1.19 Calcium Phosphate Ceramics With Inorganic Additives ☆

The use of inorganic compounds as synthetic growth factors is a promising approach for improving the biological properties of existing synthetic bone graft substitutes such as calcium phosphates. In this article we have described some of the inorganic additives that may improve the capabilities of calcium phosphates, and help bridge the gap toward autograft?s performance known as gold standard for bone regeneration. This article focuses on the specific roles of bioinorganics in processes related to bone formation and resorption and how these modify the biological properties of calcium phosphates, and finally provides insight into the future of this field

Preconception lifestyle intervention in women with obesity and echocardiographic indices of cardiovascular health in their children

Background: Improving maternal lifestyle before conception may prevent the adverse effects of maternal obesity on their children’s future cardiovascular disease (CVD) risk. In the current study, we examined whether a preconception lifestyle intervention in women with obesity could alter echocardiographic indices of cardiovascular health in their children. Methods: Six years after a randomized controlled trial comparing the effects of a 6-month preconception lifestyle intervention in women with obesity and infertility prior to fertility care to prompt fertility care, 315 of the 341 children conceived within 24 months after randomization were eligible for this study. The intervention was aimed at weight loss (≥5% or until BMI < 29 kg/m2). Children underwent echocardiographic assessment of cardiac structure and function, conducted by a single pediatric cardiologist, blinded to group allocation. Results were adjusted for multiple variables including body surface area, age, and sex in linear regression analyses. Results: Sixty children (32 girls, 53%) were included, mean age 6.5 years (SD 1.09). Twenty-four children (40%) were born to mothers in the intervention group. Children of mothers from the intervention group had a lower end-diastolic interventricular septum thickness (−0.88 Z-score, 95%CI −1.18 to −0.58), a lower left ventricle mass index (−8.56 g/m2, 95%CI −13.09 to −4.03), and higher peak systolic and early diastolic annular velocity of the left ventricle (1.43 cm/s 95%CI 0.65 to 2.20 and 2.39 cm/s 95%CI 0.68 to 4.11, respectively) compared to children of mothers from the control group. Conclusions: Children of women with obesity, who underwent a preconception lifestyle intervention, had improved cardiac structure and function; a thinner interventricular septum, lower left ventricle mass, and improved systolic and diastolic tissue Doppler velocities. Despite its high attrition rates, our study provides the first experimental human evidence suggesting that preconception lifestyle interventions may present a method of reducing CVD risk in the next generation. Clinical trial registration: LIFEstyle study: Netherlands Trial Register: NTR1530 (https://www.trialregister.nl/trial/1461). This follow-up study was approved by the medical ethics committee of the University Medical Centre Groningen (METC code: 2008/284)

Generation of a construction planning from a 3D CAD model

In construction planning practice, increasingly 4D CAD system are applied for construction analysis and communication. Normally the planning expert is responsible for relating building components to construction activities. In this article we describe a method for automated generation of the construction planning. An algorithm is presented that derives the construction order from a solid model of the building. Experiences from a pilot study illustrate the differences between the real planning and the generated planning, and they show the limitations of the current implementation. Finally an outlook is presented on a more advanced planning system that includes contractor's specific knowledge for more accurate results

Construction Analysis during the Design Process

4D CAD systems are used by contractors for visually checking the construction process. To enable simulation of the construction process, the construction planner links building components from a CAD model with the activities from a project planning. In this paper we describe a method to generate a project planning directly from a CAD model using basic construction knowledge. A case study is discussed briefly to show the current results and the shortcomings. Finally an outlook is presented on a more advanced implementation that is (also) useful for designers

Ductus arteriosus and failed medical therapy

BACKGROUND: Management of a patent ductus arteriosus (PDA) after pharmacological therapy failure in preterm neonates is controversial and shows marked practice variation. To evaluate which factors motivate the decision to ligate a PDA in clinical practice we examined several clinical and echocardiographic variables. METHODS: We conducted a retrospective single center cohort study. We included infants born at less than 37 weeks of gestation, admitted to our neonatal intensive care between 01.01.2008 and 31.12.2015 with a PDA detected on echocardiography after two or three courses of medical therapy. Logistic regression analyses were used to predict surgical ligation for twelve clinical and nine echocardiographic variables separately. We used the multiple imputation technique for missing values. RESULTS: A total of 89 neonates were included of which forty (45%), underwent surgical ligation of their PDA. In our final multivariate regression model, invasive respiratory support (OR 3.6, 95% CI 1.29-10.03), left atrial/aortic root ratio (OR 5.48, 95% CI 1.66-18.11) and presence of ductal steal (OR 3.82, 95% CI 1.47-9.91) were significant predictors for surgical ligation. The prediction model using clinical and echocardiographic variables explained 9% and 24% of the variability to ligate respectively, indicating significant residual variation due to unmeasured factors. CONCLUSIONS: Our results indicate that invasive respiratory support, increased left atrial/aortic root ratio and the presence of ductal steal were important predictors for surgical ligation in our center. However, this explained only a small proportion of the variability, which emphasizes the need for evidence-based guidelines in the management of preterm neonates after failed pharmacological therapy for a PDA

Development of a shear stress-free microfluidic gradient generator capable of quantitatively analyzing single-cell morphology

Microfluidics, the science of engineering fluid streams at the micrometer scale, offers unique tools for creating and controlling gradients of soluble compounds. Gradient generation can be used to recreate complex physiological microenvironments, but is also useful for screening purposes. For example, in a single experiment, adherent cells can be exposed to a range of concentrations of the compound of interest, enabling high-content analysis of cell behaviour and enhancing throughput. In this study, we present the development of a microfluidic screening platform where, by means of diffusion, gradients of soluble compounds can be generated and sustained. This platform enables the culture of adherent cells under shear stress-free conditions, and their exposure to a soluble compound in a concentration gradient-wise manner. The platform consists of five serial cell culture chambers, all coupled to two lateral fluid supply channels that are used for gradient generation through a source-sink mechanism. Furthermore, an additional inlet and outlet are used for cell seeding inside the chambers. Finite element modeling was used for the optimization of the design of the platform and for validation of the dynamics of gradient generation. Then, as a proof-of-concept, human osteosarcoma MG-63 cells were cultured inside the platform and exposed to a gradient of Cytochalasin D, an actin polymerization inhibitor. This set-up allowed us to analyze cell morphological changes over time, including cell area and eccentricity measurements, as a function of Cytochalasin D concentration by using fluorescence image-based cytometry