Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model.

Purpose: In this study, the (188)Re-labeled PEGylated nanoliposome ((188)Re-liposome) was prepared and evaluated as a therapeutic agent for glioma.

Materials And Methods: The reporter cell line, F98(luc) was prepared via Lentivector expression kit system and used to set up the orthotopic glioma-bearing rat model for non-invasive bioluminescent imaging. The maximum tolerated dose applicable in Fischer344 rats was explored via body weight monitoring of the rats after single intravenous injection of (188)Re-liposome with varying dosages before the treatment study.

⁹⁹mTc pyrene derivative complex causes double-strand breaks in dsDNA mainly through cluster-mediated indirect effect in aqueous solution.

Radiation therapy for cancer patients works by ionizing damage to nuclear DNA, primarily by creating double-strand breaks (DSB). A major shortcoming of traditional radiation therapy is the set of side effect associated with its long-range interaction with nearby tissues. Low-energy Auger electrons have the advantage of an extremely short effective range, minimizing damage to healthy tissue.

The effect of PEG-5K grafting level and particle size on tumor accumulation and cellular uptake.

PEG-modified gold nanoparticles (PEG-modified GNs) with diameters of 40 nm and 70 nm were prepared to elucidate the effect of extent of PEG (M.W. 5000) grafting and particle size on tumor accumulation and cellular uptake.

Poly(N-isopropylacrylamide) hydrogels with interpenetrating multiwalled carbon nanotubes for cell sheet engineering.

Hydrogels have been developed as artificial extracellular matrixes (ECMs) to mimic native tissue microenvironments for various applications. Unfortunately, poly(N-isopropylacrylamide) (PNIPAAM)-based hydrogels are not suitable for cell culturing and cell sheet preparation. Carbon nanotubes (CNTs), with their mechanical strength and electrical conductivity, have been considered as additives to increase the applicability of hydrogels to cell encapsulation and advance cardiac electrophysiological functions.

In vitro and in vivo evaluation of lactoferrin-conjugated liposomes as a novel carrier to improve the brain delivery.

In this study, lactoferrin-conjugated PEGylated liposomes (PL), a potential drug carrier for brain delivery, was loaded with radioisotope complex, 99mTc labeled N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (99mTc-BMEDA) for in vitro and in vivo evaluations. The hydrophilicity of liposomes was enhanced by PEGylation which was not an ideal brain delivery system for crossing the blood brain barrier (BBB). With the modification of a brain-targeting ligand, lactoferrin (Lf), the PEGylated liposome (PL) might become a potential brain delivery vehicle.

In vivo examination of 111In-bis-5HT-DTPA to target myeloperoxidase in atherosclerotic ApoE knockout mice.

Purpose: The aim of the study is to assess the feasibility of imaging specific activity of myeloperoxidase (MPO), a leukocyte-derived enzyme with important role in atherosclerosis, by SPECT/CT using a novel radiotracer, (111)In-bis-5-hydroxytryptamide-diethylenetriamine-pentaacetate ((111)In-bis-5HT-DTPA).

Methods: Bis-5HT-DTPA was synthesized. Oligomerization of bis-5HT-DTPA in the presence of MPO/H(2)O(2) was studied and confirmed using MALDI-TOF.

Combination of RGD compound and low-dose paclitaxel induces apoptosis in human glioblastoma cells.

Background: Integrins are a family of transmembrane adhesion proteins that mediate cell adhesion and intracellular signaling. Integrin-αvβ3 is expressed on the surface of human glioblastoma cells, and can be further induced by chemical stress. The Arg-Gly-Asp (RGD) motif-containing peptides are specifically bound to integrin-αvβ3, and to inhibit neovasculature underlying competition to normal extracellular matrix proteins.

In vivo imaging of radiation-induced tissue apoptosis by (99m)Tc(I)-his (6)-annexin A5.

Objective: A recombinant annexin A5 with the N-terminal extension of six histidine residues was labeled with (99m)Tc(I)-tricarbonyl ion to produce the (99m)Tc-labeled annexin A5, referred to (99m)Tc(I)-his(6)-annexin A5. We have explored the agent as an effective imaging probe for in vivo detecting the apoptosis of internal tissue subjected with high radiation doses in a γ-irradiated mouse model.

Methods: [(99m)Tc(CO)(3)(OH(2))(3)](+) was prepared and taken to directly label his(6)-annexin A5.

Imaging, autoradiography, and biodistribution of (188)Re-labeled PEGylated nanoliposome in orthotopic glioma bearing rat model.

The (188)Re-labeled pegylated nanoliposome (abbreviated as (188)Re-Liposome) was prepared and evaluated for its potential as a theragnostic agent for glioma. (188)Re-BMEDA complex was loaded into the pegylated liposome core with pH 5.5 ammonium sulfate gradient to produce (188)Re-Liposome.

Novel geometry type of nanocarriers mitigated the phagocytosis for drug delivery.

Target geometry for mitigating phagocytosis has garnered considerable attention recently in the drug delivery field. This study examined nanoparticles (NPs) with same volume but different shapes, namely, spherical NPs (SNPs) and hexagonal nanoprisms (HNPs), and analyzed their behaviors in vitro and in vivo. These NPs were constructed with a multifunctional block copolymer component, mPEG-b-P(HEMA-co-histidine-PLA).

In vivo examination of (188)Re(I)-tricarbonyl-labeled trastuzumab to target HER2-overexpressing breast cancer.

Introduction: Trastuzumab (Herceptin), a humanized IgG1 monoclonal antibody directed against the extracellular domain of the HER2 protein, acts as an immunotherapeutic agent for HER2-overexpressing human breast cancers. Radiolabeled trastuzumab with beta- or alpha emitters can be used as radioimmunotherapeutic agent for the similar purpose but with additional radiation effect.

Methods: In this study, trastuzumab was labeled with (188)Re for radioimmunotherapy of HER2/neu-positive breast cancer.

Comparison of bioactivities of 5-Fluoro, 5-Iodo, 5-Iodovinyl, and 5-fluorovinyl arabinosyl uridines against SR-39 TK-transfected murine prostate cancer cells.

A cell survival assay of the four arabinosyl uridine analogs with functionalities of 5-fluoro, 5-fluorovinyl, 5-iodo, and 5-iodovinyl as potential positron-emitter tagged probe for monitoring cancer gene therapy were performed. Cytotoxicities of 5-fluoro-, 5-iodo-, 5-fluorovinyl, and 5-iodovinyl arabinosyl uridines against SR-39 thymidine kinase transfected murine prostate cancer cells have been evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. None of them showed significant bioactivity.

Direct 99m Tc labeling of Herceptin (trastuzumab) by 99m Tc(I) tricarbonyl ion.

By simply incubating Herceptin (trastuzumab) with [99m Tc(CO)3(OH2)3]+ ion in saline, a significant yield of 99m Tc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which 99m Tc(I) tricarbonyl ion can be strongly bound. For practical 99m Tc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, alpha-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [99m Tc(CO)3(OH2)3]+.

New oxorhenium(V) complexes with 2N2S donor sets and radiochemical behavior of their technetium analogs.

Oxorhenium(V) complexes of two thioether amines have been synthesized and characterized spectroscopically. The five-coordinated ReO(3+) moiety is satisfied by the amine compounds behaving as dibasic tetradentate (NSSN) ligands and a chloride ion. The radioanalytical studies of their technetium analogs have been carried out at different pH values in the range 3-10.

micro-Oxo-bis{{2,2'-[2,2-dimethylpropane-1,3-diylbis(nitrilomethylidyne)]diphenolato}oxorhenium(V)}.

The title compound, [Re(2)O(3)(C(19)H(20)N(2)O(2))(2)], is a hexacoordinate complex containing an [Re(2)O(3)](4+) core with a linear O=Re-O-Re=O bridge. The distorted octahedral coordination of the Re(V) atom is achieved by an N(2)O(2) donor set from the tetradentate imine-phenol ligand. The overall charge of the compound is neutral due to deprotonation of the phenol groups, and the terminating and bridging O atoms.

3,3,10,10-tetramethyl-1,2-dithia-5,8-diazacyclodeca-4,8-diene.

The title compound, C(10)H(18)N(2)S(2), acts as an important precursor for the synthesis of the pharmaceutically important diaminedithiol ligand system. The molecule has a local twofold axis and the arrangement of the S(2)N(2) donor atoms in the macrocycle is anticlinal.

Monoprotic Tetradentate N(3)O-Donor Ligands and Their Cu(II) and Ni(II) Complexes.

A convenient four-step procedure was developed to prepare the novel monoprotic tetradentate ligands N-(2-hydroxy)benzyl-N-methyl-N'-(2-pyridyl)methyl-1,3-propanediamine (Hpamap) and N-(2-hydroxy)benzyl-N'-methyl-N'-(2-pyridyl)methyl-1,3-propanediamine (Hpmaap), which provide an N(3)O metal coordination sphere. A mononuclear copper(II) complex, [Cu(pamap)Cl] (A), was obtained by reaction of Hpamap with CuCl(2).2H(2)O.