Evaluating the Role of BglI rs739837 and TaqI rs731236 Polymorphisms in Vitamin D Receptor with SARS-CoV-2 Variants Mortality Rate.

A lack of vitamin D is a potential risk factor for coronavirus disease (COVID-19). Variants in the Vitamin D Receptor (VDR) gene, such as BglI rs739837 and TaqI rs731236, are associated with various viral infection progressions. This study aimed to evaluate the relationship between the BglI rs739837 and TaqI rs731236 polymorphisms and the mortality rate of COVID-19 based on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. The genotyping of BglI rs739837 and TaqI rs731236 genotypes was analyzed using the polymerase chain reaction-restriction fragment length polymorphism in 1734 improved and 1450 deceased patients positive for SARS-CoV-2. In this study, the rate of COVID-19 mortality was correlated with TaqI rs731236 TC and CC in the α variant and with TaqI rs731236 CC in the Delta variant, whereas no relationship was found in the Omicron BA.5 variant. In addition, the rate of COVID-19 mortality was associated with BglI rs739837 GT and TT in the Omicron BA.5 variant, while there was no association between BglI rs739837 and COVID-19 mortality in the α and Delta variants. The TG haplotype was more common in all SARS-CoV-2 variants, while the CT haplotype was associated with COVID-19 mortality in the Delta and Omicron BA.5 variants. In conclusion, this study indicated that the impacts of BglI rs739837 and TaqI rs731236 polymorphisms were related to SARS-CoV-2 variants. However, further research is still needed to approve our findings.

Reactivity of aminophenols in forming nitrogen-containing brown carbon from iron-catalyzed reactions.

Nitrogen-containing organic carbon (NOC) in atmospheric particles is an important class of brown carbon (BrC). Redox active NOC like aminophenols received little attention in their ability to form BrC. Here we show that iron can catalyze dark oxidative oligomerization of o- and p-aminophenols under simulated aerosol and cloud conditions (pH 1-7, and ionic strength 0.01-1 M). Homogeneous aqueous phase reactions were conducted using soluble Fe(III), where particle growth/agglomeration were monitored using dynamic light scattering. Mass yield experiments of insoluble soot-like dark brown to black particles were as high as 40%. Hygroscopicity growth factors (κ) of these insoluble products under sub- and super-saturated conditions ranged from 0.4-0.6, higher than that of levoglucosan, a prominent proxy for biomass burning organic aerosol (BBOA). Soluble products analyzed using chromatography and mass spectrometry revealed the formation of ring coupling products of o- and p-aminophenols and their primary oxidation products. Heterogeneous reactions of aminophenol were also conducted using Arizona Test Dust (AZTD) under simulated aging conditions, and showed clear changes to optical properties, morphology, mixing state, and chemical composition. These results highlight the important role of iron redox chemistry in BrC formation under atmospherically relevant conditions.

Rigorous quantification of statistical significance of the COVID-19 lockdown effect on air quality: The case from ground-based measurements in Ontario, Canada.

Preliminary analyses of satellite measurements from around the world showed drops in nitrogen dioxide (NO2) coinciding with lockdowns due to the COVID-19 pandemic. Several studies found that these drops correlated with local decreases in transportation and/or industry. None of these studies, however, has rigorously quantified the statistical significance of these drops relative to natural meteorological variability and other factors that influence pollutant levels during similar time periods in previous years. Here, we develop a novel statistical protocol that accounts for seasonal variability, transboundary influences, and new factors such as COVID-19 restrictions in explaining trends in several pollutant levels at 16 ground-based measurement sites in Southern Ontario, Canada. We find statistically significant and temporary drops in NO2 (11 out 16 sites) and CO (all 4 sites) in April-December 2020, with pollutant levels 20% lower than in the previous three years. Fewer sites (2-3 out of 16) experienced statistically significant drops in O3 and PM2.5. The statistical significance testing framework developed here is the first of its kind applied to air quality data. It highlights the benefit of a rigorous assessment of statistical significance, should analyses of pollutant levels post COVID-19 lockdowns be used to inform policy decisions.

Dark Iron-Catalyzed Reactions in Acidic and Viscous Aerosol Systems Efficiently Form Secondary Brown Carbon.

Iron-driven secondary brown carbon formation reactions from water-soluble organics in cloud droplets and aerosols create insoluble and soluble products of emerging atmospheric importance. This work shows, for the first time, results on dark iron-catalyzed polymerization of catechol forming insoluble black polycatechol particles and colored water-soluble oligomers under conditions characteristic of viscous multicomponent aerosol systems with relatively high ionic strength (I = 1-12 m) and acidic pH (∼2). These systems contain ammonium sulfate (AS)/nitrate (AN) and C3-C5 dicarboxylic acids, namely, malonic, malic, succinic, and glutaric acids. Using dynamic light scattering (DLS) and ultra high pressure liquid chromatography-mass spectrometry (UHPLC-MS), we show results on the rate of particle growth/agglomeration and identity of soluble oligomeric reaction products. We found that increasing I above 1 m and adding diacids with oxygen-to-carbon molar ratio (O:C > 1) significantly reduced the rate of polycatechol formation/aggregation by a factor of 1.3 ± 0.4 in AS solution in the first 60 min of reaction time. Using AN, rates were too slow to be quantified using DLS, but particles formed after 24 h reaction time. These results were explained by the relative concentration and affinity of ligands to Fe(III). We also report detectable amounts of soluble and colored oligomers in reactions with a slow rate of polycatechol formation, including organonitrogen compounds. These results highlight that brown carbon formation from iron chemistry is efficient under a wide range of aerosol physical states and chemical composition.

A remote sensing study of spatiotemporal variations in drought conditions in northern Asir, Saudi Arabia.

Changes in vegetation land cover are influenced by, and therefore an indicator of, climatic conditions. The aim of this study is to investigate the relationship between vegetation cover changes and drought events in a small-scale area. Six Landsat images during 1987-2019 were used to extract information about the vegetation land cover changes using the normalized difference vegetation index (NDVI) and the fractional vegetation cover (FVC) in Balqarn Governorate in the northern mountains of Asir, Saudi Arabia. Two climatic parameters, temperature and precipitation, were used as time series for the same period and were decomposed to investigate the seasonal and trend changes for each parameter. The two parameters were also used to calculate the standardized precipitation evapotranspiration index (SPEI) to conduct an in-depth analysis of the drought events influencing vegetation cover. The results showed that the state of the vegetation coverage of the study area remained at a medium level with an average NDVI value, but the FVC values showed evidence of dynamic variability associated with drought and moisture events. The SPEI showed that the study area has been undergoing a long-duration drought event since 2004, ranging from light to severe drought, which was consistent with the time series decomposition results. This investigation has revealed that drought drives changes in vegetation cover and is expressed on small geographic scales as changes in the vegetation cover structure. The framework described here is simple and can be used to evaluate and manage drought risks.

Molecular assessment of some cardiovascular genetic risk factors among Iraqi patients with ischemic heart diseases.

OBJECTIVE: The underlying molecular basis of ischemic heart diseases (IHDs) has not yet been studied among Iraqi people. This study determined the frequency and types of some cardiovascular genetic risk factors among Iraqi patients with IHDs. METHODS: This is a cross-sectional study recruiting 56 patients with acute IHD during a 2-month period excluding patients >50 years and patients with documented hyperlipidemia. Their ages ranged between 18 and 50 years; males were 54 and females were only 2. Peripheral blood samples were aspirated from all patients for troponin I and DNA testing. Molecular analysis to detect 12 common cardiovascular genetic risk factors using CVD StripAssay® (ViennaLab Diagnostics GmbH, Austria) was performed. RESULTS: The genotype frequencies of 12 genetic mutations/polymorphisms were as follows: MTHFR A1298C and C677T were the highest reported mutations (62.5% and 50%, respectively), followed by ß-fibrinogen gene mutation, homozygous angiotensin-converting enzyme D/D, heterozygous human platelet antigen-1(a/b) polymorphisms, plasminogen activator inhibitor-1 4G/4G, homozygous E4 allele of apolipoprotein E gene, Leu allele of Factor XIII V34L variant, heterozygous FV R2, Factor V Leiden mutation, prothrombin G20210A mutation, respectively. Genetic risk scores were calculated and a number ranging from 0 to 8 were given to each patient. None (0%) had a risk score >6 or <2; 22 (39.3%) patients had a risk score of 4 and >60% of cases had a risk score of 4 or more. CONCLUSION: The obtained results constitute a reference guide where future studies on normal people and older IHD patients can rely on to determine whether these can be used for pre-clinical risk assessment.