سال:1397 | دوره: | شماره: |تعداد مقالات:8

Extensive research on the nutritional and medical application of selenium nanoparticles (SeNPs) was performed in past decades. Besides nutritional values, new characteristics such as antibacterial and anticancer properties depict a bright future for high Selenium (Se) consumption in the coming years. Se is essential for the proper functioning of most of the major body organ systems meanwhile it could be highly toxic and even cancerous. The current knowledge of Se interaction with major organ systems functionality such as the central nervous system isn’ t well studied and many physiological aspects aren’ t clear to the science community. Meanwhile, various results were published on increasing organ system functionality through administrated SeNPs. So with the rapid entrance of SeNPs in the medical and nutritional industry, it may cause unintended complications. The intent of this review is to investigate current knowledge of SeNPs interaction with major body organ systems functionality. Investigated pharmacokinetic parameters of SeNPs was also reviewed...

Objective(s): Since microbial contamination can reduce the shelf life of the foodstuff and there is a potential for the growth of some pathogen microorganisms, films containing antimicrobial agents were produced, which are also biodegradable. In this study, the effect of 1, 3 and 5% nano-zinc oxide on antimicrobial properties and permeability of poly lactic acid film was investigated. Material and methods: the sample was contaminated with standard strains of gram-negative (Escherichia coli – code of 1399 (ATCC 25992)) and bacteria grampositive (Staphylococcus aureus– code of 1431 (ATCC 25923)) provided. Diameters of inhibition zones were measured after 24 h incubation of plates at 37 ° C, by using Digital Caliper. Also, the permeability to water vapor according to ASTM E96 and oxygen standards according to ASTM D3985 standard was investigated from film surface. Results: The study of antimicrobial properties of films on Escherichia coli and Staphylococcus aureus showed that all three percent of “ ZnO” in this study had inhibitory effects and increased the percentage of nano-zinc oxide significantly (P <0. 05) increased the inhibitory effects. In this test, the diameter of the control film inhibition zone was zero, which indicates that pure poly lactic acid films do not have antimicrobial activity (P > 0. 05). In the study of Water Vapor Permeability (WVP), bio-composite films with 1% and 3% nano-zinc oxide showed a 19% water vapor Permeability enhancement compared to the pure poly-lactic acid. Moreover, adding 3% nano-zinc oxide had an impact on the reduction of permeability to oxygen. Conclusion: Poly lactic acid films containing nano-zinc oxide have a high potential for antimicrobial food packaging applications to enhance the safety of food products.

Objective(s): The objective of the current study was to prevent surgical site infection (SSI) by creating a new antibacterial silk suture. Methods: Cefixime trihydrate (CFX) was prepared as nanoparticles via mixing with polyvinyl alcohol (PVA) hydrogel by covalent cross-linkage. The mixture was stirred vigorously to obtain a homogenous gel. Under this condition the polymer chains separate CFX as nanoparticles and trap them (CFX@PVA). The enrichment of silk suture was performed by immersing it in the CFX@PVA solution. The trapped CFX nanoparticles in PVA hydrogel on the surface of sutures were confirmed by SEM. The effect of CFX@PVA silk sutures on tensile strength was analyzed, using a Santam machine controller. The antibacterial activity of the reinforced silk suture was tested on E. coli (ATCC25922) and S. aureus (ATCC25924). Results: All antibacterial studies clearly showed that the use of novel CFX@PVA silk sutures could represent clinical advantages, in terms of prevention of resistant bacteria, such as Staphylococcus aureus (S. aureus), the same as the sensitive bacteria, for 15 days. The maximum elongation of composite before rupture, modulus and extension, showed statistically significant difference between reinforced silk sutures and untreated silk suture. No statistically significant difference was found between the Failure load, Stress, Bending and Energy. Conclusions: Our data indicate that CFX@ Silk sutures are capable of reducing the risk of SSIs, and has a good mechanical strength to keep the wound sides closed, during early healing recovery.

Objective(s): Silver nanoparticles show anti-fungal properties, and is widely used in medicine. In this research, the impacts of silver nanoparticles on the hepatic functional tests and changes in liver tissues in adult male rats were investigated. Methods: In this experimental study, 28 adult male Wistar rats, each weighing approximately 180-220 g were divided into 4 groups of 7: the control group, and the experimental groups 1 and 2 received silver nanoparticles that were synthesized at 75 seconds interval with doses of 25 and 100 mg/kg intraperitoneally for 14 days, respectively. Experimental group 3 received silver nanoparticles that were synthesized at 300 seconds interval with a dose of 25 mg/kg intraperitoneally for 14 days. At the end of experiment period, blood samples were obtained from their hearts, and serum levels of hepatic enzymes (AST, ALT, ALP), albumen and total protein were measured. In addition, possible histological changes in liver was studied after hematoxylin-eosin staining. The results were statistically analyzed using ANOVA and Duncan test. Results: The findings reported that the mean serum levels of aspartate aminotransferase (AST), total Protein and albumin in the experimental groups 1 and 3 increased significantly relative to the control group. Similarly, the mean serum levels of alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in the experimental group 3 increased significantly relative to the control group (P < 0. 05). Also, necrosis of the liver tissue was observed in the recipients of silver nanoparticles. Conclusions: The use of silver nanoparticles can boost the serum levels of hepatic enzymes and Increase liver tissue necrosis as well.

Co-Cr and Co-Cr/nano-TiO2 coatings were electrodeposited from Cr(III) based baths. The effect of TiO2 nano-particles incorporation on the morphology, structure, crystallite size, and preferred orientation was studied. Corrosion behavior of the composite coating was also investigated by means of polarization and electrochemical impedance spectroscopy techniques in Hanks’ simulated body fluid, and the results were compared to the unreinforced Co-Cr film. SEM micrographs revealed that the TiO2 nano-particles have been distributed uniformly within the Co-Cr matrix. Co-deposition of these particles insignificantly changed the nodular morphology of the Co-Cr film. Both the coatings had hcp-Co structure with the highest relative texture coefficient (RTC) for the (100) peak. According to the corrosion results, corrosion potential of the Co-Cr/TiO2 was nobler than the Co-Cr film and its corrosion current density was about 0. 75 of that for the unreinforced alloy coating. The charge transfer resistance of the Co-Cr coating in Hanks’ solution was increased from 73. 6 to 127. 9 kΩ cm2 by incorporation of TiO2 nano-particles. However, the double layer capacitance of the Co-Cr film was about 3 times higher than the Co-Cr/TiO2 coating. . .

Objective(s): The use of new technologies, which can be realized as nanotechnology, is a novel approach in this sector. Covers made of silver nanoparticles effectively prevent and reduce invasion of microorganisms, compared with other conventional covers. This study was conducted to determine the effects of nanosilver covers in comparison with other conventional covers. Materials and methods: In order to measure the effect of antibacterial nano-covers, in comparison with other commonly used covers in packing food products, the direct contact of covers with food (in this study, mince mixture of sheep - calf) was used as control. Furthermore, the sample was contaminated with standard strains of gram-negative and gram-positive bacteria in specified time periods (zero, 24, 48 and 72 hours) was performed. Findings: Despite the large number of Staphylococcus aureus colonies in meat tested as normal flora, except for one case, no other positive Staphylococcus aureus coagulase bacteria were either found or reported by confirmatory tests; however, the absence of even a colony of positive staphylococci coagulase, despite the manual infection of 2 sections from 7 sections, raised the possibility of the domination of Escherichia coli bacteria and prevention of the growth of Staphylococcus aureus bacteria in the broth. Conclusion: Nano-silver cover has been identified as the most efficient cover in reducing the microbial load and increasing the shelf life of mince.

Conclusions: The teratogenic effects of nanozeolits on chick embryo should be considered in the risk assessment of nanoparticles on human embryo and fetous.