19 research outputs found

    Influence of calcium and phosphorus release from bioactive glasses on viability and differentiation of dental pulp stem cells

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    The release of ions that can significantly contribute toward cellular response is an important characteristic of bioactive glasses (BG). Here, ionic extracts of three different compositions of BG powders in 60 mol% SiO2, x mol% CaO (x = 28, 32 and 36), x mol% P2O5 (x = 12, 8 and 4) compositional system were utilized to study their effect on the viability, differentiation and mineralization of dental pulp stem cells (DPSCs) in vitro. ICP was applied to detect the exact ionic concentrations released from different composition of BG. DPSCs treated with conditioned media from the glass with 4 mol% P2O5 (BGCM1, media containing 44.01 ± 0.6 mg/L Si, 61.72 ± 0.1 mg/L Ca and 7.57 ± 0.01 mg/L P) were more metabolically active compared to conditioned media from the glass with 8 mol% P2O5 (BGCM2, media with 47.36 ± 0.7 mg/L Si, 57.4 ± 0.1 mg/L Ca and 14.54 ± 0.2 mg/L P), at all times tested, but in all cases the process was slower than the control. Cells exposed to media conditioned by the glass with 12 mol% P2O5 (BGCM3, 40.46 ± 0.5 mg/L Si, 61. 85 ± 0.3 mg/L Ca and 28.43 ± 0.3 mg/L P) responded differently, such that cells showed to be more metabolically active than control at day 3, but then similar to or lower than control at higher time points. Differentiation of DPSCs toward osteogenic lineage in the presence of BGCM was assessed by Alizarin red staining. Cells treated with high phosphate BGCM3 displayed a higher density of red mineralized nodules than cells treated with BGCM1 and BGCM2 after 21 days of culture in non-osteogenic medium. BGCM3 was therefore chosen for gene expression studies. Osteogenic differentiation of DPSCs in the presence and/or absence of BGCM3 or osteogenic supplements were studied by RT-PCR. Overall, the results demonstrated that, in the absence of osteogenic supplements, BGCM3 group showed a significantly higher mRNA expression levels for alkaline phosphatase at day 7, osteopontin and osteonectin at days 7 and 14, and a high level of collagen I at day 14, compared to negative control group (BM−). Overall, the results obtained from BGCM3 group are beneficial for the design and manufacture of scaffolds or particulates with tailored ion release for a range of bone repair applications

    Examining queue-jumping phenomenon in heterogeneous traffic stream at signalized intersection using UAV-based data

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    © 2020, Springer-Verlag London Ltd., part of Springer Nature. This research presents an in-depth microscopic analysis of heterogeneous and undisciplined traffic at the signalized intersection. Traffic data extracted from the video recorded using an unmanned aerial vehicle (UAV) at an approach of a signalized intersection is analyzed to study the within green time dynamics of traffic flow. Various parameters of Wiedemann 74, Wiedemann 99, and lateral behavior models used in microscopic traffic simulation package, Vissim, are calibrated for the local heterogeneous traffic. This research is aimed at exploring the queue-jumping phenomenon of motorbikes at signalized intersections and its impact on the saturation flow rate, travel time, and delay. The study of within green time flow dynamics shows that the flow of traffic within green time is not uniform. Surprisingly, the results indicate that the traffic flow for the first few seconds of the green time is significantly higher than the remaining period of green time, which shows a contradiction to the fact that traffic flow for the first few seconds is lower due to accelerating vehicles. Mode-wise traffic counted per second shows that this anomaly is attributed to the presence of motorbikes in front of the queue. Consequently, the outputs of simulation results obtained from calibrated Vissim show that the simulated travel time for motorbikes is significantly lower than the field-observed travel times even though the average simulated traffic flow matches accurately with the field-observed traffic flow. The findings of this research highlight the need to incorporate the queue-jumping behavior of motorbikes in the microsimulation packages to enhance their capability to model heterogeneous and undisciplined traffic

    Post-Vasectomy Semen Analysis: Optimizing Laboratory Procedures and Test Interpretation through a Clinical Audit and Global Survey of Practices

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    Purpose: The success of vasectomy is determined by the outcome of a post-vasectomy semen analysis (PVSA). This article describes a step-by-step procedure to perform PVSA accurately, report data from patients who underwent post vasectomy semen analysis between 2015 and 2021 experience, along with results from an international online survey on clinical practice. Materials and methods: We present a detailed step-by-step protocol for performing and interpretating PVSA testing, along with recommendations for proficiency testing, competency assessment for performing PVSA, and clinical and laboratory scenarios. Moreover, we conducted an analysis of 1,114 PVSA performed at the Cleveland Clinic's Andrology Laboratory and an online survey to understand clinician responses to the PVSA results in various countries. Results: Results from our clinical experience showed that 92.1% of patients passed PVSA, with 7.9% being further tested. A total of 78 experts from 19 countries participated in the survey, and the majority reported to use time from vasectomy rather than the number of ejaculations as criterion to request PVSA. A high percentage of responders reported permitting unprotected intercourse only if PVSA samples show azoospermia while, in the presence of few non-motile sperm, the majority of responders suggested using alternative contraception, followed by another PVSA. In the presence of motile sperm, the majority of participants asked for further PVSA testing. Repeat vasectomy was mainly recommended if motile sperm were observed after multiple PVSA's. A large percentage reported to recommend a second PVSA due to the possibility of legal actions. Conclusions: Our results highlighted varying clinical practices around the globe, with controversy over the significance of non-motile sperm in the PVSA sample. Our data suggest that less stringent AUA guidelines would help improve test compliance. A large longitudinal multi-center study would clarify various doubts related to timing and interpretation of PVSA and would also help us to understand, and perhaps predict, recanalization and the potential for future failure of a vasectomy
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