Wyman's equation of 1966 describes the facilitation of flux of a reversibly bound substrate such as oxygen, consequent on the translational diffusion of the binding protein (the carrier). While Wyman's equation, or some modification of it such as that by Murray 2, may provide a realistic description of the flux of oxygen through a dilute solution of haemoglobin (see also Wittenburg), it is unlikely to be the complete explanation, nor even the basis, for oxygen transport through the intact red cell. The mature erythrocyte contains approximately 350 g/l haemoglobin, and while this suggests that only 35% of the available water volume is actually occupied by the protein, the remaining 65% is unavailable for protein translational diffusion due to the mutual exclusion of the haemoglobin molecules. For this reason we have examined other possible mechanisms whereby haemoglobin may facilitate the translational diffusion of oxygen within the erythrocyte. Possible alternatives include rotational diffusion by the haemoglobins, intracellular shuffling of haemoglobins due to shape changes by the erythrocyte, and haemoglobin rotations and oxygen exchange consequent on the charge change which accompanies substration and desubstration of the haemoglobin molecule. Finally the dipole interactions are shown to generate significant intermolecular attractions between adjacent haemoglobins.
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http://dx.doi.org/10.1007/978-0-387-71764-7_12 | DOI Listing |
Biophys Rev
October 2023
Laboratory of DNA-Protein Interactions, Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, 119991 Russia.
J Neurol Phys Ther
October 2023
Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, Illinois (C.C,. J.E.S., R.A., J.D., S.B., S.G., Z.J., J.W., J.Y.); and Northwestern University Interdepartmental Neuroscience, Northwestern University, and Department of Biomedical Engineering, Northwestern University, Chicago, Illinois (J.Y.).
Background/purpose: The Upper Extremity Fugl-Meyer Assessment (UEFMA, maximum 66) is widely used in clinics and research studies to examine poststroke upper extremity (UE) impairment. This study aimed to develop and provide pilot data to support the validity of a remote version of the UEFMA to examine UE impairment after stroke through telerehabilitation.
Methods: Team members developed a remote version of the UEFMA for telerehabilitation (tUEFMA, maximum 44) using subscales II to IV and VII of the UEFMA.
Prev Sci
November 2022
Department of Psychiatry, University of Rochester School of Medicine, Rochester, NY, USA.
Many preventive trials randomize individuals to intervention condition which is then delivered in a group setting. Other trials randomize higher levels, say organizations, and then use learning collaboratives comprised of multiple organizations to support improved implementation or sustainment. Other trials randomize or expand existing social networks and use key opinion leaders to deliver interventions through these networks.
View Article and Find Full Text PDFPrev Med Rep
December 2021
Center for Chronic Disease Outcomes Research, VA Health Services Research and Development Center of Innovation, Minneapolis VA Health Care System, Minneapolis, Minnesota, USA.
Neighborhood-level social determinants are increasingly recognized as factors shaping mental health in adults. Data-driven informatics methods and geographic information systems (GIS) offer innovative approaches for quantifying neighborhood attributes and studying their influence on mental health. Guided by a modification of Andersen's Behavioral Model of Health Service Use framework, this cross-sectional study examined associations of neighborhood resource groups with psychological distress and depressive symptoms in 1,528 U.
View Article and Find Full Text PDFBackground: No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.
Method: This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up.
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