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Graw N, Ruth PN, Ernemann T, Herbst-Irmer R, Stalke D. Indium Kα radiation from a MetalJet X-ray source: the long way to a successful charge-density investigation. J Appl Crystallogr 2023; 56:1315-1321. [PMID: 37791365 PMCID: PMC10543667 DOI: 10.1107/s1600576723007203] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 08/16/2023] [Indexed: 10/05/2023] Open
Abstract
The MetalJet X-ray source provides indium Kα radiation with a wavelength even shorter than Ag radiation. This paper reports on problematic spectral impurities and presents possible countermeasures so that collection of data with excellent quality up to a high resolution is possible. It is demonstrated that these data can be used in the refinement of a multipole model, the results of which are used for a topological analysis to assess the bonding situation in a sulfur ylide compound.
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Affiliation(s)
- Nico Graw
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, Göttingen, Lower Saxony 37077, Germany
| | - Paul Niklas Ruth
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, Göttingen, Lower Saxony 37077, Germany
| | - Tobias Ernemann
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, Göttingen, Lower Saxony 37077, Germany
| | - Regine Herbst-Irmer
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, Göttingen, Lower Saxony 37077, Germany
| | - Dietmar Stalke
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, Göttingen, Lower Saxony 37077, Germany
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Besnard C, Marie A, Sasidharan S, Harper RA, Shelton RM, Landini G, Korsunsky AM. Synchrotron X-ray Studies of the Structural and Functional Hierarchies in Mineralised Human Dental Enamel: A State-of-the-Art Review. Dent J (Basel) 2023; 11:98. [PMID: 37185477 PMCID: PMC10137518 DOI: 10.3390/dj11040098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/19/2023] [Accepted: 03/28/2023] [Indexed: 05/17/2023] Open
Abstract
Hard dental tissues possess a complex hierarchical structure that is particularly evident in enamel, the most mineralised substance in the human body. Its complex and interlinked organisation at the Ångstrom (crystal lattice), nano-, micro-, and macro-scales is the result of evolutionary optimisation for mechanical and functional performance: hardness and stiffness, fracture toughness, thermal, and chemical resistance. Understanding the physical-chemical-structural relationships at each scale requires the application of appropriately sensitive and resolving probes. Synchrotron X-ray techniques offer the possibility to progress significantly beyond the capabilities of conventional laboratory instruments, i.e., X-ray diffractometers, and electron and atomic force microscopes. The last few decades have witnessed the accumulation of results obtained from X-ray scattering (diffraction), spectroscopy (including polarisation analysis), and imaging (including ptychography and tomography). The current article presents a multi-disciplinary review of nearly 40 years of discoveries and advancements, primarily pertaining to the study of enamel and its demineralisation (caries), but also linked to the investigations of other mineralised tissues such as dentine, bone, etc. The modelling approaches informed by these observations are also overviewed. The strategic aim of the present review was to identify and evaluate prospective avenues for analysing dental tissues and developing treatments and prophylaxis for improved dental health.
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Affiliation(s)
- Cyril Besnard
- MBLEM, Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, Oxfordshire, UK
| | - Ali Marie
- MBLEM, Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, Oxfordshire, UK
| | - Sisini Sasidharan
- MBLEM, Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, Oxfordshire, UK
| | - Robert A. Harper
- School of Dentistry, University of Birmingham, 5 Mill Pool Way, Edgbaston, Birmingham B5 7EG, West Midlands, UK
| | - Richard M. Shelton
- School of Dentistry, University of Birmingham, 5 Mill Pool Way, Edgbaston, Birmingham B5 7EG, West Midlands, UK
| | - Gabriel Landini
- School of Dentistry, University of Birmingham, 5 Mill Pool Way, Edgbaston, Birmingham B5 7EG, West Midlands, UK
| | - Alexander M. Korsunsky
- MBLEM, Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, Oxfordshire, UK
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Girotti AW, Fahey JF, Korytowski W. Role of nitric oxide in hyper-aggressiveness of tumor cells that survive various anti-cancer therapies. Crit Rev Oncol Hematol 2022; 179:103805. [PMID: 36087851 DOI: 10.1016/j.critrevonc.2022.103805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/10/2022] [Accepted: 09/05/2022] [Indexed: 11/18/2022] Open
Abstract
Low level nitric oxide (NO) produced by inducible NO synthase (iNOS) in many malignant tumors is known to play a key role in the survival and proliferation of tumor cells. NO can also induce or augment resistance to anti-tumor treatments such as platinum-based chemotherapy (CT), ionizing radiotherapy (RT), and non-ionizing photodynamic therapy (PDT). In each of these treatments, tumor cells that survive the challenge may exhibit a striking increase in NO-dependent proliferative, migratory, and invasive aggressiveness compared with non-challenged controls. Moreover, NO from cells directly targeted by PDT can often stimulate aggressiveness in non- or poorly targeted bystander cells. Although NO-mediated resistance to many of these therapies is fairly-well recognized by now, the hyper-aggressiveness of surviving cells and bystander counterparts is not. We will focus on these negative aspects in this review, citing examples from the PDT, CT, and RT publications. Increased aggressiveness of cells that escape therapeutic elimination is a concern because it could enhance tumor progression and metastatic dissemination. Pharmacologic approaches for suppressing these negative responses will also be discussed, e.g., administering inhibitors of iNOS activity or iNOS expression as therapeutic adjuvants.
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Affiliation(s)
- Albert W Girotti
- Depatrment of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA.
| | - Jonathan F Fahey
- Department of Pathology, University of Colorado, Aurora, CO, USA
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Antoine C, Sahylí Ortega Pijeira M, Ricci-Junior E, Magalhães Rebelo Alencar L, Santos-Oliveira R. Graphene Quantum Dots as Bimodal Imaging Agent for X-Ray and Computed Tomography. Eur J Pharm Biopharm 2022; 179:74-78. [PMID: 36064083 DOI: 10.1016/j.ejpb.2022.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/09/2022] [Accepted: 08/29/2022] [Indexed: 11/04/2022]
Abstract
The urgency of new contrast agents, especially for X-Ray and Computed Tomography (CT) is increasing each day. Although both imaging modalities are the most routinely used imaging techniques, the availability of contrast agent is very limited. In this scenario, the use of graphene quantum dots (GQDs), a member of the graphene family, which has several characteristics, including low toxicity, good biocompatibility and physical-chemical properties, may represent an important application of this material. Thus, using X-Ray (conventional) and CT analysis was evaluated the applicability of GQDs as contrast agent for both imaging modalities. The results demonstrated that GQDs are able to attenuate X-Ray forming sharp imaging in both modalities. The data broaden the spectrum of GQDs use.
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Affiliation(s)
- Claudia Antoine
- Brazilian Nuclear Energy Commission, Nuclear Engineering Institute, Laboratory of Nanoradiopharmacy and Synthesis of New Radiopharmaceuticals, Rio de Janeiro 21941906, RJ, Brazil
| | - Martha Sahylí Ortega Pijeira
- Brazilian Nuclear Energy Commission, Nuclear Engineering Institute, Laboratory of Nanoradiopharmacy and Synthesis of New Radiopharmaceuticals, Rio de Janeiro 21941906, RJ, Brazil
| | - Eduardo Ricci-Junior
- Federal University of Rio de Janeiro, School of Pharmacy, Rio de Janeiro 21941900, RJ, Brazil
| | | | - Ralph Santos-Oliveira
- Brazilian Nuclear Energy Commission, Nuclear Engineering Institute, Laboratory of Nanoradiopharmacy and Synthesis of New Radiopharmaceuticals, Rio de Janeiro 21941906, RJ, Brazil; Rio de Janeiro State University, Laboratory of Radiopharmacy and Nanoradiopharmaceuticals, Rio de Janeiro 23070200, RJ, Brazil.
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Al-Harbi N, Sayyed M, Al-Hadeethi Y, Kumar A, Elsafi M, Mahmoud K, Khandaker MU, Bradley D. A novel CaO–K2O–Na2O–P2O5 glass systems for radiation shielding applications. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109645] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Feasibility of Monitoring Tumor Response by Tracking Nanoparticle-Labelled T Cells Using X-ray Fluorescence Imaging-A Numerical Study. Int J Mol Sci 2021; 22:ijms22168736. [PMID: 34445443 PMCID: PMC8395984 DOI: 10.3390/ijms22168736] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/28/2021] [Accepted: 08/10/2021] [Indexed: 12/18/2022] Open
Abstract
Immunotherapy has been a breakthrough in cancer treatment, yet only a subgroup of patients responds to these novel drugs. Parameters such as cytotoxic T-cell infiltration into the tumor have been proposed for the early evaluation and prediction of therapeutic response, demanded for non-invasive, sensitive and longitudinal imaging. We have evaluated the feasibility of X-ray fluorescence imaging (XFI) to track immune cells and thus monitor the immune response. For that, we have performed Monte Carlo simulations using a mouse voxel model. Spherical targets, enriched with gold or palladium fluorescence agents, were positioned within the model and imaged using a monochromatic photon beam of 53 or 85 keV. Based on our simulation results, XFI may detect as few as 730 to 2400 T cells labelled with 195 pg gold each when imaging subcutaneous tumors in mice, with a spatial resolution of 1 mm. However, the detection threshold is influenced by the depth of the tumor as surrounding tissue increases scattering and absorption, especially when utilizing palladium imaging agents with low-energy characteristic fluorescence photons. Further evaluation and conduction of in vivo animal experiments will be required to validate and advance these promising results.
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Kilovoltage therapy is well and truly alive and needed in a modern radiotherapy centre. Phys Eng Sci Med 2021; 44:341-345. [PMID: 33899157 DOI: 10.1007/s13246-021-00998-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Editorial. Phys Med 2020; 79:ii-v. [DOI: 10.1016/j.ejmp.2020.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/20/2020] [Indexed: 11/20/2022] Open
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