COORDINATIVE INTERACTION OF CHITOSAN-AZO DYES TOWARDS SELECTED FIRST ROW TRANSITION METALS

Chitosan is an abundant bio-polymer obtained by alkaline deacetylation of chitin in the exoskeleton of crustaceans. Chitosan was found to be an attractive alternative to other bio materials due to its significant physicochemical behavior and ability to selectively bind to transition and post transition metals. In order to improve the performance of this bio-polymer, chemical modification of chitosan composite and its derivatives have gained much attention. In this study, a new biopolymeric ligand was synthesized by functionalizing chitosan with eriochrome black T (EBT) and sudan III (S3) dyes. The functionalized compounds were interacted with Co(II), Ni(II), Cu(II) and Zn(II) metal ions at varied concentrations leading to complex formation. Both the new ligand and the complexes obtained at high yields were characterized using Fourier Transform Infrared (FT-IR) and Uv-Vis Spectroscopy. The FT-IR spectra revealed a possible hydrogen bonding between chitosan and the azo dye. It also suggests an interaction between the N=N of the ligand with the metal ions. In addition, the Uv-Visible spectra studies showed that on reacting various concentrations of metal ions with ligand the absorbance increases with decreasing concentration of the metal ions and was able to interact with as low as 0.001 M of the studied metal salts. &nbsp

Breastfeeding in Nigeria: A systematic review

Breastfeeding confers numerous benefits on babies and mothers. Early initiation, ‘exclusive breastfeeding’ and breastfeeding for at least two years post-delivery are the recommended practices. This study aims to examine the trends of breastfeeding practice in Nigeria by reviewing available published studies. The online databases of PubMed, Science Direct and the Web of Knowledge were searched using relevant terms. Studies identified were screened for eligibility and those that met the inclusion criteria were included in this review. Graphs and regression equations were generated using Microsoft Excel® to illustrate the duration of and trends in, breastfeeding practices in Nigeria. This review adopts the WHO standard definitions for breastfeeding categories. A total of 24 studies met the inclusion criteria but only two of these adopted the standard WHO breastfeeding categories in estimating the rates of breastfeeding. The regression equations and graphs generated show a declining trend in the rates of ‘exclusive breastfeeding’ and an increasing trend in the mean duration of breastfeeding. The rate of ‘any breastfeeding’ was high. Breastfeeding duration varies across Nigeria, a possible reflection of differences in sociocultural practices. Various reasons were cited for discontinuation of breastfeeding, the commonest of these were maternal health problems and the demands of work.Breastfeeding is commonly practiced in Nigeria. However, the rate of ‘exclusive breastfeeding’ is low and declining. It is recommended that future studies on breastfeeding in Nigeria adopt the standard WHO definitions

Determinants of neonatal mortality in rural and urban Nigeria: Evidence from a population-based national survey

Background Significant reduction in the global burden of neonatal mortality was achieved through the millennium development goals. In Nigeria, however, only a marginal reduction was realized. This study assesses the rural–urban differences in neonatal mortality rate (NMR) and the associated risk factors in Nigeria. Methods The dataset from the 2013 Nigeria demographic and health survey (NDHS), disaggregated by rural–urban residence (n = 20 449 and 9935, respectively), was explored using univariate, bivariate, and multivariable analysis. Complex samples analysis was applied to adjust for the unequal selection probabilities due to the multi-stage cluster sampling method used in the 2013 NDHS. The adjusted relationship between the outcome and predictor variables was assessed on multi-level logistic regression analysis. Results NMR for rural and urban populations was 36 and 28 deaths per 1000 live births, respectively. Risk factors in urban residence were lack of electricity access (adjusted OR [AOR], 1.555; 95%CI: 1.089–2.220), small birth size (as a proxy for low birthweight; AOR, 3.048; 95%CI: 2.047–4.537), and male gender (AOR, 1.666; 95%CI: 1.215–2.284). Risk factors in rural residence were small birth size (a proxy for low birthweight; AOR, 2.118; 95%CI: 1.600–2.804), and birth interval \u3c 2 years (AOR, 2.149; 95%CI: 1.760–2.624). Cesarean delivery was a risk factor both in rural (AOR, 5.038; 95%CI: 2.617–9.700) and urban Nigeria (AOR, 2.632; 95%CI: 1.543–4.489). Conclusions Determinants of neonatal mortality were different in rural and urban Nigeria, and rural neonates had greater risk of mortality than their urban counterparts

Prevalence of extended-spectrum beta-lactamase production in clinical Escherichia coli isolates in Ibadan metropolis, south-west Nigeria

Background: Escherichia coli is a major extended spectrum beta-lactamase-producing organism. Extended spectrum beta-lactamases (ESBLs) inactivate newer cephalosporins through hydrolysis increasing therapeutic failure and antibiotic resistance worldwide. This prospective experimental study aimed to determine the antibiotic susceptibility profile and ESBL production by clinical E. coli isolates.Methods: Fifty-one clinical E. coli isolates were obtained from the microbiology laboratories of University College Hospital, Adeoyo Maternity Hospital, Our Lady of Apostle Hospital, and a private diagnostic laboratory all in Ibadan metropolis. They were identified and confirmed using standard biochemical tests. Kirby-Bauer disc diffusion method was used to determine the antibiogram and interpreted using clinical laboratory standard institute (CLSI) guideline. ESBL production was determined by the double disk synergy test (DDST).Results: The prevalence of ESBL production was observed to be 78.4%(40). Resistance was common to sulphamethozaxole/trimethoprim 96.0%(49), ceftazidime 94.1%(48), amoxicillin and tetracycline 92.1%(47), fosfomycin 84.3%(43), cefotaxime 76.4%(39), ciprofloxacin 60.7%(31), amoxicillin/clavulanic acid 58.8%(30), and chloramphenicol 50.9%(26). Meropenem was observed to be the most sensitive (100.0%), followed by nitrofurantoin 78.4%(40), and gentamicin 70.5%(36). Multiple antibiotic resistance (MAR) index greater than 0.2 was observed in 98.0%(50) of the isolates.Conclusion: Majority of the clinical isolates of E. coli were ESBL producers which are resistant to frequently used antibiotics.Keywords: Escherichia coli, Extended spectrum beta-lactamase, Antibiotic resistanc

Climate change and malaria control: The importance of mitigation and a call to action

Malaria has remained an important target for global disease control efforts for decades. The streams of funds and, consequently, availability of effective interventions for the disease have resulted in considerable reduction in its burden, globally. Despite the relative success of such global efforts, malaria remains a significant threat in over a hundred countries, worldwide, leading to about one million deaths and hundreds of millions of hospital visits, annually. Many researchers and health commentators have argued that global warming, a consequence of climate change, could be linked – directly or indirectly – to the persistence as well as the re-emergence of malaria epidemics. Although the association between climate change and malaria spread is complex and remains a subject of controversy and debates, this paper argues that the spread and severity of malaria in several places and the increased incidences of the disease in some regions could indeed be associated with the effects and consequences of climate change. The paper maintains that the biology of the Plasmodium spp, the ecology of mosquitoes, and even the susceptibility of humans to malaria could all be affected directly/indirectly by extreme climatic events. Based on the growing body of evidence on this subject, this paper makes a call for all stakeholders to come to a consensus on the significance of climate change mitigation to malaria control, and offers some recommendations on the way forward

Comparative Study of a Fuzzy Logic Based Controller and a Neuro-Fuzzy logic Based Controller for Computer Fan

The impact of soft-computing in modern day engineering and technology cannot be overemphasized.  Fuzzy logic approach as proposed by Lofti Asker Zadeh, popularized by the Japanese, has found its way into the control of many domestic and industrial appliances/machines.  Unlike the popular PID controllers and the pulse width modulation based controllers, the performance of computer fan is investigated using the fuzzy logic approach with two inputs parameters, that is, the computer loads and the temperature and one output parameter which is the speed at which the computer fan operates.  For the fuzzy inference system, four membership functions are selected for the inputs as well as the output.  Relevant rules are set to determine the operating conditions and boundaries for the controller.  In order to make the controller adaptive, neurofuzzy logic appproach is used with parameters set as the case with fuzzy logic. Training of the controller is carried out and the performance of each controller is presented in three dimensional view and two dimensional surface view with neurofuzzy based controller, in performance, having an edge over the fuzzy logic based controller. Keywords: Anfis, Fuzzy logic, Computer fan, Controller, Performance compariso

The Use of Coconut-Shell Based Activated Carbon as an Adsorbent in the Treatment of Hard Water

One of the undesirable characteristics of some groundwater sources is hardness, which has adverse effects on water pipes, boilers and soap consumption. Therefore, several treatment processes have been introduced to remove or reduce the hardness from water. One of the innovations in this regard is coconut-shell which is readily available and could be used to produce resource materials such as activated carbon that is of public health importance. The initial values of Calcium, Magnesium and Total Hardness in the raw water sample were 120.24mg/L, 98.29mg/L and 588.00mg/L, respectively which are above the World Health Organization (WHO) standard. The highest quantities of Calcium, Magnesium and Total Hardness were removed at a contact time of 60 minutes with removal efficiencies of 80%, 60.44% and 66.71%, respectively. Also, the optimum dosage occurred at 1.2g for Calcium hardness, 1.5g for Magnesium hardness and Total hardness. In conclusion, the adsorbent obtained from the coconut-shell has the potential of removing Calcium, Magnesium and Total Hardness in water

High performance liquid chromatographic determination of proguanil after derivatisation with sodium benzoxazole-2-sulphonate

A simple, fast and reproducible method for the determination of proguanil using high performance liquid chromatographic with UV/Fluorescence detection is described. Proguanil was derivatised to its corresponding derivative [(N1-(4-chlorophenyl)-N5-(1 -methyl ethyl) imidocarbonimideamide-Nbenzoxazole]. The derivatisation reaction was conducted in methanol at 60°C using sodium benzoxazole-2-sulphonate under alkaline conditions. The resulting derivative was extracted with chloroform after which the extract was observed under UV lamp at 254 nm before TLC and HPLC analysis. Similarly, the derivatisation process was adapted for derivatisation of proguanil in urine sample. The reaction proceeded smoothly and rapidly. The extraction process was not cumbersome and eliminated the need for costly extraction and evaporation equipments. The resulting derivative fluorensced intensely under UV lamp. Direct HPLC analysis of the reaction mixture was found possible without interferences from excess reagent and endogeneous compounds like ammonium salts. The derivative eluted in less than seven minutes thus making the method suitable for routine use. The calibration plot was linear over the concentration range. A correlation regression of the order of 0.94 was obtained from the calibration curve which indicated a strong relationship between the instrument response and the concentration of proguanil. The discussion also summarizes the derivatisation chemistry that have not being fully explored to date but may find utility in future development of highly sensitive analytical methods for biquanide drugs

Syntheses, characterizations and antioxidant activities of copper complexes of quercetin as influenced by redox states

Copper is an essential element for living but imbalance between Cu+ and Cu2+ produces free radicals. Quercetin is an effective metal chelator and its chelates are often better free radical scavengers than free quercetin. In this study, the syntheses, characterizations, antioxidant activities of quercetin as well as its Cu (I) and Cu (II) complexes using UV-VIS, IR spectrometric methods, and 2,2-diphenyl 1-picrylhydrazyl (DPPH) scavenging assay were investigated. 1:1 and 2:1 stoichiometric ratios were obtained for the dark-brown Cu+ and green Cu2+ quercetin complexes respectively. Bathochromic shifts from 268 nm (band II) and 362 nm (band I) in quercetin were observed at 302 nm and 386 nm for Cu (I) –quercetin complex and at 281 nm and 394 nm for Cu (II) - quercetin complex. FT-IR showed shifts in the positions of carbonyl and hydroxyl groups with presence of bands at 932.01 cm-1 in Cu (I) – quercetin and 928.57 cm-1 in Cu (II) – quercetin confirming complexation. Both complexes were better free radical scavengers than free quercetin with Cu (I)-quercetin complex having the highest antioxidant activity. Higher antioxidant activity and differences in spectra characters of Cu (I) quercetin complex are related to relative stability of fully filled orbital of Cu+ over Cu2+.© 2015 International Formulae Group. All rights reserved.Keywords: Oxidation state, relative stability, DPPH, Stoichiometric ratio, complexatio