137 research outputs found
Synthesis, characterization and antibacterial studies of metal complexes of sulfadiazine with N-alkyl-N-phenyldithiocarbamate
Co(II), Cu(II), Pd(II) and Pt(II) complexes of 4-amino-N-(2-pyrimidinyl)benzene sulfonamide (sulfadiazine) with some N-alkyl-N-phenyl dithiocarbamate have been synthesized and characterized by elemental analysis, conductivity measurements, UV-Vis and FTIR spectroscopy. The complexes are formulated as four coordinate MN2S2 species in which the metal ions are coordinated to one molecule of sulfadiazine through the pyrimidinyl and sulfulnamido nitrogen atoms and one molecule of dithiocarbamate through two sulfur atoms with both molecules acting as bidentate chelating ligands. The in vitro antibacterial activities of the complexes and sulfadiazine were evaluated against eight bacteria strains using the agar well diffusion method. The metal complexes showed varied antibacterial properties and their minimum inhibitory concentration (MIC) and maximum bactericidal concentration (MBC) were determined.Ā KEY WORDS: Sulfadiane, Dithiocarbamate, Metal complexes, Antibacterial, Drug resistanceĀ Bull. Chem. Soc. Ethiop. 2013, 27(1), 77-84.DOI: http://dx.doi.org/10.4314/bcse.v27i1.
Synthesis, characterization and antibacterial screening of 2,4-diaminopyrimidine pyrimethamine and trimethoprim silver complexes
Air stable silver Ag(I) complexes of pyrimethamine and trimethoprim drugs have been synthesized and characterized by elemental analysis, Fourier transform infrared (FTIR) and ultraviolet visible (UV-Vis) spectroscopy, and conductivity measurement. The metal complexes formed a three and four coordinate geometry with the ligands acting as a monodentate molecule bonding to the silver ion in each case through the pyrimidine N (1) nitrogen. The complexes have non-electrolyte behaviour in dimethylformamide (DMF) solution with its low conductivity values. Silver complexes, their free ligands alongside the corresponding silver salts were screened against selected bacterial isolates. All the silver complexes showed enhanced antibacterial activities compared to their free ligands and potential antibacterial agents have been identified.Key words: Pyrimethamine, trimethoprim, silver complexes, antibacterial screening, minimum inhibitory concentration
The Distribution of the Inverse Square Root Transformed Error Component of the Multiplicative Time Series Model
The probability density function, mean and variance of the inverse square-root transformed left-truncated N(1,Ļ2) error component e*t(=1/ āet) of the multiplicative time series model were established. A comparison of key-statistical properties of e*t and et confirmed normality with mean 1 but with Var(e*t) ā1/4Var(et) when Ļā¤0.14. Hence Ļā¤0.14 is the required condition for successful transformation
Radiological Status of Drinking Water Sources Around a Coal Mining Site in Kogi State, North Central Nigeria
The radioactivity of drinking water sources around Okaba coal mining area in Ankpa local government area of Kogi state, North central Nigeria have been carried out using a low background Gasless Alpha- Beta Counting System (Protean Instrument Corporation) ā MPC 2000DP. The gross alpha and gross beta activity of water samples from four (4) sources (river/stream, borehole, sachet water and rain water) was measured. The grossalphaand gross-beta activity concentrations recorded were below the safe limits of 0.5 Bq/l and 1 Bq/l respectively, as recommended by the world health organization (WHO, 2017). Also, results of the committed effective dose (for adult and infant) calculated were all below the reference dose level (RDL) of 0.1mSv/yr (WHO, 2017) except for BW3 whose adult dose was above the RDL. Therefore, there is no immediate risk of internal radiation exposure to the populace via intake of water from the four major sources of drinking water around Okaba coal mining area. However, caution should be taken especially with regards long-term consumption of the ground water (BW3).
Keywords: Okaba, radioactivity, gross-alpha, gross-beta, coal, wate
On the use of drains in orthopedic and trauma
Introduction: The use of drains in trauma and Orthopaedic practice has been affected by the concept of evidence based medicine that has become accepted as standard of care for all surgical or medical practice, which questions all care processes that cannot be backed by evidence to be beneficial to the patient. There have been a large number of multi centre meta-analytical studies that found drains to be of little or no benefit in trauma and Orthopaedic operations. Because of these studies, there are few situations where drains are routinely used e.g. Calcaneal fractures in developed countries. Even major procedures like total knee and arthroplasties are being performed without drains. We set to findout whether such evidence can be found in our practice.Materials and Methods: Between 2004 and 2012, eighty six patientsĀ matched for sex and type of injury and operative procedures to be done were prospectively selected and assigned to use or no use of drains in their operations. Complications like haematoma, drain migration, infection, inadvertent drain stitching were observed in the two groups.Results: Eighty six major orthopaedic operations were studied. There was no evidence of occurrence of complication arising from non use of drains in the undrained group. Those patients whose wounds were drained had noĀ Ā need for drain change thus making the wound care less eventfulConclusion: Postoperative wound drains make for neat postoperative period with less tissue swelling. There was no statistically significantĀ differences between the drained and undrained wounds in terms ofĀ infection rates, haematoma or seroma formation.Key words: Drains, drained surgical wounds, undrained surgical wound
REVIEW ON ENVIRONMENTAL IMPACT AND VALOURIZATION OF WASTE COOKING OIL
There is a large volume of waste cooking oil (WCO) in the world, which has made waste management extremely difficult. The main purpose of the large-scale organized collection of WCO is the synthesis of biodiesel. Although alternative applications are equally important and necessitate attention, the majority of studies focus primarily on the synthesis of biodiesel from WCO. The major objective of this review paper is to draw attention to the potential environmental implications of used cooking oil as well as its potential for reuse in products other than biodiesel. It can be transformed into direct-burn energy, biodiesel, hydrogen gas, pyrolytic oil, or hydrogen. Applications like combined heat and power generation (CHP) are where WCO is most useful. Additionally, it can be chemically processed to create biodegradable polyurethane sheets, soaps, alkyd resins, greases, and lubricants. WCO is a carbon source that can be used in fermentation processes to create polyhydroxybutyrate and rhamnolipid biosurfactant after being completely cleaned and sterilized. Therefore, waste cooking oil can be viewed as a waste that can be converted into energy or used as a catalyst for biological or chemical processes
Assessment of Charcoal Production and Its Impact on Deforestation and Environment in Borgu Local Government Area of Niger State, Nigeria
Commercial charcoal production is gradually becoming one of the major sources of sustenance and currently plays a major role in promoting entrepreneurial development in Borgu Local Government Area of Niger State. The study was carried out to assess charcoal production and its impact on deforestation and environment in the study area. Data for the study were generated from a structured questionnaire administered to charcoal producers in the study area. Data obtained revealed that majority (83%) were male with 56% within the age class of 21-40, majority (67%) were married and about (51%) attained primary education. Majority of the producers (82%) used traditional earth mound kiln method for charcoal production and about 56% of the producers obtained their raw material from free area. Most preferred tree species for charcoal production was Prosopis africana and accounted for 61%. Loss of biodiversity ranked 1st as regards impact of charcoal production on deforestation and environment in the study area, closely followed by forest degradation and soil degradation respectively. This study will enable forestry policy makers, charcoal producers, and farmers in the study area to be better informed about the implications of charcoal production on deforestation and environment and seek innovative means and ways to combat its menace
Simvastatin inhibits TLR8 signaling in primary human monocytes and spontaneous TNF production from rheumatoid synovial membrane cultures
Simvastatin has been shown to have anti-inflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these anti-inflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on Toll-like receptor (TLR) signalling in primary human monocytes was investigated. A short pre-treatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor-Ī± (TNF) in response to TLR8 (but not TLRs 2, 4, or 5) activation. Statins are known inhibitors of the cholesterol biosynthetic pathway, but intriguingly TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate; downstream products of cholesterol biosynthesis. TLR8 signalling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited IKKĪ±/Ī² phosphorylation and subsequent NF-ĪŗB activation without affecting the pathway to AP-1. Since simvastatin has been reported to have anti-inflammatory effects in RA patients and TLR8 signalling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signalling that may in part explain its beneficial anti-inflammatory effects
Advances in ecotechnological methods for diffuse nutrient pollution control: wicked issues in agricultural and urban watersheds
Considerable time and funding have been committed to tackling nonpoint source (NPS) pollution in agricultural and urban watersheds . Notwithstanding all these efforts, the water quality in many AUWs has not significantly improved. Diffuse nutrient pollution involves the movement of these pollutants between soil and water. Excessive diffuse pollution has been accepted as one of the main causes of failure to attain favorable environmental conditions in freshwater systems. Recently, several technologies and practices have been implemented to manage diffuse pollution, namely: a) source reduction, b) pollutant retention over the movement process; c) nutrient recycling, and d) purification and restoration of the eutrophic water bodies. This paper synthesized the existing knowledge of key methods to tackle diffuse pollution from AUWs. Furthermore, the predominant purification mechanisms and impacting factors are explored, allowing a comprehensive and critical understanding of different control strategies to improve the management of diffuse pollution. Therefore, potential approaches for strengthening the performance of control technologies for diffuse pollution treatment and remediation are discussed. Although adopting source reduction strategies (e.g., the ā4Rā approach: right rate, right time, right source, and right placement of nutrients) could efficiently decrease surface runoff and pollutant levels, they may not stop runoff from entering nearby streams. Consequently, comprehensive treatment of agricultural runoff still requires extra process retention strategies. Overall, the findings of this paper showed that treatment system design and operational and environmental factors played crucial but variable roles in diffuse pollution treatment. Moreover, the results showed that combining or integrating constructed wetlands with other control technologies could enhance the comprehensive purification of diffuse pollution compared to using a single method. This review proposes a systematic approach for diffuse pollution control based on three components (water, soil and microbiota) and maximizing the regulating services of agroecosystems via land use/cover types. The current review contributes to the documentation of existing research trends. It sheds light on diffuse pollution control approaches in AUWs, and further encourages the development of this vital field
Climate change adaptation in conflict-affected countries:A systematic assessment of evidence
People affected by conflict are particularly vulnerable to climate shocks and climate change, yet little is known about climate change adaptation in fragile contexts. While climate events are one of the many contributing drivers of conflict, feedback from conflict increases vulnerability, thereby creating conditions for a vicious cycle of conflict. In this study, we carry out a systematic review of peer-reviewed literature, taking from the Global Adaptation Mapping Initiative (GAMI) dataset to documenting climate change adaptation occurring in 15 conflict-affected countries and compare the findings with records of climate adaptation finance flows and climate-related disasters in each country. Academic literature is sparse for most conflict-affected countries, and available studies tend to have a narrow focus, particularly on agriculture-related adaptation in rural contexts and adaptation by low-income actors. In contrast, multilateral and bilateral funding for climate change adaptation addresses a greater diversity of adaptation needs, including water systems, humanitarian programming, and urban areas. Even among the conflict-affected countries selected, we find disparity, with several countries being the focus of substantial research and funding, and others seeing little to none. Results indicate that people in conflict-affected contexts are adapting to climate change, but there is a pressing need for diverse scholarship across various sectors that documents a broader range of adaptation types and their results
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