Biomedical subjects

Jirí Vacík

Publications and source records attributed to Jirí Vacík.

4 recordsLinked to original sources

PubMed2006

Macroporous hydrogels based on 2-hydroxyethyl methacrylate. Part 5: hydrolytically degradable materials.

Macroporous hydrogels based on 2-hydroxyethyl methacrylate, 2-ethoxyethyl methacrylate and N-(2-hydroxypropyl)methacrylamide, methacrylic acid and [2-(methacryloyloxy)ethyl]trimethylammonium chloride crosslinked with N,O-dimethacryloylhydroxylamine were prepared. Hydrogels were degraded in a buffer of pH 7.4. Completely water-soluble polymers were obtained over time periods ranging from 2 to 40 days. The process of degradation was followed gravimetrically and by optical and electron microscopy. In vivo biological tests with hydrogels based on copolymers of 2-ethoxyethyl methacrylate/N-(2-hydroxypropyl)methacrylamide were performed.

Absorbable Implants↗

PubMed2003

Reconstruction of epidermis by grafting of keratinocytes cultured on polymer support--clinical study.

BACKGROUND: Extensive wound coverage still represents a challenge for contemporary medicine. We demonstrate the results of a clinical trial of the grafting of cultured keratinocytes directly on a polymer cultivation support in the treatment of skin defects in seriously burned patients and in patients with trophic ulcers. METHODS: Wound closure was evaluated clinically. The morphology and phenotypic pattern of the reconstructed epidermis, including the basal lamina, as well as the presence of Langerhans cells, were evaluated immunocytochemically using a panel of monoclonal antibodies. RESULTS: All layers of the reconstructed epidermis were normally differentiated (cytokeratin immunocytochemistry). The basal lamina contained collagen type IV and laminin. The reconstructed epidermis was extensively colonized by Langerhans cells. CONCLUSIONS: The results of the described technology are encouraging, especially in patients after a burn injury. The described procedure is suitable for the treatment of skin defects in clinical practice.

Adult↗

PubMed2002

Dolichos biflorus agglutinin-binding site expression in basal keratinocytes is associated with cell differentiation.

A basal layer of squamous epithelia such as epidermis contains stem cells, transit amplifying cells as well as postmitotic differentiating cells. A detailed knowledge of the transition among these cell types in the course of epidermal renewal is important. It would help in better understanding of many pathological processes, including cancer, and in employment of epidermal cells for therapeutic purposes. In this study we analyzed the possible role of Dolichos biflorus agglutinin (DBA)-reactive alpha-N-acetylgalactosamine glycosylation in behavior of the human epidermal basal cells under in vivo and in vitro conditions. The data received from porcine epidermis were also included. Part of basal cells was positive for DBA-binding sites and these cells exhibited a lower presence of beta1 integrin in their basal surface connected to the basement membrane. The perinuclear Golgi-like accumulation of beta1 integrin was observed in some cultured keratinocytes. The co-localization of integrin with DBA-binding sites and 58 kDa protein suggests that alpha-N-acetylgalactosamine glycosylation could be related to beta1 integrin retention in the endoplasmatic reticulum Golgi intermediate compartment (ERGIC) at the beginning of the secretory pathway. The lack of anchorage in culture elevated the number of DBA-binding site positive cells without significant influence on cell growth when cells isolated directly from epidermis were employed in study. Some role of DBA-reactive glycoligand expressions in a suprabasal movement of differentiated basal cells can be hypothesized.

Acetylgalactosamine↗

PubMed2002

Evaluation of biocompatibility of the copolymer of 2-hydroxyethyl methacrylate with 2-(methylsulfanyl)ethyl methacrylate.

This study compares subcutaneous and intracerebral biocompatibilty of two hydrogels: copolymer of 2-hydroxyethyl methacrylate with 2-(methylsulfanyl)ethyl methacrylate and poly(2-hydroxyethyl methacrylate) as reference polymer. The experimental copolymer was more biologically inert than poly(2-hydroxyethyl methacrylate) in both the studied parameters, hence the former material is a suitable candidate for biomedical application.

Journal Article↗