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

Borderline tumours of the ovary:Common practice in the Netherlands

Objectives: Discordance between frozen section diagnosis and the definite histopathological diagnosis and the fact that the frozen section result is not always unambiguous, may contribute to differences in clinical practice regarding perioperative treatment and follow-up of borderline ovarian tumours (BOTs) patients amongst gynaecologic oncologists, which may lead to over- and undertreatment. The aim of the study was to map the Dutch gynaecologists' preferred treatment and follow-up strategy in case of BOTs. Methods: A questionnaire was sent to all Dutch gynaecologists involved in ovarian surgery with perioperative frozen section analysis, and the outcomes were assessed using descriptive statistics. Results: Nearly half of the respondents (41.0%) would not perform a staging procedure in case of a BOT. In case of an ambiguous frozen section diagnosis, tending towards invasive carcinoma, a considerable number (sBOT 56.4%; mBOT 30.8%) would perform a lymph node sampling as part of the staging procedure. A relaparotomy/relaparoscopy, to perform a lymph node sampling in case of a serous or mucinous carcinoma after a BOT frozen section diagnosis, would be performed by 97.4% and 48.7% of the respondents, respectively. Conclusions: A considerable number of gynaecologists would perform a staging procedure that is recommended for ovarian cancer in case of an ambiguous BOT frozen section diagnosis, especially for serous tumours. In addition, nearly all gynaecologists would perform a second procedure including a lymph node sampling in case of a serous invasive carcinoma after a BOT frozen section diagnosis, which applies to half of the gynaecologists in case of a mucinous carcinoma. Keywords: Borderline tumours of the ovary, Staging procedure, Frozen section analysis, Questionnaire, Gynaecologic oncologist, Semi-specialized gynaecologist

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

Efficiency of stress-adaptive traits chlorophyll fluorescence and membrane thermo- stability in wheat under high temperature

Despite developments in targeted gene sequencing and whole-genome analysis techniques, the robust detection of all genetic variation, including structural variants, in and around genes of interest and in an allele-specific manner remains a challenge. Here we present targeted locus amplification (TLA), a strategy to selectively amplify and sequence entire genes on the basis of the crosslinking of physically proximal sequences. We show that, unlike other targeted re-sequencing methods, TLA works without detailed prior locus information, as one or a few primer pairs are sufficient for sequencing tens to hundreds of kilobases of surrounding DNA. This enables robust detection of single nucleotide variants, structural variants and gene fusions in clinically relevant genes, including BRCA1 and BRCA2, and enables haplotyping. We show that TLA can also be used to uncover insertion sites and sequences of integrated transgenes and viruses. TLA therefore promises to be a useful method in genetic research and diagnostics when comprehensive or allele-specific genetic information is needed

Archeologische rapporten nr. 5

In Vlaardingen werd tijdens een opgraving door het bureau archeologie Gemeente Vlaardingen een boemerang gevonden nabij een inheems-Romeinse duiker. Als gevolg van de goede conserveringsomstandigheden zijn voor zover bekend in Nederland tot nog toe drie boemerangs gevonden, daterend uit de IJzertijd (1) en Romeinse Tijd (2)

A perspective-based simulation game to explore future pathways of an interacting water-society system

In this article, the authors address the challenge of including societal responses, society-environment interactions, discontinuity, and surprise in environmental scenario analysis. They do so through developing and testing a perspective-based simulation game for a typical Dutch river stretch. Concepts deriving from Cultural Theory, the Advocacy Coalition Framework, and Transition Theory provide the input for the game design. Players take on the role of water managers, responding to events and developments in the water-society system under specific realizations of a climate scenario. Responses include the choice for specific river management options, changing coalition perspectives, and changes in advocacy coalition membership. A pilot case study shows that the simulation game is a useful tool to explore possible future river management dynamics. It generates relevant insights in the water management strategies that may be chosen under future conditions, the possible drivers underlying future societal perspective change, and the way advocacy coalitions may interact. As such, the simulation game offers great potential for developing and assessing policy relevant climate adaptation pathways, in which water-society interaction, discontinuity, and surprise is taken explicitly into account. The main challenges for future research include reducing game complexity, better representing changes in the advocacy coalitions' strengths, and exploring more fundamental societal perspective shift