio-δ-MnO2 includes electrostatic attraction, surface complexation, and redox. Overall, this study provides a new sustainable way to convert agricultural wastes to more valuable products such as biomimetic adsorbent for Sb(III) removal in addition to conventional activated carbon and biochar.
Subject(s)
Oxides , Water Pollutants, Chemical , Humans , Kinetics , Manganese Compounds , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis , AdsorptionABSTRACT
Understanding and management of triplet excitons transition in the same molecule remain a great challenge. Hence, for the first time, by host engineering, manageable transitions of triplet excitons in a naphthalimide derivative NDOH were achieved, and monitored through the intensity ratio (ITADF/IRTP) between thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP). Energy differences between lowest triplet excited states of host and guest were changed from 0.03 to 0.17 eV, and ITADF/IRTP of NDOH decreased by 200 times, thus red shifting the afterglow color. It was proposed that shorter conjugation length led to larger band gaps of host materials, thus contributing to efficient Dexter and inefficient Förster energy transfer. Interestingly, no transition to singlet state and only strongest RTP with quantum yield of 13.9% could be observed, when PBNC with loosest stacking and largest band gap acted as host. This work provides novel insight for the management and prediction of triplet exciton transitions and the development of smart afterglow materials.
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A novel acidophilic GH5 ß-1,4-endoglucanase (TaCel12) from Trichoderma asperellum ND-1 was efficiently expressed in Pichia pastoris (a 1.5-fold increase). Deglycosylated TaCel12 migrated as a single band (26.5 kDa) in SDS-PAGE. TaCel12 was acidophilic with a pH optimum of 4.0 and displayed great pH stability (>80 % activity over pH 3.0-5.0). TaCel12 exhibited considerable activity towards sodium carboxymethyl cellulose and sodium alginate with Vmax values of 197.97 µmol/min/mg and 119.06 µmol/min/mg, respectively. Moreover, TaCel12 maintained >80 % activity in the presence of 20 % ethanol and 4.28 M NaCl. Additionally, Mn2+, Pb2+ and Cu2+ negatively affected TaCel12 activity, while the presence of 5 mM Co2+ significantly increased the enzyme activity. Analysis of action mode revealed that TaCel12 required at least four glucose (cellotetraose) residues for hydrolysis to yield cellobiose and cellotriose. Site-directed mutagenesis results suggested that Glu133 and Glu217 of TaCel12 are crucial catalytic residues, with Asp116 displaying an auxiliary function. Production of soluble sugars from lignocellulose is a crucial step in bioethanol development, and it is noteworthy that TaCel12 could synergistically yield fermentable sugars from corn stover and bagasse, respectively. Thus TaCel12 with excellent properties will be considered a potential biocatalyst for applications in various industries, especially for lignocellulosic biomass conversion.
Subject(s)
Cellulase , Hypocreales , Lignin , Trichoderma , Hydrolysis , Cellulase/genetics , Ethanol , Biomass , Cellobiose , Trichoderma/geneticsABSTRACT
Hypertrophic scar (HS), which results from prolonged inflammation and excessive fibrosis in re-epithelialized wounds, is one of the most common clinical challenges. Consequently, sophisticated transdermal transfersome nanogels (TA/Fu-TS) are prepared to control HS formation by synergistically inhibiting inflammation and suppressing fibrosis. TA/Fu-TSs have unique structures comprising hydrophobic triamcinolone acetonide (TA) in lipid multilayers and hydrophilic 5-fluorouracil in aqueous cores, and perform satisfactorily with regard to transdermal co-delivery to macrophages and HS fibroblasts in emerging HS tissues. According to the in vitro/vivo results, TA/Fu-TSs not only promote macrophage phenotype-switching to inhibit inflammation by interleukin-related pathways, but also suppress fibrosis to remodel extracellular matrix by collagen-related pathways. Therefore, TA/Fu-TSs overcome prolonged inflammation and excessive fibrosis in emerging HS tissues, and provide an effective therapeutic strategy for controlling HS formation via their synergy of macrophage phenotype-switching and anti-fibrosis effect.