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1.
Toxicol Appl Pharmacol ; 469: 116529, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37100089

RESUMO

The most commonly reported side effect of azithromycin is gastrointestinal (GI) disorders, and the main acid degradation product is 3'-Decladinosyl azithromycin (impurity J). We aimed to compare the GI toxicity of azithromycin and impurity J on zebrafish larvae and investigate the mechanism causing the differential GI toxicity. Results of our study showed that the GI toxicity induced by impurity J was higher than that of azithromycin in zebrafish larvae, and the effects of impurity J on transcription in the digestive system of zebrafish larvae were significantly stronger than those of azithromycin. Additionally, impurity J exerts stronger cytotoxic effects on GES-1 cells than azithromycin. Simultaneously, impurity J significantly increased ghsrb levels in the zebrafish intestinal tract and ghsr levels in human GES-1 cells compared to azithromycin, and ghsr overexpression significantly reduced cell viability, indicating that GI toxicity induced by azithromycin and impurity J may be correlated with ghsr overexpression induced by the two compounds. Meanwhile, molecular docking analysis showed that the highest -CDOCKER interaction energy scores with the zebrafish GHSRb or human GHSR protein might reflect the effect of azithromycin and impurity J on the expression of zebrafish ghsrb or human ghsr. Thus, our results suggest that impurity J has higher GI toxicity than azithromycin due to its greater ability to elevate ghsrb expression in zebrafish intestinal tract.


Assuntos
Azitromicina , Peixe-Zebra , Animais , Humanos , Azitromicina/toxicidade , Larva , Simulação de Acoplamento Molecular , Intestinos
2.
BMC Plant Biol ; 19(1): 140, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987586

RESUMO

BACKGROUND: Miniature inverted-repeat transposable elements (MITEs) and long terminal repeat (LTR) retrotransposons are ubiquitous in plants genomes, and highly important in their evolution and diversity. However, their mechanisms of insertion/amplification and roles in Citrus genome's evolution/diversity are still poorly understood. RESULTS: To address this knowledge gap, we developed different computational pipelines to analyze, annotate and classify MITEs and LTR retrotransposons in six different sequenced Citrus species. We identified 62,010 full-length MITEs from 110 distinguished families. We observed MITEs tend to insert in gene related regions and enriched in promoters. We found that DTM63 is possibly an active Mutator-like MITE family in the traceable past and may still be active in Citrus. The insertion of MITEs resulted in massive polymorphisms and played an important role in Citrus genome diversity and gene structure variations. In addition, 6630 complete LTR retrotransposons and 13,371 solo-LTRs were identified. Among them, 12 LTR lineages separated before the differentiation of mono- and dicotyledonous plants. We observed insertion and deletion of LTR retrotransposons was accomplished with a dynamic balance, and their half-life in Citrus was ~ 1.8 million years. CONCLUSIONS: These findings provide insights into MITEs and LTR retrotransposons and their roles in genome diversity in different Citrus genomes.


Assuntos
Citrus/genética , Elementos de DNA Transponíveis/genética , Genoma de Planta/genética , Sequências Repetidas Invertidas/genética , Retroelementos/genética , Sequências Repetidas Terminais/genética , Variação Genética
3.
Plant J ; 92(2): 263-275, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28749585

RESUMO

In plant, a few 22-nt miRNAs direct cleavages of their targets and trigger the biogenesis of phased small interfering RNAs (phasiRNAs) in plant. In this study, we characterized a miRNA triggering phasiRNAs generation, miR3954, and explored its downstream target genes and potential function. Our results demonstrated that miR3954 showed specific expression in the flowers of citrus species, and it targeted a NAC transcription factor (Cs7 g22460) and two non-coding RNA transcripts (lncRNAs, Cs1 g09600 and Cs1 g09635). The production of phasiRNAs was detected from transcripts targeted by miR3954, and was further verified in both sequencing data and transient expression experiments. PhasiRNAs derived from the two lncRNAs targeted not only miR3954-targeted NAC gene but also additional NAC homologous genes. No homologous genes of these two lncRNAs were found in plants other than citrus species, implying that this miR3954-lncRNAs-phasiRNAs-NAC pathway is likely citrus-specific. Transgenic analysis indicated that the miR3954-overexpressing lines showed decreased transcripts of lncRNA, elevated abundance of phasiRNAs and reduced expression of NAC genes. Interestingly, the overexpression of miR3954 leads to early flowering in citrus plants. In summary, our results illustrated a model of the regulatory network of miR3954-lncRNA-phasiRNAs-NAC, which may be functionally involved in flowering in citrus.


Assuntos
Citrus sinensis/fisiologia , Flores/crescimento & desenvolvimento , MicroRNAs/fisiologia , RNA Interferente Pequeno/fisiologia , Citrus sinensis/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Fatores de Tempo
4.
J Environ Manage ; 208: 15-23, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29245145

RESUMO

The leaching behavior of six typical toxic metals (Pb, Zn, Cr, Cd, Cu and Ni) from raw and chemically stabilized (phosphate and chelating agent) municipal solid waste incineration (MSWI) fly ash were investigated using citric acid. Leaching tests indicated that phosphate stabilization can effectively decrease the leaching of Zn, Cd and Cr; whereas chelating agent stabilization shows a strong ability to lower the release of Pb, Cd and Cu, but instead increases the solubility of Zn and Cr at low pH conditions. Sequential extraction results suggested that the leaching of Pb, Zn and Cd in both the stabilized MSWI fly ash samples led to the decrease in Fe/Mn oxide fraction and the increase in exchangeable and carbonate fractions. The leaching of Cr was due to the decrease in exchangeable, carbonate and Fe/Mn oxide fractions in phosphate-stabilized and chelating agent-stabilized MSWI fly ash. The leaching of Cu in both stabilized MSWI fly ash was greatly ascribed to the decrease in Fe/Mn oxide and oxidisable fractions. Moreover, predicted curves by geochemical model indicated that both stabilized MSWI fly ash have the risk of releasing toxic metals under strong acid environment.


Assuntos
Ácido Cítrico , Cinza de Carvão , Metais Pesados , Resíduos Sólidos , Carbono , Incineração , Material Particulado , Eliminação de Resíduos
5.
BMC Genomics ; 16: 995, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26597278

RESUMO

BACKGROUND: With the availability of rapidly increasing number of genome and transcriptome sequences, lineage-specific genes (LSGs) can be identified and characterized. Like other conserved functional genes, LSGs play important roles in biological evolution and functions. RESULTS: Two set of citrus LSGs, 296 citrus-specific genes (CSGs) and 1039 orphan genes specific to sweet orange, were identified by comparative analysis between the sweet orange genome sequences and 41 genomes and 273 transcriptomes. With the two sets of genes, gene structure and gene expression pattern were investigated. On average, both the CSGs and orphan genes have fewer exons, shorter gene length and higher GC content when compared with those evolutionarily conserved genes (ECs). Expression profiling indicated that most of the LSGs expressed in various tissues of sweet orange and some of them exhibited distinct temporal and spatial expression patterns. Particularly, the orphan genes were preferentially expressed in callus, which is an important pluripotent tissue of citrus. Besides, part of the CSGs and orphan genes expressed responsive to abiotic stress, indicating their potential functions during interaction with environment. CONCLUSION: This study identified and characterized two sets of LSGs in citrus, dissected their sequence features and expression patterns, and provided valuable clues for future functional analysis of the LSGs in sweet orange.


Assuntos
Linhagem da Célula , Citrus sinensis/fisiologia , Proteínas de Plantas/genética , Composição de Bases , Citrus sinensis/classificação , Citrus sinensis/genética , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estruturas Genéticas , Genoma de Planta
6.
Pharmacoepidemiol Drug Saf ; 24(9): 962-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26095121

RESUMO

PURPOSE: Statistical shrinkage is a potential statistical method to improve the accuracy of signal detection results and avoid spurious associations detected by disproportionality analyses. In this study, we introduced statistical shrinkage influence on disproportionality methods in spontaneous reporting system in China. METHODS: We added the shrinkage parameters in the numerator and denominator, denoted as in the formula of disproportionality analysis. The shrinkage parameters were subjectively set to between 0 and 5, with an interval of 0.1. Adverse drug reaction product label database was deemed as a proxy of golden standard to evaluate the effect of statistical shrinkage. Reports in the years of 2010-2011 were extracted from the national spontaneous reporting system database as the data source for analysis in this study. RESULTS: When α was around 0.5, the Youden index reached the maximum for each disproportionality methods in this study. The value of 0.6 was suggested as the most appropriate statistical shrinkage parameter for reporting odds ratio and proportional reporting ratio and 0.2 for information component based on the spontaneous reporting system of China.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Farmacovigilância , Algoritmos , China/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Razão de Chances
7.
Environ Sci Pollut Res Int ; 30(16): 47873-47881, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36749520

RESUMO

ß-N-methylamino-L-alanine (BMAA), which has been considered as an environmental factor that caused amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) or Alzheimer's disease, could be produced by a variety of genera cyanobacteria. BMAA is widely present in water sources contaminated by cyanobacteria and may threaten human health through drinking water. Although oxidants commonly used in drinking water plants such as chlorine, ozone, hydrogen peroxide, and hydroxyl radicals have been shown to effectively degrade BMAA, there are limited studies on the mechanism of BMAA degradation by different oxidants, especially ozone. This work systematically explored the effectiveness of BMAA ozonation degradation, investigated the effect of the operating parameters on the effectiveness of degradation, and speculated on the pathways of BMAA decomposition. The results showed that BMAA could be quickly eliminated by ozone, and the removal rates of BMAA were nearly 100% in pure water, but the removal rates were reduced in actual water. BMAA was primarily degraded by direct oxidation of ozone molecules in acidic and near-neutral conditions, and indirect oxidation of •OH accounted for the main part under strong alkaline conditions. The pH value had a significant effect on the decomposition of BMAA, and the degradation rate of BMAA was fastest at near-neutral pH value. The degradation rates of TOC were significantly lower than that of BMAA, indicating that by-products were generated during the degradation process. Three by-products ([M-H]+ = 105, 90, and 88) were identified by UPLC-MS/MS, and the degradation pathways of BMAA were proposed. The production of by-products was attributed to the fracture of the C-N bonds. This work is helpful for the in-depth understanding on the mechanism and demonstration of the feasibility of the oxidation of BMAA by the ozone process. HIGHLIGHTS: • The reaction of ozonation BMAA was easy to occur. • The degradation rate was fast under near-neutral conditions. • Direct oxidation under neural conditions was the main pathway for ozone degradation of BMAA. • Three products were detected, and the reaction path was inferred.


Assuntos
Diamino Aminoácidos , Água Potável , Ozônio , Humanos , Neurotoxinas , Cromatografia Líquida , Espectrometria de Massas em Tandem , Toxinas de Cianobactérias , Diamino Aminoácidos/química , Oxidantes
8.
Expert Opin Drug Saf ; 19(3): 339-347, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31914329

RESUMO

Objectives: Limited evidence has suggested that cefoperazone-sulbactam causes coagulation disorders and bleeding.Methods: The authors conducted a retrospective study to compare patients receiving cefoperazone-sulbactam versus those treated with cefoperazone-tazobactam or ceftazidime. Propensity-score matching was used to explore whether treatment with cefoperazone-sulbactam increased the risk of prothrombin time (PT) prolongation, coagulation disorders, and bleeding, or decreased platelets (PLT).Results: The cohort included 23,242 patients. Among patients receiving cefoperazone-sulbactam, the risk of PT prolongation, coagulation disorders, decreased PLT, and bleeding was 5.3%, 9.2%, 15.7%, and 4.2%, respectively. Propensity-score matching analyses suggested that cefoperazone-sulbactam increased the risk of PT prolongation (aOR 2.26, 95% CI 1.61-3.18), coagulation disorders (aOR 1.81, 95% CI 1.43-2.30), and decreased PLT (aOR 1.46, 95% CI 1.25-1.72), but not increase bleeding (aOR 1.05, 95% CI 0.79-1.40) compared with ceftazidime. Patients receiving cefoperazone-sulbactam had higher risk of PT prolongation (aOR 1.53, 95% CI 1.11-2.10), coagulation disorders (aOR 1.53, 95% CI 1.21-1.95), but not decreased PLT (aOR 0.93, 95% CI 0.81-1.07) or bleeding (aOR 1.11, 95% CI 0.87-1.42), compared with those receiving cefoperazone-tazobactam.Conclusion: Cefoperazone-sulbactam may be associated with a higher risk of PT prolongation and coagulation disorders compared with cefoperazone-tazobactam and ceftazidime.


Assuntos
Transtornos da Coagulação Sanguínea/induzido quimicamente , Cefoperazona/efeitos adversos , Hemorragia/induzido quimicamente , Sulbactam/efeitos adversos , Adolescente , Adulto , Idoso , Antibacterianos/efeitos adversos , Plaquetas/efeitos dos fármacos , Ceftazidima/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Protrombina/estatística & dados numéricos , Tazobactam/efeitos adversos , Adulto Jovem
9.
Drug Saf ; 40(4): 343-350, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28074424

RESUMO

INTRODUCTION: The method of time-to-onset (TTO) has been proposed to overcome the drawbacks of traditional disproportionality analyses (DPAs), and it has been used for detecting safety signals of vaccines and some non-vaccine products in spontaneous reporting systems (SRSs). However, there is no consensus on its superiority over DPAs. Further, it is still not clear whether this novel approach can be generalized to the entire national SRS database. OBJECTIVE: The purpose of this study was to generalize the TTO method to the Chinese SRS and to identify suitable parameters for its optimal performance. METHODS: Reports submitted to the national SRS of China in 2014 were used as the data source for analysis. We evaluated the performance of TTO by using product labels as proxies for the gold standard. A series of values of significance level and time windows were explored to identify the most suitable parameters for TTO based on Youden's index, a statistic that summarizes the performance of a diagnostic test. Additionally, we compared TTO with traditional DPAs and explored the characteristics of signals detected by these methods. RESULTS: Compared with DPAs, TTO had a lower sensitivity, but higher specificity and positive predictive value. At a significance level of 0.2 and no restrictions on time windows, TTO had the highest Youden's index. The kappa coefficients between TTO and DPAs were rather low, indicating poor agreement between the two methods. More than 30% of the true signals detected by TTO were not identified by DPAs. Furthermore, TTO needed more number of reports to be able to detect signals. CONCLUSIONS: TTO can detect signals missed by traditional DPAs and could be an important complementary tool to the currently used DPAs in the SRS of China. We recommend a significance level of 0.2 and no restrictions on time windows for TTO.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Algoritmos , Vacinas/efeitos adversos , China , Bases de Dados Factuais/estatística & dados numéricos , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Vacinas/administração & dosagem
10.
Nat Genet ; 49(5): 765-772, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28394353

RESUMO

The emergence of apomixis-the transition from sexual to asexual reproduction-is a prominent feature of modern citrus. Here we de novo sequenced and comprehensively studied the genomes of four representative citrus species. Additionally, we sequenced 100 accessions of primitive, wild and cultivated citrus. Comparative population analysis suggested that genomic regions harboring energy- and reproduction-associated genes are probably under selection in cultivated citrus. We also narrowed the genetic locus responsible for citrus polyembryony, a form of apomixis, to an 80-kb region containing 11 candidate genes. One of these, CitRWP, is expressed at higher levels in ovules of polyembryonic cultivars. We found a miniature inverted-repeat transposable element insertion in the promoter region of CitRWP that cosegregated with polyembryony. This study provides new insights into citrus apomixis and constitutes a promising resource for the mining of agriculturally important genes.


Assuntos
Citrus/genética , Genoma de Planta/genética , Genômica/métodos , Análise de Sequência de DNA/métodos , Apomixia/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Citrus/classificação , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Variação Genética , Filogenia , Polimorfismo de Nucleotídeo Único , Reprodução Assexuada/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
11.
Drug Saf ; 39(11): 1043-1051, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27550440

RESUMO

It has been more than 25 years since an adverse drug reaction (ADR) monitoring agency was first established in China. In the past few years, the National ADR Monitoring System (NADRMS) has developed rapidly in the country. However, this system has not been reviewed in detail in the literature. Our aim was to demonstrate how individual case safety reports (ICSRs) are reported and evaluated and how data quality control is achieved in China. We also aimed to discuss the present status and future of NADRMS. We reviewed the relevant regulations and literature around ADR reporting in China. ADR report collection tools in China have gone through three phases, namely paper-based reporting, software-based reporting using standalone computers, and online reporting. Nowadays the online reporting system plays an important role in China and the number of ADR reports has rapidly increased. NADRMS is similar to most of the ADR reporting systems around the world, but also has its own unique characteristics such as four levels of monitoring agencies. In summary, there is still a long way to go for China to establish a high-level ADR monitoring system to ensure drug safety.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/organização & administração , Sistemas de Notificação de Reações Adversas a Medicamentos/legislação & jurisprudência , China , Humanos
12.
Materials (Basel) ; 9(10)2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28773916

RESUMO

Nanomaterials, such as Graphene, h-BN nanoparticles and MoS2 nanotubes, have shown their ability in improving the tribological performance of amorphous carbon (a-C) coatings. In the current study, the effectiveness of ZrO2 nanoparticles (ZrO2-NPs) in lubricating the self-mated nonhydrogenated a-C contacts was investigated in boundary lubrication regime. The results showed that 13% less friction and 50% less wear compared to the base oil were achieved by employing ZrO2-NPs in the base oil in self-mated a-C contacts. Via analyzing the ZrO2-NPs and the worn a-C surface after tests, it was found that the improved lubrication by ZrO2-NPs was based on "polishing effects", which is a new phenomenon observed between a-C and nanoparticles. Under the "polishing effect", micro-plateaus with extremely smooth surface and uniform height were produced on the analyzed a-C surface. The resulting topography of the a-C coating is suitable for ZrO2-NPs to act as nano-bearings between rubbing surfaces. Especially, the ZrO2-NPs exhibited excellent mechanical and chemical stability, even under the severe service condition, suggesting that the combination of nonhydrogenated a-C coating with ZrO2-NPs is an effective, long lasting and environment-friendly lubrication solution.

13.
Expert Opin Drug Saf ; 13(7): 853-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24918197

RESUMO

OBJECTIVE: Several disproportionality analysis methods are widely used for signal detection. The goal of this study was to compare the concordance of the performance characteristics of these methods in spontaneous reporting system of China. METHODS: Algorithms including reporting odds ratio (ROR), proportional reporting ratio (PRR) and information component (IC), a composite criterion previously used by Medicines and Healthcare Products Regulatory Agency (MHRA) were compared. Kappa coefficient was used as the gauge to test the concordance. Reports received in the year 2004 and 2005 were extracted for analysis in this study. RESULTS: After data processing, 361,872 reports representing 52,769 combinations were analysed. The analysis generated 24,022, 22,646, 5637 and 5302 signals of disproportionality by PRR, ROR, MHRA and IC, respectively. The kappa coefficient increased with the threshold of number of drug-adverse drug reactions (ADR) combination, and the coefficient exceeded 0.7 when the number of suspected drug-ADR exceeded 2. CONCLUSION: This study shows that different measures used are broadly comparable in spontaneous reporting system in China when two or more cases per combination have been collected.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Algoritmos , China , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Razão de Chances
14.
Eur J Biochem ; 271(18): 3715-28, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15355349

RESUMO

The tissue-specific transcription factors HNF1alpha and HNF1beta are closely related homeodomain proteins conserved in vertebrate evolution. Heterozygous mutations in human HNF1beta but not in HNF1alpha genes are associated with kidney malformations. Overexpression of HNF1beta in Xenopus embryos leads to defective pronephros development, while HNF1alpha has no effect. We have defined the regions responsible for this functional difference between HNF1beta and HNF1alpha in transfected HeLa cells as well as in injected Xenopus embryos. Using domain swapping experiments, we located a nuclear localization signal in the POUH domain of HNF1beta, and showed that the POUS and POUH domains of HNF1beta mediate a high transactivation potential in transfected cells. In injected Xenopus embryos three HNF1beta domains are involved in nephrogenesis. These include the dimerization domain, the 26 amino acid segment specific for splice variant A as well as the POUH domain. As HNF1beta together with Pax8 and lim1 constitute the earliest regulators in the pronephric anlage, it is possible that they cooperate during early nephrogenesis. We have shown here that HNF1beta can overcome the enlargement and the induction of an ectopic pronephros mediated by overexpression of Pax8 and lim1. However, the phenotype induced by Pax8 and lim1 overexpression and characterized by cyst-like structures and thickening of the pronephric tubules was not altered by HNF1beta overexpression. Taken together, HNF1beta acts antagonistically to Pax8 and lim1 in only some processes during nephrogenesis, and a simple antagonistic relationship does not completely describe the functions of these genes. We conclude that HNF1beta has some distinct morphogenetic properties during nephrogenesis.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Nefropatias/prevenção & controle , Rim/embriologia , Proteínas Nucleares , Transativadores/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência Conservada , Dimerização , Células HeLa , Fator 1-beta Nuclear de Hepatócito , Humanos , Imuno-Histoquímica , Microinjeções , Dados de Sequência Molecular , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Ativação Transcricional , Proteínas de Xenopus , Xenopus laevis/embriologia
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