Mn(II), Co(II), Ni(II), and Cu(II) complexes of amino acid derived Schiff base ligand: Synthesis, characterization and in-vitro antibacterial investigations

Four complexes of Mn(II), Co(II), Ni(II) and Cu(II) with Schiff base ligand (H3L) derived from 2-amino-3-methylbutanoic acid and acetylacetonate were synthesized. All complexes were characterized by elemental analysis, Fourier-transform infrared spectroscopy and electronic spectroscopy. The results confirmed the coordination of the ligand to metals in tridentate fashion via the hydroxyl oxygen, the azomethine nitrogen and the enolic acetylacetonate oxygen. Antimicrobial activities were established for all complexes, free ligand and ciprofloxacin for comparison. Both the ligand and its metal complexes were active against Gram-positive and negative bacterial strains. The Cu(II) complex, showed highest antibacterial activity among the complexes screened. Other complexes displayed considerable antibacterial activity. Octahedral geometry was proposed for the metal(II) complexes with the Schiff base.                     KEY WORDS: Schiff base, Amino acid, Metal Complexes, Antibacterial agents   Bull. Chem. Soc. Ethiop. 2021, 35(1), 97-106. DOI: https://dx.doi.org/10.4314/bcse.v35i1.

Oral health awareness, practices and status of patients with diabetes attending a tertiary health institution in Nigeria

Background: Despite the reported increasing prevalence of diabetes mellitus, very few studies have documented report on oral health awareness and oral health conditions of individuals with diabetes mellitus from our environment. Thus this study aimed at assessing the oral health awareness, practices and status of individuals with diabetes mellitus attending a tertiary health facility in Nigeria.Methods: A cross sectional survey of 143 patients with diabetes attending the medical outpatients' clinic of the hospital. Information was obtained from participants using pretested structured questionnaires and oral examination. Tests of associations were determined using Chi-square and student t test.Results: One-fifth (20.3%) of the respondents were aware of good oral health preventing oral diseases in diabetes. Thirty-five (24.5%) knew that diabetes could worsen oral health condition and only 3 (2.1%) could correctly explain the association between diabetes and oral health conditions. Forty-three (30.1%) had participated in an oral health education program focused on diabetes and oral health. The majority (88.6%) had calculus accumulation while none had a healthy periodontium.Conclusion: Oral health awareness, practices and status of patients with diabetes were poor in our environment. Thus, these individuals need to be better informed of the relationship between oral health and diabetes.Keywords: Oral disease; diabetes; awareness; oral health educatio

Hemangiomatous ameloblastoma: report of a case

Hemangiomatous ameloblastoma is a rare variant of ameloblastoma with only a few cases reported in the English literature. This is a report of a 42 year old man with a recurrent mandibular neoplasm who had r epeated surgical interventions. Clinical and radiographic examinations were not significantly different from other regular variants of ameloblastoma. Microscopic examination however revealed islands of cuboidal and columnar cells arranged in a pallisaded pattern with a central area of squamous metaplasia and stellate reticulum-like cells. There were multiple vascular channels containing red blood cells within the stellate reticulum-like areas. Surgical resection of the mandibular mass was done with immediate reconstruction. It may be concluded that repeated surgical interventions may be a possible etiology for the development of hemangiomatous ameleblastoma

Process simulation and analysis of carbon capture with an aqueous mixture of ionic liquid and monoethanolamine solvent

This study investigated the prospect of using aqueous mixture of 1-butylpyridinium tetrafluoroborate ([Bpy][BF4]) ionic liquid (IL) and monoethanolamine (MEA) as solvent in post-combustion CO2 capture (PCC) process. This is done by analysis of the process through modelling and simulation. In literature, reported PCC models with a mixture of IL and MEA solvent were developed using equilibrium-based mass transfer approach. In contrast, the model in this study is developed using rate-based mass transfer approach in Aspen Plus®. From the results, the mixed aqueous solvent with 5–30 wt% IL and 30 wt% MEA showed 7%–9% and 12%–27% less specific regeneration energy and solvent circulation rate respectively compared to commonly used 30 wt% MEA solvent. It is concluded that the IL concentration (wt%) in the solvent blend have significant impact on specific regeneration energy and solvent circulation rate. This study is a starting point for further research on technical and economic analysis of PCC process with aqueous blend of IL and MEA as solvent

Trends of oral cancer in University College Hospital, Ibadan, Nigeria

Objective: The aim of this study was to describe the trend and recent pattern of oral cancer in the University College Hospital, Ibadan, Nigeria. Method: A retrospective analysis of all cases of oral cancer (excluding lymphoid cancers) documented in the records of the Departments of Oral and Maxillofacial Surgery and Pathology, University College Hospital (UCH), Ibadan, from the year 1983 to 2007 was done. The analysis of the data collected was compared with three earlier studies in this same centre and the published literature in general. Result: Over the 25-year-period a total 450 cases of oral cancer were recorded. More than half of the cases were squamous cell carcinomas (SCC) and 58.0% of these occurred in the palate which was the commonest site. Compared with previous studies, the male to female ratio of 1.4:1 revealed a higher number of females, and more patients were recorded in the first and tenth decades of life. Conclusion: The trends in oral cancer prevalence in UCH, Ibadan, show that oral SCC, still occurs commonly in the palate in our environment, and constituted the bulk of oral cancer. In addition, more females and patients within the extremes of age are being increasingly affected. There is before a need for more investigations into the possible aetiological factors in our environment in order to offer a preventive approach to the management of the disease

Linear acenes linked thiophene, electronic and chemical properties: Prospects for molecular organic electronic material

We report a theoretical study of linear acene (n=1 to 7) linked thiophene properties functionality. The total ground state and band gap energies, Coulomb potential and nuclear repulsion energy are calculated by DFT, MP2 at B3LYP exchange level of the theory and 6-311G* basis set. The results are in good agreement with the experimental and theoretical values. It is found that the total ground state energy of the system and band gap energy decreases with an increasing number of electrons in the rings. The addition of thiophene molecules tends to improve the electronic and chemical properties of the linear acenes, the material exhibit potential application in the organic molecular electronic material

Serum calcium levels of premenopausal, perimenopausal and postmenopausal rural women of Zuturung District, Kaduna State, Nigeria.

Background: Changes in sex hormones during the menopause transition period have an impact on calcium homeostasis. We studied the age at menopause, anthropometric and mean serum calcium levels in a cohort of premenopausal, perimenopausal and postmenopausal women in Zuturung, Kaduna state, Nigeria. Methods:135 subjects participated in the crossectional study. They comprised of 38 premenopausal, 22 perimenopausal and 75 postmenopausal subjects. After administering a questionnaire, the height (m), weight (g), and waist circumference (cm) of the subjects were determined using standard methods while the body mass index (BMI, kg/m2) was calculated. 5 milliliters of blood were collected via venipuncture and serum calcium level was determined by utilizing standard laboratory methods. Results:The results showed a mean and median age at menopause of 44.23±2.74 years and 44 years, respectively. Postmenopausal and perimenopausal subjects were more likely to be overweight with mean BMI 26.07±5.99 kg/m2and 26.42±7.27kg/m2 respectively, compared with their premenopausal counterparts with BMI of 25.18±3.48kg/m2 (p<0.001). The postmenopausal and perimenopausal subjects also had a longer waist circumference of 89.63±10.66cm and 92.19±11.91cm respectively compared with the premenopausal women 83.73±8.00cm (p<0.001). Only 73.86% of the postmenopausal women had a BMI ≥25kg/m2 whereas the prevalence of central obesity as determined using the waist circumference among the postmenopausal subjects was 79%. Mean serum calcium levels were slightly lower amongst both postmenopausal and perimenopausal subjects, 2.30±0.35mg/dl and 2.36±0.13mg/dl respectively as compared with the premenopausal women 2.37±0.15mg/dl. These differences were not significant (p>0.05). Conclusion: These findings suggest a lower mean age at menopause, a higher BMI, a longer waist circumference for the postmenopausal subjects (which was significant) with lower mean serum calcium levels (that was not significant) as compared with their premenopausal subjects. We recommend calcium supplementation and screening of postmenopausal women for postmenopausal osteoporosis. Keywords: Body mass index, calcium, menopause, osteoporosis, waist circumference, Zuturung distric

Pyrethroid resistance in the Sudan Savannah Region in Nigeria: a study of the resistance profile and resistance mechanism of Anopheles populations from Hadejia Town in Jigawa State

Insecticide-based control measures are key strategies against malaria vectors, and pyrethroid is the only recommended class of insecticide for public health use. The work aimed at determining the pyrethroid resistance in Anopheline mosquitoes and the frequency of the knockdown resistance (kdr) gene determinant. Larval samples were collected from two sites in Hadejia Town, Jigawa State in April 2020 and November/December 2020, and reared to adulthood in Bayero University Kano Biochemistry's insectary. Samples were identified by morphological and molecular techniques. Three to five-day-old adult mosquitoes were exposed to standard concentrations of 0.75% permethrin and 0.05% deltamethrin according to WHO criteria. Kdr mutations were investigated using PCR. Results of morphological identification showed an abundance (100%) of the Anopheles gambiae complex. However, molecular identification showed varying percentages of An. gambiae s.s (15% and 35%), An. coluzzii (80% and 45%), and An. arabiensis (5% and 20%) each for agricultural and industrial sites, respectively. The result also revealed relatively higher KT50 and KT50 in the agricultural site and was relatively higher with permethrin based on the KT50. Higher insecticide resistance of Anopheles mosquitoes observed in the agricultural site suggests that the practice may affect resistance development. The frequency of negative (homozygous) L1014F kdr mutation genotype was 70% in the resistant (alive) mosquito population and 50% in the susceptible (dead) mosquito population. The frequency of kdr mutation for agricultural and industrial sites was 35% and 15%, respectively. This finding suggests that the kdr gene determinant may not be the only mechanism involved in the resistance of the Anopheline mosquito to pyrethroid

Environmental Effects of Processing Marine Clay in Olotu, Ondo State, Nigeria

In this work, analysis of the released gas from calcined marine clay and lime shell was investigated. Study of the emitted gas/air from the calcined clay and shell showed that average concentration of carbon dioxide (CO2: 20.09PPM and 8.12PPM) are below the maximum standard natural concentration 600PPM of carbon dioxide in fresh air and the recommended World Health Organization Threshold Limit Value (TLV) of 500PPM. Average carbon monoxide (CO) concentration (0.004PPM, 0.010PPM) and sulfur dioxide (SO2) concentration (0.002PPM are below the Nigeria Ambient Air Quality Standards (NAAQS) and World Health Organization (WHO) maximum limit of 10PPM-20PPM (for carbon monoxide) and 0.01PPM- 0.5PPM (for sulfur dioxide) for an 8-hourly time. It was established that the average concentration of C0, C02, and S02 is so low and so pose no threat to the environment based on the review of the existing regulation, standards and codes (WHO and NAAQSO). Keywords: Ambient, Testo 350XL- Analyzer, PPM- Part Per Million, calcinin

Dynamic behavior investigations and disturbance rejection predictive control of solvent-based post-combustion CO2 capture process

Increasing demand for flexible operation has posed significant challenges to the control system design of solvent-based post-combustion CO2 capture (PCC) process: 1) the capture system itself has very slow dynamics; 2) in the case of wide range of operation, dynamic behavior of the PCC process will change significantly at different operating points; and 3) the frequent variation of upstream flue gas flowrate will bring in strong disturbances to the capture system. For these reasons, this paper provides a comprehensive study on the dynamic characteristics of the PCC process. The system dynamics under different CO2 capture rates, re-boiler temperatures, and flue gas flow rates are analyzed and compared through step-response tests. Based on the in-depth understanding of the system behavior, a disturbance rejection predictive controller (DRPC) is proposed for the PCC process. The predictive controller can track the desired CO2 capture rate quickly and smoothly in a wide operating range while tightly maintaining the re-boiler temperature around the optimal value. Active disturbance rejection approach is used in the predictive control design to improve the control property in the presence of dynamic variations or disturbances. The measured disturbances, such as the flue gas flow rate, is considered as an additional input in the predictive model development, so that accurate model prediction and timely control adjustment can be made once the disturbance is detected. For unmeasured disturbances, including model mismatches, plant behavior variations, etc., a disturbance observer is designed to estimate the value of disturbances. The estimated signal is then used as a compensation to the predictive control signal to remove the influence of disturbances. Simulations on a monoethanolamine (MEA) based PCC system developed on gCCS demonstrates the excellent effect of the proposed controller