ABSTRACT
@#Introduction: Ozone (O3 ) is a significant component of photochemical smog as a typical secondary which is formed via nitrogen oxide photochemical interactions with volatile organic compounds (VOCs). This research discerns the complex influence of meteorological parameters and air pollutants influencing O3 concentrations. Methods: Data were acquired from 1 January 2018 until 31 December 2020 that including ozone (O3 ), nitrogen oxide (NOx), nitric oxide (NO), sulphur dioxide (SO2 ), nitrogen dioxide (NO2 ), carbon monoxide (CO), particulate matter (PM10, PM2.5), wind speed, solar radiation, temperature, and relative humidity (RH). Data were analysed using descriptive statistics in terms of line graphs. Results: The results demonstrate that the O3 concentration peaked around 14:00 hours and dropped at night (20:00 hours) owing to the lack of sunshine and redox processes. Conclusion: In conclusion, ozone precursors played an important role in ozone formation and the findings of this research are valuable for policymakers and other interested parties
ABSTRACT
Background: Drug resistant tuberculosis (DR-TB) remains a public health issue that is of major concern on a global scale. The characterisation of clinical isolates may provide key information regarding the underlying mechanisms of drug resistance, and helps to augment therapeutic options. This study aims to evaluate the frequency of gene mutations associated with Rifampicin (RIF) and Isoniazid (INH) resistance among nine clinical isolates. Methods: A total of nine drug resistant Mycobacterium tuberculosis clinical isolates were screened for genetic mutations in rpoB and katG using polymerase chain reaction (PCR) amplification and DNA sequencing. Genotypic analysis was performed to detect the mutations in the sequence of the target genes. Results: Our findings reveal that 80% of the isolates possess mutations at codon 119 (His119Tyr) and 135 (Arg135Trp and Ser135Leu) within the rpoB gene; and 70% possess mutations in the katG gene at codon 238 with amino acid change (Leu238Arg). Conclusion: Findings from this study provide an overview of the current situation of RIF and INH resistance in a hospital Universiti Sains Malaysia (HUSM) located in Kelantan, Malaysia, which could facilitate molecular-based detection methods of drug-resistant strains. Further information regarding the molecular mechanisms involved in resistance in RR-/MDR-TB should be addressed in the near future.