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Radionuclide-based Diagnosis and Therapy of Prostate Cancer
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Sven-Erik Strand, Mohamed Altai, Joanna Strand, David Ulmert
Bone metastases often lead to pain and fractures. Pain palliation with analgesic or external beam irradiation can have serious side effects. 32P, 89Sr, and 223Ra are so-called calcimimetic agents following calcium kinetics. Radionuclides can be labelled to phosphonates, with high affinity to bone minerals, be absorbed to calcium atoms and reduce pain by inducing apoptosis in osteoclasts. In therapy the most used phosphonate-based agents are 188Re-HEDP, 153Sm-EDTPM, and 177Lu-EDTMP. For bone palliation, 89Sr-chloride [111], 153Sm-lexidronam, and 186Re-etidronate, with pain relief being achieved in 60–80 per cent of patients [112]. Radionuclides used for phosphonate coupling and skeletal pain therapy are given in Lange and colleagues [64]. Table 19.4 lists the main physical characteristics for some radionuclides used for pain palliation in metastatic disease involving the bones.
Ene-Reductases in Pharmaceutical Chemistry
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Phosphonates have wide applications in chemistry and biomedicine as they inhibit enzymes involved in several biological processes such as peptidoglycan and isoprenoid biosynthesis. Particularly interesting are derivatives of fosmidomycin and fosfomycin (Scheme 10.9), the latter being a rare epoxide containing antibiotic (Falagas et al., 2016). Schematic representation of fosfomycin, a rare epoxide-containing antibiotic.
Radiopharmaceutical Therapy of Cancer
Published in Martin G. Pomper, Juri G. Gelovani, Benjamin Tsui, Kathleen Gabrielson, Richard Wahl, S. Sam Gambhir, Jeff Bulte, Raymond Gibson, William C. Eckelman, Molecular Imaging in Oncology, 2008
Daniel A. Pryma, Chaitanya R. Divgi
Samarium-153 EDTMP is a radiolabeled phosphate analog. The phosphonate is taken up by osteoblasts; thus, its incorporation at metastatic sites is by being analogous to phosphate rather than calcium. Samarium-153 emits cytotoxic β-particles and a 103 keV photon; the photon permits gamma camera imaging. The 46.3-hour half-life of samarium-153 allows for a higher dose rate in addition to a shorter period of toxicity. Overall, bone pain palliation is achieved in 70% to 95% of patients after therapy with samarium-153 EDTMP (22–24). Similar to therapy with strontium-90, toxicity is hematologic, generally mild and reversible with recovery in most patients by five weeks (25).
Bone targeted new zoledronate derivative: design, synthesis, 99mTc-coupling, in-silico study and preclinical evaluation for promising osteosarcoma therapy
Published in International Journal of Radiation Biology, 2022
Hend Fayez, Adli Abdallah Selim
Phosphonate-based radiopharmaceuticals are effective and safe agents for the treatment of painful bone metastases. Skeletal targeted radiotherapy (STR) is a novel approach to treat patients with diffuse malignant disease confined to the bone marrow. Low-energy beta-emitting radionuclides (153Sm, 188Re, 177Lu, etc.) deliver high radiation doses to bone metastases and micro-metastases in the bone marrow. Significant research with many compounds has been conducted over several decades, and some of them are clinically used such as 153Sm-EDTMP, 188Re-HEDP, 177Lu-EDTMP and 166Ho-DOTMP. Also, some researches were conducted by using the combination between bisphosphonates and alpha-emitter radionuclide such as 225Ac-EDTMP, 225Ac-DOTMP, 227Th-DOTMP and 212Pb/212 Bi-DOTMP (Breitz et al. 2003; Fischer and Kampen 2012; Bruland and Larsen 2013; Lange et al. 2016; Handkiewicz-Junak et al. 2018). We aimed in the near future to study the effect of nitroimidazole-bisphosphonate after labeling with beta-emitting therapeutic radionuclides (e.g. Samarium-153, Lutetium-177, Holmium-166, etc.) and alpha emitters (e.g. Ac-225) that could enhance the therapeutic effect of the new synthesized molecule reported in this research.
Evaluating the effect of antiscalants on membrane biofouling using FTIR and multivariate analysis
Published in Biofouling, 2019
Mohammad Y. Ashfaq, Mohammad A. Al-Ghouti, Hazim Qiblawey, Nabil Zouari
The membrane filtration technique is being adopted worldwide as an environmentally friendly and energy efficient technique in the desalination industry as compared to thermal desalination techniques (Tang et al. 2009, 2011; Sun et al. 2016). However, the performance of membranes, which includes permeate flux and rejection, is affected by the membrane fouling and scaling. To prevent mineral scaling on reverse osmosis (RO) membranes, antiscalants are added to suppress mineral scale formation. The most common antiscalants for calcium sulfate (CaSO4) include phosphonates and organic polymers (Shih et al. 2006). In RO systems, phosphonates, however, tend to hydrolyze to orthophosphate and react with calcium ions to form calcium orthophosphate, which is insoluble (Antony et al. 2011). Therefore, most of the commercial antiscalants for RO membranes are organic polymer-based chemicals, such as poly acrylic acid (PAA), polymethacrylic acid (PMAA), and poly maleic acid (PMA).
Transition state analogue imprinted polymers as artificial amidases for amino acid p-nitroanilides: morphological effects of polymer network on catalytic efficiency
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Divya Mathew, Benny Thomas, K. S. Devaky
Now it is exciting to compare the binding of the mimic to the substrate anilide and to the TSA. Binding to the anilide is evaluated from the Michaelis–Menten constant Km and binding to the TSA can be estimated from the competitive inhibition caused by the added TSA during the catalytic amidolysis (Ki). The influence of the inhibiting template molecule was monitored with amidase MIP C1, prepared in DMSO. Two different inhibitor concentrations were added to the amidolysis media. The velocities were monitored in the same way under the same conditions of amidolysis (1:9 ACN–Tris HCl buffer of pH 7.75 and 45 °C). Evidently, the phosphonate TSA is a very effective inhibitor that binds much better than the substrate S1 by a factor of 33.56 when TSA is present in half the concentration of the substrate PNA [Ki = 0.075 mmol and Km = 2.516 mmol] and by a factor of 66.70 when equal concentration of TSA and substrate are used [Ki = 0.056 mmol and Km = 3.735 mmol]. Since the straight lines intersect in the negative part of the plot the TSA not only bind with the polymer catalyst (C1–TSA), but also with the catalyst–substrate complex (TSA–C1–PNA). Since the exactness of the kinetic evaluation is not high enough, we have not calculated the different inhibitor constants.