Effect of silibinin and trans-chalcone in an Alzheimer's disease-like model generated by insulin amyloids.

Amyloid fibrils are characteristic of several disorders including Alzheimer's disease (AD), with no cure or preventive therapy. Diminishing amyloid deposits using aromatic compounds is an interesting approach toward AD treatment. The present study examined the anti-fibrillogenic effects of silibinin and trans-chalcone in vitro, in vivo, and in silico on insulin amyloids. In vitro incubation of insulin at 37°C for 24 h induced amyloid formation. Addition of trans-chalcone and silibinin to insulin led to reduced amounts of fibrils as shown by thioflavin S fluorescence and Congo red absorption spectroscopy, with a better effect observed for silibinin. In vivo bilateral injection of fibrils formed by incubation of insulin in the presence or absence of silibinin and trans-chalcone or insulin fibrils plus the compounds in rats' hippocampus was performed to obtain AD characteristics. Passive avoidance (PA) test showed that treatment with both compounds efficiently increased latency compared with the model group. Histological investigation of the hippocampus in the cornu ammonis (CA1) and dentate gyrus (DG) regions of the rat's brain stained with hematoxylin-eosin and thioflavin S showed an inhibitory effect on amyloid aggregation and markedly reduced amyloid plaques. In silico, a docking experiment on native and fibrillar forms of insulin provided an insight onto the possible binding site of the compounds. In conclusion, these small aromatic compounds are suggested to have a protective effect on AD.

Radiomic Phenotypes Distinguish Atypical Teratoid/Rhabdoid Tumors from Medulloblastoma.

BACKGROUND AND PURPOSE: Atypical teratoid/rhabdoid tumors and medulloblastomas have similar imaging and histologic features but distinctly different outcomes. We hypothesized that they could be distinguished by MR imaging-based radiomic phenotypes. MATERIALS AND METHODS: We retrospectively assembled T2-weighted and gadolinium-enhanced T1-weighted images of 48 posterior fossa atypical teratoid/rhabdoid tumors and 96 match-paired medulloblastomas from 7 institutions. Using a holdout test set, we measured the performance of 6 candidate classifier models using 6 imaging features derived by sparse regression of 900 T2WI and 900 T1WI Imaging Biomarker Standardization Initiative-based radiomics features. RESULTS: From the originally extracted 1800 total Imaging Biomarker Standardization Initiative-based features, sparse regression consistently reduced the feature set to 1 from T1WI and 5 from T2WI. Among classifier models, logistic regression performed with the highest AUC of 0.86, with sensitivity, specificity, accuracy, and F1 scores of 0.80, 0.82, 0.81, and 0.85, respectively. The top 3 important Imaging Biomarker Standardization Initiative features, by decreasing order of relative contribution, included voxel intensity at the 90th percentile, inverse difference moment normalized, and kurtosis-all from T2WI. CONCLUSIONS: Six quantitative signatures of image intensity, texture, and morphology distinguish atypical teratoid/rhabdoid tumors from medulloblastomas with high prediction performance across different machine learning strategies. Use of this technique for preoperative diagnosis of atypical teratoid/rhabdoid tumors could significantly inform therapeutic strategies and patient care discussions.

Nano-composition of riboflavin-nafion functional film and its application in biosensing.

A novel nafion-riboflavin membrane was constructed and characterized by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy and cyclic voltammetric techniques. The estimated average diameter of the designed nanoparticles was about 60 nm. The functional membrane showed a quasi-reversible electrochemical behaviour with a formal potential of -562 +/- 5 mV (vs Ag/AgCl) on the gold electrode. Some electrochemical parameters were estimated, indicating that the system has good and stable electron transfer properties. Moreover, horseradish peroxidase (HRP) was immobilized on the riboflavin-nafion functional membrane. The electrochemical behaviour of HRP was quasi-reversible with a formal potential of 80 +/- 5 mV (vs Ag/AgCl). The HRP in the film exhibited good catalytic activity towards the reduction of H2O2. It shows a linear dependence of its cathodic peak current on the concentration of H2O2, ranging from 10 to 300 (micro)M.

Intranasal immunization of mice with VP2 DNA of human rotavirus a induces cellular and humoral immunity.

DNA vaccination using a plasmid encoding Human rotavirus A (HuRV-A) inner capsid VP2 was examined in a mouse model. BALB/c mice were immunized intranasally (i.n.) with a VP2 DNA vaccine that induced cellular and humoral immune response to HuRV-A. The increased levels of cytokines IFN-gamma and IL-4 and the production of anti-VP2 IgG antibodies were detected. In addition, splenocyte proliferation detected by MTT test was enhanced in the mice treated with the vaccine. These results may encourage the development of a HuRV-A DNA vaccine derived from the inner layer of viral capsid that can be administered i.n.

Tools for the Measurement of Psychological Aspects of Organ Donation among the Families of Brain-dead People.

BACKGROUND: According to the basic ethical principle of non-maleficence, organ procurement systems need to be accountable to donor families. As organ donation can be potentially traumatic, donor families are at risk of developing psychological damage. Appropriate measurement tools are needed to diagnose such disorders and develop appropriate treatment measures. OBJECTIVE: To examine the appropriateness of measurement tools and approaches used in previous studies for assessing donor families' psychological well-being. METHODS: A structured online search was conducted in electronic databases namely ScienceDirect, PubMed, ProQuest, Scopus, Ovid, and Web of Science. The main inclusion criterion was the use of psychological assessment tools for data collection. RESULTS: 10 studies were included in which different tools had been used for measuring donor families' psychological well-being in the following 5 dimensions: stress, depression, grief, general health, and positive legacy of trauma. The major pitfalls of the reviewed studies were failure to specifically assess complicated grief and differentiating it from other psychological disorders, diversity of the tools used for psychological well-being assessment, and lack of clear definitions of donor families' psychological well-being and its dimensions. CONCLUSION: Donor families' psychological well-being is a complex and multidimensional concept and the existing measurement tools cannot accurately assess it. Therefore, the concept needs to be clearly explored and defined. Developing a comprehensive measurement tool or a set of scales is necessary for the early diagnosis of any impairment in donor families' psychological well-being.

Effect of silibinin and trans-chalcone in an Alzheimer's disease-like model generated by insulin amyloids

Amyloid fibrils are characteristic of several disorders including Alzheimer's disease (AD), with no cure or preventive therapy. Diminishing amyloid deposits using aromatic compounds is an interesting approach toward AD treatment. The present study examined the anti-fibrillogenic effects of silibinin and trans-chalcone in vitro, in vivo, and in silico on insulin amyloids. In vitro incubation of insulin at 37°C for 24 h induced amyloid formation. Addition of trans-chalcone and silibinin to insulin led to reduced amounts of fibrils as shown by thioflavin S fluorescence and Congo red absorption spectroscopy, with a better effect observed for silibinin. In vivo bilateral injection of fibrils formed by incubation of insulin in the presence or absence of silibinin and trans-chalcone or insulin fibrils plus the compounds in rats' hippocampus was performed to obtain AD characteristics. Passive avoidance (PA) test showed that treatment with both compounds efficiently increased latency compared with the model group. Histological investigation of the hippocampus in the cornu ammonis (CA1) and dentate gyrus (DG) regions of the rat's brain stained with hematoxylin-eosin and thioflavin S showed an inhibitory effect on amyloid aggregation and markedly reduced amyloid plaques. In silico, a docking experiment on native and fibrillar forms of insulin provided an insight onto the possible binding site of the compounds. In conclusion, these small aromatic compounds are suggested to have a protective effect on AD.

Fibril formation of lysozyme upon interaction with sodium dodecyl sulfate at pH 9.2.

Fibril formation seems to be a general property of all proteins. Its occurrence in hen or human lysozyme depends on certain conditions, namely acidic pHs or the presence of some additives. This paper studies the interaction of lysozyme with sodium dodecyl sulfate (SDS) at pH 9.2, using UV-visible spectrophotometry, circular dichroism (CD) spectropolarimetry, electron microscopy (EM) and chemometry. Based on observations such as the strange increase in absorbance at 650nm (pH 9.2) and the presence of intermediates, it is assumed that lysozyme fibrils have been formed at pH 9.2 in the presence of SDS as an anionic surfactant. Thioflavin T emission fluorescence and an EM image confirmed this assumption. beta-cyclodextrin was then used as a turbidity inhibitor to establish its effect on the distribution of intermediates that participate in fibril formation.

Expression and characterization of VP2 protein of human rotavirus a in a mammalian lung cell line.

A system for the expression and characterization of VP2 protein of Human rotavirus A, strain G3 was established in the mammalian lung cell line (A549). Expression of the recombinant VP2 (rVP2) protein was detected 48-72 hrs after transfection by Western blotting. The rVP2 protein expressed in A549 cells formed intracellular core-like particles (CLPs) 30 nm in diameter detected by electron microscopy (EM). These results showed that the A549 cells are suitable as efficient eukaryotic host for production of rVP2 protein.

Environment effect on spectral and charge distribution characteristics of some drugs of folate derivatives.

Molecular surrounding media as an important factor can effect on the operation of wide variety of drugs. For more study in this paper, spectral properties of Methotrexate and Folinic acid have been studied in various solvents. Our results show that the photo-physical of solute molecules depend strongly on solute-solvent interactions and active groups in their chemical structures. In order to investigate the contribution of specific and nonspecific interactions on the various properties of drug molecules, the linear solvation energy relationships concept is used. Moreover, charge distribution characteristics of used samples with various resonance structures in solvent environments were calculated by means of solvatochromic method. The high value of dipole moments in excited state show that local intramolecular charge transfer can occur by excitation. These results about molecular interactions can be extended to biological systems and can indicate completely the behaviors of Methotrexate and Folinic acid in polar solvents such as water in body system.

Morphological study of the role of calcium in the assembly of the rotavirus outer capsid protein VP7.

Maturation of rotavirus occurs in the endoplasmic reticulum (ER), a site of intracellular calcium storage. It was demonstrated previously that calcium plays an important role in the maturation of bovine rotavirus. We used protein A colloidal gold conjugated to an antibody to localize VP7, the outer capsid protein of the simian rotavius SA11, in permeabilized infected cells in the presence and absence of calcium in the culture medium. In medium containing calcium, VP7 was associated with nonenveloped double-shelled particles and membranous structures of the ER. In calcium-free medium, gold particles were not associated with the ER or with virus particles. Gold particles were distributed through the cytoplasm and were mainly associated with granular structures, but did not assemble onto virus particles. Our data suggest that in calcium-free medium, VP7 is synthesized, but does not remain incorporated, in the ER.

Photo-physical behavior of some antitumor anthracycline in solvent media with different polarity.

Absorption and emission spectra of three antitumour anthracyclines, with various substituent and stereoisomer groups, were studied in different solvents. The solute's photo-physical behavior strongly depends on solvent-solute interactions and solvent's nature. Solvatochromic method was used to investigate dipole moments of these materials in ground and excited states. Spectral variations were analyzed via means of linear solvation energy relationships concept, proposed by Kamlet and Taft. The results explain the nature of specific and non-specific solvent-solute interactions and functional groups' reorientation of studied anthracyclines in different media.

Effects of N and K applications on agronomic characteristics of two Iranian and landrace rice (Oryza sativa L.) cultivars.

Nutrition elements like nitrogen and potassium are restricting yield performance of rice cultivars and affecting on their characteristics. In order to consider effects of different amount of nitrogen and potassium on yield and chemical compounds of two rice cultivars (Tarrom and Neda which are landrace and improved Iranian genotypes, respectively), current experiment has been undertaken in 2004 and 2005. Four levels of nitrogen fertilizer (0, 50, 100 and 150 kg N ha(-1) from urea source) and four levels of potassium fertilizer (0, 75, 150 and 225 kg K2O ha(-1) from potassium sulfate source) have been applied in a split-factorial based on randomized block design with three replications. Nitrogen fertilizer has been applied in three different stages of plant growth (1/3 in transplanting, 1/3 in tillering and 1/3 in flowering initial stages) and potassium fertilizer has also been applied in two growth stages (1/2 in transplanting and 1/2 in shooting stages). Results indicated that application of nitrogen has increased plant height, number of tiller, length and width of flag leaf, length of panicle, number of grain per panicle, grain yield, amount of dry matter, biological yield, harvest index, leaf potassium, leaf nitrogen, 1000 grain weight and reducing percentage of hallow grain. Also, applied potassium has positive effects on all of above mentioned yield components except harvest index and 1000 grain yield. Neda cultivar was better than Tarrom genotype for most of the measured traits. Interaction of nitrogen and potassium were affected significantly on number of tiller per plant, grain yield, amount of dry matter and biological yield in Neda cultivar and on length of flag leaf, number of grain per panicle, grain yield, amount of dry matter, biological yield, harvest index and 1000 grain yield in Tarrom genotype.