414 research outputs found
Thermoluminescence responses of photon- and electron-irradiated lithium potassium borate co-doped with Cu+Mg or Ti+Mg
New glasses Li2CO3–K2CO3–H3BO3 (LKB) co-doped with CuO and MgO, or with TiO2 and MgO, were synthesized by the chemical quenching technique. The thermoluminescence (TL) responses of LKB:Cu,Mg and LKB:Ti,Mg irradiated with 6 MV photons or 6 MeV electrons were compared in the dose range 0.5–4.0 Gy. The standard commercial dosimeter LiF:Mg,Ti (TLD-100) was used to calibrate the TL reader and as a reference in comparison of the TL properties of the new materials. The dependence of the responses of the new materials on 60Co dose is linear in the range of 1–1000 Gy. The TL yields of both of the co-doped glasses and TLD-100 are greater for electron irradiation than for photon irradiation. The TL sensitivity of LKB:Ti,Mg is 1.3 times higher than the sensitivity of LKB:Cu,Mg and 12 times less than the sensitivity of TLD-100. The new TL dosimetric materials have low effective atomic numbers, good linearity of the dose responses, excellent signal reproducibility, and a simple glow curve structure. This combination of properties makes them suitable for radiation dosimetry
Arabic gum acacia improves diabetic peripheral neuropathy in rats: a biochemical and histopathological evidence
Background: Diabetic peripheral neuropathy (DPN) is a frequent complication of diabetes mellitus and unfortunately, its present therapeutic alternatives are exceptionally poor. Objectives of this study was to assess the antidiabetic, antioxidant and hypolipidemic action of Gum Arabic (GA) and its role in promoting the functional recovery from diabetic neuropathy developed in in an experimental model of diabetic neuropathy.Methods: Sixty adult male Sprague-Dawley rats were utilized and randomly assigned into six groups (n= 10); control, Arabic gum-treated, untreated diabetic, diabetic received metformin, diabetic received metformin and B12 vitamin and diabetic received metformin, B12 vitamin and AG. Locomotor activity and hyperalgesia were assed at the end of the study. Fasting and two hours post-prandial blood glucose, serum insulin levels, lipid Profile, oxidants/antioxidants parameters were assessed in the blood. Sciatic nerve was assessed histopathologically.Results: The locomotor activity of the untreated diabetic rats was significantly (p<0.001) reduced compared to the control group while it was significantly increased in all treated groups. The lipid profile and Malondialdehyde were significantly improved in all treated groups. Levels of CAT, GSH, SOD, GPx were significantly decreased in untreated diabetic group compared to the control while they were significantly increased in all treated groups compared to the untreated diabetic group. Sciatic nerve fibers of untreated diabetic rats showed degenerated axons with dilated myelin sheaths and degenerated Schwann cells. The nerve had significantly fewer fiber compared to the control. These changes were alleviated in all the treated groups specifically that received metformin, vitamin B12 and GA.Conclusions: It could be concluded that Arabic gum had hypoglycemic, antioxidant and hypolipidemic activity and had a protective effect on diabetic neuropathy. Based on this it is recommended that human clinical trials are necessary to prove this therapeutic effect
The beneficial roles of insulin and parathyroid hormones in the treatment of experimentally induced diabetic osteoporosis in female rats: bone mineral density, morphometric and histological studies
Background: Diabetes mellitus (DM) and osteoporosis are two frequent medical conditions with an increasing prevalence in elderly people and are responsible for large number of incurable fractures. This study is designed experimentally in female rats in order to determine whether combined treatment of insulin and parathyroid hormone (PTH) enhances the reversibility of the osteoporotic changes that occurred in streptozotocin (STZ)-induced DM.
Materials and methods: In this study, 30 adult female rats aged 3 months were used, they were randomly divided into: control group (6 rats) and diabetes group (24 rats), in which experimental DM was induced by i.p. injection of a single dose of STZ (60 mg/kg/body weight). Diabetic group was further divided into four subgroups (6 rats each): non-treated diabetic, insulin-treated (8–12 units s.c./day of Humalin U-40), PTH-treated (6.0 μg s.c./kg/day) and combined insulin and PTH-treated subgroups. All tested groups were assessed for body weight, food and water consumptions.
Results: At the end of the experimental period, the bone mineral density (BMD) was measured for all rats of different groups; then the rats were sacrificed and blood samples were collected for measuring glucose, alkaline phosphatase and osteocalcin levels. Right femora were dissected out and subjected to measurement of diameter of neck and shaft, length of shaft, and weight. Then the femora specimens were processed and stained with haematoxylin and eosin for histological study. The results showed that there was a statistically significant, decrease in BMD, increase in the level of alkaline phosphate, and decrease in the level of osteocalcin in rats in diabetic group compared with other groups; these parameters improved in other groups, especially in diabetes/insulin/PTH group. The rats in diabetic group showed statistically significant decrease in neck and shaft diameters and weight of femur bone compared with other groups, while rats in diabetes/insulin/PTH group showed a significant improvement of these parameters. In diabetic group, there were different histopathological changes in cortical bone and Haversian canals, which improved in other groups, especially in rats in diabetes/insulin/PTH group.
Conclusions: The untreated DM resulted in dramatic reduction in BMD and morphometric parameters. Treatment with insulin ameliorated these effects to some extent, while PTH co-treatment had a more positive effect. The combination of PTH and insulin resulted in stronger improvement of all parameters to approximately like those of control rats
Protective effect of garlic extract against maternal and foetal cerebellar damage induced by lead administration during pregnancy in rats
Background: In spite of its industrial usefulness and varied daily uses, lead (Pb) pollution is a widespread ecological problem that faces the humans in the 21th century. Pb was found to produces a wide range of toxic effects including neurotoxicity especially to the developing and young offspring. Recently, the utilisation of herbal plants has received a significant attention where there has been rising awareness in their therapeutic use; among these is the garlic. In light of the above, the current study is designed experimentally in female pregnant rats in order to investigate the beneficial role of garlic extract in the protection from the maternal and foetal cerebellar damage produced by administration of different doses of Pb during pregnancy.
Materials and methods: Positively pregnant female rats were divided into five groups; one control group, two Pb-treated groups (exposed to 160 and 320 mg/kg b.w. of Pb, respectively) and two groups treated with both Pb and garlic (exposed to Pb as previous groups together with 250 mg/kg b.w./day of garlic extract). Treatments started from day 1 to day 20 of pregnancy, where the mother rats of different experimental groups were sacrificed to obtain the foetuses. Pb level in the maternal and foetal blood and cerebellum was estimated by spectrophotometry. Specimens of the cerebellum of different mother and foetal groups were processed to histological and immunohistochemical staining for microscopic examination.
Results: The results showed that administration of Pb to pregnant rats resulted in a dose-dependent toxicity for both mothers and foetuses in the form of decrease in maternal weight gain, placental and foetal weights, brain weight and diminished foetal growth parameters, which were prominent in rat’s group treated with larger dose of Pb. In Pb-treated rats, Pb level in blood and cerebellum was high when compared with the control group. The histopathological examination of the cerebellum of treated dams and foetuses showed marked alterations mainly in the form of Purkinje cell degeneration and lack of development of foetal cerebellum. Co-treatment of garlic extract along with Pb resulted in a significant decrease in Pb levels as compared with those treated with Pb alone with improvement of the histopathological changes.
Conclusions: This study was useful in evaluating the hazardous effects of uncontrolled use of Pb in general and in assessing the developmental and neurotoxicity of foetuses due to exposure during pregnancy in particular. Co-administration of garlic has beneficial effects in amelioration of Pb-induced neurotoxicity and reversing the histopathological changes of the cerebellum of mother rats and foetuses. (Folia Morphol 2018; 77, 1: 1–15
Effects of Text-messaging on the Academic Writing of Arab EFL Students
This paper investigates the effect of text-messaging on Arab EFL learners’ English academic writing. It also investigates teachers’ attitudes and reactions to the presence of e-texting features in their students’ writing. Qualitative and quantitative methods of analysis were employed on data obtained from the following sources: (1) a sample of freshman students’ writing, (2) a survey investigating students’ use of e-chatting in Arabic and English, and (3) a questionnaire eliciting teachers’ reactions to students’ use of texting features in academic writing. The data were collected from a student sample of the Arab Open University (AOU). The research findings show that Arab EFL students’ writing does not reveal a heavy use of texting features, which suggests that this phenomenon neither poses a serious threat nor adversely impacts students’ written English
Structure-activity relationships and molecular docking studies of chromene and chromene based azo chromophores
The design of novel materials with significant biological properties is a main target in drug design research.
Chromene compounds represent an interesting medicinal scaffold in drug replacement systems. This report illustrates a successful synthesis and characterization of two novel series of chromene compounds using multi-component reactions. The synthesis of the first example of azo chromophores containing chromene moieties has also been established using the same methodology. The antimicrobial activity of the new molecules has been tested against seven human pathogens including two Gm+ve, two Gm-ve bacteria, and four fungi, and the results of the inhibition zones with minimum inhibitory concentrations were reported as compared to reference drugs. All the designed compounds showed significant potent antimicrobial activities, among of them, four potent compounds 4b, 4c, 13e, and 13i showed promising MIC from 0.007 to 3.9 μg/mL. In addition, antiproliferative analysis against three target cell lines was examined for the novel compounds. Compounds 4a, 4b, 4c, and 7c possessed significant antiproliferative activity against three cell lines with an IC50 of 0.3 to 2 μg/mL. Apoptotic analysis was performed for the most potent compounds via caspase enzyme activity assays as a potential mechanism for their antiproliferative
effects. Finally, the computational 2D QSAR and docking simulations were accomplished for structure-activity relationship analyses
Dosimetric characteristics of a LKB:Cu,Mg solid thermoluminescence detector
We present the main thermoluminescence characteristics of a newly borate glass dosimeter modified with lithium and potassium carbonate (LKB) and co-doped with CuO and MgO. An enhancement of about three times has been shown with the increment of 0.1mol% MgO as a co-dopant impurity. The effects of dose linearity, storage capacity, effective atomic number and energy dose response are studied. The proposed dosimeter shows a simple glow curve, good linearity up to 103 Gy, close effective atomic number and photon energy independence. The current results suggest using the proposed dosimeter in different dosimetric applications
Influence of maturity stages on postharvest physico-chemical properties of grapefruit (Citrus paradisi var. ‘Shamber Tarnab’) under different storage durations
The present study was conducted to evaluate the effect of maturity stages on the physicochemical characteristics of grapefruit (Citrus paradisi cv. ‘Shamber Tarnab’) under storage conditions for 60 days at ambient temperature (16±1 °C with 55-60% relative humidity). Grapefruits were harvested at different maturity stages, namely mature green (MG) and full ripe (FR). The fruits of both stages were assessed for different physical quality parameters at 15 days interval. The experimental results showed that ascorbic acid content, titratable acidity, fruit firmness, percent disease incidence was higher at FR stage. In contrast, weight loss, percent juice content, total soluble solid (TSS), and TSS/acid ratio at MG (mature green) were lower than that of FR fruits. Regarding storage durations, the fruit firmness, titratable acidity, percent juice content, ascorbic acid content decreased significantly, whilst total soluble solid, TSS/Acid ratio, weight loss, and percent disease incidence increased significantly with the extension of storage duration from 0 to 60 days. As concerned to its interactive effects, the highest ascorbic acid content, titratable acidity, percent juice content, and maximum fruit firmness were observed in fresh grapefruit, harvested at (MG) mature green stages, whereas the maximum total soluble solid, percent disease incidence, and TSS/Acid ratio were recorded in fruit harvested at (FR) full ripe stage, stored for 60 days at room temperature. Similarly, the Pearson’s Correlation Analysis (p> 0.05) of grapefruit was positive effect for most of the quality traits of grapefruit at different storage durations and maturity stages. It was concluded that grapefruit could be harvested at the mature green stage (MG) for sustaining quality attributes up to 60 days of storage at room temperature
Binary nickel and silver oxides by thermal route: preparation and characterization
Many studies have concentrated on exploring behaviors of nickel silver oxide nanoparticles using various routes of fabrication. Thermal treatment technique has never been utilized to fabricate nickel oxide silver oxide nanoparticles. In this research, binary (NiO)0.4 (Ag2O)0.6 nanoparticles were synthesized using the thermal treatment method due to its attractive advantages such as low cost, eco-friendly, and purity of nanoparticles. The structural, morphological, and optical behaviors of these nanoparticles were investigated at different calcined temperatures. X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible spectroscopy (UV–Vis), and photoluminescence (PL) were the techniques used to characterize the synthesized nanoparticles. XRD was conducted at different calcined temperatures. The crystallite size was increased from 25.4 nm to 37.0 nm as the calcined temperature increased from 500 °C to 800 °C. Also, TEM results verified that the mean particle size was enlarged as the calcined temperatures increased. Two band gaps were found for each temperature, which were decreased from (3.05, 2.45) to (2.70, 1.95) eV as the temperature varied from 500 to 800 °C, respectively. Broadbands were observed by PL spectra, and the intensity of two emission peaks was also increased at higher temperatures. The results approved the successful formation of binary (NiO)0.4 (Ag2O)0.6 nanoparticles by a novel facile synthesis route. These nanoparticles are likely to have various applications, especially optical applications due to the formation of two band gaps
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