Evaluation of nanoparticles with 5-fluorouracil and chloroquine on Acanthamoeba castellanii activity.

Acanthamoeba is opportunistic pathogens that cause vision-threatening Acanthamoeba keratitis (AK). Previous studies proposed the use of chloroquine (CQ) and 5-fluorouracil (5FU) as anti-Acanthamoeba agents. The objective of this study was to determine the benefit of using 5FU and CQ nanoparticles (NP) formulations against A. castellanii that belonging to the T4 genotype and evaluate their anti-Acanthamoebic characteristic. Triplicate batches of 5FU nanoparticles (5FU-NP) were synthesized by using a modified nanoprecipitation method, while CQ nanoparticles (CQ-NP) synthesized using a modified double emulsion method. The synthesized nanoparticles were subjected to biological assays to investigate their amoebicidal, amoebistatic, anti-encystation, and anti-excystation effects against A. castellanii, as well as cell cytotoxicity. Cytotoxicity assays were performed using human keratinocyte cells (HaCaT) to determine the effect of CQ and 5FU nanoformulations on host cells. 5FU-NP with a concentration of 60 µM showed significant inhibition to amoeba binding into human cell lines and remarkable prevention mainly during the encystation stage. Moreover, 5FU-NP resulted in less cytotoxicity and pathogenicity when compared with the free 5FU. On the other hand, CQ and CQ-NP, at the same concentration, showed poor inhibition to amoeba binding into human cells and insignificant prevention to encystation stage. Moderate human cells damage was resulted following their treatment with CQ and CQ-NP. In conclusion, 5FU may have the potential as an antiamoebic agent against Acanthamoeba spp. preferably as a nanoformulation to enhance its activity and reduce its cytoxicity.

Side effects and perceptions following Sinopharm COVID-19 vaccination.

OBJECTIVES: Vaccines are one of the best interventions developed for eradicating COVID-19. This study aimed to provide evidence on Sinopharm COVID-19 vaccine side effects. METHODS: A cross-sectional survey study was conducted between January and April 2021 to collect data on the effects of the COVID-19 vaccine among individuals in the United Arab Emirates. Demographic data, vaccination and the response of people unwilling to take the COVID-19 vaccine were reported. RESULTS: Side effects post first vaccine dose of normal injection site pain, fatigue and headache were more common in participants aged ≤49 years versus >49 years, while pain at the vaccination site, fatigue, lethargy, headache and tenderness were the most common side effects post second dose in both groups. All side effects for both doses were more prevalent among participants aged ≤49 years. Side effects were more common in females compared with males for both doses. The most common reason for being unwilling to take the COVID-19 vaccine was that vaccines are not effective. CONCLUSION: Post-vaccination side effects for the first and second doses were mild and predictable, and there were no hospitalization cases; this data will help reduce vaccine hesitancy.

Vitamin D Deficiency and Insufficiency Among University Students: Prevalence, Risk Factors, and the Association Between Vitamin D Deficiency and Episodes of Respiratory Tract Infections.

BACKGROUND: Vitamin D deficiency (VDD) and insufficiency (VDI) is a public health problem worldwide. Low blood levels of vitamin D have been associated with many illnesses, including respiratory tract infections (RTIs). This study aims to evaluate the prevalence of VDD and VDI among university students, assess the correlation with demographic and anthropometric factors, and determine the effect of VDD on the respiratory tract infection (RTI) incidence. METHODS: A cross-sectional and prospective design was used. Our sample consisted of 287 students aged 18-24 years from the University of Sharjah-UAE. Participants were tested for serum 25(hydroxyvitamin)D levels, Body mass index (BMI) was calculated, and the survey was completed. The association between VDD, VDI with the participant's characteristics, and the incidents of RTIs were examined. RESULTS: VDD and VDI were highly prevalent among 85% of the students. The median serum 25(OH) D level was 15.8 ng/dl (19.5±11.6). The mean BMI was (24.32±6.3) kg/m. The results showed a significant positive correlation between VDI and VDD with gender and students who were previously diagnosed with VDD (P < 0.05); however, they were not statistically significant (P < 0.05) with other factors. The tonsillitis incidents were significantly associated with VDD (P = 0.027), while no significant correlation with other incidences of RTIs was found. CONCLUSION: VDD and VDI represent a significant problem across the university students specifically with the female gender. VDD is associated with tonsillitis infection incidence. Both the health and higher education authorities' attention is needed, exploring the causes of VDD and VDI, regular 25(OH)D serum level examination, and educational programs on VDD risks are required.