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Ozone Therapy in Oncology Patients
Published in Paloma Tejero, Hernán Pinto, Aesthetic Treatments for the Oncology Patient, 2020
Ozone can increase 2,3-DPG (2,3 diphosphoglycerate) in erythrocytes, which produces changes in the dissociation curve of hemoglobin (Hb), shifting the balance HbO2/Hb to the right (HbO2 + 2,3-DPG → Hb-2,3-DPG + O2). It has been described that this increase could only occur in those patients with decreased baseline levels (pre-O3) [3]. The production of the Bohr effect could also contribute to this effect on Hb. The final result is that Hb increases the transfer of O2 to tissues [14].
Gas Exchange in the Lungs
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
As the tissue is low, oxygen diffuses down the partial pressure gradient and out of the blood. The blood falls, and oxygen is released from haemoglobin into physical solution. The process continues until adequate oxygen has been released from the blood for aerobic metabolism (each 100 mL of blood loses 5 mL of oxygen, and the falls from 100 to 40 mmHg [13.3 to 5.3 kPa]). The gradient from the blood to the tissues is maintained by the steep part of the oxygen–haemoglobin dissociation curve as blood tends to be maintained while oxygen is lost. The higher tissue , temperature and hydrogen ion concentration encourage oxygen release by haemoglobin via the Bohr effect.
Carbon Monoxide Poisoning, Methemoglobinemia, and Sulfhemoglobinemia
Published in Harold R. Schumacher, William A. Rock, Sanford A. Stass, Handbook of Hematologic Pathology, 2019
Hb binds hydrogen ions efficiently in a low-pH environment and releases hydrogen ions when it encounters high pH (a phenomena called the Bohr effect). The Bohr effect is the change of O2 affinity secondary to pH change within a certain range: the lower the pH, the lower is the affinity for O2. This means that an increased concentration of protons favors low affinity in Hb; deoxy-Hb binds more protons than the oxy-conformer.
Hb Q-Thailand heterozygosity unlinked with the (–α4.2/) α+-thalassemia deletion allele identified by long-read SMRT sequencing: hematological and molecular analyses
Published in Hematology, 2023
Danqing Qin, Jicheng Wang, Cuize Yao, Xiuqin Bao, Jie Liang, Li Du
Hb Q-Thailand is a slow-moving abnormal hemoglobin that is characterized by a substitution of aspartic acid with histidine at the 74th position of the normal α1-globin chain. This hemoglobin shows normal oxygen affinity, a normal Bohr effect and normal cooperativity because the substituted amino acid is nonfunctional [8]. It was first observed in 1958 by Vella et al. in Singapore and first discovered in the Chinese population in 1983 by Zeng et al. [9,10]. Hb Q-Thailand has a high detection rate in southern China and Southeast Asian countries, where it occurs mostly in a heterozygous or compound heterozygous state with α0-thalassemia, causing Hb Q-H disease [3,4,8,11–13]. Although Hb Q-Thailand has been found in various populations, the present study is the first to report a negative result for DNA analysis of the (–α4.2/) deletion.
First study to describe a novel HbA2: c.400A > C mutation and Hb Dongguan heterozygote in two unrelated Chinese families
Published in Hematology, 2022
Cuize Yao, Danqing Qin, Jicheng Wang, Xiuqin Bao, Jie Liang, Li Du
The mutation causing amino acid changes at codon 133 [α133(H16) Ser > Arg] corresponds to that found in Hb Val de Marne [4,8–11], which was reported to present normal haematologic parameters, with 16% abnormal Hb [8]. Additionally, the Hb stability of Hb Val de Marne was normal [8, 9]. However, the oxygen affinity was increased, while the haem-haem interaction was slightly reduced and the chloride ion binding and Bohr effect remained normal. The reason may be that serine (a133(H16)) is the residue at the C-terminus of the α-globin chain, which is in contact with the haem pocket (Phe a98(C5)) and other internal residues (Lys a99(G6), Ser a102(G9) and Ser a138 (H21)), and this replacement of Ser by Arg may help oxygen or water interact with the haem iron. Regarding the molecular characteristics of Hb Val de Marne, Edmond Shiu-Kwan Ma et al. [4] first revealed an AGC > AGA mutation at codon 133 of the α2 gene in a Chinese family. Based on amino acid analysis, replacing serine at 133 of the codon of the α2 gene with arginine requires only a single mutation in the codon, which can be A→C (our report), C→G, or C→A (2004).
CO2 permeability of the rat erythrocyte membrane and its inhibition
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Samer Al-Samir, Maximilian Prill, Claudiu T. Supuran, Gerolf Gros, Volker Endeward
We report here an intraerythrocytic carbonic anhydrase activity of 64,100, which may be compared with the value of 21,000 we obtained for human red cells with the same method under identical conditions4. Thus, rat red cells have a 3 times higher Ai compared to human red cells. While the absolute numbers of these activities cannot be compared with the results obtained by Larimer and Schmidt-Nielsen19 due to highly different methods and conditions, it may be noted that these authors similarly found a 2.5 times higher Ai in rats compared to humans. In general, these authors observed a tendency of Ai to increase with decreasing body weight in mammals. The functional significance of the higher Ai values in smaller animals is not clear. Larimer and Schmidt-Nielsen speculated that the high carbonic anhydrase activity in small animals with their higher specific rate of oxygen consumption may improve oxygen release from red cells by an accelerated production of H+ from CO2, thus accelerating the contribution of the Bohr effect to O2 release19. Their studies have been discussed and updated in a more recent review20.