Novel quinoxaline compound against extended-spectrum beta-lactamases producing bacteria.

OBJECTIVE: Extended-spectrum beta-lactamases (ESBLs) targeting beta-lactam antibiotics pose a major healthcare challenge. Carbapenems are known to be less impacted. However, the emergence of carbapenem-resistant strains can add further complexity to this existing challenge. With slow drug discovery and rapid resistance, repurposing existing drugs is crucial. This research study aims to provide insight into the antimicrobial effectiveness of 3-hydrazinoquinoxaline-2-thiol against diverse clinical ESBL-producing isolates. MATERIALS AND METHODS: The broth microdilution assay was conducted on a total of sixty-nine clinical ESBL-producing isolates to assess the minimum inhibitory concentrations (MICs) of 3-hydrazinoquinoxaline-2-thiol. The assay was conducted in triplicate, and the average MIC values were calculated. RESULTS: The most repeatedly observed MIC was 64 µg/ml (37.7%), followed by 256 µg/ml (23.2%) and 128 µg/ml (17.4%). Other MICs: 32 µg/ml (11.6%), 16 µg/ml (7.2%), 4-8 µg/ml (1.4%). CONCLUSIONS: This study demonstrated an effect of 3-hydrazinoquinoxaline-2-thiol on various ESBL-producing strains in vitro, indicating its promising therapeutic potential. To comprehensively understand the drug, rigorous testing, including pharmacokinetics, resistance assays, safety assessments, and exploration of potential synergies with other antibiotics against ESBL-producing organisms, is crucial.

Seasonal quality variation and environmental risks associated with the consumption of surface water: implication from the Landzun Stream, Bida Nigeria.

Water constitutes a major environmental and public health concerns worldwide. A large proportion of global water consumption is sourced from surface water. The dependency level on surface water is higher in developing countries, especially in rural-to-semi-urban areas, where subsurface water is not accessible. Presented in this paper is a spatiotemporal and hydrochemical quality assessment of the spring-originated Landzun Stream in Bida, Nigeria; which is usually consumed in its untreated state. Water samples were systematically collected in eighteen locations along the stream channel in both rainy and dry seasons at an equidistance interval of 500m. On-site and laboratory measurement of important physical and hydrochemical parameters were carried out using standard procedures. Water temperature in the rainy season (34-37 °C) slightly exceeds measured values in the dry season (29-33 °C). 72.22% (rainy) and 83.33% (dry) of collected samples did not meet the odourless requirement for drinking water. Similarly, estimated percentages of 66.67 and 94.44 of collected samples in rainy and dry seasons respectively have a taste. Contrary to data in the rainy season, 89%, 11%, 67% and 56% of the dry season's samples were enriched in magnesium (Mg), lead (Pb), potassium (K) and iron (Fe) respectively above the 2018 World Health Organisation guidelines for drinking water. This study further established that seasonal variation plays a major role in altering the aesthetic surface water quality. The intake of untreated surface water is a vehicle for potential water-borne diseases and allergies, hence alternative sources of drinking water for the populace dependent on the Landzun Stream is recommended to reduce risks and possible dangers of consuming the stream water.

Estimating sediment yield at Kaduna watershed, Nigeria using soil and water assessment tool (SWAT) model.

Over the years, sedimentation has posed a great danger to the storage capacity of hydropower reservoirs. Good understanding of the transport system and hydrological processes in the dam is very crucial to its sustainability. Under optimal functionality, the Shiroro dam in Northern Nigeria can generate ∼600 MW, which is ideally sufficient to power about 404,000 household. Unfortunately, there have not been reliable monitoring measures to assess yield in the upstream, where sediments are sourced into the dam. In this study, we applied the Soil and Water Assessment Tool (SWAT) to predict the hydrological processes, the sediment transport mechanism and sediment yield between 1990 and 2018 in Kaduna watershed (32,124 km2) located upstream of the dam. The model was calibrated and validated using observed flow and suspended sediment concentration (SSC) data. Performance evaluation of the model was achieved statistically using Nash-Sutcliffe (NS), coefficient of determination (r2) and percentage of observed data (p-factor). SWAT model evaluation using NS (0.71), r2 (0.80) and p-factors of 0.86 suggests that the model performed satisfactorily for streamflow and sediment yield predictions. The model identified the threshold depth of water (GWQMN.gw) and base flow (ALPHA_BF.gw) as the most sensitive parameters for streamflow and sediment yield estimation in the watershed. Our finding showed that an estimated suspended sediment yield of about 84.1 t/ha/yr was deposited within the period under study. Basins 67, 71 and 62 have erosion prone area with the highest sediment values of 79.4, 75.1 and 73.8 t/h respectively. Best management practice is highly recommended for the dam sustainability, because of the proximity of erosion-prone basins to the dam.

In vivo evaluation of a closed loop monitoring strategy for induced paralysis.

OBJECTIVE: Reliable closed loop infusion systems for regulating paralysis level can be a great convenience to the anesthesiologists in automating their task. This paper describes the in vivo performance evaluation of a self-tuning controller that is designed to accommodate large variations in patient drug sensitivity, drug action delays and environmental interfering noise. METHODS: The infusion system was evaluated in six adult mongrel dogs. Following the manual induction of paralysis by an anesthesiologist, the controller regulated the infusion of vecuronium to maintain a desired level of paralysis. The integrated EMG response of the hypothenar muscle to a train-of-four stimulation of the ulnar nerve quantified the depth of paralysis. The controller's robustness was tested by contaminating the sensed twitch signal with electrocautery noise and electrode disconnection. RESULTS: The controller reached the initial level of paralysis of 100% in about 4.0 minutes and arrived at the desired level of 90% with an overshoot of 6.38% (+/-6.82). It maintained the desired level of paralysis with a 2.04% (+/-1.20) mean offset at 90% and 0.4% (+/-0.5) mean offset at 80% steady state level, respectively. The mean infusion rate to sustain 90% and 80% paralysis were 2.70 (+/-2.05) and 2.15 (+/-2.57) ((mg/kg)/min), respectively. CONCLUSIONS: The system adapted to a large variation in the sample subject drug sensitivity. It remained stable despite large amplitude disturbances and maintained the paralysis at the desired level following the removal of the disturbances.