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Type C hepatic encephalopathy (HE) is a condition characterized by brain dysfunction caused by liver insufficiency and/or portal-systemic blood shunting, which manifests as a broad spectrum of neurological or psychiatric abnormalities, ranging from minimal HE (MHE), detectable only by neuropsychological or neurophysiological assessment, to coma. Though MHE is the subclinical phase of HE, it is highly prevalent in cirrhotic patients and strongly associated with poor quality of life, high risk of overt HE, and mortality. It is, therefore, critical to identify MHE at the earliest and timely intervene, thereby minimizing the subsequent complications and costs. However, proper and sensitive diagnosis of MHE is hampered by its unnoticeable symptoms and the absence of standard diagnostic criteria. A variety of neuropsychological or neurophysiological tests have been performed to diagnose MHE. However, these tests are nonspecific and susceptible to multiple factors (eg, aging, education), thereby limiting their application in clinical practice. Thus, developing an objective, effective, and noninvasive method is imperative to help detect MHE. Magnetic resonance imaging (MRI), a noninvasive technique which can produce many objective biomarkers by different imaging sequences (eg, Magnetic resonance spectroscopy, DWI, rs-MRI, and arterial spin labeling), has recently shown the ability to screen MHE from NHE (non-HE) patients accurately. As advanced MRI techniques continue to emerge, more minor changes in the brain could be captured, providing new means for early diagnosis and quantitative assessment of MHE. In addition, the advancement of artificial intelligence in medical imaging also presents the potential to mine more effective diagnostic biomarkers and further improves the predictive efficiency of MHE. Taken together, advanced MRI techniques may provide a new perspective for us to identify MHE in the future. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.
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BACKGROUNDS: Lysine 2-hydroxyisobutyrylation (Khib) is a newly discovered posttranslational modification (PTM) and has been identified in several prokaryotic and eukaryotic organisms. Fusarium graminearum, a major pathogen of Fusarium head blight (FHB) in cereal crops, can cause considerable yield loss and produce various mycotoxins that threaten human health. The application of chemical fungicides such as tebuconazole (TEC) remains the major method to control this pathogen. However, the distribution of Khib in F. graminearum and whether Khib is remodified in response to fungicide stress remain unknown. RESULTS: Here, we carried out a proteome-wide analysis of Khib in F. graminearum, identifying the reshaping of the lysine 2-hydroxyisobutyrylome by tebuconazole, using the most recently developed high-resolution LC-MS/MS technique in combination with high-specific affinity enrichment. Specifically, 3501 Khib sites on 1049 proteins were identified, and 1083 Khib sites on 556 modified proteins normalized to the total protein content were changed significantly after TEC treatment. Bioinformatics analysis showed that Khib proteins are involved in a wide range of biological processes and may be involved in virulence and deoxynivalenol (DON) production, as well as sterol biosynthesis, in F. graminearum. CONCLUSIONS: Here, we provided a wealth of resources for further study of the roles of Khib in the fungicide resistance of F. graminearum. The results enhanced our understanding of this PTM in filamentous ascomycete fungi and provided insight into the remodification of Khib sites during azole fungicide challenge in F. graminearum.
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Fusarium , Cromatografia Líquida , Humanos , Lisina/metabolismo , Doenças das Plantas , Proteômica , Espectrometria de Massas em Tandem , TriazóisRESUMO
Blood glucose monitoring is of great significance to diabetic patients, and the development of rapid, accurate and real-time glucose detection technology has become a research hotspot nowadays. This study introduces the concept and classification of the enzyme-free glucose sensor, expounds enzymefree glucose sensor electrode characterization methods and the application progress of different materials in enzyme-free blood glucose sensors. Meanwhile, some problems of enzyme-free glucose sensor existing in the current research and its future application prospects also will be discussed.
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Automonitorização da Glicemia , Glicemia , Eletrodos , Glucose , Humanos , Monitorização FisiológicaRESUMO
A total of 191 soil samples from Hangzhou, China, were submitted to detect non-wild-type (non-WT) Aspergillus fumigatus and its associated mechanisms. There were 2 (4.7%), 13 (12.4%), and 31 (23.1%) isolates identified as non-WT in 2014, 2016, and 2018, respectively. The resistant mutations of TR34/L98H, TR46/Y121F/T289A, and TR34/L98H/S297T/F495I were found in 3, 5, and 5 non-WT isolates. The G448S mutation, previously only found in clinical settings, was detected in A. fumigatus from soil samples.
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Aspergillus fumigatus , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Azóis/farmacologia , China , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Testes de Sensibilidade MicrobianaRESUMO
A novel synthetic protocol for the construction of eight-membered heterocycles by intramolecular palladium-catalyzed ortho C-H activation/C-C cyclization was proposed. With protosappanin A as the lead compound, 25 derivatives of 8-azaprotosappanin A were prepared in good yields by this protocol. Besides, a plausible reaction mechanism of the intramolecular cyclization was proposed. This strategy could be widely used in the synthesis of some natural products and drugs with large heterocycles due to the fast reaction rate and the mild conditions. In vitro antimicrobial activities of the synthesized compounds were assessed against the strains of Gram-positive bacteria and linezolid and ciprofloxacin were selected as the standard drugs. Some of the synthesized compounds were found to have excellent antibacterial activities.
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A sensitive and effective method for the simultaneous determination of residues from a new fungicide, oxathiapiprolin, and its metabolites (IN-E8S72 and IN-WR791) in soil, water, and sediment, was developed using ultra high performance liquid chromatography with tandem mass spectrometry. Three compounds were extracted from water, soil, and sediment by using acetonitrile and different proportions of formic acid aqueous solution (1% v/v for water; 2% v/v for soil; and sediment), and were cleaned with octadecylsilane. The target compounds were determined within 5 min using an electrospray ionization source in the positive mode for oxathiapiprolin and in the negative mode for the two metabolites. The limits of quantification for all the three compounds were 0.1 µg/kg in water and 1 µg/kg in soil and sediment. Recovery studies were performed using three spiked levels (0.1, 1, and 10 µg/kg for water; 1, 10, and 50 µg/kg for soil and sediment). The overall average recoveries ranged from 64.8 to 112.7% with all intra- and interday relative standard deviation values below 19.4 and 19.1%, respectively. The method validation confirmed that the proposed method was convenient and reliable for determining residual oxathiapiprolin and its metabolites in soil, water, and sediments.
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Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/química , Sedimentos Geológicos/química , Hidrocarbonetos Fluorados/química , Pirazóis/química , Poluentes do Solo/química , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/química , Fracionamento Químico , China , Resíduos de Drogas/química , Resíduos de Drogas/isolamento & purificação , Fungicidas Industriais/isolamento & purificação , Hidrocarbonetos Fluorados/isolamento & purificação , Pirazóis/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
Background: Observational research and medical trials have suggested a connection between gut microbiota and glioblastoma, but it remains unclear if the relationship is causal. Method: A two-sample Mendelian randomization (MR) study was conducted by employing data from the MiBioGen consortium's largest genome-wide association study (n=18340) and the FinnGen consortium R8 release information (162 cases and 256,583 controls). Inverse variance weighted (IVW), weighted median estimator (WME), weighted model, MR-Egger, simple mode, and MR-PRESSO were used to determine the causal relationship between gut microbiota and glioblastoma. Reverse MR analysis was also performed on bacteria identified as causally related to glioblastoma. Results: Seven causal relationships were identified between genetic liability in the gut microbiota and glioblastoma, involving various bacterial families and genera. No significant causal effect was found on gut microbiota from glioblastoma, and no significant heterogeneity of instrumental variables (IVs) or horizontal pleiotropy was observed. Conclusion: A two-sample MR analysis reveals a causal association between the gut microbiota and glioblastoma, highlighting the need for more investigation to comprehend the processes behind this association.
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Sarcomatoid carcinoma (SC) is a rare primary malignant tumor in which both carcinomatous and sarcomatous elements occur. It can occur in many different organs and anatomical locations, such as the skin, thyroid gland, bone, urinary tract, breast, pancreas, liver and other areas. Of them, pulmonary sarcomatoid carcinoma (PSC) is a rare malignant cancer composed of sarcoma and sarcoma-like tumors with spindle or giant cell features. Here a case of a 75-year-old Chinese man with a six-month history of cough and hemoptysis is reported. Chest X-ray showed a tumor shadow in the left lung field. Chest computed tomography (CT) scan showed a lobulated mass in his left hilum and even the left pulmonary artery. Pleomorphic interstitial cells were found by bronchoscopic brushing. To establish a definitive diagnosis for PSC, a left pneumonectomy was performed. The pathological stage was IIB (pT2N1M0) based on the tumor node metastasis (TNM) staging system. The tumor's pathology, histology, immunohistochemistry and treatment methods are discussed.
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As one of the future's most promising clean energy sources, solar energy is the key to developing renewable energy. The randomness of solar irradiance can affect the efficiency of photovoltaic power generation, which makes photovoltaic power generation planning extremely difficult. The main goal of this study is to accurately predict solar irradiance and establish a prediction model with meteorological characteristics to improve prediction accuracy. This paper proposes a convolutional neural network (CNN) and attention mechanism-based long short-term memory network (A-LSTM) to predict solar irradiance the next day. In addition, the prediction accuracy is further improved by combining similar day analyses. A similar day prediction model is constructed by selecting solar energy data from Andhra Pradesh, India. The experimental results show that the method proposed in this paper can predict solar irradiance more accurately, providing a new idea for photovoltaic power generation planning.
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Deoxynivalenol (DON) is an important virulence factor of the Fusarium head blight of wheat and threatens the health of humans. The effect of fungicides on DON production after stressing wheat to produce H2O2 and the effect of nontarget pesticides on DON accumulation are largely unknown. Five pesticides were selected to explore the effect of pesticide-induced oxidative stress on DON production in vitro and in vivo. Epoxiconazole and hexaconazole significantly induced an increase in H2O2 in vitro, and H2O2 further stimulated the production of DON and the expression of the Tri5 gene. Imidacloprid, isoproturon, and mesosulfuron-methyl had no direct effect in vitro. All pesticides activated the activities of superoxide dismutase, catalase, and peroxidase in wheat and caused the excessive accumulation of H2O2. However, excessive H2O2 did not stimulate the accumulation of DON. Imidacloprid indirectly stimulated the production of DON in vivo, which may be due to its impact on the secondary metabolism of wheat. In brief, pesticide-induced H2O2 in vitro is an important factor in stimulating DON production, but the stressed physiological H2O2 in wheat is not sufficient to stimulate DON production. The bioaccumulation results indicated that imidacloprid and epoxiconazole increase the risk of DON contamination, especially under field spraying conditions.
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The adsorption-desorption and degradation characteristics of two widely applied fungicides, imazalil and penflufen, and the responses of soil bacterial diversity, structure, function, and interaction after long-term exposure were systemically studied in eight different soils. The adsorption ability of imazalil in soil was significantly higher than that of penflufen. Both imazalil and penflufen degraded slowly in most soils following the order: imazalil > penflufen, with soil pH, silt, and clay content being the potential major influencing factors. Both imazalil and penflufen obviously inhibited the soil microbial functional diversity, altered the soil bacterial community and decreased its diversity. Although exposure to low and high concentrations of imazalil and penflufen strengthened the interactions among the soil bacterial communities, the functional diversity of the co-occurrence network tended to be simple at high concentrations, especially in penflufen treatment. Both imazalil and penflufen markedly disturbed soil nitrogen cycling, especially penflufen seriously inhibited most nitrogen cycling processes, such as nitrogen fixation and nitrification. Meanwhile, sixteen and ten potential degradative bacteria of imazalil and penflufen, respectively, were found in soils, including Kaistobacter and Lysobacter. Collectively, the long-term application of imazalil and penflufen could cause residual accumulation in soils and subsequently result in serious negative effects on soil ecology.
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Fungicidas Industriais , Solo , Fungicidas Industriais/toxicidade , Bactérias , NitrogênioRESUMO
BACKGROUND: Brain functional network disruption and neurocognitive dysfunction have been reported in obstructive sleep apnea (OSA) patients. Nevertheless, most research studies static networks, while brain evolution continues dynamically. PURPOSE: To investigate the characteristics of dynamical networks in moderate-to-severe OSA patients using multilayer network analysis of dynamic networks and compare their association with neurocognitive function. METHODS: Twenty-seven moderate-to-severe OSA patients and twenty-five matched healthy controls (HCs) who completed the examination of the Epworth sleepiness scale (ESS), neurocognitive function, polysomnography, and functional magnetic resonance imaging (fMRI) were prospectively included. The dynamic variations of resting-state functional networks in both groups were described via network switching rate. Switching rates and their correlation with clinical parameters were analyzed. RESULTS: At the global level, network switching rates were notably lower in the OSA group than in the HCs group (p = 0.002). More specifically, the differences include the default mode network (DMN), auditory network, and ventral attention network at the subnetwork level, and the right rolandic operculum, left middle temporal gyrus, and right precentral gyrus at the nodal level. Furthermore, these altered switching rates have a close correlation with ESS, sleep parameters, and neurocognitive function. CONCLUSION: Patients with moderate-to-severe OSA showed lower network switching rates, especially in the DMN, auditory network, and ventral attention network. The disruption of dynamic functional networks may be a potentially crucial mechanism of neurocognitive dysfunction in moderate-to-severe OSA patients.
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Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/diagnóstico , Encéfalo , Sono , Lobo Temporal , PolissonografiaRESUMO
The lithiation/delithiation properties of α-Si3 N4 and ß-Si3 N4 are compared and the carbon coating effects are examined. Then, ß-Si3 N4 at various fractions is used as the secondary phase in a Si anode to modify the electrode properties. The incorporated ß-Si3 N4 decreases the crystal size of Si and introduces a new NSiO species at the ß-Si3 N4 /Si interface. The nitrogen from the milled ß-Si3 N4 diffuses into the surface carbon coating during the carbonization heat treatment, forming pyrrolic nitrogen and CNO species. The synergistic effects of combining ß-Si3 N4 and Si phases on the specific capacity are confirmed. The operando X-ray diffraction and X-ray photoelectron spectroscopy data indicate that ß-Si3 N4 is partially consumed during lithiation to form a favorable Li3 N species at the electrode. However, the crystalline structure of the hexagonal ß-Si3 N4 is preserved after prolonged cycling, which prevents electrode agglomeration and performance deterioration. The carbon-coated ß-Si3 N4 /Si composite anode shows specific capacities of 1068 and 480 mAh g-1 at 0.2 and 5 A g-1 , respectively. A full cell consisting of the carbon-coated ß-Si3 N4 /Si anode and a LiNi0.8 Co0.1 Mn0.1 O2 cathode is constructed and its properties are evaluated. The potential of the proposed composite anodes for Li-ion battery applications is demonstrated.
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In this study, bio-based ionic liquid prepared from ricinoleic acid and choline was firstly used as additive in lithium base grease. The characterization and tribological performance of the prepared ionic liquid ([cho][ricinoleic]) as additive in grease were studied compared with the traditional ionic liquid such as L-P104. All the concentrations showed promising friction-reducing and anti-wear properties, though a 3% concentration has superior lubricating properties than others. Furthermore, [cho][ricinoleic]) can greatly enhance the lubrication capability of lithium base greaseunder different frequency and load at room temperature. Although L-P104 showed good lubricating performance than [cho][ricinoleic] at 150°C, the chosen formulation (1.5% [cho][ricinoleic] + 1.5% L-P104) could have better synergism at high and room temperature, which could be a good supplement to ionic liquid as grease additive. Thin films formed according to the results of SEM and XPS were attributed to be the main account for the preferable tribological properties of [cho][ricinoleic] in lithium base grease.
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Líquidos Iônicos , Lítio , Colina , Hidrocarbonetos , Lubrificantes , Ácidos RicinoleicosRESUMO
Fusarium graminearum is the predominant causal agent of cereal Fusarium head blight disease (FHB) worldwide. The application of chemical fungicides such as azole antifungals is still the primary method for FHB control. However, to date, our knowledge of transcriptional regulation in the azole resistance of F. graminearum is quite limited. In this study, we identified and functionally characterized a Zn(II)2-Cys6 transcription factor FgAtrR in F. graminearum. We constructed a FgAtrR deletion mutant and found that deletion of FgAtrR resulted in faster radial growth with serious pigmentation defects, significantly reduced conidial production, and an inability to form perithecia. The pathogenicity of the ΔFgAtrR mutant on wheat spikes and corn silks was severely impaired with reduced deoxynivalenol production, while the tolerance to prochloraz and propiconazole of the deletion mutant was also significantly decreased. RNA-seq indicated that many metabolic pathways were affected by the deletion of FgAtrR. Importantly, FgAtrR could regulate the expression of the FgCYP51A and ABC transporters, which are the main contributors to azole resistance. These results demonstrated that FgAtrR played essential roles in asexual and sexual development, DON production, and pathogenicity, and contributed to intrinsic resistance to azole fungicides in F. graminearum. This study will help us improve the understanding of the azole resistance mechanism in F. graminearum.
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Water-glycerol as one promising alternative for mineral oil can be applied as a green lubricant but has poor lubricity and strong corrosivity. It is desirable to design multifunctional water soluble lubricant additives. Protic ionic liquids (PILs) show considerable potential due to their facile preparation and environmental friendliness. Herein, an eco-friendly PIL ([osar][mea]) was facilely prepared from an amino acid derivate and investigated its anticorrosion and lubrication performances in the glycerol solution. Furthermore, the wear traces were measured using SEM/EDS and XPS for exploring the lubrication mechanism. The prepared PIL can rapidly increase the corrosion inhibition ability of water-glycerol as its concentration increases over CMC, and the anion playing a key role in the light of DFT calculations. Furthermore, [osar][mea] can greatly enhance the lubrication capability especially of water-glycerol while its concentration in the glycerol solution exceed 3%. The lubricity reduced with the increasing load. By the means of using SEM/EDS and XPS evaluation of the wear traces, we can speculate the possible lubrication mechanism may be the presence of the [osar][mea] adsorption film and the tribofilm containing complex nitrogen compounds.
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Aminoácidos/química , Glicerol , Líquidos Iônicos/química , Lubrificantes/química , Água , Adsorção , Lubrificação , SolubilidadeRESUMO
Residual injury of atrazine to the succeeding crops has been frequently reported. It is necessary to find a solution for the detoxification of atrazine contaminated soil. A high-efficient bacterial strain Arthrobacter sp. C2 for atrazine degradation was isolated in this study. The genomic information of the isolate C2, and its degradation characteristics and potential application in detoxification of atrazine contaminated soil were investigated. The results indicated that the isolate C2 genome contained 4,305,216 bp nucleotides, three plasmids, and 4705 coding genes. The degradation rates of atrazine at levels of 1, 10, 100 mg/L by the isolate C2 were 0.34, 1.94, 18.64 mg/L/d, respectively. The optimum temperature and pH for the isolate C2 to degrade atrazine were 30 °C and 7.0-9.0. Based on the metabolites detected by UPLC-TOF-MS/MS and genome annotation of the isolate C2, a common metabolic pathway of atrazine was proposed as that atrazine is firstly dechlorinated into hydroxyatrazine, and subsequently to N-isopropylammelide via dealkylation, and ultimately deaminated to cyanuric acid. Introduction of the isolate C2 into soil can enhance degradation of atrazine and thus eliminate the toxic effect of this herbicide on wheat growth. Our results indicate that the strain C2 could be a potential bioresource for bioremediation of atrazine contaminated soil.
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Arthrobacter , Atrazina , Herbicidas , Poluentes do Solo , Arthrobacter/genética , Atrazina/análise , Atrazina/toxicidade , Biodegradação Ambiental , Herbicidas/análise , Herbicidas/toxicidade , Microbiologia do Solo , Poluentes do Solo/análise , Espectrometria de Massas em TandemRESUMO
OBJECTIVE: To investigate the migration and distribution of CTL (cytotoxic T lymphocyte) and CIK (cytokine-induced killer) cells in gastric tumor model. METHODS: Subcutaneous gastric tumor model was established by BGC-823 cancer cells in nude mice. Both CTL and CIK cells were labeled with 99Tc(m) directly and then inoculated into nude mice with subcutaneous tumor by intravenous injection separately. Three mice of each group were evaluated by single-photon emission computerized tomography (SPECT) at 1 h, 6 h and 24 h post-inoculation. After SPECT imaging, 3 mice in each group were sacrificed and got samples of the tumor, liver, spleen, kidney, lung, intestine, etc. The tissue samples were weighed and radioactivity was determined with a well-type scintillation counter. The accumulation of labeled CTL and CIK cells in tissues were expressed as %ID/g (percentage activity of injection dose per gram of tissue) and T/NT (tumor/non-tumor) values were analyzed. RESULTS: The tracing of both cells in SPECT showed a clear migration path away from the injection point to solid tumor, and can be detected in all organs and tissues such as liver, spleen, kidney, lung and intestine, etc not long after injection. The %ID/g peak values of CTL in organs from the highest to the lowest were as follows: tumor (7.79 +/- 0.46), liver (4.12 +/- 0.51), intestine (2.71 +/- 0.16), kidney (1.44 +/- 0.25), spleen (1.24 +/- 0.12), kidney (1.12 +/- 0.11), and all the T/NTs were above 1. The %ID/g peak values of CIK cells in organs from the highest to the lowest were as follows: liver (6.64 +/- 0.67), tumor (5.47 +/- 0.87), intestine (3.55 +/- 0.23), kidney (2.34 +/- 0.41), spleen (1.45 +/- 0.17), lung (1.27 +/- 0.21), and T/NTs > 1 except for liver. After injection, the %ID/g values of tumor in CTL group were 2.35 +/- 0.28 (1 h), 4.58 +/- 0.52 (6 h) and 7.79 +/- 0.46 (24 h) respectively while the %ID/g values of tumor in CIK group 2.23 +/- 0.46 (1 h), 3.25 +/- 0.70 (6 h) and 5.47 +/- 0.87 (24 h) respectively. At 24 h point, the %ID/g of CTL in tumor was much higher than CIK cells (P < 0.05). CONCLUSION: The definite directional tumor-targeting capacity of CTL and CIK cells in tumor-bearing nude mice is promising.
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Movimento Celular , Células Matadoras Induzidas por Citocinas/citologia , Neoplasias Gástricas/imunologia , Linfócitos T Citotóxicos/citologia , Animais , Linhagem Celular Tumoral , Células Matadoras Induzidas por Citocinas/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Linfócitos T Citotóxicos/imunologia , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
Triazole-resistance in Aspergillus fumigatus is widespread. We evaluated whether triazole-resistance in A. fumigatus and its related cyp51A mutations, induced by a combination of the triazole fungicides difenoconazole and propiconazole, differs from resistance induced by the individual fungicides. Both difenoconazole and propiconazole can induce triazole-resistance in A. fumigatus. Resistance is much easier induced by formulated fungicides or a combination of these two fungicides compared with standard fungicides or individual fungicides, respectively. Six different mutations (G138S, G138D, H147Y, I246M, M263I and D430N) were identified in the induced resistant strains. The H147Y, I246M and M263I mutations were associated with triazole-resistance. This implies that the application of a combination of difenoconazole and propiconazole may result in higher triazole-resistance in A. fumigatus and more mutations in the cyp51A gene.
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Aspergillus fumigatus , Fungicidas Industriais , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Sistema Enzimático do Citocromo P-450/genética , Dioxolanos , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Fungicidas Industriais/farmacologia , Mutação , Triazóis/farmacologiaRESUMO
Residual acetochlor and atrazine in soils, resulting from their extensive application to maize plants, may affect product safety of the ultimate wheat crop. To determine the potential uptake and accumulation of acetochlor and atrazine by wheat plants, the uptake mechanism, translocation, and subcellular distribution of these two herbicides were studied through hydroponic experiments (10 mg L-1). The results indicated that acetochlor can be taken up through the apoplastic pathway and can accumulate in wheat roots with little upward translocation. However, atrazine could be taken up by roots through the symplastic pathway and subsequently transported to the stems and leaves. Little upward translocation of acetochlor in wheat plants was due to its preferential distribution into root organelles with higher lipid contents. Conversely, the low bioconcentration of atrazine in root organelles and cell walls after uptake led to its easy upward translocation. Uptake of acetochlor and atrazine by wheat roots and the distribution of atrazine to the stems and leaves were predicted well by using the partition-limited model. The obtained results indicated that residual atrazine in soil may be taken up by wheat roots and acropetally translocated, thereby posing a threat to product safety of wheat.