Laser Doppler spectroscopy as applied to electrophoresis in protein solutions

The application of Laser Doppler spectroscopy (LDS) to the electrophoretic migration of macromolecules in solution by heterodyne light beating technique, previously developed by Ware and Flygare, has been improved by the design of a new microelectrophoresis cell and a high resolution in the frequency power spectrum. A 1024-channel correlator was used in combination with a software-controlled Fast Fourier transformation (FFT).This technique has been applied to single protein solution, bovine serum albumin (BSA), and to multicomponent systems, in particular to human blood serum. In comparison to normal free electrophoresis, LDS is more convenient and reveals more information in a much shorter period of time.     

Synthesis,characterization and biological aspects of novel five-coordinated dimeric-Cu(II) systems

The structural and spectroscopic properties of novel five-coordinated dimeric-Cu(II) system have been investigated. The biocidal activities of all eight compounds, ligands, cupric nitrate and standard drugs against six bacteria and three fungi were determined. The DNA interaction activity of complexes was studied using spectrophotometry and electrophoresis. The superoxide dismutase (SOD)-like activity of the complexes was compared with previously reported monomeric- and dimeric copper complexes. The results support the five-coordinated dimeric square pyramidal geometry for the quinolone-Cu(II) system.     

Insulin-Like Growth Factor I Receptor Binding in Brains of Alzheimer''s and Alcoholic Patients

Patients with chronic alcoholism and/or Alzheimer's disease show degenerative changes in the cerebral cortex and hippocampus. To investigate possible changes in insulin-like growth factor I receptor binding sites in brain tissue of patients with these pathological conditions, the number of 125I-insulin-like growth factor I binding sites was determined in tissues obtained from control patients and those with Alzheimer's and/or with a history of alcoholism. The four experimental groups examined consisted of patients from similar age groups. Postmortem histology and a clinical history were used for the diagnosis of Alzheimer's disease and alcoholism, respectively. Careful clinical records were kept concerning other variables such as immediate cause of death and medications administered before death. Specific binding of 125I-insulin-like growth factor I to homogenates prepared from cerebral cortex of Alzheimer's, alcoholic, alcoholic Alzheimer's, and age-matched control patients was similar, although Alzheimer's patients tended to have slightly higher binding values. No significant differences in insulin-like growth factor I binding in cerebral cortex were found with regard to age of patients, the interval between death and autopsy, and CNS-active medications. No statistical differences in 125I-insulin-like growth factor I binding were noted in hippocampal tissue from the four patient groups. Thus, human insulin-like growth factor I binding sites in cerebral cortex and hippocampus appear unaffected by several variables.     

Production of thermostable β-amylase and pullulanase by Clostridium thermosulfurogenes SV2 in solid-state fermentation: Screening of nutrients using Plackett-Burman design

Screening of fifteen nutrients belonging to four categories, viz., carbon, nitrogen, salt and complex organic sources was carried out using Plackett-Burman design for the production of thermostable #-amylase and pullulanase by Clostridium thermosulfurogenes SV2 in solid-state fermentation (SSF). This design involves screening of up to `nу' variables in just `n' number of experiments. Regression co-efficients and t-values were calculated by subjecting the experimental data to statistical analysis. Lactose, diammonium hydrogen phosphate, calcium chloride and casein hydrolysate showed higher regression co-efficients in the biomass formation. Among the fifteen nutrients screened, based on their performance in terms of product promoting ability, availability and cost, magnesium chloride, potato starch, ferrous sulphate, pearl millet flour and corn steep liquor were identified as most effective and, therefore, selected for inclusion in further optimization studies.     

Artonin E Induces Apoptosis via Mitochondrial Dysregulation in SKOV-3 Ovarian Cancer Cells

Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC₅₀ values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC₅₀ value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways.     

Selection of flowering forbs for conserving natural enemies in rice fields

The diversity of natural enemies harboured by flowering forbs on rice field bunds was recorded. Ageratum conozoides with a maximum Shannon diversity index of 1.8 followed by Acmella uliginosa, Eclipta alba and Tridax procumbens are amenable for ecological engineering, providing nectar, pollen and alternate prey to natural enemies.     

EhCoactosin Stabilizes Actin Filaments in the Protist Parasite Entamoeba histolytica

Entamoeba histolytica is a protist parasite that is the causative agent of amoebiasis, and is a highly motile organism. The motility is essential for its survival and pathogenesis, and a dynamic actin cytoskeleton is required for this process. EhCoactosin, an actin-binding protein of the ADF/cofilin family, participates in actin dynamics, and here we report our studies of this protein using both structural and functional approaches. The X-ray crystal structure of EhCoactosin resembles that of human coactosin-like protein, with major differences in the distribution of surface charges and the orientation of terminal regions. According to in vitro binding assays, full-length EhCoactosin binds both F- and G-actin. Instead of acting to depolymerize or severe F-actin, EhCoactosin directly stabilizes the polymer. When EhCoactosin was visualized in E. histolytica cells using either confocal imaging or total internal reflectance microscopy, it was found to colocalize with F-actin at phagocytic cups. Over-expression of this protein stabilized F-actin and inhibited the phagocytic process. EhCoactosin appears to be an unusual type of coactosin involved in E. histolytica actin dynamics.     

Near- and Far-Field Plasmonic Properties of Different Types of Eccentric Core-Shell Nanodimers

Finite element method (FEM) simulations have been carried out on free-standing and finite dielectric substrate-supported eccentric (i) silica core-gold nanoshell dimers and (ii) gold core-silica nanoshell dimers for understanding their near- and far-field plasmonic properties. In the case of eccentric silica core-gold nanoshell dimers, multiple peaks are observed in the near- and far-field spectra due to the plasmon hybridization. The number of peaks is found to be sensitive to the core offset parameters of the nanoshells forming nanodimer. The wavelength locations of the peaks due to the constructive coupling of the lower order modes found relatively more sensitive to the dielectric substrate. The number of peaks in the near- and far-field spectra found the same presence and absence of the dielectric substrate. The values of full width at half maximum (FWHM) of the peaks observed in the near-field spectra are found larger as compared to those observed in the far-field spectra. In contrast, in the case of eccentric gold core-silica nanoshell dimers, multiple peaks have not been observed. The FWHM of the observed peak is found sensitive to the core offset parameters of the nanoshells, and the number of peaks in the near field- and far-field spectra found not same in the presence and absence of the dielectric substrate. Moreover, the differences in near- and far-field spectra of plasmonically coupled (i) concentric nanoshells, (ii) eccentric nanoshells, and (iii) concentric and eccentric nanoshells also investigated numerically.