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1.
Small ; 20(7): e2306652, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37806762

RESUMO

Gallium-based liquid metal systems hold vast potential in materials science. However, maximizing their possibilities is hindered by gallium's native oxide and interfacial functionalization. In this study, small-molecule ligands are adopted as surfactants to modify the surface of eutectic gallium indium (EGaIn) nanoparticles and suppress oxidation. Different p-aniline derivatives are explored. Next, the reduction of chloroanric acid (HAuCl4 ) onto these p-aniline ligand modified EGaIn nanoparticles is investigated to produce gold-decorated EGaIn nanosystems. It is found that by altering the concentrations of HAuCl4 or the p-aniline ligand, the formation of gold nanoparticles (AuNPs) on EGaIn can be manipulated. The reduction of interfacial oxidation and presence of AuNPs enhances electrical conductivity, plasmonic performance, wettability, stability, and photothermal performance of all the p-aniline derivative modified EGaIn. Of these, EGaIn nanoparticles covered with the ligand of p-aminobenzoic acid offer the most evenly distributed AuNPs decoration and perfect elimination of gallium oxides, resulting in the augmented electrical conductivity, and highest wettability suitable for patterning, enhanced aqueous stability, and favorable photothermal properties. The proof-of-concept application in photothermal therapy of cancer cells demonstrates significantly enhanced photothermal conversion performance along with good biocompatibility. Due to such unique characteristics, the developed gold-decorated EGaIn nanodroplets are expected to offer significant potential in precise medicine.

2.
Small ; : e2402116, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38923774

RESUMO

Interference colors hold significant importance in optics and arts. Current methods for printing interference colors entail complex procedures and large-scale printing systems for the scarcity of inks that exhibit both sensitivity and tunability to external fields. The production of highly transparent inks capable of rendering transmissive colors has presented ongoing challenges. Here, a type of paramagnetic ink based on 2D materials that exhibit polychrome in one magnetic field is invented. By precisely manipulating the doping ratio of magnetic elements within titanate nanosheets, the magneto-optical sensitivity named Cotton-Mouton coefficient is engineerable from 728 to a record high value of 3272 m-1 T-2, with negligible influence on its intrinsic wide optical bandgap. Combined with the sensitive and controllable magneto-responsiveness of the ink, modulate and non-invasively print transmissive interference colors using small permanent magnets are precised. This work paves the way for preparing transmissive interference colors in an energy-saving and damage-free manner, which can expand its use in widespread areas.

3.
J Transl Med ; 22(1): 28, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184580

RESUMO

BACKGROUND: Electrical activity has a crucial impact on the development and survival of neurons. Numerous recent studies have shown that noninvasive electrical stimulation (NES) has neuroprotective action in various retinal disorders. OBJECTIVE: To systematically review the literature on in vivo studies and provide a comprehensive summary of the neuroprotective action and the mechanisms of NES on retinal disorders. METHODS: Based on the PRISMA guideline, a systematic review was conducted in PubMed, Web of Science, Embase, Scopus and Cochrane Library to collect all relevant in vivo studies on "the role of NES on retinal diseases" published up until September 2023. Possible biases were identified with the adopted SYRCLE's tool. RESULTS: Of the 791 initially gathered studies, 21 articles met inclusion/exclusion criteria for full-text review. The results revealed the neuroprotective effect of NES (involved whole-eye, transcorneal, transscleral, transpalpebral, transorbital electrical stimulation) on different retinal diseases, including retinitis pigmentosa, retinal degeneration, high-intraocular pressure injury, traumatic optic neuropathy, nonarteritic ischemic optic neuropathy. NES could effectively delay degeneration and apoptosis of retinal neurons, preserve retinal structure and visual function with high security, and its mechanism of action might be related to promoting the secretion of neurotrophins and growth factors, decreasing inflammation, inhibiting apoptosis. The quality scores of included studies ranged from 5 to 8 points (a total of 10 points), according to SYRCLE's risk of bias tool. CONCLUSION: This systematic review indicated that NES exerts neuroprotective effects on retinal disease models mainly through its neurotrophic, anti-inflammatory, and anti-apoptotic capabilities. To assess the efficacy of NES in a therapeutic setting, however, well-designed clinical trials are required in the future.


Assuntos
Estimulação Elétrica , Doenças Retinianas , Humanos , Projetos de Pesquisa , Retina , Degeneração Retiniana , Doenças Retinianas/terapia
4.
Chemistry ; : e202400276, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757422

RESUMO

A hydrophobic Ni-PTFE modified electrode has been prepared by constant current and cathodic electroplating with a nickel sheet as substrate in a PTFE suspension. Then the Ni-PTFE modified electrode was used for electroreduction from aromatic amide to diarylimide. The electrochemical characterizations such as cyclic voltammogram, EIS, polarization curves, and electrode stability have been carried out by electrochemical workstation. The structure of the electroreduction product diarylimide was characterized by 1HNMR, FT-IR, MS(Mass Spectrum), and EA(Elemental Analyzer). Based on the hydrophobicity of the electrode, an approach suggested that the phenyl ketone radical may be formed by electroreductive deamination at the cathode. With the construction of C-N bond by the radical coupling, the electrocatalytic reduction may be comprised of a one-electron process including an ECC (Electrochemical-Chemical-Chemical) process. The electroreduction of aromatic amide to diarylimide may be controlled by both charge migration and concentration polarization. Electrocatalytic reduction of aromatic amides on Ni-PTFE-modified electrodes is all well conversion ratio.

5.
Brain Topogr ; 37(1): 75-87, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38145437

RESUMO

The effects of short-term mindfulness are associated with the different patterns (autonomic, audio guided, or experienced and certified mindfulness instructor guided mindfulness). However, robust evidence for reported the impacts of different patterns of mindfulness on mental health and EEG biomarkers of undergraduates is currently lacking. Therefore, we aimed to test the hypotheses that mindfulness training for undergraduates would improve mental health, and increase alpha power over frontal region and theta power over midline region at the single electrode level. We also describe the distinction among frequency bands patterns in different sites of frontal and midline regions. 70 participants were enrolled and assigned to either 5-day mindfulness or a waiting list group. Subjective questionnaires measured mental health and other psychological indicators, and brain activity was recorded during various EEG tasks before and after the intervention. The 5-day mindfulness training improved trait mindfulness, especially observing (p = 0.001, d = 0.96) and nonreactivity (p = 0.03, d = 0.56), sleep quality (p = 0.001, d = 0.91), and social support (p = 0.001, d = 0.95) while not in affect. Meanwhile, the expected increase in the alpha power of frontal sites (p < 0.017, d > 0.84) at the single electrode level was confirmed by the current data rather than the theta. Interestingly, the alteration of low-beta power over the single electrode of the midline (p < 0.05, d > 0.71) was difference between groups. Short-term mindfulness improves practitioners' mental health, and the potentially electrophysiological biomarkers of mindfulness on neuron oscillations were alpha activity over frontal sites and low-beta activity over midline sites.


Assuntos
Eletroencefalografia , Atenção Plena , Humanos , Saúde Mental , Inquéritos e Questionários , Biomarcadores
6.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542476

RESUMO

Sugar transporters play important roles in plant growth and development, flowering and fruiting, as well as responses to adverse abiotic and biotic environmental conditions. Lilies (Lilium spp.) are some of the most representative ornamental bulbous flowers. Sugar metabolism is critical for bulb formation in lilies; therefore, clarifying the amount and expression pattern of sugar transporters is essential for further analyzing their roles in bulb formation. In this study, based on the transcriptome data of the Lilium Oriental hybrid 'Sorbonne' and Lilium × formolongi, a total of 69 and 41 sugar transporters were identified in 'Sorbonne' and Lilium × formolongi, respectively, by performing bioinformatics analysis. Through phylogenetic analysis, monosaccharide transporters (MSTs) can be divided into seven subfamilies, sucrose transporters (SUTs) can be divided into three subgroups, and sugars will eventually be exported transporters (SWEETs) can be divided into four clades. According to an analysis of conserved motifs, 20, 14, and 12 conserved motifs were predicted in MSTs, SUTs, and SWEETs, respectively. A conserved domain analysis showed that MSTs and SUTs contained a single domain, whereas most of the SWEETs harbored two MtN3/saliva domains, also known as a PQ-loop repeat. The LohINT1, which was predicted to have a smaller number of transmembrane structural domains, was cloned and analyzed for subcellular localization. It was found that the LohINT1 protein is mainly localized in the cell membrane. In addition, the expression analysis indicated that 22 LohMSTs, 1 LohSUTs, and 5 LohSWEETs were upregulated in 'Sorbonne' 1 day after scale detachment treatment, suggesting that they may regulate the initiation of the bulblet. A total of 10 LflMSTs, 1 LflSUTs, and 6 LflSWEETs were upregulated 4~6 months after sowing, which corresponds to the juvenile-to-adult transition phase of Lilium × formolongi, suggesting that they may also play a role in the accompanying bulb swelling process. Combined with quantitative real-time PCR (qRT-PCR) analysis, LohSTP8 and LohSTP12 were significantly overexpressed during the extremely early stage of bulblet initiation, and LflERD6.3 was significantly overexpressed during the growth of the underground bulblet, suggesting that they may be key sugar transporters in the formation of lily bulbs, which needs further functional verification.


Assuntos
Lilium , Lilium/metabolismo , Filogenia , Metabolismo dos Carboidratos , Transcriptoma , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Açúcares/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
J Cell Mol Med ; 27(12): 1682-1696, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37154878

RESUMO

Perturbations in autophagy, apoptosis and differentiation have greatly affected the progression and therapy of acute myeloid leukaemia (AML). The role of X-linked inhibitor of apoptosis (XIAP)-related autophagy remains unclear in AML therapeutics. Here, we found that XIAP was highly expressed and associated with poor overall survival in patients with AML. Furthermore, pharmacologic inhibition of XIAP using birinapant or XIAP knockdown via siRNA impaired the proliferation and clonogenic capacity by inducing autophagy and apoptosis in AML cells. Intriguingly, birinapant-induced cell death was aggravated in combination with ATG5 siRNA or an autophagy inhibitor spautin-1, suggesting that autophagy may be a pro-survival signalling. Spautin-1 further enhanced the ROS level and myeloid differentiation in THP-1 cells treated with birinapant. The mechanism analysis showed that XIAP interacted with MDM2 and p53, and XIAP inhibition notably downregulated p53, substantially increased the AMPKα1 phosphorylation and downregulated the mTOR phosphorylation. Combined treatment using birinapant and chloroquine significantly retarded AML progression in both a subcutaneous xenograft model injected with HEL cells and an orthotopic xenograft model injected intravenously with C1498 cells. Collectively, our data suggested that XIAP inhibition can induce autophagy, apoptosis and differentiation, and combined inhibition of XIAP and autophagy may be a promising therapeutic strategy for AML.


Assuntos
Leucemia Mieloide Aguda , RNA Interferente Pequeno , Proteína Supressora de Tumor p53 , Humanos , Apoptose , Autofagia , Diferenciação Celular , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , RNA Interferente Pequeno/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
8.
Inorg Chem ; 62(2): 1062-1068, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36594447

RESUMO

Polydopamine (PDA) is a good adhesion agent for lots of gels inspired by the mussel, whereas hybrid organic-inorganic perovskites (HOIPs) usually exhibit extraordinary optoelectronic performance. Herein, mussel-inspired chemistry has been integrated with two-dimensional HOIPs first, leading to the preparation of new crystal (HDA)2PbBr4 (1) (DA = dopamine). The organic cation dopamine can be introduced into PDA resulting in a thin film of (HPDA)2PbBr4 (PDA-1). The dissolved inorganic components of layered perovskite in DMF solution together with H2O2 addition can facilitate DA polymerization greatly. More importantly, PDA-1 can inherit an excellent semiconductor property of HOIPs and robust adhesion of the PDA hydrogel resulting in a self-adhesive photoelectric coating on various interfaces.


Assuntos
Adesivos , Dopamina , Dopamina/química , Cimentos de Resina , Polimerização , Peróxido de Hidrogênio
9.
Plant Dis ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990522

RESUMO

Bacterial spot of tomato (BST), predominantly caused by Xanthomonas perforans (Xp) in Florida, is one of the most devastating diseases in hot, humid environments. Bacterial resistance to copper-based bactericides and antibiotics makes disease management extremely challenging. This necessitates alternative solutions to manage the disease. In this study, we used two novel hybrid copper and magnesium nanomaterials noted as magnesium double-coated (Mg-Db) and magnesium-copper (Mg-Cu), to manage BST. In in vitro experiments, no viable cells were recovered following 4 h exposure to 500 µg/ml of both Mg-Db and Mg-Cu, while 100 and 200 µg/ml required 24 h of exposure for complete inhibition. In viability assay using live/dead cell straining method and epifluorescence microscopy, copper tolerant Xp cells were killed within 4 h by both Mg-Cu and Mg-Db nanomaterials at 500 µg/ml, but not by copper hydroxide (Kocide 3000). In the greenhouse, Mg-Db and Mg-Cu at 100-500 µg/ml significantly reduced BST severity compared to micron-sized commercial Cu bactericide Kocide 3000 and the growers' standard (copper hydroxide + mancozeb) (P < 0.05). In field studies, Mg-Db and Mg-Cu nanomaterials significantly reduced disease severity in two out for field trials. Mg-Db at 500 µg/ml reduced BST severity by 34% compared to the non-treated control without affecting yield in Fall, 2020. The use of hybrid nanomaterials at the highest concentrations (500 µg/ml) used in the field experiments can reduce copper use by 90% compared to the growers' standard. In addition, there was no phytotoxicity observed with the use of hybrid nanomaterials in the field. These results suggest the potential of novel magnesium-copper based hybrid nanomaterials to manage copper-tolerant bacterial pathogens.

10.
Angew Chem Int Ed Engl ; 62(48): e202313728, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37818673

RESUMO

Information security has gained increasing attention in the past decade, leading to the development of advanced materials for anti-counterfeiting, encryption and instantaneous information display. However, it remains challenging to achieve high information security with simple encryption procedures and low-energy stimuli. Herein, a series of strain/temperature-responsive liquid crystal elastomers (LCEs) are developed to achieve dual-modal, multi-level information encryption and real-time, rewritable transient information display. The as-prepared polydomain LCEs can change from an opaque state to a transparent state under strain or temperature stimuli, with the transition strains or temperatures highly dependent on the concentration of long-chain flexible spacers. Information encrypted by different LCE inks can be decrypted under specific strains or temperatures, leading to multi-level protection of information security. Furthermore, with the combination of the phase transition of polydomain LCEs and the photothermal effect of multi-walled carbon nanotubes (MWCNTs), we achieved a repeatable transient information display by using near-infrared (NIR) light as a pen for writing. This study provides new insight into the development of advanced encryption materials with versatility and high security for broad applications.

11.
Biol Reprod ; 107(4): 1026-1034, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-35774023

RESUMO

G protein-coupled estrogen receptor (GPER), a seven-transmembrane G protein-coupled receptor, mediates the rapid pre-genomic signaling actions of estrogen and derivatives thereof. The expression of GPER is extensive in mammal male reproductive system. However, the functional role of GPER in mouse sperm has not yet been well recognized. This study revealed that GPER was expressed at the acrosome and the mid-flagellum of the mouse sperm. The endogenous GPER ligand 17ß-estradiol and the selective GPER agonist G1 increased intracellular Ca2+ concentration ([Ca2+]i) in mouse sperm, which could be abolished by G15, an antagonist of GPER. In addition, the G1-stimulated Ca2+ response was attenuated by interference with the phospholipase C (PLC) signaling pathways or by blocking the cation channel of sperm (CatSper). Chlortetracycline staining assay showed that the activation of GPER increased the incidence of acrosome-reacted sperm. Conclusively, GPER was located at the acrosome and mid-flagellum of the mouse sperm. Activation of GPER triggered the elevation of [Ca2+]i through PLC-dependent Ca2+ mobilization and CatSper-mediated Ca2+ influx, which promoted the acrosome reaction of mouse sperm.


Assuntos
Reação Acrossômica , Clortetraciclina , Animais , Cálcio/metabolismo , Clortetraciclina/metabolismo , Estradiol/metabolismo , Estrogênios/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Ligantes , Masculino , Mamíferos/metabolismo , Camundongos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Fosfolipases Tipo C/metabolismo
12.
Mol Hum Reprod ; 28(2)2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35040999

RESUMO

The maturation of sperms is dependent on the coordinated interactions between sperm and the unique epididymal luminal milieu, which is characterized by high K+ content. This study investigated the involvement of transient receptor potential vanilloid 4 (TRPV4) in the K+ secretion of epididymal epithelium. The expression level and cellular localization of TRPV4 and Ca2+-activated K+ channels (KCa) were analyzed via RT-PCR, real-time quantitative PCR, western blot and immunofluorescence. The functional role of TRPV4 was investigated using short-circuit current (ISC) and intracellular Ca2+ imaging techniques. We found a predominant expression of TRPV4 in the corpus and cauda epididymal epithelium. Activation of TRPV4 with a selective agonist, GSK1016790A, stimulated a transient decrease in the ISC of the epididymal epithelium. The ISC response was abolished by either the TRPV4 antagonists, HC067047 and RN-1734, or the removal of basolateral K+. Simultaneously, the application of GSK1016790A triggered Ca2+ influx in epididymal epithelial cells. Our data also indicated that the big conductance KCa (BK), small conductance KCa (SK) and intermediate conductance KCa (IK) were all expressed in rat epididymis. Pharmacological studies revealed that BK, but not SK and IK, mediated TRPV4-elicited transepithelial K+ secretion. Finally, we demonstrated that TRPV4 and BK were localized in the epididymal epithelium, which showed an increased expression level from caput to cauda regions of rat epididymis. This study implicates that TRPV4 plays an important role in the formation of high K+ concentration in epididymal intraluminal fluid via promoting transepithelial K+ secretion mediated by BK.


Assuntos
Epididimo , Canais de Cátion TRPV , Animais , Epididimo/metabolismo , Células Epiteliais/metabolismo , Epitélio/metabolismo , Masculino , Ratos , Espermatozoides/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
13.
Microb Cell Fact ; 21(1): 110, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655274

RESUMO

BACKGROUND: The most abundant human milk oligosaccharide in breast milk, 2'-fucosyllactose (2'-FL), has been approved as an additive to infant formula due to its multifarious nutraceutical and pharmaceutical functions in promoting neonate health. However, the low efficiency of de novo synthesis limits the cost-efficient bioproduction of 2'-FL. RESULTS: This study achieved 2'-FL de novo synthesis in a generally recognized as safe (GRAS) strain Bacillus subtilis. First, a de novo biosynthetic pathway for 2'-FL was introduced by expressing the manB, manC, gmd, wcaG, and futC genes from Escherichia coli and Helicobacter pylori in B. subtilis, resulting in 2'-FL production of 1.12 g/L. Subsequently, a 2'-FL titer of 2.57 g/L was obtained by reducing the competitive lactose consumption, increasing the regeneration of the cofactor guanosine-5'-triphosphate (GTP), and enhancing the supply of the precursor mannose-6-phosphate (M6P). By replacing the native promoter of endogenous manA gene (encoding M6P isomerase) with a constitutive promoter P7, the 2'-FL titer in shake flask reached 18.27 g/L. The finally engineered strain BS21 could produce 88.3 g/L 2'-FL with a yield of 0.61 g/g lactose in a 3-L bioreactor, without the addition of antibiotics and chemical inducers. CONCLUSIONS: The efficient de novo synthesis of 2'-FL can be achieved by the engineered B. subtilis, paving the way for the large-scale bioproduction of 2'-FL titer in the future.


Assuntos
Bacillus subtilis , Lactose , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Fucosiltransferases/metabolismo , Humanos , Recém-Nascido , Lactose/metabolismo , Trissacarídeos
14.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365880

RESUMO

An implantable stacked planar inverted-F antenna (PIFA) for biotelemetric communication in the 402-405 MHz Medical Implant Communications Service (MICS) frequency band is designed and fabricated. With the proposed PIFA structure, a slot on each radiating patch was embedded, resulting in a size reduction of 0.013 λ and a compact size of 10 × 10 × 1.905 mm3. Both in vitro and in vivo experiments verified the simulation performance with characteristics of -10 dB bandwidth of 29 MHz, radiation efficiency of 0.9%, and a maximum far-field gain of -18.8 dB. We calculated the safety power delivered to the antenna using the specific absorption rate (SAR) limitation standard. Compared to other implantable antennas for biotelemetry, this antenna performs comparably and has a smaller size. This design would further develop implantable medical devices that communicate in the MICS band.


Assuntos
Comunicação , Próteses e Implantes , Desenho de Equipamento , Simulação por Computador
15.
J Am Chem Soc ; 143(32): 12886-12893, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34369770

RESUMO

Collective behavior widely exists in nature, ranging from the macroscopic cloud of swallows to the microscopic cloud of colloidal particles. The behavior of an individual inside the collective is distinctive from its behavior alone, as it follows its neighbors. The introduction of such collective behavior in two-dimensional (2D) materials may offer new degrees of freedom to achieve desired but unattained properties. Here, we report a highly sensitive magneto-optic effect and transmissive magneto-coloration via introduction of collective behavior into magnetic 2D material dispersions. The increase of ionic strength in the dispersion enhances the collective behavior of colloidal particles, giving rise to a magneto-optic Cotton-Mouton coefficient up to 2700 T-2 m-1 which is the highest value obtained so far, being 3 orders of magnitude larger than other known transparent media. We also reveal linear dependence of magneto-coloration on the concentration and hydration ratios of ions. Such linear dependence and the extremely large Cotton-Mouton coefficient cooperatively allow fabrication of giant magneto-birefringent devices for color-centered visual sensing.

16.
Environ Microbiol ; 22(4): 1547-1558, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31715659

RESUMO

Biofilms are architecturally complex communities of microbial cells held together by a self-produced extracellular matrix. Considerable research has focused on the environmental signals that trigger or inhibit biofilm formation by affecting cellular signalling pathways; however, response to soil cues in plant-associated Bacillus has remained largely unaddressed. Therefore, we aimed to investigate the effect of Zn(II) ions in biofilm formation of Bacillus amyloliquefaciens FZB42. We demonstrated that the biofilm formation of B. amyloliquefaciens FZB42 was abolished by Zn(II) at non-deleterious concentrations. Moreover, Zn(II) blocked matrix exopolysaccharide and TasA accumulations. Furthermore, the presence of Zn(II) suppressed expression of the response regulator Spo0F but not of sensor histidine kinases KinA-D. Suppression of phosphorelay by excess Zn interferes with sinI induction under biofilm-inducing conditions, leading to repression of transcription of operons epsA-O and tapA-sigW-tasA. Addition of Zn(II) decreased the intracellular Mn(II) level by competing for binding to the solute-binding protein MntA during Mn(II) uptake. These results suggest that the metal ion Zn(II) has a negative effect on biofilm formation in the plant growth promoting and biocontrol bacterium B. amyloliquefaciens FZB42.


Assuntos
Bacillus amyloliquefaciens/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Manganês/metabolismo , Zinco/farmacologia , Bacillus amyloliquefaciens/fisiologia , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Transporte Biológico/efeitos dos fármacos , Histidina Quinase/metabolismo , Óperon
17.
Appl Microbiol Biotechnol ; 104(21): 9109-9124, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32974742

RESUMO

As natural metabolites, organic acids have been widely applied in food, pharmaceutical, and bio-based materials industries. Particularly, the short-chain organic acids, including C2, C3, C4, C5, and C6 organic acids, are necessary intermediate metabolites in cells and are also alternatives to some commercial chemical products. As the necessary metabolites in cells, most major short-chain organic acids can be produced through microbial fermentation. Specifically, with the development of synthetic biology, metabolic engineering could endow cells with the ability to produce more short-chain organic acid products including propionic acid, pyruvate, lactic acid, 3-hydroxypropionic acid, malic acid, succinic acid, fumaric acid, butyric acid, itaconic acid, α-ketoglutaric acid, glutaric acid, citric acid, gluconic acid, muconic acid, adipic acid, xylonic acid, and so on. The recent advances in the biological production of short-chain organic acids, as well as the challenges and perspectives, are summarized in this review to promote the generation of microbial cell factories for the production of short-chain organic acids.Key points• Outlines the production strategy of short-chain organic acids• Provide guidance for efficient synthesis of short-chain organic acids• Impacts the necessary factor of acid resistance on the successful production of host cells.


Assuntos
Engenharia Metabólica , Ácido Succínico , Ácidos , Fermentação , Compostos Orgânicos
18.
Clin Exp Hypertens ; 41(5): 492-497, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30235005

RESUMO

Fas knockout (Fas-/-) mice are a model for systemic lupus erythematosus (SLE) -like autoimmune syndromes. We aimed to induce atherosclerosis (AS) in Fas-/- mice. Sixteen male Fas-/- mice were included in the study, sex-matched C57B6/L (B6) and apolipoprotein E-knockout (ApoE-/-) mice were negative and positive AS controls, respectively. A silica collar was placed around the right carotid artery of each mouse to induce AS development. All mice were fed a 24-week high-fat diet, and investigated for AS lesions. We also compared the levels of blood lipid and glucose, serum tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), anti-nuclear antibody (ANA) and anti-double-stranded deoxyribonucleic acid (anti-dsDNA) antibody in Fas-/- mice with those in B6 or ApoE-/- mice. All ApoE-/- and 6 Fas-/- but no B6 mice showed atherogenesis in right carotid artery. The carotid plaque contains more collagen and less lipid in Fas-/- than ApoE-/- mice. The levels of blood glucose, serum TNF-α, IL-6, ANA, and anti-dsDNA antibody were significantly higher in Fas-/- mice than those in B6 mice, the levels of serum TNF-α and blood glucose were significantly higher and the level of blood lipid was significantly lower in Fas-/- mice than those in ApoE-/- mice. Therefore, carotid AS can develop in Fas-/- mice. Fas-/- mice display higher levels of serum IL-6, TNF-α, ANA, and anti-dsDNA than B6 mice, higher levels of serum TNF-α and blood glucose and lower level of blood lipid than ApoE-/- mice, and less lipid and more collagen in AS plaque than ApoE-/- mice.


Assuntos
Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Lipídeos/sangue , Placa Aterosclerótica/metabolismo , Receptor fas/genética , Animais , Anticorpos Antinucleares/sangue , Glicemia/metabolismo , Colágeno/metabolismo , DNA/imunologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Interleucina-6/sangue , Lúpus Eritematoso Sistêmico/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica/diagnóstico por imagem , Fator de Necrose Tumoral alfa/sangue
19.
BMC Plant Biol ; 17(1): 133, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28768498

RESUMO

BACKGROUND: Microbial volatiles play an expedient role in the agricultural ecological system by enhancing plant growth and inducing systemic resistance against plant pathogens, without causing hazardous effects on the environment. To explore the effects of VOCs of Ralstonia solanacearum TBBS1 (Rs) on tobacco plant growth and on plant growth promoting efficiency of VOCs produced by Bacillus subtilis SYST2, experiments were conducted both in vitro and in planta. RESULTS: The VOCs produced by SYST2 significantly enhanced the plant growth and induced the systemic resistance (ISR) against wilt pathogen Rs in all experiments. The SYST2-VOCs significantly increased PPO and PAL activity and over-expressed the genes relating to expansin, wilt resistance, and plant defense while repressed the genes relating to ethylene production. More interestingly, VOCs produced by pathogen, Rs had no significant effect on plant growth; however, Rs-VOCs decreased the growth promoting potential of SYST2-VOCs when plants were exposed to VOCs produced by both SYST2 and Rs. The co-culture of SYST2 and Rs revealed that they inhibited the growth of each other; however, the inhibition of Rs by SYST2-VOCs appeared to be greater than that of SYST2 by Rs-VOCs. CONCLUSION: Our findings provide new insights regarding the interaction among SYST2-VOCs, Rs-VOCs and plant, resulting in growth promotion and induced systemic resistance against the bacterial wilt pathogen Rs. This is the first report of the effect of VOCs produced by pathogenic microorganism on plant growth and on plant growth-promoting and systemic resistance-inducing potential of PGPR strain SYST2.


Assuntos
Bacillus subtilis/metabolismo , Nicotiana/crescimento & desenvolvimento , Nicotiana/imunologia , Ralstonia solanacearum/fisiologia , Compostos Orgânicos Voláteis/metabolismo , Albuterol/metabolismo , Propilenoglicóis/metabolismo , Nicotiana/microbiologia
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