BACKGROUND The hedgehog (Hh) signaling pathway is aberrantly activated in many human carcinomas including pancreatic cancer and regulates tumor cell growth. Overproduction of sonic hedgehog (Shh), a ligand of the Hh signaling pathway, increases the Hh signaling activity through transmitting the signal to patched-1 (Ptch1), the receptor of the Hh signaling pathway. MATERIALS AND METHODS a-Ptch...

The unicellular Tetrahymena pyriformis contains digoxin-like materials (digoxin, digitoxin, digoxigenin). The effect of two aminoacid-type hormones (histamine and serotonin) and a peptide hormone (insulin) was studied on the level of the hormone-like steroid, digoxin, in the concentrations of 10 and 10 by using immunocytochemistry and flow cytometric and confocal microscopic analysis. Each horm...

Physiological digestion and absorption of nutrients within the gastrointestinal tract requires a complex interaction between motor, secretory, digestive, and absorptive functions that is vulnerable to a multitude of potential disturbances which may lead to global or specific malabsorption syndromes. Potential pathomechanisms that are illustrated in this article include insufficient mechanical b...

Typically, structure calculations of helical membrane proteins have been designed to take advantage of the structural autonomy of secondary structure elements, as postulated by the two-stage model of Engelman and Popot. The assumption used in these procedures is that transmembrane helices can be reliably restrained into canonical formations. We analyze this assumption for two membrane proteins ...

Helminthosporoside is the host-specific toxin produced by Helminthosporium sacchari, the organism causing eyespot disease on sugarcane. Clones of sugarcane susceptible to the toxin posses a membrane protein that binds the toxin. Membranes of resistant clones do not bind the toxin. In this study, a binding protein from a susceptible clone was compared with its counterpart from a resistant clone....

The possible existence in the rat spinal cord of a peptide related to VIP, VIP(22-28), has been evaluated. VIP contains paired basic aminoacid residues at which posttranslational cleavage of these peptides might occur. The lumbo-sacral region of rat spinal cord had the most VIP(22-28)-like immunoreactivity (ir-VIP(22-28]. Chromatographic analysis of spinal extracts showed that ir-VIP(22-28) con...

Staphylococcal leucotoxins result from the association of class S components and class F component inducing the activation and the permeabilization of the target cells. Like alpha-toxin, the leucotoxins are pore-forming toxins with more than 70% beta-sheet. This was confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. In addition, threonine 28 of a predi...

50S-derived cores were prepared by treatment of 50S subunits with 0.4 M Licl (0.4c core) and 0.8 M Licl (0.8c core), respectively. 0.4c cores bind chloramphenicol whereas 0.8c cores do not. The split proteins obtained during the transitions 0.4c --> 0.8c were separated by DEAE-cellulose chromatography and Sephadex G-100 gel filtration. Reconstitution experiments with the fractionated proteins d...

ÐSeveral RGD peptidomimetics have been prepared, in a convergent way, from the common ortho-aminotyrosine template (O-substituted with an anchorage-arm or a methyl group, and aN-substituted with a ̄uorine tag for XPS analysis), and various o-aminoacid derivatives. The most ̄exible compounds have shown a biological activity similar to that of the peptide reference (RGDS) in the platelet aggregat...

In this work, biocompatible ionic liquids based on aminoacids were employed as extractants to separate extremolipases from aqueous streams. First, the influence of aminoacid and dipeptide-based (cholinium glycinate, ChGly, cholinium glycylglycinate, ChGlygly) lipolytic activity a commercial lipase Candida antarctica (CaLB) in-house synthesized extremophilic lipases Thermus thermophilus HB27 (Tt...