Evaluation of microbial quality of selected blister-packed paracetamol tablets and paracetamol syrups marketed in Nigeria

Ten brands of blister-packed paracetamol tablet and twenty brands of paracetamol syrup marketed in Nigeria were evaluated for their microbial quality. While no microbial contaminant was isolated from all blistered-packed paracetamol tablets, ten of syrups were contaminated with organisms such as Escherichia coli, Klebsiellaspp, Pseudomonas aeruginosa and Staphylococcus aureus at 14.3, 21.4, 21.4 and 42.9% occurrence respectively. Penicilliumspp was isolated from two brands. Antibiotic susceptibility profile revealed all bacterial isolates to be multidrug resistant with Escherichia coli resistant to all antibiotics tested, while Staphylococcus aureus isolates were sensitive to Oxacillin, Cefuroxime and vancomycin. Pseudomonas aeruginosa isolates were sensitive to ofloxacin and gentamycin while Klebsiella isolates were sensitive to ofloxacin and nitrofurantoin. The study concluded that compliance with the provisions of good manufacturing practice as well as good quality control play role in determining the microbial bioburden of pharmaceutical products while isolation of multi-drug resistant organisms calls for establishment and adherence to antibiotics use policy in Nigeria.Keywords: Blister-pack, multidrug resistance, good manufacturing practice, quality control, bioburde

Collagen based magnetic nanocomposites for oil removal applications

A stable magnetic nanocomposite of collagen and superparamagnetic iron oxide nanoparticles (SPIONs) is prepared by a simple process utilizing protein wastes from leather industry. Molecular interaction between helical collagen fibers and spherical SPIONs is proven through calorimetric, microscopic and spectroscopic techniques. This nanocomposite exhibited selective oil absorption and magnetic tracking ability, allowing it to be used in oil removal applications. The environmental sustainability of the oil adsorbed nanobiocomposite is also demonstrated here through its conversion into a bi-functional graphitic nanocarbon material via heat treatment. The approach highlights new avenues for converting bio-wastes into useful nanomaterials in scalable and inexpensive ways

Novel functional insights into ischemic stroke biology provided by the first genome-wide association study of stroke in indigenous Africans

\ua9 The Author(s) 2024. Background: African ancestry populations have the highest burden of stroke worldwide, yet the genetic basis of stroke in these populations is obscure. The Stroke Investigative Research and Educational Network (SIREN) is a multicenter study involving 16 sites in West Africa. We conducted the first-ever genome-wide association study (GWAS) of stroke in indigenous Africans. Methods: Cases were consecutively recruited consenting adults (aged > 18 years) with neuroimaging-confirmed ischemic stroke. Stroke-free controls were ascertained using a locally validated Questionnaire for Verifying Stroke-Free Status. DNA genotyping with the H3Africa array was performed, and following initial quality control, GWAS datasets were imputed into the NIH Trans-Omics for Precision Medicine (TOPMed) release2 from BioData Catalyst. Furthermore, we performed fine-mapping, trans-ethnic meta-analysis, and in silico functional characterization to identify likely causal variants with a functional interpretation. Results: We observed genome-wide significant (P-value < 5.0E−8) SNPs associations near AADACL2 and miRNA (MIR5186) genes in chromosome 3 after adjusting for hypertension, diabetes, dyslipidemia, and cardiac status in the base model as covariates. SNPs near the miRNA (MIR4458) gene in chromosome 5 were also associated with stroke (P-value < 1.0E−6). The putative genes near AADACL2, MIR5186, and MIR4458 genes were protective and novel. SNPs associations with stroke in chromosome 2 were more than 77 kb from the closest gene LINC01854 and SNPs in chromosome 7 were more than 116 kb to the closest gene LINC01446 (P-value < 1.0E−6). In addition, we observed SNPs in genes STXBP5-AS1 (chromosome 6), GALTN9 (chromosome 12), FANCA (chromosome 16), and DLGAP1 (chromosome 18) (P-value < 1.0E−6). Both genomic regions near genes AADACL2 and MIR4458 remained significant following fine mapping. Conclusions: Our findings identify potential roles of regulatory miRNA, intergenic non-coding DNA, and intronic non-coding RNA in the biology of ischemic stroke. These findings reveal new molecular targets that promise to help close the current gaps in accurate African ancestry-based genetic stroke’s risk prediction and development of new targeted interventions to prevent or treat stroke

Preparation of cellulose nanofibers with hydrophobic surface characteristics.

The aim of this study was to develop cellulose nanofibers with hydrophobic surface characteristics using chemical modification. Kenaf fibers were modified using acetic anhydride and cellulose nanofibers were isolated from the acetylated kenaf using mechanical isolation methods. Fourier transform infrared spectroscopy (FTIR) indicated acetylation of the hydroxyl groups of cellulose. The study of the dispersion demonstrated that acetylated cellulose nanofibers formed stable, well-dispersed suspensions in both acetone and ethanol. The contact angle measurements showed that the surface characteristics of nanofibers were changed from hydrophilic to more hydrophobic when acetylated. The microscopy study showed that the acetylation caused a swelling of the kenaf fiber cell wall and that the diameters of isolated nanofibers were between 5 and 50 nm. X-ray analysis showed that the acetylation process reduced the crystallinity of the fibers, whereas mechanical isolation increased it. The method used provides a novel processing route for producing cellulose nanofibers with hydrophobic surfaces

Stroke genetics informs drug discovery and risk prediction across ancestries

Previous genome-wide association studies (GWASs) of stroke — the second leading cause of death worldwide — were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries

The electrical conductance and viscosity of Nigerian traditional soaps in alcoholic media

The electrical conductances and viscosities of Nigerian traditional soaps in alcohols have been measured. Potassium, sodium and potassium/sodium (50:1) soaps have been prepared from palm kernel oils using laboratory prepared reagent alkalis and their conductances have also been measured. While the conductances vary with the degree of purity of the soaps and the polarity of the solvents, the activation energy for conductance only varies with the change of solvents. The conductances of the laboratory prepared potassium soaps are higher than those of the sodium soaps, suggesting the metal ions to be the main charge carriers in solution. Plots of logarithm of conductivity against inverse temperature are linear for all the soaps in methanol and ethanol while such plots are non-linear in propan-1-ol in which the soaps are least soluble with lowest conductance values. However, the plot is linear for the laboratory prepared potassium soap in propan-l-ol. The conductivities of the commercial (traditionally prepared) soaps are found to be higher than those of the laboratory prepared ones, indicating the formation of soaps of many fatty acid constituents of palm kernel oil in the traditional process of soap preparation. The variations of the viscosities of the solutions with concentration, temperature and carbon chain length of the solvents are also discussed. The plots of log(10) eta versus 1/T for all the soap solutions are linear suggesting that the solutions are non-associated liquid systems in agreement with the conductance data. The variations of the activation energies obtained from these plots with concentration and molecular weights of the solvents are discussed. The viscosity data are also interpreted on the basis of Jones-Dole equation. The trend of the B-coefficient of this equation suggests that the soaps become less ideal with increase in the molecular weights of the alcohols. The erratic nature of the A-coefficient values is again related to the results of conductance measurement which indicate that the traditional method of soap preparation produces mixed soaps and that the soaps contain many trace metal ions. (C) 2001 Elsevier Science B.V. All rights reserved

ESR study of alkyl radicals adsorbed on porous Vycor glass I. Build-up of methyl and ethyl radicals

Methyl and ethyl radicals have been produced on the surface of porous Vycor glass (PVG) at 77 K by UV photolysis of adsorbed azomethane and azoethane. respectively. The build-up of the radicals as a function of irradiation time has been studied by using the technique of electron spin resonance (ESR). Ethyl radicals are found to be slightly more difficult to generate than methyl radicals and both radicals were observed not to approach saturation within the period of irradiation employed. The variation of the rate of formation of the radicals with surface coverage and their formation during re-irradiation after previous decay for several hours at 77 K are discussed. (C) 2001 Elsevier Science B.V. All rights reserved

The methylation of benzene with methane over zeolite catalysts: effect of hydrocarbon impurities

Trace amounts of ethylene impurities in the methane used for benzene methylation over ZSM-5 and H-beta catalysts are found to enhance benzene conversions and selectivity to ethylbenzene. However, methane containing ethane impurities yielded negligible benzene conversion in the absence of oxygen over CoZSM-5 while a much higher conversion is obtained over H-beta due to cracking of benzene as previously reported

Raman spectroscopic investigation of acetylation of raw cotton

Raman spectroscopy has been used to investigate raw cotton acetylation using acetic anhydride/4-dimethylaminopyridine (DMAP) catalyst blend without solvent. The Raman data further confirm successful acetylation as shown by FTIR that was demonstrated previously to be highly sensitive for determining the level of acetylation. However, the Raman peaks are much weaker than the FTIR bands. Nevertheless, the variations of the extent of acetylation estimated from both Raman and FTIR spectra with weight percent gain due to acetylation (WPG) were observed to follow the same pattern. The degrees of acetylation calculated from Raman data were also found to increase linearly with that calculated from the more sensitive FTIR technique. Raman technique is thus suitable for further development as an analytical tool for determining the acetylation level of natural cellulose fibres. Raman data have also shown that the acetylation reaction reduces the crystallinity of cotton. (c) 2005 Elsevier B.V. All rights reserved