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Introduction: Nicotinic acetylcholine receptors (nAChRs) are widely expressed throughout several brain regions. Formation of the α4β2 and α7 subtypes in particular is involved in the organisation of different types of memory. Furthermore, due to their location, these receptors can control the release of various types of neurotransmitters and contribute to synaptic plasticity., Methods: Rats were divided into three groups, an experimental group (E), a sham-operated group, (S) and an intact group (T). In group E, stereotactic guidance was used to induce a chemical lesion with 1 μ/μL of 5,7-dihydroxytryptamine (5,7-DHT) in the anteroventral part of the dorsal raphe nucleus (DRN). In the sham-operated group (S), animals underwent surgery including delivery of the same excipient solution to the same site. The intact group (T) received no treatment whatsoever. Twenty days after surgery, animals in all groups were euthanised by decapitation to evaluate the expression of α4 and α7 nAChRs by means of molecular biology techniques., Results: 5-HT denervation of the rat PFC differentially modified the expression of α4 and α7 receptors: while α4 receptor expression increased, α7 expression decreased., Conclusion: Expression differences observed between the two subtypes may be due to their separate locations. The α4 subtype is found in postsynaptic locations and may be related to adaptive changes in postsynaptic cells, while the location of α7 is presynaptic. This explains why the lesion and the elimination of 5-HT fibres in the CPF would cause a decrease in α7 expression., (Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.)

Introduction: Short chain fatty acids (SCFA) acetate, propionate and butyrate are the major anions produced by the bacterial fermentation of dietary fiber (DF) in colon. Recently, butyrate has been recently studied because is important to maintain colonic functions and because it has been related with a protective effect in colorectal cancer, which is mainly, explained by its potential to regulate gene expression by inhibiting enzyme histonedeacetylase (HDAC). Several investigationsshown that SCFAreceptor GPR43 is involved insignal transduction mechanisms once they bind to ligands such as butyrate to generate different physiological effects in colonocytes., Objective: Determine if dietary fiber consumption from nopal (Opuntia ficus I.) containing a ratio of soluble-insoluble fiber 40/60, has a direct influence on the quantitative expression of butyrate-specific receptor GPR43., Methods: Wistar rats were fed with four different diets formulated at different concentrations of dietary fiber of 0, 5, 15 and 25% of dietary fiber from opuntia, respectively., Results and Discussion: The results shown an increase in the expression of GPR43 (93.1%) when rats was fed with a 5% fiber diet, using β-actin as a reference gene. The results of this investigation will contribute to determinate the relation of diet with intestinal health for the purpose of expanding the knowledge of butyric acid on colonic functions.

Background: Interleukin-10 (IL-10) is an important immunoregulatory cytokine that acts on antigen presenting cells by the inhibiting both the synthesis of cytokines, co-stimulatory and HLA class II molecules., Objective: To study the gene and protein expression of IL-10 in the mucosa from patients with ulcerative colitis (UC)., Methods: We studied 40 patients with UC and 18 controls without endoscopic evidence of intestinal inflammation. From rectal biopsies was determined the gene expression of IL- 10 by real time polymerase chain reaction (PCR). The detection of the protein in tissue was performed by immunohistochemistry., Results: patients with UC in remission had significantly higher expression of il-10 gene in mucosa compared to the group of patients with active UC (p = 0.01) and the control group (p = 0.05). All patients with active UC had pancolitis, while patients in remission from distal inflammation, 16 had extra-intestinal manifestations and 23 had mild to moderate inflammation with less than one relapse within a year. Patients with UC in remission had significantly higher expression of IL-10 gene in mucosa compared with the group of patients with active UC (p = 0.01) or the control group (p = 0.05)., Conclusions: The expression of IL-10 gene is increased in colonic mucosa from patients with UC in remission, confirming that it is an immunoregulatory cytokine that promotes remission in patients with UC.

In situ hybridization of the endogenous chromosomal RNA to the chromosomal DNA allowed us to detect that most of the subregions of the salivary gland polytene chromosomas of Drosophila melanogaster transcribe RNA although at different rates. The DNA melting curves of two chromosomal subregions showed that there should be some correlation between the rate of transcription and the macromolecular architecture of the nucleoprotein.

Nifurtimox and benznidazole have trypanostatic actions in vitro and inhibit the incorporation of [3H] thymidine, [3H] uridine and L-[3H] leucine in T. cruzi macromolecules. The effect of nifurtimox may be explained by (a) direct inhibition of nucleic acid biosynthesis, or (b) generation of the oxygen radicals in T. cruzi and therefore, only mechanism (a) should be valid. In order to obtain more information on the action of these drugs on T. cruzi, in the present study we examined the effect of nifurtimox and benznidazole on DNA, RNA and protein turnover in epimastigote (culture) forms of the parasite. Complementary experiments were performed with beta-lapachone that, like nifurtimox, generates oxygen radicals in T. cruzi. Epimastigotes (Tulahuen strain) at the exponential-phase of growth were cultured with [3H] thymidine, [3H] uridine or L-[3H] leucine to label DNA, RNA and protein, respectively. After incubation, the cells were washed free of radioactive precursor, resuspended in fresh medium and reincubated at 30 degrees C with nifurtimox (10 or 100 microM), benznidazole (38 or 380 microM) or beta-lapachone (1.6 or 7.8 microM), for 1-3 hours. Controls were incubated without drug. At one hour time intervals, sampler were taken, washed free of medium and filtered through 0.45 microns Metricel filters. The filters were washed with 10% trichloroacetic acid to remove the acid soluble material, and after drying, the radioactivity incorporated in DNA, RNA and protein was counted with a scintillation counter. The results show that after elimination of the labelled precursors, 3H activity in DNA, RNA and protein decayed as a function of the time of incubation. Nifurtimox, benznidazole and beta-lapachone, stimulated in all cases they decay of the incorporated radioactivity. Calculation of "half-life" values for DNA, RNA and protein(s) indicated that nifurtimox and beta-lapachone exerted their greatest effects on DNA while benznidazole increased the decay of DNA, RNA and protein to about the same extent. Taking into account the effects of nifurtimox and beta-lapachone on DNA stability, specific lesions (single-strand breaks) were investigated in DNA from control, nifurtimox, benznidazole or beta-lapachone treated epimastigotes. The number of single-strand breaks was (per 10(6)b) 25 with 100 microM nifurtimox, 1.4 with 380 microM benznidazole and 45 with 7.8 microM g-lapachone. Interestingly enough, after reincubation of nifurtimox-damaged epimastigotes in fresh medium for 24 hours, recovery of DNA lesions could be observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Incorporation of 14C-Uridine in pituitary RNA from adults or prepuberal female rats in vitro, incubated with synthetic LH-RH or hypothalamic extracts, was studied in this work. RNA synthesis was not increased by any of the assayed stimuli in adult female rat pituitaries. The 14C-Uridine incorporation in pituitary prepuberal female rats increased in presence of synthetic LH-RH or adult female hypothalamic extracts, but not in presence of prepuberal female hypothalamic extracts. The differences found in the in vitro behaviour between pituitaries from prepuberal and adult female rats, and between their respective hypothalamic extracts, are attributables to the evolution of these organs along the sexual maturing process.

Hematopoiesis is regulated by several hormones and protein factors, among them, erytropoietin (Ep) and granulopoietin (CSF: Colony Stimulating Factor) play the fundamental control activities inducing the differentiation of stem cells to red and white cells series, respectively. The action of serum inhibitors and cyclic nucleotides on hematopoietic process is not well understood at present time. In this work a rat serum-inhibiting activity was detected that diminished the in vitro [3H] uridine incorporation into rat bone marrow whole RNA. The experiments show that the inhibitory may have a platelet origin.

The effect of kinetin (10(-6) M and 10(-4) M) on the germinating capacity and incorporation of 8-C14 adenine into DNA, RNA and RNA Poly A+ of embryos and cotyledons from Lupinus multilupa L. seeds have been studied. Kinetin enhanced the germinative capacity of the seeds and the incorporation of 8-C14 adenine into DNA, RNA and Poly A+ of embryos and cotyledons. However, there seems to be no close relationship between the DNA and RNA biosynthesis of embryos and cotyledons and the ability of the seeds to germinate and their embryos to continue growing.