scholarly journals Oxygen dissociation curves of the blood of larval and adult lampreys (Lampetra fluviatilis)

1976 ◽  
Vol 65 (2) ◽  
pp. 449-458
Author(s):  
D. J. Bird ◽  
P. L. Lutz ◽  
I. C. Potter

1. An electrolytic method was used to plot the oxygen dissociation curves of whole blood from both the larva and adult of the lamprey Lampetra fluviatilis at a temperature of 10 degrees C and over a pH range of 6-5-8-1. 2. Larval blood has a far higher affinity for oxygen than that of adults, the respective calculated P50's at a pH of 7–75 being 1-9 and 10-7 mmHg. 3. The high affinity of larval blood is of use to a relatively sedentary animal living in burrows, and the increased oxygen delivery pressure brought about by the shift of the curve to the right in the adult is of advantage to an animal exhibiting greater activity. 4. The n value obtained from the Hill plots increased with increasing saturation and were lower in larvae than adults at the same level of blood saturation. 5. The Bohr effect in larvae at 10 degrees C over the pH range 6-5-8-1 was --0-25, a value which did not differ significantly from the −0-22 found in adults.

1982 ◽  
Vol 97 (1) ◽  
pp. 253-261
Author(s):  
D. J. Macey ◽  
I. C. Potter

1. Oxygen dissociation curves of the whole blood of larvae and adults of the Southern Hemisphere lamprey Geotria australis have been determined between pH 6.8 and 8.2 at 5, 15 and 25 degrees C. 2. The P50's at temperatures of 5, 15 and 25 degrees C and a pH of 7.75 were respectively 0.57, 0.92 and 1.19 mmHg in larvae and 6.9, 10.3 and 19.0 mmHg in adults. 3. The relatively very high affinity of larval blood for oxygen may reflect an adaptation to low environmental oxygen tensions. 4. The Bohr shift was not significantly affected by either temperature or life-cycle stage. 5. The slope (n) in Hill plots increased with temperature and oxygen saturation, and was greater in adults than in larvae.


1997 ◽  
Vol 82 (1) ◽  
pp. 86-92 ◽  
Author(s):  
Kenneth A. Schenkman ◽  
David R. Marble ◽  
David H. Burns ◽  
Eric O. Feigl

Schenkman, Kenneth A., David R. Marble, David H. Burns, and Eric O. Feigl. Myoglobin oxygen dissociation by multiwavelength spectroscopy. J. Appl. Physiol. 82(1): 86–92, 1997.—Multiwavelength optical spectroscopy was used to determine the oxygen-binding characteristics for equine myoglobin. Oxygen-binding relationships as a function of oxygen tension were determined for temperatures of 10, 25, 35, 37, and 40°C, at pH 7.0. In addition, dissociation curves were determined at 37°C for pH 6.5, 7.0, and 7.5. Equilibration was achieved with a myoglobin solution, at the desired temperature and pH, and 16 oxygen-nitrogen gas mixtures of known oxygen fraction. Correction for the inevitable presence of metmyoglobin was made by using a three-component least squares analysis and by correcting the end point oxymyoglobin spectra for the presence of metmyoglobin. The[Formula: see text] at which myoglobin is half-saturated with O2(P50) was determined to be 2.39 Torr at pH 7.0 and 37°C. The myoglobin dissociation curve was well fit by the Hill equation [saturation =[Formula: see text]/([Formula: see text]+ P50)].


PEDIATRICS ◽  
1977 ◽  
Vol 59 (6) ◽  
pp. 1027-1031
Author(s):  
Barry D. Chandler ◽  
William J. Cashore ◽  
Pierre J. P. Monin ◽  
William Oh

Phototherapy has been shown to cause hemolysis of fetal red cells and a shift to the right in the neonatal oxygen dissociation curve (ΔP50) in vitro. To determine if these parameters act similarly in vivo, we have studied 16 icteric infants before and after phototherapy and compared them with eight control infants studied at birth and at 3 days of age, measuring the change in P50, 2,3-diphosphoglycerate (2,3-DPG), serum bilirubin, the percent of bilirubin/albumin saturation, and the hemoglobin concentration in the two groups. Following phototherapy, in the icteric infants there was a shift to the right in the O2 dissociation curve of + 1.7 mm Hg, a rise in 2,3-DPG of 2.26 µmol/gm Hb, a fall in serum bilirubin of 4.3 mg/100 ml, a decrease in percent bilirubin/albumin saturation of 12.4%, and a drop in hemoglobin of 1.1 gm/100 ml. The control group showed a ΔP50 of + 2.0 mm Hg, a rise in 2,3-DPG of 3.67 µmol/gm Hb, an increase in serum bilirubin of 3.2 mg/100 ml, an increase in percent bilirubin/albumin saturation of 9.3%, and a fall in hemoglobin of 0.3 gm/100 ml. Significant differences between the groups were seen only in the changes in bilirubin concentration and percent bilirubin/albunmin saturation. The magnitude of changes in P50, 2,3-DPG, and hemoglobin concentration was similar in the phototherapy and control groups and was related to the expected changes with reference to postnatal age. These results suggest that phototherapy in vivo neither affects fetal erythrocytic affinity for oxygen nor causes hemolysis.


1976 ◽  
Vol 230 (2) ◽  
pp. 471-475 ◽  
Author(s):  
Y Okada ◽  
I Tyuma ◽  
Y Ueda ◽  
T Sugimoto

Oxygen dissociation curves of partially CO-saturated human whole blood drawn freshly or preserved more than 3 wk were studied. With increasing CO-hemoglobin concentrations, oxygen affinity of the blood increased and the Hill coefficient, n, fell and gradually approached unity. The changes induced by CO-hemoglobin showed practically no difference in the presence or absence of 2,3-diphosphoglycerate. The Bohr coefficient, deltalog P50/deltapH, was determined as a function of oxygen saturation for various concentrations of CO-hemoglobin. The coefficient remained essentially unchanged in the presence of CO-hemoglobin. In the presence of less than 50% CO-hemoglobin, a good agreement was observed between the observed oxygen dissociation curves and the curves calculated according to Roughton and Darling (Am. J. Physiol. 141: 17-31, 1944). Based on these results, physiological implications of carboxyhemoglobinemia are discussed quantitatively in comparison with methemoglobinemia.


Blood ◽  
1969 ◽  
Vol 34 (5) ◽  
pp. 682-690 ◽  
Author(s):  
M. J. CAWEIN ◽  
R. P. O’NEILL ◽  
L. A. DANZER ◽  
E. J. LAPPAT ◽  
THOMAS ROACH

Abstract 1. Data on pO2, T50, n values and per cent of sickle cells were obtained in patients with hemoglobins SS, SD, SF (S-thalassemia) and SC. In general the per cent of sickle cells was proportional to the per cent of hemoglobin S. The number of sickle cells was, however, influenced by the other type of hemoglobin present and by the pO2. Values for T50 were greater than normal, and values for n were less than normal. 2. The effect of therapy with O2, CO2, NaHCO3 and MgSO4 on the per cent of sickle cells in arterial and venous blood was determined. Only inhalation of O2 reduced the per cent of sickle cells. 3. The rate of sickle cell formation and its reversal were determined under conditions of deoxygenation and oxygenation. These were found to be a function of the type of hemoglobin combinations present. 4. The oxygen dissociation curves were found to be shifted to the right of the normal curve indicating a decreased affinity for oxygen. In two patients the Bohr effect was determined and found to be normal.


1980 ◽  
Vol 93 (4) ◽  
pp. 424-429 ◽  
Author(s):  
J. L. Alvarez-Sala ◽  
M. A. Urbán ◽  
J. J. Sicilia ◽  
A. J. Diaz Fdez ◽  
F. Fdez Mendieta ◽  
...  

Abstract. In 21 hyperthyroid female patients studied on 29 occasions, high levels of red-cell 2,3-diphosphoglycerate (2,3-DPG) have been found (5.75 ± 0.7 mm) which, compared to a euthyroid control group (4.88 ± 0.4 mm), could not be accounted for by differences in haematocrit, haemoglobin or phosphataemia. A significant correlation was found (P < 0.05) between serum thyroid hormones and the 2,3-DPG concentration in the hyperthyroid patients. Eight of these patients were reexamined after treatment and normalization of thyroid function, showed a regression to normal 2,3-DPG values (4.81 ± 0.6 mm) which could not be attributed to variations in haematocrit, haemoglobin or phosphataemia either. We therefore deduce that the shift to the right in the haemoglobin oxygen dissociation curve observed in patients of this type may be due to an increase in the red-cell 2,3-DPG content.


PMLA ◽  
1984 ◽  
Vol 99 (3) ◽  
pp. 371-397 ◽  
Author(s):  
Geoffrey H. Hartman

For those who approach literary studies with literary sensitivity, an immediate problem arises. They cannot overlook style, their own or that of others. Through their concern with literature they have become aware that understanding is a mediated activity and that style is an index of how the writer deals with the consciousness of mediation. Style is not cognitive only; it is also recognitive, a signal betraying the writer's relation, or sometimes the relation of a type of discourse, to a historical and social world. To say that of course words are a form of life is not enough: words at this level of style intend a statement about life itself in relation to words, and in particular to literature as a value-laden act. Thus, even without fully understanding it, one is alerted by a similarity in the opening of these two essays: The Right Reverend Father in God, Lancelot Bishop of Winchester, died on September 26th, 1626. During his lifetime he enjoyed a distinguished reputation for the excellence of his sermons, for the conduct of his diocese, for his ability in controversy displayed against Cardinal Bellarmine, and for the decorum and devotion of his private life. (Eliot, Lancelot 13) One afternoon, Walter Benjamin was sitting inside the Café des Deux Magots in Saint Germain des Prés when he was struck with compelling force by the idea of drawing a diagram of his life, and knew at the same moment exactly how it was to be done. He drew the diagram, and with utterly typical ill-luck lost it again a year or two later. The diagram, not surprisingly, was a labyrinth. (Eagleton, Pref.)


The spectroscopic determination of the oxygen dissociation curves of haemoglobin has an advantage over the tonometer and gas analysis method, in that much smaller quantities of haemoglobin can be made use of. The spectroscopic method was used to determine the relationship between the foetal and maternal haemoglobins in the sheep during a study of foetal respiration made by Barcroft (1935). The conditions for the comparison of the haemoglobins were a dilute solution of the haemoglobin at p H 9·2 (borate buffer) and at 20° C. These conditions were chosen because of the very accurate determinations of the dissociation curves of dilute haemoglobin of the sheep by Forbes and Roughton (1931) and because these authors recommend p H 9·2 at room temperature as most suitable for a study of the oxygen equilibrium of haemoglobin, all the haemoglobin being in the form of the alkali salt. McCarthy (1933) and Hall (1934) had found previously that the haemoglobins of the foetal and maternal goat were different, the foetal haemoglobin (in the blood and as purified haemoglobin) having a higher affinity for oxygen. The same relationship was found to exist in the sheep haemoglobins in dilute solution at 20° C and p H 9·2. When samples of human foetal and maternal blood (sent by Professor Fleming from the Obstetrical Department of the Royal Free Hospital) were compared in dilute solution it was found that the foetal haemoglobin had a lower affinity for oxygen than the maternal. This was also found by Haurowitz (1935) for dilute solutions of the haemoglobins of mother and new born infant. Haurowitz, however, pointed out that in the corpuscles the affinity for oxygen is less in the infant’s haemoglobin than in that of the mother, but the method used by him did not allow of measurements on suspensions of corpuscles. In the present work the dissociation curves of dilute suspensions of corpuscles have been compared with similar solutions of the haemoglobin. It was found that the relationship of the dissociation curves for human foetal and maternal corpuscles is the same as that found by Barcroft in the goat and in the sheep. It has now been found that by a dilution of human adult haemoglobin the dissociation curve is altered by 200% to a position of higher affinity for oxygen, without any marked change in shape. The haemoglobin of the human foetus, on the other hand, is much less affected by dilution, thus explaining the anomaly of the reversed relationship when solutions of the haemoglobins are used instead of suspensions of corpuscles. It was shown by the work of Bock, Field, and Adair (1924), and by Adair (1925), that a solution of haemoglobin free from stromata and of a similar concentration to blood gives a dissociation curve like whole blood. This makes it clear that in the comparison of dilute haemoglobin solutions with suspensions of corpuscles we are concerned, not simply with a change in the haemoglobin due to haemolysis, but a change due to a dilution of the contents of the corpuscle.


Author(s):  
Andi Sartina Ningsih ◽  
Baharuddi n ◽  
Daud Malamassam

The use of candlenut (Aleurites Mollucana., L. Wild) as a non-timber forest product is expected to be a excellent product in the KPHL of Selayar in line with the designation of the area as a Protected Forest Management Unit (KPHL). Candlenut is a non-timber forest product (NTFP) which has great economic potential, but in the management of the candlenut business in the KPHL Selayar has not been able to be optimally developed as the scale of the use of candlenut remain low and the business model conducted appears to be traditional. The study aimed to analyze and identify internal and external factors in formulating the right strategic priorities in the development of the candlenut business at KPHL Selayar. The method employed was a combination of SWOT and AHP by describing internal and external factors, then tabulating it so that it would formulate a priority of strategic choices. The results showed that among the four SWOT groups namely Strengths (S), Weaknesses (W), Opportunities (O) and Threats (T) which became the priority of the SWOT group which had a great influence on the development of the candlenut business, the Strength (S) group with a value of 10.55. Based on the formulated results of the candlenut business development strategy, it was concluded that the priority strategy to be implemented was the S-O 3 strategy, namely increasing the candlenut business collaboration to expand the marketing network with a priority value of 0.107.


Sign in / Sign up

Export Citation Format

Share Document