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1.
BMC Biotechnol ; 24(1): 15, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521922

RESUMO

BACKGROUND: Removal of heavy metals from water and soil is a pressing challenge in environmental engineering, and biosorption by microorganisms is considered as one of the most cost-effective methods. In this study, the metal-binding proteins MerR and ChrB derived from Cupriavidus metallidurans were separately expressed in Escherichia coli BL21 to construct adsorption strains. To improve the adsorption performance, surface display and codon optimization were carried out. RESULTS: In this study, we constructed 24 adsorption engineering strains for Hg2+ and Cr6+, utilizing different strategies. Among these engineering strains, the M'-002 and B-008 had the strongest heavy metal ion absorption ability. The M'-002 used the flexible linker and INPN to display the merRopt at the surface of the E. coli BL21, whose maximal adsorption capacity reached 658.40 µmol/g cell dry weight under concentrations of 300 µM Hg2+. And the B-008 overexpressed the chrB in the intracellular, its maximal capacity was 46.84 µmol/g cell dry weight under concentrations 500 µM Cr6+. While in the case of mixed ions solution (including Pb2+, Cd2+, Cr6+ and Hg2+), the total amount of ions adsorbed by M'-002 and B-008 showed an increase of up to 1.14- and 4.09-folds, compared to the capacities in the single ion solution. CONCLUSION: The construction and optimization of heavy metal adsorption strains were carried out in this work. A comparison of the adsorption behavior between single bacteria and mixed bacteria systems was investigated in both a single ion and a mixed ion environment. The Hg2+ absorption capacity is reached the highest reported to date with the engineered strain M'-002, which displayed the merRopt at the surface of chassis cell, indicating the strain's potential for its application in practical environments.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Adsorção , Proteínas de Transporte/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Íons/metabolismo , Mercúrio/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo
2.
Plant Biotechnol J ; 22(8): 2312-2326, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38548388

RESUMO

Carotenoids are indispensable to plants and critical components of the human diet. The carotenoid metabolic pathway is conserved across plant species, but our understanding of the genetic basis of carotenoid variation remains limited for the seeds of most cereal crops. To address this issue, we systematically performed linkage and association mapping for eight carotenoid traits using six recombinant inbred line (RIL) populations. Single linkage mapping (SLM) and joint linkage mapping (JLM) identified 77 unique additive QTLs and 104 pairs of epistatic QTLs. Among these QTLs, we identified 22 overlapping hotspots of additive and epistatic loci, highlighting the important contributions of some QTLs to carotenoid levels through additive or epistatic mechanisms. A genome-wide association study based on all RILs detected 244 candidate genes significantly associated with carotenoid traits, 23 of which were annotated as carotenoid pathway genes. Effect comparisons suggested that a small number of loci linked to pathway genes have substantial effects on carotenoid variation in our tested populations, but many loci not associated with pathway genes also make important contributions to carotenoid variation. We identified ZmPTOX as the causal gene for a QTL hotspot (Q10/JLM10/GWAS019); this gene encodes a putative plastid terminal oxidase that produces plastoquinone-9 used by two enzymes in the carotenoid pathway. Natural variants in the promoter and second exon of ZmPTOX were found to alter carotenoid levels. This comprehensive assessment of the genetic mechanisms underlying carotenoid variation establishes a foundation for rewiring carotenoid metabolism and accumulation for efficient carotenoid biofortification.


Assuntos
Carotenoides , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Zea mays , Carotenoides/metabolismo , Zea mays/genética , Zea mays/metabolismo , Locos de Características Quantitativas/genética , Sementes/genética , Sementes/metabolismo , Ligação Genética , Epistasia Genética
3.
IEEE Sens J ; 24(5): 6469-6481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39309301

RESUMO

In this paper, we propose mmPose-FK, a novel millimeter wave (mmWave) radar-based pose estimation method that employs a dynamic forward kinematics (FK) approach to address the challenges posed by low resolution, specularity, and noise artifacts commonly associated with mmWave radars. These issues often result in unstable joint poses that vibrate over time, reducing the effectiveness of traditional pose estimation techniques. To overcome these limitations, we integrate the FK mechanism into the deep learning model and develop an end-to-end solution driven by data. Our comprehensive experiments using various matrices and benchmarks highlight the superior performance of mmPose-FK, especially when compared to our previous research methods. The proposed method provides more accurate pose estimation and ensures increased stability and consistency, which underscores the continuous improvement of our methodology, showcasing superior capabilities over its antecedents. Moreover, the model can output joint rotations and human bone lengths, which could be further utilized for various applications such as gait parameter analysis and height estimation. This makes mmPose-FK a highly promising solution for a wide range of applications in the field of human pose estimation and beyond.

4.
IEEE Robot Autom Mag ; 31(3): 170-185, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39465183

RESUMO

Fall detection, particularly critical for high-risk demographics like the elderly, is a key public health concern where timely detection can greatly minimize harm. With the advancements in radio frequency technology, radar has emerged as a powerful tool for human detection and tracking. Traditional machine learning algorithms, such as Support Vector Machines (SVM) and k-Nearest Neighbors (kNN), have shown promising outcomes. However, deep learning approaches, notably Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN), have outperformed in learning intricate features and managing large, unstructured datasets. This survey offers an in-depth analysis of radar-based fall detection, with emphasis on Micro-Doppler, Range-Doppler, and Range-Doppler-Angles techniques. We discuss the intricacies and challenges in fall detection and emphasize the necessity for a clear definition of falls and appropriate detection criteria, informed by diverse influencing factors. We present an overview of radar signal processing principles and the underlying technology of radar-based fall detection, providing an accessible insight into machine learning and deep learning algorithms. After examining 74 research articles on radar-based fall detection published since 2000, we aim to bridge current research gaps and underscore the potential future research strategies, emphasizing the real-world applications possibility and the unexplored potential of deep learning in improving radar-based fall detection.

5.
Luminescence ; 38(6): 722-728, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37057382

RESUMO

As an effective ingredient of disinfectants, ClO- inevitably remains in water, which induces potential health hazards such as lung damage and kidney disease. In this study, we synthesized stimulus-responsive dual-ligand luminol-Tb-GMP coordination polymer nanoparticles (luminol-Tb-GMP CPNPs) as highly selective fluorescent probes for the real-time and visual detection of ClO- . CPNPs consist of Tb3+ , a nuclear metal, that coordinates with GMP and luminol, an auxiliary ligand. GMP can be oxidized by ClO- and damage its structure, resulting in fluorescence quenching of CPNPs. The two-ligand CPNPs sensor has a rapid fluorescent response, significant fluorescent color change, and high sensitivity, with a linear range of 2-18 µM and a detection limit of 0.14 µM. It has been successfully used to detect ClO- in tap water, fountain water, and drinking water. Simultaneously, the portable filter paper strip was prepared to expand the range of applications outside the laboratory, which will provide a promising application for the real-time and semiquantitative analysis of ClO- .


Assuntos
Água Potável , Corantes Fluorescentes , Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Espectrometria de Fluorescência/métodos , Ligantes , Luminol/análise , Água Potável/análise
6.
Molecules ; 28(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36838778

RESUMO

Kinkéliba (Combretum micranthum, Seh-Haw in Wolof) is a popular bush tea in West African countries. Although the kinkéliba plant's leaves have been widely consumed for its nutritional and medicinal properties, its benefits on skin health potential have been practically untouched. In human epidermal primary keratinocytes, vitexin and isovitexin-rich kinkéliba extract treatment significantly (p < 0.001) enhanced up to 39.6% of the cell survival rate decreased by UV radiation irritation. The treatment of kinkéliba leaf extracts also reduced the production of UV-induced pro-inflammatory cytokines IL-6 and IL-8 by 57.6% and 42.5%, respectively (p < 0.001), which cause skin redness and skin barrier dysfunction, as well as wrinkles and collagen degradation. The anti-inflammation efficacy of kinkéliba leaf extracts might involve significant inhibition on the levels of cellular reactive oxygen species (ROS) (-70.8%, p < 0.001) and nitrotyrosine (-56.9%, p < 0.05). Further topical applications of kinkéliba leaf extract gel were found to reduce sodium lauryl sulfate (SLS)-induced skin inflammation: at D7, the skin trans-epidermal water loss (TEWL) and skin redness (a* value) were both reduced by 59.81% (p < 0.001) and 22.4% (p < 0.001), compared with D0. In vitro and in vivo data support a new topical application of the kinkéliba leaf as an effective active ingredient for the treatment of skin inflammation, as well as subsequent barrier dysfunction and inflammaging.


Assuntos
Combretum , Dermatite , Humanos , Extratos Vegetais/farmacologia , Pele , Queratinócitos
7.
J Exp Bot ; 73(14): 4968-4980, 2022 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-35511088

RESUMO

The accumulation of reducing sugars in cold-stored tubers, known as cold-induced sweetening (CIS), negatively affects potato processing quality. The starch to sugar interconversion pathways that are altered in cold-stored CIS tubers have been elucidated, but the mechanism that regulates them remains largely unknown. This study identified a CBF/DREB transcription factor (StTINY3) that enhances CIS resistance by both activating starch biosynthesis and repressing the hydrolysis of sucrose to reducing sugars in detached cold-stored tubers. Silencing StTINY3 in a CIS-resistant genotype decreased CIS resistance, while overexpressing StTINY3 in a CIS-sensitive genotype increased CIS resistance, and altering StTINY3 expression was associated with expression changes in starch resynthesis-related genes. We showed first that overexpressing StTINY3 inhibited sucrose hydrolysis by enhancing expression of the invertase inhibitor gene StInvInh2, and second that StTINY3 promoted starch resynthesis by up-regulating a large subunit of the ADP-glucose pyrophosphorylase gene StAGPaseL3, and the glucose-6-phosphate transporter gene StG6PT2. Using electrophoretic mobility shift assays, we revealed that StTINY3 is a nuclear-localized transcriptional activator that directly binds to the dehydration-responsive element/CRT cis-element in the promoters of StInvInh2 and StAGPaseL3. Taken together, these findings established that StTINY3 influences CIS resistance in cold-stored tubers by coordinately modulating the starch to sugar interconversion pathways and is a good target for improving potato processing quality.


Assuntos
Solanum tuberosum , Carboidratos , Temperatura Baixa , Hidrólise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tubérculos/metabolismo , Solanum tuberosum/metabolismo , Amido/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Cell Biol Int ; 46(3): 475-487, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34939719

RESUMO

Mutations of PSEN1 have been reported in dilated cardiomyopathy pedigrees. Understanding the effects and mechanisms of PSEN1 in cardiomyocytes might have important implications for treatment of heart diseases. Here, we showed that PSEN1 was downregulated in ischemia-induced failing hearts. Functionally, cardiovascular specific PSEN1 deletion led to spontaneous death of the mice due to cardiomyopathy. At the age of 11 months, the ratio of the heart weight/body weight was slightly lower in the Sm22a-PSEN1-KO mice compared with that of the WT mice. Echocardiography showed that the percentage of ejection fraction and fractional shortening was significantly reduced in the Sm22a-PSEN1-KO group compared with the percent of these measures in the WT group, indicating that PSEN1-KO resulted in heart failure. The abnormally regulated genes resulted from PSEN1-KO were detected to be enriched in muscle development and dilated cardiomyopathy. Among them, several genes encode Ca2+ ion channels, promoting us to investigate the effects of PSEN1 KO on regulation of Ca2+ in isolated adult cardiomyocytes. Consistently, in isolated adult cardiomyocytes, PSEN1-KO increased the concentration of cytosolic Ca2+ and reduced Ca2+ concentration inside the sarcoplasmic reticulum (SR) lumen at the resting stage. Additionally, SR Ca2+ was decreased in the failing hearts of WT mice, but with the lowest levels observed in the failing hearts of PSEN1 knockout mice. These results indicate that the process of Ca2+ release from SR into cytoplasm was affected by PSEN1 KO. Therefore, the abnormalities in Ca2+ homeostasis resulted from downregulation of PSEN1 in failing hearts might contribute to aging-related cardiomyopathy, which might had important implications for the treatment of aging-related heart diseases.


Assuntos
Cálcio , Cardiomiopatia Dilatada , Animais , Cardiomiopatia Dilatada/genética , Homeostase , Camundongos , Camundongos Knockout , Miócitos Cardíacos/fisiologia , Retículo Sarcoplasmático
9.
Plant Biotechnol J ; 19(11): 2192-2205, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34077617

RESUMO

Starch is the most abundant storage carbohydrate in maize kernels and provides calories for humans and other animals as well as raw materials for various industrial applications. Decoding the genetic basis of natural variation in kernel starch content is needed to manipulate starch quantity and quality via molecular breeding to meet future needs. Here, we identified 50 unique single quantitative trait loci (QTLs) for starch content with 18 novel QTLs via single linkage mapping, joint linkage mapping and a genome-wide association study in a multi-parent population containing six recombinant inbred line populations. Only five QTLs explained over 10% of phenotypic variation in single populations. In addition to a few large-effect and many small-effect additive QTLs, limited pairs of epistatic QTLs also contributed to the genetic basis of the variation in kernel starch content. A regional association study identified five non-starch-pathway genes that were the causal candidate genes underlying the identified QTLs for starch content. The pathway-driven analysis identified ZmTPS9, which encodes a trehalose-6-phosphate synthase in the trehalose pathway, as the causal gene for the QTL qSTA4-2, which was detected by all three statistical analyses. Knockout of ZmTPS9 increased kernel starch content and, in turn, kernel weight in maize, suggesting potential applications for ZmTPS9 in maize starch and yield improvement. These findings extend our knowledge about the genetic basis of starch content in maize kernels and provide valuable information for maize genetic improvement of starch quantity and quality.


Assuntos
Amido , Zea mays , Mapeamento Cromossômico , Ligação Genética , Estudo de Associação Genômica Ampla , Fenótipo , Locos de Características Quantitativas/genética , Zea mays/genética
10.
Plant Physiol ; 179(4): 1723-1738, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718347

RESUMO

Plastid isoprenoids, a diverse group of compounds that includes carotenoids, chlorophylls, tocopherols, and multiple hormones, are essential for plant growth and development. Here, we identified and characterized SEED CAROTENOID DEFICIENT (SCD), which encodes an enzyme that functions in the biosynthesis of plastid isoprenoids in maize (Zea mays). SCD converts 2C-methyl-d-erytrithol 2,4-cyclodiphosphate to 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate in the penultimate step of the methylerythritol phosphate (MEP) pathway. In scd mutants, plant growth and development are impaired and the levels of MEP-derived isoprenoids, such as carotenoids, chlorophylls, and tocopherols, as well as abscisic and gibberellic acids, are reduced in leaves and seeds. This scd metabolic alteration varies among plant tissues and under different light conditions. RNA-sequencing of the scd mutant and wild type identified a limited number of differentially expressed genes in the MEP pathway, although isoprenoid levels were significantly reduced in scd seeds and dark-grown leaves. Furthermore, SCD-overexpressing transgenic lines showed little or no differences in isoprenoid levels, indicating that SCD may be subject to posttranslational regulation or not represent a rate-limiting step in the MEP pathway. These results enhance our understanding of the transcriptomic and metabolic regulatory roles of enzymes in the MEP pathway and of their effects on downstream isoprenoid pathways in various plant tissues and under different light conditions.


Assuntos
Proteínas de Plantas/fisiologia , Zea mays/metabolismo , Carotenoides/metabolismo , Cloroplastos/genética , Cloroplastos/fisiologia , Mapeamento Cromossômico , Clonagem Molecular , Eritritol/análogos & derivados , Eritritol/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Fosfatos Açúcares/genética , Fosfatos Açúcares/metabolismo , Terpenos/metabolismo , Zea mays/genética , Zea mays/crescimento & desenvolvimento
11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 40(6): 445-7, 2016 Nov.
Artigo em Zh | MEDLINE | ID: mdl-29792609

RESUMO

Objective: Analyzing the status of medical device adverse events, the function of the clinical medical engineers in medical device adverse event monitoring was investigated. Methods: Through introducing the functions of the various departments in the medical device adverse event monitoring, the technical requirements and management responsibilities of clinical medical engineer and medical staff were defined. Results: Enhancing the function of clinical medical engineers in medical device adverse event monitoring,which is an effective measure to prevent medical device adverse events. Conclusion: Play the functions of clinical engineers in the medical device adverse event monitoring, which is significant to improve the using quality of medical devices and to ensure patient safety.


Assuntos
Segurança de Equipamentos , Equipamentos e Provisões , Humanos
12.
BMC Plant Biol ; 15: 288, 2015 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-26654531

RESUMO

BACKGROUND: Starch from maize kernels has diverse applications in human and animal diets and in industry and manufacturing. To meet the demands of these applications, starch quantity and quality need improvement, which requires a clear understanding of the functional mechanisms involved in starch biosynthesis and accumulation. In this study, a recombinant inbred line (RIL) population was developed from a cross between inbred lines CI7 and K22. The RIL population, along with both parents, was grown in three environments, and then genotyped using the MaizeSNP50 BeadChip and phenotyped to dissect the genetic architecture of starch content in maize kernels. RESULTS: Based on the genetic linkage map constructed using 2,386 bins as markers, six quantitative trait loci (QTLs) for starch content in maize kernels were detected in the CI7/K22 RIL population. Each QTL accounted for 4.7% (qSTA9-1) to 10.6% (qSTA4-1) of the starch variation. The QTL interval was further reduced using the bin-map method, with the physical distance of a single bin at the QTL peak ranging from 81.7 kb to 2.2 Mb. Based on the functional annotations and prior knowledge of the genes in the top bin, seven genes were considered as potential candidate genes for the identified QTLs. Three of the genes encode enzymes in non-starch metabolism but may indirectly affect starch biosynthesis, and four genes may act as regulators of starch biosynthesis. CONCLUSIONS: A few large-effect QTLs, together with a certain number of minor-effect QTLs, mainly contribute to the genetic architecture of kernel starch content in our maize biparental linkage population. All of the identified QTLs, especially the large-effect QTL, qSTA4-1, with a small QTL interval, will be useful for improving the maize kernel starch content through molecular breeding.


Assuntos
Polimorfismo de Nucleotídeo Único , Amido/metabolismo , Zea mays/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Ligação Genética , Endogamia , Fenótipo , Locos de Características Quantitativas , Sementes/química , Sementes/genética , Sementes/metabolismo , Amido/análise , Zea mays/química , Zea mays/metabolismo
13.
Chem Res Toxicol ; 28(3): 541-8, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25588103

RESUMO

Ultraviolet A not only plays a major part in photoaging and skin tanning but also induces genetic damage and mutation in the epidermal basal layer of human skin. The photoprotective effect of oxyresveratrol and kuwanon O, two phenolic compounds from the root extract of Morus australis, in human primary epidermal keratinocytes was investigated in this study. Both of them were nontoxic to cells at a concentration less than 10 and 0.5 µM, respectively. After pretreatment at the concentrations of 5 and 10 µM, oxyresveratrol increased cell viability, exhibited significant suppressions on UVA- or H2O2-induced cellular ROS. UVA-enhanced nitrotyrosine was also reduced by post-treatment with oxyresveratrol at theses concentrations. Kuwanon O presented similar inhibitions on cellular ROS and nitrotyrosine with lower concentrations (0.25 and 0.5 µM), but there is no significant protection on cell survival after UVA irradiation. Their photoprotective effects also involved the enhanced repair of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclobutane pyrimidine dimers (CPDs) as mediated by the augment of p53 expression after UVA radiation.


Assuntos
Dano ao DNA/efeitos dos fármacos , Flavanonas/farmacologia , Queratinócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Resorcinóis/farmacologia , Estilbenos/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Humanos , Peróxido de Hidrogênio , Queratinócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo , Raios Ultravioleta
14.
Synth Syst Biotechnol ; 8(2): 292-299, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37090062

RESUMO

In this study, we designed a Cd2+ whole-cell biosensor with both positive and negative feedback cascade amplifiers in Pseudomonas putida KT2440 (LTCM) based on our previous design with only a negative feedback amplifier (TCM). The results showed that the newly developed biosensor LTCM was greatly improved compared to TCM. Firstly, the linear response range of LTCM was expanded while the maximum linear response range was raised from 0.05 to 0.1 µM. Meanwhile, adding a positive feedback amplifier further increased the fluorescence output signal of LTCM 1.11-2.64 times under the same culture conditions. Moreover, the response time of LTCM for detection of practical samples was reduced from 6 to 4 h. At the same time, LTCM still retained very high sensitivity and specificity, while its lowest detection limit was 0.1 nM Cd2+ and the specificity was 23.29 (compared to 0.1 nM and 17.55 in TCM, respectively). In summary, the positive and negative feedback cascade amplifiers effectively improved the performance of the biosensor LTCM, resulting in a greater linear response range, higher output signal intensity, and shorter response time than TCM while retaining comparable sensitivity and specificity, indicating better potential for practical applications.

15.
Front Pharmacol ; 13: 758501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211009

RESUMO

Diabetes mellitus is a fast-growing disease with a major influence on people's quality of life. Oral hypoglycemic drugs and insulin are currently the main effective drugs in the treatment of diabetes, but chronic consumption of these drugs has certain side effects. Polysaccharides, saponins, flavonoids, and phenolics are the primary secondary metabolites isolated from the rhizomes of Polygonatum sibiricum Redouté [Asparagaceae], Polygonatum kingianum Collett & Hemsl [Asparagaceae], or Polygonatum cyrtonema Hua [Asparagaceae], which have attracted much more attention owing to their unique therapeutic role in the treatment and prevention of diabetes. However, the research on the mechanism of these three Polygonatum spp. in diabetes has not been reviewed. This review provides a summary of the research progress of three Polygonatum spp. on diabetes and its complications, reveals the potential antidiabetic mechanism of three Polygonatum spp., and discusses the effect of different processed products of three Polygonatum spp. in treating diabetes, for the sake of a thorough understanding of its effects on the prevention and treatment of diabetes and diabetes complications.

16.
Front Plant Sci ; 13: 1015815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262645

RESUMO

Cell wall invertase (CWI) is as an essential coordinator in carbohydrate partitioning and sink strength determination, thereby playing key roles in plant development. Emerging evidence revealed that the subtle regulation of CWI activity considerably depends on the post-translational mechanism by their inhibitors (INHs). In our previous research, two putative INHs (StInvInh1 and StInvInh3) were expected as targets of CWI in potato (Solanum tubersum), a model species of tuberous plants. Here, transcript analysis revealed that StInvInh1 showed an overall higher expression than StInhInh3 in all tested organs. Then, StInvInh1 was further selected to study. In accordance with this, the activity of StInvInh1 promoter increased with the development of leaves in plantlets but decreased with the development of microtubers in vitro and mainly appeared in vascular bundle. The recombinant protein StInvInh1 displayed inhibitory activities on the extracted CWI in vitro and StInvInh1 interacted with a CWI StcwINV2 in vivo by bimolecular fluorescence complementation. Furthermore, silencing StInvInh1 in potato dramatically increased the CWI activity without changing activities of vacuolar and cytoplasmic invertase, indicating that StInvInh1 functions as a typical INH of CWI. Releasing CWI activity in StInvInh1 RNA interference transgenic potato led to improvements in potato microtuber size in coordination with higher accumulations of dry matter in vitro. Taken together, these findings demonstrate that StInvInh1 encodes an INH of CWI and regulates the microtuber development process through fine-tuning apoplastic sucrose metabolism, which may provide new insights into tuber development.

17.
Front Bioeng Biotechnol ; 9: 799781, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926437

RESUMO

Although many whole-cell biosensors (WCBs) for the detection of Cd2+ have been developed over the years, most lack sensitivity and specificity. In this paper, we developed a Cd2+ WCB with a negative feedback amplifier in P. putida KT2440. Based on the slope of the linear detection curve as a measure of sensitivity, WCB with negative feedback amplifier greatly increased the output signal of the reporter mCherry, resulting in 33% greater sensitivity than in an equivalent WCB without the negative feedback circuit. Moreover, WCB with negative feedback amplifier exhibited increased Cd2+ tolerance and a lower detection limit of 0.1 nM, a remarkable 400-fold improvement compared to the WCB without the negative feedback circuit, which is significantly below the World Health Organization standard of 27 nM (0.003 mg/L) for cadmium in drinking water. Due to the superior amplification of the output signal, WCB with negative feedback amplifier can provide a detectable signal in a much shorter time, and a fast response is highly preferable for real field applications. In addition, the WCB with negative feedback amplifier showed an unusually high specificity for Cd2+ compared to other metal ions, giving signals with other metals that were between 17.6 and 41.4 times weaker than with Cd2+. In summary, the negative feedback amplifier WCB designed in this work meets the requirements of Cd2+ detection with very high sensitivity and specificity, which also demonstrates that genetic negative feedback amplifiers are excellent tools for improving the performance of WCBs.

18.
Front Pharmacol ; 12: 722502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456732

RESUMO

Background: Thalidomide has been reported as a promising treatment for reducing transfusion volume in adults with ß-thalassemia. However, the evidence about the safety and efficacy of thalidomide on children with transfusion dependent ß-thalassemia (TDT) is scarce. Methods: Seventy-seven children with TDT treated with thalidomide at least for 6 months were included and retrospectively analyzed. Oral dose was started at 2.5 mg·kg-1·d-1. Blood volume for maintenance of hemoglobin above 90 g·L-1 compared with pre-treatment volume is the evaluation index for response. Results: After the sixth month treatment, 51/77 (66.2%) maintained Hb over 90 g·L-1 without transfusion. Adverse events were reported in 48 (63.2%) patients. Age, sex, genotype category, dosage, and transfusion interval before thalidomide treatment were not correlated to treatment response. The AUC was 0.806 for the HbF at the third month of treatment in predicting probability of major responders at the sixth month treatment. Based on Youden's index algorithm in the ROC curve, 47.298 g·L-1 was the optimal cut-off value of the HbF at the third month of treatment in predicting major responders at the sixth month treatment, with sensitivity of 67.5% and specificity of 93.3%. Conclusions: The dose of thalidomide between 2.5 mg·kg-1·d-1 and 3.6 mg·kg-1·d-1 is effective in TDT children. Severe side effects are uncommon. HbF concentration of 47.298 g·L-1 at the third month is recommended as the predictor for further major responders.

19.
Food Chem ; 341(Pt 1): 128163, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33035853

RESUMO

Lactic acid bacteria fermentation is a safe and green technology that can modify the function of food ingredients (including proteins). In this article, egg yolks were subjected to fermentation with commercial lactic acid bacteria for 0, 3, 6 and 9 h, respectively. After fermentation treatment, the microbial composition has changed obviously (Streptococcus thermophilus increased significantly). The free sulfhydryl group (SH) contents and surface hydrophobicity of egg yolk proteins were significantly reduced. The rheological results indicated that the treated egg yolks possessed a decreased apparent viscosity. Correspondingly, the emulsifying activity of egg yolk was enhanced from 9.07 to 19.55, 23.40 and 24.61 m2/g for 3, 6 and 9 h of fermentation, respectively. And the emulsifying stability reached the maximum after 3 h of fermentation. This study investigated the relationship between structure and properties of yolk proteins, and showed that lactic acid fermentation endued egg yolk with better emulsifying properties.


Assuntos
Proteínas do Ovo/química , Gema de Ovo/química , Gema de Ovo/microbiologia , Lactobacillales/metabolismo , Animais , Proteínas do Ovo/análise , Proteínas do Ovo/metabolismo , Emulsões/química , Fermentação , Microbiologia de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Reologia , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo , Compostos de Sulfidrila/química , Viscosidade
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1710-1717, 2020 Oct.
Artigo em Zh | MEDLINE | ID: mdl-33067979

RESUMO

AbstractObjective: To investigate the effect of ALAS2 downregulation on the expression of BNIP3L and erythroid differentiation in K562 cells. METHODS: The expression of ALAS2 was down-regulated by transfection of lentivirus, then quantitative real-time PCR was performed to detect the transfection efficiency. Flow cytometry analysis was applied to evaluate apoptosis of cells, erythroid differentiation, mitochondrial membrane potential and reactive oxygen species (ROS) level. Western blot was used to detect the BNIP3L expression, Co-immunoprecipitation was performed to analyze the relationship between ALAS2 and BNIP3L. RESULTS: Compared with sh-NC group, knockdown of ALAS2 induced downregulation of BNIP3L mRNA and protein expression(P<0.01) and erythroid related transcription factors GATA1, Nrf2 expression, as well as reduction of ROS level(P<0.05). Mitochondrial membrane potential of control (sh-NC) group was lower than that of shALAS2 group(P<0.05), but there was no significant change of cell apoptotic rate in two groups. CD71highCD235ahigh + CD71lowCD235ahigh cells of sh-NC and shALAS2 groups were 53.5%, 92.9% at 96 h after hemin induction, respectively. No direct action between ALAS2 and BNIP3L was observed. CONCLUSION: The intracellular heme level can affect the expression of BNIP3L which may be related with the regulation of ROS and transcription factors GATA1 and Nrf2. Higher BNIP3L facilitates cell differentiation but lower BNIP3L is favorable for cells survival.


Assuntos
Proteínas de Transporte , Mitofagia , 5-Aminolevulinato Sintetase/metabolismo , Apoptose , Diferenciação Celular , Humanos , Células K562 , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Supressoras de Tumor
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