Nephroprotective properties of the methanol stem extract of Abrus precatorius on gentamicin-induced renal damage in rats

Background The use of plants for the treatment and prevention of diseases in man and his animals has led to a renewed scientific interest in the use of medicinal plants for therapeutic purposes. The nephroprotective properties of methanol stem bark extract of Abrus precatorius against gentamicin-induced renal damage in rats was evaluated in this study. Methods Thirty male Wistar rats were divided into five equal groups. Group A was the negative control group while B was the positive control group which received gentamicin 100 mg/kg intra-peritoneally for 6 days. Group C were pretreated with 100 mg/kg extract for the 3 days and then concurrently with gentamicin 100 mg/kg for 3 days and group D were pretreated with 200 mg/kg extract for 3 days and then concurrently with gentamicin 100 mg/kg for 3 days. Group E received gentamicin intraperitoneally for 6 days followed by administration of 200 mg/kg of the extract for 3 days. Blood samples, kidneys and kidney homogenates were collected for haematological, biochemical, histopathological and immunohistochemical analysis. Results The results showed that no significant haematological changes were noted. The groups treated with extract exhibited significant increase in body weight gain. While group B significantly exhibited focal areas of inflammation, fatty degeneration, congestion of vessels, tubular necrosis and glomerular atrophy, the lesions were mild with the treated groups. Treated groups exhibited a dose dependent significant decrease in serum creatinine, urea, XO, NO and Myeloperoxidase, AOPP, Protein carbonyl, H2O2 generated and MDA levels when compared with group B. There were significant dose dependent improvements in SOD, GST, GSH, Protein thiol, and non-protein thiol levels in the treated groups when compared with group B. In immunohistochemistry, Group B exhibited over expression of CRP and NF-κB levels, and marked reduction in expression of Bcl-2 while the reverse was seen in the groups treated with methanol extracts of Abrus precatorius. Conclusion The methanol extract of Abrus precatorius plays a vital role against gentamicin induced renal damage by reducing levels of renal markers of oxidative stress, inflammation and apoptosis, enhancing enzymatic and non enzymatic renal antioxidant system, alongside an increase in Bcl-2 and a decrease in NF-κB and CRP expressions.

Combining Google Earth historical imagery and UAV photogrammetry for urban development analysis

Rural-urban migration often triggers additional demand for housing and infrastructural development to cater for the growing population in urban areas. Consequently, town planners and urban development authorities need to understand the urban development trend to make sustainable urban planning decisions. Yet, methods to analyse changes and trends in urban spatial development are often complex and require costly data collection. This article thus presents a simplified method to analyse the urban development trend in an area. The method integrates Google Earth (GE) historical imagery (baseline data) and unmanned aerial vehicle (UAV) photogrammetry (recent data) to quantify the changes over time. This approach can be applied to study the urban development trends in low-income countries with budget constraints. The method is discussed under four main headings: (1) background, (2) method details, (3) limitations, and (4) conclusion.•Google Earth historical image can be extracted with its associated world file.•The population of an area can be estimated by using average household size data and the number of residential buildings in the area.•The building height ratio can be used to ascertain if the land is being used parsimoniously.

An assessment of the spatio-temporal dynamics of Landsat-derived aerosol concentration in relation with land cover and road networks in the Lagos megacity

The interrelationships between air quality, land cover change, and road networks in the Lagos megacity have not been explored. Globally, there are knowledge gaps in understanding these dynamics, especially using remote sensing data. This study used multi-temporal and multi-spectral Landsat imageries at four epochs (2002, 2013, 2015, and 2020) to evaluate the aerosol optical thickness (AOT) levels in relation to land cover and road networks in the Lagos megacity. A look-up table (LUT) was generated using Py6S, a python-based 6S module, to simulate the AOT using land surface reflectance and top of atmosphere reflectance. A comparative assessment of the method against in situ measurements of particulate matter (PM) at different locations shows a strong positive correlation between the imagery-derived AOT values and the PMs. The AOT concentration across the land cover and road networks showed an increasing trend from 2002 to 2020, which could be explained by urbanization in the megacity. The higher concentration of AOT along the major roads is attributed to the high air pollutants released from vehicles, including home/office generators and industries along the road corridors. The continuous rise in pollutant values requires urgent intervention and mitigation efforts. Remote sensing-based AOT monitoring is a possible solution.