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PubMedDate not supplied

[Planar charged clusters--structural invariants of the gamma-crystallin family of the crystalline lens: functional role and evolutionary conservatism].

Plane charge clusters from the calf eye lens protein gamma-crystallin are considered. The clusters consist of four to six side chain charged groups with interatomic distances in ionic pairs from 4 to 7 A. The charge clusters appear to decrease the hydrophilic potential of the molecular surface which maintains the transparent refracting lens medium of vertebrates with a very high protein concentration. It is shown that the charge pattern for different gene products of one species is conservative as well as for whole set of 25 sequences of vertebrates, including carp, frog, mouse, rat, calf and human. Taking into account "neutral mutations", Asp-Glu and Arg-Lys the homology of those charge positions is equal to 95-100%. Functionally important charge clusters are absent in the ancient structural motifs of gamma-crystallin.

Amino Acid Sequence↗
PubMedDate not supplied

Thoracoscopic management of thoracic duct injury: Is there a place for conservatism?

Thoracic duct injury is a rare but serious complication following chest surgeries and major neck dissections. Clinically, it can present as cervical chylous fistula, chylothorax or chylopericardium. Without treatment, the mortality is up to 50% and thus, early aggressive therapy is indicated. Traditional conservative management includes low-fat diet, parenteral nutrition, careful monitoring of fluid and electrolytes, and drainage of the neck wound or chylothorax. Patients with failed conservative management require definitive treatment in the form of ligation of the thoracic duct, which has traditionally been done by thoracotomy. The advent of Video-Assisted-Thoracoscopic-Surgery (VATS) over the last decade has changed the approach towards the management of numerous chest diseases. Thoracoscopic ligation of the thoracic duct has also been reported. We report herein a case of postoperative cervical chylous fistula managed successfully by VATS thoracic duct ligation and present a systematic analysis of the English literature to highlight the current trends in the management of thoracic duct injury.

Adult↗
PubMedDate not supplied

[Similarity of domain organization of proteins in phylogenetically distant organisms as a basis of meiosis conservatism].

The cytological mechanism of meiosis is very conservative in all eukaryotes. Some meiosis-specific structural proteins of yeasts, nematode Caenorhabditis elegans, Drosophila, and mammals, which play identical roles in cells during meiosis, do not have homology of the primary structure, but their domain organization and conformation are similar. The enzymes of meiotic recombination in yeasts and plants have similar epitopes. These facts suggest that the similarity of the higher level of organization of the meiosis-specific proteins allows these proteins to form similar subcellular structures and produce similar cytological picture of meiosis and similar functions of these subcellular structures. Finally, this leads to a conservative scheme of meiosis in evolutionally distant eukaryotes.

Animals↗
PubMedDate not supplied

[The role of the cognitive context in the conservatism of unconscious visual sets].

Rigidity of a verbal set was compared in three series of experiments: (1) pseudowords were presented at the set-forming stage and were changed for common words at the testing stage; (2) in the same conditions as in 1, an additional task of target localization in the matrix by two distinctive features was introduced; (3) in the additional target localization task, the spatial component was strengthened whereas image recognition component was reduced. The results confirmed our hypothesis about the context-dependence of the rigidity of the visual set. This characteristic substantially depends on a working memory loading and cognitive tasks performed by a subject, in particular, the relationship between the degrees of involvement of the ventral and dorsal visual systems into the cortical processing of sequential verbal and nonverbal visual stimuli. The experimental paradigm can serve as a model for the investigation of the roles of the ventral and dorsal visual systems in the recognition function.

Adult↗
PubMed2006

[Genome conservatism of phiKMV-like bacteriophages (T7 supergroup) active against Pseudomonas aeruginosa].

The T7-like phiKMV bacteriophage active on Pseudomonas aeruginosa was previously isolated by us and shown to have DNA resistant to many endonucleases. A loss of sensitive sites might be a consequence of a long phiKMV evolution on different hosts. To elucidate, whether this trait is shared by other similar phages, several new phiKMV-like phages were isolated from different sources and compared. All studied phiKMV-like phages formed three groups, insignificantly differing in the number and localization of endonuclease-sensitive DNA sites. This confirms that the present-day phages of this species have highly conserved genomes. Mutational "restoration" of the lost sites may be restricted by a lethal effect. The phiKMV-like phages were shown for the first time to increase the rate of in vitro accumulation of giant phiKZ-like phages of P. aeruginosa. This effect is characteristic only of phiKMV-like phages.

Bacteriophage Typing↗