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1.
Plant Cell ; 35(5): 1474-1495, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36781400

RESUMO

The major antioxidant L-ascorbic acid (AsA) plays important roles in plant growth, development, and stress responses. However, the importance of AsA concentration and the regulation of AsA metabolism in plant reproduction remain unclear. In Arabidopsis (Arabidopsis thaliana) anthers, the tapetum monolayer undergoes cell differentiation to support pollen development. Here, we report that a transcription factor, DEFECTIVE IN TAPETAL DEVELOPMENT AND FUNCTION 1 (TDF1), inhibits tapetal cell division leading to cell differentiation. We identified SKEWED5-SIMILAR 18 (SKS18) as a downstream target of TDF1. Enzymatic assays showed that SKS18, annotated as a multicopper oxidase-like protein, has ascorbate oxidase activity, leading to AsA oxidation. We also show that VITAMIN C DEFECTIVE1 (VTC1), an AsA biosynthetic enzyme, is negatively controlled by TDF1 to maintain proper AsA contents. Consistently, either knockout of SKS18 or VTC1 overexpression raised AsA concentrations, resulting in extra tapetal cells, while SKS18 overexpression in tdf1 or the vtc1-3 tdf1 double mutant mitigated their defective tapetum. We observed that high AsA concentrations caused lower accumulation of reactive oxygen species (ROS) in tapetal cells. Overexpression of ROS scavenging genes in tapetum restored excess cell divisions. Thus, our findings demonstrate that TDF1-regulated AsA balances cell division and cell differentiation in the tapetum through governing ROS homeostasis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Ascórbico , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Divisão Celular , Diferenciação Celular/genética , Homeostase , Regulação da Expressão Gênica de Plantas
2.
Cancer Causes Control ; 35(1): 55-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37540479

RESUMO

BACKGROUND: The use of antidepressants has increased over the years, but the relationship between antidepressant use and the risk of breast cancer is not uniform because of confounding factors. We aimed to assess the effect of antidepressants on breast cancer risk using a two-sample Mendelian randomization (MR) approach.stet METHODS: Secondary data analysis was performed on pooled data from genome-wide association studies based on single-nucleotide polymorphisms that were highly correlated with antidepressants, SSRI drugs, and serotonin and prolactin levels were selected as instrumental variables to evaluate the association between antidepressants and SSRI drugs and prolactin levels with breast cancer and ER+/ER- breast cancer. We then performed a test of the hypothesis that SSRI drugs elevate prolactin concentrations. We performed two-sample Mendelian randomization analyses using inverse variance weighting, MR-Egger regression, and weighted median methods, respectively. RESULTS: There was no significant risk association between antidepressant and SSRI use and the development of breast cancer, ER-positive or ER-negative breast cancer (P > 0.05), and serotonin concentration was not associated with breast cancer risk (P > 0.05). There was a positive causal relationship between prolactin levels and breast cancer (IVW, P = 0.02, OR = 1.058) and ER-positive breast cancer (Weighted median, P = 0.043, OR = 1.141; IVW, P = 0.009, OR = 1.125). Results in SSRI medication and prolactin levels showed no association between SSRI analogs and prolactin levels (P > 0.05). CONCLUSION: Large MR analysis showed that antidepressants as well as SSRI drugs were not associated with breast cancer risk and the SSRI-prolactin-breast cancer hypothesis did not hold in our analysis.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Prolactina , Serotonina , Polimorfismo de Nucleotídeo Único , Antidepressivos/efeitos adversos
3.
Gynecol Oncol ; 182: 15-23, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38246042

RESUMO

BACKGROUND: Several abstract studies have demonstrated that metformin may be beneficial for preventing and treating endometrial cancer (EC), while the results have been inconsistent and inconclusive. This systematic review and meta-analysis aimed to investigate the association between metformin use and the incidence and mortality of endometrial cancer in diabetic patients. METHODS: A systematic literature search was performed in Pubmed, EMBASE, Web of Science, Cochrane Library, SinoMed, CNKI, Wanfang Data, and VIP from inception to November 2022. The outcome measures were hazard ratios (HRs) comparing the EC incidence and mortality in patients with type 2 diabetes mellitus (T2DM) on metformin and non-metformin. A random or fixed-effects model was applied for data analysis, and subgroup analysis was performed to look for factors of heterogeneity. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessed the evidence's certainty. RESULTS: Eleven studies reported data on EC incidence. The pooled results suggested that the use of metformin was associated with a significantly higher incidence of EC (HR = 1.17, 95% CI 1.09-1.26, P < 0.0001). Further, seventeen studies were included for survival analysis. The pooled data showed that metformin could significantly decrease all-cause mortality (HR = 0.62, 95% CI 0.52-0.74, P < 0.00001) and endometrial cancer-specific mortality (HR = 0.95, 95% CI 0.90, 1.00, P = 0.03). Finally, we noted that metformin was associated with significantly improving the progression-free survival (PFS) of EC patients with T2DM (HR = 0.55, 95% CI 0.44, 0.68, P < 0.00001). CONCLUSIONS: This meta-analysis did not prove that metformin was beneficial for preventing EC. However, metformin could reduce their mortality risk and prolong the progression-free survival time of EC patients with T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Neoplasias do Endométrio , Hipoglicemiantes , Metformina , Metformina/uso terapêutico , Humanos , Feminino , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Hipoglicemiantes/uso terapêutico , Prognóstico , Incidência
4.
Future Oncol ; 20(18): 1267-1274, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38639577

RESUMO

Objective: Observational studies showed that Type 2 diabetes increased the risk of breast cancer, and vice versa. However, it is uncertain whether the link is causal or just due to confounding factors. Using bidirectional Mendelian randomization analysis, we assessed the bidirectional causal relationship from a genetic level. Methods: Large genome-wide association studies yielded summary-level data for Type 2 diabetes and breast cancer. Results: Genetically predicted Type 2 diabetes presented no statistically significant association with overall breast cancer or its subtypes. Similarly, genetically predicted overall breast cancer or its subtypes had no causal effect on Type 2 diabetes. Sensitivity analyses yielded similar results. Conclusion: Our bidirectional Mendelian randomization studies revealed no causal links between Type 2 diabetes and breast cancer.


[Box: see text].


Assuntos
Neoplasias da Mama , Diabetes Mellitus Tipo 2 , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/etiologia , Neoplasias da Mama/epidemiologia , Feminino , Fatores de Risco , Causalidade
5.
Environ Res ; 212(Pt B): 113340, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35452671

RESUMO

Sulfate radical (SO4•-) based advanced oxidation processes (SR-AOPs) is a very important chemical oxidation technology for the degradation of recalcitrant organic pollutants in water and has been well developed. Recently, transition metals or their oxides-modified biochar has been widely used as the catalyst to catalyze peroxymonosulfate (PMS) and peroxydisulfate (PS) in SR-AOPs due to their outstanding properties (e.g., large surface area, high stability, abound catalytic sites, and diversity of material design, etc.). These composite materials not only combine the respective beneficial characteristics of biochar and transition metals (or their oxides) but also often present synergistic effects between the components. In this review, we present the synthesis of different types of transition metal (or metal oxides)/biochar-based catalysts and their application in SR-AOPs. The catalytic mechanism, including the generation process of free radicals and other reaction pathways on the surface of the catalyst were also carefully discussed. Particular attention has been paid to the synergistic effects between the components that result in enhanced catalytic performance. At the end of this review, the future development prospects of this technology are proposed.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Oxirredução , Óxidos , Sulfatos , Poluentes Químicos da Água/química
6.
J Clin Pharm Ther ; 47(9): 1402-1408, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35488787

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Propofol is widely used in painless gastroscopy. However, sedation with propofol alone might increase the risk of respiratory and circulatory complications. This randomized clinical study compares the efficacy and safety of esketamine or dezocine combined with intravenous (IV) propofol in patients undergoing gastroscopy. METHODS: A total of 102 patients were enrolled in this study and randomized into two groups. All patients were adults aged 18-64 years who underwent upper gastrointestinal gastroscopy. Patients were randomly assigned to two groups to receive esketamine (0.3 mg/kg) combined with propofol (group E) or dezocine (0.05 mg/kg) combined with propofol (group D). In both groups, the drugs were administered intravenously. The primary outcome was the dose of propofol which provided a satisfactory sedative effect, both to the endoscopist and the patients. Secondary outcomes included recovery time, side effects (such as hypotension, nausea and vomiting and agitation), and the number of adverse circulatory and respiratory events. RESULTS: Data of 83 patients were analysed in the present study. Dosage of propofol required in group E (1.44 mg/kg ± 0.67 mg/kg) was significantly lower compared with that in group D (2.12 mg/kg ± 0.37 mg/kg) (p < 0.0001). There was no statistically significant difference in recovery time, side effects, and the frequency of sedation-related adverse events between the two groups. WHAT IS NEW AND CONCLUSION: The study indicates that intravenous injection of propofol and esmketamine is more effective for gastroscopy. Use of esketamine reduces the total amount of propofol required in ASA I-II patients undergoing gastroscopy compared with single use of dezocine. It also provides more stable hemodynamics, without affecting the recovery time and side effects such as respiratory and circulatory adverse events. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trial Registry (www.chictr.org.cn; registration number: ChiCTR2100051814) on 05/10/2021.


Assuntos
Propofol , Adulto , Compostos Bicíclicos Heterocíclicos com Pontes , Gastroscopia/efeitos adversos , Humanos , Hipnóticos e Sedativos/efeitos adversos , Ketamina , Propofol/efeitos adversos , Tetra-Hidronaftalenos
7.
Molecules ; 27(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35807441

RESUMO

In this study, we investigated and compared the oil yield, physicochemical properties, fatty acid composition, nutrient content, and antioxidant ability of Xanthoceras sorbifolia Bunge (X. sorbifolia) kernel oils obtained by cold-pressing (CP), hexane extraction (HE), aqueous enzymatic extraction (AEE), and supercritical fluid extraction (SFE). The results indicated that X. sorbifolia oil contained a high percentage of monounsaturated fatty acids (49.31-50.38%), especially oleic acid (30.73-30.98%) and nervonic acid (2.73-3.09%) and that the extraction methods had little effect on the composition and content of fatty acids. X. sorbifolia oil is an excellent source of nervonic acid. Additionally, the HE method resulted in the highest oil yield (98.04%), oxidation stability index (9.20 h), tocopherol content (530.15 mg/kg) and sterol content (2104.07 mg/kg). The DPPH scavenging activity rates of the oil produced by SFE was the highest. Considering the health and nutritional value of oils, HE is a promising method for X. sorbifolia oil processing. According to multiple linear regression analysis, the antioxidant capacity of the oil was negatively correlated with sterol and stearic acid content and positively correlated with linoleic acid, arachidic acid and polyunsaturated fatty acid content. This information is important for improving the nutritional value and industrial production of X. sorbifolia.


Assuntos
Antioxidantes , Sapindaceae , Antioxidantes/análise , Ácidos Graxos/análise , Óleos de Plantas/química , Sapindaceae/química , Sementes/química , Esteróis/análise
8.
Molecules ; 27(1)2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35011504

RESUMO

Uropathogenic Escherichia coli (UPEC) is the most common pathogenic bacteria associated with urinary tract infection (UTI). UPEC can cause UTI by adhering to and invading uroepithelial cells. Fimbriae is the most important virulence factor of UPEC, and a potentially promising target in developing novel antibacterial treatments. In this study, the antibacterial properties and effects of the compound dictamnine, extracted from the traditional Chinese medicine Cortex Dictamni, on the bacterial morphology, cell adhesion, and invasion of UPEC were studied. Dictamnine exhibited no obvious antibacterial activity against UPEC, but significantly impeded the ability of UPEC to adhere to and invade uroepithelial cells. RT-qPCR analysis showed that treatment downregulated the expression of type 1 fimbriae, P fimbriae, and curli fimbriae adhesion genes, and also downregulated adhesion-related receptor genes of uroepithelial cells. Transmission electron microscopy showed that dictamnine destroyed the structure of the fimbriae and the surface of the bacteria became smooth. These results suggest that dictamnine may help to prevent UTI by simultaneously targeting UPEC fimbriae and urothelial adhesin receptors, and may have a potential use as a new anti-UPEC drug.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Quinolinas/farmacologia , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/metabolismo , Urotélio/microbiologia , Linhagem Celular , Infecções por Escherichia coli/microbiologia , Humanos , Infecções Urinárias/microbiologia , Urotélio/metabolismo
9.
Infect Immun ; 89(3)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33318141

RESUMO

Streptococcus suis serotype 2 is a crucial pathogenic cause of bacterial meningitis, a life-threatening disease with neurological sequelae and high rates of mortality. Inflammation triggered by S. suis infection must be precisely regulated to prevent further tissue damage. As a glucocorticoid anti-inflammatory mediator, annexin A1 (AnxA1) mainly acts through formyl peptide receptor 2 (Fpr2) to alleviate inflammation in the peripheral system. In this study, we evaluated the roles of AnxA1 and Fpr2 in a mouse model of S. suis meningitis created via intracisternal infection in Fpr2-deficient (Fpr2-/-) and wild-type (WT) mice. We revealed that Fpr2-/- mice were highly susceptible to S. suis meningitis, displaying increased inflammatory cytokine levels, bacterial dissemination, and neutrophil migration compared with WT mice. Additionally, AnxA1 exerted anti-inflammatory effects through Fpr2, such as attenuation of leukocyte infiltration, inflammatory mediator production, and astrocyte or microglial activation in the brain. Importantly, we found that the antimigratory function of AnxA1 decreases neutrophil adherence to the endothelium through Fpr2. Finally, an in vitro study revealed that AnxA1 potentially suppresses interleukin-6 (IL-6) expression through the Fpr2/p38/COX-2 pathway. These data demonstrated that Fpr2 is an anti-inflammatory receptor that regulates neutrophil migration in mice with S. suis meningitis and identified AnxA1 as a potential therapeutic option.


Assuntos
Anexina A1/metabolismo , Movimento Celular/efeitos dos fármacos , Interleucina-6/genética , Interleucina-6/metabolismo , Meningite/genética , Meningite/metabolismo , Streptococcus suis/genética , Streptococcus suis/patogenicidade , Animais , Modelos Animais de Doenças , Inflamação/metabolismo , Masculino , Meningite/patologia , Camundongos , Neutrófilos/metabolismo , Receptores de Formil Peptídeo/metabolismo
10.
Langmuir ; 37(33): 10020-10028, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34375117

RESUMO

Most marine antifouling coatings rely on the release of toxic biocides to prevent fouling organisms from attaching, causing environmental pollution. This work proposes a biocide-free environmentally friendly marine antifouling strategy. Slippery-liquid-infused electrostatic flocking surfaces (S-EFSs) were prepared by combining electrostatic flocking and slippery liquid infusion. They exhibited complete mussel resistance after comparing adhesion to the surface of different materials in the laboratory. In addition, the unique surface morphology including lubricant was found to be crucial to their antifouling performance. Real-time polymerase chain reaction showed that different surfaces significantly affected the gene-expression levels of the mussels' foot proteins, where higher levels on S-EFSs meant that the mussels tried to secrete more proteins but they failed to adhere. Moreover, a 148-day field test showed that S-EFSs can resist not only mussels but also tubeworms, tunicates, and barnacles, and the total fouling area decreased by more than 50% compared to control samples. Notably, the maturity of electrostatic flocking technology and the simplicity of the modification steps used endow this strategy with the potential to significantly reduce the economic loss caused by marine biofouling in practical applications.


Assuntos
Incrustação Biológica , Desinfetantes , Thoracica , Animais , Incrustação Biológica/prevenção & controle , Desinfetantes/toxicidade , Eletricidade Estática , Propriedades de Superfície
11.
Infect Immun ; 88(4)2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-31988176

RESUMO

Streptococcus suis is an emerging zoonotic agent that causes streptococcal toxic shock-like syndrome (STSLS) and meningitis in humans, with high mortality and morbidity. The pathogenesis of both STSLS and central nervous system (CNS) infections caused by S. suis is not well understood. TRIM32, a member of the tripartite motif (TRIM) protein family, has been reported to regulate host inflammatory responses. In this study, we showed that TRIM32 deficiency significantly reduced the level of bacteremia and the production of proinflammatory cytokines following severe S. suis infection, protecting infected mice from STSLS. The influence of TRIM32 gene deletion on a range of processes known to be involved in S. suis meningitis was also examined. Both levels of bacterial loads and indications of brain hemorrhage were reduced in infected Trim32-/- mice compared with infected wild-type (WT) controls. We also found that TRIM32 deficiency increased the permeability of the blood-brain barrier (BBB) and the recruitment of inflammatory monocytes during the early course of S. suis infection, potentially limiting the development of S. suis meningitis. Our results suggest that TRIM32 sensitizes S. suis-induced infection via innate immune response regulation.


Assuntos
Interações Hospedeiro-Patógeno , Meningites Bacterianas/fisiopatologia , Choque Séptico/fisiopatologia , Streptococcus suis/crescimento & desenvolvimento , Ubiquitina-Proteína Ligases/metabolismo , Animais , Modelos Animais de Doenças , Suscetibilidade a Doenças , Imunidade Inata , Meningites Bacterianas/imunologia , Camundongos , Camundongos Knockout , Choque Séptico/imunologia , Ubiquitina-Proteína Ligases/deficiência
12.
Microb Pathog ; 134: 103563, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175974

RESUMO

Tuberculosis (TB) is one of the most prevalent pulmonary diseases caused by Mycobacterium tuberculosis (Mtb). MiRNAs (miRNAs) participate in TB progression by modulating the host-pathogen interaction. Bioinformatics advancements provide basis for exploring novel immunoregulatory miRNAs and their performance as diagnostic biomarkers. Gene and miRNA expression datasets, GSE29190 and GSE54992, were downloaded from Gene Expression Omnibus (GEO) database. Based on fold changes and statistical significance, a total of 7463 differentially expressed mRNAs (DE-mRNAs) and 38 differentially expressed miRNAs (DE-miRNAs) were screened. Function annotation and protein-protein interaction (PPI) network were constructed to reveal underlying mechanisms of TB pathogenesis. Functional annotation identified the MAPK signalling pathway and leukocyte migration as the top enriched processes. The PPI and MGIP networks indicated that chemokine ligands like CXCL1/CXCL2 and receptors, like CCR7 were important down-regulated genes, implying that a protective mechanism against overdue inflammation induced cell death. MiRNA-gene-immune processes (MGIP) network enriched 7 deregulated miRNAs, and their expression was further examined with quantitative real-time PCR (qRT-PCR), in PBMC samples of 20 active TB patients and 20 healthy donors. The diagnostic performance was evaluated with ROC curves. MiR-892b; miR-199b-5p and miR-582-5p were significantly deregulated in TB patients, compared with healthy participants. The best overall performance was from miR-892b, with an area under curve (AUC) of 0.77, 55% sensitivity and 90% specificity. AUC of miR-199b-5p and miR-582-5p were 0.71 and 0.70, respectively. MiR-892b, miR-199b-5p and miR-582-5p could be considered promising novel diagnostic biomarkers for active tuberculosis.


Assuntos
Biomarcadores/sangue , Biologia Computacional/métodos , Fatores Imunológicos , MicroRNAs/imunologia , Tuberculose/diagnóstico , Tuberculose/imunologia , Morte Celular , Quimiocina CXCL1/metabolismo , Quimiocina CXCL2/metabolismo , China , Regulação para Baixo , Expressão Gênica , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno/imunologia , Humanos , Leucócitos Mononucleares/microbiologia , MicroRNAs/genética , Mycobacterium tuberculosis/genética , Receptores CCR7/metabolismo , Sensibilidade e Especificidade
13.
BMC Infect Dis ; 19(1): 289, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30922257

RESUMO

BACKGROUND: Purulent meningitis (PM) is a serious life-threatening infection of the central nervous system (CNS) by bacteria or fungi and associated with high mortality and high incidence of CNS sequelae in children. However, the conventional cerebrospinal fluid (CSF) culture method is time-consuming and has a low sensitivity. METHODS: Our study developed a real-time PCR-based purulent meningitis-TaqMan array card (PM-TAC) that targeted 21 PM-related pathogens and could produce results within 3 h. Primers and probes were adapted from published sources possibly. The performance of them were evaluated and optimized and then they were spotted on TAC. RESULTS: The PM-TAC showed a sensitivity and specificity of 95 and 96%, respectively. For all of the 21 targeted pathogens, the PM-TAC assay had a LOD ranging from 5 copies/reaction to 100 copies/reaction, an intra-assay variation of 0.07-4.45%, and an inter-assay variation of 0.11-6.81%. Of the 15 CSF samples collected from patients with PM after empiric antibiotic therapies, the positive rate was 53.3% (8/15) for our PM-TAC assay but was only 13.3% (2/15) for the CSF culture method. Of the 17 CSF samples showing negative CSF culture, the PM-TAC assay identified a case of Neisseria meningitidis infection. Furthermore, all of the 10 CSF samples from patients without CNS infection showed negative for the PM-TAC assay. CONCLUSIONS: Our PM-TAC assay also demonstrated that the pathogen loads in the CSF samples correlated with the severity of PM. Thus, the PM-TAC may be helpful to improve the prognosis of PM and clinical outcomes from antibiotic therapies.


Assuntos
Bactérias/genética , Fungos/genética , Meningites Bacterianas/microbiologia , Meningite Fúngica/microbiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Líquido Cefalorraquidiano/microbiologia , Criança , Primers do DNA/genética , Feminino , Fungos/isolamento & purificação , Fungos/patogenicidade , Humanos , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Meningite Fúngica/líquido cefalorraquidiano , Neisseria meningitidis/genética , Neisseria meningitidis/isolamento & purificação , Sensibilidade e Especificidade
14.
Dig Dis Sci ; 64(11): 3357, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31630342

RESUMO

The Editor-in-Chief has retracted this article [1] because Figure 8 overlaps with Figure 6b of [2] and Figure 6 overlaps with Figure 3 of [3] and Figure 3 of [4].

15.
Ecotoxicol Environ Saf ; 184: 109612, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476450

RESUMO

Microplastics (MPs) are small plastic pieces with size less than 5 mm that have entered and polluted the environment. While many investigations including several critical reviews on MPs in the environment have been conducted, most of them are focused on their occurrences in marine environment. Current understanding on the occurrences, behaviors, and impacts of MPs in the terrestrial environment is far from complete. A systematic review of the literature was thus conducted to promote the research on MPs in the environment. This work is designed to provide a comprehensive overview that summarizes current knowledge and research findings on environmental occurrences, fate and transport, and impacts of MPs. In addition to discussing the occurrences, characteristics, and sources of MPs in the ocean, freshwater, sediments, soils, and atmosphere, the review also summarizes both the experimental and modeling data of the environmental fate and transport of MPs. Research findings on the toxic effects, bioaccumulation, and bioavailability of MPs in the environment are also covered in this critical review. Future perspectives are discussed as well.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Poluição Ambiental/análise , Microplásticos/análise , Disponibilidade Biológica , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Poluição Ambiental/efeitos adversos , Microplásticos/metabolismo , Microplásticos/toxicidade , Modelos Teóricos
16.
Crit Rev Environ Sci Technol ; 49(4): 318-356, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34121831

RESUMO

Alginate-based composites have been extensively studied for applications in energy and environmental sectors due to their biocompatible, nontoxic, and cost-effective properties. This review is designed to provide an overview of the synthesis and application of alginate-based composites. In addition to an overview of current understanding of alginate biopolymer, gelation process, and cross-linking mechanisms, this work focuses on adsorption mechanisms and performance of different alginate-based composites for the removal of various pollutants including dyes, heavy metals, and antibiotics in water and wastewater. While encapsulation in alginate gel beads confers protective benefits to engineered nanoparticles, carbonaceous materials, cells and microbes, alginate-based composites typically exhibit enhanced adsorption performance. The physical and chemical properties of alginate-based composites determine the effectiveness under different application conditions. A series of alginate-based composites and their physicochemical and sorptive properties have been summarized. This critical review not only summarizes recent advances in alginate-based composites but also presents a perspective of future work for their environmental applications.

17.
J Biol Chem ; 291(33): 17122-32, 2016 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-27342778

RESUMO

Streptococcus suis serotype 2 (S. suis 2)-induced sepsis and meningitis are often accompanied by bacteremia. The evasion of polymorphonuclear leukocyte-mediated phagocytic clearance is central to the establishment of bacteremia caused by S. suis 2 and is facilitated by the ability of factor H (FH)-binding protein (Fhb) to bind FH on the bacterial surface, thereby impeding alternative pathway complement activation and phagocytic clearance. Here, C3b/C3d was found to bind to Fhb, along with FH, forming a large immune complex. The formation of this immune complex was mediated by domain II of Fhb via electrostatic and hydrophobic interactions, which, to our knowledge, is a new type of interaction. Interestingly, Fhb was found to be associated with the cell envelope and also present in the culture supernatant, where secreted Fhb inhibited complement activation via interactions with domain II, thereby enhancing antiphagocytic clearance by polymorphonuclear leukocytes. Thus, Fhb is a multifunctional bacterial protein, which binds host complement component C3 as well as FH and interferes with innate immune recognition in a secret protein manner. S. suis 2 therefore appears to have developed a new strategy to combat host innate immunity and enhance survival in host blood.


Assuntos
Proteínas de Bactérias/imunologia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Infecções Estreptocócicas/imunologia , Streptococcus suis/fisiologia , Streptococcus suis/patogenicidade , Proteínas de Bactérias/genética , Complemento C3b/imunologia , Complemento C3d/imunologia , Fator H do Complemento/imunologia , Humanos , Leucócitos/imunologia , Leucócitos/microbiologia , Infecções Estreptocócicas/genética
18.
J Biol Chem ; 290(31): 19081-92, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26085092

RESUMO

Streptococcus suis serotype 2 (Ss2) is an important swine and human zoonotic pathogen. In the present study, we identified a novel secreted immunogenic protein, SsTGase, containing a highly conserved eukaryotic-like transglutaminase (TGase) domain at the N terminus. We found that inactivation of SsTGase significantly reduced the virulence of Ss2 in a pig infection model and impaired its antiphagocytosis in human blood. We further solved the crystal structure of the N-terminal portion of the protein in homodimer form at 2.1 Å. Structure-based mutagenesis and biochemical studies suggested that disruption of the homodimer directly resulted in the loss of its TGase activity and antiphagocytic ability. Characterization of SsTGase as a novel virulence factor of Ss2 by acting as a TGase would be beneficial for developing new therapeutic agents against Ss2 infections.


Assuntos
Proteínas de Bactérias/química , Streptococcus suis/enzimologia , Transglutaminases/química , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/fisiologia , Domínio Catalítico , Sequência Conservada , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Fagocitose , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Sus scrofa , Transglutaminases/fisiologia , Fatores de Virulência
19.
J Infect Dis ; 210(1): 35-45, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24446521

RESUMO

Streptococcus suis serotype 2 (S. suis 2) is a highly invasive pathogen in pigs and humans that can cause severe systemic infection. Sepsis and meningitis are the most common clinical manifestations of S. suis 2 infection. However, the mechanisms of S. suis 2 surviving in human blood remains unclear, so to identify novel virulence factors in evasion of polymorphonuclear leukocyte (PMN)-mediated innate immunity play important roles in developing therapies against S. suis 2 infection. Here, we found that S. suis 2 can escape phagocytic clearance by adenosine synthesis in blood. Through bioinformatics-based analyses we identified a cell wall-anchored protein harbors a 5'-nucleotidase signature sequence and evidence strongly indicated that it can convert adenosine monophosphate (AMP) to adenosine. It was designated as Ssads (the adenosine synthase of S. suis 2). Furthermore, we found that Ssads could impair PMN's defense against S. suis 2 with decreasing of oxidative activity and degranulation of PMNs in human blood via A2a receptors. Additionally, this enzyme-deficient mutant was found to have diminished virulence in the piglet infection model. Taken together, these results indicate that Ssads play an important role in S. suis 2 escaping human innate immunity in the context of inhibiting PMN's activity by synthesis of adenosine.


Assuntos
Adenosina/biossíntese , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Neutrófilos/imunologia , Neutrófilos/microbiologia , Streptococcus suis/enzimologia , Streptococcus suis/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Imunidade Inata , Fagocitose , Suínos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
20.
Tumour Biol ; 35(2): 1193-201, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24022665

RESUMO

Notch has recently been shown to promote epithelial-to-mesenchymal transition (EMT) by involving in the EMT process that occurs during tumor progression and converts polarized epithelial cells into motile, invasive cells. However, it is still unclear whether the Notch signaling pathway is associated with the regulation of EMT in esophageal carcinoma. The present study explored Notch-1-mediated esophageal carcinoma EC-9706 cell invasion and metastasis by inducing epithelial­mesenchymal transition through Snail. The results demonstrated that the inhibition of Notch-1 expression in the esophageal carcinoma cell line EC-9706 could suppress the occurrence of EMT and at the same time could decrease the invasion and metastasis ability of the EC-9706 cells, indicative of its role in EMT. Snail is a transcriptional repressor of E-cadherin. We found that with the inhibition of Notch-1 expression in the esophageal carcinoma cell line EC-9706, the expression of Snail also decreased. Mechanistic studies showed that the up-expression of Snail in the EC-9706 cells restored the suppression of EMT regulated by Notch-1 inhibition, suggesting the role of Snail in Notch-1-mediated EMT. At the same time, the up-expression of Snail in the EC-9706 cells could also rescue the invasion and metastasis ability inhibited by Notch-1 siRNA. Taken together, our results had revealed that Notch-1 could participate in the invasion and metastasis of esophageal carcinoma through EMT via Snail. This study indicated that Notch-1 might be a useful target for esophageal carcinoma prevention and therapy.


Assuntos
Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/genética , Metástase Neoplásica/genética , Receptor Notch1/genética , Fatores de Transcrição/metabolismo , Animais , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Células NIH 3T3 , Invasividade Neoplásica/genética , Metástase Neoplásica/patologia , Ligação Proteica , RNA Interferente Pequeno , Receptor Notch1/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética
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