Publications by authors named "Bertholon J"

Article Synopsis
  • - The study aimed to compare the effects of different diluent volumes (6 mL vs. 12 mL) on aerosol characteristics and pharmacokinetics of nebulized colistimethate sodium (CMS) for treating ventilator-associated pneumonia caused by multidrug-resistant (MDR) bacteria.
  • - Results showed that the 6 mL diluent led to smaller aerosol particle sizes and shorter nebulization times, while pharmacokinetic measures in plasma and urine remained similar across both diluent volumes.
  • - The study concluded that using 6 mL for CMS dilution improves nebulization efficiency and stability without negatively affecting drug delivery or absorption in the body.
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In previous studies of the smoke from regular cigarettes and water pipes, we measured aerosol particle sizes in three streams; S1, inhaled by the smoker, S2, released by the device itself and S3, exhaled by the smoker. We used an electrostatic low-pressure impactor (ELPI), giving particle size distributions in real time and calculated median diameters, D50, and dispersion (σg). This allowed us to predict airway deposition.

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Marketed since 2004 as an alternative to nicotine delivery and advertised as a valid means to smoking cessation, the electronic (e)-cigarette has been the subject of much controversy but very little experimental study. This review provides a brief summary of the current knowledge of this product. Propylene glycol and glycerol, the main ingredients of the fluid that is vaporized, have proved to be harmless in the fog machines of the entertainment industry.

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Background: A simple method for effective bronchodilator aerosol delivery while administering continuing continuous positive airway pressure (CPAP) would be useful in patients with severe bronchial obstruction.

Objective: To assess the effectiveness of bronchodilator aerosol delivery during CPAP generated by the Boussignac CPAP system and its optimal humidification system.

Methods: First we assessed the relationship between flow and pressure generated in the mask with the Boussignac CPAP system.

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Introduction: Second hand cigarette smoke consists predominantly of nanoparticles (with two dimensions less than 100 nanometres). The aim of this study was to examine the aerosol of cigarette smoke suspended in the air of a smoking room, its disappearance over the course of time, and its retention in the airways of passive smokers, as these processes remain poorly characterised.

Methods: A smoking machine produced cigarette smoke in a room.

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Introduction: It is a popular perception that narghile (water pipe) smoking is less harmful to the lungs than cigarettes in both active and passive smokers.

Methods: Using a sinusoidal pump we simulated water pipe smoking in conditions close to users' habits. The particle sizes and concentrations in the smoke streams were measured with an electrical low pressure impactor (ELPI), sorting particle numbers and size into 12 classes ranging from 0.

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Despite its increasing clinical use, almost no data are currently available about paclitaxel effects on non-cancerous mammary epithelial cells. We have previously established paclitaxel-resistant sub-cell lines (paclitaxel-surviving populations, PSPs; n=20), and sensitive controls (control clones, CCs; n=10), from the untransformed human mammary epithelial cell line HME1. In this study, we aimed to establish whether paclitaxel resistance was associated with a modified sensitivity to paclitaxel-induced aneuploidy.

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Introduction: For several decades a more peripheral distribution of the broncho-pulmonary pathologies related to tobacco has been observed.

Methods: The aim of this study is to examine whether changes in the particle size of cigarette smoke as the result of new manufacturing technologies could play a part in the observed epidemiologic changes through a more distal disposition of smoke particles in the airways. Using a smoking machine and a low pressure electrostatic impactor we measured the particle size of the smoke from six different types of cigarette, representing old and new manufacturing techniques.

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We investigated the potential in vivo aneugenic effects associated with paclitaxel treatment. For this purpose, we treated female nude mice with paclitaxel using doses equivalent to those used in weekly schedules at the clinical level (three cycles of 30 mg/kg/week for three consecutive weeks followed by one resting week). We then evaluated the frequencies of micronucleated erythrocytes (MNE) in peripheral blood using the acridine orange micronucleus assay.

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Cancers arise from the sequential acquisition of genetic alterations in specific genes. The high number of mutations in cancer cells led to the hypothesis that an early step in tumor progression is the generation of a genetic instability. The potent role of genetic instability in initiation and progression of colorectal cancers has been well defined in hereditary nonpolyposis colon cancer (HNPCC) syndrome.

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We investigated the mechanisms responsible for paclitaxel resistance in HME-1 cells (human mammary epithelial cells immortalized with hTERT). These cells were exposed to paclitaxel (10 pM for 7 days) and 20 cellular surviving populations (PSP) were obtained. PSP demonstrated high levels of resistance to paclitaxel cytotoxicity as compared with HME-1 cells.

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Numerous observations suggest that chromosome instability is caused by mitotic abnormalities such as errors in the partitioning of chromosomes. Chfr was recently defined as a central component of a new mitotic checkpoint that delays chromosome condensation in response to mitotic stress. Chfr was shown to be frequently inactivated in several human neoplasms, including colon, lung and esophageal cancers.

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Nebulization of solutions associating gomenol, dexamethasone and framycetin is very widespread in otorhinolaryngology (particularly for the treatment of actue laryngitis and post-traumatic laryngitis and rhinitis and for the tracheotomy care). A rigorous clinical evaluation is however lacking. The aim of this work was to evaluate use of such solutions in comparison with the recommendations issuing from the National Session in April 1997 on good practices for aerosol therapeutics.

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Transforming growth factor (TGF)-beta is known as an antiproliferative factor in the majority of mammalian cells, including stem germ cells. Lack of TGF-beta-induced growth inhibition has been associated with disruptions of TGF-beta receptors and SMADs. In the present study, we performed a mutational analysis of the TGF-beta signaling system, including TGF-beta receptor type I and type II and SMADs (SMAD1-SMAD7), in 20 seminoma germ cell tumors.

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Structural alterations to proto-oncogene sequences may be involved in the pathogenesis of human thyroid neoplasms. We studied 128 thyroid tumours (35 benign and 93 malignant) for ras gene point mutations in three different codons (12, 13 and 61) using a restriction fragment length polymorphism technique and direct sequencing of double-stranded DNA on polymerase chain-reaction-amplified tumour DNA. We found a high frequency of ras mutation for the Ha-ras codon 12 in follicular adenomas (7 of 35), particularly in atypical adenomas (5 of 17), in follicular carcinomas (6 of 19), with a high percentage for Hurthle cell carcinomas (6 of 11), and in papillary carcinomas (4 of 66).

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Objective: Various types of filters have been designed to prevent cross contamination of ventilation and respiratory devices. The aim of this study was to experimentally measure the retention efficiency of four simple filters (antibacterial and antiviral and seven combined filters (antibacterial and antiviral plus heat and water exchangers).

Setting: The respiratory function testing (EFR) central department of a university teaching hospital.

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We measured with a laser velocimeter granulometric deposit of an aerosol anti-infectious agent, fusafungin, administered with a controlled inhalator. Total drug deposit was determined on the basis of a granulometric spectrum of the polydispered aerosol (mass mean aerodynamic diameter (MMAD) = 2.8 +/- 1.

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The results of several studies, mostly without controls, have suggested that betablockers, administered at progressively increasing doses, may be beneficial in cardiac failure. Based on this hypothesis, betablockers with a peripheral vasodilator effect, such as Nebivolol, could be particularly valuable in this indication. A preliminary study of its tolerance, haemodynamic and neurohormonal effects was carried out with a noninvasive methodology in 12 patients with cardiac failure in sinus rhythm, 8 men and 4 women (average age 53 +/- 12 years), all of whom had Class III or IV symptoms according to the NYHA Classification.

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1. The dynamics of the ventilatory response to isocapnic hypoxia were studied in seven healthy subjects using four different levels of hypoxia, (inspired oxygen pressures, PI,O2 equal to 110, 100, 80 and 60 mmHg) successively increasing and decreasing stepwise. 2.

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1. The dynamics of the ventilatory response to carbon dioxide inhalation were studied in ten healthy young men using four different inspired fractions of carbon dioxide (FI, CO2) in air (0.015, 0.

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We have tested the hypothesis that there is a positive relation between arterial elasticity and physical working capacity (PWC) at a given age. The subjects were 28 young men, 16-18 yr old. Arterial elasticity was evaluated by measuring the carotid to femoral pulse-wave velocity (c) at rest.

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Chemical workers have become increasingly concerned about the presence of carcinogens in their occupational environment. As a result, a number of studies of excess cancer mortality have been undertaken in groups of workers with well-characterized exposures. This paper reports the results of one such study carried out in a polyamide-polyester factory in France.

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We carried out a maximum expiratory flow-volume curve (MEFV) and a spirometric recording with 67 athletes of different ages (15-27 years) and disciplines (rowers, kayakists, cyclists, swimmers) and with 20 adult and 13 adolescent nonathletic controls of matching ages. These recordings were repeated, with athletes only, after 6-10 months of training. Significant differences between the groups of adult athletes and the controls were observed for some parameters, the most discriminating of which were, in order, the peak expiratory flow (PEF), the forced expiratory volume in the first second (FEV1), and the flow at 75% of the vital capacity (V75).

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