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Howlett B, Todd J, Willcox B, Rader R, Nelson W, Gee M, Schmidlin F, Read S, Walker M, Gibson D, Davidson M. Using non-bee and bee pollinator-plant species interactions to design diverse plantings benefiting crop pollination services. ADV ECOL RES 2021. [DOI: 10.1016/bs.aecr.2020.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Karmakar S, Kostrhunova H, Ctvrtlikova T, Novohradsky V, Gibson D, Brabec V. Platinum(IV)-Estramustine Multiaction Prodrugs Are Effective Antiproliferative Agents against Prostate Cancer Cells. J Med Chem 2020; 63:13861-13877. [PMID: 33175515 DOI: 10.1021/acs.jmedchem.0c01400] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Herein, we describe the synthesis, characterization, and biological properties of Pt(IV) derivatives of cisplatin with estramustine at the first axial position, which is known to disrupt the microtubule assembly and act as an androgen antagonist, and varying the second axial position using an innocent ligand (acetate or hydroxyl) to prepare dual-action and triple-action prodrugs with known inhibitors of histone deacetylase, cyclooxygenase, and pyruvate dehydrogenase kinase. We demonstrate superior antiproliferative activity at submicromolar concentrations of the prodrugs against a panel of cancer cell lines, particularly against prostate cancer cell lines. The results obtained in this study exemplify the complex mode of action of "multiaction" Pt(IV) prodrugs. Interestingly, changing the second axial ligand in the Pt-estramustine complex has a significant effect on the mode of action, suggesting that all three components of the Pt(IV) prodrugs (platinum moiety and axial ligands) contribute to the killing of cells and not just one dominant component.
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Khattib D, Ishan M, Karmakar S, Kostrhunova H, Brabec V, Gibson D. Oxidation of cis-Diamminediacetato Pt II with Hydrogen Peroxide Can Give Rise to Two Isomeric Pt IV Products. Chemistry 2020; 26:9475-9480. [PMID: 32428256 DOI: 10.1002/chem.202001472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/08/2020] [Indexed: 11/12/2022]
Abstract
The oxidation of cis-[Pt(NH3 )2 (OAc)2 ] with H2 O2 yields a mixture of two isomers: ctc-[Pt(NH3 )2 (OH)2 (OAc)2 ] and ctc-[Pt(NH3 )2 (OH)(OAc)(OH)(OAc)]. Following modification with 4-phenylbutyric (PhB) anhydride, two isomers were separated and characterized; the symmetric ctc-[Pt(NH3 )2 (PhB)2 (OAc)2 ] (1) and the nonsymmetric ctc-[Pt(NH3 )2 (PhB)(OAc)(PhB)(OAc)] (2). They differ in their log P values and despite having similar cellular uptake and similar DNA platination levels, the symmetric ctc-[Pt(NH3 )2 (OH)2 (OAc)2 ] is more than 4-fold more potent than the nonsymmetric isomer in a panel of 4 cancer cell lines.
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Whyte A, Gibson D. Imaging of sleep-disordered breathing in adults. Clin Radiol 2020; 75:960.e1-960.e16. [PMID: 32620255 DOI: 10.1016/j.crad.2020.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/15/2020] [Indexed: 10/24/2022]
Abstract
Sleep-disordered breathing (SDB) is a term that includes several chronic conditions in which partial or complete cessation of breathing occurs multiple times throughout the night. Central sleep apnoea (CSA) is uncommon and defined by the episodic cessation of airflow without respiratory effort. Lesions involving the respiratory centre in the brainstem or the origin of the phrenic nerve from the mid-cervical cord are the commonest structural causes of CSA; magnetic resonance imaging (MRI) will demonstrate the lesion and frequently suggest the likely aetiology. In contrast, obstructive sleep apnoea (OSA) is defined as upper airway obstruction despite ongoing respiratory effort. Repetitive episodes of narrowing or closure of the upper airway are the predominant cause leading to snoring and OSA, respectively. OSA affects 33-40% of the adult population and is associated with multiple adverse health consequences, including a significantly increased risk of serious morbidity and mortality. The incidence is increasing proportionally to the worldwide rise in obesity. Imaging, performed primarily without the involvement of radiologists, has been integral to understanding the anatomical basis of SDB and especially OSA. This article will review the pathophysiology, imaging findings, and sequelae of these common conditions. The role of imaging both in suggesting the incidental diagnoses of SDB and in the investigation of these conditions when the diagnosis is suspected or has been established are also discussed.
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Christodoulidou M, Lal S, Ramachandran N, Burden S, Gibson D, Alnajjar H, Mitra A, Richards T, Muneer A. The use of body composition parameters as predictors of metastatic disease and prognostic indicators in penile cancer – a eUROGEN centre study. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)32759-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Ramanna H, Lloret JL, Zahwe F, Porterfield C, Trines S, Djajadisastra I, Gibson D, Gururaj A, Alizadeh Dehnavi R, Raine D, James S, Razak E, Oommen S, Tao C, Olson N. P1383Procedural differences during de novo paroxysmal atrial fibrillation ablation with a contact force-sensing ablation catheter between Europe and U.S. Europace 2020. [DOI: 10.1093/europace/euaa162.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Although pulmonary vein isolation (PVI) is considered the standard approach of atrial fibrillation ablation worldwide, procedural practice during the ablation varies by geographical region. Using the same magnetic sensor enabled contact force-sensing ablation catheter for the treatment of de novo paroxysmal atrial fibrillation, a comparison of procedural detail between Europe and U.S operators can provide insights into geographic specific clinical practices.
Purpose
To characterize and compare procedural differences during paroxysmal atrial fibrillation ablation performed with a magnetic sensor enabled contact force-sensing catheter across European and U.S. centers.
Methods
Procedural data were prospectively collected in clinical cases performed with a new magnetic sensor enabled, contact force ablation catheter within the first 6 months of use at participating centers in Europe and the U.S. Procedure time, PVI time, PVI confirmation method, fluoroscopy usage and lesion delivery parameters were analyzed based on geographies.
Results
A total of 131 cases across 35 centers in 11 European countries, and 95 cases across 26 U.S. centers were analyzed. Target geometry was created with the ablation catheter in 94 out of 131 (71.8%) European cases, while only 5 out of 95 U.S. cases (5.3%) reported the use of the ablation catheter for model creation. Although a steerable sheath (64.1% and 67.3%) was commonly used with the ablation catheter in both geographies, difference in the utilization of bidirectional contact force catheter (52.7% and 90.5%) and the automated lesion marking module (76.3% and 81.1%) were observed in European and U.S. cases, respectively. The use of adenosine or isoproterenol to confirm PVI was reported in 25% and 64% of the European and U.S. cases. Average waiting periods were 18.2 minutes and 26.5 minutes from reported European and U.S. cases. Total procedural time, mapping time, and fluoroscopy time were similar between European and U.S. cases. (Table). First pass PVI were 66.4% and 72.6% for European and U.S. cases, respectively.
Conclusion
Total procedural time and RF time were similar between European and U.S. cases during de novo paroxysmal atrial fibrillation ablation using the same ablation catheter. Differences in workflow including the use of a mapping catheter for geometry creation and waiting period were observed between the two geographies.
Summary of procedural details De novo PAF N Procedural time(min) Mapping time (min) PVI time (min) Total RF time (min) Fluoro time( min) Europe 131 144.0 ± 56.9 16.6 ± 17.1 69.8 ± 35.0 33.2 ± 15.6 11.6 ± 10.1 U.S. 95 137.6 ± 64.8 18.1 ± 23.5 58.8 ± 31.5 32.3 ± 22.2 12.0 ± 15.8
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Ramanna H, Lloret JL, Zahwe F, Porterfield C, Trines S, Djajadisastra I, Gibson D, Gururaj A, Alizadeh Dehnavi R, Raine D, James S, Razak E, Oommen S, Tao C, Olson N. P981Comparison of automark utilization and lesion metric target during paroxysmal atrial fibrillation ablation with a contact force-sensing ablation catheter: European and U.S. multicenter Experiences. Europace 2020. [DOI: 10.1093/europace/euaa162.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Accurate delivery of transmural lesion is associated with improved durability of pulmonary vein isolation and reduced reconduction. Lesion quality depends on multiple parameters such as radiofrequency power, tissue-catheter contact, duration of energy application, and catheter tip temperature. Consequently, energy delivery parameters vary based on individual operators’ preferences and procedural needs.
Purpose
To characterize and compare the utilization of automated lesion marking feature and lesion delivery parameters used during paroxysmal atrial fibrillation ablation performed with a magnetic sensor enabled contact force-sensing catheter across European and U.S. centers.
Methods
Procedural data were prospectively collected in clinical cases performed with a new magnetic sensor enabled, contact force ablation catheter within the first 6 months of use at participating centers in Europe and the U.S. Use of bidirectional CF catheters, steerable sheaths, automated lesion marking software and associated lesion delivery parameters during paroxysmal atrial fibrillation ablation were evaluated.
Results
A total of 149 cases across 37 centers in 11 European countries, and 112 cases across 31 U.S. centers were analyzed. A bidirectional contact force catheter (56.4% and 90.2%), a steerable sheath (65.8% and 69.6%), and the automated lesion marking module (77.9% and 90.2%) were used in most European and U.S. cases, respectively. The most commonly reported energy delivery parameters were: lesion index (LSI), Force-Time Integral (FTI), and time from European cases; LSI, average force, and FTI for U.S. cases (Table). Target LSI values were recorded for 126 cases in Europe and 34 in the U.S, ranging from 3 to 6. In anterior/roof segments, most common LSI target values for anterior/roof and posterior/inferior segments were 6 (42.9%) and 5 (51.2%) in Europe, and 5.5 (44.1%) and 5 (54.5%) in the U.S. PVI was confirmed with an average of 20.3 minutes waiting period (69.1%) for European cases and exit block (57.1%) in U.S. cases. First pass PVI were 67.1% and 74.4% for European and U.S. cases, respectively.
Conclusion
Energy delivery parameters and PVI confirmation method varied considerably by geography during paroxysmal atrial fibrillation ablation using the magnetic sensor enabled, contact force ablation catheter. Further study on efficacy implication on these differences in practice should be examined.
Energy delivery parameters used Paroxysmal AF N LSI FTI Time Imp Drop Avg Force Other N/A Europe 149 44.0 % 13.4 % 7.0 % 6.0 % 2.4 % 1.0 % 26.2 % U.S. 112 31.2% 17.9 % 6.2 % 8.0 % 23.2 % 11.7 % 1.8 % Energy delivery parameters used in paroxysmal AF ablation in Europe and U.S.
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Babu T, Sarkar A, Karmakar S, Schmidt C, Gibson D. Multiaction Pt(IV) Carbamate Complexes Can Codeliver Pt(II) Drugs and Amine Containing Bioactive Molecules. Inorg Chem 2020; 59:5182-5193. [PMID: 32207294 DOI: 10.1021/acs.inorgchem.0c00445] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Multiaction Pt(IV) prodrugs can overcome resistance associated with the FDA approved Pt(II) drugs like cisplatin. Intracellular reduction of the octahedral Pt(IV) derivatives of cisplatin releases cisplatin and the two axial ligands. When the released axial ligands act synergistically with cisplatin to kill the cancer cells, we have multiaction prodrugs. Most Pt(IV) multiaction prodrugs have bioactive ligands possessing a carboxylate that is conjugated to the Pt(IV) because breaking the Pt(IV)-ligand bond releases the active moiety. As many drugs that act synergistically with cisplatin do not have carboxylates, a major challenge is to prepare multiaction Pt(IV) complexes with drugs that have amino groups or hydroxyl groups such that following reduction, the drugs are released in their active form. Our objective was to prepare multiaction Pt(IV) prodrugs that release bioactive molecules having amino groups. Because we cannot conjugate amino groups to the axial position of Pt(IV), we developed a novel and efficient approach for the synthesis of Pt(IV)-carbamato complexes and demonstrated that following reduction of the Pt(IV), the released carbamates undergo rapid decarboxylation, releasing the free amine, as in the case of the PARP-1 inhibitor 3-aminobenzamide and the amino derivative of the HDAC inhibitor SAHA. Pt(IV)-carbamato complexes are stable in cell culture medium and are reduced by ascorbate. They are reduced slower than their carboxylato and carbonato analogues. We believe that this approach paves the way for preparing novel classes of multiaction Pt(IV) prodrugs with amino containing bioactive molecules that up to now were not accessible.
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Karges J, Yempala T, Tharaud M, Gibson D, Gasser G. A Multi-action and Multi-target Ru II -Pt IV Conjugate Combining Cancer-Activated Chemotherapy and Photodynamic Therapy to Overcome Drug Resistant Cancers. Angew Chem Int Ed Engl 2020; 59:7069-7075. [PMID: 32017379 DOI: 10.1002/anie.201916400] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/28/2020] [Indexed: 12/21/2022]
Abstract
PtII complexes are commonly used to treat cancer. To reduce their side effects and improve their pharmacological properties, PtIV complexes are being developed as prodrug candidates that are activated by reduction in cancer cells. Concomitantly, RuII polypyridine complexes have gained much attention as photosensitizers for use in photodynamic therapy due to their attractive characteristics. In this article, a novel PtIV -RuII conjugate, which combines cancer activated chemotherapy with PDT, is presented. Upon entering the cancer cell, the PtIV centre is reduced to PtII and the axial ligands including the RuII complex and phenylbutyrate are released. As each component has its individual targets, the conjugate exerts a multi-target and multi-action effect with (photo-)cytotoxicity values upon irradiation up to 595 nm in the low nanomolar range in various (drug resistant) 2D monolayer cancer cells and 3D multicellular tumour spheroids.
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Karges J, Yempala T, Tharaud M, Gibson D, Gasser G. A Multi‐action and Multi‐target Ru
II
–Pt
IV
Conjugate Combining Cancer‐Activated Chemotherapy and Photodynamic Therapy to Overcome Drug Resistant Cancers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201916400] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Yempala T, Babu T, Gibson D, Cassels BK. Dibenzofuran annulated 1-azepines: Synthesis and cytotoxicity. SYNTHETIC COMMUN 2019. [DOI: 10.1080/00397911.2019.1703001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Karmakar S, Poetsch I, Kowol CR, Heffeter P, Gibson D. Synthesis and Cytotoxicity of Water-Soluble Dual- and Triple-Action Satraplatin Derivatives: Replacement of Equatorial Chlorides of Satraplatin by Acetates. Inorg Chem 2019; 58:16676-16688. [PMID: 31790216 DOI: 10.1021/acs.inorgchem.9b02796] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pt(II) complexes, such as cisplatin and oxaliplatin, are in widespread use as anticancer drugs. Their use is limited by the toxic side effects and the ability of tumors to develop resistance to the drugs. A popular approach to overcome these drawbacks is to use their kinetically inert octahedral Pt(IV) derivatives that act as prodrugs. The most successful Pt(IV) complex in clinical trials to date is satraplatin, cct-[Pt(NH3)(c-hexylamine)Cl2(OAc)2], that upon cellular reduction releases the cytotoxic cis-[Pt(NH3)(c-hexylamine)Cl2]. In an attempt to obtain water-soluble and more effective cytotoxic Pt(IV) complexes, we prepared a series of dual- and triple-action satraplatin analogues, where the equatorial chlorido ligands were replaced with acetates and the axial ligands include innocent and bioactive ligands. Replacement of the chlorides with acetates enhanced the water solubility of the compounds and, with one exception, all of the compounds were very stable in buffer. In general, compounds with one or two axial hydroxido ligands were reduced by ascorbate significantly more quickly than compounds with two axial carboxylates. While replacement of the chlorides with acetates in satraplatin led to a reduction in cytotoxicity, the dual- and triple-action analogues with equatorial acetates had low- to sub-micromolar IC50 values in a panel of eight cancer cells. The triple-action compound cct-[Pt(NH3)(c-hexylamine)(OAc)2(PhB)(DCA)] was active in all cell lines, causing DNA damage that induced cell cycle inhibition and apoptosis. Its good activity against CT26 cells in vitro translated into good in vivo efficacy against the CT26 allograft, an in vivo model with intrinsic satraplatin resistance. This indicates that multiaction Pt(IV) derivatives of diamine dicarboxylates are interesting anticancer drug candidates.
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Yempala T, Babu T, Karmakar S, Nemirovski A, Ishan M, Gandin V, Gibson D. Expanding the Arsenal of Pt IV Anticancer Agents: Multi-action Pt IV Anticancer Agents with Bioactive Ligands Possessing a Hydroxy Functional Group. Angew Chem Int Ed Engl 2019; 58:18218-18223. [PMID: 31599054 DOI: 10.1002/anie.201910014] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Indexed: 12/16/2022]
Abstract
Most multi-action PtIV prodrugs have bioactive ligands containing carboxylates. This is probably due to the ease of carboxylating the OH axial ligands and because following reduction, the active drug is released. A major challenge is to expand the arsenal of bioactive ligands to include those without carboxylates. We describe a general approach for synthesis of PtIV prodrugs that release drugs with OH groups. We linked the OH groups of gemcitabine (Gem), paclitaxel (Tax), and estramustine (EM) to the PtIV derivative of cisplatin by a carbonate bridge. Following reduction, the axial ligands lost CO2 , rapidly generating the active drugs. In contrast, succinate-linked drugs did not readily release the free drugs. The carbonate-bridged ctc-[Pt(NH3 )2 (PhB)(Gem-Carb)Cl2 ] was significantly more cytotoxic than the succinate-bridged ctc-[Pt(NH3 )2 (PhB)(Gem-Suc)Cl2 ], and more potent and less toxic than gemcitabine, cisplatin, and co-administration of cisplatin and gemcitabine.
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Yempala T, Babu T, Karmakar S, Nemirovski A, Ishan M, Gandin V, Gibson D. Expanding the Arsenal of Pt
IV
Anticancer Agents: Multi‐action Pt
IV
Anticancer Agents with Bioactive Ligands Possessing a Hydroxy Functional Group. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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40
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Kostrhunova H, Zajac J, Novohradsky V, Kasparkova J, Malina J, Aldrich-Wright JR, Petruzzella E, Sirota R, Gibson D, Brabec V. A Subset of New Platinum Antitumor Agents Kills Cells by a Multimodal Mechanism of Action Also Involving Changes in the Organization of the Microtubule Cytoskeleton. J Med Chem 2019; 62:5176-5190. [PMID: 31030506 DOI: 10.1021/acs.jmedchem.9b00489] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The substitution inert platinum agent [Pt(1 S,2 S-diaminocyclohexane)(5,6-dimethyl-1,10-phenanthroline)]2+ (56MeSS, 5) is a potent cytotoxic metallodrug. In contrast to conventional cisplatin or oxaliplatin, the mechanism of action (MoA) of 5 is fundamentally different. However, details of the mechanism by which the 5,6-dimethyl-1,10-phenanthroline ligand contributes to the cytotoxicity of 5 and its derivatives have not been sufficiently clarified so far. Here, we show that 5 and its Pt(IV) derivatives exhibit an intriguing potency in the triple-negative breast cancer cells MDA-MB-231. Moreover, we show that the Pt(IV) derivatives of 5 act by multimodal MoA resulting in the global biological effects, that is, they damage nuclear DNA, reduce the mitochondrial membrane potential, induce the epigenetic processes, and last but not least, the data provide evidence that changes in the organization of cytoskeleton networks are functionally important for 5 and its derivatives, in contrast to clinically used platinum cytostatics, to kill cancer cells.
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Girgis D, Gibson D, Wood C, Subramaniam S, Bobinskas A. Radiographic study to assess the reliability of the gillies approach for biopsy of the superficial temporal artery. Int J Oral Maxillofac Surg 2019. [DOI: 10.1016/j.ijom.2019.03.282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Babak MV, Zhi Y, Czarny B, Toh TB, Hooi L, Chow EKH, Ang WH, Gibson D, Pastorin G. Dual-Targeting Dual-Action Platinum(IV) Platform for Enhanced Anticancer Activity and Reduced Nephrotoxicity. Angew Chem Int Ed Engl 2019; 58:8109-8114. [PMID: 30945417 DOI: 10.1002/anie.201903112] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Indexed: 01/16/2023]
Abstract
A novel and highly efficient dual-targeting platform was designed to ensure targeted in vivo delivery of dual-action PtIV prodrugs. The dual targeting was established by liposomal encapsulation of PtIV complexes, thereby utilizing the enhanced permeability and retention (EPR) effect as the first stage of targeting to attain a high accumulation of the drug-loaded liposomes in the tumor. After the release of the PtIV prodrug inside cancer cells, a second stage of targeting directed a portion of the PtIV prodrugs to the mitochondria. Upon intracellular reduction, these PtIV prodrugs released two bioactive molecules, acting both on the mitochondrial and on the nuclear DNA. Our PtIV system showed excellent activity in vitro and in vivo, characterized by a cytotoxicity in a low micromolar range and complete tumor remission, respectively. Notably, marked in vivo activity was accompanied by reduced kidney toxicity, highlighting the unique therapeutic potential of our novel dual-targeting dual-action platform.
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Kostrhunova H, Petruzzella E, Gibson D, Kasparkova J, Brabec V. An Anticancer Pt IV Prodrug That Acts by Mechanisms Involving DNA Damage and Different Epigenetic Effects. Chemistry 2019; 25:5235-5245. [PMID: 30740808 DOI: 10.1002/chem.201805626] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 02/07/2019] [Indexed: 01/25/2023]
Abstract
Dual- or multi-action PtIV prodrugs represent a new generation of platinum anticancer drugs. The important property of these PtIV prodrugs is that their antitumor action combines several different mechanisms owing to the presence of biologically active axial ligands. This work describes the synthesis and some biological properties of a "triple-action" prodrug that releases in cancer cells cisplatin and two different epigenetically acting moieties, octanoate and phenylbutyrate. It is demonstrated, with the aid of modern methods of molecular and cellular biology and pharmacology, that the presence of three different functionalities in a single molecule of the PtIV prodrug results in a selective and high potency in tumor cells including those resistant to cisplatin [the IC50 values in the screened malignant cell lines ranged from as low as 9 nm (HCT-116) to 74 nm (MDA-MB-231)]. It is also demonstrated that cellular activation of the PtIV prodrug results in covalent modification of DNA through the release of the platinum moiety accompanied by inhibition of the activity of histone deacetylases caused by phenylbutyrate and by global hypermethylation of DNA by octanoate. Thus, the PtIV prodrug introduced in this study acts as a true "multi-action" prodrug, which is over two orders of magnitude more active than clinically used cisplatin, in both 2D monolayer culture and 3D spheroid cancer cells.
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Liu J, Gibson D, Stearne K, Dobbin SW. Skipping breakfast and non-high-density lipoprotein cholesterol level in school children: a preliminary analysis. Public Health 2019; 168:43-46. [PMID: 30685597 DOI: 10.1016/j.puhe.2018.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/16/2018] [Accepted: 12/10/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The objective of the study is to examine whether the increased levels of non-high-density lipoprotein cholesterol (non-HDL-c) are associated with skipping breakfast among school children. STUDY DESIGN A cross-sectional survey was conducted among 539 school children aged 8-12 years from the Niagara Region of Canada. METHODS Non-fasting finger blood was taken for total cholesterol (total-c) and HDL-c measurements. Non-HDL-c was calculated as the difference between total-c and HDL-c. The information of skipping breakfast in a week was obtained from a questionnaire, which was categorized into three groups, i.e., none, 1-3 times and 4 + times. Demographic information and other related variables were described by the three breakfast-skipping groups. RESULTS Approximately 44% of children (n = 182) reported skipping breakfast. There were significant differences between the three groups in the means of total-c, non-HDL-c, body mass index, waist circumference, proportions of overall health excellent, eating dinner with parent and skipping breakfast that affects learning (P < 0.05). The number of days of skipping breakfast was weakly correlated to the level of non-HDL-c (r = 0.145, P < 0.0001). Multiple regression results indicated that every one more time of skipping breakfast would increase approximately 0.05 mmol/L level of non-HDL-c (P < 0.01), on average, after adjusting for those aforementioned potential confounding variables. The adjusted mean levels of non-HDL-c were 2.77, 2.94 and 3.07 mmol/L for none, skipping 1-3 times and skipping 4 + times of breakfast, respectively; the mean differences between none and the other two groups were statistical significant (P < 0.05). CONCLUSION Non-HDL-c levels is positively associated with the number of skipping breakfast among school children, and further research is needed to confirm this relationship.
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Gibson TN, Beeput S, Gaspard J, George C, Gibson D, Jackson N, Leandre-Broome V, Palmer-Mitchell N, Alexis C, Bird-Compton J, Bodkyn C, Boyle R, McLean-Salmon S, Reece-Mills M, Quee-Brown CS, Allen U, Weitzman S, Blanchette V, Gupta S. Baseline characteristics and outcomes of children with cancer in the English-speaking Caribbean: A multinational retrospective cohort. Pediatr Blood Cancer 2018; 65:e27298. [PMID: 30094928 DOI: 10.1002/pbc.27298] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND English-speaking Caribbean (ESC) childhood cancer outcomes are unknown. PROCEDURE Through the SickKids-Caribbean Initiative (SCI), we established a multicenter childhood cancer database across seven centers in six ESC countries. Data managers entered patient demographics, disease, treatment, and outcome data. Data collection commenced in 2013, with retrospective collection to 2011 and subsequent prospective collection. RESULTS A total of 367 children were diagnosed between 2011 and 2015 with a median age of 5.7 years (interquartile range 2.9-10.6 years). One hundred thirty (35.4%) patients were diagnosed with leukemia, 30 (8.2%) with lymphoma, and 149 (40.6%) with solid tumors. A relative paucity of children with brain tumors was seen (N = 58, 15.8%). Two-year event-free survival (EFS) for the cohort was 48.5% ± 3.2%; 2-year overall survival (OS) was 55.1% ± 3.1%. Children with acute lymphoblastic leukemia (ALL) and Wilms tumor (WT) experienced better 2-year EFS (62.1% ± 6.4% and 66.7% ± 10.1%), while dismal outcomes were seen in children with acute myeloid leukemia (AML; 22.7 ± 9.6%), rhabdomyosarcoma (21.0% ± 17.0%), and medulloblastoma (21.4% ± 17.8%). Of 108 deaths with known cause, 58 (53.7%) were attributed to disease and 50 (46.3%) to treatment complications. Death within 60 days of diagnosis was relatively common in acute leukemia [13/98 (13.3%) ALL, 8/26 (30.8%) AML]. Despite this, traditional prognosticators adversely impacted outcome in ALL, including higher age, higher white blood cell count, and T-cell lineage. CONCLUSIONS ESC childhood cancer outcomes are significantly inferior to high-income country outcomes. Based on these data, interventions for improving supportive care and modifying treatment protocols are under way. Continued data collection will allow evaluation of interventions and ensure maximal outcome improvements.
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Gibson D. Multi-action Pt(IV) anticancer agents; do we understand how they work? J Inorg Biochem 2018; 191:77-84. [PMID: 30471522 DOI: 10.1016/j.jinorgbio.2018.11.008] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/12/2018] [Accepted: 11/13/2018] [Indexed: 12/12/2022]
Abstract
Pt(IV) complexes act as prodrugs that are activated inside cancer cells releasing cytotoxic Pt(II) drugs such as cisplatin as well as two axial ligands. These ligands can be used to confer favorable pharmacological properties to the prodrug. They can be innocent spectators, targeting agents or bioactive moieties. When the ligands are bioactive moieties such as enzyme inhibitors or antiproliferative agents, the prodrug attacks several cellular targets at the same time acting as a multi-action prodrug. These compounds are very potent and often overcome resistance to cisplatin. Despite solid rationalization and careful design, often there is no correlation between the ability of the bioactive ligand to inhibit the target enzyme and the cytotoxicity. This might be because most bioactive ligands affect several cellular functions and not only the ones they were designed to inhibit. Thus, even "dual action" prodrugs might in reality be multi-action prodrugs. This class of multi-action Pt(IV) prodrugs seems to have great potential in the attempts to overcome resistance.
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Birney R, Steinlechner J, Tornasi Z, MacFoy S, Vine D, Bell AS, Gibson D, Hough J, Rowan S, Sortais P, Sproules S, Tait S, Martin IW, Reid S. Amorphous Silicon with Extremely Low Absorption: Beating Thermal Noise in Gravitational Astronomy. PHYSICAL REVIEW LETTERS 2018; 121:191101. [PMID: 30468587 DOI: 10.1103/physrevlett.121.191101] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/23/2018] [Indexed: 06/09/2023]
Abstract
Amorphous silicon has ideal properties for many applications in fundamental research and industry. However, the optical absorption is often unacceptably high, particularly for gravitational-wave detection. We report a novel ion-beam deposition method for fabricating amorphous silicon with unprecedentedly low unpaired electron-spin density and optical absorption, the spin limit on absorption being surpassed for the first time. At low unpaired electron density, the absorption is no longer correlated with electron spins, but with the electronic mobility gap. Compared to standard ion-beam deposition, the absorption at 1550 nm is lower by a factor of ≈100. This breakthrough shows that amorphous silicon could be exploited as an extreme performance optical coating in near-infrared applications, and it represents an important proof of concept for future gravitational-wave detectors.
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Riecke TV, Leach AG, Gibson D, Sedinger JS. Parameterizing the robust design in the BUGS language: Lifetime carry‐over effects of environmental conditions during growth on a long‐lived bird. Methods Ecol Evol 2018. [DOI: 10.1111/2041-210x.13065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Tao R, Hasan SA, Wang HZ, Zhou J, Luo JT, McHale G, Gibson D, Canyelles-Pericas P, Cooke MD, Wood D, Liu Y, Wu Q, Ng WP, Franke T, Fu YQ. Bimorph material/structure designs for high sensitivity flexible surface acoustic wave temperature sensors. Sci Rep 2018; 8:9052. [PMID: 29899347 PMCID: PMC5998018 DOI: 10.1038/s41598-018-27324-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 05/29/2018] [Indexed: 11/09/2022] Open
Abstract
A fundamental challenge for surface acoustic wave (SAW) temperature sensors is the detection of small temperature changes on non-planar, often curved, surfaces. In this work, we present a new design methodology for SAW devices based on flexible substrate and bimorph material/structures, which can maximize the temperature coefficient of frequency (TCF). We performed finite element analysis simulations and obtained theoretical TCF values for SAW sensors made of ZnO thin films (~5 μm thick) coated aluminum (Al) foil and Al plate substrates with thicknesses varied from 1 to 1600 μm. Based on the simulation results, SAW devices with selected Al foil or plate thicknesses were fabricated. The experimentally measured TCF values were in excellent agreements with the simulation results. A normalized wavelength parameter (e.g., the ratio between wavelength and sample thickness, λ/h) was applied to successfully describe changes in the TCF values, and the TCF readings of the ZnO/Al SAW devices showed dramatic increases when the normalized wavelength λ/h was larger than 1. Using this design approach, we obtained the highest reported TCF value of −760 ppm/K for a SAW device made of ZnO thin film coated on Al foils (50 μm thick), thereby enabling low cost temperature sensor applications to be realized on flexible substrates.
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Petruzzella E, Sirota R, Solazzo I, Gandin V, Gibson D. Triple action Pt(iv) derivatives of cisplatin: a new class of potent anticancer agents that overcome resistance. Chem Sci 2018; 9:4299-4307. [PMID: 29780561 PMCID: PMC5944384 DOI: 10.1039/c8sc00428e] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 04/07/2018] [Indexed: 01/11/2023] Open
Abstract
A series of triple action Pt(iv) prodrugs was designed to test the hypothesis that multi-action compounds, where each bioactive moiety intervenes in several cellular processes, might be more effective than a single agent at killing cancer cells. In particular, "triple action" Pt(iv) derivatives of cisplatin, where the axial ligands are inhibitors of cyclooxygenase (COXi), histone deacetylase (HDACi) or pyruvate dehydrogenase kinase (PDKi) were developed. All compounds, ctc-[Pt(NH3)2(COXi)(PDKi)Cl2], ctc-[Pt(NH3)2(COXi)(HDACi)Cl2] and ctc-[Pt(NH3)2(HDACi)(PDKi)Cl2], where COXi = aspirin or ibuprofen, PDKi = dichloroacetate and HDACi = valproate or phenylbutyrate, were significantly more cytotoxic than cisplatin against all cell lines of an in-house panel of human cancer cells. They were particularly effective against thyroid and pancreatic cancer cells in monolayer cytotoxicity tests. Remarkably, in 3D spheroid cancer cell cultures, some triple action compounds showed an antitumor potency up to 50-fold higher than cisplatin against a KRAS mutated pancreatic cancer cell line (PSN-1 cells). Standard biochemical assays classically employed to explore structure activity relationships of platinum drugs, such as cellular uptake and binding to potential biological targets (DNA, HDAC, mitochondria, and COX), do not provide linear correlations with the overall cytotoxicity data. We observed a preferential induction of ROS production and of an anti-mitochondrial effect in cancer cells compared to rapidly dividing non-cancerous cells. Thus, we propose that these new triple action Pt(iv) derivatives of cisplatin are a novel and interesting class of potent and selective cytotoxic agents.
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