Protective role of Telfairia occidentalis in irradiation-induced oxidative stress in rat brain

This study aimed at evaluating the protective role of Telfairia occidentalis extract (TOE) irradiationinduced oxidative stress in rat brain. Aqueous TOE was administered orally to adult rats for 30 days at doses of 400 mg/kg body weight, 800 mg/kg body weight and 1600 mg/kg body weight, and a corresponding group of rats were treated with 50 mg/kg body weight vitamin E (VE), a standard antioxidant before irradiation at a dose of 2 Gy of gamma rays. The control rats received distilled water only. The rats were observed and sacrificed at 24 hours, 15 and 30 days post-irradiation. The results demonstrated a significant increase in levels of malondialdehyde (MDA), an end product of lipid peroxidation (LPO) and hydrogen peroxide (H2O2) generation with a concomitant decrease in the activities of  superoxide dismutase (SOD), glutathione peroxidase (GSH-Px),  glutathione-S-transferase (GST), a phase two xenobiotic metabolizing enzyme, and a corresponding decrease in the level of reduced glutathione (GSH) after twenty-four hours, 15 and 30 days post-irradiation compared with the control. Treatments with TOE and VE significantly reversed  oxidative stress of irradiated rats when compared with the control rats. In conclusion, supplementation with TOE could reduce radiationinduced biochemical disorders in brain tissues.Keywords: Gamma radiation, oxidative stress, brain, rats and Telfairia occidentalis

Assessment of Post Fire Structural Strengths of Normal Strength Concrete Subjected to Cyclic Thermal Loadings

Concrete is a composite construction material consisting basically of a binder, aggregates, water and with or without admixture to modify either or both its physical and chemical properties. The rate at which concrete structures especially buildings are gutted by fire hazards is on the increase and this has adverse effect on the strength, hence, the need to  assess the post fire structural strengths of Normal Strength Concrete(NSC). NSC of grade 50 was produced and cast into specimens of sizes 150mm cubes and 100mm x 100mm x 500mm reinforced concrete beams. The concrete cubes and beams were subjected to elevated cyclic thermal loadings after 7, 14 and 28 days of curing, while the rate of heating was maintained at 1oC/min until the target temperature of (100, 130, 160, 200 and 250)o C where attained and this was maintained for one hour and then allowed to cool at 1oC/min to room temperature of 32oC.         Unstressed Residual Uniaxial Compressive Test (URUCT and Flexural Strength Test (FST) were conducted on the cubes and reinforced concrete beams, respectively. Direct Tensile Strength Test (DTST) was performed on the high yield (460N/mm2) steel reinforcement. The result showed that the residual compressive strengths of concrete cubes decreases with increase thermal loadings. The expected strengths of 0.69 and 0.97 of the 28 days strength for 7 and 14 days respectively were met. The flexural strengths decrease with increase in thermal loadings. The flexural strength of the concrete beams at 28 days of 15.25N/mm2 at thermal loading of 32oC was reduced to 8.16/mm2 at thermal loading of 160oC; while the strength at 14 days of 12.19 N/mm2 at thermal loading of 32oC was reduced to 7.62N/mm2 at thermal loading of 160oC and finally, the strength at 7 days of 10.13N/mm2 at thermal loading of 32oC was reduced to 5.82N/mm2 at thermal loading of 160oC. All the results met the specification for high yield steel of 12% elongation at fracture. It was concluded that within the thermal loading range adopted, the tensile strength of the reinforcement was not impaired beyond the limit specified by the code. Keyword: Normal Strength Concrete, Thermal loadings, Unstressed Residual  Strength Test, Fire hazard

Natural Nanoparticles: A Particular Matter Inspired by Nature

During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as “synthetic” and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, “nano” does not always equate with “artificial”. Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent—and sometimes unexpected—advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions—pardon—suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical use

Milling the Mistletoe: Nanotechnological Conversion of African Mistletoe (Loranthus micranthus) Intoantimicrobial Materials

Nanosizing represents a straight forward technique to unlock the biological activity of complex plant materials. The aim of this study was to develop herbal nanoparticles with medicinal value from dried leaves and stems of Loranthus micranthus with the aid of ball-milling, high speed stirring, and high-pressure homogenization techniques. The milled nanoparticles were characterized using laser diffraction analysis, photon correlation spectroscopy analysis, and light microscopy. The average size of leaf nanoparticles was around 245 nm and that of stem nanoparticles was around 180 nm. The nanoparticles were tested for their antimicrobial and nematicidal properties against a Gram-negative bacterium Escherichia coli, a Gram-positive bacterium Staphylococcus carnosus, fungi Candida albicans and Saccharomyces cerevisiae, and a nematode Steinernemafeltiae. The results show significant activities for both leaf and (particularly) stem nanoparticles of Loranthus micranthus on all organisms tested, even at a particle concentration as low as 0.01% (w/w). The results observed indicate that nanoparticles (especially of the stem) of Loranthus micranthus could serve as novel antimicrobial agents with wide-ranging biomedical applications

Alteration in sperm characteristics, endocrine balance and redox status in rats rendered diabetic by streptozotocin treatment: attenuating role of Loranthus micranthus

Objectives: Loranthus micranthus is widely used in Nigerian folklore treatment of male infertility and diabetes complications. We investigated this claim in rats rendered diabetic by streptozotocin (STZ). Methods: Induction of diabetes mellitus in adult male Wistar rats was by intraperitoneal injection of STZ (60 mg/kg). The diabetic rats were thereafter treated orally once/day with 5 mg/kg Gilbenclamide or L. micranthus (100 mg/kg or 200 mg/kg) and monitored for 14 days. Clinical observations, hormonal profile, oxidative stress parameters, glucose metabolism enzymes, histopathological examination, apoptotic marker immunoreactivity and western blotting in testes and sperm parameters were evaluated to examine effects of L. micranthus on STZ-diabetic rats. Results: L. micranthus treatment significantly reduced the blood glucose level (45.9% and 84.7% on the 7th and 14th post-treatment days, respectively); increased antioxidant status, improved microarchitecture of testes, reduced lipid peroxidation and increased BCl-2 protein expression in diabetic rats relative to control. Furthermore, treatment with L. micranthus increased steroidogenic enzymes activities, levels of steroid hormones and improved sperm quality, relative to control. Conclusion: The anti-diabetic and aphrodisiac properties exhibited by L. micranthus could be contingent on its ability to restore a balance to the compromised redox status that characterizes male reproductive dysfunction in diabetes

Natural Nanoparticles: A Particular Matter Inspired by Nature

During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as “synthetic” and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, “nano” does not always equate with “artificial”. Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent—and sometimes unexpected—advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions—pardon—suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical uses