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F Picard

Publications and source records attributed to F Picard.

At least 109 records · Page 6Linked to original sources

ERBB2 gene amplification detected by fluorescent differential polymerase chain reaction in paraffin-embedded breast carcinoma tissues.

For quantificative determination of ERBB2 gene amplification in archival human carcinoma specimens we have developed a rapid, non-radioactive approach, which is based on the differential polymerase chain reaction (PCR) and fluorescent DNA technique. Sequences from the ERBB2 gene and from a single-copy reference gene were amplified simultaneously by PCR, in which one of each primer pair was fluorescently labelled. PCR products were separated by polyacrylamide gel electrophoresis in an automated DNA sequencer and directly quantified after laser activation and emission scanning using appropriate software. This fluorescent differential polymerase chain reaction (fd-PCR) method was used for quantificative determination of ERBB2 gene amplification in 195 formalin-fixed, paraffin-embedded breast carcinoma tissues. ERBB2 gene amplification was found in 52 (26%) of these tumors and correlated significantly with tumor size, absence of estrogen receptor (ER) and pS2 expression, but not with absence of progesterone receptor (PR) or presence of epidermal growth factor receptor (EGF-R) expression, lymph-node metastases or grading. In univariate analysis, ERBB2 gene amplification showed no significant correlation with clinical outcome, either in the whole population or in the subgroup defined by positive axillary lymph-node metastases. However, within the node-negative subgroup, patients with ERBB2 gene amplification had significantly decreased relapse-free survival and overall survival (p < 0.05). The fd-PCR assay is a valuable tool for determination of amplification of ERBB2 gene as well as further oncogenes. In this way, more detailed information about individual tumor biology may be acquired by a routine assay.

Analysis of Variance↗

Highly purified primitive hematopoietic stem cells are PML-RARA negative and generate nonclonal progenitors in acute promyelocytic leukemia.

The hierarchical level of stem cell involvement in acute promyelocytic leukemia (APL) characterized by the pathognomonic PML-RARA fusion gene is unknown. To determine if the cells of the primitive hematopoietic stem cell compartment are involved in the leukemic process, we have used molecular and cell sorting techniques in peripheral blood and bone marrow (BM) cells at diagnosis from three patients with APL and t(15; 17). In two of them, clonality analysis was also possible using the BstXI polymorphic site of the PGK gene. The PML-RARA fusion gene was readily identified by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of BM cells obtained at diagnosis in all three patients. These same samples were then used to sort CD34+ cells and their CD38+ and CD38- subsets by fluorescence-activated cell sorting. In both female patients, CD34+/CD38+ and CD34+/CD38- cell fractions were polyclonal using PCR, whereas a monoclonal pattern was identified at the BM sample obtained at diagnosis either by Southern blotting or by PCR. Because of the high sensitivity of the PCR analysis, the polyclonal pattern of these cell populations could mask the presence of a minor clone. To detect this clone, we preformed RT-PCR analysis for t(15; 17). In one female patient, the abnormal PML-RAR fusion gene was found only in the more mature CD34+/CD38+ cell fraction using a nested PCR approach, whereas the polyclonal CD34+/CD38- fraction was PML-RARA negative. These findings were confirmed in a third patient with APL in whom the PML-RARA transcripts were absent in the CD34+/CD38- cell fraction. To study the clonality at the level of clonogenic progenitors, we used in one patient PGK analysis by PCR of individual burst-forming units-erythroid and colony-forming units-granulocyte-macrophage obtained from the CD34+/CD38- and CD34+/CD38+ cell populations at diagnosis and from the BM sample obtained during remission. The two highly purified cell populations gave rise to morphologically normal colonies clonal for both the BstXI site containing (A) and the BstXI site lacking (B) PGK allelles, indicating their polyclonal content, a pattern that was also found in clonogenic progenitors obtained at remission. These findings strongly suggest that the primitive hematopoietic stem cells as defined by the CD34+/CD38- antigens are not involved by the neoplastic process in APL. These results may have important implications for autografting strategies of retinoic acid/chemotherapy-resistant or relapsed patients.

ADP-ribosyl Cyclase↗

Detection of the chromosome 16 CBF beta-MYH11 fusion transcript in myelomonocytic leukemias.

Karyotypic detection of chromosomal 16 abnormalities classically associated with AML M4Eo can be difficult. Characterization of the two genes involved in the inv(16)(p13q22), CBF beta and MYH11, has allowed the detection of fusion transcripts by reverse-transcriptase polymerase chain reaction (RT-PCR). We have analyzed CBF beta-MYH11 fusion transcripts by RT-PCR in myelomonocytic leukemias, with or without eosinophilia, to determine whether their presence correlates with morphology. Fifty-three cases (11 AML M4Eo; 1 AML M4 with atypical abnormal eosinophils (AML M4 "Eo"); 29 AML M4; 8 AML M5; 3 CMML; and 1 AML M2 with eosinophilia) were analyzed. All 11 typical AML M4Eo were CBF beta-MYH11 positive. The single case of AML M4 with distinctive eosinophil abnormalities was negative by karyotype, RT-PCR and fluorescent in situ hybridization (FISH). Three of 29 (10%) AML M4 without abnormal eosinophils were CBF beta-MYH11 positive, 1 of which did not show any apparent chromosome 16 abnormalities by classical metaphase analysis (2 not tested). Both cases tested also showed MYH11 genomic rearrangement. None of the other leukemias were RT-PCR positive. Follow-up of three patient showed residual positivity in apparent complete remission. These data show that CBF beta-MYH11 fusion transcripts occur not only in the vast majority of typical AML M4Eo, but also in approximately 10% of AML M4 without eosinophilic abnormalities, a much higher incidence than the sporadic reports of chromosome 16 abnormalities in AML M4 would suggest. Taken together with the detection of CBF beta-MYH11 transcripts in the absence of apparent chromosome 16 abnormalities by classical banding techniques, these data show that additional screening by either RT-PCR or FISH should be performed in all AML M4, regardless of morphologic features, to allow accurate evaluation of the prognostic importance of this fusion transcript.

Adolescent↗

[Prenatal determination of fetal rhesus factor in amnionic cells using polymerase chain reaction].

In Rhesus incompatibility, prenatal RhD typing of the fetus requires intrauterine blood sampling by cordocentesis or by chorionic villus biopsy. Amniocentesis is easier to perform, and carries a lower risk of enhancement of maternal immunization. Therefore, we evaluated polymerase chain reaction (PCR) for fetal RhD typing in amniocytes which were isolated from amniotic fluid (18-40 gw) obtained by amniocentesis (n=26) or during delivery (n=27). In the clinically most important group of children from RhD-negative women (n=25) and in 28 newborns of RhD- positive mothers, we found a 100 percent agreement between the findings of PCR and the results of serologic typing. If these encouraging results are confirmed in a larger series, the method could be used for the clinical management of RhD-negative women with Rhesus incompatibility and a heterozygous RhD-positive partner.

Amniocentesis↗

Thrombopoietin is not responsible for the thrombocytosis observed in patients with acute myeloid leukemias and the 3q21q26 syndrome.

Patients with acute myeloblastic leukaemia (AML) and chromosomic abnormalities of the 3q21;q26 region have striking dysmegakaryopoiesis and normal or increased platelet counts. Leukaemic cells ectopically express the Evi-1 gene which maps to human chromosome 3q26:q27. Thrombopoietin (TPO) has been cloned recently and shown to be the major hormone stimulating both megakaryocytopoiesis and thrombopoiesis. The TPO gene maps to human chromosome 3q26. For this report we studied four patients with typical 3q21:q26 syndrome. Karyotype analysis showed inv(3)(q21;q26) in three cases and t(3:3)(q21;q26) in one case. Although high levels of Evi-1 transcripts could be detected in mRNA isolated from the bone marrow cells of these patients by Northern blot analysis, no TPO transcripts were detectable by RT-PCR technique on the same mRNA samples. These results demonstrate that TPO gene transcription is not activated in patients with 3q26 chromosomic abnormality, and that abnormal TPO production is not responsible for the observed thrombocytosis.

Acute Disease↗

Iatrogenic hallux varus surgical procedure: a study of 14 cases.

Hallux varus occurs most frequently as a result of excessive surgical correction of musculoligamentous imbalance around the metatarsophalangeal (MTP) joint of the great toe (lateral release and medial capsuloligamentous tensioning). If untreated, the condition may lead to motion loss and degenerative arthritis. In this series, 14 cases of hallux varus were treated. Medial arthrolysis was done in each case. In five cases, reconstruction of the lateral ligament (with a 1.5-mm Ligapro suture), using a new technique, accompanied the medial release. Arthrodesis of the MTP was done in nine cases treated when there was already stiffness and arthrosis. According to a 100-point scoring system, the results were excellent in 56% and good in 44% of the MTP joint arthrodesis cases. Results were excellent in 100% of the mobilizing technique cases using Ligapro suture.

Adult↗

c-mpl expression in hematologic disorders.

The c-mpl gene encodes a member of the hematopoietic cytokine receptor superfamily. This gene was discovered through the study of a murine retrovirus which induces an acute myeloproliferative syndrome in mice. MPLV (for myeloproliferative leukemia virus) has transduced a truncated and constitutively activated form of the c-mpl receptor chain. The c-mpl ligand is unknown, but recent data indicate that it could specifically regulate thrombocytopoiesis. This review focuses on the expression of the c-mpl gene in a large series of human hematopoietic pathologies by Northern blot analysis. Barely detectable transcript levels were detected in normal bone marrow (BM) and in BM samples from chronic myeloproliferative disorders, plasmocytoma, Burkitt lymphoma or acute lymphoid leukemia. In contrast, high levels of c-mpl expression were detected in 45% of acute myeloid leukemia (AML). No correlation was found between c-mpl expression and the French-American-British classification subtype of AML. However c-mpl expression correlated with CD34 expression, and unfavorable cytogenetic abnormalities, defining a subgroup of AML with a low rate of complete remission. In myelodysplasia, c-mpl expression was elevated in 44% of chronic myelomonocytic leukemia (CMML), 42% of refractory anemia with excess myeloblasts (RAEB), and RAEB in transformation to acute leukemia (RAEBt), but not in refractory anemia (RA) and RA with ringed sideroblasts (RARS). In CMML, there was no correlation between c-mpl expression and any prognostic factor tested, nor with the course of the disease. The biologic significance of c-mpl expression in RAEB and RAEBt is probably different.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Polymyositis associated with Ki-1 lymphoma.

We report here a case of acute polymyositis associated with a Ki-1 non-Hodgkin's lymphoma (NHL). This anaplastic large cell malignant lymphoma was a primary T-cell NHL lymphoma of the bone marrow. The malignant cells expressed the CD30 (Ki-1), CD3, and CD4 antigens, the beta chain of the interleukin 2 receptor (CD25), and the betaF1 antigen (alpha/beta T-cell receptor). Chemotherapy and high dose methylprednisolone pulse therapy were initiated. However, no clinical improvement was noticed, because the patient rapidly died of an acute respiratory distress syndrome. To our best knowledge, this represents the first case of Ki-1 lymphoma associated with Polymyositis.

Acute Disease↗

Prognostic value of c-mpl expression in myelodysplastic syndromes.

The c-mpl proto-oncogene which encodes a member of the hematopoietic cytokine receptor superfamily has been recently shown to be the receptor for thrombopoietin (TPO), which stimulates megakaryocyte progenitor expansion and differentiation. We studied c-mpl expression by Northern blot analysis, in a large series of 58 MDS. No expression was found in 14 patients with refractory anemia (RA) or with refractory anemia with ring sideroblasts (RARS). In contrast 11/26 (42%) patients with refractory anemia with excess of blasts (RAEB), or with RAEB in transformation (RAEBt), and 8/18 (44%) patients with chronic myelomonocytic leukemia (CMML) expressed c-mpl. In CMML patients, no correlation was found between c-mpl expression and any prognostic factor tested, nor with the course of the disease. In contrast, in RAEB and RAEBt, expression of c-mpl was correlated with high Bournemouth scoring (P < 0.005) and poor survival (P = 0.02) due to leukemic transformation. Forty-five per cent (5/11) of the c-mpl positive patients evolved towards AML with a mean follow-up of 10.5 months, while 13% (2/15) of the c-mpl negative patients developed a secondary leukemia, with a mean follow-up of 21.1 months. Moreover, in RAEB and RAEBt, a significant correlation was observed between c-mpl, CD34, megakaryocyte glycoprotein IIb (GPIIb) expression, and the presence of dysmegakaryopoiesis. These results indicate that patients with RAEB and RAEBt, with high expression of the c-mpl, CD34, and GPIIb genes, may identify a subgroup of patients with particularly poor prognosis, due to an increased risk of secondary leukemia. More aggressive therapy could be justified in these patients.

Antigens, CD↗

[Isolated rupture of the tendon of the supra spinatus muscle. Results of 49 surgical repair].

PURPOSE OF THE STUDY: The purpose of this study was to assess the results of surgical repairs in 49 << isolated >> tears of the supra- spinatus in 49 patients, 32 males and 17 females. MATERIAL AND METHODS: The average age at operation was 54,2 years (35 to 72) and the dominant side was injured in 30 patients (12 opposite side and 5 unknown). According to Constant's score the pain was permanent in 23 patients, it occurred at moderate exertion in 21 patients and at important exertion in 5. The average pain duration was 43,4 months (0 to 360 months). The range of motion was normal (40 points) in 24 patients, diminished in 15 (30 points), very diminished (10 points) in 7 and the shoulder was stiff in one patient (2 files were uncomplete). All the patients were disturbed in daily living activity and the strength assessment was disturbed because of the pain. In all cases we performed an anterior acromioplasty. At operation, 39 patients had an isolated tear of the supra-spinatus and 10 an associated tear of the long head of the biceps (7 tendinities, 1 dislocation and 2 ruptures). The size of the rupture was less than 2 cm2 in 21 cases comprised between 2 and 5 cm2 in 27 and greater than 5 cm2 in one case. The surgical procedure was a Neviaser's technique in 4 cases, a single suture in 19, a transosseous suture in 19 and a deltoid muscular flap in 7 cases (large retracted tear), in addition we performed 14 resections of the distal end of the clavicle and 4 tenodesis of the long head of the biceps. RESULTS: The results were assessed according to Constant's score on 46 patients (3 lost to follow-up), the average follow-up was 31,5 months (12 to 86). The average scores were: pain 12,3 points (3 to 15), range of motion 35,5 (14 to 40), daily living activity 17,4 (8 to 20), and strength 11,4 (< > side = 14,8 points). The total Constant's scores were 75,7 per cent (actual score) and 88,3 per cent (weighted score), according to the weighted score 24 patients had 100 per cent; 9 were comprized between 85 and 100, 5 between 65 and 85, and 8 were less than 65 per cent. The average post-operative acromio-humeral height was 9,84 mm (pre-operative height = 11 mm). DISCUSSION - CONCLUSION: If we compare the results in terms of surgical procedure the difference was not statistically significant although the transosseous suture was not so good: single suture 91,5 per cent, deltoid muscular flap 90,9 per cent, Neviaser's technique 87 per cent, and transosseous suture 79,1 per cent. Nevertheless the results are not so good (p = 0,01) if it is an industrial injury and if the post operative acromio-humeral height is diminished. On the other hand, age, sex, duration of the pain, occupation, tenodesis of the long head of the biceps and resection of the distal end of the clavicle don't have any pejorative influence on the results.

Acromion↗

[Restoration of opposition using the extensor pollicis longus. Apropos of 8 cases reviewed after 11 years].

Moutet and coll. had studied in 1986 a series of 16 cases of restoration of thumb opposition by extensor pollicis longus transfer onto abductor pollicis brevis through the inter osseous membrane. Eleven years follow-up revision of 8 of those 16 patients was performed by the authors. Indication of transfer was traumatic median nerve isolated palsy or associated to ulnar nerve palsy. Objective and subjective analysed parameters allowed to check the evolution of the transfer and to justify its indications. No transfer retraction has been noted in long term follow-up. The side effects of its removal (thumb retropulsion and MP extension defects) have minimum functional consequences. The opposition has been restored at the time of thenarians recovery and as well, each time the palsy was going on. In the cases where the thenarians recovered, the transfer became an antepulsion supply. The authors suggest to perform an opposition transfer, each time it is technically possible, in severe median nerve lesions, at the time of emergency operation.

Adolescent↗

A spontaneous remission of lymphoid blast crisis in chronic myelogenous leukaemia following blood transfusion and infection.

We report a case of spontaneous remission of lymphoid blast crisis in chronic myelogenous leukaemia (CML) which returned to chronic phase, without the use of cytostatic chemotherapy, following an episode of viral infection and blood transfusion. Although complete remissions of acute leukaemia have been described, this evolution is extremely rare and has never been reported in CML blast crisis. The role of hypothetical factors leading to such a rare event are briefly discussed.

Aged↗

The significance of the pre-challenge immune status of mice for development of retrovirus-induced immunodeficiency syndrome (MAIDS).

The effects of vaccination with RNA-free viral pseudoparticles, preinfection with non-pathogenic ecotropic virus, and induction of tolerance to viral proteins in newborns on the outcome of murine immunodeficiency syndrome (MAIDS) were studied. The parameters used to follow disease progression were: lymphopenia, circulating B and T8 cells, serum IgG and IgM levels, lymphoproliferation and skin graft rejection. Immunization with RNA-free viral pseudoparticles had no effect on any of these parameters. Preinfection of adults with ecotropic virus and the induction of tolerance in newborns to virus antigens both attenuated the early symptoms of viral infection and delayed the onset of immunodeficiency and lymphoproliferation in some mice, but did not significantly alter the number of deaths due to MAIDS. Failure of immune-based therapy to produce successful protection against MAIDS suggests that immune destruction caused by the persistent virus rather than hyperimmune activity is the main pathogenic factor in this disease.

Animals↗

[Anterior instability of the shoulder associated with fracture of the coracoid process. Apropos of 3 cases].

PURPOSE OF THE STUDY: The aim of this paper is to present an unusual lesion associating anterior instability of the shoulder with a fracture of the horizontal part of the coracoid process. It emphasizes surgical treatment using the Latarjet procedure. MATERIAL AND METHODS: Three cases are presented: One case was a recurrent anterior dislocation of the shoulder associated with a fracture of the horizontal part of the coracoid process; an other case was a painful shoulder associated with pseudarthrosis of the coracoid process and a fracture of the anterior and inferior edge of the glenoid. In the last case there was a recurrent dislocation of the shoulder associated with a pseudarthrosis of the coracoid process detected intra-operatively. All the patients were operated on using the Latarjet's procedure using the fractured coracoid process. RESULTS: The three cases had a good result. DISCUSSION: The association of an anterior dislocation of the shoulder and a fracture of the coracoid process is very unusual. It is often unrecognized because of poor knowledge of this lesion or a poor quality of the radiograms performed in the emergency room. The most likely mechanism is a direct impact of the humeral head against the coracoid process during the dislocation. The fracture is located (as in our 3 cases) at the horizontal part of the coracoid process near its elbow and they are often associated lesions at the anterior and inferior edge of the glenoid. The diagnosis requires good quality radiograms and a Garth's view systematically performed after reducing the dislocation. When the shoulder is painful or unstable, surgical treatment is performed and the Latarjet's procedure takes care of the pseudarthrosis and the instability of the shoulder. CONCLUSION: Isolated fractures of the coracoid process are probably uncommon. When there is a fracture of the horizontal part of the coracoid process anterior instability of the shoulder should be suspected. This is the case when the shoulder has never been dislocated and when the standard radiograms are "normal" without "crossing lesions" at the anterior and inferior edge of the glenoid or at the humeral head (Hill-Sach lesion).

Adolescent↗

Evaluation of the Coulter MAXM in a children's hospital.

An evaluation of the WBC differential given by the analyzer Coulter MAXM was performed in a children's hospital, in order to establish optimal interpretation of the automated MAXM report in pediatrics. The patient group comprised 419 children of age up to 15 years. Assessment was carried out by comparison of the MAXM results with microscopic examination of blood smears, good correlation being observed between the two methods in non flagged samples and those flagged only with an isolated "Imm Grans/Bands 1" message indicating the presence of band cells. Comparison of the MAXM and optical differentials in normal and abnormal samples was performed according to a standard protocol taking into account both suspect flags and quantitative abnormalities defined in relation to age. In this group of 419 children, there were 20 (4.8%) false positive and 8 (1.9%) false negative reports, the 8 false negative results corresponding to either minor morphological (4) or borderline quantitative abnormalities (4). Overall, the instrument was capable of detecting significant abnormalities in blood samples with a sensitivity of 95.5% and a specificity of 91.7%. Although the review rate was 45.3%, the high efficiency (93.3%) suggested that most blood smear reviews led to the discovery of a morphological and/or quantitative abnormality. Furthermore, the review rate was greater in neonates (< 7 days) and infants (7 days-1 year) but closer to those of adult populations in older children. The Coulter MAXM was thus shown to be appropriate for use in pediatrics, despite a higher frequency of blood smear review than in adults, particularly among patients less than one year old.

Adolescent↗