Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Maximal oxygen uptake (VO2 max), lung volumes, and ventilatory responses to carbon dioxide and hypoxia have been measured in identical twin athletes, who were trained to a similar high degree. 2. The results confirm previous findings for VO2 max. and lung volumes in identical twins, and are in keeping with the suggestion that genetic factors play a major part in determining the ventilatory response to carbon dioxide and hypoxia.
Clin Sci Mol Med 1975 Mar
PMID:Maximal oxygen uptake, lung volume and ventilatory response to carbon dioxide and hypoxia in a pair of identical twin athletes. 116 23

1. Leg blood flow, uptake of oxygen and glucose and release of lactate by the leg and changes in intramuscular concentrations of metabolites were studied at rest and during exercise of increasing work loads in thirteen patients with occlusive disease of the iliac or superficial femoral arteries. 2. Leg blood flow (dye-dilution technique) and oxygen uptake during exercise were low and levelled with increasing work load. Considerable increases were noted in muscle lactate concentration and in the net release of lactate from the exercising leg. Muscle content (needle-biopsy technique) of ATP and creatine phosphate decreased during exercise, with an almost complete depletion of creatine phosphate in three patients. The decrease in muscle glycogen during work did not differ significantly from that of control subjects. 3. Repeated exercise after reconstructive surgery showed a considerable improvement in physical working capacity. Leg blood flow and oxygen uptake during exercise were significantly higher than before surgery and increased linearly in relation to work intensity. The decrease in creatine phosphate and lactate concentration of the thigh muscle during exercise was less pronounced and the release of lactate was lower than before vascular reconstruction. 4. It is suggested that the onset of the severe muscle symptoms during exercise in patients with occlusive arterial disease of the leg may be related to a low concentration of ATP and creatine phosphate in the affected muscles.
Clin Sci Mol Med 1975 Sep
PMID:Leg blood flow and muscle metabolism in occlusive arterial disease of the leg before and after reconstructive surgery. 117 42

The structure of octylcarbamoyl-alpha-chymotrypsin to a resolution of 3.0 A is described. The n-octyl side chain of the active site directed irreversible inactivator octyl isocyanate is bound exclusively in the hydrophobic substrate binding pocket. The n-octyl isocyanate forms a planar urethane bond with the Ser-195 Ogamma and extends approximately 1 A deeper into the hydrophobic pocket than the indolyl group of indoleacryloyl-alpha-chymotrypsin (Henderson, R. (1970), J. Mol. Biol. 54, 341). All the structural changes are essentially identical with those observed in indoleacryloyl-alpha-chymotrypsin including the observation of a hydrogen bonded water molecule between the carbonyl oxygen of the octylcarbamoyl group and the imidazole group of His-57. The observed mode of n-octyl alkyl binding to chymotrypsin is consistent with the hypothesis proposed earlier (Brown, W. E. and Wold, F. (1973), Biochemistry 12, 828).
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PMID:Alkyl isocyanates as active site-specific reagents for serine proteases. Location of alkyl binding site in chymotrypsin by X-ray diffraction. 119 30

1. Six male subjects performed simulataneous static (hand-grip) and rhythmic (bicycle ergometer) exercises while their respiratory responses were measured. 2. Oxygen consumption increased with the intensity of rhythmic work load, with a modest additional oxygen consumption accompanying the addition of static effort during the rhythmic exercise. 3. Minute ventilation (VE) increased directly with rhythmic exercise, but increased disproportionately to the metabolic need when static effort was added. The mean increment of VE elicited by the static exercise influence was nearly constant at 20 l/min, regardless of the rhythmic load present. 4. Possible reflex mechanisms which result in disruption of the normally well-matched ventilation and metabolic oxygen demands whenever static effort is present are discussed.
Clin Sci Mol Med 1975 Nov
PMID:Respiratory responses to simultaneous static and rhythmic exercises in humans. 119 99

A hypothesis about the evolution of the haem-haem interaction in haemoglobins has been formulated on the basis of available functional and structural data. It emerges that this cooperative muchanism is not necessarily due solely to the higher levels of protomer aggregation, because it occurs only in haemoglobins having the distal histidine. It is thus proposed that this amino acid residue might have had a significant role for the development of low-oxygen-affinity haemoglobins in vertebrates.
J Mol Evol 1975 Nov 04
PMID:Evolution of the haem-haem interaction in vertebrate haemoglobins - a hypothesis. 120 26

The present status of our knowledge of different levels of hemoglobin molecule structural organization and of the conformation changes accompanying a hemoglobin action is reviewed. The main functional properties of hemoglobin such as cooperative effects in oxygen binding. CO2 transport, protons and organic phosphates effects on oxygen affinity are described on molecular ground. The description is based on the data obtained by different physical and chemical methods especially by X-ray analysis. The application of some mathematical models of cooperative effects in enzymes to hemoglobin is discussed.
Mol Biol (Mosk)
PMID:[Structure and functions of hemoglobin]. 121 69

Using an Cphi-4A spectrophotometer (USSR), denaturation of DNA containing approximately 2% residual protein has been studied in the presence of catecholamines and their precursors: epinephrine, beta-3,4-dioxyphenylalanine, norepinephrine, 3,4-dimethoxyphenylethylamine, tyrosine, and phenylalanine. All these substances, excluding phenylalanine, induce positive excessive hyperchromicity (as compared to initial DNA). The correlation between this effect and molecular structures of the substances studied has been shown to exist. An increase of DNA hyperchromicity in the presence of catecholamines has been found to result from the oxygen presence in the aromatic rings of the catecholamines molecules. It is assumed that the interaction between the negative O-atoms in catecholamines and bivalent metal cations in the nucleoprotein complex weakens the DNA-protein binding. This leads to an additional disorientation due to the heat of nucleic acid bases, which were previously bound by the residual protein.
Mol Biol (Mosk)
PMID:[DNA fusion in the presence of catecholamines and substances close to them in structure]. 122 65

1. Six unanaesthetized goats were used to evaluate the effect of liver failure on the hypoxic responsiveness of cerebral blood flow. The animals breathed air and several different hypoxic gas mixtures enriched with sufficient CO2 to maintain an isocapnic state. The cerebral metabolic rate for O2 (CMRo2) was also measured in four of these goats. 2. In baseline studies there was a linear relationship between cerebral blood flow and arterial O2 saturation (Sa,o2) measured at different levels of isocapnic hypoxia. The slopes of the cerebral blood flow/Sa,o2 response lines were used to quantify the response of cerebral blood flow to hypoxia. In the healthy goat, CMRo2 was not depressed by hypoxia until the O2 tension (Po2) in arterial and cerebral venous blood had fallen below critical threshold values of approximately 3-2 and 2-2 kPa (24 and 16 mmHg) respectively. 3. Liver failure was accompanied by a fall in cerebral blood flow and CMRo2. There was also a depression in the response of cerebral blood flow to hypoxia and a disproportionate reduction of cerebral O2 delivery in hypoxia. CMRo2 was further reduced at arterial and cerebral venous Po2 values, which were much higher than the critical threshold values for producing hypoxic CMRo2 depression in health. 4. It is concluded that the brain becomes more vulnerable to the adverse effects of hypoxia during liver failure. This may be of practical importance in the management of patients with arterial hypoxaemia or other complications (e.g. anaemia or shock), which may reduce cerebral oxygen delivery.
Clin Sci Mol Med 1976 Jan
PMID:Effect of liver failure on the cerebral circulatory and metabolic responses to hypoxia in the goat. 124

1. To investigate the interaction of hypoxaemia and blood PCO2 in the production of cerebral hypoxia, we studied six healthy men in whom acute progressive hypoxia was induced by using a rebreathing technique, while the PCO2 was kept constant. 2. At least two blood PCO2 tensions were studied in each subject. Arterial oxygen saturation was monitored continuously by ear oximetry, calibrated for each subject with arterialized blood. The onset of cerebral hypoxia was identified by the appearance of frontal slow waves (less than 5 Hz) in the electroencephalogram (EEG), which was recorded continuously with the bipolar 10-20 electrode placement system. 3. All subjects developed frontal slow waves during at least one experiment: the EEG changes were similar both within and among subjects, irrespective of the blood PCO2 value. 4. The arterial oxygen saturation at which slow-wave activity first occurred showed a significant inverse linear relationship to the PCO2 value at which hypoxia was induced. 5. The results imply that more profound levels of hypoxia are tolerated with high PCO2 values than with normal or low PCO2 values before hypoxic EEG changes become evident. Thus if eucapnia is maintained, EEG changes suggestive of cerebral hypoxia are unlikely to occur if arterial oxygen saturation remains above 75%.
Clin Sci Mol Med 1976 Apr
PMID:Arterial oxygenation and carbon dioxide tensions in the production of hypoxic electroencephalographic changes in man. 126 Dec 11

Hypoxia-ischemia induced by unilateral carotid ligation followed by either 15 (moderate) or 90 (severe) min exposure to 8% oxygen was associated with induction of IGF-BP 2 mRNA expression. A specific rat IGF-BP 2 cDNA probe was used to determine the IGF-BP 2 mRNA distribution in brain sections using in situ hybridization. Untreated control rats and the non-ligated hemisphere in experimental rats expressed IGF-BP 2 mRNA in the choroid plexus, meninges and more weakly in the thalamus, hippocampus and cortical layer 5. Increased expression in experimental rats was limited to regions known to have neuronal damage. Three days after the moderate insult the signal was increased in the CA1/2 region of the hippocampus and thalamus of the ligated side. Three days after the severe insult IGF-BP 2 expression was found surrounding the infarcted regions while by 5 days after severe insult the whole infarcted volume showed induction. The results suggest a role for the IGFs in the post-asphyxial response. IGF-BP 2 may alter the bio-availability of IGF 1 or 2 or modulate their actions in the area of infarction, and thus promote cerebral repair and recovery.
Brain Res Mol Brain Res 1992 Sep
PMID:Expression of insulin-like growth factor-binding protein 2 (IGF-BP 2) following transient hypoxia-ischemia in the infant rat brain. 127 50


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