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1.
Curr Microbiol ; 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33527165

RESUMO

The genus Algibacter belongs to the family Flavobacteriaceae of the Bacteroidetes, and all members of this genus were isolated from marine environments. Among the Algibacter species, two members, Algibacter lectus KMM 3902T and Algibacter wandonensis WS-MY22T, were isolated from green algae and sediment around a brown algae respectively. The 16S rRNA gene sequences of these two type strains possess 99.4% sequence similarity. In this study, further studies were undertaken to clarify the taxonomic assignments of the two species. Whole-genome sequence analysis showed that the similarities for other phylogenetic markers are also very high (i.e. 99.9% for gyrB, 99.6% for recA and 99.9% for rpoD). Average nucleotide identity, average amino acids identity and digital DNA-DNA hybridization value between A. lectus KMM 3902T and A. wandonensis WS-MY22T are 98.3%, 98.6% and 89.4% respectively, all clearly exceed suggested species delineation thresholds. Furthermore, phylogenetic trees based on sequences of 16S rRNA gene and up-to-date bacterial core gene set (UBCG) consisting of 92 genes provided additional evidence that A. lectus KMM 3902T and A. wandonensis WS-MY22T are very closely related. In addition, a review of their profiles indicated that A. lectus KMM 3902T and A. wandonensis WS-MY22T did not present pronounced differences at phenotypic and chemotaxonomic levels. Based on these evidence, we propose that A. wandonensis should be reclassified as later heterotypic synonyms of A. lectus.

2.
Antonie Van Leeuwenhoek ; 114(2): 137-149, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33392935

RESUMO

Two Gram-stain-negative, oxidase- and catalase-positive, aerobic strains (CY05T and H18S-6) were isolated from sediment samples of the Yellow Sea, China. The strains were positive for denitrification. Optimum growth was observed at 20 °C, pH 7.5-8.0 and with 2.0%-3.0% NaCl. The predominant cellular fatty acids (> 10%) were summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), major respiratory quinone was ubiquinone-10 and main polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid and one unidentified aminolipid. The approximate genome size of strains CY05T and H18S-6 were 4.86 and 5.04 Mbp, the genomic G + C content of them were 54.2 and 54.5%, respectively. Both of the phylogenetic analysis based on 16S rRNA gene sequences and the up-to-date bacterial core gene (UBCG) sequences revealed that strains CY05T, H18S-6 and Pelagicola marinus DSW4-44T formed a distinct monophyletic clade within the family Rhodobacteraceae. The ANI and isDDH values between strains CY05T and H18S-6 were 94.0% and 56.5%, between CY05T and Pelagicola marinus DSW4-44T were 94.1% and 59.8%, respectively, all below the accepted threshold value for species delineation. But the ANI and isDDH values between strains H18S-6 and Pelagicola marinus DSW4-44T were 96.8% and 76.7% respectively, indicating that strains H18S-6 and Pelagicola marinus DSW4-44T belong to the same species. Based on the distinctive polyphasic evidence, CY05T represent a novel species of a novel genus of the family Rhodobacteraceae, for which the name Zongyanglinia huanghaiensis gen. nov., sp. nov. is proposed. The type strain is CY05T (= MCCC 1K04409T = KCTC 62200T). Moreover, the reclassification of Pelagicola marinus Choi et al. 2019 as Zongyanglinia marinus comb. nov. (type strain DSW4-44T = KCTC 62762T = KCCM 43261T = JCM 33637T) is proposed based on the polyphasic taxonomic data obtained in this study.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33479873

RESUMO

In this study, the concentrations of 16 kinds of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Daya Bay were determined and analyzed. Results showed that 16 PAHs were detected in all the samples, and the total PAH concentration ranged from 70.18 to 128.04 ng g-1, with an average of 103.17 ng g-1. The cyclic number distribution of PAHs in the sediments was mainly 4 and 5 rings. Six classic PAH ratios named Ant/(Ant + Phe), Fla/(Fla + Pyr), [InP/(InP + BghiP)], [BaA/(BaA + Chr)], BaA/BghiP, and LMW/HMW, and principal component analyses showed that the main source of PAHs in this region was combustion (biomass, coal, and petroleum combustion), and the secondary source was petroleum. The ecological risk analysis of PAHs by using effect range low/median method and mean effects range-median quotient method showed that all of PAHs are lower than the effect range low (ERL) level and the effects range-median quotient (M-ERM-Q) value of all stations is 0.0027-0.0067, with an average value of 0.0046. Thus, it can be seen that PAHs are at a low-risk level in surface sediments of Daya Bay.

4.
Mar Pollut Bull ; : 111800, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33168144

RESUMO

The distribution, source, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in surface sediments were analyzed and discussed at 15 sampling sites in Yazhou Bay, Sanya. Results showed that the total PAH content in the surface sediments of Yazhou Bay ranged from 13.20 ng/g to 40.37 ng/g, and the average content was 31.53 ng/g. Component analysis showed that the distribution of various PAHs in the surface sediments of Yazhou Bay was relatively average, and 3- and 4-ring PAHs were the dominant species. PAHs were traced by characteristic ratio method and principal component analysis. PAHs in the surface sediments mainly came from combustion sources, including incomplete combustion of petroleum, coal, and biomass, which also indicated the existence of petroleum sources. The ecological risk assessment results of surface sediments showed that, compared with effect range low and effect range median (ERM) of the ecological risk of 14 kinds of PAHs detected, no ecological risk existed for PAHs of all sampling sites in Yazhou Bay. The mean ERM quotient analysis also showed that PAHs in the sediments in Yazhou Bay were at a low risk level.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33090733

RESUMO

Sphingosine-1-phosphate (S1P) binding to the S1P-1 receptor (S1P1R) controls the egress of lymphocytes from lymphoid organs and targets modulation of immune responses in autoimmune diseases. Pharmacologic modulation of S1P receptors has been linked to heart rate reduction. BMS-986166, a prodrug of the active phosphorylated metabolite BMS-986166-P, presents an improved cardiac safety profile in preclinical studies compared to other S1P1R modulators. The pharmacokinetics, safety, and pharmacodynamics of BMS-986166 versus placebo after single (0.75-5.0 mg) and repeated (0.25-1.5 mg/day) oral administration were assessed in healthy participants after a 1-day lead-in placebo period. A population model was developed to jointly describe BMS-986166 and BMS-986166-P pharmacokinetics and predict individual exposures. Inhibitory sigmoid models described the relationships between average daily BMS-986166-P concentrations and nadir of time-matched (day -1) placebo-corrected heart rate on day 1 (nDDHR, where DD represents ∆∆) and nadir of absolute lymphocyte count (nALC). Predicted decreases in nDDHR and nALC were 9 bpm and 20% following placebo, with maximum decreases of 10 bpm in nDDHR due to drug effect, and approximately 80% in nALC due to drug and placebo. A 0.5-mg/day dose regimen achieves the target 65% reduction in nALC associated with a 2-bpm decrease in nDDHR over placebo.

6.
Mar Pollut Bull ; 159: 111499, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32745747

RESUMO

Intertidal sediment samples from Shilaoren Bay, Qingdao, China, were collected to determine the concentrations and compositions of 16 polycyclic aromatic hydrocarbons (PAHs). The sources of PAHs were analyzed, and risk assessment was performed. Results show that the pollution level of PAHs in the investigated area was low. The majority of PAHs are four-ring PAHs. The PAHs in this region were mainly derived from combustion sources, including the incomplete combustion of petroleum, coal, and biomass, such as vegetation, which were affected to some extent by petroleum sources. The highest concentration of PAHs in all sampling sites was lower than that of effects range low, and the mean effects range median quotient was low. Therefore, the PAHs in the study area did not have toxic and side effects on the ecological environment, and ecological risk was low.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Baías , China , Monitoramento Ambiental , Sedimentos Geológicos , Medição de Risco
7.
Front Oncol ; 10: 669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528873

RESUMO

Temozolomide (TMZ) is considered a standard chemotherapeutic agent for glioblastoma (GBM). Characterizing the biological molecules and signaling pathways involved in TMZ sensitivity would be helpful for selecting therapeutic schemes and evaluating prognosis for GBM. Thus, in the present study, we selected 34 glioma cell lines paired with specific IC50 values of TMZ obtained from CancerRxGene and RNA-seq data downloaded from the Cancer Cell Line Encyclopedia to identify genes related to TMZ sensitivity. The results showed that 1,373 genes were related to the response of GBM cells to TMZ. Biological function analysis indicated that epithelial-mesenchymal transition, Wnt signaling, and immune response were the most significantly activated functions in TMZ-resistant cell lines. Additionally, negative regulation of telomere maintenance via telomerase was enriched in TMZ-sensitive glioma cell lines. We also preliminarily observed a synergistic effect of combination treatment comprising TMZ and a telomerase inhibitor in vitro. We identified six genes (MROH8, BET1, PTPRN2, STC1, NKX3-1, and ARMC10) using the random survival forests variable hunting algorithm based on the minimum error rate of the gene combination and constructed a gene expression signature. The signature was strongly related to GBM clinical characteristics and exhibited good prognosis accuracy for both The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) datasets. Patients in the high score group had a shorter survival time than those in the low score group (11.2 vs. 22.2 months, hazard ratio = 7.31, p = 4.59e-11) of the TCGA dataset. The CGGA dataset was selected as a validation group with 40 patients in the high score set and 43 patients in the low score set (12.5 vs. 28.8 months, hazard ratio = 3.42, p = 8.61e-5). Moreover, the signature showed a better prognostic value than MGMT promoter methylation in both datasets. We also developed a nomogram for clinical use that integrated the TMZ response signature and four other risk factors to individually predict patient survival after TMZ chemotherapy. Overall, our study provides promising therapeutic targets and potential guidance for adjuvant therapy of GBM.

8.
Exp Gerontol ; 137: 110967, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32387125

RESUMO

As a pacesetter for physiological processes, variation in metabolic rate can determine the shape of energetic trade-offs and thereby drive variation in life-history traits. In turn, such variation in metabolic performance and life-histories can have profound consequences for lifespan and lifetime fitness. Thus, the extent to which metabolic rate variation is due to phenotypic plasticity or fixed genetic differences among individuals or populations is likely to be shaped by natural selection. Here, we first present a generalized framework describing the central role of mitochondria in processes linking environmental, genomic, physiological, and aging variation. We then present a test of these relationships in an exemplary system: populations of garter snakes (Thamnophis elegans) exhibiting contrasting life-history strategies - fast-growing, early-reproducing, and fast-aging (FA) versus slow-growing, late-reproducing, and slow-aging (SA). Previous work has characterized divergences in mitochondrial function, reactive oxygen species processing, and whole-organism metabolic rate between these contrasting life-history ecotypes. Here, we report new data on cellular respiration and mitochondrial genomics and synthesize these results with previous work. We test hypotheses about the causes and implications of mitochondrial genome variation within this generalized framework. First, we demonstrate that snakes of the FA ecotype increase cellular metabolic rate across their lifespan, while the opposite pattern holds for SA snakes, implying that reduced energetic throughput is associated with a longer life. Second, we show that variants in mitochondrial genomes are segregating across the landscape in a manner suggesting selection on the physiological consequences of this variation in habitats varying in temperature, food availability, and rates of predation. Third, we demonstrate functional variation in whole-organism metabolic rate related to these mitochondrial genome sequence variants. With this synthesis of numerous datasets, we are able to further characterize how variation across levels of biological organization interact within this generalized framework and how this has resulted in the emergence of distinct life-history ecotypes that vary in their rates of aging and lifespan.

9.
Int J Syst Evol Microbiol ; 70(5): 3497-3503, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32379018

RESUMO

A novel rod-shaped and Gram-stain-negative bacterium, designated strain RZ05T, was isolated from a sand sample collected from the intertidal zone of the Yellow Sea, PR China. Results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RZ05T clusters within the genus Maribacter, a member of the family Flavobacteriaceae, and has the highest sequence similarity to Maribacter polysiphoniae KCTC 22021T (97.8 %), followed by Maribacter arenosus KCTC 52191T (97.2 %). Cells of this strain were observed to be aerobic, oxidase- and catalase-positive, motile by gliding and formed yellow colonies. Growth occurred at 7-40 °C (optimum, 30 °C), at pH 6.5-9.5 (optimum, pH 7.0) and with 0.5-6 % (optimum, 2 %) NaCl. Its polar lipid profile included phosphatidylethanolamine, two unidentified glycolipids, one unidentified aminolipid and four unidentified lipids. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, iso-C16 : 0 3-OH, iso-C15 : 0 3-OH, summed feature 9 (10-methyl C16 : 0/iso-C17 : 1 ω9c) and summed feature 3 (iso-C15 : 0 2-OH/C16 : 1 ω7c/C16 : 1 ω6c). The only respiratory quinone was menaquinone 6 (MK-6). The genome of strain RZ05T was 4.65 Mbp with a G+C content of 38.9 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain RZ05T and its most closely related type strain M. polysiphoniae KCTC 22021T were 80.3 and 26.3  %, respectively. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that strain RZ05T represents a novel species of the genus Maribacter, for which the name Maribacter luteus sp. nov. is proposed. The type strain is RZ05T (=KCTC 62834T=MCCC 1K03617T).


Assuntos
Filogenia , Areia/microbiologia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/classificação , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Br J Clin Pharmacol ; 86(9): 1849-1859, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32198939

RESUMO

AIMS: Branebrutinib (BMS-986195) is a potent, highly selective, oral, small-molecule, covalent inhibitor of Bruton's tyrosine kinase (BTK). This study evaluated safety, pharmacokinetics and pharmacodynamics of branebrutinib in healthy participants. METHODS: This double-blind, placebo-controlled, single- and multiple-ascending dose (SAD; MAD) Phase I study (NCT02705989) enrolled participants into 3 parts: SAD, MAD and JMAD (MAD in first-generation Japanese participants). In each part, participants were randomised 3:1 to receive branebrutinib (SAD: 0.3-30 mg; [J]MAD: 0.3-10 mg) or placebo. Participants in the MAD parts received branebrutinib daily for 14 days and were followed for 14 days postdosing. Safety was assessed by monitoring, laboratory and physical examinations, vital signs, and recording adverse events (AEs). Pharmacodynamics were assessed with a mass spectrometry assay that measured drug-occupied and free BTK. RESULTS: The SAD, MAD and JMAD parts of the study included 40, 32 and 24 participants. Branebrutinib was well tolerated and AEs were mild/moderate, except for 1 serious AE that led to discontinuation. Branebrutinib was rapidly absorbed, with maximum plasma concentration occurring within 1 hour and a half-life of 1.2-1.7 hours, dropping to undetectable levels within 24 hours. BTK occupancy was rapid, with 100% occupancy reached after a single 10-mg dose. BTK occupancy decayed predictably over time (mean half-life in MAD panels: 115-154 hours), such that pharmacodynamic effects were maintained after branebrutinib plasma levels fell below the lower limit of quantification. CONCLUSION: Rapid and high occupancy of BTK and the lack of notable safety findings support further clinical development of branebrutinib.

11.
Metallomics ; 12(4): 631, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32207509

RESUMO

Correction for 'Bis(ethylmaltolato)oxidovanadium(iv) inhibited the pathogenesis of Alzheimer's disease in triple transgenic model mice' by Zhijun He et al., Metallomics, 2020, DOI: 10.1039/c9mt00271e.

12.
Antonie Van Leeuwenhoek ; 113(7): 919-931, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32219666

RESUMO

Microbial taxonomy is the foundation of microbiology and rapid advancements in DNA sequencing technologies are providing new approaches to address prevailing questions in this field. The family Colwelliaceae, which currently comprises four genera, is a diverse and globally abundant group of Gamaproteobacteria. Based on 14 publically available genomes of bacteria strains labeled as members of the family Colwelliaceae, phylogenomic analyses were conducted to revisiting the taxonomic status of this family both in the genus and species level. Using genome-based phylogeny as a primary guideline and genome-based similarity indexes including average amino acid identity, percentage of conserved proteins, average nucleotide identity, and the digital DNA-DNA hybridization as supplements, the following taxonomic proposals were proposed: Colwellia polaris, Colwellia beringensis, Colwellia sediminilitoris, Colwellia aestuarii, Colwellia chukchiensis and Colwellia mytili should be reclassified into the novel genus Cognaticolwellia; Colwellia agarivorans should be reclassified into the novel genus Pseudocolwellia. Our results constitute a solid framework for current and future taxonomic decisions within this family, which will be helpful for avoiding confusion with ecological and evolutionary interpretations in subsequent studies.

13.
Metallomics ; 12(4): 474-490, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31970356

RESUMO

Vanadium compounds have been reported to mimic the anti-diabetes effects of insulin on rodent models, but their effects on Alzheimer's disease (AD) have rarely been explored. In this paper, 9-month-old triple transgenic AD model mice (3×Tg-AD) received bis(ethylmaltolato)oxidovanadium(iv) (BEOV) at doses of 0.2 mmol L-1 (68.4 µg mL-1) and 1.0 mmol L-1 (342 µg mL-1) for 3 months. BEOV at both doses was found to improve contextual memory and spatial learning in AD mice. It also improved glucose metabolism and protected neuronal synapses in the AD brain, as evidenced respectively by 18F-labeled fluoro-deoxyglucose positron emission tomography (18F-FDG-PET) scanning and by transmission electron microscopy. Inhibitory effects of BEOV on ß-amyloid (Aß) plaques and neuronal impairment in the cortex and hippocampus of fluorescent AD mice were visualized three-dimensionally by applying optical clearing technology to brain slices before confocal laser scanning microscopy. Western blot analysis semi-quantitatively revealed the altered levels of Aß42 in the brains of wildtype, AD, and AD treated with 0.2 and 1.0 mmol L-1 BEOV mice (70.3%, 100%, 83.2% and 56.8% in the hippocampus; 82.4%, 100%, 66.9% and 42% in the cortex, respectively). The mechanism study showed that BEOV increased the expression of peroxisome proliferator-activated receptor γ (PPARγ) (140%, 100%, 142% and 160% in the hippocampus; 167%, 100%, 124% and 133% in the cortex) to inactivate the JAK2/STAT3/SOCS-1 pathway and to block the amyloidogenesis cascade, thus attenuating Aß-induced insulin resistance in AD models. BEOV also reduced protein tyrosine phosphatase 1B (PTP1B) expression (74.8%, 100%, 76.5% and 53.8% in the hippocampus; 71.8%, 100%, 94.2% and 81.8% in cortex) to promote insulin sensitivity and to stimulate the PI3K/Akt/GSK3ß pathway, subsequently reducing tau hyperphosphorylation (phosphorylated tau396 levels were 51.1%, 100%, 56.1% and 50.2% in the hippocampus; 22.2%, 100%, 36.1%, and 24% in the cortex). Our results suggested that BEOV reduced the pathological hallmarks of AD by targeting the pathways of PPARγ and PTP1B in 3×Tg AD mice.

14.
Hum Vaccin Immunother ; 16(3): 654-663, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31567046

RESUMO

For the development of safe and effective EBV (Epstein-Barr virus) vaccines, the Ag85A signal peptide from M. tuberculosis H37Rv was used to construct a recombinant secretory BCG (Bacillus Chalmette-Guérin) plasmid. The Ag85A gene, fused to the EBV LMP2A (latent membrane protein) and hGM-CSF (human granulocyte/macrophage colony-stimulating factor) genes, was inserted into the pMV261 vector (secretory BCG plasmid). The expression levels of the hGM-CSF and LMP2A proteins in rBCG (recombinant BCG) were measured by Western blot analysis. Humoral immunity, cellular immunity, and antitumor effects were determined by a series of experiments. The recombinant pMVGCA plasmid effectively expressed GCA (hGM-CSF and LMP2A fusion protein) in BCG after transformation, and the rBCG proteins were recognized by antibodies against hGM-CSF and LMP2A. Six weeks after immunization, the maximum dose of rBCG resulted in antibody titers of 1:19,800 (hGM-CSF antibody) and 1:21,800 (LMP2A antibody). When the effector:target ratio was 40:1, specific lysis was maximal and approximately two times stronger than that in mice immunized with the control. Tumorigenicity was lower in the rBCG treatment group, with a tumor inhibition rate of 0.81 ± 0.09 compared with the control groups. EB virus-positive tumors are inhibited by rBCG expressing an hGM-CSF and LMP2A fusion protein.

15.
Antonie Van Leeuwenhoek ; 113(4): 449-458, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31701358

RESUMO

A Gram-stain negative, rod-shaped, aerobic, oxidase-positive and catalase-weakly positive bacterial strain with polar or subpolar flagellum, designated RZ04T, was isolated from an intertidal sand sample collected from a coastal area of the Yellow Sea, China. The organism was observed to grow optimally at 25 °C and pH 6.5-7.0 with 2% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RZ04T was closely related to Colwellia asteriadis (similarity 96.9%) and Litorilituus sediminis (similarity 96.8%), and 94.4-96.4% sequence similarities to other type strains of species of the genera belonged to the family Colwelliaceae. The dominant fatty acids of strain RZ04T were determined to be C17:1ω8c, C15:1ω8c, C16:0 and summed feature 3 (C16:1ω6c and/or C16:1ω7c), and the predominant isoprenoid quinone was determined to be quinone 8 (Q-8). Phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminophospholipid and four unidentified lipids were determined to be the major constituents of the polar lipids. The genome of strain RZ04T is 4.14 Mbp with a G + C content of 37.4 mol%. A total of 3631 genes are predicted, with 3531 protein-coding genes, 75 RNA genes and 25 pseudogenes. Based on phenotypic, genotypic and phylogenetic analysis, strain RZ04T is considered to represent a novel species in the genus Litorilituus, for which the name Litorilituus lipolyticus is proposed. The type strain is RZ04T (= MCCC 1K03616T = KCTC 62835T). An emended description of Colwellia asteriadis is also provided.


Assuntos
Alteromonadaceae/classificação , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Alteromonadaceae/genética , China , DNA Bacteriano/genética , Gammaproteobacteria/genética , Genótipo , Humanos , Oceanos e Mares , Filogenia , Areia , Especificidade da Espécie
16.
Mar Pollut Bull ; 150: 110690, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31708108

RESUMO

To master the distribution patterns and environmental risk of 16 USEPA preferential polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Laizhou Bay, 20 samples were collected and investigated in this survey. The average PAH concentration in these sediments ranged from 268.97 ng/g to 895.37 ng/g with an average of 612.52 ng/g, thereby suggesting a relatively low PAH pollution in Laizhou Bay compared with other bays in the world. Tricyclic PAHs account for 79% of the total PAH content and were eventually identified as the most crucial component of these sediments. The PCA-MLR results identify fossil fuel combustion, biomass burning, and coke oven as the main sources of PAHs that account for 26.69%, 67.16%, and 6.15% of the total PAH concentration in the collected sediments, respectively. The effect range low/effect range median (ERL/ERM) reveal the low toxicity of PAHs in these sediments. However, the concentration of Fle at each survey site exceeds the ERL level. Meanwhile, the mean effects range-median quotient (M-ERM-Q) indicates the low level of ecological risk of PAHs in the surface sediments from Laizhou Bay. However, the contingency risk of Fle and Phe cannot be ruled out.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Baías , China , Sedimentos Geológicos/química , Medição de Risco
17.
Cells ; 8(12)2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835634

RESUMO

Ribosomes are essential for protein synthesis in all organisms and their biogenesis and number are tightly controlled to maintain homeostasis in changing environmental conditions. While ribosome assembly and quality control mechanisms have been extensively studied, our understanding of ribosome degradation is limited. In yeast or animal cells, ribosomes are degraded after transfer into the vacuole or lysosome by ribophagy or nonselective autophagy, and ribosomal RNA can also be transferred directly across the lysosomal membrane by RNautophagy. In plants, ribosomal RNA is degraded by the vacuolar T2 ribonuclease RNS2 after transport by autophagy-related mechanisms, although it is unknown if a selective ribophagy pathway exists in plants. In this review, we describe mechanisms of turnover of ribosomal components in animals and yeast, and, then, discuss potential pathways for degradation of ribosomal RNA and protein within the vacuole in plants.


Assuntos
Ribossomos/metabolismo , Animais , Autofagia/fisiologia , Humanos , Lisossomos/metabolismo , RNA/metabolismo , Vacúolos/metabolismo
18.
PeerJ ; 7: e8098, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772843

RESUMO

Delta bovine papillomaviruses (δBPVs) causes fibropapillomas or bladder cancer in cattle. E5 is the major oncogene of δBPVs; however, the influence that E5 oncogene has on host microRNA (miRNA) and mRNA expression profiles remains little elucidated. In the present study, small RNA sequencing and RNA sequencing were used to explore alterations in miRNAs and mRNAs in E5 over-expressing Madin-Darby bovine kidney (MDBK) cells compared with controls. In total, 77 miRNAs (including 30 bovine-derived miRNAs) and 223 genes were differentially expressed (DE) following E5 overexpression. The dysregulated genes were mainly involved in metabolic and biosynthetic processes. We constructed a potential miRNA-gene regulatory network from the differentially expressed genes (DEGs) and DE miRNAs. Finally, 22 DEGs and nine DE miRNAs were selected for RT-qPCR validation. Of these, downregulation of six miRNAs, bta-miR-34c, bta-miR-122, bta-miR-195, bta-miR-449b, bta-miR-2425-5p, and bta-miR-2428-3p were confirmed; In addition, upregulation of 16 genes, ACSS2, DDIT4, INHBE, INSIG1, PNRC1, PSAT1, PSPH, PYCR1, SC4MOL, SLC34A2, SCD, SPARC, IDI1, PCK2, HMGCS1, and SMIM14 and downregulation of two genes, BATF3 and WFDC2 were confirmed. Specially, bta-miR-34c and bta-miR-449b potentially regulated PYCR1 and DDIT4, which were involved in cancer progression and angiogenesis. Our study presented for the first time the comprehensive miRNA and mRNA alterations in MDBK cells expressing the BPV E5 oncogene, providing new insights into the tumorigenesis induced by BPV E5.

19.
Ultrasonics ; 99: 105962, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31336223

RESUMO

Particle breakage has been recognized as a crucial factor affecting the mechanical behavior of stressed granular assemblages. To understand such underlying micro-mechanical behavior, Acoustic Emission (AE) technique that is capable of continuously diagnosing the deterioration and failure process of stressed materials was employed into single particle compression tests on silica sands. Regardless of different particle sizes, the fracturing process could be highly featured by AE characteristics, in which AE hit rate and peak frequency characteristics were analyzed to evaluate the intensity and mode of micro-mechanical behaviors, respectively. "Early warning omens" regarding the impending failure of the stressed particle is revealed in terms of the initiation and rapid increase of high-frequency AE components, as well as the rapid increase of AE hit rate. The effect of "prehistory of failure" on the stressed particle is sensitively featured by the highly emitted AE events after the catastrophic failure. Furthermore, a frequency-based method is suggested to distinguish different modes of micro-mechanical behaviors associated with particle readjustment, asperity abrasion, and microcracking. Further employment of the present result is expected to continuously evaluate the intensity and mode of particle interactions in stressed granular assemblages.

20.
Opt Lett ; 44(13): 3266-3269, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31259937

RESUMO

An ultra-compact half-wavelength pitch silicon waveguide array with very low crosstalk is proposed and analyzed in this work. We first show the design of a pair of low-crosstalk silicon waveguides with only half-wavelength spacing, where the placement of two thin silicon strips asymmetrically in between the waveguides is key to having very low crosstalk. We next extend this nano-structured two-waveguide design to form a low-crosstalk half-wavelength pitch silicon waveguide array. Coupled-mode theory shows that, for an array length of 1 mm, the insertion loss of the input waveguide is as low as -0.13 dB for the TE-like mode at 1550 nm, and the crosstalk in all other waveguides remains below about -18 dB. This half-wavelength pitch waveguide array also exhibits a favorable fabrication error tolerance when taking into account the waveguide width variations in practice. It offers a promising platform for realization of integrated optical phased arrays for solid-state lidars with a large field of view.

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