Proliferation and differentiation of osteoblasts on Biocement D modified with collagen type I and citric acid.

In this study, the proliferation and differentiation of rat calvarial osteoblasts cultured on either (1) calcium-phosphate bone cement Biocement D, (2) Biocement D with 2.5% (w/w) mineralized collagen type I, or (3) Biocement D with 2.5% (w/w) mineralized collagen type I and 3% (w/w) citric acid were investigated.

Phosphoserine--a convenient compound for modification of calcium phosphate bone cement collagen composites.

Temporary bone replacement materials on the basis of calcium phosphates and hydroxyapatite (HAP) are used in surgery for filling bone defects. Components which are able to control the nucleation and crystal growth of HAP through their functional groups and which can additionally activate bone cells may be helpful in the development of materials with enhanced remodelling in vivo. In this study, the influence of O-phospho-L-serine (PS) on the materials properties of calcium phosphate bone cement composites was investigated.

Modification of Ti6AL4V surfaces using collagen I, III, and fibronectin. II. Influence on osteoblast responses.

Responses of osteoblastic cells are influenced by morphology and composition of the extracellular matrix, and this fact has been used to improve the biological acceptance of implants by modifying the surfaces with components of the extracellular matrix (ECM). In this study, the effect of the collagen types I and III on adhesion, proliferation, and differentiation was studied, using primary osteoblastic cells from rat calvariae. Differences in alkaline phosphatase activity (ALP) and collagen synthesis were observed between differently composed collagen coatings.

Transforming growth factor beta1 immobilized adsorptively on Ti6Al4V and collagen type I coated Ti6Al4V maintains its biological activity.

Titanium and titanium alloys are often used for orthopedic and dental implants. Osseointegration of Ti6Al4V may be improved not only by precoating of the surface with extracellular matrix proteins like collagen type I but also by additional immobilization of growth factors. In the present study, transforming growth factor beta1 (TGF-beta1) which is known as an inducer of collagen synthesis was immobilized adsorptively on uncoated and collagen type I coated Ti6Al4V surfaces.

Proliferation and differentiation of rat calvarial osteoblasts on type I collagen-coated titanium alloy.

Several attempts have been made to improve osseointegration of titanium alloy as an implant material by modification of its surface. In the present study, proliferation, differentiation, and mineralization of osteoblasts on type I collagen-coated Ti6Al4V were investigated. The activity of alkaline phosphatase and the accumulation of calcium by osteoblasts grown on titanium alloy were significantly higher compared to cells grown on polystyrene.

Changes in xylosyltransferase activity and in proteoglycan deposition in bleomycin-induced lung injury in rat.

Several lines of evidence support the hypothesis of the involvement of altered proteoglycan deposition in the development of lung diseases. UDP-D-xylose: core protein beta-D-xylosyltransferase (UDP-xylosyltransferase; EC 2.4.

Purification and some properties of UDP-xylosyltransferase of rat ear cartilage.

UDP-xylosyltransferase (UDP-D-xylose:proteoglycan core protein beta-D-xylosyltransferase EC 2.4.2.

Home self-assessment and self-treatment of obsessive-compulsive disorder using a manual and a computer-conducted telephone interview: replication of a UK-US study.

Background: This open study replicates and extends previous pilot work with BT STEPS, a self-therapy system to assess and treat obsessive-compulsive disorder (OCD) through exposure and ritual prevention.

Method: 21 OCD patients entered this open trial, using a self-guiding manual and any Touch-Tone telephone to access computer-driven interviews via an Interactive Voice Response system. The patients also used the system to rate progress on rating scales.

Characterisation of caveolins from cartilage: expression of caveolin-1, -2 and -3 in chondrocytes and in alginate cell culture of the rat tibia.

This study was performed to determine if rat articular chondrocytes express caveolin, the structural protein of caveolae, and to determine differences in the distribution of the caveolin subtypes 1, 2 and 3 in knee joints of newborn and adult rats. All three subtypes of caveolin were detected in adult cartilage by immunocytochemical staining. In newborn rats, only caveolin-1 was found in the hyaline cartilage.

Loss of immunoreactivity for RTI40, a type I cell-specific protein in the alveolar epithelium of rat lungs with bleomycin-induced fibrosis.

After lung injury, the epithelial cells lining the alveolar surface in rat lung show an altered distribution of several membrane proteins. Pulmonary fibrosis was induced by intratracheal administration of bleomycin into the lung of rats and the distribution of RTI40, a recently detected alveolar epithelial type I cell antigen, was examined, as well as the relationship between RTI40 and a type I cell-specific antigen recognized by the monoclonal antibody MEP-1 and the type I cell-binding lectin Bauhinia purpurea in serial sections and double stainings. Loss of RTI40 protein was observed in fibrotic lungs, particularly in areas with obliteration of alveoli.

Home self-assessment of obsessive-compulsive disorder. Use of a manual and a computer-conducted telephone interview: two UK-US studies.

Background: Two studies tested whether subjects with obsessive-compulsive disorder could successfully use BT STEPS, a computer-aided system, to perform self-assessment for self-treatment of obsessive-compulsive disorder by exposure and ritual prevention.

Method: Subjects were given a self-guiding manual and could use a touch-tone telephone to access computer-controlled Interactive Voice Response interviews at their convenience from home. Using the BT STEPS system, patients rated themselves and worked out a plan for individually tailored self-exposure therapy.

Self-administered psychotherapy for depression using a telephone-accessed computer system plus booklets: an open U.S.-U.K. study.

Objective: To evaluate the efficacy and acceptability of a self-help program for mild-to-moderate depression that combined treatment booklets and telephone calls to a computer-aided Interactive Voice Response (IVR) system.

Method: In an open trial, 41 patients from Boston, Massachusetts; Madison, Wisconsin; and London, England, used COPE, a 12-week self-help system for depression. COPE consisted of an introductory videotape and 9 booklets accompanied by 11 telephone calls to an IVR system that made self-help recommendations to patients based on information they entered.

Transforming growth factor-beta1-induced activation of the Raf-MEK-MAPK signaling pathway in rat lung fibroblasts via a PKC-dependent mechanism.

In fibroblasts transforming growth factor-beta1 (TGF-beta1) regulates cell proliferation and turnover of macromolecular components of the extracellular matrix. Here, intracellular signaling events in growth-inhibited embryonic rat lung fibroblasts (RFL-6) upon stimulation with TGF-beta1 were investigated. TGF-beta1 rapidly induced the activation of c-Raf-1, MEK-1, and MAPK p42 and p44.

Self-treatment for obsessive compulsive disorder using a manual and a computerized telephone interview: a U.S.-U.K. study.

Bt steps is a patient-centered behavioral therapy program that uses a manual and a computer-driven interactive voice response system to assess and treat obsessive compulsive disorder. This nine-step program contains a self-assessment module and a self-treatment module that provides teaching on exposure and ritual prevention. The patient reads about the steps in a manual and then uses a touch-tone telephone to contact the program, in which a recorded voice conducts the interview.

Proteinases and proteinase inhibitors during the development of pulmonary fibrosis in rat.

Changes in the activities of several proteinases and their inhibitors were investigated during the development of bleomycin-induced pulmonary fibrosis in rat. Studies on the proteinase-anti-proteinase-ratio may contribute to the understanding of the mechanism of the development of pulmonary fibrosis and may help to develop therapeutic strategies to prevent tissue damage by proteolytic attack. In the acute inflammatory period the activity of metalloelastase in lung tissue increased by about 10-fold.

Loss of caveolin expression in type I pneumocytes as an indicator of subcellular alterations during lung fibrogenesis.

Caveolin is a major structural protein of caveolae, also known as plasmalemmal vesicles, which are particularly abundant in type I pneumocytes and capillary endothelial cells of lung parenchyma. Here we demonstrate that caveolin expression in the alveolar epithelium of rats and mini pigs is strikingly downregulated after irradiation-induced lung injury. Indirect immunoperoxidase staining with polyclonal anti-caveolin antibodies, confirmed by double fluorescence studies with type I cell-specific monoclonal anti-cytokeratin antibodies or lectins, revealed a dramatic loss of caveolin immunoreactivity in type I pneumocytes.

Cellular distribution of c-Jun and c-Fos in rat lung before and after bleomycin induced injury.

C-Jun and c-Fos transcription factors have been associated with enhanced cellular proliferation. We studied their cellular distribution in normal and fibrotic rat lung. Pulmonary fibrosis was induced by intratracheal administration of bleomycin.

Autophosphorylation-inactivation site of hexokinase 2 in Saccharomyces cerevisiae.

Hexokinase 2 from Saccharomyces cerevisiae is phosphorylated in vivo at serine-15 [Kriegel et al. (1994) Biochemistry 33, 148-152] and undergoes ATP-dependent autophosphorylation-inactivation in vitro when incubated in the presence of D-xylose [Fernandez et al. (1988) J.

Transforming growth factor-beta1 induces activation of Ras, Raf-1, MEK and MAPK in rat hepatic stellate cells.

The transdifferentiation of hepatic stellate cells into myofibroblast-like cells and the proliferation of the transdifferentiated cells are controlled by TGF-beta1. Little is known about the intracellular signal transducers of TGF-beta1. In this paper we show that in cultured hepatic stellate cells TGF-beta1 induces activation of Ras, Raf-1, MEK and MAPK p42 and p44.

Upregulation of gap junction protein connexin43 in alveolar epithelial cells of rats with radiation-induced pulmonary fibrosis.

The degree of immunoreactive connexin43 (C x 43) in rat lung was evaluated during the development of radiation-induced pulmonary fibrosis in rat by a double immunofluorescence technique using polyclonal antisera to Cx43 and monoclonal antibodies to cytokeratins on cryostat sections. In normal rat lungs, Cx43 was detected in pneumocytes type II and I, in large blood vessel endothelia, in peribronchial smooth muscle cells, and in some peribronchial and perivascular interstitial cells. As early as 1 week after irradiation, enhanced immunoreactivity for Cx43 in the epithelial cells was detected.