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Abstract Background The novel gene HA117 is a multidrug resistance (MDR) gene expressed by all-trans retinoic acid-resistant HL-60 cells. In the present study, we compared the multidrug resistance of the HA117 with that of the classical multidrug resistance gene 1 (MDR1) in breast cancer cell line 4T1. Methods Transduction of the breast cancer cell line 4T1 with adenoviral vectors encoding the HA117 gene and the green fluorescence protein gene (GFP) (Ad-GFP-HA117), the MDR1 and GFP (Ad-GFP-MDR1) or GFP (Ad-GFP) was respectively carried out. The transduction efficiency and the multiplicity of infection (MOI) were detected by fluorescence microscope and flow cytometry. The transcription of HA117 gene and MDR1 gene were detected by reverse transcription polymerase chain reaction (RT-PCR). Western blotting analysis was used to detect the expression of P-glycoprotein (P-gp) but the expression of HA117 could not be analyzed as it is a novel gene and its antibody has not yet been synthesized. The drug-excretion activity of HA117 and MDR1 were determined by daunorubicin (DNR) efflux assay. The drug sensitivities of 4T1/HA117 and 4T1/MDR1 to chemotherapeutic agents were detected by Methyl-Thiazolyl-Tetrazolium (MTT) assay. Results The transducted efficiency of Ad-GFP-HA117 and Ad-GFP-MDR1 were 75%-80% when MOI was equal to 50. The transduction of Ad-GFP-HA117 and Ad-GFP-MDR1 could increase the expression of HA117 and MDR1. The drug resistance index to Adriamycin (ADM), vincristine (VCR), paclitaxel (Taxol) and bleomycin (BLM) increased to19.8050, 9.0663, 9.7245, 3.5650 respectively for 4T1/HA117 and 24.2236, 11.0480, 11.3741, 0.9630 respectively for 4T1/MDR1 as compared to the control cells. There were no significant differences in drug sensitivity between 4T1/HA117 and 4T1/MDR1 for the P-gp substrates (ADM, VCR and Taxol) (P < 0.05), while the difference between them for P-gp non-substrate (BLM) was statistically significant (P < 0.05). DNR efflux assay confirmed that the multidrug resistance mechanism of HA117 might not be similar to that of MDR1. Conclusions These results confirm that HA117 is a strong MDR gene in both HL-60 and 4T1 cells. Furthermore, our results indicate that the MDR mechanism of the HA117 gene may not be similar to that of MDR1.

Abstract Objective A novel multi-drug resistance gene named as HA117 has been screened and cloned in multidrug resisitant leukemia cell lines in our previous research, but its function is still unknown. In this study, HA117 gene was investigated whether it could increase the drug resistance in chronic myelogenous myeloid leukemia cell line K562. Methods HA117 was cloned and adenovirus vectors were constructed with the HA117 gene (Adeasy-HA117). K562 cells were infected by Ad-HA117 to get the K562/Ad-HA117 cells with HA117 gene expression. The infection efficiency and the multiplicity of infection (MOI) were detected by fluorescence and flow cytometry. The expression of HA117 gene was detected by RT-PCR. The drug sensitivities of K562/Ad-HA117 cells were detected by Methyl Thiazolyl Tetrazolium (MTT) assay. Results Recombinant adenovirus vectors were constructed and a MOI of 100 is most suitable to infect K562 cells. The infected K562 cells demonstrated in vitro production of HA117 mRNA as measured by reverse-transcriptase polymerase chain reaction. There were no significant changes in K562/Ad-HA117 cells growth, while the drug sensitivities of K562/Ad-HA117 cells to Vincristine, Adriamycin, Etoposide, Daunorubicin, Mitomycin and Cyclophosphamide decreased 4.44, 7.18, 3.01, 9.53, 3.48 and 3.61 times than that of uninfected K562 cells, respectively (P < 0.05). Conclusion Expression of the novel gene HA117 could significantly increased the multi-drug resistance of K562 cells, which indicated that HA117 is a functionally relevant multidrug resistance gene.

This paper is concerned with the following elliptic problem: P(−Δ)mu=u+m∗−1+λu−s1φ1,inB1,u∈D0m,2(B1),(P)where (−Δ)m is the polyharmonic operator, m∗=2NN−2m is the critical Sobolev embedding exponent. B1 is the unit ball in RN, s1 and λ>0 are parameters, φ1>0 is the eigenfunction of (−Δ)m,D0m,2(B1) corresponding to the first eigenvalue λ1 with maxy∈B1φ1(y)=1, u+=max(u,0). By using the Lyapunov–Schimit reduction method combining with the minimax argument, we construct the solutions to (P) with many peaks near the boundary but not on the boundary of the domain. Moreover, we prove that the number of solutions for the problem (P) is unbounded as the parameter tends to infinity, therefore proving the Lazer–McKenna conjecture for the higher order case with critical growth. [ABSTRACT FROM AUTHOR]

A novel mycovirus, named "Corynespora cassiicola bipartite mycovirus 1" (CcBV1), was isolated from a phytopathogenic fungus, Corynespora cassiicola, the causal agent of rubber leaf fall disease. The nucleotide sequence of the complete genome of CcBV1, which consists of two double-stranded RNA (dsRNA) segments, was determined. The first dsRNA is 2,002 bp in length and contains a single open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) (69 kDa), while the second is 1,738 bp in length and contains a single ORF encoding a hypothetical protein of unknown function, with an approximately molecular weight of 36 kDa. The amino acid sequences of the both deduced proteins are most similar (58.9% and 45.1% identity, respectively) to those of Cryphonectria parasitica bipartite mycovirus 1 (CpBV1). Phylogenetic analysis indicated that CcBV1 clusters together with CpBV1 and other unassigned dsRNA mycoviruses. To the best of our knowledge, this represents the first report of a mycovirus infecting C. cassiicola. [ABSTRACT FROM AUTHOR]

In this paper, we consider the following critical quasilinear equation with Hardy potential:{−∑Ni,j = 1 Dj(aij(u)Diu) + 1/2∑Ni,j = 1a′ij(u)DiuDju + a(x)u = ν|u|q−2u + μu/|x|2 + |u|2∗−2u,in RN, u(x) → 0 as |x| → ∞, where aij(u)∈C1(R,R), ν > 0, 0 ≤ μ < αμ, and max{αμγ/αμ−μ + 2,2∗ − 2/N−2 √μ − μ/α} (1) < q < 2∗, α,γ >0, μ = (N−2)2/4, 2∗ = 2N/N−2 is the Sobolev critical exponent. And a(x)a(x) is a finite, positive potential function satisfying suitable decay assumptions. By using truncation method combining with the regularization approximation approach and compactness arguments, we prove the existence of infinitely many solutions for this equation. [ABSTRACT FROM AUTHOR]

In this paper, we consider the following quasilinear elliptic equation with critical growth and a Hardy term: (P) − ∑ i , j = 1 N D j (c i j (w) D i w) + 1 2 ∑ i , j = 1 N c i j ′ (w) D i w D j w − μ | w | 2 (s − 1) w | x | 2 = a | w | 2 (s − 1) w + | w | 2 ∗ s − 2 w , i n Ω , w = 0 , on  ∂ Ω , where s ≥ 1 , a is a constant, μ ≥ 0 , 2 ∗ = 2 N N − 2 is the Sobolev critical exponent. And Ω ⊂ ℝ N is an open bounded domain which contains the origin. We will study the existence of infinitely many solutions for (P). To achieve this goal, we first perform various kinds of change of variables to overcome the difficulties caused by the unboundedness of c i j (t) (| c i j (t) | ∼ | t | 2 s − 2 for large | t |) and the lack of a global monotone condition (G) (see below) on c i j (t) , then combining the idea of regularization approach and subcritical approximation we prove the existence of infinitely many solutions for (P). Our results show that under some suitable assumptions on c i j ′ (w) , without the perturbation of the lower term a | w | 2 (s − 1) w , we can still obtain the existence of infinitely many solutions for (P). [ABSTRACT FROM AUTHOR]

The study is focused on the physical and chemical characterization of Chinese willow leaf ash (WLA) produced by calcination at 500, 700, and 850°C and on WLA residue leaching to the aqueous solution. The grain size distribution, chemical composition, and microstructure of WLA were investigated by laser granulometric distribution, X-ray fluorescence (XRF), and scanning electron microscopy (SEM), respectively. The ash samples obtained before and after dissolution were analyzed using X-ray powder diffraction (XRD) to identify the minerals. The X-ray photoelectron spectroscopy (XPS) of WLA was used to illustrate the Si2p and Al2p transformations. The zeta potential, electrical conductivity and pH values of a WLA mixing solution were tested as a function of dissolution time. Si and K were the dominant constituents of the WLA. The electrical conductivity value was nearly stable at longer dissolution times. The zeta potential of WLA was negative. Calcite, sylvite, and synthetic corundum were detected in the WLA samples prepared at 500ºC, quartz, calcite and sylvite were easily identified in the WLA samples prepared at 700ºC, and wollastonite, lime, and anhydrite were detected in WLA prepared at 850°C. The peak of Si2p intensity line shifted to a lower position due to the higher levels of Si-O-X synthesized at elevated calcination temperature. These conclusions could help to identify a possible use of WLA in the cementing systems. [ABSTRACT FROM AUTHOR]

In this paper, we will study the local uniqueness of single bubbling solutions for elliptic problems of Ambrosetti–Prodi type with critical growth in a unit ball. As a result, we are able to count the exact number of single bubbling solutions for these type of elliptic problems. [ABSTRACT FROM AUTHOR]

Background: Geographical variation in morphological traits may reflect evolutionary patterns of morphological adaptability along environmental gradients. Comprehensive information on longitudinal patterns of morphological trait variation is very meaningful to explore morphological diversity and evolutionary trends in widespread bermudagrass. Methods: To explore the spatial patterns of morphological traits, we investigated 10 morphological traits of bermudagrass and 10 soil nutrient indexes and collected local climate data for 13 different regions from 119°E to 105°E along the latitude 34°N. Results: Considerable variations in morphological traits were observed at different longitudes, and the variations in most of the evaluated traits within populations were lower than those among populations. All of the 13 different longitudinal sites were divided into three groups based on morphological traits by cluster analysis. The major sources of diversity at the different longitudes were leaf length of the erect shoot, leaf width of the erect shoot, and the internode lengths of the erect shoot and stolon as determined by principal component analysis. Pearson correlation analysis also indicated that longitude was significantly and negatively correlated with these traits as well. Mean average rainfall was significantly correlated with leaf length of the erect shoot and the internode lengths of the erect shoot and stolon, while mean average temperature was only significantly correlated with internode length of the erect shoots. Available sulfur was significantly correlated with internode length of the erect shoot, plant height, and reproductive branch height, while the exchangeable Ca was significantly correlated with internode lengths of the erect shoot and stolon. Soil pH was significantly correlated with the internode length of the stolon. Longitude is an important factor that affects morphological trait variation in wild bermudagrass, and the leaves of the erect shoot and the internode length enlarged significantly with the collection sites moving from east to west. Conclusion: Different combinations and interactions of environmental factors (soil and climate) along a longitudinal gradient may have strong effects on one or more morphological traits of bermudagrass. [ABSTRACT FROM AUTHOR]

This paper is concerned with the existence and asymptotical behavior of positive ground state solutions for a class of critical quasilinear Schrödinger equation. By using a change of variables and variational argument, we prove the existence of positive ground state solution and discuss their asymptotical behavior. [ABSTRACT FROM AUTHOR]

This paper is concerned with the following nonlinear Schrödinger systems:⎧⎪ ⎪ ⎪⎨⎪ ⎪ ⎪⎩−Δu+a(x)u=|u|p−2u+β|u|p2−2u|v|p2 in RN−Δv+a(x)v=|v|p−2v+β|v|p2−2v|u|p2 in RN(u,v)∈(H1(RN))2, (P)where N≥3 and 2

Knowledge of ploidy level and genome size in a germplasm collection is critical before studying genetic diversification of different environmental range in grasses and other plants. We assessed the geographic patterns in ploidy level and genome size of 216 individuals of Cynodon dactylon (L.) Pers. (common bermudagrass) by flow cytometry of accessions sampled from 16 geographic sites along a latitudinal gradient from 22°35′ N to 36°18′ N across China. Flow cytometry histograms combined with mitotic chromosome observations results show that tetraploids were the most frequent ploidy level, constituting 44.91% of all individuals. Nuclear DNA contents were 2.384, 2.419, 2.437, 2.873 and 3.288 pg/2C for the diploid, triploid, tetraploid, pentaploid and hexaploid, respectively. Higher proportions of polyploid individuals were observed within populations at the highest and lowest latitudes. In addition, monoploid genome size of C. dactylon progressively increased with increasing ploidy level. Temperature and precipitation had the influence on ploidy level for all the sites. The relationship between ploidy level and geographic distribution for C. dactylon will facilitate the utilization of this species for biological and genetic research. [ABSTRACT FROM AUTHOR]

Coal gasification slag (CGS) has pozzolanic activity, and it could be used as a supplementary cementitious material after be activated by some solid waste, which will promote resource utilization of solid waste. In this paper, coal calcium carbide slag and desulfurization gypsum were chosen to activate CGS, the excitation effects were evaluated in different ways and compared with those of salt activators. The microscopic were measured by thermal gravimetry (TG), scanning electron microscopy (SEM) and X-ray diffractometer (XRD) to analyze the excitation mechanism of CGS. The results show that the excitation effects of calcium carbide slag and desulfurization gypsum on CGS are superior to those of salt activators; Through microscopic analysis, the activator promotes the dissolution of glassy state in CGS, accelerates the disaggregation of network structures such as silicon and oxygen, enhancing the activity of CGS. The results of this study can provide references for the excitation of CGS. [Display omitted] • The method of "solid waste excited coal gasification slag" was first adopted. • Multi-dimensional descriptions of the potential of solid waste as activators. • Differences in the excitation of solid waste and salt activators are explained. • Revealed the excitation mechanism of activator on coal gasification slag. [ABSTRACT FROM AUTHOR]