Peripherally inserted central venous catheters and central venous catheters related thrombosis in post-critical patients.

Background: Peripherally inserted central venous catheters (PICC) have been proposed as an alternative to central venous catheters (CVC). The aim of this study was to determine the thrombosis rate in relation to PICC placement in patients discharged from the intensive care unit (ICU).

Methods: Data of patients admitted to the ICU (Careggi Teaching Hospital, Florence, Italy; January-August 2008) and discharged with a central venous device were sequentially studied.

Study of bradykinin conformation in the presence of model membrane by Nuclear Magnetic Resonance and molecular modelling.

The conformation of bradykinin (BK), Arg1-Pro2-Pro3-Gly4-Phe5-Ser6-Pro7-Phe8-Arg9, was investigated by Nuclear Magnetic Resonance (NMR) spectroscopy and Monte Carlo simulation in two different media, i.e. in pure aqueous solution and in the presence of phospholipid vesicles.

Electron spin resonance spectroscopy in drug delivery.

The finding of non-viral carriers for the delivery and release of pharmaceutical and biological compounds to ill organs and tissues is one of the most widely investigated topic in medicinal and biological chemistry in the last decades. Prior to being used as drug vehicles in the living organisms, all of the new carriers are required to be fully characterized from a physico-chemical point of view, with respect to stability, charge, size, mobility, etc. To this aim, several molecular and bulky techniques have been employed for characterization.

Effect of the preparation procedure on the structural properties of oligonucleotide/cationic liposome complexes (lipoplexes) studied by electron spin resonance and Zeta potential.

Lipoplexes with different surface charge were prepared from a short oligonucleotide (20 mer, dsAT) inserted into liposomes of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3-phospho-ethanolamine (DOPE). The starting liposomes were prepared by two different procedures, i.e.

Insertion of a magnesium(II)-octacarboranyl(hexylsulfanyl) porphyrazine into liposomes: a physico-chemical study.

The synthesis, characterization and liposome insertion of a novel magnesium(II) carboranyl-porphyrazine, i.e. [2,3,7,8,12,13,17,18-octakis-(1,2-dicarba-closo-dodecaboranyl)-hexylthio-5,10,15,20-porphyrazine]magnesium(II) complex, MgHECSPz, are described.

Small angle scattering and zeta potential of liposomes loaded with octa(carboranyl)porphyrazine.

In this work, the physicochemical characterization of liposomes loaded with a newly synthesized carboranyl porphyrazine (H2HECASPz) is described. This molecule represents a potential drug for different anticancer therapies, such as boron neutron capture therapy and for photodynamic therapy or photothermal therapy. Different loading methods and different lipid mixtures were tested.

DOTAP/DOPE and DC-Chol/DOPE lipoplexes for gene delivery studied by circular dichroism and other biophysical techniques.

Cationic liposomes give rise to stable complexes with DNA molecules (lipoplexes) that are of great interest for gene delivery applications. In particular, liposomes made up by a cationic lipid (DOTAP or DC-Chol) and a zwitterionic lipid (DOPE), produce stable adducts with single and double-stranded DNA oligonucleotides. Formation of these lipoplexes has been further addressed here by circular dichroism spectroscopy (CD) and by other independent biophysical methods.

Solution behavior of a sugar-based carborane for boron neutron capture therapy: a nuclear magnetic resonance investigation.

The physico-chemical properties of beta-lactosyl-closo-orthocarborane in water solution were investigated by multinuclear NMR, (13)C NMR relaxation, and ab-initio calculations. This molecule represents a potentially selective boron carrier in Boron Neutron Cancer Therapy (BNCT) and exhibits amphiphilic characteristics. Its structural and dynamic features were studied comparing NMR data acquired in both aggregating and non-aggregating conditions.

Physico-chemical characterization and transfection efficacy of cationic liposomes containing the pEGFP plasmid.

Cationic liposomes-DNA complexes (lipoplexes) are largely used in gene delivery. Deciphering specific chemical and physical properties of lipoplexes is a necessary step to unravel the mechanisms underlying transfection and to improve transfection efficacy in each experimental model. In the present paper we investigated the physico-chemical features of lipoplexes containing a plasmid encoding for the GFP protein, in order to correlate these results with transfection efficacy.

ESR as a valuable tool for the investigation of the dynamics of EPC and EPC/cholesterol liposomes containing a carboranyl-nucleoside intended for BNCT.

Electron Spin Resonance (ESR) spectroscopy of long-chain nitroxides (5-, 7-, and 16-doxyl stearic acid) has been used to evaluate the perturbations induced by beta-5-o-carboranyl-2'-deoxyuridine (CDU) on the structure and dynamics of egg phosphatidylcholine (EPC) and EPC/cholesterol liposomes. Loaded liposomes are intended for the use in Boron Neutron Capture Therapy (BNCT). From a detailed analysis of the motional and order parameters determining the ESR line shape as a function of temperature and of CDU content in liposomes, an increased order and a hindered motion of the phospholipid membranes resulted in the presence of increasing CDU concentration.

Boronphenylalanine insertion in cationic liposomes for Boron Neutron Capture Therapy.

Cationic liposomes are widely used as carriers of biomolecules specifically targeted to the cell nucleus. p-Boronphenylalanine (BPA) is a powerful anti-tumor agent for Boron Neutron Capture Therapy (BNCT). In this paper, (1)H and (13)C NMR was used to study the insertion of BPA in mixed liposomes, made up by the positively charged 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and the zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE).

DOTAP/DOPE and DC-Chol/DOPE lipoplexes for gene delivery: zeta potential measurements and electron spin resonance spectra.

Non-viral vectors represent an important alternative in gene delivery. Among these vectors, cationic liposomes are widely studied, because of their ability to form stable complexes with DNA fragments (lipoplexes). In the present work, we report on the characterization by electron spin resonance (ESR) spectroscopy and zeta potential measurements of cationic liposomes and of their complexes with oligonucleotides.

Association of sugar-based carboranes with cationic liposomes: an electron spin resonance and light scattering study.

The possibility of cationic (di-oleoyltrimethylammonium propane, DOTAP)/(L-alpha-dioleoylphosphatidyl-ethanolamine, DOPE) liposomes to act as carriers of boronated compounds such as 1,2-dicarba-closo-dodecaboran(12)-1-ylmethyl](beta-D-galactopyranosyl)-(1-->4)-beta-D-glucopyranoside and 1,2-di-(beta-D-gluco-pyranosyl-ox)methyl-1,2-dicarba-closo-dodeca-borane(12) has been investigated by Electron Spin Resonance (ESR) of n-doxyl stearic acids (n-DSA) and Quasi-Elastic Light Scattering (QELS). Both these carboranes have potential use in Boron Neutron Capture Therapy (BNCT), which is a targeted therapy for the treatment of radiation resistant tumors. They were shown to give aggregation both in plain water and in saline solution.

Evidences of strong C-H...O bond in an o-carboranyl beta-lactoside in solution.

In this communication, the presence of a persistent intramolecular C-H...