The behavior of osteoblast-like cells on various substrates with functional blocking of integrin-β1 and integrin-β3

This study was designed to examine the influence of integrin subunit-β1 and subunit-β3 on the behavior of primary osteoblast-like cells, cultured on calcium phosphate (CaP)-coated and non coated titanium (Ti). Osteoblast-like cells were incubated with specific monoclonal antibodies against integrin-β1 and integrin-β3 to block the integrin function. Subsequently, cells were seeded on Ti discs, either non coated or provided with a 2 μm carbonated hydroxyapatite coating using Electrostatic Spray Deposition. Results showed that on CaP coatings, cellular attachment was decreased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. On Ti, cell adhesion was only slightly affected after a pre-treatment with anti-integrin-β3 antibodies. Scanning electron microscopy showed that on both types of substrate, cellular morphology was not changed after a pre-treatment with either antibody. With quantitative PCR, it was shown for both substrates that mRNA expression of integrin-β1 was increased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. Furthermore, after a pre-treatment with either antibody, mRNA expression of integrin-β3 and ALP was decreased, on both types of substrate. In conclusion, osteoblast-like cells have the ability to compensate to great extent for the blocking strategy as applied here. Still, integrin-β1 and β3 seem to play different roles in attachment, proliferation, and differentiation of osteoblast-like cells, and responses on CaP-coated substrates differ to non coated Ti. Furthermore, the influence on ALP expression suggests involvement of both integrin subunits in signal transduction for cellular differentiation

Biological response to pre-mineralized starch based scaffolds for bone tissue engineering

It is known that calcium-phosphate (Ca-P) coatings are able not only to improve the bone bonding behaviour of polymeric materials, but at the same time play a positive role on enhancing cell adhesion and inducing the differentiation of osteoprogenitor cells. Recently an innovative biomimetic methodology, in which a sodium silicate gel was used as a nucleative agent, was proposed as an alternative to the currently available biomimetic coating methodologies. This methodology is especially adequate for coating biodegradable porous scaffolds. In the present work we evaluated the influence of the referred to treatment on the mechanical properties of 50/50 (wt%) blend of corn starch/ethylene-vinyl alcohol (SEVA-C) based scaffolds. These Ca-P coated scaffolds presented a compressive modulus of 224.6 ± 20.6 and a compressive strength of 24.2 ± 2.20. Cytotoxicity evaluation was performed according ISO/EN 10993 part 5 guidelines and showed that the biomimetic treatment did not have any deleterious effect on L929 cells and did not inhibit cell growth. Direct contact assays were done by using a cell line of human osteoblast like cells (SaOS-2). 3 × 105 cells were seeded per scaffold and allowed to grow for two weeks at 37 ◦C in a humidified atmosphere containing 5% CO2. Total protein quantification and scanning electron microscopy (SEM) observation showed that cells were able to grow in the pre-mineralized scaffolds. Furthermore cell viability assays (MTS test) also show that cells remain viable after two weeks in culture. Finally, protein expression studies showed that after two weeks osteopontin and collagen type I were being expressed by SaOS-2 cells seeded on the pre-mineralized scaffolds. Moreover, alkaline phosphatase (ALP) activity was higher in the supernatants collected from the pre-mineralized samples, when compared to the control samples (non Ca-P coated). This may indicate that a faster mineralization of the ECM produced on the pre-mineralized samples was occurring. Consequently, biomimetic pre-mineralization of starch based scaffolds can be a useful route for applying these materials on bone tissue engineering

Archeologische rapporten nr. 2

In de maanden mei tot en met september 1995 is in de Fransen- en Kuiperstraat in Vlaardingen het rioolstelsel vernieuwd . Het archeologisch onderzoek dat tijdens deze rioleringswerkzaamheden plaatsvond, was een ontdekkingstocht door het bodemarchief van de binnenstad van Vlaardingen . Hoewel bij de aanleg van het vorige riool en ook bij andere graafactiviteiten de bodem in de Fransen- en Kuiperstraat reeds behoorlijk verstoord is geraakt, bleek tijdens het archeologisch onderzoek dat een belangrijk deel hiervan nog intact was, dat wil zeggen niet vergraven. Niet alleen werden dieper gelegen structuren aangetroffen als sloten en waterputten, maar ook vele funderingen en vloeren waarvan de bovenkant soms nog geen dertig cm onder straatniveau lag. Tevens zijn vele afgedankte gebruiksvoorwerpen van de Vlaardingers uit vervlogen tijden teruggevonden

Verslag van het (bouw-)historisch en archeologisch onderzoek

In 2004 is door het Vlaardings Archeologisch Kantoor (VLAK) een opgraving uitgevoerd op de locatie ‘Het Hof' . Dit toponiem verwijst naar de buitenplaats van de familie Van Ruytenburgh en latere ambachtsheren, die hier gelegen was. De locatie staat op de Archeologische Monumentenkaart dan ook aangeduid als ' Terrein van hoge archeologische waarde' . De computerplot, vervaardigd vóór de aanvang van het archeologisch onderzoek, blijkt tamelijk nauwkeurig. Verstoringen ten zuidwesten en westen van het gebouw hebben een gedeelte van het achterterrein vernield, maar de fundamenten van het gebouw en enkele voorzieningen voor het putten, de opslag en afvoer van water konden gedocumenteerd worden

In vitro evaluation of osteoblastic cell adhesion on machined osseointegrated implants

At present the major consideration in planning an implant design is to seek biocompatible surfaces that promote a favorable response from both cells and host tissues. Different treatments of implant surfaces may modulate the adhesion, proliferation and phenotypic expression of osteoblastic cells. For this reason, the aim of the present study was to evaluate the biocompatibility of an implant surface, observing adhesion, cell morphology and proliferation of osteoblast-like cells cultivated on a commercially available titanium dental implant (Titamax Liso®, Neodent, Curitiba, PR, Brazil). The implant samples were immersed into an osteoblast-like cell (Osteo-1) suspension for a period of 24, 48 and 72 hours. After seeding the cells, the samples were prepared for analyses through scanning electron microscopy. Based on the surface analysis, the osteoblastic cells adhered to the machined surface after 24 hours in culture. In 48 hours, the cells spread over the implant surface, and after 72 hours a proliferation of cells with large and flat bodies was observed over the machined implant surface. These results demonstrate that the machined titanium surface studied is biocompatible since it allowed adhesion and proliferation of the osteoblast-like cells, in addition to preserving cell integrity and the morphologic characteristics of cells during the studied period

LAPAROSCOPY TO PREDICT THE RESULT OF PRIMARY CYTOREDUCTIVE SURGERY IN ADVANCED OVARIAN CANCER (LAPOVCA): A MULTICENTRE RANDOMISED CONTROLLED TRIAL

Cervix cance

Cost-effectiveness of laparoscopy as diagnostic tool before primary cytoreductive surgery in ovarian cancer

Objective: To evaluate the cost-effectiveness of a diagnostic laparoscopy prior to primary cytoreductive surgery to prevent futile primary cytoreductive surgery (i.e. leaving >1cm residual disease) in patients suspected of advanced stage ovarian cancer. Methods: An economic analysis was conducted alongside a randomized controlled trial in which patients suspected of advanced stage ovarian cancer who qualified for primary cytoreductive surgery were randomized to either laparoscopy or primary cytoreductive surgery. Direct medical costs from a health care perspective over a 6-month time horizon were analyzed. Health outcomes were expressed in quality-adjusted life-years (QALYs) and utility was based on patient's response to the EQ-5D questionnaires. We primarily focused on direct medical costs based on Dutch standard prices. Results: We studied 201 patients, of whom 102 were randomized to laparoscopy and 99 to primary cytoreductive surgery. No significant difference in QALYs (utility=0.01; 95% CI 0.006 to 0.02) was observed. Laparoscopy reduced the number of futile laparotomies from 39% to 10%, while its costs were € 1400 per intervention, making the overall costs of both strategies comparable (difference € -80 per patient (95% CI -470 to 300)). Findings were consistent across various sensitivity analyses. Conclusion: In patients with suspected advanced stage ovarian cancer, a diagnostic laparoscopy reduced the number of futile laparotomies, without increasing total direct medical health care costs, or adversely affecting complications or quality of life.Roelien van de Vrie, Hannah S. van Meurs, Marianne J. Rutten, Christiana A. Naaktgeboren, Brent C. Opmeer, Katja N. Gaarenstroom, Toon van Gorp, Henk G. Ter Brugge, Ward Hofhuis, Henk W.R. Schreuder, Henriette J.G. Arts, Petra L.M. Zusterzeel, Johanna M.A. Pijnenborg, Maarten van Haaften , Mirjam J.A. Engelen, Erik A. Boss, M. Caroline Vos, Kees G. Gerestein, Eltjo M.J. Schutter, Gemma G. Kenter, Patrick M.M. Bossuyt, Ben Willem Mol, Marrije R. Buis