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1.
Int J Syst Evol Microbiol ; 70(3): 1777-1784, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32234113

RESUMO

A Gram-stain-negative, strictly aerobic, oval-shaped, non-motile bacterium with no flagella, designated strain SCR17T, was isolated from a shrimp gill habitat in Tangyin hydrothermal field of Okinawa Trough. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SCR17T formed a lineage within the family 'Rhodobacteraceae', and shared 16S rRNA gene sequence similarity of 93.2-96.2 % to the related genera Aquicoccus and Roseivivax. Strain SCR17T was able to grow with 0-14 % (w/v) NaCl (optimum, 9-10 %). The sole respiratory quinone was ubiquinone-10. The major polar lipids of strain SCR17T comprised phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), an unidentified aminolipid (AL), an unidentified phospholipid (PL) and an unidentified lipid (L). The predominant fatty acids (more than 10 % of the total fatty acids) were C18 : 1ω7c or/and C18 : 1ω6c, anteiso-C15 : 0, C16 : 0 and C19 : 0 cyclo ω8c . The genomic DNA G+C content of strain SCR17T was 67.7 mol%. Based on polyphasic taxonomic analyses, strain SCR17T is considered to represent a novel species in a new genus of the family 'Rhodobacteraceae', for which the name Carideicomes alvinocaridis gen. nov., sp. nov. is proposed. The type strain of Carideicomes alvinocaridis is SCR17T (=JCM 33426T=MCCC 1K03732T). The discovery of a novel host-associated bacterium in hydrothermal fields provides an opportunity for the study of host-bacterial symbiosis in extreme environments.

2.
Fish Shellfish Immunol ; 100: 90-97, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32145449

RESUMO

To understand the efficacy of lactic acid bacteria (LAB) as probiotics on the growth, immune response and intestinal microbiota of turbot Scophthalmus maximus, in this study, the Leuconostoc mesenteroides HY2 strain screened from wide caught fish was bath administrated for juvenile turbot with no bacteria administrated as control. The mRNA levels of toll-like receptors 3 (TLR3), interleukin 8 (IL-8) and interferon induced with helicase C domain 1 (IFIH1) in different organs (i.e. intestine, liver, spleen, kidney, brain and skin) were analyzed using RT-PCR technology. The intestinal microbiota was analyzed by 16S rRNA sequencing, in which principal co-ordinates analysis (PCoA) as well as cluster analysis was performed. The results showed that the specific growth rate of turbot in the LAB treatment was significantly higher than those of the control group (P < 0.05). The expression levels of TLR3, IL-8 and IFIH1 were significantly up-regulated in the organs of LAB treatment, except that IL-8 was slightly down-regulated in kidney. A total of 42 phyla in intestinal microbiota were identified. The composition of intestinal microbiota showed significant differences between LAB treatment and the control group. Shannon index in the LAB treatment was significantly increased while Simpson index significantly declined. The PCoA and cluster analysis exhibited significant differences in the composition and abundance between the two groups. Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria acted as biomarkers which may have effects to promote absorption and/or trigger the immune function. In conclusion, the administration of HY2 strain was capable of improving growth performance of turbot by enhancing immune response and optimizing structure and diversity of intestinal microbiota.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32100699

RESUMO

A Gram-stain-negative, obligately anaerobic, non-motile, non-spore-forming, long-rod-shaped and non-flagellated bacterial strain, designated T3-2 S1-CT, was isolated from a sediment sample collected at the Okinawa Trough. Phylogenetic analyses of 16S rRNA gene sequences and the whole genome revealed that strain T3-2 S1-CT was a member of the family Marinifilaceae and exhibited less than 95.1 % sequence similarities to the closely related type strains of the family Marinifilaceae. Optimal growth occurred at pH 7.0, 28 °C and in the presence of 3 % (w/v) NaCl. The isoprenoid quinone of strain T3-2 S1-CT was identified as menaquinone-7 (MK-7) and the predominant fatty acids (>10 %) were iso-C15 : 0 (38.9 %) and anteiso-C15 : 0 (11.6 %). The major polar lipids were one phosphatidylethanolamine, one phosphatidylmonomethylethanolamine, one aminolipids, two unidentified lipids and two unidentified phospholipids. The DNA G+C content of strain T3-2 S1-CT was 35.7 mol%. On the basis of the results of polyphasic analyses, strain T3-2 S1-CT is considered to represent a novel species of the genus Ancylomarina, for which the name Ancylomarina longa sp. nov. is proposed. The type strain is T3-2 S1-CT (=KCTC 15505T=MCCC 1K01617T).

4.
Int J Syst Evol Microbiol ; 70(3): 1666-1671, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31909707

RESUMO

A Gram-stain-negative, strictly aerobic, non-motile, long, straight-rod and non-flagellated marine bacterium strain, designated SCR12T, was isolated from the gill of a shrimp collected in the Tangyin hydrothermal field of the Okinawa Trough. The growth temperature was in the range of 16-40 °C and the optimum temperature was 37 °C. Optimal growth occurred at pH 6.5 and in the presence of 3 % (w/v) NaCl. The predominant isoprenoid quinone of strain SCR12T was menaquinone-6 (MK-6). The predominant fatty acids (>10 %) were iso-C15 : 0 (44.2 %), iso-C15 : 1 G (19.0 %) and iso-C17 : 0 3-OH (12.1 %). The major polar lipids comprised one phosphatidylethanolamine, three unidentified phospholipids, two unidentified aminolipids and three unidentified lipids. Based on the results of 16S rRNA gene sequence analysis, strain SCR12T was found to be most closely related to Muricauda olearia CL-SS4T (98.09 %), followed by Muricauda beolgyonensis BB-My12T (97.65 %), Muricauda aquimarina SW-63T (97.58 %) and Muricauda ruestringensis DSM 13258T (97.31 %) and with lower sequence similarities (95.74-97.10 %) to other species of the genus Muricauda. Genome relatedness between strain SCR12T and M. olearia CL-SS4T was computed using both average nucleotide identity (ANI) and DNA-DNA hybridization (DDH) and resulted in values of 85.6 % and 29.3±2.3 %, respectively. The genomic DNA G+C content of strain SCR12T was 42.3 mol%. On the basis of polyphasic analysis, the strain SCR12T was considered to represent a novel species of the genus Muricauda, for which the name Muricauda alvinocaridis sp. nov. is proposed. The type strain is SCR12T (=MCCC 1K03731T=JCM 33425T).

5.
Int J Syst Evol Microbiol ; 70(3): 1623-1629, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31961286

RESUMO

Blue holes are unique geomorphological units characterized by steep redox and biogeochemical gradients. Yongle Blue Hole is located on the largest atoll (Yongle Atoll) of the western Xisha Islands in the South China Sea. A Gram-stain-negative, facultatively anaerobic, non-motile, non-flagellated marine bacterium with creamy white colonies, designated JC036T, was isolated from Yongle Blue Hole. Cells were short-rod-shaped and catalase-negative. 16S rRNA gene sequence analysis showed that sequence similarities were lower than 91.6 % against all validly named species in the family Prolixibacteraceae; a reconstructed phylogenetic tree indicated that strain JC036T formed a lineage with strains in the family Prolixibacteraceae. Growth occurred at 4-37 °C (optimum, 28 °C), at pH 5.0-9.0 (optimum, 7.0) and in the presence of 2-6 % (w/v) NaCl (optimum, 3 %). The prevalent isoprenoid quinone of strain JC036T was menaquinone-7 (MK-7). Iso-C15 : 0 and iso-C17 : 0 3-OH were the predominant fatty acids. The major polar lipids included a phospholipid, phosphatidylethanolamine, an aminophospholipid and four unidentified lipids. The genomic DNA G+C content of strain JC036T was 37.8 mol%. Based on physiological and biochemical characteristics and whole genome comparisons, we propose a new genus and species, Puteibacter caeruleilacunae gen. nov., sp. nov., within the family Prolixibacteraceae. The type strain of Puteibacter caeruleilacunae is JC036T (=JCM 33128T=MCCC 1K03579T). From this study, a deeper understanding of the community of the microorganism and their roles in biogeochemical cycles, especially anaerobic bacteria, is provided.

6.
Immunol Cell Biol ; 98(1): 54-66, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625631

RESUMO

Although the detrimental effects of diabetes mellitus/hyperglycemia have been observed in many liver disease models, the function and mechanism of hyperglycemia regulating liver-resident macrophages, Kupffer cells (KCs), in thioacetamide (TAA)-induced liver injury remain largely unknown. In this study, we evaluated the role of hyperglycemia in regulating NOD-like receptor family pyrin domain-containing 3 protein (NLRP3) inflammasome activation by inhibiting autophagy induction in KCs in the TAA-induced liver injury model. Type I diabetes/hyperglycemia was induced by streptozotocin treatment. Compared with the control group, hyperglycemic mice exhibited a significant increase in intrahepatic inflammation and liver injury. Enhanced NLRP3 inflammasome activation was detected in KCs from hyperglycemic mice, as shown by increased gene induction and protein levels of NLRP3, cleaved caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain and interleukin-1ß, compared with control mice. NLRP3 inhibition by its antagonist CY-09 effectively suppressed inflammasome activation in KCs and attenuated liver injury in hyperglycemic mice. Furthermore, inhibited autophagy activation was revealed by transmission electron microscope detection, decreased LC3B protein expression and p-62 protein degradation in KCs isolated from TAA-stressed hyperglycemic mice. Interestingly, inhibited 5' AMP-activated protein kinase (AMPK) but enhanced mammalian target of rapamycin (mTOR) activation was found in KCs from TAA-stressed hyperglycemic mice. AMPK activation by its agonist 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) or mTOR signaling knockdown by small interfering RNA restored autophagy activation, and subsequently, inhibited NLRP3 inflammasome activation in KCs, leading to ultimately reduced TAA-induced liver injury in the hyperglycemic mice. Our findings demonstrated that hyperglycemia aggravated TAA-induced acute liver injury by promoting liver-resident macrophage NLRP3 inflammasome activation via inhibiting AMPK/mTOR-mediated autophagy. This study provided a novel target for prevention of toxin-induced acute liver injury under hyperglycemia.

7.
Plant Cell Environ ; 43(4): 903-919, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31851373

RESUMO

During maize production, drought throughout the flowering stage usually induces seed abortion and yield losses. The influence of postpollination drought stress on seed abortion and its underlying mechanisms are not well characterized. By intervening in the competition for assimilates between kernel siblings under different degrees of postpollination drought stresses accompanied by synchronous pollination (SP) and incomplete pollination (ICP) approaches, the mechanisms of postpollination abortion were investigated at physiological and molecular levels. Upon SP treatment, up to 15% of the fertilized apical kernels were aborted in the drought-exacerbated competition for assimilates. The aborted kernels exhibited weak sucrose hydrolysis and starch synthesis but promoted the synthesis of trehalose-6-phosphate and ethylene. In ICP where basal pollination was prevented, apical kernel growth was restored with reinstated sucrose metabolism and starch synthesis and promoted sucrose and hexose levels under drought stress. In addition, the equilibrium between ethylene and polyamine in response to the drought and pollination treatments was associated with the abortion process. We conclude that competition for assimilates drives postpollination kernel abortion, whereas differences in sugar metabolism and the equilibrium between ethylene and polyamines may be relevant to the "live or die" choice of kernel siblings during this competition.

8.
Front Oncol ; 9: 1080, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681609

RESUMO

Purpose: To analyze the prognostic factors and optimal response interval for stereotactic body radiotherapy (SBRT) in patients with lung oligometastases (OM) or oligoprogression (OP) from colorectal cancer (CRC). Method: Patients with lung OM or OP from CRC treated by SBRT at our hospital were included in this retrospective review. The local control (LC), response to SBRT in different evaluation interval and regional metastases (RM) was analyzed. The risk factor for LC and RM was calculated using the Kaplan-Meier method and compared using the Log-rank test. Multivariate analysis with a Cox proportional hazards model was used to test independent significance. Results: A total of 53 patients with 105 lung metastases lesions treated from 2012 to 2018 were involved in this retrospective study. The median biologically effective dose (BED) for these patients was 100 Gy (range: 75-131.2 Gy). Complete response (CR) increased from 27 (25.7%) to 46 (43.8%) lesions at 1.8 and 5.3 months following SBRT, and at the last follow-up, 52 (49.5%) lesions achieved CR. The median follow-up duration for all patients was 14 months (range: 5-63 months), and 1-year LC was 90.4%. During the follow-up, 10 lesions suffered local relapse after SBRT (9 of them occurred within 8 months after SBRT). The univariate analysis shows BED ≥ 100 Gy (P = 0.003) and gross tumor volume (GTV) < 1.6 cm3 (P = 0.011) were better predictors for 1-year LC. The patients with lung oligoprogression had higher 1-year RM when compared with patients with lung oligometastases (hazard ratio 2.78; 95% confidence interval [CI] 1.04-7.48, P = 0.042). Until the last follow up, 4 (7.5%) patients suffered grade 2 radiation pneumonitis, and no grade 3-4 toxicity was observed. Conclusions: SBRT provides favorable LC in CRC patients with lung OM or OP, and the GTV and BED can affect the LC. Radiology examinations nearly 5-6 months following SBRT appear to represent the final local effect of SBRT, and the patients with oligoprogression has higher RM.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31702534

RESUMO

Two Gram-staining-negative, facultatively anaerobic, motile, short clavate and flagellated marine bacteria, designated strains BEI233T and LJC006T, were isolated from the East China Sea. On the basis of the results of 16S rRNA gene sequencing and multilocus sequence analysis, BEI233T and LJC006T should be assigned to the genus Vibrio. The closest phylogenetic relatives of BEI233T are Vibrio scophthalmi LMG 19158T (98.7 % 16S rRNA gene sequence pairwise similarity), Vibrio ichthyoenteri DSM 14397T (98.5 %), Vibrio renipiscarius KCTC 42287T (97.7 %), Vibrio aestuarianus ATCC 35048T (97.3 %) and Vibrio thalassae MD16T (96.5 %), whereas for LJC006T they were Vibrio furnissii CAIM 518T (97.1 %), Vibrio fluvialis LMG 7894T (97.0%), Vibrio tritonius JCM 16456T (96.9 %) and Vibrio xuii LMG 21346T (96.1 %). The growth of BEI233T occurred at 10-37 °C, pH 5.0-8.0 and with 1-7 % (w/v) NaCl, while the growth of LJC006T occurred at 10-37 °C, pH 6.0-9.0, and 0-8 % (w/v) NaCl. The predominant fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c or/and C16 : 1ω6c), C16 : 0 and summed feature 8 (C18 : 1ω7c or/and C18 : 1ω6c), with different proportions. The DNA G+C contents of BEI233T and LJC006T are 42.41 mol% and 41.88 mol%, respectively. On the basis of the results of polyphasic analysis, BEI233T and LJC006T are considered to represent novel species of the genus Vibrio, for which the names Vibrio sinensis sp. nov. and Vibrio viridaestus sp. nov. are proposed. The type strains are BEI233T (=JCM 32692T=KCTC 62618T) and LJC006T (=JCM 32693T=KCTC 62620T), respectively.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31675288

RESUMO

A Gram-stain-negative, strictly aerobic, rod-shaped bacterium, without flagellum and designated ZYF765T, was isolated from seawater sampled at a depth of 4000 m in the Mariana Trench. Strain ZYF765T grew with 1-15 % (w/v) NaCl (optimum, 4 %), at 16-37 °C (28 °C) and at pH 6.0-10.0 (pH 7.0-8.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZYF765T formed a lineage within the family Hyphomonadaceae, and was distinct from the most closely related species Glycocaulis abyssi, Glycocaulis albus and Glycocaulis alkaliphilus with 16S rRNA gene sequences similarities ranging from 98.42 to 98.63 %. The major respiratory quinone was ubiquinone-10 (Q-10). The polar lipids comprised three unidentified glycolipids, one unidentified aminophospholipid, one unidentified phospholipid and one unidentified aminolipid. The predominant fatty acids (more than 10 % of total fatty acids) were C18  :  1ω7c (46.2 %) and C18  :  0 (14.1 %). The DNA G+C content was 67.7 mol%. On the basis of the results of polyphasic taxonomic analysis, strain ZYF765T is considered to represent a novel species within the genus Glycocaulis, for which the name Glycocaulis profundi sp. nov. is proposed. The type strain is ZYF765T (=JCM 33028T=MCCC 1K03554T).

11.
BMC Plant Biol ; 19(1): 508, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752685

RESUMO

BACKGROUND: Carbohydrate partitioning and utilization is a key determinant of growth rate and of yield in plants and crops. There are few studies on crops in field conditions. In Arabidopsis, starch accumulation in leaves is a negative indicator of growth rate. RESULTS: Here, we wished to establish if starch accumulation in leaves could potentially be a marker for growth rate and yield in crops such as maize. We characterized daily patterns of non-structural carbohydrate (NSC) at different growth stages over two seasons for maize hybrids in the field. In 27 commercial hybrids, we found a significant negative relationship between residual starch in leaves and plant growth, but not with final yield and biomass. We then focused on three typical hybrids and established a method for calculation of C turnover in photosynthetic leaves that took into account photosynthesis, leaf area and NSC accumulation. The ratios of stored NSC decreased from approximately 15% to less than 4% with ongoing ontogeny changes from V7 to 28 days after pollination. CONCLUSION: The proportion rather than absolute amount of carbon partitioned to starch in leaves at all stages of development related well with yield and biomass accumulation. It is proposed that screening plants at an early vegetative growth stage such as V7 for partitioning into storage may provide a prospective method for maize hybrid selection. Our study provides the basis for further validation as a screening tool for yield.


Assuntos
Carbono/metabolismo , Amido/metabolismo , Zea mays/fisiologia , Ontologias Biológicas , Biomassa , Metabolismo dos Carboidratos , Produtos Agrícolas , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Estações do Ano , Zea mays/crescimento & desenvolvimento
12.
Front Genet ; 10: 731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31475036

RESUMO

Olive flounder (Paralichthys olivaceus) is an important economical flatfish in Japan, Korea, and China, but its production has been greatly threatened by disease outbreaks. In this research, we aimed to explore the immune responsive mechanism of P. olivaceus against Edwardsiella tarda infection by profiling the expression of circRNA, miRNA, and mRNA by RNA-seq and constructing a regulatory circular circRNA-miRNA-mRNA network. Illumina sequencing of samples from normal control (H0), 2 h (H2), 8 h (H8), and 12 h (H12) post-challenge was conducted. Differentially expressed (DE) circRNA (DE-circRNAs), miRNAs (DE-miRNAs), and mRNAs [differential expression genes (DEGs)] between challenge and control groups were identified, resulting in a total of 62 DE-circRNAs, 39 DE-miRNAs, and 3,011 DEGs. Based on the differentially expressed gene results, miRNA target interactions (circRNA-miRNA pairs and miRNA-mRNA pairs) were predicted by MiRanda software. Once these paired were combined, a preliminary circRNA-miRNA-mRNA network was generated with 198 circRNA-miRNA edges and 3,873 miRNA-mRNA edges, including 44 DE-circRNAs, 32 DE-miRNAs, and 1,774 DEGs. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed to evaluate the function of the DEGs in this network, and we focused and identified two important intestinal immune pathways (herpes simplex infection and intestinal immune network for IgA production) that showed statistical significance between the challenge and control groups. Furthermore, three critical DEGs (nectin2, MHC II α-chain, and MHC II ß-chain) were identified, mapped into the preliminary circRNA-miRNA-mRNA network, and new circRNA-miRNA-mRNA regulatory networks were constructed. In conclusion, we, for the first time, identified circRNA-miRNA-mRNA network from P. olivaceus in the pathogenesis of E. tarda and provided valuable resources for further analyses of the molecular mechanisms and signaling networks.

13.
FASEB J ; 33(10): 11180-11193, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295018

RESUMO

Liver fibrosis is an important pathologic process in injured liver tissues. A protein kinase, receptor-interacting protein (RIP)3, plays a crucial role in mediating different diseases. However, the role of RIP3 in macrophages in liver fibrosis has not yet been studied. In our study, we found that RIP3 expression was up-regulated in liver tissues and macrophages of humans and mice with liver fibrosis. Absence of RIP3 in macrophages could alleviate inflammation and macrophage or neutrophil accumulation in mice after carbon tetrachloride (CCl4) or bile duct ligation (BDL) treatment. Importantly, RIP3 deficiency in macrophages could decrease CCl4-induced and BDL-induced liver fibrosis in mice. Moreover, RIP3 deficiency could inhibit the TLR4-NF-κB pathway through suppressing Rho-associated coiled-coil containing protein kinase (ROCK)1 in macrophages. To explore the connection of ROCK1 and RIP3 in macrophages of mice with liver fibrosis in vivo, ROCK1-overexpressed macrophages were infused to RIP3-deficient mice, which resulted in increased inflammation and liver fibrosis. In conclusion, our findings suggest that RIP3 plays a crucial proinflammatory role in liver fibrosis by regulating the ROCK1-TLR4-NF-κB signaling pathway in macrophages and therefore may be a potential therapeutic target for immune-mediated liver fibrosis.-Wei, S., Zhou, H., Wang, Q., Zhou, S., Li, C., Liu, R., Qiu, J., Shi, C., Lu, L. RIP3 deficiency alleviates liver fibrosis by inhibiting ROCK1-TLR4-NF-κB pathway in macrophages.

14.
Cell Death Discov ; 5: 119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341645

RESUMO

Although diabetes mellitus/hyperglycemia is a risk factor for acute liver injury, the underlying mechanism remains largely unknown. Liver-resident macrophages (Kupffer cells, KCs) and oxidative stress play critical roles in the pathogenesis of toxin-induced liver injury. Here, we evaluated the role of oxidative stress in regulating KC polarization against acetaminophen (APAP)-mediated acute liver injury in a streptozotocin-induced hyperglycemic murine model. Compared to the controls, hyperglycemic mice exhibited a significant increase in liver injury and intrahepatic inflammation. KCs obtained from hyperglycemic mice secreted higher levels of the proinflammatory factors, such as TNF-α and IL-6, lower levels of the anti-inflammatory factor IL-10. Furthermore, enhanced oxidative stress was revealed by increased levels of reactive oxygen species (ROS) in KCs from hyperglycemic mice post APAP treatment. In addition, ROS inhibitor NAC resulted in a significant decrease of ROS production in hyperglycemic KCs from mice posttreated with APAP. We also analyzed the role of hyperglycemia in macrophage M1/M2 polarization. Interestingly, we found that hyperglycemia promoted M1 polarization, but inhibited M2 polarization of KCs obtained from APAP-exposed livers, as evidenced by increased MCP-1 and inducible NO synthase (iNOS) gene induction but decreased Arg-1 and CD206 gene induction accompanied by increased STAT1 activation and decreased STAT6 activation. NAC restored Arg-1, CD206 gene induction, and STAT6 activation. To explore the mechanism how hyperglycemia regulates KCs polarization against APAP-induced acute liver injury, we examined the AMPK/PI3K/AKT signaling pathway and found decreased AMPK activation and increased AKT activation in liver and KCs from hyperglycemic mice post APAP treatment. AMPK activation by its agonist AICAR or PI3K inhibition by its antagonist LY294002 inhibited ROS production in KCs from hyperglycemic mice post APAP treatment and significantly attenuated APAP-induced liver injury in the hyperglycemic mice, compared to the control mice. Our results demonstrated that hyperglycemia exacerbated APAP-induced acute liver injury by promoting liver-resident macrophage proinflammatory response via AMPK/PI3K/AKT-mediated oxidative stress.

15.
Mol Ther Nucleic Acids ; 16: 758-769, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31150929

RESUMO

Liver fibrosis is a common pathological process of end-stage liver diseases. However, the role of microRNA (miRNA) in liver fibrosis is poorly understood. The activated hepatic stellate cells (HSCs) are the major source of fibrogenic cells and play a central role in liver fibrosis. In this study, we investigated the differential expression of miRNAs in resting and transforming growth factor ß1 (TGF-ß1) activated HSCs by microarray analysis and found that miR-455-3p was significantly downregulated during HSCs activation. In addition, the reduction of miR-455-3p was correlated with liver fibrosis in mice with carbon tetrachloride (CCl4), bile duct ligation (BDL), and high-fat diet (HFD)-induced liver fibrosis. Our functional analyses demonstrated that miR-455-3p inhibited expression of profibrotic markers and cell proliferation in HSCs in vitro. Moreover, miR-455-3p regulated heat shock factor 1 (HSF1) expression by binding to the 3' UTR of its mRNA directly. Overexpression of HSF1 facilitated HSCs activation and proliferation by promoting heat shock protein 47 (Hsp47) expression, leading to activation of the TGF-ß/Smad4 signaling pathway. To explore the clinical potential of miR-455-3p, we injected ago-miR-455-3p into mice with CCl4-, BDL-, and HFD-induced hepatic fibrosis in vivo. The overexpression of miR-455-3p suppressed HSF1 expression and reduced fibrosis marker expression, which resulted in alleviated liver fibrosis in mice. In conclusion, our present study suggests that miR-455-3p inhibits the activation of HSCs through targeting HSF1 involved in the Hsp47/TGF-ß/Smad4 signaling pathway. Therefore, miR-455-3p might be a promising therapeutic target for liver fibrosis.

16.
Int Immunopharmacol ; 73: 261-269, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31121416

RESUMO

Acute liver injury caused by toxins or drugs is a common condition that threatens patients' lives. Inositol-requiring enzyme 1 alpha (IRE1α), the most conserved endoplasmic reticulum (ER) stress sensor, has been implicated in the pathophysiology of liver injury. Activated IRE1α endoribonuclease (RNase) can splice X-box binding protein 1 (XBP1) mRNA to produce the sXBP1 transcription factor. STF-083010, a specific inhibitor of IRE1α RNase, has recently been suggested to exhibit anti-oxidant and anti-inflammatory properties in multiple injury models. However, it remains unknown whether STF-083010 has a protective effect against thioacetamide (TAA)-induced acute liver injury. Here, we demonstrated that IRE1α-sXBP1 signaling is involved in the development of TAA-induced acute liver injury and correlates with the severity of liver damage. STF-083010 protected against TAA-induced liver injury, as evidenced by higher survival rates in response to a lethal dose of TAA and less severe liver injury in response to a toxic dose of TAA. Mechanistic exploration showed that STF-083010 triggered hepatocyte autophagy in response to TAA stimulation both in vivo and in vitro, leading to reduced reactive oxygen species (ROS) production and attenuated hepatic inflammation. We also found that Beclin-1 played a critical role in STF-083010-mediated autophagy in response to TAA stimulation. Autophagy inhibition by chloroquine (CQ) in vivo and Beclin-1 knockdown in vitro markedly abrogated the protective role of STF-083010 against TAA-induced oxidative stress, inflammation and hepatotoxicity. Our results suggested STF-083010 as a potential therapeutic application to prevent TAA-induced acute liver injury.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Endorribonucleases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sulfonamidas/uso terapêutico , Tiofenos/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocinas/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sulfonamidas/farmacologia , Tioacetamida , Tiofenos/farmacologia
17.
Biosens Bioelectron ; 137: 222-228, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121459

RESUMO

Electrochemically active bacteria (EAB) use extracellular electron transfer (EET) to exchange electron with extracellular acceptors. Previous studies regarding the measurement of EAB were based on either extracellular reduction or oxidation. In this work, we developed a simple electrochemiluminescence (ECL) assay for the identification and detection of EAB. The results of this proposed method revealed that EET of EAB influenced the content of dissolved oxygen and the formation of Ru(bpy)32+• thus leading to qualitative changes of the ECL signal. EAB with the ability of extracellular reduction (such as Shewanella oneidensis MR-1) gave enhanced signal on ECL emission while those displaying the ability of extracellular oxidation (i.e., Sulfobacillus acidophilus) showed the opposite effect on ECL emission, but non-EAB (i.e., Escherichia coli) did not. These changes in ECL intensity were also proportional to the cell density that could be quantitatively detected in the concentration range of (1.1 ±â€¯1) × 105-212 ±â€¯2 CFU/mL (i.e. Shewanella oneidensis MR-1). Moreover, the measurement of the ability of EAB using this approach was in agreement with measurements using the dissimilatory Fe(III) reduction method. Compared to previous reports, this method displayed a continual and steady ECL signal that allowed accurate measurements of EAB. Most important, only a low cell density was needed in this Ru(bpy)32+ - based ECL method, which is beneficial for cell detection.


Assuntos
Técnicas Biossensoriais , Contagem de Células/métodos , Compostos Férricos/química , Shewanella/isolamento & purificação , Técnicas Eletroquímicas , Transporte de Elétrons , Medições Luminescentes , Fotometria , Shewanella/química
18.
J Radiol Prot ; 39(3): 739-748, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31042686

RESUMO

Medical exposure to ionizing irradiation has become a recognised carcinogenic risk. Balancing the concomitant imaging dose and positioning accuracy is critical in image-guided-radiotherapy (IGRT) especially for children, whose higher biological susceptibility and longer expected life make them more vulnerable to develop secondary cancer. This work aims to evaluate and benchmark the imaging dose and positioning accuracy of a new MV cone-beam-CT (CBCT)-guided IGRT system, Varian Halcyon, against conventional kV CBCT. Weighted-CT-dose-index (CTDIw) were measured for Varian TrueBeam kV CBCT, and computed for Halcyon MV CBCT using Eclipse system as validated before. Simulating the IGRT workflow, the positioning accuracy of correcting a known shift was tested on various regions of 1-year, 5-year and adult anthropomorphic phantoms, respectively. Inter-scanner and inter-protocol comparisons of dose and accuracy were performed. kV CTDIw for 'Head', 'Thorax', 'Pelvis' and 'Image Gently' (in CTDIΦ16cm/CTDIΦ32cm phantoms, respectively) protocols were measured as 4.5 mGy, 5.4 mGy, 19.3 mGy, and 1.1 mGy/0.5 mGy, respectively. Using 'High Quality' mode, MV CTDIw in the CTDIΦ16cm and CTDI Φ32cm phantoms were computed as 84.5 mGy and 63.8 mGy (imaging length = 28 cm), 68.8 mGy and 55.5 mGy (imaging length = 16 cm), respectively, which were about twice of 'Low Dose' mode. The maximum positioning deviation observed on Halcyon was 0.51 mm ('Low Dose' adult thorax), which was lower than that of standard (0.58 mm, 'Pelvis' adult pelvis) and 'Image Gently' kV CBCT (1.57 mm, adult pelvis). Accuracy of 'Image Gently' kV CBCT head & neck and thoracic imaging were clinically acceptable for adults (maximum deviation = 0.54 mm, adult thorax). Complying with Image Gently campaign, dose-efficient protocols should be used for pediatric IGRT, achieving comparable positioning accuracy on the new Halcyon MV CBCT system relative to the conventional kV CBCT.

19.
Nanomaterials (Basel) ; 9(6)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31142057

RESUMO

l-tryptophan is one of the eight kinds of essential amino acids for sustainable human life activity. It is common to detect the concentration of tryptophan in human serum for diagnosing and preventing brain related diseases. Herein, in this study, GCE (glassy carbon electrode) modified by Ta2O5-reduced graphene oxide (-rGO) composite (Ta2O5-rGO-GCE) is synthesized by the hydrothermal synthesis-calcination methods, which is used for detecting the concentration of tryptophan in human serum under the as-obtained optimal detection conditions. As a result, the obtained Ta2O5-rGO-GCE shows larger electrochemical activity area than other bare GCE and rGO-GCE due to the synergistic effect of Ta2O5 NPs and rGO. Meanwhile, Ta2O5-rGO-GCE shows an excellent response to tryptophan during the oxidation process in 0.1 M phosphate buffer solution (pH = 6). Moreover, three wide linear detection range (1.0-8.0 µM, 8.0-80 µM and 80-800 µM) and a low limit of detection (LOD) of 0.84 µM (S/N = 3) in the detection of tryptophan are also presented, showing the larger linear ranges and lower detection limit by employing Ta2O5-rGO-GCE. Finally, the as-proposed Ta2O5-rGO-GCE with satisfactory recoveries (101~106%) is successfully realized for the detection of tryptophan in human serum. The synthesis of Ta2O5-rGO-GCE in this article could provide a slight view for the synthesis of other electrochemical catalytic systems in detection of trace substance in human serum.

20.
Huan Jing Ke Xue ; 40(4): 1857-1864, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087929

RESUMO

In order to achieve the high value production of methane, this paper investigated the effect and mechanism of hematite on the inhibitation of the formation of hydrogen sulfide during the anaerobic digestion of high-concentration sulfate wastewater. Different dosages of hematite were added to artificially prepared sulfate wastewater to analyze the migration and transformation pathways of sulfur in the reaction system. The results showed that the delay time of the anaerobic digestion process and the hydrogen sulfide concentration in the control reactor were 1.64 times and 180 times those in the reactor with the optimal hematite dosage of 0.5 g·(30 mL)-1, respectively. Thus, the addition of hematite effectively shortened the delay time and reduced the concentration of hydrogen sulfide. Dynamic equilibrium analysis of sulfur in different anaerobic digestion reactors showed that the solid sulfur content in the reactor accounted for 96.9% of the total sulfur. XPS results further demonstrated that hematite mainly enhanced the fixation of S2- in the form of FeS2. Therefore, the addition of hematite can effectively accelerate the anaerobic digestion of sulfate wastewater while reducing the concentration of hydrogen sulfide in the reactor.


Assuntos
Reatores Biológicos , Compostos Férricos/química , Sulfeto de Hidrogênio/química , Sulfatos/química , Águas Residuárias , Anaerobiose
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