Prevalence of non-tuberculous mycobacteria among previously treated TB patients in the Gulf of Guinea, Africa.

Objective: Differentiation between non-tuberculous mycobacteria (NTM) and Mycobacterium tuberculosis complex (MTBC) is crucial for case management with the appropriate antimycobacterials. This study was undertaken in three West and Central African countries to understand NTM associated with pulmonary tuberculosis in the sub-region. Methods: A collection of 503 isolates (158 from Cameroon, 202 from Nigeria and 143 from Ghana) obtained from solid and liquid cultures were analysed. The isolates were tested for drug susceptibility, and MTBC were confirmed using IS6110. All IS6110-negative isolates were identified by 65-kilodalton heat shock protein (hsp65) gene amplification, DNA sequencing and BLAST analysis. Results: Overall, the prevalence of NTM was 16/503 (3.2%), distributed as 2/202 (1%) in Nigeria, 2/158 (1.3%) in Cameroon and 12/143 (8.4%) in Ghana. The main NTM isolates included 5/16 (31.3%) M. fortuitum, 2/16 (12.5%) M. intracellulare and 2/16 (12.5%) M. engbaekii. Eight (57.1%) of the 14 previously treated patients harboured NTM (odds ratio 0.21, 95% confidence interval 0.06-0.77; P=0.021). Three multi-drug-resistant strains were identified: M. engbaekii, M. fortuitum and M. intracellulare. Conclusion: NTM were mainly found among individuals with unsuccessful treatment. This highlights the need for mycobacterial species differentiation using rapid molecular tools for appropriate case management, as most are resistant to routine first-line antimycobacterials.

Datasets on process transesterification of binary blend of oil for fatty acid ethyl ester (FAEE) synthesized via the ethanolysis of heterogeneous doped catalyst.

The data employed the blend of waste used oil and beef tallow for the synthesis of fatty acid ethyl ester (FAEE) via ethanolysis of developed catalyst from calcined fermented cocoa pod husk powder (CFCPHP) doped with burnt cocoa pod husk powder (BCHP). Characterization of the developed doped catalyst (DDC) was carried out using FTIR, SEM, XRD, and BET adsorption analysis, while the basic strength of the DDC was tested through reusability test data. Mathematical optimization of the process condition was carried out through Box-Behnken Experimental Design (BBED) in 29 runs with variations in four variables as catalyst concentration (1.5 to 3.5 wt.%), reaction time (60 to 100 min), ethanol/oil molar ratio (EtOH/OMR) of 3 to 7, and reaction temperature (60 to 80 °C). The FAEE quality was ascertained by determining its fuel properties. The data showed that the binary blend ratio of 42:58 of Waste Used oil: Beef Tallow oil (WUO: BTO) was obtained through API gravity ratio formulation. The developed doped catalyst (DDC) produced a high CaO-base of 84.30 (wt.%), with a high total basic site of 210 µmole.g-1 via BET and XRD analysis. The SEM analysis dataset showed non-uniform sizes, highly porous and crystalline sample, while the dataset on FTIR analysis data confirmed the presence of wagging and twisting CO3 2-, the bending vibration of O-Ca-O, the sp2 of C = O, C = C, the sp of C  ≡  C and C  ≡  N, the bending structure of O-H, and the O=O, N ≡ O of Amines, and Amides. Based on the experiment, the maximum experimental yield of 97.80 (%wt.) at runs 7, and low yield of 89.50 (%wt.) at run 17 was obtained for FAEE. Mathematical optimization in 10 solutions predicted the FAEE yield of 97.7999 (%wt.) at the catalyst concentration of 3.10 (wt.%), the reaction time of 68.09 min, the EtOH/OMR of 3.01, and the reaction temperature of 72.21 °C. This data was validated in replicate, and the average mean value of FAEE was 97.68 (%wt.). Dataset on ANOVA and parametric analysis showed that the variable factors considered were significant at p-value <0.0001, with high R2 of 99.14%, R2-predicted of 98.32%, R2-adjusted of 98.28%, and adequate precision of 51.152, respectively. Catalyst reusability test data showed that the cycle number was stopped at the 5th cycle due to the decrease in catalyst basic strength. The produced FAEE dataset was within the recommended standard, and the data showed the developed doped catalyst successfully converted binary blend oil to FAEE, and the fermentation process increased the CaO-based conversion of DDC.

Data on the derived mesoporous based catalyst for the synthesized of fatty acid methyl ester (FAME) from ternary oil blend: An optimization approach.

This work presents datasets on fatty acid methyl ester (FAME) synthesized from the ternary blend of Cucurbita pepo-chrysophyllum albidum -papaya mix oils via methanolysis of mesoporous CaO heterogeneous catalyst derived from the mixture of Citrullus lanatus and Musa acuminate peels. The oils were extracted from the milled powdered using the solvent extraction method. Ternary oil mixed ratio of 33:33:34 with low acid value and density was achieved using simplex lattice design software. Characterization of the mixed calcined catalyst powder (MCCP) at 700 °C for 4 h was carried out using scanning electron microscopy (SEM), energy dispersive spectroscope (EDS), X-ray diffraction analysis (XRD), and BET analysis. The thermal decomposition of mixed calcined catalyst powder (MCCP) produced 78.74% CaO with a strong basic site of 143 (µmole.g-1). Fatty acid methyl ester (FAME) was synthesized through the based catalyst transesterification of a derived catalyst by considering four variables data (reaction time, reaction temperature, catalyst amount and methanol/oil molar ratio) using response surface methodology (RSM). The maximum experimental FAME data of 94.29 (wt. %) was achieved at run 16, but the central composite design (CCD) software predicted value of 98.00 (wt. %) at a reaction time of 70 min, reaction temperature of 80 °C, catalyst amount of 5.0 (wt.) and methanol to oil molar ratio (MeOH/OMR) of 6.97, at the desirability of 97.90%. This was validated in triplicate, and the average FAME data obtained was 93.45 (wt. %). The produced FAME properties dataset meets the standard recommended value of ASTM and EN14214.

Molecular epidemiology of Mycobacterium bovis in Cameroon.

We describe the largest molecular epidemiological study of Bovine Tuberculosis (bTB) in a sub-Saharan African country with higher spatial resolution providing new insights into bTB. Four hundred and ninety-nine samples were collected for culture from 201 and 179 cattle with and without bTB-like lesions respectively out of 2,346 cattle slaughtered at Bamenda, Ngaoundere, Garoua and Maroua abattoirs between 2012-2013. Two hundred and fifty-five M. bovis were isolated, identified and genotyped using deletion analysis, Hain® Genotype MTBC, spoligotyping and MIRU-VNTR. African 1 was the dominant M. bovis clonal complex, with 97 unique genotypes including 19 novel spoligotypes representing the highest M. bovis genetic diversity observed in Africa to date. SB0944 and SB0953 dominated (63%) the observed spoligotypes. A third of animals with multiple lesions had multiple strain infections. Higher diversity but little evidence of recent transmission of M. bovis was more common in Adamawa compared to the North-West Region. The Adamawa was characterised by a high frequency of singletons possibly due to constant additions from an active livestock movement network compared to the North-West Region where a local expansion was more evident. The latter combined with population-based inferences suggest an unstable and stable bTB-endemic status in the North-West and Adamawa Regions respectively.

Abattoir-based estimates of mycobacterial infections in Cameroon.

Mycobacteria cause major diseases including human tuberculosis, bovine tuberculosis and Johne's disease. In livestock, the dominant species is M. bovis causing bovine tuberculosis (bTB), a disease of global zoonotic importance. In this study, we estimated the prevalence of Mycobacteria in slaughter cattle in Cameroon. A total of 2,346 cattle were examined in a cross-sectional study at four abattoirs in Cameroon. Up to three lesions per animal were collected for further study and a retropharyngeal lymph node was collected from a random sample of non-lesioned animals. Samples were cultured on Lowenstein Jensen media and the BACTEC MGIT 960 system, and identified using the Hain® Genotype kits. A total of 207/2,346 cattle were identified with bTB-like lesions, representing 4.0% (45/1,129), 11.3% (106/935), 23.8% (38/160) and 14.8% (18/122) of the cattle in the Bamenda, Ngaoundere, Garoua and Maroua abattoirs respectively. The minimum estimated prevalence of M. bovis was 2.8% (1.9-3.9), 7.7% (6.1-9.6), 21.3% (15.2-28.4) and 13.1% (7.7-20.4) in the four abattoirs respectively. One M. tuberculosis and three M. bovis strains were recovered from non-lesioned animals. The high prevalence of M. bovis is of public health concern and limits the potential control options in this setting without a viable vaccine as an alternative.

Quinolone accumulation by Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli.

The accumulation of nalidixic acid and 14 fluoroquinolones over a range of external drug concentrations (10-100 mg/L; c. 25-231 microM) into intact cells of Escherichia coli KL-16, Staphylococcus aureus NCTC 8532, Pseudomonas aeruginosa NCTC 10662 and spheroplasts of E. coli was investigated. The effect of 100 microM carbonyl cyanide m-chlorophenyl hydrazone (CCCP) upon the concentration of quinolone accumulated by intact cells and spheroplasts of E. coli was also determined. Except for pefloxacin, there was an increase in the concentration of the six quinolones examined accumulated by E. coli, despite a reduction in fluorescence at alkaline pH. For ciprofloxacin the partition coefficient (P(app)) was constant despite an increase in the pH; however, the P(app) for nalidixic acid decreased significantly with an increase in pH. The concentration of nalidixic acid, ciprofloxacin and enrofloxacin accumulated by E. coli and S. aureus increased with an increase in temperature up to 40 degrees C and 50 degrees C, respectively. Above these temperatures the cell viability decreased. With an increase in drug concentration there was, for intact E. coli and 12/15 agents, and for S. aureus and 10/15 agents, a linear increase in the concentration of drug accumulated. However, for P. aeruginosa and 13/15 agents there was apparent saturation of an accumulation pathway. Assuming 100% accumulation into intact cells of E. coli, for 10/14 fluoroquinolones < or = 40% was accumulated by spheroplasts. CCCP increased the concentration of quinolone accumulated but the increase varied with the agent and the bacterial species. The variation in the effect of CCCP upon accumulation of the different quinolones into E. coli could result from chemical interactions or from different affinities of the proposed efflux transporter for each quinolone. Overall, these data suggest that accumulation of most quinolones into E. coli and S. aureus proceeds by simple diffusion, but that P. aeruginosa behaves differently.

Accumulation and killing kinetics of fifteen quinolones for Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa.

The accumulation of fifteen quinolone antimicrobial agents (nalidixic acid, eight mono-fluorinated agents, three di-fluorinated agents and three tri-fluorinated agents) by Escherichia coli KL16, Staphylococcus aureus NCTC 8532 and Pseudomonas aeruginosa NCTC 10662 was studied. The concentration of quinolones accumulated varied with the quinolone and the bacterial species, and was not affected by the number of fluorine atoms on the quinolone nucleus. There was also no direct relationship between the hydrophobicity or the molecular size of each drug and accumulation or activity. The killing of the three strains by the fifteen quinolones at a concentration of 10 mg/L was determined in broth and phosphate buffer to mimic the conditions of the accumulation assay. The bactericidal activity varied with the agent and the strain, and usually reflected the in-vitro activity of the drug. Despite most agents causing a decrease in the viable count of the three strains there was no detectable effect on the pattern of accumulation of the quinolones.