Publications by authors named "Amina Omar"
Article Synopsis
- A study investigated how previous SARS-CoV-2 infections affect immunity after booster shots with bivalent mRNA vaccines adapted for variants BA.4/5.
- Results indicated that those with prior infections had higher levels of anti-spike antibodies after vaccination, but the increase was notably greater in uninfected individuals.
- Both groups showed better neutralizing abilities against the original strain of the virus compared to newer Omicron subvariants, but breakthrough infections were more common in the previously uninfected group who had lower neutralizing activity.
Article Synopsis
- The study examined the immunogenicity of the bivalent Omicron BA.4/5 vaccine in dialysis patients and compared it to healthy controls, focusing on vaccine-induced humoral and cellular immunity, especially considering prior infections.
- Findings showed that the vaccine significantly increased levels of IgG, neutralizing antibodies, and CD4/CD8 T-cells in both groups, with strong cross-reactivity against both the parental SARS-CoV-2 strain and Omicron subvariants.
- Notably, dialysis patients with prior infections exhibited higher levels of spike-specific CD4 T-cells and lower CTLA-4 expression compared to those without prior infections, suggesting better immune response, while vaccination was well tolerated with fewer adverse events in dialysis patients.
Article Synopsis
- The NVX-CoV2373 vaccine has been licensed, but its effectiveness compared to mRNA vaccines in generating immunity against COVID-19 variants remains unclear.
- A study involving 66 participants found that while NVX-CoV2373 induced antibodies effectively, the levels were lower than those seen with mRNA vaccines like BNT162b2 or mRNA-1273.
- The vaccine generated spike-specific CD4 T-cells in a majority of individuals, showing cross-reactivity with various variants, suggesting potential protection against severe disease despite overall lower levels of immune response.
Comparative analyses of the immunogenicity and reactogenicity of homologous and heterologous SARS-CoV-2 vaccine-regimens will inform optimized vaccine strategies. Here we analyze the humoral and cellular immune response following heterologous and homologous vaccination strategies in a convenience cohort of 331 healthy individuals. All regimens induce immunity to the vaccine antigen.
View Article and Find Full Text PDFDetecting biological structures via a rapid and facile method has become a pronounced point of research. Dopamine (DA) detection is critical for the early diagnosis of a variety of neurological diseases/disorders. A study on the real-time optical detection of DA is described here using graphene oxide (GO) functionalized with chitosan (Cs).
View Article and Find Full Text PDFEvery year, about 1 out of 9 get burnt in Egypt, with a mortality rate of 37%, and they suffer from physical disfigurement and trauma. For the treatment of second-degree burns, we aim at making a smart bandage provided with control of drug release (using chitosan nanoparticles) to enhance the healing process. This bandage is composed of natural materials; namely, cellulose acetate (CA), chitosan, and propolis (bee resin) as the loaded drug.
View Article and Find Full Text PDFHeterologous priming with the ChAdOx1 nCoV-19 vector vaccine followed by boosting with a messenger RNA vaccine (BNT162b2 or mRNA-1273) is currently recommended in Germany, although data on immunogenicity and reactogenicity are not available. In this observational study we show that, in healthy adult individuals (n = 96), the heterologous vaccine regimen induced spike-specific IgG, neutralizing antibodies and spike-specific CD4 T cells, the levels of which which were significantly higher than after homologous vector vaccine boost (n = 55) and higher or comparable in magnitude to homologous mRNA vaccine regimens (n = 62). Moreover, spike-specific CD8 T cell levels after heterologous vaccination were significantly higher than after both homologous regimens.
View Article and Find Full Text PDFThe ability of DNA to capture oligonucleotide molecules in solution is of great importance in genetics, medical diagnostics, and drug discovery. The DNA hybridization event in which the probe, which is usually a single-stranded DNA (ssDNA) covalently immobilized on a functionalized surface, recognizes the complementary target and forms a stable duplex structure that is the basis of highly specific bio recognizing devices. In this computational study, molecular modeling and Quantitative Structure Activity Relationship (QSAR) calculations were utilized at PM3 level in order to evaluate the interaction of aldehyde ssDNA on chitosan-functionalized silicon substrate and the biological activity of the proposed compounds.
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