Optimization Of Rna Extraction In Mycobacterium Tuberculosis For Studying Intracellular Gene Expression

AOT Alli, JA Mangan, PD Butcher, CL Spreadbury



Mycobacterium tuberculosis is the leading cause of death due to infectious disease after Human immunodeficiency virus. There has been an upsurge in the incidence of tuberculosis since 1980s. In order to reverse this trend, there is need to understand the biology of the organism. This can be brought about by studying gene expression at transcriptional level. The success of this hinges on RNA of good quality. In this paper, five methods (hot phenol, sonication with guanidinium thiocyanate (GTC) solution, beadbeating method with Trizol, FastPrep machine with Divolab as detergent and GTC solution, and FastPrep machine with Trizol) of extracting RNA from bacteria were compared to find
which of the method would be suitable for mycobacteria. The study found that physical method of lysing bacteria was necessary for extraction of RNA from mycobacteria. FastPrep machine gave the highest yield and also provided the speed necessary for optimum RNA extraction. FastPrep and Trizol as reagent for extraction of RNA was applied to macrophage infected with M. tuberculosis (H37Rv) after removing the macrophage RNA. We were able to demonstrate the expression of dnaK gene in both intracellular and broth grown bacilli. The expression of dnaK gene was found to be downregulated in macrophage compared to broth.

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 64-79

Studies On The Distribution Of Clinically Diagnosed Pulmonary Tuberculosis In Ebonyi State, Nigeria

RK Obi, AN Amadi, IM Idika, FC Nwanebu



A study was conducted between January, 2005 to December, 2006 to ascertain the prevalence of pulmonary tuberculosis among patients who attended chest clinics in some randomly selected hospitals, Clinics and Health Centers in Ebonyi State, Nigeria. Investigations were carried out using the two popular diagnostic criteria for pulmonary tuberculosis namely the specific Ziehl Neelsen (ZN) methods and chest X-ray. A total of 962 patients with clinical signs and symptoms of tuberculosis were studied. Out of this figure, 559 (58.1%) had pulmonary tuberculosis with 1:1 male/female ratio. There was no significant difference between ZN sputum smear positive and chest x-ray in the diagnosis of pulmonary tuberculosis in the studied population at 95% confidence level. The possible reasons for the high prevalence of pulmonary tuberculosis may be attributed to increase in the incidence of HIV/AIDS, high rate of poverty, emergence of drug-resistant strains of Mycobacteria and to a lesser extent, smoking and diabetes

Keywords: Pulmonary tuberculosis, sputum, chest X-ray, Ziehl Neelsen

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 80-87

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Sensitivities Of Citrobacter, Proteus And Providencia Isolates To Sulbactam-ampicillin, Trimethoprim-S Ulfamethoxazol And Ticarcillin-Clavulanic Acid Antibiotics

G Uraz, KOK Turhan, HD Binnet



Gram negative bacterias which belong to Enterobacteriaceae family which is critically important as a matter of human health, are comperatively prevalent in nature and foods. Infections formed by bacterias resistant to antibiotics significantly cause mortality and economical losses. Sensitivities of gram-negative bacterias isolated from miscellaneous samples to sulbactamampicillin, trimethoprim-sulfamethoxazol and ticarcillin-clavulanic acid were analysed. In this study, Proteus is primary isolated microorganism with % 52,08. It was determined that Proteus types are proportionally 86,66% sensitive to Trimethoprim-Sulfamethoxazol and 76% resistant to Sulbactam-Ampicillin . Citrobacter is the secondary isolated microorganism (31,25%). It was determined that Citrobacter types were 86,66% sensitive to Trimethoprim-Sulfamethoxazol and % 73,3 resistant to Sulbactam-Ampicillin. Providencia types which are thirdly isolated microorganism (16%), For Providencia types, Trimethoprim-Sulfamethoxazol were determined as the most effective antibiotic again with 86,66% sensitivity. Resistance to Sulbactam- Ampicillin was however, found to be 76%. In conclusion, it is very important to conduct sensitivity tests in choosing antibiotics for chemotherapy of infections. Trimethoprim-Sulfamethoxazol is recommended in the empiric treatment of urinary tract infections in our environment

Keywords: Enterobacter, sensitive, SXT, TĐM, SAM

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 88-91

Candida Species Amongst Pregnant Women In Benin City, Nigeria: Effect Of Predisposing Factors

FE Oviasogie, FI Okungbowa



Genital samples from pregnant women were examined to determine the Candida species present and how some predisposing factors would affect the frequency of isolation of species. A total of 147 women (87 volunteer asymptomatic pregnant women and 60 asymptomatic nonpregnant women) were examined. High Vaginal Swabs (HVS) were collected in pairs while demographic data (age of individual, age of pregnancy, occupation and use of contraceptive pill) on each subject were obtained alongside. Samples were cultured on Sabouraud Dextrose Agar plates and incubated for 72 hours at 37°C. Results revealed five Candida species (C.albicans, C.glabrata, C.tropicalis, C.stellatoidea, C.parapsilosis) with 61.5, 17.9, 7.7, 5.1, 2.6 % frequency of isolation respectively, as against 73.7, 7.7, 1.4, 11.3, and 0.0% for control. Women in the second trimester of pregnancy had the highest occurrence (68.8%) while the age groups 24- 30 and 31-37 years had the highest occurrence in the control (46.2%) and in the pregnant ones (51.7%) respectively. Traders had 68.8%, and full-time housewives, 26.7% occurrence. More women who used contraceptives had Candida (58.3%) as against non contraceptive users (35.3%). The results support literature reports that there are high rates of colonization of the vagina of pregnant women by Candida. They also give credence to earlier reports that the factors determined here affect the frequency of isolation of Candida species from the vagina.

KeywordsCandida, pregnancy, women, genital specimens, Benin City

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 92-98

Risk Factors, Threats And Prevention Of Highly Pathogenic Avian Influenza (HPAI) In African Countries



Highly pathogenic avian influenza (HPAI) is a viral disease that affects the digestive, nervous and respiratory systems of all domestic and wild birds with high morbidity and mortality. It is highly contagious disease which can be fatal in humans. The avian influenza viruses (AIVs) are classified as types A, B and C with 15 subtypes of the type A. To date, all disease causing HPAI Viruses belong to H5 or H7 subtypes; and affect pigs and humans with the pigs serving as a mixing vehicle for re-assortment of the virus. The domestic ducks get infected without showing clinical signs and serve as a source of infection for domestic poultry. Outbreaks of HPAl in Europe, Asia and Turkey are reported to be associated, with the presence of wet lands and lakes where migratory birds rest. In some African countries like Nigeria, such wet lands exist with free flying wild birds and domestic ducks visiting and resting. The possible source of introduction into a country could be through importation or smuggling of infected poultry products across the borders and through migratory birds that fly through identified pathways. The status of HPAl in many African countries including Nigeria is still under investigation so that appropriate strategies / measures to prevent introduction of the disease into the country can be implemented and / or strengthened through restriction of importation of poultry and poultry products from high risk countries, effective disease surveillance, functional National Veterinary services, quarantine and community based participatory epidemiological system for HPAI surveillance and control. This article reviewed the global epidemiology and risk factors of HPAI infection in Nigeria and other African countries with emphasis on specific preventive measures that can reduce introduction of the virus into the country and the epidemiological surveillance for case detection / identification, screening and management. This review provides useful information and updates for health workers in tropical countries on the trends of AIVs and HPAI, diagnostic criteria using case definitions for both community and health facility levels and management protocols for confirmed cases as recommended by the World health Organization.

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp.99-116

Physico-Chemical Quality Of Drinking Water At Mushait, Aseer, South-Western Saudi Arabia

EL Al-Otaibi, MSA Zaki



The physico-chemical quality study of different drinking water sources used in Khamis Mushait, southwestern, Saudi Arabia (SA) has been studied to evaluate their suitability for potable purposes. A total of 62 drinking water samples were collected
randomly from bottled, desalinated and groundwater located around the study area. The parameters determined in this study were Turbidity; Conductivity; Total solids; pH; Chlorides; Hardness; Sulphate; Ammonia; Nitrite; Nitrate; Iron; Manganese;
Copper and Zinc. Most examined parameters were higher in groundwater, followed by desalinated water except for Manganese and Zinc levels. Manganese level was highest in desalinated, followed by bottled water, while Zinc was higher in groundwater
than bottled and desalinated water. Most examined groundwater samples had the highest physico-chemical levels as compared with guideline of international and Saudi standards, followed by desalinated and lastly bottled water. Desalinated water showed the higher Manganese value more than the recommended level followed by bottled water, while all the examined water samples had Zinc content lower than the guideline values of international and Saudi standards. Strict hygienic measures should be applied to improve quality of drinking water and to avoid deleterious effect on human health. This could be achieved by working towards a proper monitoring program of drinking water supply and sources

Keywords: physico-chemical quality, Drinking Water Quality, Khamis Mushait, Saudi Arabia

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 117-127

Sexual Behaviour And Condom Use Among Nigerian Soldiers In Ilorin, Kwara State, Nigeria

NAA Hussain, TM Akande



Background/Objective: Studies have shown that military personnel are aware and knowledgeable about HIV/AIDS and its impact on combat preparedness and efficiency. However, this knowledge did not appear to have translated to reduced risky sexual behaviours. This study, therefore aimed at determining the sexual behaviour and condom use among Nigerian Army personnel in Ilorin, Nigeria. Materials and methods: A descriptive cross-sectional study using a multistage sampling technique to select 400 participants. A pre-tested semi-structured questionnaire was administered. Results: Out of 386 respondents (response rate 96.5%) males constituted 91.2%. Two hundred and
seventy two (70.5 %) were married while 42 (15.4%) of the married did not live with their spouses. A significant proportion of the respondents (45.5%), especially those within the age of 18 to 34 years (p=0.000), those who had participated in foreign military operations (p=0.030) and those who did not live with their spouses (p=0.000) engaged in pre/extramarital sexual activities. Regular condom use among the respondents was low.
Conclusion/Recommendations: There was a high risky sexual behaviour with irregular condom use among the study population. A continuous information, education and communication on HIV/AIDS to effect safe sex behaviours and regular condom use among this population are recommended.

Keywords: Sexual, Behaviour, Condom, Nigerian, Soldiers, Ilorin

African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 128-135