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J Regnard

Publications and source records attributed to J Regnard.

At least 73 records · Page 4Linked to original sources
PubMed1981

[Measurement of PACO2 in children by capnography and mass spectrometry (author's transl)].

The present study examines the errors of measurement under working conditions using a capnograph and suggests a methodology to obtain optimal results in a given clinical situation. The authors compare the PCO2 measured with the aid of capnograph using CO2 absorption by infrared, with simultaneous measurements of PCO2 using a mass spectrometer as the reference. The observations measured included static and dynamic responses to a step variation of 5% CO2 and also the PACO2 in normal 9 to 12 year old children. The results show that the errors using a capnograph may reach 45 per cent at the highest respiratory frequencies. The influence of the dimensions of the sampling apparatus and the output of the sampling pump on the measurement of PACO2 are discussed. The static and dynamic calibration allow optimal operating conditions for the requirements of a patient in bed. (In this study children aged 9 to 12, with a respiratory frequency of less than 40/min). The errors after achieving optimal conditions is independent of respiratory frequency and always remained less than 5 per cent. A few simple rules are suggested to avoid the errors we have seen and if proper precautions are taken capnography can be considered as a good method for measuring PACO2 in children.

Breath Tests↗
PubMed1975

Renal transplantation and viral infections. II. Results of follow-up studies.

13 renal transplant recipeints were submitted to virological survey over a period of about 10 months following transplantation. They were compared to a group of individuals who underwent no transplantation : 7 patients on chronic hemodialysis and 10 healthy blood donors. The renal transplant recipients, showed rises in titer of antibodies against various viral antigens. Nevertheless, no other viral elimination but that of cytomegalovirus and herpes simplex virus was detected in them. Renal trnasplant recipients show significantly more often rises in virus antibody titers than the other individuals, when time of survey is taken into account. Some of these rises appeared to be simultaneous. Their mechanism is under debate : analysis of special cases and observation of associated immunohematological abnormalities are strongly suggesting that in some situations, rises in titer of viral antibodies may occur without infection.

Adult↗
PubMedDate not supplied

Neural-epithelial cell interplay: in vitro evidence that vagal mediators increase PGE2 production by human nasal epithelial cells.

During inflammatory states, airway epithelial cells are stimulated by various proinflammatory mediators to synthesize paracrine mediators including prostaglandin E2, which likely contributes to the recurrence of allergic inflammation. We studied the effects of acetylcholine (ACh) and substance P (SP) on PGE2 release because these two neuromediators are widely involved in airway inflammation, e.g., to trigger mucosal vasodilation and plasma exudation. PGE2 release was studied at baseline and after addition of ACh and SP (10(-10) to 10(-7) M) in primary cultures of human nasal epithelial cells from control mucosa, inflammatory non-atopic mucosa, and inflammatory atopic mucosa. The mediators' effects on COX 2 mRNA were assessed by Northern blotting. We also tested the effect of atropine and SR140333, inhibitors of ACh and SP, respectively. The spontaneous release of PGE2 was about three times higher in cells from atopic subjects. ACh and SP markedly increased PGE2 release (by more than 1.5 times) and this effect was similar whether the sampled tissues were inflammatory or not. In cells from atopic subjects this neuromediator effect led to a fivefold increase in PGE2 release, as compared to baseline production by cells from control mucosa. This stimulation of PGE2 release by neural mediators was inhibited by specific antagonists. ACh and SP increased COX 2 mRNA in the three groups. Thus, neuromediators can bolster PGE2 production in the airway, likely reinforcing inflammation. In conclusion, these data provide evidence that the interplay of nerve fibers and airway epithelial cells is likely important in inflammatory conditions as, e.g., allergy and asthma.

Acetylcholine↗
PubMedDate not supplied

Acute dysautonomia secondary to autoimmune diseases: efficacy of intravenous immunoglobulin and correlation with a stimulation of plasma norepinephrine levels.

Acute dysautonomia is a disorder characterized by severe sympathetic and parasympathetic failure with relative preservation of motor and sensory function. The disease is considered to be idiopathic in most cases, but there is now a trend towards considering the disorder as an uncommon variant of Guillain Barré syndrome. We report two cases of acute dysautonomia which did not fulfill the criteria of the idiopathic form. The first case was associated with Sjögren's syndrome and the second with thyroiditis and antiganglioside antibodies which were correlated with the severity of the disease. Intravenous gammaglobulin (IVGG) was effective in both cases, as has been reported for the idiopathic form, and in one case the treatment was associated with an increase in the supine and standing plasma norepinephrine levels, thus substantiating the positive effects of IVGG on the orthostatic blood pressure and heart rate. We conclude that the spectrum of acute dysautonomia is superimposable on that of the inflammatory peripheric neuropathies and should include both the idiopathic form and dysautonomia with autoimmune associated disorders. IVGG are effective and seems to act by increasing plasma norepinephrine levels.

Acute Disease↗