Comparison of immune activation of the COVID vaccines: ChAdOx1, BNT162b2, mRNA-1273, BBIBP-CorV, and Gam-COVID-Vac from serological human samples in Hungary showed higher protection after mRNA-based immunization.

OBJECTIVE: To gain insight into the different protective mechanisms of approved vaccines, this study focuses on the comparison of humoral and cellular immune responses of five widely used vaccines including ChAdOx1 (AZD1222, AstraZeneca), BNT162b2 (Pfizer), mRNA-1273 (Moderna), BBIBP-CorV (Sinopharm), and Gam-COVID-Vac (Sputnik V). MATERIALS AND METHODS: Isolated plasma from 95 volunteers' blood samples was used to measure anti-SARS-CoV-2 humoral and cellular immune responses. Positive controls were recovered patients from COVID-19 (unvaccinated). Specific quantification kits for anti-nucleocapsid IgG, anti-Spike protein IgG, neutralizing antibodies as well as specific SARS-CoV-2 antigens for T-cell activation were used and Spearman correlation and matrix analyses were performed to compare overall immune responses. RESULTS: Nucleocapsid antibodies were significantly higher for the BBIBP-CorV and convalescent group when compared to other vaccines. In contrast, subjects vaccinated with BNT162b2 and mRNA-1273 presented significantly higher anti-spike IgG. In fact, 9.1% of convalescent, 4.5% of Gam-COVID-Vac, 28.6% of ChAdOx1, and 12.5% of BBIBP-CorV volunteers did not generate anti-spike IgG. Similarly, a positive correlation was observed after the neutralization assay. T-cell activation studies showed that mRNA-based vaccines induced a T-cell driven immune response in all cases, while 55% of convalescents,  8% of BNT162b1,  12,5% of mRNA-1273, 9% of Gam-COVID-Vac,  57% of ChAdOx1,  and  56% of BBIBP-CorV subjects presented no cellular response. Further correlation matrix analyses indicated that anti-spike IgG and neutralizing antibodies production, and T-cell activation follow the same trend after immunization. CONCLUSIONS: RNA-based vaccines induced the most robust adaptive immune activation against SARS-CoV-2 by promoting a significantly higher T-cell response, anti-spike IgG and neutralization levels. Vector-based vaccines protected against the virus at a comparable level to convalescent patients.

The cardioprotective potential of hydrogen sulfide in myocardial ischemia/reperfusion injury (review).

Myocardial infarction is responsible for the majority of cardiovascular mortality and the pathogenesis of myocardial damage during and after the infarction involves reactive oxygen species. Serious efforts are under way to modulate the developing ischemia/reperfusion injury and recently the use of hydrogen sulfide (H2S) emerged as a new possibility. H2S has been best known for decades as a pungent toxic gas in contaminated environmental atmosphere, but it has now been recognized as a novel gasotransmitter in the central nervous and cardiovascular systems, similarly to nitric oxide (NO) and carbon monoxide (CO). This finding prompted the investigation of the potential of H2S as a cardioprotective agent and various in vitro and in vivo results demonstrate that H2S may be of value in cytoprotection during the evolution of myocardial infarction. Although several questions remain to be elucidated about the properties of this new gasotransmitter, increased H2S levels may have therapeutic potential in clinical settings in which ischemia/reperfusion injury is encountered. This review article overviews the current understanding of the effects of this exciting molecule in the setting of myocardial ischemia/reperfusion.

Spectrofluorimetric determination of 1,3,5-trinitro-1,3,5-triazacyclohexane (hexogen, RDX) as a nitramine type explosive.

RDX is one of the most important military explosives. It is a component of some plastic explosives which are frequently used in terrorist attacks. Two fluorimetric methods have been described for the quantitative determination of RDX which are based on the detection of nitrite ions. After a basic decomposition of RDX the nitrite ion can be detected by reaction with 4-aminofluorescein and by reactions forming a lumogallion-gallium(III) complex. These fluorimetric methods have been compared to a photometric reaction (Griess reaction) for determination of nitrite ions. It has been found that the fluorimetric methods have a higher sensitivity than the photometric method and they have been used in a wider concentration range.

Spectrofluorimetric determination of diethazine and promethazine in pharmaceutical preparations.

A simple, sensitive and accurate spectrofluorimetric method is described for the quantitative determination of diethazine and promethazine either in the pure form or in its pharmaceuticals. The method is based on the formation of red fluorescent product of these drugs with Au(III). A linear calibration graph is obtained over the range 0.05-100 p.p.m. of diethazine and promethazine.