RESUMO
Ypt GTPases are the largest subfamily of small GTPases involved in membrane transport. Here, a PeYpt7 gene deletion mutant of P. expansum was constructed. The ΔPeYpt7 mutant showed reduced colony growth with abnormal mycelial growth, reduced conidiation, and insufficient spore development. The mutation rendered the pathogen susceptible to osmotic stress and cell wall stressors. In addition, the absence of PeYpt7 reduced patulin production in P. expansum and significantly limited gene expression (PatG, PatH, PatI, PatD, PatF, and PatL). In addition, the mutant showed attenuated virulence in infected fruit and reduced expression of pathogenic factors was (PMG, PG, PL, and GH1). Thus, PeYpt7 modulates the growth, morphology, patulin accumulation, and pathogenicity of P. expansum by limiting the expression of related genes.
Assuntos
Malus , Proteínas Monoméricas de Ligação ao GTP , Patulina , Penicillium , Virulência/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Frutas/metabolismoRESUMO
Phospholipase D plays a critical regulatory role in the pathogenicity of filamentous fungi. However, the molecular mechanism of PLD regulating the pathogenicity of filamentous fungi has not been reported. In this research, the previously constructed TrPLD1 and TrPLD2 (TrPLDs) mutants were used as test strains. Firstly, the function of TrPLDs in Trichothecium roseum was studied. Then, the effects of TrPLDs on the pathogenicity of T. roseum and the quality of the inoculated apples were verified. The results suggested that the deletion of TrPLD1 delayed the spore germination of ΔTrPLD1 and inhibited germ tube elongation by down-regulating the expressions of TrbrlA, TrabaA and TrwetA. By down-regulating the extracellular enzyme-coding gene expressions, ΔTrPLD1 inhibited the degradation of apple fruit cell wall and the change of fatty acid content during infection, reduced the cell membrane permeability and malondialdehyde (MDA) content of apple fruit, thereby maintaining the integrity of fruit cell membrane, and reduced the pathogenicity of ΔTrPLD1 to apple and kept the quality of apple. However, ΔTrPLD2 did not have a significant effect on the infection process of apple fruit by the pathogen.
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Hypocreales , Malus , Malus/microbiologia , Frutas/microbiologia , Virulência/genéticaRESUMO
Acyl radicals are significant synthetic active species in organic synthesis. However, their generation via green and compatible methods remains challenging. Herein, we report an unprecedented visible-light-mediated approach for generating aryl acyl radicals from readily available triazine esters. This protocol with mild and redox-neutral conditions affords a diverse array of oxindoles attached to alcohol groups in a single operation. The recycling of leaving groups and a range of visible-light-mediated reactions using triazine ester as an acyl radical precursor demonstrate the synthetic potential of this methodology.
RESUMO
pH is one of the important environmental factors that affect the growth, development and pathogenicity of postharvest pathogen. The transcription factor PacC dominates the pH signal pathway. PacC in Trichothecium roseum showed three typical conserved zinc finger domains and closest homology to Fusarium graminearum. T. roseum increased the environmental pH both in vitro and in vivo. Expression patterns of TrpacC under different pH showed that at increasing pH from 3 to 5, the wild-type (WT) strain induced the expression of TrPacC in parallel to increased fungal growth; however, TrPacC expression decline at higer pH than 5, while fungal growth continued to increase. Development of a ΔTrPacC mutant down-regulated the expression of TrbrlA, TrabaA and TrwetA, reduced sporulation and delayed spore germination, resulting in smaller spores and sparse hyphae. ΔTrPacC mutant was sensitive to ionic stress, oxidative stress and cell wall integrity stress compared to the WT strain, especially the ionic stress. In addition, ∆TrPacC mutant showed reduced pathogenicity to muskmelon and tomato fruits. Taken together, T. roseum is an alkalinizing fungus, and the acidic environment could induce TrPacC expression. TrPacC positively regulates fungal growth and development as well as pathogenicity showing effect on fungal response to different stresses.
Assuntos
Regulação Fúngica da Expressão Gênica , Fatores de Transcrição , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Hypocreales , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Virulência/genéticaRESUMO
OBJECTIVE: There are limited data from retrospective studies on whether therapeutic outcomes after regular pancreatectomy are superior to those after enucleation in patients with small, peripheral and well-differentiated non-functional pancreatic neuroendocrine tumors. This study aimed to compare the short- and long-term outcomes of regular pancreatectomy and enucleation in patients with non-functional pancreatic neuroendocrine tumors. METHODS: Between January 2007 and July 2020, 227 patients with non-functional pancreatic neuroendocrine tumors who underwent either enucleation (n = 89) or regular pancreatectomy (n = 138) were included. Perioperative complications, disease-free survival, and overall survival probabilities were compared. Propensity score matching was performed to balance the baseline differences between the two groups. RESULTS: The median follow-up period was 60.76 months in the enucleation group and 43.29 months in the regular pancreatectomy group. In total, 34 paired patients were identified after propensity score matching. The average operative duration in the enucleation group was significantly shorter than that in the regular pancreatectomy group (147.94 ± 42.39 min versus 217.94 ± 74.60 min, P < 0.001), and the estimated blood loss was also significantly lesser (P < 0.001). The matched patients who underwent enucleation displayed a similar overall incidence of postoperative complications (P = 0.765), and a comparable length of hospital stay (11.12 ± 3.90 days versus 9.94 ± 2.62 days, P = 0.084) compared with those who underwent regular pancreatectomy. There were no statistically significant differences between the two groups in disease-free survival and overall survival after propensity score matching. CONCLUSION: Enucleation in patients with non-functional pancreatic neuroendocrine tumors was associated with shorter operative time, lesser intraoperative bleeding, similar overall morbidity of postoperative complications, and comparable 5-year disease-free survival and overall survival when compared with regular pancreatectomy.
Assuntos
Tumores Neuroendócrinos/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Pontuação de Propensão , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Duração da Cirurgia , Pancreatectomia/efeitos adversos , Pancreatectomia/mortalidade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
A Gram-stain-negative, rod-shaped bacterium, strain H23T, was isolated from farmland soil sampled in Enshi City, Hubei Province, PR China. The isolate grew optimally at 28-32 °C, pH 8.0 and with 0.5â% (w/v) NaCl. Based on the results of 16S rRNA gene sequence and phylogenetic analyses, strain H23T belonged to the genus Luteimonas with the highest degree of 16S rRNA gene sequence similarity to Luteimonas cucumeris Y4T (97.41â%). The DNA G+C content was 65.88âmol%. The average nucleotide identity and the Genome-to-Genome Distance Calculator results also showed low relatedness (below 95 and 70â%, respectively) between strain H23T and type strains in the genus Luteimonas. Ubiquinone-8 was the predominant quinone. The major fatty acids were iso-C15â:â0, iso-C16â:â0, iso-C17â:â0 and iso-C17â:â1 ω9c. Polar lipids were dominated by diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and unidentified phospholipids. Low digital DNA-DNA hybridization values, as well as physiological and biochemical differences, such as no casein hydrolysis, being catalase-negative, and tesing positive for cystine arylamidase, α-chymotrypsin and N-acetyl-ß-glucosaminidase, could distinguish strain H23T from its closely related species. Strain H23T is considered to represent a novel species in the genus Luteimonas, for which the name Luteimonas gilva sp. nov. is proposed, with strain H23T (=CCTCC AB 2019255T=KCTC 72593T) as the type strain.
Assuntos
Fazendas , Filogenia , Microbiologia do Solo , Xanthomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Xanthomonadaceae/isolamento & purificaçãoRESUMO
Cervical squamous cell carcinoma develops through a series of stages, including low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), microinvasive squamous cell carcinoma (MISCC), and invasive squamous cell carcinoma (ISCC). The difference between HSIL and MISCC is the appearance of microinvasion, which determines the treatment for patients. However, sometimes it is difficult to differentiate HSIL from MISCC in morphology, and no effective markers are available to help determine microinvasion. Here, we evaluated the expression patterns of podoplanin in cervical tissues by immunohistochemistry staining. Results showed that podoplanin was specifically expressed in a continuous or discontinuous linear pattern within the basal layer of cells from normal cervical squamous epithelium (NS) (100%, 96/96) and HSIL (81%, 57/70). However, its expression was completely absent in microinvasive lesions (0%, 72/72), and the location of podoplanin expression loss was consistent with that of microinvasive lesions. Thus, for HSIL with positive podoplanin expression, the sudden loss of podoplanin represents the occurrence of early invasion. Furthermore, podoplanin was expressed in 3.4% (4/118) of ISCC, and its expression was not correlated with the age of the patient, tumor size, differentiation, FIGO stage, depth of invasion, lymph node, or distant metastasis. The prognosis of patients with positive podoplanin was slightly better than those without it (p > 0.05). Therefore, we found that podoplanin, as a new specific marker for the basal layer cells of cervical squamous epithelium, could assist the diagnosis of microinvasion in cervical squamous cell carcinoma. The specific staining pattern of podoplanin provides the possibility of clinical application in the future.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Glicoproteínas de Membrana/metabolismo , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologiaRESUMO
The patulin biosynthesis is one of model pathways in an understanding of secondary metabolite biology and network novelties in fungi. However, molecular regulation mechanism of patulin biosynthesis and contribution of each gene related to the different catalytic enzymes in the biochemical steps of the pathway remain largely unknown in fungi. In this study, the genetic components of patulin biosynthetic pathway were systematically dissected in Penicillium expansum, which is an important fungal pathogen and patulin producer in harvested fruits and vegetables. Our results revealed that all the 15 genes in the cluster are involved in patulin biosynthesis. Proteins encoded by those genes are compartmentalized in various subcellular locations, including cytosol, nucleus, vacuole, endoplasmic reticulum, plasma membrane and cell wall. The subcellular localizations of some proteins, such as PatE and PatH, are required for the patulin production. Further, the functions of eight enzymes in the 10-step patulin biosynthetic pathway were verified in P. expansum. Moreover, velvet family proteins, VeA, VelB and VelC, were proved to be involved in the regulation of patulin biosynthesis, but not VosA. These findings provide a thorough understanding of the biosynthesis pathway, spatial control and regulation mechanism of patulin in fungi.
Assuntos
Patulina/biossíntese , Penicillium/metabolismo , Vias Biossintéticas , Frutas/microbiologia , Regulação Fúngica da Expressão Gênica , Patulina/genética , Penicillium/genéticaRESUMO
A yellow-coloured bacterial strain, designated ZY74T, was isolated from arsenic contaminated soil (34 mg kg-1) sample collected in Longkou, Hubei Province, PR China. Cells were Gram-stain-negative, aerobic, non-motile and rod-shaped. Strain ZY74T produced round, yellow-pigmented, smooth and opaque colonies. Based on the results of 16S rRNA gene sequence analysis, strain ZY74T was found to be affiliated with members of the genus Chitinophaga. Its closest members were Chitinophagabarathri YLT18T (97.72â%) and Chitinophaganiabensis JS13-10T (97.17â%). The genome size of strain ZY74T was 6.61 Mb, containing 5351 predicted protein-coding genes, with a DNA G+C content of 55.0 mol%. The average nucleotide identity values of strain ZY74T with C. barathri YLT18T and C. niabensis DSM 24787T were 76.12 and 73.32â%, respectively. The digital DNA-DNA hybridization values of strain ZY74T with C. barathri YLT18T and C. niabensis JS13-10T were 20.60 and 19.40â%, respectively. The major respiratory quinone was menaquinone 7 and the predominant fatty acids (>5â%) were iso-C15:0, C16â:â1ω5c and iso-C17â:â03-OH. On the basis of phylogenetic, genotypic, phenotypic and chemotaxonomic characterization, strain ZY74T represents a novel species in the genus Chitinophaga, for which the name Chitinophagalutea sp. nov. is proposed. The type strain is ZY74T (=CCTCC AB2018369T=KCTC 72039T).
Assuntos
Arsênio , Bacteroidetes/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes do Solo , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
An efficient cascade oxysulfonylation of o-vinylanilides with sodium aryl- or alkylsulfinates by a free radical mechanism has been developed, which provides a mild, facile and convenient method for the synthesis of various benzoxazines. Control experiments, including gram-level reactions and mechanistic studies, are involved in the reaction system.
RESUMO
A Gram-stain-negative, aerobic, motile, endospore-forming and rod-shaped bacterium, designated RA17T, was isolated from Dafan, Hubei Province, China. Based on 16S rRNA gene sequence similarity comparisons, strain RA17T was most closely related to Paenibacillus taihuensis THMBG22T (97.4â%), Paenibacillus rhizoryzae ACCC 1ZS3-5T (97.4â%) and Paenibacillus sacheonensis DSM SY01T (96.5â%). Analysis of the rpoB gene also indicated that RA17T had the highest similarity to P. rhizoryzae ACCC 1ZS3-5T (92.3â%), P. taihuensis THMBG22T (88.4â%) and P. sacheonensis DSM SY01T (85.5â%). The DNA-DNA hybridization values between strain RA17T and the two type strains, P. taihuensis THMBG22T and P. rhizoryzae ACCC 1ZS3-5T, were 36.8 and 22.9â%, respectively. Its genome size was 6.17 Mb, comprising 5677 predicted genes with a DNA G+C content of 52.82 molâ%. The major cellular fatty acids were anteiso-C15â:â0, iso-C15â:â0 and iso-C16â:â0. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphoglycolipid, four aminophospholipids, an unidentified phospholipid and an unidentified polar lipid. The major quinone was menaquinone 7. The diagnostic diamino acid of the cell wall was meso-diaminopimelic acid. The low DNA-DNA hybridization values, physiological and biochemical differences, such as growth at 4 °C, acid production from inositol, lack of α-chymotrypsin activity, no casein hydrolysis, and negative for acid production from d-fructose, melibiose and sucrose, could distinguish strain RA17T from its closely related species. Consequently, strain RA17T represents a novel species of the genus Paenibacillus, for which the name Paenibacillusmontanisoli sp. nov. is proposed, with RA17T (=KCTC 33894T=CCTCC AB 2017053T) as the type strain.
Assuntos
Paenibacillus/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
We report the first experimental demonstration of localized flat-band states in optically induced Kagome photonic lattices. Such lattices exhibit a unique band structure with the lowest band being completely flat (diffractionless) in the tight-binding approximation. By taking the advantage of linear superposition of the flat-band eigenmodes of the Kagome lattices, we demonstrate a high-fidelity transmission of complex patterns in such two-dimensional pyrochlore-like photonic structures. Our numerical simulations find good agreement with experimental observations, upholding the belief that flat-band lattices can support distortion-free image transmission.
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We present a simple, yet effective, approach for optical induction of Lieb photonic lattices, which typically rely on the femtosecond laser writing technique. Such lattices are established by judiciously overlapping two sublattices (an "egg-crate" lattice and a square lattice) with different periodicities through a self-defocusing photorefractive medium. Furthermore, taking advantage of the superposition of localized flat-band states inherent in the Lieb lattices, we demonstrate distortion-free image transmission in such two-dimensional perovskite-like photonic structures. Our experimental observations find good agreement with numerical simulations.
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Penicillium species are fungal pathogens that infect crop plants worldwide. P. expansum differs from P. italicum and P. digitatum, all major postharvest pathogens of pome and citrus, in that the former is able to produce the mycotoxin patulin and has a broader host range. The molecular basis of host-specificity of fungal pathogens has now become the focus of recent research. The present report provides the whole genome sequence of P. expansum (33.52 Mb) and P. italicum (28.99 Mb) and identifies differences in genome structure, important pathogenic characters, and secondary metabolite (SM) gene clusters in Penicillium species. We identified a total of 55 gene clusters potentially related to secondary metabolism, including a cluster of 15 genes (named PePatA to PePatO), that may be involved in patulin biosynthesis in P. expansum. Functional studies confirmed that PePatL and PePatK play crucial roles in the biosynthesis of patulin and that patulin production is not related to virulence of P. expansum. Collectively, P. expansum contains more pathogenic genes and SM gene clusters, in particular, an intact patulin cluster, than P. italicum or P. digitatum. These findings provide important information relevant to understanding the molecular network of patulin biosynthesis and mechanisms of host-specificity in Penicillium species.
Assuntos
Genômica , Malus/microbiologia , Família Multigênica , Patulina/metabolismo , Penicillium/genética , Doenças das Plantas/microbiologia , Sequência de Aminoácidos , Sequência de Bases , Frutas/microbiologia , Técnicas de Inativação de Genes , Genes Reporter , Dados de Sequência Molecular , Patulina/genética , Penicillium/citologia , Penicillium/metabolismo , Penicillium/patogenicidade , Fenótipo , Filogenia , Metabolismo Secundário , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de Sequência de RNA , VirulênciaRESUMO
We demonstrate self-trapping and rotation of higher-band dipole and quadruple-like gap solitons by single-site excitation in a two-dimensional square photonic lattice under self-focusing nonlinearity. Experimental results show that the second-band dipole gap solitons reside in the first photonic (Bragg reflection) gap, whereas the quadruple-like gap solitons are formed in an even higher photonic gap, resulting from modes of the third-band. Moreover, both dipole and quadruple-like gap solitons exhibit dynamical rotation around the lattice principle axes and the direction of rotation is changing periodically during propagation, provided that they are excited under appropriate initial conditions. In the latter case, the nonlinear rotation is accompanied by periodic transitions between quadruple and doubly-charged vortex states. Our numerical simulations find good agreement with the experimental observations.
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In previous studies of hand, foot, and mouth disease patients fatally infected with enterovirus 71 (EV71), the distribution of viral protein, but not the genome, was determined. To understand the pathogenesis of EV71, however, it is important to investigate the spread of the viral genome. There have been no pathological studies of in situ EV71 viral RNA in inflammatory cells infiltrating various tissues of fatal cases. We therefore first investigated the distribution and classification of inflammatory cells in various tissues and then performed in situ EV71 RNA hybridization in these tissues to better understand the pathogenesis of EV71 infection. EV71 RNA was found mainly in inflammatory cells infiltrating the central nervous system (CNS), intestines, lungs, and tonsils. Most EV71 RNA-positive inflammatory cells in the CNS were macrophages/microglia and neutrophils infiltrating the perivascular cuffing, microglial nodule, neuronophagia, and meninges. CD68+ macrophages and CD15+ neutrophils were diffusely distributed in tissues with severe pathological changes. This study demonstrates the presence of EV71 RNA in inflammatory cells infiltrating tissues in fatally infected patients. Our findings suggest that fatal EV71 infection with extensive infiltration of macrophages/microglia and neutrophils into the CNS results in severe neurological lesions.
Assuntos
Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Imunidade Celular/fisiologia , Inflamação/virologia , RNA Viral/isolamento & purificação , Genoma Viral , Doença de Mão, Pé e Boca/mortalidade , Humanos , Hibridização In Situ , Distribuição TecidualRESUMO
OBJECTIVES: To investigate whether the choline-containing compounds (Cho) obtained from three-dimensional (1)H magnetic resonance (MR) spectroscopy can differentiate endometrial cancer (ECa) from benign lesions in endometria or in submucosa (BLs-ESm) and is associated with the aggressiveness of ECa. METHODS: Fifty-seven patients (ECa, 38; BLs-ESm, 19) underwent preoperative multi-voxel MR spectroscopy at 3.0 T. The ratio of the sum of the Cho peak integral to the sum of the unsuppressed water peak integral (Cho/water) and the coefficient of variation (CV) used to describe the variability of Cho/water in one lesion were calculated. RESULTS: Mean Cho/water (±standard deviation [SD]) was (3.02 ± 1.43) × 10(-3) for ECa and (1.68 ± 0.33) × 10(-3) for BLs-ESm (p < 0.001). Mean Cho/water was (4.42 ± 1.53) × 10(-3) for type II ECa and (2.65 ± 1.17) × 10(-3) for type I ECa (p = 0.001). There were no significant differences among different stages of ECa (p = 0.107) or different grades of ECa (p = 0.142). The Cho/water was positively correlated with tumour stage (r = 0.386, p = 0.017) and size (r = 0.333, p = 0.041). The CV was also positively correlated with tumour stage (r = 0.537, p = 0.001) and size (r = 0.34, p = 0.037). CONCLUSION: The Cho/water can differentiate ECa from BLs-ESm and differentiate type II from type I ECa, but cannot differentiate different stages of ECa or different grades of ECa. Cho/water increased with the increase of tumour stage and size. KEY POINTS: ⢠First report to attempt to assess ECa aggressiveness with magnetic resonance spectroscopy (MRS). ⢠MRS can differentiate type I from type II ECa. ⢠MRS can differentiate ECa from BLs-ESm. ⢠MRS cannot differentiate different stages of ECa or different grades of ECa. ⢠Cho/water increased with the increase of tumour stage and size.
Assuntos
Colina/análise , Neoplasias do Endométrio/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Adulto , Idoso , Biomarcadores Tumorais/análise , Diagnóstico Diferencial , Neoplasias do Endométrio/química , Neoplasias do Endométrio/cirurgia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Período Pré-Operatório , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
Thiosulfonylation and selenosulfonylation of vinyl azides with thiosulfonates and selenosulfonates were achieved using Cu(dap)2Cl as a photosensitizer under visible-light irradiation. This reaction is the application of a vinyl azide substrate in a group transfer radical addition (GTRA) reaction, through ß-difunctionalization, to obtain a variety of unsymmetric difunctionalized N-unprotected enamines.
RESUMO
The memristor is the building block of neuromorphic computing. We report a new type of nanofluidic memristor based on the principle of elastic strain on polymer nanopores. With nanoparticles absorbed at the wall of a single conical polymer nanopore, we find a pinched hysteresis of the current within a scanning frequency range of 0.01-0.1 Hz, switching to a diode below 0.01 Hz and a resistor above 0.1 Hz. We attribute the current hysteresis to the elastic strain at the tip side of the nanopore, caused by electrical force on the particles adsorbed at the inner wall surface. Our simulation and analytical equations match well with experimental results, with a phase diagram for predicting the system transitions. We demonstrate the plasticity of our nanofluidic memristor to be similar to a biological synapse. Our findings pave a new way for ionic neuromorphic computing using nanofluidic memristors.
RESUMO
A critical transcription factor, PacC, modulates the expression of fungal pH signaling. Although PacC-mediated environmental pH has been reported to regulate the growth and pathogenicity of postharvest pathogens, the involvement of PacC in sucrose metabolism, sugar transport, and the pentose phosphate pathway (PPP) in different zones of decayed fruit remains unclear. Our work showed that the inoculation with a PePacC deletion strain of Penicillium expansum (ΔPePacC) accelerated sucrose catabolism and glucose and fructose accumulation in different zones of apple fruit. This was attributed to an increase in sucrose metabolism enzyme activities and up-regulation of the sugar transporter protein-related gene expression. Moreover, ΔPePacC inoculation increased the PPP-related enzyme activities and the levels of nicotinamide adenine dinucleotide phosphate (NADPH) and NADP+. In conclusion, PacC modulates sucrose metabolism, sugar transport, and the PPP in apple fruit by mediating dynamic changes in environmental pH, thereby enhancing fruit disease resistance.