Thirty-two actinomycetes strains were isolated from sediment samples from 12 different sites at Lagos Lagoon and identified using standard physiological and biochemical procedures as well as 16S rDNA gene sequence analysis. Secondary metabolites were extracted from the strains and their anticancer activity on the K562 (Human acute myelocytic leukemia), HeLa (cervical carcinoma), AGS (Human gastric), MCF-7 (breast adenocarcinoma) and HL-60 (Human acute promyelocytic leukemia) cell lines was determined. The metabolic extracts exhibited cytotoxicity with IC 50 values ranging from 0.030 mg/mL to 4.4 mg/mL. The Streptomyces bingchenggensis ULS14 extract was cytotoxic against all the cell lines tested. The bioactivity-guided extraction and purification of the metabolic extracts from this strain yielded two purified anticancer compounds: ULDF4 and ULDF5. The structures of the extracted compounds were determined using spectroscopic analyses, including electrospray ionization mass spectrophotometer and nuclear magnetic resonance (1 Dimensional and 2 Dimensional), and were shown to be structurally similar to staurosporine and kigamicin. The IC 50 of ULDF4 and ULDF5 against the HeLa cell line was 0.034 μg/mL and 0.075 μg/mL, respectively. This study is the first to reveal the anticancer potential of actinomycetes from Lagos Lagoon, which could be exploited for therapeutic purposes.
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Multi-drug (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) continues to be a global public health problem especially in high TB burden countries like Nigeria. Many of these cases are undetected and go on to infect high risk individuals. Clinical samples from positive rifampicin resistant Xpert®MTB/Rif assay were subjected to direct whole genome sequencing and bioinformatics analysis to identify the full antibiotics resistance and lineage profile. We report two (2) XDR TB samples also belonging to the East-Asian/Beijing family of lineage 2 Mycobacterium tuberculosis complex from clinical samples in Nigeria. Our findings further reveal the presence of mutations that confer resistance to first-line drugs (rifampicin, isoniazid, ethambutol and pyrazanimide), second-line injectables (capreomycin, streptomycin, kanamycin and/or amikacin) and at least one of the fluoroquinolones (ofloxacin, moxifloxacin, levofloxacin and/or ciprofloxacin) in both samples. The genomic sequence data from this study not only provide the first evidence of XDR TB in Nigeria and West Africa, but also emphasize the importance of WGS in accurately detecting MDR and XDR TB, to ensure adequate and proper management treatment regimens for affected individuals. This will greatly aid in preventing the spread of drug resistance TB in high burden countries.
Background A common complication of any respiratory disease by a virus could be a secondary bacterial infection, which is known to cause an increase in severity. It is, however, not clear whether the presence of some opportunistic pathogens called pathobionts contributes to the severity of the disease. In COVID-19 patients, undetected bacterial co-infections may be associated with the severity of the disease. Therefore, we investigated the implications of bacterial co-infections in COVID-19 cases. Results This is a cross-sectional study that involved archived specimens collected from nasopharyngeal samples of 150 people for COVID-19 screening in Lagos. DNA extraction from the samples was carried out to determine the presence of five respiratory bacterial pathogens using nested real-time PCR, and data were analysed using the Chi-square test. Of the 150 samples collected, 121 (80.7%) were positive for SARs-CoV-2 infection and 29 were negative. The proportion of patients with bacteria co-infection in COVID-19-negative, asymptomatic, and mild cases were 93.1%, 70.7%, and 67.5%, respectively. There was no statistically significant difference between mild COVID-19 conditions and bacteria co-infection (p = 0.097). There was also no significant difference in the nasal carriage of Staphylococcus aureus, Mycoplasma pneumoniae, and Haemophilus spp. However, there was a statistically significant increase in the carriage of Moraxella catarrhalis and Chlamydophila pneumoniae among COVID-19-negative patients when compared with the positive patients (p value = 0.003 and 0.000 for Moraxella catarrhalis and Chlamydophila pneumoniae, respectively). Conclusions The current study shows that bacterial co-infection and superinfection with COVID-19 are not associated with mild and asymptomatic COVID-19 cases in our setting. However, given the high prevalence of Staphylococcus aureus and Mycoplasma pneumoniae among the mild COVID-19 cases seen in this study, early diagnosis and treatment of these bacterial co-infections are still encouraged to mitigate the effect on the severity of COVID-19.
Multi-drug (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) continues to be a global public health problem especially in high TB burden countries like Nigeria. Many of these cases are undetected and go on to infect high risk individuals. Clinical samples from positive rifampicin resistant Xpert®MTB/Rif assay were subjected to direct whole genome sequencing and bioinformatics analysis to identify the full antibiotics resistance and lineage profile. We report two (2) XDR TB samples also belonging to the East-Asian/Beijing family of lineage 2 Mycobacterium tuberculosis complex (MTBC) from clinical samples in Nigeria. Our findings further reveal the presence of resistance genes to first-line drugs (rifampicin, isoniazid, ethambutol and pyrazanimide), second-line injectables (capreomycin, streptomycin, kanamycin and/or amikacin) and at least one of the fluoroquinolones (ofloxacin, moxifloxacin, levofloxacin and/or ciprofloxacin) in both samples. The genomic sequence data from this study not only provide the first evidence of XDR TB in Nigeria and West Africa, but also emphasize the importance of WGS in accurately detecting MDR and XDR TB, to ensure adequate and proper management treatment regimens for affected individuals. This will greatly aid in preventing the spread of drug resistance TB in high burden countries.
Objective The study examined whether the benefit and adverse effects of the tenofovir-based highly active antiretroviral therapy (HAART) regimen outweigh the non-tenofovir-based regimen in the elderly population. Methods We searched PubMed, EMBASE, Cochrane Central Library, Google Scholar, and some hand searches to identify eligible studies. Only randomized control trials on elderly HIV-positive patients on Tenofovir-based regimens living in sub-Saharan Africa were included. Studies on pregnant women or prophylactic tenofovir were excluded. The primary outcomes are viral suppression, mortality, and anemia. Two reviewers independently selected the studies, extracted data, and assessed the risk of bias. We analyzed using risk ratio, with 95% confidence intervals. A fixed effect model along with an assessment of heterogeneity was done for meta-analysis. Results Four studies with a total of 263 participants were included. Our meta-analysis shows that there was no difference between participants on a tenofovir-based regimen and the non-tenofovir-based regimen in terms of viral suppression, mortality, anemia, and hypertension. Our meta-analysis shows that there was no difference between participants on tenofovir based regimen and non-tenofovir based regimen in terms of viral suppression (RR=1.96, 95% CI (1.42 -2.70; I2=0%, 4 trials, 263 participants, very low certainty of evidence), mortality (RR = 2.90, 95% CI (0.12 – 69.87, I2=Not estimated, a trial, 120 participants, very low certainty of evidence), anaemia (RR=1.61, 95% CI (1.02-2.90; I2 = 0.16, 2 trials, 154 participants, very low certainty of evidence), hypertension RR = 0.76, 95% CI (0.44-1.31) I2 = Not estimated, a trial, 34 participants, low-certainty of evidence). None of the trials reported the incidence of chronic kidney disease and bone demineralization. Conclusion There was very-low certainty evidence that no difference exists between the tenofovir-based HAART regimen and the non-tenofovir-based regimen in terms of benefits and short-term adverse outcomes. Well-designed randomized clinical trials are needed with a focus on long-term adverse effects.
Antimicrobial drug resistance has become a global challenge and one of utmost concern due to the global epidemiological infections. Medicinal plants have long performed an essential role in medicine and can be an essential source of recent antimicrobials and techniques for treating resistance. Clausena is a genus in the Rutaceae family which are widely recognized and utilized in traditional medicines. Many members of this genus have been a primary source of medications and drug history. The antimicrobial effectiveness of the secondary metabolites from the roots, stems, leaves, rhizomes, twigs, seeds, fruits, and flowers of several Clausena species has been widely examined and was found to be more effective against bacteria with Clausena anisata being the most promising specie. A total of 16 active compounds including 12 alkaloids, 2 coumarins, and 2 terpenoids were reported to be isolated from different parts of the plant species with mukonal being the only compound that shows dual potency both against fungi and protozoa. This review aims to sum up research advances made from 2000 to date, on the antibacterial, antifungal, and antiprotozoal activities of Clausena species, and highlight the potential use of Clausena plants in the prevention and treatment of infectious diseases.
Mutations in whiB7 have been associated with both hypersusceptibility and resistance to various antibiotics in Mycobacterium tuberculosis (Mtb). Unlocking the secrets of antibiotic resistance in the bacterium, we examined mutations in the coding sequences of whiB7 of over 40,000 diverse Mtb isolates. Our results unveil the dominant c.191delG (Gly64delG) mutation, present in all members of the lineage L1.2.2 and its impact on WhiB7's conserved GVWGG-motif, causing conformational changes and deletion of the C-terminal AT-hook. Excitingly, we discovered six unique mutations associated with partial or total deletion of the AT-hook, specific to certain sublineages. Our findings suggest the selective pressures driving these mutations, underlining the potential of genomics to advance our understanding of Mtb's antibiotic resistance. As tuberculosis remains a global health threat, our study offers valuable insights into the diverse nature and functional consequences of whiB7 mutations, paving the way for the development of novel therapeutic interventions.
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