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Reactions of Re V , tetradentate Schiff base complexes with tertiary phosphines have previously yielded both rearranged Re V and reduced Re III complexes. To further understand this chemistry, the rigid diiminediphenol (N 2 O 2 ) Schiff base ligand sal 2 phen (N,N'-ophenylenebis(salicylaldimine)) was reacted with (n-Bu 4 N) [ReOCl 4 ] to yield trans-[ReOCl(sal 2 phen)] (1). On reaction with triphenylphosphine (PPh 3 ), a rearranged Re V product cis-[ReO(PPh 3 )(sal 2 phen*)]PF 6 (2), in which one of the imines was reduced to an amine during the reaction, and the reduced Re III products trans-[ReCl(PPh 3 )(sal 2 phen)] (4) and trans-[Re(PPh 3 ) 2 (sal 2 phen)] + (5) were isolated. Reaction of sal 2 phen with [ReCl 3 (PPh 3 ) 2 (CH 3 CN)] resulted in the isolation of [ReCl 2 (PPh 3 ) 2 (salphen)] (3). The compounds were characterized using standard spectroscopic methods, elemental analyses and single crystal X-ray crystallography.

Introduction-Human breast cancer, from which the T-47D cell line was derived, is known to overexpress the gastrin-releasing peptide receptor (GRPR) in some cases. Bombesin (BBN), an agonist for the GRPR, has been appended with a radionuclide capable of positron-emission tomography (PET) imaging and therapy. 64 Cu-NO2A-8-Aoc-BBN(7-14)NH 2 (NO2A=1,4,7-triazacyclononane-1,4-diacetate) has produced high-quality microPET images of GRPR-positive breast cancer xenografted tumors in mice.Methods-The imaging probe was synthesized by solid-phase peptide synthesis followed by manual conjugation of the 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) bifunctional chelator and radiolabeling in aqueous solution. The radiolabeled conjugate was subjected to in vitro and in vivo studies to determine its specificity for the GRPR and its pharmacokinetic profile. A T-47D tumor-bearing mouse was imaged with microPET/CT and microMRI imaging.Results-The 64 Cu-NO2A-8-Aoc-BBN(7-14)NH 2 targeting vector was determined to specifically localize in GRPR-positive tissue. Accumulation was observed in the tumor in sufficient quantities to allow for identification of tumors in microPET imaging procedures. For example, uptake and retention in T-47D xenografts at 1, 4 and 24 h were determined to be 2.27±0.08, 1.35±0.14 and 0.28 ±0.07 % ID/g, respectively. Conclusions-The 64 Cu-NO2A-8-Aoc-BBN(7-14)NH 2 produced high-quality microPET images. The pharmacokinetic profile justifies investigation of this bioconjugate as a potentially useful diagnostic/therapeutic agent. Additionally, the bioconjugate would serve as a good starting point for modification and optimization of similar agents to maximize tumor uptake and minimize nontarget accumulation. NIH Public Access

[99mTc(CO)3-DTMA-(X)-BBN(7-14)NH2] conjugates displayed very high affinity for the gastrin releasing peptide receptor in vitro and in vivo. Therefore, these conjugates hold some propensity to be investigated as molecular imaging agents that specifically target human cancers uniquely expressing the gastrin releasing peptide receptor subtypes.

Peer mentoring has emerged as a viable retention strategy to aid higher education institutions in their efforts to ensure freshmen students make it through that crucial first year and beyond and obtain that degree. Although peer mentoring has been in existence for decades and, there is increasing research on this topic, there are no reviews of the literature more recent than 2009. Utilizing an integrative literature review, the research presented in this article provides an overview of current existing peer mentoring literature specific to its impact on stress and adjustment in the first year of college and retention outcomes in higher education. Findings from this study are aimed at informing best practices in first-year college retention efforts and raising awareness among higher education professionals on the psychosocial challenges many college freshmen bring with them and how it can negatively impact retention outcomes.

Purpose of review The purpose of the present review is to describe new, innovative strategies of diagnosing and treating specific human cancers using a cadre of radiolabeled regulatory peptides. Recent findings Peptide receptor-targeted radionuclide therapy is a method of site-directed radiotherapy that specifically targets human cancers expressing a cognate receptor-subtype in very high numbers. Ideally, the procedure targets only the primary or metastatic disease and is minimally invasive, with little radiation damage to normal, collateral tissues. For treatment strategies of this type to be effective, it is critical to evaluate the toxicity of the treatment protocol, the radiation dosimetry of the therapeutic regimen, and the biological profile of the radiopharmaceutical, including biodistribution and pharmacokinetics of the drug. Site-directed molecular imaging procedures via γ-scintigraphy can address many of the critical issues associated with peptide receptor-targeted radionuclide therapy and it is, therefore, necessary to describe the effective balance between the clinical benefits and risks of this treatment strategy. Summary Continued development in the design or chemical structure of radiolabeled, biologically active peptides could do much to improve the targeting ability of these drugs, thereby creating new and innovative strategies for diagnosis or treatment of human cancers.

An active area of prostate cancer research is in the synthesis of radiolabeled peptides for in vivo tumor imaging or therapy. This method is possible since specific receptors are expressed in high concentration on certain tumor tissue. One receptor that is expressed in high concentration on prostate cancer tissue is the gastrin-releasing peptide (GRP). The amphibian peptide, bombesin (BBN), has high affinity and specificity to the GRP receptors; therefore, when BBN is radiolabeled with an appropriate radionuclide, noninvasive prostate tumor images and therapy can be obtained. The aim of this research was to produce kinetically inert bifunctional chelate complexes that would effectively contain the radionuclide Rhenium-188 (188Re), Technetium-99m (99mTc), Copper-64 (64Cu) or Bismuth-213 (213Bi).

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