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1.
J Nanobiotechnology ; 22(1): 222, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38698420

RESUMO

BACKGROUND: Aging is a very complex physiological phenomenon, and sEVs are involved in the regulation of this mechanism. Serum samples from healthy individuals under 30 and over 60 years of age were collected to analyze differences in sEVs proteomics. RESULTS: Based on PBA analysis, we found that sEVs from the serum of elderly individuals highly express TACSTD2 and identified a subpopulation marked by TACSTD2. Using ELISA, we verified the upregulation of TACSTD2 in serum from elderly human and aged mouse. In addition, we discovered that TACSTD2 was significantly increased in samples from tumor patients and had better diagnostic value than CEA. Specifically, 9 of the 13 tumor groups exhibited elevated TACSTD2, particularly for cervical cancer, colon cancer, esophageal carcinoma, liver cancer and thyroid carcinoma. Moreover, we found that serum sEVs from the elderly (especially those with high TACSTD2 levels) promoted tumor cell (SW480, HuCCT1 and HeLa) proliferation and migration. CONCLUSION: TACSTD2 was upregulated in the serum of elderly individuals and patients with tumors, and could serve as a dual biomarker for aging and tumors.


Assuntos
Antígenos de Neoplasias , Biomarcadores Tumorais , Moléculas de Adesão Celular , Neoplasias , Humanos , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/genética , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Animais , Camundongos , Feminino , Idoso , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/genética , Neoplasias/metabolismo , Masculino , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Adulto , Proliferação de Células , Movimento Celular , Envelhecimento/genética , Proteômica/métodos , Células HeLa , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Regulação para Cima
2.
Am J Physiol Cell Physiol ; 325(3): C623-C632, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37458439

RESUMO

Ectopic pregnancy is an acute abdominalgia in obstetrics and gynecology, especially in fallopian tubal pregnancy. The ion channel protein transmembrane protein 16A (TMEM16A) is widely distributed in various tissues, even in the oviduct. In this study, we showed that TMEM16A was expressed in the human fallopian tube and was upregulated in patients with tubal pregnancy. By measuring isolated fallopian tube tissues, we found that TMEM16A was involved in regulating not only the contraction of muscle strips but also the beat frequency of cilia. In addition, pharmacological activation or inhibition of TMEM16A could lead to retention of embryos in oviducts. Moreover, the embryos in oviducts were delayed in development and some of them had malformations and deletions. The total number of embryos in the oviducts and uterus was significantly less than that of the control group. Furthermore, we detected changes in the level of m6A methylation, where the relevant writers and readers were reduced in tubal tissues from tubal pregnancies. In m6A mRNA methylation, writers catalyze the addition of methyl groups to cytosine residues and readers bind to the methyl groups and affect gene translation. In human fallopian tube epithelial cell line FTE187, we found that interference with methyltransferase 3 (METTL3) expression increased TMEM16A, suggesting that TMEM16A might be regulated by m6A methylation. In general, our study revealed a novel regulatory point for embryo transport and development, introducing a new role for the diagnosis and treatment of tubal pregnancy.NEW & NOTEWORTHY The ion channel protein TMEM16A is expressed in the epithelium and smooth muscle of the human fallopian tube and is upregulated in patients with tubal pregnancy. TMEM16A is involved in regulating the smooth muscle contraction and the cilia beating. Dysregulated TMEM16A may result in embryo retention in the oviduct and delayed early embryo development. Our study reveals a new regulatory point for embryo transport and development.


Assuntos
Tubas Uterinas , Gravidez Tubária , Gravidez , Feminino , Animais , Humanos , Tubas Uterinas/metabolismo , Oviductos/metabolismo , Gravidez Tubária/metabolismo , Músculo Liso/metabolismo , Canais Iônicos/metabolismo , Metiltransferases
3.
Clin Chem Lab Med ; 59(5): 883-891, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33554565

RESUMO

OBJECTIVES: Autoverification systems have greatly improved laboratory efficiency. However, the long-developed rule-based autoverfication models have limitations. The machine learning (ML) algorithm possesses unique advantages in the evaluation of large datasets. We investigated the utility of ML algorithms for developing an artificial intelligence (AI) autoverification system to support laboratory testing. The accuracy and efficiency of the algorithm model were also validated. METHODS: Testing data, including 52 testing items with demographic information, were extracted from the laboratory information system and Roche Cobas® IT 3000 from June 1, 2018 to August 30, 2019. Two rounds of modeling were conducted to train different ML algorithms and test their abilities to distinguish invalid reports. Algorithms with the top three best performances were selected to form the finalized ensemble model. Double-blind testing between experienced laboratory personnel and the AI autoverification system was conducted, and the passing rate and false-negative rate (FNR) were documented. The working efficiency and workload reduction were also analyzed. RESULTS: The final AI system showed a 89.60% passing rate and 0.95 per mille FNR, in double-blind testing. The AI system lowered the number of invalid reports by approximately 80% compared to those evaluated by a rule-based engine, and therefore enhanced the working efficiency and reduced the workload in the biochemistry laboratory. CONCLUSIONS: We confirmed the feasibility of the ML algorithm for autoverification with high accuracy and efficiency.


Assuntos
Sistemas de Informação em Laboratório Clínico , Serviços de Laboratório Clínico , Algoritmos , Inteligência Artificial , Humanos , Laboratórios , Aprendizado de Máquina
4.
Neurogenetics ; 21(1): 39-49, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31720972

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic disease leading to stroke and vascular dementia. CADASIL is an inherited small blood vessel disease caused by mutations in the gene encoding the neurogenic locus notch homolog protein 3 (NOTCH3). NOTCH3 is large type I membrane receptor mainly expressed in vascular smooth muscle cells and pericytes. Most identified mutations result in insert or deletion of a cysteine residue within the EGF-like repeats. To date, some cases with a cysteine-sparing mutant have been described. Genetic analysis revealed a novel mutation in NOTCH3 in a CADASIL family. Molecular analysis revealed its potential pathogenic mechanism in causing CADASIL. In this paper, we present a Chinese family with a novel cysteine-sparing mutation in exon 3 (c.218G>C, p.G73A) of the NOTCH3 gene. Family carriers of the same mutation presented with symptoms and imaging abnormalities characteristic of CADASIL. The location of glycine 73 in between C5-C6 disulfide bond of EGF-like domain 1 shows high conservation from humans to zebra fish. It has previously been suggested that the aggregate-prone property of mutant NOTCH3 contributes to a cytotoxic effect in the pathogenic mechanism underlying CADASIL. Here, we investigated the pathogenic mechanism of the new mutation in vitro using HEK293 cells transfected with either a wild-type (WT) or c.218G>C (p.G73A) NOTCH3ECD plasmids, and we found p.G73A NOTCH3ECD was more prone to form aggregation and resistant to degradation. Moreover, the p.G73A NOTCH3ECD compromised cell viability by promoting apoptosis. Two known CADASIL mutants R133C and R75P showed similar results with G73A mutants. Our study here identified G73A as a new mutation in NOTCH3 to cause CADASIL and revealed that the G73A mutation and two known mutants R75P and R133C decreased NOTCH3 protein turnover and induced cell death.


Assuntos
CADASIL/genética , Receptor Notch3/genética , Povo Asiático/genética , CADASIL/patologia , Sobrevivência Celular/genética , China , Cisteína/genética , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Agregação Patológica de Proteínas/genética , Receptor Notch3/metabolismo
5.
Plant Cell Physiol ; 61(2): 370-380, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31670803

RESUMO

Pentatricopeptide repeat (PPR) proteins are helical repeat RNA-binding proteins that function in RNA processing by conferring sequence-specific RNA-binding activity. Owing to the lethality of PPR mutants, functions of many PPR proteins remain obscure. In this study, we report the function of PPR20 in intron splicing in mitochondria and its role in maize seed development. PPR20 is a P-type PPR protein targeted to mitochondria. The ppr20 mutants display slow embryo and endosperm development. Null mutation of PPR20 severely reduces the cis-splicing of mitochondrial nad2 intron 3, resulting in reduction in the assembly and activity of mitochondrial complex I. The ppr20-35 allele with a Mu insertion in the N-terminal region shows a much weaker phenotype. Molecular analyses revealed that the mutant produces a truncated transcript, coding for PPR20ΔN120 lacking the N-terminal 120 amino acids. Subcellular localization revealed that PPR20ΔN120:GFP is able to target to mitochondria as well, suggesting the sequence diversity of the mitochondrial targeting peptides. Another mutant zm_mterf15 was also found to be impaired in the splicing of mitochondrial nad2 intron 3. Further analyses are required to identify the exact function of PPR20 and Zm_mTERF15 in the splicing of nad2 intron 3.


Assuntos
Complexo I de Transporte de Elétrons/metabolismo , Íntrons/fisiologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Splicing de RNA , Sementes/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Alelos , Complexo I de Transporte de Elétrons/genética , Regulação da Expressão Gênica de Plantas , Proteínas Mitocondriais/genética , Mutação , Fenótipo , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Ligação a RNA , Sementes/citologia , Sementes/genética , Zea mays/genética
6.
Med Sci Monit ; 26: e922160, 2020 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-32504527

RESUMO

BACKGROUND A high-salt diet may result in chronic disease and changes in the intestinal microbiota. This pilot study aimed to investigate the microbial composition of the intestine in Wistar rats given intragastric high-salt infusions for four weeks. MATERIAL AND METHODS Six 4-week-old male Wistar rats were fed standard chow and divided into the high-salt group (n=3) and the control study group (n=3). Rats in the high-salt group were given 1 ml of 10% NaCl solution intragastrically three times per week for four weeks. The fecal pellets were collected, and the microbiota was characterized using 16S rRNA gene sequencing that targeted the V4 region. The relative abundance of microbial populations was compared using linear discriminant analysis effect size (LEfSe) statistical analysis for the identification of biomarkers between two or more groups, principal component analysis (PCA), and linear discriminant analysis (LDA). Microbial genome prediction was performed using the phylogenetic investigation of communities by reconstructing the unobserved states (PICRUSt) bioinformatics software. RESULTS There was no significant difference in the alpha diversity of the fecal microbiota between the high-salt group and the control group. However, PCA showed structural segregation between the two groups. Further analysis using LEfSe showed that the intestinal contents in the high-salt group had significantly reduced populations of Lactobacillus and Prevotella NK3B31, and a significant increase in Alloprevotella and Prevotella 9, without physiological or pathological changes. CONCLUSIONS A pilot study in Wistar rats showed that high-salt intake was associated with a change in the composition of the intestinal microbiota.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Cloreto de Sódio na Dieta/efeitos adversos , Animais , Bactérias/genética , Fezes/microbiologia , Intestinos/microbiologia , Masculino , Filogenia , Projetos Piloto , RNA Ribossômico 16S/análise , Ratos , Ratos Wistar , Cloreto de Sódio/metabolismo , Estômago/microbiologia
7.
J Clin Lab Anal ; 34(11): e23465, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32638440

RESUMO

BACKGROUND: The trends in usage of tumor markers, including CEA, SCC, NSE, Cyfra21-1, and ProGRP, in Chinese lung cancer patients in the real-world setting are not fully investigated. METHODS: A retrospective descriptive study was conducted using the database of Qilu Hospital of Shandong University, China between January 2013 and December 2017, involving patients primarily diagnosed with NSCLC or SCLC. Utilization trends by first discharge year, utilization rates within different durations before and after first discharge date, and combined utilization patterns of multiple tumor markers were analyzed. RESULTS: The utilization of all these tumor markers showed increased from 2013 to 2017. CEA, Cyfra21-1, and NSE were the most frequently detected, which increased slightly from around 50% in 2013 to around 78% in 2017 in NSCLC and from around 70% in 2013 to around 92% in 2017 in SCLC. CEA, Cyfra21-1, and NSE were the most commonly measured within 3 months before first diagnosis with approximately 65% in NSCLC and 80% in SCLC, and ProGRP had the lowest utilization (around 30%). CEA, NSE, and Cyfra21-1 had the highest utilization rates after first diagnosis with both around 80% in NSCLC or SCLC. Combined usage of five tumor markers was ranked the first pattern in combined utilization. CONCLUSIONS: This study suggests CEA, Cyfra21-1, and NSE are the most frequently detected before or after first diagnosis of NSCLC or SCLC. However, SCC and ProGRP tests appeared to have relatively low usages. The utilization pattern was consistent with recommendations of guideline, but underutilization still existed.


Assuntos
Biomarcadores Tumorais/sangue , Detecção Precoce de Câncer/estatística & dados numéricos , Neoplasias Pulmonares , Adolescente , Adulto , Idoso , China , Feminino , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Nano Lett ; 19(5): 3280-3287, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31009570

RESUMO

All-solid-state lithium-sulfur batteries (ASSLSBs) have attracted great attention due to their inherent ability to eliminate the two critical issues (polysulfide shuttle effect and safety) of traditional liquid electrolyte based Li-S batteries. However, it remains a huge challenge for ASSLSBs to achieve high areal active mass loading and high active material utilization simultaneously due to the insulating nature of sulfur and Li2S, and the large volume change during cycling. Herein, a Li2S@C nanocomposite with Li2S nanocrystals uniformly embedded in conductive carbon matrix, is in situ generated by the combustion of lithium metal with CS2. Benefiting from its unique architecture, the Li2S@C exhibits exceptional electrochemical performance as cathode for ASSLSBs, with both ultrahigh areal Li2S loading (7 mg cm-2) and 91% of Li2S utilization (corresponding to a reversible capacity of 1067 mAh g-1). Moreover, the Li2S@C also possesses outstanding rate capability and cycling stability. High reversible capacity of 644 mAh g-1 is delivered at 2 mA cm-2 even after 700 cycles. This work demonstrates that ASSLSBs with superior electrochemical performance can be realized via rational design of the cathode structure, which provides a promising prospect to the development of ASSLSBs with practical energy density surpassing that of lithium ion batteries.

9.
J Integr Plant Biol ; 62(6): 777-792, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31332949

RESUMO

In land plants, cytidine-to-uridine (C-to-U) editing of organellar transcripts is an important post-transcriptional process, which is considered to remediate DNA genetic mutations to restore the coding of functional proteins. Pentatricopeptide repeat (PPR) proteins have key roles in C-to-U editing. Owing to its large number, however, the biological functions of many PPR proteins remain to be identified. Through characterizing a small kernel4 (smk4) mutant, here we report the function of Smk4 and its role in maize growth and development. Null mutation of Smk4 slows plant growth and development, causing small plants, delayed flowering time, and small kernels. Cloning revealed that Smk4 encodes a new E-subclass PPR protein, and localization indicated that SMK4 is exclusively localized in mitochondria. Loss of Smk4 function abolishes C-to-U editing at position 1489 of the cytochrome c oxidase1 (cox1) transcript, causing an amino acid change from serine to proline at 497 in Cox1. Cox1 is a core component of mitochondrial complex IV. Indeed, complex IV activity is reduced in the smk4, along with drastically elevated expression of alternative oxidases (AOX). These results indicate that SMK4 functions in the C-to-U editing of cox1-1489, and this editing is crucial for mitochondrial complex IV activity, plant growth, and kernel development in maize.


Assuntos
Mitocôndrias/metabolismo , Edição de RNA , Sementes/embriologia , Sementes/genética , Zea mays/embriologia , Zea mays/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Respiração Celular , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação/genética , Fenótipo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sequências Repetitivas de Aminoácidos
10.
Plant J ; 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30003606

RESUMO

Splicing of plant organellar group II introns is under accurate nuclear control that employs many nucleus-encoded protein cofactors from various families. For mitochondrial introns, only a few splicing factors have been characterized because disruption of their functions often causes embryo lethality. Here, we report the function of Empty Pericarp8 (Emp8) in the splicing of three group II introns in mitochondria, complex I biogenesis, and seed development in maize. Emp8 encodes a P subfamily pentatricopeptide repeat protein that localizes in mitochondria. The loss-of-function mutants of Emp8 are embryo lethal, showing severely arrested embryo and endosperm development in maize. The respiration rate in the emp8 mutants is reduced with substantially enhanced expression of alternative oxidases. Transcript analysis indicated that the trans-splicing of nad1 intron 4 and cis-splicing of nad4 intron 1 are abolished, and the cis-splicing of nad2 intron 1 is severely impaired in the emp8 mutants. These defects consequently lead to the disassembly of mitochondrial complex I and a dramatic reduction in its activity. Together, these results suggest that Emp8 is required for the trans-splicing of nad1 intron 4 and cis-splicing of nad4 intron 1 and nad2 intron 1, which is essential to mitochondrial complex I assembly and hence to embryogenesis and endosperm development in maize.

11.
New Phytol ; 221(2): 896-907, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30168136

RESUMO

RNA editing plays an important role in organellar gene expression in plants, and pentatricopeptide repeat (PPR) proteins are involved in this function. Because of its large family size, many PPR proteins are not known for their function and roles in plant growth and development. Through genetic and molecular analyses of the empty pericarp18 (emp18) mutant in maize (Zea mays), we cloned the Emp18 gene, revealed its molecular function, and defined its role in the mitochondrial complex assembly and seed development. Emp18 encodes a mitochondrial-localized DYW-PPR protein. Null mutation of Emp18 arrests embryo and endosperm development at an early stage in maize, resulting in embryo lethality. Mutants are deficient in the cytidine (C)-to-uridine (U) editing at atp6-635 and cox2-449, which converts a Leu to Pro in ATP6 and a Met to Thr in Cox2. The atp6 gene encodes the subunit a of F1 Fo -ATPase. The Leu to Pro alteration disrupts an α-helix of subunit a, resulting in a dramatic reduction in assembly and activity of F1 Fo -ATPase holoenzyme and an accumulation of free F1 -subcomplex. These results demonstrate that EMP18 functions in the C-to-U editing of atp6 and cox2, and is essential to mitochondrial biogenesis and seed development in maize.


Assuntos
Proteínas Mitocondriais/metabolismo , Edição de RNA , Zea mays/genética , Mitocôndrias/genética , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/genética , Mutação , Biogênese de Organelas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/ultraestrutura , Zea mays/crescimento & desenvolvimento , Zea mays/ultraestrutura
12.
J Exp Bot ; 70(19): 5245-5258, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31257441

RESUMO

Group II introns are ribozymes that can excise themselves from precursor-RNA transcripts, but plant organellar group II introns have structural deviations that inhibit ribozyme activity. Therefore, splicing of these introns requires the assistance of nuclear- and/or organellar-encoded splicing factors; however, how these splicing factors function remains unclear. In this study, we report the functions and interactions of two splicing factors, PPR-SMR1 and Zm-mCSF1, in intron splicing in maize mitochondria. PPR-SMR1 is a SMR domain-containing pentatricopeptide repeat (PPR) protein and Zm-mCSF1 is a CRM domain-containing protein, and both are targeted to mitochondria. Loss-of-function mutations in each of them severely arrests embryogenesis and endosperm development in maize. Functional analyses indicate that PPR-SMR1 and Zm-mCSF1 are required for the splicing of most mitochondrial group II introns. Among them, nad2-intron 2 and 3, and nad5-intron 1 are PPR-SMR1/Zm-mCSF1-dependent introns. Protein interaction assays suggest that PPR-SMR1 can interact with Zm-mCSF1 through its N-terminus, and that Zm-mCSF1 is self-interacting. Our findings suggest that PPR-SMR1, a novel splicing factor, acts in the splicing of multiple group II introns in maize mitochondria, and the protein-protein interaction between it and Zm-mCSF1 might allow the formation of large macromolecular splicing complexes.


Assuntos
Proteínas de Plantas/genética , Sementes/crescimento & desenvolvimento , Zea mays/genética , Íntrons , Mitocôndrias/metabolismo , Mutação , Proteínas de Plantas/metabolismo , Splicing de RNA , Sementes/genética , Sementes/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
13.
Pestic Biochem Physiol ; 153: 28-35, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30744894

RESUMO

The high activity and broad weed spectrum of BS has made it widely used in China. However, accidental crop injuries, particularly occurring in Jiangsu, Hunan, Hubei and Heilongjiang provinces in recent years, have resulted in limiting the application of BS in China. In this study, glutathione homeostasis was measured in the contrasting sensitivity of indica and japonica rice cultivar after bispyribac-sodium (BS) treatment. The results showed that japonica rice cultivar Nanjing 9108 was more sensitive to BS than indica rice Nanjing 11 and indica-hybrid cultivar Guangliangyou 6326. In response to the exposure of BS in all rice cultivars, especially Nanjing 9108, the perturbation of glutathione homeostasis occurred, including the decreased reduced glutathione (GSH) and increased oxidized glutathione (GSSG). These results were supported by increased activities of glutathione S-transferases (GSTs) in Nanjing 11 and Guangliangyou 6326. Further tests revealed that when Nanjing 11 was pretreated with the glutathione-depleting agents L-buthionine-sulfoximine (BSO) or diethylmaleate (DEM), the GSH levels, the activity of GSTs, and the gene expression levels of GR and GSTs decreased, finally increasing the phytotoxicity of BS. The aforementioned DEM inhibitory responses were further rescued by exogenously applied GSH. In contrast, the pretreatment of glutathione or N-acetyl-L-cysteine (NAC) not only increased the contents of GSH, the activities of GSTs, and the expression level of GR and GSTs gene, but also alleviated BS phytotoxicity in Nanjing 9108. In both cultivars, DEM increased phytotoxicity and GSH partially reversed this. This study suggests that increasing tolerance to BS was able to allow glutathione homeostasis to recover in indica rice cultivar compared with japonica rice cultivar.


Assuntos
Benzoatos/toxicidade , Glutationa/metabolismo , Herbicidas/toxicidade , Oryza/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Pirimidinas/toxicidade , Resistência a Herbicidas , Homeostase , Oryza/metabolismo
14.
New Phytol ; 214(2): 782-795, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28121385

RESUMO

Pentatricopeptide repeat (PPR) proteins comprise a large family of sequence-specific RNA binding proteins in land plants. Because of its large family size and frequent embryo lethality in the mutants, molecular functions and physiological roles of many PPR proteins are unknown. Through characterization of an empty pericarp9 (emp9) mutant in maize (Zea mays), we defined the functions of EMP9 in mitochondrial RNA editing, respiratory complex formation and seed development. Mu insertions in different regions of Emp9 facilitated dissection of the domain functions of the EMP9. Through genetic and functional analyses of multiple alleles, we showed that deletions of two N-terminal PPR motifs and partial E+ domain do not eliminate the editing function of EMP9. Emp9 encodes an E+ subclass PPR protein that is localized in mitochondria. Loss of EMP9 function abolishes the C-to-U editing of ccmB-43 and rps4-335 sites in mitochondria. The loss of editing at ccmB-43 and rps4-335 affects the maturation of cytochrome c and impairs the biogenesis of mitochondrial respiratory complexes, particularly complex III. This work extends our understanding of PPR-E+ protein in editing function and seed development, and provides insights into the molecular function of mitochondrial CcmB protein in higher plants.


Assuntos
Mitocôndrias/metabolismo , Biogênese de Organelas , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Edição de RNA/genética , Sementes/genética , Zea mays/embriologia , Zea mays/genética , Alelos , Arabidopsis/genética , Sequência de Bases , Endosperma/embriologia , Endosperma/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Mutação com Perda de Função , Plantas Geneticamente Modificadas , Sementes/embriologia
15.
Int J Psychol ; 51(2): 123-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640308

RESUMO

This research focuses on investigating whether organisational identification mediates the effects of job security on in-role behaviour and extra-role behaviour and how these mediation mechanisms differ according to gender. Through analysing 212 supervisor-subordinate dyads from a Chinese air transportation group, the research indicated that organisational identification partially mediated the effect of job security on in-role behaviour and fully mediated the effect of job security on extra-role behaviour. A multi-group analysis also showed that there were significant differences between male and female employees in these relationships. In addition, moderated mediation analyses showed that gender moderated the indirect effects of job security on in-role behaviour and extra-role behaviour through organisational identification. Limitations and implications of these findings are discussed.


Assuntos
Satisfação no Emprego , Identificação Social , Desempenho Profissional , China , Feminino , Humanos , Masculino , Inquéritos e Questionários
16.
BMC Cancer ; 14: 886, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25428027

RESUMO

BACKGROUND: We previously demonstrated that 6-benzylthioinosine (6-BT) could induce the differentiation of a subset of acute myeloid leukemia (AML) cell lines and primary AML cells regardless of their cytogenetics. In this study we investigated whether Wnt signaling pathways played roles in 6-BT-induced differentiation of AML cells. METHODS: We induced differentiation of HL-60 leukemic cells and primary AML cells in vitro using 6-BT. Real-time PCR (qPCR), western blot, and luciferase assays were used to examine the molecules' expression and biological activity in canonical and noncanonical Wnt signaling pathways. AML cell differentiation was measured by the Nitroblue tetrozolium (NBT) reduction assay. RESULTS: 6-BT regulated the expression of both canonical and non-canonical Wnt signaling molecules in HL-60 cells. Both 6-BT and all-trans-retinoic-acid (ATRA) reduced canonical Wnt signaling and activated noncanonical Wnt/Ca2+ signaling in HL-60 cells. Pre-treatment of HL-60 cells with an inhibitor of glycogen synthase kinase-3ß (GSK-3ß), which activated canonical Wnt signaling, partly abolished the differentiation of HL-60 cells induced by 6-BT. Pre-treatment of HL-60 cells with an inhibitor of protein kinase C (PKC), resulting in inactivation of non-canonical Wnt/Ca2+ signaling, abolished 6-BT-induced differentiation of HL-60 cells. Several molecules in the non-canonical Wnt/Ca2+ pathway were detected in bone marrow samples from AML patients, and the expression of FZD4, FZD5, Wnt5a and RHOU were significantly reduced in newly diagnosed AML samples compared with normal controls. CONCLUSIONS: Both canonical and non-canonical Wnt signaling were involved in 6-BT-induced differentiation of HL-60 cells, and played opposite roles in this process. Wnt signaling could be involved in the pathogenesis of AML not only by regulating self-renewal of hematopoietic stem cells, but also by playing a role in the differentiation of AML cells.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Tioinosina/análogos & derivados , Via de Sinalização Wnt/efeitos dos fármacos , Sinalização do Cálcio , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Tioinosina/farmacologia , Tretinoína/farmacologia
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 945-951, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38926993

RESUMO

OBJECTIVE: To explore the application value of simultaneous monitoring of voriconazole (VRCZ) and voriconazole N-oxide (VNO) in efficacy and safety of VRCZ in the prevention and treatment of fungal infections in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients before engraftment (i.e., days +1 to +30 after transplantation). METHODS: The influencing factors of VRCZ, VNO concentration and MR (CVNO/CVRCZ) and the difference of VRCZ in the prevention and treatment of fungal infection and liver and kidney injury were analyzed. The receiver operating characteristic curve (ROC) was used to analyze the differences (the corresponding to the maximum of the Youden index on the curve was set as the cut-off value) to confirm the critical value. RESULTS: The factors affecting VRCZ concentration (CVRCZ), VNO concentration (CVNO) and MR were patient weight, VRCZ daily dose, and transplantation type (all P < 0.05). CVRCZ and CVNO in the effective group were higher than those in the ineffective group (P < 0.001), the opposite of MR (P < 0.001); the liver and renal injury group had lower MR than the normal group (P < 0.05). ROC showed that CVRCZ, C VNO and MR had important value in predicting VRCZ in the prevention and treatment of invasive fungal infections in allo-HSCT patients before engraftment, and their cutoff of concentrations were 0.95 µg/ml, 1.35 µg/ml and 1.645, respectively (AUC: 0.9677, 0.7634, 0.9564). CVRCZ and MR can assist in indicating liver ï¼»cutoff values: 0.65 µg/ml, 1.96 (AUC: 0.5971, 0.6663)ï¼½ and renal injury ï¼»cutoff values: 0.95 µg/ml, 1.705 (AUC: 0.6039, 0.6164)ï¼½. CONCLUSION: The great value of simultaneous monitoring of VRCZ, VNO and MR can predict in the efficacy and safety of VRCZ in allo-HSCT patients before engraftment. The prediction accuracy of CVRCZ was higher than that of MR, followed by that of CVNO. Increased CVRCZ and decreased MR increase the risk of liver and kidney injury.


Assuntos
Antifúngicos , Transplante de Células-Tronco Hematopoéticas , Transplante Homólogo , Voriconazol , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Micoses , Monitoramento de Medicamentos/métodos
18.
BMC Public Health ; 13: 529, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23721370

RESUMO

BACKGROUND: Comprehensive smoke-free legislation has been implemented in many countries. The current study quantitatively examined the reduction in risk of acute myocardial infarction (MI) occurrence following the legislations and the relationship with the corresponding smoking prevalence decrease. METHODS: PubMed, EMBASE, and Google Scholar databases and bibliographies of relevant studies and reviews were searched for potential original studies published from January 1, 2004, through October 31, 2011. Meta-analysis was performed using a random effect model to estimate the overall effects of the smoking-free legislations. Meta-regression was used to investigate possible causes of heterogeneity in risk estimates. RESULTS: A total of 18 eligible studies with 44 estimates of effect size were used in this study. Meta-analysis produced a pooled estimate of the relative risk of 0.87 (95% confidence interval (CI): 0.84 to 0.91). There was significant heterogeneity in the risk estimates (overall I² = 96.03%, p<0.001). In meta-regression analysis, studies with greater smoking prevalence decrease produced larger relative risk (adjusted coefficient -0.027, 95% CI: -0.049 to -0.006, p=0.014). CONCLUSION: Smoke-free legislations in public and work places were associated with significant reduction in acute MI risk, which might be partly attributable to reduced smoking prevalence.


Assuntos
Infarto do Miocárdio/prevenção & controle , Política Antifumo/legislação & jurisprudência , Poluição por Fumaça de Tabaco/efeitos adversos , Poluição do Ar em Ambientes Fechados/prevenção & controle , Humanos , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
19.
Pestic Biochem Physiol ; 107(3): 334-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24267695

RESUMO

Herbicide resistance or tolerance in weeds mediated by cytochrome P450 monooxygenase is a considerable problem. However, cytochrome P450 mediated resistance or tolerance in weeds was less studied. Thus, in this work, the role of the cytochrome P450 monooxygenase in the different responses of Poa annua and Alopecurus aequalis to fenoxaprop-P-ethyl was studied. We found that the effect of fenoxaprop-P-ethyl could be synergized by piperonyl butoxide (PBO) in P. annua, but not by malathion. After being treated with fenoxaprop-P-ethyl (containing mefenpyr-diethyl), the contents of cytochrome P450 and cytochrome b5 in P. annua increased significantly compared to plants treated with mefenpyr-diethyl only or untreated plants. However, the increase was less in A. aequalis, which was susceptible to fenoxaprop-P-ethyl. The activities of ρ-nitroanisole O-demethylase (PNOD), ethoxyresorufin O-deethylase (EROD), ethoxycoumarin oxidase (ECOD) and NADPH-dependent cytochrome P450 reductase mediated by cytochrome P450 monooxygenase increased in P. annua after treatment with fenoxaprop-P-ethyl, especially the activities of ECOD and cytochrome P450 reductase. Besides this, cytochrome P450 monooxygenase activity toward fenoxaprop-P-ethyl in P. annua increased significantly compared to untreated or treated with mefenpyr-diethyl plants and treated or untreated A. aequalis. Cytochrome P450 monooxygenase may play an important role in the different responses to fenoxaprop-P-ethyl in P. annua and A. aequalis.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Poa/enzimologia , Poaceae/enzimologia , Sistema Enzimático do Citocromo P-450/genética , Oxazóis/farmacologia , Butóxido de Piperonila/metabolismo , Poa/efeitos dos fármacos , Poaceae/efeitos dos fármacos , Propionatos/farmacologia
20.
Pestic Biochem Physiol ; 107(1): 25-31, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25149231

RESUMO

Japanese foxtail is one of the most common and troublesome weeds infesting cereal and oilseed rape fields in China. Repeated use during the last three decades of the ACCase-inhibiting herbicide fenoxaprop-P-ethyl to control this weed has resulted in the occurrence of resistance. Dose-response tests established that a population (AHFD-1) from eastern China had evolved high-level resistance to fenoxaprop-P-ethyl. Based on the resistance index, this resistant population of A. japonicus is 60.31-fold resistant to fenoxaprop-P-ethyl. Subsequently, only a tryptophan to cysteine substitution was identified to confer resistance to fenoxaprop-P-ethyl in this resistant population. ACCase activity tests further confirmed this substitution was linked to resistance. This is the first report of the occurrence of Trp-2027-Cys substitution of ACCase in A. japonicus. From whole-plant pot dose-response tests, we confirmed that this population conferred resistance to other APP herbicides, including clodinafop-propargyl, fluazifop-P-butyl, quizalofop-P-ethyl, haloxyfop-R-methyl, cyhalofop-butyl, metamifop, DEN herbicide pinoxaden, but not to CHD herbicides clethodim, sethoxydim. There was also no resistance observed to ALS-inhibiting herbicides sulfosulfuron, mesosulfuron-methyl, flucarbazone-sodium, pyroxsulam, Triazine herbicide prometryne and glyphosate. However, this resistant population was likely to confer slightly (or no) resistant to Urea herbicides chlortoluron and isoproturon.


Assuntos
Acetil-CoA Carboxilase/genética , Herbicidas/farmacologia , Oxazóis/farmacologia , Proteínas de Plantas/genética , Plantas Daninhas/efeitos dos fármacos , Poaceae/efeitos dos fármacos , Propionatos/farmacologia , Acetil-CoA Carboxilase/antagonistas & inibidores , Acetil-CoA Carboxilase/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , China , Cisteína/genética , DNA de Plantas/genética , Resistência a Herbicidas/genética , Dados de Sequência Molecular , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/metabolismo , Plantas Daninhas/enzimologia , Plantas Daninhas/genética , Poaceae/enzimologia , Poaceae/genética , Triptofano/genética
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