Journal Article

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DNA synthesis in prokaryotes: Replication
(1973) Smith DW
Gm1 Ganglioside β-Galactosidase A: PURIFICATION AND STUDIES OF THE ENZYME FROM HUMAN LIVER
(1974) Norden AG; Tennant LL; O'Brien JS
Gm1-ganglioside β-galactosidase A (EC 3.2.1.23) has been purified 17,000-fold from human liver. The enzyme appeared as a single band of protein on polyacrylamide gel electrophoresis. Double immunodiffusion of rabbit anti-β-galactosidase A antiserum against either Gm1 β-galactosidase A or liver supernatant gave a single precipitin band. The apparent molecular weight was 65,000 to 75,000 by gel filtration of the native enzyme and 72,000 by sodium dodecyl sulfate gel electrophoresis of the denatured, reduced, and carboxymethylated enzyme. The purified enzyme liberated d-galactose from synthetic chromogenic and fluorogenic β-d-galactosides, as well as lactose, N-acetyllactosamine, and the glycoprotein asialofetuin. The same catalytic site(s) appeared to be responsible for the hydrolysis of Gm1-ganglioside and 4-methylumbelliferyl-β-d-galactopyranoside. The enzyme also cleaved β-d-fucoside and α-l-arabinoside linkages. Lactulose, galactosyl-hydroxylysine, galactosyl-hydroxylysyl peptides, galactocerebroside, lactosylceramide, and monogalactosyldiglyceride were very poor susbtrates. Anti-β-galactosidase A antiserum quantitatively precipitated both β-galactosidase A and β-galactosidase B. Neutral β-glucosidase (“nonspecific” β-galactosidase), galactocerebroside β-galactosidase, and lactosylceramide β-galactosidase were not precipitated by anti-β-galactosidase A antiersum.
Peptide inhibition of myointimal proliferation by angiopeptin, a somatostatin analogue
(1991) Lundergan CF; Foegh ML; Ramwell PW
Vascular smooth muscle cell hyperplasia is a major component of atherogenesis in various animal models. Angiopeptin, a cyclic octapeptide analogue of somatostatin, markedly inhibits myointimal proliferation in response to endothelial cell injury in the rat carotid artery, rabbit aorta and iliac arteries and in coronary arteries of transplanted rabbit hearts. Angiopeptin does not affect serum lipid profiles in nonhuman primates. It is unlikely, therefore, that its antiproliferative effect is mediated by alterations in cholesterol metabolism. Angiopeptin and other peptide analogues of somatostatin are potent inhibitors of growth hormone release and insulin-like growth factor-1 production. However, inhibition of smooth muscle cell proliferation in vivo is not a property common to all somatostatin analogues. This suggests that plasma growth hormone and growth hormone-dependent insulin-like growth factor-1 production are not physiologic stimuli for myointimal proliferation in vivo. Angiopeptin inhibits 3H-thymidine incorporation into rat carotid artery explants, suggesting a local effect on automne or paracrine mechanisms regulating cell growth. In view of its potent inhibitory effect on smooth muscle cell replication, angiopeptin may have clinical utility in preventing restenosis after percutaneous transluminal coronary angioplasty and in preventing accelerated coronary atherosclerosis after cardiac transplantation.
Laser balloon angioplasty: Potential for reduction of the thrombogenicity of the injured arterial wall and for local application of bioprotective materials
(1991) Spears JR; Kundu SK; McMath LP
Mitigation of adverse biologic reactivity after balloon angioplasty is necessary before the incidence of restenosis can be appreciably reduced. A brief review of experimental evidence supports the hypothesis that the thrombogenicity of the injured arterial wall can be reduced by a suitable level of thermal denaturation or cross-linking of thrombogenic proteins. In addition, the concept of local pharmacologic therapy, which can be provided with laser balloon angioplasty at the site of arterial injury, is introduced. Preliminary in vitro and in vivo data suggest that guide catheter-injected albumin-heparin conjugates fabricated as waterinsoluble microspheres remain adherent to the injured luminal surface and deeper arterial layers after physical trapping by the inflated balloon and subsequent laser/thermal exposure. The combination of initially adequate luminal morphology, reduction of the thrombogenicity of the injured arterial wall and application of local pharmacologic therapy with laser balloon angioplasty may eventually prove helpful in reducing the incidence of restenosis.
Fish oils in the prevention of atherosclerosis
(1992) Israel DH; Gorlin R
The hypothesis that oils derived from the flesh of fish and marine mammals inhibit the atherosclerotic process is critically reviewed. Populations consuming a diet rich in fish have low rates of coronary heart disease. Dietary fish oil is associated with changes in serum lipids, prostaglandin and leukotriene metabolism, enhanced endothelial function and effects on growth factors released from platelets, leukocytes and endothelial cells. Dietary fish oil supplementation has been associated with inhibition of atherosclerosis experimentally induced by dietary hyperlinidemia and balloon injury. Results of studies of the use of fish oil to inhibit postangioplasty restenosis in human subjects have bees inconclusive.
The rt-PA versus streptokinase controversy—III
(1992) Sherry S; Marder VJ
Recursively indefinite databases
(1993) van der Meyden R
We define recursively indefinite databases, a new type of logical database in which indefinite information arises from partial knowledge of the fixpoint of a Datalog program. Although, in general, query answering is undecidable, we show that queries containing only basic predicates and monadic defined predicates are decidable. The main contribution of the paper is an analysis of the complexity of query answering for this class of queries. We demonstrate a class of databases which generalizes disjunctive databases, but without increasing data complexity. We also establish connections with the theory of hypergraph edge replacement graph grammars.
Intracoronary irradiation markedly reduces restenosis after balloon angioplasty in a porcine model
(1994) Wiedermann JG; Marboe C; Amols H; Schwartz A; Weinberger J
Objectives. This study examined the effects of intracoronary Irradiation on neointimal proliferation after overstretch balloon angioplasty in a normolipemic swine model of restenosis. Background. Restenosis after percutaneous transluminal coronary angioplasty represents, in part, a proliferative response of vascular smooth muscle at the site of injury. We have previously shown that ionizing radiation, delivered by means of an intracoronary source, causes focal medial fibrosis. We therefore hypothesized that ntracoronary irradiation delivered at the time of balloon angtoplasty might impair the restenosis process. Methods. Nineteen juvenile swine underwent coronary angiography; a segment of the coronary artery was chosen as a target for balloon injury. In 10 swine, a ribbon of iridiun-192 was positioned at the target segment, and 2,000 cGy was delivered at the vessel wall. Subsequently, overdilation balloon angioplasty was perfromed at the irradiated segment. In nine control swine, overdilation balloon angioplasty was performed without previous irradiation. Eighteen animals survived and were killed at 30 days. Histopathologic analysis was performed by a pathologist in blinded manner. The area of maximal lumen compromise within the target segment was analyzed by computer-assisted planimetry. Results. In the control group, mean (± SD) neointimal area was 0.84 ± 0.60 mm2compared with that in the irradiated group, 0.24 ± 0.13 mm2(p = 0.01). In the control group, mean percent area stenosis was 47.6 ± 20.7%, whereas that in the irradiated group was 17.6 ± 10.5% (p = 0.001). This represents a 71.4% reduction in neointimal area and a 63.0% reduction in percent area stenosis in the irradiated group. Adjacent coronary segments and surrounding myocardium were unaffected. Conclusions. Intracoronary irradiation (2,000 cGy) delivered to a target porcine coronary segment before balloon overdilation markedly reduces neointima formation at 30 days and thus significantly impairs the restenosis process.
Grateful Thanks to Kerstin Thurow and Hilmar Weinmann for Eight Years of “Literature Highlights”
(2010) Ho D
Preliminary Studies of the Chemical Composition and Sensory Properties of Sweet Potato Starch-Wheat Flour Blend Noodles
(2013) Ibitoye WO; Afolabi MO; Otegbayo BO; Akintola AC
ABSTRACT Preliminary studies of chemical composition and sensory properties of instant noodles from blends of wheat flour and sweet potato starch were carried out. Sweet potato starch was used to replace wheat flour at 30, 40, 50, 60 and 70%. Proximate, vitamin A, mineral analysis and sensory evaluation were carried out by standard methods. Results showed that the formulated noodles had higher carbohydrate (63.34 – 70.53%), moisture (4.34 – 4.97%) and vitamin A (11.62 – 35.00mg/100g) but lower protein (3.36 – 7.89%), fat (16.91 – 25.09%), calcium (0.73 – 0.89%), phosphorus (0.24 – 0.32%), iron (0.10 – 0.27%) and ash content (1.17 – 3.17%) than the commercial noodles from wheat flour. The noodles containing 30% sweet potato starch showed no significant difference (p>0.05) from commercial noodles (100% wheat flour) in terms of colour, crunchiness, taste and general acceptability, with improved nutrient composition. It is concluded that production and consumption of wheat flour/potato starch blend noodles should be encouraged to increase the calorie and vitamin A intake in the diet, especially for children who are the major consumers of noodles; apart from helping to promote and improve the utilization of sweet potato tubers.
Effect of Storage on the Pasting Characteristics of Yam Tubers
(2014) Otegbayo BO
ABSTRACT Yam is a popular root and tuber crop which is important as a dietary staple and potential export crop. Storage of yam tubers is an age long practice in yam growing communities of West Africa, while pasting characteristic is an important indicator of potential utilization of yam tubers. The study was carried out to investigate effect of storage of the tubers on their pasting characteristics. Six varieties each of D. alata and D. rotundata were used for the study. At harvest, the tubers were divided into two groups. The first group was stored in a conventional open-air yam barn for four months, while tubers in the second group were not stored. Pasting characteristics of both fresh and stored tubers were determined by Rapid Visco Analyser (RVA). The result showed that the effect of storage on the yam tubers were species dependent. In D. alata there was an increase in peak viscosity (231.36 to 257.56 RVU), breakdown (71.68 to 122.47 RVU), setback (42.58 to 65.99 RVU), while there was a decrease in most of the parameters except break-down and setback viscosities in D. rotundata. Generally, a decrease in peak viscosity, holding strength, final viscosity and peak time of the yam tubers during storage was observed, while the breakdown and setback viscosities of the tubers increased significantly (p<0.05) on storage. The industrial implication of this is that starches of stored tubers may have high retrogradation tendencies but more resistance to shear-thinning and have more paste stability during processing.
Bromate and trace metal levels in bread loaves from outlets within Ile-Ife Metropolis, Southwestern Nigeria
(2014) Oyekunle JA; Adekunle AS; Ogunfowokan AO; Olutona GO; Omolere OB
Bread loaves randomly sampled from nine outlets and bakeries within Ile-Ife were analysed to determine their safety levels for human consumption with respect to bromate and trace metal contents. Bromate determination was carried out via spectrophotometric method while trace metals in the digested bread samples were profiled using Flame Atomic Absorption Spectrophotometer. Bromate levels in the analyzed bread samples ranged from 2.051 ± 0.011 μg/g to 66.224 ± 0.014 μg/g while the trace metal levels were of the order: 0.03–0.10 μg/g Co = 0.03–0.10 μg/g Pb < 0.23–0.46 μg/g Cu < 2.23–6.63 μg/g Zn < 25.83–75.53 μg/g Mn. This study revealed that many bread bakers around Ile-Ife had not fully complied with the bromate-free rule stipulated by NAFDAC contrary to the “bromate free” inscribed on the labels of the bread. The bread samples contained both essential and toxic trace metals to levels that could threaten the health of consumers over prolonged regular consumption.
Towards the development of shelf stable ‘iru’ (Parkia biglobosa) condiment bouillon cubes using corn, cassava and potato starch extracts as binders
(2015) Ajayi OA; Akinrinde IM; Akinwunmi OO
African locust bean (Parkia biglobosa), fermented into “iru” or “dadawa” is a nutritious condiment featured frequently in the diet of people of Nigeria and other West African countries. Many consumers benefit from the nutrients, and enjoy the aroma of fermented locust bean seed in their foods. However, some dislike seeing the locust beans and would pick them out of their meals depriving themselves of the nutrients. The availability of iru as fermented, ground and shelf stable bouillon cube may increase the acceptability of this condiment. The objective was to develop a shelf stable iru bouillon with starches as binders. Fermented, dried and ground locust bean with binders were prepared in the ratio of 40:10 and 30:20 locust bean:binder and cubed. Microbial and proximate analyses of the cubes were carried out. Bacillus spp., Lactobacillus spp., and Staphylococcus spp. were isolated following bouillon cube production. Cassava starch bouillons had the highest moisture content (24.5% and 29.3%). Bouillons with corn starch had the highest amount of fat (22.0%), followed by cassava starch (19.6%), while bouillon cubes with potato binder had the highest crude protein content (33.9%). Iru without binders had the lowest moisture (11.5%) and ash (1.7%), the highest crude fat (30.0%) and the highest crude protein (46.3%) contents. Only Bacillus subtilis was isolated from all the samples after 9 months of storage, indicating that shelf stable iru bouillon cubes is possible, without chemical preservatives. Conclusively, iru bouillon cubes with binders improved the shelf life from few days to over nine months without compromising the safety of the product.
Distribution of three non-essential trace metals (Cadmium, Mercury and Lead) in the organs of fish from Aiba Reservoir, Iwo, Nigeria
(2015) Atobatele OE; Olutona GO
The distribution of non-essential trace elements in some vital organs of 11 fish species from Aiba Reservoir, Iwo, Nigeria was assessed between November 2010 and June 2011. The fish species belong to seven families; family Mormyridae, family Cyprinidae, family Hepsetidae and family Channidae each with one species; family Bagridae and family Clariidae each with two species; and family Cichlidae with three species. All families, except Clariidae and Channidae, are common in the daily catch from the reservoir. Atomic absorption spectrophotometry was used to determine the levels of cadmium, mercury and lead in fish organs. The concentration of toxic trace metals in fish ranged from 0.001 to 0.100ppm (Cd), 0.000–0.067ppm (Hg) and 0.001–0.125ppm (Pb) dry weight. This study shows similarity (p>0.05) in the distribution of Cd, Hg and Pb among fish species; and a non-uniform distribution of toxic trace metals within fish organs with Kidney>Liver>Gill≥Intestine≥Muscle. Canonical variate analysis shows clear discrimination of Clarias macromystax and Channa obscura for gill trace metal levels of Cd, Hg and Pb while Labeo senegalensis and Oreochromis niloticus were discriminated for liver trace metal values of Cd and Pb only when compared to other fish species studied. The discrimination of some fish species based on trace metals in the gills and liver suggests different regulatory strategies for trace metal accumulation. Variation due to comparison among different fish species from the same water body suggests that accumulation may be species dependent. Differential accumulation of toxic trace metals in fish organs makes them good bioindicators of freshwater contamination.
Editorial Board
(2015)
Editorial Board
(2015)
Editorial Board
(2015)
Evaluating the potential of a Nigerian soil as an adsorbent for tartrazine dye: Isotherm, kinetic and thermodynamic studies
(2016) Dawodu MO; Akpomie KG
The release of toxic tartrazine dye from industrial effluent into the environment is of public health concern. This study therefore aimed at the removal of tartrazine from solution using Nigerian soil as a low cost potential sorbent. The sorbent was characterized by the Fourier transform infrared spectrophotometer and Scanning electron microscope. Batch sorption methodology was used to investigate the effect of pH, adsorbent dose, dye concentration, contact time and temperature. The sorbent recorded a Brunauer, Emmett and Teller surface area of 9.8m2/g and pH point of zero charge of 5.8. Optimum sorption was achieved at pH 2.0, contact time of 120min, adsorbent dose of 0.05g and tartrazine concentration of 50mg/L. Equilibrium isotherms were analyzed by the Langmuir, Freundlich, Scatchard and Flory-Huggins isotherm models. The pseudo-first-order, pseudo-second-order, Elovich and Bangham models were used for kinetic analysis. Thermodynamics revealed a spontaneous, feasible and endothermic sorption process. The soil was found to be suitable as a low cost sorbent for tartrazine from contaminated solution.
Hepato- and neuro-protective effects of watermelon juice on acute ethanol-induced oxidative stress in rats
(2016) Oyenihi OR; Afolabi BA; Oyenihi AB; Ogunmokun OJ; Oguntibeju OO
Chronic and acute alcohol exposure has been extensively reported to cause oxidative stress in hepatic and extra-hepatic tissues. Watermelon (Citrullus lanatus) is known to possess various beneficial properties including; antioxidant, anti-inflammatory, analgesic, anti-diabetic, anti-ulcerogenic effects. However, there is a lack of pertinent information on its importance in acute alcohol-induced hepato- and neuro-toxicity. The present study evaluated the potential protective effects of watermelon juice on ethanol-induced oxidative stress in the liver and brain of male Wistar rats. Rats were pre-treated with the watermelon juice at a dose of 4ml/kg body weight for a period of fifteen days prior to a single dose of ethanol (50%; 12ml/kg body weight). Ethanol treatment reduced body weight gain and significantly altered antioxidant status in the liver and brain. This is evidenced by the significant elevation of malondialdehyde (MDA) concentration; depletion in reduced glutathione (GSH) levels and an increased catalase (CAT) activity in the brain and liver. There was no significant difference in the activity of glutathione peroxidase (GPX) in the liver and brain. Oral administration of watermelon juice for fifteen (15) days prior to ethanol intoxication, significantly reduced the concentration of MDA in the liver and brain of rats. In addition, water melon pre-treatment increased the concentration of GSH and normalized catalase activity in both tissues in comparison to the ethanol control group. Phytochemical analysis revealed the presence of phenol, alkaloids, saponins, tannins and steroids in watermelon juice. Our findings indicate that watermelon juice demonstrate anti-oxidative effects in ethanol-induced oxidation in the liver and brain of rats; which could be associated with the plethora of antioxidant phyto-constituents present there-in.
Editorial Board
(2016)

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