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1.
Huan Jing Ke Xue ; 42(5): 2550-2557, 2021 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-33884826

RESUMO

The spread of antibiotic resistance has become a serious threat to global public health. Recently, several studies have found that non-antibiotic chemicals can promote the generation and spread of bacterial antibiotic resistance. However, the effects of herbicides on the antibiotic resistance of bacteria remain unclear. In this study, Escherichia coli DH5α was used as the model strain to explore the effects of three commonly used herbicides (glyphosate, glufosinate, and dicamba) on the antibiotic resistance under soil environmental concentrations. The results showed that herbicide exposure affected the sensitivity of E. coli DH5α to antibiotics and significantly improved the resistance of E. coli DH5α to gentamicin (glyphosate > dicamba > glufosinate). After 30 d of herbicide exposure, the E. coli mutant strains enhanced the resistance to tetracycline, chloramphenicol, and aminoglycoside antibiotics, and the minimum inhibitory concentration of streptomycin was increased by 19.8 times. The whole-genome sequencing results illustrated that herbicides induced several previously well-characterized mutations associated with membrane proteins (ompF and papC), fimbriae proteins (yraH), and ribosomes (rpsL) related to antibiotic resistance. Together, the results showed that herbicides can enhance the antibiotic resistance of bacteria via inducing genetic mutations, thereby promoting the potential risk of the spread of antibiotic resistance genes in the environment.


Assuntos
Herbicidas , Antibacterianos/toxicidade , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Herbicidas/toxicidade , Testes de Sensibilidade Microbiana
2.
Front Immunol ; 12: 623764, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868240

RESUMO

Long non-coding RNAs (lncRNAs) play widespread roles in fundamental biological processes, including immune responses. The olive flounder (Paralichthys olivaceus), an important economical flatfish widely cultured in Japan, Korea, and China, is threatened by infectious pathogens, including bacteria, viruses, and parasites. However, the role of lncRNAs in the immune responses of this species against pathogen infections is not well-understood. Therefore, in this study, we aimed to identify lncRNAs in the intestine of olive flounder and evaluate their differential expression profiles during Edwardsiella tarda infection, which is an important zoonotic and intestinal pathogen. A total of 4,445 putative lncRNAs were identified, including 3,975 novel lncRNAs and 470 annotated lncRNAs. These lncRNAs had shorter lengths and fewer exons compared with mRNAs. In total, 115 differentially expressed lncRNAs (DE-lncRNAs) were identified during E. tarda infection. To validate the expression pattern of lncRNAs, six DE-lncRNAs were randomly selected for quantitative real-time PCR. The co-located and co-expressed mRNAs of DE-lncRNAs were predicted, which were used to conduct the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The target genes of DE-lncRNAs enriched numerous immune-related processes and exhibited a strong correlation with immune-related signaling pathways. To better understand the extensive regulatory functions of lncRNAs, the lncRNA-miRNA-mRNA regulatory networks were constructed, and two potential competing endogenous RNA (ceRNA) networks, LNC_001979-novel_171-Potusc2 and LNC_001979-novel_171-Podad1, were preliminarily identified from the intestine of olive flounders for the first time. In conclusion, this study provides an invaluable annotation and expression profile of lncRNAs in the intestine of olive flounder infected with E. tarda; this forms a basis for further studies on the regulatory function of lncRNAs in the intestinal mucosal immune responses of olive flounder.

3.
J Vet Pharmacol Ther ; 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675107

RESUMO

Tiamulin fumarate (TIF) is a pleuromutilin antibiotic and has high activity against animal bacterial pathogens including aquatic bacterial pathogens. However, its pharmacokinetic profiles, tissue distribution characteristics and bioavailability in aquatic animals remain unknown. The objective of this study was to investigate the pharmacokinetics and tissue distribution regularities of TIF in tilapia (Oreochromis niloticus) following a single oral (PO) dose of 20 mg/kg body weight (bw) and a single intravenous (IV) dose of 5 mg/kg bw at 22 ± 1°C, respectively. TIF concentrations in tilapia plasma and tissues were determined using the isotope dilution HPLC-HESI-MS/MS procedure, which was validated according to the guidelines defined by US Food and Drug Administration. TIF was well distributed throughout the body compartments of tilapia judged by the apparent volume of distribution (Vd ) >1 L/kg (6.69 L/kg PO and 1.78 L/kg IV). TIF had a short mean residence time (MRT; 22.82 h PO and 14.61 h IV) and quick total body clearance (CLb ) (0.62 L kg-1  h-1 PO and 0.60 L kg-1  h-1 IV). The total area under the curve (AUCtot ) of plasma were 32.25 µg h-1  ml-1 (PO) and 8.30 µg h-1  ml (IV), respectively, and the oral absolute bioavailability (F%) of TIF was calculated to be approximately 97.1%. For tissue distribution, high concentrations of TIF were found in kidney, and the longest MRT was recorded in bile. The withdrawal time (WT) of TIF in muscle, skin, liver, kidney, gill, and bile was 3.75 (4) and 1.79 (2), 1.77 (2) and 2.06 (3), 6.41 (7) and 1.97 (2), 6.95 (7) and 3.98 (4), 4.92 (5) and 2.36 (3), and 7.06 (8) and 6.16 (7) days after PO and IV administration, respectively. The present investigations indicated that TIF was quickly absorbed, well distributed, rapidly eliminated in tilapia, and it could serve as reference data for establishing use regimen and provide useful information for the further development of TIF in aquaculture.

4.
Fish Shellfish Immunol ; 112: 23-30, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33617959

RESUMO

Galectin-9 is a ß-galactoside-binding lectin which could modulate a variety of biological functions including recognition, aggregation and clearance of pathogen. In this study, one Galectin-9 (named PoGalectin-9) was identified from Japanese flounder Paralichthys olivaceus. PoGalectin-9 belongs to the tandem-repeat type, containing one 127-amino acids CRD domain within N terminal and one 122-amino acids CRD domain within C-terminal. The open reading frame of PoGalectin-9 cDNA was 921 bp encoding 306 amino acids. Sequence similarity comparison confirmed that PoGalectin-9 shared high homology with other Galectin-9. The tissue distribution and expression profiles after bacterial infection were also investigated. PoGalectin-9 was widely distributed in all of the examined tissues of Japanese flounder but was predominantly expressed in the spleen, kidney and intestine. After Edwardsiella tarda challenge, the expression of PoGalectin-9 was up-regulated in spleen and down regulated in kidney. ELISA experiment showed that recombinant PoGalectin-9 (rPoGalectin-9) exhibit binding capacity to lipopolysaccharide (LPS) and peptidoglycan (PGN), which is significantly correlated with the concentration of rPoGalectin-9. Meanwhile, the rPoGalectin-9 protein showed strong agglutinating activities against both Gram-negative bacteria and Gram-positive bacteria. Bacterial binding experiments showed that rPoGalectin-9 could bind all examined bacteria. In conclusion, the present study indicate that PoGalectin-9 might play important roles during the immune responses of Japanese flounder against bacterial pathogens.

5.
Curr Microbiol ; 78(3): 1039-1044, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33543358

RESUMO

Two Gram-stain positive, rod-shaped, endospore-forming, aerobic, thermophilic strains, designated FJAT-2464T and FJAT-52740, were isolated from the sediment collected from Zhangjiang Estuary Mangrove National Nature Reserve in Fujian Province, China. The 16S rRNA gene sequence similarity between strains FJAT-2464T and FJAT-52740 was 100%. The result suggests that strains FJAT-2464T and FJAT-52740 belong to the same genome species, hence only FJAT-2464T was considered for further analysis. Strain FJAT-2464T showed the highest 16S rRNA gene sequence similarities to the type strains of Neobacillus thermocopriae SgZ-7T (99.9%), Neobacillus cucumis AP-6T (97.6%) and Neobacillus drentensis LMG 21831T (97.5%). Growth was observed at 25-65 °C (optimum 60 °C), pH 7.0-8.0 (optimum 8.0) with NaCl tolerance up to 1.0% (w/v) (optimum without NaCl %). The cell-wall peptidoglycan contained meso-diaminopimelic acid and MK-7 was the only respiratory quinone. The major fatty acids were iso-C15:0 and anteiso-C15:0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified aminophospholipid and unidentified lipids. The average nucleotide identity and digital DNA-DNA hybridization values between strain FJAT-2464T and the most closely related strain N. thermocopriae SgZ-7T was below the threshold value for species delineation. Based on the above results, strain FJAT-2464T represents a novel species of the genus Neobacillus, for which the name Neobacillus sedimentimangrovi sp. nov. is proposed. The type strain is FJAT-2464T (= MCCC 1K04406T = KCTC 43264T).

6.
Artigo em Inglês | MEDLINE | ID: mdl-33629479

RESUMO

PURPOSE: To analyze the effect of stereotactic body radiotherapy (SBRT) on colorectal cancer (CRC) patients with lung oligoprogression (OP). METHOD: Patients with lung OP from CRC treated by SBRT at our center were included in this retrospective analysis. The progression-free survival (PFS), change of systemic therapy (CST), local control (LC), and overall survival (OS) were analyzed. Cumulative incidence was used to report CST, and the Kaplan-Meier method was used to evaluate PFS and LC. RESULTS: A total of 17 patients with 38 lung OP lesions treated by SBRT from October 2012 to December 2018 were involved. All patients had undergone radical resection for primary CRC and administered with standard systemic therapy regimens (seven for the first line and 10 for the second line). Among them, nine (52.9%) had received targeted therapy before SBRT, 14 (82.4%) patients underwent chemotherapy, and 12 received targeted therapy after SBRT. Six patients (35.3%) underwent CST after a median time of 5.2 months (range: 1.7-27.5 months). The median follow-up was 9.9 months, and the 1-year OS rate for all patients was 73.5%. Progression was observed in of 14 of 17 patients (82.4%), and the 6-month PFS for all patients was 25.9%. Univariate analysis indicated that only targeted therapy before SBRT was a beneficial prognostic indicator for 6-month PFS (P = .026) and N-PFS (P = .013). The 1-year LC for all 38 lesions was 77.8%, and during and after SBRT, no grade 3 or higher toxicities were observed. CONCLUSION: SBRT combined with systemic therapy made partial CRC patients with lung OP avoid the progress within 6 months and delayed the need for CST to 5.2 months, and targeted therapy before SBRT was a positive indicator of PFS.

7.
Molecules ; 26(2)2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430495

RESUMO

We developed a method for determination of imidacloprid and its metabolites 5-hydroxy imidacloprid, olefin imidacloprid, imidacloprid urea and 6-chloronicotinic acid in Procambarus clarkii (crayfish) tissues using quick, easy, cheap, effective, rugged, and safe (QuEChERS) and high-performance liquid chromatography-triple quadrupole mass spectrometry. Samples (plasma, cephalothorax, hepatopancrea, gill, intestine, and muscle) were extracted with acetonitrile containing 0.1% acetic acid and cleaned up using a neutral alumina column containing a primary secondary amine. The prepared samples were separated using reverse phase chromatography and scanned in the positive and negative ion multiple reaction-monitoring modes. Under the optimum experimental conditions, spiked recoveries for these compounds in P. clarkii samples ranged from 80.6 to 112.7% with relative standard deviations of 4.2 to 12.6%. The limits of detection were 0.02-0.5 µg·L-1, the limits of quantification were 0.05-2.0 µg·L-1 and the method of quantification was 0.05-2.0 µg·kg-1. The method is rapid, simple, sensitive and suitable for rapid determination and analysis of imidacloprid and its metabolites in P. clarkii tissues.

8.
Cell Biol Int ; 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33470475

RESUMO

MiR-370-3p has been demonstrated to be downregulated in patients with endometriosis (EM). However, its role and molecular mechanisms in the progression of EM remain unclear. Real-time polymerase chain reaction was used to measure the expression of miR-370-3p and endothelin-1 (EDN1) in patients with or without EM. After miR-370-3p overexpression or knockdown in ectopic endometrial hEM15A cells, the changes in the proliferation, apoptosis, and migration and invasion capacities were detected by using cell counting kit-8, flow cytometry, and transwell methods. The interplay between miR-370-3p and EDN1 was confirmed by a luciferase reporter assay. Patients with EM showed adverse expression of EDN1 and miR-370-3p, especially in eutopic endometrium and ectopic endometrium. MiR-370-3p inhibited the proliferation, metastasis, and invasion capacities of hEM15A cells and promoted apoptosis. Investigation of its molecular mechanism revealed that miR-370-3p targeted EDN1 to influence the biological functions of hEM15A cells. MiR-370-3p represented as a therapeutic target for EM treatment.

9.
Fish Shellfish Immunol ; 111: 59-68, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33503473

RESUMO

Galectin-8 gene belongs to the agglutinin family, which can specifically recognize ß-galactoside bonds and play essential roles in many biological processes. In this study, we researched the sequence characteristics and immune-related function of Galectin-8 gene in Japanese flounder Paralichthys olivaceus, named PoGalectin-8. The results showed that the open reading frame of PoGalectin-8 was 891 bp, which encoding a protein with 296 amino acid residues and containing typical HXNPR and WGXEE motifs in the N-terminal and C-terminal CRD domains. Sequence alignment showed that PoGalectin-8 was conserved in different aquatic animals and exhibited the highest similarity (95.27%) with Seriola dumerili. PoGalectin-8 expressed in all detected tissues and exhibited the highest expression level in spleen, followed by skin and kidney. After infected by Edwardsiella tarda, the expression of PoGalectin-8 was down-regulated in the spleen and skin tissues of P. olivaceus. Further to study its immune-related functions, the recombinant PoGalectin-8 (rPoGalectin-8) was expressed and purified. The rPoGalectin-8 can specifically bind to lipopolysaccharide and peptidoglycan, the main components of cell walls from Gram-negative and Gram-positive bacteria. Bacteria binding and the microbial agglutinating experiments showed that the rPoGalectin-8 could bind and agglutinate all examined Gram-positive and Gram-negative bacteria. This study implied that PoGalectin-8, as a pattern recognition receptor, may play important roles during immune responses against bacterial infection, which laid a foundation for further functional identification of Galectin-8 in aquatic animal immunity.

10.
Parasitol Res ; 120(3): 1143-1150, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33420623

RESUMO

Gyrodactylus spp. are common monogenean ectoparasites that may lead to significant fish mortality. To find effective anthelmintic agents with lower toxicity, a series of natural saponins were obtained and evaluated for their anthelmintic activity against Gyrodactylus kobayashii and acute toxicity to goldfish (Carassius auratus). Among all tested compounds, six compounds (1, 2, 3, 8, 10, and 13) shown higher anthelmintic activity and safety than widely used formaldehyde-based parasiticides, especially compound 1 having 100% anthelmintic efficacy against G. kobayashii at 0.3 mg/L and a therapeutic index of 16.6. Also, the three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of these saponins have been performed to explore the structural features reasonable for the anthelmintic activity against G. kobayashii. These models demonstrated that the hydroxyl group at C-17 position and the sugar moieties at C-3 position, especially the hydroxyl groups of the sugar moieties, were critical to the anthelmintic activity. The QSAR studies could provide useful information for further rational design and optimization of novel saponins for the control of gyrodactylosis.

11.
Bioresour Technol ; 321: 124493, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33310385

RESUMO

The effects of undulating seasonal temperature change (USTC) (10.1 °C-31.8 °C) on the N and carbon removal efficiency of simultaneous anammox and denitrification (SAD) were investigated, and the recovery performance of SAD was simulated. Results showed that 15 °C was the critical temperature of SAD for N and carbon removal under USTC from summer to winter. The removal efficiency of NH4+-N was improved in the final stage after temperature rise, but still lower than that in summer after long-term low temperature inhibition. The contribution of anammox to N removal was more than denitrification. The abundance of anammox bacteria (AnAOB) in SAD reactor was 8.8%-11.7% from summer to autumn. Candidatus Kuenenia replaced Candidatus Brocadia as the main AnAOB gradually. Finally, AnAOB abundance increased from 4.2% to 6.6% after recovery, and the abundance of denitrifying bacteria (DB) became the highest, which mainly includes Thauera and Hydrogenophaga.


Assuntos
Desnitrificação , Microbiota , Reatores Biológicos , Nitrogênio , Oxirredução , Estações do Ano , Esgotos , Temperatura
12.
Virulence ; 12(1): 165-176, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33372840

RESUMO

Aeromonas hydrophila (A. hydrophila) can cause a number of diseases in both human and animals. A. hydrophila-related infections in aquaculture cause severe economic losses every year throughout the world. The emergence of antibiotic resistance that is due to the abuse of antibiotics has limited the application of antibiotics. Thus, novel approaches are needed to combat with treatment failure of antibiotics caused by resistant bacterial strains. Aerolysin plays a critical role in the pathogenesis of A. hydrophila and has been considered as a novel target for developing drugs based on anti-virulence strategies. Here, we reported that luteolin, a natural product with no anti-A. hydrophila activity, could reduce aerolysin-induced hemolysis by inhibiting aerolysin activity. The binding mode was simulated by molecular docking and dynamics simulation. Then the main binding sites were confirmed by fluorescence quenching assays. We found that luteolin could hindered the formation of functional heptamer of aerolysin according to the results of the oligomerization assay. Moreover, luteolin could protect A549 cells from aerolysin mediated cell death and increase the survival rate of A. hydrophila-infected channel catfish. These findings suggest a novel approach to developing drugs fighting against A. hydrophila, and luteolin can be a promising drug candidate for treatment of A. hydrophila-associated infections.

13.
J Ethnopharmacol ; 265: 113302, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32860893

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Laminaria japonica, a brown seaweed, has been used in Traditional Chinese Medicine (TCM) to treat a variety of diseases including lung cancer. AIM OF THE STUDY: To demonstrate the effects of Fucoxanthin (FX), a major active component extracted from Laminaria japonica on metastasis and Gefitinib (Gef) sensitivity in human lung cancer cells both in vitro and in vivo. MATERIALS AND METHODS: Invasion and migration of lung cancer cells were detected using the wound healing assay and transwell assay. Epithelial-to-mesenchymal transition (EMT) factors and PI3K/AKT/NF-κB pathways were analyzed by western blotting. RNA interference (RNAi) technology was used to silence TIMP-2 gene expression in A549 cells. The anti-metastatic effect of FX was evaluated in vivo in an experimental lung metastatic tumor model. On the other hand, cell counting kit-8 assay was used to study the cell viability of human lung cancer PC9 cells and Gef resistant PC9 cells (PC9/G) after Gef, FX or FX combined with Gef treatment. PC9 xenograft model was established to explore the anti-tumor effect of FX or combined with Gef. Immunohistochemistry staining assay and immunofluorescence staining assay were used to reveal the effects of FX on lung cancer cell proliferation and apoptosis. RESULTS: FX was able to significantly inhibit lung cancer cells migration and invasion in vitro. FX suppressed the expressions of Snail, Twist, Fibronectin, N-cadherin, MMP-2, PI3K, p-AKT and NF-κB, and increased the expression of TIMP-2. Furthermore, knockdown of TIMP-2 attenuated FX-mediated invasion inhibition. Additionally, we demonstrated that FX inhibited lung cancer cells metastasis in vivo. The anti-metastatic effects of FX on lung cancer cells might be attributed to inhibition of EMT and PI3K/AKT/NF-κB pathway. We further demonstrated that the anti-tumor activity of FX was not only limited to the drug sensitive cell lines, but also prominent on lung cancer cells with Gef resistant phenotype. Furthermore, in vivo xenograft assay confirmed that FX inhibited tumor growth and enhanced the sensitivity of lung cancer cells to Gef and this effect may be due to inhibition of tumor cell proliferation and activation of apoptosis. CONCLUSION: Collectively, our findings suggested that FX suppresses metastasis of lung cancer cells and overcomes EGFR TKIs resistance. Thus, FX is worthy of further investigation as a drug candidate for the treatment of lung cancer.


Assuntos
Gefitinibe/farmacologia , Laminaria/química , Neoplasias Pulmonares/tratamento farmacológico , Xantofilas/farmacologia , Células A549 , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Gefitinibe/administração & dosagem , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/prevenção & controle , Inibidor Tecidual de Metaloproteinase-2/genética , Xantofilas/administração & dosagem , Xantofilas/isolamento & purificação , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Cell Death Discov ; 6(1): 116, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33298860

RESUMO

Ischemia/reperfusion (I/R) injury is responsible for liver injury during hepatic resection and liver transplantation. The plasma membrane-bound G protein-coupled bile acid receptor (TGR5) could regulate immune response in multiple liver diseases. Nevertheless, the underlying role of TGR5 in hepatic I/R injury remains largely unknown. This study aimed to investigate the potential mechanism of TGR5 in hepatic I/R injury. Wild-type (WT) and TGR5 knockout (TGR5KO) mice were used to perform hepatic I/R, and macrophages were isolated from mice for in vitro experiments. The results demonstrated that knockout of TGR5 in mice significantly exacerbated liver injury and inflammatory response. TGR5KO mice infused with WT macrophages showed relieved liver injury. Further study revealed that TGR5 knockout inhibited sirtuin 3 (SIRT3) and forkhead box O3 (FOXO3) expression. In vitro experiments indicated that SIRT3 inhibited acetylation, ubiquitination and degradation of FOXO3. FOXO3 inhibited HIF-1α transcription by binding to its promoter. TGR5 knockout inhibited SIRT3 expression, thus promoted the acetylation, ubiquitination, and degradation of FOXO3, which resulted in increased HIF-1α transcription and macrophages proinflammatory response. Collectively, TGR5 plays a critical protective role in hepatic I/R injury. FOXO3 deacetylation mediated by SIRT3 can attenuate hepatic I/R injury. TGR5 deficiency aggravates hepatic I/R injury via inhibiting SIRT3/FOXO3/HIF-1α pathway.

15.
Front Vet Sci ; 7: 577234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33251263

RESUMO

The objective of this study was to investigate the bioavailability (BA) and pharmacokinetics (PK) of doxycycline (DC) in channel catfish (Ictalurus punctatus) following a single intravenous injection at 5 mg/kg and a single oral administration at 50 mg/kg at 24°C. The calculation of PK parameters was based on the software 3P97. The plasma samples were determined using ultra-performance liquid chromatography. Following oral administration, the multiple-peak phenomenon presented in concentration vs. time curve of DC at 2 h (107.01 mg/L), 8 h (55.07 mg/L), and 72 h (15.10 mg/L), respectively. The compartmental model cannot simulate the oral concentration vs. time profile beside a non-compartmental model. The calculated parameters of the elimination rate constant (λz), the elimination half-life (t1/2λz ), and the area under the concentration vs. time curve (AUC0-144) were 0.037 1/h, 18.91 h, and 2255.45 µg.h/mL, respectively. After intravenous administration, the concentration vs. time profile of DC was best described by a two-compartmental open model without absorption. The parameters of the distribution rate constant (α), the distribution half-life (t1/2α), the elimination rate constant (ß), the elimination half-life (t1/2ß), the apparent distribution volume at steady state (Vss), the total clearance (Cl) and the area under the concentration vs. time curve (AUC0-∞) were 2.79 1/h, 0.25 h, 0.042 1/h, 16.51 h, 300.00 mL/kg, 14.00 mL/h/kg, and 364.99 µg.h/mL, respectively. For the calculation of BA values at the same condition, the data obtained from intravenous injection were also iterated based on a non-compartmental model, and the corresponding parameters of λz, t1/2λz , Vz, Cl, and AUC0-144 were 0.019 1/h, 36.26 h, 480.00 mL/kg, 9.10 mL/h/kg, and 514.45 µg.h/mL, respectively. However, there was a considerable difference in the same parameter when calculated by compartmental and non-compartmental approaches. Finally, the medium BA value of DC was evaluated to be 43.84%. This study provides future studies with a framework for determining the BA of DC in the development of a new formulation and provides information on the appropriate use of DC in aquaculture.

16.
Sci Total Environ ; 755(Pt 2): 142702, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33049532

RESUMO

Environmental selection of antibiotic resistance genes (ARGs) is considered to be caused by antibiotic or metal residues, frequently used in livestock. In this study we examined three commercial poultry farms to correlate the co-occurrence patterns of antibiotic and metal residues to the presence of ARGs. We quantified 283 ARGs, 12 mobile genetic elements (MGEs), 49 targeted antibiotics, 7 heavy metals and sequenced 16S rRNA genes. The abundance and type of ARG were significantly enriched in manure while soil harbored the most diverse bacterial community. Procrustes analysis displayed significant correlations between ARGs/MGEs and the microbiome. Cadmium (Cd), arsenic (As), zinc (Zn), copper (Cu) and lead (Pb) were responsible for a majority of positive correlations to ARGs when compared to antibiotics. Integrons and transposons co-occurred with ARGs corresponding to 9 classes of antibiotics, especially Class1 integrase intI-1LC. Redundancy analysis (RDA) and Variance partitioning analysis (VPA) showed that antibiotics, metals, MGEs and bacteria explain solely 0.7%, 5.7%, 12.4%, and 21.9% of variances of ARGs in the microbial community, respectively. These results suggested that bacterial composition and horizontal gene transfer were the major factors shaping the composition of ARGs; Metals had a bigger effect on ARG profile than detected antibiotics in this study.

17.
J Vet Pharmacol Ther ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051869

RESUMO

This study aimed to examine the bioavailability (BA) and pharmacokinetic (PK) characteristics of sulfadiazine (SDZ) in grass carp (Ctenopharyngodon idellus) after oral and intravenous administrations. Blood samples were collected at predetermined time points of 0.083, 0.17, 0.5, 1, 2, 4, 8, 16, 24, 48, 72, and 96 hr (n = 6). The samples were extracted and purified by organic reagents and determined by the ultra-performance liquid chromatography. The software named 3P97 was used to calculate relevant PK parameters. The results demonstrated that the concentration-time profile of SDZ was best described by a one-compartmental open model with first-order absorption after a single oral dose. The main PK parameters of the absorption rate constant (Kα ), the absorption half-life (t1/2 Kα ), the elimination rate constant (Ke ), the elimination half-life (t1/2Ke ), and the area under concentration-time profile (AUC0-∞ ) were 0.3 1/h, 2.29 hr, 0.039 1/h, 17.64 hr, and 855.78 mg.h/L, respectively. Following intravenous administration, the concentration-time curve fitted to a two-compartmental open model without absorption. The primary PK parameters of the distribution rate constant (α), the elimination rate constant (ß), the distribution half-life (t1/2α ), the elimination half-life (t1/2ß ), the apparent distribution volume (VSS ), the total clearance (CL), and AUC0-∞ were 9.62 1/hr, 0.039 1/hr, 0.072 hr, 17.71 hr, 0.33 L/kg, 0.013 L h-1  kg-1 , and 386.23 mg.h/L, respectively. Finally, the BA was calculated to be 22.16%. Overall, this study will provide some fundamental information on PK properties in the development of a new formulation SDZ in the future and is partially beneficial for the appropriate usage of SDZ in aquaculture.

18.
Parasitol Res ; 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33094386

RESUMO

Gyrodactylid monogeneans are widespread parasites of teleost fishes, and infection with these parasites results in high host morbidity and mortality in aquaculture. To comprehensively elucidate the immune mechanisms against Gyrodactylus kobayashii, the transcriptome profiles of goldfish (Carassius auratus) skin after challenge with G. kobayashii were first investigated using next-generation sequencing. Approximately 21 million clean reads per library were obtained, and the average percentage of these clean reads mapped to the reference genome was 82.25%. A total of 556 differentially expressed genes (DEGs), including 344 upregulated and 212 downregulated genes, were identified, and 380 DEGs were successfully annotated and assigned to 95 signaling pathways in Kyoto Encyclopedia of Genes and Genomes (KEGG). In addition, 14 pathways associated with immune response were identified mainly including mTOR signaling pathway, cytokine-cytokine receptor interaction, intestinal immune network for IgA production, toll-like receptor signaling pathway, and phagosome. Twelve genes were selected and validated using qRT-PCR. A similar trend of these genes between RNA-Seq and qRT-PCR was observed, indicating that RNA-Seq data was reliable. Besides, the ALP activity and NO content in serum were significantly higher in the infected goldfish compared with the non-infected goldfish. In summary, this study provides better understandings of immune defense mechanisms of goldfish against G. kobayashii, which will support future molecular research on gyrodactylids and facilitate the prevention and treatment of gyrodactylosis in aquaculture.

19.
Med Phys ; 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33128263

RESUMO

PURPOSE: The implementation of radiomics and machine learning (ML) techniques on analyzing two-dimensional gamma maps has been demonstrated superior to the conventional gamma analysis for error identification in intensity modulated radiotherapy (IMRT) quality assurance (QA). Recently, the Structural SIMilarity (SSIM) sub-index maps were shown to be able to reveal the error types of the dose distributions. In this study, we aimed to apply radiomics analysis on SSIM sub-index maps and develop ML models to classify delivery errors in patient-specific dynamic IMRT QA. METHODS: Twenty-one sliding-window IMRT plans of 180 beams for three treatment sites were involved in this study. Four types of machine-related errors of various magnitudes were simulated for each beam at each control point, including the monitor unit (MU) variations, same-directional and opposite-directional shifts of the multileaf collimators (MLCs) and random mispositioning of the MLCs. In the QA process, a total of 1620 portal dose (PD) images were acquired for the beams with and without errors. The predicted PD images of the original beams were set as references. To quantify the agreement between a measured PD image and the corresponding predicted PD image, four difference maps including three SSIM sub-index maps, and one dose difference-derived map were calculated. Then, radiomic features were extracted from the four difference maps of each measured PD image. We tested four typical classifiers including linear discriminant classifier (LDC), two supporting vector machine (SVM) classifiers, and random forest (RF) for this multiclass classification task. A nested cross-validation scheme was used for model evaluations, where the SVM recursive feature elimination method was applied for feature selection. Finally, the performance of the ML model on identifying the error-free and the erroneous cases was compared to that of the conventional gamma analysis. RESULTS: The statistics of the selected features showed that all of the difference maps and the feature categories made balanced contributions to solve this classification task. Best performance was achieved by the Linear-SVM model with average overall classification accuracy of 0.86. Specifically, the average classification accuracies of the shift, opening, and the random errors were around 0.9. Moreover, ~80% of error-free and MU errors were correctly classified. Using gamma analysis, the 3 mm/3% criterion was found insensitive to errors (sensitivity was only 0.33). Although the sensitivity to errors with the 2 mm/2% criterion increased to 0.79, still 8% worse than that of the ML model. CONCLUSIONS: We proposed an ML-based method for machine-related error identification in patient-specific dynamic IMRT QA, where radiomic analysis on SSIM sub-index maps were used for feature extraction. With extensive validation to select the best features and classifiers, high accuracies in error classification were achieved. Compared with the conventional gamma threshold method, this approach has great potential in error identification for the patient-specific IMRT QA process.

20.
Nat Commun ; 11(1): 4658, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938931

RESUMO

Dimethylsulfoniopropionate (DMSP) is an important marine osmolyte. Aphotic environments are only recently being considered as potential contributors to global DMSP production. Here, our Mariana Trench study reveals a typical seawater DMSP/dimethylsulfide (DMS) profile, with highest concentrations in the euphotic zone and decreased but consistent levels below. The genetic potential for bacterial DMSP synthesis via the dsyB gene and its transcription is greater in the deep ocean, and is highest in the sediment.s DMSP catabolic potential is present throughout the trench waters, but is less prominent below 8000 m, perhaps indicating a preference to store DMSP in the deep for stress protection. Deep ocean bacterial isolates show enhanced DMSP production under increased hydrostatic pressure. Furthermore, bacterial dsyB mutants are less tolerant of deep ocean pressures than wild-type strains. Thus, we propose a physiological function for DMSP in hydrostatic pressure protection, and that bacteria are key DMSP producers in deep seawater and sediment.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Água do Mar/química , Água do Mar/microbiologia , Compostos de Sulfônio/metabolismo , Bactérias/isolamento & purificação , Clorofila A/análise , Clorofila A/metabolismo , Genes Bacterianos , Sedimentos Geológicos/química , Pressão Hidrostática , Marinobacter/genética , Marinobacter/isolamento & purificação , Marinobacter/metabolismo , Metagenoma , Mutação , Oceanos e Mares , Prochlorococcus/genética , Prochlorococcus/isolamento & purificação , Prochlorococcus/metabolismo , RNA Ribossômico 16S , Sulfetos/análise , Sulfetos/metabolismo , Compostos de Sulfônio/análise , Synechococcus/genética , Synechococcus/isolamento & purificação , Synechococcus/metabolismo
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