Release of Magnetic Nanoparticles From Cell-Encapsulating Biodegradable Nanobiomaterials

The future of tissue engineering requires development of intelligent biomaterials using nanopartides. Magnetic nanopartides (MNPs) have several applications in biology and medicine; one example is Food and Drug Administration (FDA)-approved contrast agents in magnetic resonance imaging. Recently, MNPs have been encapsulated within cell-encapsulating hydrogels to create novel nanobiomaterials (i.e., M-gels), which can be manipulated and assembled in magnetic fields. The M-gels can be used as building blocks for bottom-up tissue engineering to create 3D tissue constructs. For tissue engineering applications of M-gels, it is essential to study the release of encapsulated MNPs from the hydrogel polymer network and the effect of MNPs on hydrogel properties, including mechanical characteristics, porosity, swelling behavior, and cellular response (e.g., viability, growth). Therefore, we evaluated the release of MNPs from photocrosslinkable gelatin methacrylate hydrogels as the polymer network undergoes biodegradation using inductively coupled plasma atomic emission spectroscopy. MNP release correlated linearly with hydrogel biodegradation rate with correlation factors (Pearson product moment correlation coefficient) of 0.96 +/- 0.03 and 0.99 +/- 0.01 for MNP concentrations of 1% and 5%, respectively. We also evaluated the effect of MNPs on hydrogel mechanical properties, porosity, and swelling behavior, as well as cell viability and growth in MNP-encapsulating hydrogels. Fibroblasts encapsulated with MNPs in hydrogels remained viable (>80% at t = 144 h) and formed microtissue constructs in culture (t = 144 h). These results indicated that MNP-encapsulating hydrogels show promise as intelligent nanobiomaterials, with great potential to impact broad areas of bioengineering, including tissue engineering, regenerative medicine, and pharmaceutical applications.Wo

Child mental health and maternal depression history in Pakistan

Purpose We address the significant gaps in knowledge of prevalence and correlates of child mental health (CMH) problems outside of high income countries. We describe the prevalence of CMH problems and their correlates with a focus on the association with maternal depression in a sample of seven-year-old children in rural Pakistan. Methods This study was nested in a long-term follow-up of a perinatal depression intervention together with a reference group of non-depressed women, yielding a population representative sample. The Total Difficulties (TD) and component scores of the Strength and Difficulties Questionnaire (SDQ) were used to measure emotional and behavioral difficulties. Results The mean SDQ TD score was 10.6 (standard deviation = 8.3), with 12.5 % of children categorized as ?abnormal? using standard cutoffs. Boys had a roughly 1 point higher (worse) SDQ TD score than girls (p value = 0.04). Children of mothers who were depressed prenatally as well as currently had SDQ TD scores 2.87 points higher than children whose mothers were not depressed at either time point (p value < 0.01). This association was stronger for boys. There was no evidence of elevated SDQ TD score among children whose mothers were depressed only prenatally or only currently. Some deviations from this pattern were observed with specific components of the SDQ. Conclusions In this low resource, South Asian setting, we found evidence of elevated levels of emotional and behavioral problems, highlighting the need for effective interventions. Given the strong association of CMH with maternal depression, any intervention efforts should give strong consideration to maternal mental health