Advances in Mineral Processing, Waste Recycling and Extractive Metallurgy.

The constant growth of the world economy and industry stimulates an increasing production of ferrous and non-ferrous metals, while the depletion of natural resources leads to demands for the development of new technologies for the processing of low-grade ores and the deep recycling of metallurgical and other anthropogenic wastes [...

Rare-Earth Elements Extraction from Low-Alkali Desilicated Coal Fly Ash by (NH)SO + HSO.

Coal fly ash (CFA) obtained from pulverized coal furnaces is a highly refractory waste that can be used for alumina and rare-earth elements (REEs) extraction. The REEs in this type of CFA are associated with a mullite and amorphous glassy mass that forms a core-shell structure. In this research, it was shown that complete dissolution of amorphous aluminosilicates from the mullite surface with the formation of the low-alkali mullite concentrate prior to sulfuric acid leaching with the addition of (NH)SO helps to accelerate the extraction of REEs.

The Discrepancy between Coal Ash from Muffle, Circulating Fluidized Bed (CFB), and Pulverized Coal (PC) Furnaces, with a Focus on the Recovery of Iron and Rare Earth Elements.

Coal ash (CA) is not only one of the most solid wastes from combustion, easily resulting in a series of concerns, but it is also an artificial deposit with considerable metals, such as iron and rare earth. The variation in the coal ash characteristics due to the origins, combustion process, and even storage environment has been hindering the metal utilization from coal ash. In this study, three ash sample from lab muffle, circulating fluidized bed (CFB), and pulverized coal (PC) furnace was derived for the discrepancy study from the combustion furnace, including properties, iron, and rare earth recovery.

Angiotensin II type 1 receptor blocker telmisartan inhibits the development of transient hypoxia and improves tumour response to radiation.

Hypoxic tumour cells are radiation-resistant and are associated with poor therapeutic outcome. A poorly understood source of tumour hypoxia is unstable perfusion, which exposes tumour cells to varying oxygen tensions over time creating "transiently" hypoxic cells. Evidence suggests that angiotensin II type 1 receptor blockers (ARBs) can improve tumour perfusion by reducing collagen deposition from cancer associated fibroblasts (CAFs).

Pharmacokinetics, radiation dosimetry, acute toxicity and automated synthesis of [F]AmBF-TATE.

Introduction: [F]AmBF-TATE is a somatostatin agonist that selectively binds to somatostatin receptor subtype 2 (SSTR2). For clinical translation, pharmacokinetics, radiation dosimetry, and acute toxicity of [F]AmBF-TATE were assessed with good laboratory practice (GLP) standards.

Methods: ICR mice were intravenously administered 0.

Hhox: Rigid Cyclohexane-Reinforced Nonmacrocyclic Chelating Ligand for [Ga]Ga.

A rigid chiral acyclic chelator Hhox was synthesized and evaluated for Ga-based radiopharmaceutical applications; it was compared to the previously reported hexadentate Hhox to determine the effect of a backbone reinforced from adding a chiral 1S,2S-trans-cyclohexane on metal complex stability, kinetic inertness, and pharmacokinetics. NMR spectroscopy and theoretical calculation revealed that [Ga(hox)] showed a very similar coordination geometry to that of [Ga(hox)], and only one isomer in solution was observed by NMR spectroscopy. Solution studies showed that the modification results in a significant improvement in the exceptionally high thermodynamic stability of [Ga(hox)] with a 1.

Recovery of rare earth elements from coal fly ash by integrated physical separation and acid leaching.

Coal fly ash (CFA) is one of the most promising secondary sources of rare earth elements and yttrium (REY). This research first studied the modes of occurrence of REY in CFA collected from a China's power generation plant which utilizes a coal feedstock with an elevated REY content. The fact that rare earth minerals remain in CFA and REY associate with metal oxides was proved by emission-scanning electron microscope with an energy-dispersive X-ray spectrometer.

One-Step F-Labeling and Preclinical Evaluation of Prostate-Specific Membrane Antigen Trifluoroborate Probes for Cancer Imaging.

After the identification of the high-affinity glutamate-ureido scaffold, the design of several potent F- and Ga-labeled tracers has allowed spectacular progress in imaging recurrent prostate cancer by targeting the prostate-specific membrane antigen (PSMA). We evaluated a series of PSMA-targeting probes that are F-labeled in a single step for PET imaging of prostate cancer. We prepared 8 trifluoroborate constructs for prostate cancer imaging, to study the influence of the linker and the trifluoroborate prosthetic on pharmacokinetics and image quality.

Hhox: Dual-Channel Oxine-Derived Acyclic Chelating Ligand for Ga Radiopharmaceuticals.

An acyclic hexadentate oxine-derived chelating ligand, Hhox, was investigated as an alternative to current chelators for Ga. The straightforward preparation of Hhox, involving only one or two steps, obviates the synthetic challenges associated with many reported Ga chelators; it forms a Ga complex of great stability (log K = 34.4) with a remarkably high gallium scavenging ability (pGa = -log[Ga] = 28.

Effects of Linker Modification on Tumor-to-Kidney Contrast of Ga-Labeled PSMA-Targeted Imaging Probes.

Ga-PSMA-11 is currently the most popular prostate-specific membrane antigen (PSMA) radioligand used in the clinic to detect prostate cancer and metastases. However, the high uptake of Ga-PSMA-11 in kidneys can create halo-artifacts resulting in lower detection sensitivity for lesions adjacent to the kidneys. In this study, we developed two Ga-labeled PSMA-targeted tracers, Ga-HTK01166 and Ga-HTK01167, based on Ga-PSMA-617 with the goal of improving tumor-to-kidney ratio compared to Ga-PSMA-11.

Preclinical Melanoma Imaging with Ga-Labeled α-Melanocyte-Stimulating Hormone Derivatives Using PET.

It is estimated that melanoma accounted for 76,380 new cases and 10,130 deaths in the United States in 2016. The melanocortin 1 receptor (MC1R) is highly expressed in the vast majority of melanomas, which makes it an attractive target for molecular imaging and radionuclide therapy. Lactam bridge-cyclized α-melanocyte-stimulating hormone (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH, or Nle-CycMSH) analogues have been successfully developed and studied for MC1R-targeted imaging, predominantly with single-photon emission computed tomography (SPECT).

2-F-Fluoroethanol Is a PET Reporter of Solid Tumor Perfusion.

Solid tumor perfusion is a proven variable of interest for predicting cancer aggression and response to therapy. Current methods for noninvasively imaging tumor perfusion with PET are limited by restricted accessibility and short half-lives of perfusion radiotracers. This study presents 2-F-fluoroethanol (2-F-FEtOH) as a perfusion reporter that can distinguish between tumors of varying perfusion levels and can be applied to screening drugs that modify tumor perfusion.

Radiolabeled R954 Derivatives for Imaging Bradykinin B1 Receptor Expression with Positron Emission Tomography.

Peptide receptors have emerged as promising targets for diagnosis and therapy. The aberrant overexpression of these receptors in different cancer subtypes allows for the adoption of new treatment strategies that complement conventional chemotherapies. Bradykinin B1 receptor (B1R) is a G protein-coupled receptor that is overexpressed in many cancers, with limited expression in healthy tissues.

Synthesis and evaluation of a Ga-labeled bradykinin B1 receptor agonist for imaging with positron emission tomography.

A novel Ga-labeled bradykinin B1 receptor (B1R) agonist, Ga-Z01115, was synthesized and evaluated for imaging with positron emission tomography (PET). Z01115 exhibited good binding affinity (K=25.4±5.

Targeting the Neuropeptide Y1 Receptor for Cancer Imaging by Positron Emission Tomography Using Novel Truncated Peptides.

The neuropeptide Y receptor (Y1R) is overexpressed in many human cancers, particularly breast cancer. Due to stability issues, limited success has been achieved for Y1R imaging agents, including full length and truncated neuropeptide Y (NPY) analogues. The goal of this study was to evaluate the possibility of using radiolabeled truncated NPY analogues to visualize Y1R expression in a preclinical model of Y1R-positive tumor.

An imaging agent to detect androgen receptor and its active splice variants in prostate cancer.

Constitutively active splice variants of androgen receptor (AR-Vs) lacking ligand-binding domain (LBD) are a mechanism of resistance to androgen receptor LBD-targeted (AR LBD-targeted) therapies for metastatic castration-resistant prostate cancer (CRPC). There is a strong unmet clinical need to identify prostate cancer patients with AR-V-positive lesions to determine whether they will benefit from further AR LBD-targeting therapies or should receive taxanes or investigational drugs like EPI-506 or galeterone. Both EPI-506 (NCT02606123) and galeterone (NCT02438007) are in clinical trials and are proposed to have efficacy against lesions that are positive for AR-Vs.

Radiolabeled B9958 Derivatives for Imaging Bradykinin B1 Receptor Expression with Positron Emission Tomography: Effect of the Radiolabel-Chelator Complex on Biodistribution and Tumor Uptake.

Bradykinin B1 receptor (B1R), which is upregulated in a variety of malignancies, is an attractive cancer imaging biomarker. In this study we optimized the selection of radiolabel-chelator complex to improve tumor uptake and tumor-to-background contrast of radiolabeled analogues of B9958 (Lys-Lys-Arg-Pro-Hyp-Gly-Cpg-Ser-d-Tic-Cpg), a potent B1R antagonist. Peptide sequences were assembled on solid phase.

Trimeric Radiofluorinated Sulfonamide Derivatives to Achieve In Vivo Selectivity for Carbonic Anhydrase IX-Targeted PET Imaging.

Unlabelled: Carbonic anhydrase IX (CA-IX), a transmembrane enzyme, mediates cell survival under hypoxic conditions and is overexpressed in solid malignancies. In this study, we synthesized four (18)F sulfonamide derivatives and evaluated their potential for imaging CA-IX expression with PET.

Methods: Azide derivatives of 2 carbonic anhydrase inhibitors, 4-(2-aminoethyl)benzenesulfonamide (AEBS) and 4-aminobenzensulfonamide (ABS), were coupled to radiosynthons with either 1 or 3 alkynes and a pendent ammoniomethyltrifluoroborate (AmBF3) to generate monovalent or trivalent enzyme inhibitors.

Imaging Bradykinin B1 Receptor with 68Ga-Labeled [des-Arg10]Kallidin Derivatives: Effect of the Linker on Biodistribution and Tumor Uptake.

Bradykinin B1 receptor (B1R) that is overexpressed in cancers but minimally expressed in normal healthy tissues represents an attractive biomarker for the development of cancer imaging agents. The goal of this study was to evaluate the effect of different linkers on the pharmacokinetics and tumor uptake of a B1R-targeting radio-peptide sequence, 68Ga-DOTA-linker-Lys-Arg-Pro-Hyp-Gly-Cha-Ser-Pro-Leu. Four peptides, SH01078, P03034, P04115, and P04168, with 6-aminohexanoic acid, 9-amino-4,7-dioxanonanoic acid, Gly-Gly, and 4-amino-(1-carboxymethyl)piperidine, respectively, as the linker were synthesized and evaluated.

Nitroimidazole-Containing H2dedpa and H2CHXdedpa Derivatives as Potential PET Imaging Agents of Hypoxia with (68)Ga.

(68)Ga is an attractive radiometal for use in positron emission tomography (PET) imaging. The success of (68)Ga-based agents is dependent on a chelator that exhibits rapid radiometal incorporation, and strong kinetic inertness to prevent transchelation of (68)Ga in vivo. The linear chelating agents H2dedpa (1,2-[[6-carboxypyridin-2-yl]methylamino]ethane) and H2CHXdedpa (CHX = cyclohexyl/cyclohexane) (N4O2) have recently been developed that bind Ga(3+) quickly and under mild conditions, ideal properties to be incorporated into a (68)Ga PET imaging agent.

(18)F-AmBF3-MJ9: a novel radiofluorinated bombesin derivative for prostate cancer imaging.

A novel radiofluorinated derivative of bombesin, (18)F-AmBF3-MJ9, was synthesized and evaluated for its potential to image prostate cancer by targeting the gastrin releasing peptide receptor (GRPR). AmBF3-MJ9 was prepared from an ammoniomethyl-trifluoroborate (AmBF3) conjugated alkyne 2 and azidoacetyl-MJ9 via a copper-catalyzed click reaction, and had good binding affinity for GRPR (Ki=0.5±0.

Comparative studies of three 68Ga-labeled [Des-Arg10]kallidin derivatives for imaging bradykinin B1 receptor expression with PET.

Unlabelled: Bradykinin B1 receptor (B1R) is a G-protein-coupled receptor that is overexpressed in a variety of cancers. B1R is not expressed in healthy tissues, making it an attractive cancer imaging marker. Previously, we reported selective uptake of (68)Ga-P03034 ((68)Ga-DOTA-dPEG2-Lys-Arg-Pro-Hyp-Gly-Cha-Ser-Pro-Leu) in B1R-positive (B1R+) HEK293T::hB1R tumor xenografts in mice.

(18)F-trifluoroborate derivatives of [des-arg(10)]kallidin for imaging bradykinin b1 receptor expression with positron emission tomography.

Bradykinin B1 receptor (B1R) is involved in pain and inflammation pathways and is upregulated in inflamed tissues and cancer. Due to its minimal expression in healthy tissues, B1R is an attractive target for the development of therapeutic agents to treat inflammation, chronic pain, and cancer. The goal of this study is to synthesize and compare two (18)F-labeled peptides derived from potent B1R antagonists B9858 and B9958 for imaging B1R expression with positron emission tomography (PET).

In vivo radioimaging of bradykinin receptor b1, a widely overexpressed molecule in human cancer.

The bradykinin receptor B1R is overexpressed in many human cancers where it might be used as a general target for cancer imaging. In this study, we evaluated the feasibility of using radiolabeled kallidin derivatives to visualize B1R expression in a preclinical model of B1R-positive tumors. Three synthetic derivatives were evaluated in vitro and in vivo for receptor binding and their ability to visualize tumors by PET.

An organotrifluoroborate for broadly applicable one-step 18F-labeling.

A new zwitterionic organotrifluoroborate is appended to three radiosynthons that afford undergo facile bioconjugation to several clinically relevant peptides and one enzyme inhibitor. Molecularly complex bioconjugates are (18)F-labeled in a single aqueous step in rapid time (<15 min) without HPLC purification to afford tracers in good yields (>200 mCi, 20-40%) at high specific activity (≥3 Ci/μmol) and at >98% purity. PET imaging shows in vivo stability and tumor uptake.