Selected heavy metals in some vegetables produced through wastewater irrigation and their toxicological implications in eastern Ethiopia

Vegetables widely consumed in some areas of eastern Ethiopia such as cabbage (Brassica oleraceae var. capitata L.), potato (Solanum tuberosum L.), and khat (Catha edulis Forsk.) are cultivated through irrigation with wastewater. The purpose of this study was to analyse the contents of selected toxic heavy metal (Cr, Co, Cd and Pb) of the vegetables, the effluents used to irrigate the crops, and the soils on which the crops were grown, using flame atomic absorption spectrometry (FAAS). The optimized wet digestion procedure was employed to solubilise the metals from the samples. The validation was performed by spiking the samples with a standard solution of each metal having a known concentration and the percentage recovery values in the range of 91.0–98.3% for soil, 92.0–102% for effluent, and 89.0–101% for vegetable samples. The following concentrations (mg kg-1) of the metals were found in the edible parts of the cabbage, potato, and khat plants, respectively: Cr [less than method detection limit (<MDL)- 17.13], (11.96-14.21), and (9.04-15.54); Co (5.72-9.72), (5.15-8.72), and (<MDL-8.87); Cd (1.15-2.46), (1.22-1.46), and (0.38-3.22); Pb (5.48-11.95), (5.43-7.78), and (4.49-11). The concentrations in the effluent samples (mg kg-1) ranged from 0.17-0.26, 0.57-1.02, 0.04-0.08, and 0.82-2.52 for Cr, Co, Cd, and Pb, respectively. Similarly, concentrations (mg kg-1) of the metals in the soil samples were in the ranges of 25.71-41.45, 17.69-23.59, 0.79-2.56, and 26.04-47.29 for Cr, Co, and Cd, and Pb, respectively. The study revealed that the concentrations of all metals in the vegetables, except Co, were found to be above the safe limits set by different international organizations for consumption, posing a serious health hazard to humans. Therefore, regular monitoring of effluents, soils, and vegetables are essential to prevent excessive build-up of the toxic heavy metals in food. Thus, the health risk and the extent of heavy metal contamination can be reduced.Keywords: Vegetables, wastewater, safe limits, irrigatio

Inhaled Corticosteroids and the Risk of Lung Cancer in Chronic Obstructive Pulmonary Disease Patients: A Systematic Review and Meta-Analysis

BACKGROUND: The global prevalence of chronic obstructive pulmonary disease (COPD) is increasing, and the risk of lung cancer in these patients is high. The use of inhaled corticosteroids (ICSs) in COPD patients could help to decrease potential lung cancer risk. We planned to conduct this systematic review and meta-analysis to determine the role of ICS in the risk of lung cancer among COPD patients. METHODS: A comprehensive search of PubMed, Science Direct, Google Scholar, and Cochrane library and a manual search of the list of references were conducted. Studies with cohort, case-control, and randomized clinical trial designs for any ICS use reporting the incidence/hazard ratio (HR) of lung cancer were included. The random-effects model was used to pool hazard ratios. Subgroup analysis and metaregression analysis were employed. Funnel plot and Egger regression test were used to assess publication bias. RESULTS: Combining the results of 14 observations, the pooled HR for cancer risk reduction was 0.69 (95% CI 0.59-0.79), p value ≤ 0.001. The use of ICS in COPD patients showed a 31% reduction in the risk of lung cancer. Subgroup meta-analysis showed a significant reduction in the risk of lung cancer as well. CONCLUSION: The use of ICS in COPD patients reduces the risk of lung cancer. The risk reduction was independent of smoking status and latency period. Future studies should focus on the optimum dose and controlling confounders like asthma

Optimization of total protein and activity assays for the detection of MMP-12 in induced human sputum

<p>Abstract</p> <p>Background</p> <p>Proteolysis of matrix components, in particular elastin, is a major contributing factor to the development of lung diseases such as emphysema and chronic obstructive pulmonary disease (COPD). MMP-12 (macrophage elastase) is a protease known to be involved in the progression of lung disease. The relatively low abundance of MMP-12 has precluded the development of quantitative assays that can accurately measure MMP-12 protein levels and activity across cohorts of healthy and diseased individuals.</p> <p>Methods</p> <p>Commercial antibodies were screened for performance in sandwich ELISA and capture FRET activity assay formats. Precision, accuracy, sensitivity, dilution linearity, and spike recovery were evaluated using sputum samples.</p> <p>Results</p> <p>Total protein and capture FRET activity assays were developed that were sensitive enough to detect MMP-12 in 37 of 38 donor sputum samples. A comparison of results between the two assays shows that a majority of sputum MMP-12 is in the active form. No differences were seen between normal, asthmatic, and COPD donors.</p> <p>Conclusion</p> <p>Sensitive and quantitative assays for both MMP-12 activity and total protein in human induced sputum have been developed. These assays can be used to evaluate MMP-12 as a biomarker for lung disease, and to monitor efficacy of potential therapeutic compounds.</p

Sodium channel slow inactivation interferes with open channel block

Mutations in the voltage-gated sodium channel Nav1.7 are linked to inherited pain syndromes such as erythromelalgia (IEM) and paroxysmal extreme pain disorder (PEPD). PEPD mutations impair Nav1.7 fast inactivation and increase persistent currents. PEPD mutations also increase resurgent currents, which involve the voltage-dependent release of an open channel blocker. In contrast, IEM mutations, whenever tested, leave resurgent currents unchanged. Accordingly, the IEM deletion mutation L955 (ΔL955) fails to produce resurgent currents despite enhanced persistent currents, which have hitherto been considered a prerequisite for resurgent currents. Additionally, ΔL955 exhibits a prominent enhancement of slow inactivation (SI). We introduced mutations into Nav1.7 and Nav1.6 that either enhance or impair SI in order to investigate their effects on resurgent currents. Our results show that enhanced SI is accompanied by impaired resurgent currents, which suggests that SI may interfere with open-channel block