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2.
J Environ Manage ; 262: 110260, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32090883

RESUMO

In this study, multi-walled carbon nanotubes (MWCNTs) had been used to strengthen the removal of acid orange 7 (AO7) from the dyestuff wastewater by using foam fractionation. First, the surface modification of MWCNTs was performed by introducing hypochlorite groups (-OCl). The modified MWCNTs were characterized by using SEM, XRD, FTIR and Raman spectroscopy. Subsequently, the potential of modified MWCNTs as a novel collector for AO7 adsorption was examined. The adsorption conditions of modified MWCNTs towards AO7 were optimized by using response surface methodology (RSM) with a central composite design (CCD). The adsorption capacity of modified MWCNTs towards AO7 could reach 47.72 ± 0.79 mg·g-1 under the optimum conditions. The kinetics and the equilibrium adsorption data were analyzed by using different kinetic and isotherm models. According to the regression results, adsorption kinetics data were well described by pseudo-second order model, whereas adsorption isotherm data were best represented by Langmuir isotherm model. Finally, foam fractionation was performed with a batch mode. Under the suitable conditions of loading liquid volume 300 mL, modified MWCNTs dosage 180 mg, cetyltrimethylammonium bromide (CTAB) concentration 50 mg·L-1, AO7 concentration 30 mg·L-1, pore diameter of gas distributor 0.125 mm and air flow rate 100 mL·min-1, the removal percentage and enrichment ratio of AO7 were 91.23% and 6.17, respectively. The decolourization ratio of solution after foam fractionation was found to be 98.66%.

3.
Plant Sci ; 292: 110367, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32005375

RESUMO

Soybean mosaic virus (SMV) is a major pathogen causing yield loss. Developing soybean plants tolerant or resistant to SMV is important for mitigating the adverse effects of the viral infection. However, most studies have focused on the resistance to normal SMV strains. Thus, investigations of the resistance or tolerance to the novel recombinant SMV strain have been limited. To address the threat of the recombinant SMV, two soybean parent genotypes with contrasting reactions to the recombinant SMV and 211 F9:11 recombinant inbred lines were evaluated under artificial inoculation conditions. The JD12 plants are resistant to the recombinant SMV, whereas HT is highly tolerant, but still susceptible. Genetic analyses suggested that the resistance of JD12 is controlled by a single dominant gene and the tolerance is a quantitative trait. The QTL mapping results revealed one QTL (qTsmv-13) for resistance and two QTLs (qTsmv-2 and qTsmv-3) for tolerance. A comparison between known resistance genes and the QTLs identified in this study suggested that qTsmv-13 and qTsmv-2 may correspond to Rsv1 and Rsv4, respectively, whereas qTsmv-3 represents a newly identified QTL for SMV tolerance. We further delimited qTsmv-3 to an interval of approximately 86 kb with a map-based cloning strategy. Only two of five candidate genes, Glyma.03G00550 and Glyma.03G00570, varied between the parents. Additionally, Glyma.03G00550, which is a multidrug and toxic compound extrusion transporter gene, is the likely candidate gene for qTsmv-3. In summary, our research opens a new avenue for formulating strategies to breed soybean varieties tolerant to SMV.

4.
Eur J Cancer Care (Engl) ; : e13229, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32011788

RESUMO

OBJECTIVE: Cancer patients exhibit disparity in mortality risks across demographic divisions as well as insurance groups. The effects of macroeconomic environment also vary for such strata. This study analyses the gaps between mortality risks for male and female cancer patients with and without insurance and examines how such gaps transform over time with macroeconomic shifts. METHODS: Demographic, clinical and treatment records of 45,750 melanoma and 91,157 lung cancer patients diagnosed in 2007-2009 and 2011-2013 were extracted from Surveillance, Epidemiology and End Results (SEER) database. Kaplan-Meier test was applied to ascertain survival probability of each insurance group, while Cox proportional hazard model was used to assess relative mortality risk for Medicaid and uninsured patients, for the whole data as well as separately for both time periods and genders. RESULTS: Both the hazard ratios and change thereof over time are greater for female patients without insurance, than for male patients. More than any insurance-gender subgroup, uninsured female patients of melanoma have much increased hazard ratios, from 1.41 [95% confidence interval (CI), 1.04-1.92] to 2.22 [95% CI, 1.67-2.94]. CONCLUSION: Despite diagnostic improvements and technology advancements, the adverse effects of macroeconomic crisis are associated with increased relative mortality risks for cancer patients without insurance, more for women than men.

5.
Metabolomics ; 16(3): 29, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32095917

RESUMO

INTRODUCTION: Colorectal cancer (CRC) remains an incurable disease. Previous metabolomic studies show that metabolic signatures in plasma distinguish CRC patients from healthy controls. Chronic enteritis (CE) represents a risk factor for CRC, with a 20 fold greater incidence than in healthy individuals. However, no studies have performed metabolomic profiling to investigate CRC biomarkers in CE. OBJECTIVE: Our aims were to identify metabolomic signatures in CRC and CE and to search for blood-derived metabolite biomarkers distinguishing CRC from CE, especially early-stage biomarkers. METHODS: In this case-control study, 612 subjects were prospectively recruited between May 2015 and May 2016, and including 539 CRC patients (stage I, 102 cases; stage II, 259 cases; stage III, 178 cases) and 73 CE patients. Untargeted metabolomics was performed to identify CRC-related metabolic signatures in CE. RESULTS: Five pathways were significantly enriched based on 153 differential metabolites between CRC and CE. 16 biomarkers were identified for diagnosis of CRC from CE and for guiding CRC staging. The AUC value for CRC diagnosis in the external validation set was 0.85. Good diagnostic performances were also achieved for early-stage CRC (stage I and stage II), with an AUC value of 0.84. The biomarker panel could also stage CRC patients, with an AUC of 0.72 distinguishing stage I from stage II CRC and AUC of 0.74 distinguishing stage II from stage III CRC. CONCLUSIONS: The identified metabolic biomarkers exhibit promising properties for CRC monitoring in CE patients and are superior to commonly used clinical biomarkers (CEA and CA19-9).

6.
Sch Psychol ; 35(2): 158-169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32105141

RESUMO

Although the psychological impacts of cyberbullying victimization (CBV) have been documented, research is inconclusive about the role of contextual factors in the association between CBV and student engagement. Sampling 16,237 adolescents from 43 schools in Delaware, we used multilevel modeling to test how CBV was associated with emotional and cognitive-behavioral engagement at both the student and school levels, with the control for demographic factors and traditional bullying victimization (TBV). We also examined the moderating effects of school climate and grade level on the association between CBV and student engagement. CBV had a small but significant positive association with emotional engagement and a small but significant negative association with cognitive-behavioral engagement. School-level climate intensified the negative association between student-level CBV and cognitive-behavioral engagement and mitigated the positive association between student-level school climate and emotional engagement. The positive association between CBV and emotional engagement was stronger for high school than middle school students, whereas the negative association between CBV and cognitive-behavioral engagement was stronger for middle than high school students. The findings support the promotive role of positive school climate in student engagement promotion. The findings also support the healthy context paradox, which suggests that bullying victims' engagement in schools may be exacerbated in a social context with positive school climate perceived by the group members. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

7.
Biol Reprod ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31965149

RESUMO

Characterization of the molecular factors regulating early embryonic development and their functional mechanisms is critical for understanding the causes of early pregnancy loss in monotocous species (cattle, human). We previously characterized a stage specific functional role of follistatin, a TGF-beta superfamily binding protein, in promoting early embryonic development in cattle. The mechanism by which follistatin mediates these embryotropic effects is not precisely known as follistatin actions in cattle embryos are independent of its classically known activin inhibition activity. Apart from activin, follistatin is known to bind and modulate the activity of the BMPs which signal through SMAD1/5 pathway and regulate several aspects of early embryogenesis in other mammalian species. Present study was designed to characterize the activity and functional requirement of BMP signaling during bovine early embryonic development and to investigate if follistatin involves BMP signaling for its stage specific embryotropic actions. Immunostaining and Western blot analysis demonstrated that SMAD1/5 signaling is activated after embryonic genome activation in bovine embryos. However, d1-3 follistatin treatment reduced the abundance of phosphorylated SMAD1/5 in cultured embryos. Inhibition of active SMAD1/5 signaling (8-16 cell to blastocyst) using pharmacological inhibitors and/or lentiviral mediated inhibitory SMAD6 overexpression showed that SMAD1/5 signaling is required for blastocyst production, first cell lineage determination as well as mRNA and protein regulation of TE (CDX2) cell markers. SMAD1/5 signaling was also found to be essential for embryotropic actions of follistatin during d4-7 but not d1-3 of embryo development suggesting a role for follistatin in regulation of SMAD1/5 signaling in bovine embryos.

8.
Zhongguo Zhen Jiu ; 40(1): 96-102, 2020 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-31930907

RESUMO

The problems of the syndrome differentiation of migraine in acupuncture treatment were collected, e.g. inconsistency of syndrome differentiation, unclear staging of syndrome differentiation, lack of standardization in comparison between syndrome differentiation and non-differentiation, insufficient research on the factors of syndrome differentiation. In view of the exiting problems, focusing on two aspects of migraine, namely syndrome differentiation and acupuncture effect, the clinical treatment and research are conducted in migraine treated with acupuncture based on syndrome differentiation. It is believed that the comprehensive observation of the relationship between syndrome differentiation and acupuncture effect, as well as the analysis of the relevant factors of syndrome differentiation of migraine should be the focus in future research.


Assuntos
Terapia por Acupuntura , Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/terapia , Resultado do Tratamento
9.
Dev Comp Immunol ; 105: 103602, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31918206

RESUMO

The blood clam Tegillarca granosa is a member of the most economically important bivalve mollusk species in the Asia-Pacific region. T. granosa entirely depends on innate immunity for pathogen defense. However, there are very few reports on the immune responses of T. granosa to various pathogens. In our study, we cloned and characterized an ERK homolog from T. granosa, which was defined as TgERK. The full-length cDNA sequence of TgERK was 1644 bp in length and encoded a conserved S_TKc domain (residues 21-309) in the N terminus. The TgERK mRNA was universally expressed in all examined tissues, with the highest expression level found in hemocytes. Lipopolysaccharide (LPS) and Vibrio alginolyticus challenges strongly enhanced the expression of ERK in T. granosa, which was consistent with the results of an in vitro challenge study with cultured T. granosa hemocytes. Pathogen invasion also upregulated the expression of downstream genes in the ERK signaling pathway, such as CREB, c-Fos and SIRT1. Moreover, TgERK knockdown resulted in decreased expression of these downstream genes. Inhibition of ERK by its inhibitor U0126 decreased T. granosa hemocyte viability in a dose-dependent manner. Taken together, our results demonstrated that TgERK was a crucial regulator of the immune response to pathogen invasion, which indicated new knowledge of hemocyte immunity in T. granosa and provided a novel key molecule in immune regulation for controlling diseases in T. granosa aquaculture.

10.
Environ Sci Pollut Res Int ; 27(7): 7729-7735, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904101

RESUMO

Somatic cell nuclear transfer (SCNT) is a valuable technology tool with various uses in transgenic animals, regenerative medicine, and stem cell research. However, the efficiency of SCNT embryos appears to have poor developmental competency. Environmental issues may adversely affect SCNT embryos in buffalo. Thereafter, the present study aimed to explore the effect of season on the maturation of buffalo oocytes and subsequent developmental capability after parthenogenetic activation and SCNT in buffalo. Buffalo oocytes (n = 6353) were collected from local slaughterhouse at various seasons; spring (March-April), summer (May-August), autumn (September-November), and winter (December-January). A significant increase (p < 0.05) was recorded in the maturation rate (57.07%) at autumn compared with spring, summer, and winter (50.46, 50.93, and 50.66%, respectively). No significant differences were recorded in the fusion and the cleavage rates among all seasons. Blastocyst development rate was higher (p < 0.05) in autumn and winter (16.52 ± 8.45% and 15.98 ± 7.17%, respectively) than in spring and summer (9.47 ± 6.71% and 10.84 ± 6.58%, respectively) seasons. It could be concluded that the season had a significant effect on oocyte development competence which can be used for SCNT in buffalo.

11.
Sch Psychol ; 35(1): 99-109, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31804101

RESUMO

Although multiple cross-sectional studies have supported moral disengagement and school climate being associated with bullying perpetration, few have examined how these 3 factors interact with each other over time. Guided by the social-ecological theory and social-cognitive theory, a multilevel approach was used to examine the longitudinal associations between students' moral disengagement and bullying perpetration and the moderating effect of students' perceptions of school climate in the longitudinal association across 18 months. The main effects of moral disengagement and perceived school climate and the effects of their interaction on bullying perpetration were explored at the between-person, within-person, and across between-person and within-person levels. Participants were 2,997 adolescents (Mage = 14.9 years, SD = 1.53; 49.7% male) from 6 secondary schools in Southwest China. At the between-person level, students with higher moral disengagement and more negative perceptions of school climate perpetrated more bullying than those with lower moral disengagement and more positive perceptions of school climate. At the within-person level, students with high moral disengagement and negative perceptions of school climate had high levels of bullying perpetration over time. Moreover, significant between-person, within-person, and cross-level interactions revealed that the association between moral disengagement and bullying perpetration was weaker and nonsignificant for students with more positive perceptions of school climate. Findings indicated a buffering effect of students' perceptions of positive school climate in the longitudinal association between moral disengagement and bullying perpetration. Implications for school-based individualized bullying intervention were discussed. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

12.
Int J Oncol ; 56(1): 69-84, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31789398

RESUMO

The present study aimed to evaluate the correlation of integrin α7 (ITGA7) with clinicopathological characteristics and overall survival (OS) in patients with tongue squamous cell carcinoma (TSCC), and to investigate the effect of ITGA7 knockdown on proliferation, apoptosis and stemness of TSCC cells in vitro. ITGA7 expression was measured in tumor tissues and paired adjacent normal tissues from 60 patients with TSCC using immunohistochemistry. ITGA7 expression in human TSCC cell lines and normal oral keratinocytes was measured using quantitative PCR and western blotting. Lentiviruses carrying short hairpin (sh) RNA targeting ITGA7 were used to knockdown its expression in CAL­27 and HSC­4 cells, and then proliferation, apoptosis and stemness were measured. In addition, CAL­27 and HSC­4 cancer stem cells (CSCs) were constructed and their ITGA7 expression was measured. The results demonstrated that ITGA7 was upregulated in the tumor tissues compared with the paired adjacent tissues, and its high expression was correlated with worse pathological grade, N stage, TNM stage and OS. In vitro, ITGA7 expression levels were demonstrated to be increased in the TSCC CAL­27, SCC­9, HSC­4 and SCC­25 cell lines compared to the normal HOK cell line. In CAL­27 and HSC­4 cells, ITGA7 knockdown inhibited cell proliferation, promoted apoptosis, increased CD24 expression, decreased CD44 and CD133 expression, reduced drug resistance to cisplatin and attenuated sphere formation efficiency. Finally, ITGA7 expression levels were greatly elevated in CAL­27 and HSC­4 CSCs compared with parental CAL­27 and HSC­4 cells. In conclusion, ITGA7 knockdown inhibited tumor cell proliferation and stemness in TSCC cells. These findings indicated that ITGA7 might serve as a potential marker for CSCs and may correlate with worse clinical features and prognosis in TSCC.

13.
G3 (Bethesda) ; 10(2): 839-848, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31792004

RESUMO

A trispecific hybrid, MTP (hereafter called tripsazea), was developed from intergeneric crosses involving tetraploid Zea mays (2n = 4x = 40, genome: MMMM), tetraploid Tripsacum dactyloides (2n = 4x = 72, TTTT), and tetraploid Z perennis (2n = 4x = 40, PPPP). On crossing maize-Tripsacum (2n = 4x = 56, MMTT) with Z perennis, 37 progenies with varying chromosome numbers (36-74) were obtained, and a special one (i.e., tripsazea) possessing 2n = 74 chromosomes was generated. Tripsazea is perennial and expresses phenotypic characteristics affected by its progenitor parent. Flow cytometry analysis of tripsazea and its parents showed that tripsazea underwent DNA sequence elimination during allohexaploidization. Of all the chromosomes in diakinesis I, 18.42% participated in heterogenetic pairing, including 16.43% between the M- and P-genomes, 1.59% between the M- and T-genomes, and 0.39% in T- and P-genome pairing. Tripsazea is male sterile and partly female fertile. In comparison with previously synthesized trihybrids containing maize, Tripsacum and teosinte, tripsazea has a higher chromosome number, higher seed setting rate, and vegetative propagation ability of stand and stem. However, few trihybrids possess these valuable traits at the same time. The potential of tripsazea is discussed with respect to the deployment of the genetic bridge for maize improvement and forage breeding.

14.
Prep Biochem Biotechnol ; 50(1): 37-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31453755

RESUMO

Casein was the major protein in the milk of mammals and it was massively lost in the discharged wastewater during dairy product manufacture. This work was aimed at recovering casein from the dairy wastewater by using foam fractionation. In order to improve the foam stability, xanthan gum was used as the foam stabilizer based on the association between protein and polysaccharide. The results of the scanning electron microscope (SEM) and fluorescence emission spectrum suggested that casein could be associated with xanthan gum primarily through electrostatic attraction, which was significantly affected by pH. Moreover, the introduction of xanthan gum had a marked impact on the surface tension, foam ability, foam stability, turbidity, zeta potential and average particle size of casein dispersion. Foam fractionation was performed under the suitable operation condition of pH 6.0, loading liquid volume 400 mL, amount ratio of casein and xanthan gum 1:2, volumetric airflow rate 100 mL/min and pore diameter of gas distributor 0.180 mm. The enrichment ratio and the recovery percentage of casein reached as high as 16.81 and 86.51%, respectively. This work is expected to provide a cost-effective method to recover the trace desired material through improving foam stability based on intermolecular forces.Research highlightsFoam fractionation has been proposed to recover casein from dairy wastewater.Xanthan gum has been used to improve the foam stability of casein.The main interaction between casein and xanthan gum was an electrostatic attraction.Xanthan gum contributed to weakening the flowability of interstitial liquid.


Assuntos
Caseínas/isolamento & purificação , Polissacarídeos Bacterianos/química , Águas Residuárias/química , Animais , Fracionamento Químico/métodos , Indústria de Laticínios/métodos , Leite/química , Tamanho da Partícula
15.
Environ Sci Pollut Res Int ; 27(2): 1697-1709, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31755059

RESUMO

To reveal the adsorption mechanism of sediment to antibiotics with the presence of dissolved organic matter (DOM), batch experiments were carried out by oxytetracycline (OTC) on sediments with decayed plants (PDOM) and composted chicken manure (MDOM), and the zeta potential in the system before and after adsorption was measured. Results showed that the PDOM promoted the adsorption process, while the MDOM inhibited the adsorption. Adding PDOM, the change of zeta potential (Δζ) increased by 40.08% for first terrace sediments (FT) and 63.98% for riverbed sediments (RB), respectively; meanwhile, MDOM decreased by 20.04% for FT and 28.39% for RB, respectively. The results of kinetic fitting models of replacing the adsorption amount with Δζ were consistent with the initial. It indicated that there was a positive correlation between the adsorption amount and Δζ, and the zeta potential can be used to quickly judge the degree of adsorption process. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory describes the interactions of sediment particles. In terms of adsorption amount, zeta potential (absolute value) and total interaction energy all followed the order: RB > FT, RB-PDOM > FT-PDOM, and RB-MDOM > FT-MDOM. The more negative the zeta potential is, the better the dispersion of the particles is. Stronger repulsion is more conducive to adsorbing positively charged OTC. The site energy distribution theory further explained that the distribution of adsorption site in the various states of sediments increased while adding the PDOM and decreased while adding the MDOM.

16.
Waste Manag ; 101: 200-209, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622865

RESUMO

Present work was focused on recovering gold (Au) from the printed circuit boards (PCBs) of discarded cellphone by bioleaching assisted continuous foam fractionation. First, the cyanide-producing strains of Pseudomonas putida and Bacillus megaterium were co-cultured in order to supply a high cyanide concentration in the nutrient solution for mobilizing Au from waste PCBs (WPCBs). Bioleaching conditions were optimized by using response surface methodology. Under the suitable bioleaching conditions of pH of 10.0, pulp density of 5 g/L and leaching time of 34 h, the Au mobilization percentage was 83.59%. The leaching liquor with an Au concentration of 1.34 mg/L could be used as the feeding solution of continuous foam fractionation after removing solid particles and cell biomass. In order to strengthen foam drainage, a novel internal component of foam fractionation column was developed. Under the suitable operation conditions of CTAB concentration of 0.2 g/L, volumetric air flow rate of 100 mL/min and feed flow rate of 10 mL/min, the enrichment ratio and recovery percentage of Au were 43.62 and 87.46%, respectively. This study is expected to provide an effective strategy to recover Au from WPCBs, and to supplement the depleting natural resources.


Assuntos
Telefone Celular , Resíduo Eletrônico , Cobre , Ouro , Reciclagem
17.
Proc Natl Acad Sci U S A ; 117(1): 271-277, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31848246

RESUMO

Brown planthopper (BPH) is one of the most destructive insects affecting rice (Oryza sativa L.) production. Phenylalanine ammonia-lyase (PAL) is a key enzyme involved in plant defense against pathogens, but the role of PAL in insect resistance is still poorly understood. Here we show that expression of the majority of PALs in rice is significantly induced by BPH feeding. Knockdown of OsPALs significantly reduces BPH resistance, whereas overexpression of OsPAL8 in a susceptible rice cultivar significantly enhances its BPH resistance. We found that OsPALs mediate resistance to BPH by regulating the biosynthesis and accumulation of salicylic acid and lignin. Furthermore, we show that expression of OsPAL6 and OsPAL8 in response to BPH attack is directly up-regulated by OsMYB30, an R2R3 MYB transcription factor. Taken together, our results demonstrate that the phenylpropanoid pathway plays an important role in BPH resistance response, and provide valuable targets for genetic improvement of BPH resistance in rice.

18.
Front Plant Sci ; 10: 1445, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803203

RESUMO

Soybean is a major source of protein for human consumption and animal feed. Releasing new cultivars with high nutritional value is one of the major goals in soybean breeding. To achieve this goal, genome-wide association studies of seed amino acid contents were conducted based on 249 soybean accessions from China, US, Japan, and South Korea. The accessions were evaluated for 15 amino acids and genotyped by sequencing. Significant genetic variation was observed for amino acids among the accessions. Among the 231 single nucleotide polymorphisms (SNPs) significantly associated with variations in amino acid contents, fifteen SNPs localized near 14 candidate genes involving in amino acid metabolism. The amino acids were classified into two groups with five in one group and seven amino acids in the other. Correlation coefficients among the amino acids within each group were high and positive, but the correlation coefficients of amino acids between the two groups were negative. Twenty-five SNP markers associated with multiple amino acids can be used to simultaneously improve multi-amino acid concentration in soybean. Genomic selection analysis of amino acid concentration showed that selection efficiency of amino acids based on the markers significantly associated with all 15 amino acids was higher than that based on random markers or markers only associated with individual amino acid. The identified markers could facilitate selection of soybean varieties with improved seed quality.

19.
Aging (Albany NY) ; 11(24): 12328-12344, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31866582

RESUMO

Methyltransferase-like 1 (METTL1) mediated 7-methylguanosine (m7G) is crucial for the regulation of chemoresistance in cancer treatment. However, the role of METTL1 in regulating chemoresistance of colon cancer (CC) cells to cisplatin is still unclear. This study established the cisplatin-resistant CC (CR-CC) cells and found that METTL1 was low-expressed in CR-CC cells compared to their paired cisplatin-sensitive CC (CS-CC) cells. Besides, overexpressed METTL1 enhanced the cytotoxic effects of cisplatin on CR-CC cells. In addition, miR-149-3p was the downstream target of METTL1, which could be positively regulated by METTL1. Further results validated that miR-149-3p was low-expressed in CR-CC cells comparing to the CS-CC cells. In addition, the promoting effects of overexpressed METTL1 on cisplatin induced CR-CC cell death were abrogated by synergistically knocking down miR-149-3p. Furthermore, S100A4/p53 axis was the downstream target of METTL1 and miR-149-3p, and either overexpressed METTL1 or miR-149-3p increased p53 protein levels in CR-CC cells, which were reversed by upregulating S100A4. Similarly, the promoting effects of overexpressed METTL1 on cisplatin-induced CR-CC cell death were abrogated by overexpressing S100A4. Taken together, overexpression of METTL1 sensitized CR-CC cells to cisplatin by modulating miR-149-3p/S100A4/p53 axis.

20.
BMC Plant Biol ; 19(1): 469, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690290

RESUMO

BACKGROUND: Soybean (Glycine max (L.)) is one the most important oil-yielding cash crops. However, the soybean production has been seriously restricted by salinization. It is therefore crucial to identify salt tolerance-related genes and reveal molecular mechanisms underlying salt tolerance in soybean crops. A better understanding of how plants resist salt stress provides insights in improving existing soybean varieties as well as cultivating novel salt tolerant varieties. In this study, the biological function of GmNHX1, a NHX-like gene, and the molecular basis underlying GmNHX1-mediated salt stress resistance have been revealed. RESULTS: We found that the transcription level of GmNHX1 was up-regulated under salt stress condition in soybean, reaching its peak at 24 h after salt treatment. By employing the virus-induced gene silencing technique (VIGS), we also found that soybean plants became more susceptible to salt stress after silencing GmNHX1 than wild-type and more silenced plants wilted than wild-type under salt treatment. Furthermore, Arabidopsis thaliana expressing GmNHX1 grew taller and generated more rosette leaves under salt stress condition compared to wild-type. Exogenous expression of GmNHX1 resulted in an increase of Na+ transportation to leaves along with a reduction of Na+ absorption in roots, and the consequent maintenance of a high K+/Na+ ratio under salt stress condition. GmNHX1-GFP-transformed onion bulb endothelium cells showed fluorescent pattern in which GFP fluorescence signals enriched in vacuolar membranes. Using the non-invasive micro-test technique (NMT), we found that the Na+ efflux rate of both wild-type and transformed plants after salt treatment were significantly higher than that of before salt treatment. Additionally, the Na+ efflux rate of transformed plants after salt treatment were significantly higher than that of wild-type. Meanwhile, the transcription levels of three osmotic stress-related genes, SKOR, SOS1 and AKT1 were all up-regulated in GmNHX1-expressing plants under salt stress condition. CONCLUSION: Vacuolar membrane-localized GmNHX1 enhances plant salt tolerance through maintaining a high K+/Na+ ratio along with inducing the expression of SKOR, SOS1 and AKT1. Our findings provide molecular insights on the roles of GmNHX1 and similar sodium/hydrogen exchangers in regulating salt tolerance.


Assuntos
Proteínas de Plantas/metabolismo , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Soja/metabolismo , Arabidopsis/genética , Inativação Gênica , Proteínas de Plantas/genética , Potássio/metabolismo , Plantas Tolerantes a Sal/genética , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Soja/genética , Estresse Fisiológico/genética , Regulação para Cima , Vacúolos/metabolismo
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