Interactions of oxidatively modified calf skin collagen with platelets and phagocytes.

Objectives: The effects of non-modified and oxidatively modified calf skin collagen type I on platelet aggregation and the oxidative burst of phagocytes were examined in the framework of a general hypothesis that collagen, platelets and phagocytes cooperate to modulate the oxidative burst of phagocytes and the extent of oxidative stress.

Materials And Methods: Calf skin collagen type I was subjected to oxidative modification by hydrogen peroxide or hydroxyl radical. Thermal denaturation of collagen was performed in a spectrophotometer equipped with a temperature gradient device.

Fibroblast growth factor inhibits interferon gamma-STAT1 and interleukin 6-STAT3 signaling in chondrocytes.

Activation of fibroblast growth factor receptor 3 (FGFR3) leads to attenuation of cartilage growth. The members of the STAT family of transcription factors are believed to participate in FGFR3 signaling in cartilage, however the molecular mechanism of this action is poorly understood. Here, we demonstrate that a chronic FGF stimulus leads to accumulation of STAT1, 3, 5 and 6, evident in both in vitro chondrocyte model and murine limb explant cultures.

C-natriuretic peptide: an important regulator of cartilage.

Over the past several years, the C-natriuretic peptide (CNP) has emerged as an important regulator of cartilage homeostasis and endochondral bone growth. In mice, genetic ablation of CNP or its cognate receptor NPRB results in marked dwarfism. When a downstream component of CNP signaling, protein kinase-G II (PKGII), is removed from cartilage, the mice have disturbed chondrocyte proliferation and cartilage matrix production.

Isolation, cultivation and identification of Borrelia burgdorferi genospecies from Ixodes ricinus ticks from the city of Brno, Czech Republic.

A total of 305 ticks (21 larvae, 243 nymphs, 19 females and 22 males) were collected by flagging of vegetation in suburban woods of Pisarky Park (city of Brno) from July to October 2002. The midgut of each tick was dissected out and transferred individually into BSK-H medium. After cultivation, all specimens were examined by dark-field microscopy (DFM) for the presence of borreliae.

Simple, mammalian cell-based assay for identification of inhibitors of the Erk MAP kinase pathway.

The Erk MAP kinase pathway contributes to tumor development and thus represents an important therapeutic target. Several inhibitors of the Erk pathway are presently being evaluated in clinical trials for cancer, but show limited efficiency thus warranting discovery of more potent inhibitors. We have developed a novel mammalian cell-based assay that should facilitate the identification of such compounds by screening molecular libraries.