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C Dauphin

Publications and source records attributed to C Dauphin.

31 records · Page 2Linked to original sources
PubMed1997

Non-infectious interstitial alveolitis and foreign body pulmonary vasculitis in a child treated for acute lymphoblastic leukemia.

We report a case of a 14-month-old girl who was treated for acute lymphoblastic leukemia but died from interstitial alveolitis associated with foreign body vasculitis. This respiratory complication arose 3 months after an allogenic bone marrow transplant. No infectious agents (bacteria, virus, or parasite) were isolated from bronchial or lung tissue samples. Respiratory complications after chemotherapy are reviewed as well as the potential origin of the intravascular foreign body.

Antineoplastic Agents↗
PubMed1997

Effects of caffeine on carotid sinus nerve chemosensory discharge in kittens and cats.

Caffeine (C) decreases apneic episodes in premature infants and is thought to stimulate breathing mainly by a central mechanism. While the methylxanthines theophylline and aminophylline are known to alter the carotid chemoreceptor activity, there are little data on C. The aim of the study was to examine the effects of C on the carotid sinus nerve discharge (CSND) in developing animals. Nine kittens 17-21 days old and six adult cats that were anesthetized and artificially ventilated were studied. They received four consecutive doses of C, each of 10 mg/kg, administered at intervals of 20 min either as intravenous bolus injection (6 kittens, 3 cats) or continuous infusion (3 kittens, 3 cats). Bolus injections of C invariably induced a prompt but transient increase in the CSND from 4.1 +/- 0.6 to 8.1 +/- 1.0 (SE) impulses/s in kittens (P = 0.01) and form 3.9 +/- 0.1 to 7.9 to 1.0 impulses/s in cats (after the first injection). This response was associated with a significant decrease in arterial blood pressure. Continuous infusion of C did not induce any early change in either CSND or blood pressure in kittens or cats. Fifteen minutes after C injection or infusion was begun, CSND values in air, 8% O2-balance N2, or 100% O2 were not significantly different from control. Haloperidol administered at the end of the experiment in four cats and four kittens significantly increased CSND and did not suppress the early response to C injection. It is concluded that caffeine administered by bolus in the kitten induces a transient stimulation of the CSND that is associated with a decrease in the arterial blood pressure and is independent of the dopaminergic mechanisms in the carotid body. The lack of sustained effect implies the main mechanism to the ventilatory stimulation by C must be central.

Animals↗
PubMed1997

[Evaluation of sevoflurane, new anesthetic agent during pediatric cardiac catheterization].

General anaesthesia for cardiac catheterisation of children is a real challenge for anaesthetists. The recent commercialisation of sevoflurane, a new halogenated anaesthetic agent allowing induction by inhalation with an extremely rapid loss of consciousness and recovery with minimal cardiovascular effects, incited the authors to evaluate its use in this indication. Forty children aged 4 months to 10 years undergoing cardiac catheterisation were anaesthetised with a standardised protocol with sevoflurane. An anaesthetic state was obtained in 34 +/- 8 seconds with excellent tolerance, few and transient secondary effects. Changes in respiratory and haemodynamic status during catheterisation were only significant in 5 children with associated pulmonary disease and who developed desaturation requiring oxygen therapy. The recovery times were 6.3 +/- 2.1 minutes for ablation of the laryngeal mask, 7.1 +/- 3.5 minutes to the first cry and 8.4 +/- 3.8 minutes to opening of the eyes. All children were fit for discharge from the post-catheterisation observation ward after an average of 12.5 +/- 4.3 minutes. The most distressing secondary effect on recovery was headache, experienced by 4 children. Sevoflurane would seem to be particularly useful for general anaesthesia for diagnostic or interventional cardiac catheterisation of children.

Anesthesia, General↗
PubMed1997

[Evaluation of cardiac risk before vascular surgery by dobutamine stress echocardiography].

The detection of coronary artery disease is essential before abdominal aortic surgery. In view of the limitations of the usual methods of investigation, dobutamine stress echocardiography was assessed in this indication. Eighty-five patients with an aortic abdominal aneurysm or obstructive arterial disease underwent dobutamine stress echocardiography followed by coronary angiography. Depending on the results, vascular surgery was performed directly, after myocardial revascularisation or not at all. Significant coronary lesions (stenosis > or = 50%) were found in 32 of the 85 patients (38%). Dobutamine stress echocardiography had a sensitivity of 78% and a specificity of 75%, and positive and negative predictive values of 66 and 85% respectively. The relative risk of coronary disease was 4.4. In this series, 15 patients had severe coronary lesions: 2 were turned down for surgery and 13 underwent myocardial revascularisation; 14 of them (93%) had a positive stress echo. The only 2 non-fatal cardiac complications of peripheral surgery (3%) occurred after a positive dobutamine stress echo. This study confirms both the necessity of preoperative assessment of coronary risk and the efficacy of dobutamine stress echocardiography in this indication. Dobutamine stress echocardiography is reliable, non-invasive, economical and a real alternative to isotopic methods. Its good predictive value justifies using coronary angiography only for patients with a positive result.

Adult↗
PubMed1996

Expression of dopamine D2-receptor mRNA isoforms at the peripheral chemoreflex afferent pathway in developing rabbits.

The two isoforms of dopamine D2 receptor, D2 short (D2s) and D2 long, are generated by alternative splicing of premessenger RNA and differ in the length of their third cytoplasmic loop. Expression of these two isoforms has not yet been studied at the level of the peripheral arterial chemoreflex pathway. Using reverse transcriptase-polymerase chain reaction, we evaluated the relative abundance of dopamine D2 receptor mRNA by amplifying a common segment between both D2 receptor mRNA isoforms which reflects the total D2-receptor mRNA and the two isoforms in the carotid bodies, the petrosal ganglia, and the superior cervical ganglia of 1-, 10-, and 25-day-old and adult rabbits, GH4C1 cell line, which does not express D2 receptors, was used as negative control, whereas GH4C1 19 cell line, which expresses only the D2s mRNA and the striatum of each age, were used as positive controls. Both D2-receptor mRNA isoforms were found to be expressed in all organs studied of newborn and adult rabbits. The expression of total D2 receptor mRNA in 10- and 25-day-old and adult rabbits was found to be 3-, 5-, and 1.5-fold more, respectively, compared with 1-day-old rabbits for all organs studied. Our data suggest that the expression of D2-receptor mRNA is modulated with age at the level of the peripheral arterial chemoreflex pathway.

Afferent Pathways↗
PubMed1993

[Use of 7-amino-4-methylcoumarin for the spectrophotometric determination of nitrites].

A new reagent of diazotisation, 7-amino-4-methylcoumarin (coumarin 120) is proposed for the spectrophotometric determination of small amounts of nitrite. To obtain molecules with an high absorptivity, the copulation with different aromatic amines is studied. N, N-dimethylaniline leads to the best results, particularly the reproducibility. Under the optimised conditions, a good linearity (between 10 micrograms/l and 200 micrograms/l) and a good reproducibility (2-3%) according to the amount of detected nitrites are obtained.

Amines↗
PubMed1992

Effects of adrenalectomy and glucocorticoids on rat brain dopamine receptors.

The effects of adrenalectomy (ADX) and dexamethasone (DEX) treatment on brain dopamine (DA) receptors of ovariectomized (OVX) rats were investigated by autoradiography using binding of the D1 and D2 antagonists ligands [3H]SCH 23390 and [3H]spiperone, respectively. Fourteen days after ADX, D1 receptors decreased in the middle striatum (M.CPu) and in the dorsal area of the posterior striatum (P.CPu). A more pronounced decrease was observed in the substantia nigra (SN) and no significant changes occurred in the anterior striatum (A.CPu), globus pallidus (GP) and accumbens (Acb). D2 receptors decreased in the M.CPu and dorsal area of the P.CPu and remained unchanged in the A.CPu as compared to OVX rats. Twenty-eight days after ADX, D1 and D2 receptors decreased in the A.CPu (D2), in the M.CPu (D2) and substantially in the SN (D1). DEX treatment (14 days, 0.5 mg/kg, b.i.d., IM, starting 14 days after ADX) reversed these effects in the A.CPu (D2), M.CPu (D2) and SN (D1) when compared to ADX+OVX rats. DEX also increased the density of D1 receptors in Acb, A.CPu and M.CPu when compared to OVX rats. Striatal homogenates of rats treated chronically with ACTH and corticosterone had an increased density of D1 receptors while these treatments alone left these receptors unchanged, thus suggesting either a minor role or no role of the changes in ACTH levels following glucocorticoids manipulations. Our results suggest that the adrenals play a role in the modulation of DA receptors activity in the rat brain.

Adrenalectomy↗