The determination of hepatitis A antibodies in epidemiological practice

Epidemiological analysis of hepatitis A morbidity in a city with the population of 500,000 persons in 1960-1987 was carried out. Three periods of morbidity rises among children aged 3-6 years and 7-14 years and living at the same areas (microdistricts) were established. Blood sera from healthy children were tested for the presence of antibodies to hepatitis A in enzyme immunoassay. The data on the sanitary and bacteriological study of tap water were analyzed. Unsatisfactory results of water analysis in different microdistricts correlated with the presence of antibodies in the population of these microregions and with the average morbidity indices for many years.     

Evaluation of the radioprotective effect of total gaseous hypoxia based on the criteria of delayed radiation damage

Breathing with gas mixture containing 6-8% of oxygen during whole-body and large-field irradiation of mice diminishes the radiation-induced life-span shortening (DMF = 2.2) and decreases the degree of canescence (DMF = 1.5), the frequency and severity of nephro- and cardiosclerosis (DMF = 1.5), and the probability of occurrence of pleura and pericardium edemas provoked by cardiopulmonary insufficiency (DMF = 1.4). The fact that hypoxic hypoxia retains its high radioprotective efficiency in relation to the delayed effects of radiation is important for radiotherapy of tumors.     

Haemophilus influenzae antibiotic resistant strains isolated in Moscow in 2002-2004]

The results of 3-year observation on emergence of H. influenzae antibiotic resistant strains in Moscow are summarized. The study included 566 strains isolated from patients in 2002-2004. The susceptibility was determined by the 2-fold microdilution method on the Haemophilus test medium. The percentage of the resistant strains isolated in 2002, 2003 and 2004 was the following: ampicillin --4.9, 3.2 and 3.6%, tetracycline--3.3, 3.2 and 1.8% and co-trimoxazole--10.9, 20.9 and 20% respectively. The strains isolated in 2003 and 2004 were resistant to azithromycin in 0.6 and 1.8% of the isolates and to clarithromycin in 1.3 and 3.2% of the isolates respectively. Five isolates differed by the minimum resistance to ampicillin whereas producing no beta-lactamase (BLNAR strains). The drugs of choice for the treatment of respiratory tract infections mainly due to H. influenzae, i.e. acute otitis and sinusitis, chronic bronchitis exacerbation and sometimes pneumonia remain betalactam antibiotics. From the microbiological viewpoint the inhibitor-protected aminopenicillins, cefuroxime and cefotaxime have no significant advantages vs. amoxycillin. The use of cotrimoxazole and chloramphenicol should be considered inexpedient.     

Role of the cholinergic system in the dorsal and ventral striatum of the brain in regulation of a learned movement in rats

Administration of carbachol into the rat brain ventral striatum increased the number of movements with prolonged extension and decreased the number of short not reinforced movements, whereas the same administration into the dorsal striatum deteriorated slow movements. Scopolamine administration, irrespective of the site, increased the number of fast not reinforced movements. The findings suggest that cholinergic system of the rat ventral striatum is involved in the maintenance of the rat forepaw muscle tone.     

Mapping the amino acid properties of constituent nucleoporins onto the yeast nuclear pore complex

Visualization of molecular structures aids in the understanding of structural and functional roles of biological macromolecules. Macromolecular transport between the cell nucleus and cytoplasm is facilitated by the nuclear pore complex (NPC). The ring structure of the NPC is large and contains several distinct proteins (nucleoporins) which function as a selective gate for the passage of certain molecules into and out of the nucleus. In this note we demonstrate the utility of a python code that allows direct mapping of the physiochemical properties of the constituent nucleoporins on the scaffold of the yeast NPC׳s cytoplasmic view. We expect this tool to be useful for researchers to visualize the NPC based on their physiochemical properties and how it alters when specific mutations are introduced in one or more of the nucleoporins. The code developed using Python is available freely from the authors.     

Prediction of the three-dimensional structure of aflatoxin of Aspergillus flavus by homology modelling

Aflatoxins are polyketide-derived secondary metabolites produced by Aspergillus spp. The toxic effects of aflatoxins have adverse consequences for human health and agricultural economics. The aflR gene, a regulatory gene for aflatoxin biosynthesis, encodes a protein containing a zinc-finger DNA-binding motif. AFLR-Protein three-dimensional model was generated using Robetta server. The modeled AFLR-Protein was further optimization and validation using Rampage. In the simulations, we monitored the backbone atoms and the C-α-helix of the modeled protein. The low RMSD and the simulation time indicate that, as expected, the 3D structural model of AFLR-protein represents a stable folding conformation. This study paves the way for generating computer molecular models for proteins whose crystal structures are not available and which would aid in detailed molecular mechanism of inhibition of aflatoxin.