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1.
Mol Psychiatry ; 28(3): 1383-1395, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36481932

RESUMO

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.


Assuntos
Sistema Hipotálamo-Hipofisário , Receptores de Glucocorticoides , Feminino , Gravidez , Animais , Camundongos , Sistema Hipotálamo-Hipofisário/metabolismo , Receptores de Glucocorticoides/metabolismo , Glucocorticoides/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Homeostase
2.
Plant Mol Biol ; 113(6): 415-430, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566350

RESUMO

Cadmium (Cd) is a non-essential heavy metal, assimilated in plant tissue with other nutrients, disturbing the ions' homeostasis in plants. The plant develops different mechanisms to tolerate the hazardous environmental effects of Cd. Recently studies found different miRNAs that are involved in Cd stress. In the current study, miR397 mutant lines were constructed to explore the molecular mechanisms of miR397 underlying Cd tolerance. Compared with the genetically modified line of overexpressed miR397 (artificial miR397, amiR397), the lines of downregulated miR397 (Short Tandem Target Mimic miR397, STTM miR397) showed more substantial Cd tolerance with higher chlorophyll a & b, carotenoid and lignin content. ICP-OES revealed higher cell wall Cd and low total Cd levels in STTM miR397 than in the wild-type and amiR397 plants.Further, the STTM plants produced fewer reactive oxygen species (ROS) and lower activity of antioxidants enzymes (e.g., catalase [CAT], malondialdehyde [MDA]) compared with amiR397 and wild-type plants after stress, indicating that silencing the expression of miR397 can reduce oxidative damage. In addition, the different family transporters' gene expression was much higher in the amiR397 plants than in the wild type and STTM miRNA397. Our results suggest that miR397 plays a role in Cd tolerance in Arabidopsis thaliana. Overexpression of miR397 could decrease Cd tolerance in plants by regulating the expression of LAC 2/4/17, changing the lignin content, which may play an important role in inducing different stress-tolerant mechanisms and protecting the cell from a hazardous condition. This study provides a basis to elucidate the functions of miR397 and the Cd stress tolerance mechanism in Arabidopsis thaliana.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Cádmio/metabolismo , Lignina/metabolismo , Clorofila A/metabolismo , Antioxidantes/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Immunopharmacol Immunotoxicol ; 45(6): 754-760, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37485845

RESUMO

OBJECTIVE: Toll-like receptor 4 (TLR4) is crucial in induction of innate immune response through recognition of invading pathogens or endogenous alarming molecules. Ligand-triggered dimerization of TLR4 is essential for the activation of NF-κB and IRF3 through MyD88- or TRIF-dependent pathways. Saquinavir (SQV), an FDA-approved HIV protease inhibitor, has been shown to attenuate the activation of NF-κB induced by HMGB1 by blocking TLR4-MyD88 association in proteasome independent pathway. This study aims to define whether SQV is an HMGB1-specific and MyD88-dependent TLR4 signaling inhibitor and which precise signaling element of TLR4 is targeted by SQV. MATERIALS AND METHODS: PMA differentiated human THP-1 macrophages or reconstituted HEK293 cells were pretreated with SQV before stimulated by different TLR agonists. TNF-α level was evaluated through ELISA assay. NF-κB activation was analyzed using NF-κB SEAP reporting system. The levels of MyD88/TRIF pathways-related factors were examined by immunoblot. TLR4 endocytosis was assessed by immunocytochemistry. TLR4 dimerization was determined using immunoprecipitation between different tagged TLR4 and an in silico molecular docking experiment was performed to explore the possible binding site of SQV on its target. RESULTS: Our data showed that SQV suppresses both MyD88- and TRIF-dependent pathways in response to lipopolysaccharide (LPS), a critical sepsis inducer and TLR4 agonist, leading to downregulation of NF-κB and IRF3. SQV did not suppress MyD88-dependent pathway triggered by TLR1/2 agonist Pam3csk4. In the only TRIF-dependent pathway, SQV did not alleviate IRF3 phosphorylation induced by TLR3 agonist Poly(I:C). Furthermore, dimerization of TLR4 following LPS or HMGB1 stimulation was decreased by SQV. CONCLUSION: We concluded that TLR4 receptor complex is one of the mammalian targets of SQV, and TLR4-mediated immune responses and consequent risk for uncontrolled inflammation could be modulated by FDA-approved drug SQV.


Assuntos
Inibidores da Protease de HIV , Proteína HMGB1 , Animais , Humanos , Receptor 4 Toll-Like/metabolismo , Saquinavir/farmacologia , NF-kappa B/metabolismo , Proteína HMGB1/metabolismo , Fator 88 de Diferenciação Mieloide , Dimerização , Lipopolissacarídeos/farmacologia , Células HEK293 , Simulação de Acoplamento Molecular , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Mamíferos/metabolismo
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(6): 696-700, 2023 Jun 10.
Artigo em Zh | MEDLINE | ID: mdl-37212005

RESUMO

OBJECTIVE: To explore the clinical characteristics and genetic basis of a child with Mental retardation autosomal dominant 51 (MRD51). METHODS: A child with MRD51 who was hospitalized at Guangzhou Women and Children's Medical Center on March 4, 2022 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and her parents were collected and subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a 5-year-and-3-month-old girl, had manifested autism spectrum disorder (ASD), mental retardation (MR), recurrent febrile convulsions and facial dysmorphism. WES revealed that she has harbored a novel heterozygous variant of c.142G>T (p.Glu48Ter) in the KMT5B gene. Sanger sequencing confirmed that neither of her parents has carried the same variant. The variant has not been recorded in the ClinVar, OMIM and HGMD, ESP, ExAC and 1000 Genomes databases. Analysis with online software including Mutation Taster, GERP++ and CADD indicated it to be pathogenic. Prediction with SWISS-MODEL online software suggested that the variant may have a significant impact on the structure of KMT5B protein. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic. CONCLUSION: The c.142G>T (p.Glu48Ter) variant of the KMT5B gene probably underlay the MRD51 in this child. Above finding has expanded the spectrum of KMT5B gene mutations and provided a reference for clinical diagnosis and genetic counseling for this family.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Humanos , Feminino , Pré-Escolar , Deficiência Intelectual/genética , Transtorno do Espectro Autista/genética , Mutação
5.
Environ Res ; 212(Pt B): 113289, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35427592

RESUMO

The cartridge filter (CF) as a "firewall" is crucial between pretreatment and nanofiltration (NF) units, but CF fouling with risk has received limited attention. The systematic autopsy for CFs (CF1 and CF2) applied in a NF drinking water plant was conducted to reveal CF fouling profile. Herein, scale blocks, irregular-shaped particles, and stacked-floc clusters were observed as the main morphologies of foulants. The major elements from foulants included Fe, Ca, Al, Mg, Na, P, and Si. The dissolved matters especially bioproducts resulted in the secondary pollution of permeated water. Biofouling was mainly caused by Proteobacteria phyla, and consisted of a large proportion of polysaccharides (11% and 25.1%), proteins (10.3% and 22.7%), lipids (21.7% and 22.4%), respectively. In addition, an obvious contrast was observed regarding the antifouling performance of CFs. The surface scaling degree of CF1 with horizontal irregular loose-pleats was more serious than CF2 with vertical regular compact-pleats, while the latter with high-density pleats appeared the higher fouling potential due to a greater capacity for organic foulants in the inner layers of "firewall" and better bio-diversity and bio-evenness of microbial communities. This study provides a deeper insight into CF fouling and contributes to the application of CFs.


Assuntos
Incrustação Biológica , Água Potável , Purificação da Água , Incrustação Biológica/prevenção & controle , Humanos , Membranas Artificiais , Purificação da Água/métodos
6.
Sensors (Basel) ; 22(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36146404

RESUMO

Synthetic aperture radar (SAR) is an important remote sensing sensor whose application is becoming more and more extensive. Compared with traditional optical sensors, it is not easy to be disturbed by the external environment and has a strong penetration. Limited by its working principles, SAR images are not easily interpreted, and fusing SAR images with optical multispectral images is a good solution to improve the interpretability of SAR images. This paper presents a novel image fusion method based on non-subsampled shearlet transform and activity measure to fuse SAR images with multispectral images, whose aim is to improve the interpretation ability of SAR images easily obtained at any time, rather than producing a fused image containing more information, which is the pursuit of previous fusion methods. Three different sensors, together with different working frequencies, polarization modes and spatial resolution SAR datasets, are used to evaluate the proposed method. Both visual evaluation and statistical analysis are performed, the results show that satisfactory fusion results are achieved through the proposed method and the interpretation ability of SAR images is effectively improved compared with the previous methods.

7.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36232465

RESUMO

As an important agronomic trait in rice (Oryza sativa), moderate leaf rolling helps to maintain the erectness of leaves and minimize shadowing between leaves, leading to improved photosynthetic efficiency and grain yield. However, the molecular mechanisms underlying rice leaf rolling still need to be elucidated. Here, we isolated a rice mutant, rl89, showing adaxially rolled leaf phenotype due to decreased number and size of bulliform cells. We confirmed that the rl89 phenotypes were caused by a single nucleotide substitution in OsDRB2 (LOC_Os10g33970) gene encoding DOUBLE-STRANDED RNA-BINDING2. This gene was constitutively expressed, and its encoded protein was localized to both nucleus and cytoplasm. Yeast two-hybrid assay showed that OsDRB2 could interact with DICER-LIKE1 (DCL1) and OsDRB1-2 respectively. qRT-PCR analysis of 29 related genes suggested that defects of the OsDRB2-miR166-OsHBs pathway could play an important role in formation of the rolled leaf phenotype of rl89, in which OsDRB2 mutation reduced miR166 accumulation, resulting in elevated expressions of the class III homeodomain-leucine zipper genes (such as OsHB1, 3 and 5) involved in leaf polarity and/or morphology development. Moreover, OsDRB2 mutation also reduced accumulation of miR160, miR319, miR390, and miR396, which could cause the abnormal leaf development in rl89 by regulating expressions of their target genes related to leaf development.


Assuntos
MicroRNAs , Oryza , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação , Nucleotídeos/metabolismo , Oryza/metabolismo , Fenótipo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , RNA de Cadeia Dupla/metabolismo
8.
Int J Mol Sci ; 23(10)2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35628595

RESUMO

Protoporphyrinogen IX (Protogen IX) oxidase (PPO) catalyzes the oxidation of Protogen IX to Proto IX. PPO is also the target site for diphenyl ether-type herbicides. In plants, there are two PPO encoding genes, PPO1 and PPO2. To date, no PPO gene or mutant has been characterized in monocotyledonous plants. In this study, we isolated a spotted and rolled leaf (sprl1) mutant in rice (Oryza sativa). The spotted leaf phenotype was sensitive to high light intensity and low temperature, but the rolled leaf phenotype was insensitive. We confirmed that the sprl1 phenotypes were caused by a single nucleotide substitution in the OsPPO1 (LOC_Os01g18320) gene. This gene is constitutively expressed, and its encoded product is localized to the chloroplast. The sprl1 mutant accumulated excess Proto(gen) IX and reactive oxygen species (ROS), resulting in necrotic lesions. The expressions of 26 genes associated with tetrapyrrole biosynthesis, photosynthesis, ROS accumulation, and rolled leaf were significantly altered in sprl1, demonstrating that these expression changes were coincident with the mutant phenotypes. Importantly, OsPPO1-overexpression transgenic plants were resistant to the herbicides oxyfluorfen and acifluorfen under field conditions, while having no distinct influence on plant growth and grain yield. These finding indicate that the OsPPO1 gene has the potential to engineer herbicide resistance in rice.


Assuntos
Herbicidas , Oryza , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Mutação , Oryza/genética , Oryza/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Protoporfirinogênio Oxidase/genética , Protoporfirinogênio Oxidase/metabolismo , Espécies Reativas de Oxigênio
9.
Int J Mol Sci ; 23(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35742907

RESUMO

The circadian clock and histone modifications could form a feedback loop in Arabidopsis; whether a similar regulatory mechanism exists in rice is still unknown. Previously, we reported that SDG724 and OsLHY are two rice heading date regulators in rice. SDG724 encodes a histone H3K36 methyltransferase, and OsLHY is a vital circadian rhythm transcription factor. Both could be involved in transcription regulatory mechanisms and could affect gene expression in various pathways. To explore the crosstalk between the circadian clock and histone methylation in rice, we studied the relationship between OsLHY and SDG724 via the transcriptome analysis of their single and double mutants, oslhy, sdg724, and oslhysdg724. Screening of overlapped DEGs and KEGG pathways between OsLHY and SDG724 revealed that they could control many overlapped pathways indirectly. Furthermore, we identified three candidate targets (OsGI, OsCCT38, and OsPRR95) of OsLHY and one candidate target (OsCRY1a) of SDG724 in the clock pathway. Our results showed a regulatory relationship between OsLHY and SDG724, which paved the way for revealing the interaction between the circadian clock and histone H3K36 methylation.


Assuntos
Arabidopsis , Relógios Circadianos , Oryza , Arabidopsis/genética , Arabidopsis/metabolismo , Relógios Circadianos/genética , Ritmo Circadiano/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Histona Metiltransferases , Histonas/genética , Histonas/metabolismo , Metilação , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética
10.
J Environ Sci (China) ; 117: 141-150, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35725066

RESUMO

UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5-1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro , Desinfecção , Halogenação , Peróxidos , Sulfametoxazol , Poluentes Químicos da Água/análise
11.
Mikrochim Acta ; 187(11): 614, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33073313

RESUMO

A novel molecularly imprinted ratiometric fluorescent probe was fabricated by simple sol-gel polymerization for selective and sensitive assay of C-type natriuretic peptide (CNP) in biosamples. Both the nitrobenzoxadiazole (NBD) and carbon dots (CDs) were located on the surface of silica, used as the detection signal and reference signal, respectively. For the turn-on-based probe, the fluorescence intensity of NBD could be quantitatively enhanced by CNP based on the strategy of photo-induced electron transfer (PET), while the fluorescence of CDs remained unchanged. The obtained probe exhibited excellent recognition selectivity and fast kinetics to CNP templates, and also showed good stability. The linear range of CNP determination was 5-80 pg mL-1 with a low detection limit of 2.87 pg mL-1. Finally, the probe was successfully applied to determine CNP in human serum samples and attained high recoveries between 97.3 and 104% with precisions below 4.7%. The result indicates that the proposed method has promising potential for the assay of trace peptides in complex matrices. Schematic illustration for the formation and determination mechanism of the probe.


Assuntos
Corantes Fluorescentes/química , Impressão Molecular/métodos , Peptídeo Natriurético Tipo C/química , Soro/química , Espectrometria de Fluorescência/instrumentação , Transporte de Elétrons , Fluorescência , Humanos , Sondas Moleculares , Oxidiazóis/química , Pontos Quânticos/química , Sensibilidade e Especificidade , Dióxido de Silício , Espectrometria de Fluorescência/métodos
12.
Zhongguo Zhong Yao Za Zhi ; 43(4): 748-754, 2018 Feb.
Artigo em Zh | MEDLINE | ID: mdl-29600650

RESUMO

Magnetic molecularly imprinted polymers(MMIPs) were prepared with ZL006 as template, acrylamide(AA) as the functional monomer, and acetonitrile as pore-forming agent; then Fourier transform infrared spectroscopy(FT-IR) and scanning electron microscopy(SEM) were used to characterize their forms and structures. Simultaneously, the MMIPs prepared previously were used as sorbents for dispersive magnetic solid phase extraction(DSPE) to capture and identify potential nNOS-PSD-95 uncouplers from extracts of Trifolium pratense and the the activities of the screened compounds were evaluated by the neuroprotective effect and co-immunoprecipitation test. The experiment revealed that the successfully synthesized MMIPs showed good dispersiveness, suitable particle size and good adsorption properties. Formononetin, prunetin and biochanin A were separated and enriched from Trifolium pratense by using the MMIPs as artificial antibodies and finally biochanin A was found to have higher cytoprotective action and uncoupling action according to the neuroprotective effect and co-immunoprecipitation test.


Assuntos
Impressão Molecular , Polímeros/química , Trifolium/química , Adsorção , Genisteína/química , Compostos Fitoquímicos/química , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier
13.
J Neuroinflammation ; 14(1): 74, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28376889

RESUMO

BACKGROUND: Gout is one of the common inflammatory arthritis which affects many people for inflicting unbearable pain. Macrophage-mediated inflammation plays an important role in gout. The uptake of monosodium urate (MSU) crystals by macrophages can lead to activation of NOD-like receptors containing a PYD 3 (NLRP3) inflammasome, thus accelerating interleukin (IL)-1ß production. Reactive oxygen species (ROS) promoted development of the inflammatory process through NLRP3 inflammasome. Our study aimed to find a food-derived compound to attenuate gout pain via the specific inhibition of the NLRP3 inflammasome in macrophages. METHODS: CD-1 mice were used to evaluate the degree of pain and the swelling dimension of joints after an intra-articular (IA) MSU injection in the ankle. The murine macrophage cell line Raw 264.7 was used to investigate the effects of procyanidins and the mechanism underlying such effects. Histological analysis was used to measure the infiltration of inflammatory cells. ROS produced from Raw 264.7 cells were evaluated by flow cytometry. Cell signaling was measured by Western blot assay and immunofluorescence. RESULTS: Procyanidins significantly attenuated gout pain and suppressed ankle swelling. Procyanidins also inhibited MSU-induced activation of the NLRP3 inflammasome and increase of IL-1ß. Furthermore, procyanidins decreased ROS levels in Raw 264.7 cells. CONCLUSIONS: Suppression of the NLRP3 inflammasome in macrophages contributes to the amelioration of gout pain by procyanidins.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/toxicidade , Extrato de Sementes de Uva/uso terapêutico , Inflamação/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Dor/complicações , Proantocianidinas/uso terapêutico , Animais , Tornozelo/fisiopatologia , Colchicina/análogos & derivados , Colchicina/farmacologia , Citocinas/metabolismo , Gota/induzido quimicamente , Gota/complicações , Inflamação/induzido quimicamente , Inflamação/complicações , Lipopolissacarídeos/farmacologia , Camundongos , Dor/tratamento farmacológico , Dor/etiologia , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Ácido Úrico/toxicidade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Environ Toxicol ; 30(8): 895-903, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24519877

RESUMO

This study explored the effects of humic acid (HA) on the toxicity of ZnO nanoparticles (nano-ZnO) and Zn(2+) to Anabaena sp. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse-amplitude modulated fluorometer. Results showed that nano-ZnO and Zn(2+) could inhibit Anabaena sp. growth with the EC50 (concentration for 50% of maximal effect) of 0.74 ± 0.01 and 0.3 ± 0.01 mg/L, respectively. In the presence of 3.0 mg/L of HA, EC50 of nano-ZnO increased to 1.15 ± 0.04 mg/L and EC50 of Zn(2+) was still 0.3 ± 0.01 mg/L. Scanning electron microscopy observation revealed that HA prevented the adhesion of nano-ZnO on the algae cells due to the increased electrostatic repulsion. The generation of intracellular reactive oxygen species and cellular lipid peroxidation were significantly limited by HA. Nano-ZnO had more damage to the cell membrane than Zn(2+) did, which could be proven by the malondialdehyde content in Anabaena sp. cells. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 895-903, 2015.


Assuntos
Anabaena/efeitos dos fármacos , Quelantes/farmacologia , Substâncias Húmicas , Óxido de Zinco/toxicidade , Zinco/toxicidade , Animais , Membrana Celular/efeitos dos fármacos , Quelantes/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/toxicidade , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
15.
Biotechnol Lett ; 36(11): 2343-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25048229

RESUMO

Plant-specific BURP family proteins have a diverse subcellular localization with different functions. However, only limited studies have investigated the functions of their different domains. In the present study, the role of the N-terminal putative signal peptide in protein subcellular localization was investigated using a tobacco cell system. The results showed that SALI3-2 was present in vacuoles, whereas AtRD22 was directed to the apoplast. The N-terminal putative signal peptides of both proteins were confirmed to be the essential and critical domains for targeting the proteins to their destinations. We also demonstrate that the expression and accumulation of mGFP in tobacco cells was increased when mGFP was fused to the putative signal peptide of SALI3-2. The findings offer the potential application of this short peptide in protein production in plants.


Assuntos
Nicotiana/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Sinais Direcionadores de Proteínas/genética , Transporte Proteico/genética , Linhagem Celular , Espaço Intracelular/química , Espaço Intracelular/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/citologia , Plantas Geneticamente Modificadas/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Nicotiana/citologia , Nicotiana/metabolismo , Vacúolos/genética , Vacúolos/metabolismo
16.
Heliyon ; 10(2): e24088, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293534

RESUMO

Purpose: Malignant biliary obstruction (MBO) is common in patients with advanced malignant tumors, leading to poor prognosis and hindering antitumor therapy. The purpose of our study was to assess the survival outcomes for patients under therapy after percutaneous transhepatic biliary drainage (PTBD) and identify prognostic factors associated with survival in patients with MBO. Methods: From July 2010 to February 2021, 269 patients with MBO secondary to malignant tumor were divided into two groups (functional success and non-functional success). Survival time and prognostic factors were analyzed by Kaplan-Meier curves and the Cox model. Results: The overall median survival time after PTBD was 4.6 months (95 % IC:3.9-5.3). The 3- and 6-month survival rates were 68.0 % and 38.7 %, respectively. The median survival improved from 3.2 months to 8.4 months when the procedure achieved functional success. Multivariate analysis demonstrated that functionally successful drainage and antitumor treatment after PTBD were independent positive prognostic factors, but the total bilirubin after drainage and tumor size were independent negative predictive values. Conclusions: Functionally successful drainage could prolong survival time in patients with malignant biliary obstruction. Palliative care after drainage can prolong patient survival and improve their quality of life.

17.
Chemosphere ; 358: 142204, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704044

RESUMO

Bisphenol A (BPA) is a typical endocrine disruptor, which can be used as an industrial raw material for the synthesis of polycarbonate and epoxy resins, etc. Recently, BPA has appeared on the list of priority new pollutants for control in various countries and regions. In this study, phenolic resin waste was utilized as a multi-carbon precursor for the electrocatalytic cathode and loaded with cobalt/nitrogen (Co/N) on its surface to form qualitative two-dimensional carbon nano-flakes (Co/NC). The onset potentials, half-wave potentials, and limiting current densities of the nitrogen-doped composite carbon material Co/NC in oxygen saturated 0.5 mol H2SO4 were -0.08 V, -0.61 V, and -0.41 mA cm-2; and those of alkaline conditions were -0.65 V, -2.51 V, and -0.38 mA cm-2, and the corresponding indexes were improved compared with those of blank titanium electrodes, which indicated that the constructed nitrogen-doped composite carbon material Co/NC was superior in oxygen reduction ability. The catalysis by metallic cobalt as well as the N-hybridized active sites significantly improved the efficiency of electrocatalytic degradation of BPA. In the electro-Fenton system, the yield of hydrogen peroxide generated by cathodic reduction of oxygen was 4.012 mg L-1, which effectively promoted the activation of hydroxyl radicals. The removal rate of BPA was above 95% within 180 min. This work provides a new insight for the design and development of novel catalyst to degrade organic pollutants.


Assuntos
Compostos Benzidrílicos , Cobalto , Nitrogênio , Fenóis , Compostos Benzidrílicos/química , Fenóis/química , Cobalto/química , Catálise , Nitrogênio/química , Poluentes Químicos da Água/química , Eletrodos , Carbono/química , Peróxido de Hidrogênio/química , Técnicas Eletroquímicas/métodos , Disruptores Endócrinos/química
18.
Plant Physiol Biochem ; 206: 108126, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38147709

RESUMO

Heavy metal cadmium (Cd) hinders plants' growth and productivity by causing different morphological and physiological changes. Nanoparticles (NPs) are promising for raising plant yield and reducing Cd toxicity. Nonetheless, the fundamental mechanism of nanoparticle-interfered Cd toxicity in Brassica parachineses L. remains unknown. A novel ZnO nanoparticle (ZnO-NPs) was synthesized using a microalgae strain (Chlorella pyrenoidosa) through a green process and characterized by different standard parameters through TEM, EDX, and XRD. This study examines the effect of different concentrations of ZnO-NPs (50 and 100 mgL-1) in B. parachineses L. under Cd stress through ultra-high-performance liquid chromatography/high-resolution mass spectrometry-based untargeted metabolomics profiling. In the presence of Cd toxicity, foliar spraying with ZnO-NPs raised Cu, Fe, Zn, and Mg levels in the roots and/or leaves, improved seedling development, as demonstrated by increased plant height, root length, and shoot and root fresh weight. Furthermore, the ZnO-NPs significantly enhanced the photosynthetic pigments and changed the antioxidant activities of the Cd-treated plants. Based on a metabolomics analysis, 481 untargeted metabolites were accumulated in leaves under normal and Cd-stressed conditions. These metabolites were highly enriched in producing organic acids, amino acids, glycosides, flavonoids, nucleic acids, and vitamin biosynthesis. Surprisingly, ZnO-NPs restored approximately 60% of Cd stress metabolites to normal leaf levels. Our findings suggest that green synthesized ZnO-NPs can balance ions' absorption, modulate the antioxidant activities, and restore more metabolites associated with plant growth to their normal levels under Cd stress. It can be applied as a plant growth regulator to alleviate heavy metal toxicity and improve crop yield in heavy metal-contaminated regions.


Assuntos
Chlorella , Metais Pesados , Nanopartículas , Poluentes do Solo , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Cádmio/análise , Antioxidantes , Chlorella/metabolismo , Nanopartículas/química , Metais Pesados/toxicidade , Poluentes do Solo/metabolismo
19.
Pediatr Neurol ; 153: 137-143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382246

RESUMO

BACKGROUND: Currently, there is no universally accepted standard treatment for ocular myasthenia gravis (OMG) in children. We aimed to investigate the possible proper regimens and timing of treatment for pediatric OMG cases based on the clinical manifestations: OMG with ptosis only and OMG with other features. METHODS: One hundred and forty two OMG cases attended at the Department of Pediatrics, Xiangya Hospital, Central South University, from 2010 to 2019 were included, and information from medical records was reviewed and recorded. Comparisons of clinical characteristics between patients with OMG with ptosis only and patients with OMG with other features as well as between patients treated with glucocorticoid (GC) within or after six months from disease onset were performed. RESULTS: OMG with other features constituted about 54.9% of the cases, and 66.2% of the patients achieved optimal outcome. Patients with OMG with ptosis only responded to pyridostigmine alone more than patients with OMG with other features who required several therapies (P < 0.001). Patients with OMG with ptosis only had a larger proportion of optimal outcome than the patients with OMG with other features (P = 0.002), and the difference remained significant even when the individual outcome groups were compared (P < 0.001). Patients who received GC within six months had a greater proportion of optimal outcome than those who received it after six months (P < 0.001). CONCLUSIONS: Although OMG with other features is a more common subtype of OMG, it is also more severe than OMG with ptosis only. An earlier addition of GC leads to optimal outcome.


Assuntos
Blefaroptose , Miastenia Gravis , Humanos , Criança , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamento farmacológico , Blefaroptose/tratamento farmacológico , Blefaroptose/etiologia , Brometo de Piridostigmina/uso terapêutico , Glucocorticoides/uso terapêutico , Estudos Retrospectivos
20.
Biotechnol Adv ; 73: 108380, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38759845

RESUMO

Carbon source is crucial for the cell growth and metabolism in microorganisms, and its utilization significantly affects the synthesis efficiency of target products in microbial cell factories. Compared with a single carbon source, co-utilizing carbon sources provide an alternative approach to optimize the utilization of different carbon sources for efficient biosynthesis of many chemicals with higher titer/yield/productivity. However, the efficiency of bioproduction is significantly limited by the sequential utilization of a preferred carbon source and secondary carbon sources, attributed to carbon catabolite repression (CCR). This review aimed to introduce the mechanisms of CCR and further focus on the summary of the strategies for co-utilization of carbon sources, including alleviation of CCR, engineering of the transport and metabolism of secondary carbon sources, compulsive co-utilization in single culture, co-utilization of carbon sources via co-culture, and evolutionary approaches. The findings of representative studies with a significant improvement in the bioproduction of chemicals via the co-utilization of carbon sources were discussed in this review. It suggested that by combining rational metabolic engineering and irrational evolutionary approaches, co-utilizing carbon sources can significantly contribute to the bioproduction of chemicals.


Assuntos
Carbono , Engenharia Metabólica , Carbono/metabolismo , Repressão Catabólica , Bactérias/metabolismo
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