Three-dimensional Printing of Biomimetic Titanium Mimicking Trabecular Bone Induces Human Mesenchymal Stem Cell Proliferation: An In-vitro Analysis.

STUDY DESIGN: In vitro analysis. OBJECTIVE: The aim of this study was to assess the effect of three-dimensional (3D) printing of porous titanium on human mesenchymal stem cell (hMSC) adhesion, proliferation, and osteogenic differentiation. SUMMARY OF BACKGROUND DATA: A proprietary implant using three-dimensional porous titanium (3D-pTi) that mimics trabecu-lar bone structure, roughness, porosity, and modulus of elasticity was created (Ti-LIFE technology™, Spineart SA Switzerland). Such implants may possess osteoinductive properties augmenting fusion in addition to their structural advantages. However, the ability of 3D-pTi to affect in vitro cellular proliferation and osteogenic differentiation remains undefined. METHODS: Disks of 3D-pTi with a porosity of 70% to 75% and pore size of 0.9 mm were produced using additive manufacturing technology. 2D Ti6Al4V (2D-Ti) and 2D polyetheretherketone (2D-PEEK) disks were prepared using standard manufacturing process. Tissue culture plastic (TCP) served as the control surface. All discs were characterized using 2D-micros-copy, scanning electron microscopy (SEM), and x-ray micro-computed tomography. Forty thousand hMSCs were seeded on the disks and TCP and cultured for 42 days. hMSC morphology was assessed using environmental SEM and confocal imaging following phalloidin staining. hMSC proliferation was evaluated using DNA fluorescent assay. hMSC differentiation was assessed using RT-qPCR for genes involved in hMSC osteogenic differentiation and biochemical assays were performed for alkaline phosphatase activity (ALP) and calcium content. RESULTS: 3D-pTi lead to a higher cell number as compared to 2D-Ti and 2D-PEEK at D21, D28 and D42. ALP activity of hMSCs seeded into 3D-pTi scaffolds was as high as or higher than that of hMSCs seeded onto TCP controls over all time points and consistently higher than that of hMSCs seeded onto 2D-Ti scaffolds. However, when ALP activity was normalized to protein content, no statistical differences were found between all scaffolds tested and TCP controls. CONCLUSION: 3D-pTi provides a scaffold for bone formation that structurally mimics cancellous bone and improves hMSC adhesion and proliferation compared to 2D-Ti and PEEK.

Khat use and intimate partner violence in a refugee population: a qualitative study in Dollo Ado, Ethiopia.

BACKGROUND: Intimate partner violence (IPV) is the most common form of gender-based violence affecting women and girls worldwide and is exacerbated in humanitarian crises. There is evidence that substance use is associated with male perpetration of IPV. Consumption of khat -a plant containing amphetamines traditionally chewed in the horn of Africa and legal in some countries including Ethiopia-may increase risk of IPV toward women. This analysis aimed to assess perceptions on khat use among Somali refugees in Dollo Ado, Ethiopia and its association with IPV to inform an IPV and HIV prevention intervention. METHODS: A descriptive qualitative study comprising individual interviews (n = 30) and focus group discussions (n = 10) was conducted in Bokolmayo refugee camp in Dollo Ado, Ethiopia in October 2016. A purposive sample of male and female Somali refugees, religious and community leaders, and service providers (n = 110 individuals; 44 women and 66 men) was included. Trained interviewers from the camp conducted the interviews and discussion, which were audio recorded, transcribed and translated. A content analysis was conducted on coded excerpts from the transcripts to identify factors contributing to IPV toward women, including khat use. RESULTS: Participants reported that displacement has resulted in limited employment opportunities for men and increased idle time, which has led to increased khat use among men as a coping mechanism. Male khat use was perceived to be associated with perpetration of physical and sexual IPV through several mechanisms including increased anger and aggression and enhanced sexual desire. Khat use also contributes to intra-marital conflict as money allocated for a household is spent on purchasing khat. CONCLUSION: Khat use should be addressed as part of IPV prevention programming in this context. Livelihood interventions and other strategies to improve economic conditions, should be explored in collaboration with refugee camp authorities and community leaders as a potential avenue to mitigate the impact of khat use on women and families.