Pulmonary tuberculosis and resistance pattern to first line anti-tuberculosis drugs in a city of Western Nigeria

This study determines the distribution of pulmonary tuberculosis (PTB) among suspected patients and the resistance pattern of Mycobacterium tuberculosis to first line anti-tuberculosis drugs. 609 suspected PTB subjects (based on chest x-ray), attending tuberculosis clinic at Sacred Heart Hospital, Abeokuta, were involved in this study. Their blood  samples were screened for HIV antibody using WHO strategy II, while sputum samples were screened for the presence of acid fast bacilli (AFB) using standard method. All AFB positive samples were cultured and susceptibility tests done using 1% proportion methods. Results showed that of the 609 subjects, 19.7% had PTB. The observed infection, though not statistically significant, was higher among males (21.6%) than in females. However, significant differences were observed for PTB infections amongst various age groups. Susceptibility test revealed that resistance to streptomycin was highest (33.0%) compared to other drugs, while detected multidrugresistant tuberculosis (MDR-TB) was 17.5%; being higher among males (19.7%) and in subjects with PTB only (19.3). In addition,  mono-resistant and poly-resistance was found in 16.5% and 9.7% of the isolates respectively. These findings suggest that the control and prevention of PTB, especially MDR-TB, should include measures aimed at identifying the source of infection and proper treatment of infected individuals.Key Words: Gender, Pulmonary tuberculosis, Mycobacterium tuberculosis, Susceptibility test

CD4 and CD8 counts of Bacillus Calmette Guerin (BCG) vaccinated neonates in parts of Edo and Delta States, Nigeria

This study examines the cellular immune factors responsible for combating infections by assessing CD4 and CD8 counts of neonates (pre and post BCG vaccination). A total of 373 blood samples were collected from neonates that visited the immunization clinics at Irrua Specialist Teaching Hospital (ISTH), Irrua and Federal Medical Centre (FMC), Asaba, Nigeria. CD4 and CD8 easy count kit (Partec, Germany) was used for the determination of CD4 and CD8  count respectively, while the samples were analysed using SL-blue Cyflow. At ISTH Irrua, 191 samples were analyzed (130:60; pre and post vaccination), while at Asaba, 182 samples were analysed (120:62; pre and post vaccination). The results showed that CD4 count was significantly higher for Pre vaccination than Post vaccination at both locations. At FMC Asaba, the CD4 count for females was significantly higher than in males (pre-BCG vaccination), while CD4 count was not significantly affected by gender at Irrua, ISTH. CD8 increases in both locations but was not significantly affected by gender. The findings of this study therefore suggests that there is a cell mediated immune response to BCG vaccine by both the male and female neonates and this is associated with a decrease in CD4 count (post vaccination).Keywords: Edo, Delta, Male, Female, Neonates, BCG, CD4, CD

Phytochemical and antibacterial properties of <i>Diodia scandens</i> and <i>Phyllanthus amarus</i> on staphylococci isolated from patients in tertiary hospitals in Nigeria

Background: The rapidly growing use of herbal drugs or supplements in complementary and alternative medicine as substitute for orthodox medicine both in developed and developing countries is fast gaining ground. Aim: This study evaluated both qualitative and quantitative phytochemical constituents of Diodia scandens and Phyllanthus amarus vis-à-vis their synergistic effects on clinically isolated staphylococci. Methods: A total of 200 wounds and burns samples were obtained from patients in the accident and emergency unit of different tertiary hospitals. Staphylococci were isolated and characterised using standard microbiological procedures. Whole plants of D. scandens and P. amarus were Soxhlet extracted with absolute ethanol. The phytochemical analysis was carried out using standard methods. Also, the minimum inhibitory concentration and bactericidal effect of the combined extracts were determined. Results: The phytochemicals present in D. scandens include saponin (6.58%), tannin (2.27 mg/100g), alkaloids (10.53%) and phytin phosphorus (1.80 mg/g), while phytochemicals in P. amarus include saponin (9.99%), tannin (5.82 mg/100g), alkaloids (9.67%) and phytin phosphorus (2.44 mg/g), revealing their antibacterial properties and phytonutrients. The combination study showed that a synergistic effect exists between the two plants on the isolates tested compared with individual extracts alone at the concentrations used. Conclusion: It is noteworthy that the traditional use of these plants was not only confirmed but the combination of D. scandens and P. amarus also proved more effective as antibacterial agent compared with a previous study on the same plants using single determination

Emergence and spread of two SARS-CoV-2 variants of interest in Nigeria.

Identifying the dissemination patterns and impacts of a virus of economic or health importance during a pandemic is crucial, as it informs the public on policies for containment in order to reduce the spread of the virus. In this study, we integrated genomic and travel data to investigate the emergence and spread of the SARS-CoV-2 B.1.1.318 and B.1.525 (Eta) variants of interest in Nigeria and the wider Africa region. By integrating travel data and phylogeographic reconstructions, we find that these two variants that arose during the second wave in Nigeria emerged from within Africa, with the B.1.525 from Nigeria, and then spread to other parts of the world. Data from this study show how regional connectivity of Nigeria drove the spread of these variants of interest to surrounding countries and those connected by air-traffic. Our findings demonstrate the power of genomic analysis when combined with mobility and epidemiological data to identify the drivers of transmission, as bidirectional transmission within and between African nations are grossly underestimated as seen in our import risk index estimates

Molecular studies of the Escherichia coli K5 capsule gene cluster.

Group II K antigens such as the K5 are associated with Escherichia coli causing serious extraintestinal infections. Genes for the production of group II capsules (kps) are organised into three functional regions 1, 2 and 3. The central region 2 encodes proteins involved in the biosynthesis of type specific polysaccharide. Proteins encoded by the flanking regions 1 and 3 are involved in the export of polysaccharide across the bacterial membranes unto the cell surface. Translocation of polysaccharide across the inner membrane is mediated by two region 3 encoded proteins, KpsM and KpsT which belong to the ATP-binding cassette (ABC) superfamily of transporters. Region 1 encodes six proteins, KpsF-E-D-U-C-S. The KpsE protein was shown to localise in the inner membrane and mutants lacking the encoded protein were unable to export polysaccharide to the cell surface. To understand the export role of the KpsE, its membrane topology was determined using TnphoA mutagenesis and beta-lactamase fusions. The topology was confirmed by accessibility of fusion proteins to proteinase K. These results indicated that the KpsE protein adopts a type II bitopic membrane topology consisting of an N-terminus in the cytoplasm followed by a membrane spanning domain, a large periplasmic segment and a C-terminus that may be associated with the outer membrane. On the basis of structural similarity, the KpsE protein is proposed as the membrane fusion protein (MFP) component in the KpsM and T-mediated export of group II capsular polysaccharide and it is postulated to function in the late stages of export across the periplasmic space unto the cell surface. The determined membrane topology contradicts a second C-terminal transmembrane domain in the proposed model based on secondary structure predictions. This points to the importance of experimental data in the establishment of membrane topological models. In addition, the cloning and analysis of a bacteriophage-borne lyase enzyme specific for the E. coli K5 capsular polysaccharide is described. The activity of the K5 lyase enzyme was demonstrated in vitro and its applications are discussed

Seroprevalence of Human Immunodeficiency Virus (HIV) and Hepatitis B Surface Antigen (HBsAg) Among Blood Donors in Central Hospital, Benin City, Nigeria

The prevalence of Human Immoundeficiency Virus and Hepatitis B Surface Antigen among 104 male blood donors in Benin City between the months of August and December 2002 was studied. Serological screening for Anti-HIV antibodies was done using the Immunocomb ll HIV 1 & 2 Bispot test (Orgenics, Israel), while detection of HBsAg was based on the latex agglutination reaction using the Hepatitis B reagent kit manufactured by Quimica Clinica Aplicada, Spain. Four (3.9%) and 11 (10.6%) of the donors screened were positive for HIV and HBsAg respectively. The need for establishing and funding centrally-controlled and monitored blood banking facilities by government is advocated, while efforts should be made to exclude as donors, touts or commercial blood donors known to have high prevalence rates of blood infections. Key words: seroprevalence, HIV, HBsAg, blood donors Journal of Medical Laboratory Science Vol.12(2) 2003: 52 - 5

Prevalence of chlamydia in patients attending gynecological clinics in south eastern Nigeria

Background: Chlamydia infections have been reported to cause silent infections in communities which becomes endemic and could remain unnoticed for a very long time. In most parts of Nigeria these organisms are not screened for, and hence relative information about frequencies of the organisms are sparse. Method: Five hundred and sixty five blood samples and ten umbilical cord fluids were collected from various patients attending clinics in South Eastern Nigeria and were screened for Chlamydia Complement Fixing Antibody (CCFA). Endocervical swabs and urethral discharges or swabs were collected from patients whose serum was positive and were cultured into embryonic eggs which was later observed, harvested and stained using the Romanowsky – Giemsa staining techniques. The positive sera were further confirmed by distinguishing the species of Chlamydia using the monoclonal antibody spot test kit. Result: Of the five hundred and sixty five (565) samples collected only three hundred and forty were positive to CCFA, of which 141 were males and 204 females. From the cultured samples 230 were positive for Chlamydia trachomatis and 99 positive to Chlamydia pneumoniae. Statistical analysis using the student\'s t test at 95% confidence interval shows that there was no significant difference between the number of females and males that presented themselves for screening. Conclusion: Proper screening of patients to include Chlamydia should be encouraged at all levels of medical diagnosis in the country so as to proffer treatment. Otherwise the infection will remain a “silent epidemic”, as is the case currently. Keywords: Chlamydia, Complement fixation test, Chlamydia Complement Fixing Antibody African Health Sciences Vol. 7(1) 2007: pp. 18-2

Cloning, expression, and purification of the K5 capsular polysaccharide lyase (KflA) from coliphage K5A: Evidence for two distinct K5 lyase enzymes

The Escherichia coli K5 capsular polysaccharide [-4)-βGlcA-(1,4)-αGlcNAc-(1-] is a receptor for the capsule-specific bacteriophage K5A. Associated with the structure of bacteriophage K5A is a polysaccharide lyase which degrades the K5 capsule to expose the underlying bacterial cell surface. The bacteriophage K5A lyase gene (kflA) was cloned and sequenced. The kflA gene encodes a polypeptide with a predicted molecular mass of 66.9 kDa and which exhibits amino acid homology with ElmA, a K5 polysaccharide lyase encoded on the chromosome of E. coli SEBR 3282. There was only limited nucleotide homology between the kflA and elmA genes, suggesting that these two genes are distinct and either have been derived from separate progenitors or have diverged from a common progenitor for a considerable length of time. Southern blot analysis revealed that kflA was not present on the chromosome of the E. coli strains examined. In contrast, elmA was present in a subset of E. coli strains. Homology was observed between DNA flanking the kflA gene of bacteriophage K5A and DNA flanking a small open reading frame (ORF(L)) located 5′ of the endosialidase gene of the E. coli K1 capsule-specific bacteriophage K1E. The DNA homology between these noncoding sequences indicated that bacteriophages K5A and K1E were related. The deduced polypeptide sequence of ORF(L) in bacteriophage K1E exhibited homology to the N terminus of KflA from bacteriophage K5A, suggesting that ORF(L) is a truncated remnant of KflA. The presence of this truncated kflA gene implies that bacteriophage K1E has evolved from bacteriophage K5A by acquisition of the endosialidase gene and subsequent loss of functional kflA. A (His)(6)-KflA fusion protein was overexpressed in E. coli and purified to homogeneity with a yield of 4.8 mg per liter of bacterial culture. The recombinant enzyme was active over a broad pH range and NaCl concentration and was capable of degrading K5 polysaccharide into a low-molecular-weight product