Conversion of the normal protease-sensitive prion protein (PrP) to its abnormal protease-resistant isoform (PrP-res) is a major feature of the pathogenesis associated with transmissible spongiform encephalopathy (TSE) diseases. In previous experiments, PrP conversion was inhibited by a peptide composed of hamster PrP residues 109 to 141, suggesting that this region of the PrP molecule plays a c...

the clinical use of prp therapy in the practical setting of orthopaedic fields is increasing partly because of the accessibility of devices that are used in outpatient preparation and delivery. another reason is the strong advertisement of prp procedures as the ultimate treatment and novel technology for knee problems by a few orthopaedic surgeons based on claims of abundant scientific evidence...

Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp (-/-)) mice. So far, six types of Prnp (-/-) mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obta...

Conversion of cellular prion protein (PrP(C)) into a pathological conformer (PrP(Sc)) is thought to be promoted by PrP(Sc) in a poorly understood process. Here, we report that in wild-type mice, the expression of PrP(C) rendered soluble and dimeric by fusion to immunoglobulin Fcgamma (PrP-Fc(2)) delays PrP(Sc) accumulation, agent replication, and onset of disease following inoculation with infe...

Conformational conversion of the normal cellular isoform of prion protein, PrP(C), a glycoprotein anchored to the cell membrane by a glycosylphosphatidylinositol moiety, into the abnormally folded, amyloidogenic prion protein, PrP(Sc), plays a pivotal role in the pathogenesis of prion diseases. It has been suggested that PrP(C) might be functionally disturbed by constitutive conversion to PrP(S...

In prion diseases, the cellular form of the prion protein, PrP(C), undergoes a conformational conversion to the infectious isoform, PrP(Sc). PrP(C) associates with lipid rafts through its glycosyl-phosphatidylinositol (GPI) anchor and a region in its N-terminal domain which also binds to heparan sulfate proteoglycans (HSPGs). We show that heparin displaces PrP(C) from rafts and promotes its end...

Studies in transgenic mice revealed that neurodegeneration induced by scrapie prion (PrP(Sc)) propagation is dependent on neuronal expression of the cellular prion protein PrP(C). On the other hand, there is evidence that PrP(C) itself has a stress-protective activity. Here, we show that the toxic activity of PrP(Sc) and the protective activity of PrP(C) are interconnected. With a novel co-cult...

The principal infectious and pathogenic agent in all prion disorders is a beta-sheet-rich isoform of the cellular prion protein (PrP(C)) termed PrP-scrapie (PrP(Sc)). Once initiated, PrP(Sc) is self-replicating and toxic to neuronal cells, but the underlying mechanisms remain unclear. In this report, we demonstrate that PrP(C) binds iron and transforms to a PrP(Sc)-like form (*PrP(Sc)) when hum...

BACKGROUND The optimal platelet-rich plasma (PRP) for treatment of supraspinatus tendinopathy has not been determined. PURPOSE To evaluate the effect of low- versus high-leukocyte concentrated PRP products on catabolic and anabolic mediators of matrix metabolism in diseased rotator cuff tendons. STUDY DESIGN Controlled laboratory study. METHODS Diseased supraspinatus tendons were treated ...