Peptide derived from plant defensins: A promising Ga radiolabelled agent for diagnostic of infection foci in PET.

The development of new radiopharmaceuticals for the detection of hidden infection foci has great relevance for early detection and the selection of the correct treatment, particularly in immunosuppressed patients. In that sense, the labelling of antimicrobial peptides (AMPs) that are capable of binding specifically to the pathogenic microorganism which causes the infection, should provide a sufficiently specific agent, able to distinguish an infection from a sterile inflammation. Defensins are particularly interesting molecules with antimicrobial activity, the EcgDf1 defensin was identified from the genome of a Uruguayan native plant, Erythrina crista-galli, the 'Ceibo' tree.

Development and Evaluation of Tc Tricarbonyl Complexes Derived from Flutamide with Affinity for Androgen Receptor.

With the objective to develop a potential Tc radiopharmaceutical for imaging the androgen receptor (AR) in prostate cancer, four ligands bearing the same pharmacophore derived from the AR antagonist flutamide were prepared, labeled with Tc, and their structures corroborated via comparison with the corresponding stable rhenium analogs. All complexes were obtained with high radiochemical purity. Three of the complexes were highly stable, and, due to their favorable physicochemical properties, were further evaluated using AR-positive and AR-negative cells in culture.

[ Tc]Tc-HYNIC-EcgDf21: A defensin short analogue with potential application in infection foci imaging.

Opportunistic infections are a problem of great relevance in public health and the precise detection and localization of infection in the early stages of the disease is of great importance for patient management as well as cost containment. Our proposal seeks to contribute to developing a new agent that meets the needs of diagnosis and follow-up of fungal and bacterial infections, focused on the design of a radiotracer with the potential for recognition of hidden infection foci. Defensins are plant antimicrobial peptides that not only show activity against plant pathogens but also against human ones.

Development and characterization of two novel Ga-labelled neuropeptide Y short analogues with potential application in breast cancer imaging.

In vivo receptor targeting with radiolabelled peptide-based probes is an attractive approach for the development of novel radiotracers for molecular imaging. This work presents the development and characterization of two novel neuropeptide Y analogues labelled with a positron emitter Ga, for potential use in breast cancer imaging. Both analogues share the same amino acid sequence and were derivatized with NOTA through either a lysine linker (L1) or an acetylated lysine (L2).

Development and characterization of a Tc-labeled Neuropeptide Y short analog with potential application in breast cancer imaging.

The aim of this work was to develop and evaluate a Tc-labeled neuropeptide Y derivative with affinity toward Y1-receptor. The selected amino acid sequence included nine amino acids derived from the C-terminal portion of the NPY complemented with the addition of one cysteine-mercaptoacetic acid moiety to bind the radiometal. Labeling was achieved through the preparation of a 3 + 1 nitrido complex.

Evaluation of a Labelled Bacteriophage with 99mTc as a Potential Agent for Infection Diagnosis.

Background And Objective: The design of target-specific molecular imaging probes to determine infection sites are mainly based on the biochemistry of the inflammatory response that may lead to an ideal agent for infection imaging. Infectious diseases timely and specifically diagnosed can be clinically challenging but essential for the patient's recovery. Laboratory tests can detect the responsible microorganism but cannot discriminate between sterile inflammatory disease and truly infectious disease.

¹⁷⁷Lu-Labeled Agents for Neuroendocrine Tumor Therapy and Bone Pain Palliation in Uruguay.

Lutetium-177 is an emerging radionuclide due its convenient chemical and nuclear properties. In this paper we describe the development and evaluation in Uruguay of the targeted 177Lu labelled radiopharmaceuticals EDTMP (for bone pain palliation) and DOTA-TATE (neuroendocrine tumors). We optimized the preparation of these 177Lu radiopharmaceuticals including radiolabelling, quality control methods, in vitro and in vivo stability and their therapeutic application in patients.

Biological studies in animal models using [99mTc](CO)3 recombinant annexin V as diagnostic agent of apoptotic processes.

Introduction: There are many diseases associated with variations in the expression of apoptosis such as organ rejection after transplantation, myocardial ischemia or infarct and neurodegenerative diseases. For this reason, the early visualization of this process is relevant to set fast and effective therapeutic strategies.

Methods: The precursor was prepared according to the procedure reported by R.

Hydrophilic and lipophilic radiopharmaceuticals as tracers in pharmaceutical development: in vitro--in vivo studies.

Background: Scintigraphic studies have been performed to assess the release, both in vitro and in vivo, of radiotracers from tablet formulations. Four different tracers with differing physicochemical characteristics have been evaluated to assess their suitability as models for drug delivery.

Methods: In-vitro disintegration and dissolution studies have been performed at pH 1, 4 and 7.

Usage of radiopharmaceuticals in the development of pharmaceutical drug delivery systems: validation of [99mTc]DTPA and [99mTc]ECD.

Tablets containing drugs of different lipophilicity, ranitidine and cinarizine, and placebo were prepared and their in vitro behaviour was studied by dissolution and disintegration tests. [(99m)Tc]Diethylenetriamine-pentaacetic acid ([(99m)Tc]DTPA) and [(99m)Tc]ethyl cysteinate dimer ([(99m)Tc]ECD) were used as tracers of the process. Both of them were added to tablets during wet granulation.