Structural, optical and magnetic properties of nanostructured Cr-substituted Ni-Zn spinel ferrites synthesized by a microwave combustion method

Nanoparticles of Cr3+-substituted Ni-Zn ferrites with a general formula Ni0.4Zn0.6-xCrxFe2O4 (x = 0.0 - 0.6) have been synthesized via a facile microwave combustion route. The crystalline phase has been characterized by XRD, TEM, FT-I and XPS revealing the spinel ferrite structure without extra phases. Crystallite sizes of 23 - 32 nm as estimated by XRD analyses, after corrections for crystal stains by Williamson-Hall method, are comparable to the average particle sizes observed by TEM which indicates successfully synthesized nanocrystals. Rietveld refinement analyses of the XRD patterns have inferred a monotonic decrease behavior of the lattice parameter with Cr doping in agreement with Vegard's law of solid solution series. Furthermore, cations distribution with an increased inversion factor indicate the B-site preference of Cr3+ ions. The oxidation states and cations distribution indicated by XPS results imply the Cr3+ doping on the account of Zn2+ ions and a partial reduction of Fe3+ to Fe2+ to keep the charge balance in a composition series of (Ni2+)0.4(Zn2+, Cr3+)0.6(Fe2+, Fe3+)2(O2-)4. The optical properties were explored by optical UV-Vis spectroscopy indicating allowed direct transitions with band gap energy that decreases from 3.9 eV to 3.7 eV with Cr doping. Furthermore, the photocatalytic activity for the degradation of methyl orange (MO) dye was investigated showing largely enhanced photodecomposition up to 30% of MO dye over Ni0.4Cr0.6Fe2O4 for 6 hours. A vibrating sample magnetometry (VSM) measurements at room temperature show further enhancement in the saturation magnetization of Ni0.4Zn0.6Fe2O4 , the highest in Ni-Zn ferrites, from about 60 to 70 emu/g with the increase of Cr concentration up to x = 0.1, while the coercivity shows a general increase in the whole range of Cr doping.Comment: 21 page, 9 figure

Molecular Characterization, Developmental Expression and Immunolocalization of Clathrin Heavy Chain in the Ovary of the American Cockroach, Periplaneta Americana During Oogenesis

Clathrin is the principal protein involved in receptor mediate endocytosis and the main component of the coated vesicles. It is composed of three identical clathrin heavy chains (CHC), each with an attached light chain. We characterized the deduced amino acid sequence of the partial cDNA clone of the American cockroach, Periplaneta americana (Pam) CHC. The analysis showed that this sequence is represented as multiple alpha helical repeats occurred in the arm region of the CHC and displayed a high level of identity and similarity to mosquitoes and Drosophila melanogaster CHCs. This is the first report on CHC from a hemimetabolous insect. The amplified CHC probe could hybridize two CHC transcripts in the current preparations, 6.3 kb and 7.3 kb. The Northern blot analysis confirmed that a 6.3 kb transcript is specifically expressed in ovarian tissues at high levels throughout the ovarian development, especially in previtellogenic ovaries (Days 1-4) but dropped during the vitellogenic period (days 5-7) and ultimately no transcript was detected in fully vitellogenic ovaries (days 9-13). Immunoblot analysis detected an ovary specific CHC protein of ~175 kDa that was present in previtellogenic ovaries on the day of female emergence and after initiation of vitellogenesis and onset of Vg uptake. Immunocytochemistry localized CHC protein to germ-line derived cells, oocytes, and revealed that CHC translation begins very early during oocyte differentiation in the germarium. The present work suggested a possible role for clathrin in the early fluid phase endocytosis (pinocytosis) in addition to its role in receptor-mediated endocytosis

Physical Properties of Polyacrylamide/Polyvinylalcohol Silica Nanocomposites

 In this paper, samples of Polyacrylamide (PAAm) nanosilica nanocomposites were prepared having different concentration of nanosilica (0.125, 0.25, and 0.5). Polyacrylamide (PAAm) and poly (vinyl alcohol) (PVA) were blended with different ratio (3/1, 1/1, 1/3) using solution-cast technique. The prepared films were characterized by Fourier transform infrared (FTIR), X-ray diffractions (XRD) and scanning electron microscopy (SEM). FTIR spectra showed the presence of hydrogen bonding between–CONH2 groups in PAAm and –OH group in PVA and confirm the hydrophilic nature of the blends. X-ray diffractions shows the presence of a strong broad peak centered at 22º (2θ) confirms the amorphous nature of silica which is supposed to be the characteristic of SiO2. The results obtained from different experimental techniques were supported by SEM image analysis. The thermal stability of the nanocomposites enhanced by increasing the silica content in the blend. The DC electrical conductivity was studied for all prepared samples. It was found that the conductivity increase by increasing silica content as well as, increased by increasing the wt% of PVA

The Effect of Probiotics Supplementation on Fecal Calprotectin as an Early Marker of Neonatal Enteropathy

Abstract. Objectives. Evaluationof the effect of probiotic supplementation on fecal calprotectin levels which was tested as an early marker of necrotizing enterocolitis (NEC) and sepsis in neonates. Patients and Methods. A prospective, double blind, randomized, controlled clinical trial was conducted in 30 neonates who were examined for fecal calprotectin (FCP) levels. neonates are divided into two groups, the group I consisted of 15 neonates who were given probiotics (Probiotics group) and group II consisted of 15 neonates who were not given probiotics(nonprobiotic group), both groups were followed up and observed until reach full feeding for the occurrence of necrotizing enterocolitis (NEC), feeding intolerance and sepsis. Results. FCP levels were higher in neonates of group II (non-probiotics group) than neonates of group I (Probiotics group) after 2 weeks of probiotic supplementation in neonates of group I (190.5+ 86.9 versus 38.4 + 32.2) and significant Correlation between the level of FCP and Enteropathy in group I showing + ve correlation and p-value<0.05 with p-value is (0.029,0.024,0.019) at the onset of research and after 1 wk and after 2 wks respectively and Cutoff point of the FCP on which enteropathy occurred was 482 μg/g. Conclusions. The use of probiotics in neonates could decrease the incidence of NEC and sepsis and FCP could be used as an early predictor of NEC in neonates for early prevention and treatment with better prognosis and outcome [Mohamed S El Frargy, Azza M. Hassan. The Effect of Probiotics Supplementation on Fecal Calprotectin as an Early Marker of Neonatal Enteropathy

Levels of certain tumor markers as differential factors between bilharzial and non-biharzial bladder cancer among Egyptian patients

<p>Abstract</p> <p>Background/Objective</p> <p>Bladder cancer is the commonest type of malignant tumors as a result of schistosomaisis which is a major healthy problem in many subtropical developing countries. The aim of this study is to comparatively elucidate the underlying biochemical tumor markers in schistosomal bladder cancer versus non-schistosomal bladder cancer when compared to normal healthy ones.</p> <p>Methods</p> <p>This work was performed on tissue specimens from total 25 patients and serum samples from total 30 patients versus ten healthy individuals served as control. The investigated parameters in serum are: xanthine oxidase (XO), fructosamine, lactate dehydrogense (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total proteins, essential and non- essential amino acids profile, hydroxyproline, total immunoglobulin E (IgE) and tumor necrosis factor alpha (TNF-<it>α</it>). In addition, the current investigation also extended to study some markers in tumor bladder tissues including, pyruvate kinase enzyme (PK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT).</p> <p>Results</p> <p>Results showed that biharzial bladder cancer patients recored more significant elevation in serum XO, fructosamine, LDH, AST, ALT, hydroxyproline, IgE and TNF-<it>α </it>than in bladder cancer patients when compared to control ones. While, in tissues there were significant increase in PK, LDH, AST & ALT activities of schistosomal bladder cancer than in bladder cancer as compared to control healthy patients.</p> <p>Conclusions</p> <p>It could be concluded that, bilharzial and non-bilharzial bladder cancer showed distinct biochemical profile of tumor development and progression which can be taken into consideration in diagnosis of bladder cancer.</p

Molecular characterization, developmental expression and immunolocalization of clathrin heavy chain in the ovary of the American cockroach, Periplaneta americana during oogenesis

Clathrin is the principal protein involved in receptor mediate endocytosis and the main component of the coated vesicles. It is composed of three identical clathrin heavy chains (CHC), each with an attached light chain. We characterized the deduced amino acid sequence of the partial cDNA clone of the American cockroach, Periplaneta americana (Pam) CHC. The analysis showed that this sequence is represented as multiple alpha helical repeats occurred in the arm region of the CHC and displayed a high level of identity and similarity to mosquitoes and Drosophila melanogaster CHCs. This is the first report on CHC from a hemimetabolous insect. The amplified CHC probe could hybridize two CHC transcripts in the current preparations, 6.3 kb and 7.3 kb. The Northern blot analysis confirmed that a 6.3 kb transcript is specifically expressed in ovarian tissues at high levels throughout the ovarian development, especially in previtellogenic ovaries (Days 1-4) but dropped during the vitellogenic period (days 5-7) and ultimately no transcript was detected in fully vitellogenic ovaries (days 9-13). Immunoblot analysis detected an ovary specific CHC protein of ~175 kDa that was present in previtellogenic ovaries on the day of female emergence and after initiation of vitellogenesis and onset of Vg uptake. Immunocytochemistry localized CHC protein to germ-line derived cells, oocytes, and revealed that CHC translation begins very early during oocyte differentiation in the germarium. The present work suggested a possible role for clathrin in the early fluid phase endocytosis (pinocytosis) in addition to its role in receptor-mediated endocytosis