Exogenous hydrogen sulphide alleviates copper stress impacts in Artemisia annua L.: Growth, antioxidant metabolism, glandular trichome development and artemisinin biosynthesis.

A supply of plant micronutrients (some of which are metals) is necessary to regulate many plant processes; their excess, however, can have detrimental consequences and can hamper plant growth, physiology and metabolism. Artemisia annua is an important crop plant used in the treatment of malaria. In this investigation, the physio-biochemical mechanisms involved in exogenous hydrogen sulphide-mediated (H2 S) alleviation of copper (Cu) stress in A. annua were assessed.. Two different levels of Cu (20, 40 mg·kg-1 ), one H2 S treatment (200 µm) and their combinations were introduced while one set of plants was retained as control. Results showed that the presence of excess Cu in the soil reduced growth and biomass, photosynthetic parameters, chlorophyll content and fluorescence, gas exchange parameters and induced antioxidant enzyme activity. Copper stress enhanced the production of thiobarbituric acid reactive substances (TBARS) and increased Cu content in both roots and shoots of affected plants. Exogenous application of H2 S restored the physio-biochemical characteristics of Cu-treated A. annua plants by reducing lipid peroxidation and enhancing the activity of antioxidant enzymes in Cu-stressed plants as compared with the controls. Hydrogen sulphide also reduced the Cu content in different plant parts, increased photosynthetic efficiency, trichome density, average area of trichomes and artemisinin content. Therefore, our results provide a comprehensive assessment of the defensive role of H2 S in Cu-stressed A. annua.

Hydrogen sulphide infiltration downregulates oxidative metabolism and extends postharvest life of banana.

Hydrogen sulphide (H2 S) has emerged as a potential regulator of plant defence against different abiotic stresses. As a climacteric fruit, banana undergoes oxidative stresses shortly after harvest, resulting in faster ripening and senescence. This work examines the effects of vacuum infiltrated H2 S on ripening inhibition of banana. Banana fruits were vacuum infiltrated with 1 mm H2 S. Effects on oxidative stress markers, physiological changes, bioactive compounds and antioxidant potentials were examined during storage at 25 °C and 75-80% RH. Results indicate that treated fruits were less affected by oxidative stress, as evident by lower accumulation of ROS (superoxide and peroxide ions), elevated phenols content and antioxidant capacity. The ripening inhibitory effects of H2 S delayed chlorophyll loss and reduced ethylene and CO2 production. H2 S infiltration also reduced MDA accumulation and electrolytic leakage, resulting in longer shelf life. Vacuum infiltration with H2 S had a protective effect on postharvest banana through overcoming the deleterious effect of ROS and strengthening antioxidant potential. Thus, this method could be promising for enhanced preservation of banana during storage.

Prevention of postpartum hemorrhage at home birth in Afghanistan.

OBJECTIVE: To test the safety, acceptability, feasibility, and effectiveness of community-based education and distribution of misoprostol for prevention of postpartum hemorrhage at home birth in Afghanistan. METHODS: A nonrandomized experimental control design in rural Afghanistan. RESULTS: A total of 3187 women participated: 2039 in the intervention group and 1148 in the control group. Of the 1421 women in the intervention group who took misoprostol, 100% correctly took it after birth, including 20 women with twin pregnancies. Adverse effect rates were unexpectedly lower in the intervention group than in the comparison group. Among women in the intervention group, 92% said they would use misoprostol in their next pregnancy. In the intervention area where community-based distribution of misoprostol was introduced, near-universal uterotonic coverage (92%) was achieved compared with 25% coverage in the control areas. CONCLUSION: In Afghanistan, community-based education and distribution of misoprostol is safe, acceptable, feasible, and effective. This strategy should be considered for other countries where access to skilled attendance is limited.