Background: The ability to deform is important for circulating RBCs in vivo, and earlier studies showed that this property can objectively be measured in vitro by the LORCA. In this study it was investigated whether photodynamic treatment of human RBCs (meant to inactivate contaminating pathogens) affects deformability.
Study Design And Methods: WBC-reduced RBC suspensions (30% Hct) were treated with 1,9-dimethylmethylene blue (DMMB) and red light. Changes in deformability were analyzed by LORCA measurements, in which elongation of the cells is measured at increasing shear stress. The effect of DMMB concentration and light dose was determined as well as the interfering effect of two scavengers of reactive oxygen species, that is, dipyridamole and Trolox.
Results: Photodynamic treatment with DMMB resulted in clear changes in RBC deformability. Deformability changes occurred before onset of hemolysis. Under relatively mild treatment conditions, especially deformability at low shear stress was decreased, whereas deformability changes at high shear stress only occurred under harsher treatment conditions. Inclusion of dipyridamole and/or Trolox primarily prevented deformability changes at high shear stress.
Conclusion: LORCA measurements can effectively be used to detect changes in deformability that are induced by photodynamic treatment of human RBCs. A change in deformability represents an early marker of RBC damage under these conditions.
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http://dx.doi.org/10.1046/j.1537-2995.2003.00566.x | DOI Listing |
Sci Adv
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College of Chemistry, Fuzhou University, Fuzhou 350116, China.
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Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
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School of Biotechnology, Centurion University of Technology and Management, Jatni, Bhubaneswar, Odisha, 752050, India.
Gliomas are aggressive intracranial tumors of the central nervous system with a poor prognosis, high risk of recurrence, and low survival rates. Radiation, surgery, and chemotherapy are traditional cancer therapies. It is very challenging to accurately image and differentiate the malignancy grade of gliomas due to their heterogeneous and infiltrating nature and the obstruction of the blood-brain barrier.
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Department of Chemistry, The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Division of Life Science, State Key Laboratory of Molecular Neuroscience, and Department of Chemical & Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.
The two contradictory entities in nature often follow the principle of unity of opposites, leading to optimal overall performance. Particularly, aggregation-induced emission luminogens (AIEgens) with donor-acceptor (D-A) structures exhibit tunable optical properties and versatile functionalities, offering significant potential to revolutionize cancer treatment. However, trapped by low molar absorptivity (ε) owing to the distorted configurations, the ceilings of their photon-harvesting capability and the corresponding phototheranostic performance still fall short.
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