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Rheumatoid arthritis (RA) is a chronic, autoimmune and inflammatory joint disease with a poorly understood etiology. Despite widespread diagnostic use of anti-citrullinated protein antibodies and rheumatoid factor proteins there is a strong demand for novel serological biomarkers to improve the diagnosis this disease. The present study was aimed to identify novel autoantigens involved in rheumatoid arthritis (RA) pathogenesis through immune-proteomic strategy. Synovial fluid samples from clinically diagnosed RA patients were separated on two-dimensional gel electrophoresis (2-DE). Samples from patients with non-RA rheumatisms (osteoarthritis and trauma) were used as controls. Immunoreactive proteins were spotted by Western blotting followed by identification through Q-TOF mass spectrometer analysis. Forty Western blots were generated using plasma from ten individual RA patients and 33 reactive spots were identified, 20 from the high molecular weight (HMW) gel and 13 from the low molecular weight (LMW) gel. Among the 33 common immunogenic spots, 18 distinct autoantigens were identified, out of which 14 are novel proteins in this context. Expression analysis of five important proteins, vimentin, gelsolin, alpha 2 HS glycoprotein (AHSG), glial fibrillary acidic protein (GFAP), and α1B-glycoprotein (A1BG) by Western blot analysis using their specific antibodies revealed their higher expression in RA synovial fluid as compared to non-RA samples. Recombinantly expressed GFAP and A1BG protein were used to develop an in-house ELISA to quantify the amount of autoantibodies in the RA patients. RA patients revealed an increase in the expression of GFAP and A1BG in the plasma as compared to osteoarthritis patients. Therefore, GFAP and A1BG can be proposed as potential new autoantigens of diagnostic importance for RA subjects. Further characterization of these proteins in rheumatoid arthritis will be helpful in understanding the role of these proteins in the disease pathogenesis providing new diagnostic tool with better specificity and accurate detection of the disease.

We have calculated the ground-state eigenvalues of the kx4 anharmonic oscillator nonperturbatirely, using the Hill determinant. Our results a r e in remarkable agreement with those obtained from the or el-pad6 approximants of the perturbation series.From an exhaustive numerical analysis of the integral exists for that z . To facilitate numerical perturbation series for the ground-state energy computation, Graffi et al. used Pad6 approximants level of the one-dimensional anharmonic oscillator for +(tz). for which the Hamiltonian i s given byIn this note, we wish to point out that exact values of the energy levels of the anharmonic oscillator d2can also be obtained without recourse to the stan-dard perturbation series and associated summability techniques. Our approach, essentially based Bender and Wu' have shown that the power series in h is divergent for all h though each term of the series is finite. Further, they show that the energy levels of the system orginally defined for real h > 0 can be analytically continued into the complex h plane and that the continuation has an infinite number of branch points with a limit point at h = 0. Such series a r e quite common in relativistic quantum mechanics and the usual belief i s that they a r e asymptotic in nature.' It i s well known in the mathematical literature3 that such series can often be summed4 uniquely through the use of such summability techniques a s the Stieltjes-Pad6 o r the Borel methods. Simon5 has recently investigated the anharmonic oscillator with the general anharmonic term AX'" ( m an integer > 0) and has shown that the pth energy level E:(h) i s analytic in a certain r egion of the X plane and that the perturbation series i s asymptotic to the value EF(h). In particular, he has calculated E;(A) by converting the perturbation series into a series of pad6 approximants for various values of A. In a recent communication, Graffi et uLs6 have shown how improved values of the ground-state energy level for arbitrary h can be obtained by using Pad6 approximants of the Borel transform of the asymptotic perturbation series. In essence, their method consists in r eplacing the s e r i e s C:=, anzn by the Borel sumWithin their regions of convergence both series a r e identical, but for values of z for which the series C ; = , u,zn diverges, the integral representation gives the value of the series provided the upon solving the Hill determinants in finding eigenvalues, has long been known in the literature of mathematical physics .7 From our analysis we find the following: (i) For small h (A <

The ground state as well as excited energy levels of the generalized anharmonic oscillator defined by the Hamiltonian Hm = − d2/dx2+x2+ λx2m, m = 2,3, …, have been calculated nonperturbatively using the Hill determinants. For the λx4 oscillator, the ground state eigenvalues, for various values of λ, have been compared with the Borel-Padé sum of the asymptotic perturbation series for the problem. The agreement is excellent. In addition, we present results for some excited states for m = 2 as well as the ground and the first even excited states for m = 3 and 4. The behaviour of all the energy levels with respect to the coupling parameter shows a qualitative similarity to the ground state of the λx4 oscillator. Thus the results are model independent, as is to be expected from the WKB approximation. Our results also satisfy the scaling property that εn(m)(λ)/λ1/(m+1) tend to a finite limit for large λ, and always lie within the variational bounds, where available.

Partial creation in de Sitter spacetime is studied in a complex-time WKB approximation. It is found that the particle production parallels the description of particle creation by a collapsing spherical body. The appropriate vacuum for an inflationary early universe is the Hartle--Hawking vacuum; this is also a general feature of expanding spacetimes. The effect of particle production back on the metric is treated in a way that differs from the standard semiclassical approach.