1.Progress of Coordination and Utilization of Zirconium-89 for Positron Emission Tomography (PET) Studies
Minh Thanh LA ; Van Hieu TRAN ; Hee Kwon KIM
Nuclear Medicine and Molecular Imaging 2019;53(2):115-124
Radiometals have been commonly used in medical applications, and utilization of such metals continues to be an attractive research area. In particular, a variety of radiometals have been developed and implemented for molecular imaging. For such applications, ⁸⁹Zr has been one of the most interesting radiometals currently used for tumor targeting. Several chemical ligands were developed as ⁸⁹Zr chelators, and new coordinating methods have also been developed more recently. In addition, immunopositron emission tomography (PET) studies using ⁸⁹Zr-labeled monoclonal antibodies have been performed by several scientists. In this review, recent advances to the coordination of ⁸⁹Zr and the utilization of ⁸⁹Zr in PET studies are described.
Antibodies, Monoclonal
;
Chelating Agents
;
Electrons
;
Ligands
;
Metals
;
Molecular Imaging
;
Positron-Emission Tomography
2.Chelating effects of siderophore in reducing organ dysfunction caused by iron overload in ICR Mice
Thucydides L. Salunga ; Isabella R. Panelo ; Joel C. Cornista
Philippine Journal of Health Research and Development 2019;23(4):47-57
Background and Objectives:
Iron is an essential element that plays a vital role in a wide variety of cellular
processes. But when present in excess concentration in organs, it may increase the risk for liver disease, heart
failure, and diabetes. Recently, siderophores, which are iron-chelating agents produced by microorganisms,
have attracted tremendous attention because of their strong binding and high selectivity to the ferric form of
iron. Thus, the use of siderophore in sequestering excess iron in the body as a form of therapy is very attractive.
This study determined the effects of commercially available siderophore in sequestering excess iron in organs
such as liver, heart, and pancreas under excess iron conditions.
Methodology:
First, iron-overload was induced by injecting iron dextran (20 mg) into male ICR mice for three
consecutive days. The effects of iron to the liver, heart, and pancreas and the possible sequestration by
siderophore were determined by scoring histological sections. The liver iron concentration was also assessed
by atomic absorption spectroscopy (AAS).
Results and Conclusion
The study showed that iron-overloaded mice exhibited skin hyperpigmentation and
hemosiderosis in liver, heart, and pancreas. Significant changes in the liver include hepatomegaly and
development of tumor. Iron-overloaded mice had 2,935% increase in liver iron content compared to the salinetreated mice. However, when iron-overloaded mice were treated with either 100 µg or 200 µg siderophore,
there was a 77% and 84% decrease in liver iron content, respectively. Moreover, the treatment of ironoverloaded mice with siderophore prevented the development of hemosiderosis, tumor, and structural
changes in the tissues studied. The results showed that siderophore can effectively reduce excess iron and
organ damage in iron-overloaded mice and can be potentially employed in chelation therapy of iron-overload
diseases. Further studies on the possible mechanisms of siderophore aside from decreasing iron excess and
lowering organ dysfunction are recommended.
Siderophores
;
Iron Overload
;
Iron Chelating Agents
;
Hemosiderosis
;
Hepatomegaly
3.The toxicological mechanisms and detoxification of depleted uranium exposure.
Yong-Chao YUE ; Ming-Hua LI ; Hai-Bo WANG ; Bang-Le ZHANG ; Wei HE
Environmental Health and Preventive Medicine 2018;23(1):18-18
Depleted uranium (DU) has been widely applied in industrial and military activities, and is often obtained from producing fuel for nuclear reactors. DU may be released into the environment, polluting air, soil, and water, and is considered to exert both radiological and chemical toxicity. In humans and animals, DU can induce multiple health effects, such as renal tubular necrosis and bone malignancies. This review summarizes the known information on DU's routes of entry, mechanisms of toxicity, and health effects. In addition, we survey the chelating agents used in ameliorating DU toxicity.
Animals
;
Chelating Agents
;
pharmacology
;
Humans
;
Inactivation, Metabolic
;
Radiation-Protective Agents
;
pharmacology
;
Uranium
;
metabolism
;
toxicity
4.A Systematic Comparative Evaluation of ⁶⁸Ga-Labeled RGD Peptides Conjugated with Different Chelators
Akanksha JAIN ; Sudipta CHAKRABORTY ; H D SARMA ; Ashutosh DASH
Nuclear Medicine and Molecular Imaging 2018;52(2):125-134
PURPOSE: The present paper reports a systematic study on the effect of bifunctional chelators (BFC) namely, NOTA, DOTA, and DTPA, on the radiochemical formulation, in vitro stability, and in vivo biological properties of ⁶⁸Ga-labeled RGD peptide derivatives.METHODS: The three RGD conjugates namely, NOTA-Bn-E-[c(RGDfk)]₂, DOTA-Bn-E-[c(RGDfk)]₂, and DTPA-Bn-E-[c(RGDfk)]₂ were radiolabeled with ⁶⁸Ga and the radiolabeling was optimized with respect to the ligand amount, radiolabeling time, and temperature. Further, the ⁶⁸Ga complexes were assessed for their in vitro and in vivo stabilities. The biodistribution studies of the three radiolabeled conjugates were carried out in C57BL/6 mice bearing melanoma tumor at 30 min and 1 h post-adimistration.RESULTS: NOTA-Bn-E-[c(RGDfk)]₂ could be radiolabeled with ⁶⁸Ga at room temperature while DOTA-Bn-E-[c(RGDfk)]₂ and DTPA-Bn-E-[c(RGDfk)]₂ were radiolabeled at high temperature. ⁶⁸Ga-NOTA-Bn-E-[c(RGDfk)]₂ was found to be the most kinetically rigid in in vitro stability assay. The uptake of the three radiolabeled peptide conjugates in melanoma tumor was comparable at 1 h post-administration (NOTA; DOTA; DTPA (% I.D./g):: 2.78 ± 0.38; 3.08 ± 1.1; 3.36 ± 0.49). However, the tumor/background ratio of ⁶⁸Ga-NOTA-Bn-E-[c(RGDfk)]₂ was the best amongst the three radiotracers. ⁶⁸Ga-complexes of NOTA-Bn-E-[c(RGDfk)]₂ and DOTABn-E-[c(RGDfk)]₂ showed excellent in vivo stability while ⁶⁸Ga-DTPA-Bn-E-[c(RGDfk)]₂ showed significant metabolic degradation.CONCLUSION: These studies show that ⁶⁸Ga-NOTA-Bn-E-[c(RGDfk)]₂ would be the most appropriate ⁶⁸Ga-labeled radiotracer and the most amenable for kit formulation.
Animals
;
Chelating Agents
;
In Vitro Techniques
;
Melanoma
;
Mice
;
Pentetic Acid
;
Peptides
5.ASIC1a contributes to the symptom of pain in a rat model of chronic prostatitis.
Song FAN ; Zong-Yao HAO ; Li ZHANG ; Jun ZHOU ; Yi-Fei ZHANG ; Shen TAI ; Xian-Sheng ZHANG ; Chao-Zhao LIANG
Asian Journal of Andrology 2018;20(3):300-305
This study aims to validate our hypothesis that acid-sensing ion channels (ASICs) may contribute to the symptom of pain in patients with chronic prostatitis (CP). We first established a CP rat model, then isolated the L5-S2 spinal dorsal horn neurons for further studies. ASIC1a was knocked down and its effects on the expression of neurogenic inflammation-related factors in the dorsal horn neurons of rat spinal cord were evaluated. The effect of ASIC1a on the Ca2+ ion concentration in the dorsal horn neurons of rat spinal cord was measured by the intracellular calcium ([Ca2+]i) intensity. The effect of ASIC1a on the p38/mitogen-activated protein kinase (MAPK) signaling pathway was also determined. ASIC1a was significantly upregulated in the CP rat model as compared with control rats. Acid-induced ASIC1a expression increased [Ca2+]i intensity in the dorsal horn neurons of rat spinal cord. ASIC1a also increased the levels of neurogenic inflammation-related factors and p-p38 expression in the acid-treated dorsal horn neurons. Notably, ASIC1a knockdown significantly decreased the expression of pro-inflammatory cytokines. Furthermore, the levels of p-p38 and pro-inflammatory cytokines in acid-treated dorsal horn neurons were significantly decreased in the presence of PcTx-1, BAPTA-AM, or SB203580. Our results showed that ASIC1a may contribute to the symptom of pain in patients with CP, at least partially, by regulating the p38/MAPK signaling pathway.
Acid Sensing Ion Channel Blockers/pharmacology*
;
Acid Sensing Ion Channels/genetics*
;
Animals
;
Calcium/metabolism*
;
Chelating Agents/pharmacology*
;
Chronic Disease
;
Cytokines/metabolism*
;
Disease Models, Animal
;
Egtazic Acid/pharmacology*
;
Gene Knockdown Techniques
;
Imidazoles/pharmacology*
;
Inflammation/metabolism*
;
MAP Kinase Signaling System/genetics*
;
Male
;
Pain/genetics*
;
Peptides/pharmacology*
;
Phosphorylation/drug effects*
;
Posterior Horn Cells/metabolism*
;
Prostatitis/complications*
;
Protein Kinase Inhibitors/pharmacology*
;
Pyridines/pharmacology*
;
Rats
;
Spider Venoms/pharmacology*
;
Up-Regulation
;
p38 Mitogen-Activated Protein Kinases/metabolism*
6.Analysis of the shelf life of chitosan stored in different types of packaging, using colorimetry and dentin microhardness.
Antonio Miranda da CRUZ-FILHO ; Angelo Rafael de Vito BORDIN ; Luis Eduardo SOUZA-FLAMINI ; Débora Fernandes da Costa GUEDES ; Paulo César SAQUY ; Ricardo Gariba SILVA ; Jesus Djalma PÉCORA
Restorative Dentistry & Endodontics 2017;42(2):87-94
OBJECTIVES: Chitosan has been widely investigated and used. However, the literature does not refer to the shelf life of this solution. This study evaluated, through the colorimetric titration technique and an analysis of dentin micro-hardness, the shelf life of 0.2% chitosan solution. MATERIALS AND METHODS: Thirty human canines were sectioned, and specimens were obtained from the second and third slices, from cemento-enamel junction to the apex. A 0.2% chitosan solution was prepared and distributed in 3 identical glass bottles (v1, v2, and v3) and 3 plastic bottles (p1, p2, and p3). At 0, 7, 15, 30, 45, 60, 90, 120, 150, and 180 days, the specimens were immersed in each solution for 5 minutes (n = 3 each). The chelating effect of the solution was assessed by micro-hardness and colorimetric analysis of the dentin specimens. 17% EDTA and distilled water were used as controls. Data were analyzed statistically by two-way and Tukey-Kramer multiple comparison (α = 0.05). RESULTS: There was no statistically significant difference among the solutions with respect to the study time (p = 0.113) and micro-hardness/time interaction (p = 0.329). Chitosan solutions and EDTA reduced the micro-hardness in a similar manner and differed significantly from the control group (p < 0.001). Chitosan solutions chelated calcium ions throughout the entire experiment. CONCLUSIONS: Regardless of the storage form, chitosan demonstrates a chelating property for a minimum period of 6 months.
Calcium
;
Chelating Agents
;
Chitosan*
;
Colorimetry*
;
Dentin*
;
Edetic Acid
;
Glass
;
Humans
;
Ions
;
Plastics
;
Product Packaging*
;
Water
7.Comparison of MPure-12 Automatic Nucleic Acid Purification and Chelex-100 Method.
Xiang SHENG ; Min LI ; Ya Li WANG ; Yu Ling CHEN ; Yuan LIN ; Zhen Min ZHAO ; Ting Zhi QUE
Journal of Forensic Medicine 2017;33(2):168-170
OBJECTIVESTo explore the forensic application value of MPure-12 automatic nucleic acid purification (MPure-12 Method) for DNA extraction by extracting and typing DNA from bloodstains and various kinds of biological samples with different DNA contents.
METHODSNine types of biological samples, such as bloodstains, semen stains, and saliva were collected. DNA were extracted using MPure-12 method and Chelex-100 method, followed by PCR amplification and electrophoresis for obtaining STR-profiles.
RESULTSThe samples such as hair root, chutty, butt, muscular tissue, saliva stain, bloodstain and semen stain were typed successfully by MPure-12 method. Partial alleles were lacked in the samples of saliva, and the genotyping of contact swabs was unsatisfactory. Additional, all of the bloodstains (20 μL, 15 μL, 10 μL, 5 μL, 1 μL) showed good typing results using Chelex-100 method. But the loss of alleles occurred in 1 μL blood volume by MPure-12 method.
CONCLUSIONSMPure-12 method is suitable for DNA extraction of a certain concentration blood samples.Chelex-100 method may be better for the extraction of trace blood samples.This instrument used in nucleic acid extraction has the advantages of simplicity of operator, rapidity, high extraction efficiency, high rate of reportable STR-profiles and lower man-made pollution.
Alleles ; Blood Stains ; Chelating Agents ; DNA/isolation & purification* ; DNA Fingerprinting ; Forensic Medicine/methods* ; Genotype ; Humans ; Male ; Polymerase Chain Reaction/methods* ; Polystyrenes ; Polyvinyls ; Resins, Synthetic ; Saliva ; Semen/chemistry*
8.Evaluation of mercury exposure level, clinical diagnosis and treatment for mercury intoxication.
Byeong Jin YE ; Byoung Gwon KIM ; Man Joong JEON ; Se Yeong KIM ; Hawn Cheol KIM ; Tae Won JANG ; Hong Jae CHAE ; Won Jun CHOI ; Mi Na HA ; Young Seoub HONG
Annals of Occupational and Environmental Medicine 2016;28(1):5-
Mercury occurs in various chemical forms, and it is different to health effects according to chemical forms. In consideration of the point, the evaluation of the mercury exposure to human distinguished from occupational and environmental exposure. With strict to manage occupational exposure in factory, it is declined mercury intoxication cases by metallic and inorganic mercury inhalation to occupational exposure. It is increasing to importance in environmental exposure and public health. The focus on the health impact of exposure to mercury is more on chronic, low or moderate grade exposure—albeit a topic of great controversy—, not high concentration exposure by methylmercury, which caused Minamata disease. Recently, the issue of mercury toxicity according to the mercury exposure level, health effects as well as the determination of what mercury levels affect health are in the spotlight and under active discussion. Evaluating the health effects and Biomarker of mercury exposure and establishing diagnosis and treatment standards are very difficult. It can implement that evaluating mercury exposure level for diagnosis by a provocation test uses chelating agent and conducting to appropriate therapy according to the result. but, indications for the therapy of chelating agents with mercury exposure have not yet been fully established. The therapy to symptomatic patients with mercury poisoning is chelating agents, combination therapy with chelating agents, plasma exchange, hemodialysis, plasmapheresis. But the further evaluations are necessary for the effects and side effects with each therapy.
Chelating Agents
;
Diagnosis*
;
Environmental Exposure
;
Humans
;
Inhalation
;
Mercury Poisoning
;
Mercury Poisoning, Nervous System
;
Occupational Exposure
;
Plasma Exchange
;
Plasmapheresis
;
Public Health
;
Renal Dialysis
9.Efficacy and safety of deferasirox in aplastic anemia patients with iron overload: a single arm, multi-center,prospective study in China.
Jun SHI ; Hong CHANG ; Li ZHANG ; Yinqi SHAO ; Neng NIE ; Jing ZHANG ; Jinbo HUANG ; Li ZHANG ; Xudong TANG ; Richeng QUAN ; Chunmei ZHENG ; Haiyan XIAO ; Dengming HU ; Lingyan HU ; Feng LIU ; Yongming ZHOU ; Yizhou ZHENG ; Fengkui ZHANG
Chinese Journal of Hematology 2016;37(1):1-6
OBJECTIVETo explore the efficacy and safety of deferasirox in aplastic anemia (AA)patients with iron overload.
METHODSA single arm, multi- center, prospective, open- label study was conducted to evaluate absolute change in serum ferritin (SF)from baseline to 12 months of deferasirox administration, initially at a dose of 20 mg·kg(-1)·d(-1), and the safety in 64 AA patients with iron overload.
RESULTSAll patients started their deferasirox treatment with a daily dose of 20 mg · kg(-1) ·d(-1). The mean actual dose was (18.6±3.60) mg · kg(-1)·d(-1). The median SF decreased from 4 924 (2 718- 6 765)μg/L at baseline (n=64) to 3 036 (1 474- 5 551)μg/L at 12 months (n=23) with the percentage change from baseline as 38%. A median SF decrease of 651 (126-2 125)μg/L was observed at the end of study in 23 patients who completed 12 months' treatment, the median SF level decreased by 1 167(580-4 806)μg/L [5 271(3 420-8 278)μg/L at baseline; 3 036(1 474-5 551)μg/L after 12 months' treatment; the percentage change from baseline as 42% ] after 12 months of deferasirox treatment. The most common adverse events (AEs) were increased serum creatinine levels (40.98%), gastrointestinal discomfort (40.98%), elevated liver transaminase (ALT: 21.31%; AST: 13.11%)and proteinuria (24.59%). The increased serum creatinine levels were reversible and non-progressive. Of 38 patients with concomitant cyclosporine use, 12(31.8%)patients had two consecutive values >ULN, 10(26.3%)patients had two consecutive values >1.33 baseline values, but only 1(2.6%)patient's serum creatinine increased more than 1.33 baseline values and exceeded ULN. For both AST and ALT, no patients experienced two post- baseline values >5 ×ULN or >10 × ULN during the whole study. In AA patients with low baseline PLT count (less than 50 × 10(9)/L), there was no decrease for median PLT level during 12 months' treatment period.
CONCLUSIONSAA patients with iron overload could achieve satisfactory efficacy of iron chelation by deferasirox treatment. The drug was well tolerated with a clinically manageable safety profile and no major adverse events.
Anemia, Aplastic ; drug therapy ; Benzoates ; therapeutic use ; Blood Transfusion ; China ; Ferritins ; blood ; Humans ; Iron ; blood ; Iron Chelating Agents ; therapeutic use ; Iron Overload ; drug therapy ; Liver ; Prospective Studies ; Triazoles ; therapeutic use
10.Use of deferasirox, an iron chelator, to overcome imatinib resistance of chronic myeloid leukemia cells.
Dae Sik KIM ; Yoo Jin NA ; Myoung Hee KANG ; Soo Young YOON ; Chul Won CHOI
The Korean Journal of Internal Medicine 2016;31(2):357-366
BACKGROUND/AIMS: The treatment of chronic myeloid leukemia (CML) has achieved impressive success since the development of the Bcr-Abl tyrosine kinase inhibitor, imatinib mesylate. Nevertheless, resistance to imatinib has been observed, and a substantial number of patients need alternative treatment strategies. METHODS: We have evaluated the effects of deferasirox, an orally active iron chelator, and imatinib on K562 and KU812 human CML cell lines. Imatinib-resistant CML cell lines were created by exposing cells to gradually increasing concentrations of imatinib. RESULTS: Co-treatment of cells with deferasirox and imatinib induced a synergistic dose-dependent inhibition of proliferation of both CML cell lines. Cell cycle analysis showed an accumulation of cells in the subG1 phase. Western blot analysis of apoptotic proteins showed that co-treatment with deferasirox and imatinib induced an increased expression of apoptotic proteins. These tendencies were clearly identified in imatinib-resistant CML cell lines. The results also showed that co-treatment with deferasirox and imatinib reduced the expression of BcrAbl, phosphorylated Bcr-Abl, nuclear factor-kappaB (NF-kappaB) and beta-catenin. CONCLUSIONS: We observed synergistic effects of deferasirox and imatinib on both imatinib-resistant and imatinib-sensitive cell lines. These effects were due to induction of apoptosis and cell cycle arrest by down-regulated expression of NF-kappaB and beta-catenin levels. Based on these results, we suggest that a combination treatment of deferasirox and imatinib could be considered as an alternative treatment option for imatinib-resistant CML.
Antineoplastic Agents/*pharmacology
;
Apoptosis/drug effects
;
Apoptosis Regulatory Proteins/metabolism
;
Benzoates/*pharmacology
;
Cell Proliferation/drug effects
;
Dose-Response Relationship, Drug
;
Drug Resistance, Neoplasm/*drug effects
;
G1 Phase Cell Cycle Checkpoints/drug effects
;
Humans
;
Imatinib Mesylate/*pharmacology
;
Iron Chelating Agents/*pharmacology
;
K562 Cells
;
Leukemia, Myelogenous, Chronic, BCR-ABL Positive/*drug therapy/metabolism
;
Protein Kinase Inhibitors/*pharmacology
;
Signal Transduction/drug effects
;
Triazoles/*pharmacology


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