scholarly journals JAK2 unmutated erythrocytosis: current diagnostic approach and therapeutic views

Leukemia ◽  
2021 ◽  
Author(s):  
Naseema Gangat ◽  
Natasha Szuber ◽  
Animesh Pardanani ◽  
Ayalew Tefferi
Keyword(s):  
Symptom Control ◽  
Oxygen Affinity ◽  
Diagnostic Approach ◽  
Phenotypic Characterization ◽  
Risk Optimization ◽  
Thrombosis Risk ◽  
Serum Erythropoietin Level ◽  
Hard Evidence ◽  
High Oxygen Affinity ◽  
Intervention Trials

AbstractJAK2 unmutated or non-polycythemia vera (PV) erythrocytosis encompasses both hereditary and acquired conditions. A systematic diagnostic approach begins with documentation of historical hematocrit (Hct)/hemoglobin (Hgb) measurements and classification of the process as life-long/unknown duration or acquired. Further investigation in both categories is facilitated by determination of serum erythropoietin level (EPO). Workup for hereditary/congenital erythrocytosis requires documentation of family history and laboratory screening for high-oxygen affinity hemoglobin variants, 2, 3 biphosphoglycerate deficiency, and germline mutations that are known to alter cellular oxygen sensing (e.g., PHD2, HIF2A, VHL) or EPO signaling (e.g., EPOR mutations); the latter is uniquely associated with subnormal EPO. Acquired erythrocytosis is often elicited by central or peripheral hypoxia resulting from cardiopulmonary disease/high-altitude dwelling or renal artery stenosis, respectively; EPO in the former instance is often normal (compensated by negative feed-back). Other conditions associated with acquired erythrocytosis include EPO-producing tumors and the use of drugs that promote erythropoiesis (e.g., testosterone, erythropoiesis stimulating agents). “Idiopathic erythrocytosis” loosely refers to an otherwise not explained situation. Historically, management of non-PV erythrocytosis has been conflicted by unfounded concerns regarding thrombosis risk, stemming from limited phenotypic characterization, save for Chuvash polycythemia, well-known for its thrombotic tendency. In general, cytoreductive therapy should be avoided and phlebotomy is seldom warranted where frequency is determined by symptom control rather than Hct threshold. Although not supported by hard evidence, cardiovascular risk optimization and low-dose aspirin use are often advised. Application of modern genetic tests and development of controlled therapeutic intervention trials are needed to advance current clinical practice.

Diagnostic approach to hemoglobins with high oxygen affinity: experience from France and Belgium and review of the literature

2017 ◽  
Vol 75 (1) ◽  
pp. 39-51 ◽  
Author(s):  
Corentin Orvain ◽  
Philippe Joly ◽  
Serge Pissard ◽  
Stéphanie Badiou ◽  
Catherine Badens ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
Diagnostic Approach ◽  
Review Of The Literature ◽  
High Oxygen Affinity

Hemoglobin fort gordon or α2β2145 Tyr → Asp, a new high-oxygen-affinity hemoglobin variant

1975 ◽  
Vol 400 (2) ◽  
pp. 343-347 ◽  
Author(s):  
H.B. Kleckner ◽  
J.B. Wilson ◽  
J.G. Lindeman ◽  
P.D. Stevens ◽  
G. Niazi ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
Hemoglobin Variant ◽  
High Oxygen Affinity

scholarly journals Pyrometallurgical Lithium-Ion-Battery Recycling: Approach to Limiting Lithium Slagging with the InduRed Reactor Concept

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 84
Author(s):  
Stefan Windisch-Kern ◽  
Alexandra Holzer ◽  
Christoph Ponak ◽  
Harald Raupenstrauch
Keyword(s):  
Removal Rate ◽  
Oxygen Affinity ◽  
Lithium Ion ◽  
Transfer Coefficients ◽  
Scanning Calorimetry ◽  
Recycling Industry ◽  
Reducing Conditions ◽  
Novel Approach ◽  
Input Material ◽  
High Oxygen Affinity

The complexity of the waste stream of spent lithium-ion batteries poses numerous challenges on the recycling industry. Pyrometallurgical recycling processes have a lot of benefits but are not able to recover lithium from the black matter since lithium is slagged due to its high oxygen affinity. The presented InduRed reactor concept might be a promising novel approach, since it does not have this disadvantage and is very flexible concerning the chemical composition of the input material. To prove its basic suitability for black matter processing, heating microscope experiments, thermogravimetric analysis and differential scanning calorimetry have been conducted to characterize the behavior of nickel rich cathode materials (LiNi0.8Co0.15Al0.05O2 and LiNi0.33Mn0.33Co0.33O2) as well as black matter from a pretreatment process under reducing conditions. Another experimental series in a lab scale InduRed reactor was further used to investigate achievable transfer coefficients for the metals of interest. The promising results show technically feasible reaction temperatures of 800 ∘C to 1000 ∘C and high recovery potentials for nickel, cobalt and manganese. Furthermore, the slagging of lithium was largely prevented and a lithium removal rate of up to 90% of its initial mass was achieved.

scholarly journals Genetic Background of Congenital Erythrocytosis

Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1151
Author(s):  
Mary Frances McMullin
Keyword(s):  
Receptor Gene ◽  
Cell Mass ◽  
Oxygen Affinity ◽  
Young Age ◽  
Erythropoietin Receptor ◽  
Congenital Defects ◽  
History Of ◽  
Genetic Mechanisms ◽  
High Oxygen Affinity ◽  
Hemoglobin Variants

True erythrocytosis is present when the red cell mass is greater than 125% of predicted sex and body mass, which is reflected by elevated hemoglobin and hematocrit. Erythrocytosis can be primary or secondary and congenital or acquired. Congenital defects are often found in those diagnosed at a young age and with a family history of erythrocytosis. Primary congenital defects mainly include mutations in the Erythropoietin receptor gene but SH2B3 has also been implicated. Secondary congenital erythrocytosis can arise through a variety of genetic mechanisms, including mutations in the genes in the oxygen sensing pathway, with high oxygen affinity hemoglobin variants and mutations in other genes such as BPMG, where ultimately the production of erythropoietin is increased, resulting in erythrocytosis. Recently, mutations in PIEZ01 have been associated with erythrocytosis. In many cases, a genetic variant cannot be identified, leaving a group of patients with the label idiopathic erythrocytosis who should be the subject of future investigations. The clinical course in congenital erythrocytosis is hard to evaluate as these are rare cases. However, some of these patients may well present at a young age and with sometimes catastrophic thromboembolic events. There is little evidence to guide the management of congenital erythrocytosis but the use of venesection and low dose aspirin should be considered.

Germline mosaicism for an alanine to valine substitution at residue ? 140 in hemoglobin Puttelange, a new variant with high oxygen affinity

1995 ◽  
Vol 96 (6) ◽  
pp. 711-716 ◽  
Author(s):  
H. Wajcman ◽  
E. Girodon ◽  
D. Prom� ◽  
M.L. North ◽  
F. Plassa ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
Germline Mosaicism ◽  
New Variant ◽  
High Oxygen Affinity

Unusual finding of high oxygen affinity haemoglobinopathy treated with phlebotomy: a rare but predictable union

2021 ◽  
pp. 103290
Author(s):  
Epifania Rita Testa ◽  
Adriana Masotti ◽  
Patrizia Valeri ◽  
Luciana Geremia ◽  
Valeria Brunetta ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
High Oxygen Affinity ◽  
Unusual Finding

scholarly journals Haemoglobin Olympia {β Codon 20 (B2) G→A, Val→Met}: A Silent Haemoglobin Variant

2021 ◽  
Author(s):  
Abhay A Bhave ◽  
Lakshmi Iyer ◽  
Nawal Kazi ◽  
Manju Gorivale ◽  
Anita Nadkarni
Keyword(s):  
High Performance ◽  
Extended Family ◽  
Globin Gene ◽  
Oxygen Affinity ◽  
High Oxygen ◽  
Cerebral Vessel ◽  
Haemoglobin Variant ◽  
First Case ◽  
History Of ◽  
High Oxygen Affinity

High oxygen affinity haemoglobin variants are rare and often underdiagnosed in persistent erythrocytosis with no apparent aetiology. Here the author present a 29-year-old Indian male patient with a long-standing history of erythrocytosis which was incidentally detected. The proband had a prothrombotic family history of cerebral vessel stroke in his paternal grandfather at a young age and unexplained erythrocytosis in his father and brother. A review of his haemograms showed persistent high haemoglobin values. Routine tests did not reveal any specific aetiology and haemoglobin electrophoresis by High-Performance Liquid Chromatography (HPLC) showed absence of any abnormal peak or unstable haemoglobin. DNA sequencing of the β globin gene revealed heterozygosity for codon 20 {GTG→ATG, Valine (Val)→ Methionine (Met)} mutation confirming the presence of an electrophoretically silent Hb variant - Haemoglobin Olympia in him and his extended family members. This case study emphasises importance of this rare entity of high oxygen affinity haemoglobin variant as a differential diagnosis while screening for erythrocytosis. This is the first case report of Haemoglobin Olympia from India reported in the literature.

scholarly journals Novel Reiterated Fnr-Type Proteins Control the Production of the Symbiotic Terminal Oxidase cbb3 in Rhizobium etli CFN42

2007 ◽  
Vol 20 (10) ◽  
pp. 1241-1249 ◽  
Author(s):  
Manuel J. Granados-Baeza ◽  
Nicolás Gómez-Hernández ◽  
Yolanda Mora ◽  
María J. Delgado ◽  
David Romero ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Oxygen Affinity ◽  
Structural Similarity ◽  
Transcriptional Regulators ◽  
Terminal Oxidase ◽  
Nitrogen Fixing ◽  
Rhizobium Etli ◽  
High Oxygen Affinity ◽  
Key Genes

Symbiotic nitrogen-fixing bacteria express a terminal oxidase with a high oxygen affinity, the cbb3-type oxidase encoded by the fixNOQP operon. Previously, we have shown that, in Rhizobium etli CFN42, the repeated fixNOQP operons (fixNOQPd and fixNOQPf) have a differential role in nitrogen fixation. Only the fixNOQPd operon is required for the establishment of an effective symbiosis; microaerobic induction of this operon is under the control of at least three transcriptional regulators, FixKf, FnrNd, and FnrNchr, belonging to the Crp/Fnr family. In this work, we describe two novel Crp/Fnr-type transcriptional regulators (StoRd and StoRf, symbiotic terminal oxidase regulators) that play differential roles in the control of key genes for nitrogen fixation. Mutations either in stoRd or stoRf enhance the microaerobic expression of both fixNOQP reiterations, increasing also the synthesis of the cbb3-type oxidase in nodules. Despite their structural similarity, a differential role of these genes was also revealed, since a mutation in stoRd but not in stoRf enhanced both the expression of fixKf and the nitrogen-fixing capacity of R. etli CFN42.

scholarly journals A Newly Characterized Hemoglobin Variant with a High Oxygen Affinity, Hb Fuchu-II, Presenting with Acute Myocardial Infarction

2016 ◽  
Vol 55 (3) ◽  
pp. 285-287
Author(s):  
Raku Son ◽  
Takakazu Higuchi ◽  
Atsushi Mizuno ◽  
Ryosuke Koyamada ◽  
Sadamu Okada ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Oxygen Affinity ◽  
High Oxygen ◽  
Hemoglobin Variant ◽  
High Oxygen Affinity
Sign in / Sign up

Export Citation Format

Share Document