Micro‑dimpled surface atelocollagen maintains primary human hepatocytes in culture and may promote their functionality compared with collagen coat culture.

Primary human hepatocytes (PHHs) are the gold standard for drug development procedures; however, maintaining functional PHHs in vitro is challenging in conventional collagen‑coated cultures. In the present study, we developed a new scaffold comprising high amounts (≥1 mg/cm2) of atelocollagen exposed to ultraviolet radiation to induce cross‑linking and improve stability. Scanning and transmission electron microscopy revealed a micro‑dimpled surface (MDS) scaffold composed of randomly arranged atelocollagen fibrils.

Optimal bovine collagen concentration to achieve tracheal epithelial coverage of collagen sponges.

Objectives/hypothesis: Artificial tracheas prepared using a collagen sponge and polypropylene mesh have been implanted in patients who received tracheal resections, but epithelialization in the reconstructed area is slow. We determined the optimal bovine atelocollagen concentration necessary for the rapid and complete tracheal epithelial coverage of collagen sponge implants.

Study Design: Preliminary animal experiment.

A novel mechanism of autolysis in Helicobacter pylori: possible involvement of peptidergic substances.

Background: Helicobacter pylori survival in a hostile acidic environment is known to be caused by its production of urease, which is not released by known secretion pathways. It has been proposed that H. pylori cells undergo spontaneous autolysis during cultivation and that urease becomes surface-associated only concomitant with bacterial autolysis.

Hrs, a mammalian master molecule in vesicular transport and protein sorting, suppresses the degradation of ESCRT proteins signal transducing adaptor molecule 1 and 2.

The degradation and sorting of cytoplasmic and cell-surface proteins are crucial steps in the control of cellular functions. We previously identified three mammalian Vps (vacuolar protein sorting) proteins, Hrs (hepatocyte growth factor-regulated tyrosine kinase substrate) and signal transducing adaptor molecule (STAM) 1 and -2, which are tyrosine-phosphorylated upon cytokine/growth factor stimulation. Hrs and the STAMs each contain a ubiquitin-interacting motif and through formation of a complex are involved in the vesicle transport of early endosomes.