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The efficacy of repeated doses of Dinazene® in Albino rats experimentally infected with Trypanosoma brucei (Gboko strain) was investigated. A total of 30 adult female Albino rats weighing 130-190 g were used for the study. They were assigned to six groups (groups A-F) of five rats each. Groups A-D were infected intraperitoneally with 1.0 ? 106 trypanosomes in 400 µL of PBS diluted blood while groups E (uninfected treated) and F (uninfected untreated) served as controls. The rats in the groups A-D as well as those in group E were treated with 7.0 mg/kg body weight at day 11 post infection. Groups B, C and D however received two, three and four repeated doses of the drug at weekly intervals following initial treatment. There was complete clearance of the parasite within 120 h post treatment. Parasitaemia, packed cell volume (PCV), total red blood cell (RBC) and white blood cell (WBC) counts, haemoglobin concentration (Hb), rectal temperature, and body weight were used to assay the efficacy of treatment. Following treatment and parasite clearance from the blood, there was improvement (P<0.05) in the values of parameters measured when compared to the uninfected controls. However, relapse infection was observed in the rats of group A, B and C, with a resultant decline in clinical condition and values of parameters used to assess efficacy. We concluded that four consecutive treatments using same dose at weekly intervals proved efficacious in the experimental management of T. brucei infection in rats. [ABSTRACT FROM AUTHOR]

Chromium pillared bentonite clay was prepared by cation exchange reaction of the clay with a solution of chromium nitrate. Its capacity to adsorb heavy metal ions (nickel and lead) from solutions were studied in a batch adsorption system. The result showed that the amount of metal ions adsorbed was totally dependent on metal ion concentration, contact time and pH of the solution. This investigation also showed that the maximum sorption of the heavy metals occurred within 40 minutes at pH of 4-6. The uptake of the metal ions followed second order kinetics. The interactions of the heavy metal ions with the solid adsorbent showed a decrease in entropy and appreciable decrease in Gibbs free energy indicating a spontaneous sorption process. The results have demonstrated good potentiality for chromium pillared bentonite to remove heavy metal ions from aqueous solutions and polluted waters. [ABSTRACT FROM AUTHOR]

Farmers in south-eastern Nigeria depend greatly on cassava for its many products. The production however is beset with a myriad of constraints of which the rural farmers despite the influx of modern scientific knowledge still carry out indigenous production practices. Recently the Farmer Field School (FFS) strategy has come to fore, with a view to up-scaling Indigenous Knowledge (IK) to scientific knowledge. This study used the FFS approach to compare improved and indigenous cassava production practices. The study was carried out in Owerri North Local Government Area, Eastern part of Nigeria. Data were collected with the aid of structured questionnaire. 100 respondents were randomly selected from the study area. Descriptive statistics was applied in the data analysis. At the end of the 1st year planting season of 12 months, yield of cassava on Integrated Pest Management (IPM) plot of 1 ha was 33 t of cassava. Using farmers' local cassava variety, farmers' plot of 1 ha gave a total yield of 8 t of cassava. Finally, in the 2nd planting season yield on the farmers' plot using improved cassava variety gave a total yield of 18 t, while the IPM plot was 34 t. It was recommended therefore that farmers can improve on yield if they include some of the IPM practices in addition to the use of improved cassava varieties as was carried out in the FFS which is an effective and, bottom-top, participatory method of technology transfer. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine the genetic relatedness of strains isolated from diarrhoeal stool and water specimens collected from water-storage containers from different geographical areas in the Limpopo province. In total, 32 Aeromonas strains isolated from stool specimens collected from HIV/AIDS patients suffering from gastroenteritis and their household drinking-water stored in 20-L and 25-L containers were analyzed by random amplified polymorphic DNA PCR (RAPD). The RAPD fingerprints obtained proved reproducible when repeated on three different occasions using whole-cell DNA isolated from the Aeromonas strains. In total, 12 unique RAPD fingerprints were found. The results revealed a tendency of the isolates to cluster according to their origin of isolation (best-cut test 0.80 and bootstrap values >50%). However, a certain degree of similarity was also observed between isolates of water sources and clinical sources which indicated genetic relatedness. There were also genetic similarities between the clinical and the environmental strains of Aeromonas spp. isolated from different geographical areas. This study has demonstrated the genetic relatedness of Aeromonas hydrophila isolates from household drinking-water and clinical sources in South Africa, which may be due to cross-contamination from water to patients or vice-versa. This observation is of public-health significance, particularly in the era of HIV/AIDS. This study points to the importance of monitoring and evaluating infection-control measures for improved hygiene and to prevent cross-contaminations. [ABSTRACT FROM AUTHOR]

Multidrug-resistant tuberculosis (MDR-TB) has been a cause of concern in both developed and developing countries. The prevalence of drug resistance in Mycobacterium tuberculosis (MTB) isolates (n=692) from Mpumalanga province was assessed. In total, 692 (64%) MTB strains from cases with pulmonary TB were tested for susceptibility against rifampicin, isoniazid, ethambutol, and streptomycin using the MGIT 960 instrument. Two hundred and nine (30.2%) strains were resistant to one or more drugs. Resistance to one drug ranged from 1.4% for ethambutol to 17.7% for rifampicin. The prevalence of MDR-TB ranged from 6.7% for three drugs to 34% for four drugs, with significant predictors being patients' age-groups of 25-54 years (p=0.0012) and >55 years (p=0.007). The result showed a high level (58.4%) of MDR-TB from cases in Mpumalanga province. To achieve a higher cure rate in this province, drug-susceptibility tests must be done for every case. [ABSTRACT FROM AUTHOR]

A survey involving 181 water treatment plants across 7 provinces of South Africa: Mpumalanga, Limpopo, North West, Free State, KwaZulu-Natal, Eastern Cape and Western Cape was undertaken to identify the challenges facing small water treatment plants (SWTP5) in South Africa. Information gathered included ownership and design capacity of the plants, water sources, and various methods of disinfection, equipment currently employed and performance of the treatment plants. In general, the majority (over 80%) of the SWTPs surveyed in the designated provinces were owned by the district municipalities. The designed capacities of these plants varied between 1 and 60 Mℓ/d; the smallest capacity was 100 mℓ/d and the largest 120 Mℓ/d. The small water treatment plants abstracted their raw water from either surface or groundwater or a combination of both water sources with greater preponderance for surface water sources (over 86%). Water treatment practices were noted to be the conventional types mainly coagulation, flocculation, sedimentation, filtration and disinfection. Two types of coagulants namely polyelectrolyte (66%) and alum (18%) were commonly used by the water treatment plants across the provinces studied. Rapid gravity filtration, pressure filter and slow sand filtration systems accounted for 60%, 23% and 9% of the filtration systems across the provinces, respectively. The predominant types of disinfectants employed were chlorine gas (69%) followed by sodium (15%) and calcium (14%) hypochlorite. Over 50% of the various SWTPs did not comply with the SANS 241 Class I (< I NTU) and Class II(1 to 5 NTU) recommended turbidity values. The recommended target range of 0.3 to 0.6 mg/ℓ free chlorine residual concentrations at the point of use was not always met by 40% of the plants. Seventy percent of the SWTPs complied with the SANS 241 criteria of microbiological safety of drinking water vis-á-vis total and faecal coliforms. Operational problems affecting the efficiency of small water treatment plants included: inability to appropriately determine the flow rate, chemical dosage and turbidity, lack of chlorine residual at the point of use and lack of water quality monitoring. To produce safe drinking water, appropriate operational practices must be implemented in all small water treatment plants. [ABSTRACT FROM AUTHOR]

In an endeavour to ascertain the interplay of factors involving chlorine dose, turbidity and flow capacity on microbial quality of drinking water in small water treatment plants (SWTPs), data from a previous study were analysed. The findings showed that most of the SWTPs were not producing water of safe microbial quality. Fifty one percent (51%) and seventy three (73%) of the SWTPs were below the stipulated limits for residual chlorine in final water and water at the point of use respectively. Current flow capacity was a major determinant of the microbial water quality indicators but no association was found between the dose of chlorine used for water treatment and the microbial water quality indicators. However, a combination of the amount of chlorine dose used up during treatment, flow capacity and change in turbidity contributed to about 65% of the amount of heterotrophic plate counts removed from raw water. Current flow capacity contributed less than 14% of the variation in chlorine dose used in water treatment at the plants. Turbidity tended to correlate and contribute more to the prediction of total coliform counts while faecal coliform counts were determined by current flow capacity and conductivity. Treatment plants with current flow capacity of over 50 Ml/d tended to be more efficient in heterotrophic plate count removal. In conclusion, this study noted that most of the SWTPs were using a chlorine dosage that was below the amount required by their respective current flow capacity; possible micro-organism resistance to chlorine and the significant effect of the level of turbidity on the microbial quality of treated water. [ABSTRACT FROM AUTHOR]

The prevalence, pathogenic indices, such as haemolytic and haemagglutinating activities, antibiograms, and in-vitro activities of local medicinal plants against Aeromonas isolates in Vhembe district of Limpopo province, South Africa, were studied using standard microbiological methods. In total, 309 diarrhoeic stool samples were collected from patients attending five health centres in the region during December 2004-May 2005. Aeromonas species were identified using the API 20E system. The haemagglutinating and haemolytic activities of isolates on human, sheep, pig and chicken red blood cells were investigated. Antibiotic susceptibility profiles of the isolates to several antibiotics and in-vitro activity of local medicinal plants were also ascertained using previously-reported schemes. Results showed that 104 (33.6%) of the 309 samples were positive for Aeromonas species, of which 89 (85.6%) were Aeromonas hydrophila, 12 (11.5%) A. sobria, and three (2.9%) A. caviae. All strains of A. hydrophila and A. caviae produced haemolysis on sheep blood, while eight of the 12 A. sobria strains were haemolytic on sheep blood. The haemolytic activities of the isolates were variable on other red blood cells tested. High level of resistance was observed to amoxicillin and ampicillin, followed by cefuroxime (79%), chloramphenicol (74%), and erythromycin (65%). The carbapenems were the most active drugs with only 7% resistance to meropenem and 11% to imipenem. About 12% of the isolates were resistant to ciprofloxacin. The extracts of three of seven medicinal plants tested showed inhibitory activity against all Aeromonas isolates; these included acetone and hexane extracts of Pterocarpus angolensis, Syzygium cordatum, and Zornia milneana. The results suggest a high prevalence of Aeromonas species in the region. The isolates demonstrated multiple resistant profiles to different antibiotics tested. Some local medicinal plants were inhibitory to Aeromonas isolates, indicating a potential role in the management of Aeromonas-related infections. Structural elucidation of the active components may pave the way for the discovery of candidate templates for eventual drug design. Most isolates possessed important virulence characteristics based on their haemolytic and haemagglutinating ability. However, the genetic characterization of the isolates will further confirm their pathogenicity and the origin of multiple antibiotic resistance. [ABSTRACT FROM AUTHOR]