Effect of the lavage of the digestive tract on microflora in patients with polyps in the large intestine

The microbial status of the intestine and the influence of lavage with polyethylene glycol and balanced electrolyte solution (PEG + E), used in the process of the preparation of patients to polypectomy, on this status were evaluated. The study of microflora was made before oral lavage after, and 48-72 hours later its completion. For control, a group of healthy volunteers, also subjected to oral lavage with PEG + E, was used. The lavage of the digestive tract with PEG + E led to a sharp change in the microbial status in both groups. Some microorganisms, previously absent in the intestine, were found after lavage. The processes of the restoration of intestinal microflora after lavage in healthy volunteers and in patients with polyps had certain differences. In healthy volunteers intestinal microflora was completely restored, and even improved, 48-72 hours after lavage with PEG + E, while at the expiration of this time intestinal microflora in the patients with polyps could be characterized as dysbiotic.     

The LIS1-related NUDF protein of Aspergillus nidulans interacts with the coiled-coil domain of the NUDE/RO11 protein

The nudF gene of the filamentous fungus Aspergillus nidulans acts in the cytoplasmic dynein/dynactin pathway and is required for distribution of nuclei. NUDF protein, the product of the nudF gene, displays 42% sequence identity with the human protein LIS1 required for neuronal migration. Haploinsufficiency of the LIS1 gene causes a malformation of the human brain known as lissencephaly. We screened for multicopy suppressors of a mutation in the nudF gene. The product of the nudE gene isolated in the screen, NUDE, is a homologue of the nuclear distribution protein RO11 of Neurospora crassa. The highly conserved NH(2)-terminal coiled-coil domain of the NUDE protein suffices for protein function when overexpressed. A similar coiled-coil domain is present in several putative human proteins and in the mitotic phosphoprotein 43 (MP43) of X. laevis. NUDF protein interacts with the Aspergillus NUDE coiled-coil in a yeast two-hybrid system, while human LIS1 interacts with the human homologue of the NUDE/RO11 coiled-coil and also the Xenopus MP43 coiled-coil. In addition, NUDF coprecipitates with an epitope-tagged NUDE. The fact that NUDF and LIS1 interact with the same protein domain strengthens the notion that these two proteins are functionally related.     

The specific blocks of heterochromatin on metaphase chromosomes of horse and Prjewalski horse detected by in situ digestion with restriction endonucleases

Restriction endonuclease in situ digestion of metaphase chromosomes gives an opportunity to reveal strips with different structure within GC-rich pericentric heterochromatin of the domestic horse and the wild Przewalski horse. Blocks of heterochromatin, which are insensitive to HaeIII and brightly stained with chromomycin A3 after restriction enzyme digestion, are localized on the border with euchromatin in the majority of chromosomes of Equus caballus and E. przewalskii. In contrast to chromosome 5 of E. caballus, acrocentric chromosomes of E. prezewalskii which are homologous to this chromosome have RE-CMA-blocks. We discuss a possible nature of the specific heterochromatin, which is insensitive to restriction enzyme digestion, and its role in the karyotype evolution.     

Dermatoglyphics of the nganasans and the forest entsy from the Taimir Peninsula

Dermatoglyphic data on 17 traits (digital arches, ulnar loops, whorls, patterns on the hypothenar and thenar/I,II,III, and IV interdigital areas, main line C absence and its incompleteness, mean digital ridge-count, a–b, b–c, and c–d ridge–counts, atd angle, pattern intensity index, and main line index) are presented in this paper for 194 males and 224 females from the Taimir Peninsula. Also presented is a population analysis of the Taimir aborigines based on quantitative traits, and comparisons of this population with some Siberian and North American populations.     

Long irregular regions in proteins as combinations of small standard structures

The structure of long loop regions in proteins is considered. It is shown that long loops can be represented as combinations of small standard structures described in our previous papers. Relationship between the structures and the amino acid sequences of the loop regions is discussed.     

Intraspecies Genomic Diversity and Long-Term Persistence of Bifidobacterium longum

Members of genus Bifidobacterium are Gram-positive bacteria, representing a large part of the human infant microbiota and moderately common in adults. However, our knowledge about their diversity, intraspecific phylogeny and long-term persistence in humans is still limited. Bifidobacterium longum is generally considered to be the most common and prevalent species in the intestinal microbiota. In this work we studied whole genome sequences of 28 strains of B. longum, including 8 sequences described in this paper. Part of these strains were isolated from healthy children during a long observation period (up to 10 years between isolation from the same patient). The three known subspecies (longum, infantis and suis) could be clearly divided using sequence-based phylogenetic methods, gene content and the average nucleotide identity. The profiles of glycoside hydrolase genes reflected the different ecological specializations of these three subspecies. The high impact of horizontal gene transfer on genomic diversity was observed, which is possibly due to a large number of prophages and rapidly spreading plasmids. The pan-genome characteristics of the subspecies longum corresponded to the open pan-genome model. While the major part of the strain-specific genetic loci represented transposons and phage-derived regions, a large number of cell envelope synthesis genes were also observed within this category, representing high variability of cell surface molecules. We observed the cases of isolation of high genetically similar strains of B. longum from the same patients after long periods of time, however, we didn’t succeed in the isolation of genetically identical bacteria: a fact, reflecting the high plasticity of microbiota in children.     

DNA mimics on the base of pyrrolidine and hydroxyproline

In order to improve physicochemical and biological properties of natural oligonucleotides in particular increasing their affinity for nucleic acids, the selectivity of action and biological sustainability, several types of DNA mimics were designed. The survey collected data on the synthesis and properties of the DNA mimics - peptide-nucleic acids analogues, which are derivatives of pyrrolidine and hydroxyproline. We examine some physicochemical and biological properties of negatively charged mimics of this type, containing phosphonate residues, and possessing a high affinity for DNA and RNA, selective binding with nucleic acids and stability in various biological systems. Examples of the use of these mimics as tools for molecular biological research, particularly in functional genomics are given. The prospects for their use in diagnostics and medicine are discussed.     

N-azidomethylbenzoyl blocking group in the phosphotriester synthesis of oligonucleotides

An effective modification of phosphotriester method for automatic synthesis of DNA and RNA fragments using O-nucleophilic intramolecular catalysis and 2-(azidometil)benzoyl group to protect amino groups of heterocyclic bases of nucleotides is described.