Schwarzschild-de Sitter Metric and Inertial Beltrami Coordinates

Under consideration of coordinate conditions, we get the Schwarzschild-Beltrami-de Sitter (S-BdS) metric solution of the Einstein field equations with a cosmological constant $\Lambda$. A brief review to the de Sitter invariant special relativity (dS-SR), and de Sitter general relativity (dS-GR, or GR with a $\Lambda$) is presented. The Beltrami metric $B_{\mu\nu}$ provides inertial reference frame for the dS-spacetime. By examining the Schwarzschild-de Sitter (S-dS) metric $g_{\mu\nu}^{(M)}$ existed in literatures since 1918, we find that the existed S-dS metric $g_{\mu\nu}^{(M)}$ describes some mixing effects of gravity and inertial-force, instead of a pure gravity effect arisen from "solar mass" $M$ in dS-GR. In this paper, we solve the vacuum Einstein equation of dS-GR, with the requirement of gravity-free metric $g_{\mu\nu}^{(M)}|_{M\rightarrow 0}=B_{\mu\nu}$. In this way we find S-BdS solution of dS-GR, written in inertial Beltrami coordinates. This is a new form of S-dS metric. Its physical meaning and possible applications are discussed.Comment: 16 pages, 1 figur

Up-regulation of p21 and TNF-α is mediated in lycorine-induced death of HL-60 cells

<p>Abstract</p> <p>Background</p> <p>Leukemia is one of the most life-threatening cancers today, and acute promyelogenous leukemia (APL) is a common type of leukemia. Many natural compounds have already been found to exhibit significant anti-tumor effects. Lycorine, a natural alkaloid extracted from Amaryllidaceae, exhibited anti-leukemia effects in vitro and in vivo. The survival rate of HL-60 cells exposed to lycorine was decreased, cell growth was slowed down, and cell regeneration potential was inhibited. HL-60 cells exhibited typical apoptotic characteristic. Lycorine can suppress leukemia growth and reduce cell survival and inducing apoptosis of tumor cells. The purpose of this work is to elucidate the mechanism by which lycorine induces APL cells.</p> <p>Results</p> <p>When HL-60 cells were treated with different concentration of lycorine, the expression of p21 and TNF-α was up-regulated in a concentration-dependent manner as shown by real-time quantitative reverse transcriptase-polymerase chain reaction and Western blotting. Lycorine also down-regulated p21-related gene expression, including Cdc2, Cyclin B, Cdk2 and Cyclin E, promoted Bid truncation, decreased IκB phosphorylation and blocked NF-κB nuclear import. Cytochrome c was released from mitochondria as observed with confocal laser microscopy.</p> <p>Conclusions</p> <p>The TNF-α signal transduction pathway and p21-mediated cell-cycle inhibition were involved in the apoptosis of HL-60 cells induced by lycorine. These results contribute to the development of new lycorine-based anti-leukemia drugs.</p

Paris polyphylla extract inhibits proliferation and promotes apoptosis in A549 lung cancer cells

Purpose: To investigate the effect of Paris polyphylla extract (PPE) on proliferation and apoptosis in A549 human lung cancer cells.Methods: Morphological changes were examined by microscopy in A549 cells after exposure to PPE. Trypan blue staining of living cells was used to aid the construction of the cell growth curve after treatment with different concentrations of PPE. The influence of PPE on cell proliferation, apoptosis and cell cycle were determined by MTT assay. Protein expressions of key apoptosis-related enzymes were determined by immuno-cytochemical method.Results: PPE inhibited the growth of A549 lung cancer cells at a concentration range of 12.5 – 200.0 μg/mL. Flow cytometry revealed that PPE promoted apoptosis in A549 cells. The proportion of cells in G0/G1-phase increased significantly (p &lt; 0.01), while the proportion of cells in S- and G2/M-phases decreased correspondingly, indicating that the cells were in G0/G1-phase arrest. Cell cycle arrest and apoptosis-inducing effect gradually increased with increase in PPE concentration. With increasing concentration of PPE, there was significant increase in the expressions of caspase-8, caspase-3 and caspase-9, but significant decrease in Ki-67, p21ras protein (p &lt; 0.01).Conclusion: PPE exerts pronounced inhibitory activity on the proliferation of A549 lung cancer cells. It also induces apoptosis in A549 cells, most probably by a mechanism related to Ki-67 and p21 ras protein expression, and arrest of cell cycle in G0/G1-phase.Keywords: Paris polyphylla, Antitumor activity, Lung cancer, A549 cells, p21 ras protein expression, Caspase, Cell cycle arrest, Apoptosi

The expression and significance of P-glycoprotein, lung resistance protein and multidrug resistance-associated protein in gastric cancer

<p>Abstract</p> <p>Background</p> <p>To detect the expression of multidrug resistance molecules P-glycoprotein (P-gp), Lung resistnce protein (LRP) and Multidrug resistance-associated protein (MRP) and analyze the relationship between them and the clinico-pathological features.</p> <p>Methods</p> <p>The expressions of P-gp, LRP and MRP in formalin-fixed paraffin-embedded tissue sections from 59 gastric cancer patients were determined by a labbelled Streptavidin-Peroxidase (SP) immunohistochemical technique, and the results were analyzed in correlation with clinicopathological data. None of these patients received chemotherapy prior to surgery.</p> <p>Results</p> <p>The positive rates of P-gp, LRP, MRP were 86.4%, 84.7% and 27.1%, respectively. The difference between the positive rate of P-gp and MRP was significant statistically, as well as the difference between the expression of MRP and LRP. No significant difference was observed between P-gp and LRP, but the positively correlation between the expression of P-gp and LRP had been found. No significant correlation between the expression of P-gp, LRP, MRP and the grade of differentiation were observed. The expression of P-gp was correlated with clinical stages positively (r = 0.742), but the difference with the expression of P-gp in different stages was not significant.</p> <p>Conclusion</p> <p>The expressions of P-gp, LRP and MRP in patients with gastric cancer without prior chemotherapy are high, indicating that innate drug resistance may exist in gastric cancer.</p

Mitigation of monocyte inflammation by inhibition of sodium phosphate co-transporter with phosphonoformic acid and parthenolide in diabetic nephropathy uremia

Purpose: To investigate the effect of sodium phosphate co-transporter (Pit-1) on the regulation of monocyte inflammation in diabetic nephropathy uremia (DNU) patients and the underlying principles of inflammatory immune response during DNU pathogenesis.Methods: The levels of CD14+ CD16+ and Pit-1 on peripheral blood mononuclear cells (PBMC) were measured by flow cytometry. Serum C-reactive protein (CRP) and 25(OH)D3 were detected by immunoturbidimetry while IL-6 and MCP-1 were assayed with enzyme-linked immunoassay (ELISA). The amounts of vitamin D receptors (VDRs) and Pit-1 mRNA in human acute monocytic leukemia cell lines (THP-1) were determined by quantitative real-time polymerase chain reaction (qRT-PCR), while western blot was utilized for measurement of NF-κB p65 and p-STAT5.Results: Compared to the healthy group, DNU patients showed markedly higher CD14+CD16+, Pit-1, CRP, IL-6 and MCP-1, while 25(OH) D3 was reduced. Following stimulation with PFA or PTN, comparison with DNU group revealed that THP-1 monocytes showed a significant down-regulation of Pit-1 (1.34 ± 0.06 for PFA; 1.60 ± 0.25 for PTN; p &lt; 0.05); NF-κB p65 (2.65 ± 0.25 for PFA; 3.88 ± 0.13 for PTN; p &lt; 0.01), p-STAT5 (2.49 ± 0.10 for PFA; 3.03 ± 0.09 for PTN; p &lt; 0.01) and a significant decrease in levels of IL-6 (55.38 ± 3.22 for PFA, 68.68 ± 6.01 for PTN; p &lt; 0.05); MCP-1( 39.67 ± 3.62 for PFA; 52.62 ± 5.00 for PTN; p &lt; 0.01), except for VDR (0.64 ± 0.15 for PFA, 0.43 ± 0.03 for PTN; p &lt; 0.05) .Conclusion: The level of expression of Pit-1 has a positive correlation with the level of inflammatory monocytes, which indicates that Pit-1 can be used as a new biomarker for DNU diagnosis. In addition, since Pit-1 is connected to NF-κB and STAT5 signaling pathways which are critical to inflammatory immune response, development of drugs that target Pit-1 could be an approach in developing new strategies for DNU therapy.Keywords: Pit-1, Diabetic nephropathy, Uremia, Monocytes, Inflammation, NF-κB, STAT

Symplectic Exact Solution for Stokes Flow in the Thin Film Coating Applications

The symplectic analytical method is introduced to solve the problem of the stokes flow in the thin film coating applications. Based on the variational principle, the Lagrangian function of the stokes flow is established. By using the Legendre transformation, the dual variables of velocities and the Hamiltonian function are derived. Considering velocities and stresses as the basic variables, the equations of stokes flow problems are transformed into Hamiltonian system. The method of separation of variables and expansion of eigenfunctions are developed to solve the governing equations in Hamiltonian system, and the analytical solutions of the stokes flow are obtained. Several numerical simulations are carried out to verify the analytical solutions in the present study and discuss the effects of the driven lids of the square cavity on the dynamic behavior of the flow structure