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BACKGROUND: Previous folkloric and experimental reports have demonstrated the antimalarial efficacy of Azadirachta indica (AZA) extracts. However, one of the major challenges facing its application for the clinical treatment of malaria is the design of an acceptable dosage form. OBJECTIVE: Consequently, we developed AZA extract-loaded nanostructured lipid carriers (NLC) for the formulation of suppositories, denoted as nanosuppositories, for intrarectal treatment of malaria. METHODS: Various batches of NLC-bearing AZA extract were formulated based on lipid matrices prepared using graded concentrations of Softisan®154 and Tetracarpidium conophorum or walnut oil. NLC was investigated by size and differential scanning calorimetry (DSC). Suppository bearing AZA extract-loaded NLC was developed using cocoa butter or theobroma oil, and their physicochemical properties were profiled. In vitro drug release and in vivo antimalarial activity (using Plasmodium berghei-infected mice) were investigated. RESULTS: NLCs exhibited sizes in nanometers ranging from 329.5 - 806.0 nm, and were amorphized as shown by DSC thermograms. Nanosuppositories were torpedo- or bullet- shaped, weighing 138 - 368 mg, softened/liquefied between 4.10 - 6.92 min, and had controlled release behaviour. In vivo antimalarial study revealed excellent antimalarial efficacy of the nanosuppositories comparable with a commercial brand (Plasmotrim®) and better than the placebo (unloaded nanosuppository), and without toxic alterations of hepatic and renal biochemical factors. CONCLUSION: Thus, AZA extract could be rationally loaded in nanostructured lipid carriers (NLC) for further development as nanosuppository and deployed as an effective alternative with optimum convenience for intrarectal treatment of malaria.

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PURPOSE: To assess the improvement in oral bioavailability and efficacy in systemic candidiasis treatment of miconazole nitrate (MN) formulations in murine models of candidiasis. METHODS: Selected formulations containing 5% of Softisan + Phospholipon 90H lipid matrix with 3% of MN (A 1), 5% of stearic acid + Phospholipon 90H lipid matrix with 3% of MN (B 1), and 5% Softisan + stearic acid + Phospholipon 90H with 3% of MN (C 1) from the in vitro investigation were used for the study. Their acute toxicity was assessed using Lorke's method (with slight modification) while bioavailability was determined using the bioassay method. The optimized batch (A 1) was tested in murine systemic candidiasis induced in cyclophosphamide-immunosuppressed mice. The mice were treated with a single oral dose (100 mg/kg) of the formulations for five days. Serum fungal counts (cfu/mL) were determined on days 1, 3, and 5 of the treatment period. Haematological assessments were done. RESULTS: The lipid formulations were safer than MN powder with LD50 values of 3162.8 and 1118.3 mg/kg. Bioavailability determination revealed a higher area under the curve (AUC) value for formulations A 1 (6.11 µg/hr/mL) and B 1 (4.91 µg/hr/mL) while formulation C 1 (1.80 µg/hr/mL) had a lower AUC than MN (4.46 µg/hr/mL). Fungi were completely cleared from the blood of animals treated with the optimized formulation by day 3 as opposed to the controls (MN and Tween® 20) which still had fungi on day 5. No significant increase (p > 0.05) in haematological parameters was observed in mice treated with A 1. CONCLUSION: Formulation A 1 successfully cleared Candida albicans from the blood within a shorter period than miconazole powder. This research has shown the potential of orally administered MN-loaded SRMS-based microparticles in combating systemic candidaemia.

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Purpose: Biosurfactants are applied in drug formulations to improve drug solubility and in some cases, treat diseases. This study is focused on generating, extracting, purifying and then characterizing biosurfactants from bacterial isolates of palm oil wastes and abattoir soil origins. Methods: Eight bacteria were isolated from the soil and sludge samples, out of which four (50%) were found to produce biosurfactants. Bacillus subtilis (37.5%) and Pseudomonas aeruginosa (50%) were isolated and identified from these samples using mineral salt medium, nutrient agar and Cetrimide agar. Mutant isolates of B. subtilis BS3 and P. aeruginosa PS2 were used to produce biosurfactants using mineral salt medium as enrichment medium and extraction was done using membrane filter. Results: The mutant strains B. subtilis BS3 and P. aeruginosa PS2 generated biosurfactants that displayed significant solubility and dissolution properties by enhancing the percentage solubility of piroxicam to 62.86 and 54.29% respectively, and achieved 51.71 and 48.71% dissolution of the drug in 0.1N HCl. Conclusion: From the results obtained, the produced biosurfactants could serve as a better alternative to conventional surfactants. Notably, the study indicated that the biosurfactant produced by mutant strain of B. subtilis produced more potent activities (surface tension reduction ability, high emulsification) than those of P. aeruginosa.

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BACKGROUND: Pneumonia is an acute or chronic inflammatory disorder of the lungs, affecting the mucosal areas of the lung. It can be caused by bacteria, viruses or fungi. In some cases, it may be caused by physical or chemical irritants. Kolaviron, a natural bioflavonoid extract from Garcinia kola seeds, has been shown to possess anti-inflammatory properties in Flu-like conditions which are associated with cough. There has been a paucity of information on the likelihood of the effectiveness of kolaviron against pneumonia infections. OBJECTIVE: To evaluate the antibacterial and anti-inflammatory effects of kolaviron on albino Wistar rats induced with pneumonia using Klebsiella pneumonia. MATERIALS AND METHODS: Powdered Garcinia kola seeds were extracted with n-hexane and 100% methanol as solvents by using Soxhlet extractor. A standard method was used to obtain kolaviron from the seed extracts. A total of 24 albino Wistar rats were randomly divided into six groups A to F, each comprising four rats. The rats were allowed to acclimatize for 1 hour in very cold environments using ice packs. A standardized 1.0 x10 -5 mg/ml culture suspension was intranasally inoculated to the rats for 10 days to induce pneumonia-like symptoms. Thereafter, the kolaviron was administered to the rats such that a 500mg/kg kolaviron extract was given once daily to groups A (male rats) and B (female rats). Groups C (male rats) and D (female rats) received 250mg/kg of kolaviron extract once daily, while group E rats were given 0.5 ml of dimethyl sulfoxide (DMSO) once daily, which served as the negative control. The rats in Group F received 2.86 mg/kg of ofloxacin once daily and served as the positive control. All the treatments were done for a period of 5 days. Then 10 days after the treatments, the animals were sacrificed and the lungs were harvested for hydrostatic lung test and histopathological examination. An overnight broth culture of Klebsiella pneumonia was streaked in sterile molten nutrient agar maintained at 37°C for 24hrs. Later, a stock of 500mg/ml of kolaviron was prepared in DMSO. Two-fold dilutions were performed to obtain the following concentrations of 100%, 50%, 25%, 12.5%, 6.25%, 3.125%, and 1.565% with the stock. The anti-Klebsiella pneumonia activity of the kolaviron extract was determined using agar well diffusion methods and incubation was done at 37 o C for 24 hrs. Student t-test and Oneway Analysis of variance (ANOVA) were used for comparison of mean differences between and among the groups. RESULTS AND DISCUSSION: The sensitivity of Klebsiella pneumonia to kolaviron was concentration- dependent. There was an increase in anti-Klebsiella pneumonia activity with a decrease in kolaviron concentration. Kolaviron (KV), at 500mg/kg concentration, was efficacious and showed significant anti-inflammatory effects (P<0.0001). This was also confirmed in the histopathological examinations. The 3.125% concentration of the kolaviron gave IZDs that ranged from 25.68±3.33 mm on day 1 to 27.33±2.78 mm on day 5. Treatment with kolaviron showed to be sex-dependent with a significant difference (p<0.0001), when pre-treatment and post-treatment effects were compared between male and female rats. CONCLUSION: Kolaviron can be used as an agent in the treatment of pneumonia as it possesses anti- inflammatory and anti-Klebsiella pneumonia activities.

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Self-nanoemulsifying formulations (SNEFs) structured with PEG 4000 as PEGylated SNEFs, were formulated after solubility studies using rational blends of soybean oil, a combination of Kolliphor(®) EL and Kolliphor(®) P188 as surfactants, and Transcutol(®) HP as co-surfactant, and evaluated for oral delivery of gentamicin. Incorporation of gentamicin and PEG 4000 reduced the initial area of nanoemulsion of the ternary phase diagrams produced by water titration method using oil, surfactant mixture and co-surfactant. Emulsion droplets were in the nanometer scale ranging from 80-210 nm. FT-IR study revealed that gentamicin structure remained intact in all formulations, and SEM micrographs showed spherical globules. Zeta potentials of SNEFs were in the range of -25.4 to -42.5 mV, and showed a stable system with minor flips in electrostatic charges. There was high in vitro diffusion-dependent permeation of gentamicin from the SNEFs. Results obtained in this work showed that oral delivery of gentamicin was improved by formulation as surface modified SNEFs.

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