PROPERTIES OF CONCRETE CONTAINING CRUSHED LIMESTONE AS TOTAL REPLACEMENT OF NATURAL SAND AND RECYCLED ENGINE OIL

The rapid growth in the construction industry at the global level has made concrete the most widely used construction material throughout the world. Accordingly, the consumption of natural sand which is one the main raw material constituent of concrete is continuously growing. The demand for river sand is highly increasing due to its scarcity in the market. Manufactured sand produced by crushed rock is being considered as an appropriate alternative to replace river sand in concrete. In recent years, there is a growing interest in the use of crushed sand obtained from limestone quarries in some countries where river sand is not widely available”. The objective of this study is to investigate the effect of total replacement of the natural sand by fine aggregates obtained from crushed limestone. However, it needs more research on the crushed stone fine aggregates to reveal its engineering properties prior to utilization in concrete. Another objective of this study is to study the effect of using the waste engine oil as partial replacement of water reducing admixture. The use of waste engine oil in concrete is beneficial for the environment. It is to be noted that some countries are recycling this used oil but others are throwing it in the sea and harming the marine life. In this paper, different combinations and grading of fine lime stone and coarse aggregates were tried in order to attain the optimal proportion that provide an acceptable concrete performance in terms of workability and compressive strength. Also, different percentages of admixture replacement ranging from zero to one hundred percent of the used engine oil were tried in the selected optimal mixture proportion. The final selected proportion using engine oil and crushed limestone could be considered as an economical solution and friendly environmental concrete product

Biomimetic PLGA 3D Scaffold Potentiate Amniotic Epithelial Stem Cells Biological Capability for Tendon Tissue Engineering Applications

INTRODUCTION: Tendon tissue engineering represents a promising solution to deal with tendinopathies and aims to develop effective implantable 3D biomimetic scaffolds with ideally native tissue’s physical, mechanical, biological, and functional qualities. These constructs can be engineered with stem cells to potentiate their teno-inductive and immunomodulatory properties (El Khatib, Mauro, Di Mattia, et al., 2020; El Khatib, Mauro, Wyrwa, et al., 2020; Russo et al., 2020). In this context, amniotic epithelial stem cells (AECs) have recently received much attention in the field of regenerative medicine due to their capacity to differentiate into the tenogenic lineage and to their immunomodulatory profile (Barboni et al., 2012, 2018; Mauro et al., 2016). The focus of this research was to create bundle tendon-like PLGA 3D scaffolds, which mimic tendon macro and micro-architecture and biomechanics, and to assess their impacts on AECs’ biological potential. METHODS: PLGA fleeces, with highly aligned fibers, were fabricated via electrospinning technique through a rotatory collector. The obtained fleeces were then wrapped manually to form 3D tendon-like scaffolds, which were evaluated in terms of structure, mechanical characteristics, and biological influence on AECs by conducting in vitro experiments. Indeed, ovine AECs, seeded on the PLGA 3D scaffolds and fleeces, were compared for their morphological changes and for the cytoplasmic expression of TNMD, a mature tendon protein, respect to cells cultured on Petri dishes (CTR), after 48h and 7d of culture through a confocal microscope. Moreover, the teno-differentiative potential and immunomodulatory properties of the produced constructs were assessed by analyzing the gene expression of tendon related markers (early: SCX, late: COL1 and TNMD) and of anti- (IL10) and pro- (IL12) inflammatory cytokines respectively. Moreover, the present research evaluated YAP protein activation in the engineered AECs through immunofluorescence assay by assessing its cellular localization. RESULTS: The produced PLGA 3D scaffolds, analyzed though a scanning electron microscope, showed high fiber alignment, which closely resemble the architecture, both macroscopically and microscopically, and the biomechanical properties of native tendon tissue. AECs seeded on the produced constructs exhibited an elongated tenocyte-like morphology already after 24 hours, while AECs cultivated on petri dishes (CTR) retained their characteristic polygonal morphology. The engineered AECs' phenotypic change was also confirmed by visualizing the cytoplasmic expression of TNMD protein and supported by tendon-related genes (SCX, COL1, and TNMD) upregulation at 7-day culture respect to CTR cells (p<0.05), which showed no TNMD protein expression or significant increase in tendon-related genes. Moreover, AECs seeded on 3D PLGA scaffolds showed an anti-inflammatory profile, with a significant higher IL10/IL12 ratio respect to the CTR (p<0.05). Finally, 3D scaffolds with highly aligned fibers stimulated AECs in terms of cell cytoskeleton stress, activating their mechanosensitive YAP pathway by significantly increasing YAP nuclear localization compared to the CTR (p<0.05), in which YAP was instead localized in the cytoplasm. DISCUSSION & CONCLUSIONS: Overall, these results support the biomimicry of the fabricated scaffolds in terms of structure and biomechanics and reveal their great teno/immuno-inductive potential and mechanosensing stimulus on AECs, thus standing biomimetic PLGA 3D scaffolds as a potential candidate for tendon regeneration

Children Immunization App (CIMA): A Non-randomized Controlled Trial Among Syrian Refugees in Zaatari Camp, Jordan

Approximately 20 million children are not vaccinated, especially among refugees. There is a growing access to smartphones, among refugees, which can help in improving their vaccination. We assessed the impact of an app for the vaccination follow-up visit among refugees in Jordan. We developed an app and tested it through a non-randomized trial at the Zaatari refugees camp in Jordan. The study was conducted during March – December 2019 at three vaccination clinics inside the camp. The study included two study groups (intervention and control groups) for refugees living at the camp. The intervention group included parents who own an Android smartphone and have one newborn that require between one and four first vaccination doses and they accepted to participate in the study, during their regular visit to the vaccination clinics. The control group was for the usual care. We compared both study groups for returning back to one follow-up visit, using Kaplan-Meier survival analysis. We recruited 936 babies (n = 471; 50.3% in the intervention group, both study groups were similar at baseline). The majority of mothers were literate (94.2%) with a median age of 24. The majority of the babies had a vaccination card (n= 878, 94%). One quarter (26%) of mother-babies pairs of the intervention group came back within one week (versus 22% for control group); When it comes to lost-follow-up, 22% and 28% did not have a history of returning back (intervention and control groups respectively, <p = 0.06) (Relative risk reduction: 19%). The Kaplan-Meier Survival Analysis showed a statistically significant progressive reduction in the duration of coming back late for the follow-up vaccine visit. We tested a vaccination app for the first time, in a refugee population setting. The app can be used as a reminder for parents to come back on time for their children’s vaccine follow-up visits

Critical care nurses' experiences during the Illness of family members : a qualitative study

Introduction: A loved one's hospitalization in a critical care unit is a traumatic experience for families. However, because of their status and professional competence, a family member who is also a critical care nurse has additional obstacles and often long-term consequences. Objectives: To describe the experiences of critical care nurse-family members when a loved one is admitted to a critical care unit at the Hotel-Dieu de France hospital. Methods: A qualitative path based on van Manen's hermeneutic phenomenology combining both descriptive and interpretive models were adopted. Results: The lived experience of critical care nurses in providing care for their family members admitted into the same critical care were summarized in five themes. Nurses were torn between roles, consisting of confounding roles, their registered nurse status, and watchfulness. The lived experience of critical care nurses in providing care for their family members admitted into the same critical care was summarized into specialized knowledge that included a double-edged sword of seeking information and difficulty delivering the information. Critical nurses compete for expectations, including those placed on self and family members, resulting in emotional and personal sacrifice while gaining insight into the experiences. Conclusions: Critical care nurse-family members have a unique experience compared to the rest of the family, necessitating specialized care and attention. Increased awareness among healthcare providers could be a start in the right direction

Tendon Healing Response Is Dependent on Epithelial–Mesenchymal–Tendon Transition State of Amniotic Epithelial Stem Cells

Tendinopathies are at the frontier of advanced responses to health challenges and sectoral policy targets. Cell‐based therapy holds great promise for tendon disorder resolution. To verify the role of stepwise trans‐differentiation of amniotic epithelial stem cells (AECs) in tendon regeneration, in the present research three different AEC subsets displaying an epithelial (eAECs), mesenchymal (mAECs), and tendon‐like (tdAECs) phenotype were allotransplanted in a validated experimental sheep Achilles tendon injury model. Tissue healing was analyzed adopting a comparative approach at two early healing endpoints (14 and 28 days). All three subsets of transplanted cells were able to accelerate regeneration: mAECs with a lesser extent than eAECs and tdAECs as indicated in the summary of the total histological scores (TSH), where at day 28 eAECs and tdAECs had better significant scores with respect to mAEC‐treated tendons (p &lt; 0.0001). In addition, the immunomodulatory response at day 14 showed in eAEC‐transplanted tendons an upregulation of pro‐regenerative M2 macrophages with respect to mAECs and tdAECs (p &lt; 0.0001). In addition, in all allotransplanted tendons there was a favorable IL10/IL12 compared to CTR (p &lt; 0.001). The eAECs and tdAECs displayed two different underlying regenerative mechanisms in the tendon. The eAECs positively influenced regeneration mainly through their greater ability to convey in the host tissue the shift from pro‐inflammatory to pro‐regenerative responses, leading to an ordered extracellular matrix (ECM) deposition and blood vessel remodeling. On the other hand, the transplantation of tdAECs acted mainly on the proliferative phase by impacting the density of ECM and by supporting a prompt recovery, inducing a low cellularity and angle alignment of the host cell compartment. These results support the idea that AECs lay the groundwork for production of different cell phenotypes that can orient tendon regeneration through a crosstalk with the host tissue. In particular, the obtained evidence suggests that eAECs are a practicable and efficient strategy for the treatment of acute tendinopathies, thus reinforcing the grounds to move their use towards clinical practice