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1.
Cell Res ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047269

RESUMO

The majority of circular RNAs (circRNAs) spliced from coding genes contain open reading frames (ORFs) and thus, have protein coding potential. However, it remains unknown what regulates the biogenesis of these ORF-containing circRNAs, whether they are actually translated into proteins and what functions they play in specific physiological contexts. Here, we report that a large number of circRNAs are synthesized with increasing abundance when late pachytene spermatocytes develop into round and then elongating spermatids during murine spermatogenesis. For a subset of circRNAs, the back splicing appears to occur mostly at m6A-enriched sites, which are usually located around the start and stop codons in linear mRNAs. Consequently, approximately a half of these male germ cell circRNAs contain large ORFs with m6A-modified start codons in their junctions, features that have been recently shown to be associated with protein-coding potential. Hundreds of peptides encoded by the junction sequences of these circRNAs were detected using liquid chromatography coupled with mass spectrometry, suggesting that these circRNAs can indeed be translated into proteins in both developing (spermatocytes and spermatids) and mature (spermatozoa) male germ cells. The present study discovered not only a novel role of m6A in the biogenesis of coding circRNAs, but also a potential mechanism to ensure stable and long-lasting protein production in the absence of linear mRNAs, i.e., through production of circRNAs containing large ORFs and m6A-modified start codons in junction sequences.

2.
Microbiologyopen ; : e966, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743595

RESUMO

A novel piezophilic alphaproteobacterium, strain D4M1T , was isolated from deep seawater of the Mariana Trench. 16S rRNA gene analysis showed that strain D4M1T was most closely related to Oceanicella actignis PRQ-67T (94.2%), Oceanibium sediminis O448T (94.2%), and Thioclava electrotropha ElOx9T (94.1%). Phylogenetic analyses based on both 16S rRNA gene and genome sequences showed that strain D4M1T formed an independent monophyletic branch paralleled with the genus Oceanicella in the family Rhodobacteraceae. Cells were Gram-stain-negative, aerobic short rods, and grew optimally at 37°C, pH 6.5, and 3.0% (w/v) NaCl. Strain D4M1T was piezophilic with the optimum pressure of 10 MPa. The principal fatty acids were C18:1 ω7c/C18:1 ω6c and C16:0 , major respiratory quinone was ubiquinone-10, and predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, and an unidentified aminophospholipid. The complete genome contained 5,468,583-bp with a G + C content of 70.2 mol% and contained 4,855 protein-coding genes and 78 RNA genes. Genomic analysis revealed abundant clues on bacterial high-pressure adaptation and piezophilic lifestyle. The combined evidence shows that strain D4M1T represents a novel species of a novel genus in the family Rhodobacteraceae, for which the name Paraoceanicella profunda gen. nov., sp. nov. is proposed (type strain D4M1T  = MCCC 1K03820T  = KCTC 72285T ).

3.
Injury ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31676073

RESUMO

INTRODUCTION: Treatment of comminuted patella fractures with tension band has resulted in impaired functional outcomes because the relationship between tension band and the tendons is always underestimated. We developed a modified enlacement (ME) technique to better place the tension-band under the quadriceps and patellar tendons and close to the patella. The study aimed to compare the ME with conventional enlacement (CE) technique regarding recovery of knee function. PATIENTS AND METHODS: 51 patients with comminuted patella fractures operated between January 2012 and December 2016 were reviewed retrospectively. 22 patients in the ME group (9 males and 13 females) with a mean age of 51.3 years, 29 patients in the CE group (16 males and 13 females) with a mean age of 47.1 years. ROM was measured at postoperative intervals of 1, 2, 4, 12, and 48 weeks; Knee function was evaluated using the Rasmussen scores at 4, 12, and 48 weeks postoperative. RESULTS: There was no difference (P = 0.082) regarding the fracture healing time between the two groups. Patients with the ME technique had clinically and statistically significantly higher ROM recovery throughout the study period (P < 0.001) with an earlier recovery. The Rasmussen scores also demonstrated significant improvements in patients with ME technique than CE group at all time-points (P < 0.05). Three patients in the CE group had migration of K-wires, with no migration observed in the ME group. CONCLUSION: The ME technique enables improved clinical outcomes and functional performance for the treatment of comminuted patella fractures.

4.
Methods Inf Med ; 58(2-03): 94-106, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31514210

RESUMO

BACKGROUND: Radiology reports are a permanent record of patient's health information often used in clinical practice and research. Reading radiology reports is common for clinicians and radiologists. However, it is laborious and time-consuming when the amount of reports to be read is large. Assisting clinicians to locate and assimilate the key information of reports is of great significance for improving the efficiency of reading reports. There are few studies on information extraction from Chinese medical texts and its application in radiology information systems (RIS) for efficiency improvement. OBJECTIVES: The purpose of this study was to explore methods for extracting, grouping, ranking, delivering, and displaying medical-named entities in radiology reports which can yield efficiency improvement in RISs. METHODS: A total of 5,000 reports were obtained from two medical institutions for this study. We proposed a neural network model called Multi-Embedding-BGRU-CRF (bidirectional gated recurrent unit-conditional random field) for medical-named entity recognition and rule-based methods for entity grouping and ranking. Furthermore, a methodology for delivering and displaying entities in RISs was presented. RESULTS: The proposed neural named entity recognition model has achieved a good F1 score of 95.88%. Entity ranking achieved a very high accuracy of 99.23%. The weakness of the system is the entity grouping approach which yield accuracy of 91.03%. The effectiveness of the overall solution was proved by an evaluation task performed by two clinicians based on the setup of actual clinical practice. CONCLUSIONS: The neural model shows great potential in extracting medical-named entities from radiology reports, especially for languages, that lack lexicons and natural language processing tools. The pipeline of extracting, grouping, ranking, delivering, and displaying medical-named entities could be a feasible solution to enhance RIS functionality by information extraction. The integration of information extraction and RIS has been demonstrated to be effective in improving the efficiency of reading radiology reports.

5.
Front Immunol ; 10: 1647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379845

RESUMO

Background: Antibody-dependent cellular cytotoxicity (ADCC), which mainly mediated by natural killer (NK) cells, may play a critical role in human immunodeficiency virus type-1 (HIV-1) disease progression. However, the potential mechanisms that affecting NK-mediated ADCC response are still not well-elucidated. Methods: Antigen-antibody complex model of Ab-opsonized P815 cells was adopted to induce a typical non-specific ADCC response. The capacities of HIV-1 specific NK-ADCC were measured by using the combination model of gp120 protein and plasma of HIV-1 elite controllers. The levels of plasma cytokine were measured by ELISA. Anti-IL-2 blocking antibody was used to analyze the impact of activated CD56+ T cells on NK-ADCC response. Results: IL-2, IL-15, IFN-α, and IFN-ß could effectively enhance the non-specific and HIV-1-specific NK-ADCC responses. Compared with healthy controls, HIV-1-infected patients showed decreased plasma IL-2 levels, while no differences of plasma IFN-α, IL-15, and IFN-ß were presented. IL-2 production was detected from CD56+ T cells activated through antibody-dependent manner. The capability of NK-ADCC could be weakened by blocking IL-2 secretion from activated CD56+ T cells. Although no difference of frequencies of CD56+ T cells was found between HIV-1-infected patients and healthy controls, deficient IL-2 secretion from activated CD56+ T were found in chronic HIV-1 infection. Conclusions: The impaired ability of activated CD56+ T cells to secreting IL-2 might contribute to the attenuated NK cell-mediated ADCC function in HIV-1 infection.

6.
Sci Rep ; 9(1): 7095, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068640

RESUMO

In present study, transmission electron microscopy and flow cytometry were utilized to investigate the classification, characterization and immune functions of hemocytes from horseshoe crab, Tachypleus tridentatus and Carcinoscorpius rotundicauda. Three types of hemocytes were distinguished respectively: the granular cell, the semi-granular cell and the hyaline cell by transmission electron microscopy, while three hemocyte subpopulations (Gate 1 cell, Gate 2 cell, Gate 3 cell) were classified by flow cytometry. Hyaline cell was the major cell type with the highest nuclear-cytoplasmic ratio and granular cell and semi-granular cell showed lower ratios. Immune parameters of hemocytes in horseshoe crabs were investigated by flow cytometry. Different hemocyte subpopulations respond for diverse functions. Lysosomal contents and hemocyte mortality in Gate 3 cell subpopulation were higher than that in other subpopulations, while reactive oxygen species, phagocytosis and non-specific esterase, in Gate 1 cell subpopulation, were higher than those in other subpopulations. The hemocyte types between the two species had no significant differences in staining or morphology.

7.
Antonie Van Leeuwenhoek ; 112(10): 1545-1552, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31114973

RESUMO

A Gram-stain negative, non-motile and short rod shaped bacterium, designated strain DSL-12T, was isolated from seawater of the East China Sea and characterised phylogenetically and phenotypically. Optimal growth was found to occur at 28 °C (range 4-40 °C), pH 7 (range 6-12) and with 3% (w/v) NaCl (range 0-8%). Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain DSL-12T is related to members of the genus Algoriphagus and shares high sequence similarities with Algoriphagus boritolerans DSM 17298T (97.6%) and Algoriphagus alkaliphilus DSM 22703T (97.6%). The 16S rRNA gene sequence identities between strain DSL-12T and other current members of the genus Algoriphagus were below 96.4%. The digital DNA-DNA hybridization values between strain DSL-12T and the type strains A. boritolerans DSM 17298T and A. alkaliphilus DSM 22703T were found to be 21.2 ± 2.4% and 20.2 ± 2.4%, respectively. The average nucleotide identity (ANI) values between strain DSL-12T and A. boritolerans DSM 17298T and A. alkaliphilus DSM 22703T were found to be 83.2% and 82.8%, respectively. The sole respiratory quinone was identified as MK-7. The major polar lipids were identified as phosphatidylethanolamine, diphosphatidylglycerol, one unidentified phospholipid and two unidentified lipids. The major fatty acids identified as were iso-C15:0, summed feature 8 (C18:1ω7c and/or C18:1ω6c), C16:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C17:0. The G+C content of the genomic DNA was determined to be 43.3 mol%. The combined genotypic and phenotypic data indicate that strain DSL-12T represents a novel species of the genus Algoriphagus, for which the name Algoriphagus litoralis sp. nov. is proposed, with the type strain DSL-12T (= KCTC 62647T = MCCC 1K03536T).


Assuntos
Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação , Água Doce/microbiologia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Bacteroidetes/fisiologia , Composição de Bases , China , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Concentração de Íons de Hidrogênio , Lagos , Locomoção , Hibridização de Ácido Nucleico , Oceanos e Mares , Fosfolipídeos/análise , Filogenia , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Temperatura Ambiente
8.
Sci Rep ; 8(1): 17497, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30504858

RESUMO

Either HIV or HCV monoinfection could result in an abnormal status of platelets. As two key indicators reflecting activation and function of platelets, the changes of platelet counts and mean platelet volume (MPV) in HIV/HCV-coinfected patients have not been clearly identified. In the present study, a total of 318 former plasma donors were investigated in 2006, and 66% (201 individuals) of primary recruiters were followed up in 2014. By horizontal comparison in 2006, the decrease of platelet counts in HIV/HCV coinfection was greater than that in HIV or HCV monoinfection. MPV scores were lower in HIV monoinfection compared with healthy controls, while no difference was found in HIV/HCV coinfection. Platelet counts were shown to be negatively correlated with MPV scores in total recruited population (r = 0.432, P < 0.001). Interestingly, by comparison of data from two time points of 2006 and 2014, significant decrease of platelets (P = 0.004) and increase of MPV (P = 0.004) were found only in HCV monoinfected patients, which may associate with slow progression of hepatic fibrosis induced by chronic HCV infection. Nonetheless, no significant changes of platelet counts and MPV were found from 2006 to 2014 in coinfected patients. In conclusion, HCV coinfection aggravated the decrease of platelet counts, but not MPV score in chronic HIV infection. MPV showed poor applicability in reflecting the status of platelets in HIV/HCV-coinfected patients.


Assuntos
Infecções por HIV/sangue , Hepatite C/complicações , Contagem de Plaquetas , Infecções por HIV/complicações , Humanos , Volume Plaquetário Médio
9.
BMC Infect Dis ; 18(1): 254, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29866105

RESUMO

BACKGROUND: Female gender and favorable IFNL3 genotypes are the primary independent predictors of spontaneous clearance of HCV infection. However, chronic hepatitis C infection occurs in numerous women carrying favorable IFNL3 genotypes, indicating that other host and/or virological factors contribute to the prognosis of infection. METHODS: A cohort of 137 anti-HCV-positive female Han Chinese cases, including 64 chronic HCV carriers and 73 HCV spontaneous resolvers, was recruited in the study. 111 SNPs in 23 genes encoding HCV co-receptors, transcription factors, Toll-like receptors, co-stimulating molecules, and cytokines were selected for SNP analysis. RESULTS: After comparison of genotypes and allelotype frequencies of 111 SNPs in 23 genes in the primary cohort, the SNPs rs9826 (P = 0.024 for CC/TT/CT; P = 0.015 for C allele/T allele) and rs1521177 (P = 0.017 for GG/TT/GT; P = 0.006 for G allele/T allele) in the RORC gene were significantly associated with spontaneous HCV clearance. In the sub-cohort carrying favorable IFNL3 genotypes (rs12979860CC, rs8099917 TT, rs12980275 AA), rs1521177 (genotype: P = 0.040; allelotype: P = 0.021) remained significantly associated with spontaneous HCV clearance. Importantly, the most common RORC haplotype rs9826-T/rs1521177-T was presented at significantly different frequencies in resolvers and carriers in both the primary cohort (P = 0.0027) and the IFNL3 favorable sub-cohort (P = 0.0117). CONCLUSIONS: This study indicates that genetic polymorphisms in human Th17-related RORC gene are associated with different natural prognosis of HCV infection. The RORC haplotype, rs9826-T/rs1521177-T, was favorable for spontaneous clearance of HCV infection.


Assuntos
Hepatite C Crônica/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Polimorfismo de Nucleotídeo Único , Células Th17/fisiologia , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Feminino , Genótipo , Haplótipos , Humanos , Interferons , Interleucinas/genética , Pessoa de Meia-Idade , Remissão Espontânea , Células Th17/virologia
10.
Toxicol Appl Pharmacol ; 352: 107-118, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29660438

RESUMO

Accumulating evidence has shown that the impact of prenatal environmental factors on the organs of the offspring could last until the adulthood. Here, we aimed to investigate these effects and the potential mechanism of prenatal nicotine exposure (PNE) on the female adult cartilage of the first generation (PNE-F1) and the second generation (PNE-F2). Pregnant Wistar rats were injected with 2.0 mg/kg.d nicotine from gestational day (GD) 9 to 20. Then their F1 generation at GD20 and postnatal week (PW) 12, and F2 generation at PW12 were harvested. The expression of extracellular matrix (ECM) and transforming growth factor ß (TGFß) signaling genes were analyzed by real-time quantitative PCR, and the histone acetylation was examined by chromatin immunoprecipitation assay. The results showed that PNE reduced the ECM and TGFß signaling gene expressions in both PNE-F1 and PNE-F2 female adult articular cartilage. In the F1 generation, PNE inhibited the acetylation at H3K9 of TGFß, TGFß receptor 1 (TGFßR1), SRY-type high mobility group box 9 (SOX9), a1 chain of type II collagen (COL2A1) and aggrecan (ACAN) gene promoters at both GD20 and PW12. In PNE-F2 at PW12, the obvious deacetylation at H3K9 of the TGFßR1 and COL2A1 promoters still existed. Moreover, in rat fetal chondrocytes, corticosterone rather than nicotine directly induced the hypoacetylation of H3K9 of TGFßR1 and COL2A1 genes, which might be the main cause of imperfect cartilage for PNE-F2. This study may be helpful to elucidate the developmental variability of articular cartilage quality and useful for the early prevention of articular damage.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Histonas/metabolismo , Nicotina/toxicidade , Agonistas Nicotínicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Acetilação , Fatores Etários , Agrecanas/genética , Agrecanas/metabolismo , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Condrogênese/genética , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Idade Gestacional , Masculino , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Gravidez , Ratos Wistar , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Mar Environ Res ; 137: 49-59, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29503109

RESUMO

Biochemical responses of the mussel Mytilus coruscus exposed to different concentrations of titanium dioxide nanoparticles (nano-TiO2) (0, 2.5, 10 mg L-1) and two pH levels (pH 8.1 and pH 7.3) for 14 days. Mussel responses were also investigated after a 7 days recovery period (pH 8.1 and no nanoparticle). Exposure to nano-TiO2 led changes in antioxidant indexes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH)), biotransformation enzyme activity (GST) and malondialdehyde level (MDA) in gills and digestive glands. An increase in MDA level and a decrease in SOD and GSH activities were observed in gill of mussels exposed to 10 mg L-1 nano-TiO2. This effect was more severe in mussels kept at pH 7.3 as compared to pH 8.1. A different response was observed in the digestive gland as SOD, CAT and GSH levels increased in mussels exposed to nano-TiO2. These contrasting results in digestive glands and gills were only evident at high concentration of nano-TiO2 and low pH. A 7 days recovery period was not sufficient to fully restore SOD, GPx, GST, GSH and MDA levels to levels before exposure to nano-TiO2 and low pH. Overall, our results confirmed that seawater acidification modulates effects of nanoparticles in mussels, and that gills are more sensitive to these stressors as compared with digestive glands.


Assuntos
Mytilus/fisiologia , Nanopartículas/toxicidade , Estresse Oxidativo/fisiologia , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brânquias , Água do Mar/química
12.
Front Physiol ; 9: 166, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29559924

RESUMO

With the release of large amounts of CO2, ocean acidification is intensifying and affecting aquatic organisms. In addition, salinity also plays an important role for marine organisms and fluctuates greatly in estuarine and coastal ecosystem, where ocean acidification frequently occurs. In present study, flow cytometry was used to investigate immune parameters of haemocytes in the thick shell mussel Mytilus coruscus exposed to different salinities (15, 25, and 35‰) and two pH levels (7.3 and 8.1). A 7-day in vivo and a 5-h in vitro experiments were performed. In both experiments, low pH had significant effects on all tested immune parameters. When exposed to decreased pH, total haemocyte count (THC), phagocytosis (Pha), esterase (Est), and lysosomal content (Lyso) were significantly decreased, whereas haemocyte mortality (HM) and reactive oxygen species (ROS) were increased. High salinity had no significant effects on the immune parameters of haemocytes as compared with low salinity. However, an interaction between pH and salinity was observed in both experiments for most tested haemocyte parameters. This study showed that high salinity, low salinity and low pH have negative and interactive effects on haemocytes of mussels. As a consequence, it can be expected that the combined effect of low pH and changed salinity will have more severe effects on mussel health than predicted by single exposure.

13.
Cell Death Differ ; 25(8): 1442-1456, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29352270

RESUMO

Dysregulation of Wnt signaling has been implicated in developmental defects and in the pathogenesis of many diseases such as osteoarthritis; however, the underlying mechanisms are poorly understood. Here, we report that non-canonical Wnt signaling induced loss of chondrocyte phenotype through activation of Fz-6/DVL-2/SYND4/CaMKIIα/B-raf/ERK1/2 cascade. We show that in response to Wnt-3a, Frizzled 6 (Fz-6) triggers the docking of CaMKIIα to syndecan 4 (SYND4) and that of B-raf to DVL-2, leading to the phosphorylation of B-raf by CaMKIIα and activation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling, which leads to chondrocyte de-differentiation. We demonstrate that CaMKIIα associates and phosphorylates B-raf in vitro and in vivo. Our study reveals the mechanism by which non-canonical Wnt activates ERK1/2 signaling that induces loss of chondrocyte phenotype, and demonstrates a direct functional relationship between CaMKIIα and B-raf during chondrocyte de-differentiation. The identification of Fz-6, SYND4, and B-raf as novel physiological regulators of chondrocyte phenotype may provide new potential anti-osteoarthritic targets.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Desdiferenciação Celular , Proteínas Desgrenhadas/metabolismo , Receptores Frizzled/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Sindecana-4/metabolismo , Proteínas Wnt/metabolismo , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Proteínas Desgrenhadas/antagonistas & inibidores , Proteínas Desgrenhadas/genética , Receptores Frizzled/antagonistas & inibidores , Receptores Frizzled/genética , Humanos , Sistema de Sinalização das MAP Quinases , Osteoartrite/metabolismo , Osteoartrite/patologia , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas B-raf/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Sindecana-4/antagonistas & inibidores , Sindecana-4/genética , beta Catenina/antagonistas & inibidores , beta Catenina/genética , beta Catenina/metabolismo
14.
Sci Total Environ ; 624: 820-830, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29274606

RESUMO

Flow cytometry was used to investigate the immune parameters of haemocytes in thick-shell mussel Mytilus coruscus exposed to different concentrations of ZnO nanoparticles (NPs) (0, 2.5, and 10mgl-1) at two pH levels (7.3 and 8.1) for 14days following a recovery period of 7days. ZnO NPs significantly affected all of the immune parameters throughout the experiment. At high ZnO NPs concentrations, total haemocyte counting, phagocytosis, esterase, and lysosomal content were significantly decreased whereas haemocyte mortality and reactive oxygen species (ROS) were increased. Although low pH also significantly influenced all of the immune parameters of the mussels, its effect was not as strong as that of ZnO NPs. Interactive effects were observed between pH and ZnO NPs in most haemocyte parameters during the exposure period. Although a slight recovery from the stress of ZnO NPs and pH was observed for all immune parameters, significant carry-over effects of low pH and ZnO NPs were still detected. This study revealed that high concentration of ZnO NPs and low pH exert negative and synergistic effects on mussels, and these effects remain even after the mussels are no longer exposed to such stressors.


Assuntos
Hemócitos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Mytilus/imunologia , Água do Mar/química , Óxido de Zinco/toxicidade , Animais , Esterases/metabolismo , Concentração de Íons de Hidrogênio , Lisossomos , Mytilus/efeitos dos fármacos , Fagocitose , Espécies Reativas de Oxigênio/metabolismo
15.
Appl Environ Microbiol ; 84(5)2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29269502

RESUMO

Oxidative stresses commonly exist in natural environments, and microbes have developed a variety of defensive systems to counteract such events. Although increasing evidence has shown that high hydrostatic pressure (HHP) and low temperature (LT) induce antioxidant defense responses in cells, there is no direct evidence to prove the connection between antioxidant defense mechanisms and the adaptation of bacteria to HHP and LT. In this study, using the wild-type (WT) strain of a deep-sea bacterium, Shewanella piezotolerans WP3, as an ancestor, we obtained a mutant, OE100, with an enhanced antioxidant defense capacity by experimental evolution under H2O2 stress. Notably, OE100 exhibited better tolerance not only to H2O2 stress but also to HHP and LT (20 MPa and 4°C, respectively). Whole-genome sequencing identified a deletion mutation in the oxyR gene, which encodes the transcription factor that controls the oxidative stress response. Comparative transcriptome analysis showed that the genes associated with oxidative stress defense, anaerobic respiration, DNA repair, and the synthesis of flagella and bacteriophage were differentially expressed in OE100 compared with the WT at 20 MPa and 4°C. Genetic analysis of oxyR and ccpA2 indicated that the OxyR-regulated cytochrome c peroxidase CcpA2 significantly contributed to the adaptation of WP3 to HHP and LT. Taken together, these results confirmed the inherent relationship between antioxidant defense mechanisms and the adaptation of a benthic microorganism to HHP and LT.IMPORTANCE Oxidative stress exists in various niches, including the deep-sea ecosystem, which is an extreme environment with conditions of HHP and predominantly LT. Although previous studies have shown that HHP and LT induce antioxidant defense responses in cells, direct evidence to prove the connection between antioxidant defense mechanisms and the adaptation of bacteria to HHP and LT is lacking. In this work, using the deep-sea bacterium Shewanella piezotolerans WP3 as a model, we proved that enhancement of the adaptability of WP3 to HHP and LT can benefit from its antioxidant defense mechanism, which provided useful insight into the ecological roles of antioxidant genes in a benthic microorganism and contributed to an improved understanding of microbial adaptation strategies in deep-sea environments.


Assuntos
Antioxidantes/metabolismo , Evolução Biológica , Temperatura Baixa , Pressão Hidrostática , Shewanella/fisiologia , Adaptação Fisiológica , Peróxido de Hidrogênio/farmacologia , Shewanella/genética , Estresse Fisiológico , Ativação Transcricional
17.
Mar Pollut Bull ; 120(1-2): 99-108, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28479147

RESUMO

We examined prey selection and foraging behaviors of the crab Charybdis japonica exposed to four combinations of pH (7.3 and 8.1) and temperature (18°C and 25°C). The order of prey selection by C. japonica was Potamocorbula laevis, Ruditapes philippinarum, Tegillarca granosa and Mactra veneriformis. Under high pCO2, times for searching, breaking, eating and handling were all significantly longer than those at the normal pCO2, and the prey profitability and predation rate under high pCO2 were significantly lower than normal pCO2. Moreover, temperature significantly influenced the foraging behaviors, but its effects were not as strong as those of pH; times for searching, eating and handling under high temperature were significantly lower than the low temperature, and the prey predation rates under high temperature was significantly higher than low temperature. In conclusion, high pCO2 negatively affected the foraging behavior, but high temperature actively stimulated the foraging behaviors of crabs.


Assuntos
Braquiúros , Comportamento Predatório , Temperatura Ambiente , Animais , Concentração de Íons de Hidrogênio , Água do Mar
18.
Retrovirology ; 13(1): 76, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27814766

RESUMO

BACKGROUND: Antibody-dependent cellular cytotoxicity (ADCC), which mainly mediated by natural killer (NK) cells, may play a critical role in slowing human immunodeficiency virus type-1 (HIV-1) disease progression and protecting from HIV-1 infection. Besides classic NK cells, CD56+ T cells also have some NK cell-like properties, such as the large granular lymphocyte morphology and the capacity to destroy NK-sensitive target cells. However, little is known about the potentials of antibody-dependent CD56+ T cell responses and the association between antibody-dependent CD56+ T cell responses and HIV-1 disease progression. RESULTS: In the present study, we showed evidences that, in addition to NK cells, CD56+ T cells could generate degranulation upon CD16 cross-linking. Ex vivo study showed that FcγRIII (CD16)-mediated CD56+ T cell responses were distinctly induced by IgG antibody-bound P815 cells. Comparatively, CD56- T cells and invariant NKT (CD3+ 6B11+) failed to induce antibody-dependent activation. Antibody-dependent CD56+ T cell responses were mainly ascribed to CD4/CD8 double negative subset and were functionally impaired in long-term HIV-1-infected former plasma donors, regardless of hepatitis C virus (HCV) coinfection status. Also, CD56+ T cell-mediated HIV-1-specific antibody-dependent responses were declined in men who have sex with men with HIV-1 infection over 3 years. Finally, we showed that matrix metalloprotease (MMP) inhibitor GM6001 could partially restored antibody-dependent CD56+ T cell responses of chronic HIV-1-infected subjects. CONCLUSIONS: Our results suggested that CD56+ T cells could mediate ADCC responses and the responses were impaired in chronic HIV-1 infection.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Antígeno CD56/imunologia , Infecções por HIV/imunologia , Infecções por HIV/fisiopatologia , Subpopulações de Linfócitos T/imunologia , Adulto , Doença Crônica , Coinfecção/virologia , Dipeptídeos/uso terapêutico , Progressão da Doença , Proteínas Ligadas por GPI/metabolismo , Infecções por HIV/sangue , Infecções por HIV/virologia , Sobreviventes de Longo Prazo ao HIV , Hepatite C/virologia , Homossexualidade Masculina , Humanos , Masculino , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Células T Matadoras Naturais/imunologia , Receptores de IgG/metabolismo , Fatores de Tempo
19.
PLoS One ; 11(9): e0163447, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27668427

RESUMO

BACKGROUND: Ovarian cancer is the most lethal type of malignant tumor in gynecological cancers and is associated with a high percentage of late diagnosis and chemotherapy resistance. Thus, it is urgent to identify a tumor marker or a molecular target that allows early detection and effective treatment. RNA-binding proteins (RBPs) are crucial in various cellular processes at the post-transcriptional level. The eukaryotic translation initiation factor 4 gamma, 1(eIF4G1), an RNA-binding protein, facilitates the recruitment of mRNA to the ribosome, which is a rate-limiting step during the initiation phase of protein synthesis. However, little is known regarding the characteristics of eIF4G1 expression and its clinical significance in ovarian cancer. Therefore, we propose to investigate the expression and clinicopathological significance of eIF4G1 in ovarian cancer patients. METHODS: We performed Real-time PCR in 40 fresh serous ovarian cancer tissues and 27 normal ovarian surface epithelial cell specimens to assess eIF4G1mRNA expression. Immunohistochemistry (IHC) was used to examine the expression of eIF4G1 at the protein level in 134 patients with serous ovarian cancer and 18 normal ovarian tissues. Statistical analysis was conducted to determine the correlation of the eIF4G1 protein levels with the clinicopathological characteristics and prognosis in ovarian cancer. RESULTS: The expression of eIF4G1 was upregulated in serous ovarian cancer tissues at both the mRNA (P = 0.0375) and the protein (P = 0.0007) levels. The eIF4G1 expression was significantly correlated with the clinical tumor stage (P = 0.0004) and omentum metastasis (P = 0.024). Moreover, patients with low eIF4G1 protein expression had a longer overall survival time (P = 0.026). CONCLUSIONS: These data revealed that eIF4G1 is markedly expressed in serous ovarian cancer and that upregulation of the eIF4G1 protein expression is significantly associated with an advanced tumor stage. Besides, the patients with lower expression of eIF4G1 tend to have a longer overall survival time. Thus, eIF4G1 may contribute to the occurrence and metastasis of ovarian cancer and can serve as a potential therapeutic target for the treatment of ovarian cancer.

20.
Food Funct ; 6(7): 2266-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26067873

RESUMO

Excessive proliferation of vascular smooth muscle cells is a crucial event in the pathogenesis of several cardiovascular diseases, including atherosclerosis and restenosis. In this study, we reported that stigmasterol was effective in inhibiting vascular cell proliferation exemplified by using A7r5 cells stimulated by Ang II. Mechanism analysis showed that this inhibiting effect mainly occurred by the arrest of the cell-cycle and promotion of apoptosis. In addition, stigmasterol inhibition effects were detected in association with decreased ROS production, enhanced SOD and CAT activity, decreased abundance of cyclin A, CDK2, PCNA, bax and bcl-2, and increased levels of p53 protein. Our study provided implications for the development of therapeutic strategies to protect against certain cardiovascular pathologies, such as atherosclerosis and restenosis.


Assuntos
Angiotensina II/metabolismo , Aorta/citologia , Miócitos de Músculo Liso/citologia , Substâncias Protetoras/farmacologia , Estigmasterol/farmacologia , Animais , Aorta/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina A/genética , Ciclina A/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Transdução de Sinais
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