Serotonergic organization of the central nervous system.

The last 50 years of researches of biochemism and the CNS functionality are intensively engaged in studying the role of monoamine neurotramsmitter serotonin (5-hydroxytryptamin) (5-HT). The serotonergic receptors function depends on spot where the receptor function, the dynamic relationship with other transmitters and stimulation that can activate or inhibit specific neurons. The results of research in biochemistry, neurophysiology and neuroradiology have provided insight into the complexity of the operation of key structures such as the amygdala, prefrontal cortex and hippocampus, whose role varies depending on the received external impulses and the impulses that are sent to relevant areas. This implies that the transmitters and especially 5-HT, have much wider effects that are determined not to structures but by the impulse dynamics. It also means that psychopharmaceutical drugs whose therapeutic effect is based on the change of the concentration of serotonin in the synapse and the postsynaptic receptors depending on where they operate, have an effect on affective or cognitive symptoms. Serotonergic antidepressants by changing the concentration of serotonin change primarily affective manifestations but also they have significant influence on all the spectrum of serotonergic disorders not only emotional, but also the cognitive level, which is also a confirmation that the therapeutic effects do not depend only on the simple change of serotonin concentration but also of the level where these changes occur in dynamic comparison of key transmitters. Atypical antipsychotics which have low affinity for dopaminergic and high affinity for serotonergic receptors are seen through the dynamic relationship of serotonin, dopamine and noradrenalin in nigrostriatal, mezocortical, mezolimbic and tuberoinfudibular pathways.

Subterminal deletion/duplication event in an affected male due to maternal X chromosome pericentric inversion.

UNLABELLED: We report a 13-month-old male infant with an apparently normal karyotype, severe growth and developmental delay, ichthyosis, hypogonadism, limb shortness, hypoplasia of the corpus callosum and a round, flat face and thin upper lip as a consequence of a subtelomeric del/dup event of the X chromosome. The recombinant X chromosome (rec(X)), derived from crossing-over within the inversion, was identified in a family, in which the mother is a carrier of pericentric inversion of one X chromosome and pericentric inversion of the heterochromatic region of chromosome 9. The inv(X) chromosome was also analysed in her sister and daughter. The rec(X) had a duplication of the segment Xq27.3-->Xqter and deletion of the Xp22.31-->Xpter and was interpreted as Xqter-Xq27.3::Xp22.31-Xqter. The rec (X) was characterised by FISH using a number of BAC probes. There are only three published reports of chromosome rearrangements resulting in a similar subtelomeric duplication of Xq in males. The proband's phenotype corresponds to descriptions of contiguous gene syndromes due to deletion of the STS, SHOX, ARSE and KAL genes. Despite the loss of the ARSE gene there was no evidence of chondrodysplasia punctata. Additional conditions associated with duplication of the Xq28 segment, such as severe growth retardation and developmental delay, a peculiar head shape, atrophy of the cerebral hemispheres and hypoplasia of the cerebellum and corpus callosum, were observed. CONCLUSION: Fluorescent in situ hybridisation techniques using subtelomeric DNA probes are essential tools for detection of such complex submicroscopic chromosomal rearrangements as the dup/del event of the X chromosome described in our patient.

The nptA gene of Vibrio cholerae encodes a functional sodium-dependent phosphate cotransporter homologous to the type II cotransporters of eukaryotes.

The nptA gene of Vibrio cholerae has significant protein sequence homology with type II sodium-dependent phosphate (P(i)) cotransporters found in animals but not previously identified in prokaryotes. The phylogeny of known type II cotransporter sequences indicates that nptA may be either an ancestral gene or a gene acquired from a higher eukaryotic source. The gene was cloned into an expression vector under the control of an inducible promoter and expressed in Escherichia coli. The results demonstrate that nptA encodes a functional protein with activity similar to that of the animal enzyme, catalyzing high-affinity, sodium-dependent P(i) uptake with comparable affinities for both sodium and phosphate ions. Furthermore, the activity of NptA is influenced by pH, again in a manner similar to that of the NaPi-2a subtype of the animal enzyme, although it lacks the corresponding REK motif thought to be responsible for this phenomenon. P(i) uptake activity, a component of which appeared to be sodium dependent, was increased in V. cholerae by phosphate starvation. However, it appears from the use of a reporter gene expressed from the nptA promoter that none of this activity is attributable to the induction of expression from nptA. It is thus proposed that the physiological function of NptA protein may be the rapid uptake of P(i) in preparation for rapid growth in nutrient-rich environments and that it may therefore play a role in establishing infection.