Deoxyhemoglobin from patients homozygous for sickle-cell anemia (deoxyhb S) aggregates into long straight fibers. These may extend through most of the length of the sickled cell, forming either square or hexagonally packed bundles with lattice constants of 170-180 A. Each fiber is a tube made up of six thin filaments, which are wound around the tubular surface with a helical pitch of about 3000...

The rate of assembly of oxyhemoglobins A and S at pH 7 and 20 degrees C has been followed spectrophotometrically at 582.5 nm, a maximum of the difference spectrum of isolated oxygenated subunits and intact oxyhemoglobin. In 0.1 M potassium phosphate buffer, the resultant time courses following mixing of equivalent concentrations of alpha and beta chains were homogeneous and followed first order...

Red blood cells from patients with sickle cell disease (SCD) exhibit increased electrogenic cation permeability, particularly following deoxygenation and hemoglobin (Hb) polymerisation. This cation permeability, termed Psickle, contributes to cellular dehydration and sickling, and its inhibition remains a major goal for SCD treatment. Nevertheless, its characteristics remain poorly defined, its...

nurse specialist at Swedish Medical Center in Seattle, Wash. lengths in the red and infrared spectra through an optical fiber to illuminate the blood. The red blood cells absorb various amounts of light depending on the amounts of oxygenated and deoxygenated hemoglobin that are present. The light reflected by the blood cells is transmitted through a second optical fiber to the photodetector, wh...

Red blood cells from patients with sickle cell disease (SCD) exhibit increased electrogenic cation permeability, particularly following deoxygenation and hemoglobin (Hb) polymerisation. This cation permeability, termed P(sickle), contributes to cellular dehydration and sickling, and its inhibition remains a major goal for SCD treatment. Nevertheless, its characteristics remain poorly defined, i...

patients, we have studied the viscosimetric and hemodynamic characteristics of four major classes of hemoglobin SS erythrocytes. We have isolated reticulocytes, discocytes, dense discocytes, and irreversibly sickled cells (fractions I-IV) on Percoll-Renografin density gradients. Bulk viscosity was studied in a coneplate viscosimeter and the hemodynamic studies were performed on the isolated, ar...

Arecent flurry of research papers and commentaries in this journal1–4 has highlighted a current major controversy in cardiovascular biochemistry and physiology: how is nitric oxide (NO) transported in the bloodstream. Two views have arisen. First, that S-nitrosated hemoglobin and albumin serve as stable storage forms of intravascular NO, and, in the case of S-nitrosated hemoglobin, as an allost...

BACKGROUND AND OBJECTIVE Transcranial laser stimulation of the brain with near-infrared light is a novel form of non-invasive photobiomodulation or low-level laser therapy (LLLT) that has shown therapeutic potential in a variety of neurological and psychological conditions. Understanding of its neurophysiological effects is essential for mechanistic study and treatment evaluation. This study in...

Arecent flurry of research papers and commentaries in this journal1–4 has highlighted a current major controversy in cardiovascular biochemistry and physiology: how is nitric oxide (NO) transported in the bloodstream. Two views have arisen. First, that S-nitrosated hemoglobin and albumin serve as stable storage forms of intravascular NO, and, in the case of S-nitrosated hemoglobin, as an allost...

Near-infrared spectroscopy (NIRS), which can be used to detect changes in the concentration of oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) in tissue by using illumination at two different wavelengths, is often applied to noninvasive measurements of human brain functions. It is common to use two wavelengths that are on opposite sides of the point where the optical absor...