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81.
The extracts prepared from various areal parts of the Adenium obesum (Forssk.) Roem. & Schult. (Family: Apocynaceae) including leaves, fruit and seeds ethanolic extracts and seed aqueous extract were evaluated against MCF-7 cells in order to investigate its potential of cytogenotoxicity and induction of apoptosis. The ethanolic seeds extract had comparatively higher cytotoxicity (IC50?~?337?µg/ml). Further, apoptosis and DNA damaging potential of seeds ethanolic extract was analyzed by applying multiple sub-lethal concentrations and durations. Flow cytometry results revealed that maximum percentage of early apoptosis (37%) and late apoptosis (35%) were observed after 12?h exposure in concentrations 200?µg/ml and 300?µg/ml, respectively. Similarly, the higher effect of extract in terms of DNA damage by alkaline comet assay was registered after 12?h treatment at concentrations 200 and 300?µg/mL. The calculated total damage score (TDS) for these concentrations were 614 and 617, respectively. The above findings indicate that A. obesum ethanolic seeds extracts has cytogenotoxic properties that could be further explored for the potential source of chemotherapeutic lead against cancer.  相似文献   
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Various viruses can infect honey bees, but deformed wing virus (DWV) is considered the most dangerous virus to them and has role in the sudden decline of bee colonies. This virus has different strains; however, there are no available studies to compare the characteristics of these strains utilizing bioinformatics. In this study, 27 strains of deformed wing virus were analyzed based on their sequences and their genetic relationships. Also, some primers were designed and tested to identify their ability to separate DWV strains. The percentages range from 28.99% to 29.63%, 22.28% to 22.78%, 15.73% to 16.28%, and 31.71% to 32.86% for nucleotides A, G, C, and T, respectively in all strains. The numbers of polymorphic sites as well as nucleotide diversity were highly similar in all strains. Statistical analyses generally showed the absence of high variations between sequences. Also, the phylogenetic tree classified strains into three groups. The network between strains of each group was established and discussed based on their geographical locations. Two groups contained strains from USA and Europe while one group contained strains from Asia. Rapid variations and mutations in the sequences of DWV were suggested. Notably, genetic studies on DWV are lacking in some geographical regions. The variations between strains detected in honey bees and other organisms were discussed. Four primers were designed and tested beside two reference primers. One of the designed primers showed the best results in binding with all DWV strains except one.  相似文献   
84.
At present, chicken business is occupying a major portion in the market and huge amount of bone wastes are dumped into the open places lead in environmental pollution. In this analysis, natural hydroxyapatite was extracted by thermal calcination process at different temperature ranges from 700 °C, 900 °C and 1100 °C and compared its spectral characteristics. The crystalline nature, functional groups and morphological characteristics of hydroxyapatite obtained from both bone samples were studied using XRD, FTIR and SEM analysis. The crystallite size, lattice parameters, specific surface area, volume and degree of crystallinity were measured using XRD data. The mean grain size of Black Sumatra and Fighting Cock bone hydroxyapatite was 62.67 nm and 31.34 nm respectively. The FTIR spectrum showed major peaks at 634.58 cm−1 and 470.63 cm−1, 1413.82 cm−1 and 1460 cm−1 indicates the presence of carbonate group and phosphate groups in both samples. The SEM micrograph confirmed the existence of maximum pores in matrix of fighting cock bone than Black Sumatra bone sample. Thus, the comparative analysis concluded that nano-sized hydroxyapetite obtained from bone wastes of fighting cock can be utilized as a low-cost biomaterial for the production of various implant coating materials and substitute for ceramics in bones and dentistry applications.  相似文献   
85.
Bisphenol-A (BPA), an organic compound with two phenol functional groups, is a widely used industrial plasticizer with known estrogenic properties. It is used in the manufacture of epoxy resins and polycarbonate plastics. This study was designed to evaluate and assess the possible toxicity arising from the oral administration of BPA to pregnant mice. Pregnant SWR/J mice (15 mice/group) were administrated oral doses of BPA (125, 250 and 500 mg/kg/day) over the course of five-day intervals during gestation (D1-5, D6-10 and D11-15), while control groups received only corn oil. The results indicated that BPA was associated with a reduction in the body weight of the pregnant mice from around 2–3 days after administration until the end of gestation. The greatest effects were evident when the BPA was given during the later stages of pregnancy, and with higher doses. They also showed marked reduction in food intake and, to a lesser extent, in water intake. Furthermore, doses of BPA induced a reduction in implantation sites, lower foetal body weight and increased mortality rates. Abortion and foetal resorption rates were not affected by BPA administration, however. The above findings were concluded by discussing the possible mechanisms involved in producing these effects.  相似文献   
86.
With the increasing prevalence of cancer and the toxic side effects of synthetic drugs, natural products are being developed as promising therapeutic approaches. Gracillin is a naturally occurring triterpenoid steroidal saponin with several therapeutic activities. It is obtained as a major compound from different Dioscorea species. This review was designated to summarize the research progress on the anti-cancer activities of gracillin focusing on the underlying cellular and molecular mechanisms, as well as its pharmacokinetic features. The data were collected (up to date as of May 1, 2023) from various reliable and authentic literatures comprising PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. The findings demonstrated that gracillin displays promising anticancer effects through various molecular mechanisms, including anti-inflammatory effects, apoptotic cell death, induction of oxidative stress, cytotoxicity, induction of genotoxicity, cell cycle arrest, anti-proliferative effect, autophagy, inhibition of glycolysis, and blocking of cancer cell migration. Additionally, this review highlighted the pharmacokinetic features of gracillin, indicating its lower oral bioavailability. As a conclusion, it can be proposed that gracillin could serve as a hopeful chemotherapeutic agent. However, further extensive clinical research is recommended to establish its safety, efficacy, and therapeutic potential in cancer treatment.  相似文献   
87.
Selenium is an essential element with a narrow margin between beneficial and toxic effects. This study was aimed to determine the neurobehavioral changes resulted from the prenatal exposure of mice to high doses of sodium selenite during fetal and early postnatal development. Atomic absorption for monitoring the placental transfer of selenium to offspring was employed. The developmental observations as well as the behavioral tests, such as sensory motor reflexes, and learning and memory test in automatic reflex conditioner (shuttle box) (active avoidance responses) were applied. Adult mice was assigned into three groups: the first group was remained as a control group given phosphate buffered saline; the second and the third groups were orally administrated sodium selenite at doses of 1 mg/kg and 4 mg/kg of the diet, respectively started from the 7th day to the end of the gestation period. Appearance of body hair and opening of eyes of the pups from treated mothers were delayed in a dose-dependent manner. The body weight gain came significantly lower than those of the control especially at the higher dose. Selenite also inhibited the sensory motor reflexes in all elements of acts and postures in a dose dependent manner. The active avoidance training-test indicated that selenite exposure was associated with learning impairment. Acetylcholine recorded a significant decrease in almost all the period of this study. By using atomic absorption, we found a significant high concentration of selenium in the brain, liver and kidney until the 40th postnatal day, indicating active transfer of selenium from mothers to embryos.  相似文献   
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89.
Data have demonstrated that whey protein (WP) enhances the immune system. The aim of this study was to investigate and compare the effects of WP from three camel breeds on oxidative stress, blood lipid profile and the cytokine levels. Seventy five male mice were randomly split into five groups. The first served as a control group. The second, the third and the fourth groups were orally administrated the WP from Majaheim, Maghateer and Soffer camel breeds, respectively, at a dose of 100 mg/kg mouse body weight. The fifth group was supplemented with bovine serum albumin (BSA). Results showed similar electrophoretic patterns of the three whey proteins. WP was found to significantly inhibit the hydroperoxide and the Reactive Oxygen Species (ROS) in leukocytes, liver and skin as well as the blood cholesterol level in a time dependent manner. A significant enhancement of glutathione was revealed in WP groups. Furthermore, WP was found to significantly elevate the IL-2 with a significant time dependent enhance of IL-8. On contrast, a significant lowering effect of whey proteins on the pro-inflammatory cytokines, IL-1α, IL-1β, IL-6 and IL-10 was detected. Moreover, a mitogenic activity of WP was observed on the lymphocytes. Non-significant changes were observed in AST, ALT, creatinine and glucose level. These findings suggest that WP significantly improved the levels of the oxidative markers and the immune functions without any difference in the bioactivities of the three studied whey proteins.  相似文献   
90.
BioMetals - In this study, a novel, non-toxic, eco-friendly zinc oxide nanoparticles (ZnO-NPs) was used instead of the synthetic fungicides widely used to control the destructive phytopathogenic...  相似文献   
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