Helicobacter pylori strains from a Nigerian cohort show divergent antibiotic resistance rates and a uniform pathogenicity profile

Antibiotic resistance in Helicobacter pylori is a factor preventing its successful eradication. Particularly in developing countries, resistance against commonly used antibiotics is widespread. Here, we present an epidemiological study from Nigeria with 111 isolates. We analyzed the associated disease outcome, and performed a detailed characterization of these isolated strains with respect to their antibiotic susceptibility and their virulence characteristics. Furthermore, statistical analysis was performed on microbiological data as well as patient information and the results of the gastroenterological examination. We found that the variability concerning the production of virulence factors between strains was minimal, with 96.4% of isolates being CagA-positive and 92.8% producing detectable VacA levels. In addition, high frequency of bacterial resistance was observed for metronidazole (99.1%), followed by amoxicillin (33.3%), clarithromycin (14.4%) and tetracycline (4.5%). In conclusion, this study indicated that the infection rate of H. pylori infection within the cohort in the present study was surprisingly low (36.6%). Furthermore, an average gastric pathology was observed by histological grading and bacterial isolates showed a uniform pathogenicity profile while indicating divergent antibiotic resistance rates

Application of some selected yeasts isolates in bioelectricity generation using Microbial Fuel Cell (MFC)

Power supply has remained a challeng issue in developing coutries. The aim of this study was to evaluate the potentials of selected yeast species for bioelectricity generation. Different yeast species were isolated from cassava wastewater, whey wastewater, human urine, and rabbit dung using the spread plate method. These isolates were identified using analytical profile index (API). Results obtained revealed the identity of the isolated yeast species as Candida famata, Candida hellenical. Candida tropicalis and Saccharomyces cerevisia (using API method).The isolated yeast species were used singly, and as a consortium for bioelectricity generation, and yeast in continuous mode. The same wastes as used for the isolation process were evaluated as possible substrates for the generation of bioelectricity. Out of the four wastes used, cassava processing wastewater gave the  highest bioelectricity potential and was subsequently used as substrate for further study. Saccharomyces cerevisiae elicited the highest electricity generation when the four yeast species were used singly (1.08V). A consortium of the four isolates elicited a synergis effect, generating 1.57V of voltage. Stacking of the Microbial Fuel Cell(MFC) components improved voltage to 2.4V due to its lower internal resistance within the stacked materials. It is apparent from the results obtained in this study that when properly harnessed, microbial fuel cells (MFCs) technology could serve as alternate source of renewable energy. Keywords: Microbial fuel cells, Waste, yeasts, Salt- Bridge, Nafion117

Prevalence of Tinea Capitis among Children in Osogbo, Nigeria, and the Associated Risk Factors

Tinea capitis is a fungi infection of the scalp that disproportionately affects children in rural and underserved communities in Nigeria. A case-control study was conducted to identify the causative agents and factors that predispose school pupils to tinea capitis in two selected government-owned public primary schools in Osogbo, Southwestern Nigeria. A total of 230 participants were included in the study: 115 cases and 115 controls. Head scrapings were collected from pupils with suspected T. capitis lesions, viewed under Potassium Hydroxide smear microscopy and cultured in Sabouraud’s Dextrose Agar (SDA) for characteristic fungal elements. A total of 105 (91%) samples were successfully cultured, of which 56% (59/105) were from male pupils. Tricophyton rubrum (34%), Tricophyton mentagrophyte (31%) and Microsporum canis (18%) were the most prevalent organisms. Other dermatophytes obtained include Microsporum nanuum (3%), Epidermophyton floccusum (6%), Tricophyton verucosum (1%), and Microsporum gypseum (8%). Pupils between the ages of 4 and 7 years had the highest distribution (67%) followed by those between the ages of 8 and 11 years (39%). Playing with animals, the sharing of combs and not bathing with soap were significantly associated with tinea capitis infection (P < 0.05) in each case. This study showed a high prevalence of tinea capitis caused by the identified dermatophytes in the area

Characterization of <i>H</i>. <i>pylori</i> isolates.

<p>111 isolated strains were characterized by the status of resistance, the analysis of the major virulence factors as well as their IL-8 expression. A: The bacterial resistance to amoxicillin, clarithromycin, metronidazole and tetracycline is shown as percentage. These results are based on MIC tests. B. <u>Black:</u> shows PCR results of the genes <i>cagA</i> and <i>vacA</i>. <u>Grey:</u> shows the Western blotting results of the proteins CagA, translocation of CagA into AGS cells, and VacA. C. Induction of IL-8 secretion by AGS cells in relation to <i>H</i>. <i>pylori</i> P12. Each dot illustrates one isolate. <u>Black:</u> isolates produce VacA, CagA, and are also able to translocate CagA. <u>Green:</u> isolates which produce neither VacA nor CagA and show no CagA translocation. <u>Red:</u> isolates which do produce VacA, but not CagA. <u>Blue:</u> isolates which produce and translocate CagA, but do not produce VacA. <u>Purple:</u> isolates which produce VacA and CagA, but are not able to translocate CagA.</p

Primer sequences.

<p>Primer sequences.</p

EPIYA motifs.

<p>EPIYA region sequences of 14 isolates including reference strains (196A, 26695, ATCC43526, and P12) are shown (red). 9 isolates show the KDKGPE motif (blue) in front of the EPIYA-A motif [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0176454#pone.0176454.ref028" target="_blank">28</a>].</p

Pathology analyzed by a histological grading (based on the updated Sydney System (22)) in HE stained slides.

<p>Pathology analyzed by a histological grading (based on the updated Sydney System (22)) in HE stained slides.</p