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A new family of outwardly rectifying potassium channel proteins with two pore domains in tandem.
Potassium channels catalyse the permeation of K+ ions across cellular membranes and are identified by a common structural motif, a highly conserved signature sequence of eight amino acids in the P domain of each channel's pore-forming alpha-subunit. Here we describe a novel K+ channel (TOK1) from Saccharomyces cerevisiae that contains two P domains within one continuous polypeptide. Xenopus laevis oocytes expressing the channel exhibit a unique, outwardly rectifying, K(+)-selective current. The channel is permeable to outward flow of ions at membrane potentials above the K+ equilibrium potential; its conduction-voltage relationship is thus sensitive to extracellular K+ ion concentration. In excised membrane patches, external divalent cations block the channel in a voltage-dependent manner, and their removal in this configuration allows inward channel current. These attributes are similar to those described for inwardly rectifying K+ channels, but in the opposite direction, a previously unrecognized channel behaviour. Our results identify a new class of K+ channel which is distinctive in both its primary structure and functional properties. Structural homologues of the channel are present in the genome of Caenorhabditis elegans
Optimization of a Novel Oral Colon Delivery System of Indomethacin Using Full Factorial Design
Purpose: To develop and optimize indomethacin (IDM) matrix tablets for specific colon drug delivery.Methods: Indomethacin matrix tablets containing hydrogenated castor oil (HCO), and pectin (PEC) were prepared by hot fusion method. A 32 full factorial design was used to investigate the combined effect of two independent formulation variables, X1 and X2, namely, the amount of HCO and PEC, respectively. Their effect on IDM release from the matrix tablets in acidic medium (0.1 N HCl) and phosphate buffer (pH 6.8), were analyzed and optimized. A contour plot was also applied to graphically represent the effect of the independent variables on drug release in pH 6.8 medium at 2 h (Y1) and 24 h (Y2), and the time required for 25 % drug release (Y3) as dependent variables.Results: The optimized IDM matrix tablets showed almost total retardation of drug release in acidic medium and prolonged sustained release in pH 6.8 medium over 24 h. The correlation coefficient (R2) value for Y1, Y2 and Y3 were 0.99850, 0.9980 and 0.9970, respectively, indicating good correlation between dependent and independent variables. Differences between the coefficients for Y1, Y2 and Y3 were significant (p < 0.05), and hence contributed significantly to the prediction of the independent variables.Conclusion: The findings indicate that successful design, development, and optimization of IDM matrix tablets for colon delivery has been achieved.Keywords: Indomethacin, Hydrogenated castor oil, Pectin, Factorial design, Matrix tablets, Colondelivery syste
Fire extinguishing strength of the combustion product of wood saw dust (ash)
Forty saw dust samples from four mature hard wood plants grown in southwestern part of Nigeria were analyzed for their ash contents, moisture contents, metallic contents and hence the fire extinguishing strength of the saw dust ash by classical and instrumental methods of analyses. Mahogany (Khaya ivorensis) wood saw dust ash had the highest mean metallic content (5.989±2.51ppm) followed by Opepe (Sarcocephalus latifolius) , 4.704±0.21ppm while Poro poro (Sorghum bicolour) wood ash had the least metallic content (1.611±0.48ppm). Mahogany also had the highest mean moisture content (2.6615±0.64) while Opepe had the least moisture content (0.9362±0.45). The fire extinguishing strength of Mahogany was the highest, and had a positive correlation with its metallic content as depicted by their correlation coefficient (0.850). Poro poro had the least fire extinguishing strength. The comparison of the extinguishing strength of wood saw dust samples and the commonly used ABC fire extinguisher showed that ABC fire extinguisher has more extinguishing strength than the wood saw dust ash. Hence, improvement on the extinguishing strength of the saw dust ash is necessary. © JASE
Effect of different rates and methods of benomyl and mancozeb application on delay in senescence and grain yield of cowpea (Vigna unguiculata (L) Walp) under different cropping season
Field assessment of different rates and methods of three fungicide applications on delay in senescence (DS) and grain yield of cowpea during the early and late cropping season of 1999 respectively was conducted. The benomyl treatment applied via the combination of seed and foliar methods at the highest rate of 0.75 + 0.75kg a.i/ha gave the highest percentage delay in senescence (100%) as well as highest grain yield of (2.1 t/ha) which were significantly different (
Perceptions, Experiences and Expectations of Physicians Regarding the Role of the Pharmacist in an Iraqi Hospital Setting
Purpose: To investigate the perceptions, expectations, and experiences of physicians regarding hospital-based pharmacists in some Iraqi government hospitals.Methods: A cross-sectional study was conducted at four government hospitals in Baghdad and Erbil, Iraq from March to July 2012. A validated, self-administered questionnaire was hand-delivered to a random sample of 200 physicians. The questionnaire comprised four sections that probed the physicians' demographic characteristics as well as their perceptions of, expectations of, and experiences with hospital pharmacists.Results: Most participants (69.4 %) reported rarely interacting with pharmacists and that enquiring about the availability of medications was the main purpose (74.9 %) of any interactions. Physicians reported being comfortable with pharmacists preventing prescription error, treating minor illness, and suggesting prescription medication to physicians of 74, 75 and 67 %, respectively, but only 47 % were comfortable with pharmacists providing patient education. The perspective of physicians in Erbil differed from that of physicians in Baghdad (p < 0.05).Conclusion: Interactions between Iraqi physicians and pharmacists are still not optimal. Physicians are much more comfortable with traditional pharmacist functions than with the extended, patient-oriented pharmacy services currently being promoted. Great efforts are needed to enhance the Iraqi physician's attitude regarding the clinical services provided by pharmacists which in turn would result in more collaboration among healthcare professionals.Keywords: Physician, Pharmacist, Perception, Experience, Expectation, Patient-oriented, Pharmacy servic
A Rare Case of Immature Ovarian Teratoma with Gliomatosis Peritonei
Gliomatosis peritonei (GP) is a rare condition that occurs almost exclusively in the setting of ovarian immature teratoma. It is characterisized by the occurrence of nodules of mature glial tissues in the peritoneum, omentum and bowel wall. The glial tissue in such cases is usually low grade although there have been cases of malignant evolution described. In general, the prognosis for GP is good. It depends chiefly on the degree of maturity of the implants. In mature GP, usually no additional chemotherapy is necessary. In immature GP, chemotherapy can induce maturation of the implants. We present a case of immature ovarian teratoma associated with low grade GP.Keywords: Glial tissue, gliomatosis peritonei, immature teratoma, India, ovar
The micro-minerals composition in serum of rabbits (Oryctolagus cuniculus) infected with Trypanosoma congolense
Sixteen (16) rabbits aged between 6 to 12 months were infected with fresh stock of Trypanosoma congolense (Gboko strain) intravenously at the rate of 1.0 × 106ml. Animals were classified into two groups; groups A were infected, while group B served as uninfected controls. Samples from the infected and the uninfected controls showed a significant increase in the levels of sodium (Na+), calcium (Ca2+), phosphate (PO4 2-) and blood urea nitrogen (BUN) (P < 0.05) and a significant decline in the levels of potassium (K+) and bicarbonate (HCO3 2-) (P < 0.05). Therefore, the alterations in the compositions of these micro-minerals in the serum of rabbits may suggest that, they could have a role in the pathogenesis of trypanosomosis due to T. congolense infection.Key words: Rabbits, micro-minerals, Trypanosoma congolense, pathogenesis
Seismic refraction investigation of the subsurface structure at the southern part of Niger State College of Education, Minna, Nigeria
This paper discussed the seismic refraction survey conducted at the southern part of Niger State College of Education Minna, in which a three-channel seismograph was used for the survey. The profiles were marked at 100m intervals, while the profiles lines traversed 1000m (1km). The exact site surveyed covers a total area of about 500,000m2. From the data collected, time – distance curves for each shot points were drawn, the velocities of the underlying layers for each points were obtained and the depths to the refractor layer were computed. The results obtained gave an overview of the lateral variation in the lithological changes of the subsurface earth materials in the surveyed area. The basement surface varied in depth, from depths as shallow as 2.05m to a maximum of 10.13m. The rock materials identified in the surveyed area are chiefly sand, saturated clay, gravel, and granite.
Keyword: Basement, aquifer, Seismograph, time-distance curve, and velocity
Phylogenetic diversity and relationships among 40 rice accessions using morphological and RAPDs techniques
Morphological characterization of 40 rice accessions using 14 agro-botanical traits was done in a field experiment in an augmented randomized complete block design. The aim of the work was to study variations and to select lines that can be used as potential parents in a future breeding program. The single linkage clustering, the Principal Components Axes and a morphological dendrogram were used to group the accessions. Genetic relatedness among accessions based on random amplified polymorphic DNA (RAPD) molecular marker data was also presented in form of a dendrogram using the Unweighted Pair Group Method with Arithmetic mean (UPGMA). Relative effectiveness of the RAPD markers and genetic diversity among accessions as revealed by botanical descriptors were compared.The single linkage cluster technique classified the 40 accessions into six morphological groups whereas the PCA re-ordered the accessions into four broad groups that had within cluster similarities and inter-cluster morphological variations. RAPDs were highly polymorphic, more discriminatory and informative as they were able to differentiate more pairs of accessions than the botanical descriptors. IITA rice accessions TOX 3052-46-3-3-2-1 and TOX 3027-44-1-E4-2-2 and Brazilian accessions (CLSELECCION 3B and 450) that performed better than checks could be selected for a future breeding program
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