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Abstract: This paper describes the development of a chemical sensor based on a YSZ (8mol.% Yttrium doped Zirconia) thimble tube associated with three metallic electrodes: one internal in platinum in contact with ambient acts as a reference and two externals ones, one in platinum and the other in gold respectively measure oxygen and hydrocarbon concentrations. This device is dedicated to combustion control in industrial processes. Optimization of this sensor concerning electrodes geometry''s and temperatures in regards of responses to oxygen and carbon monoxide in laboratory conditions is presented. [Copyright &y& Elsevier]

Study Objectives: Cystic fibrosis (CF) is one of the most common inherited diseases among whites. Since the cloning of the CF transmembrane conductance regulator (CFTR) gene, a number of studies have focused on associations between the genotype and phenotype in CF. This had led to the progressive identification of new groups of patients, including those who have mild lung disease and those who have normal sweat chloride values (< 60 mEq/L). The aim of the present work was to provide information on the genotype and the phenotypic characteristics of children with intermediate-range sweat chloride test results.Patients and Results: We focused on children referred to the pulmonary department for various types of pulmonary disease and who had several sweat chloride test results with median values in the range of 40 to 60 mEq/L. Twenty-four patients over a 10-year period were enrolled (mean age, 4.8 years). Respiratory manifestations at initial evaluation included recurrent bronchitis, wheezing, chronic cough, and pneumonia. The duration of the follow-up ranged from 0.5 to 10.5 years. Sputum cultures revealed the presence of Haemophilus influenzae (10 children), Staphylococcus aureus (4 children), and Pseudomonas aeruginosa (3 children). Pancreatic insufficiency was found in two patients. Analysis of the entire coding sequence allowed identification of 16 known mutations in CFTR gene. Fifteen chromosomes (31.2%) carried a mutation in CFTR gene and one allele carried two mutations. Three patients were homozygous or double heterozygous (DeltaF508/DeltaF508, DeltaF508/3849 + 10 kb C-->T, S1235R/G551D). The 5-thymidine allele was identified in four children.Conclusion: These results indicate an higher frequency of CFTR gene mutations in patients with borderline sweat chloride test results, compared to data reported in the general population. They lead to the recommendations for complete pulmonary and GI investigations in this group of patients, as well as assiduous care and medical follow-up. [ABSTRACT FROM AUTHOR]

A method is described which allows the tridimensional determination of the occlusal position. The device comprises an intra-buccal transducer and a remote recorder where the signals received by microwaves are decoded, translated and recorded. The transducer is miniaturized and small enough to be placed within the wax rims of the bite plate of an endetulous patient. As the bite plate is comparable in size to the patient's future denture and the latter is not inconvenienced by wire coming out of his mouth, the experiment takes place in what are normal physiological conditions. The results achieved so far through preliminary clinical experience are encouraging. Further work is in progress. [ABSTRACT FROM AUTHOR]

Burkholderia cepacia, Stenotrophomonas maltophilia, and Alcaligenes xylosoxidans have been isolated with increasing frequency from the sputum of patients with cystic fibrosis in a pediatric hospital. In 1994-95, 27 of 120 patients were persistently colonized, 17 with Burkholderia cepacia, eight with Alcaligenes xylosoxidans, and five with Stenotrophomonas maltophilia. Genotyping of 220 clinical isolates revealed that most of the Burkholderia cepacia strains were clonally related, suggesting either cross-infection or a common source of exposure. In contrast, neither crossinfection nor a common source of exposure appear to have occurred in the cases of Alcaligenes xylosoxidans or Stenotrophomonas maltophilia. [ABSTRACT FROM AUTHOR]

A case of retroperitoneal pulmonary fistula caused by a neonatal adrenal abscess is reported. The adrenal abscess was diagnosed by means of needle aspiration which guided the choice of antibiotic therapy. The fistula was demonstrated by direct injection of contrast medium into the adrenal abscess. Treatment by needle aspiration of the adrenal abscess and intravenous antibiotics was successful. [ABSTRACT FROM AUTHOR]

Abstract: Recently, oxide semiconductor material used as transducer has been the central topic of many studies for gas sensor. In this paper we investigated the characteristic of a thick film of tin dioxide (SnO2) film for chemical vapor sensor. It has been prepared by screen-printing technology and deposited on alumina substrate provided with two gold electrodes. The morphology, the molecular composition and the electrical properties of this material have been characterized respectively by Atomic Force Spectroscopy (AFM), Fourier Transformed Infrared Spectroscopy (FTIR) and Impedance Spectroscopy (IS). The electrical properties showed a resistive behaviour of this material less than 300 °C which is the operating temperature of the sensor. The developed sensor can identify the nature of the detected gas, oxidizing or reducing. [Copyright &y& Elsevier]

Progression of pulmonary sarcoidosis in children remains poorly documented. The aim of this work was to gather follow-up information on pulmonary outcomes in children with sarcoidosis and to obtain data of relevance to a discussion of the optimal length and regimen of glucocorticoid therapy. In the present study, the authors experience of pulmonary sarcoidosis in 21 children referred to the paediatric pulmonary department over a 10-yr period is reported with a documented follow-up of at least 4 yr. Evaluation of the disease during the follow-up included analysis of clinical manifestations, chest radiographs, pulmonary function tests with measurements of the vital capacity (VC), dynamic lung compliance (CL,dyn), lung transfer for CO (TL,CO), and arterial blood gases, as well as bronchoalveolar lavage (BAL) with determination of total and differential cell counts. After initial evaluation the decision was a careful observation of four children without therapy. Corticosteroid treatment was initiated in 17 children. Analysis of results indicated that after 6-12 months of treatment most clinical manifestations of the disease and chest radiograph abnormalities disappeared, and beneficial effects on VC and TL,CO were apparent. After 18 months of steroids no benefit on pulmonary function tests could be noticed, with mainly persistence of alterations of CL,dyn. Results of BAL studies documented the presence of an alveolitis with increased lymphocyte populations throughout the follow-up. Relapses were observed in four children during tapering of prednisone; they were not reported after discontinuation of steroid therapy. Taken together data obtained in the presented population can lead to the following suggestions for the management of pulmonary sarcoidosis in children. BAL should be performed at the initial evaluation to document alveolitis; however, nothing seems to be gained from repeating this investigation during follow-up in the absence of specific reasons. Once the decision to initiate glucocorticoid therapy is made, 18 months may be a reasonable treatment duration. Discontinuation of therapy can be decided even if the pulmonary function tests remain abnormal, but the child should then be carefully monitored for a relapse.

The dominant role of inflammation in airways disease progression in cystic fibrosis (CF) is now well established and, based on recent findings, the possibility of an inappropriate inflammatory response in the lung of patients with CF has emerged. In order to characterize this response, the aim of the present work was to evaluate the levels of a number of pro- and anti-inflammatory cytokines in the sputum of CF children and to compare these levels to those observed in the sputum from non-CF children with diffuse bronchiectasis (DB). Three groups of patients were investigated: a group of 25 CF children (mean age: 12.2 yrs), a group of 10 non-CF children with DB (mean age 11.5 yrs), and a group of five healthy young adults (mean age 24 yrs). Elevated concentrations of pro-inflammatory cytokines, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-8 were found in children with CF and in non-CF children with DB, with significantly higher concentrations of IL-1beta in CF children. Analysis of the natural anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) and type II TNF soluble receptor (sTNFRII) concentrations showed distinct patterns, with elevated levels of both inhibitors in CF patients, whereas only sTNFRII was found to be increased in non-CF children with DB. IL-10 data indicated low concentrations in the CF group. In all CF children, the concentrations of IL-6 in the airways were extremely low, independent of the clinical, bacteriological or functional status. By contrast, significantly increased IL-6 levels were found in non-CF children with DB. These results document distinct cytokine profiles in cystic fibrosis patients and noncystic fibrosis patients. They also suggest that impairment of interleukin-6 expression may represent an important component of the excessive inflammatory response observed in cystic fibrosis.

The prognosis for children with chronic interstitial lung disease is poor and the mortality rate is high, especially in infants. This explains the many therapeutical protocols which have been proposed and investigated by several authors. In the present work, we evaluated the response of three infants with idiopathic pulmonary fibrosis to high-dose intravenous prednisolone pulses. The patients were referred to the department at the age of 4, 17, and 3 months, respectively. The diagnosis was confirmed by open lung biopsy and intravenous pulse methyl prednisolone therapy was started with the following protocol: 300 mg/m2 methylprednisolone daily for 3 days, repeated every 4 to 6 weeks. Because of the extreme severity of the respiratory distress at the time of diagnosis, the intravenous pulse treatments were initially complemented by oral prednisone. Clinical improvement was noticed within 6 months with progressive correction of hypoxemia. After follow-up for 3.5 to 4 years, with a total number of pulses of 37, 26, and 32, respectively, the children are symptom-free and do not require oxygen supplementation. During this period, no side effects and no adrenal insufficiency could be documented. Based on current knowledge of steroid action, it can be speculated that the response to intermittent high-dose intravenous methylprednisolone may explain the ability of this mode of hormone administration to maintain an adequate level of glucocorticoid receptor expression. More information and trials through multicenter collaborations are needed to assess therapeutical protocols of repeated high-dose intravenous steroid treatment.

Cystic fibrosis is characterized by the accumulation of thick viscous purulent secretions. Recombinant human deoxyribonuclease I (rhDNase) breaks down extracellular DNA, which contributes to the increased viscosity of sputum. A multinational, open-label study was conducted in 974 cystic fibrosis patients with moderate lung disease [forced vital capacity (FVC) 40-70% of predicted values] to examine the safety and efficacy of aerosolized rhDNase, 2.5 mg, once daily over a period of at least 12 weeks. Patients were assessed under conditions reflecting routine clinical practice. During rhDNase therapy, at least one respiratory tract infection (RTI) requiring intravenous antibiotics was experienced by 29.5% of patients. Forced expiratory volume in 1 second (FEV1) and FVC were significantly improved from baseline by a mean of 10.5% and 7.2%, respectively. Voice alteration and pharyngitis were the most frequent rhDNase-related adverse events, but only 2% of all patients discontinued treatment due to adverse events. The results obtained were similar to a subanalysis of data from the first 3 months of a placebo-controlled U.S. study. The patients in the present study had a similar frequency of RTIs and improvement in pulmonary function, and reported fewer rhDNase-related and cystic fibrosis-related adverse events than patients in the U.S. study. We conclude that administration of rhDNase is safe, well tolerated, and effective under conditions reflecting routine clinical practice in patients with cystic fibrosis and moderate lung disease.

The involvement of the insulin-like growth factor (IGF) system in lung growth and repair following injury is sustained by a number of studies. Based on this knowledge, the aim of the present work was to document the expression of the IGFs and their binding proteins by alveolar cells obtained by bronchoalveolar lavage (BAL). Two groups were investigated: a control group of five children and a group of 11 children referred to the department for exploration of interstitial lung disease (ILD). Components of the IGF system studied included IGF-I, IGF-II and IGF-binding proteins (IGFBP). Expression of these factors was analysed at the level of messenger ribonucleic acid (mRNA) (by semi-quantitative reverse transcription polymerase chain reaction techniques), and of protein for the IGFBPs. In addition, expression of two major cytokines associated with the inflammatory process, tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta), was also documented. In children without parenchymal disease, the growth factor expressed was IGF-I, in association with the presence of mRNA for IGFBP-2 in all cases. In children with ILD, expression of IGF-I was observed in nine patients and of IGF-II in three patients, and the presence of IGFBP-2 was found in all extracts analysed (mRNA and proteins). Evaluation of IGFBP-2 expression indicated an increase in the group of children with ILD. Interestingly, a significant association was observed between the increase in IGFBP-2 expression and TGF-beta expression. The present data emphasize the presence on insulin-like growth factor-binding protein-2 in the BAL of all patients, and suggest that this protein may be an important factor of the injury/repair processes during the progression of alveolar inflammation.

Background: Patients with cystic fibrosis (CF) may be predisposed to airway infections with unusual organisms, such as mycobacteria. The aim of the study was to determine the incidence and clinical picture of mycobacterial infection in CF children., Methods: At least 2 acid-fast bacillus (AFB) smears and mycobacterial cultures were performed on a prospective basis on 682 sputum specimens from 106 patients during a 1-year period., Results: Thirty-three percent of the cultures were contaminated with other bacteria. Seven children had at least one sputum culture positive for one mycobacterium. Five children had only one positive AFB culture. Their clinical status and lung function remained stable during follow-up. Two teenagers with severe lung disease had several positive AFB smears and cultures for Mycobacterium chelonae and Mycobacterium abscessus. The isolation of M. chelonae and M. abscessus was associated with a clinical and functional decline. Clarithromycin treatment resulted in temporary improvement with the disappearance of the mycobacteria after 6 months of treatment. This prospective study shows an incidence of 2.3% for positive cultures. The prevalence was 6.6% for mycobacterial colonization but only 1.9% for mycobacterial lung disease in our pediatric population., Conclusions: We recommend performing AFB smears and cultures in CF children with severe lung disease and/or during a lung exacerbation. In these patients persistence of M. chelonae or M. abscessus in sputum should lead to consideration of treatment with clarithromycin.

More than 600 mutations have been identified in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene and are known to cause cystic fibrosis (CF). This large number of mutations makes the search of the molecular defects in CF patients difficult. We have used the techniques of denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing to detect the mutations in 334 CF chromosomes mostly of French origin. The whole coding sequence of the CFTR gene corresponding to the 27 exons and their exon-intron boundaries was studied. 45 different mutations were identified. This method allowed us to detect the molecular defect in 90.5% of the mutant alleles and to report a novel mutation D979V.

Idiopathic pulmonary fibrosis is a poorly characterized disease in infants. In the present report, we reviewed our experience with 10 infants during a 10-year period. In 9 patients, onset of symptoms occurred before the age of 2 months and included tachypnea, cough, and inadequate weight gain. However, despite the presence of these symptoms, diagnosis was delayed for 3 months at which time the infants were referred to the pediatric pulmonary department, when the diagnosis was confirmed by open lung biopsy. At the time of admission, bronchoscopy with alveolar lavage was performed in 9 children and showed severe alveolitis with an increase in the neutrophil count. Nine infants were treated with prednisone alone or in combination with chloroquine, colchicine, or cyclophosphamide; all these patients died despite treatment. One infant was treated with pulses of methylprednisolone because of a failure in response to oral prednisone. This girl who displayed similar clinical, radiological, and histological abnormalities as the other children at the time of diagnosis is the only child still alive after 3 years of follow-up. She is now free of respiratory symptoms and has a normal growth curve. The present report raised two important points: (1) a thorough evaluation of characteristic symptoms should lead to an early diagnosis of pulmonary fibrosis in infants; and (2) administration of pulse therapy using corticosteroids has been helpful and needs to be evaluated further.

Since 1987, Pseudomonas cepacia has been isolated with an increasing frequency in the expectorants of children with cystic fibrosis followed at the Hôpital d'enfants Armand Trousseau (Paris, France). Colonization by P. cepacia may be responsible for serious secondary infections and rapid deterioration in respiratory function in these patients. Among the 130 children attending our centre, 14 (8 girls and 6 boys) aged 3 to 18, exhibited chronic colonization. 132 isolates, originating from sputum obtained between 1992 and 1994 were studied. Nine biochemical patterns and 6 antibiotic susceptibility patterns at least were defined, therefore exhibiting great polymorphism. Chromosome restriction patterns with Xba I after pulsed field gel electrophoresis enabled 4 pulsotypes to be identified: A, B, C and D. Thirteen patients harboured pulsotypes A, C and D, and 1 patient pulsotype B, the last being quite distinct from the first three. Pulsotypes A, C and D were almost similar, suggesting that closely related strains, probably the same strain, was harboured by 13 of the 14 patients. The origin could be contamination from a single source, or stem from patient-to-patient crossed transmission.

The increased survival rate of malignant diseases due to more aggressive treatments contributes to the occurrence of drug-induced pulmonary diseases (DIPD). We reviewed, retrospectively over a 10-year period, 15 children (8 girls) who presented a DIPD. Their mean age was 9 years (range, 1 to 17 years), with an underlying malignant disease in 14 (9 leukemias). Three typical patterns have emerged from this analysis: (1) acute hypersensitivity lung disease caused by methotrexate (in 6 patients) or azathioprine (in 1 patient). This acute syndrome consisted of alveolar-interstitial infiltrate with a hypercellularity on bronchoalveolar lavage (BAL) (mean, 714,286 cells/mL; range, 180,000-2,940,000 cells/mL) and an increase of lymphocyte counts (mean, 39%; range 11-64%) with predominantly CD8-suppressor/cytotoxic lymphocytes. Inhibition of leukocyte migration or leukocyte aggregation in the presence of low drug concentrations was positive in the 5 cases tested. Lung function tests showed a restrictive pattern and the outcome of DIPD was always favorable. (2) Chronic pneumonitis/fibrosis was seen in 6 patients who received a variable association of cyclophosphamide (3 patients), bleomycin (2 patients), BCNU (2 patients), and melphalan (1 patient). Symptoms of an alveolar-interstitial pneumonitis developed progressively. BAL showed a moderate increase of total cell numbers (mean, 495,000 cells/mL; range, 150,000-900,000 cells/mL). Lung function tests showed a restrictive pattern. Despite corticosteroid treatment in 4 children, one died after bleomycin lung injury and 2 had functional lung impairment. (3) Noncardiogenic pulmonary edema occurred in 2 patients with leukemia treated with recombinant interleukin II. BAL showed hypercellularity and outcome was rapidly favorable.(ABSTRACT TRUNCATED AT 250 WORDS)

Sarcoidosis is a multisystemic granulomatosis of unknown etiology which mainly affects young adults. It is characterized primarily by bilateral hilar adenopathies, a pulmonary infiltrate and cutaneous and ocular lesions. It rarely occurs in children under the age of 16. Localization in the upper respiratory tract (URT) is infrequent and sarcoidosis of the URT in children is exceptional, with only 13 cases reported in the literature. In the present report we describe the clinical, diagnostic explorations, histological and therapeutic aspects of 2 new cases in children.

The clinical course of sarcoidosis in children has not been well defined. Eight children with symptomatic sarcoidosis included in this study underwent pulmonary function tests and bronchoscopy with bronchoalveolar lavage (BAL) before treatment and during steroid therapy. At the start of therapy, functional parameters, mostly dynamic lung compliance and lung transfer factor for CO, were impaired. This was associated with abnormalities of BAL cell populations: increased total cell number with a high proportion of lymphocytes, modifications of lymphocyte subpopulation with an elevated CD4+/CD8+ ratio, and enhanced ability of alveolar macrophages to release hydrogen peroxide. Although respiratory abnormalities seemed to be similar at the initial stage of sarcoidosis in children and adults, the course of the disease appeared to be different. Despite the absence of respiratory symptoms and disappearance of chest radiographic abnormalities on prolonged steroid treatment, we found slow improvement of pulmonary functions associated with persistence of BAL lymphocytosis and elevated CD4+/CD8+ ratios. However, the ability of alveolar macrophages to release hydrogen peroxide was significantly reduced after 6 months of steroid treatment, and it remained identical to the control group. Therefore, the evaluation of disease activity appears to be critical for therapy in pediatrics, and for this purpose studies of alveolar macrophage activation may be of particular interest.