Synergy between cationic lipid and co-lipid determines the macroscopic structure and transfection activity of lipoplexes

The large number of cytofectin and co-lipid combinations currently used for lipoplex-mediated gene delivery reflects the fact that the optimal cytofectin/co-lipid combination varies with the application. The effects of structural changes in both cytofectin and co-lipid were systematically examined to identify structure–activity relationships. Specifically, alkyl chain length, degree of unsaturation and the head group to which the alkyl side chain was attached were examined to determine their effect on lipoplex structure and biological activity. The macroscopic lipoplex structure was assessed using a dye-binding assay and the biological activity was examined using in vitro transfection in three diverse cell lines. Lipoplexes were formulated in three different vehicles currently in use for in vivo delivery of naked plasmid DNA (pDNA) and lipoplex formulations. The changes in dye accessibility were consistent with structural changes in the lipoplex, which correlated with alterations in the formulation. In contrast, transfection activity of different lipoplexes was cell type and vehicle dependent and did not correlate with dye accessibility. Overall, the results show a correlation between transfection and enhanced membrane fluidity in both the lipoplex and cellular membranes.     

Human temperament and choice preference between probability of the goal achievement and the goal value

The purpose of this work was to experimentally ascertain the relationships between human formal-dynamic properties (temperament) and characteristics of his/her motivation sphere associated with the choice of a profession. Thirty eight students of a sports institute (aged 19-28) took part in the study. The formal-dynamic properties were assessed with the help of Rusalov's Questionnaire. The motivation of the choice of profession was assessed with the help of the specially developed test questionnaire. Two main components of choice motivation were identified: the value of the profession and probability of mastering this profession. It was found that persons of sanguine temperament (with a higher capacity for work, mobile and quick) are oriented primarily to the value of profession, while persons of melancholic temperament to the probability of mastering this profession.     

A psychophysiological approach toward the problem of consciousness

Psychophysiological analysis of the relationship between the level of consciousness and the brain activation permitted an identification of three levels of consciousness at the transition from wakefulness to sleep. A change in the intensity and quality of involuntarily mental processes served as an index of the level of consciousness according to subjects' self-reports. It was found that a certain EEG profile corresponds to each level of consciousness under study. Data obtained showed that the lowest level of activation corresponds to a state in which a subject notes an inhibition of "internal speech", "failure of thoughts". At this case the dynamics of the EEG high frequency rhythm changes which is possibly related to the mechanism of transmission of cognitive information.     

Gene structure,transcripts and calciotropic effects of the PTH family of peptides in <Emphasis Type="Italic">Xenopus</Emphasis> and chicken

Background  

Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) belong to a family of endocrine factors that share a highly conserved N-terminal region (amino acids 1-34) and play key roles in calcium homeostasis, bone formation and skeletal development. Recently, PTH-like peptide (PTH-L) was identified in teleost fish raising questions about the evolution of these proteins. Although PTH and PTHrP have been intensively studied in mammals their function in other vertebrates is poorly documented. Amphibians and birds occupy unique phylogenetic positions, the former at the transition of aquatic to terrestrial life and the latter at the transition to homeothermy. Moreover, both organisms have characteristics indicative of a complex system in calcium regulation. This study investigated PTH family evolution in vertebrates with special emphasis on Xenopus and chicken.     

Unusual metastasis of papillary thyroid carcinoma to larynx and hypopharynx a case report

Background  

Although direct infiltration of papillary carcinoma of thyroid to larynx, trachea and esophagus is well recognized, lymphatic and vascular metastases to larynx and hypopharynx have rarely been reported.