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1.
PLoS One ; 15(1): e0227587, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923275

RESUMO

Diffusing fluid at a deep-sea hydrothermal vent creates rapid, acute physico-chemical gradients that correlate strongly with the distribution of the vent fauna. Two alvinocaridid shrimps, Alvinocaris longirostris and Shinkaicaris leurokolos occupy distinct microhabitats around these vents and exhibit different thermal preferences. S. leurokolos inhabits the central area closer to the active chimney, while A. longirostris inhabits the peripheral area. In this study, we screened candidate genes that might be involved in niche separation and microhabitat adaptation through comparative transcriptomics. The results showed that among the top 20% of overexpressed genes, gene families related to protein synthesis and structural components were much more abundant in S. leurokolos compared to A. longirostris. Moreover, 15 out of 25 genes involved in cellular carbohydrate metabolism were related to trehalose biosynthesis, versus 1 out of 5 in A. longirostris. Trehalose, a non-reducing disaccharide, is a multifunctional molecule and has been proven to act as a protectant responsible for thermotolerance in Saccharomyces cerevisiae. Putative positively selected genes involved in chitin metabolism and the immune system (lectin, serine protease and antimicrobial peptide) were enriched in S. leurokolos. In particular, one collagen and two serine proteases were found to have experienced strong positive selection. In addition, sulfotransferase-related genes were both overexpressed and positively selected in S. leurokolos. Finally, genes related to structural proteins, immune proteins and protectants were overexpressed or positively selected. These characteristics could represent adaptations of S. leurokolos to its microhabitat, which need to be confirmed by more evidence, such as data from large samples and different development stages of these alvinocaridid shrimps.

2.
Chemosphere ; 242: 125196, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896208

RESUMO

Lanzhou, an ex-heavily polluted city, was awarded "The Award for Today's Transformative Step" in 2015 World Climate Conference at Paris for its great efforts on air quality improvement since 2012. However, the health benefits from this improvement remain unclear. Therefore, we collected time-series data covering deaths, weather variables and air pollutants during the two periods (2004-2009, 2014-2017) and fitted single-pollutant models using the generalized additive models to evaluate the change of mortality risks associated with air pollutants in Lanzhou. Results showed that the annual average concentrations of respirable particulate matter (PM10) and sulfur dioxide (SO2) dropped by 19.28% and 66.29%, while the nitrogen dioxide (NO2) increased by 16.61% in 2014-2017 compared to 2004-2009. During the period 2004-2009, we found a 10-µg/m3 increase in PM10 (lag 2), SO2 (lag 0-5) and NO2 (lag 0-5) were associated with mortality increments of 0.12% (95% CI: 0.01, 0.22), 0.86% (95% CI: 0.42, 1.31) and 1.29% (95% CI: 0.70, 1.90), respectively. During the period 2014-2017, the association between PM10 and daily deaths was not significant, but we observed a 10-µg/m3 increase in SO2 (lag 0-5) and NO2 (lag 4) were related to mortality increments of 4.23% (95% CI: 1.82, 6.70) and 0.85% (95% CI: 0.19, 1.52), respectively. From 2004-2009 to 2014-2017, we observed markedly decline of mortality risk due to PM10, but not SO2 or NO2. In conclusion, the mortality risk of PM10 in Lanzhou has declined obviously after the substantially improved air quality due to the enforcement of air pollution controlling policies.

3.
J Neural Eng ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31899901

RESUMO

Objective- It is of great value to accurately localize innervation zones (IZs) for better diagnosing and treating neuromuscular diseases, but it is challenging to do so noninvasively from surface electromyography (sEMG) recordings because of the blurring/ distorting effect of the low conductive fat tissues. This study aimed to develop an innovative transcutaneous IZ imaging (TIZI) technique to precisely and efficiently localize the IZ distribution directly over the muscle surface in vivo from high-density sEMG recordings (HD-sEMG). Approach- The TIZI technique was implemented by incorporating HD-sEMG recording, signal decomposition, finite element analysis and inverse calculation. The performance of TIZI was evaluated on the flexor digitorum superficialis (FDS) muscle with simulated sEMG signal and experimental signal recorded from both healthy (n=3) and stroke participants (n=4). The accuracy of imaging was validated by both of the Pearson correlation coefficient (PCC) and localization error (LE) between the TIZI results and the 'true' IZ distribution. Main Results- In the simulation study, results have shown PCCs of 99.85±0.11%, 99.79±0.08%, 99.63±0.22% and 99.31±0.54% at the depth of 10, 15, 20 and 25 mm and SNR of 25 dB. PCCs of 98.74±1.78% and 97.82±1.20% were respectively obtained for experimental signals acquired from the healthy and spastic FDS muscles. The TIZI provided smaller LEs of 1.4±0.92 mm and 2.02 ± 1.3 mm, compared to LEs of 7.42±2.29 mm and 7.8±1.77 mm from skin observations in healthy and spastic FDS, respectively. Significance- Results have demonstrated the high performance of the proposed TIZI technique in transcutaneously imaging the IZ distribution of the skeletal muscles. The performance improvement can be attributed to the elimination of blurring/ distorting effect caused by the low conductive fat and high conductive skin tissues. TIZI may provide an advanced neurological tool for the clinical treatment of neuromuscular diseases, such as guiding botulinum neurotoxin injections in spasticity management.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31944974

RESUMO

In this paper, we investigate the robust dictionary learning (DL) to discover the hybrid salient low-rank and sparse representation in a factorized compressed space. A Joint Robust Factorization and Projective Dictionary Learning (J-RFDL) model is presented. The setting of J-RFDL aims at improving the data representations by enhancing the robustness to outliers and noise in data, encoding the reconstruction error more accurately and obtaining hybrid salient coefficients with accurate reconstruction ability. Specifically, J-RFDL performs the robust representation by DL in a factorized compressed space to eliminate the negative effects of noise and outliers on the results, which can also make the DL process efficient. To make the encoding process robust to noise in data, J-RFDL clearly uses sparse L2, 1-norm that can potentially minimize the factorization and reconstruction errors jointly by forcing rows of the reconstruction errors to be zeros. To deliver salient coefficients with good structures to reconstruct given data well, J-RFDL imposes the joint low-rank and sparse constraints on the embedded coefficients with a synthesis dictionary. Based on the hybrid salient coefficients, we also extend J-RFDL for the joint classification and propose a discriminative J-RFDL model, which can improve the discriminating abilities of learnt coefficients by minimizing the classification error jointly. Extensive experiments on public datasets demonstrate that our formulations can deliver superior performance over other state-of-the-art methods.

5.
Cancer Biomark ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31929144

RESUMO

BACKGROUND: Tumor-infiltrating immune cells are indispensable to the progression and prognosis of clear cell renal cell carcinoma (ccRCC). OBJECTIVE: The aim of this study was to explore the clinical implications of immune cell infiltrates in ccRCC. METHODS: The Cancer Genome Atlas (TCGA) database (N= 515) and E-MTAB-1980 cohort of patients (N= 101) were adopted to estimate the prognostic value of immune cell infiltration. Twenty-four types of immune cells were evaluated using single-sample gene set enrichment analysis. Cox regression analyses were conducted to develop an immune risk score. RESULTS: Survival analyses revealed that 13 genes significantly associated with the overall survival (OS). Furthermore, multivariate Cox analysis identified an immune risk score on the basis of mast cells, natural killer CD56bright cells, T helper 17 (Th17) cells, and Th2 cells. The immune risk score was associated with OS, with hazard ratios of 2.72 (95% CI 2.17-3.40) and 3.24 (95% CI 1.64-6.44) in TCGA and E-MTAB-1980 datasets, respectively. This immune risk score was significantly correlated with some immunotherapy-related biomarkers. CONCLUSIONS: We profiled a prognostic signature and established an immune risk score model for ccRCC, which could provide novel predictive markers for patients with ccRCC and an indicator for immunotherapy response measurement.

6.
EBioMedicine ; 51: 102566, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31901863

RESUMO

BACKGROUND: Early detection would improve upper gastrointestinal cancer prognosis. We aimed to identify serum protein biomarker for the detection of early-stage upper gastrointestinal cancer. METHODS: We performed a three-tiered study including 2028 participants from three medical centres. First, we applied two different antibody arrays to screen candidate serum proteins that increased in 20 patients with oesophageal squamous cell carcinoma (ESCC) compared with 20 normal controls. We then evaluated the selected protein by enzyme-linked immunosorbent assay in 1064 participants including 731 upper gastrointestinal cancer patients (287 ESCCs, 237 oesophagogastric junction adenocarcinomas (EJAs), and 207 stomach cancers) and 333 normal controls. The diagnostic value of the selected protein was finally validated in two independent cohorts of ESCC patients and controls (n=472 and 452, respectively). The receiver operating characteristic was used to calculate diagnostic accuracy. FINDINGS: Serum insulin-like growth factor binding protein-1 (IGFBP-1) identified in both antibody arrays showed significantly elevated levels in upper gastrointestinal cancers, compared with normal controls. Serum IGFBP-1 provided high diagnostic accuracy of early-stage ESCC, EJA, stomach and cancer (areas under the curve: 0·898, 0·936 and 0·864, respectively). This protein maintained diagnostic performance for early-stage ESCC in independent cohorts 1 and 2 (0·849 and 0·911, respectively). Additionally, serum levels of IGFBP-1 dropped significantly after surgical resection of primary tumours, compared with the corresponding pre-operative ESCC samples (p < 0·05). INTERPRETATION: Serum IGFBP-1 represents a promising diagnostic biomarker to detect early-stage upper gastrointestinal cancer.

7.
Science ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919128

RESUMO

Materials with high thermal conductivity (κ) are of technological importance and fundamental interest. We grew cubic boron nitride (cBN) crystals with controlled abundance of boron isotopes and measured κ over 1600 Wm-1 K-1 at room temperature in samples with enriched 10B or 11B. In comparison, we found the isotope enhancement of κ is considerably lower for boron phosphide and boron arsenide as the identical isotopic mass disorder becomes increasingly invisible to phonons. The ultrahigh κ in conjunction with its wide bandgap (6.2 eV) makes cBN a promising material for microelectronics thermal management, high-power electronics, and optoelectronics applications.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31935058

RESUMO

Collagen I (Col-I) is widely used in the fabrication of biomaterials due to its biocompatibility, however Col-I based biomaterials are susceptible to mechanical failure during handling, which limits their applicability to biomaterials. Chemical or physical treatment can improve the mechanical properties of collagen however, these processes can create issues of cytotoxicity or denaturation. We report here an alternative strategy to improve the stability and mechanical properties of Col-I while preserving its native structure, through thermal treatment in fluorous media. Thermal treatment of Col-I in fluorous solvent generates compact, stable films with significantly increased mechanical strength. Furthermore, the use of fluorous media significantly reduces the extent of swelling, rate of proteolytic degradation, and preserves the high cell biocompatibility.

9.
J Cell Physiol ; 235(1): 221-231, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31187497

RESUMO

The motility of mesenchymal stem cells (MSCs) is highly related to their homing in vivo, a critical issue in regenerative medicine. Our previous study indicated copper (Cu) might promote the recruitment of endogenous MSCs in canine esophagus defect model. In this study, we investigated the effect of Cu on the motility of bone marrow mesenchymal stem cells (BMSCs) and the underlying mechanism in vitro. Cu supplementation could enhance the motility of BMSCs, and upregulate the expression of hypoxia-inducible factor 1α (Hif1α) at the protein level, and upregulate the expression of rho family GTPase 3 (Rnd3) at messenger RNA and protein level. When Hif1α was silenced by small interfering RNA (siRNA), Cu-induced Rnd3 upregulation was blocked. When Rnd3 was silenced by siRNA, the motility of BMSCs was decreased with or without Cu supplementation, and Cu-induced cytoskeleton remodeling was neutralized. Furthermore, overexpression of Rnd3 also increased the motility of BMSCs and induced cytoskeleton remodeling. Overall, our results demonstrated that Cu enhanced BMSCs migration through, at least in part, cytoskeleton remodeling via Hif1α-dependent upregulation of Rnd3. This study provided an insight into the mechanism of the effect of Cu on the motility of BMSCs, and a theoretical foundation of applying Cu to improve the recruitment of BMSCs in tissue engineering and cytotherapy.

10.
Pathol Res Pract ; 216(1): 152793, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31870593

RESUMO

The class II trans-activator (CIITA) is the master regulator of the major histocompatibility complex (MHC) gene expression. CIITA mutations have been previously associated with several kinds of tumors, while the role of CIITA polymorphisms (rs3087456) in laryngeal squamous cell carcinoma (LSCC) is little known. We evaluate the link between CIITA polymorphisms and the existence of LSCC in patients. This study was conducted with 200 Chinese Han patients (LSCC) and 200 healthy control subjects. The association of CIITA genetic polymorphism rs3087456 with the risk of LSCC was assessed through pyrosequencing. The CIITA expression in LSCC tumor tissue and adjacent normal tissue was detected by immunohistochemistry (IHC) staining. The relationship between the genotype of rs3087456 in controls and in clinical pathology features in LSCC were analyzed, and in-silico analysis was also used for the CIITA gene. The in-silico analysis results showed that the CIITA gene is closely related to genes such as RFX5 and RFXAP. The IHC results showed that CIITA was highly expressed in LSCC tumor tissues, compared with the corresponding adjacent normal tissues. The AG, AG + AA, and A genotypes of rs3087456 of CIITA gene notably increased the risk of LSCC compared to the controls. Our study suggests that CIITA polymorphism (rs3087456) is associated with a higher risk of developing LSCC in a Chinese cohort.

11.
Pest Manag Sci ; 76(1): 215-226, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31149772

RESUMO

BACKGROUND: Cuticle penetration plays an important role as a mechanism of insecticide resistance, but the underlying molecular mechanism remains poorly understood. In Blattella germanica, the cytochrome P450 gene, CYP4G19, is overexpressed in a pyrethroid-resistant strain. Here, we investigated whether CYP4G19 is involved in the biosynthesis of hydrocarbons and further contributes to cuticular penetration resistance in B. germanica. RESULTS: Compared with the susceptible strain, pyrethroid-resistant cockroaches showed lower cuticular permeability with Eosin Y staining. Removal of epicuticular lipids, mainly nonpolar hydrocarbons, with a hexane wash intensified the cuticular permeability and decreased the resistance index of the resistant strain. CYP4G19 was predominately expressed in the abdominal integument and could be upregulated by desiccation stress or short exposure to beta-cypermethrin. Overexpression of CYP4G19 in the resistant strain was positively correlated with a higher level of cuticular hydrocarbons (CHCs). RNAi-mediated knockdown of CYP4G19 significantly decreased its expression and caused a reduction in CHCs. Meanwhile, CYP4G19 suppression resulted in a non-uniform array of the lipid layer, enhanced cuticle permeability, and compromised insecticide tolerance. CONCLUSION: Our findings confirm that CYP4G19 is involved in hydrocarbon production and appears to contribute to hydrocarbon-based penetration resistance in B. germanica. This study highlights the lipid-based penetration resistance, advancing our understanding of the molecular mechanism underlying P450-mediated cuticular penetration resistance in insects. © 2019 Society of Chemical Industry.

12.
J Cell Biochem ; 121(1): 353-362, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31219209

RESUMO

The critical role of long noncoding RNAs (lncRNAs) in the development of multiple cancers has been revealed either functioning as a tumor initiator or a cancer suppressor. A widely recognized OIP5 antisense RNA 1 (lncRNA OIP5-AS1) has been validated to be an essential regulator of the tumorigenesis of various malignancies. Whereas, the potential role and the exact mechanism of lncRNA OIP5-AS1 by which OIP5-AS1 mediates gastric cancer (GC) progression remains vague. Therefore, first our work probed its expression levels in GC cell lines and related normal cells by real-time quantitative polymerase chain reaction. The heightened level of OIP5-AS1 was detected in GC cell lines. In terms of its cellular effects, we performed a series of functional experiments and as presented in the assays, the proliferative potential and motility was diminished. However, more apoptotic cells were induced with the introduction of OIP5-AS1 silencing. Meanwhile, higher Nod-like receptor pyrin domain-containing protein 6 (NLRP6) and enhancer of zeste homolog 2 (EZH2) expression in the GC cells was monitored. Besides, OIP5-AS1 was disclosed to locate mainly in the nucleus. In terms of mechanism, OIP5-AS1 directly bound to EZH2 and obstructed NLRP6 expression, speeding up GC progression.

13.
ACS Appl Mater Interfaces ; 12(2): 2346-2353, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31877012

RESUMO

The development of advanced anode materials is crucial to enhance the performance of sodium-ion batteries (SIBs). In this study, SnSe2 nanoparticles chemically embedded in a carbon shell (SnSe2@C) were fabricated from Sn-organic frameworks and evaluated as an anode material for SIBs. The structural characterization demonstrated that there existed C-Sn chemical bonds between the SnSe2 nanoparticles and carbon shell, which could strongly anchor SnSe2 nanoparticles to the carbon shell. Such a structure can not only facilitate charge transfer but also ensure the structural stability of the SnSe2@C electrode. In addition, the carbon shell also helped in the dispersion of SnSe2 nanoparticles, thus offering more redox-active sites for Na+ storage. The as-prepared SnSe2@C nanocomposite could deliver good cycling stability and a superior rate capability of 324 mA h g-1 at 2 A g-1 for SIBs.

14.
J Phys Chem Lett ; 11(2): 485-491, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31885272

RESUMO

Two-dimensional (2D) nodal-loop (NL) semimetals have attracted tremendous attention for their abundant physics and potential device applications, whereas the realization of gapless NL semimetals robust against spin-orbit coupling (SOC) remains a big challenge. Recently, breakthroughs have been made with the realization of gapless NL semimetals in 2D half-metallic materials, where NLs were protected by a horizontal mirror plane symmetry. Here we first propose an alternative nonsymmorphic horizontal glide mirror plane symmetry which could protect the NLs in 2D materials. On the basis of comprehensive first-principles calculations and symmetry analysis, we found that the glide mirror symmetry together with intrinsic out-of-plane spin polarization can protect the NL against SOC in a half-metallic semimetal, namely, the MnNF monolayer. Moreover, we predict that the MnNF monolayer has strong anisotropic characteristics, tunable band structure by changing the magnetization direction, and 100% spin-polarized transport properties. Our work not only provides a novel 2D half-metallic semimetal with strong anisotropy but also broadens the scope of 2D nodal-loop materials.

16.
Anticancer Res ; 39(12): 6915-6921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810962

RESUMO

BACKGROUND/AIM: The present study aimed to investigate the role of Homebox B2 (HOXB2) in bladder cancer (BC). MATERIALS AND METHODS: The Cancer Genome Atlas (TCGA) dataset was used to analyse HOXB2 expression in BC. The influence of HOXB2 on the cellular functions of BC cells was determined in both HOXB2 knockdown and HOXB2 overexpressed BC cell lines using in vitro assays. RESULTS: HOXB2 mRNA was significantly upregulated in luminal infiltrated and luminal papillary subtypes of BC. Drug Metabolism Cytochrome P450 was significantly enriched in BCs expressing high levels of HOXB2. Knockdown of HOXB2 from EJ138 cells reduced growth, adhesion and invasion. In contrast, overexpression of HOXB2 in RT112 cells induced growth and adhesion of bladder cancer cells. CONCLUSION: Increased HOXB2 expression in papillary BC can promote cell growth and adhesion of BC cells. Drug Metabolism Cytochrome P450 pathway was enriched in BCs overexpressing HOXB2.

17.
Urol Oncol ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31812632

RESUMO

OBJECTIVES: To estimate the impact of peri-prostatic fat (PPF) measurements using preoperative magnetic resonance imaging on the prediction of prostate cancer (PCa) with transrectal ultrasound-guided biopsy. PATIENTS AND METHODS: We performed a retrospective 2-center study on 660 consecutive patients receiving transrectal ultrasound-guided biopsy-biopsy from June 2016 to October 2018. Pathologic and immunohistochemical characteristics were collected. PPF measurements including PPF area (PPFA) and PPFA to prostate area (PA) ratio (PPFA/PA) were assessed by preoperative staging magnetic resonance imaging. Clinical variables were correlated with Gleason score by using Spearman (ρ) correlation coefficients. Multivariable analysis was performed to identify independent predictors of PCa. The diagnostic performance was estimated using ROC curves. RESULTS: The Gleason score was significantly correlated with age (ρ = 0.114, P = 0.035), prostate-specific antigen (PSA) (ρ = 0.482, P < 0.001), PIRADS scoring (ρ = 0.403, P < 0.001) and PPFA/PA (ρ = 0.238, P < 0.001). Multivariate analysis revealed that PPFA/PA, age, digital rectal examination, family history of PCa, PSA, and PIRADS scoring were independently predictive of PCa. The ROC AUC to detect PCa or clinically significant PCa (CS-PCa; Gleason Score 3 + 4 or greater) improved with the addition of PPFA/PA (PCa: 0.93 vs. 0.89; CS-PCa: 0.92 vs. 0.90). CONCLUSION: PPFA/PA is an independent predictor for PCa along with age, digital rectal examination, family history of PCa, PSA, and PIRADS scoring. PPF measurements especially PPFA/PA may help detect PCa or CS-PCa, thus helping improve PCa risk stratification and screening to avoid unnecessary biopsies.

18.
Clin Infect Dis ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31813966

RESUMO

BACKGROUND: We estimated the time from HIV seroconversion to ART initiation in a population-based sample of people diagnosed with HIV during an era of expanding HIV testing and treatment efforts. METHODS: Applying CD4 depletion model parameters from seroconverter cohort data to our population-based sample, we related the square root of the first pre-treatment CD4 count to time of serconversion though a linear mixed model and estimated the time from seroconversion to diagnosis and ART initiation. RESULTS: Among 28,162 people diagnosed with HIV during 2006-2015, 89% initiated ART by June 2017. The median CD4 count at diagnosis increased from 326 (Interquartile range (IQR):132-504) to 390 (IQR:216-571) cells/µL from 2006-2015. The median time from estimated seroconversion to ART initiation decreased by 42% from 6.4 years (IQR:3.3-11.4) in 2006 to 3.7 years (IQR:0.5-8.3) in 2015. Contributing to the reduction in time to ART initiation, the time from estimated seroconversion to diagnosis decreased by 28%, from a median of 4.6 years (IQR:0.5-10.5) to 3.3 years (IQR:0-8.1) from 2006-2015, and the time from diagnosis to ART initiation reduced by 60%, from a median of 0.5 years (IQR:0.2-2.1) to 0.2 years (IQR:0.1-0.3) from 2006-2015. CONCLUSIONS: The estimated time from seroconversion to ART initiation was reduced in tandem with expanded HIV testing and treatment efforts. While the time from diagnosis to ART initiation decreased to a median of 0.2 years, the time from seroconversion to diagnosis was 3.3 years among people diagnosed in 2015, highlighting the need for more effective strategies for earlier HIV diagnosis.

19.
J Agric Food Chem ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31815467

RESUMO

Phytopathogenic fungi have been acknowledged as being an enormous threat in the agricultural system. In our search of new antifungal natural products, nine new halogenated cyclopentenones, bicolorins A-I (1-3, and 5-10), along with three known cyclopentenones (4, 11 and 12), were isolated from the endophytic fungus Saccharicola bicolor of Bergenia purpurascens by one strain-many compounds strategy. Their structures and absolute configurations were elucidated based on extensive spectroscopic analysis, X-ray crystallographic analysis, and TD-DFT-ECD calculations. Compounds 1-12 showed antifungal activities against five phytopathogenic fungi (Uromyces viciae-fabae, Pythium dissimile, Gibberella zeae, Aspergillus niger and Sclerotinia sclerotiorum). Especially, bicolorins B and D (2 and 5) exhibited strong antifungal activities against P. dissimile with the MIC values of 6.2 and 8.5 µg/mL, respectively, compared with the positive control cycloheximide (MIC of 8.6 µg/mL). Additionally, bicolorin D was proved to be potently antifungal against S. sclerotiorum in vitro and in vivo. This work provides an effective strategy for searching antifungal candidate agents.

20.
BMC Genomics ; 20(1): 954, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818245

RESUMO

BACKGROUND: Predatory mites (Acari: Phytoseiidae) are the most important beneficial arthropods used in augmentative biological pest control of protected crops around the world. However, the genomes of mites are far less well understood than those of insects and the evolutionary relationships among mite and other chelicerate orders are contested, with the enigmatic origin of mites at one of the centres in discussion of the evolution of Arachnida. RESULTS: We here report the 173 Mb nuclear genome (from 51.75 Gb pairs of Illumina reads) of the predatory mite, Neoseiulus cucumeris, a biocontrol agent against pests such as mites and thrips worldwide. We identified nearly 20.6 Mb (~ 11.93% of this genome) of repetitive sequences and annotated 18,735 protein-coding genes (a typical gene 2888 bp in size); the total length of protein-coding genes was about 50.55 Mb (29.2% of this assembly). About 37% (6981) of the genes are unique to N. cucumeris based on comparison with other arachnid genomes. Our phylogenomic analysis supported the monophyly of Acari, therefore rejecting the biphyletic origin of mites advocated by other studies based on limited gene fragments or few taxa in recent years. Our transcriptomic analyses of different life stages of N. cucumeris provide new insights into genes involved in its development. Putative genes involved in vitellogenesis, regulation of oviposition, sex determination, development of legs, signal perception, detoxification and stress-resistance, and innate immune systems are identified. CONCLUSIONS: Our genomics and developmental transcriptomics analyses of N. cucumeris provide invaluable resources for further research on the development, reproduction, and fitness of this economically important mite in particular and Arachnida in general.

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