Synthesis, characterization and microstructural evaluation of ZnO nanoparticles by William-Hall and size-strain plot methods

ABSTRACT. At various calcination temperatures 450, 550 and 650 °C, zinc oxide nanoparticles were produced. Calcinated ZnO has high surface area as the BET was 119.12 m2g–1 and the average particle radius was calculated to be 1.16 nm. The dimension of crystallites and straining in ZnO nanoparticles' diffraction peaks remained measured. The Williamson–Hall (W–H) technique besides the size–strain approach stayed used. For each of XRD reflection peaks, physical characteristics like strain and stress were computed. Towards regulate the magnitude of crystallites, the Williamson–Hall (W–H) approach besides the size–strain technique are used that is good agreement with the size that determine from SEM as it was 22.6, 26.6 and 32.6 nm for ZnO calcinated at 450, 550 and 650 oC, individually. Using the W–H plot to modify the subversion shape, assuming an unvarying distortion model (UDM), unvarying stress deformation model (USDM), unvarying deformation energy density model (UDEDM), and The size–strain plan (SSP) approach was used to determine this. The SEM and Scherrer methods match well with the crystal size of ZnO NPs determined using W–H plots and the SSP technique.     KEY WORDS: Zinc oxide nanosphere, Calcination, Physical characterization, W–H investigation, SSP technique Bull. Chem. Soc. Ethiop. 2022, 36(4), 815-829.                                                           DOI: https://dx.doi.org/10.4314/bcse.v36i4.8                                                       &nbsp

Weibull-Linear Exponential Distribution and Its Applications

In this article, a new four-parameter lifetime distribution, namely, the Weibull-Linear exponential distribution is defined and studied. Several of its structural properties such as quartiles, moments, mean waiting time, mean residual lifetime, Renyi entropy, mode, and order statistics are derived. Based on the idea of the Weibull T − X family, the new density function of this model is developed. The model parameters, as well as some of the lifetime parameters (reliability and failure rate functions), are estimated using the maximum likelihood method. Asymptotic confidence intervals estimates of the model parameters are also evaluated by using the Fisher information matrix. Moreover, to construct the asymptotic confidence intervals of the reliability and failure rate functions, we need to find their variance of them, which are approximated by the delta method. A real data set is used to illustrate the application of the Weibull-Linear Exponential distribution

siRNA blocking of mammalian target of rapamycin (mTOR) attenuates pathology in annonacin-induced tauopathy in mice

Tauopathy is a pathological hallmark of many neurodegenerative diseases. It is characterized by abnormal aggregates of pathological phosphotau and somatodendritic redistribution. One suggested strategy for treating tauopathy is to stimulate autophagy, hence, getting rid of these pathological protein aggregates. One key controller of autophagy is mTOR. Since stimulation of mTOR leads to inhibition of autophagy, inhibitors of mTOR will cause stimulation of autophagy process. In this report, tauopathy was induced in mice using annonacin. Blocking of mTOR was achieved through stereotaxic injection of siRNA against mTOR. The behavioral and immunohistochemical evaluation revealed the development of tauopathy model as proven by deterioration of behavioral performance in open field test and significant tau aggregates in annonacin-treated mice. Blocking of mTOR revealed significant clearance of tau aggregates in the injected side; however, tau expression was not affected by mTOR blockage

PROTECTIVE EFFECTS OF ZINGIBER OFFICINALE AGAINST CARBON TETRACHLORIDE INDUCED LIVER FIBROSIS

Objective: Liver plays a pivotal role in regulating various physiological processes in the body such as metabolism, secretion, and storage. It has a great capacity to detoxify toxic substances and synthesize useful principles. The current study was designed to investigate the possible protective effects of Zingiber officinale (ginger) extract on liver fibrosis induced by carbon tetrachloride (CCl4) in rats.Methods: The animals were divided into four groups with eight rats in each. To induce liver fibrosis, Wistar albino rats received CCl4 (2 ml/kg diluted in corn oil) twice weekly for eight weeks. Rats were concurrently treated with Z. officinale extract at two different doses (300 and 600 mg/kg/day).Results: CCl4 ­­induced liver injury characterized by fibrotic changes, degenerated hepatocytes and focal accumulation of inflammatory cells. In addition, CCl4 administration produced a significant increase in serum aminotransferases, lipids, liver lipid peroxidation and nitric oxide. The hepatoprotective effects of Z. officinale extract were evidenced by the significant decrease in serum aminotransferases and liver lipid peroxidation. Further, concurrent treatment with either dose of Z. officinale enhanced liver glutathione and enzymatic antioxidant defenses.Conclusion: Z. officinale showed a marked hepatoprotective effect against CCl4–induced liver fibrosis and injury through the abolishment of oxidative stress and potentiation of the antioxidant defense system.Keywords: Antioxidant, Ginger, Fibrosis, Oxidative stres

PROTECTIVE EFFECT OF AQUEOUS EXTRACT POMEGRANATE PEEL AGAINST STERIGMATOCYSTIN TOXICITY IN RAT

Introduction and Aim: Sterigmatocystin (Stg) a mycotoxin with mutagenic and carcinogenic properties is commonly found as the contaminant in grains and animal feeds. Pomegranate peel is a rich source of antioxidants, flavonoids and other phenolic compounds. So the aim of the current study was to evaluate the protective effects of aqueous extract of red Pomegranate peel against Stg toxicity in liver, kidney, intestine and lung as well as final body weight using male rats. Methods: Forty eight Sprague-Dawley male rats were divided into six groups (8rats/group) including the control group that fed on a standard diet and water without any treatment, group 2 fed on standard diet plus aqueous extract of RPP (250 mg/rat/day), group 3 fed on standard diet plus aqueous extract of RPP (500 mg/ rat/day), group 4 fed on a standard diet and orally Stg. dissolved at a dose (18µg/rat/day), group 5 fed on a standard diet and Stg  plus aqueous extract of RPP (250mg/day) and group 6 fed on a standard diet and Stg. plus aqueous extract of RPP (500mg/day). At the end of the experimental period, blood samples were collected for serum biochemical analyses. After collecting the blood samples all animals were scarified and dissected samples of liver, kidney, intestine and lung were collected for histological examination. Results: The total phenols and total flavonoids, compounds in aqueous extract of RPP were 1.38 mg/ml and 680.28 mg/ml, respectively. However, the antioxidant activity amounted to 68.0% in the determination of radical DPPH scavenging activity. On the other hand, results indicated that rat orally Stg plus aqueous extract of RPP with low dose and high doses showed a significant improvement in final body weight compared with group administrated of Stg alone. While, the effect of aqueous extract of RPP on kidney and liver function of rats, the results indicated that the rat orally Stg alone caused significant increased in urea, creatinine and uric acid compared with the control group. The aqueous extract of RPP alone at the two tested doses did not induce any significant changes in the biochemical parameters or the histological picture. The combined treatment showed significant improvements in all tested parameters and histological pictures in the liver tissues. Moreover, this improvement was more pronounced in the group received the high dose of aqueous extract of RPP. Conclusion: From results it can be concluded that u the aqueous extract of RPP has a potent antioxidant activity and a protective effect against Stg toxicity and this protection was dose dependent. Keywords: Sterigmatocystin, Red pomegranate peels (RPP), aqueous extract, liver and kidney

Efficient adsorption of Rhodamine B using a composite of Fe3O4@zif-8: Synthesis, characterization, modeling analysis, statistical physics and mechanism of interaction

ABSTRACT. The utilization of a metal organic framework (ZIF-8) modified by Fe3O4 nanoparticles was used to accomplish adsorption of Rhodamine B (RB) from aqueous solutions. SEM, XRD, IR, and BET analyses were all used to characterize the composite (Fe3O4@ZIF-8). The surface area of this adsorbent was 478.4 m2/g. X-Ray diffraction spectroscopy was used to detect surface modification utilizing electron microscopy (SEM) scanning with 48 nm in diameter average particle size according to a statistical physics method. Fe3O4@ZIF-8 appears to have dispersive interactions and pore characteristics, according to quantum chemistry simulations. On the adsorption of RB, the influences of contact time, adsorbent quantity, dye concentration, and temperature were studied. The Langmuir and Freundlich adsorption isotherm models were used to study the adsorption isotherms. Anticipated overall adsorption potential was 647.5 mg/g, with a zero-charge point (pHPZC) of 4.3. The adsorption isotherm was fitted using Langmuir whereas pseudo second order was used to match the kinetics. Energy of adsorption (Ea) is 28.7 kJ/mol, indicating a chemisorption phase. The adsorption process is endothermic and unpredictable, according to thermodynamic experiments. It was also looked into using ethanol as a solvent in the desorption of deposited cationic dye.   KEY WORDS: Fe3O4@ZIF-8, Rhodamine B, Adsorption models, Thermodynamics   Bull. Chem. Soc. Ethiop. 2023, 37(1), 211-229.                                                                DOI: https://dx.doi.org/10.4314/bcse.v37i1.17                                                     &nbsp

Medical prospects of cryptosporidiosis in vivo control using biofabricated nanoparticles loaded with Cinnamomum camphora extracts by Ulva fasciata

Background and Aim: Global efforts are continuing to develop preparations against cryptosporidiosis. This study aimed to investigate the efficacy of biosynthesized Ulva fasciata loading Cinnamomum camphora oil extract on new zinc oxide nanoparticles (ZnONPs shorten to ZnNPs) and silver nanoparticles (AgNPs) as alternative treatments for Cryptosporidium parvum experimental infection in rats. Materials and Methods: Oil extract was characterized by gas chromatography-mass spectrometry, loaded by U. fasciata on ionic-based ZnO and NPs, and then characterized by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. Biosafety and toxicity were investigated by skin tests. A total of 105 C. parvum oocysts/rat were used (n = 81, 2–3 W, 80–120 g, 9 male rats/group). Oocysts shedding was counted for 21 d. Doses of each preparation in addition to reference drug were administered daily for 7 d, starting on post-infection (PI) day (3). Nitazoxanide (100 mg) was used as the reference drug. After 3 weeks, the rats were sacrificed for postmortem examination and histopathological examination. Two blood samples/rat/group were collected on the 21st day. Ethylenediaminetetraacetic acid blood samples were also used for analysis of biochemistry, hematology, immunology, micronucleus prevalence, and chromosomal abnormalities. Results: C. camphora leaves yielded 28.5 ± 0.3 g/kg oil and 20 phycocompounds were identified. Spherical and rod-shaped particles were detected at 10.47–30.98 nm and 18.83–38.39 nm, respectively. ZnNPs showed the earliest anti-cryptosporidiosis effect during 7–17 d PI. Other hematological, biochemical, immunological, histological, and genotoxicity parameters were significantly fruitful; hence, normalized pathological changes induced by infestation were observed in the NPs treatments groups against the infestation-free and Nitazoxanide treated group. Conclusion: C. camphora, U. fasciata, ZnNPs, and AgNPs have refluxed the pathological effects of infection as well as positively improved host physiological condition by its anticryptosporidial immunostimulant regenerative effects with sufficient ecofriendly properties to be proposed as an alternative to traditional drugs, especially in individuals with medical reactions against chemical commercial drugs

Implication of protein kinase R Gene quantification in hepatitis C Virus Genotype 4 induced Hepatocarcinogenesis

<p>Abstract</p> <p>Background</p> <p>Protein kinase RNA (PKR-regulated) is a double-stranded RNA activated protein kinase whose expression is induced by interferon. The role of PKR in cell growth regulation is controversial, with some studies supporting a tumour suppressor function and others suggesting a growth-promoting role. However, it is possible that the function of PKR varies with the type of cancer in question.</p> <p>Methods</p> <p>We report here a detailed study to evaluate the function of PKR in hepatitis C virus genotype 4 (HCV-4) infected patients. PKR gene was quantitated in HCV related malignant and non-malignant liver tissue by RT-PCR technique and the association of HCV core and PKR was assessed.</p> <p>Results</p> <p>If PKR functions as a tumour suppressor in this system, its expression would be higher in chronic hepatitis tissues. On the contrary our study demonstrated the specific association of HCV-4 with PKR expressed in hepatocellular carcinoma (HCC) tissues, leading to an increased gene expression of the kinase in comparison to chronic hepatitis tissues. This calls into question its role as a tumour suppressor and suggests a positive regulatory role of PKR in growth control of liver cancer cells. One limitation of most of other studies is that they measure the levels rather than the quantitation of PKR gene.</p> <p>Conclusion</p> <p>The findings suggest that PKR exerts a positive role in cell growth control of HCV-4 related HCC, obtaining a cut-off value for PKR expression in liver tissue provides the first evidence for existence of a viral activator of PKR.</p> <p>Virtual Slides</p> <p>The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1267826959682402.</p

Efficiency of Selected Lactic Acid Bacteria Isolated from some Dairy Products on Aflatoxin B1 and Ochratoxin A

Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are two of the most important of mycotoxins associated with tropical and subtropical climate as in Egypt. Therefore, this study aimed to isolated lactic acid bacteria (LAB) and Bifidobacteria from some local dairy products from Egypt and using some strains to reduce/or remove AFB1 and OTA toxins. Fifty samples, of milk and dairy products, including ten samples each, of Kareish, Damietta cheese (soft type), buffalo’s milk, yoghurt (zabady), and naturally acidified milk (Rayeb)were screened for their load of Lactobacilli, Lactococci and Bifidobacteria, using MRS agar, M17 agar and (MRS-Cys) agar, respectively. The obtained data indicated that 38, 31 and 22 isolates belonged to Lactobacillus, Lactococcus and genus Bifidobacterium, respectively. Fourteen strains isolated from LAB and Bifidobacterium were tested on AFB1 and OTA in PBs contaminated by10 ppb with three times incubation periods (6, 12 and 36 hours) at 37°C. The results indicated that all tested strains were able to reduce AFB1 at different rates ranging between 12.1 to 65.4% after incubation for 6 h. These rates increased to 78.8% and 89.9% after incubation at 37°C for 12 and 36h, respectively. The same results were with OTA, where percentages of reduction ranging from 81.4 to 80.4% were obtained when incubation with LAB cells was done at 37°C and prolonged to 36 h. According to the results, the percentage of reduction increased with the increasing time for each strain