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We have described the fully automated syntehsis of ppetide-glycoconjugates. Test of activity was also done.

Most biological processes involve permanent and temporary interactions between different proteins: protein complexes often play key roles in human diseases and, as a consequence, molecules that prevent protein-protein interactions can be potential new therapeutic agents to treat diseases. Here, we describe a simplified approach by which small synthetic peptide libraries were screened to identify the inhibitors of the complex between phosphoprotein enriched in diabetes/phosphoprotein enriched in astrocytes15 (PED/PEA15) and D4?, a functional domain of the phospholipase D1, that is involved in the molecular mechanisms of insulin resistance occurring in type 2 diabetes. By using an enzyme-linked immunosorbent assay (ELISA)-based screening, performed on a fully automated platform, we analyzed two simplified peptide libraries in a positional scanning format. This screening led to the identification of small peptides able to inhibit PED/PEA15-D4? interaction. The selection of inhibitors was carried out employing combined competitive and direct experiments, through ELISA and surface plasmon resonance techniques, providing peptides with IC(50) values in the micromolar range. Our results showed that the protein complex PED/PEA15-D4? is susceptible to peptides having H-donor groups and aromatic rings on specific positions. These small sequences can be considered as promising scaffolds that could be converted into higher-affinity inhibitor compounds.

Peptides isolated from natural fonts are the object of several studies aimed at finding new molecules possessing antibacterial activity. We focused our studies on peptides originally isolated from the Royal Jelly, the jelleins and on some analogs having a UV reporter at the N- or C-terminus. We found that jelleins are mainly active against gram-positive bacteria; interestingly, they act in synergy with peptides belonging to the family of temporins such as temporin A and temporin B against Staphylococcus aureus A170 and Listeria monocytogenes.

VEGF receptors have been the target of intense research aimed to develop molecules able to inhibit or stimulate angiogenesis. Based on the x-ray structure of the complex placental growth factor-VEGF receptor 1,2, we designed a VEGF receptor-binding peptide reproducing the placental growth factor beta-hairpin region Gln(87)-Val(100) that is involved in receptor recognition. A conformational analysis showed that the designed peptide adopts the expected fold in pure water. Moreover, a combination of NMR interaction analysis and cell binding studies were used to demonstrate that the peptide targets VEGF receptors. The VEGF receptor 1(D2)-interacting residues were characterized at the molecular level, and they correspond to the residues recognizing the placental growth factor sequence Gln(87)-Val(100). Finally, the peptide biological activity was characterized in vitro and in vivo, and it showed a VEGF-like behavior. Indeed, the peptide activated VEGF-dependent intracellular pathways, induced endothelial cell proliferation and rescue from apoptosis, and promoted angiogenesis in vivo. This compound is one of the few peptides known with proangiogenic activity, which makes it a candidate for the development of a novel peptide-based drug for medical applications in therapeutic angiogenesis.

The deciphering of intracellular signaling pathways that are activated by the interaction between viral fusion peptides and cellular membranes are important for the understanding of both viral replication strategies and host defense mechanisms.

Reports on nucleobase-containing chiral peptides (both natural and artificial) and achiral pseudopeptides are reviewed. Their synthesis, structural features, DNA and RNA-binding ability, as well as some other interesting applications which make them promising diagnostic/therapeutic agents of great importance in many areas of biology and therapy are taken into critical consideration.

The conjugates of .beta.-cyclodextrins with R- or with S-Etodolac were characterized by NMR spectroscopy, and S-Etodolac alone was characterized by X-ray diffraction anal. In soln., the R-Etodolac conjugate is sol. in water; the other epimer shows a very low soly. The NMR characterization of the R-Etodolac conjugate in D2O shows that, in aq. soln., the Edotolac moiety is self-included in the cavity, while the NMR characterization in MeOH of both conjugates underlines that, in this solvent, the Etodolac moiety is not included in the CD cavity. The X-ray structure detn. of the S-Etodolac conjugate reveals a "sleeping swan"-like shape, with the covalently bonded Etodolac moiety being folded with the 8-Et group inserted inside the hydrophobic cavity of the .beta.-CD ring. The terminal Me group of the 8-Et group enters the center of cavity from the side of the primary hydroxyl groups and is buried inside the .beta.-CD macrocycle. The terminal Me group is positioned at a distance of 1.06 .ANG. from the O(4) plane in the side of the primary hydroxyl groups. In addn. to van der Waals interactions between the hydrophobic Et group and the .beta.-CD cavity, the folded conformation is further stabilized by one intramol. H-bond involving the indole N-H group and the primary hydroxyl group of the glucose unit 7. Along the b axis, the .beta.-CD mols. are arranged in columns; the macrocycles form a herring bone pattern, so that the cavity of each .beta.-CD mol. is closed at each end by neighboring mols. Within the layers, the .beta.-CD macrocycles are held together by a complicated intermol. hydrogen bond network, in which numerous water mols. and hydroxyl groups are involved.

Purpose: To test whether a novel bifunctional chimeric peptide comprising a cyclic Arg- Gly-Asp pentapeptide covalently bound to an echistatin domain can discriminate alpavbeta3 from alpavbeta5 integrin, thus allowing the in vivo selective visualization of alpavbeta3 expression by single-photon and positron emission tomography (PET) imaging. Experimental Design: The chimeric peptide was preliminarily tested for inhibition of alphavbeta3-dependent cell adhesion and competition of 125I-echistatin binding to membrane of stably transfected K562 cells expressing alpavbeta3 (Kalpavbeta3 ) or alphavbeta5 (Kalpavbeta5) integrin. The chimeric peptide was then conjugated with diethylenetriaminepentaacetic acid and la- beled with 111In for single-photon imaging, whereas a one-step procedure was used for labeling the full-length peptide and a truncated derivative, lacking the last five C-termi- nal amino acids, with 18F for PET imaging. Nude mice bearing tumors from Kalpavbeta3 , Kalpavbeta5, U87MG human glioblastoma, and A431 human epidermoid cells were subjected to single-photon and PET imaging. Results: Adhesion and competitive binding assays showed that the novel chimeric pep- tide selectively binds to alpavbeta3 integrin and does not cross-react with alpavbeta5. In agreement with in vitro findings, single-photon and PET imaging studies showed that the radiola- beled chimeric peptide selectively localizes in tumor xenografts expressing alpavbeta3 and fails to accumulate in those expressing alpavbeta5 integrin. When 18F-labeled truncated derivative was used for PET imaging, alpavbeta3 - and alpavbeta5-expressing tumors were visualized, indicating that the five C-terminal amino acids are required to differentially bind the two integrins. Conclusion: Our findings indicate that the novel chimeric Arg-Gly-Asp peptide, having no cross-reaction with alpavbeta5 integrin, allows highly selective alpavbeta3 expression imaging and monitoring. (Clin Cancer Res 2009;15(16):5224-33)

To verify whether the use of potentially inappropriate medications (PIMs) is associated with loss of independence in elderly in-patients by promoting adverse drug reactions (ADRs).Prospective observational study.Five hundred six patients aged 65 and older admitted to 11 acute care medical wards.In-hospital loss of one or more activities of daily living (ADLs) and three or more ADLs. PIMs were identified according to diagnosis-independent Beers criteria and ascertained by study physicians based on daily review of medical and nurse records. The relationship between risk factors and outcomes was assessed using logistic regression.Overall, 104 patients (20.6%) were taking at least one PIM at the time of admission (baseline users), and 49 (9.7%) were newly prescribed at least one PIM during their hospital stay. The loss of one or more ADLs occurred in 9.6% of baseline users, 16.3% of new users, and 8.5% of nonusers (P=.21) and that of three or more ADLs in 7.7% of baseline users, 12.2% of new users, and 4.8% of nonusers (P=.10). The lack of association was confirmed after correction for potential confounders, including ADRs. The occurrence of ADRs was strongly associated with both outcomes (odds ratio (OR)=7.80, 95% confidence interval (CI)=3.53-17.3 for the loss ofor =1 ADLs; OR=3.98, 95% CI=1.50-10.5 for the loss ofor =3 ADLs), but PIMs caused only six of 106 ADRs.ADRs to any drugs more than the use of PIMs might be associated with functional decline in elderly hospitalized patients, but because the power of this study was too limited to definitively exclude a direct relationship between PIMs and functional decline, this merits further investigation.

A solid state and solution conformation analyses of the cyclopentapetide has been carried out by X-ray and NMR techniques. The structre is compared with literature data on cyclic pentapetides.

Synthetic strategy for new substituted tetraphenylporphyrins and their iron(III) and manganese(II) complexes are reported together with NMR studies on free bases allowing identification of the porphyrin isomers.

Like cyclosporin A, cyclolinopeptide A binds specifically bovine cyclophilin A, inhibiting its peptidyl-prolyl cis-trans isomerase activity. We describe the protein interaction with several synthetic analogues of cyclolinopeptide A in terms of dissociation and inhibition constants evaluated by fluorescence and inhibition of the enzyme activity.

Peptide nucleic acids (PNAs) are oligonucleotide mimics widely used as antisense, antigene molecules, and biotechnological tools. Recently, several microarrays and other biosensors based on PNAs have been developed. The construction of PNA molecular beacons or light-up probes for DNA detection requires the labelling of the PNA moiety. Labels are usually attached at the C or N terminal end by a flexible linker or in the middle of a PNA sequence, substituting one PNA base with an artificial base or by attaching fluorophores to a modified PNA backbone. The need to develop simple protocols to label PNAs encouraged us to design a new procedure for the synthesis of -mercaptomethyl-modified PNA. Here we propose a new strategy for the synthesis of modified PNAs, bearing amino acid side chains. The synthesis is straightforward and is an improvement to the procedures reported so far, as it uses stable intermediates and proceeds with better yields.

PNAs are expected to be very active in altering the splicing pattern of target RNA sequences. Several reports have been published on this specific task, focused on analysis of PNA altering splicing and vehiculated with a variety of delivery systems. The conclusions, here reviewed, are that PNAs altering splicing have important biological effects. In our own laboratory, we have studied the in vitro effects of a 14-mer PNA targeting a portion of the b-globin gene intron 1, suggesting that this strategy might be of interest to counteract the excess production of b-globin. Furthermore, the data obtained on the same 14-mer PNA, conjugated to the SV40 NLS peptide (b-globin-PNA/NLS) to enhance the PNA concentration in cells, demonstrate that the NLS peptide does not interfere with inhibition of the splicing.