Removal of aspirin from aqueous solution using phosphoric acid - modified coffee waste adsorbent

Removal of pharmaceutical waste, aspirin (ASA) in aqueous solution was investigated using activated carbon derived from coffee waste(CW). Activated carbon was prepared by using phosphoric acid as a chemical activating agent. Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the functional groups on the surface of the adsorbents. The surface area of the adsorbent was measured by BET technique. The activated carbon derived from coffee waste modified by H3PO4 was observed to have a larger surface area than AC-CW. The states of the adsorption operations are controlled by the effect of initial ASA concentration, adsorbent dose, contact time, temperature and pH adjacent on the adsorption procedure. In the batch adsorption test, the highest removal efficiency found was 98.02% in 30 minutes and 95% in 60 minutes when used H3PO4 - ACCW and AC-CW respectively. The optimum conditions for removal of aspirin from aqueous solution was found to be at 1000 mg/L of initial concentration ASA , pH 4 and at a temperature of 30°C and 0.5 g of H3PO4 - AC-CW and 0.6g AC-CW adsorbents. The experimental data for adsorption of aspirin were well fitted into Langmuir isotherm model and obeyed pseudo-second order kinetics model. The adsorption of aspirin onto H3PO4- AC-CW and AC-CW were exothermic in nature, with enthalpy change AH° = - 0.182 kJ/mol and -0.216 kJ/mol, AS0 was 0.072 J/mol -0.004 J/mol , which indicates a decrease in randomness at the adsorbent surface/aspirin solution interface, respectively. A negative Gibbs free energy AG° was obtained indicating feasibility and spontaneity of the adsorption process. For this study, the coffee waste modified by H3PO4 modified is considered as promising adsorbent and it could be employed as a low cost alternative to commercial activated in removal of aspirin in aqueous solutions

Perceptions of clinical dental students toward online education during the COVID-19 crisis: An Egyptian multicenter cross-sectional survey

Objectives: To evaluate the perceptions of clinical dental students on the role of online education in providing dental education during the COVID-19 crisis. Materials and Methods: A cross-sectional online survey was sent to four Egyptian dental schools from the 20th of January 2021 to the 3rd of February 2021. Survey questions included the demographics, uses, experiences, perceived benefits, and barriers of distance learning in dentistry during the COVID-19 pandemic. Responses were collected from the clinical dental school students. Categorical data were presented as frequencies (n) and percentages (%) and were analyzed using Fisher’s exact test. Results: Three hundred thirty-seven clinical dental students across four Egyptian dental schools responded. Most students used either Google Classroom or Microsoft Teams to access the online content. The data showed that the COVID-19 pandemic affected the academic performance of most participants (97.4%) with varying degrees. On average, students were neutral when asked to rate the online lectures, but did not find online practical education as effective (81.3%) as online theoretical teaching. The commonly described barriers to online teaching included loss of interaction with educators, inappropriateness in gaining clinical skills, and the instability of the internet connection. Conclusion: Despite the reported benefits, clinical dental students in Egypt preferred the hybrid approach in dental education as distance learning represented a prime challenge to gain adequate clinical dental skills

Survey on the Microbial Quality of Traditional Foods Sold by Street Vendors in Qatar.

During the past few years the traditional market of Qatar has become an attraction to many customers who eat from the numerous women street vendors selling Qatari traditional dishes. To gain an understanding on the safety of these street vended foods, we designed the study to test microbiological quality of 14 different Qatari foods sold in Souk Wagif, the main traditional market in Qatar. This study was conducted to mainly identify presence or absence of microbial pathogens. A total of 56 samples were purchased from 10 different street vendors and the samples were collected randomly on different days. The samples were tested for microbial contaminants at Central Food Laboratories, Doha, Qatar. The qualitative study was conducted using Real Time-PCR to screen for; Salmonella spp., Listeria monocytogenes, Escherichia coli and E. coli 0157:H7. Out of the 56 samples, only two samples “Biryani” and “Khabess” contained E. coli. However both samples tested negative for E. coli O157:H7. The microbial contamination of the Qatari traditional street vended foods was 3%. This result may be attributed to the food safety training requirement set by the regulatory authorities before issuing any license to food handlers in Qatar as well as the food inspection conducted by the Food Health Inspectors on a regular basis

Survivin and Programmed Death Ligand-1 as Possible Players in the Pathogenesis of Ulcerative Colitis: An Immunohistochemical Study

BACKGROUND: Ulcerative colitis (UC) is a relapsing chronic inflammatory disorder, with many catastrophic complications. The pathogenesis of UC is not yet well understood. Exploring the exact immunologic pathogenesis of UC may eventually offer new therapeutic options. AIM OF THE WORK: In this study, we proposed that survivin and programmed death ligand (PDL1) may have roles in the pathogenesis of UC. MATERIALS AND METHODS: The study examined the immunohistochemical expression of both markers in the colonic epithelial cells and lamina propria in 43 cases of UC and 43 cases of non-specific chronic colitis (non-inflammatory bowel disease colitis). RESULTS: The results uncovered that both survivin and PDL1 expression were significantly expressed in the colonic lamina propria cells in UC cases in comparison to colitis cases (p < 0.001). On the other hand, the expression of PDL1 was shown to be lost in the colonic mucosal cells in UC cases when compared to cases of the control group (p < 0.05). CONCLUSION: The study, therefore, concluded that both survivin and PDL1 may play an important role in the UC pathogenesis and hence may be a novel interest in new therapeutic trends

Evaluation of the Biocompatibility of a Recent Bioceramic Root Canal Sealer (BioRoot™ RCS): In-vivo Study

BACKGROUND: Recently, new calcium silicate bioceramic sealers were introduced to the market. The selection of root canal sealers should not only be based on the different physical parameters but also on local biocompatibility and tissue tolerance. AIM: This study aimed to evaluate and compare the in-vivo biocompatibility of a BioRoot RCS in parallel to MTA Fillapex and AH Plus sealers. METHODS: Polyethylene tubes containing the freshly mixed test materials were implanted in the subcutaneous tissue of 32 Wistar rats. Empty tubes served as negative controls. After 7, 14, 30, and 60 days, the animals were sacrificed, and the implants with surrounding tissues were processed for routine histological analysis. Histological sections were analyzed under light microscopy. The tissue response was determined by the inflammatory cell infiltration intensity and the fibrous capsule thickness. RESULTS: Results revealed a statistically significant decrease of the inflammation intensity by time within each group for all tested sealers and control. A well-defined thin capsule was observed for all tested sealers at 60 days. CONCLUSION: BioRoot RCS exhibited rapid recovery of inflammation similar to controls. Thus, within the limitations of this study, it can be considered a biocompatible sealer with acceptable tissue tolerance