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1.
Bioresour Technol ; 399: 130579, 2024 May.
Article En | MEDLINE | ID: mdl-38479628

An effective deep eutectic solvent (DES) and Iron(III) chloride (FeCl3) combination pretreatment system was developed to improve the removal efficiency of lignin and hemicellulose from corn stover (CS) and enhance its saccharification. N-(2-hydroxyethyl)ethylenediamine (NE) was selected as the hydrogen-bond-donor for preparing ChCl-based DES (ChCl:NE), and a mixture of ChCl:NE (60 wt%) and FeCl3 (0.5 wt%) was utilized for combination pretreatment of CS at 110 ℃ for 50 min. FeCl3/ChCl:NE effectively removed lignin (87.0 %) and xylan (55.9 %) and the enzymatic hydrolysis activity of FeCl3/ChCl:NE-treated CS was 5.5 times that of CS. The reducing sugar yield of pretreated CS was 98.6 %. FeCl3/ChCl:NE significantly disrupted the crystal structure of cellulose in CS and improved the removal of lignin and hemicellulose, enhancing the conversion of cellulose and hemicellulose into monomeric sugars. Overall, this combination of FeCl3 and DES pretreatment methods has high application potential for the biological refining of lignocellulose.


Ferric Compounds , Lignin , Lignin/chemistry , Chlorides , Zea mays/chemistry , Deep Eutectic Solvents , Solvents/chemistry , Biomass , Cellulose/chemistry , Xylans , Hydrolysis
2.
Poult Sci ; 103(2): 103271, 2024 Feb.
Article En | MEDLINE | ID: mdl-38064882

Multiple outbreaks of avian infectious laryngotracheitis (ILT) in chickens, both domestically and internationally, have been directly correlate to widespread vaccine use in affected countries and regions. Phylogenetic and recombination event analyses have demonstrated that avian infectious laryngotracheitis virus (ILTV) field strains are progressively evolving toward the chicken embryo-origin (CEO) vaccine strain. Even with standardized biosecurity measures and effective prevention and control strategies implemented on large-scale farms, continuous ILT outbreaks result in significant economic losses to the poultry industry worldwide. These outbreaks undoubtedly hinder efforts to control and eradicate ILTV in the future. In this study, an ILTV isolate was successfully obtained by laboratory PCR detection and virus isolation from chickens that exhibited dyspnea and depression on a broiler farm in Hubei Province, China. The isolated strain exhibited robust propagation on chorioallantoic membranes of embryonated eggs, but failed to establish effective infection in chicken hepatocellular carcinoma (LMH) cells. Phylogenetic analysis revealed a unique T441P point mutation in the gJ protein of the isolate. Animal experiments confirmed the virulence of this strain, as it induced mortality in 6-wk-old chickens. This study expands current understanding of the epidemiology, genetic variations, and pathogenicity of ILTV isolates circulating domestically, contributing to the elucidate of ILTV molecular basis of pathogenicity and development of vaccine.


Herpesviridae Infections , Herpesvirus 1, Gallid , Poultry Diseases , Viral Vaccines , Chick Embryo , Animals , Chickens , Herpesvirus 1, Gallid/genetics , Virulence , Phylogeny , Ovum , Herpesviridae Infections/epidemiology , Herpesviridae Infections/veterinary , Poultry Diseases/prevention & control
4.
BMC Anesthesiol ; 23(1): 298, 2023 09 04.
Article En | MEDLINE | ID: mdl-37667179

PURPOSE: Transfusing red blood cells promptly corrects anemia and improves tissue oxygenation in around 40% of patients hospitalized in the intensive care unit (ICU) after major surgical operations. This study's goal is to investigate how blood transfusions affect the mortality rates of patients after major surgery who are hospitalized in the ICU. METHODS: Retrospective research was done on recently hospitalized patients who had major procedures in the ICU between October 2020 and February 2022 at the Huanggang Central Hospital of Yangtze University, China. The patients' prognoses at three months were used to classify them as either survivors or deceased. Patient demographic information, laboratory results, and blood transfusion histories were acquired, and the outcomes of the two groups were compared based on the differences. Univariate and multivariate logistic regression analyses were used to examine the prognosis of surgical disease patients first admitted to the ICU. The receiver operating characteristic (ROC) curve was used to evaluate the predictive power of each risk factor. The relationship between transfusion frequency, transfusion modality, and patient outcome was examined using Spearman's correlation analysis. RESULTS: Data from 384 patients was included in the research; of them, 214 (or 55.7%) died within three months of their first stay in the ICU. The death group had higher scores on the Acute Physiology and Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) than the survival group did (all P < 0.05); the death group also had lower scores on the Glasgow Coma Scale, systolic blood pressure, hemoglobin, platelet distribution width, and blood transfusion ratio. Multivariate logistic regression analysis revealed an odds ratio (OR) of 1.654 (1.281-1.989), a 95% confidence interval (CI) of 1.440 (1.207-1.701), and a P value of 0.05 for death in patients undergoing major surgery who were hospitalized to the intensive care unit (ICU). Areas under the ROC curve (AUC) of 0.836, 0.799, and 0.871, respectively, and 95% CIs of 0.796-0.875, 0.755-0.842, and 0.837-0.904, respectively, all P0.05, had significant predictive value for patients initially admitted to the ICU and for APACHE II score > = 12 points, SOFA score > = 6, and blood transfusion. When all three indicators were used jointly to predict a patient's prognosis after major surgery, the accuracy increased to 86.4% (sensitivity) and 100% (specificity). There was a negative correlation between the number of blood transfusions a patient had and their outcome (r = 0.605, P < 0.001) and death (r = 0.698, P < 0.001). CONCLUSION: A higher initial ICU APACHE II score, SOFA score, and a number of blood transfusions were associated with improved survival for patients undergoing major surgical operations. Patients' death rates have increased with the increase in the frequency and variety of blood transfusions.


Hospitalization , Hospitals , Humans , Retrospective Studies , Blood Transfusion , Intensive Care Units
5.
Pharmacology ; 108(4): 344-358, 2023.
Article En | MEDLINE | ID: mdl-37231999

INTRODUCTION: Acid-related inflammatory damage to the esophageal epithelium is a key component in the development of gastroesophageal reflux disease. Melatonin (MT) is considered as a potential therapeutic agent, but its molecular mechanism is unknown. METHODS: The expression of HIF-1α and pyroptosis-related genes (NLRP3, caspase-1, IL-1ß, and IL-18) was analyzed using bioinformatics methods in GSE63401 and validated using quantitative real-time polymerase chain reaction and Western blot in an HEEC inflammation model induced by deoxycholic acid (DCA). Hoechst 33342/PI double staining was used to assess the level of pyroptosis, and the effect of MT treatment was observed. The miRDB, TarBase, miRcode, miRNet, and ENCORI databases were used to predict the long non-coding RNA (lncRNA) targeting HIF-1α and the RNA-binding protein interacting with the lncRNA. RESULTS: The expressions of Moloney leukemia virus 10 (MOV10), lncRNA NEAT1, HIF-1α, and pyroptosis-related genes were upregulated, while the expression of miR-138-5p was downregulated in acidic DCA-induced HEEC inflammation. MOV10 may bind to lncRNA NEAT1 and stabilize its expression, while lncRNA NEAT1 upregulates the expression of HIF-1α by adsorbing miR-138-5p to activate the NLRP3 inflammasome. However, MT pretreatment can significantly inhibit these processes. CONCLUSIONS: MOV10-lncRNA NEAT1/miR-138-5p/HIF-1α/NLRP3 axis plays a crucial role in acid-related esophageal epithelial inflammatory injury, and MT may exert an esophageal protective effect by inhibiting the pathway.


Melatonin , MicroRNAs , RNA, Long Noncoding , MicroRNAs/genetics , MicroRNAs/metabolism , Pyroptosis , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Gene Expression Regulation, Neoplastic , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Cell Proliferation/genetics , Epithelial Cells/metabolism
6.
Nucleic Acids Res ; 51(5): 2485-2495, 2023 03 21.
Article En | MEDLINE | ID: mdl-36807980

The cyclic oligoadenylates (cOAs) act as second messengers of the type III CRISPR immunity system through activating the auxiliary nucleases for indiscriminate RNA degradation. The cOA-degrading nucleases (ring nucleases) provide an 'off-switch' regulation of the signaling, thereby preventing cell dormancy or cell death. Here, we describe the crystal structures of the founding member of CRISPR-associated ring nuclease 1 (Crn1) Sso2081 from Saccharolobus solfataricus, alone, bound to phosphate ions or cA4 in both pre-cleavage and cleavage intermediate states. These structures together with biochemical characterizations establish the molecular basis of cA4 recognition and catalysis by Sso2081. The conformational changes in the C-terminal helical insert upon the binding of phosphate ions or cA4 reveal a gate-locking mechanism for ligand binding. The critical residues and motifs identified in this study provide a new insight to distinguish between cOA-degrading and -nondegrading CARF domain-containing proteins.


CRISPR-Associated Proteins , Clustered Regularly Interspaced Short Palindromic Repeats , Second Messenger Systems , Signal Transduction , Endonucleases/metabolism , Ions/metabolism , CRISPR-Cas Systems , CRISPR-Associated Proteins/metabolism
7.
Journal of Preventive Medicine ; (12): 582-586, 2023.
Article Zh | WPRIM | ID: wpr-980001

@#The incidence rate of vascular dementia is increasing year by year, and there is still no effective treatment at present, so it is very important to reduce the risk of developing vascular dementia. Research shows that diabetes is associated with vascular dementia. Based on the research literature related to diabetes and vascular dementia from January 1995 to April 2023, This article reviews the relationship between diabetes and vascular dementia, pathological mechanism and prevention and control strategies. It is found that diabetes can promote the occurrence and development of vascular dementia by inducing cerebrovascular disease, oxidative stress and inflammatory reaction, using hypoglycemic drugs, removing the incentives of cerebrovascular disease, maintaining the stability of blood-brain barrier and adhering to a healthy lifestyle are the main measures for the prevention and control of vascular dementia at this stage. Future research needs to further explore the mechanism of vascular dementia induced by diabetes, and seek economic and effective prevention targets.

8.
Psychol Res Behav Manag ; 15: 3497-3511, 2022.
Article En | MEDLINE | ID: mdl-36505670

Purpose: As an important channel to search and share information, professional virtual community (PVC) has become one of the main channels for Chinese young netizens to search information and socialize. However, despite many researches on PVC have been conducted in various fields, there is still a lack of researches on young netizens in China, who are in the stage of online social networking booming with countless PVCs but many of them are non-effective. Moreover, there are few studies to explore explicit paths to obtain the effective information sharing or sustainable development of PVC. Therefore, based on this research gap and social cognitive theory, this study explored PVC information sharing among Chinese young netizens combining the external factors and the individual factors, and attempted to obtain the paths to the effective PVC information sharing. Methods: An online survey was conducted through snowball sampling in China, and 407 samples from 15 different PVCs were confirmed. By using fuzzy-set qualitative comparative analysis (fsQCA) with software fs/QCA 3.0, this study attempted to explore the casual configurations that achieve high and non-high effectiveness of PVC information sharing among Chinese young netizens. Results: Three types of equivalent configurations that can achieve high effectiveness of PVC information sharing are obtained; Four types of equivalent configurations that can achieve non-high effectiveness of PVC information sharing are obtained. Furthermore, the findings indicate that the expertise of PVC and challenge-skill balance of members are the primary factors in PVC information sharing. Conclusion: The findings of this study provide that the paths to high and non-high effectiveness of PVC information sharing, which is beneficial to the management and development of PVC. Furthermore, it is helpful for netizens to find and enjoy the PVCs with high quality when they need them. The management of public opinion and how to design web pages to improve the user experience can also be carried out from this perspective.

9.
Plant Signal Behav ; 17(1): 2134672, 2022 Dec 31.
Article En | MEDLINE | ID: mdl-36358009

Phytosulfokines (PSKs) are a class of tyrosine-sulfated pentapeptides. PSK-α, PSK-γ, and PSK-δ are three reported PSK members involved in regulating plant growth, development, and resistance to biotic and abiotic stresses. Here, we reported a novel type of PSK, PSK-ε with the sequence YSO3VYSO3TN, and its precursor proteins (MtPSKε, LjPSKε, and GmPSKε), specifically from legume species. PSK-ε peptide differs from PSK-δ by one amino acid and is close to PSK-δ in the phylogenetic relationship. Expression profile analysis showed that MtPSKε was highly expressed in Medicago truncatula roots, especially in root tips and emerged lateral roots. Application of the synthetic sulfated PSK-ε peptide and overexpression of MtPSKε significantly promoted M. truncatula root elongation and increased lateral root number, probably by inducing cell division and expansion in roots. Furthermore, MtPSKε expression was induced by rhizobia infection and was detected in root nodules including nodule primordia. Both PSK-ε peptide treatment and MtPSKε overexpression significantly increased nodule number in M. truncatula. Taken together, these results demonstrate that PSK-ε, a novel type of phytosulfokine, positively regulates root elongation and formation of lateral root and root nodule in M. truncatula.


Medicago truncatula , Medicago truncatula/genetics , Phylogeny , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Roots , Peptides/metabolism , Gene Expression Regulation, Plant/genetics , Symbiosis
10.
Structure ; 30(5): 743-752.e3, 2022 05 05.
Article En | MEDLINE | ID: mdl-35290797

MUS81 is an important structure-specific endonuclease responsible for the processing of stalled replication forks and recombination intermediates. In human, MUS81 functions by forming complexes with its regulatory subunits EME1 and EME2, playing distinct roles in G2/M and S phases. Although the structures of MUS81-EME1 have been intensively studied, there is no structure information available about MUS81-EME2. Here, we report the crystal structure of MUS81-EME2, which reveals an overall protein fold similar to that of MUS81-EME1 complex. Further biochemical and structural characterization shows that the MUS81-EME1 and MUS81-EME2 complexes are identical in substrate recognition and endonuclease activities in vitro, implying that the distinct cellular roles of the two complexes could arise from temporal controls in cells. Finally, an extensive structure-guided mutagenesis analysis provides implications for the molecular basis of how the MUS81-EME endonucleases recognize various DNA substrates in a structure-selective manner.


DNA-Binding Proteins , Endodeoxyribonucleases , DNA Replication , DNA-Binding Proteins/chemistry , Endodeoxyribonucleases/chemistry , Endonucleases/chemistry , Humans , Substrate Specificity
11.
J Exp Bot ; 73(8): 2698-2713, 2022 04 18.
Article En | MEDLINE | ID: mdl-35137020

Phytosulfokine-α (PSK-α), a tyrosine-sulfated pentapeptide with the sequence YSO3IYSO3TQ, is widely distributed across the plant kingdom and plays multiple roles in plant growth, development, and immune response. Here, we report a novel type of phytosulfokine, PSK-δ, and its precursor proteins (MtPSKδ, LjPSKδ, and GmPSKδ1), specifically from legume species. The sequence YSO3IYSO3TN of sulfated PSK-δ peptide is different from PSK-α at the last amino acid. Expression pattern analysis revealed PSK-δ-encoding precursor genes to be expressed primarily in legume root nodules. Specifically, in Medicago truncatula, MtPSKδ expression was detected in root cortical cells undergoing nodule organogenesis, in nodule primordia and young nodules, and in the apical region of mature nodules. Accumulation of sulfated PSK-δ peptide in M. truncatula nodules was detected by LC/MS. Application of synthetic PSK-δ peptide significantly increased nodule number in legumes. Similarly, overexpression of MtPSKδ in transgenic M. truncatula markedly promoted symbiotic nodulation. This increase in nodule number was attributed to enhanced nodule organogenesis induced by PSK-δ. Additional genetic evidence from the MtPSKδ mutant and RNA interference assays suggested that the PSK-δ and PSK-α peptides function redundantly in regulating nodule organogenesis. These results suggest that PSK-δ, a legume-specific novel type of phytosulfokine, promotes symbiotic nodulation by enhancing nodule organogenesis.


Medicago truncatula , Plant Proteins , Gene Expression Regulation, Plant , Medicago truncatula/metabolism , Peptides/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Root Nodulation/genetics , Root Nodules, Plant/metabolism , Symbiosis/physiology
12.
Appl Biochem Biotechnol ; 194(5): 2061-2076, 2022 May.
Article En | MEDLINE | ID: mdl-35013925

Long non-coding RNAs (lncRNAs) play crucial roles in the development of diabetic nephropathy (DN). Here, we explored the activity and mechanism of MIR503 host gene (MIR503HG) in high glucose (HG)-evoked cytotoxicity in HK-2 cells. MIR503HG, microRNA (miR)-497-5p, and C-C motif chemokine ligand 19 (CCL19) were quantified by quantitative real-time PCR (qRT-PCR) and western blot. The direct relationship between miR-497-5p and MIR503HG or CCL19 was confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Cell viability and apoptosis were evaluated by XTT assay and flow cytometry, respectively. Our data showed that MIR503HG was overexpressed in HG-stimulated HK-2 cells. Knockdown of MIR503HG alleviated HG-evoked cell apoptosis, inflammation, and fibrosis in HK-2 cells. Mechanistically, MIR503HG regulated miR-497-5p expression via a binding site. MIR503HG depletion reduced HG-evoked cell apoptosis, inflammation, and fibrosis in HK-2 cells by up-regulating miR-497-5p. Moreover, miR-497-5p directly targeted and suppressed CCL19. MiR-497-5p-mediated suppression of CCL19 relieved HG-induced cell apoptosis, inflammation, and fibrosis in HK-2 cells. Furthermore, MIR503HG regulated CCL19 expression via miR-497-5p competition. Our findings identify a new MIR503HG/miR-497-5p/CCL19 network in the regulating HG-evoked cell apoptosis, inflammation, and fibrosis in HK-2 cells.


MicroRNAs , RNA, Long Noncoding , Apoptosis/genetics , Chemokine CCL19 , Chemokines , Fibrosis , Glucose/metabolism , Glucose/toxicity , Humans , Inflammation/genetics , Inflammation/metabolism , Ligands , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics
13.
Anim Biotechnol ; 33(6): 1190-1197, 2022 Nov.
Article En | MEDLINE | ID: mdl-33635178

The genetic diversity and population structures of five Chongqing local chicken populations were investigated using by 24 microsatellite markers. Results revealed that the mean number of alleles (NA) ranged from 7.08 (Daninghe chicken, DN) to 8.46 (Nanchuan chicken, NC). The highest observed heterozygosity (HO) and expected heterozygosity (HE) were observed in DN (HO = 0.7252; HE = 0.7409) and the lowest HO and HE were observed in XS (Xiushan native chicken [XS], HO = 0.5910 and HE = 0.6697). The inbreeding coefficient (FIS) within population ranged from 0.022 (DN) to 0.119 (XS). Among the 24 microsatellite markers, four loci (MCW0111, MCW0016, ADL0278, and MCW0104) deviated from the Hardy-Weinberg equilibrium in all the studied populations. The results of population polygenetic analysis based on Nei's genetic distance and STRUCTURE software showed that the clustering of the five populations was incomplete consistent with geographical distribution. Moreover, a large number of gene flows were widespread among different populations, suggesting that genetic material exchanges occurred due to human activities and migration which was also verified by PCoA. In summary, this study preliminarily showed that Chongqing local chicken populations had rich genetic diversity and remarkable genetic divergence, but still high risk in conversion. These findings would be useful to the management of conservation strategies and the utilization of local chicken populations in further.


Chickens , Genetic Variation , Humans , Animals , Chickens/genetics , Phylogeny , Genetic Variation/genetics , Microsatellite Repeats/genetics , Alleles
14.
Nature ; 600(7887): 59-63, 2021 12.
Article En | MEDLINE | ID: mdl-34666339

Mare volcanics on the Moon are the key record of thermo-chemical evolution throughout most of lunar history1-3. Young mare basalts-mainly distributed in a region rich in potassium, rare-earth elements and phosphorus (KREEP) in Oceanus Procellarum, called the Procellarum KREEP Terrane (PKT)4-were thought to be formed from KREEP-rich sources at depth5-7. However, this hypothesis has not been tested with young basalts from the PKT. Here we present a petrological and geochemical study of the basalt clasts from the PKT returned by the Chang'e-5 mission8. These two-billion-year-old basalts are the youngest lunar samples reported so far9. Bulk rock compositions have moderate titanium and high iron contents  with KREEP-like rare-earth-element and high thorium concentrations. However, strontium-neodymium isotopes indicate that these basalts were derived from a non-KREEP mantle source. To produce the high abundances of rare-earth elements and thorium, low-degree partial melting and extensive fractional crystallization are required. Our results indicate that the KREEP association may not be a prerequisite for young mare volcanism. Absolving the need to invoke heat-producing elements in their source implies a more sustained cooling history of the lunar interior to generate the Moon's youngest melts.

15.
Asian J Pharm Sci ; 16(3): 265-279, 2021 May.
Article En | MEDLINE | ID: mdl-34276818

The penetration behavior of topical substances in the skin not only relates to the transdermal delivery efficiency but also involves the safety and therapeutic effect of topical products, such as sunscreen and hair growth products. Researchers have tried to illustrate the transdermal process with diversified theories and technologies. Directly observing the distribution of topical substances on skin by characteristic imaging is the most convincing approach. Unfortunately, fluorescence labeling imaging, which is commonly used in biochemical research, is limited for transdermal research for most topical substances with a molecular mass less than 500 Da. Label-free imaging technologies possess the advantages of not requiring any macromolecular dyes, no tissue destruction and an extensive substance detection capability, which has enabled rapid development of such technologies in recent years and their introduction to biological tissue analysis, such as skin samples. Through the specific identification of topical substances and endogenous tissue components, label-free imaging technologies can provide abundant tissue distribution information, enrich theoretical and practical guidance for transdermal drug delivery systems. In this review, we expound the mechanisms and applications of the most popular label-free imaging technologies in transdermal research at present, compare their advantages and disadvantages, and forecast development prospects.

16.
Int J Pharm ; 597: 120328, 2021 Mar 15.
Article En | MEDLINE | ID: mdl-33540013

During the occurring of cutaneous trauma, increasing oxidative stress response in wound site retards the progress of proliferation phase, impeding sequent efficient wound repair. At the same time, high-quality healing also requires adequate new blood vessels in order to furnish the wound site with a nutrient and oxygen-sufficient environment. Here we synthesized a novel hyaluronic acid (HA) material modified with a peroxidation inhibitor 2,2,6,6-tetramethylpiperidinyloxy (ATEMPO) for prevention of excessive reactive oxygen species (ROS) and promotion of angiogenesis after full-thickness skin excision in rats. Amines in ATEMPO attaching with carbonyls in HA chains was fabricated through N-acylation. The HA-g-TEMPO exerted a ROS-scavenging and angiogenesis-promoting function in vitro. In acute wound rat model, the wound closure efficacy was significantly improved to almost 55% at day 6 in comparison to 49% of HA, and wound sites in initial wound phase was also narrowed down sharply. Moreover, initially formed blood vessels were found in wound sites, further proved the angiogenesis-promoting function of HA-g-TEMPO. More interestingly, wound sites demonstrated an exciting regenerative healing effect which was characterized by marked skin appendages as well as reduced scarring. Therefore, this strategy showed a promising future that could be considered as a reliable and effective method to cutaneous wound healing.


Hyaluronic Acid , Wound Healing , Animals , Cyclic N-Oxides , Rats , Reactive Oxygen Species , Skin
17.
Microb Cell Fact ; 20(1): 11, 2021 Jan 09.
Article En | MEDLINE | ID: mdl-33422055

BACKGROUND: D-Amino acids are increasingly used as building blocks to produce pharmaceuticals and fine chemicals. However, establishing a universal biocatalyst for the general synthesis of D-amino acids from cheap and readily available precursors with few by-products is challenging. In this study, we developed an efficient in vivo biocatalysis system for the synthesis of D-amino acids from L-amino acids by the co-expression of membrane-associated L-amino acid deaminase obtained from Proteus mirabilis (LAAD), meso-diaminopimelate dehydrogenases obtained from Symbiobacterium thermophilum (DAPDH), and formate dehydrogenase obtained from Burkholderia stabilis (FDH), in recombinant Escherichia coli. RESULTS: To generate the in vivo cascade system, three strategies were evaluated to regulate enzyme expression levels, including single-plasmid co-expression, double-plasmid co-expression, and double-plasmid MBP-fused co-expression. The double-plasmid MBP-fused co-expression strain Escherichia coli pET-21b-MBP-laad/pET-28a-dapdh-fdh, exhibiting high catalytic efficiency, was selected. Under optimal conditions, 75 mg/mL of E. coli pET-21b-MBP-laad/pET-28a-dapdh-fdh whole-cell biocatalyst asymmetrically catalyzed the stereoinversion of 150 mM L-Phe to D-Phe, with quantitative yields of over 99% ee in 24 h, by the addition of 15 mM NADP+ and 300 mM ammonium formate. In addition, the whole-cell biocatalyst was used to successfully stereoinvert a variety of aromatic and aliphatic L-amino acids to their corresponding D-amino acids. CONCLUSIONS: The newly constructed in vivo cascade biocatalysis system was effective for the highly selective synthesis of D-amino acids via stereoinversion.


Amino Acid Oxidoreductases/metabolism , Amino Acids/metabolism , Aminohydrolases/metabolism , Formate Dehydrogenases/metabolism , Biocatalysis , Burkholderia/enzymology , Clostridiales/enzymology , Proteus mirabilis/enzymology , Stereoisomerism , Substrate Specificity
18.
Sensors (Basel) ; 20(18)2020 Sep 17.
Article En | MEDLINE | ID: mdl-32957619

Accurate analysis using a simple and rapid procedure is always the most important pursuit of analytical chemists. In this study, a new sample preparation procedure, namely the shaker cup (SH) method, was designed and compared with two sample preparation procedures, commonly used in the laboratory, from three aspects: homogeneity of the sample-flux mixture, potential for sample contamination, and sample preparation time. For the three methods, a set of 54 certified reference materials (CRMs) was used to establish the calibration curves, while another set of 19 CRMs was measured to validate the results. In the calibration procedures, the matrix effects were corrected using the theoretical alpha coefficient method combined with the experimental coefficient method. The data of the major oxides (SiO2, TiO2, Al2O3, TFe2O3, MnO, MgO, CaO, Na2O, K2O, and P2O5) and minor elements (Cr, Cu, Ba, Ni, Sr, V, Zr, and Zn) obtained by wavelength dispersive X-ray fluorescence spectroscopy (WD-XRF) were compared using two derivative equations based on the findings by Laurence Whitty-Léveillé. The results revealed that the WD-XRF measured values using the SH method best agreed with the values recommended in the literature.

19.
Int J Pharm ; 588: 119722, 2020 Oct 15.
Article En | MEDLINE | ID: mdl-32805639

Topical administration is a promising clinical strategy to avoid serious gastrointestinal adverse reactions of loxoprofen sodium (LOX), a new non-steroidal anti-inflammatory drug. Small molecule organic acids had been reported with the ability of promoting transdermal rate of several drugs. In this article, the effect of small molecule organic acids on the transdermal delivery of LOX was studied, and the possible mechanism was also explored by Fourier infrared spectroscopy, differential scanning calorimetry, tape stripping, etc. The results showed that lactic acid and fumaric acid could significantly increase the penetration rate of LOX and reduce time lag even without the help of acidic environment. The preliminary mechanism investigation inferred that fumaric acid could increase LOX's distribution in stratum corneum and might change its complexation state, but had little effect on the drug structure and skin's lipids and proteins configuration. The topical LOX gel using fumaric acid as penetration enhancer had higher transdermal rate, significant anti-inflammatory effect and no obvious skin irritation. This study proved the promising application of small molecule organic acids in transdermal enhancing and provided a potential strategy for transdermal delivery of LOX combined with fumaric acid.


Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Fumarates/pharmacology , Inflammation/prevention & control , Phenylpropionates/administration & dosage , Skin Absorption/drug effects , Skin/drug effects , Administration, Cutaneous , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Carrageenan , Disease Models, Animal , Female , Gels , Inflammation/chemically induced , Lactic Acid/pharmacology , Male , Phenylpropionates/chemistry , Phenylpropionates/metabolism , Rabbits , Rats, Sprague-Dawley , Skin/metabolism , Swine , Swine, Miniature , Time Factors
20.
Biochem Biophys Res Commun ; 523(1): 66-71, 2020 02 26.
Article En | MEDLINE | ID: mdl-31831172

Leguminous root nodules specifically induced by rhizobium species fix nitrogen gas to gain nitrogen sources, which is important in sustainable agriculture and ecological balance. Several peptide signals are reported to be involved in regulation of legume nodule number and development. There are fifteen genes coding Root Meristem Growth Factor (RGF) peptide in Medicago truncatula, herein we find the expression of MtRGF3 is significantly induced by Sinorhizobium meliloti with production of Nod factors. The gene promoter is active in nodule primordia, young nodules and the meristem region of mature nodules. Knock-down (RNAi) roots of the gene (MtRGF3-RNAi) formed more root nodules than the empty vector control, and the nodule number decreased in MtRGF3-overexpressing (MtRGF3-OX) roots. Exogenous addition of the synthesized peptide significantly promoted primary root growth and inhibited lateral root emergence, in addition, the peptide application reduced the number of infection threads, nodule primordia and root nodules of M. truncatula. We also found that tyrosine sulfation determines the biological activity of MtRGF3 functioning in nodulation process, and MtRGF3 peptide negatively regulates nodulation in a dosage manner. These results demonstrate that the MtRGF3 peptide is a novel regulator during nodulation of Medicago trucatula.


Medicago truncatula/metabolism , Peptides/metabolism , Plant Proteins/metabolism , Transcription Factors/metabolism , Medicago truncatula/genetics , Peptides/genetics , Plant Proteins/genetics , Plant Root Nodulation/genetics , Plant Roots/metabolism , Sinorhizobium meliloti/metabolism , Transcription Factors/genetics
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