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1.
Plant Cell ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963880

RESUMO

Nucleus-encoded chloroplast proteins can be transported via the secretory pathway. The molecular mechanisms underlying the trafficking of chloroplast proteins between the intracellular compartments are largely unclear, and a cargo sorting receptor has not previously been identified in the secretory pathway. Here we report a cargo sorting receptor that is specifically present in Viridiplantae and mediates the transport of cargo proteins to the chloroplast. Using a forward genetic analysis, we identified a gene encoding a transmembrane protein (MtTP930) in barrel medic (Medicago truncatula). Mutation of MtTP930 resulted in impaired chloroplast function and a dwarf phenotype. MtTP930 is highly expressed in the aerial parts of the plant and is localized to the ER exit sites (ERESs) and Golgi. MtTP930 contains typical cargo sorting receptor motifs, interacts with Sar1, Sec12 and Sec24, and participates in coat protein II (COPII) vesicular transport. Importantly, MtTP930 can recognize the cargo proteins plastidial N-glycosylated nucleotide pyrophosphatase/ phosphodiesterase (MtNPP) and α-carbonic anhydrase (MtCAH) in the ER, and then transport them to the chloroplast via the secretory pathway. Mutation of a homolog of MtTP930 in Arabidopsis (Arabidopsis thaliana) resulted in a similar dwarf phenotype. Furthermore, MtNPP-GFP failed to localize to chloroplasts when transgenically expressed in Attp930 protoplasts, implying that these cargo sorting receptors are conserved in plants. These findings fill a gap in our understanding of the mechanism by which chloroplast proteins are sorted and transported via the secretory pathway.

2.
Plant Cell ; 36(7): 2629-2651, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38552172

RESUMO

S-acylation is a reversible post-translational modification catalyzed by protein S-acyltransferases (PATs), and acyl protein thioesterases (APTs) mediate de-S-acylation. Although many proteins are S-acylated, how the S-acylation cycle modulates specific biological functions in plants is poorly understood. In this study, we report that the S-acylation cycle of transcription factor MtNAC80 is involved in the Medicago truncatula cold stress response. Under normal conditions, MtNAC80 localized to membranes through MtPAT9-induced S-acylation. In contrast, under cold stress conditions, MtNAC80 translocated to the nucleus through de-S-acylation mediated by thioesterases such as MtAPT1. MtNAC80 functions in the nucleus by directly binding the promoter of the glutathione S-transferase gene MtGSTU1 and promoting its expression, which enables plants to survive under cold stress by removing excess malondialdehyde and H2O2. Our findings reveal an important function of the S-acylation cycle in plants and provide insight into stress response and tolerance mechanisms.


Assuntos
Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Medicago truncatula , Proteínas de Plantas , Fatores de Transcrição , Medicago truncatula/genética , Medicago truncatula/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Resposta ao Choque Frio/genética , Acilação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Temperatura Baixa , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética
3.
Mol Microbiol ; 121(5): 971-983, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480679

RESUMO

Increasing evidence suggests that DNA phosphorothioate (PT) modification serves several purposes in the bacterial host, and some restriction enzymes specifically target PT-DNA. PT-dependent restriction enzymes (PDREs) bind PT-DNA through their DNA sulfur binding domain (SBD) with dissociation constants (KD) of 5 nM~1 µM. Here, we report that SprMcrA, a PDRE, failed to dissociate from PT-DNA after cleavage due to high binding affinity, resulting in low DNA cleavage efficiency. Expression of SBDs in Escherichia coli cells with PT modification induced a drastic loss of cell viability at 25°C when both DNA strands of a PT site were bound, with one SBD on each DNA strand. However, at this temperature, SBD binding to only one PT DNA strand elicited a severe growth lag rather than lethality. This cell growth inhibition phenotype was alleviated by raising the growth temperature. An in vitro assay mimicking DNA replication and RNA transcription demonstrated that the bound SBD hindered the synthesis of new DNA and RNA when using PT-DNA as the template. Our findings suggest that DNA modification-targeting proteins might regulate cellular processes involved in DNA metabolism in addition to being components of restriction-modification systems and epigenetic readers.


Assuntos
Replicação do DNA , Proteínas de Escherichia coli , Escherichia coli , Enxofre , Escherichia coli/metabolismo , Escherichia coli/genética , Enxofre/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , DNA Bacteriano/metabolismo , Enzimas de Restrição do DNA/metabolismo , Ligação Proteica , DNA/metabolismo , Sítios de Ligação
4.
BMC Genomics ; 23(Suppl 5): 863, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936055

RESUMO

BACKGROUND: Genomic variants of the disease are often discovered nowadays through population-based genome-wide association studies (GWAS). Identifying genomic variations potentially underlying a phenotype, such as hypertension, in an individual is important for designing personalized treatment; however, population-level models, such as GWAS, may not capture all the important, individualized factors well. In addition, GWAS typically requires a large sample size to detect the association of low-frequency genomic variants with sufficient power. Here, we report an individualized Bayesian inference (IBI) algorithm for estimating the genomic variants that influence complex traits, such as hypertension, at the level of an individual (e.g., a patient). By modeling at the level of the individual, IBI seeks to find genomic variants observed in the individual's genome that provide a strong explanation of the phenotype observed in this individual. RESULTS: We applied the IBI algorithm to the data from the Framingham Heart Study to explore the genomic influences of hypertension. Among the top-ranking variants identified by IBI and GWAS, there is a significant number of shared variants (intersection); the unique variants identified only by IBI tend to have relatively lower minor allele frequency than those identified by GWAS. In addition, IBI discovered more individualized and diverse variants that explain hypertension patients better than GWAS. Furthermore, IBI found several well-known low-frequency variants as well as genes related to blood pressure that GWAS missed in the same cohort. Finally, IBI identified top-ranked variants that predicted hypertension better than GWAS, according to the area under the ROC curve. CONCLUSIONS: The results support IBI as a promising approach for complementing GWAS, especially in detecting low-frequency genomic variants as well as learning personalized genomic variants of clinical traits and disease, such as the complex trait of hypertension, to help advance precision medicine.


Assuntos
Estudo de Associação Genômica Ampla , Hipertensão , Humanos , Estudo de Associação Genômica Ampla/métodos , Teorema de Bayes , Polimorfismo de Nucleotídeo Único , Fenótipo , Hipertensão/genética , Genômica
5.
Plant Biotechnol J ; 21(9): 1873-1886, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37323119

RESUMO

Salicylic acid (SA) is an essential plant hormone that plays critical roles in basal defence and amplification of local immune responses and establishes resistance against various pathogens. However, the comprehensive knowledge of the salicylic acid 5-hydroxylase (S5H) in rice-pathogen interaction is still elusive. Here, we reported that three OsS5H homologues displayed salicylic acid 5-hydroxylase activity, converting SA into 2,5-dihydroxybenzoic acid (2,5-DHBA). OsS5H1, OsS5H2, and OsS5H3 were preferentially expressed in rice leaves at heading stage and responded quickly to exogenous SA treatment. We found that bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo) strongly induced the expression of OsS5H1, OsS5H2, and OsS5H3. Rice plants overexpressing OsS5H1, OsS5H2, and OsS5H3 showed significantly decreased SA contents and increased 2,5-DHBA levels, and were more susceptible to bacterial blight and rice blast. A simple single guide RNA (sgRNA) was designed to create oss5h1oss5h2oss5h3 triple mutants through CRISPR/Cas9-mediated gene mutagenesis. The oss5h1oss5h2oss5h3 exhibited stronger resistance to Xoo than single oss5h mutants. And oss5h1oss5h2oss5h3 plants displayed enhanced rice blast resistance. The conferred pathogen resistance in oss5h1oss5h2oss5h3 was attributed to the significantly upregulation of OsWRKY45 and pathogenesis-related (PR) genes. Besides, flg22-induced reactive oxygen species (ROS) burst was enhanced in oss5h1oss5h2oss5h3. Collectively, our study provides a fast and effective approach to generate rice varieties with broad-spectrum disease resistance through OsS5H gene editing.


Assuntos
Oryza , Xanthomonas , Resistência à Doença/genética , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Mutação/genética , Oryza/metabolismo , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas
6.
Bioinformatics ; 38(11): 3004-3010, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35438146

RESUMO

MOTIVATION: Tissue-level omics data such as transcriptomics and epigenomics are an average across diverse cell types. To extract cell-type-specific (CTS) signals, dozens of cellular deconvolution methods have been proposed to infer cell-type fractions from tissue-level data. However, these methods produce vastly different results under various real data settings. Simulation-based benchmarking studies showed no universally best deconvolution approaches. There have been attempts of ensemble methods, but they only aggregate multiple single-cell references or reference-free deconvolution methods. RESULTS: To achieve a robust estimation of cellular fractions, we proposed EnsDeconv (Ensemble Deconvolution), which adopts CTS robust regression to synthesize the results from 11 single deconvolution methods, 10 reference datasets, 5 marker gene selection procedures, 5 data normalizations and 2 transformations. Unlike most benchmarking studies based on simulations, we compiled four large real datasets of 4937 tissue samples in total with measured cellular fractions and bulk gene expression from different tissues. Comprehensive evaluations demonstrated that EnsDeconv yields more stable, robust and accurate fractions than existing methods. We illustrated that EnsDeconv estimated cellular fractions enable various CTS downstream analyses such as differential fractions associated with clinical variables. We further extended EnsDeconv to analyze bulk DNA methylation data. AVAILABILITY AND IMPLEMENTATION: EnsDeconv is freely available as an R-package from https://github.com/randel/EnsDeconv. The RNA microarray data from the TRAUMA study are available and can be accessed in GEO (GSE36809). The demographic and clinical phenotypes can be shared on reasonable request to the corresponding authors. The RNA-seq data from the EVAPR study cannot be shared publicly due to the privacy of individuals that participated in the clinical research in compliance with the IRB approval at the University of Pittsburgh. The RNA microarray data from the FHS study are available from dbGaP (phs000007.v32.p13). The RNA-seq data from ROS study is downloaded from AD Knowledge Portal. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
RNA , Transcriptoma , Análise de Sequência de RNA , RNA-Seq , Simulação por Computador
7.
Environ Sci Technol ; 57(14): 5988-5998, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36995950

RESUMO

Methylmercury (MeHg) is a potent neurotoxin and has great adverse health impacts on humans. Organisms and sunlight-mediated demethylation are well-known detoxification pathways of MeHg, yet whether abiotic environmental components contribute to MeHg degradation remains poorly known. Here, we report that MeHg can be degraded by trivalent manganese (Mn(III)), a naturally occurring and widespread oxidant. We found that 28 ± 4% MeHg could be degraded by Mn(III) located on synthesized Mn dioxide (MnO2-x) surfaces during the reaction of 0.91 µg·L-1 MeHg and 5 g·L-1 mineral at an initial pH of 6.0 for 12 h in 10 mM NaNO3 at 25 °C. The presence of low-molecular-weight organic acids (e.g., oxalate and citrate) substantially enhances MeHg degradation by MnO2-x via the formation of soluble Mn(III)-ligand complexes, leading to the cleavage of the carbon-Hg bond. MeHg can also be degraded by reactions with Mn(III)-pyrophosphate complexes, with apparent degradation rate constants comparable to those by biotic and photolytic degradation. Thiol ligands (cysteine and glutathione) show negligible effects on MeHg demethylation by Mn(III). This research demonstrates potential roles of Mn(III) in degrading MeHg in natural environments, which may be further explored for remediating heavily polluted soils and engineered systems containing MeHg.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Humanos , Manganês/química , Compostos de Metilmercúrio/metabolismo , Oxidantes/química , Cisteína
8.
BMC Vet Res ; 19(1): 14, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658569

RESUMO

BACKGROUND: Classical swine fever and porcine reproductive and respiratory syndrome have seriously affected the development of the swine breeding industry in China. Vaccine immunization remains the main way to prevent these infections. The aim of this study was to establish an optimized protocol for vaccine immunization against classical swine fever virus (CSFV) and porcine reproductive and respiratory syndrome virus (PRRSV). METHODS: Blood samples were collected from the anterior vena cava of pigs after immunization, and blood indices, secreted levels of specific antibodies and neutralizing antibodies associated with humoral immunity, the proliferation capacity of T lymphocytes as a measure of cellular immunity, and secreted levels of IFN-γ and TNF-α were determined. RESULTS: The results showed that simultaneous immunization against CSFV and PRRSV infections induced strong and specific humoral and T-cellular immune responses, high levels of cytokine IFN-γ secretion and delayed secretion of cytokine TNF-α. Moreover, significantly higher lymphocyte percentages and red blood cell and leukocyte counts were found in the group simultaneously immunized against CSFV and PRRSV. However, no statistically significant differences were observed in hemoglobin values, neutrophil counts, and median cell percentages among the S + PRRS, PRRS-S, and S-PRRS groups. CONCLUSION: This study demonstrated that simultaneous immunization against CSFV and PRRSV had the advantages of inducing a rapid, enhanced, and long-lasting immune response. These findings provide a theoretical basis for the establishment of a reasonable and optimized vaccine immunization protocol against CSFV and PRRSV in combination with a variety of other vaccine inoculations.


Assuntos
Peste Suína Clássica , Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Vacinas Virais , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Peste Suína Clássica/prevenção & controle , Vírus da Febre Suína Clássica , Citocinas , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Doenças dos Suínos/prevenção & controle , Fator de Necrose Tumoral alfa , Vacinação/métodos , Vacinação/veterinária
9.
Allergol Immunopathol (Madr) ; 51(1): 84-91, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36617826

RESUMO

BACKGROUND: Subcutaneous immunotherapy (SCIT) is now the only treatment that can modify the natural course of allergic rhinitis (AR). However, not all children with AR benefit from SCIT. OBJECTIVE: To evaluate the efficacy of SCIT in dust-mites-induced AR children and explore correlative factors predicting treatment response to SCIT. METHODS: 225 children aged 4-17 years old with AR were recruited from January 2016 to September 2019, and monitored at baseline, 4, 12, and 24 months after the start of SCIT treatment. The visual-analogue-score (VAS) was used to assess the clinical symptoms. Multivariate binary logistic regression analyses and receiver operating characteristic curves were used to explore correlative factors in predicting the efficacy of SCIT. RESULTS: The significant declines in VAS started after 4 months of SCIT and continued to improve throughout the study compared with baseline. An increase in children's age (OR=0.688, 95%CI: 0.479-0.988) and those with allergic history (OR=0.097, 95%CI: 0.009-1.095) were negatively associated with the risk of poor efficacy. Polysensitized children were more likely to suffer poor efficacy (OR=15.511 95%CI: 1.319-182.355). The clinical response at month 4 (r=0.707) and month 12 (r=0.925) was related to that at month 24. The area under the curve (AUC) for improvement at month 4 and month 12 was 0.746 and 0.860, respectively. CONCLUSION: Our study confirmed the clinical efficacy of SCIT in AR children. Children with younger age, negative allergic history, and multiple allergens may predict a worse efficacy. The onset of action and the clinical response to SCIT in the second year can be predicted as early as by month 4.


Assuntos
Rinite Alérgica , Animais , Humanos , Criança , Pré-Escolar , Adolescente , Rinite Alérgica/terapia , Pyroglyphidae , Alérgenos/uso terapêutico , Imunoterapia , Resultado do Tratamento , Injeções Subcutâneas , Dessensibilização Imunológica
10.
Molecules ; 28(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687055

RESUMO

The changes in the working environment have necessitated greater requirements in terms of the long-term anti-corrosion ability of metal anti-corrosion coatings, and the emergence of intelligent coatings has met this demand. A nanocontainer with a hydrophobic inner cavity and hydrophilic outer cavity called ß-cyclodextrin (ß-CD) was grafted onto the surface of hydroxyapatite (HAp) with a silane coupling agent, encapsulating benzotriazole (BTA) and embedded in epoxy resin to improve the coating anticorrosion performance. The excellent corrosion resistance of the coating in immersion and scratch experiments was derived from the inert protective layer formed by the reaction of the rapidly released corrosion inhibitor with the corrosion products on the metal surface. After 30 days of immersion experiment, the coating could still maintain the low-frequency impedance value of 6.28 × 107 Ω cm2. In this work, the enhancement of the physical barrier function of HAp nanoparticle and the pH-response function conferred by ß-cyclodextrin provided the coating with good passive and active acting abilities in corrosive environments, respectively.

11.
Molecules ; 28(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677630

RESUMO

The African Swine Fever virus (ASFV) causes an infectious viral disease in pigs of all ages. The development of antiviral drugs primarily aimed at inhibition of proteases required for the proteolysis of viral polyproteins. In this study, the conformation of the pS273R protease in physiological states were investigated, virtually screened the multi-protein conformation of pS273R target proteins, combined various molecular docking scoring functions, and identified five potential drugs from the Food and Drug Administration drug library that may inhibit pS273R. Subsequent validation of the dynamic interactions of pS273R with the five putative inhibitors was achieved using molecular dynamics simulations and binding free energy calculations using the molecular mechanics/Poison-Boltzmann (Generalized Born) (MM/PB(GB)SA) surface area. These findings demonstrate that the arm domain and Thr159-Lys167 loop region of pS273R are significantly more flexible compared to the core structural domain, and the Thr159-Lys167 loop region can serve as a "gatekeeper" in the substrate channel. Leucovorin, Carboprost, Protirelin, Flavin Mononucleotide, and Lovastatin Acid all have Gibbs binding free energies with pS273R that were less than -20 Kcal/mol according to the MM/PBSA analyses. In contrast to pS273R in the free energy landscape, the inhibitor and drug complexes of pS273R showed distinct structural group distributions. These five drugs may be used as potential inhibitors of pS273R and may serve as future drug candidates for treating ASFV.


Assuntos
Vírus da Febre Suína Africana , Antivirais , Inibidores de Proteases , Animais , Vírus da Febre Suína Africana/efeitos dos fármacos , Vírus da Febre Suína Africana/enzimologia , Endopeptidases , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases , Conformação Proteica , Suínos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Antivirais/química , Antivirais/farmacologia
12.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771101

RESUMO

Identification of novel drugs for anti-African swine fever (ASF) applications is of utmost urgency, as it negatively affects pig farming and no effective vaccine or treatment is currently available. African swine fever virus (ASFV) encoded pS273R is a cysteine protease that plays an important role in virus replication. E64, acting as an inhibitor of cysteine protease, has been established as exerting an inhibitory effect on pS273R. In order to obtain a better understanding of the interaction between E64 and pS273R, common docking, restriction docking, and covalent docking were employed to analyze the optimal bonding position between pS273R-E64 and its bonding strength. Additionally, three sets of 100 ns molecular dynamics simulations were conducted to examine the conformational dynamics of pS273R and the dynamic interaction of pS273R-E64, based on a variety of analytical methods including root mean square deviation (RMSD), root mean square fluctuation (RMSF), free energy of ligand (FEL), principal component analysis (PCA), and molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA) analysis. The results show that E64 and pS273R exhibited close binding degrees at the activity center of ASFV pS273R protease. The data of these simulations indicate that binding of E64 to pS273R results in a reduction in flexibility, particularly in the ARM region, and a change in the conformational space of pS273R. Additionally, the ability of E64 to interact with polar amino acids such as ASN158, SER192, and GLN229, as well as charged amino acids such as LYS167 and HIS168, seems to be an important factor in its inhibitory effect. Finally, Octet biostratigraphy confirmed the binding of E64 and pS273R with a KD value of 903 uM. Overall, these findings could potentially be utilized in the development of novel inhibitors of pS273R to address the challenges posed by ASFV.


Assuntos
Vírus da Febre Suína Africana , Cisteína Proteases , Suínos , Animais , Simulação de Dinâmica Molecular , Endopeptidases/metabolismo , Aminoácidos/metabolismo , Cisteína Proteases/metabolismo
13.
Plant Biotechnol J ; 20(5): 876-885, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34890109

RESUMO

Rice blast and bacterial blight represent two of major diseases having devastating impact on the yield of rice in most rice-growing countries. Developments of resistant cultivars are the most economic and effective strategy to control these diseases. Here, we used CRISPR/Cas9-mediated gene editing to rapidly install mutations in three known broad-spectrum blast-resistant genes, Bsr-d1, Pi21 and ERF922, in an indica thermosensitive genic male sterile (TGMS) rice line Longke638S (LK638S). We obtained transgene-free homozygous single or triple mutants in T1 generations. While all single and triple mutants showed increased resistance to rice blast compared with wild type, the erf922 mutants displayed the strongest blast resistance similar with triple mutants. Surprisingly, we found that Pi21 or ERF922 single mutants conferred enhanced resistance to most of tested bacterial blight. Both resistances in mutants were attribute to the up-regulation of SA- and JA-pathway associated genes. Moreover, phenotypic analysis of these single mutants in paddy fields revealed that there were no trade-offs between resistances and main agricultural traits. Together, our study provides a rapid and effective way to generate rice varieties with resistance to both rice blast and bacterial blight.


Assuntos
Resistência à Doença , Oryza , Sistemas CRISPR-Cas/genética , Resistência à Doença/genética , Edição de Genes , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
14.
J Environ Manage ; 311: 114819, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35247759

RESUMO

Cement plants (CPs) are one of the most important anthropogenic sources of mercury (Hg) emissions in China. Over 1000 cement production lines operate in China and use various raw materials; however, little data on Hg emissions is recorded on site. This study investigated a CP in Guizhou Province that uses multiple mining and industrial wastes as part of the circular economy policy. Among the various raw materials, carbide slag had the highest Hg content (2.6 mg/kg) and contributed half of the Hg input. High Hg concentration (27 mg/kg) in the kiln tail dust and a strong Hg enrichment factor (39) was found, which was determined as the ratio of total Hg accumulated within the clinker production process to the daily Hg input from raw materials and fuel. The clinker had negligible Hg (0.001 mg/kg), while the Hg in cement products (0.04 mg/kg) mostly came from additives and retarders. The estimated atmospheric emission factor of Hg from this CP was 161.5 mg Hg/t clinker, which was much higher than those of other CPs in Guizhou that employ low-Hg raw materials. A five-step sequential extraction experiment with kiln tail dust indicates that Hg mainly existed in fraction of F4 (73-96% of the total Hg, possibly as Hg2Cl2) and that some samples had high proportions of water-soluble Hg (up to 21% of the total), which may be easily released into surrounding water bodies and pose high environmental risks. Using low-Hg raw (or alternative raw) materials and conducting proper disposal of kiln tail dust will reduce the environmental risk of Hg from CPs.

15.
Molecules ; 27(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36014318

RESUMO

Artemisia annua is a well-known traditional Chinese medicine. Due to its highest antimalarial efficacy, China has a long history of cultivating A. annua, and it is used for "clearing heat and detoxicating". Several, studies have shown that the A. annua extract exerts cytotoxicity. In order to clarify the basis of the cytotoxic effect of A. annua, 18 sesquiterpenes were isolated from the herb, including 2 new sesquiterpenes and 16 known analogues. The structures of new compounds were elucidated by comprehensive spectroscopic analyses, including HR-ESI-MS, NMR experiments, single-crystal X-ray, and DP4+ and electronic circular dichroism (ECD) calculations. Cytotoxic activity screening revealed three compounds that exhibited cytotoxicity in a dose-dependent manner. Additional exploration showed that compound 5 significantly inhibited the proliferation of CT26 and HCT116 cells and induced apoptosis of HCT116 cells after 24 h. These chemical constituents contributed to elucidating the mechanism of action of the cytotoxic activity of A. annua.


Assuntos
Antimaláricos , Artemisia annua , Artemisia , Sesquiterpenos , Antimaláricos/química , Antimaláricos/farmacologia , Artemisia/química , Artemisia annua/química , China , Sesquiterpenos/química , Sesquiterpenos/farmacologia
16.
Hum Brain Mapp ; 42(7): 2045-2060, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33463862

RESUMO

Transient ischemic attack (TIA), an important risk factor for stroke, is associated with widespread disruptions of functional brain architecture. However, TIA-related structural alterations are not well established. By analyzing structural MRI data from 50 TIA patients versus 40 healthy controls (HCs), here we systematically investigated TIA-related morphological alterations in multiple cortical surface-based indices (cortical thickness [CT], fractal dimension [FD], gyrification index [GI], and sulcal depth [SD]) at multiple levels (local topography, interregional connectivity and whole-brain network topology). For the observed alterations, their associations with clinical risk factors and abilities as diagnostic and prognostic biomarkers were further examined. We found that compared with the HCs, the TIA patients showed widespread morphological alterations and the alterations depended on choices of morphological index and analytical level. Specifically, the patients exhibited: (a) regional CT decreases in the transverse temporal gyrus and lateral sulcus; (b) impaired FD- and GI-based connectivity mainly involving visual, somatomotor and ventral attention networks and interhemispheric connections; and (c) altered GI-based whole-brain network efficiency and decreased FD-based nodal centrality in the middle frontal gyrus. Moreover, the impaired morphological connectivity showed high sensitivities and specificities for distinguishing the patients from HCs. Altogether, these findings demonstrate the emergence of morphological index-dependent and analytical level-specific alterations in TIA, which provide novel insights into neurobiological mechanisms underlying TIA and may serve as potential biomarkers to help diagnosis of the disease. Meanwhile, our findings highlight the necessity of using multiparametric and multilevel approaches for a complete mapping of cerebral morphology in health and disease.


Assuntos
Ataque Isquêmico Transitório/patologia , Rede Nervosa/patologia , Neuroimagem/métodos , Idoso , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem
17.
Planta ; 253(6): 122, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34003383

RESUMO

MAIN CONCLUSION: The rice OsFAH gene functions identically to that of Arabidopsis SSCD1 encoding FAH. Loss of OsFAH causes rice sterility. Fumarylacetoacetate hydrolase (FAH) is the last enzyme in the tyrosine (Tyr) degradation pathway that is crucial for animals. By genetic analysis of the mutant of Short-day Sensitive Cell Death 1 gene encoding Arabidopsis FAH, we first found the pathway also plays a critical role in plants (Han et al., Plant Physiol 162:1956-1964, 2013). To further understand the role of the Tyr degradation pathway in plants, we investigated a biological function of the rice FAH. Firstly, the cDNA of rice FAH gene (OsFAH) was cloned and confirmed to be able to rescue the Arabidopsis Short-day Sensitive Cell Death 1 mutant defective in the FAH. Then, we identified the OsFAH T-DNA insertion mutant and generated the OsFAH RNA interference lines, and found that loss of OsFAH results in rice sterility. Furthermore, we analyzed expression of the OsFAH gene in roots, stems, leaves and young panicles at booting stage of rice and found that its transcript level was highest in young panicles and lowest in roots. In addition, the expression analysis of ß-glucuronidase driven by OsFAH promoter in transgenic Arabidopsis showed that the OsFAH promoter was highly active in aerial tissues in vegetative stage, and sepals, filaments and stigma in reproductive stage. These results suggested that FAH plays an important role in rice fertility.


Assuntos
Arabidopsis , Oryza , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Fertilidade , Regulação da Expressão Gênica de Plantas , Hidrolases/genética , Hidrolases/metabolismo , Oryza/genética , Oryza/metabolismo , Plantas Geneticamente Modificadas/metabolismo
18.
Int Arch Allergy Immunol ; 182(12): 1231-1244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34280916

RESUMO

BACKGROUND: The role of salivary-specific IgG4 and IgA in subcutaneous immunotherapy (SCIT) is not well defined. We aimed to investigate the change of IgG4 and IgA in both serum and saliva and their correlations with IgE-blocking-factor (IgE-BF) during SCIT. METHOD: 307 Dermatophagoides pteronyssinus (DP) allergic rhinitis and/or asthma patients were recruited for this study. 286 patients received DP-SCIT for 1 year. Twenty-one patients received only symptomatic treatment. DP-, Der p 1-, and Der p 2-specific IgE in serum, specific-IgG4 and Der p 2-specific IgA1 and IgA2 in both serum and saliva were measured at timepoints 0, 4, and 12 months during DP-SCIT. Correlation between salivary and serological IgG4, IgA, and their correlation with DP-specific IgE-BF measured in serum was evaluated. RESULTS: During DP-SCIT, the allergen-specific IgG4 in both saliva and serum increased and correlated significantly, the correlation becomes stronger over the treatment time. DP-specific IgE-BF significantly correlated with DP-specific IgG4 in serum (p < 0.0001) at different timepoints and in saliva at 12 months of SCIT (p < 0.01). No change in Der p 2-specific IgA during DP-SCIT was observed, and the IgA in serum did not correlate with IgA in saliva. There was no correlation between DP IgE-BF and Der p 2-specific IgA in serum or saliva. The control group did not exhibit significant changes in any antibody level measured. CONCLUSION: The IgE blocking activity induced by DP-SCIT treatment correlated with specific IgG4 and not IgA. The IgG4 in saliva correlates with serum IgG4 and can be an alternative immunological marker beyond 1 year of SCIT treatment.


Assuntos
Alérgenos/imunologia , Antígenos de Dermatophagoides/imunologia , Asma/terapia , Dermatophagoides pteronyssinus/imunologia , Dessensibilização Imunológica , Isotipos de Imunoglobulinas/metabolismo , Rinite Alérgica Perene/terapia , Adolescente , Adulto , Animais , Asma/imunologia , Asma/metabolismo , Biomarcadores/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Isotipos de Imunoglobulinas/imunologia , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Rinite Alérgica Perene/imunologia , Rinite Alérgica Perene/metabolismo , Saliva/imunologia , Saliva/metabolismo , Resultado do Tratamento , Adulto Jovem
19.
Environ Sci Technol ; 55(18): 12493-12503, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34468125

RESUMO

Monomethylmercury (MMHg) exposure can induce adverse neurodevelopmental effects in humans and is a global environmental health concern. Human exposure to MMHg occurs predominately through the consumption of fishery foods and rice in Asia, but it is challenging to quantify these two exposure sources. Here, we innovatively utilized MMHg compound-specific stable isotope analyses (MMHg-CSIA) of the hair to quantify the human MMHg sources in coastal and inland areas, where fishery foods and rice are routinely consumed. Our data showed that the fishery foods and rice end members had distinct Δ199HgMMHg values in both coastal and inland areas. The Δ199HgMMHg values of the human hair were comparable to those of fishery foods but not those of rice. Positive shifts in the δ202HgMMHg values of the hair from diet were observed in the study areas. Additionally, significant differences in δ202Hg versus Δ199Hg were detected between MMHg and inorganic Hg (IHg) in the human hair but not in fishery foods and rice. A binary mixing model was developed to estimate the human MMHg exposures from fishery foods and rice using Δ199HgMMHg data. The model results suggested that human MMHg exposures were dominated (>80%) by fishery food consumption and were less affected by rice consumption in both the coastal and inland areas. This study demonstrated that the MMHg-CSIA method can provide unique information for tracking human MMHg exposure sources by excluding the deviations from dietary surveys, individual MMHg absorption/demethylation efficiencies, and the confounding effects of IHg.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Oryza , Monitoramento Ambiental , Cabelo/química , Humanos , Isótopos , Mercúrio/análise
20.
Bioorg Med Chem ; 35: 116055, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33607487

RESUMO

African swine fever (ASF) is a viral disease in swine that results in high mortality in domestic pigs and causes considerable economic losses. Currently, there is no effective vaccine or drugs available for treatment. Identification of new anti-ASFV drugs is urgently needed. Here, the pS273R protein of the African swine fever virus (ASFV) is a specific SUMO-1-like cysteine protease that plays an important role in its replication process. To inhibit virus replication and improve treatment options, a set of small-molecule compounds, targeted inhibitors against the ASFV pS273R protease, were obtained through molecular screening by homology modeling and molecular docking based on structural information of pS273R. Our results clearly demonstrated that the 14th carbon atom of the cysteinase inhibitor E-64 could form one CS covalent bond with the Cys 232 amino acid of the pS273R protease and seven additional hydrogen bonds to maintain a stable binding state. Simultaneously, cell viability, immunophenotyping, and in vitro enzyme activity inhibition assays were performed to comprehensively evaluate E-64 characteristics. Our findings demonstrated that 4 mmol/L E-64 could effectively inhibit the enzyme activity center of the pS273R protease by preventing pS273R protease from lysing pp62, while promoting the upregulation of immune-related cytokines at the transcription level. Moreover, cell viability results revealed that 4 mmol/L E-64 was not cytotoxic. Taken together, we identified a novel strategy to potentially prevent ASFV infection in pigs by blocking the activity of pS273R protease with a small-molecule inhibitor.


Assuntos
Vírus da Febre Suína Africana/enzimologia , Cisteína Proteases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas Virais/antagonistas & inibidores , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Cisteína Proteinase/química , Relação Dose-Resposta a Droga , Modelos Moleculares , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Suínos , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
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