Compression, Mechanical and Release Properties of Chloroquine Phosphate Tablets containing corn and Trifoliate Yam Starches as Binders

Purpose: A study was made of the binding properties of trifoliate yam starch, obtained from Dioscorea dumetorum (Pax), in chloroquine phosphate tablet formulations in comparison with official corn starch. Method: Compressional properties were analyzed using density measurements and compression equations of Heckel and Kawakita. The mechanical properties of the tablets were assessed using the crushing strength and friability of the tablets, while drug release properties of the tablets were assessed using disintegration and dissolution times. Results: Tablet formulations containing trifoliate yam starch exhibited faster onset and higher amount of plastic deformation during compression than those containing corn starch. The crushing strength, disintegration and dissolution times of the tablets increased with binder concentration while friability values decreased. Trifoliate yam starch produced tablets with stronger mechanical properties and longer disintegration and dissolution times than those containing corn starch. Conclusion: Trifoliate yam starch would be a better alternative to corn starch in producing uncoated tablets for which high bond strength is essential . Keywords: Trifoliate yam starch, corn starch, binding agent, compression, Heckel equation, Kawakita equation, mechanical properties, drug release> Tropical Journal of Pharmaceutical Research Vol. 5 (2) 2006: pp. 589-59

Investigation of Some Factors Influencing Corrosion on Refrigerator

The corrosion of steel reinforcing bar can proceed out of sight and eventually result in failure of a section of the highway. The collapse of electrical towers, damage to building, leakages in refrigerator all these result in significant repair cost, endangering public safety and health. This paper presents investigation of some factors influencing corrosion on refrigerator, such as presence of dissolved mineral, organic impurities and dissolved gasses in the water. The survey results are presented using graphs. T-test and Anova were used to ascertain the significance of the factors. The result of alternative Hypothesis and null Hypothesis on the T-test and Anova test were carried out on the factors causing corrosion and responsible for the corrosion were able to be identified. The results revealed that the corrosive effect of fresh water varies from locality to locality due to the wide variety of dissolved impurities, the organism causing the greatest corrosion problems are bacteria and fungi, time of exposure to a corrosive environment influences metal corrosion, most salt solution is good electrolyte and can promote corrosive attack and corrosion effects reduce the life span of refrigerator. The result of this research would guide environmental and material engineers in better planning to minimize corrosion

HYPOGLYCEMIC EFFECT OF TRECULIA AFRICANA DECNE ROOT BARK IN NORMAL AND ALLOXAN-INDUCED DIABETIC RATS.

The solvent partitioned purified fractions of the hydro-acetone root bark extract of the African breadfruit (Treculia africana Decne) were evaluated for hypoglycemic activities in normal and diabetic albino rats. Fasting blood glucose levels were estimated by the use of a glucometer at pre-determined intervals after oral administration of the test extracts/fractions. Results revealed that the test fractions have only a slight effect on blood sugar level of normal rats. On short term and chronic administration in diabetic rats however, diethyl ether-soluble (DEF) and the water-soluble (WSF) fractions significantly reduced the fasting blood sugar levels (

APOE E4 is associated with impaired self-declared cognition but not disease risk or age of onset in Nigerians with Parkinson's disease

The relationship between APOE polymorphisms and Parkinson's disease (PD) in black Africans has not been previously investigated. We evaluated the association between APOE polymorphic variability and self-declared cognition in 1100 Nigerians with PD and 1097 age-matched healthy controls. Cognition in PD was assessed using the single item cognition question (item 1.1) of the MDS-UPDRS. APOE genotype and allele frequencies did not differ between PD and controls (p > 0.05). No allelic or genotypic association was observed between APOE and age at onset of PD. In PD, APOE ε4/ε4 conferred a two-fold risk of cognitive impairment compared to one or no ε4 (HR: 2.09 (95% CI: 1.13-3.89; p = 0.02)), while APOE ε2 was associated with modest protection against cognitive impairment (HR: 0.41 (95% CI 0.19-0.99, p = 0.02)). Of 773 PD with motor phenotype and APOE characterized, tremor-dominant (TD) phenotype predominated significantly in ε2 carriers (87/135, 64.4%) compared to 22.2% in persons with postural instability/gait difficulty (PIGD) (30/135) and 13.3% in indeterminate (ID) (18/135, 13.3%) (p = 0.037). Although the frequency of the TD phenotype was highest in homozygous ε2 carriers (85.7%), the distribution of motor phenotypes across the six genotypes did not differ significantly (p = 0.18). Altogether, our findings support previous studies in other ethnicities, implying a role for APOE ε4 and ε2 as risk and protective factors, respectively, for cognitive impairment in PD

Antimicrobial and Pharmaceutical Properties of The Seed Oil of Leucaena leucocephala (Lam.) De Wit (Leguminosae)

The seed oil of Leuconia leucocephala was investigated for its antimicrobial activity and the pharmaceutical properties of its lotion formulation determined. The oil was extracted from the pulverised dried seeds of the Leuconia leucocephala plant by cold maceration in n-hexane. The oil was tested against four bacteria ( Staphylococcus aureus , Esherichia coli , Bacillus subtilis and Pseudomonas aeruginosa ) and four fungi ( Aspergilus niger , Rhizopus stolon , Penicillum notatum and Candida albicans ) isolates. Gentamycin and tioconazole were the reference drugs respectively. The oil was later formulated as a lotion and the pharmaceutical properties of the formulation determined.The oil was found to have a concentration-dependent activity against both Gram-positive and Gram-negative bacteria, while showing no activity against the fungi tested. The lotion formulation of the oil containing oleic acid had good pharmaceutical properties and was stable over the test period. Leucaena leucocephala seed oil extract had a concentration-dependent activity against both Gram-positive and Gram-negative bacteria and the lotion formulation had good pharmaceutical properties

Hypoglycemic Effect Of Treculia Africana Decne Root Bark In Normal And Alloxan-Induced Diabetic Rats

The solvent partitioned purified fractions of the hydro-acetone root bark extract of the African breadfruit ( Treculia africana Decne) were evaluated for hypoglycemic activities in normal and diabetic albino rats. Fasting blood glucose levels were estimated by the use of a glucometer at pre-determined intervals after oral administration of the test extracts/fractions. Results revealed that the test fractions have only a slight effect on blood sugar level of normal rats. On short term and chronic administration in diabetic rats however, diethyl ether-soluble (DEF) and the water-soluble (WSF) fractions significantly reduced the fasting blood sugar levels (p<0.05) at differing rates when compared with the control group of animals. The diethyl ether soluble fraction (10 mg kg-1 dose level) was found to exhibit the highest activity giving 69.4% reduction in blood sugar level (at 240 hours) which was in comparable range with the reference standard glibenclamide (0.5 mg kg-1) which reduced blood sugar levels by 65.8% below the initial baseline values

Evaluation of Mucoadhesive Properties of Native and Modified Starches of the Root Tubers of Cocoyam ( Xanthosoma sagittifolium )

The purpose of this study was to evaluate the bioadhesive properties of native and modified cocoyam ( Xanthosoma sagittifolium ) starches. The methods of modification were by pregelatinisation and acetylation. The starch particles were evaluated for characteristics like particle size, swelling ability, viscosity, and mucoadhesion. The mucoadhesive evaluation of the starches were done using the rotating cylinder methods in 0.1M HCl and Phosphate buffer (pH 6.8) to simulate the stomach and small intestine respectively. The mechanical properties of the compacted starches were determined using friability and crushing strength.The particles so prepared had irregular shape size ranged from 9.38 to 10.67mm. Mucoadhesion time was in the order Acetylated >Native >Pregelatinised starch in 0.1M HCl and Pregelatinised >Native >Acetylated starch in pH 6.8 Phosphate buffer. None of the severe signs such as appearance of epithelial necrosis, sloughing of epithelial cells were observed in ileum sections. The work concludes that modified cocoyam starches could be useful in targeted mucoadhesive drug delivery

Production Characteristics, Activity Patterns and Biodecolourisation Applications of Thermostable Laccases from <em>Corynebacterium Efficiens</em> and <em>Enterobacter Ludwigii</em>

562-569The production conditions, characteristics and dye decolourisation potentials of two purified bacterial laccases from Corynebacterium efficiens and Enterobacter ludwigii were investigated. Optimum production pH was 3.0 and 4.0 respectively for E. ludwigii and C. efficiens. Khaya sp. and Gmelina arborea wood shavings, (NH4)2SO4 (30.2&micro;M/ml) and K+ maximally supported laccase production in both organisms. The Vmax and specificity constants for both purified laccases were 44.6&micro;M/mg; 1858.4S-1&micro;M-1and 23.15&micro;M/mg; 1015.4S-1&micro;M-1 respectively. Maximum laccase activity was between 80&deg;C and 90&deg;C and pH 7.0. In both laccases, Fe3+ induced higher activity and red Dylon dye was 69% and 64% decolourised. The properties exhibited by these laccases could enhance their suitability in diverse biotechnological applications