575 research outputs found
Multiwall carbon nanotube reinforced HA/HDPE biocomposite for bone reconstruction
The healing of bone fractures naturally occurs without surgical intervention. Some damage and fractures in bone tissue are complex and leave remnant deformation, and this requires the use of bone replacement material. Hydroxyapatite (HA) is the main element of the bone mineral form and consider as a bioactive material which supports bone growth. Nevertheless, the HA has poor mechanical properties, such as low tensile strength. Thus the applications in bone replacement have been limited, especially in high load-bearing applications. A Carbone nanotube has newly obtained considerable concern because of their mechanical properties, potentially enhancing the bone implant's clinical efficiency. This study attempted to explain the effect of adding Multi-walled carbon nanotubes MWCNT Nanoparticles to the HDPE/HA bio-composites. Two groups of the composites samples were produced 20HA/80 HDPE and 40 HA/ 60 HDPE with adding (0.6, 1, 1.4, 2) % weights of (MWCNT) to each group. The composites were fabricated using a hot pressing technique with various pressing pressures (29, 57, 86, and 114 Mpa) at a compounding temperature of 150 C° and a holding time of 15 minutes. To evaluate samples' characteristics and performance, X-ray powder diffraction (XRD), surface topography by Field Emission Scanning Electron Microscopy (FE-SEM), tensile strength and, microhardness test were investigated. The results showed that the hybrid bio-composites demonstrated excellent structural integrity, homogeneous with the fibrous structure, and improved mechanical properties. When increasing in MWNT additions and increasing hot-press pressure, enhancing the composites' fracture strength and microhardness is beneficial. The excellent properties of hybrids bio-composite (HA/HDPE/MWCNT) samples for homogeneous fibrous structure and high mechanical properties could be applied in bone tissue engineering for bone reconstruction
The chemopreventive effect of Ginkgo biloba and Silybum marianum extracts on hepatocarcinogenesis in rats
<p>Abstract</p> <p>Background/objective</p> <p>This study was designed to evaluate the potential chemopreventive activities of <it>Ginkgo biloba </it>extract (EGb) and <it>Silybum marianum </it>extract (silymarin) against hepatocarcinogenesis induced by N-nitrosodiethylamine (NDEA) in rats.</p> <p>Methods</p> <p>Rats were divided into 6 groups. Group 1 served as normal control rats. Group 2 animals were intragastrically administrated NDEA at a dose of 10 mg/kg five times a week for 12 weeks to induce hepatocellular carcinoma (HCC). Groups 3 and 4 animals were pretreated with silymarin and EGb respectively. Groups 5 and 6 animals were posttreated with silymarin and EGb respectively. The investigated parameters in serum are alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT) and vascular endothelial growth factor (VEGF). The investigated parameters in liver tissue are malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and comet assay parameters.</p> <p>Results</p> <p>In NDEA group, MDA level was elevated with subsequent decrease in GSH level and SOD, GPx and GR activities. In addition, NDEA group revealed a significant increase in serum ALT, AST and GGT activities and VEGF level. Furthermore, NDEA administrated animals showed a marked increase in comet assay parameters. These biochemical alterations induced by NDEA were confirmed by the histopathological examination of rat livers intoxicated with NDEA that showed an obvious cellular damage and well differentiated HCC.</p> <p>In contrast, silymarin+NDEA treated groups (3&5) and EGb+NDEA treated groups (4&6) showed a significant decrease in MDA level and a significant increase in GSH content and SOD, GPx and GR activities compared to NDEA group. Silymarin and EGb also beneficially down-regulated the increase in serum ALT, AST, GGT activities and VEGF level induced by NDEA. In addition, silymarin and EGb significantly decreased comet assay parameters. Histopathological examination of rat livers treated with either silymarin or EGb exhibited an improvement in the liver architecture compared to NDEA group.</p> <p>Conclusions</p> <p>The obtained findings suggested that silymarin and EGb may have beneficial chemopreventive roles against hepatocarcinogenesis through their antioxidant, antiangiogenic and antigenotoxic activities.</p
Anti-inflammatory and hepatoprotective potentials of the aerial parts of Silene villosa Caryophyllaceae methanol extract in rats
Purpose: To explore the anti-inflammatory and hepatoprotective potentials of Silene villosa Caryophyllaceae methanol extract in rats.Methods: Toxicity of S. villosa extract was evaluated in rats. Inflammation was induced in rats by injection of 0.1 mL carrageenan (1 %) in the left hind paws. Carbon tetrachloride (CCl4) was used to induce liver damage. Five groups of rat were used. The 1st (normal control) and 2nd (hepatotoxic) groups received the vehicle. The 3rd, 4th, and 5th groups received silymarin, 250 and 500 mg/kg of S. villosa extract, respectively, for 7 days. Liver injury was induced on the 7th day by intraperitoneal administration of 1 mL/kg of CCl4 to rats in groups 2 - 5.Results: The results showed that S. villosa is safe. It significantly reduced carrageenan-induced edema compared to normal (p < 0.01) and standard (p < 0.01) groups. The extract protected (p < 0.01) rats against the deleterious effect of CCl4. It decreased (p < 0.01) the elevated serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (γ-GT) and alkaline phosphatase (ALP) as well as elevated serum levels of bilirubin (BRN), compared to CCl4 control rats. Reduced activities of the antioxidant enzymes were significantly increased (p < 0.01) in rat liver, compared with CCl4 control group. The results were confirmed by histological findings in rat liver as the extract reduced necrosis and hydropic degeneration of hepatic tissue compared to CCl4 control group.Conclusion: The results suggest that S. villosa possesses anti-inflammatory and hepatoprotective activities in rats, and therefore, has therapeutic potentials in humans.Keywords: S. villosa, anti-inflammatory, carrageenan, CCl4, antioxidant, hepatotoxicity
Delineating groundwater and subsurface structures by using 2D resistivity, gravity and 3D magnetic data interpretation around Cairo–Belbies Desert road, Egypt
AbstractGeophysical tools such as magnetic, gravity and electric resistivity have been used to delineate subsurface structures, groundwater aquifer around Cairo–Belbies Desert road. A dipole–dipole section was measured at the central part of the study area with 2100m length and electrode spacing 50m for greater penetration depth. The results of the inverse resistivity data indicate that the study area includes two groundwater aquifers at different depths. The shallow aquifer water is near the surface and the deep aquifer lies at depth of about 115m and exhibits low resistivity values ranging from 20 to 100ohmm.One hundred and fifty-two gravity stations were measured using Autograv gravimeter (CG3), different gravity corrections (drift, elevation and latitude corrections) were applied. The corrected data represented by Bouguer anomaly map were filtered into regional and residual gravity anomaly maps. The residual gravity map indicates that the area is dissected by many faults with NW-SE, N-S, E-W and NE-SW trends.One hundred and fifty-three ground magnetic measurements are collected using two Proton magnetometers (Envimag). The corrected magnetic data are represented by total magnetic intensity map that was reduced to the magnetic pole. 3D magnetic modeling was applied to detect the depth of basaltic sheet and basement complex. The results indicated that the elevation of upper surface of basalt is ranging from 148 to −153m and the elevation of lower surface of basalt is ranging from 148 to 269m
Bisphenol A-associated epigenomic changes in prepubescent girls: a cross-sectional study in Gharbiah, Egypt
Abstract
Background
There is now compelling evidence that epigenetic modifications link adult disease susceptibility to environmental exposures during specific life stages, including pre-pubertal development. Animal studies indicate that bisphenol A (BPA), the monomer used in epoxy resins and polycarbonate plastics, may impact health through epigenetic mechanisms, and epidemiological data associate BPA levels with metabolic disorders, behavior changes, and reproductive effects. Thus, we conducted an environmental epidemiology study of BPA exposure and CpG methylation in pre-adolescent girls from Gharbiah, Egypt hypothesizing that methylation profiles exhibit exposure-dependent trends.
Methods
Urinary concentrations of total (free plus conjugated) species of BPA in spot samples were quantified for 60 girls aged 10 to 13. Genome-wide CpG methylation was concurrently measured in bisulfite-converted saliva DNA using the Infinium HumanMethylation27 BeadChip (N = 46). CpG sites from four candidate genes were validated via quantitative bisulfite pyrosequencing.
Results
CpG methylation varied widely among girls, and higher urinary BPA concentrations were generally associated with less genomic methylation. Based on pathway analyses, genes exhibiting reduced methylation with increasing urinary BPA were involved in immune function, transport activity, metabolism, and caspase activity. In particular, hypomethylation of CpG targets on chromosome X was associated with higher urinary BPA. Using the Comparative Toxicogenomics Database, we identified a number of candidate genes in our sample that previously have been associated with BPA-related expression change.
Conclusions
These data indicate that BPA may affect human health through specific epigenomic modification of genes in relevant pathways. Thus, epigenetic epidemiology holds promise for the identification of biomarkers from previous exposures and the development of epigenetic-based diagnostic strategies.http://deepblue.lib.umich.edu/bitstream/2027.42/112909/1/12940_2013_Article_648.pd
Exercise capacity and muscle fatiguability alterations following a progressive maximal exercise of lower extremities in children with cystic fibrosis
Background: Impairment of peripheral skeletal muscle function is a
common phenomenon in patients with cystic fibrosis (CF) in addition to
great clinical connotations, such as lack of exercise tolerance and
decrease of health-related quality of life. There is very limited data
on the effects of maximal exercise on muscle fatiguability and exercise
capacity in children with cystic fibrosis. Objectives: The aim of this
study was to evaluate the effect of progressive maximal exercise
training of the lower extremities on exercise capacity and muscle
fatiguability in children with cystic fibrosis. Study design: Between
June and September 2017, eighteen children aged 8-12 years were
recruited in this study. This study had two groups of children; the CF
group consisted of nine children (6 males and 3 females) with cystic
fibrosis and the control group consisted of nine healthy age matched
children (6 males and 3 females). The children underwent a progressive
maximal cardiopulmonary exercise cycling test (CPET), muscle fatigue
test, and magnetic resonance imaging (MRI) to measure a muscle
cross-section area (CSA). Also, pulmonary functions were assessed.
Results: The findings of this study showed that the CF children had
less pulmonary functions, had a less exercise capacity, and had a
higher breathing reserve index and oxygen desaturation when compared
with healthy children (p<0.05). On the other hand, there was a
non-significant difference in muscle fatiguability, muscle
cross-section area, and maximal voluntary contraction between the CF
and healthy children (p>0.05). Conclusion: This study indicates that
progressive maximal exercise doesn\u2019t affect muscle fatiguability,
muscle cross-section area, and maximal voluntary contraction in CF
children with moderate respiratory diseases but includes lower exercise
capacity. CF children and healthy age matched children have similar
responses to maximal exercise in muscle fatiguability, muscle
cross-section area, and maximal voluntary contractions but lower
exercise capacity in the CF group
Corrigendum to “Chemical constituents and protective effect of Ficus ingens (Miq.) Miq. on carbon tetrachloride-induced acute liver damage in male Wistar albino rats” [Journal of Saudi Chemical Society 17/1 (2013) 125–133]
Fabrication and Characterization of Effective Biochar Biosorbent Derived from Agricultural Waste to Remove Cationic Dyes from Wastewater
The main aim of this work is to treat sugarcane bagasse agricultural waste and prepare an efficient, promising, and eco-friendly adsorbent material. Biochar is an example of such a material, and it is an extremely versatile and eco-friendly biosorbent to treat wastewater. Crystal violet (CV)-dye and methylene blue (MB)-dye species are examples of serious organic pollutants. Herein, biochar was prepared firstly from sugarcane bagasse (SCB), and then a biochar biosorbent was synthesized through pyrolysis and surface activation with NaOH. SEM, TEM, FTIR, Raman, surface area, XRD, and EDX were used to characterize the investigated materials. The reuse of such waste materials is considered eco-friendly in nature. After that, the adsorption of MB and CV-species from synthetically prepared wastewater using treated biochar was investigated under various conditions. To demonstrate the study’s effectiveness, it was attempted to achieve optimum effectiveness at an optimum level by working with time, adsorbent dose, dye concentration, NaCl, pH, and temperature. The number of adsorbed dyes reduced as the dye concentrations increased and marginally decreased with NaCl but increased with the adsorbent dosage, pH, and temperature of the solution increased. Furthermore, it climbed for around 15 min before reaching equilibrium, indicating that all pores were almost full. Under the optimum condition, the removal perecentages of both MB and CV-dyes were ≥98%. The obtained equilibrium data was represented by Langmuir and Freundlich isotherm models. Additionally, the thermodynamic parameters were examined at various temperatures. The results illustrated that the Langmuir isotherm was utilized to explain the experimental adsorption processes with maximum adsorption capacities of MB and CV-dyes were 114.42 and 99.50 mgg, respectively. The kinetic data were estimated by pseudo-first and pseudo-second-order equations. The best correlation coefficients of the investigated adsorption processes were described by the pseudo-second-order kinetic model. Finally, the data obtained were compared with some works published during the last four years
INSULIN-MIMETIC ACTIVITY OF STEVIOSIDE ON DIABETIC RATS: BIOCHEMICAL, MOLECULAR AND HISTOPATHOLOGICAL STUDY
Background: Stevioside has been used as a medication for reducing glucose levels in diabetic patients. The exact mode of action is still unclear. Therefore, the current study outlines the molecular and biological roles of stevioside in treatment of diabetes.
Materials and Methods: induced diabetic male wistar rats treated with stivioside and metformin as therapy for diabetic rats. Biochemical, molecular and histopathological studies have been done to evaluate the therapeutic effect of stevioside on minimizing levels of glucose in diabetic rats.
Results: Stevioside administration normalized kidney and liver biomarkers, restored alterations in antioxidants activity and lipid profiles. Moreover, stevioside increased insulin and leptin secretion that are decreased in diabetic rats to the normal levels.For mRNA expression, stevioside up-regulated the expressions of PK and IRS-1 genes which are down-regulated in diabetic rats, and was very effective in down-regulation of CPT-1 mRNA expression. At the cellular levels; stevioside normalized the histopathological changes induced in pancreas.
Conclusion: Stevioside has insulin like effects and it is useful for diabetic patient’s therapy
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