Comparative Study on the Therapeutic Potential of Neurally Differentiated Stem Cells in a Mouse Model of Multiple Sclerosis

Background: Transplantation of neural stem cells (NSCs) is a promising novel approach to the treatment of neuroinflammatory diseases such as multiple sclerosis (MS). NSCs can be derived from primary central nervous system (CNS) tissue or obtained by neural differentiation of embryonic stem (ES) cells, the latter having the advantage of readily providing an unlimited number of cells for therapeutic purposes. Using a mouse model of MS, we evaluated the therapeutic potential of NSCs derived from ES cells by two different neural differentiation protocols that utilized adherent culture conditions and compared their effect to primary NSCs derived from the subventricular zone (SVZ). Methodology/Principal Findings: The proliferation and secretion of pro-inflammatory cytokines by antigen-stimulated splenocytes was reduced in the presence of SVZ-NSCs, while ES cell-derived NSCs exerted differential immunosuppressive effects. Surprisingly, intravenously injected NSCs displayed no significant therapeutic impact on clinical and pathological disease outcomes in mice with experimental autoimmune encephalomyelitis (EAE) induced by recombinant myelin oligodendrocyte glycoprotein, independent of the cell source. Studies tracking the biodistribution of transplanted ES cellderived NSCs revealed that these cells were unable to traffic to the CNS or peripheral lymphoid tissues, consistent with the lack of cell surface homing molecules. Attenuation of peripheral immune responses could only be achieved through multiple high doses of NSCs administered intraperitoneally, which led to some neuroprotective effects within the CNS

Multibit Continuous Time Σ∆ Modulators with a Reduced

Abstract: A drawback of continuous time Σ∆-modulators is their sensitivity to clock jitter. An appropriate way to counteract this is to use a multi bit feedback loop. This requires a high resolution multi bit quantizer. However, every extra bit in the quantizer doubles its complexity and power consumption. In this paper, a new Σ∆-modulator architecture is proposed. The implementation issues are discussed and the modulators ’ performance was compared with a conventional modulator through computer simulations. In the simulation examples the modulator had a quantizer with a quantization step corresponding to 6bit accuracy. Compared to the conventional modulator, the proposed architectures achieves the same performance while the required number of comparators in the high resolution quantizer can be reduced significantly

IgG4-related disease of the hepatobiliary tract : 2 case reports and review of the literature

IgG4-related disease is a rare inflammatory disorder that may mimic many infectious, malignant, and autoimmune conditions. The biliary tract is frequently involved, but hepatic lesions are rarely seen. Diagnosis is often delayed due to the absence of specific clinical and radiological signs, and the lack of an accurate diagnostic marker. Differential diagnosis includes cholangiocarcinoma, primary sclerosing cholangitis and intrinsic or metastatic liver disease. Corticosteroids are the cornerstone of therapy but treatment has not been standardized and relapse is common. Based on two cases of IgG4-related hepatobiliary disease, we review the current literature on this pathological entity

Prostate-specific antigen immunosensing based on mixed self-assembled monolayers, camel antibodies and colloidal gold enhanced sandwich assays

Prostate-specific antigen (PSA) is a valuable biomarker for prostate cancer screening. We developed a PSA immunoassay on a commercially available surface plasmon resonance biosensor. Our PSA receptor molecule consists of a single domain antigen-binding fragment, cAbPSA-N7, derived from dromedary heavy-chain antibodies and identified after phage display. It binds PSA with a high k(on) value of 1.9 x 10(6) M-1 s(-1), and was covalently immobilised on a gold substrate via a mixed self-assembled monolayer (SAM) of alkanethiols by using carbodiimide-coupling chemistry in 10 mM acetate buffer pH 5.5 to obtain an optimal pre-concentration. The best performing and optimised mixed SAM consisted of (10%) 16-mercapto-1-hexadecanoic acid (16-MHA) for covalent cAbPSA-N7 immobilisation and (90%) 11-mercapto-l-undecanol (11-MUOH) to minimise non-specific adsorption of the analyte. In this way, two advantages are incorporated in a single coupling layer. Up to 28 fmol/mm(2) of cAbPSA-N7 could be immobilised and 30% of its binding sites participate actively in PSA interaction. In addition, the optimised layer showed also optimal performance to assess physiological samples. Although PSA concentrations as low as 10 ng/ml could be detected directly, this detection limit could be enhanced to PSA levels in the sub ng/ml range by introducing a sandwich assay involving a biotinylated secondary antibody and streptavidin modified gold nanoparticles. This approach realises the PSA detection at clinical relevant concentrations. (c) 2004 Elsevier B.V. All rights reserved