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Quantitative Structure Activity Relationship Analysis of Selected Chalcone Derivatives as Mycobacterium tuberculosis Inhibitors  [PDF]
Alisi Ikechukwu Ogadimma, Uzairu Adamu
Open Access Library Journal (OALib Journal) , 2016, DOI: 10.4236/oalib.1102432
Abstract: In order to gain further insights into the structural requirements for anti-tuberculosis activity by chalcone derivatives of 1,3-diphenylprop-2-ene-1-one, quantitative structure activity relationship (QSAR) was performed using genetic function approximation (GFA). Geometry optimization was achieved at the density functional theory (DFT) level using Becke’s three-parameter Lee-Yang- Parr hybrid functional (B3LYP) in combination with the 6-31G* basis set. Subsequently, quantum chemical and molecular descriptors were generated and divided into training and test sets by Kennard Stone algorithm. Internal and external validations as well as Y-randomization tests were employed in model validation. Five predictive models were generated by GFA. The generated models showed that constitutional indices, 2D autocorrelations and radial distribution function (RDF) descriptors were important contributors to anti-tuberculosis activity of 1,3-diphenylprop-2-ene-1-one derivatives. Based on validation results, model 4 was chosen as the best of the five models.
MNDO and DFT Computational Study on the Mechanism of the Oxidation of 1,2-Diphenylhydrazine by Iodine
Gideon A. Shallangwa,Adamu Uzairu,Victor O. Ajibola,Hamza Abba
ISRN Physical Chemistry , 2014, DOI: 10.1155/2014/592850
Abstract: The reaction mechanisms of the oxidation of 1,2-diphenylhydrazine by iodine have been examined using semiempirical and density functional theory methods, the oxidation proceeded via two independent pathways that can be separately monitored. One pathway involved the chain multistep mechanism. The other pathway occurred via a one-step mechanism in which a “cyclic” activated complex was formed which on disproportionation gave the products. The one-step “cyclic” activated complex mechanism proceeds more rapidly than the chain multistep mechanism. The results were explained by analyses based on computational energetics of the optimised reactants, intermediates, transition states, and products of the reaction of iodine with 1,2-diphenylhydrazine. 1. Introduction 1,2-Diphenylhydrazine is used as an antisludging additive to motor oil, a desuckering agent for tobacco plants, a reductant in the reclamation of rubber, a component of experimental organometallic polymers, an ingredient in photochromic resin compositions, and a component in polymerization reactions [1, 2]. It is also used in the manufacture of hydrogen peroxide [1, 2]. Some 1,2-diphenylhydrazine derivatives are used as flame-retardant agents [3]. Several aryl hydrazine interactions in small molecule complexes have been studied to see how they might react with iron and other substances [4]. Some of the studies found that a 3?mM solution of benzene completely disproportionate 6 equivalents of 1,2-diphenylhydrazine into aniline and azobenzene. The effort of study to shift the chemistry in a different direction was only partially successful. Several others [5–9] have also reported that the reactions of 1,2-diphenylhydrazine and its derivatives were pH dependent and would yield different products depending on the PH of the reaction medium. These studies [4–9] concluded that 1,2-diphenylhydrazine and its derivatives enjoy complicated chemistries that include structural rearrangement and disproportionation and that their interactions with metal ions or inorganic substances are complex and incompletely understood. Although 1,2-diphenylhydrazine is known to be oxidized readily by many oxidants [10–17], only in a few other cases have the reaction mechanisms been examined, especially its reaction mechanisms with iodine [14]. It is also noteworthy to state that the various mechanisms proposed were not conclusive and needed to be revisited. Iodine, on the other hand, is an essential component of the human diet, and in fact, appears to be the heaviest required element in a diet. Iodine compounds are useful in
Seasonal Quality Assessment of Agricultural Soils along the Bank of Tungan Kawo Dam, Kontagora, Nigeria  [PDF]
Musa Sabo Abdullahi, Adamu Uzairu, Oluwole Joshua Okunola, Muhammad Lawal Balarabe
Journal of Agricultural Chemistry and Environment (JACEN) , 2016, DOI: 10.4236/jacen.2016.53015
Abstract: This research work studies the impacts of irrigation and other agricultural practices on the soil along the bank of Tungan Kawo dam. The experimental analysis evaluates the soil physicochemical parameters and metal (Cd, Cu, Cr, Ni, Fe, Mn, Pb and Zn) concentrations using sequential extractions. The physicochemical parameters of the soils across the sites indicated values reported for less polluted soils. Also, analysis of total metals in the soils indicated lower concentration of all metals evaluated than recommended standard limits with exception of Cd. The results of sequen tial extraction of heavy metal in soil sample indicated that all metals were mainly associated with the residual, Fe-MnO and organic bound fractions. The residual fraction has the maximum concentration of metals especially in cool and dry season for Cr, Cu, Ni, Pb and Zn, whereas only a small fraction of all the heavy metal is extracted in water soluble, exchangeable and carbonate bound fractions. It indicates that the bioavailability index is low. Hence, mobility of the heavy metals by the surrounding plants grown on the soils is low.
Comparative performance of HbA1c 6.5% for FPG ≥ 7.0 vs 2hr PG≥ 11.1 criteria for diagnosis of Type 2 diabetes
AN Adamu
African Health Sciences , 2011,
Abstract: Background: International expert committee on the use of HbA1c to diagnose diabetes mellitus in 2009 and World Health Organization (WHO) in 2011 has advocated the use of HbA1c to diagnose diabetes mellitus. Objective: To determine and compare the relationship between the new cut off value of HbA1c with established criteria. Methods: Thirty-one hypertensive subjects attending Lagos University Teaching Hospital were recruited for HbA1c and standard oral glucose tolerance test. Fasting plasma glucose (FPG) and two-hour plasma glucose (2hrpp) value of e”126mg/dl and >200mg/dl were used as standard respectively for diagnosis of diabetes. The HbA1c of e”6.5% was used to diagnose diabetes. The performance and correlation of HbA1c with FPG and 2hrpp were calculated and results were compared. Results: Mean age of the subjects was 53.97±6.27years. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), efficiency and correlation of FPG is 50%, 68%, 27%, 85%, 64% and 0.5 respectively while the sensitivity, specificity, PPV, NPV, efficiency and correlation of 2hrpp is 73.91%, 62.5%,85%, 41.66%, 70.97% and 0.73% respectively. There was a significant difference between FPG and 2hrpp interms of sensitivity, PPV and NPV. Conclusion: The results of HbA1c with 2hrpp has better correlation, sensitivity, and PPV compared to HbA1c with FPG.
An Appraisal of the Crisis in Darfur in Western Sudan and the Prospect for a Lasting Peace
MM Adamu
African Research Review , 2008,
Abstract: The Darfur crisis in western Sudan started in February 2003. It has to date claimed the lives of an estimated number of 200,000 people and another 2.5 million have been displaced and are now living in make shift refugee camps in Chad and neighbouring countries. All attempts to broker peace among the major warring factions had proved abortive and there is little or no hope that the displaced people would one day return to their villages. The killings, raping, suffering and starvation had continued despite the presence of the African Union troops which numbered about 7000 and deployed since 2004. A lot of propaganda, misinformation, fabrications and distortions have gone across to the public in trying to explain the causes and attendant consequence of the said conflict. These have clearly stood on the way to a real understanding of the genesis of the crisis for a lasting peace to be obtained and peace building to be accelerated, and end this bloodshed and suffering that had been the bane of the region for the past five years. This paper is an appraisal of the various views and opinions that had been put forward by different interest groups on the causes of the crisis, its impact and the way forward towards the attainment of peace. African Research Review Vol. 2 (3) 2008: pp. 315-333
The Legend of Queen Sheba, the Solomonic Dynasty and Ethiopian History: An Analysis
MM Adamu
African Research Review , 2009,
Abstract: The legend of Queen Sheba is undoubtedly one of the oldest legends, producing the oldest monarchy in Africa comparable, perhaps, only to the imperial dynasty in Japan or the Seifuwa dynasty in the Lake Chad basin. It is clearly one of the most accepted, believed, pervasive and resonant among all the legends of origin in Africa, today. The legend is still widely believed by the majority of Ethiopians and is reflected in their day to day daily lives. The existence of the Orthodox Tewahido church and other religious ceremonies, the presence of Beta Israel, the names of people like Makeda or Sheba and organizations such as the Sheba Miles are all testimonies to the legend living in the present Ethiopian communities. It purported to explain how the Ethiopian ruling dynasty ‘the Solomonic dynasty’ was descended from Solomon and through him from Abraham and the early patriarchs. The dynasty followed a succession of rulers from Yekunno- Amlak in circa 1270AD to the last emperor in the person of Haile- Selassie 1 who was deposed in 1974. This has lasted for a period close to a thousand years and making the dynasty to be one of the longest and oldest monarchies anywhere in the world. This paper is intended to look more closely at some of the claims made by this legend and its implication on the Ethiopian peoples, their heritage and identity. It is strongly argued that the legend is only legendary and a historical travesty. It cannot be proven historically. The paper concluded by examining the political as well as the socio-economic significance of the legend in contemporary discours.
The Somalian Crisis: A Legacy of Colonialism?
MM Adamu
African Research Review , 2009,
Abstract: The Somalian crisis seemed to have defied all solutions since its inception in1991. The country had become increasingly ungovernable and the condition had been described as the worst humanitarian crisis in the world. Somalia is considered by many to be a ‘failed state’ being the only state in the world with a vacant seat at the United Nations. It is not that it has been abolished but that it has entered what some analysts have called an undetermined ‘Gray Zone’. All these have been as a result of the crisis that engulfed the country since the fall of the regime of Siyyad Barre almost two decades ago and further complicated by the Ethiopian /American invasion of 2006. This paper examines the roots of the crisis, the attempts made at reconciliation as well as the role of international bodies in averting or escalating the crisis. The paper also looks at the possibility of finding a lasting peace in the country. It is argued that the Somalian crisis should be largely seen as a legacy of colonialism in the country as well as the misdeeds of some people like Siyyad Barre. The paper shows that the only way to peace is to allow the Somalians to determine the manner in which they want to be ruled.
Fourier Transform Infrared Spectroscopic Determination of Shale Minerals in Reservoir Rocks
MB Adamu
Nigerian Journal of Basic and Applied Sciences , 2010,
Abstract: Attenuated Total Reflectance Fourier transform infrared spectroscopy together with multivariate statistical regression was used to produce calibrations between spectra of standard mineral mixtures and gas shale reservoir rocks. A Classical Least Square (CLS) model was developed from the attenuated spectra of mixtures of five mineral standards chosen to represent the most frequently encountered minerals in shale-type reservoir rocks namely: quartz, illite/smectite (30:70), kaolinite, calcite and dolomite. The CLS model developed was able to quantify the mineral components of independent mixtures with an absolute error between 1 to 3wt% for all the pure minerals in the mixtures. Samples from a suite of shale reservoir rocks were analysed using standard Quantitative X-Ray Diffraction (QXRD) and with FTIR. Unknown mineral concentrations in the samples were then predicted using spectra and the calibration equations. Good correlations were achieved between the QXRD and ATR-CLS predicted concentrations (r2>0.8), with average absolute error of between 1 to 6wt%. This provides evidence that attenuated FTIR is a promising method for rapid and accurate determination of minerals in reservoir rocks for building higher resolution data without additional time consuming and expensive traditional analyses.
Achalasia: What is the best treatment?
Ahmed Adamu
Annals of African Medicine , 2008,
Abstract: Background: Achalasia is an infrequent primary motility disorder of the esophagus. Because of uncertain etiology, treatment is only palliative and is directed at decreasing lower esophageal sphincter pressure, improving esophageal emptying and relieving the symptoms of achalasia. Current treatment options include pharmacological, endoscopic and surgical. We undertook a systematic literature review of the management strategies currently available for achalasia. Method: A Medline, PubMed and Cochrane database search was conducted using reference manager 11. Original articles and reviews published in the English literature on the management of achalasia were reviewed. Emphasis was placed on articles published in the last ten years on randomized controlled trials comparing the various forms of treatment. Results: Esophageal manometry is the standard diagnostic evaluation for achalasia. Accurate diagnosis can also be made based on clinical findings and barium esophagogram. Medical treatment with nitrates or calcium channel blockers has variable results in alleviating the symptoms of achalasia but long-term results are disappointing because of tolerance and side effects. Intrasphincteric injection of botulinum toxin, pneumatic dilatation and surgical myotomy are variably effective at controlling the symptoms of achalasia but each modality has specific strength and weaknesses which make their choice suitable in a particular group of patients. While pneumatic dilatation is superior to botulinum toxin injection surgical myotomy provides the best long-term control of symptoms in patients with achalasia. Conclusion: Laparoscopic myotomy should be the initial treatment for most patients with achalasia. Pneumatic dilatation is the most cost-effective alternative but its long-term efficacy is less than that of surgical myotomy. Endoscopic botulinum toxin injection can be considered when other forms of treatment are contraindicated.
The Utopian Quest in Bessie Head’s When Rain Clouds Gather and Maru
Adamu Pangmeshi
Rupkatha Journal on Interdisciplinary Studies in Humanities , 2009,
Abstract: Prior to Nelson Mandela’s ascension to power in South Africa, literature of the country had been essentially a protest against the dehumanizing treatment that was meted on the Blacks by the minority Whites who were at the helm of power through the policy of apartheid. This somehow created socio-political upheavals and a pervasive atmosphere. Consequently, some writers while unfolding this social enigma, did so with a vision of proposing an ideal society for humanity. One of them is Bessie Head. This paper seeks to examine Head’s When Rain Clouds Gather and Maru in a bid to demonstrate that her quest for a perfect society has been provoked by her experiences in life and the dystopian South African. Informed by new historicism, it is argued that an ideal or a perfect society is a figment of the imagination.
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