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1.
Analyst ; 145(2): 440-444, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31793929

RESUMO

Polymerase chain reaction (PCR) and isothermal amplification methods such as LAMP and RPA are widely used for genetic detection. However, there are some shortcomings of these methods such as dependence on thermocycler instruments for PCR, complexity of primer design, the possibility for nonspecific amplification in LAMP and complexity of components in RPA. We develop a novel isothermal DNA detection system named Recombinase Assisted Loop-mediated Amplification (RALA). Recombinase from Thermus thermophilus (TthRecA) was used to open target double-stranded DNA to initiate loop-mediated amplification under isothermal conditions, which simplified the primer design and circumvented pre-denaturation. A FRET sensor named ProofMan and a proofreading enzyme Pfu were introduced to produce fluorescence signals by cleaving the sensor from the 3' end. Consequently, sequence-specific detection based on the RALA system was achieved, and even a single nucleotide polymorphism (SNP) could be identified. By introducing additional loop primers, the fast RALA version can amplify 102 DNA targets in 30 minutes. In addition to high sensitivity and specificity, the flexibility of choosing different reporting sensors makes this method versatile in either quantitative or qualitative DNA detection.

2.
J Agric Food Chem ; 67(51): 14102-14109, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31790231

RESUMO

Herbicidal activity-guided isolation from the fermentation extract of Penicillium viridicatum had obtained two herbicidal series of polyketides (1-7) and diketopiperazine derivatives (8-11), especially including three novel polyketides (1-3). The structures and absolute configurations of new polyketides 1-3 were elucidated by extensive spectroscopic analyses, as well as comparisons between measured and calculated ECD spectra. Novel polyketides 1-3 and known 4, all bearing the heptaketide skeleton with a trans-fused decalin ring of 8-CH3 substitution, could significantly inhibit the radicle growth of Echinochloa crusgalli seedlings with a dose-dependent relationship. Especially at the concentration of 10 µg/mL, 1-4 exhibited the inhibition rates with 81.5% ± 2.0, 76.4% ± 0.8, 79.6% ± 1.1, and 80.0 ± 1.8%, respectively, even better than the commonly used synthetic herbicide of acetochlor with 76.1 ± 1.4%. Further greenhouse bioassay revealed that 4 showed pre-emergence herbicidal activity against E. crusgalli with the fresh-weight inhibition rate of 74.1% at a dosage of 400 g ai/ha, also better than acetochlor, while the other isolated metabolites (5-11) exhibited moderate herbicidal activities. The structure-activity differences of isolated polyketides indicated that the heptaketide skeleton, characterized by a trans-fused decalin ring with 8-CH3 substitution, should be the key factor of their herbicidal activities, which could give new insights for the bioherbicide developments.


Assuntos
Dicetopiperazinas/farmacologia , Herbicidas/farmacologia , Penicillium/química , Policetídeos/farmacologia , Dicetopiperazinas/metabolismo , Echinochloa/efeitos dos fármacos , Echinochloa/crescimento & desenvolvimento , Herbicidas/metabolismo , Estrutura Molecular , Penicillium/metabolismo , Policetídeos/metabolismo
3.
Stem Cell Res Ther ; 10(1): 384, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842997

RESUMO

BACKGROUND: MicroRNA (miR)-containing exosomes released by acute myeloid leukemia (AML) cells can be delivered into hematopoietic progenitor cells to suppress normal hematopoiesis. Herein, our study was performed to evaluate the effect of exosomal miR-4532 secreted by AML cells on hematopoiesis of hematopoietic stem cells. METHODS: Firstly, differentially expressed miRs related to AML were identified using microarray analysis. Subsequently, AML cell lines were collected, and CD34+ HSCs were isolated from healthy pregnant women. Then, miR-4532 expression was measured in AML cells and AML cell-derived exosomes and CD34+ HSCs, together with evaluation of the targeting relationship between miR-4532 and LDOC1. Then, AML cells were treated with miR-4532 inhibitor, and exosomes were separated from AML cells and co-cultured with CD34+ HSCs. Gain- and loss-function approaches were employed in CD34+ HSCs. Colony-forming units (CFU) and expression of dickkopf-1 (DKK1), a hematopoietic inhibiting factor associated with pathogenesis of AML, were determined in CD34+ HSCs, as well as the extents of JAK2 and STAT3 phosphorylation and LDOC1 expression. RESULTS: miR-4532 was found to be upregulated in AML cells and AML cell-derived exosomes, while being downregulated in CD34+ HSCs. In addition, exosomes released by AML cells targeted CD34+ HSCs to decrease the expression of CFU and increase the expression of DKK1. miR-4532 was delivered into CD34+ HSCs to target LDOC1 via AML cell-released exosomes. AML cell-derived exosomes containing miR-4532 inhibitor increased CFU but reduced DKK1 in CD34+ HSCs. Inhibition of miR-4532 or JAK2, or ectopic expression of LDOC1 upregulated CFU and downregulated DKK1 expression as well as the extents of JAK2 and STAT3 phosphorylation in CD34+ HSCs. CONCLUSION: In conclusion, AML cell-derived exosomes carrying miR-4532 repress normal HSC hematopoiesis via activation of the LDOC1-dependent STAT3 signaling pathway.

4.
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.

5.
BMC Cancer ; 19(1): 1125, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747911

RESUMO

BACKGROUND: Chemotherapy can improve the survival of patients with advanced gastric cancer. However, whether triplet chemotherapy can further improve the survival of patients with advanced gastric cancer compared with doublet chemotherapy remains controversial. This study reviewed and updated all published and eligible randomized controlled trials (RCTs) to compare the efficacy, prognosis, and toxicity of triplet chemotherapy with doublet chemotherapy in patients with advanced gastric cancer. METHODS: RCTs on first-line chemotherapy in advanced gastric cancer on PubMed, Embase, and the Cochrane Register of Controlled Trials and all abstracts from the annual meetings of the European Society for Medical Oncology (ESMO) and the American Society of Clinical Oncology conferences up to October 2018 were searched. The primary outcome was overall survival, while the secondary outcomes were progression-free survival (PFS), time to progress (TTP), objective response rate (ORR), and toxicity. RESULTS: Our analysis included 23 RCTs involving 4540 patients and 8 types of triplet and doublet chemotherapy regimens, and systematic review and meta-analysis revealed that triplet chemotherapy was superior compared with doublet chemotherapy in terms of improving median OS (HR = 0.92; 95% CI, 0.86-0.98; P = 0.02) and PFS (HR = 0.82; 95% CI, 0.69-0.97; P = 0.02) and TTP (HR = 0.92; 95% CI, 0.86-0.98; P = 0.02) and ORR (OR = 1.21; 95% CI, 1.12-1.31; P < 0.0001) among overall populations. Compared with doublet chemotherapy, subgroup analysis indicated that OS improved with fluoropyrimidine-based (HR = 0.80; 95% CI, 0.66-0.96; P = 0.02), platinum-based (HR = 0.75; 95% CI, 0.57-0.99; P = 0.04), and other drug-based triplet (HR = 0.79; 95% CI, 0.69-0.90; P = 0.0006) chemotherapies while not with anthracycline-based (HR = 0.70; 95% CI, 0.42-1.15; P = 0.16), mitomycin-based (HR = 0.81; 95% CI, 0.47-1.39; P = 0.44), taxane-based (HR = 0.91; 95% CI, 0.81-1.01; P = 0.07), and irinotecan-based triplet (HR = 1.01; 95% CI, 0.82-1.24; P = 0.94) chemotherapies. For different patients, compared with doublet chemotherapy, triplet chemotherapy improved OS (HR = 0.89; 95% CI, 0.81-0.99; P = 0.03) among Western patients but did not improve (HR = 0.96; 95% CI, 0.86-1.07; P = 0.47) that among Asian patients. CONCLUSIONS: Compared with doublet chemotherapy, triplet chemotherapy improved OS, PFS, TTP, and ORR in patients with advanced gastric cancer in the population overall, and improved OS in Western but not in Asian patients.

6.
Theranostics ; 9(26): 8409-8425, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754405

RESUMO

Introduction: Metastasis and drug resistance contribute substantially to the poor prognosis of colorectal cancer (CRC) patients. However, the epigenetic regulatory mechanisms by which CRC develops metastatic and drug-resistant characteristics remain unclear. This study aimed to investigate the role of miR-302a in the metastasis and molecular-targeted drug resistance of CRC and elucidate the underlying molecular mechanisms. Methods: miR-302a expression in CRC cell lines and patient tissue microarrays was analyzed by qPCR and fluorescence in situ hybridization. The roles of miR-302a in metastasis and cetuximab (CTX) resistance were evaluated both in vitro and in vivo. Bioinformatic prediction algorithms and luciferase reporter assays were performed to identify the miR-302a binding regions in the NFIB and CD44 3'-UTRs. A chromatin immunoprecipitation assay was performed to examine NFIB occupancy in the ITGA6 promoter region. Immunoblotting was performed to identify the EGFR-mediated pathways altered by miR-302a. Results: miR-302a expression was frequently reduced in CRC cells and tissues, especially in CTX-resistant cells and patient-derived xenografts. The decreased miR-302a levels correlated with poor overall CRC patient survival. miR-302a overexpression inhibited metastasis and restored CTX responsiveness in CRC cells, whereas miR-302a silencing exerted the opposite effects. NFIB and CD44 were identified as novel targets of miR-302a. miR-302a inhibited the metastasis-promoting effect of NFIB that physiologically activates ITGA6 transcription. miR-302a restored CTX responsiveness by suppressing CD44-induced cancer stem cell-like properties and EGFR-mediated MAPK and AKT signaling. These results are consistent with clinical observations indicating that miR-302a expression is inversely correlated with the expression of its targets in CRC specimens. Conclusions: Our findings show that miR-302a acts as a multifaceted regulator of CRC metastasis and CTX resistance by targeting NFIB and CD44, respectively. Our study implicates miR-302a as a candidate prognostic predictor and a therapeutic agent in CRC.

8.
R Soc Open Sci ; 6(8): 190580, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31598246

RESUMO

Proteins are the primary functional agents in all cellular processes, facilitating various functions such as enzymes and structure-forming or signal-transducing molecules. In this work, we report a fluorescent dye, PyMDI-Zn, which could specifically bind with proteins and provide a red-shifted fluorescent emission. The visual analysis of protein in sodium dodecyl sulfate-polyacrylamide gel electrophoresis could be realized in 5 min by using PyMDI-Zn as a light-up dye. Based on its cell penetration and low toxicity, PyMDI-Zn could also be applied to locate protein-rich regions and organelles in live cell imaging. Moreover, the direct protein quantitation can be realized based on PyMDI-Zn, providing a method of screening for food adulteration by nitrogen-rich compounds.

9.
Hum Factors ; : 18720819880646, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31618105

RESUMO

OBJECTIVE: To test the network disentangling model for explaining air traffic controllers' (ATCos) conflict resolution performance. The network rigidity index (NRI), and the steps to break the relational complexity network following a central-available-node-first rule, was hypothesized to explain the overall task demand, whereas marginal-effort-decrease rule was expected to explain the actual operational outcome. BACKGROUND: Understanding the conflict resolution process of ATCos is important for aviation safety and efficiency. However, linear models are insufficient. We proposed a new model that ATCos behavior can be largely considered as a process to break the relational complexity network, in which nodes represent the aircraft while links represent the cognitive complexity to understand the aircraft dyad relationship. METHOD: Twenty-one professional ATCos completed 27 conflict resolution scenarios that varied in the NRI and other control variables. Multilevel regression analyses were performed to understand the influence of the NRI on the number of interventions, mental workload, and unresolved rate. A cross-validation was performed to evaluate the predictive power of the model. RESULTS: NRI influenced ATCos intervention number in a curvilinear manner, which further leads to ATCo's mental workload. The deviance between the number of interventions and the NRI was strongly linked with unresolved rate. Cross-validation suggests that the models predictions are robust. CONCLUSION: The network disentangling model provides a useful theory-driven way to explain controllers' conflict resolution workload and other important performance outcomes such as intervention probability. APPLICATION: The proposed model can potentially be used for workload management, sector design, and intelligent decision support tool development.

10.
Hepatology ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529503

RESUMO

The poor prognosis of patients with hepatocellular carcinoma (HCC) is mainly attributed to its high rate of metastasis and recurrence. However, the molecular mechanisms underlying HCC metastasis need to be elucidated. The SRY-related HMG box (SOX) family proteins, which are a group of highly conserved transcription factors, play important roles in cancer initiation and progression. Here, we report a novel role of SOX18, a member of the SOX family, in promoting HCC invasion and metastasis. The elevated expression of SOX18 was positively correlated with poor tumor differentiation, higher TNM stage, and poor prognosis. The overexpression of SOX18 promoted HCC metastasis by upregulating metastasis-related genes, including fibroblast growth factor receptor 4 (FGFR4) and fms-related tyrosine kinase 4 (FLT4). Knockdown of both FGFR4 and FLT4 significantly decreased SOX18-mediated HCC invasion and metastasis, while the stable overexpression of FGFR4 and FLT4 reversed the decrease in cell invasion and metastasis that was induced by the inhibition of SOX18. Fibroblast growth factor 19 (FGF19), which is the ligand of FGFR4, upregulated SOX18 expression. A mechanistic investigation indicated that the upregulation of SOX18 that was mediated by the FGF19-FGFR4 pathway relied on the p-FRS2/p-GSK3ß/ß-catenin pathway. SOX18 knockdown significantly reduced FGF19-enhanced HCC invasion and metastasis. Furthermore, BLU9931, a specific FGFR4 inhibitor, significantly reduced the SOX18-mediated HCC invasion and metastasis. In human HCC tissues, SOX18 expression was positively correlated with FGF19, FGFR4 and FLT4 expression, and patients that coexpressed FGF19/SOX18, SOX18/FGFR4, or SOX18/FLT4 had the worst prognosis. CONCLUSION: We defined a FGF19-SOX18-FGFR4 positive feedback loop that played a pivotal role in HCC metastasis, and targeting this pathway may be a promising therapeutic option for the clinical management of HCC.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31394555

RESUMO

The p21-activated kinase (PAK) family of serine/threonine kinases plays a pivotal role in various human tumors, as supported by our previous report on the overexpressed PAK isoforms in non-small cell lung cancer (NSCLC). To better understand the role of PAKs in tumorigenesis, the authors examined PAK1 expression patterns and its significance in NSCLC. It was demonstrated by immunohistochemical staining that PAK1 was increased and localized in the cytoplasm in 151 of 207 cases. High levels of PAK1 expression correlated with a histologic type of tumor (squamous cell carcinoma), tumor node metastasis stage, and lymph nodal status. We also examined the biological role of PAK1 in lung cancer cell lines transfected with PAK1-small interfering RNA. Decreased expression of PAK1 inhibited lung cancer cell proliferation and invasion, which is the major cause of lung cancer malignancy. Downregulated expression of PAK1 hampered rapidly accelerated fibrosarcoma/mitogen-activated extracellular signal-regulated kinase/extracellular signal-regulated kinase pathway activity but did not affect Wnt/ß-catenin signaling. Our findings suggest that PAK1 is an important oncogene in NSCLC, as decreased expression of PAK1 inhibited the proliferation and invasion of NSCLC cells by blocking the ERK pathway. These results provide evidence for using PAK1 inhibition as potential anticancer therapy.

12.
Theranostics ; 9(13): 3723-3731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281509

RESUMO

Single nucleotide polymorphism (SNP) is the most abundant molecular marker associated with many physiologic and pathologic phenotypes. An isothermal, accurate and cost-effective SNP detection could make a great difference in point-of-care testing (POCT) or on-site diagnosis. However, there are two challenges, the expensive instrument and labor-intensive process, faced by the development of on-site SNP detection. We reported a novel SNP typing method based on the probe-enhanced loop-mediated isothermal amplification (PE-LAMP), which combines the oligonucleotide probe with a conventional LAMP to realize the SNP discrimination by analyzing the great discrepancy in amplification efficiency. Methods: We firstly constructed the genotyping method by combining the hybridization of the specific probe with the powerful amplification of LAMP. Then we validated the method by genotyping the SNP rs3741219 and we sought to realize one-step visualized typing. Finally, we applied the method to pharmacogenomic testing by genotyping CYP2C19*2 and MDR1 C3435T. Results: The PE-LAMP was successfully constructed to detect SNP and the sensitivity of our method is as low as 1000 copies of target DNA, which is sufficient to routine diagnosis. The high specificity in detecting mutant in the presence of excess wild-type allele could be achieved. It has shown good performance in helping predict the individual response of antiplatelet drug Clopidogrel through typing simply treated saliva samples. Conclusions: The proposed method is one-step, colorimetric, specific and sensitive enough to detect crudely treated samples, showing great potential in the pharmacogenomic study and POCT use.

13.
Theranostics ; 9(13): 3879-3902, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281520

RESUMO

Background: Metastasis is the major reason for high recurrence rates and poor survival among patients with colorectal cancer (CRC). However, the underlying molecular mechanism of CRC metastasis is unclear. This study aimed to investigate the role of forkhead box K2 (FOXK2), one of the most markedly increased FOX genes in CRC, and the mechanism by which it is deregulated in CRC metastasis. Methods: FOXK2 levels were analyzed in two independent human CRC cohorts (cohort I, n = 363; cohort II, n = 390). In vitro Transwell assays and in vivo lung and liver metastasis models were used to examine CRC cell migration, invasion and metastasis. Chromatin immunoprecipitation and luciferase reporter assays were used to measure the binding of transcription factors to the promoters of FOXK2, zinc finger E-box binding homeobox 1 (ZEB1) and epidermal growth factor receptor (EGFR). Cetuximab was utilized to treat FOXK2-mediated metastatic CRC. Results: FOXK2 was significantly upregulated in human CRC tissues, was correlated with more aggressive features and indicated a poor prognosis. FOXK2 overexpression promoted CRC migration, invasion and metastasis, while FOXK2 downregulation had the opposite effects. ZEB1 and EGFR were determined to be direct transcriptional targets of FOXK2 and were essential for FOXK2-mediated CRC metastasis. Moreover, activation of EGFR signaling by EGF enhanced FOXK2 expression via the extracellular regulated protein kinase (ERK) and nuclear factor (NF)-κB pathways. The EGFR monoclonal antibody cetuximab significantly inhibited FOXK2-promoted CRC metastasis. In clinical CRC tissues, FOXK2 expression was positively correlated with the expression of p65, ZEB1 and EGFR. CRC patients who coexpressed p65/FOXK2, FOXK2/ZEB1 and FOXK2/EGFR had poorer prognosis. Conclusions: FOXK2 serves as a prognostic biomarker in CRC. Cetuximab can block the EGF-NF-κB-FOXK2-EGFR feedback loop and suppress CRC metastasis.

14.
Nanoscale ; 11(24): 11765-11773, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31184359

RESUMO

Effective oxygen evolution reaction (OER) catalysts composed of Earth-abundant transition metals are crucial for sustainable energy conversion and storage. Metal-organic frameworks (MOFs) with tunable compositions are promising precursors for the fabrication of hollow and porous electrocatalysts. However, pulverous MOFs usually suffer from agglomeration during pyrolysis, greatly reducing the activity of their derived catalysts. In this work, Prussian blue analogue (PBA) arrays with hierarchical multidimensional architecture were directly grown on nickel foam (NF) using a template-oriented method. The subsequent calcination in air allowed for obtaining NixCo3-xO4 nanoplate arrays consisting of porous and hollow nanocubes. The derived bimetallic NixCo3-xO4/NF required only an overpotential of 287 mV to achieve a current density of 10 mA cm-2 in 1.0 M KOH solution, which is much lower than that of the monometallic NiO and the RuO2 benchmark. The 3D intersectional architecture of the NixCo3-xO4 nanoplates and the porous and hollow nanocube subunits contributed to the large specific surface area and reduced charge-transfer resistance of the NixCo3-xO4/NF electrode. Density functional theory (DFT) calculations and post-OER characterization revealed that the incorporated Co was the active sites and electrochemical active CoOOH intermediates were in situ formed during the OER. Our study provides a facile and efficient strategy for the rational design of MOF-derived materials towards effective and low-cost electrocatalysis.

15.
J Am Chem Soc ; 141(29): 11658-11666, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31241328

RESUMO

Buckminsterfullerene (C60) was adsorbed onto single-walled carbon nanotubes (SWCNTs) as an electron-acceptor to induce intermolecular charge-transfer with the SWCNTs, leading to a class of new metal-free C60-SWCNT electrocatalysts. For the first time, these newly developed C60-SWCNTs were demonstrated to act as trifunctional metal-free catalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) over a wide range of pH values, from acid to alkaline, with even higher electrocatalytic activities and better long-term stabilities than those of commercial Pt and RuO2 counterparts. Thus, the adsorption-induced intermolecular charge-transfer with the C60 electron-acceptor can provide a general approach to high-performance, metal-free, pH-universal carbon-based trifunctional metal-free electrocatalysts for water-splitting and beyond.

16.
Antonie Van Leeuwenhoek ; 112(11): 1645-1653, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31218499

RESUMO

A bacterial strain designated RZ03T was isolated from an intertidal sand sample from the Yellow Sea in China and characterised using a polyphasic taxonomic approach. Cells of strain RZ03T were observed to be Gram-stain negative, aerobic, and oxidase and catalase positive rods showing gliding motility and forming yellow colonies. Growth was found to occur at 7-30 °C (optimum, 25 °C), at pH 5.5-9.5 (optimum, pH 6.5-7.0) and with 0.5-5% NaCl (optimum, 1.5-2%). Phylogenetic analysis based on 16S rRNA gene sequences indicates that strain RZ03T clusters within members of the genus Flavivirga of the family Flavobacteriaceae and is closely related to the type strains Flavivirga amylovorans JCM 17112T and Flavivirga jejuensis JCM 17113T (97.9% and 97.5% similarity, respectively). The predominant cellular fatty acids are iso-C15:0, iso-C15:1 G, iso-C17:0 3-OH and iso-C15:0 3-OH and the major respiratory quinone is MK-6. Polar lipids include phosphatidylethanolamine, three unidentified aminolipids, an unidentified phospholipid and four unidentified lipids. The genome of strain RZ03T is 4.88 Mbp with a G+C content of 32.2 mol%. A total of 4152 genes are predicted, with 4052 protein-coding genes, 51 RNA genes and 49 pseudogenes. This polyphasic study suggests that strain RZ03T represents a novel species in the genus Flavivirga, for which the name Flavivirga rizhaonensis is proposed. The type strain is RZ03T(= KCTC 62833T = MCCC 1K03615T).

17.
Psychon Bull Rev ; 26(4): 1303-1309, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144134

RESUMO

It has been reported that human visual perception and attention are altered when the hands are nearby. Previous studies indicate that placing hands near stimuli enhances a subject's temporal sensitivity. However, few researchers have investigated the effect of hand proximity on reproducing temporal duration. Moreover, the delayed attentional disengagement and enhanced magnocellular visual processing theories provide two distinct predictions of the hand proximity effect on reproduced duration. Delayed attentional disengagement near hands will cause prolonged reproductions, whereas enhanced magnocellular visual processing predicts more accurate reproduction in the peri-hand space. The current study is the first to show that a short temporal duration is reproduced for a longer period near hands than far from hands in the dual-responding-hand condition, and this hand-proximity effect is attenuated in the single-responding-hand condition. These findings together with two further studies suggest that reproducing a temporal duration is modulated by hand proximity through prolonged attentional switch.


Assuntos
Atenção , Mãos , Percepção Espacial , Percepção do Tempo , Percepção Visual , Humanos
18.
Theranostics ; 9(6): 1572-1579, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31037124

RESUMO

Polymerase chain reaction (PCR) is the most commonly used technique in molecular biology and diagnostics. To achieve faster PCR reaction time, two strategies were employed by previous studies. That includes improving the thermal ramp rate by developing novel devices to reduce the time wasted on temperature transitions and cutting the holding time in every step, which could even lead to compromise in amplification efficiency. Hence the need to further improve the technique. Methods: A different way to achieve fast DNA amplification is developed by using the previously thought wasted time spent on heating and cooling the samples to finish the amplification. That means the holding time of the three procedures are omitted and this could be carried out on the ordinary PCR thermal cyclers. Results: 2/3 of the amplification time is easily saved, compared to the conventionally used method. Additionally, the reaction time could be further reduced by using longer primers with higher melting temperature (Tm). The record time of the "V" shape Polymerase chain reaction (VPCR) conducted on ordinary PCR machine for amplification of a 98 bp fragment is 8 min. Furthermore, VPCR still retains the merits of traditional PCR technique, including specificity, sensitivity, generality, and compatibility with quantitative detection. Conclusion: It is confirmed that the three procedures of PCR could be completed during the dynamic heating and cooling process when the cyclers are run at a moderate thermal ramp rate. As VPCR described here is based on the current PCR system, it could be implemented in any biological Lab immediately and provide great convenience to the people working in the field of life science and human health.

19.
Appl Environ Microbiol ; 85(14)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31053589

RESUMO

Candida albicans and Cryptococcus neoformans, human-pathogenic fungi found worldwide, are receiving increasing attention due to high morbidity and mortality in immunocompromised patients. In the present work, 110 fungus pairs were constructed by coculturing 16 wood-decaying basidiomycetes, among which coculture of Trametes robiniophila Murr and Pleurotus ostreatus was found to strongly inhibit pathogenic fungi through bioactivity-guided assays. A combination of metabolomics and molecular network analysis revealed that 44 features were either newly synthesized or produced at high levels in this coculture system and that 6 of the features that belonged to a family of novel and unusual linear sesterterpenes contributed to high activity with MICs of 1 to 32 µg/ml against pathogenic fungi. Furthermore, dynamic 13C-labeling analysis revealed an association between induced features and the corresponding fungi. Unusual sesterterpenes were 13C labeled only in P. ostreatus in a time course after stimulation by the coculture, suggesting that these sesterterpenes were synthesized by P. ostreatus instead of T. robiniophila Murr. Sesterterpene compounds 1 to 3 were renamed postrediene A to C. Real-time reverse transcription-quantitative PCR (RT-qPCR) analysis revealed that transcriptional levels of three genes encoding terpene synthase, farnesyl-diphosphate farnesyltransferase, and oxidase were found to be 8.2-fold, 88.7-fold, and 21.6-fold higher, respectively, in the coculture than in the monoculture, indicating that biosynthetic gene cluster 10 was most likely responsible for the synthesis of these sesterterpenes. A putative biosynthetic pathway of postrediene A to postrediene C was then proposed based on structures of sesterterpenes and molecular network analysis.IMPORTANCE A number of gene clusters involved in biosynthesis of secondary metabolites are presumably silent or expressed at low levels under conditions of standard laboratory cultivation, resulting in a large gap between the pool of discovered metabolites and genome capability. This work mimicked naturally occurring competition by construction of an artificial coculture of basidiomycete fungi for the identification of secondary metabolites with novel scaffolds and excellent bioactivity. Unusual linear sesterterpenes of postrediene A to C synthesized by P. ostreatus not only were promising lead drugs against human-pathogenic fungi but also highlighted a distinct pathway for sesterterpene biosynthesis in basidiomycetes. The current work provides an important basis for uncovering novel gene functions involved in sesterterpene synthesis and for gaining insights into the mechanism of silent gene activation in fungal defense.

20.
Cell Death Dis ; 10(3): 239, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858360

RESUMO

The sex-determining region Y (SRY)-box (SOX) family has a crucial role in carcinogenesis and cancer progression. However, the role of SOX12 and the mechanism by which it is dysregulated in colorectal cancer (CRC) remain unclear. Here we analyzed SOX12 expression patterns in two independent CRC cohorts (cohort I, n = 390; cohort II, n = 363) and found that SOX12 was significantly upregulated in CRC, indicating a poor prognosis in CRC patients. Overexpression of SOX12 promoted CRC cell proliferation and metastasis, whereas downregulation of SOX12 hampered CRC aggressiveness. Mechanistically, SOX12 facilitated asparagine synthesis by transactivating glutaminase (GLS), glutamic oxaloacetic transaminase 2 (GOT2), and asparagine synthetase (ASNS). Downregulation of GLS, GOT2, and ASNS blocked SOX12-mediated CRC cell proliferation and metastasis, whereas ectopic expression of GLS, GOT2, and ASNS attenuated the SOX12 knockdown-induced suppression of CRC progression. In addition, serial deletion, site-directed mutagenesis, luciferase reporter, and chromatin immunoprecipitation (ChIP) assays indicated that hypoxia-inducible factor 1α (HIF-1α) directly binds to the SOX12 promoter and induces SOX12 expression. Administration of L-asparaginase decreased SOX12-mediated tumor growth and metastasis. In human CRC samples, SOX12 expression positively correlated with GLS, GOT2, ASNS, and HIF-1α expression. Based on these results, SOX12 may serve as a prognostic biomarker and L-asparaginase represents a potential novel therapeutic agent for CRC.

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