Finite element analysis of gradient coil deformation and vibration in NMR microscopy

Resolution degradation due to gradient coil deformation and vibration in NMR microscopy is investigated using finite element analysis. From the analysis, deformations due to the Lorentz force can be as large as 1-10 μm depending on the gradient strength and coil frame material. Thus, these deformations can be one of the major resolution limiting factors in NMR microscopy. Coil vibration, which depends on the input current waveform and resolution degradation due to time-variant deformation and time-invariant deformation are investigated by numerical simulations

Solid phase extraction and LC-MS/MS quantification of ibandronate in human plasma

Purpose: To develop and validate a simple, highly sensitive and accurate method for the quantification of ibandronate (IBN) in human plasma.Methods: Electrospray ionization liquid chromatography tandem mass spectrometry (LC-MS/MS) in positive ion mode was applied to obtain optimum signals. The parent ion was acquired under collisionactivated dissociation conditions, and the abundant fragments used to design multiple reaction monitoring experiments for monitoring two ibandronate transitions (m/z 376 to m/z 114, and m/z 376 to m/z 250). The IBN was isolated from plasma with weak anion exchange solid phase extraction columns with ‘on-cartridge’ derivatization using tri-methylsilyl-diazomethane (TMSDZ) reagent to convert IBN to tetra-methyl derivative.Results: The studied drug was successfully extracted from plasma samples without any interference at a retention time of 3.2 min. The matrix effect averaged 110 %, indicating that endogenous materials had little effect on ionization. The relationship between plasma analyte concentration and IBN signal area was satisfactorily linear, with correlation coefficient (r2) ranging from 0.9817 to 0.9942 in the concentration range of 0.5 – 200 ng/ml. The lower and upper limits of quantification (LLOQ and ULOQ) for IBN were 0.5 and 200 ng/ml, respectively. Relative recovery of IBN from plasma after extraction and derivatization at 3 distinct concentrations was 83.93 to 85.06 %, relative to standard solutions. The ranges of intra- and inter-day accuracies of quantification of quality controls were 89.39 - 106.40 %, and 90.50 - 107.96 %, respectively. Processed plasma IBN extracts were stable in autosampler at 4 0C (91.12 to 103.49%). Long-term stability in plasma after 30 days at -24 0C ranged from 89.52 to 113.18 %.Conclusion: This validated LC-MS/MS method can be successfully applied for determination of IBN in pharmacokinetic studies. It is a sensitive and specific assay for plasma IBN in bioequivalence studies. Keywords: Ibandronate, LC-MS/MS, Validation, Derivatization, Solid-phase extractio

Evaluating the In vivo Efficacy of Copper-Chitosan Nanocomposition for Treating Vascular Wilt Disease in Date Palm

Date palm, Phoenix dactylifera, as one of the most important fruit crops in Egypt and many other countries, can be affected by many fungal diseases, among which the vascular wilt disease, caused by the fungal pathogen Fusarium oxysporum, is considered the most deteriorating one. This study aims at evaluating the efficiency of Copper-Chitosan Nanopcomposition for treating the vascular wilt disease in date palm. The study relies mainly on beleaguering the disease via the double-role functionality of copper-chitosan nanocomposition, i.e. its potential antifungal effect on the fungal pathogen, besides its capability to enhance the immune responses of the infected plant. In this regard, chitosan nanoparticles were prepared according to the ionic gelation method, whereas copper nanoparticles were prepared according to the chemical reduction method. Physicochemical characterization of both chitosan and copper nanoparticles was performed using dynamic light scattering (DLS), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD). Copper-chitosan nanocomposition could significantly reduce the vascular wilt disease severity; this means that the nanocomposition can be used in the future for developing new nano-fungicides to control such pathogens

Role of Goldenberry (Fruits with Husk) Extract in Ameliorating the Architecture and Osmotic Fragility of Red Blood Cells in Obese Rats

Goldenberry (GB) is a promising fruit that can be a constituent in many possible nourishments. No notifications were obtained regarding the impact of exposure to goldenberry extract in the viewpoint of blood rheological properties as well as erythrocyte osmotic fragility of red blood cells (RBCs) in obese rats. A substantial reduction in plasma triglyceride, total cholesterol, and LDL, with a considerable increment in HDL levels relative to the obese group (p≤0.05), was observed in rats receiving low and high doses of GB, accompanied by restoration of SOD activity and GSH levels. Rheological parameters of rats' blood have been studied over a wide range of shear rates (225-1875 s-1). A significant decrease in blood viscosity in rats who received low and high doses of GB extract was compatible with every shear rate compared to the control group. The shear stress values of the obese rats reduced appreciably (p≤0.05) in all values of shear rate (from 75 to 500 s-1) proportional to the control group, while in the groups that received low and high doses of GB extract, shear stress was restored to the control values. Finally, administration of GB extract significantly decreased yield stress and indices of whole blood aggregation, with an extremely substantial increment in flow rate, in rats given low or high doses of GB compared to obese ones. The result also showed a decrease in both the average raised osmotic fragility and the hemolysis rate in rats after supplementation with low and high doses of GB extract

Mortality in Serologically Unconfirmed Mediterranean Spotted Fever [with Reply]

I read with interest the article by Paddock et al. [1], who described the detection of occult mortality due to Rocky Mountain spotted fever (RMSF) by demonstrating Rickettsia rickettsii antigens or DNA in blood and tissues. In Mediterranean countries, including Israel, spotted fever is caused by members of the R. conorii complex, which are antigenically related to R. rickettsii. ... To the Editor -- We appreciate the comments by Yagupsky, which underscore several of the salient features of spotted fever- group rickettsial infections that we emphasized in our report [2]. For patients, diagnosticians, and clinicians faced with the potentially tragic consequences of Rocky Mountain spotted fever or severe Mediterranean spotted fever (MSF), these points merit repeating. First, the nonspecific signs and symptoms early in the course of rickettsial infections mimic many other infectious and noninfectious syndromes. Second, the diagnostic challenges posed by these diseases are compounded by the lack of rapid and widely available confirmatory tests early in the course of the illnesses. Finally, spotted fevers have the potential to kill otherwise healthy persons in ^ week after onset of symptoms, emphasizing the need for early administration of appropriate therapy

Non-locality and Medium Effects in the Exclusive Photoproduction of Eta Mesons on Nuclei

A relativistic model for the quasifree exclusive photoproduction of $\eta$ mesons on nuclei is extended to include both non-local and medium effects. The reaction is assumed to proceed via the dominant contribution of the S$_{11}$(1535) resonance. The complicated integrals resulting from the non-locality are simplified using a modified version of a method given by Cooper and Maxwell. The non-locality effects are found to affect the magnitude of the cross section. Some possibilities reflecting the effects of the medium on the propagation and properties of the intermediate S$_{11}$ resonance are studied. The effects of allowing the S$_{11}$ to interact with the medium via mean field scalar and vector potentials are considered. Both broadening of width and reduction in mass of the resonance lead to a suppression of the calculated cross sections.Comment: 19 pages, 7 figure

POTENTIAL ROLE OF MILK THISTLE SEED AND ITS OIL EXTRACTS AGAINST HEART AND BRAIN INJURIES INDUCED BY γ-RADIATION EXPOSURE

Objective: This study aimed to investigate the protective effect of Silybum marianum (S. marianum) seeds extract its oil fraction against damage effect of γ-radiation in female albino rats.Methods: Ultrasonic-assisted extraction was used for the extraction of S. marianum seeds. Lipid patterns of S. marianum seeds oil were elucidated using gas chromatography-mass spectrometry (GC-MS). S. marianum seeds extract was analyzed using high-performance liquid chromatography (HPLC). Malondialdehyde (MDA), reduced glutathione (GSH) and metallothionein (MT) were estimated in heart and brain tissues of the examined rats. Lactate dehydrogenase (LDH) and creatine kinase-MB (CKMB) were measured in the serum of the examined rats, and the brain biomarkers; dopamine and serotonin were also measured.Results: The oil was found to be rich in linoleic acid (58.20%) and arachidic acid (23.38%). S. marianum seeds extract revealed the presence of taxifolin and six main active constituents of silymarin, including silydianin, silychristin, silybin A, silybin B, isosilybin A and isosilybin B. Treatment of γ-radiation damage effect using S. marianum seeds extract and its oil fraction led to a significant reduction of MDA levels in heart (139.6 and 165.5 nmol/g, respectively) and brain (158.5 and 135.2 nmol/g, respectively) tissues, however, significant increase of GSH levels in heart (316.4 and 293 mg/g, respectively) and brain (210.4 and 227 mg/g, respectively) tissues was observed, also a significant increase of dopamine levels (85.27 and 65.74 ng/g, respectively) and MT levels of heart tissues (108.5 and 70.52 mg/g, respectively) was observed.Conclusion: S. marianum seeds extract and its oil fraction showed a protective effect against γ-radiation-induced damage in heart and brain.Â