Cytomorphological characteristics of dendritic cells

Five morphological degrees of maturity of dendritic cells induced from monocytes of peripheral blood in oncological patients have been revealed using originally prepared and stained cytological preparations. Cytological examination of dendritic cells can be used for their identification in production of dendritic cell antitumor vaccines.     

Impaired reproductive behavior by lack of GluR-B containing AMPA receptors but not of NMDA receptors in hypothalamic and septal neurons

The roles of ionotropic glutamate receptors in mammalian reproduction are unknown. We therefore generated mice lacking a major subtype of (S)-alpha-amino-3-hydroxy-5-methyl-isoxazolepropionic acid (AMPA) receptors or all N-methyl-d-aspartate (NMDA) receptors in GnRH neurons and other mainly limbic system neurons, primarily in hypothalamic and septal areas. Male mice without NMDA receptors in these neurons were not impaired in breeding and exhibited similar GnRH secretion as control littermates. However, male mice lacking GluR-B containing AMPA receptors in these neurons were poor breeders and severely impaired in reproductive behaviors such as aggression and mounting. Testis and sperm morphology, testis weight, and serum testosterone levels, as well as GnRH secretion, were unchanged. Contact with female cage bedding failed to elicit male sexual behavior in these mice, unlike in control male littermates. Their female counterparts had unchanged ovarian morphology, had bred successfully, and had normal litter sizes but exhibited pronounced impairments in maternal behaviors such as pup retrieval and maternal aggression. Our results suggest that NMDA receptors and GluR-B containing AMPA receptors are not essential for fertility, but that GluR-B containing AMPA receptors are essential for male and female reproduction-related behaviors, perhaps by mediating responses to pheromones or odorants.     

QM-polarized ligand docking accurately predicts the trend in binding affinity of a series of arylmethylene quinuclidine-like derivatives at the α4β2 and α3β4 nicotinic acetylcholine receptors (nAChRs)

Compounds containing a quinuclidine scaffold are promising drug candidates for pharmacological management of the central nervous system (CNS) pathologies implicating nAChRs. We have carried out binding affinity and in-silico docking studies of arylmethylene quinuclidine-like derivatives at the α4β2 receptor using in-vitro receptor binding assay and comparative modeling, respectively. We found that introducing a hydrogen-bond acceptor into the 3-benzylidene quinuclidine derivative resulted in a 266-fold increase in binding affinity and confers agonism properties. By contrast, addition of a phenyl group to 3-benzylidene quinuclidine derivative only results in an 18-fold increase in binding affinity, without conferring agonism. We also found that docking into the orthosteric binding site of the α4β2 nAChR is consistent with the fact that the basic nitrogen atom donates a hydrogen-bond to the carbonyl group of the highly conserved Trp-149, as initially observed by Dougherty and co-workers.¹ The experimentally-observed trend in binding affinity at both α4β2 and α3β4 nAChRs was accurately and independently confirmed by quantum mechanics (QM)-polarized docking. The reduction in binding affinity to the α3β4 subtype primarily results from a dampening of both coulombic and cation–π interactions.     

Study of fractal properties of single ionic channel gating mechanism by the fast Fourier transform]

Sets of the channel open times (tau o), closed times (tau c) and the full set of the channel open and closed times (tau o, tau c) in the activity of single Ca(2+)-activated K+ channels in cultured kidney cells Vero were analyzed using the fast Fourier transform. It was found that in the low-frequency range (about 0.01-10 Hz), power density can be described by the equation S(f) approximately f-alpha (as a rule, 0 < alpha < 1), and this part of the Fourier spectrum usually consists of narrow peaks at almost multiple frequencies. It was shown that the upper frequency boundary of this spectrum is determined by the kinetic parameters tau o [symbol: see text] tau c. The data obtained show that ion channel gating is a fractal process (correlated in time) and can be regarded as a random signal modulated by some periodical functions (sinuses). The data obtained by the Fourier method are in agreement with the earlier results obtained using the rescaled-range analysis.     

Inhibition of the endocrine function of the rat thymus by x-irradiation

Whole-body X-irradiation of rats caused inhibition of endocrine function of thymus. The effect was a function of radiation dose and time after irradiation. 72 h following irradiation with doses of 6 and 8 Gy the thymus hormone content of blood serum fell down the level registered in the thymectomized animals. Cellularity of the thymus and spleen concurrently decreased. The kinetics of spontaneous chemiluminescence of blood serum, thymus and spleen cells characterized the hypersecretion of glucocorticoids in response to radiation activation of lipid peroxidation in radiosensitive rat organs.     

Novel transcriptional responses to heat revealed by turning up the heat at night

Plant Molecular Biology - Genome-wide association study of maize plant architecture using F1 populations can better dissect various genetic effects that can provide precise guidance for genetic...     

Dependence of the cocarcinogenic action of the influenza virus on the nature of the influenza infection

It was shown in experiments of CC57W mice that cocarcinogenic activity of influenza A/PR8/34 virus correlates with acute or chronic pattern of infection. Prolonged persistence of the virus resulted in significant stimulation of the lung tumor incidence in infected mice. The prevention with thymosin of chronic influenza infection development in CC57W mice lead to a decrease in the incidence of lung tumors to the control level.     

Identification of the functional groups of yeast thiamine pyrophosphokinase]

The content of free sulfhydril groups in yeast thiamine pyrophosphokinase (EC 2.7.6.2) was studied. Their blocking was found not to affect considerably the enzyme activity. N-bromsuccinimide developes the inhibitory effect only if taken in excessive concentrations, which indicates that tryptophane has no key position for the enzyme-substrate complex formation. On account of high speed of photoinactivation with Rose bengale and methilene blue, sigmoid dependence of activity loss on pH under irradiation, characteristic narrowing of the modified enzyme absorption spectrum, it is suggested that imidazole residue of the histidine is one of the functional groups of thiamine pyrophosphokinase.