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P Feugier

Publications and source records attributed to P Feugier.

At least 37 records · Page 2Linked to original sources
PubMed2001

Quantitative expression of adhesion molecules on granulocyte colony-stimulating factor-mobilized peripheral blood, bone marrow, and cord blood CD34+ cells.

The purpose of this study is to investigate the function of the main adhesion receptors on CD34(+) cells during hematopoietic stem cell transplantation. Expression was quantified by flow cytometry using calibration beads. CD34(+) cells were isolated from either bone marrow (BM), cord blood (CB), or peripheral blood (PB) from study patients and a control group after granulocyte colony-stimulating factor (G-CSF) administration. The study of the CD34(+) cell differentiation showed that CD34(+) cells are mainly CD38(+) and HLA-DR(+), whatever the type of harvest. However, quantitative analysis elicited a weaker expression of CD38 on PB and CB CD34(+) cells in comparison to BM CD34(+) cells. The proportions of CD34(+)/CD49d(+) and CD34(+)/CD49e(+) were smaller on PB cells, without quantitative expression variation. This phenotypic variation promotes CD34(+) cells to exit from BM into circulation, inducing the mobilization. The homing of the CD34(+) cells to the BM involves the CD62L receptor. The expression of this receptor was found to be more frequent and stronger on PB cells than on BM or CB cells. The CD11b, CD18, and CD54 receptors are implicated in CD34(+) cell adhesion to BM microenvironment. No significant variation in CD34(+)/CD11b(+) and CD34(+)/CD18(+) cell frequency was noted. Moreover, the CD54 receptor was more frequently expressed on CB and PB cells. Quantitative analysis revealed that CD18 was more strongly expressed on BM than on PB cells to promote progenitors adhesion by interacting with stromal cells. Finally, the quantitative expression of the main receptors on CD34(+) cells explained cellular functions during the different steps of hematopoietic stem cells transplantation.

ADP-ribosyl Cyclase↗
PubMed2001

[Vascular risk and total hip arthroplasty].

PURPOSE OF THE STUDY: Though exceptional, there is a real risk of vascular complications during total hip arthroplasty procedures. The gravity of these iatrogenic accidents results from their high mortality (7%) and possible functional sequelae (19%). MATERIAL AND METHOD: We report a retrospective multicenter study of 14 vascular complications, six of which occurred during revision surgery for total hip arthroplasty. We assessed risk factors and identified situations of major risk related to acetabular revision: intrapelvic dislocation, protrusion with no bony barrier, and presence of intrapelvic foreign bodies. We advocate the retroperitoneal approach for acetabular revision in case of intrapelvic dislocation or anomalous vessel size or trajectory on the preoperative arteriography. This approach allows ablation of the implants under visual control of the iliac vessels. RESULTS AND DISCUSSION: A careful preoperative work-up is essential to avoid arterial or venous injury. A perfect knowledge of the vessel trajectories and their projection on the acetabulum is crucial. Indeed, such vascular complications are never expected and transform a well-programmed functional procedure into an emergency procedure with the inherent risks. We recall that such accidents may be expressed well after closing and the importance of careful surveillance before, during and after the surgical procedure.

Aged↗
PubMed2000

Vasodilatory response of border zones to acetazolamide before and after endarterectomy : an echo planar imaging-dynamic susceptibility contrast-enhanced MRI study in patients with high-grade unilateral internal carotid artery stenosis.

BACKGROUND AND PURPOSE: The importance of hemodynamic changes related to a high-grade internal carotid artery (ICA) stenosis remains a matter of controversy. Areas between the vascular territories of major cerebral arteries, namely, the border zones, may be selectively vulnerable to hemodynamic alteration. The aim of this study was to search for any hemodynamic impact of carotid endarterectomy (CEA) on vasodilatory response, in particular, within the border zones, by means of multislice dynamic susceptibility contrast MRI. METHODS: Thirteen patients with a high-grade unilateral ICA stenosis (>80%) were examined. Relative regional cerebral blood volume (rrCBV) was determined separately for white matter, gray matter, and anterior and posterior border zones by the acetazolamide test. A vasomotor reactivity index was evaluated from the rrCBV values. Values from the ipsilateral hemisphere were compared with contralateral ones, before and after CEA. RESULTS: Before CEA, rrCBV values in the anterior border zones were significantly (P<0.05) higher in the ipsilateral hemisphere than in the contralateral hemisphere. A decrease in vasomotor reactivity indexes was also observed in the lesion side, but the difference from the contralateral side was not statistically significant. In posterior border zones, no differences in rrCBV or vasomotor reactivity were found between the ipsilateral and the contralateral hemispheres. After CEA, the rrCBV asymmetry in the anterior border zones cleared. CONCLUSIONS: High-grade ICA stenosis with efficient primary collateral pathways may have an early limited hemodynamic impact within border-zone areas. The favorable course of these abnormalities after surgery suggests an additional benefit of CEA at this stage.

Acetazolamide↗
PubMed1999

[Total hip arthroplasty. Risk factors and prevention of iatrogenic vascular complications].

Vascular injuries during orthopaedic hip surgery are rare. However, they must always be feared because they threaten life and limb. We present 11 vascular injuries observed over a 12-year period. Seven women and 4 men, treated by elective surgery, presented 14 vascular injuries (6 arterial, 5 venous and 3 prosthetic vascular graft). Four injuries occurred during revision procedures. They were all operated as an emergency for ischaemic syndrome (6 cases) and/or haemorrhage (7 cases). Four patients (37%) died and 4 developed sequelae, various directly attributable to the vascular injury. In the light of these cases, we tried to determine the various mechanisms of the injury and the orthopedic and vascular risk factors. Preoperative detection and well defined therapeutic rules are very important for the prevention of these severe vascular accidents.

Adult↗
PubMed1997

Acetabular anatomy and the relationship with pelvic vascular structures. Implications in hip surgery.

Most direct vascular trauma occurring during hip surgery results from injury to pelvic vascular structures which are not visible during the procedures of reaming, drilling holes or the fixation of screws. In this study, 5 pelves of fresh cadavers were injected with a radiopaque mixture and were visualised with a scanner according to 5 predetermined sections. Bone depth of the acetabulum was measured in each section. A calculation was made describing the minimal distance separating the inner cortex from the principal pelvic vessels. After an anatomic dissection of each pelvis, the relationship between the vessels and screws of the fixation cup, implanted identically on the quadranted acetabulum, was observed. The screws placed in the anterior and inferior quadrants and the center of the acetabulum endangered the external iliac v. and a. and the obturator pedicle. The depth of the periacetabular bone was greater in the superior and posterior quadrants. The inferior gluteal, pudendal and superior gluteal aa. were more than ten mm from the posterior wall. Conversely, the external iliac and obturator pedicles came in contact with the osseous surface on which they lay. A projection of the vessels on the acetabulum was made, and the reproducible character of the acetabular-quadrant system was verified. The superior quadrant offers all the characteristics of a vascular safe zone. A knowledge of these anatomic relationships explain vascular trauma in pelvic fractures and helps to prevent vascular injury in hip surgery.

Acetabulum↗
PubMed1997

Comparison of T cell depletion strategies from bone marrow, umbilical cord and peripheral blood using five separation systems.

The development of bone marrow transplantation in mismatched or matched unrelated donor situations, the recent use of peripheral blood stem cells for allogeneic transplants, the standardization and respect of good methodology practices highlight the need to evaluate new safe methods of T cell depletion (TCD). We have performed 79 in vitro TCD using five techniques: rabbit complement cytotoxicity, CD2-CD7 immunomagnetic depletion, CD5-CD8 panning system, CD34 positive purging and counterflow centrifugation elutriation (CCE). We analyzed these different approaches with regard to the degree of T and B depletion, recovery of progenitors and NK cells. In our hands, the 5 systems evaluated showed a TCD of between 1.3 and 3 log. The CCE, immunomagnetic, complement and panning methods all give similar a TCD of around 2 log. In contrast, we obtained a TCD of approximately 3 log with CD34 positive purging. The progenitor yield was around 50% regardless of the technique used. However, the degree of B and NK cell depletion was dependent on the method: specific TCD resulted in low BCD (under 0.5 log), whereas CCE or CD34 positive purging gave a BCD of greater than 1 log. Moreover, CD34 positive selection resulted in a virtually complete elimination of NK cells. CCE was the only technique allowing isolation of the small lymphocyte population which can be useful for adoptive therapy. To obtain TCD over three logarithms, double purging techniques are necessary. Because specific roles of T cells subsets in engraftment, graft versus host disease, Epstein Barr virus associated B cell lymphoproliferative disorders and disease relapse have not yet been completely elucidated, new techniques such as CD34 positive purging and double purging methods (positive and negative purging) need to be clinically evaluated, especially with respect to peripheral blood stem cells.

Animals↗
PubMed1996

[Uni- and multifocal eosinophilic granulomas in adults. Diagnostic and therapeutic approaches. Apropos of 3 cases].

Unifocal and multifocal eosinophilic granuloma are Langerhans cell histiocytosis of unknown cause. Over the last 10 years, recent insights in pathogenesis and characterization of this pathology have been made. The authors report three cases of adult unifocal and multifocal eosinophilic granuloma. A review of literature underlines diagnostic features and therapeutic aspects of this disease.

Adult↗
PubMed1996

[Leg embolisms: treatment via surgical embolectomy].

Arterial thrombembolectomy with the Fogarty balloon catheter was the standard therapy until now. We present fifty three patients who underwent 63 embolectomies. The rate of leg salvage was 95%, mortality was 18.8%. There is no controversy about the use of the Fogarty balloon catheter in the iliofemoral segment, particularly in patients with acute ischemia. In popliteal and tibial embolic occlusions, associated intraoperative fibrinolytic therapy obtained good results. Percutaneous thrombo aspiration was a complementary technique for few of distal embolic occlusions.

Aged↗
PubMed1995

[Gelatinous transformation of the bone marrow. Apropos of 3 cases].

Gelatinous transformation of the bone marrow is a rare histological lesion usually associated with cachexia. The authors report three new cases, two in anorexia nervosa and the third in Hodgkin disease. A review of the literature underlines association with marrow cell necrosis and provides the most frequent etiologies. Pathogenesis of gelatinous transformation remains unclear and her prognostic depends on etiology.

Adolescent↗
PubMed1995

Development of a criterion for response to therapy at 6 months in multiple myeloma.

UNLABELLED: To investigate the prognostic value of therapy at 6 months on survival in multiple myeloma, to develop a new criterion assessing response to initial therapy at 6 months, and to compare it to a current criterion. The types of initial and 6-month therapy were considered in a prognostic factor analysis in 70 patients treated in routine practice. Using the response to initial therapy defined by the clinician's decision as grouping variable in this group, a discriminant analysis identified the characteristics of responder patients. The validity of the resulting criterion was tested in another test group. Its prognostic ability was compared to the CLMTF criterion (50% M-component reduction from baseline). The therapy at 6 months, reflecting the clinician's appraisal of response to initial therapy, predicted survival significantly. A criterion combining two variables (M-component change and haemoglobin level at 6 months) classified 70% and 72.4% of patients correctly regarding response status in the training and test groups respectively. This criterion was shown to perform better than the CLMTF criterion in predicting survival. CONCLUSION: A new criterion for response to therapy at 6 months, also presented in a nomogram, combines M-component change and haemoglobin level at 6 months.

Aged↗
PubMed1995

The number of circulating CD34 positive cells is the best preleukapheresis parameter for predicting the quality of peripheral blood progenitor cell harvest.

Correlations between different peripheral blood parameters and harvesting yields of stem cells were analysed in 230 leukaphereses performed on 61 patients. According to multivariate analysis, the number of circulating CD34 positive cells was found to provide the best preleukapheresis parameter for predicting the quality of peripheral blood progenitor cell harvest. A high correlation coefficient and small 95% confidence and prediction intervals would indicate the assay of CD34 positive cells in peripheral blood to be a unique tool essential for monitoring the collection of circulating haematopoietic progenitors.

Adolescent↗
PubMed1990

Time-variations of pretreatment peripheral blood S + G2/M-phase size determined by flow cytometry in adult acute myeloid leukaemia.

The circadian and seasonal variations of pretreatment proliferative activity of peripheral blood (PB) as PB S + G2/M-phase size was determined by flow cytometry in 61 adult patients with acute myeloid leukaemia (AML). Pretreatment PB S-phase (p less than 0.002), G2 + M-phase (p less than 0.008) and S + G2/M-phase size are statistically correlated to the time of sampling, with the highest phase size at the end of the day. Time-variations of the blast cell count are slightly significant (p = 0.049). Cytological diagnosis-related differences in S + G2/M-phase (p less than 0.003) and white blood cell count (p less than 0.04) time-variations are observed. For all patients, no seasonal variations can be drawn, but in AML 1 (p less than 0.029) and AML 4-5 patients (p less than 0.003), the circadian variations of S + G2/M are affected by the seasons. The present results suggest that time may be taken into account in the monitoring of chemotherapy in acute leukaemia.

Adult↗
PubMedDate not supplied

Endofibrosis of the iliac arteries: an underestimated problem.

Arterial endofibrosis is a recently discovered artery disease that is specific to endurance athletes. Cycling is the sport that has shown the greatest number of cases. The endofibrosis is located most frequently in the external iliac artery, but other locations must also be sought. Thigh pain during supramaximal exercise and patient questioning provide strong indications. The diagnosis is confirmed when there is concordance of exercise-induced symptoms, a positive exercise test result and discrete arteriographic characteristics. Treatment is based on folate supplements and standardised surgery carried out by an experienced surgical team.

Angiography↗
PubMedDate not supplied

The Paget-Schroetter syndrome.

Primary axillo-subclavian venous thrombosis is pathology of the young working man. It affects above all the main upper limb and arises during a physical activity of the shoulder. Its aetiology is complex and multifactorial. It is most often the consequence of a chronic compression of the subclavian vein at the level of the thoracic outlet. Clinical presentation can be confirmed with a duplex scan investigation.Early diagnosis offers the opportunity for rapid venous recanalisation with an anticoagulation treatment. A fibrinolytic therapy can be started in the same session of the phlebography. In case of success, a dynamic phlebography is performed to confirm the existence of a venous thoracic outlet syndrome. Even if indications for surgical management of primary subclavian vein thrombosis are still controversial, it is actually clear that this multidisciplinary management of these patients has to be as early as possible. Decompression of the thoracic outlet can be performed secondarily using various techniques including first-rib resection. Should this approach fail to re-establish patency, leaving some residual disabling of the arm, axillo-subclavian vein revascularization can provide good mid-term results.

Adult↗