PubMed Health⌕ Search

Biomedical subjects

F Lavaud

Publications and source records attributed to F Lavaud.

At least 37 records · Page 2Linked to original sources
PubMed1996

Differential spontaneous expression of mRNA for IL-4, IL-10, IL-13, IL-2 and interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells (PBMC) from atopic patients.

Distinct cytokine-producing T cell subsets are well known to play a major role in IgE production and to be differentially regulated in allergic patients, although the characterization of the type 1/type 2 cytokine pattern in PBMC during allergic responses remains to be clearly defined. The aim of this study was to determine whether different cytokine profiles are observed directly in PBMC of atopic donors. We attempted to study several cytokines (IL-2, IFN-gamma, IL-4, IL-10 and IL-13) using not only ELISA but also polymerase chain reaction (PCR) techniques, because the frequency of cytokine-producing cells in peripheral blood is very low. All the patients were selected during their acute symptomatologic phase. Data showed a significantly higher production of IL-4 (P = 0.05) and IL-10 (P < 0.005) as determined by ELISA in phytohaemagglutinin (PHA)/phorbol myristate acetate (PMA)-stimulated mononuclear cells of atopic donors compared with controls, although spontaneous IL-4 production without stimulation was never detected within either atopic or control groups. The reverse-transcriptase (RT)-PCR technique appeared to be advantageous in that it allowed the detection of the spontaneous expression of cytokine mRNA in cells without stimulation. We found a clear expression of IL-4 mRNA spontaneously in all atopic patients, whereas normal donors in most cases did not show specific signals (P < 0.0001). Less differences between atopic subjects and controls were found in IL-10 mRNA expression. Although the technique of RT-PCR amplification used in this study is semiquantitative, a reproducible and significant (P < 0.001) enhancement of IL-10 mRNA expression was observed in atopic donors. A heterogeneous expression of IL-13 mRNA was observed in individuals from the two groups studied, although mean levels in atopic donors were slightly enhanced compared with controls (P = 0.02). Furthermore, we did not observe any alteration in the expression of the type 1-derived cytokines such as IFN-gamma and IL-2. In addition, we showed a lack of correlation between the expression of serum IgE (total or specific) and spontaneous IL-4 mRNA expression. This study showed a tendency of PBMC from atopic donors to express a type 2-like cytokine pattern, with IL-4 as the most discriminatory cytokine. Additionally, as the level of serum IgE has a low predictive value in allergic disease, and as the elevated expression of IL-4 that we found was not correlated with serum IgE, we could strongly suggest that the measurement of IL-4 in blood mononuclear cells may be of great value in the analysis of allergic responses in atopic donors.

Adolescent↗
PubMed1996

Spontaneous CD30 mRNA expression in peripheral blood mononuclear cells from atopic patients with high IgE serum levels.

CD30 is a surface molecule which can be expressed by normal B and T lymphocytes. Our study focused on the CD30 expression and release compared with IL-4 expression as well as CD23-alpha/beta in peripheral blood mononuclear cells (PBMC) from atopic subjects and controls. Data showed a lack of CD30 mRNA expression in the PBMC of control subjects, while it was significantly expressed in those of 6/11 atopic patients. No substantial amounts of spontaneous soluble CD30 (sCD30) could be detected by ELISA in both atopic and control groups. Interestingly, CD30 mRNA expression in PBMC of allergic patients was positively correlated with IgE serum levels (r = 0.79, P = 0.003). Studies on purified B cells showed that CD30 was expressed mainly in CD19+B cells of allergic patients. These data suggest highly a potential functional significance of the CD30 molecule in IgE response during allergic diseases.

Adolescent↗
PubMed1996

Erythema multiforme due to pyrazinamide.

Drug-induced erythema multiforme is reported with many antimicrobial and antipyretic medications. We present one patient who experienced erythema multiforme and urticaria after administration of pyrazinamide for treatment of cutaneous tuberculosis. The side-effects of pyrazinamide include hepatic or dermatologic disorders, but erythema multiforme has not yet, to our knowledge, been described. Clinical features and discontinuation and reintroduction of the drug led us to consider pyrazinamide the cause of the erythema multiforme, but allergologic studies remained negative, except for the presence of circulating immune complexes. The mechanism of this eruption remains obscure, and definite withdrawal of pyrazinamide seems to be the best therapeutic choice.

Aged↗
PubMed1996

[Carcinoid thymus tumor at an advanced age: diagnostic value of mediastinal needle biopsy with computerized tomography].

Carcinoid tumour of the thymus is a rare neuroendocrine tumour particularly at an advanced age. The authors report a case of a mediastinal mass in a man aged 85, the mass had remained asymptomatic for a long time. It was decided to achieve a diagnosis because the tumour was causing local compression: a mediastinal needle biopsy under computerised tomographic control confirmed that this was a carcinoid tumour and a study of the biopsy material using an electron microscope showed neurosecretory granules. A sternotomy enabled the tumour to be excised but a post-operative Pseudomonas pneumonia led to the death of the patient. This case underlines the diagnostic place of mediastinal needle biopsy in the presence of a mediastinal tumour. The technique can be carried out under computerised tomography or ultrasonography and this can be associated with a study of the biopsy specimen using electron microscopy which enables the diagnosis to be made before any therapeutic decisions. The treatment of choice of a carcinoid tumour of the thymus is surgery which confirms the tumour limits and also its thymic origin. Tumour excision can be completed using radiotherapy or even chemotherapy.

Age Factors↗
PubMed1995

Allergy to latex, avocado pear, and banana: evidence for a 30 kd antigen in immunoblotting.

Allergens of natural latex, latex gloves, avocado pear, and banana extracts were investigated by an immunoblotting technique in sera of patients experiencing associated latex and fruit allergies. Extracts were separated by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis and electroblotted onto nitrocellulose. After incubation with patients' sera, IgE antibodies were revealed by a goat anti-human IgE alkaline-phosphatase conjugate. Seventeen serum samples from patients with well-documented latex allergy were studied. Among these patients, 10 demonstrated an allergy to avocado pear sometimes associated with banana. In sera from patients with latex and fruit allergy, prominent IgE binding was revealed at about 30 kd with latex and fruit extracts. Serum controls remained negative. Cross-inhibition of immunoblotting confirmed that this main allergen is linked to a common epitope present in latex and fruits. This must be related to clinical findings and previous observations of cross-reactivity.

Adult↗
PubMed1995

[Retrospective study of pneumoconiosis in Champagne-Ardenne].

This study was carried out in two departments of Champagne-Ardenne. The aim was to assess the level of retrieval in patient population suffering from pneumoconiosis who were hospitalised with this disorder, compared to another population who had contracted the same disease in the working environment and were known to the local social security benefit office in the North East (CRAMNE). A list of 77 names of hospitalised patients had been obtained following requests for mineralogical analysis addressed to a specialised national laboratory. A second list of 59 names of patients who were receiving compensation for pneumoconiosis was provided by CRAMNE. Five subjects were common to both populations. The discordance between the two was partly explained by the non-recognition of the system of compensation for indemnifiable occupational disease. The recruitment of hospitalised patients leads to a bias which influences the distribution of pneumoconiosis patients. Subjects presenting with the most consistent abnormalities in pulmonary function did not all figure amongst the notified cases.

Adult↗
PubMed1994

Baker's asthma related to soybean lecithin exposure.

We report two cases of soybean-lecithin-induced asthma in bakers. The patients experienced clinical symptoms in relation to an occupational exposure to this additive. Skin tests were positive with soybean lecithin, RAST showed a sensitization to soybean, and bronchial challenge tests were positive for a dilution of 10(-3) with this allergen. The same tests remained negative among healthy and asthmatic controls. Soybean lecithin, a common additive in bakery, must be added to the list of numerous aeroallergens involved in baker's asthma.

Adult↗
PubMed1994

[Importance of serum TPA determination in bronchopulmonary cancer. A comparative study of CEA, CA 19.9 and NSE].

This study concerns 45 patients group one suffering from broncho-pulmonary cancer, the diagnosis was obtained by bronchial biopsies or by transparietal puncture using a scanner: there were 35 non-small cell bronchial carcinomas (CNPC) and 10 small cell bronchial cancers (CPC). The control patients (99 patients) were divided up as follows: 44 pleuro-pulmonary infections (group two) and 55 with respiratory failure of various causes other than infectious episodes (group three). In group one the level for TPA was positive in 30 cases (the threshold value was 90 units per litre), 9 for CA 19.9, 7 for ACE and 9 for NSE. The overall sensitivity was thus better for TPA. There was no correlation between TPA and type of tumour histology nor between the different markers. Their association did not improve the sensitivity. The NSE however, remained the most sensitive test for the diagnosis of CPC with six positive tests out of ten. In the control population, the specificity of TPA (66%) was less than that of ACE (100%) or of CA 19.9 (94%) and the false positives were significantly more numerous in group two: 21 patients had a positive test compared to only 12 in group three. Finally we noticed an increase in the level of TPA contrary to other markers, as a function of the extent of the disease from the carcinoma (CNPC unique). The TPA is thus the most sensitive and it turns out to be better reflector to the extent of the tumour disease than either ACE, CA 19.9 or NSE but this applies uniquely to non-small cell carcinoma.

Adenocarcinoma↗
PubMed1994

[Bronchial epidermoid carcinoma with unusual disclosure].

Dissemination has often occurred before the diagnosis of bronchopulmonary cancer. Pancreatic metastases are exceptional and are very rarely the revealing manifestation. The authors report a case of a tumour of the pancreas which led to the discover of an bronchogenic epidermoid carcinoma. The relationship between these two tumours lead to the proposed hypothesis of pancreatic metastasis of a bronchogenic carcinoma. Although this situation is rare, the preoperative work-up for bronchogenic carcinoma should include computed tomography of the pancreas if the abdominal echography does not allow complete visualization of the pancreas in cases with suggestive digestive disorders. If a tumour is observed in the pancreas, scan-guided needle biopsy should be performed to enable the histological examination.

Carcinoma, Bronchogenic↗
PubMed1993

[Bronchial biopsy, curative treatment for cancer in situ?].

Bronchial carcinoma in situ is an intra-epithelial proliferation of tumour which does not cross the basement membrane and is asymptomatic. The evidence for this cancer often rests on a biopsy carried out on a bronchus which may show simple inflammation or may even be normal. We report a new observation on a bronchial carcinoma in situ which was completely ablated after a bronchial biopsy. However surgery remains the first form of treatment for bronchial cancer. If the patient is inoperable, endobroncho-cryotherapy, radiotherapy or phototherapy may be tried but tumour recurrence remains a possibility.

Aged↗
PubMed1992

[Detergent enzymes: has the risk of occupational sensitization disappeared?].

Occupational allergy to enzyme detergents had almost disappeared by the use of preventive measures, both individually and in industries. The occurrence of 8 new cases of asthma in a detergent factory has led to a prospective clinical and aetiological enquiry. Although there was no documentation using the specific provocation test or by measuring respiratory function whilst at work, the occupational character of this asthma seemed possible after taking a history. Sensitization to the enzymes used (Savinase, Maxatase and Biozym P 300 S) was shown by skin tests (8 positive to all the enzymes) and the level of specific IgE to Rast (8 times greater than class 3 for Savinase and Maxitase) and for HBDT for Maxatase and Biozym P 300 S (greater than 50% in 8 patients). From another stand point the incomplete application of preventive measures within the factory did not seem to totally explain the origin of this sensitization. In fact, it was the study of the morphology of the enzyme grains, which had been introduced into the factory which helped us to explain the mechanism. In effect it was the capsules of the grain which were fissured and thus allowed allergen contact. The replacement of these grains whose envelope was intact, led to the disappearance of the symptoms and confirmed our hypothesis. There remains a continuing risk from occupational sensitization to asthma and it is suggested that there is continued collaboration between the medical profession and industry.

Adult↗