Insecticidal potential of natural zeolite and diatomaceous earth formulations against rice weevil (Coleoptera: Curculionidae) and red flour beetle (Coleoptera: Tenebrionidae)

Insecticidal potential of natural zeolites and diatomaceous earths originating from Serbia against Sitophilus oryzae (L.) and Tribolium castaneum (Herbst) was evaluated. Two natural zeolite formulations (NZ and NZ Modified) were applied to wheat at rates of 0.50, 0.75, and 1.0 g/kg, while two diatomaceous earth (DE) formulations (DE S-1 and DE S-2) were applied at rates of 0.25, 0.50, 0.75, and 1.0 g/kg. A bioassay was conducted under laboratory conditions: temperature of 24 +/- 1 degrees C, relative humidity in the range 50-55%, in tests with natural zeolites, and 60-65%, in tests with DEs, and in all combinations for progeny production. Mortality was assessed after 7, 14, and 21 d of insect contact with treated wheat, and the total mortality after an additional 7-d recovery on untreated broken wheat. Progeny production was also assessed after 8 wk for S. oryzae and 12 wk for T. castaneum. The highest mortality for S. oryzae and T. castaneum was found after the longest exposure period and 7 d of recovery, on wheat treated with NZ at the highest rate and DEs at rates of 0.50 -1.0 g/kg. Progeny reduction higher than 90% was achieved after 14 and 21 d of contact of both beetle pests with wheat treated with DE S-1 at 0.50-1.0 g/kg and DE S-2 at 0.75-1.0 g/kg, while the same level of reduction was achieved only for T. castaneum after its contact with the highest rate of NZ formulation. NZ Modified, applied even at the highest rate, revealed much lower insecticidal potential.     

Continuum simulations of acetylcholine diffusion with reaction-determined boundaries in neuromuscular junction models

The reaction-diffusion system of the neuromuscular junction has been modeled in 3D using the finite element package FEtk. The numerical solution of the dynamics of acetylcholine with the detailed reaction processes of acetylcholinesterases and nicotinic acetylcholine receptors has been discussed with the reaction-determined boundary conditions. The simulation results describe the detailed acetylcholine hydrolysis process, and reveal the time-dependent interconversion of the closed and open states of the acetylcholine receptors as well as the percentages of unliganded/monoliganded/diliganded states during the neuro-transmission. The finite element method has demonstrated its flexibility and robustness in modeling large biological systems.     

Temporal and regional changes of superoxide dismutase and glutathione peroxidase activities in rats exposed to focal cerebral ischemia

Reactive oxygen species are important cause of tissue injury during cerebral ischemia and reperfusion (I/R). Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) are intracellular enzymes responsible for endogenous antioxidant defense of tissues affected by I/R. The aim of this study was to examine temporal and regional changes of SOD and GSH-Px activities in animals exposed to transient focal cerebral ischemia. Male Wistar Hannover rats were subjected to the right middle cerebral artery occlusion for 2?h. The animals were sacrificed immediately, 0·5, 1, 2, 3, 6, 24, 48, 72 or 168?h after ischemic procedure. SOD and GSH-Px activities were determined spectrophotometrically in the hippocampus and parietal cortex, both unilaterally and contralaterally to the occlusion. Sham-operated animals were used as the control group. Our results indicated that transient focal cerebral ischemia causes significant changes in SOD activities in the hippocampus and parietal cortex such as in GSH-Px activities in the parietal cortex, unilaterally and contralaterally to the lesion in rats during different reperfusion periods. Statistically significant activation of GSH-Px was registered neither in the right nor in the left hippocampus of ischemic animals. Copyright ? 2012 John Wiley & Sons, Ltd.     

Atherosclerotic lesions of supra-aortic arteries in diabetic patients

The aim of this prospective study was to determine the prevalence and localization of stenotic atherosclerotic lesions of supra-aortic arteries in diabetic patients according to age and sex. Angiograms obtained by digital subtraction angiography were analyzed in 150 diabetic patients (study group) and 150 non-diabetic patients (control group) with symptoms of cerebral ischemia. Diabetic patients were found to have a significantly higher prevalence of stenotic atherosclerotic lesions of the internal carotid artery. Lesions of the large supra-aortic arteries were significantly more common in the left than in the right side of the neck (p < 0.001), but the difference between the diabetic and the non-diabetic group did not reach statistical significance. Hemodynamic conditions were found to be more important than diabetes for the occurrence of atherosclerotic lesions in these arteries. Changes in the proximal segment of the left common carotid artery were the most common finding in diabetic patients, hence attention should be paid to this localization on control examinations.     

Comparative research on substance abuse and self-perception among adolescents with physical handicap

The research on substance (alcohol, tobacco and drug) abuse and on self-perception was done by comparing a test group of physically disabled adolescents and a test group of non-disabled adolescents. The respondents of the experimental group were students of the only special high school for physically handicapped persons in Croatia, Zagreb. The respondents of the control group were the students of two regular high schools in the capital of Croatia. The instrument used in this research was a self-reported, anonymous questionnaire. The respondents completed the questionnaire in the classroom. The data analysis regarding alcohol abuse indicated that physically disabled adolescents drink more often and out of quite different motives than their non-disabled peers. Regarding the prevalence, frequency, quantity and motives for smoking, no statistically significant difference has been found between the tested groups. On the contrary, significant differences between handicapped and non-disabled adolescents were evident regarding drug abuse. Only one physically disabled examinee used a drug--marijuana, only a few times a year. On the other hand, almost one quarter of the non-disabled adolescents use at least one, five at the most, type of drug sometimes or often. The results on the self-perception scale show that adolescent with physical disabilities have a much more negative attitude toward themselves than non-disabled controls. Their self-esteem and self-confidence are seriously diminished. Described findings could have a mighty impact on ways of preventing substance abuse, and on ways of increasing self-esteem among disabled and non-disabled adolescents.     

Dual targeting of organellar seryl-tRNA synthetase to maize mitochondria and chloroplasts

Aminoacyl-tRNA synthetases (AARSs) play a critical role in translation and are thus required in three plant protein-synthesizing compartments: cytosol, mitochondria and plastids. A systematic study had previously shown extensive sharing of organellar AARSs from Arabidopsis thaliana, mostly between mitochondria and chloroplasts. However, distribution of AARSs from monocot species, such as maize, has never been experimentally investigated. Here we demonstrate dual targeting of maize seryl-tRNA synthetase, SerZMo, into both mitochondria and chloroplasts using combination of complementary methods, including in vitro import assay, transient expression analysis of green fluorescent protein (GFP) fusions and immunodetection. We also show that SerZMo dual localization is established by the virtue of an ambiguous targeting peptide. Full-length SerZMo protein fused to GFP is targeted to chloroplast stromules, indicating that SerZMo protein performs its function in plastid stroma. The deletion mutant lacking N-terminal region of the ambiguous SerZMo targeting peptide was neither targeted into mitochondria nor chloroplasts, indicating the importance of this region in both mitochondrial and chloroplastic import.     

Expression of one sponge Iroquois homeobox gene in primmorphs from Suberites domuncula during canal formation

Sponges (Porifera) represent the evolutionary oldest multicellular animals. They are provided with the basic molecules involved in cell-cell and cell-matrix interactions. We report here the isolation and characterization of a complementary DNA from the sponge Suberites domuncula coding for the sponge homeobox gene, SUBDOIRX-a. The deduced polypeptide with a predicted Mr of 44,375 possesses the highly conserved Iroquois-homeodomain. We applied in situ hybridization to localize Iroquois in the sponge. The expression of this gene is highest in cells adjacent to the canals of the sponge in the medulla region. To study the expression of Iroquois during development, the in vitro primmorph system from S. domuncula was used. During the formation of these three-dimensional aggregates composed of proliferating cells, the expression of Iroquois depends on ferric iron and water current. An increased expression in response to water current is paralleled with the formation of canal-like pores in the primmorphs. It is suggested that Iroquois expression is involved in the formation of the aquiferous system, the canals in sponges and the canal-like structures in primmorphs.     

Non-equilibrium allele frequency spectra via spectral methods

A major challenge in the analysis of population genomics data consists of isolating signatures of natural selection from background noise caused by random drift and gene flow. Analyses of massive amounts of data from many related populations require high-performance algorithms to determine the likelihood of different demographic scenarios that could have shaped the observed neutral single nucleotide polymorphism (SNP) allele frequency spectrum. In many areas of applied mathematics, Fourier Transforms and Spectral Methods are firmly established tools to analyze spectra of signals and model their dynamics as solutions of certain Partial Differential Equations (PDEs). When spectral methods are applicable, they have excellent error properties and are the fastest possible in high dimension; see Press et al. (2007). In this paper we present an explicit numerical solution, using spectral methods, to the forward Kolmogorov equations for a Wright–Fisher process with migration of K populations, influx of mutations, and multiple population splitting events.     

Compartmentalization of the splicing machinery in plant cell nuclei

The cell nucleus is a membrane-surrounded organelle that contains numerous compartments in addition to chromatin. Compartmentalization of the nucleus is now accepted as an important feature for the organization of nuclear processes and for gene expression. Recent studies on nuclear organization of splicing factors in plant cells provide insights into the compartmentalization of the plant cell nuclei and conservation of nuclear compartments between plants and metazoans.     

A study on the genotoxic effects of 8-Cl-cAMP on human lymphocytes in vitro

8-chloro-cyclic adenosine 3',5'-monophosphate (8-Cl-cAMP) is the most potent cAMP analogue that selectively inhibits a variety of cancer cell lines in vitro and tumors in vivo. Its action toward a variety of tumors, especially when coupled with other antitumor agents, have lead to phase I clinical investigations and recently phase II clinical investigations. Until today very little was done to evaluate its genotoxic potential. In order to evaluate its genotoxic potential we used the cytogenetic and cytokinesis block micronucleus assay in vitro on peripheral blood lymphocytes of healthy individuals. Using three concentrations (1 microM, 5 microM and 15 microM), 8-Cl-cAMP in normal human peripheral blood lymphocytes did not induce any cytogenetic aberrations of the structural type [chromatid breakage, isochromatid breakage and gaps], but did induce premature centromere separation (PCS) in all respective doses and increased the frequency of micronuclei (p <0.05) only in the highest dose (15 microM). Antiproliferative action of 8-Cl-cAMP was estimated by using the cytokinesis block nuclear division index (NDI). The results showed a decrease in the NDI of cells exposed to all doses of 8-Cl-cAMP when compared to control. Therefore, the overall results show a genotoxic potential of 8-Cl-cAMP in peripheral blood lymphocytes in vitro.