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Oily wastewater and oil spills pose a threat to the environment and human health, and absorbing these harmful organics through porous aerogel materials is an efficient method for oil/water separation.

Objective There are no specific magnetic resonance imaging (MRI) features that distinguish pilocytic astrocytoma (PA) from adamantinomatous craniopharyngioma (ACP). In this study we compared the frequency of a novel enhancement characteristic on MRI (called the cut green pepper sign) in PA and ACP. Methods Consecutive patients with PA (n = 24) and ACP (n = 36) in the suprasellar region were included in the analysis. The cut green pepper sign was evaluated on post-contrast T1WI images independently by 2 neuroradiologists who were unaware of the pathologic diagnosis. The frequency of cut green pepper sign in PA and ACP was compared with Fisher’s exact test. Results The cut green pepper sign was identified in 50% (12/24) of patients with PA, and 5.6% (2/36) with ACP. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the cut green pepper sign for diagnosing PA were 50%, 94.4%, 85.7% and 73.9%, respectively. There was a statistically significant difference in the age of patients with PA with and without the cut green pepper sign (12.3 ± 9.2 years vs. 5.5 ± 4.4 years, p = 0.035). Conclusion The novel cut green pepper sign can help distinguish suprasellar PA from ACP on MRI.

Background: To explore the clinical application value of preoperative colonoscopy in patients with anal fistula. Methods: (1) This study analyzed 1796 patients with benign anorectal diseases who underwent preoperative intestinal endoscopy and met the surgical criteria in the past three years at the First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine. Of these patients, 949 with anal fistula were classified as group A and 847 non-anal fistula patients were classified as group B. We compared and analyzed the general information, endoscopic findings, pathological characteristics of polyp, distribution of bowel-inflammation location, and inflammatory bowel disease examination results between the two groups of patients. (2) 2275 anal fistula patients without surgical contraindications in the past three years at the hospital were selected. Based on whether they underwent preoperative intestinal endoscopy, 949 anal fistula patients who underwent preoperative intestinal endoscopy were classified as group A and 1326 anal fistula patients who did not were classified as group C. This study compared the detection rate of endoscopic lesions and IBD results between the two groups of patients. Results: (1) There was no statistically significant difference in general information between groups A and B, indicating comparability. However, the abnormal detection rate in group A was higher than that in group B（P＜0.01）. In terms of endoscopic findings, the detection rate of bowel inflammation, IBD, and polyps in the anal fistula group was higher than that in the non-anal fistula group（P＜0.05）. Regarding the location of inflammation, group A exhibited a higher detection rate in the terminal ileum, ileocecal region, and ascending colon than group B（P＜0.05）. The incidence of IBD in group A was higher than that in group B, but there was no statistically significant difference between the two groups（P＞0.05）. (2) The study found that there was a statistically significant difference in the intestinal endoscopic detection rate between the two anal fistula groups (groups A and C)（P＜0.01）. The detection rate of IBD in the two anal fistula groups (groups A and C) had statistical significance（P＜0.05）. The detection rate of Crohn's disease in the two anal fistula groups (groups A and C) also had statistical significance（P＜0.05）. Conclusions: Preoperative colonoscopy is of great clinical value in the preoperative evaluation of patients with anal fistula, and it is necessary to perform preoperative colonoscopy to exclude localized perianal lesions caused by inflammatory bowel disease, thereby reducing the rate of missed diagnoses and improving treatment outcomes.

Probiotic Escherichia coli Nissle 1917 (EcN) with different modifications has exhibited multiple superiorities in the prevention and treatment of inflammatory bowel disease.

Background: Human infection with Chlamydia abortus is very rare, mainly described as septicemia and abortion in pregnant women with previous Chlamydia abortus exposure. Though there is a case of atypical pneumonia caused by Chlamydia abortus in 2016, none of the reported infections manifested primarily as severe hypoxemia. Case Presentation: A 69-year-old male farmer admitted to our ICU for pneumonia caused severe hypoxemia, with PaO2 /FiO2 ratio dropped to 53.1 mmHg when under mechanical ventilation. Bronchoalveolar lavage fluid(BALF) for untargeted metagenomic NGS was taken soon after VV- ECMO support. Sequencing results indicate Chlamydia abortus is the pathogen. The patient operated a farm raising more than a hundred pigs and some poultry before the disease, with no ruminant in the farm, and the possibility of contact was denied. Two weeks later, the patient was weaned from ECMO, recovered, and was discharged a month later. Conclusion: Chlamydia abortus infection in humans may as well cause severe pneumonia with hypoxemia and need ECMO support. clinician veterinarians and public health officials should be aware of possible severe pulmonary infection due to Chlamydia abortus.

Background: We recently reported the differential circRNAs expression patterns of the pulmonary macrophages in sepsis induced ARDS mice model by microarray analysis; However, their function and hidden molecular mechanism in regulation of macrophage activation and inflammation remains poorly understood. Methods: Serum were obtained from ARDS patients post sepsis and control subjects. Mice were subjected to Cecal ligation and puncture (CLP) surgery and intravenously injected with si-circN4bp1 plasmid transfected macrophages. Raw264.7 cells and MH-S cells were transfected with circN4bp1 overexpression or silence vectors and then polarized as M1 or M2 macrophages in vitro. Findings: CircN4bp1 was overexpressed in PBMC and monocytes and its expression levels were correlated with a poor prognosis in ARDS patients induced by sepsis. Knockdown of circN4bp1 inhibited the lung injury and improved the long-time survival through blunting the M1 macrophage activation in ARDS mice. Moreover, bioinformatics analysis predicated a circN4bp1/miR-138-5p ceRNA network, which was confirmed by Luciferase reporter assay and RNA binding protein immunoprecipitation (RIP). CircN4bp1 affected macrophage differentiation by binding to miR-138-5p, thus regulating the expression of EZH2 in vivo and ex vivo . Lastly, the m6A level of circN4bp1 was found to be elevated in ARDS mice; inhibition of m6A methyltransferases METTL3 blocked this response in vitro. Interpretation: CircN4bp1 can function as a miR-138-5p sponge for the modulation of macrophage polarization through regulation the expression of EZH2 and may serve as a potential target and/or prognostic marker for ARDS patients following sepsis. Funding: The National Natural Science Foundation of China (81970072 and 81670690), the leading medical talent project of Shanghai Pudong heath bureau (PWRI2019‐05 and PWR12020-07), the Shanghai Scientific Committee of China (20Y11901200, 21ZR1452400, 20ZR1445800 and 13PJ1406900). Declaration of Interest: The authors declare that they have no competing interests. Ethical Approval: The manuscript contains animal experiments that have been approved by the Animal Use Committee of East Hospital/Tongji University, China. The manuscript contains human subjects that have been approved by the Research Ethics Board of East Hospital, Tongji University. All recruited patients or their authorized family members were given a written consent document.

In this study, we have established a convenient and efficient approach named Modification of DNA Regions with Metagenomic DNA Fragments (MDRMDF) for protein engineering. Degenerate primers were designed corresponding to conserved regions of the gene of interest which were used for amplification of fragments with template of the metagenomic DNA. The resulting PCR products were used to replace the corresponding regions of the gene of interest to introduce modified gene for function-based screening. Therefore, this method can make full use of the metagenomic DNA sequences with unknown metagenomic gene information for efficient protein engineering. The β-xylosidase BH3683 was used to construct a MDRMDF library which was screened with a newly designed p-NPX-M9 medium-based strategy. As a result, a mutant protein Xyl-M56 showing high activity, improved pH stability and higher tolerance to organic solvents was obtained which may have potential for industrial application. The MDRMDF method may find wide application in enzyme engineering, metabolic engineering and other fields, especially offering a new methodological option for the directed evolution of proteins.

Dialyzed tilapia skin collagen sponge (DTSCS) and self-assembled tilapia skin collagen sponge (STSCS) were prepared by freeze-drying. The raw components used in the fabrication of DTSCS and STSCS were separated and purified from tilapia fish skin. It is anticipated that these collagen sponges could be developed into medical dressings for hemostasis and wound healing. The aim of the present research was to explore the possibility of DTSCS and STSCS as medical dressings and compare their differences by scanning electron microscopy (SEM), water absorption measurement, differential scanning calorimetry (DSC), measurement of porosity, cytotoxicity, hemolysis, in vivo biocompatibility, and evaluation of hemostatic performance and wound healing. The results indicate that DTSCS and STSCS are suitable materials for use in medical applications with a loose and porous structure, high water absorption, high porosity, and high thermal stability. The materials also displayed good biocompatibility, including excellent blood compatibility, a lack of cytotoxicity, with no apparent rejection following implantation. STSCS exhibited rapid hemostasis and promoted healing, with slightly greater efficacy than DTSCS. The hemostatic properties and promotion of healing in DTSCS was similar to that of commercial bovine collagen sponge. Therefore, DTSCS and STSCS both represented excellent potential candidate materials for use as hemostatic agents and wound dressings.

Finfish cage culture is the most predominant form of mariculture. The rapid expansion of fish cage culture systems has raised concerns about their environmental impact, such as nutrient release. In this study, for the first time, we estimated the release of nitrogen (N) and phosphorus (P) from fish cage culture in Daya Bay, southern China, by constructing N and P budget models based on a mass balance principle. In addition, the contribution and importance of nutrients from fish culture and other nutrient sources, including submarine groundwater discharge, benthic sediments, local rivers, and atmospheric deposition were assessed. The annual amount of N and P released from fish cage culture was 205.6 metric tons (hereafter tons) of N and 39.2 tons of P, including 142.7 tons of dissolved inorganic nitrogen (DIN) and 15.1 tons of dissolved inorganic phosphorus (DIP). Among the analyzed nutrient sources, the contributions of DIN and DIP from fish culture were 7.0% and 2.7%, respectively. For cages consuming conventional trash fish, 142 kg of N and 26 kg of P were released into the environment per ton of fish products, much higher than the values (72 kg N and 17.3 kg P) for cages using formulated feed. In fish culture, the dissolved nutrients were more N rich, but the particulate nutrients were more P rich. The ratio of cage-derived N and P was 21.1, higher than the ratio of coastal seawater (27.1), indicating that cage culture may also impact the local nutrient forms around farming regions. Oyster cultivation and harvest removed 126.3 tons of N and 35.1 tons of P from of the bay. Replacing trash fish with formulated feed and co-culturing of nutrient extractive species (e.g., bivalves, macroalgae) and deposit-feeding species (e.g., sea cucumber) in fish culture zones can be efficient nutrient mitigation strategies.

Summary: The seasonal patterns of the denitrifiers (denitrifying bacteria) in the sediment of Daya Bay, southern China, were examined using quantitative PCR and high-throughput MiSeq sequencing methods in spring, summer and winter. The abundance and diversity of nirS-encoding denitrifiers were much higher than that of nirK-encoding denitrifiers, indicating that the former probably dominated the denitrification processes in sediments of Daya Bay. The average abundance and diversity of nirS-encoding denitrifiers were much higher in spring than that in summer and winter, on the other hand, the abundance of nirK-encoding denitrifiers showed the opposite pattern. The species composition of nirS-encoding denitrifiers community in spring differed significantly from that in summer and winter, whereas, no significant difference existed between summer and winter. The dominant environmental drivers for the diversity of community species were NO2−, NO3− and DO concentrations. The abundances of dominant genera of nirS- encoding denitrifiers, Accumulibacter sp. and Cuprizvidus sp., were significantly higher in summer and winter than that in spring, and were negatively correlated with NO2−, NO3−, and DO concentrations (p

A formaldehyde-degrading bacteria strain, B1, was isolated. Strain B1 was characterized morphologically, physiologically and biochemically, and it was identified as Pseudomonas putida. Then, the formaldehyde biodegradation characteristics were evaluated in a biofilter. A formaldehyde removal rate above 90% was maintained when inlet loading was below 38.9 mg L−1 h−1. In addition, strain B1 quickly became dominant bacteria when the reactor was restarted following a 30-days’ disruption, illustrating that the strain is both adaptable and resilient. The numerical simulation results demonstrate that the maximum degradation rates in the biofilter with strain B1 are better fitted with the Haldane model.

Introduction The disruption of the balance between antioxidants and oxidants plays a vital role in the pathogenesis of acute lung injury (ALI). Evidence has shown that Lycium barbarum polysaccharide (LBP) has antioxidant feature. We examined the efficacy and mechanisms of LBP on hyperoxia-induced acute lung injury (ALI) in the present study. Materials and methods C57BL/6 wild-type (WT) mice and nuclear factor erythroid 2-related factor 2 (Nrf2)-deficient (Nrf2–/–) mice were used in the present study. LBP was fed by gavages once daily for 1 week. Then, the mice were exposed to hyperoxia or room air for 72 h. Additional dosage of LBP was given per 24 h. Results Reactive oxygen species production was increased in WT mice exposed to hyperoxia. Inflammatory cytokines including interleukin (IL)-1β as well as IL-6, and inflammatory cells were increased infiltration in the lung after 3 days hyperoxia exposure. Hyperoxia exposure also induced pulmonary edema and histopathological changes. These hyperoxia-induced changes were improved in LBP treated group. Moreover, elevated activities of heme oxygenase-1 and glutathione peroxidase and enhanced activation of Nrf2 were observed in mice treated with LBP. However, the benefit of LBP on hyperoxic ALI was abolished in Nrf2–/– mice. Moreover, our cell study showed that the LBP-induced activation of Nrf2 was dampened in pulmonary microvascular endothelial cells when the AMPK signal was inhibited by siRNA. Conclusions LBP improves hyperoxic ALI via Nrf2-dependent manner. The LBP-induced activation of Nrf2 is mediated, at least in part, by AMPK pathway.

Here a versatile fusion tag composed of His-tag, intein, and elastin-like polypeptide (ELP) tag was prepared for the first time to be fused with levansucrase SacB to construct a recombinant His-ELP-intein-SacB (HEIS) protein to realize nonchromatographic purification of SacB. The efficient biomimetic mineralization of CaHPO

Glycolate is widely used in industry, especially in the fields of chemical cleaning, cosmetics, and medical materials, and has broad market prospects for the future. Recent advances in metabolic engineering and synthetic biology have significantly improved the titer and yield of glycolate. However, an expensive inducer was used in previous studies, which is not feasible for use in large-scale industrial fermentations. To constitutively biosynthesize glycolate, the expression level of each gene of the glycolate synthetic pathway needs to be systemically optimized. The main challenge of multigene pathway optimization is being able to select or screen the optimum strain from the randomly assembled library by an efficient high-throughput method within a short time. To overcome these challenges, we firstly established a glycolate-responsive biosensor and developed agar plate- and 48-well deep-well plate-scale high-throughput screening methods for the rapid screening of superior glycolate producers from a large library. A total of 22 gradient-strength promoter–5′-untranslated region (UTR) complexes were randomly cloned upstream of the genes of the glycolate synthetic pathway, generating a large random assembled library. After rounds of screening, the optimum strain was obtained from 6 × 10(5) transformants in a week, and it achieved a titer of 40.9 ± 3.7 g/liter glycolate in a 5-liter bioreactor. Furthermore, high expression levels of the enzymes YcdW and GltA were found to promote glycolate production, whereas AceA has no obvious impact on glycolate production. Overall, the glycolate biosensor-based pathway optimization strategy presented in this work provides a paradigm for other multigene pathway optimizations. IMPORTANCE The use of strong promoters, such as pTrc and T7, to control gene expression not only needs the addition of expensive inducers but also results in excessive protein expression that may result in unbalanced metabolic flux and the waste of cellular building blocks and energy. To balance the metabolic flux of glycolate biosynthesis, the expression level of each gene needs to be systemically optimized in a constitutive manner. However, the lack of high-throughput screening methods restricted glycolate synthetic pathway optimization. Our work firstly established a glycolate-response biosensor, and agar plate- and 48-well plate-scale high-throughput screening methods were then developed for the rapid screening of optimum pathways from a large library. Finally, we obtained a glycolate-producing strain with good biosynthetic performance, and the use of the expensive inducer isopropyl-β-d-thiogalactopyranoside (IPTG) was avoided, which broadens our understanding of the mechanism of glycolate synthesis.

Aim of the study The aim of the study was to fabricate collagen-based composite dressings, evaluate the efficiency for wound healing and reveal the mechanism of promoting wound healing. Materials and methods An innovative bi-layered composite wound dressing was developed using two marine biomacromolecules (collagen and chitosan). Full-thickness skin defect model was performed to evaluate the wound healing activity in vivo. The levels of inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin (IL-1, IL-6, IL-8) and growth factors like transforming growth factor beta (TGF-β), vascular epidermal growth factor (VEGF) and basic fibroblast growth factor (bFGF) were quantified by ELISA assays. The total amount of collagen was quantified by hydroxyproline content. The proliferation and viability of fibroblast cells cultured on collagen sponges were determined by CCK-8 assay. Results The results of wound closure and histopathological analysis indicated that non-crosslinked collagen-based bi-layered composite dressing stimulated wound healing, accelerated re-epithelialization and accomplished wound healing within a time span of 28 days. The results of levels of inflammatory cytokines and growth factors showed that collagen-based composite dressings could reduce the inflammatory response and upregulate growth factors levels to accelerate the wound healing. The results of hydroxyproline content and CCK-8 assay indicated that collagen-based composite dressings could also promote collagen synthesis and fibroblasts viability and proliferation. Conclusion The non-crosslinked collagen-based bi-layered composite dressing could be applied for an efficient and ideal wound dressing. Therefore, the findings provided the essential theoretical basis for the potential of collagen-based composite dressing applied in wound healing fields.

In this study, some novel plasmids have been constructed for flexible and zero-background molecular cloning, more efficient expression, and purification of proteins with improved strategies. The plasmids pANY4-pL18-ccdB and pANY4-pR18/pL18-ccdB have different promoters in the complementary DNA strands. Therefore, recombinant plasmids for either isopropyl-β-d-thiogalactoside-induced or temperature-induced protein expression could be simultaneously constructed in a single molecular cloning process for parallel comparison. Intriguingly, the mutated pL18 and pR18/pL18 promoters performed similar to or even better than the T7 promoter when used for promoting the expression of the GFP or pfLamA enzyme. Moreover, the plasmid pANY8 containing the His-elastin-like polypeptide (ELP)-intein multifunctional tag was constructed, and special purification protocol was designed to obtain purified proteins without the requirement of time-consuming dialysis steps to remove imidazole and high concentration of salt ions. Additionally, the urea-based denaturation and refolding processes can be conveniently integrated into the ELP-mediated precipitation protocol for purification of insoluble inclusion bodies, omitting the time-consuming dialysis steps.

The development of smart size-tunable drug delivery nanoplatform enables the solving of the paradox of inconsistent size-dependence of high tumor accumulation and deep penetration during its delivery process, thus achieving superior cancer treatment efficacy. Herein, we report a size-shrinkable nanomicelle complex system with an initial size of 101 nm enabling effective retention around the tumor periphery and could destruct to ultrasmall nanomicelles triggered by a near-infrared (NIR) laser to realize the deep tumor penetration. The nanomicelle system is consisted of an upper critical solution temperature (UCST)-type block copolymer poly(acrylamide-acrylonitrile)-polyethylene glycol-lipoic acid (p(AAm-co-AN)-g-PEG-LA) encapsulating gold nanorods. Upon the irradiation of the NIR laser at the tumor site, gold nanorods could convert the light energy to heat energy, realizing the photothermal ablation of superficial tumor tissue. Concurrently, the large micelles split into a cascade of ultrasmall micelles (∼7 nm), which could easily penetrate into the deep site of the tumor and achieve the in situ "on-demand" release of the loaded drug to exert superior combined photothermal-chemotherapy of cancer. By the precise manipulation of laser, the micelle complex system realized the hierarchical killing from the superficial-to-deep tumor and achieved almost complete tumor growth inhibition on the established xenograft liver tumor mice model.

7-Ethyl-10-hydroxycamptothecin (SN-38) as a potent anti-tumor candidate, suffers the constraints from its poor water solubility, pH-dependent lactone ring stability and the lack of efficient delivery system without losing its activity. Herein, biocompatible superparamagnetic chitosan-based nanocomplexes complexing with water-soluble polymeric prodrug poly(L-glutamic acid)-SN-38 (PGA-SN-38) was engineered for efficient delivery of SN-38. The manufacturing process of colloidal complexes was green, expeditious and facile, with one-shot addition of PGA-SN-38 into chitosan solution without using any organic solvent or surfactant. Upon introducing ultra-small-size superparamagnetic nanoparticles (~10 nm), the developed magnetic nanocomplexes exhibited significantly boosted tumor-targeted accumulation and efficient cellular internalization under a local magnetic field. Notably, the magnetic nanocomplexes achieved distinctly superior targeting and anti-tumor efficacy in the established xenograft colorectal cancer model of mice, with high tumor suppression rate up to 81%. Therefore, this superparamagnetic chitosan-based nanocomplex system could provide a promising platform for the targeted delivery of SN-38 in colorectal cancer therapy.

In this study, curdlan-based and calcium ion (Ca

This study sets out to establish the comparative contribution of PD-L1 expression by pulmonary endothelial cells (ECs) and/or epithelial cells (EpiCs) to the development of indirect acute lung injury (iALI) by taking advantage of the observation that treatment with naked siRNA by intratracheal delivery in mice primarily affects lung EpiCs, but not lung ECs, while intravenous delivery of liposomal-encapsulated siRNA largely targets vascular ECs including the lung, but not pulmonary EpiCs. We showed that using a mouse model of iALI [induced by hemorrhagic shock followed by septic challenge (Hem-CLP)], PD-L1 expression on pulmonary ECs or EpiCs was significantly upregulated in the iALI mice at 24 h post–septic insult. After documenting the selective ability of intratracheal versus intravenous delivery of PD-L1 siRNA to inhibit PD-L1 expression on EpiCs versus ECs, respectively, we observed that the iALI-induced elevation of cytokine/chemokine levels (in the bronchoalveolar lavage fluid, lung lysates, or plasma), lung myeloperoxidase and caspase-3 activities could largely only be inhibited by intravenous, but not intratracheal, delivery of PD-L1 siRNA. Moreover, intravenous, but not intratracheal, delivery led to a preservation of normal tissue architecture, lessened pulmonary edema, and reduced neutrophils influx induced by iALI. In addition, in vitro mouse endothelial cell line studies showed that PD-L1 gene knockdown by siRNA or knockout by CRISPR/Cas9-mediated gene manipulation, reduced monolayer permeability, and maintained tight junction protein levels upon recombinant IFN-γ stimulation. Together, these data imply a critical role for pulmonary vascular ECs in mediating PD-1:PD-L1–driven pathological changes resulting from systemic stimuli such as Hem-CLP.

T follicular regulatory (Tfr) cell is a CXCR5+Foxp3+ subset of T regulatory (Treg) cell with critical roles in regulating germinal center responses and modulating the immune environment in the lymph nodes. Studies have shown that the proportion of Tfr cells may increase during acute inflammation. In this study, we investigated the role of Tfr cells in acute respiratory distress syndrome (ARDS). We found that Tfr cells were significantly enriched in peripheral blood and in mini-bronchoalveolar lavage (BAL) during the onset of ARDS. Notably, Tfr cells represented the majority of Treg cells in the mini-BAL samples. Tfr cells also showed CTLA-4, IL-10, and TGF-β expression, but compared to the non-Tfr Treg cells, the CTLA-4 and IL-10 expression by Tfr cells were slightly reduced. Both Tfr cells and non-Tfr Treg cells suppressed the proliferation of autologous CD4+CD25− T cells; however, the Tfr cells displayed slightly reduced suppression capacity. Subsequently, B cells were co-incubated with autologous Tfr cells or non-Tfr Treg cells. Interestingly, we found that the frequency of IL-10+ Breg cells was significantly higher following incubation with Tfr cells than with non-Tfr Treg cells, which suggested that Tfr cells were more potent at inducing IL-10+ Breg cells. Together, these results demonstrated that Tfr cells were a similar but distinctive subset of Treg cells. Given that Tfr cells were strongly enriched in ARDS patients, especially in the lung infiltrates, they may exert critical ameliorating effects in ARDS.

International audience; We have constructed novel plasmids pANY2, pANY3, and pANY6 for flexible cloning with low false positives, efficient expression, and convenient purification of proteins. The pANY2 plasmid can be used for efficient isopropyl-β-d-thiogalactoside (IPTG) induced protein expression, while the pANY3 plasmid can be used for temperature-induced expression. The pANY6 plasmid contains a self-cleaving elastin-like protein (ELP) tag for purification of recombinant protein by simple ELP-mediated precipitation steps and removal of the ELP tag by self-cleavage. A urea-based denaturation and refolding processes for renaturation of insoluble inclusion bodies can be conveniently integrated into the ELP-mediated precipitation protocol, removing time-consuming dialysis steps. These novel vectors, together with the described strategies of gene cloning, protein expression, and purification, may have wide applications in biosciences, agricultural, food technologies, and so forth.

International audience; Currently, the most widely used strategies for molecular cloning are sticky-end ligation-based cloning, TA cloning, blunt-end ligation-based cloning and ligase-independent cloning. In this study we have developed a novel mini-vector pANY1 which can simultaneously meet the requirements of all these cloning strategies. In addition, the selection of appropriate restriction digestion sites is difficult in some cases because of the presence of internal sites. In this study, an annealing of PCR products (APP)-based sticky-end cloning strategy was introduced to avoid this issue. Additionally, false positives occur during molecular cloning, which increases the workload of isolating positive clones. The plasmid pANY1 contains a ccdB cassette between multiple cloning sites, which efficiently avoids these false positives. Therefore, this mini-vector should serve as a useful tool with wide applications in biosciences, agriculture, food technologies, etc.

In this study, curdlan-based and calcium ion (Ca2+)-chelated magnetic microspheres (CCMM) were prepared for protein purification and oriented immobilization. Additional purification steps before immobilization were not required. CCMM samples were produced by reverse embedding of Fe3O4 nanoparticles with curdlan and chelated with Ca2+ in the presence of iminodiacetic acid. The β-xylanase XynII from Trichoderma reesei QM6a was used to investigate the efficiency of CCMM preparation. The resulting CCMM-XynII was found to be very stable, showing 82 % and 60 % of initial activities after storage for 35 days and after being assayed ten times, respectively. In addition, the CCMM-XynII showed higher stabilities in the presence of organic solvents and multiple chemicals than the free XynII, suggesting that the CCMM-XynII could be efficient for applications requiring the presence of organic solvents. In addition, CCMM may be more suitable than commercially available Ni-NTA for purification of proteins intolerant of Ni2+.

In this paper, the Mg-based Mg66Zn30Gd4 amorphous ribbons were successfully prepared using a single roller melt-spinning technique. Subsequently, the non-isothermal crystallization behaviors of alloy ribbons were investigated by differential scanning calorimetry (DSC) and resistivity method, and its crystallization process and microstructure were confirmed by X-ray, transmission electron microscope (TEM) and selected area electron diffraction (SAED). The results show that: the negative temperature coefficient of resistivity (TCR) exists in the crystallization process, and the crystallization process of melt-spun Mg66Zn30Gd4 ribbons consists of three steps. The first crystallization reaction at about 385 K is connected with the formation of the ICQ-phase, followed by the formation of the Mg7Zn3 binary phase and the Mg3(Gd, Zn) ternary phase (468–538 K), and then the formation of the α-Mg phase at about 538 K. Furthermore, the formation of the ICQ-phase reflects the heredity of icosahedral local order.

Utterance-level permutation invariant training (uPIT) has achieved promising progress on single-channel multi-talker speech separation task. Long short-term memory (LSTM) and bidirectional LSTM (BLSTM) are widely used as the separation networks of uPIT, i.e. uPIT-LSTM and uPIT-BLSTM. uPIT-LSTM has lower latency but worse performance, while uPIT-BLSTM has better performance but higher latency. In this paper, we propose using latency-controlled BLSTM (LC-BLSTM) during inference to fulfill low-latency and good-performance speech separation. To find a better training strategy for BLSTM-based separation network, chunk-level PIT (cPIT) and uPIT are compared. The experimental results show that uPIT outperforms cPIT when LC-BLSTM is used during inference. It is also found that the inter-chunk speaker tracing (ST) can further improve the separation performance of uPIT-LC-BLSTM. Evaluated on the WSJ0 two-talker mixed-speech separation task, the absolute gap of signal-to-distortion ratio (SDR) between uPIT-BLSTM and uPIT-LC-BLSTM is reduced to within 0.7 dB., Proceedings of APSIPA Annual Summit and Conference 2019, 18-21 November 2019, Lanzhou, China

The biosynthesis of various useful chemicals from simple substrates using industrial microorganisms is becoming increasingly crucial to address the challenge of dwindling non-renewable resources. As the most common intermediate substrates in organisms, Coenzyme A (CoA) thioesters play a central role in the carbon chain elongation process of their products. As a result, numerous of chemicals can be synthesized by the iterative addition of various CoA thioester extender units at a given CoA thioester primer backbone. However, these elongation reactions and the product yields are still restricted due to the low enzymatic performance and supply of CoA thioesters. This review highlights the current protein and metabolic engineering strategies used to enhance the diversity and product yield by coupling different primers, extender units, enzymes, and termination pathways, in an attempt to provide a road map for producing a more diverse range of industrial chemicals.