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P Herve

Publications and source records attributed to P Herve.

At least 55 records · Page 3Linked to original sources
PubMed1993

Evidence of L-arginine/nitric oxide pathway in endothelium and smooth muscle of human internal mammary artery.

UNLABELLED: The L-arginine-nitric oxide (NO) pathway was investigated in human internal mammary artery (HIMA) in vitro. HIMA rings were mounted in organ bath, and then incubated in Krebs buffer for 1 to 8 hrs, relaxing agents were tested. Under these conditions, L-arginine (0.1 microM - 1 mM) elicited only minor relaxation after 2 hr incubation, whereas with increased incubation time (4, 6, 8 hrs), the concentration-dependent relaxation to L-arginine increased significantly in endothelium-intact and -denuded vessels. NG-nitro-L-arginine (100 microM) or NG-monomethyl-L-arginine (100 microM) or methylene blue (2.7 microM) partially inhibited L-arginine relaxation. In endothelium-intact HIMA and in both types of rings A23187 (10 microM) and L-arginine (100 microM), respectively, increased the concentration of NO in medium and cGMP content of vascular tissues. These increases were partially inhibited by NG-nitro-L-arginine (100 microM) or methylene blue (2.7 microM). CONCLUSION: in smooth muscle of HIMA L-arginine-NO conversion is calcium independent, which is different from that in endothelium.

Acetylcholine↗
PubMed1993

Treatment of multiple sclerosis with anti-CD4 monoclonal antibody. A preliminary report on B-F5 in 21 patients.

Twenty-one patients with definite active multiple sclerosis (MS) were treated with a monoclonal anti-T CD4/B-F5 (murine IgG1) antibody for 10 days. Side effects were observed in 11 patients during the first infusion. These side effects were accompanied by and probably related to a transient increase in IL6 and TNF alpha serum levels. This problem led to treatment interruption in one patient. Neither clinical improvement nor deterioration was observed in the course of treatment. EDSS improvement (> 1 point) occurred in six patients one month post-treatment. One month after the end of treatment total lymphocytes and CD3+ and CD4+ cells were significantly decreased. Cytokine analysis performed in serum and in CSF before and after treatment showed no induced modifications. Ten patients developed xenogenic antibodies. It is of interest that the patients with relapsing-remitting forms were relapse-free at the 6th month post-therapy.

Adult↗
PubMed1993

Frequency of mechanical ventilation and respiratory activity after double lung transplantation.

We investigated the contribution of pulmonary afferent nerve fibers to the control of inspiratory activity in awake humans. Eight double lung transplant outpatients and eight normal subjects were hyperventilated with a mechanical ventilator. Respiratory frequency was increased until no respiratory activity was detectable. Then, by either adding CO2 in the inspired gas or decreasing respiratory frequency, end-tidal PCO2 (PETCO2) was increased until inspiratory activity (i.e. change in inspiratory airway pressure peak and/or time profile) was detected. In normal subjects, PETCO2 threshold for inspiratory muscle recruitment was significantly lower when frequency was decreased than when CO2 was added (31.3 +/- 6.8 Torr vs. 38.2 +/- 8.1 Torr respectively, P < 0.005). This was not the case in the double lung transplant group (31.5 +/- 6.5 Torr vs. 32.9 +/- 5.8 Torr). These findings suggest that pulmonary afferent nerves have an inhibitory effect on inspiratory activity in humans.

Adult↗
PubMed1993

Immunological characteristics of umbilical cord blood cells: phenotypic and functional analysis.

The purpose of this study was to phenotype and assay immunological function on cord blood from 70 samples. Immunophenotyping indicated similar numbers of CD2, 3, and 8-positive cells as in adult bone marrow. CD4-positive cells were increased and CD19, 20, and CD56-positive cells were decreased in numbers. Proliferative responses to nonspecific mitogens were lower in cord blood cells than in adult cells, as was NK activity and spontaneous secretion of IL-6 and TNF-alpha. This study confirms the relative immaturity of cord blood cells even when some functional assays appear normal.

Adult↗
PubMed1993

Primary pulmonary hypertension and fenfluramine use.

Not all the risk factors for primary pulmonary hypertension (PPH) are known. Appetite suppressants, including fenfluramine derivatives, are strongly suspected aetiological agents. In a 5 year retrospective study fenfluramine use was evaluated among patients referred to a medical centre specialising in the management of PPH. Fifteen (20%) of 73 patients with PPH had used fenfluramine: all of them were women and in 10 (67%) there was a close temporal relation between fenfluramine use and the development of exertional dyspnoea. Initial right heart catheterisation in the 15 women showed severe resting pulmonary hypertension (mean (SD)) with pulmonary artery pressure (PAP) 57 (9) mm Hg, cardiac index 2.1 (0.5) l/min/m2, and pulmonary vascular resistance (PVR) 29 (10) U/m2. Short-term epoprostenol infusion produced a significant vasodilator response in 10 patients (mean fall in PVR 24 (15%) compared with control values). Three fenfluramine users with PPH showed spontaneous clinical and haemodynamic improvement 3, 6 and 12 months after drug withdrawal but there was no significant difference in overall survival (transplant recipients excluded) between fenfluramine users and controls. Histological examination of lung tissue from five women who had used fenfluramine and 22 controls, with PPH showed features typical of advanced plexogenic pulmonary arteriopathy in all. These results do not accord with earlier reports that PPH associated with fenfluramine is less severe and has a better outcome. Fenfluramine may be one aetiological agent that can precipitate or hasten the development of PPH. The results of a European case-control study should give new insights into risk factors for PPH and the cause and effect relation with fenfluramine.

Adult↗
PubMed1993

Impairment of bronchial mucociliary clearance in long-term survivors of heart/lung and double-lung transplantation. The Paris-Sud Lung Transplant Group.

The study objective was to investigate bronchial mucociliary clearance after heart/lung and double lung transplantation. Bronchial mucociliary clearance was measured using a noninvasive radioaerosol technique: 99mTc-labeled albumin was aerosolized using a spinning-top generator (mass median aerodynamic diameter, 7.5 mu; geometric standard deviation, 1.5 mu). Radioactivity counts were acquired during 60 min with a gamma camera. A region of interest was drawn over the right lung delineated by a 133Xe lung ventilation image. Bronchial mucociliary clearance was assessed as the percentage of decrease in radioactivity per hour calculated on time-activity curves fitted by a monoexponential model. To exclude patients with acute lung rejection, opportunistic lung infection, and obliterative bronchiolitis, all patients with transplants underwent pulmonary function tests and bronchoscopic examination before clearance measurement. Eight heart/lung and five double-lung nonsmoking transplant patients with normal lung histology were studied 19.3 +/- 4.0 mo after surgery and compared to nine normal nonsmokers. A similar proximal deposition of the aerosol was obtained in patients with transplants and normal subjects; skew values of distribution histograms of aerosol radioactivity counts were 2.1 +/- 0.2 and 1.8 +/- 0.1, respectively, and the ratios between central and peripheral 99mTc radioactivity counts were 2.4 +/- 0.1 and 2.3 +/- 0.2, respectively. No significant difference was observed in bronchial clearance values between patients with heart/lung and double-lung transplants (26.4 +/- 3.0 percent/h vs 35.9 +/- 3.5 percent/h). Conversely, bronchial clearance was significantly lower in transplant recipients (30.0 +/- 2.5 percent/h) than in normal controls (58.7 +/- 6.2 percent/h; p < 0.001). This decreased bronchial clearance can be expected to increase the risk of lung infection in long-term survivors of heart/lung and double-lung transplantation.

Adult↗
PubMed1993

Use of an anti-interleukin-2 receptor monoclonal antibody for GVHD prophylaxis in unrelated donor BMT.

Severe acute GVHD remains the main complication in unrelated donor BMT (UD-BMT). The previous encouraging reports on the use of anti-IL-2 receptor monoclonal Ab (33B31) for GVHD prophylaxis in genoidentical BMT led us to add this Ab to the standard GVHD prophylaxis regimen (MTX plus CsA). Sixty-four consecutive patients received 33B31, 20 mg on days 1 and 2, then 10 mg per day from day 3 to day 28 in association with CsA and MTX. They were compared with a historical control group of 89 patients who received conventional GVHD prophylaxis. The 33B31 was well tolerated. We did not find any statistical difference in terms of incidence and time of onset of severe GVHD, occurrence of chronic GVHD, engraftment, relapse or survival among the two groups. Immunization occurred but did not influence serum levels of 33B31. No correlation was found between the severity of GVHD and serum Ab levels. We conclude that other approaches for reducing acute GVHD should be developed to improve UD-BMT results.

Actuarial Analysis↗
PubMed1993

Toward cord blood banking: density-separation and cryopreservation of cord blood progenitors.

It has been shown that cord blood collected at birth can be used to successfully engraft a human lymphocyte antigen (HLA)-matched sibling suffering from a malignant disease. It has been further suggested that this source of cells may be used in unrelated but HLA-compatible patients. These wide indications would imply the establishment of cord blood banks comprising 10(5) or more samples. In this report we show that it is possible to fractionate and freeze cord blood samples without major loss in granulomonocytic or erythroblastic progenitors (CFU-GM and BFU-E). Density separation should be carried out using Percoll of density 1.080. Separated samples should be frozen and thawed in the presence of DNase I. This procedure should allow the storage of approximately 10 mL samples in cryotubes containing a number of CFU-GM and BFU-E sufficient to engraft a patient weighing less than 30 kg. These data provide a rationale for establishing cord blood banks.

Blood Banks↗
PubMed1992

Lack of bronchial hyperresponsiveness to methacholine and to isocapnic dry air hyperventilation in heart/lung and double-lung transplant recipients with normal lung histology. The Paris-Sud Lung Transplant Group.

To investigate whether survivors of heart/lung and double-lung transplantations have normal or increased nonspecific bronchial responsiveness, nine heart/lung and four double-lung transplant recipients with normal lung histology underwent methacholine challenge and voluntary isocapnic dry air hyperventilation (VIH) in a randomized order at a mean time of 14.8 +/- 12.1 months after surgery. Transplant recipients were compared with 10 normal subjects and 11 patients with mild asthma. Asthmatic patients had a mean provocative concentration of methacholine inducing a 20% fall (PC20) in FEV1 of 3.4 +/- 3.6 mg/ml (SD). Seventy seven percent of the transplant recipients and 70% of the normal subjects had PC20 superior to 32 mg/ml. The percentage fall from baseline FEV1 after VIH was 12.6 +/- 10.4% in asthmatic patients as compared with 1.9 +/- 2.9% in transplant recipients (p = 0.002) and 0.45 +/- 1.2% in normal subjects (p = 0.001). The decrease in FEV1 after VIH was similar in transplant recipients and normal subjects (p = 0.14). These results show that heart/lung or double-lung transplant recipients with normal lung histology have a normal response to nonspecific bronchial stimulation.

Adult↗
PubMed1992

Autologous bone marrow transplantation vs intensive chemotherapy in first complete remission: interim results of GOELAM study in AML.

In November 1987, the French group GOELAM initiated a randomized study comparing allogeneic bone marrow transplantation (BMT), autologous bone marrow transplantation (ABMT) and intensive consolidation chemotherapy (ICC). The induction treatment was randomized between Idarubicin plus Cytarabine and Zorubicine plus Cytarabine: 223 patients with de novo AML and aged 15-50 years are currently evaluable and 178 of them (80%) have achieved complete remission (CR) with no significant difference between both arms. Forty four patients under 40 years of age and having a HLA identical sibling were assigned to BMT and 38 were actually transplanted. Thirty of the 134 other patients did not receive the planned first course of ICC, 4 patients died during this course, and 21 were excluded before randomisation. Thus, only 64 patients have currently been randomized between the 2nd course of ICC (34 patients) and ABMT (30 patients). ABMT was prepared by the Baltimore regimen and the marrow was unpurged. With a median follow-up time of 29 months, the actuarial risk of relapse at 3 years is 29% for BMT, 38% for ABMT and 53% for ICC. The 3 year disease free survival (DFS) is 51% for BMT, 62% for ABMT and 47% for ICC. These differences are not statistically significant. When intention to treat is considered, there is no difference in the actuarial DFS between the BMT and the non BMT groups. Longer follow-up time and larger number of patients are warranted to demonstrate any significant advantage of one of these approaches.

Acute Disease↗
PubMed1991

Granulocyte-macrophage colony-stimulating factor (GM-CSF) in human long-term bone marrow cultures: endogenous production in the adherent layer and effect of exogenous GM-CSF on granulomonopoiesis.

This study was designed to assess the presence of endogenous granulocyte-macrophage colony-stimulating factor (GM-CSF) within adherent layers of human Dexter-type cultures and to investigate the effect on granulomonopoiesis of adding exogenous GM-CSF to the culture medium. The presence of GM-CSF was demonstrated using a bioassay, in which adherent layers from normal bone marrows gave rise to endogenous granulocyte-macrophage colony-forming units (CFU-GM) that were specifically inhibited by increasing amounts of an anti-GM-CSF neutralizing antibody. Using an immunoassay, the estimated amounts of GM-CSF were less than or equal to 40 pg per flask in adherent layers, while remaining undetectable in supernatants. The addition of 10 ng or purified recombinant GM-CSF per milliliter of culture medium increased slightly the CFU-GM output over a 5-week culture period. The addition of 50 ng/mL decreased significantly the CFU-GM output after 5 weeks of culture. This decrease was associated with major modifications of the adherent layer cell composition. Large round or ovoid macrophages were generated at the expense of the interdigitated and elongated stromal cells and the extracellular fibronectin network was no longer observed. These studies suggest that GM-CSF production by accessory cells (stromal cells and/or monocytes) is almost equal to its consumption by hematopoietic cells, a situation similar to that found in long-term cultures of murine marrows. They also show that the maintenance of granulomonopoiesis is decreased by adding more than 10 ng/mL of exogenous GM-CSF to the culture medium, which is related to the induction of adherent macrophages, the disappearance of the major smooth-muscle-like stromal cell component of the adherent layer, and that of the fibronectin extracellular matrix.

Bone Marrow↗
PubMed1991

Influence of the fractionation of total body irradiation on complications and relapse rate for chronic myelogenous leukemia. The Groupe d'Etude des greffes de moelle osseuse (GEGMO).

One hundred eighty patients with chronic myelogenous leukemia, who received an unmanipulated marrow graft from an Human Leucocyte Antigen identical sibling donor, were reported to our group (G.E.G.M.O.) by 21 transplant teams. All were grafted after a total body irradiation-cytoxan conditioning regimen. Of these 180 patients, 126 were non-randomly assigned to single dose total body irradiation (STBI group) and, 54 to fractionated total body irradiation (FTBI group). With a median follow-up of 40 months, there is no statistically significant difference in the 5-year survival rate between the two groups (51% for the whole population). In a first step we demonstrate by multivariate analysis that total body irradiation fractionation can dramatically decrease the incidence of interstitial pneumonitis. However, a multivariate analysis of potent risk factors for relapse post-transplant strongly suggests that TBI fractionation is also linked to an increased relapse rate. So, a sparing effect of fractionation for lung tissue could be offset by a less effective leukemic stem cell kill. Those results from a retrospective, non-randomized, multi-institutional study clearly need additional clinical data, ideally from a randomized study.

Bone Marrow Transplantation↗