Pathologie-biologie
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Pathologie-biologie · Mar 1998
Review[Role of endothelial nitric oxide in the regulation of the vasomotor system].
The arterial wall is structurally and functionally compartmentalized. Each compartment is characterized by a specific cell type and by specific interactions. The endothelial compartment interacts with circulating blood, and the adventitial compartment with the surrounding tissue. ⋯ These phenotype changes may be related to the increase in the oxidative potential of the various types of parietal cells, as suggested by the abnormal presence of inflammatory cells and by the increased expression of inflammation mediators including cyclooxygenase II, inducible NO synthase, and adhesion molecules such as ICAM and VCAM. This model therefore holds promise for elucidating interactions between NO and arteriosclerosis. NO system dysfunction is also seen in other cardiovascular disorders, including congestive heart failure.
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Pathologie-biologie · Jan 1998
Effect of inorganic ions on the oxyhemoglobin dissociation curve of severely ill patients.
We have shown that administration of inorganic potassium phosphates (Pi) to patients with severe diabetic ketoacidosis was able to increase the P50 (the PO2 necessary to achieve a hemoglobin saturation of 50%) by a non diphosphoglycerate (DPG) mediated effect. This suggests that the oxyhemoglobin dissociation curve (ODC) may be determined not only by pH, temperature, CO2 content and DPG but also by plasmatic ions. In order to test this hypothesis we have determined the ODC on whole blood in two groups of subjects, 49 control subjects with matching age and sex and 49 patients suffering from liver cirrhosis, acute pancreatitis, septic shock and acute respiratory distress syndrome. ⋯ In separate experiments we showed that the Bohr effect as expressed in d (log PO2)/dpH amounted to -0.53, -0.46 and -0.42 for SO2 equal to 5%, 50% and 95%, respectively. The corresponding values for the temperature effect was expressed in d (log PO2)/dT amounted to 0.028, 0.024, and 0.020 respectively. The fact that ions play an role in regulating the position of the ODC of patients with ionic disorders may have therapeutical implications, preventive or curative.
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Pathologie-biologie · Nov 1997
Kinetics of chlorhexidine on intact skin following a single application.
Residual chlorhexidine concentrations were measured after application of a single dose on the skin of 22 healthy volunteers. Dosage by high-pressure liquid chromatography in the skin cleansers revealed that the residual concentrations were higher than chlorhexidine MICs for most organisms of the resident skin flora and some responsible for hand-borne infections, even 24 h after application.
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Pathologie-biologie · Apr 1997
Right shift of the oxyhemoglobin dissociation curve in acute respiratory distress syndrome.
Deep hypoxia is known to increase the intraerythrocytic 2,3 diphosphoglycerate (DPG) level and therefore to induce a right shift of the oxyhemoglobin dissociation curve (ODC), which is considered to be a protective mechanism against tissular hypoxia. Our purpose was to assess whether the ODC is shifted to the right in patients with acute respiratory distress syndrome (ARDS) and whether this shift had a beneficial effect on tissue oxygenation. We have determined the whole ODC and related indices in 29 control subjects and 29 patients suffering from ARDS for at least 5 days. ⋯ A right shift decreases therefore the captation of oxygen from the lung. On the other hand theoretical studies have shown that at low arterial PO2 values a right shift of the ODC has a detrimental effect on release of oxygen from hemoglobin if the mixed venous PO2 is decreased. In order to quantify the amount of oxygen actually transmitted to the tissues, others factors are to be investigate as the PCO2 or the temperature.
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Pathologie-biologie · Nov 1995
Randomized Controlled Trial Comparative Study Clinical Trial[Calcium carbasalate-metoclopramide combination versus dihydroergotamine in the treatment of migraine attacks].
In this randomised, double-blind, cross-over study the association of calcium carbasalate+metoclopramide was compared with oral dihydroergotamine mesilate in the treatment of migraine attacks. 155 patients suffering from migraine, with or without aura were analysed; the main efficacy criteria being the evolution of the headache intensity: disappearance of headache 2 hours after administration or incomplete improvement (severe to moderate headache reduced to slight headache). There was a significantly greater reduction in headache intensity following administration of CSC-METO (p < 0.001), the percentage of patients showing recovery or improvement two hours after administration being 64.5% with CSC-METO compared to 43.5% with DHE. A significantly more marked improvement following administration of CSC-METO was also observed for nausea, photophobia, phonophobia, use of analgesic treatment, impact on normal activities and overall assessment by the patient and physician. The frequency of undesirable events was weak and identical for both treatments.