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1.
Front Cell Infect Microbiol ; 14: 1366563, 2024.
Article in English | MEDLINE | ID: mdl-38716192

ABSTRACT

Background: Routine surveillance for antimalarial drug resistance is critical to sustaining the efficacy of artemisinin-based Combination Therapies (ACTs). Plasmodium falciparum kelch-13 (Pfkelch-13) and non-Pfkelch-13 artemisinin (ART) resistance-associated mutations are uncommon in Africa. We investigated polymorphisms in Plasmodium falciparum actin-binding protein (Pfcoronin) associated with in vivo reduced sensitivity to ART in Nigeria. Methods: Fifty-two P. falciparum malaria subjects who met the inclusion criteria were followed up in a 28-day therapeutic efficacy study of artemether-lumefantrine in Lagos, Nigeria. Parasite detection was done by microscopy and molecular diagnostic approaches involving PCR amplification of genes for Pf18S rRNA, varATS, telomere-associated repetitive elements-2 (TARE-2). Pfcoronin and Pfkelch-13 genes were sequenced bi-directionally while clonality of infections was determined using 12 neutral P. falciparum microsatellite loci and msp2 analyses. Antimalarial drugs (sulfadoxine-pyrimethamine, amodiaquine, chloroquine and some quinolones) resistance variants (DHFR_51, DHFR_59, DHFR_108, DHFR_164, MDR1_86, MDR1_184, DHPS_581 and DHPS_613) were genotyped by high-resolution melting (HRM) analysis. Results: A total of 7 (26.92%) cases were identified either as early treatment failure, late parasitological failure or late clinical failure. Of the four post-treatment infections identified as recrudescence by msp2 genotypes, only one was classified as recrudescence by multilocus microsatellites genotyping. Microsatellite analysis revealed no significant difference in the mean allelic diversity, He, (P = 0.19, Mann-Whitney test). Allele sizes and frequency per locus implicated one isolate. Genetic analysis of this isolate identified two new Pfcoronin SNVs (I68G and L173F) in addition to the P76S earlier reported. Linkage-Disequilibrium as a standardized association index, IAS, between multiple P. falciparum loci revealed significant LD (IAS = 0.2865, P=0.02, Monte-Carlo simulation) around the neutral microsatellite loci. The pfdhfr/pfdhps/pfmdr1 drug resistance-associated haplotypes combinations, (108T/N/51I/164L/59R/581G/86Y/184F), were observed in two samples. Conclusion: Pfcoronin mutations identified in this study, with potential to impact parasite clearance, may guide investigations on emerging ART tolerance in Nigeria, and West African endemic countries.


Subject(s)
Antimalarials , Artemisinins , Drug Resistance , Malaria, Falciparum , Plasmodium falciparum , Plasmodium falciparum/genetics , Plasmodium falciparum/drug effects , Antimalarials/pharmacology , Antimalarials/therapeutic use , Nigeria , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Drug Resistance/genetics , Artemisinins/pharmacology , Artemisinins/therapeutic use , Mutation , Protozoan Proteins/genetics , Artemether, Lumefantrine Drug Combination/therapeutic use , Male , Microfilament Proteins/genetics , Female , Drug Combinations , Microsatellite Repeats/genetics , Genotype , Sequence Analysis, DNA , Recurrence , Polymorphism, Genetic , Adult
2.
Mol Biol Rep ; 51(1): 665, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38777940

ABSTRACT

BACKGROUND: Staphylococcus aureus (S. aureus) associated with COVID-19 has not been well documented. This cross-sectional study evaluated the association between nasal S. aureus carriage and COVID-19. METHODS AND RESULTS: Nasopharyngeal samples were collected from 391 participants presenting for COVID-19 test in Lagos, Nigeria, and S. aureus was isolated from the samples. Antimicrobial susceptibility test was done by disc diffusion method. All S. aureus isolates were screened for the presence of mecA, panton-valentine leucocidin (PVL) and toxic shock syndrome toxin (TSST) virulence genes by polymerase chain reaction. Staphylococcal protein A (spa) typing was conducted for all the isolates. Participants with COVID-19 had double the prevalence of S. aureus (42.86%) compared to those who tested negative (20.54%). A significant association was seen between S. aureus nasal carriage and COVID-19 (p = 0.004). Antimicrobial sensitivity results showed resistance to oxacillin (100%), cefoxitin (53%), and vancomycin (98.7%). However, only 41% of the isolates harbored the mecA gene, with SCCmecV being the most common SCCmec type. There was no association between the carriage of virulence genes and COVID-19. A total of 23 Spa types were detected, with t13249 and t095 being the two most common spa types. CONCLUSION: This study examined the association between nasal S. aureus carriage and SARS-COV-2 infection. Further research is required to fully explore the implications of S. aureus co-infection with COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , Staphylococcal Infections , Staphylococcus aureus , Humans , COVID-19/microbiology , COVID-19/epidemiology , COVID-19/virology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Cross-Sectional Studies , Male , Female , Staphylococcus aureus/genetics , Staphylococcus aureus/drug effects , Staphylococcus aureus/pathogenicity , Staphylococcus aureus/isolation & purification , Adult , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Middle Aged , Bacterial Toxins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Methicillin-Resistant Staphylococcus aureus/drug effects , Comorbidity , Bacterial Proteins/genetics , Virulence/genetics , Nigeria/epidemiology , Drug Resistance, Multiple, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Carrier State/epidemiology , Carrier State/microbiology , Microbial Sensitivity Tests , Penicillin-Binding Proteins/genetics , Leukocidins/genetics , Exotoxins/genetics , Virulence Factors/genetics , Young Adult
3.
IJID Reg ; 10: 174-178, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38322246

ABSTRACT

Objectives: The emergence and spread of SARS-CoV-2 have stimulated ongoing research into the virus transmission dynamics, circulating variants, and potential mutations. This study was conducted to understand the genomic dynamics of the epidemic in Nigeria. Design: Whole genome sequencing was conducted on SARS-CoV-2 samples collected during the first and second outbreaks using the Oxford Nanopore MinION sequencing platform. Phylogenetic analysis was conducted, and genomes were grouped into different pangolin lineages. Results: The study revealed four circulating SARS-CoV-2 variants. The Alpha (B.1.1.7) variant was the most prevalent (32.7%), followed by Beta (B.1 B.1.1, L.3, and B.1.1.318) (30.8%), Eta (B.1.525) (28.9%), and Delta (B.1.617, AY.1, AY.109, and AY.36) (7.7%). Phylogenetic analysis revealed three clusters with four Nextstrain clades (20I, 20B, 21D, and 21J). The Alpha lineages (B.1.1.7) clustered with references from Italy. The Beta lineages (Clade 20B) (B.11, B.11318, and L3) and sub-lineage B.11 were distinct. Sub-lineage B.11318 is clustered with references from the USA, whereas sub-lineage L3 is clustered with references from Russia, the Philippines, Australia, and Japan. The 21D and 21J, belonging to two Pango lineages, Eta (B.1525) and Delta (B.1.617 and AY.109), showed high genetic similarity. Conclusion: The phylogenetic relatedness of the lineages suggests multiple virus introduction, which could be a source of more virulent, locally adapted variants.

4.
Am J Cancer Res ; 13(7): 2773-2789, 2023.
Article in English | MEDLINE | ID: mdl-37559981

ABSTRACT

Cancer is one of the most common and widely diagnosed diseases worldwide. With an increase in prevalence and incidence, many studies in cancer biology have been looking at the role pro-cancer proteins play. One of these proteins is the Really Interesting New Gene (RING), which has been studied extensively due to its structure and functions such as apoptosis, neddylation, and its role in ubiquitination. The RING domain is a cysteine-rich domain known to bind Cysteine and Histidine residues. It also binds two zinc ions that help stabilize the protein in various patterns, often with a 'cross-brace' topology. Different RING finger proteins have been studied and found to have suitable targets for developing anti-cancer therapeutics. These identified candidate proteins include Parkin, COP1, MDM2, BARD1, BRCA-1, PIRH2, c-CBL, SIAH1, RBX1 and RNF8. Inhibiting these candidate proteins provides opportunities for shutting down pathways associated with tumour development and metastasis.

5.
JAC Antimicrob Resist ; 5(2): dlad038, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37051191

ABSTRACT

Background: Carbapenem-resistant Pseudomonas aeruginosa strains are on the rise worldwide. This study characterized clinical isolates of P. aeruginosa from three Nigerian hospitals for carbapenem resistance. Methods: Strains isolated from wounds (n = 88), urine/catheter tips (n = 25), sputum/tracheotomy aspirates (n = 5), ear swabs (n = 4) and vaginal swabs (n = 1) were identified by MALDI-TOF and antibiotic susceptibility testing was performed using the VITEK 2 system. The genomic DNA of each isolate was subject to sequencing using Illumina and Oxford nanopore technology. Bioinformatics analyses were performed to detect antimicrobial resistance genes, clonal affiliations and phylogenetic relations of 123 non-duplicate P. aeruginosa isolates, whereas assembly of the nanopore reads using the plasmIDent pipeline enabled the identification of plasmids. Results: Forty-three percent of the isolates were resistant to all antibiotic categories tested. More than 40% of the isolates were resistant to the carbapenems imipenem and/or meropenem (39% and 44%, respectively). Among the meropenem-resistant isolates, 48 (89%) carried at least one carbapenemase gene. The predominant one was bla NDM-1 (n = 34), which conferred resistance to all five antibiotic categories and highly increased the MICs of both meropenem and imipenem. The other recurrent carbapenemase genes were bla VIM-2 (n = 4), and bla VIM-5-like (n = 11), which co-existed with bla NDM-1 in two isolates. Conclusions: The study revealed a high rate of carbapenem resistance and conjugative, broad host range plasmids carrying carbapenemase-encoding genes, especially the NDM-1 type, among isolates of P. aeruginosa. This may forebode the emergency of ubiquitous carbapenem resistance urging the implementation of infection control and antimicrobial stewardship strategies in Nigerian hospitals.

6.
Am J Case Rep ; 24: e938761, 2023 Mar 31.
Article in English | MEDLINE | ID: mdl-36998203

ABSTRACT

BACKGROUND Bacterial Infections, especially, of the respiratory system, have been reported as one of the medical concerns in patients with the Coronavirus Disease-2019 (COVID-19), particularly those with multiple co-morbidities. We present a case of a diabetic patient with co-infection of multi-drug-resistant Kocuria rosea and methicillin-resistant Staphylococcus aureus (MRSA) who contracted COVID-19. CASE REPORT A 72-year-old man with diabetes presented with symptoms including cough, chest pain, urinary incontinence, respiratory distress, sore throat, fever, diarrhea, loss of taste, and anosmia and was confirmed to have COVID-19. At admission, he was also found to have sepsis. MRSA was isolated in conjunction with another organism, resembling coagulase-negative Staphylococcus, which was misidentified using commercial biochemical testing systems. The strain was finally confirmed to be Kocuria rosea by 16S rRNA gene sequencing. Both strains were highly resistant to multiple classes of antibiotics, but the Kocuria rosea was resistant to all the cephalosporins, fluoroquinolones, and macrolides tested. The use of ceftriaxone and ciprofloxacin did not improve his condition, which ultimately led to his death. CONCLUSIONS This case report shows that the presence of multi-drug-resistant bacteria infections can be fatal in patients with COVID-19, especially in patients with other co-morbidities like diabetes. This case report also shows that biochemical testing may be inadequate in identifying emerging bacterial infections and there is a need to include proper bacterial screening and treatment in the management of COVID-19, especially in patients with other co-morbidities and with indwelling devices.


Subject(s)
COVID-19 , Coinfection , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Male , Humans , Aged , RNA, Ribosomal, 16S/genetics , Staphylococcal Infections/diagnosis , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Anti-Bacterial Agents/therapeutic use
7.
J Immunoassay Immunochem ; 44(2): 117-132, 2023 Mar 04.
Article in English | MEDLINE | ID: mdl-36576163

ABSTRACT

Data on spatiotemporal distribution of rotavirus diarrhea are limited in many endemic settings. This study determined the prevalence and seasonal distribution of rotavirus among Nigerian children with diarrhea. Here, a total of 406 fecal samples were collected from patients attending six health facilities in Lagos between January - December 2019. Socio-demographic data of each enrolled child were collected. Rotavirus VP6 antigen was detected by enzyme-linked immunoassay (ELISA) and confirmation by VP7 gene detection by reverse transcription polymerase-chain reaction. The overall rotavirus diarrhea prevalence was 16.3% by ELISA with children above 2 years having 29.2% of this prevalence and higher occurrence in females (59.1%) than males (40.9%) (P < .05). Rotavirus diarrhea diagnosis using RT-PCR showed 100% concordance with ELISA. Cases of rotavirus diarrhea were detected from March to July and from September to November with the highest number of cases detected in May and June (22.7% each), followed by July (21.2%). The prevalence of rotavirus diarrhea remains high in Lagos with an emerging higher disease activity in children above 2. A different rotavirus transmission dynamics compared to previous studies from Nigeria and other African countries was found. VP6 ELISA may reliably be used for continuous rotavirus surveillance in Nigeria.


Subject(s)
Rotavirus Infections , Rotavirus , Male , Female , Humans , Child , Infant , Child, Preschool , Rotavirus/genetics , Rotavirus Infections/epidemiology , Nigeria/epidemiology , Prevalence , Diarrhea/epidemiology , Feces , Antigens, Viral/genetics , Genotype
8.
Rev Invest Clin ; 74(3): 165-171, 2022.
Article in English | MEDLINE | ID: mdl-35797697

ABSTRACT

BACKGROUND: There is scarce information about the occurrence of extended-spectrum ß-lactamases (ESBLs) in Salmonella enterica serovar Typhi (S. Typhi) from patients with typhoid fever. OBJECTIVE: To study the antimicrobial resistance and ESBL encoding genes among S. Typhi isolates in aforesaid patients from Lagos, Nigeria. METHODS: S. Typhi isolates were collected from blood samples of typhoid fever patients from 4 academic medical centers in Lagos, Nigeria. The identification of isolates and their antibiotic susceptibility testing were performed by standard bacteriological techniques and disc diffusion method, respectively. The production of ESBLs was investigated using combination disk test (CDT) and polymerase chain reaction (PCR). RESULTS: A total of 27 S. Typhi isolates was collected. All isolates were susceptible to imipenem and nitrofurantoin. Fifteen (55.6%) isolates were multidrug-resistant (MDR). The CDT test showed 11 (40.7%) ESBL producer isolates. However, the PCR revealed a higher occurrence rate for ESBL producers (66.7%, n = 18/27). The ESBL genes were as follows: blaCTX-M (37.0%, n = 10/27), blaSHV (18.5%, n = 5/27), and blaTEM (44.4%, n = 12/27). All ESBL positive S. Typhi isolates were MDR. CONCLUSIONS: This study showed the emergence of ESBL-harboring S. Typhi in patients with typhoid fever from Nigeria.


Subject(s)
Salmonella typhi , Typhoid Fever , Academic Medical Centers , Anti-Bacterial Agents/pharmacology , Humans , Microbial Sensitivity Tests , Nigeria/epidemiology , Salmonella typhi/genetics , Typhoid Fever/drug therapy , Typhoid Fever/epidemiology , beta-Lactamases/genetics
9.
Data Brief ; 42: 108269, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35647232

ABSTRACT

In an integrated poultry-fish (IPF) farming system, fish and bird are reared simultaneously. It is a common practice in Sub-Saharan Africa countries like Nigeria, Cameroon, Madagascar, and Benin, offering economic benefits to farmers and minimizing farm running costs. It seems like another way for farmers to manage poultry waste as it is a common practice in IPF farm settings to feed reared fishes with wastes emanating from the poultry. This work provides dataset on the bacterial taxonomic profile and abundance in IPF farm pond water samples using the 16S rRNA sequencing approach. Using ZymoBIOMICS®-96 MagBead DNA Kit, total DNA was extracted from pond water samples collected from IPF farm located at Ila-Orangun, Osun State, Southwest Nigeria (Long: 8° 1' N; Lat: 4° 54' E) during two sampling visits. The V3-V4 region of the rRNA gene was amplified and sequenced on the Miseq Illumina sequencing platform. Raw reads obtained after demultiplexing were analyzed using DADA2 pipeline to obtain distinctive or unique amplicon sequence variants which were grouped into Operational Taxonomic Units (OTUs) based on similarities. Taxonomy assignment was performed using UCLUST and Bayesian classifier from QIIME v.1.9.1 with the Zymo Research Database as reference. The phyla Proteobacteria (26.7%), Actinobacteria (26.0%), Firmicutes (13.1%), and Cyanobacteria (10.1%) dominated the 35 phyla obtained from the OTUs. Interestingly, the abundance of bacterial pathogens commonly associated with human infections was low. The sequence and sample data have been deposited in NCBI database under Sequence Read Archive (SRA) with Bioproject identification number PRJNA760919 (Accession number: SRX12020336 - SRX12020346). The dataset obtained can bridge the gap of limited information on the impact of IPF farming on pond bacterial diversity, a critical factor for considerations as regards food safety, fish, and public health.

10.
Rev. invest. clín ; 74(3): 165-171, May.-Jun. 2022. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1409575

ABSTRACT

ABSTRACT Background: There is scarce information about the occurrence of extended-spectrum β-lactamases (ESBLs) in Salmonella enterica serovar Typhi (S. Typhi) from patients with typhoid fever. Objective: To study the antimicrobial resistance and ESBL encoding genes among S. Typhi isolates in aforesaid patients from Lagos, Nigeria. Methods: S. Typhi isolates were collected from blood samples of typhoid fever patients from 4 academic medical centers in Lagos, Nigeria. The identification of isolates and their antibiotic susceptibility testing were performed by standard bacteriological techniques and disc diffusion method, respectively. The production of ESBLs was investigated using combination disk test (CDT) and polymerase chain reaction (PCR). Results: A total of 27 S. Typhi isolates was collected. All isolates were susceptible to imipenem and nitrofurantoin. Fifteen (55.6%) isolates were multidrug-resistant (MDR). The CDT test showed 11 (40.7%) ESBL producer isolates. However, the PCR revealed a higher occurrence rate for ESBL producers (66.7%, n = 18/27). The ESBL genes were as follows: blaCTX-M (37.0%, n = 10/27), blaSHV (18.5%, n = 5/27), and blaTEM (44.4%, n = 12/27). All ESBL positive S. Typhi isolates were MDR. Conclusions: This study showed the emergence of ESBL-harboring S. Typhi in patients with typhoid fever from Nigeria.

12.
Ecancermedicalscience ; 15: 1266, 2021.
Article in English | MEDLINE | ID: mdl-34567251

ABSTRACT

Epidemiological studies have showed that low levels of antioxidants induce the generation of free radicals leading to DNA damage and further mutations seen in cancer. This study evaluated the effects of oxidative markers on the occurrence and severity of cervical cancer at the Lagos University Teaching Hospital. This was an analytical cross-sectional study carried out among women with histological diagnosis of invasive cervical cancer and their healthy cancer-free comparison group. Venous blood samples were collected from each participant for measurements of antioxidants (erythrocyte glutathione and vitamin C) and malondialdehyde (a marker of lipid peroxidation). Descriptive statistics were carried out for relevant demographic and clinical data. Associations between continuous variables were tested using the independent sample t-test or the analysis of variance for normally distributed data or the Mann-Whitney U test for skewed data, whereas categorical variables were compared using the χ2 test. p < 0.05 was considered statistically significant. The mean level of malondialdehyde (MDA) was statistically higher in women with cervical cancer than in their cancer-free counterparts (p = 0.032). However, the mean glutathione (32.6 ± 6.2 versus 14.2 ± 6.1 mg/dL; p = 0.019) and vitamin C (12.4 ± 2.3 versus 14.6 ± 2.4 µmol/L; p = 0.001) levels were significantly lower in the case group compared to the cancer-free group. There are statistically increasing mean levels of MDA (p = 0.017) and decreasing mean levels of vitamin C (p = 0.004) with increasing stages of the disease. This study showed that women with cervical cancer have low levels of antioxidants and an increased level of the oxidative marker. The levels of these markers become more pronounced as the disease progresses. This will, therefore, form the basis for the conduct of future randomised controlled trials of antioxidant supplementations among cervical cancer patients in sub-Saharan Africa.

13.
Microbiol Resour Announc ; 10(19)2021 May 13.
Article in English | MEDLINE | ID: mdl-33986090

ABSTRACT

Escherichia coli laboratory strains remain instrumental for the development of tools and techniques in molecular microbiology. The transcriptional regulator SlyA, associated with host-derived oxidative stress, antibiotic resistance, and virulence, is prominent in Enterobacteriaceae Here, we announce a transcriptome data set detailing the global gene expression in E. coli BW25113 and its slyA mutant.

14.
J Clin Lab Anal ; 35(6): e23802, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33938598

ABSTRACT

BACKGROUND: Stroke is a devastating complication of sickle cell anemia (SCA) and can be predicted through abnormally high cerebral blood flow velocity using transcranial Doppler Ultrasonography (TCD). The evidence on the role of alpha-thalassemia and glucose-6-phosphate dehydrogenase (G6PD) deficiency in the development of stroke in children with SCA is conflicting. Thus, this study investigated the association of alpha-thalassemia and G6PD(A- ) variant with abnormal TCD velocities among Nigerian children with SCA. METHODS: One hundred and forty-one children with SCA were recruited: 72 children presented with normal TCD (defined as the time-averaged mean of the maximum velocity: < 170 cm/s) and 69 children with abnormal TCD (TAMMV ≥ 200 cm/s). Alpha-thalassemia (the α-3.7 globin gene deletion) was determined by multiplex gap-PCR, while G6PD polymorphisms (202G > A and 376A > G) were genotyped using restriction fragment length polymorphism-polymerase chain reaction. RESULTS: The frequency of α-thalassemia trait in the children with normal TCD was higher than those with abnormal TCD: 38/72 (52.8%) [α-/ α α: 41.7%, α -/ α -: 11.1%] versus 21/69 (30.4%) [α-/ α α: 27.5%, α -/ α -: 2.9%], and the odds of abnormal TCD were reduced in the presence of the α-thalassemia trait [Odds Ratio: 0.39, 95% confidence interval: 0.20-0.78, p = 0.007]. However, the frequencies of G6PDA- variant in children with abnormal and normal TCD were similar (11.6% vs. 15.3%, p = 0.522). CONCLUSION: Our study reveals the protective role of α-thalassemia against the risk of abnormal TCD in Nigerian children with SCA.


Subject(s)
Anemia, Sickle Cell/physiopathology , Glucosephosphate Dehydrogenase Deficiency/complications , Stroke/pathology , alpha-Thalassemia/complications , Adolescent , Blood Flow Velocity , Case-Control Studies , Cerebrovascular Circulation , Child , Child, Preschool , Female , Follow-Up Studies , Glucosephosphate Dehydrogenase Deficiency/diagnostic imaging , Glucosephosphate Dehydrogenase Deficiency/pathology , Humans , Male , Nigeria/epidemiology , Prognosis , Stroke/diagnostic imaging , Stroke/epidemiology , Stroke/etiology , Ultrasonography, Doppler, Transcranial , alpha-Thalassemia/diagnostic imaging , alpha-Thalassemia/pathology
15.
JMIR Res Protoc ; 10(3): e21242, 2021 Mar 04.
Article in English | MEDLINE | ID: mdl-33621190

ABSTRACT

BACKGROUND: The COVID-19 pandemic, caused by SARS-CoV-2, continues to impact health systems throughout the world with serious medical challenges being imposed on many African countries like Nigeria. Although emerging studies have identified lymphopenia as a driver of cytokine storm, disease progression, and poor outcomes in infected patients, its immunopathogenesis, as well as environmental and genetic determinants, remain unclear. Understanding the interplay of these determinants in the context of lymphopenia and COVID-19 complications in patients in Africa may help with risk stratification and appropriate deployment of targeted treatment regimens with repurposed drugs to improve prognosis. OBJECTIVE: This study is designed to investigate the role of vitamin D status, vasculopathy, apoptotic pathways, and vitamin D receptor (VDR) gene polymorphisms in the immunopathogenesis of lymphopenia among African people infected with SARS-CoV-2. METHODS: This cross-sectional study will enroll 230 participants, categorized as "SARS-CoV-2 negative" (n=69), "COVID-19 mild" (n=32), "hospitalized" (n=92), and "recovered" (n=37), from two health facilities in Lagos, Nigeria. Sociodemographic data, travel history, and information on comorbidities will be obtained from case files and through a pretested, interview-based structured questionnaire. Venous blood samples (5 mL) collected between 8 AM and 10 AM and aliquoted into EDTA (ethylenediaminetetraacetic acid) and plain tubes will be used for complete blood count and CD4 T cell assays to determine lymphopenia (lymphocyte count <1000 cells/µL) and CD4 T lymphocyte levels, as well as to measure the concentrations of vitamin D, caspase 3, soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble Fas ligand (sFasL) using an autoanalyzer, flow cytometry, and ELISA (enzyme-linked immunosorbent assay) techniques. Genomic DNA will be extracted from the buffy coat and used as a template for the amplification of apoptosis-related genes (Bax, Bcl-2, BCL2L12) by polymerase chain reaction (PCR) and genotyping of VDR (Apa1, Fok1, and Bsm1) gene polymorphisms by the PCR restriction fragment length polymorphism method and capillary sequencing. Total RNA will also be extracted, reverse transcribed, and subsequently quantitated by reverse transcription PCR (RT-PCR) to monitor the expression of apoptosis genes in the four participant categories. Data analyses, which include a test of association between VDR gene polymorphisms and study outcomes (lymphopenia and hypovitaminosis D prevalence, mild/moderate and severe infections) will be performed using the R statistical software. Hardy-Weinberg equilibrium and linkage disequilibrium analyses for the alleles, genotypes, and haplotypes of the genotyped VDR gene will also be carried out. RESULTS: A total of 45 participants comprising 37 SARS-CoV-2-negative and 8 COVID-19-recovered individuals have been enrolled so far. Their complete blood counts and CD4 T lymphocyte counts have been determined, and their serum samples and genomic DNA and RNA samples have been extracted and stored at -20 °C until further analyses. Other expected outcomes include the prevalence and distribution of lymphopenia and hypovitaminosis D in the control (SARS-CoV-2 negative), confirmed, hospitalized, and recovered SARS-CoV-2-positive participants; association of lymphopenia with CD4 T lymphocyte level, serum vitamin D, sVCAM-1, sFasL, and caspase 3 levels in hospitalized patients with COVID-19; expression levels of apoptosis-related genes among hospitalized participants with COVID-19, and those with lymphopenia compared to those without lymphopenia; and frequency distribution of the alleles, genotypes, and haplotypes of VDR gene polymorphisms in COVID-19-infected participants. CONCLUSIONS: This study will aid in the genotypic and phenotypic stratification of COVID-19-infected patients in Nigeria with and without lymphopenia to enable biomarker discovery and pave the way for the appropriate and timely deployment of patient-centered treatments to improve prognosis. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/21242.

16.
Antibiotics (Basel) ; 10(2)2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33535654

ABSTRACT

This study investigated the prevalence of Klebsiella (K.) pneumoniae isolates among clinical samples of patients in four medical centers in Lagos, Nigeria and the burden of extended-spectrum beta-lactamases (ESBL) and carbapenem-resistant K. pneumoniae (CRKP) strains. Different samples (stool, blood, urine, wound swabs and nasal swabs) from 127 patients with suspected Gram-negative infections based on on-site performed Gram-stain from four public hospitals between March and September 2015 were analyzed. K. pneumoniae was identified in 43 (34%) patients. Resistance rates of these 43 strains according to the CLSI breakpoints were as followed: cotrimoxazole (90.7%), cefuroxime (74.4%), ofloxacin (55.8%), ceftazidime (46.5%), and cefixime (35%). Three isolates (7%) were resistant to imipenem. All isolates were susceptible to amoxicillin/clavulanic acid and nitrofurantoin. The prevalence of ESBL-producing, MDR and CRKP strains was 69.8%, 62.8%, and 7.0%, respectively. Of the ESBL-producing isolates, two K. pneumoniae isolates obtained from urine harbored both blaSHV and blaCTX-M-1, and a third isolate from urine harbored only the blaCTX-M-1. This study revealed the emergence of CRKP isolates and blaCTX-M-1 and blaSHV co-harboring K. pneumoniae strains in Lagos hospitals. The emergence of CRKP strains is an early warning signal for carbapenem antibiotics' prudent use with concern for their efficacies.

17.
J Natl Med Assoc ; 113(3): 301-306, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33358220

ABSTRACT

INTRODUCTION: COVID-19 is an emerging, rapidly evolving global situation, infecting over 25 million people and causing more than 850,000 deaths. Several signs and symptoms have been described to be characteristic of the disease. However, there is a dearth of report on the description of the clinical characteristics of the disease in patients from Nigeria. This study was designed to provide a description of the clinical and demographic characteristics of COVID-19 patients in Nigeria. METHODS: This study is a case series that includes patients that are evaluated between May and August 2020, and diagnosed with COVID-19. Patient health records were reviewed and evaluated to describe the clinical characteristics on presentation. RESULTS: A total of 154 COVID-19 patients were included in this study, with a mean age (S.D.) of 46.16 (13.701). Most of the patients survived (mortality rate of 2.6%), and were symptomatic (89.6%). There were more males (74.7%) than females, and the most common symptoms were fever, breathing difficulty, dry cough and malaise. Co-morbidities were also present in almost half of the study participants (49.4%). CONCLUSION: This study presents the most extensive description, to date, on the clinical and demographic characteristics of COVID-19 patients in Nigeria. Males are more likely than females to be infected with COVID-19 and the most occurring symptoms are fever, breathing difficulty, malaise, dry cough and chest pain. Old age and the presence of co-morbidities may also be associated with developing the severe disease.


Subject(s)
COVID-19/epidemiology , Pneumonia, Viral/epidemiology , Comorbidity , Demography , Female , Humans , Male , Middle Aged , Nigeria/epidemiology , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2 , Sex Factors
18.
Afr J Lab Med ; 9(1): 1255, 2020.
Article in English | MEDLINE | ID: mdl-33102170

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has impacted heavily on global health. Although real-time polymerase chain reaction (RT-PCR) is the current diagnostic method, challenges for low- and middle-income countries (LMICs) necessitate cheaper, higher-throughput, reliable rapid diagnostic tests (RDTs). OBJECTIVE: We reviewed the documented performance characteristics of available COVID-19 RDTs to understand their public health utility in the ongoing pandemic, especially in resource-scarce LMIC settings. METHODS: Using a scoping review methodology framework, common literature databases and documentary reports were searched up to 22 April 2020, irrespective of geographical location. The search terms included 'SARS-CoV-2 AND serological testing' and 'COVID-19 AND serological testing'. RESULTS: A total of 18 RDTs produced in eight countries, namely China (6; 33.33%), the United States (4; 22.22%), Germany (2; 11.11%), Singapore (2; 11.11%), Canada, Kenya, Korea and Belgium (1 each; 5.56%), were evaluated. Reported sensitivity ranged from 18.4% to 100% (average = 84.7%), whereas specificity ranged from 90.6% to 100% (average = 95.6%). The testing time ranged from 2 min to 30 min. Of the 12 validated RDTs, the IgM/IgG duo kit with non-colloidal gold labelling system was reported to elicit the highest sensitivity (98% - 100%) and specificity (98% - 99% for IgG and 96% - 99% for IgM). CONCLUSION: We found reports of high sensitivity and specificity among the developed RDTs that could complement RT-PCR for the detection of SARS-CoV-2 antibodies, especially for screening in LMICs. However, it is necessary to validate these kits locally.

19.
JMIR Res Protoc ; 9(1): e14820, 2020 Jan 17.
Article in English | MEDLINE | ID: mdl-31951214

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) is a burgeoning epidemic in sub-Saharan Africa. Abnormal blood pressure variations are prevalent in CKD and potentiate the risk of cardiovascular morbidity and mortality. Certain genetic variants (angiotensin II receptor type 1 1166 A>C and angiotensin-converting enzyme insertion and deletion polymorphisms) and biomarkers such as interleukin-6, tumor necrosis factor, soluble (s) E-selectin, homocysteine, and highly sensitive C-reactive protein have been shown to affect blood pressure variability among non-African CKD, hypertensive. and nonhypertensive CKD population. However, the contributions of the pattern, genetic, and environmental determinants of ambulatory blood pressure in African CKD have not been characterized. Understanding these interactions may help to develop interventions to prevent major cardiovascular events among people with CKD. OBJECTIVE: The overarching objective of this study is to identify, document, and develop approaches to address related phenomic, genetic, and environmental determinants of ambulatory blood pressure patterns in African CKD and non-CKD hypertensive patients compared with normotensive controls. METHODS: This is a longitudinal short-term follow-up study of 200 adult subjects with CKD and 200 each of age-matched hypertensives without CKD and apparently healthy controls. Demographic information, detailed clinical profile, electrocardiography, echocardiography, and 24-hr ambulatory blood pressure measurements will be obtained. Blood samples will be collected to determine albumin-creatinine ratio, fasting plasma glucose, lipid profile, electrolytes, urea and creatinine, C-reactive protein, serum homocysteine, fibroblast growth factor-23, and complete blood count, while 2 mL blood aliquot will be collected in EDTA (ethylenediaminetetraacetic acid) tubes and mixed using an electronic rolling system to prevent blood clots and subsequently used for DNA extraction and genetic analysis. RESULTS: A total of 239 participants have been recruited so far, and it is expected that the recruitment phase will be complete in June 2020. The follow-up phase will continue with data analysis and publications of results. CONCLUSIONS: This study will help stratify Nigerian CKD patients phenotypically and genotypically in terms of their blood pressure variations with implications for targeted interventions and timing of medications to improve prognosis. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/14820.

20.
Malar J ; 19(1): 6, 2020 Jan 06.
Article in English | MEDLINE | ID: mdl-31906953

ABSTRACT

BACKGROUND: Vaccines are the most reliable alternative to elicit sterile immunity against malaria but their development has been hindered by polymorphisms and strain-specificity in previously studied antigens. New vaccine candidates are therefore urgently needed. Highly conserved Plasmodium falciparum reticulocyte-binding protein homologue-5 (PfRH5) has been identified as a potential candidate for anti-disease vaccine development. PfRH5 is essential for erythrocyte invasion by merozoites and crucial for parasite survival. However, there is paucity of data on the extent of genetic variations on PfRH5 in field isolates of Plasmodium falciparum. This study described genetic polymorphisms at the high affinity binding polypeptides (HABPs) 36718, 36727, 36728 of PfRH5 in Nigerian isolates of P. falciparum. This study tested the hypothesis that only specific conserved B and T cell epitopes on PfRH5 HABPs are crucial for vaccine development. METHODS: One hundred and ninety-five microscopically confirmed P. falciparum samples collected in a prospective cross-sectional study of three different populations in Lagos, Nigeria. Genetic diversity and haplotype construct of Pfrh5 gene were determined using bi-directional sequencing approach. Tajima's D and the ratio of nonsynonymous vs synonymous mutations were utilized to estimate the extent of balancing and directional selection in the pfrh5 gene. RESULTS: Sequence analysis revealed three haplotypes of PfRH5 with negative Tajima's D and dN/dS value of - 1.717 and 0.011 ± 0.020, respectively. A single nucleotide polymorphism, SNP (G → A) at position 608 was observed, which resulted in a change of the amino acid cysteine at position 203 to tyrosine. Haplotype and nucleotide diversities were 0.318 ± 0.016 and 0.0046 ± 0.0001 while inter-population genetic differentiation ranged from 0.007 to 0.037. Five polypeptide variants were identified, the most frequent being KTKYH with a frequency of 51.3%. One B-cell epitope, 151 major histocompatibility complex (MHC) class II T-cell epitopes, four intrinsically unstructured regions (IURs) and six MHC class I T-cell epitopes were observed in the study. Phylogenetic analysis of the sequences showed clustering and evidence of evolutionary relationship with 3D7, PAS-2 and FCB-2 RH5 sequences. CONCLUSIONS: This study has revealed low level of genetic polymorphisms in PfRH5 antigen with B- and T-cell epitopes in intrinsically unstructured regions along the PfRH5 gene in Lagos, Nigeria. A broader investigation is however required in other parts of the country to support the possible inclusion of PfRH5 in a cross-protective multi-component vaccine.


Subject(s)
Carrier Proteins/genetics , Carrier Proteins/immunology , Malaria Vaccines/genetics , Malaria Vaccines/immunology , Polymorphism, Single Nucleotide , Antibodies, Protozoan/immunology , Antigens, Protozoan/genetics , Antigens, Protozoan/immunology , Cross-Sectional Studies , Epitopes, B-Lymphocyte , Epitopes, T-Lymphocyte , Erythrocytes/parasitology , Gene Flow , Haplotypes , Histocompatibility , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Malaria, Falciparum/prevention & control , Merozoites/immunology , Nigeria , Phylogeny , Plasmodium falciparum/genetics , Plasmodium falciparum/isolation & purification , Prospective Studies , Sequence Analysis
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