Evaluation of efflux pump activity and biofilm formation in multidrug resistant clinical isolates of Pseudomonas aeruginosa isolated from a Federal Medical Center in Nigeria.

BACKGROUND: Pseudomonas aeruginosa an opportunistic pathogen, is widely associated with nosocomial infections and exhibits resistance to multiple classes of antibiotics. The aim of this study was to determine the antibiotic resistance profile, biofilm formation and efflux pump activity of Pseudomonas strains isolated from clinical samples in Abeokuta Ogun state Nigeria. METHODS: Fifty suspected Pseudomonas isolates were characterized by standard biochemical tests and PCR using Pseudomonas species -specific primers. Antibiotic susceptibility testing was done by the disc diffusion method. Efflux pump activity screening was done by the ethidium bromide method and biofilm formation assay by the tissue plate method. Genes encoding biofilm formation (pslA & plsD) and efflux pump activity (mexA, mexB and oprM) were assayed by PCR. RESULTS: Thirty-nine Pseudomonas spp. were identified of which 35 were Pseudomonas aeruginosa and 4 Pseudomonas spp. All 39 (100%) Pseudomonas isolates were resistant to ceftazidime, cefuroxime and amoxicillin-clavulanate. Thirty-six (92%), 10(25.6%), 20 (51.2%), 11(28%) and 9(23%) of the isolates were resistant to nitrofurantoin, imipenem, gentamicin, cefepime and aztreonam respectively. All the isolates had the ability to form biofilm and 11 (28%) of them were strong biofilm formers. They all (100%) harboured the pslA and pslD biofilm encoding genes. Varied relationships between biofilm formation and resistance to ciprofloxacin, ofloxacin, cefixime, gentamicin, imipenem, and aztreonam were observed. Only 23(59%) of the Pseudomonas isolates phenotypically exhibited efflux pump activity but mexA gene was detected in all 39 (100%) isolates while mexB and oprM genes were detected in 91%, 92%, and 88% of strong, moderate and weak biofilm formers respectively. CONCLUSION: Multidrug resistance, biofilm and efflux pump capabilities in Pseudomonas aeruginosa have serious public health implications in the management of infections caused by this organism.

Water, sanitation, and hygiene (WASH) facilities and infection control/prevention practices in traditional birth homes in Southwest Nigeria.

BACKGROUND: Poor environmental conditions and hygiene practices at the time of childbirth is linked to life-threatening infections and death in mothers and babies. Improvements in water, sanitation, and hygiene (WASH) have been identified as a means through which the lives of mothers and babies could be saved. This study was carried out to explore WASH conditions and infection prevention and control (IPC) practices in traditional birth homes/centers in Abeokuta, Southwest Nigeria. A total of 50 traditional birth centers and attendants (TBAs) were enrolled in the study. Sociodemographic characteristics of the TBAs and features of the birth centers were obtained using a semi-structured questionnaire. Assessment of WASH conditions and IPC practices was based on established protocols. RESULTS: Findings revealed that majority of the centers operated under poor WASH conditions and IPC practices; none met with the WHO minimum standards for environmental health. CONCLUSIONS: Adequate WASH facilities and IPC practices remain a critical component of maternal and child health even in non-facility birth. As the transition to facility births continues in many countries, the large number of non-facility births demands their inclusion in WASH-related strategies, if global goals of reducing deaths of newborns and women deaths will be achieved.

Can Clean Delivery Kits Prevent Infections? Lessons from Traditional Birth Attendants in Nigeria.

Background: In resource-poor settings, perinatal infections contribute significantly to maternal and neonatal deaths, and the use of clean delivery kits (CDKs) has been proposed as a tool to reduce the risk of infection-related deaths. This study aims to assess the acceptability and effectiveness of CDKs in preventing infections in deliveries attended by traditional birth attendants (TBAs) in Abeokuta, Nigeria. Methods: The study was a cluster-randomized trial with 67 birth centres/clusters, 453 births/mothers, and 457 babies randomized to intervention or control arms; intervention involved supplementation of delivery with JANMA CDKs. Interviews were conducted at the birth homes, and the primary outcomes were neonatal infection and puerperal fever. The association between infection and perinatal risk factors was tested using the Chi-square and Fisher's exact tests. Results: CDKs were well accepted by TBAs. The incidence of puerperal fever and neonatal infection was 1.1% and 11.2%, respectively. Concurrent infection was found in 1 (0.22%) of the mother-neonate pair. There was no significant association between any of the sociodemographic factors and infection for both mothers and neonates. PROM and prolonged labour were significantly associated with puerperal infection. All mothers with puerperal fever were from the control group. Compared to the control group, the relative risk of puerperal infection and neonatal infection in the intervention group was 0.08 (0.004 -1.35, p = 0.079) and 0.64 (0.37 to 1.1, p = 0.10), respectively. Conclusion: CDKs hold promising results in attenuating maternal infections in resource-poor settings. Larger studies with greater statistical power are required to establish statistically reliable information.

VEGFR-2 kinase domain inhibition as a scaffold for anti-angiogenesis: Validation of the anti-angiogenic effects of carotenoids from Spondias mombin in DMBA model of breast carcinoma in Wistar rats.

Vascular endothelial growth factor (VEGF) and its receptor-2 (VEGFR-2) mediated tumorigenesis, metastasis, and angiogenesis are the cause of the increased levels of mortality associated with breast cancer and other forms of cancer. Inhibition of VEGF and VEGFR-2 provides a great therapeutic option in the management of cancer. This study employed VEGFR-2 kinase domain inhibition as an anti-angiogenic scaffold and further validate the anti-angiogenic effects of the lead phytochemicals, carotenoids from Spondias mombin in 7, 12-Dimethylbenz[a]anthracene (DMBA) model of breast carcinoma in Wistar rats. Phytochemicals characterized from 6 reported anti-cancer plants were screened against the VEGFR-2 kinase domain. The lead phytochemicals, carotenoids from Spondias mombin were isolated and subjected to Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS) for characterization. The anti-angiogenic potentials of the carotenoid isolates were validated in the DMBA model of breast carcinoma in female Wistar rats through assessment of the expression of anti-angiogenic related mRNAs, histopathological analysis, and molecular docking. Treatment with carotenoid isolates (100 mg/kg and 200 mg/kg) significantly (p < 0.05) downregulated the expression of VEGF, VEGFR, Epidermal Growth Factor Receptor (EGFR), Hypoxia-Inducible Factor-1(HIF-1), and Matrix Metalloproteinase-2 (MMP-2) mRNAs in the mammary tumours, while the expression of Chromodomain Helicase DNA-Binding Protein-1 (CHD-1) mRNA was significantly (p < 0.05) upregulated. DMBA induced comedo and invasive ductal subtypes of breast carcinoma. The binding of astaxanthin, 7,7',8,8'-tetrahydro-ß,ß-carotene, and beta-carotene-15,15'-epoxide to the ATP binding site led to the DFG-out conformation with binding energies of -8.2 kcal/mol, -10.3 kcal/mol, and -10.5 kcal/mol respectively. Carotenoid isolates demonstrated anti-angiogenic and anti-proliferating potentials via VEGFR-2 kinase domain inhibition.

Carotenoid isolates of Spondias mombin demonstrate anticancer effects in DMBA-induced breast cancer in Wistar rats through X-linked inhibitor of apoptosis protein (XIAP) antagonism and anti-inflammation.

Breast cancer is the most prevalent cancer in women. X-linked inhibitor of apoptosis protein (XIAP) that is constantly overexpressed in cancer is a promising therapeutic target in cancer treatments. The mechanisms of the anticancer effects of carotenoid isolates of Spondias mombim in DMBA-induced breast cancer in Wistar rats through XIAP antagonism were investigated in the present study. Carotenoids isolated from the leaves of Spondias mombim were subjected to Liquid Chromatography/Mass Spectrometry (LC/MS) and Electrospray Ionization (ESI) for characterization. The characterized carotenoid isolates were docked against XIAP BIR2 domain and XIAP BIR3 domain. The anticancer effects of the carotenoid isolates of Spondias mombim in DMBA-induced breast cancer in Wistar rats were also investigated through the expression of XIAP, COX-2, TNF, BCl-2 mRNAs by qRT-PCR and biochemical parameters of catalase, lipid peroxidation, LDH, ALP, and ALT. These show the carotenoid isolates demonstrate anticancer effects by antagonism of XIAP, proapoptotic, and anti-inflammatory properties. PRACTICAL APPLICATIONS: The present study showed that carotenoids (astaxanthin, ß-carotene-15,15'-epoxide, and 7,7',8,8'-tetrahydro-ß, ß-carotene) isolated from the leaves of Spondias mombim are proapoptotic, it further gives credence to the chemopreventive abilities of carotenoids. This study validated XIAP as a druggable target in cancer treatment and hence more phytochemicals should be screened against it, for possible lead compounds of plant origin. Cancer cells often explore XIAP for antiapoptotic and resistance tendencies, hence, ß-carotene-15,15'-epoxide and 7,7',8,8'-tetrahydro-ß, ß-carotene (XIAP antagonists) are promising drug candidates that can withstand resistant and prone cancer cells to apoptotic cell death. There is a need to synthesize ß-carotene-15,15'-epoxide and 7,7',8,8'-tetrahydro-ß for further investigation in clinical studies.

Antimicrobial Resistance and Virulence of Methicillin-Resistant Staphylococcus aureus from Human, Chicken and Environmental Samples within Live Bird Markets in Three Nigerian Cities.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major threat to public health. This study investigated the occurrence of MRSA in humans, chickens, chicken meat and environmental samples within poultry farms and live bird markets in southwestern Nigeria. Methods: MRSA were isolated using selective culture and tested for antimicrobial susceptibility by broth microdilution. Selected isolates were characterized by whole genome sequencing (WGS). From WGS data, spa, dru, multilocus sequence typing (MLST) and SCCmec types, but also virulence and antimicrobial resistance genes, were identified. Results: Fifty-six MRSA isolates were detected in 734 samples. They showed resistance to ß-lactams (100%), tetracycline (60.7%), ciprofloxacin (33.9%), erythromycin (28.6%), gentamicin (32.1%), and trimethoprim/sulfamethoxazole (10.7%). All 30 isolates investigated by WGS carried mecA, dfrG, and tet(38) genes. Other resistance genes detected were blaZ (83.3%), fosB (73.3%), tet(K) (60.0%), aacA-aphD (36.6%), aphA3 (33.3%), msr(A) (30.0%), mph(C) (30.0%), dfrS1 (3.3%), and sat4 (3.3%). Seven spa types (t091, t314, t657, t1476, t2331, t4690 and t12236), four known (dt9aw, dt10ao, dt10cj, and dt11a) and two novel (dt10dr and dt11dw) dru types, as well as five sequence types (ST8, ST121, ST152, ST772 and ST789) were found among the MRSA isolates. All ST121 isolates carried an SCCmec type IV cassette and were not dru-typeable. ST152 and ST121 were found only in specific sample categories within defined locations, while ST8 and ST772 were distributed across most sample categories and locations. Three SCCmec types, IVa, V and Vc, were identified. All MRSA isolates possessed virulence genes including aur, clpP, coa, fnbA, esaA, hly, hla, ica, isdA, srtB, sspA, and vWbp, among others. The toxic shock syndrome toxin gene (tst) was not detected in any isolate, whereas the Pantone-Valentine leukocidin genes lukF-PV/lukS-PV were present in all ST121, all ST772, and all but one ST152 isolates. Conclusion: The results of this study (i) showed that chicken meat is contaminated by MRSA and (ii) suggested that live bird markets may serve as focal points for the dissemination of MRSA within the community.

Triple positivity of HBsAg, anti-HCV antibody, and HIV and their influence on CD4+ lymphocyte levels in the highly HIV infected population of Abeokuta, Nigeria.

BACKGROUND: Few studies exist on hospital-based seroprevalence of triple positivity of HIV/HBV/HCV in Nigeria. OBJECTIVES: The study aimed at determining the triple positivity of HIV, HBsAg and HCV among HIV-infected individuals in Abeokuta, Nigeria and defining the influence of these triple infections on CD4+ counts of HIV-infected individuals as antiretroviral therapy improves in Nigeria. METHODS: Enumeration of CD4+ levels in 183 HIV-infected persons was done with Partec Flow Cytometer. Seropositivity of HBsAg and anti-HCV antibody was detected with rapid kits. RESULTS: From the result obtained, significance variance (p<0.05) existed between HIV positive persons and persons who tested positive to HIV/HBV/HCV triple infection before and after the commencement of HAART. Of these infections, 31(16.9%) had HBV/HCV/HIV triple infection, while 152(83.1%) had HIV mono infection only, 56(30.6%) had HBV/HIV dual infection only and 43(23.5%) had HCV/HIV dual infection only. Significant variance (p<0.05) also existed between subjects with CD4 counts of <200 cells/µl, 200-499 cells/µl and >500 cells/µl. Highest seroprevalence of HIV (35.0%) was found in age groups 35-44 years and >65 years had the least (2.7%). Significant variance (p<0.05) also existed in the progression of CD4+ lymphocytes cells between subjects with persistent decrease (32.3%) in CD4+ lymphocytes cells and those with fluctuation in their CD4+ lymphocytes cells (12.9%) after the commencement of ART. CONCLUSION: The study further confirms that triple positivity of HIV/HBV/HCV infection is common in Abeokuta, Nigeria. Testing of these triple infections should be a big concern in the best choice and commencement of ART. Also, the study showed that consistent and prolonged use of HAART had a positive impact on the CD4 count of HIV-infected individuals.