Polycondensation of Silicon and Titanium Dioxide Precursors on Natural and Synthetic Polymeric Matrices

Russian Journal of Bioorganic Chemistry - In this report we examined the ability of some natural and synthetic polymers to serve as a catalyst and a template for the polycondensation of silicon and...     

Features of biosynthesis of chitinolytic enzymes by <Emphasis Type="Italic">Streptomyces griseus</Emphasis> var. <Emphasis Type="Italic">streptomycini</Emphasis>

The previously selected strain Streptomyces griseus var. streptomycini is able to hydrolyze colloid as well as crystal forms of chitin. During the submerged cultivation in the medium with crystal chitin, the chitinase activity achieved the maximal value after 46–50 h of culturing. Use of colloid chitin as an inductor allowed increasing the chitinolytic activity by 33%. Adding of mannose to the medium increased the chitinase activity of the producer by two times. It has been shown that the chitinase biosynthesis bears an inducible nature.     

An overview of malaria transmission from the perspective of Amazon Anopheles vectors

In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.     

Numerical modeling of molecular-motor-assisted transport of adenoviral vectors in a spherical cell

Viral gene delivery in a spherical cell is investigated numerically. The model of intracellular trafficking of adenoviruses is based on molecular-motor-assisted transport equations suggested by Smith and Simmons. These equations are presented in spherical coordinates and extended by accounting for the random component of motion of viral particles bound to filaments. This random component is associated with the stochastic nature of molecular motors responsible for locomotion of viral particles bound to filaments. The equations are solved numerically to simulate viral transport between the cell membrane and cell nucleus during initial stages of viral infection.     

Exploring the Gastrointestinal “Nemabiome”: Deep Amplicon Sequencing to Quantify the Species Composition of Parasitic Nematode Communities

Parasitic helminth infections have a considerable impact on global human health as well as animal welfare and production. Although co-infection with multiple parasite species within a host is common, there is a dearth of tools with which to study the composition of these complex parasite communities. Helminth species vary in their pathogenicity, epidemiology and drug sensitivity and the interactions that occur between co-infecting species and their hosts are poorly understood. We describe the first application of deep amplicon sequencing to study parasitic nematode communities as well as introduce the concept of the gastro-intestinal “nemabiome”. The approach is analogous to 16S rDNA deep sequencing used to explore microbial communities, but utilizes the nematode ITS-2 rDNA locus instead. Gastro-intestinal parasites of cattle were used to develop the concept, as this host has many well-defined gastro-intestinal nematode species that commonly occur as complex co-infections. Further, the availability of pure mono-parasite populations from experimentally infected cattle allowed us to prepare mock parasite communities to determine, and correct for, species representation biases in the sequence data. We demonstrate that, once these biases have been corrected, accurate relative quantitation of gastro-intestinal parasitic nematode communities in cattle fecal samples can be achieved. We have validated the accuracy of the method applied to field-samples by comparing the results of detailed morphological examination of L3 larvae populations with those of the sequencing assay. The results illustrate the insights that can be gained into the species composition of parasite communities, using grazing cattle in the mid-west USA as an example. However, both the technical approach and the concept of the ‘nemabiome’ have a wide range of potential applications in human and veterinary medicine. These include investigations of host-parasite and parasite-parasite interactions during co-infection, parasite epidemiology, parasite ecology and the response of parasite populations to both drug treatments and control programs.     

Structure based virtual screening of ligands to identify cysteinyl leukotriene receptor 1 antagonist

Montelukast and Zafirlukast are known leukotriene receptor antagonists prescribed in asthma treatment. However, these fall short as mono therapy and are frequently used in combination with inhaled glucocorticosteroids with or without long acting beta 2 agonists. Therefore, it is of interest to apply ligand and structure based virtual screening strategies to identify compounds akin to lead compounds Montelukast and Zafirlukast. Hence, compounds with structures having 95% similarity to these compounds were retrieved from NCBI׳s PubChem database. Compounds similar to lead were grouped and docked at the antagonist binding site of cysteinyl leukotriene receptor 1. This exercise identified compounds UNII 70RV86E50Q (Pub Cid 71587778) and Sure CN 9587085 (Pub Cid 19793614) with higher predicted binding compared to Montelukast and Zafirlukast. It is shown that the compound Sure CN 9587085 showed appreciable ligand receptor interaction compared to UNII 70RV86E50Q. Thus, the compound Sure CN 9587085 is selected as a potent antagonist to cysteinyl leukotriene receptor 1 for further consideration in vitro and in vivo validation.     

Morphology and ultrastructure of modern and fossil spores in order Schizaeales schimp

The morphology and ultrastructure of modern and fossil spores were investigated using light, scanning, and transmission electron microscopes. We grouped spores into two groups according to ultrastructural features and sculptures of sporoderm: 1—exospore of Anemia and Klukia form the echini of sculpture; 2—exospore of Lygodium is smooth and perispore forms sculpture.     

Biomimetic Synthesis of Nanosized Silica Structures on a Substrate with Silicatein

Using atomic force microscopy (AFM), the formation of nanosized silica structures on a substrate, catalyzed by the recombinant silicatein LoSilA1 from the marine sponge Latrunculia oparinae, was studied. It has been shown that at room temperature under neutral conditions, recombinant silicatein immobilized on a mica substrate causes the rapid polycondensation of tetrakis(2-hydroxyethyl) orthosilicate to form spherical particles. Thus, immobilized silicatein may acts as a catalyst in the preparation of ordered silica structures on various surfaces.     

Identification of structural DNA variations in human cell cultures after long-term passage

Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations.