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1.
Sci Total Environ ; 912: 169370, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38104825

ABSTRACT

Catchment-scale understanding of water and contaminant fluxes through all pathways is essential to address land use and climate change impacts on freshwater. However, few options exist to obtain this understanding for the many catchments worldwide for which streamflow and low-frequency water chemistry, but little other data exists. We applied the Bayesian chemistry-assisted hydrograph separation and load partitioning model (BACH) to 47 catchments with widely differing characteristics. As BACH relies on concentration differences between pathways, chemodynamic behaviour of a water constituent indicates its likely suitability as tracer. Typical tracers (e.g. silica, chloride) were unavailable, but Electrical Conductivity and a few monitored nutrients proved chemodynamic in most catchments. Using one of two tracer combinations (Total Nitrogen + Electrical Conductivity, Total Nitrogen + Total Phosphorus) allowed in 85 % of the catchments to estimate streamflow contributions by near-surface (NS), shallow groundwater (SGW), and deep groundwater (DGW) pathways and pathway-specific tracer concentrations and yields with acceptable confidence. In 46 catchments, at least two pathways contributed ≥20 % of the streamflow, and all three ≥20 % in 12 catchments, cautioning against the notion of a single 'dominant' pathway. In contrast to hydrometric hydrograph separation, BACH allows differentiation between 'young' (NS + SGW) and 'old' (DGW) water, which is crucial for the understanding of pollution in catchments with strong temporal gradients in land use intensity. Consistent with generally increasing land use intensity, and groundwater denitrification occurring in some catchments, Total Nitrogen (TN) concentrations were in most catchments higher in NS and SGW compared to DGW. In most catchments, the greatest fraction of the TN yield was conveyed by SGW (≈ 40-90 %). Exceptions were wet and hilly catchments under bush, where the NS transferred most of the very low yields, and three young volcanic catchments where the DGW transferred the majority of the yield due to particularly high DGW flow contributions.

2.
Biotechnol Biofuels Bioprod ; 16(1): 193, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38093358

ABSTRACT

BACKGROUND: Agar is used as a gelling agent that possesses a variety of biological properties; it consists of the polysaccharides agarose and porphyrin. In addition, the monomeric sugars generated after agar hydrolysis can be functionalized for use in biorefineries and biofuel production. The main objective of this study was to develop a sustainable agar hydrolysis process for bioethanol production using nanotechnology. Peroxidase-mimicking Fe3O4-MNPs were applied for agar degradation to generate agar hydrolysate-soluble fractions amenable to Saccharomyces cerevisiae and Escherichia coli during fermentation. RESULTS: Fe3O4-MNP-treated (Fe3O4-MNPs, 1 g/L) agar exhibited 0.903 g/L of reducing sugar, which was 21-fold higher than that of the control (without Fe3O4-MNP-treated). Approximately 0.0181% and 0.0042% of ethanol from 1% of agar was achieved using Saccharomyces cerevisiae and Escherichia coli, respectively, after process optimization. Furthermore, different analytical techniques (FTIR, SEM, TEM, EDS, XRD, and TGA) were applied to validate the efficiency of Fe3O4-MNPs in agar degradation. CONCLUSIONS: To the best of our knowledge, Fe3O4-MNP-treated agar degradation for bioethanol production through process optimization is a simpler, easier, and novel method for commercialization.

3.
bioRxiv ; 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37790498

ABSTRACT

KRAS G12C inhibitor (G12Ci) has produced encouraging, albeit modest and transient, clinical benefit in pancreatic ductal adenocarcinoma (PDAC). Identifying and targeting resistance mechanisms to G12Ci treatment is therefore crucial. To better understand the tumor biology of the KRAS G12C allele and possible bypass mechanisms, we developed a novel autochthonous KRAS G12C -driven PDAC model. Compared to the classical KRAS G12D PDAC model, the G12C model exhibit slower tumor growth, yet similar histopathological and molecular features. Aligned with clinical experience, G12Ci treatment of KRAS G12C tumors produced modest impact despite stimulating a 'hot' tumor immune microenvironment. Immunoprofiling revealed that CD24, a 'do-not-eat-me' signal, is significantly upregulated on cancer cells upon G12Ci treatment. Blocking CD24 enhanced macrophage phagocytosis of cancer cells and significantly sensitized tumors to G12Ci treatment. Similar findings were observed in KRAS G12D -driven PDAC. Our study reveals common and distinct oncogenic KRAS allele-specific biology and identifies a clinically actionable adaptive mechanism that may improve the efficacy of oncogenic KRAS inhibitor therapy in PDAC. Significance: Lack of faithful preclinical models limits the exploration of resistance mechanisms to KRAS G12C inhibitor in PDAC. We generated an autochthonous KRAS G12C -driven PDAC model, which revealed allele-specific biology of the KRAS G12C during PDAC development. We identified CD24 as an actionable adaptive mechanisms in cancer cells induced upon KRAS G12C inhibition and blocking CD24 sensitizes PDAC to KRAS inhibitors in preclinical models.

4.
Biotechnol Appl Biochem ; 70(6): 2136-2149, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37735977

ABSTRACT

Cell-free protein synthesis (CFPS) system is an innovative technology with a wide range of potential applications that could challenge current thinking and provide solutions to environmental and health issues. CFPS system has been demonstrated to be a successful way of producing biomolecules in a variety of applications, including the biomedical industry. Although there are still obstacles to overcome, its ease of use, versatility, and capacity for integration with other technologies open the door for it to continue serving as a vital instrument in synthetic biology research and industry. In this review, we mainly focus on the cell-free based platform for various product productions. Moreover, the challenges in the bio-therapeutic aspect using cell-free systems and their future prospective for the improvement and sustainability of the cell free systems.


Subject(s)
Biotechnology , Protein Biosynthesis , Cell-Free System , Biotechnology/methods , Synthetic Biology , Industry
5.
Microbiol Spectr ; 11(4): e0160623, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37378523

ABSTRACT

Tuberculosis (TB) is an ongoing threat to public health, and furthermore, the incidence of infections by nontuberculous mycobacteria (NTM), whose symptoms are not distinguishable from TB, is increasing globally, thus indicating a need for accurate diagnostics for patients with suspected mycobacterial infections. Such diagnostic strategies need to include two steps, (i) detecting the mycobacterial infections and, if the case is an NTM infection, (ii) identifying the causative NTM pathogen. To eliminate a false-positive TB diagnosis for a host vaccinated by the bacillus Calmette-Guérin (BCG) strain of Mycobacterium bovis, a new target specific for M. tuberculosis species was selected, together with the species-specific targets for the six dominant NTM species of clinical importance, i.e., M. intracellulare, M. avium, M. kansasii, M. massiliense, M. abscessus, and M. fortuitum. Using sets of primers and probes, a two-step real-time multiplex PCR method was designed. The diagnostic performance was assessed by using a total of 1,772 clinical specimens from patients with suspected TB or NTM infection. A total of 69.4% of M. tuberculosis and 28.8% of NTM infections were positive for the primary step of the real-time PCR corresponding to the culture within 10 weeks, and mycobacterial species of 75.5% of the NTM-positive cases were identified by the secondary step. The two-step method described herein presented promising results and similar diagnostic sensitivity and specificity to commercially available real-time PCR kits for detecting TB and NTM infections. The method also enabled the identification of mycobacterial species in three-quarters of NTM infection cases, thus providing a better treatment strategy. IMPORTANCE Tuberculosis (TB) is an ongoing threat to public health. In addition, infection by nontuberculous mycobacteria (NTM) is a nonnegligible issue for global public health, with increasing incidences. Since the antimicrobial treatment strategy needs to be differed by the causative pathogen, a rapid and accurate diagnostic method is necessary. In this study, we developed a two-step molecular diagnostic method using clinical specimens of TB and NTM infection-suspected patients. The diagnostic power of the new method using the novel target was similar to the widely used TB detection kit, and, among the NTM-positive specimens, three-quarters of the NTM species were able to be identified. This simple and powerful method will be useful as it is, and it could be applied easily to a point-of-care diagnostic apparatus for better application to patients, especially those living in developing countries.


Subject(s)
Mycobacterium Infections, Nontuberculous , Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis , Humans , Real-Time Polymerase Chain Reaction/methods , Tuberculosis/diagnosis , Tuberculosis/epidemiology , Tuberculosis/microbiology , Mycobacterium Infections, Nontuberculous/diagnosis , Mycobacterium Infections, Nontuberculous/epidemiology , Mycobacterium Infections, Nontuberculous/microbiology , Nontuberculous Mycobacteria/genetics , Mycobacterium tuberculosis/genetics
6.
Microb Cell Fact ; 22(1): 98, 2023 May 11.
Article in English | MEDLINE | ID: mdl-37170276

ABSTRACT

BACKGROUND: Palifermin (trade name Kepivance®) is an amino-terminally truncated recombinant human keratinocyte growth factor 1 (KGF-1) with 140 residues that has been produced using Escherichia coli to prevent and treat oral mucositis following radiation or chemotherapy. In this study, an amino-terminally shortened KGF-1 variant with 135 residues was produced and purified in E. coli, and its cell proliferation activity was evaluated. RESULTS: We expressed soluble KGF-1 fused to thioredoxin (TRX) in the cytoplasmic fraction of E. coli to improve its production yield. However, three N-truncated forms (KGF-1 with 140, 138, and 135 residues) were observed after the removal of the TRX protein from the fusion form by cleavage of the human enterokinase light chain C112S (hEKL C112S). The shortest KGF-1 variant, with 135 residues, was expressed by fusion with TRX via the hEKL cleavage site in E. coli and purified at high purity (> 99%). Circular dichroism spectroscopy shows that purified KGF-1135 had a structure similar to that of the KGF-1140 as a random coiled form, and MCF-7 cell proliferation assays demonstrate its biological activity. CONCLUSIONS: We identified variations in N-terminus-truncated KGF-1 and selected the most stable form. Furthermore, by a simple two-step purification, highly purified KGF-1135 was obtained that showed biological activity. These results demonstrate that KGF-1135 may be considered an alternative protein to KGF-1.


Subject(s)
Escherichia coli , Fibroblast Growth Factor 7 , Humans , Fibroblast Growth Factor 7/genetics , Fibroblast Growth Factor 7/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism
7.
Physiol Plant ; 175(2): e13909, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37026423

ABSTRACT

Pathogenesis-related (PR) signaling plays multiple roles in plant development under abiotic and biotic stress conditions and is regulated by a plethora of plant physiological as well as external factors. Here, our study was conducted to evaluate the role of an ACC deaminase-producing endophytic bacteria in regulating ethylene-induced PR signaling in red pepper plants under salt stress. We also evaluated the efficiency of the bacteria in down-regulating the PR signaling for efficient colonization and persistence in the plant endosphere. We used a characteristic endophyte, Methylobacterium oryzae CBMB20 and its ACC deaminase knockdown mutant (acdS- ). The wild-type M. oryzae CBMB20 was able to decrease ethylene emission by 23% compared to the noninoculated and acdS- M. oryzae CBMB20 inoculated plants under salt stress. The increase in ethylene emission resulted in enhanced hydrogen peroxide concentration, phenylalanine ammonia-lyase activity, ß-1,3 glucanase activity, and expression profiles of WRKY, CaPR1, and CaPTI1 genes that are typical salt stress and PR signaling factors. Furthermore, the inoculation of both the bacterial strains had shown induction of PR signaling under normal conditions during the initial inoculation period. However, wild-type M. oryzae CBMB20 was able to down-regulate the ethylene-induced PR signaling under salt stress and enhance plant growth and stress tolerance. Collectively, ACC deaminase-producing endophytic bacteria down-regulate the salt stress-mediated PR signaling in plants by regulating the stress ethylene emission levels and this suggests a new paradigm in efficient colonization and persistence of ACC deaminase-producing endophytic bacteria for better plant growth and productivity.


Subject(s)
Capsicum , Capsicum/metabolism , Salt Stress , Ethylenes/metabolism , Bacteria/metabolism
8.
J Microbiol ; 61(4): 411-421, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37071293

ABSTRACT

Toxin-antitoxin (TA) systems are widespread in bacteria and archaea plasmids and genomes to regulate DNA replication, gene transcription, or protein translation. Higher eukaryotic and prokaryotic nucleotide-binding (HEPN) and minimal nucleotidyltransferase (MNT) domains are prevalent in prokaryotic genomes and constitute TA pairs. However, three gene pairs (MTH304/305, 408/409, and 463/464) of Methanothermobacter thermautotropicus ΔH HEPN-MNT family have not been studied as TA systems. Among these candidates, our study characterizes the MTH463/MTH464 TA system. MTH463 expression inhibited Escherichia coli growth, whereas MTH464 did not and blocked MTH463 instead. Using site-directed MTH463 mutagenesis, we determined that amino acids R99G, H104A, and Y106A from the R[ɸX]4-6H motif are involved with MTH463 cell toxicity. Furthermore, we established that purified MTH463 could degrade MS2 phage RNA, whereas purified MTH464 neutralized MTH463 activity in vitro. Our results indicate that the endonuclease toxin MTH463 (encoding a HEPN domain) and its cognate antitoxin MTH464 (encoding the MNT domain) may act as a type II TA system in M. thermautotropicus ΔH. This study provides initial and essential information studying TA system functions, primarily archaea HEPN-MNT family.


Subject(s)
Antitoxins , Eukaryota , Nucleotidyltransferases/metabolism , Antitoxins/genetics , Prokaryotic Cells , Methanobacteriaceae/genetics , Bacterial Proteins/metabolism
9.
Int J Biol Macromol ; 236: 123997, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36907298

ABSTRACT

Petrochemical-based plastics are hardly biodegradable and a major cause of environmental pollution, and polyhydroxybutyrate (PHB) is attracting attention as an alternative due to its similar properties. However, the cost of PHB production is high and is considered the greatest challenge for its industrialization. Here, crude glycerol was used as a carbon source for more efficient PHB production. Among the 18 strains investigated, Halomonas taeanenisis YLGW01 was selected for PHB production due to its salt tolerance and high glycerol consumption rate. Furthermore, this strain can produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3 HV)) with 17 % 3 HV mol fraction when a precursor is added. PHB production was maximized through medium optimization and activated carbon treatment of crude glycerol, resulting in 10.5 g/L of PHB with 60 % PHB content in fed-batch fermentation. Physical properties of the produced PHB were analyzed, i.e., weight average molecular weight (6.8 × 105), number average molecular weight (4.4 × 105), and the polydispersity index (1.53). In the universal testing machine analysis, the extracted intracellular PHB showed a decrease in Young's modulus, an increase in Elongation at break, greater flexibility than authentic film, and decreased brittleness. This study confirmed that YLGW01 is a promising strain for industrial PHB production using crude glycerol.


Subject(s)
Glycerol , Halomonas , Polyesters , Plastics , Hydroxybutyrates
10.
Article in English | MEDLINE | ID: mdl-36901435

ABSTRACT

This study examined the relationship between the receipt of COVID-19 child tax credit and adult mental health problems in the United States, and we explored whether and the extent to which a wide range of spending patterns of the credit-15 patterns regarding basic necessities, child education, and household expenditure-mediated the relationship. We used COVID-19-specialized data from the U.S. Census Bureau's Household Pulse Survey, a representative population sample (N = 98,026) of adult respondents (18 and older) who participated between 21 July 2021 and 11 July 2022. By conducting mediation analyses with logistic regression, we found relationships between the credit and lower levels of anxiety (odds ratio [OR] = 0.914; 95% confidence interval [CI] = 0.879, 0.952). The OR was substantially mediated by spending on basic necessities such as food and housing costs (proportion mediated = 46% and 44%, respectively). The mediating role was relatively moderate in the case of spending on child education and household expenditure. We also found that spending the credit on savings or investments reduces the effect of the child tax credit on anxiety (-40%) while donations or giving to family were not a significant mediator. Findings on depression were consistent with anxiety. The child tax credit-depression relationships were substantially mediated by spending on food and housing (proportion mediated = 53% and 70%). These mediation analyses suggested that different patterns of credit spending are important mediators of the relationship between the receipt of the child tax credit and mental illnesses. Public health approaches to improve adult mental health during and after the COVID-19 pandemic need to consider the notable mediating role of spending patterns.


Subject(s)
COVID-19 , Mental Health , Adult , Humans , Child , United States , Pandemics , Censuses , Mediation Analysis
11.
Protein Expr Purif ; 204: 106229, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36641112

ABSTRACT

Recombinant human keratinocyte growth factor 2 (KGF-2), also known as repifermin, is used in various therapeutic applications. However, KGF-2 production has not been optimized for facilitating large-scale production. Therefore, we attempted to attain high-level production of bioactive KGF-2. KGF-2 was fused with 6HFh8 (6HFh8-KGF-2) at the tobacco etch virus protease cleavage site. The 6HFh8-KGF-2 was expressed in Escherichia coli with high expression levels of approximately 33% and 20% of soluble protein in flask culture and 5 L fermentation, respectively. 6HFh8-KGF-2 was purified via nickel affinity chromatography. To maintain a stable form of KGF-2, the conditions of the cleavage reaction were optimized based on the isoelectric point. KGF-2 was purified via ion-exchange chromatography to high purity (>99%) with an optimal purification yield (91%). Circular dichroism spectroscopy demonstrated that purified KGF-2 had a secondary structure and thermal stability similar to that of commercial KGF-2. Bioactivity assays indicated that purified KGF-2 could induce MCF-7 cell proliferation in the same manner as commercial KGF-2. These results demonstrate that bioactive KGF-2 was overexpressed in E. coli and purified to high quality. Our findings indicated that bioactive KGF-2 can be produced in large quantities in E. coli.


Subject(s)
Escherichia coli , Humans , Escherichia coli/genetics , Escherichia coli/metabolism , Fibroblast Growth Factor 10/metabolism , MCF-7 Cells , Fermentation
12.
J Hous Built Environ ; : 1-31, 2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36624828

ABSTRACT

This article describes racial and ethnic differences in mortgage payment difficulties during the COVID-19 pandemic and examines whether disparities exist in the benefits of the unemployment insurance (UI) program. The sample consisted of 80,797 jobless mortgage borrowers who received or waited for UI benefits between August 2020 and May 2022. Considering individual- and state-level variables in multilevel logistic regressions, we examined rates of mortgage delay in the last month and payment concerns about the next month by racial and ethnic group. Minority borrowers were more likely to have a difficulty in paying mortgage than White borrowers. UI recipients-regardless of race and ethnicity-were less likely to experience mortgage difficulties, but the positive unemployment benefit was reduced disproportionately among Blacks. Blacks were also at a higher risk of mortgage difficulties compounded by other pandemic-induced hardships-loss of household, lack of food, and mental illness-even after the receipt of UI. Findings on the intersection between race and ethnicity and UI suggest that pandemic policy interventions should be race conscious and consider the longstanding and systematic barriers experienced by minority mortgage borrowers. Supplementary Information: The online version contains supplementary material available at 10.1007/s10901-022-10006-w.

13.
Int J Mol Sci ; 23(21)2022 Nov 04.
Article in English | MEDLINE | ID: mdl-36362312

ABSTRACT

This study aimed to develop a corneal epithelial injury model in zebrafish (Danio rerio) and investigate the effectiveness of polydeoxyribonucleotide (PDRN) treatment on in vivo corneal epithelial regeneration and wound healing. Chemical injury to zebrafish cornea was produced by placing a small cotton swab containing 3% acetic acid solution. PDRN treatment was performed by immersing corneal-injured zebrafish in water containing PDRN (2 mg/mL) for 10 min at 0, 24, 48, and 72 h post-injury (hpi). The level of corneal healing was evaluated by fluorescein staining, histological examination, transcriptional profiling, and immunoblotting techniques. Fluorescein staining results demonstrate that PDRN treatment significantly (p < 0.05) reduced the wounded area of the zebrafish eye at 48 and 72 hpi, suggesting that PDRN may accelerate the corneal re-epithelialization. Histopathological evaluation revealed that injured corneal epithelial cells were re-organized at 72 hpi upon PDRN treatment with increased goblet cell density and size. Moreover, transcriptional analysis results demonstrate that PDRN treatment induced the mRNA expression of adora2ab (6.3-fold), pax6a (7.8-fold), pax6b (29.3-fold), klf4 (7.3-fold), and muc2.1 (5.0-fold) after the first treatment. Besides, tnf-α (2.0-fold) and heat-shock proteins (hsp70; 2.8-fold and hsp90ab1; 1.6-fold) have modulated the gene expression following the PDRN treatment. Immunoblotting results convincingly confirmed the modulation of Mmp-9, Hsp70, and Tnf-α expression levels upon PDRN treatment. Overall, our corneal injury model in zebrafish allows for understanding the morphological and molecular events of corneal epithelial healing, and ophthalmic responses for PDRN treatment following acid injury in zebrafish.


Subject(s)
Corneal Injuries , Polydeoxyribonucleotides , Animals , Polydeoxyribonucleotides/pharmacology , Polydeoxyribonucleotides/therapeutic use , Zebrafish , Tumor Necrosis Factor-alpha/pharmacology , Corneal Injuries/drug therapy , Corneal Injuries/metabolism , Wound Healing , Cornea/metabolism , Fluoresceins/pharmacology
14.
Cities ; 131: 104003, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36168406

ABSTRACT

While the overall level of food insecurity in the United States has remained stable during the COVID-19 pandemic, certain individuals and regions have fared worse than others. This study examines state-level variables affecting individual- and household-level food insecurity during the recent two years of the pandemic beginning in 2020 by utilizing the Household Pulse Survey, a new nationally representative dataset developed by the United States Census Bureau. The results of this study suggest a set of statewide factors, such as pandemic-driven market conditions, COVID-19 prevalence, and the implementation of federal programs, are associated with the level of food insecurity that individuals have experienced during the pandemic over the past two years. The associations varied by household income levels, indicating a strong relationship between higher-income households and market conditions, as well as the importance of federal programs and state policies in alleviating food insecurity among lower-income households. The food insecurity indices also overlapped with different socioeconomic and health hardships caused by the pandemic, such as employment income loss, housing instability, and mental health problems. The findings of this study highlight state-level contexts, particularly the role of state governments, in responding to pandemic-related food insecurity.

15.
J Biotechnol ; 359: 21-28, 2022 Nov 20.
Article in English | MEDLINE | ID: mdl-36152769

ABSTRACT

Using lignocellulosic biomass is immensely beneficial for the economical production of biochemicals. However, utilizing mixed sugars from lignocellulosic biomass is challenging because of bacterial preference for specific sugar such as glucose. Although previous studies have attempted to overcome this challenge, no studies have been reported on isobutanol production from mixed sugars in the Escherichia coli strain. To overcome catabolite repression of xylose and produce isobutanol using mixed sugars, we applied the combination of three strategies: (1) deletion of the gene for the glucose-specific transporter of the phosphotransferase system (ptsG); (2) overexpression of glucose kinase (glk) and glucose facilitator protein (glf); and (3) overexpression of the xylose regulator (xylR). xylR gene overexpression resulted in 100% of glucose and 82.5% of xylose consumption in the glucose-xylose mixture (1:1). Moreover, isobutanol production increased by 192% in the 1:1 medium, equivalent to the amount of isobutanol produced using only glucose. These results indicate the effectiveness of xylR overexpression in isobutanol production. Our findings demonstrated various strategies to overcome catabolite repression for a specific product, isobutanol. The present study suggests that the selected strategy in E. coli could overcome the major challenge using lignocellulosic biomass to produce isobutanol.


Subject(s)
Catabolite Repression , Escherichia coli Proteins , Xylose/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Glucose/metabolism , Sugars/metabolism , Phosphotransferases/genetics , Fermentation , Transcription Factors/genetics , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism
16.
Sci Rep ; 12(1): 14944, 2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36056125

ABSTRACT

Phytotoxicity is caused by the interaction between plants and a chemical substance, which can cause critical damage to plants. Understanding the molecular mechanism underlying plant-chemical interactions is important for managing pests in crop fields and avoiding plant phytotoxicity by insecticides. The genomic region responsible for sensitivity to phytotoxicity of etofenprox (PE), controlled by a single dominant gene, was detected by constructing high density genetic map using recombination inbred lines (RILs) in soybean. The genomic region of ~ 80 kbp containing nine genes was identified on chromosome 16 using a high-throughput single nucleotide polymorphism (SNP) genotyping system using two different RIL populations. Through resequencing data of 31 genotypes, nonsynonymous SNPs were identified in Glyma.16g181900, Glyma.16g182200, and Glyma.16g182300. The genetic variation in Glyma.16g182200, encoding glycosylphosphatidylinositol-anchored protein (GPI-AP), caused a critical structure disruption on the active site of the protein. This structural variation of GPI-AP may change various properties of the ion channels which are the targets of pyrethroid insecticide including etofenprox. This is the first study that identifies the candidate gene and develops SNP markers associated with PE. This study would provide genomic information to understand the mechanism of phytotoxicity in soybean and functionally characterize the responsive gene.


Subject(s)
Glycine max , Pyrethrins , Chromosome Mapping , Genes, Plant , Polymorphism, Single Nucleotide , Pyrethrins/metabolism , Pyrethrins/toxicity , Glycine max/genetics , Glycine max/metabolism
17.
Sci Rep ; 12(1): 15576, 2022 09 16.
Article in English | MEDLINE | ID: mdl-36114274

ABSTRACT

The gearbox has the advantage of being able to change the torque and rotational speed according to the gear ratio and has high power transmission efficiency by transmitting power through the contact of the gear pair. When evaluating the strength and fatigue life of a gearbox using a design load or an equivalent load, there is a possibility that the results will be very different from the actual ones. Therefore, in this study, the load duration distribution (LDD) constructed based on the actual workload was used to evaluate the strength and fatigue life of the gearbox reliably. As a result of evaluating the strength and fatigue life of the gearbox using LDD, it was confirmed that the existing gearbox did not satisfy the target lifespan in the operating environment. Therefore, the reasons for these results were analyzed, and design modification was performed based on the analyzed results. As a result of design modification, shaft deflection decreased by rearrangement of the bearings, from an overhung type to a straddle type, thereby improving the fatigue life of gears and bearings. Finally, the load distribution acting on the gear tooth surface was improved through micro-geometry modification of the gears.


Subject(s)
Fatigue , Zea mays , Torque
18.
Bioprocess Biosyst Eng ; 45(10): 1719-1729, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36121506

ABSTRACT

Polyhydroxybutyrate (PHB) is a bio-based, biodegradable and biocompatible plastic that has the potential to replace petroleum-based plastics. Lignocellulosic biomass is a promising feedstock for industrial fermentation to produce bioproducts such as polyhydroxybutyrate (PHB). However, the pretreatment processes of lignocellulosic biomass lead to the generation of toxic byproducts, such as furfural, 5-HMF, vanillin, and acetate, which affect microbial growth and productivity. In this study, to reduce furfural toxicity during PHB production from lignocellulosic hydrolysates, we genetically engineered Cupriavidus necator NCIMB 11599, by inserting the nicotine amide salvage pathway genes pncB and nadE to increase the NAD(P)H pool. We found that the expression of pncB was the most effective in improving tolerance to inhibitors, cell growth, PHB production and sugar consumption rate. In addition, the engineered strain harboring pncB showed higher PHB production using lignocellulosic hydrolysates than the wild-type strain. Therefore, the application of NAD salvage pathway genes improves the tolerance of Cupriavidus necator to lignocellulosic-derived inhibitors and should be used to optimize PHB production.


Subject(s)
Cupriavidus necator , Petroleum , Amides/metabolism , Cupriavidus necator/genetics , Cupriavidus necator/metabolism , Dietary Sugars/metabolism , Dietary Sugars/pharmacology , Furaldehyde/pharmacology , Growth Inhibitors/metabolism , Growth Inhibitors/pharmacology , Hydroxybutyrates/metabolism , Lignin , NAD/metabolism , NAD/pharmacology , Nicotine/metabolism , Nicotine/pharmacology , Nitrobenzenes , Petroleum/metabolism , Plastics
19.
J Womens Health (Larchmt) ; 31(11): 1587-1595, 2022 11.
Article in English | MEDLINE | ID: mdl-35666698

ABSTRACT

Background: Although high-risk pregnancies are common in clinical practice, there are limited data on the association of soluble suppression of tumorigenicity 2 (ST2) with pregnancy-related complications. The rates of maternal complications, including heart failure (HF) during the peripartum period, were evaluated according to the ST2 level. Materials and Methods: A single-center retrospective cohort study included and stratified 259 women with high-risk pregnancies in their early third trimester according to the ST2 levels. The primary endpoint was the occurrence of peripartum HF based on symptoms, N-terminal pro-brain natriuretic peptide, or echocardiography associated with fluid retention. The secondary endpoints consisted of pre-eclampsia, silent pleural effusion, and pericardial effusion during the peripartum period. We performed a logistic model for the association between ST2 and maternal complications. Results: Of the 259 patients (mean age: 36.4 years, mean gestational duration: 31.6 weeks), advanced age ≥35 years and twin gestation were the most prevalent risk factors. Patients with ST2 ≥ 35 ng/mL showed enlarged cardiac chambers. Peripartum HF occurred in 2 (1.6%) out of 121 patients with ST2 < 35 ng/mL and in 47 (34%) out of 138 patients with ST2 ≥ 35 ng/mL. Those with ST2 ≥ 35 ng/mL were more likely to have the secondary endpoints (40.6% vs. 5.8%, p < 0.001). After adjustment, ST2 ≥ 35 ng/mL was associated with a six-fold occurrence of peripartum HF and a four-fold increase in the secondary endpoints. Conclusions: In women with high-risk pregnancies, peripartum HF and pre-eclampsia were not uncommon, and ST2 ≥ 35 ng/mL in the third trimester was independently related to maternal complications.


Subject(s)
Heart Failure , Pre-Eclampsia , Pregnancy , Humans , Female , Adult , Interleukin-1 Receptor-Like 1 Protein , Pre-Eclampsia/epidemiology , Peripartum Period , Pregnancy Trimester, Third , Retrospective Studies , Biomarkers , Heart Failure/epidemiology , Heart Failure/diagnosis , Prognosis
20.
Nanomaterials (Basel) ; 12(7)2022 Apr 06.
Article in English | MEDLINE | ID: mdl-35407348

ABSTRACT

Nano-composite filler has received attention for the application to high temperature and low humidity polymer electrolyte membrane (PEM) in fuel cell systems. Heteropolyacids (HPAs) are one of the most attractive materials because of their conductive and thermally stable properties, but have practical limitations due to their high solubility. We investigated the stabilization of HPA on imidazole modified mesoporous silica as a nano-composite filler. The role of mesoporous silica as a support for imidazole and the distribution of chemically bonded HPA on the surface were both confirmed through physical and chemical analysis. The developed nano-composite was utilized to a PEM as a proton conducting filler, cast with commercial AquivionTM solution. Changing the HPA: imidazole ratio and HPA wt%, the composite membrane of Im10/PWA6/Si-MCM-41 (PWA 10 wt%) resulted in higher proton conductivity compared to the non-modified membrane at all operation conditions, especially at high temperature (140 °C) and low relative humidity (RH 10%), with values of 0.3530 and 0.0241 S/m, respectively. A single cell test at H2/Air also showed the effect of adding the nano-composite filler at a wide range of temperatures, which outperformed a single cell with a pristine membrane even at an extremely low humidity condition.

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