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D Israel-Biet

Publications and source records attributed to D Israel-Biet.

At least 19 recordsLinked to original sources
PubMed2006

Effect of glucocorticoids on stem cell factor expression in human asthmatic bronchi.

BACKGROUND: Stem cell factor (SCF) is a major mast cell growth factor promoting differentiation, chemotaxis as well as inhibition of apoptosis of mast cells. Regulation of SCF expression by glucocorticoids has not yet been reported in human asthmatic bronchi. OBJECTIVE: To evaluate SCF mRNA and protein expression in biopsy specimen and bronchoalveolar lavage fluid, respectively, and to determine the mast cell numbers in biopsy sections from control and asthmatic subjects treated or not with glucocorticoids. METHODS: Volunteers were recruited out of pollen season. Asthmatic patients were allergic to common allergen extracts including grass and tree pollen, cat, dog or mite; three volunteers had non-allergic asthma. Mast cell numbers were counted after anti-human tryptase immunolabelling. SCF mRNA was quantified by real-time fluorescent PCR (LightCycler) after reverse transcription, and SCF protein was measured by ELISA. RESULTS: Asthmatic patients not treated with glucocorticoids showed a 5.8-, 1.8- and 3.1-fold significant increase in SCF mRNA, protein levels and mast cell numbers, respectively, compared with healthy volunteers of the control group (7.8 and 1.3 pg/mug SCF mRNA/GAPDH; 99.8+/-11.5 and 56.0+/-11.0 pg/mL SCF protein; 103+/-21 and 33+/-8 mast cells/mm(2), respectively; P<0.05). In asthmatic patients treated with glucocorticoids, a significant decrease of SCF mRNA, protein levels and mast cell numbers was observed as compared with untreated asthmatic patients (1.1 pg/microg mRNA; 62.0+/-10.3 pg/mL SCF protein and 39+/-13 mast cells/mm(2); P<0.05), reaching levels comparable to those of the control group. CONCLUSION: Our study shows that SCF is expressed in the bronchus in humans in vivo. This expression is increased in asthma, and is parallel to the increased mast cell numbers in the airways. Both increases were normalized in glucocorticoid-treated patients, strongly suggesting an involvement of SCF in the mast cell-associated asthmatic disease.

Adult↗
PubMed2005

Combined pulmonary fibrosis and emphysema: a distinct underrecognised entity.

The syndrome resulting from combined pulmonary fibrosis and emphysema has not been comprehensively described. The current authors conducted a retrospective study of 61 patients with both emphysema of the upper zones and diffuse parenchymal lung disease with fibrosis of the lower zones of the lungs on chest computed tomography. Patients (all smokers) included 60 males and one female, with a mean age of 65 yrs. Dyspnoea on exertion was present in all patients. Basal crackles were found in 87% and finger clubbing in 43%. Pulmonary function tests were as follows (mean+/-sd): total lung capacity 88%+/-17, forced vital capacity (FVC) 88%+/-18, forced expiratory volume in one second (FEV1) 80%+/-21 (% predicted), FEV1/FVC 69%+/-13, carbon monoxide diffusion capacity of the lung 37%+/-16 (% predicted), carbon monoxide transfer coefficient 46%+/-19. Pulmonary hypertension was present in 47% of patients at diagnosis, and 55% during follow-up. Patients were followed for a mean of 2.1+/-2.8 yrs from diagnosis. Survival was 87.5% at 2 yrs and 54.6% at 5 yrs, with a median of 6.1 yrs. The presence of pulmonary hypertension at diagnosis was a critical determinant of prognosis. The authors hereby individualise the computer tomography-defined syndrome of combined pulmonary fibrosis and emphysema characterised by subnormal spirometry, severe impairment of gas exchange, high prevalence of pulmonary hypertension, and poor survival.

Adult↗
PubMed2004

[Late presentation of a traumatic pulmonary arteriovenous malformation].

INTRODUCTION: Pulmonary arteriovenous malformations (PAVM) are rare, and most often of congenital origin. Among secondary causes of PAVM, trauma is exceptional. CASE REPORT: We describe here one such case, discovered very late over twenty years after a thoracic perforing wound. Recent vascular imaging techniques (angio-CT scanning and -RMI) have largely contributed to their diagnosis, but direct pulmonary arteriography remains the reference technique preoperatively when surgery is required. In all cases, treatment is as conservative as possible, and embolization of small sized PAVM, even multiple, by coils has become the standard procedure. However, surgery is required when the PAVM is large and/or proximal, particularly when its feeding vessel is complex. Itwas the case of our patient, who has been cured by a lobectomy. CONCLUSIONS: PAVM are rare but should be sytematically searche for in case of hypoxemia along with a pulmonary nodule.

Arteriovenous Fistula↗
PubMed2001

Local increase in the number of mast cells and expression of nerve growth factor in the bronchus of asthmatic patients after repeated inhalation of allergen at low-dose.

BACKGROUND: Repeated inhalation of allergen at low-dose induces an increase in bronchial hyper-responsiveness, without any associated symptom. The concomitant events in the bronchus have not been described. OBJECTIVE: We have studied the dynamic number of mast cells in the airways of patients with mild asthma before and after repeated inhalation of allergen at low-dose and the expression of nerve growth factor (NGF), which is reported to promote growth and survival of mast cells. METHODS: Twelve patients with mild asthma to cat allergen were enrolled at random in a blind placebo-controlled study, and submitted to repeated low-dose allergen exposure (1/5 of the provocative dose). Mast cells were immunolocalized using an antibody against mast cell tryptase. NGF and its high affinity receptor, TrkA, were immunolocalized using anti-NGF and anti-TrkA antibodies, respectively. NGF mRNA was quantified by competitive polymerase chain reaction (PCR) after reverse transcription of total RNA extracted from bronchial biopsy. NGF protein levels were measured by ELISA in bronchoalveolar lavage (BAL) fluid. RESULTS: Bronchial mast cell number was increased significantly after allergen exposure as compared with before. NGF expression in the bronchus was immunolocalized mainly to epithelial cells, but also to fibroblasts, blood vessels, and a few infiltrated cells. NGF mRNA levels in bronchial biopsies were increased significantly after allergen exposure. The high affinity receptor for NGF, TrkA, was immunolocalized to the infiltrated mast cell membrane. CONCLUSION: Our study shows that the increase in the number of mast cells and in the expression of NGF induced by allergen exposure in the bronchus of asthmatic patients is occurring before the onset of symptoms. In addition, our finding of the presence of the TrkA receptor on the membrane of the infiltrated mast cell in situ brings evidence of the mast cell as a target cell for the growth factor activity of NGF in the airways in asthma.

Administration, Inhalation↗
PubMed1999

The growth and the control of human immunodeficiency virus in the lung: implications for highly active antiretroviral therapy.

In recent years, it has become apparent that the lung is an important niche for the proliferation of human immunodeficiency virus (HIV), which may have implications for highly active antiretroviral therapy (HAART). The lung itself is a major site for the opportunistic infections associated with the progression to acquired immune deficiency syndrome (AIDS), specifically Pneumocystis carinii, Myobacterium tuberculosis and pyogenic bacteria. These cases of active pulmonary complications are direct indicators of enhanced progression to AIDS-defining illness and increased morbidity and mortality. It is therefore essential that the interaction between the lung and HIV is fully understood. Recent research indicates the lung may be a major sanctuary for the virus, with distinct evolution and replication in contrast to other target organs for HIV. In this review, we will discuss the recent findings of HIV infection, evolution, host factors involved in the control of HIV within the lung and the impact this may have on current therapy.

AIDS-Related Opportunistic Infections↗
PubMed1997

Role of bronchoalveolar lavage in predicting survival of patients with human immunodeficiency virus infection.

In this multicenter study, we investigated the prognostic factors that influence the risk of death in patients with human immunodeficiency virus (HIV) infection. Clinical and laboratory indices obtained from 161 HIV-seropositive patients who underwent a detailed morphologic and immunophenotypic evaluation of bronchoalveolar lavage (BAL) and peripheral blood cell populations were retrospectively analyzed. In 155 patients, death occurred within the 48-mo follow-up (mean follow-up: 14.8 mo; range: 1 to 48 mo). In the univariate analysis, the patient's age (> 30 yr), HIV disease status, HIV transmission category, number of opportunistic pathogens isolated from the BAL, percentage of BAL neutrophils, and low number of BAL CD4 T cells were predictive of increased mortality. In contrast, the presence of an alveolitis or an increase in the numbers of alveolar macrophages and CD3 T cells was associated with a decreased mortality. In the multivariate analysis, significant independent predictors were age, risk factor for HIV, and presence of an alveolitis. Furthermore, patients with a low number of BAL CD4 T cells had a particularly poor prognosis while the CD4 T-cell count in the peripheral blood (< 50 cells/mm3 in the majority of our patients) had a negligible effect on predicting survival. Our findings suggest the clinical utility of BAL analysis in patients infected with HIV.

AIDS-Related Opportunistic Infections↗
PubMed1996

High-volume, zero-balanced hemofiltration to reduce delayed inflammatory response to cardiopulmonary bypass in children.

BACKGROUND: In previous studies, researchers suggested a beneficial role of hemofiltration performed during cardiopulmonary bypass in children. This study was performed to assess both clinical effects and inflammatory mediator removal by high-volume, zero-fluid balance ultrafiltration during rewarming (Z-BUF). METHODS: Twenty children undergoing cardiac surgery were assigned randomly to Z-BUF or a control group. Plasma C3a, interleukin (IL)-1, IL-6, IL-8, IL-10, tumor necrosis factor, myeloperoxidase, and leukocyte count were measured before (T1) and after (T2) hemofiltration and 24 h later (T3). The intensive care unit staff was blinded to the patient's group. Postoperative alveolar-arterial oxygen gradient, time to extubation, body temperature, and postoperative blood loss were monitored. RESULTS: Ultrafiltration rate was 4,972 (3,183-6,218) mL/m2 (median [minimum-maximum]) in the Z-BUF group, where significant reductions were observed in postoperative blood loss, time to extubation (10.8[9-18] vs. 28.2 [15-58] h) and postoperative alveolar-arterial oxygen gradient (320 [180-418] vs. 551 [485-611] mmHg at T3). In the Z-BUF group, significant removal of tumor necrosis factor, IL-10, myeloperoxidase, and C3a were observed at T2. Interleukin 1, IL-6, IL-8, and myeloperoxidase were decreased at T3, suggesting earlier removal of factor(s) that may trigger their release. CONCLUSIONS: These results suggest that hemofiltration exerts some beneficial clinical effects that are not due to water removal. The role of the early removal of factors triggering the inflammatory response, rather than a direct removal of cytokines, deserves further investigation.

Anesthetics↗
PubMed1996

Bronchiolitis obliterans organizing pneumonia associated with chlamydial infection.

A 70 year old man presented with symptoms and laboratory findings suggestive of chlamydial pneumonia. Despite adequate antibiotic therapy, his condition did not improve and transbronchial biopsies disclosed a typical feature of bronchiolitis obliterans organizing pneumonia (BOOP). After initiation of corticosteroid therapy, there were marked clinical and radiographic improvements. This report demonstrates that chlamydial infection may be associated with BOOP.

Aged↗
PubMed1993

Biologic response to anti-CD16 monoclonal antibody therapy in a human immunodeficiency virus-related immune thrombocytopenic purpura patient.

A patient with refractory human immunodeficiency virus (HIV)-related immune thrombocytopenic purpura (ITP) was treated with 3G8 (anti-CD16) monoclonal antibody on days 1, 3, and 8 (25, 25, and 50 mg were administered intravenously, respectively). Side effects were those expected after the administration of a xenogenic protein, but a severe bone pain occurred from the second injection. At the time of the initiation of the treatment the platelet count was 20,000/mm3 and the absolute CD4 number was 100/mm3. We obtained a long-term correction of thrombocytopenia and, to a lesser extent, there was a stabilization of CD4 lymphocytes for 18 months. We observed a significant stimulation of natural killer (NK) function and an elevation in the serum level of tumor necrosis factor alpha, interferon gamma, and granulocyte-macrophage colony-stimulating factor. This suggests that in HIV-related ITP the removal of platelets is mediated by low-affinity Fc gamma receptors (CD16). The stimulation of NK function and elevation in CD4+ lymphocytes may be related to the production of cytokines by activated human NK cells through the interaction of their CD16-bearing receptor with the 3G8 monoclonal antibody. This observation warrants confirmation and further clinical trials.

Acquired Immunodeficiency Syndrome↗
PubMed1993

High concentration of peripheral blood mononuclear cells harboring infectious virus correlates with rapid progression of human immunodeficiency virus type 1-related diseases.

In a cohort of 103 asymptomatic seropositive subjects (Centers for Disease Control and Prevention [CDC] stage II/III) followed for 2 years, the concentration of peripheral blood mononuclear cells harboring infectious human immunodeficiency virus (HIV) type 1 (viral burden) was correlated with the rate of decrease of CD4 cell count (RD-CD4; R = .857). Rapidly progressing patients (RD-CD4 > or = 60%; n = 18) had a high viral burden (mean +/- SE, 572 +/- 202 cells/mL) and an 89% progression to CDC IV-A-C, while stable patients (RD-CD4 < 30%; n = 55) had a low viral burden (mean +/- SE, 28 +/- 4 cells/mL) and remained asymptomatic. Slowly progressing patients (RD-CD4 > or = 30 and < 60%; n = 30) showed an intermediate viral burden (mean +/- SE, 131 +/- 9 cells/mL) and a 10% CDC IV-A-C progression. Quantitative determination of infectious virus in blood cells adds important information on the prognosis of HIV-1 infection.

Adult↗
PubMed1992

[Broncho-alveolar lavage. From technical aspects to standards of interpretation].

Broncho-alveolar lavage is a simple investigation to carry out and enables the gathering of biological information such as inflammatory and immuno-competent cells, tumour cells, microorganisms as well as mineral particles which are found in the biological milieux present in the distal air spaces. The performance of LBA assumes a mastering of the correct technical aspects of this method of investigation, particularly in the phase of injecting and recovering of physiological saline and an understanding of the indications and contraindications of the technique. The interpretation of the information gathered by cytological, microbiological, mineralogical and biochemical study of the bronchoalveolar lavage liquid should comply with a strict set of rules and justifies a close working contact between the clinician and the biological scientist.

Bronchi↗
PubMed1991

Drug-induced lung disease: 1990 review.

Numerous drug-induced pulmonary manifestations have been reported but studies of their pathogenic mechanisms are still rare. These mechanisms should, however, be precisely determined in order to identify subjects at risk and to prevent some of these complications by the proper use of certain drugs in more appropriate conditions. The possibility of an iatrogenic manifestation should always be considered in patients developing pulmonary symptoms. Data from biological investigations, although not specific, contribute to the understanding of lung injury mechanisms.

Asthma↗