Characterisation of Nicotine and Cancer-Enhancing Anions in the Common Smokeless Tobacco Afzal in Oman

Objectives: Afzal is a common smokeless tobacco product (STP) available illegally in Oman. This study aimed to assess pH and moisture levels and determine cancer-enhancing factors in a randomly selected sample of Afzal. Methods: This study was carried out at the Sultan Qaboos University in Muscat, Oman, between April and December 2013. A package of Afzal was purchased from a single provider and divided into samples. The pH and moisture content of the samples were measured according to the protocols of the Centers for Disease Control and Prevention. Gas chromatography-mass spectrometry was used to analyse nicotine levels and ionexchange chromatography (IC) was used to determine concentrations of nitrate, nitrite, chloride, fluoride, bromide, sulphate and phosphate anions. Results: The samples had an alkaline pH of 10.46 with high levels of total (48,770.00 μg per g of STP [μg/g]) and unionised (48,590.00 μg/g) nicotine. The concentration of nitrate (8,792.20 μg/g) was alarmingly high. The chloride concentration (33,170.80 μg/g) showed a surge on IC chromatography. The moisture content percentage was 52.00%. Conclusion: The moisture content percentage and chloride concentration of Afzal was consistent with those of other STPs. In contrast, nitrite, sulphate and phosphate concentrations were below reported levels of other STPs. All anion concentrations were below the maximum daily limit set by international health organisations. However, the high concentrations of nitrite, nitrate and nicotine and the elevated alkaline pH observed in the analysed Afzal samples suggest that STP users will face health risks as a result of their use

controlled inlet airflow in ventilated facades a numerical analysis

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The differential mediating roles of resilience in the relationship between meaningful living and stress among college students during the COVID-19 pandemic

The current literature, mostly Euro-American based, indicates that the presence of meaning in life (MIL) improves resilience and lowers stress. However, the differential mediating roles of resilience in the relationship between the search for and presence of MIL, and stress have not been explored. This study aimed to investigate the differential mediating roles of resilience in the relationship between the presence of and search for MIL, and stress among Omani college students amid the COVID-19 pandemic. This cross-sectional study consisted of the Brief Resilience Scale, Perceived Stress Scale 4, and Meaning in Life Questionnaire, as well as socio-demographic questions. A path analysis model was used to examine the hypothesis. A total of 970 Omani college students responded to the questionnaire. Findings indicate that searching for MIL was significantly associated with a high level of stress directly (β = 0.023; p < 0.001) and indirectly, through a negative effect on resilience (β =  0.006; p < 0.001). Conversely, the presence of MIL was significantly associated with a decreased level of stress directly (β = − 0.045; p < 0.001) and indirectly via a positive effect on resilience (β = − 0.151; p < 0.001). In keeping with the proposed hypothesis, this study contributes to the current knowledge, by extrapolating the effect of searching for MIL on resilience and stress, and culturally re-contextualizing MIL research. University counseling centers could adopt meaning-based strategies to mitigate stress by promoting meaningful living and resilience

A Major Role for Side-Chain Polyglutamine Hydrogen Bonding in Irreversible Ataxin-3 Aggregation

The protein ataxin-3 consists of an N-terminal globular Josephin domain (JD) and an unstructured C-terminal region containing a stretch of consecutive glutamines that triggers the neurodegenerative disorder spinocerebellar ataxia type 3, when it is expanded beyond a critical threshold. The disease results from misfolding and aggregation, although the pathway and structure of the aggregation intermediates are not fully understood. In order to provide insight into the mechanism of the process, we monitored the aggregation of a normal (AT3Q24) ataxin-3, an expanded (AT3Q55) ataxin-3, and the JD in isolation. We observed that all of them aggregated, although the latter did so at a much slower rate. Furthermore, the expanded AT3Q55 displayed a substantially different behavior with respect to the two other variants in that at the latest stages of the process it was the only one that did the following: i) lost its reactivity towards an anti-oligomer antibody, ii) generated SDS-insoluble aggregates, iii) gave rise to bundles of elongated fibrils, and iv) displayed two additional bands at 1604 and 1656 cm−1 in FTIR spectroscopy. Although these were previously observed in other aggregated polyglutamine proteins, no one has assigned them unambiguously, yet. By H/D exchange experiments we show for the first time that they can be ascribed to glutamine side-chain hydrogen bonding, which is therefore the hallmark of irreversibly SDS-insoluble aggregated protein. FTIR spectra also showed that main-chain intermolecular hydrogen bonding preceded that of glutamine side-chains, which suggests that the former favors the latter by reorganizing backbone geometry

Characterisation of Nicotine and Cancer-Enhancing Anions in the Common Smokeless Tobacco Afzal in Oman

Objectives: Afzal is a common smokeless tobacco product (STP) available illegally in Oman. This study aimed to assess pH and moisture levels and determine cancer-enhancing factors in a randomly selected sample of Afzal. Methods: This study was carried out at the Sultan Qaboos University in Muscat, Oman, between April and December 2013. A package of Afzal was purchased from a single provider and divided into samples. The pH and moisture content of the samples were measured according to the protocols of the Centers for Disease Control and Prevention. Gas chromatography-mass spectrometry was used to analyse nicotine levels and ionexchange chromatography (IC) was used to determine concentrations of nitrate, nitrite, chloride, fluoride, bromide, sulphate and phosphate anions. Results: The samples had an alkaline pH of 10.46 with high levels of total (48,770.00 μg per g of STP [μg/g]) and unionised (48,590.00 μg/g) nicotine. The concentration of nitrate (8,792.20 μg/g) was alarmingly high. The chloride concentration (33,170.80 μg/g) showed a surge on IC chromatography. The moisture content percentage was 52.00%. Conclusion: The moisture content percentage and chloride concentration of Afzal was consistent with those of other STPs. In contrast, nitrite, sulphate and phosphate concentrations were below reported levels of other STPs. All anion concentrations were below the maximum daily limit set by international health organisations. However, the high concentrations of nitrite, nitrate and nicotine and the elevated alkaline pH observed in the analysed Afzal samples suggest that STP users will face health risks as a result of their use

Individual and summed effects of high-risk genetic polymorphisms on recurrent cardiovascular events following ischemic heart disease.

AIMS: High-risk single nucleotide polymorphisms (SNPs) have been recently identified as risk factors for ischemic heart disease in large epidemiological and genome-wide association studies. However, their influence on prognosis remains uncertain. The aim of the study was to investigate the impact of previously identified SNPs and their joint effects in a genetic score (GS) on Major Adverse Cardiac Events (MACEs). METHODS AND RESULTS: High-throughput genotyping for 48 high-risk SNPs was performed in 498 patients (432 males; 57.4 ± 8.3 years) who were followed-up for 6.9 ± 3.4 years. First MACE-coronary-related death, nonfatal myocardial infarction, or myocardial revascularization- was the endpoint taken into consideration. A GS was obtained by summing the number of significant high-risk alleles associated to MACEs. One-hundred and nineteen patients (24%) had a MACE. The hazard ratio (HR) for SNPs with a significant difference in cumulative survival were: APOC3 -482C > T (HR = 1.7, 95% CI 1.01-3.0), MTHFR (HR = 1.5, 95% CI 1.02-2.2), NADHPH oxidase- p22-PHOX C242T (HR = 1.9, 95% CI 1.2-2.8), PON-2 (HR = 0.2, 95% CI 0.1-0.8), and SELP (HR = 0.6, 95% CI 0.4-0.8). The resulting GS predicted a 25% risk for MACEs per risk allele (HR = 1.25, 95% CI 1.1-1.4, p = 0.001). The highest HR for MACEs was found in patients in the top tertile (HR = 3.0, 95% CI 1.4-6.7, p = 0.0005) of the GS compared with those in the bottom tertile. CONCLUSION: Our findings show that high-risk SNPs may be used to create a useful GS that predicts MACEs in a secondary prevention setting, which in turn allows a better risk stratification