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1.
Arch Pediatr ; 23(2): 188-91, 2016 Feb.
Article in French | MEDLINE | ID: mdl-26727156

ABSTRACT

INTRODUCTION: Cat scratch disease is an infection caused by Bartonella henselae. The main clinical form is a lymphadenopathy with fever. However, uncommon bone involvement has been described. CASE REPORT: In this paper, we report a case of osteomyelitis in a 13-year-old teenager infected with B. henselae. The diagnosis was made based on PCR only because the serology was negative. A literature review reports 65 cases of osteomyelitis due to cat scratch disease. For each case, serology and PCR were notified. CONCLUSION: Osteomyelitis caused by B. henselae is a rare clinical manifestation. The diagnosis can be difficult, but the medical history must be accurate to search for contact with a cat and a cat scratch.


Subject(s)
Cat-Scratch Disease , Osteomyelitis/microbiology , Adolescent , Female , Humans
2.
Diagn Interv Imaging ; 95(9): 825-31, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24746759

ABSTRACT

PURPOSE: To assess clinical outcomes of blunt splenic injuries (BSI) managed with proximal versus distal versus combined splenic artery embolization (SAE). MATERIALS AND METHODS: All consecutive patients with BSI admitted to our trauma centre from 2005 to 2010 and managed with SAE were reviewed. Outcomes were compared between proximal (P), distal (D) or combined (C) embolization. We focused on embolization failure (splenectomy), every adverse events occurring during follow up and material used for embolization. RESULTS: Fifty patients were reviewed (P n = 18, 36%; D n = 22, 44%; C n = 8, 16%). Mean injury severity score was 20. The technical success rate was 98%. Four patients required splenectomy (P n = 1, D n = 3, C n = 0). Clinical success rate for haemostasis was 92% (4 re-bleeds: P n = 2, D n = 2, C n = 0). Outcomes were not statistically different between the materials used. Adverse events occurred in 65% of the patients during follow up. Four percent of the patients developed major complications and 56% developed minor complications attributable to embolization. There was no significant difference between the 3 groups. CONCLUSION: SAE had an excellent success rate with adverse events occurring in 65% of the patients and no significant differences found between the embolization techniques used. Proximal preventive embolization appears to protect in high-grade traumatic injuries.


Subject(s)
Embolization, Therapeutic/methods , Splenic Artery , Splenic Rupture/therapy , Wounds, Nonpenetrating/therapy , Adolescent , Adult , Aged , Angiography , Child , Combined Modality Therapy , Embolization, Therapeutic/adverse effects , Female , France , Humans , Male , Middle Aged , Retrospective Studies , Splenectomy , Splenic Rupture/diagnosis , Treatment Outcome , Young Adult
3.
JBR-BTR ; 96(3): 112-7, 2013.
Article in English | MEDLINE | ID: mdl-23971165

ABSTRACT

The present manuscript is a summary of two lectures which were given respectively by B. Weynand and G.R. Ferretti. The new classification of lung adenocarcinomas has changed the view of the radiologists and the pathologists especially regarding the former bronchiolo-alveolar carcinoma (BAC). The aim of this paper is to correlate radiological and histopathological images according to the 2011 classification for lung adenocarcinoma proposed by the International Association for the Study of Lung cancer, the American Thoracic Society and the European Respiratory Society and to draw attention to the way these lesions can be approached preoperatively.


Subject(s)
Adenocarcinoma/diagnosis , Lung Neoplasms/diagnosis , Positron-Emission Tomography/trends , Tomography, X-Ray Computed/trends , Adenocarcinoma/classification , Humans , Lung Neoplasms/classification
4.
Article in English | MEDLINE | ID: mdl-22538405

ABSTRACT

Patients with cystic fibrosis (CF) often suffer from gastrointestinal cramps and intestinal obstruction. The CF transmembrane conductance regulator (CFTR) channel has been shown to be expressed in vascular and airway smooth muscle (SM). We hypothesized that the absence of CFTR expression alters the gastrointestinal SM function and that these alterations may show strain-related differences in the mouse. The aim of this study was to measure the contractile properties of the ileal SM in two CF mouse models. CFTR(-/-) and CFTR(+/+) mice were studied on BALB/cJ and C57BL/6J backgrounds. Responsiveness of ileal strips to electrical field stimulation (EFS), methacholine (MCh), and isoproterenol was measured. The mass and the cell density of SM layers were measured morphometrically. Finally, the maximal velocity of shortening (Vmax) and the expression of the fast (+)insert myosin isoform were measured in the C57BL/6J ileum. Ileal hyperreactivity was observed in response to EFS and MCh in CFTR(-/-) compared with CFTR(+/+) mice in C57BL/6J background. This latter observation was not reproduced by acute inhibition of CFTR with CFTR(inh)172. BALB/cJ CFTR(-/-) mice exhibited a significant increase of SM mass with a lower density of cells compared with CFTR(+/+), whereas no difference was observed in the C57BL/6J background. In addition, in this latter strain, ileal strips from CFTR(-/-) exhibited a significant increase in Vmax compared with control and expressed a greater proportion of the fast (+)insert SM myosin isoform with respect to total myosin. BALB/cJ CFTR(-/-) ilium had a greater relaxation to isoproterenol than the CFTR(+/+) mice when precontracted with EFS, but no difference was observed in response to exogeneous MCh. In vivo, the lack of CFTR expression induces a different SM ileal phenotype in different mouse strains, supporting the importance of modifier genes in determining intestinal SM properties.


Subject(s)
Cystic Fibrosis/pathology , Ileum/pathology , Muscle, Smooth/pathology , Adrenergic beta-2 Receptor Agonists/pharmacology , Animals , Blotting, Western , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/physiology , Electric Stimulation , In Vitro Techniques , Isoproterenol/pharmacology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Muscarinic Agonists/pharmacology , Muscle Contraction/drug effects , Muscle Tonus/drug effects , Myosin Heavy Chains/metabolism
5.
J Radiol ; 91(5 Pt 2): 657-63, 2010 May.
Article in French | MEDLINE | ID: mdl-20657372

ABSTRACT

Follow-up after thoracic aortic repair relies on CT and MR imaging in order to detect complications from the treatment or underlying pathology. Following prosthetic repair of the ascending aorta, peri-prosthetic hematoma and anastomotic complications (leak, false aneurysm, peri-prosthetic circulation) should be excluded. Following treatment with a covered stent, the location of the prosthesis and its skeleton should be evaluated and endo-leaks and wall defects should be excluded. Following treatment of a dissection, there often is persistent flow in the false lumen. The entry points into the false lumen should be identified. The caliber of the aorta at different levels should be assessed. Signs of ischemia (static and dynamic) and acute complications should be excluded in patients with acute chest pain. Atherosclerosis and dysplastic conditions may affect other segments of the aorta (aneurysm, dissection, hematoma). Follow-up is performed with CT, if possible, when high-resolution evaluation is required, of with MRI in other cases. Follow-up is obtained on a yearly basis or twice a year when an evolutive process is identified. It is performed every two to five years when the risk is low. Follow-up should be suggested by the radiologist.


Subject(s)
Aorta, Thoracic/surgery , Aortic Diseases/diagnosis , Magnetic Resonance Imaging , Postoperative Complications/diagnosis , Tomography, X-Ray Computed , Aged , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/pathology , Female , Humans
6.
Clin Exp Allergy ; 39(7): 1018-26, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19364333

ABSTRACT

BACKGROUND: The remodelling of airway smooth muscle (ASM) associated with asthma severity may involve the migration of ASM cells towards the epithelium. However, little is known about the mechanisms of cell migration and the effect of epithelial-derived mediators on this process. OBJECTIVE: The main objective of the current study is to assess the effects of epithelial-derived chemokines on ASM cell migration. METHODS: Normal human ASM cells were incubated with supernatants from cells of the bronchial epithelial cell line BEAS-2B and normal human bronchial epithelial (NHBE) cells. To induce chemokine production, epithelial cells were treated with TNF-alpha. Chemokine expression by epithelial cells was evaluated by quantitative real-time PCR, ELISA and membrane antibody array. To identify the role of individual chemokines in ASM cell migration, we performed migration assays with a modified Boyden chamber using specific neutralizing antibodies to block chemokine effects. RESULTS: Supernatants from BEAS-2B cells treated with TNF-alpha increased ASM cell migration; migration was increased 1.6 and 2.5-fold by supernatant from BEAS-2B cells treated with 10 and 100 ng/mL TNF-alpha, respectively. Protein levels in supernatants and mRNA expression by BEAS-2B cells of regulated on activation, normal T cell expressed and secreted (RANTES) and IL-8 were significantly increased by 100 ng/mL TNF-alpha treatment. The incubation of supernatant with antibodies to RANTES or IL-8 significantly reduced ASM cell migration, and the combined antibodies further inhibited the cell migration. The migratory effects of supernatants and inhibiting effects of RANTES and/or IL-8 were confirmed also using NHBE cells. CONCLUSION: The results show that chemokines from airway epithelial cells cause ASM cell migration and might potentially play a role in the process of airway remodelling in asthma.


Subject(s)
Bronchi/cytology , Cell Movement , Chemokines/metabolism , Epithelium/metabolism , Muscle, Smooth/cytology , Bronchi/immunology , Cells, Cultured , Chemokine CCL5/immunology , Chemokine CCL5/metabolism , Epithelium/immunology , Humans , Interleukin-8/immunology , Interleukin-8/metabolism , Muscle, Smooth/immunology , Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/metabolism
7.
J Appl Physiol (1985) ; 94(4): 1403-9, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12626471

ABSTRACT

Although it is well known that hypoxemia induces pulmonary vasoconstriction and vascular remodeling, due to the proliferation of both vascular smooth muscle cells and fibroblasts, the effects of hypoxemia on airway smooth muscle cells are not well characterized. The present study was designed to assess the in vitro effects of hypoxia (1 or 3% O(2)) on rat airway smooth muscle cell growth and response to mitogens (PDGF and 5-HT). Cell growth was assessed by cell counting and cell cycle analysis. Compared with normoxia (21% O(2)), there was a 42.2% increase in the rate of proliferation of cells exposed to 3% O(2) (72 h, P = 0.006), as well as an enhanced response to PDGF (13.9% increase; P = 0.023) and to 5-HT (17.2% increase; P = 0.039). Exposure to 1% O(2) (72 h) decreased cell proliferation by 21.0% (P = 0.017) and reduced the increase in cell proliferation induced by PGDF and 5-HT by 16.2 and 15.7%, respectively (P = 0.019 and P = 0.011). A significant inhibition in hypoxia-induced cell proliferation was observed after the administration of bisindolylmaleimide GF-109203X (a specific PKC inhibitor) or downregulation of PKC with PMA. Pretreatment with GF-109203X decreased proliferation by 21.5% (P = 0.004) and PMA by 31.5% (P = 0.005). These results show that hypoxia induces airway smooth muscle cell proliferation, which is at least partially dependent on PKC activation. They suggest that hypoxia could contribute to airway remodeling in patients suffering from chronic, severe respiratory diseases.


Subject(s)
Hypoxia/pathology , Muscle, Smooth/pathology , Trachea/pathology , Animals , Becaplermin , Cell Cycle , Cell Division/drug effects , Cells, Cultured , Enzyme Inhibitors/pharmacology , Hypoxia/enzymology , Indoles/pharmacology , Male , Maleimides/pharmacology , Platelet-Derived Growth Factor/pharmacology , Protein Kinase C/antagonists & inhibitors , Proto-Oncogene Proteins c-sis , Rats , Rats, Inbred F344 , Serotonin/pharmacology , Trachea/enzymology
8.
Am J Respir Cell Mol Biol ; 21(1): 30-6, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10385590

ABSTRACT

The effects of concomitant P1-receptor stimulation on peak intracellular Ca2+ release by extracellular adenosine 5'-triphosphate (ATP) and 5-hydroxytryptamine (5-HT) were investigated in cultured airway smooth-muscle (ASM) cells. The results show that peak Ca2+ release to ATP is enhanced by preincubation with adenosine (ADO) and with the specific A3 receptor agonist 1-Deoxy-1-(6-([(3-iodophenyl)methyl] amino)-9H-purin-9-yl)-N-methyl-beta-D-ribofuranuronamide (1B-MECA). The response to 5-HT, a smooth-muscle contractile agonist, was also enhanced after preincubation with ADO. Further measurements showed that this enhancement of the response to ATP was dependent on extracellular calcium because it was abolished by the removal of Ca2+ from the extracellular fluid and by incubation with the calcium channel blocker nifedipine. In addition, there was no difference between the levels of total inositol phosphates measured in the presence of ATP alone or of ADO + ATP. AACOCF3, a specific blocker of phospholipase A2, decreased the peak Ca2+ response to ATP and abolished the enhanced response to ATP and 5-HT produced by ADO. We conclude that stimulation of P1 and P2 receptors in ASM cells activates not only phospholipase C but also phospholipase A2. The enhancement of ATP-induced and 5-HT-induced Ca2+ release is due to Ca2+ influx from the extracellular fluid through a Ca2+ channel presumably modulated by arachidonic acid. These data show that endogenous ADO may modulate airway hyperresponsiveness by enhancing the ASM response to contractile agonists.


Subject(s)
Adenosine Triphosphate/pharmacology , Adenosine/pharmacology , Calcium/metabolism , Muscle, Smooth/drug effects , Trachea/drug effects , Animals , Arachidonic Acids/pharmacology , Cells, Cultured , Dose-Response Relationship, Drug , Drug Synergism , Enzyme Inhibitors/pharmacology , Muscle, Smooth/metabolism , Nifedipine/pharmacology , Rats , Rats, Inbred F344 , Serotonin/metabolism
9.
Am J Respir Cell Mol Biol ; 16(2): 199-205, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9032128

ABSTRACT

Extracellular adenosine triphosphate (ATP) has a range of effects on a wide variety of cells through the activation of specific purinoceptors. The aim of this study was to establish whether P2 purinoceptors are present on airway smooth muscle cells. Experiments were conducted on cultured rat tracheal smooth-muscle cells (first through third passage). Intracellular Ca2+ ([Ca2+]i) was measured using Fura-2 and dual-excitation wavelength microfluorometry. The effects of ATP, adenosine diphosphate (ADP), uridine triphosphate (UTP), and adenosine (ADO) were measured in concentrations from 10(-6) to 10(-3) M. At a concentration of 10(-4) M, the peak [Ca2+]i was 502 +/- 92 nM for ATP and 543 +/- 76 nM for UTP (mean +/- standard error of the mean). ADO had no significant effect on Ca2+ release. Peak [Ca2+]i induced by ATP was not dependent on extracellular Ca2+ but was blocked by U-73122, an inhibitor of phospholipase C. Pretreatment with adenosine deaminase and desensitization with alphabeta-MeATP had no effect on ATP-induced Ca2+ release. The effects of ATP (10(-4) M) on peak [Ca2+]i were potentiated by the presence of ADO 10(-5) M (969 +/- 257 nM; P < 0.05). The presence of XAC, a blocker of A1 and A2 ADO receptors did not prevent this effect. In the presence of XAC, ADO 10(-6) M potentiated the effects of ATP (peak [Ca2+]i: 1,300 +/- 229 nM). The addition of 1433U83, a blocker of A3 ADO receptors, blocked the synergistic effect of ADO 10(-6) M on ATP. These data show that P2 purinoceptors, most likely of the P2U subtype, are present on airway smooth muscle cells and that the newly discovered A3 ADO receptor appears to be also present.


Subject(s)
Calcium/metabolism , Purine Nucleosides/pharmacology , Purine Nucleotides/pharmacology , Trachea/drug effects , Animals , Cytosol/drug effects , Cytosol/metabolism , Male , Muscle, Smooth/cytology , Muscle, Smooth/drug effects , Muscle, Smooth/metabolism , Rats , Rats, Inbred F344 , Receptors, Purinergic P2/metabolism , Trachea/cytology , Trachea/metabolism
10.
Obstet Gynecol ; 86(5): 744-8, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7566841

ABSTRACT

OBJECTIVE: To assess the etiologic role of maternal short stature, low pre-pregnancy body mass index (BMI), and low rate of gestational weight gain in idiopathic preterm labor. METHODS: We carried out a three-center case-control study of 555 women with idiopathic onset of preterm labor (before 37 completed weeks), including two overlapping (ie, nonmutually exclusive) subsamples: cases with early preterm labor (before 34 completed weeks) and cases with recurrent preterm labor (before 37 completed weeks plus a history of prior preterm delivery or second-trimester miscarriage). Controls were matched to cases by race and smoking history. All subjects responded in person to questions about height, pre-pregnancy weight, gestational weight gain, and obstetric and sociodemographic histories. RESULTS: Maternal height, pre-pregnancy weight, and gestational weight gain demonstrated excellent test-retest reliability, with intra-class correlation coefficients of 0.97, 0.99, and 0.91, respectively. Based on matched analyses, women with a height of 157.5 cm or less had an increased risk of idiopathic preterm labor (odds ratio [OR] 1.85, 95% confidence interval [CI] 1.25-2.74), as did those with a pre-pregnancy BMI less than 19.8 kg/m2 (OR 1.63, 95% CI 1.09-2.44) or a gestational weight gain rate less than 0.27 kg/week (OR 1.74, 95% CI 1.16-2.62). Conditional logistic regression models containing all three anthropometric variables and controlling for parity, marital status, language, age, and education yielded virtually identical point estimates and CIs. CONCLUSION: Maternal short stature, low pre-pregnancy BMI, and low rate of gestational weight gain may lead to shortened gestation by increasing the risk of idiopathic preterm labor.


Subject(s)
Body Constitution , Obstetric Labor, Premature/etiology , Anthropometry , Body Height , Body Mass Index , Body Weight , Case-Control Studies , Confidence Intervals , Female , Humans , Maternal Age , Odds Ratio , Pregnancy , Risk Factors , Weight Gain
11.
Am J Epidemiol ; 142(10): 1078-88, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7485053

ABSTRACT

Previous studies suggest that women with asthma are at increased risk of preterm birth. Moreover, drugs (especially beta-agonists) used to treat asthma are also used to treat preterm labor. The authors carried out a case-control study of 555 women from three hospital centers with idiopathic preterm labor (< 37 weeks), including two overlapping (i.e., non-mutually exclusive) subsamples: cases with early idiopathic preterm labor (< 34 weeks) and cases with idiopathic recurrent preterm labor (< 37 weeks plus a previous history of preterm delivery or second-trimester miscarriage). Controls were matched to cases according to race and smoking history prior to and during pregnancy. All subjects responded in person to questions about atopic, respiratory, obstetric, and sociodemographic histories. Subjects in the early and recurrent preterm labor subsamples were also asked to undergo spirometric testing with methacholine challenge 6-12 weeks after delivery. Cases were significantly more likely to report histories of asthma symptoms and physician-diagnosed asthma (matched odds ratios of 2-3) than controls, particularly those cases with recurrent preterm labor. No significant associations were observed, however, with methacholine responsiveness. These results could not be explained by residual confounding by smoking or other variables, nor by selective recall of asthma symptoms and histories by cases. Women with asthma are at increased risk of idiopathic preterm labor. The fact that no such association was seen with methacholine responsiveness suggests that nonatopic, noncholinergic mechanisms may link bronchial and uterine smooth muscle lability.


Subject(s)
Asthma/complications , Obstetric Labor, Premature/etiology , Pregnancy Complications , Adult , Asthma/drug therapy , Asthma/physiopathology , Bronchial Hyperreactivity/physiopathology , Bronchial Provocation Tests , Case-Control Studies , Female , Forced Expiratory Volume , Humans , Hypersensitivity/diagnosis , Medical History Taking , Methacholine Chloride , Pregnancy , Spirometry
12.
Br J Clin Pharmacol ; 40(4): 319-24, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8554933

ABSTRACT

1. To test whether cystic fibrosis (CF) altered the kinetics and dynamics of oral salbutamol, 11 patients with CF (19-33 years old; five females; FEV1: 37 +/- 12% of predicted value) and 10 healthy volunteers (20-41 years old; five females; FEV1: 99 +/- 14% of predicted value) received orally 4 mg salbutamol. 2. The estimated pharmacokinetic parameters of salbutamol in patients with CF were identical to those in healthy subjects. For instance, peak plasma concentrations of salbutamol were 10.5 +/- 2.6 (mean +/- s.d.) and 10.2 +/- 2.9 ng ml-1 (NS), and the area under salbutamol plasma concentrations as a function of time (AUC (0, 7 h)) was 43.0 +/- 9.3 ng ml-1 h and 43.3 +/- 12.7 ng ml-1 h (NS) in CF patients and in healthy subjects, respectively. Since on a mg kg-1 dose basis, CF patients received a dose 28% greater than healthy subjects, this lack of differences implies a decrease in the amount of salbutamol absorbed, or alternatively, an increase in both clearance and volume of distribution of salbutamol. 3. Salbutamol did not elicit bronchodilation in CF patients, but increased heart rate from 77 +/- 2 to 103 +/- 3 beats min-1 (P < 0.05). 4. Salbutamol decreased plasma potassium concentrations from 4.5 +/- 0.1 to 3.8 +/- 0.1 mmol l-1 in the CF group (P < 0.05) and from 4.1 +/- 0.2 to 3.4 +/- 0.1 mmol l-1 in the controls (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Adrenergic beta-Agonists/blood , Albuterol/blood , Bronchodilator Agents/blood , Cystic Fibrosis/blood , Administration, Oral , Adrenergic beta-Agonists/pharmacokinetics , Adrenergic beta-Agonists/pharmacology , Adult , Albuterol/pharmacokinetics , Albuterol/pharmacology , Bronchodilator Agents/pharmacokinetics , Bronchodilator Agents/pharmacology , Female , Heart Rate/drug effects , Humans , Male , Potassium/blood , Respiratory Function Tests
13.
Peptides ; 16(4): 653-6, 1995.
Article in English | MEDLINE | ID: mdl-7479299

ABSTRACT

The aim of this work was to establish the role of endogeneous ANP during a spontaneous asthma attack. Forced expiratory lung volume in 1 s (FEV1), cardiovascular parameters, and plasma ANP, cAMP, and cGMP were measured for 60 min before and 10 min after treatment with a bronchodilator in 10 asthmatics. The results show that in the presence of moderate bronchoconstriction, FEV1 was 54 +/- 3% (+/-SE); ANP levels initially were slightly elevated at 47 +/- 10 pg/ml and decreased to 26 +/- 3 pg/ml (p < 0.05) over 60 min, with no change in FEV1. Following salbutamol inhalation, FEV1 increased to 77 +/- 4% with no change in ANP. We conclude that endogenous ANP does not act as a bronchodilator in asthmatics with moderate bronchospasm.


Subject(s)
Albuterol/therapeutic use , Asthma/blood , Atrial Natriuretic Factor/blood , Bronchi/physiopathology , Acute Disease , Adult , Analysis of Variance , Asthma/drug therapy , Asthma/physiopathology , Atrial Natriuretic Factor/physiology , Female , Humans , Male
14.
Peptides ; 15(4): 719-21, 1994.
Article in English | MEDLINE | ID: mdl-7937352

ABSTRACT

The aim of this work was to establish whether a physiological increase in atrial natriuretic peptide (ANP) plasma levels affects pulmonary gas exchange in humans. Ten volunteers received an infusion of either ANP (4 pmol.kg-1.min-1) or physiological saline, for 60 min. Baseline measures of the alveolar-arterial PO2 difference and of the physiological dead space were within normal limits and remained stable during and after the infusion of ANP or saline, although plasma ANP and cGMP rose significantly (p < 0.01) (mean +/- SEM: ANP: 13.4 +/- 3.9 to 56.0 +/- 10.4 pmol/l; cyclic GMP: 3.8 +/- 0.3 to 17.0 +/- 3.8 nmol/l). We conclude that a physiological increase in plasma ANP does not affect pulmonary gas exchange significantly in humans.


Subject(s)
Atrial Natriuretic Factor/physiology , Pulmonary Gas Exchange , Adult , Humans , Infusions, Intravenous , Male , Reference Values , Single-Blind Method
15.
Rev Mal Respir ; 11(2): 131-40, 1994.
Article in French | MEDLINE | ID: mdl-8202604

ABSTRACT

Over the last fifty years, the role of neurogenic factors in asthma and bronchial hyperreactivity has been intensively investigated. The roles of the cholinergic and adrenergic nervous systems have been clarified and several sub-types of muscarinic receptors identified. The localisation and functions of both muscarinic and adrenergic receptors have been further specified. It has also been shown that afferent nerve fibers as well as sympathetic and parasympathetic nerve fibers secrete various neuropeptides. The physiological role of these peptides is not yet known but it appears that they have a powerful effect on bronchial smooth muscle tone, microvascular permeability, mucus secretion and secretion of mediators by inflammatory cells. The results of numerous studies suggest that there are several abnormalities in the adrenergic and cholinergic nervous systems of asthmatic patients, but that these abnormalities are not themselves the cause of bronchial hyperreactivity. They may however contribute to enhance it. The role of the various newly identified neuropeptides in the genesis and maintenance of bronchial hyperreactivity remains to be determined.


Subject(s)
Asthma/physiopathology , Autonomic Nervous System/physiopathology , Bronchial Hyperreactivity/physiopathology , Adrenergic Fibers/physiology , Afferent Pathways/physiopathology , Asthma/immunology , Bronchial Hyperreactivity/immunology , Capillary Permeability/physiology , Cholinergic Fibers/physiology , Humans , Inflammation , Mucus/metabolism , Muscle, Smooth/physiopathology , Neuropeptides/metabolism , Receptors, Adrenergic/physiology , Receptors, Muscarinic/classification , Receptors, Muscarinic/physiology
16.
Peptides ; 14(6): 1325-30, 1993.
Article in English | MEDLINE | ID: mdl-8134314

ABSTRACT

The effect of atrial natriuretic peptide (ANP) on histamine-induced bronchoconstriction was studied in vivo (in normoxic and in hypoxic rabbits) and in vitro. Thirty-two anesthetized rabbits, spontaneously breathing room air or 10% O2, received infusions of ANP (20, 40, or 80 ng/min/kg normoxia; 20 ng/min/kg hypoxia) or the vehicle for 100 min. After 75 min of ANP infusion, bronchoconstriction was induced inhaling histamine; respiratory resistance (Rrs) was measured prior to and until 20 min posthistamine. The results show that the histamine-induced increase in Rrs was significantly reduced by ANP 80 ng/kg/min in normoxia, and by ANP 20 ng/kg/min in hypoxia. In vitro, ANP had no effect on tracheal and bronchial smooth muscle precontracted with histamine or acetylcholine. These results show that ANP can decrease a histamine-induced bronchoconstriction in vivo but not in vitro, suggesting an indirect mechanism of action.


Subject(s)
Airway Resistance/drug effects , Asthma/drug therapy , Atrial Natriuretic Factor/pharmacology , Bronchodilator Agents/pharmacology , Anesthetics , Animals , Atrial Natriuretic Factor/blood , Bronchodilator Agents/blood , Disease Models, Animal , In Vitro Techniques , Male , Oxygen/pharmacology , Rabbits
17.
Br J Pharmacol ; 110(2): 804-8, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8242254

ABSTRACT

1. The aim of the present work was to investigate under which circumstances atrial natriuretic peptide (ANP) modulates airway resistance. 2. Of the six groups of rabbits (n = 5) studied, three received an infusion of ANP (80 ng min-1 kg-1 i.v.) for a period of 100 min, while the other three were infused with the vehicle. Before receiving the infusion of ANP or the vehicle, the animals were pretreated with atropine (0.5 mg kg-1 i.v.), propranolol (2 mg kg-1 i.v.) or not pretreated. After 75 min of infusion of ANP, bronchoconstriction was induced by inhalation of histamine. Respiratory resistance (Rrs) was measured before and 3, 5, 10, 15 and 20 min post-histamine challenge. 3. Following 75 min of ANP infusion, plasma ANP concentration increased from 153 +/- 52 (mean +/- s.e.mean) to 1441 +/- 203 pg ml-1 (P < 0.05) without affecting baseline Rrs. Control Rrs values (12.5-20.4 cmH2O l-1 s) were significantly increased following the inhalation of histamine (P < 0.001). By themselves, atropine, propranolol or ANP did not modify the histamine-induced increase in Rrs. However, when the animals were pretreated with atropine, ANP infusion significantly reduced the increase in Rrs induced by histamine (30 +/- 2 vs 51 +/- 6 cmH2O l-1 s; P < 0.05). 4. These data suggest that ANP has an indirect modulating effect on the airway smooth muscle and will decrease Rrs when muscarinic receptors are blocked.


Subject(s)
Atrial Natriuretic Factor/pharmacology , Receptors, Muscarinic/drug effects , Respiratory System/drug effects , Airway Resistance/drug effects , Animals , Atrial Natriuretic Factor/blood , Blood Gas Analysis , Blood Pressure/drug effects , Bronchoconstriction/drug effects , Histamine/pharmacology , Male , Muscle, Smooth/drug effects , Parasympatholytics/pharmacology , Rabbits , Respiratory Function Tests , Sympatholytics/pharmacology
18.
J Allergy Clin Immunol ; 87(4): 762-7, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2013669

ABSTRACT

The aim of this work was to establish whether beta-adrenergic agonists promote or increase gastroesophageal reflux in patients with asthma. Ten healthy individuals and eight patients with asthma were studied on 2 different days. One day they received a placebo, and the other day they received 4 mg of salbutamol by mouth. Complete measurements of esophageal manometry were performed before and every 30 minutes for 210 minutes after the administration of the drugs. Esophageal pH was measured continuously for the duration of the experiment. The results demonstrate that (1) salbutamol had no effect on the lower esophageal sphincter pressure gradient, the peak esophageal contraction pressure, or the number and duration of reflux episodes in patients with asthma and normal individuals, and (2) patients with asthma have a resting lower esophageal sphincter pressure higher than healthy subjects. We conclude that the administration of salbutamol does not affect esophageal function.


Subject(s)
Albuterol/pharmacology , Asthma/complications , Gastroesophageal Reflux/complications , Adolescent , Adult , Albuterol/blood , Asthma/physiopathology , Female , Gastroesophageal Reflux/physiopathology , Humans , Male
19.
Biochem Biophys Res Commun ; 160(2): 808-12, 1989 Apr 28.
Article in English | MEDLINE | ID: mdl-2541712

ABSTRACT

The aim of this study was to measure the effects of an increase in negative intrathoracic pressure on the release of ANF. With the subjects seated comfortably, 3 control blood samples were obtained over 30 minutes. Eight subjects then breathed for 30 min. through an inspiratory resistance in such a way that maximal inspiratory pleural pressures were between -30 to -40 cmH2O. Three blood samples were withdrawn after 20, 25, and 30 min., with the subject still breathing against the artificial resistance. Plasma concentrations of ANF were analysed by RIA. They measured: control value 24.6 +/- 3.7 pg ANF/mL (X +/- SE); with resistance 37.1 +/- 8.1 pg/mL (p less than or equal to .05). These results suggest that ANF could be released during an asthma attack.


Subject(s)
Airway Obstruction/physiopathology , Atrial Natriuretic Factor/blood , Adult , Airway Obstruction/blood , Airway Resistance , Atrial Natriuretic Factor/metabolism , Blood Pressure , Catecholamines/blood , Cyclic GMP/blood , Female , Humans , Male , Pulse , Renin/blood
20.
Am Rev Respir Dis ; 138(6): 1548-52, 1988 Dec.
Article in English | MEDLINE | ID: mdl-3202505

ABSTRACT

The aim of this work was to determine if the nonadrenergic noncholinergic nervous system can be reflexly activated in asthmatic patients by stimulating the vocal cords. The stimulation was produced by a cytology brush passed through a bronchoscope previously introduced transnasally and positioned just above the epiglottis. The subjects were premedicated with cholinergic blockers, and bronchoconstriction was induced by inhalation of histamine. In 11 experiments performed on six patients, vocal cords stimulation resulted in a decreased RL from 8.4 +/- 1.0 to 6.3 +/- 0.8 cm H2O.L-1.s (mean +/- SE) (p less than 0.01). To assess the possible contribution of circulating catecholamines to this decrease, plasma epinephrine and norepinephrine levels were measured in six experiments, before and 30 s, 1, 3, and 5 min after the stimulation. Pulmonary resistance fell from 10.0 +/- 1.3 to 7.6 +/- 0.9 cm H2O.L-1.s (mean +/- SE) (p less than 0.05) 30 s and to 7.9 +/- 0.9 cm H2O.L-1.s (p less than 0.05) 60 s after stimulation. Epinephrine and norepinephrine levels increased slightly but not significantly throughout the experiment. We conclude that in asthmatic patients, as in normal subjects, stimulation of the vocal cords produces a reflex decrease in histamine-induced bronchoconstriction which is modulated by the nonadrenergic noncholinergic nervous system.


Subject(s)
Asthma/physiopathology , Bronchi/physiopathology , Histamine/pharmacology , Larynx/physiopathology , Reflex/physiology , Administration, Inhalation , Adult , Asthma/blood , Autonomic Nervous System/physiopathology , Bronchi/drug effects , Bronchi/innervation , Epinephrine/blood , Female , Humans , Male , Middle Aged , Norepinephrine/blood , Physical Stimulation
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