RESUMO
BACKGROUND: During October 2020, Delta variant was detected for the first time in India and rampantly spread across the globe. It also led to second wave of pandemic in India which affected millions of people. However, there is limited information pertaining to the SARS-CoV-2 strain infecting the children in India. METHODS: Here, we assessed the SARS-CoV-2 lineages circulating in the pediatric population of India during the second wave of the pandemic. Clinical and demographic details linked with the nasopharyngeal/oropharyngeal swabs (NPS/OPS) collected from SARS-CoV-2 cases (n = 583) aged 0-18 year and tested positive by real-time RT-PCR were retrieved from March to June 2021. RESULTS: Symptoms were reported among 37.2% of patients and 14.8% reported to be hospitalized. The E gene CT value had significant statistical difference at the point of sample collection when compared to that observed in the sequencing laboratory. Out of these 512 sequences 372 were VOCs, 51 were VOIs. Most common lineages observed were Delta, followed by Kappa, Alpha and B.1.36, seen in 65.82%, 9.96%, 6.83% and 4.68%, respectively in the study population. CONCLUSION: Overall, it was observed that Delta strain was the leading cause of SARS-CoV-2 infection in Indian children during the second wave of the pandemic. We emphasize on the need of continuous genomic surveillance in SARS-CoV-2 infection even amongst children.
Assuntos
COVID-19 , Humanos , Criança , COVID-19/epidemiologia , SARS-CoV-2/genética , Índia/epidemiologia , Povo AsiáticoRESUMO
INTRODUCTION: Glass ionomer cements (GICs) are commonly used for cementation of indirect restorations. However, one of their main drawbacks is their inferior mechanical properties. AIM: Compositional modification of conventional glass ionomer luting cements by incorporating two types of all-ceramic powders in varying concentrations and evaluation of their film thickness, setting time, and strength. Material & Methods. Experimental GICs were prepared by adding different concentrations of two all-ceramic powders (5%, 10, and 15% by weight) to the powder of the glass ionomer luting cements, and their setting time, film thickness, and compressive strength were determined. The Differential Scanning Calorimetry analysis was done to evaluate the kinetics of the setting reaction of the samples. The average particle size of the all-ceramic and glass ionomer powders was determined with the help of a particle size analyzer. RESULTS: A significant increase in strength was observed in experimental GICs containing 10% all-ceramic powders. The experimental GICs with 5% all-ceramic powders showed no improvement in strength, whereas those containing 15% all-ceramic powders exhibited a marked decrease in strength. Setting time of all experimental GICs progressively increased with increasing concentration of all-ceramic powders. Film thickness of all experimental GICs was much higher than the recommended value for clinical application. CONCLUSION: 10% concentration of the two all-ceramic powders can be regarded as the optimal concentration for enhancing the glass ionomer luting cements' strength. There was a significant increase in the setting time at this concentration, but it was within the limit specified by ISO 9917-1:2007 specifications for powder/liquid acid-base dental cements. Reducing the particle size of the all-ceramic powders may help in decreasing the film thickness, which is an essential parameter for the clinical performance of any luting cement.