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Stimulator of interferon genes (STING) is a transmembrane protein in endoplasmic reticulum and plays crucial roles in autophagy, antiviral and anti-tumor responses. However, there are few studies on the transcriptional regulation mechanism of STING.The 5' RACE experiment was used to determine the location of STING promoters. Luciferase reporting assay confirmed the activity and core region of STING internal promoter. Site-directed mutagenesis confirmed that NF-κB regulates the activity of STING promoters. The regulation of NF-κB on STING was investigated by real-time quantitative PCR, western blot, chromatin immunoprecipitation assay and lipopolysaccharide (LPS) inflammatory cell model.There was also a transcription start site at the 17 bp sequence upstream of STING second exon. STING-285 was the core region of the internal promoter. After NF-κB binding site mutation, the activity of STING internal promoter decreased significantly. In addition, we found that NF-κB can bind to the promoter region of wild-type STING. Overexpression of NF-κB significantly increased the activity of STING internal promoter and wild-type promoter, while knockdown of endogenous NF-κB significantly inhibited the activity of STING promoters. The binding of NF-κB to STING promoters in vivo were confirmed by chromatin immunoprecipitation assay. Meanwhile, we stimulated HeLa cells with LPS to activate the NF-κB pathway and found that STING expression was up-regulated.These results suggest that transcription factor NF-κB positively regulated the expression of STING via alternative promoter usage. This provides a new basis and potential drug targets for the clinical treatment of STING related diseases.

Hepatitis delta virus (HDV) is a defective single negative chain RNA virus, as its envelope protein synthesis is dependent on hepatitis B virus (HBV). Studies have consistently shown that coinfection of HBV and HDV is the most serious form of viral hepatitis, with accelerated progression to liver cirrhosis and hepatocellular carcinoma. About 74 million of HBV surface antigen (HBsAg) positive patients worldwide are also co-infected with HDV. Besides, patients with intravenous drug use and high-risk sexual behavior are at higher risk of HDV infection. Therapeutic schedules for HDV are limited, and relapse of HDV has been observed after treatment with pegylated interferon alpha. To reduce the transmission of HDV, all people infected with HBV should be screened for HDV. At present, several serological and molecular detection methods are widely used in the diagnosis of HDV. However, due to the lack of international standards diagnostic results from different laboratories are often not comparable. Therefore, the true prevalence of HDV is still unclear. In this manuscript, we have analyzed various factors influencing the estimation of HDV prevalence. We have also discussed about the advantages and disadvantages of currently available HDV laboratory diagnostic methods, in order to provide some ideas for improving the detection of HDV.

The structure of liquid Ga at ambient pressure (AP) were generated separately via ab initio and classical molecular dynamics simulations, and analysed with a cluster approach developed in terms of the local bond-orientational order (LBOO) parameters. Two types of cluster structures were found in both simulated liquids, one typified by sixfold orientational symmetry and the other showing fourfold orientational symmetry: The static structure factors (SSF) of the former are akin to that of the hard-sphere (HS) fluid; however, the SSFs of the latter display either an asymmetric first peak with a shape different from that of the HS fluid or even a shoulder on the high-q side of the first peak, similar as the anomalous SSF of liquid Ga at AP.

In terms of the local bond-orientational order (LBOO) parameters, a cluster approach to analyze local structures of simple liquids was developed. In this approach, a cluster is defined as a combination of neighboring seeds having at least nb local-orientational bonds and their nearest neighbors, and a cluster ensemble is a collection of clusters with a specified nb and number of seeds ns. This cluster analysis was applied to investigate the microscopic structures of liquid Ga at ambient pressure (AP). The liquid structures studied were generated through ab initio molecular dynamics simulations. By scrutinizing the static structure factors (SSFs) of cluster ensembles with different combinations of nb and ns, we found that liquid Ga at AP contained two types of cluster structures, one characterized by sixfold orientational symmetry and the other showing fourfold orientational symmetry. The SSFs of cluster structures with sixfold orientational symmetry were akin to the SSF of a hard-sphere fluid. On the contrary, the SSFs of cluster structures showing fourfold orientational symmetry behaved similarly as the anomalous SSF of liquid Ga at AP, which is well known for exhibiting a high-q shoulder. The local structures of a highly LBOO cluster whose SSF displayed a high-q shoulder were found to be more similar to the structure of β-Ga than those of other solid phases of Ga. More generally, the cluster structures showing fourfold orientational symmetry have an inclination to resemble more to β-Ga.

A solution to a given equation is structurally stable if it suffers only an infinitesimal change when the equation (not the solution) is perturbed infinitesimally. We have found that structural stability can be used as a velocity selection principle for propagating fronts. We give examples, using numerical and renormalization group methods., 14 pages, uiucmac.tex, no figures

We consider the propagation of a plane front separating a turbulent region of fluid from a quiescent region. Initially, the turbulent-energy distribution as a function of z, the displacement normal to the front, is assumed to be localized, and after a time t, general renormalization-group arguments show that there is a similarity solution of the form q(z,t)\ensuremath{\sim}${\mathit{t}}^{\mathrm{\ensuremath{-}}(2/3+2\mathrm{\ensuremath{\alpha}}\mathrm{\ifmmode \tilde{}\else \~{}\fi{}})}$f (${\mathit{zt}}^{\mathrm{\ensuremath{-}}(2/3+\mathrm{\ensuremath{\beta}})}$, \ensuremath{\epsilon}), where \ensuremath{\alpha}\ifmmode \tilde{}\else \~{}\fi{} and \ensuremath{\beta} are \ensuremath{\epsilon}-dependent anomalous dimensions, satisfying the scaling law \ensuremath{\alpha}\ifmmode \tilde{}\else \~{}\fi{}+\ensuremath{\beta}=0 and \ensuremath{\epsilon} is a measure of the dissipation. Using perturbation theory, we calculate values of \ensuremath{\alpha}\ifmmode \tilde{}\else \~{}\fi{} and \ensuremath{\beta} to O(\ensuremath{\epsilon}), which are in good agreement with numerical calculations, and we explicitly verify the above scaling law and find the form of the scaling function f.

Granulosa cell tumors are serious ovarian neoplasms that can occur in women of all ages. While there have been numerous attempts to understand the cause of these malignancies, the pathogenesis of granulosa cell tumors (GCTs) still remains largely unknown. G-protein coupled receptor kinases (GRKs) are important regulators of signal transduction through the process of receptor desensitization and internalization. Receptors that are regulated by GRKs are members of the large family of seven-transmembrane receptors and include the follicle stimulating hormone receptor (FSHR). In granulosa cells, the FSH signaling system is responsible for cell proliferation, differentiation, and steroidogenesis. In the studies presented, we examined GRK mRNA and protein expression in nonmalignant human granulosa cells, in KGN cells, a human GCT cell line, and in a panel of human GCT samples. The KGN tumor cells express significantly less GRK4 alpha/beta protein and higher levels of GRK2 and GRK4 gamma/delta protein as compared to nonmalignant human granulosa cells. In human GCT samples, GRK4 alpha/beta protein was detected in 3 of the 13 tumor samples, whereas gamma/delta proteins expression was detected in all samples. These findings suggest that GRK protein expression is altered in GCTs and may be involved in the pathogenesis of these tumors.

Perturbative renormalization group theory is developed as a unified tool for global asymptotic analysis. With numerous examples, we illustrate its application to ordinary differential equation problems involving multiple scales, boundary layers with technically difficult asymptotic matching, and WKB analysis. In contrast to conventional methods, the renormalization group approach requires neither {\it ad hoc\/} assumptions about the structure of perturbation series nor the use of asymptotic matching. Our renormalization group approach provides approximate solutions which are practically superior to those obtained conventionally, although the latter can be reproduced, if desired, by appropriate expansion of the renormalization group approximant. We show that the renormalization group equation may be interpreted as an amplitude equation, and from this point of view develop reductive perturbation theory for partial differential equations describing spatially-extended systems near bifurcation points, deriving both amplitude equations and the center manifold., Comment: 44 pages, 2 Postscript figures, macro \uiucmac.tex available at macro archives or at ftp://gijoe.mrl.uiuc.edu/pub

We present a numerical implementation of the renormalization group (RG) for partial differential equations, constructing similarity solutions and travelling waves. We show that for a large class of well-localized initial conditions, successive iterations of an appropriately defined discrete RG transformation in space and time will drive the system towards a fixed point. This corresponds to a scale-invariant solution, such as a similarity or travelling-wave solution, which governs the long-time asymptotic behavior. We demonstrate that the numerical RG method is computationally very efficient., 14 pages, Postscript file of paper and 3 figures distributed as self-unpacking uuencoded compressed tar file.Also available by anonymous ftp to gijoe.mrl.uiuc.edu (128.174.119.153), file /pub/numrg.uu

We study the propagation of uniformly translating fronts into a linearly unstable state, both analytically and numerically. We introduce a perturbative renormalization group (RG) approach to compute the change in the propagation speed when the fronts are perturbed by structural modification of their governing equations. This approach is successful when the fronts are structurally stable, and allows us to select uniquely the (numerical) experimentally observable propagation speed. For convenience and completeness, the structural stability argument is also briefly described. We point out that the solvability condition widely used in studying dynamics of nonequilibrium systems is equivalent to the assumption of physical renormalizability. We also implement a variational principle, due to Hadeler and Rothe, which provides a very good upper bound and, in some cases, even exact results on the propagation speeds, and which identifies the transition from ` linear'- to ` nonlinear-marginal-stability' as parameters in the governing equation are varied., Comment: 34 pages, plain tex with uiucmac.tex. Also available by anonymous ftp to gijoe.mrl.uiuc.edu (128.174.119.153), file /pub/front_RG.tex (or .ps.Z)

We illustrate how to extend the concept of structural stability through applying it to the front propagation speed selection problem. This consideration leads us to a renormalization group study of the problem. The study illustrates two very general conclusions: (1) singular perturbations in applied mathematics are best understood as renormalized perturbation methods, and (2) amplitude equations are renormalization group equations., Comment: 38 pages, LaTeX, two PostScript figures available by anonymous ftp to gijoe.mrl.uiuc.edu (128.174.119.153) files /pub/front_kkfest_fig*

We analyze the long-time behavior of the modified porous-medium equation ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$u=D\ensuremath{\Delta}${\mathit{u}}^{1+\mathit{n}}$ in d dimensions, where n is arbitrary and D=1 for ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$ug0 and D=1+\ensuremath{\epsilon} for ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$u0. This equation describes inter alia the height of a groundwater mound during gravity-driven flow in porous media (d=2, n=1) and the propagation of strong thermal waves following an intense explosion (d=3, n=5). Using general renormalization-group (RG) arguments, we show that a radially symmetric mound exists of the form u(r,t)\ensuremath{\sim}${\mathit{t}}^{\mathrm{\ensuremath{-}}(\mathit{d}\mathrm{\ensuremath{\theta}}+\mathrm{\ensuremath{\alpha}})}$f(${\mathit{rt}}^{\mathrm{\ensuremath{-}}(\mathrm{\ensuremath{\theta}}+\mathrm{\ensuremath{\beta}})}$, \ensuremath{\epsilon}), where \ensuremath{\theta}==1/(2+nd) and \ensuremath{\alpha} and \ensuremath{\beta} are \ensuremath{\epsilon}-dependent anomalous dimensions, obeying the scaling law n\ensuremath{\theta}\ensuremath{\alpha}+(1-nd\ensuremath{\theta})\ensuremath{\beta}=0. We calculate \ensuremath{\alpha} and \ensuremath{\beta} to O(\ensuremath{\epsilon}), for general d and n, using a perturbative RG scheme. In the case of groundwater spreading, our results to O(${\mathrm{\ensuremath{\epsilon}}}^{2}$) are in good agreement with numerical calculations, with a relative error in the anomalous dimension \ensuremath{\alpha} of about 3% when \ensuremath{\epsilon} is 0.5.

We show with several examples that renormalization group (RG) theory can be used to understand singular and reductive perturbation methods in a unified fashion. Amplitude equations describing slow motion dynamics in nonequilibrium phenomena are RG equations. The renormalized perturbation approach may be simpler to use than other approaches, because it does not require the use of asymptotic matching, and yields practically superior approximations., Comment: 13 pages, plain tex + uiucmac.tex (available from babbage.sissa.it), one PostScript figure appended at end. Or (easier) get compressed postscript file by anon ftp from gijoe.mrl.uiuc.edu (128.174.119.153), file /pub/rg_sing_prl.ps.Z