Effect of Daily Chewing Soft Buds and Leaves of Catha edulis (Khat) on the Antioxidant Defense System and Oxidative Stress Markers in Blood

Catha edulis (Khat) is one of the major economic, social and health problems in Yemen. This paper aimed to study the effect of Khat on the oxidative status of Khat chewers by measuring the levels of enzymatic and non-enzymatic antioxidant as well as lipid peroxidation. The results exhibited significant reduction in erythrocytes superoxide dismutase (SOD, EC: 1.15.1.1), and catalase (CAT, EC: 1.11.1.6) in Khat chewers, in addition to elevation of serum glutathione-S-transferase (GST, EC: 2.5.1.18). Furthermore, non-enzymatic antioxidants glutathione (GSH) and vitamin C were significantly reduced (p < 0.001; p < 0.015), whereas malondialdehyde (MDA) was significantly elevated (p < 0.001). The depletion of GSH and vitamin C along with MDA elevation in Khat chewers compared with control reflects the obvious oxidative status, a result of enormous reactive oxygen species (ROS) formation, leading to membrane damage. ROS possibly induced by active components of Khat or by pesticides added to the Khat tree. In addition, the reduction of SOD and CAT is indicative to cellular proteins damage which occurred by ROS. As well, the elevation of GST may due to a leakage of cellular GST to blood stream; this implies that GST active site was not affected. This study concludes that daily chewing Khat for long period certainly induce ROS production, leading to oxidative toxicity. Both enzymatic and non-enzymatic antioxidants are involved in the protection against this toxicity. People who habitually chew Khat for long term will be susceptible to the oxidative toxicity; therefore, they recommended giving up of Khat chewing

ABA biosynthesis defective mutants reduce some free amino acids accumulation under drought stress in tomato leaves in comparison with Arabidopsis plants tissues

<p>drought stress</p

Identification and Characterization of α-Amylase from Yemeni Bean (Dolichos Lablab L.) Seeds : Jordan Journal of Chemistry

<p>Describe the partial purification and identification of Alpha amylase from loacal yemeni beans</p

Potential health effects of daily k h at leaves chewing: study on the biochemical blood constituents changes among adult S in Sana'A City, Yemen

The khat plant (Catha edulis) leaves is grown and consumed daily in Yemen as a natural stimulant by chewing the young buds and tender leaves that contain the stimulant “Cathinone” for the mild stimulant effect. Cathinone is believed to be the main active ingredient in fresh khat leaves. In Yemen this habit has a deep-rooted socio-cultural tradition in which consumers spend part of their time chewing khat (ranging between 6-8 hours per day). The effect of this habit on blood constituent has not been adequately studied in human. There is an extensive literature on khat which estimated the effectiveness and specificity for these substances on kidney and liver function test in animals than humans. The present study was undertaken to investigate the biochemical changes associated with chewing Khat

INFLUENCE OF KHAT ON THE LEVEL OF CLINICAL BIOMARKERS IN BLOOD OF KHAT CHEWERS

<p>Describe the effect of khat chewing on the biochemical and clinical markers in blood </p

Effect of Daily Chewing Soft Buds and Leaves of Catha edulis (Khat) on the Antioxidant Defense System and Oxidative Stress Markers in Blood

<p>Describe the effect of khat chewing on the level of oxidative biomarkers on blood</p

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population