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1.
Cancer Sci ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129914

RESUMO

MALAT1 is an oncogenic lncRNA that has been found to promote carcinogenesis and metastasis in many tumors. However, the underlying role of MALAT1 in the progression and metastasis of hepatocellular carcinoma (HCC) remains unclear. In this study, aberrantly elevated levels of MALAT1 were detected in both HCC specimens and cell lines. We found that knockdown of MALAT1 caused retardation in proliferation, migration and invasion both in vivo and in vitro. Mechanistic investigations showed that SNAI1 is a direct target of miR-22 and that MALAT1 modulates SNAI1 expression by acting as a competing endogenous RNA for miR-22. Inhibition of miR-22 restored SNAI1 expression suppressed by MALAT1 knockdown. Furthermore, MALAT1 facilitated the enrichment of EZH2 at the promoter region of miR-22 and E-cadherin, which was repressed by MALAT1 knockdown. MALAT1, cooperating with EZH2, positively regulated SNAI1 by repressing miR-22 and inhibiting E-cadherin expression, playing a vital role in epithelial to mesenchymal transition (EMT). In conclusion, our results reveal a mechanism by which MALAT1 promotes HCC progression and provides a potential target for HCC therapy.

2.
Drug Des Devel Ther ; 14: 845-854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161444

RESUMO

Background: Levodopa-carbidopa intestinal gel (LCIG) is a new type of administration that results in steadier levodopa plasma concentrations in advanced Parkinson's disease (PD) patients and effectively reduces poor mobility and dyskinesia. Methods: Electronic databases were searched up to January 1, 2018. The inclusion criteria for this review were as follows: LCIG vs oral medication in advanced PD patients. Results: Five trials, with a total of 198 patients, met all the inclusion criteria. The quality score of these studies ranged from 3 to 5. Two clinical trials showed that compared with oral medication, LCIG had a better treatment effect on on-time with troublesome dyskinesia (TSD) (p = 0.02) and on-time without TSD (p < 0.00001) in advanced PD patients. In addition, four of the 5 studies showed that the LCIG may have better efficacy than oral medication for improving the scores of the UPDRS, and two studies found that LCIG demonstrated better efficacy for improving the PDQ-39 scores. The video recording results indicated a potential decline in both dyskinesia and the "off" state in LCIG-treated patients. The incidence of adverse events was not significantly different between the LCIG and oral medication groups. Conclusion: Compared with oral treatment, LCIG exerts its effectiveness, mostly by reducing the time of on-time with TSD, increasing the time of on-time without TSD and scores of UPDRS and PDQ-39. It is suggesting that LCIG was likely to be a new type of administration used in clinical applications. However, due to methodological flaws, these findings should be viewed with caution, and more RCTs are needed in the field to complement our findings.

3.
Int J Colorectal Dis ; 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32179991

RESUMO

PURPOSE: Perineural invasion (PNI) is associated with poor prognosis in a variety of cancers. Our aim was to determine the clinicopathological factors associated with PNI in colorectal cancer (CRC) and its impact on patient survival. MATERIAL AND METHODS: The clinical data of 1412 patients diagnosed with CRC from July 2013 to July 2016 were retrospectively collected. PNI was determined based on hematoxylin-eosin staining. The relationships of PNI with various clinicopathological factors and prognosis were analyzed. RESULTS: The incidence of PNI in the entire cohort was 21.5%. PNI was significantly more common in patients with lower tumor differentiation, higher tumor stage, vascular invasion, TNM stage, tumor diameter, MMR/KRAS/NRAS/BRAF mutation, and more positive lymph nodes. Logistic regression analysis showed that T stage, vascular invasion, tumor diameter, and MMR were the main influencing factors of PNI. Cox regression analysis showed that poor tumor differentiation, N stage, TNM stage, PNI, and BRAF status were independent prognostic factors for OS. The OS, CSS, and PFS rate of the PNI (-) group was higher than that of the PNI (+) group, and the difference was statistically significant (P < 0.001). CONCLUSION: PNI in patients with colorectal cancer is significantly associated with T stage, TNM stage, vessel invasion, tumor diameter, MMR status, and BRAF mutation. PNI status is an independent prognostic factor for CRC. Assessing the postoperative PNI status may help predict prognosis and determine further treatment options for these patients.

4.
Proc Natl Acad Sci U S A ; 117(11): 5782-5790, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123087

RESUMO

Transfer RNAs (tRNAs) are products of RNA polymerase III (Pol III) and essential for mRNA translation and ultimately cell growth and proliferation. Whether and how individual tRNA genes are specifically regulated is not clear. Here, we report that SOX4, a well-known Pol II-dependent transcription factor that is critical for neurogenesis and reprogramming of somatic cells, also directly controls, unexpectedly, the expression of a subset of tRNA genes and therefore protein synthesis and proliferation of human glioblastoma cells. Genome-wide location analysis through chromatin immunoprecipitation-sequencing uncovers specific targeting of SOX4 to a subset of tRNA genes, including those for tRNAiMet Mechanistically, sequence-specific SOX4-binding impedes the recruitment of TATA box binding protein and Pol III to tRNA genes and thereby represses their expression. CRISPR/Cas9-mediated down-regulation of tRNAiMet greatly inhibits growth and proliferation of human glioblastoma cells. Conversely, ectopic tRNAiMet partially rescues SOX4-mediated repression of cell proliferation. Together, these results uncover a regulatory mode of individual tRNA genes to control cell behavior. Such regulation may coordinate codon usage and translation efficiency to meet the demands of diverse tissues and cell types, including cancer cells.

5.
Gene ; 737: 144411, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32006596

RESUMO

Long non-coding RNAs (lncRNAs) have been identified in cerebral ischemia-reperfusion (I/R) injury nowadays. Herein, we uncovered the function and underlying mechanism of the lncRNA Rian in cerebral I/R injury. The oxygen-glucose deprivation model in N2a cells was offered to mimic cerebral I/R injury in vitro. Trypan blue staining, reactive oxygen species (ROS) production, and caspase-3 activity were used to evaluate cell apoptosis. Then, middle cerebral artery occlusion was conducted to evaluate the function of lncRNA Rian in mice. Real-time PCR and western blotting were performed to determine the expression of lncRNA Rian, miR-144-3p, GATA binding protein 3 (GATA3), caspase-3, Bax, and Bcl-2. The results showed that both Rian and GATA3 were downregulated, and miR-144-3p was upregulated in cerebral I/R injury in vitro and in vivo. Overexpression of Rian could inhibit the cell apoptosis induced by oxygen-glucose deprivation. Furthermore, overexpression of Rian distinctly reduced the infarct size, and it also improved the neurological score. Overexpression of Rian could abolish miR-144-3p-mediated I/R injury in vitro and in vivo. Besides, GATA3 was the target of miR-144-3p and GATA3 could be regulated co-operatively by miR-144-3p and Rian. Consequently, these findings showed that the Rian/miR-144-3p/GATA3 axis is an essential signaling in cerebral I/R injury. The lncRNA Rian may serve as a potential target for novel treatment in patients with ischemic stroke.

6.
Biosci Rep ; 40(3)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32039453

RESUMO

OBJECTIVE: To investigate the specific function of long non-coding RNA HAL in serous ovarian cancer (SOC) and to further clarify the regulation of HAL on EMT pathway. MATERIALS AND METHODS: The expression of HAL and TWIST1 was detected by qRT-PCR. CCK8 assay, wound healing assay, transwell assay and flow cytometry were used to detect the HAL function on proliferation, migration, invasion and apoptosis in SOC cells. Western blot was used to calculate protein level of Vimentin, N-cadherin and E-cadherin. The effect of HAL on tumorigenesis of SOC was confirmed by xenograft nude mice model. RESULTS: HAL was significantly decreased in SOC tissues and cells. Overexpression of HAL inhibited the proliferation, migration and invasion of SKOV3 cells, but promoted apoptosis. Furthermore, overexpression of HAL decreased the mRNA and protein levels of TWIST1 via a binding between HAL and TWIST1. Forced expression of TWIST1 reversed the inhibitory role of HAL on SOC cells' migration and invasion. The in vivo tumor growth assay showed that HAL suppressed SOC tumorigenesis with inhibiting EMT pathway. CONCLUSIONS: Our research emphasized HAL acting as a tumor-inhibiting gene by regulating EMT signaling pathway, thus providing some novel experimental basis for clinical treatment of SOC.

7.
J Environ Manage ; 260: 110105, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941635

RESUMO

Bisphenol A (BPA) is a toxic environmental pollutant commonly found in wastewater. Using non-toxic materials and eco-friendly technology to remove this pollutant from wastewater presents multiple advantages. Treatment of wastewater with clay minerals has received growing interest because of the environment friendliness of these materials. Bentonite is a 2:1 layered phyllosilicate clay mineral that can support nano-metal catalysts. It can prevent the agglomeration of nano-metal catalysts and improve their activity. In this article, a green catalytic nano zero-valent iron/bentonite composite material (NZVI@bentonite) was synthesized via liquid-phase reduction. The average size of NZVI was approximately 40-50 nm. Good dispersion and low aggregation were observed when NZVI was loaded on the surface or embedded into the nanosheets of bentonite. Degradation of BPA, a harmful contaminant widely found in wastewater at relatively high levels, by NZVI@bentonite was then investigated and compared with that by pristine NZVI through batch Fenton-like reaction experiments. Compared with pristine NZVI and bentonite alone, the NZVI@bentonite showed a higher BPA degradation ratio and offered highly effective BPA degradation up to 450 mg/g in wastewater under optimum operating conditions. Adsorption coupled with the Fenton-like reaction was responsible for BPA degradation by NZVI@bentonite. This work extends the application of NZVI@bentonite as an effective green catalyst for BPA degradation in aqueous environments.


Assuntos
Bentonita , Poluentes Químicos da Água , Adsorção , Compostos Benzidrílicos , Ferro , Fenóis
8.
Br J Nutr ; 123(8): 841-848, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31964441

RESUMO

Human milk fat is specially tailored to supply the developing infant with adequate and balanced nutrients. The present study aimed to quantify the composition of fatty acids, tocopherols and carotenoids in human milk, with special emphasis on the lactational changes. Colostrum, transitional and mature milk samples were collected longitudinally from the same forty-two healthy, well-nourished Chinese mothers. Fatty acids were quantified by GC with carotenoids (carotenes and xanthophylls) and tocopherols (α-, γ-tocopherol) determined by HPLC. Total fatty acid (TFA) content increased from 15·09 g/l in colostrum to 32·57 g/l in mature milk with the percentages of DHA and arachidonic acid (ARA) decreased. The ratio of n-6:n-3 PUFA and ARA:DHA remained constant during lactation at about 11:1 and 1·3:1, respectively. Both α-tocopherol and γ-tocopherol decreased over lactation with the ratio of α-:γ-tocopherol declined significantly from 7·21:1 to 4·21:1 (P < 0·001). Carotenoids all dropped from colostrum to mature milk as the less polar carotenes dropped by 88·67 %, while xanthophylls only dropped by 35·92 %. Lutein was predominated in both transitional and mature milk carotenoids (51·64-52·49 %), while colostrum carotenoids were mainly composed of lycopene (32·83 %) and ß-carotene (30·78 %). The concentrations of tocopherols and xanthophylls but not carotenes were positively associated with TFA content in milk. These results suggested that colostrum and mature milk contained divergent lipid profiles and selective transfer mechanisms related to polarity might be involved. The present outcomes provide new insights for future breast-feeding studies, which also add in scientific evidences for the design of both initial and follow-on infant formulas.

9.
J Food Sci ; 85(2): 240-248, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31990038

RESUMO

The major polyphenol components from Stevia rebaudiana (Bertoni) leaves (PPS) are chlorogenic acids, a polyphenol family of esters, including hydroxycinnamic acids with quinic acid, which possesses excellent hydrophilic antioxidant activity and other therapeutic properties. As an abundant byproduct during production of steviol glycosides, the PPS would be a new antioxidantive food resource or additives applied in foods and drugs with antidiabetic function. Extracting PPS from S. rebaudiana (Bertoni) leaves together with steviol glycosides would be an economic process, which will change most operation process in current Stevia factories. The quantification of PPS needs to be unified for regulation. In view of the current regulation status of polyphenols and extracts from Stevia, the PPS would be ready to go to the market with few regulation barriers in the near future. This review will summarize the analysis, extraction, and some functional properties of PPS, such as antioxidant, antidiabetic, antimicrobial, anti-inflammatory, and anticancer.

11.
Talanta ; 210: 120596, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31987206

RESUMO

A zwitterionic three-dimensional (3D) metal-organic framework (MOF) of {[Cu(Cdcbp)(bipy)]·4H2O}n (1) has been synthesized and characterized (H3CdcbpBr = 3-carboxyl-(3,5-dicarboxybenzyl)-pyridinium bromide; bipy = 4,4'-bipyridine). MOF 1 exhibits a variety of structural traits, such as ligand conjugated, positively charged pyridinium center, and Cu(II) cations that collectively enable its efficient hybridization with the flexible, negatively charged, single-stranded, and thymine-rich (T-rich) DNA. The T-rich DNA is labeled with carboxyfluorescein (FAM) fluorescent probe (characterized as P-DNA), but the resultant MOF 1 - P-DNA hybrid (characterized as P-DNA@1) is non-emissive (off-state) because of the fluorescent quenching by MOF 1. The P-DNA@1 hybrid functions as an effective and selective sensor for Hg2+ due to the formation of rigid hairpin-like T-Hg2+-T double-stranded DNA (ds-DNA@Hg2+) which is subsequently ejected by MOF 1, triggering a recovery of the P-DNA fluorescence (on-state). Subsequent addition of biothiols further sequestrates Hg2+ from the ds-DNA@Hg2+ duplex driven by the stronger Hg-S coordination, thus release the P-DNA and, in turn, resorbed by MOF 1 to regain the initial hybrid (off-state). P-DNA@1 hybrid thus detects Hg2+ and biothiols sequentially via a fluorescence "off-on-off" mechanism. The limits of detection (LOD) for Hg2+, biothiols, including cysteine (Cys), glutathione (GSH) and homocysteine (Hcy) are 3.0, 14.2, 15.1 and 8.0 nM, respectively, with the detection time of 60 min for Hg2+, and instantaneous detection for all the three biothiols. The detection mechanism is further confirmed by circular dichroism (CD), fluorescence anisotropy (FA), binding constant and molecular simulation. This sequential detection of Hg2+ and biothiols counter-proofs the presence of each other and may shed light to the occurrence of related diseases, such as neurodegenerative disorders of Parkinson's disease (PD), and Alzheimer's disease (AD).

12.
Clin Respir J ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31905419

RESUMO

OBJECTIVE: To investigate the effect of non-small cell lung cancer (NSCLC) combined with Chronic Obstructive Pulmonary Disease (COPD) on prognosis, so as to provide help to clinical diagnosis and treatment. METHODS: PubMed, Web of Science and the Medline were used to retrieve studies reported from 1950 to 2019. If the study reported the prognosis of COPD with NSCLC, the study was included and the relevant information was extracted and the data analyzed. The standard mean deviation (SMD) of 95% confidence interval was used in this meta-analysis. RESULTS: A total of 851 data studies were reviewed for eligibility, eventually, 12 case-control studies were included in this systematic review and meta-analysis. The sample sizes for company's studies of NSCLC ranged from 85 to 10 378, with a total number of 14 164, including 2450 COPD and 9395 Non-COPD. Meta-analyses showed that concomitant COPD was associated with poorer OS compared with patients without COPD (Fixed: HR: 1.16; 95% CI: 1.08-1.25. Random: HR: 1.07; CI: 0.92-1.24), with a significant heterogeneity across studies (I2  = 45%, P = 0.04). CONCLUSION: Our study showed that patients with combined COPD had an impact on the prognosis and survival rate of SCLC patients.

13.
Biosens Bioelectron ; 153: 112019, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31989935

RESUMO

Adenosine triphosphate (ATP) plays a crucial role in energy metabolism and extracellular purinergic signaling. A 3D bimetallic Au/Pt nanoflowers decorated ATP microelectrode biosensor prepared by facile and effective template-free electrodeposition was firstly reported, realizing local detection of cellular ATP secretion. The ATP biosensor was developed by co-immobilization of glucose oxidase and hexokinase, exhibiting long-term stability (79.39 ± 9.15% of its initial value remained after 14 days at 4 °C) and high selectivity with a limit of detection down to 2.5 µM (S/N = 3). The resulting ATP biosensor was then used for direct in situ monitoring of ATP secreted from living cells (PC12) with the stimulation of high K+ solutions. The obtained current was about 21.6 ± 3.4 nA (N = 6), corresponding to 12.2 ± 2.8 µM ATP released from cells, right in the micromolar range and consistent with the suggested levels. The 3D bimetallic Au/Pt nanoflowers possess excellent catalytic activity and large electroactive surface area, contributing to enzymatic activity preservation and long-term stability. This work provides a promising platform for long-time monitoring of other neurotransmitters and secretions in cellular glycolysis and apoptosis processes in the future.

15.
Pest Manag Sci ; 76(3): 936-943, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31461216

RESUMO

BACKGROUND: RNA interference (RNAi) is widely used in entomological research for functional analysis of genes and is being considered as a new tool for insect pest management. Sri Lanka weevil (SLW) is a highly polyphagous pest of agronomically important plants, but currently only a few control methods are available for this insect. RESULTS: In the present study, we evaluated the stability of candidate reference genes ß-ACT, α-TUB, EF1-α, RPL12 and GAPDH, and identified EF1-α as the most reliable for gene expression normalization. Four target genes involved in different cellular processes, including Prosα2, RPS13, Snf7 and V-ATPase A were selected to evaluate whether RNAi response in SLW adults can be triggered by microinjection and oral feeding of their double-stranded RNAs (dsRNAs). Three days after injection of the dsRNAs for the target genes, their transcript levels were significantly reduced (up to 91.4%) when compared to the control. Additionally, weevils fed with the target dsRNAs showed significant decreases in gene transcript levels and significant mortality was observed in insects treated with Prosα2 and Snf7 dsRNAs (78.6 to 92.7%). CONCLUSION: Our data demonstrate that microinjection and feeding of dsRNA produce a strong RNAi response in SLW, indicating that RNAi-based strategies could be explored to develop a selective and environmentally safe control method against SLW. © 2019 Society of Chemical Industry.

16.
Int J Mol Med ; 45(1): 186-194, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746354

RESUMO

Senescence of cardiomyocytes is considered a key factor for the occurrence of doxorubicin (Dox)­associated cardiomyopathy. The NOD­like receptor family pyrin domain­containing 3 (NLRP3) inflammasome is reported to be involved in the process of cellular senescence. Furthermore, thioredoxin­interactive protein (TXNIP) is required for NLRP3 inflammasome activation and is considered to be a key component in the regulation of the pathogenesis of senescence. Studies have demonstrated that pretreatment with honokiol (Hnk) can alleviate Dox­induced cardiotoxicity. However, the impact of Hnk on cardiomyocyte senescence elicited by Dox and the underlying mechanisms remain unclear. The present study demonstrated that Hnk was able to prevent Dox­induced senescence of H9c2 cardiomyocytes, indicated by decreased senescence­associated ß­galactosidase (SA­ß­gal) staining, as well as decreased expression of p16INK4A and p21. Hnk also inhibited TXNIP expression and NLRP3 inflammasome activation in Dox­stimulated H9c2 cardiomyocytes. When TXNIP expression was enforced by adenovirus­mediated gene overexpression, the NLRP3 inflammasome was activated, which led to inhibition of the anti­inflammation and anti­senescence effects of Hnk on H9c2 cardiomyocytes under Dox treatment. Furthermore, adenovirus­mediated TXNIP­silencing inhibited the NLRP3 inflammasome. Consistently, TXNIP knockdown enhanced the anti­inflammation and anti­senescence effects of Hnk on H9c2 cardiomyocytes under Dox stimulation. In summary, Hnk was found to be effective in protecting cardiomyocytes against Dox­stimulated senescence. This protective effect was mediated via the inhibition of TXNIP expression and the subsequent suppression of the NLRP3 inflammasome. These results demonstrated that Hnk may be of value as a cardioprotective drug by inhibiting cardiomyocyte senescence.

17.
Nanoscale ; 12(2): 755-762, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31829368

RESUMO

Efficient photocatalytic conversion of CO2 into energy-rich chemicals is of great significance for both environmental conservation and alleviating the energy crisis. However, convenient synthesis of low-cost, durable and eco-friendly photocatalysts with a novel morphology or structure for highly selective photocatalytic CO2 reduction remains a challenge. Herein, Co3O4 hierarchical nanosheets were synthesized by calcination of novel cobalt metal-organic framework (MOF) nanosheets prepared by a facile oil bath method. In such Co MOF nanosheets, 1,4-naphthalenedicarboxylic acid was chosen as the organic linker, rather than the commonly used 2-methylimidazole for ZIF-67. After thermal treatment in air, the obtained Co3O4 inherited the 2D morphology of its MOF template and evolved into hierarchical nanosheets which were composed of small nanoparticles. Benefiting from the large surface area, abundant mesoporous structure and good capability towards the separation and transfer of photo-generated charge carriers induced by less internal oxygen vacancies, the Co3O4 hierarchical nanosheets showed a CO generation rate of 39.70 µmol h-1 in visible-light photocatalytic CO2 reduction, which was superior to that of Co3O4 nanoparticles and commercial Co3O4. What's more, a CO selectivity of 77.3% was achieved, which is among the highest of cobalt-based spinel oxide photocatalysts for CO2 conversion.

18.
Wound Repair Regen ; 28(1): 105-117, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31148320

RESUMO

Peritoneal adhesion occurs frequently after gastrointestinal/gynecological surgery. Tissue repair and regeneration are very important during this process. IL-22 is an important cytokine that is secreted from immune cells but functions on mesenchymal cells, such as mesothelial cells. The objective of this study was to investigate the roles of IL-22 and its regulators during adhesion formation. Postsurgical peritoneal drainage fluid from patients and rodent models was examined by enzyme-linked immunosorbent assay and fluorescence-activated cell sorting. It was observed that IL-22 expression in the abdominal cavity was rapidly induced 12 hours after surgery and then slowly decreased to a lower, steady level for up to 7 days after surgery. However, neutralizing IL-22 at the time point at which the highest level of expression was observed failed to reduce adhesion, but neutralizing IL-22 at a later time point, i.e., 3 days after surgery, prevented adhesion significantly. The IL-22 receptor was induced on the mesothelial membrane, and IL-22BP, an inhibitor of IL-22, was reduced 3 days after surgery. Furthermore, IFN-γ was identified to have the ability to induce IL-22R, and IL-18, which was induced by the infiltrating macrophages, was found to inhibit IL-22BP expression both in vivo and in vitro. Together, these data suggest that IL-22 may promote adhesion formation and that the regulation of IL-22, IL-22R, and IL-22BP may have therapeutic potential to prevent adhesion formation after surgery without disturbing the normal immune process.

19.
Ecotoxicol Environ Saf ; 187: 109790, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639642

RESUMO

We studied the effects of three organic acids (citric acid, tartaric acid and malic acid) on the biomass, photosynthetic pigment content and photosynthetic parameters of Salix variegata under Cd stress and observed the ultrastructure of mesophyll cells in each treatment. Cd stress significantly reduced photosynthesis by reducing the content of pigments and disrupting chloroplast structure, which consequently decreased the biomass. However, respective addition of three organic acids greatly increased the biomass of S. variegata under Cd stress. Among them, the effect of malic acid or tartaric acid on shoot and total biomass accumulation was greater than that of citric acid. The alleviation of biomass probably related with the photosynthetic process. Results revealed that treatment with each organic acid enhanced the net photosynthesis rate under Cd stress. Malic acid promoted plant growth and biomass by increasing the chlorophyll content and mitigating damage to the photosynthetic apparatus resulting from Cd stress. Tartaric acid had little impact on the photosynthetic pigment content, but it was important in mitigating the ultrastructural damage of plants caused by Cd. Addition of citric acid significantly increased the carotenoid as well as the number and volume of chloroplasts in mesophyll cells, while the mitigation of structural damage in the photosynthetic apparatus was weaker than that in tartaric acid or malic acid treatment. It is concluded that application of tartaric acid or malic acid is effective in increasing the growth potential of S. variegata under Cd stress and thus can be a promising approach for the phytoremediation of Cd-contaminated soil.


Assuntos
Cádmio/toxicidade , Malatos/farmacologia , Fotossíntese/efeitos dos fármacos , Salix/efeitos dos fármacos , Poluentes do Solo/toxicidade , Tartaratos/farmacologia , Biodegradação Ambiental , Disponibilidade Biológica , Biomassa , Cádmio/metabolismo , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , Salix/crescimento & desenvolvimento , Salix/ultraestrutura , Poluentes do Solo/metabolismo
20.
IEEE Trans Vis Comput Graph ; 26(1): 343-352, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31443019

RESUMO

Think-aloud protocols are widely used by user experience (UX) practitioners in usability testing to uncover issues in user interface design. It is often arduous to analyze large amounts of recorded think-aloud sessions and few UX practitioners have an opportunity to get a second perspective during their analysis due to time and resource constraints. Inspired by the recent research that shows subtle verbalization and speech patterns tend to occur when users encounter usability problems, we take the first step to design and evaluate an intelligent visual analytics tool that leverages such patterns to identify usability problem encounters and present them to UX practitioners to assist their analysis. We first conducted and recorded think-aloud sessions, and then extracted textual and acoustic features from the recordings and trained machine learning (ML) models to detect problem encounters. Next, we iteratively designed and developed a visual analytics tool, VisTA, which enables dynamic investigation of think-aloud sessions with a timeline visualization of ML predictions and input features. We conducted a between-subjects laboratory study to compare three conditions, i.e., VisTA, VisTASimple (no visualization of the ML's input features), and Baseline (no ML information at all), with 30 UX professionals. The findings show that UX professionals identified more problem encounters when using VisTA than Baseline by leveraging the problem visualization as an overview, anticipations, and anchors as well as the feature visualization as a means to understand what ML considers and omits. Our findings also provide insights into how they treated ML, dealt with (dis)agreement with ML, and reviewed the videos (i.e., play, pause, and rewind).

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