Disease relevance of Partial Pressure

• CONCLUSIONS: Children with diabetic ketoacidosis who have low partial pressures of arterial carbon dioxide and high serum urea nitrogen concentrations at presentation and who are treated with bicarbonate are at increased risk for cerebral edema [1].
• Steady-state initial rates of acetyl-CoA synthesis (upsilon/[E(tot)]) catalyzed by acetyl-CoA synthase from Clostridium thermoaceticum (ACS) were determined at various partial pressures of CO and CO2 [2].
• Hydralazine has been shown to increase minute ventilation, alveolar ventilation, and arterial partial pressure of oxygen (PaO2) after short-term administration in patients with chronic obstructive pulmonary disease and pulmonary hypertension [3].
• Six-month changes in dyspnea score, total lung capacity, thoracic gas volume, FVC, FEV1, diffusing capacity of carbon monoxide, partial pressure of arterial oxygen, oxygen saturation, and alveolar-arterial oxygen gradient were predictive of survival time even after adjustment for baseline values [4].
• Increases in minute phrenic activity and integrated phrenic nerve amplitude (integral Phr) during isocapnic hypoxia (arterial partial pressures of O2, 60, 50 and 40 +/- 1 mmHg) were greater in aged control (n = 15) than hyperoxia-treated rats (n = 11; P < or = 0.01) [5].

Psychiatry related information on Partial Pressure

• During desynchronized sleep ventilation increases and becomes very irregular but the partial pressure of O2 and CO2 in arterial blood is little changed from wakefulness [6].
• This is consistent with the result of catalytic wet air oxidation of phenol and the COD removal can be arrived at 98.2% at temperature 210 degrees C, oxygen partial pressure 3 MPa and reaction time 30 min [7].

High impact information on Partial Pressure

• The mean partial pressure of oxygen in 33 patients was 78 mm Hg at entry and 93 mm Hg after the course of 566C80 (P less than 0.001) [8].
• For example, low 13C/12C in Cretaceous sediments has been attributed to elevated atmospheric (and hence oceanic) CO2 partial pressures [9].
• The response to anaesthetics is completely reversible and saturates at low anaesthetic partial pressures: the half-maximal response for halothane occurs at 0.0063 atm, close to its minimum alveolar concentration (0.0075 atm) in man [10].
• We report on suppression of chemical turbulence by global delayed feedback using, as an example, catalytic carbon monoxide oxidation on a platinum (110) single-crystal surface and carbon monoxide partial pressure as the controlled feedback variable [11].
• Although C4 plant expansions have been recognized in the late Miocene, identification of the underlying causes is complicated by the uncertainties associated with estimates of ancient precipitation, temperature, and partial pressure of atmospheric carbon dioxide (PCO2) [12].

Chemical compound and disease context of Partial Pressure

• In protocol 1, the dose-dependent effects of halothane from 0.5-2.0 minimum alveolar concentration (MAC) on the hypoxic response during moderate hypercapnia (partial pressure of carbon dioxide [PaCO2], 60-65 mmHg) were studied in 10 animals [13].
• The deterioration of cardiovascular compensation for hemorrhage was expressed metabolically by similar decreases in the two groups in partial pressure of oxygen of mixed venous blood and by increases in blood lactate concentration [14].
• Hypoxemia induced significant falls in fetal pH(a), arterial oxygen pressure, acid-base excess, and [HCO(3)(-)], without alteration to arterial partial pressure of carbon dioxide [15].
• Predictors of postoperative complication included postoperative pHi (P = 0.001), gastric luminal partial pressure of carbon dioxide (P = 0.022), and gastric luminal minus arterial partial pressure of carbon dioxide gap (P = 0.013) [16].
• METHODS AND MATERIALS: Oxygen partial pressure (pO2) in rat rhabdomyosarcomas (R1H) was measured sequentially at weekly intervals during a fractionated irradiation with 60Co-gamma-rays (60 Gy/20f/4 weeks) in combination with local hyperthermia (8 f(HT) at 43 degrees C, 1 h/4 weeks) [17].

Biological context of Partial Pressure

• The purpose of this study was to investigate the effect of infusion of 400 mL of red blood cells (RBCs) on 10-km track race time, submaximal heart rate, hematocrit, 2,3-diphosphoglycerate, and partial pressure of oxygen at 50% hemoglobin saturation [18].
• Arterial partial pressure of O2 and CO2 and oxygen consumption remained unchanged during dialysis [19].
• MEASUREMENTS AND MAIN RESULTS: At baseline, for the whole group, forced expiratory volume in 1 second (FEV1) was 1.0 +/- 0.08 L (mean +/- SE); the partial pressure of O2 in arterial blood (PaO2) was 59 +/- 1.2 mm Hg; and the partial pressure of CO2 in arterial blood (PaCO2) was 48.9 +/- 1.2 mm Hg [20].
• All had an arterial blood pH level lower than that expected for the measured partial pressure of arterial carbon dioxide, all had an abnormally large anion gap, and the blood lactate level exceeded 2.8 mmol/liter [21].
• The effects of the partial pressure of oxygen (pO2) on antioxidant efficiency of beta-carotene in inhibiting radical-initiated lipid peroxidation were studied in murine normal and tumor thymocytes [22].

Anatomical context of Partial Pressure

• Neohemocytes are substantially smaller than erythrocytes, contain 15.1 grams per decaliter of hemoglobin, and have a P50 value (the partial pressure of oxygen at which the hemoglobin is half-saturated) of 24.0 torr [23].
• In common duct bile, observed ranges were as follows: pH, 7.37-7.85; CO2 partial pressure (PCO2), 21-32 mmHg; total CO2 concentration ([TCO2]), 16.4-41.4 mM; total bile salt concentration ([TBS]), 16-93 mM; and [Na], 153-192 mM [24].
• To test this hypothesis, we examined the effect of exposure to high partial pressures of O2 or NO2 on the physical state and function of pulmonary endothelial cell plasma membranes [25].
• METHODS: Monkey and dog cerebral arterial strips with endothelium were suspended for isometric tension recording in Ringer-Locke solution aerated with 95% O2-5% CO2 (partial pressure, 570-600 mm Hg) or 95% N2-5% CO2 (approximately 10 mm Hg) [26].
• Within skeletal muscle the extent to which myoglobin desaturates (deoxy-Mb) and the extent of this desaturation in relation to O2 availability provide an endogenous probe for intracellular O2 partial pressure (P(iO2)) [27].

Associations of Partial Pressure with chemical compounds

• Carbon dioxide partial pressure increased from a mean of 27.3 mmHg in common duct bile to greater than 100 mmHg in gallbladder bile at [TBS] = 180 mM, then declined to approximately 36 mmHg as [TBS] increased to greater than 300 mM [24].
• By contrast, nitric oxide (4.5%, 0.0-18.0; 0.0%, 0.0-17.3) and sildenafil (3.3%, 0.0-11.3; 0.0%, 0.0-12.4) maintained V/Q matching, with raised arterial partial pressure of oxygen (14.3 mm Hg, -1.7 to 31.3) noted for sildenafil [28].
• We have measured hemoglobin oxygen uptake vs. the partial pressure of oxygen, with independently controlled activities of chloride and water [29].
• Intravascular oxygen partial pressures were lower in tumors relative to surrounding normal tissue in tamoxifen-treated tumors as compared to placebo-treated tumors [30].
• Peroxyl radical scavenging by beta-carotene in lipid bilayers. Effect of oxygen partial pressure [31].

Gene context of Partial Pressure

• Partial pressure of oxygen (PaO2) levels in the hIL-10 group (6 hr of CIT) were higher than in empty vector and diluent groups (PaO2, 530 +/- 23 vs. 387 +/- 31 and 439 +/- 27 mmHg, respectively, p < 0.05) [32].
• In these patients plasma elastase and serum IL-6 levels subsequently increased while the ratio of arterial partial pressure of oxygen to fraction inspired oxygen decreased, and they developed bilateral lung infiltration on chest radiography on days 3-7 [33].
• In contrast, there was no correlation between MMP-1 and/or MMP-3 expression and impairment in gas exchange, as determined by the ratio of partial pressure of oxygen to fraction of inspired oxygen (Pao(2)/Fio(2)) on the day of BAL sample [34].
• On the other hand, HIF-1alpha cannot be detected above a critical partial pressure of oxygen when it is subjected to rapid ubiquitinylation and proteasomal degradation [35].
• The inhibition of Epo production at low partial pressures of oxygen by carbon monoxide provides evidence that a heme protein is integrally involved in the oxygen-sensing mechanism [36].

Analytical, diagnostic and therapeutic context of Partial Pressure

• Intracellular pH was measured by phosphorus magnetic resonance spectroscopy, and intracellular bicarbonate was calculated using sagittal sinus partial pressure of CO2 during reperfusion [37].
• Blood flow velocity was corrected to 40 mm Hg of end-tidal CO2 partial pressure (PETCO2), and expressed as CV40 [38].
• Dependence of mitochondrial and cytosolic adenine nucleotides on oxygen partial pressure in isolated hepatocytes. Application of a new rapid high pressure filtration technique for fractionation [39].
• Alteration of tissue oxygen partial pressure during isolated, hyperthermic limb perfusion with cytostatic drugs or recombinant human tumor necrosis factor alpha combined with melphalan [40].
• Control of ICP (less than 25 mmHg), hemodynamic values, and blood gas tension (partial pressure of carbon dioxide in arterial blood between 35-38 mmHg) was obtained with propofol infusion (3 mg x kg(-1) x h(-1)) and mechanical ventilation [41].

References