Tae

The observation that overexpression of the anti-apoptotic protein Bcl-2 is associated with both cancer development and anti-cancer drug resistance suggests that factors which regulate bcl-2 expression may be important therapeutic targets. We report here that taxol or okadaic acid (OA) treatment of HL-60 cells reduced bcl-2 mRNA steady state levels to 50% of control cell levels in 20–24 hr of treatment. The 3′-untranslated region of bcl-2 mRNA contains four potential A+U-rich elements (AREs), which are associated with mRNA destabilization. RNA gel mobility shift assays revealed that HL-60 cell extracts contain proteins that bind to RNA transcripts containing the first bcl-2 ARE (ARE 1). ARE 1 binding activity was substantially reduced in extracts of cells treated for 20 hr with taxol or OA and was abolished after 32 hr of treatment. UV-induced RNA cross-linking assays revealed that untreated HL-60 cell extracts contain approximately eight proteins, ranging in size from 32 to 100 kDa, that bind to ARE 1 RNA. Following 20 hr of taxol or OA treatment, RNA cross-linking to ∼70 and ∼38 kDa proteins was greatly reduced, and cross-linking to four proteins of 45–60 kDa sizes was progressively reduced with 10–34 hr of OA or taxol treatment. Collectively, these results suggest a novel action of taxol and OA on bcl-2 expression, which involves bcl-2 mRNA downregulation through inactivation of bcl-2 mRNA stabilizing factors.

Gene therapy has the potential to provide safe and targeted therapies for a variety of diseases. A range of intracellular gene delivery vehicles have been proposed for this purpose. Non-viral vectors are a particularly attractive option and among them cationic peptides have emerged as promising candidates. For the pharmaceutical formulation and application to clinical studies it is necessary to quantify the amount of pDNA condensed with the delivery system. There is a severe deficiency in this area, thus far no methods have been reported specifically for pDNA condensed with cationic peptide to form nanoparticles. The current study seeks to address this and describes the evaluation of a range of disruption agents to extract DNA from nanoparticles formed by condensation with cationic fusogenic peptides RALA and KALA. Only proteinase K exhibited efficient and reproducible results and compatibility with the PicoGreen reagent based quantification assay. Thus we report for the first time ...

To elucidate the molecular phylogeny and evolution of a particular peptide, one must analyze not the limited primary amino acid sequences of the low molecular weight mature polypeptide, but rather the sequences of the corresponding precursors from various species. Of all the structural variants of gonadotropin-releasing hormone (GnRH), GnRH-II (chicken GnRH-II, or cGnRH-II) is remarkably conserved without any sequence substitutions among vertebrates, but its precursor sequences vary considerably. We have identified and characterized the full-length complementary DNA (cDNA) encoding the GnRH-II precursor and determined its genomic structure, consisting of four exons and three introns, in a reptilian species, the leopard gecko Eublepharis macularius. This is the first report about the GnRH-II precursor cDNA/gene from reptiles. The deduced leopard gecko prepro-GnRH-II polypeptide had the highest identities with the corresponding polypeptides of amphibians. The GnRH-II precursor mRNA was detected in more than half of the tissues and organs examined. This widespread expression is consistent with the previous findings in several species, though the roles of GnRH outside the hypothalamus–pituitary–gonadal axis remain largely unknown. Molecular phylogenetic analysis combined with sequence comparison showed that the leopard gecko is more similar to fishes and amphibians than to eutherian mammals with respect to the GnRH-II precursor sequence. These results strongly suggest that the divergence of the GnRH-II precursor sequences seen in eutherian mammals may have occurred along with amniote evolution.

The observation that overexpression of the anti-apoptotic protein Bcl-2 is associated with both cancer development and anti-cancer drug resistance suggests that factors which regulate bcl-2 expression may be important therapeutic targets. We report here that taxol or okadaic acid (OA) treatment of HL-60 cells reduced bcl-2 mRNA steady state levels to 50% of control cell levels in 20–24 hr of treatment. The 3′-untranslated region of bcl-2 mRNA contains four potential A+U-rich elements (AREs), which are associated with mRNA destabilization. RNA gel mobility shift assays revealed that HL-60 cell extracts contain proteins that bind to RNA transcripts containing the first bcl-2 ARE (ARE 1). ARE 1 binding activity was substantially reduced in extracts of cells treated for 20 hr with taxol or OA and was abolished after 32 hr of treatment. UV-induced RNA cross-linking assays revealed that untreated HL-60 cell extracts contain approximately eight proteins, ranging in size from 32 to 100 kDa, that bind to ARE 1 RNA. Following 20 hr of taxol or OA treatment, RNA cross-linking to ∼70 and ∼38 kDa proteins was greatly reduced, and cross-linking to four proteins of 45–60 kDa sizes was progressively reduced with 10–34 hr of OA or taxol treatment. Collectively, these results suggest a novel action of taxol and OA on bcl-2 expression, which involves bcl-2 mRNA downregulation through inactivation of bcl-2 mRNA stabilizing factors.

Desde sempre que se considerou imprescindível conhecer o contexto arqueológico das epígrafes, mormente em relação à época romana. Como são escassos os monumentos encontrados in situ, importa fazer cuidada análise da tipologia da epígrafe, a fim de com mais fundamento se propor a sua integração no seu contexto original. Apontam-se exemplos significativos da necessária complementaridade entre a Arqueologia e a Epigrafia.

This study was conducted on mice to evaluate the radioprotective role of L-carnitine against γ-ray irradiation-induced testicular damage. Adult male mice were exposed to whole body irradiation at a total dose of 1 Gy. Radiation exposure was continued 24 h a day (0.1 Gy/day) throughout the 10 days exposure period either in the absence and/or presence of L-carnitine at an i.p. dose of 10 mg/kg body weight/day. Results revealed that γ-rays irradiation suppressed the expression of ABP and CYP450SCC mRNA, whereas treatment with L-carnitine prior and throughout γ-rays irradiation exposure inhibited this suppression. Treatment with γ-ray irradiation or L-carnitine down-regulated expression of aromatase mRNA. With combined treatment, L-carnitine significantly normalized aromatase expression. γ-Ray irradiation up-regulated expression of FasL and Cyclin D2 mRNA, while L-carnitine inhibited these up-regulations. Results also showed that γ-ray-irradiation up-regulated TNF-α, IL1-β and IFN-γ mRNA expressions compared to either controls or the L-carnitine treated group. Moreover, γ-irradiation greatly reduced serum testosterone levels, while L-carnitine, either alone or in combination with irradiation, significantly increased serum testosterone levels compared to controls. In addition, γ-irradiation induced high levels of sperm abnormalities (43%) which were decreased to 12% in the presence of L-carnitine. In parallel with these findings, histological examination showed that γ-irradiation induced severe tubular degenerative changes, which were reduced by L-carnitine pre-treatment. These results clarified the immunostimulatory effects of L-carnitine and its radioprotective role against testicular injury.