Differential response of chloride binding sites to elevated temperature: a comparative study in spinach thylakoids and PSII-enriched membranes

In Japan, a new standard of an assessment procedure for crack-like flaws in pressure equipment at elevated temperature is now under development in the High Pressure Institute of Japan (HPI). In this standard development, it is needed to adopt reference stress solutions for crack-like flaws in pressure equipment being subjected to membrane stress and/or bending stress. Such reference stress solutions have been proposed in various references such as ASME FFS-1/API579-1, BS7910, R5, FBR draft guideline, HPIS Z101-2, etc. A comparative study of those reference stress solutions was conducted in order to select appropriate one. As a result, reference stress solutions in HPIS Z101-2 were adopted. The sufficiency of adopted reference stress solutions was introduced in this paper. Also, the reference stress solutions for axially and circumferentially through-wall rectangular flawed cylinders, which were not provided in the HPIS Z101-2 standard but were utilized to derive those solutions adopted in the standard, were introduced in this paper. These solutions should be adopted in a new HPI standard for crack-like flaws in pressure equipment at elevated temperature.

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Use of ionic and zwitterionic (Tris/BisTris and HEPES) buffers in studies on hemoglobin function

Journal of Applied Physiology ◽

10.1152/jappl.1992.72.4.1611 ◽

1992 ◽

Vol 72 (4) ◽

pp. 1611-1615 ◽

Cited By ~ 70

Author(s):

R. E. Weber

Keyword(s):

Binding Sites ◽

Ionic Composition ◽

Oxygen Affinity ◽

Chloride Concentration ◽

Anion Binding ◽

Chloride Binding ◽

Ph Values ◽

Two Temperatures ◽

Ethanesulfonic Acid ◽

Chloride Concentrations

The functional characteristics of hemoglobin (Hb) depend on oxygenation-linked proton and anion binding and thus on solvent buffer groups and ionic composition. This study compares the oxygenation properties of human Hb in ionic [tris(hydroxymethyl)aminomethane (Tris) and BisTris] buffers with those in zwitterionic N-2-hydroxy-ethylpiperazine-N′-2-ethanesulfonic acid (HEPES) buffer under strictly controlled chloride concentrations at different pH values, two temperatures, and in the absence and presence of the erythrocytic cofactor, 2,3-diphosphoglycerate (DPG). In contrast to earlier studies (carried out at the same or different chloride concentrations) it shows only small buffer effects that are manifested at low chloride concentration and high pH. These observations suggest chloride binding to the Tris buffers, which reduces the interaction with specific chloride binding sites in the Hb. The findings indicate that HEPES allows for more accurate assessment of Hb-oxygen affinity and its anion and temperature sensitivities than ionic buffers and advocates standard use of HEPES in studies on Hb function. Precise oxygen affinities of Hb dissolved in both buffers are defined under standard conditions.

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A comparative study on characterization and distribution of cholecystokinin binding sites among the rat, mouse and guinea pig brain

Brain Research ◽

10.1016/0006-8993(86)91517-9 ◽

1986 ◽

Vol 399 (2) ◽

pp. 271-281 ◽

Cited By ~ 46

Author(s):

Ryuichi Sekiguchi ◽

Takashi Moroji

Keyword(s):

Guinea Pig ◽

Comparative Study ◽

Binding Sites ◽

Pig Brain ◽

Guinea Pig Brain

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Distinct localization of atrial natriuretic factor and angiotensin II binding sites in the glomerulus

AJP Renal Physiology ◽

10.1152/ajprenal.1986.251.4.f594 ◽

1986 ◽

Vol 251 (4) ◽

pp. F594-F602 ◽

Cited By ~ 2

Author(s):

C. Bianchi ◽

J. Gutkowska ◽

G. Thibault ◽

R. Garcia ◽

J. Genest ◽

...

Keyword(s):

Angiotensin Ii ◽

Comparative Study ◽

Binding Sites ◽

Atrial Natriuretic Factor ◽

Mesangial Cells ◽

Ang Ii ◽

Half Maximum ◽

Natriuretic Factor ◽

Glomerular Size ◽

Atrial Natriuretic

A comparative study of the localization of 125I-labeled atrial natriuretic factor (ANF) and 125I-labeled angiotensin II (ANG II) binding sites in the glomerulus of the rat, after an intravascular injection, has been done by ultrastructural radioautography. 125I-ANF binding sites are localized predominantly on the podocytes of the visceral epithelium (63%) followed by the endothelium of capillaries (14%), the parietal epithelium (13%), and finally mesangial cells (10%). In a comparative study, it was confirmed that 125I-ANG II uptake is localized predominantly on mesangial cells (60%) followed by epithelial visceral cells (23%) and the endothelium of capillaries (16%). Using isolated rat glomeruli, it was confirmed that ANG II decreases glomerular size (maximum effect of 15%) with an apparent half maximum effective concentration (EC50) between 10(-9) and 10(-8) M. Although ANF alone has no apparent effect on glomerular size, it inhibits the contractile effect of ANG II with a half maximum inhibitory concentration (IC50) between 10(-11) and 10(-10) M. These results suggest that an intraglomerular mechanism other than glomerular arteriolar resistance may be involved in the modulation of glomerular filtration rate by ANF. The presence of 125I-ANF uptake mainly in foot processes of visceral epithelial cells of glomeruli in vivo and the inhibition of ANG II decrease in glomerular size by ANF in vitro raise the possibility that ANF may regulate the ultrafiltration coefficient by two mechanisms: modulation of glomerular permeability, and surface area.

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