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C Bergeron

Publications and source records attributed to C Bergeron.

At least 127 records · Page 7Linked to original sources
PubMed1996

Ovarian endometrioid tumors with yolk sac tumor component, an unusual form of ovarian neoplasm. Analysis of six cases.

The clinical, morphological, and immunohistochemical findings in six cases of ovarian endometrioid tumors (five endometrioid carcinomas and one carcinosarcoma) with a yolk sac tumor (YST) component are described. The age of the patients ranged from 31 to 73 years (average, 53), and only two patients were premenopausal. Two cases were stage Ia tumors, three stage III, and one stage IV. A substantial postoperative elevation of alpha-fetoprotein (AFP) was seen in two patients and a mild increase in another two. All six patients had surgery and postoperative cisplatin-based chemotherapy regimens, four of whom died of tumor 3 to 14 months after surgery without response to treatment. Only a stage Ia patient is alive and well 1 year after surgery. The tumors were large (average, 17 cm). Benign endometrioid lesions were found in the homolateral ovary in two cases and in the contralateral ovary in another two. All cases had endometrioid ovarian carcinomas (EOC) of various types admixed with typical YST components. Immunohistochemically, EOC areas differed from YST in their positivity for OC 125, CA 19.9, and nuclear estrogen and progesterone receptors and in their negativity for AFP, which was conspicuously positive in the YST areas. The clinicopathological profile of ovarian endometrioid tumors with YST also differs from that of YST in that it occurs in the same age range as EOC, it shows coexistence of benign endometrioid lesions, and it has a poor response to chemotherapy. The histological pattern in transitional areas may be difficult to differentiate from "endometrioid-like" (enteroblastic) YST and clear cell tumors. Ovarian endometrioid tumors with YST component should be considered a variant of endometrial carcinoma. Its recognition is necessary in view of its unusually aggressive behavior and poor prognosis.

Adult↗
PubMed1996

HIV-1, HIV-2, human papillomavirus infection and cervical neoplasia in high-risk African women.

OBJECTIVE: To determine the effect of HIV-1 and HIV-2 infection on the prevalence of cervical human papillomavirus (HPV) and squamous intraepithelial lesions (SIL) in a population of high-risk women in Senegal. DESIGN AND PARTICIPANTS: Cross-sectional study among 759 female commercial sex workers, including 68 with HIV-1, 58 with HIV-2, 14 with HIV-1 and 2, and 619 without HIV infection. RESULTS: Overall, HPV was detected in 43% of women by polymerase chain reaction (PCR), and in 7% by Southern transfer hybridization, with 7.4% of all women having SIL. The mean CD4 count was 820, 1205, and 727 x 10(6)/l for those with HIV-1, HIV-2, and dual HIV-1 and 2 infections, respectively, and 1447 x 10(6)/l for those without HIV infection. Both HIV-1 and HIV-2 were associated with HPV, as detected by PCR [HIV-1 odds ratio (OR), 2.9; 95% confidence interval (Cl), 1.7-4.9; HIV-2 OR, 1.7; 95% Cl, 1.0-2.9]. HIV-2 was also associated with cervical SIL, and although the association between HIV-1 and SIL did not attain statistical significance, a trend was apparent (HIV-1 OR, 1.8; 95% Cl, 0.7-4.7; HIV-2 OR, 2.9; 95% Cl, 1.2-7.2). CONCLUSIONS: Despite less immunosuppression with HIV-2, both HIV-1 and HIV-2 were associated with detection of HPV. HIV-2 was also associated with SIL. Further studies are needed to examine the risks of high-grade SIL and invasive cervical cancer with HIV-1 versus HIV-2 infection.

Adult↗
PubMed1996

Risk for neuropathologically confirmed Alzheimer's disease and residual aluminum in municipal drinking water employing weighted residential histories.

We investigated a possible relation between aluminum concentration ([Al]) in public drinking water and Alzheimer's disease (AD), with AD cases and controls defined on the basis of strict neuropathologic criteria. Using the case/control odds ratio as an estimate of relative risk and [Al] > or = 100 microgram/L as the cutoff point, elevated risks for histopathologically verified AD were associated with higher [Al]. Comparing all AD cases with all non-AD controls, and using the [Al] of public drinking water at last residence before death as the measure of exposure, the estimated relative risk associated with [Al] > or = 100 microgram/L was 1.7 (95% CI: 1.2-2.5). Estimating aluminum exposure from a 10-year weighted residential history resulted in estimates of relative risk of 2.5 or greater. The public health implications of the observed relationship between [Al] in drinking water and AD prevalence in the population depend in large measure on population exposure characteristics. In Ontario, it is estimated that 19% of the population was exposed to residual [Al] greater than or equal to 100 microgram/L. Based on the estimated relative risk and the assumption of causality, this translates to an etiologic fraction of 0.23. Although the potential contributions of confounding and mitigating factors are not defined in this report, the merit of limiting residual aluminum in drinking water supplies deserves serious attention.

Aged↗
PubMed1996

Familial and sporadic Alzheimer's disease: neuropathology cannot exclude a final common pathway.

Whether all etiologic forms of Alzheimer's disease (AD) share a final common pathway is a major issue. We determined the severity and regional distribution of neuronal loss, amyloid plaques, neuritic plaques (NPs), and neurofibrillary tangles (NFTs), and calculated the ratio of neuronal loss to NPs and NFTs in brains of 19 familial AD (FAD) patients with linkage to chromosome 14, six AD patients with mutations of chromosome 21 (codon 717 of the beta-amyloid percursor protein gene), and 11 sporadic AD (SAD) patients. There was no difference in the pattern of distribution of the various pathologic features or in the ratio of neuronal loss to NPs or NFTs in any AD group. However, FAD groups could be distinguished from SAD by the greater severity and the lack of influence of apolipoprotein E genotype on pathology. These differences may reflect differences in age at onset rather than different etiopathologic mechanisms. The similarity of pathologic findings in the different AD groups provides evidence for a final common pathophysiologic pathway in AD.

Age of Onset↗
PubMed1996

Consensus guidelines for the clinical and pathologic diagnosis of dementia with Lewy bodies (DLB): report of the consortium on DLB international workshop.

Recent neuropathologic autopsy studies found that 15 to 25% of elderly demented patients have Lewy bodies (LB) in their brainstem and cortex, and in hospital series this may constitute the most common pathologic subgroup after pure Alzheimer's disease (AD). The Consortium on Dementia with Lewy bodies met to establish consensus guidelines for the clinical diagnosis of dementia with Lewy bodies (DLB) and to establish a common framework for the assessment and characterization of pathologic lesions at autopsy. The importance of accurate antemortem diagnosis of DLB includes a characteristic and often rapidly progressive clinical syndrome, a need for particular caution with neuroleptic medication, and the possibility that DLB patients may be particularly responsive to cholinesterase inhibitors. We identified progressive disabling mental impairment progressing to dementia as the central feature of DLB. Attentional impairments and disproportionate problem solving and visuospatial difficulties are often early and prominent. Fluctuation in cognitive function, persistent well-formed visual hallucinations, and spontaneous motor features of parkinsonism are core features with diagnostic significance in discriminating DLB from AD and other dementias. Appropriate clinical methods for eliciting these key symptoms are described. Brainstem or cortical LB are the only features considered essential for a pathologic diagnosis of DLB, although Lewy-related neurites, Alzheimer pathology, and spongiform change may also be seen. We identified optimal staining methods for each of these and devised a protocol for the evaluation of cortical LB frequency based on a brain sampling procedure consistent with CERAD. This allows cases to be classified into brainstem predominant, limbic (transitional), and neocortical subtypes, using a simple scoring system based on the relative distribution of semiquantitative LB counts. Alzheimer pathology is also frequently present in DLB, usually as diffuse or neuritic plaques, neocortical neurofibrillary tangles being much less common. The precise nosological relationship between DLB and AD remains uncertain, as does that between DLB and patients with Parkinson's disease who subsequently develop neuropsychiatric features. Finally, we recommend procedures for the selective sampling and storage of frozen tissue for a variety of neurochemical assays, which together with developments in molecular genetics, should assist future refinements of diagnosis and classification.

Dementia↗
PubMed1996

Multifactorial drug-resistance phenomenon in acute leukemias: impact of P170-MDR1, LRP56 protein, glutathione-transferases and metallothionein systems on clinical outcome.

The multidrug resistance phenomenon can be observed in cases which do not express the P170 protein and these cases are suspected as having activated different resistance phenomena. Four phenomena were studied at the time of diagnosis in a series of 35 lymphoblastic and 25 myeloblastic acute (de novo) leukemias, by an immunocytochemical method. Two energetic drug transport processes were investigated: the classical MDR/P170 and the P110/LRP56 proteins, and two physiological detoxifying activities such as the glutathione transferases (GST alpha, mu, pi) and the metallothioneins (Mts). The results demonstrate that these phenomena are independent but their synergic activity can increase their impact on the outcome. P110/LRP56 positive cases demonstrated 48.8% complete remission (CR) rate compared to 71.4% for negative tests. When P170 and P110 were both positive or negative, the CR rates were 27.3% and 81.8% respectively (p = 0.0120), and survival curves were also different (p = 0.030). The CR rate in AML or ALL is weakly affected by GST pi, alpha or mu but relapses are more frequently observed for Positive-GST pi ALL (p = 0.0658). Patients with both P170 and GST pi positive reactions had a 53.3% CR rate compared to 78.9% for both negative reactions. Survival curves for these two groups were different. The CR rate in AMl was 100% for Mts positive and 43.7% for negative cases (p = 0.050), however the median survival was totally different for these two groups (p = 0.046). CR rates were 26.6% for patients who were P170 positive and Mts negative compared to 100% for P170 negative and Mts positive (p = 0.038) patients. Survival curves were also different (p = 0.0510). We conclude that these four mechanisms induce an independent drug resistance but their synergic action increase their impact on the outcome. The metallothioneins seem to have a major impact on the drug resistance phenomenon and its effect should be investigated with high priority, in the light of these results.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

Altered neurofilament expression does not contribute to Lewy body formation.

Lewy bodies (LBs) are cytoskeletal alterations found in several neurodegenerative disorders. Although neurofilaments are the main constituent of the LB, the precise mechanisms that underlie their formation remain speculative. To examine the pathogenesis of this inclusion, we measured the mRNA level of the low molecular weight neurofilament subunit in the nigral dopaminergic neurons of patients with LB disorders and neurologically normal controls. We found a small but significant decrease in the mean mRNA values in the LB group as compared with controls. However, a comparison of LB-bearing and non-LB-bearing neurons on the same section showed no significant difference between these two neuronal populations. We conclude that altered neurofilament expression is not a major contributory event in the pathogenesis of the LB. The decrease in neurofilament mRNA expression observed in the overall nigral dopaminergic neuronal population of LB disorders probably represents a nonspecific response to neuronal injury independent of LB formation.

Aged↗
PubMed1996

Copper/zinc superoxide dismutase expression in the human central nervous system. Correlation with selective neuronal vulnerability.

Oxidative stress has been implicated in the pathogenesis of several neurological disorders. We examined the regional distribution of copper/zinc superoxide dismutase (SOD-1), one of the key antioxidant enzymes, in the human central nervous system using in situ hybridization. Our results show that the enzyme is present at high levels of constitutive expression in alpha-motor neurons, oculomotor neurons, nucleus basalis, substantia nigra, neocortex, and the hippocampal sector resistant to hypoxia (H2). Relatively lower levels were found in Sommer's sector (H1) and Purkinje cells. We conclude that a lower constitutive level of SOD-1 expression may play a role in the selective vulnerability of certain neuronal populations to hypoxia but does not correlate with the patterns of neurodegeneration observed in amyotrophic lateral sclerosis. Parkinson's disease, and Alzheimer's disease.

Adult↗
PubMed1996

Allogeneic bone marrow transplantation vs aggressive post-remission chemotherapy for children with acute myeloid leukemia in first complete remission. A prospective study from the French Society of Pediatric Hematology and Immunology (SHIP).

The objective of this study was to compare allogeneic bone marrow transplantation (BMT) with high-dose cytarabine containing chemotherapy in children with acute myeloid leukemia (AML) in first complete remission (CR). One hundred and seventy-one children were enrolled on the LAME89/91 protocol. Induction chemotherapy was a combination of cytarabine and mitoxantrone. After achieving CR, patients who had an HLA-identical sibling donor underwent allogeneic BMT. Children not eligible for BMT received post remission chemotherapy which included two consolidation courses, the second consolidation consisting of high-dose cytarabine with amsacrine and asparaginase. CR was achieved in 149 children (87%). Thirty-two had an HLA-identical sibling donor and were eligible for BMT. These 32 patients, as well as an additional child who had a one antigen HLA-mismatched father, received BMT during first CR. Consequently, 33 patients were analyzed in the BMT group and 116 in the chemotherapy group. The 4-year probability of relapse was 26 +/- 15% in the BMT group and 47 +/- 10% in the chemotherapy group (P = 0.04). The risk of therapy-related death was 3% for BMT and 7.7% for chemotherapy. Disease-free survival (DFS) was 72 +/- 15% in the BMT group and 48 +/- 10% in the chemotherapy group (p = 0.02). We conclude that allogeneic BMT from a matched sibling donor is the treatment of choice for reducing the relapse risk and for increasing DFS in children with AML in first CR.

Amsacrine↗
PubMed1996

[Precancerous and cancerous involvement of the uterine cervix. Results of a survey conducted by the "Genital Cancers" group of Ile-de-France, May 1990-May 1992, based on 8,805 biopsies].

Results of a study conducted by the "cervix cancer group" of PETRI, in Ile-de-France, from May 1990 to May 1992, and based on 8,805 biopsy specimens. In the absence of Cancer Registry in the Ile de France, no reliable data on invasive and preinvasive neoplasia of the cervix are available concerning this area. The aim of this survey, performed between May 15th, 1990 and May 15th, 1992 in 62 laboratories of pathology under the aegis of the Petri Association (Prévention et épidémiologie des tumeurs en Ile-de-France), was to obtain a better knowledge of this pathology, in which one of the major risk factors is the infection of the cervical epithelium by specific types of human papillomavirus. Over the course of these two years, 8,805 biopsy specimens, taken from neoplastic lesions of the cervix, were analyzed. Intra epithelial neoplasia represented more than 90% of the registered lesions. The average age at the time of the diagnosis was 32.4 years for the cases of condyloma, 32.7 years for CIN I, 33.8 years for CIN II, 36.3 years for CIN III, 45.7 years for micro-infiltrative carcinoma and 50.8 years for infiltrative squamous cell carcinoma. The breakdown of the different histological types of lesions is presented for three characteristic age groups (20-25, 30-35, and 60-70 years old). Differences observed in the eight departments belonging to the Ile-de-France are discussed.

Adult↗
PubMed1996

[Massive allografts of the pelvis. Possibilities and limitations in oncologic and reconstructive surgery].

Nine massive hemipelvic allografts were used to reconstruct the pelvic ring and the hip articulation after resection of malignant tumors. At follow up of 3 to 10 years, six patients were free of oncologic disease. In the 3 acetabular massive allografts, functional results were close from those standard THR. After resection of hemipelvis and adjacent muscles, patients resume a normal family life (painless hip, poor active motion, walking with a crutch) with a functional result much better than after amputation. Considering these encouraging results in oncologic surgery, we used similar technics for reconstruction of very severe bone loss after iterative failures of THR revisions: some examples are reported at medium follow up.

Adolescent↗
PubMed1995

Polymerase chain reaction quantification of lymphoid amyloid precursor protein mRNAs in Alzheimer's disease and Down's syndrome.

Amyloid beta-protein, the major constituent of Alzheimer's disease (AD) brain amyloid deposits, is encoded by several alternatively spliced amyloid precursor protein (APP) mRNAs. The well-established associated in Down's syndrome (DS) between APP overproduction and premature development of AD, as well as the recent demonstration of an increase in APP transcripts from lymphoblastoid cells of familial AD cases, suggest aberrant transcriptional regulation of some genes in AD. We assayed steady-state expression of the APP gene transcripts in peripheral blood mononuclear cells (PBMC) of AD and DS patients using quantitative polymerase chain reaction of reverse-transcribed mRNAs, and we compared their levels of PBMC APP expression with those of young and age-matched healthy controls. Results indicate APP mRNAs were of comparable abundance in PBMC obtained from 9 AD patients, 7 young controls and 12 age-matched controls. These data suggest regulation of APP mRNAs is normal in AD and DS PBMC.

Adult↗
PubMed1995

Alzheimer paired helical filaments: a comparison with the twisted ribbon model.

To investigate if Alzheimer paired helical filaments (PHF) closely resemble twisted ribbons, as indicated by recent high-resolution ultrastructural studies, we compared physical models of twisted ribbons with electron microscopic images of PHF. Uranyl-acetate-stained, isolated PHF with one or two helical turns were compared with scale models of twisted ribbons with one and two helical turns rotated at different angles. The various rotations of the twisted ribbon model corresponded well with the different orientations of randomly dispersed PHF. The electron-dense regions of individual PHF turns previously thought to represent a cross-over site of paired filaments corresponded to the edge of the twisted ribbon when the ribbon was oriented perpendicular to the filament axis. These data indicate that the overall configuration of PHF is a twisted ribbon but does not exclude possible configuration restrictions due to an ordered arrangement of subunits.

Alzheimer Disease↗
PubMed1995

Oxidative stress: its role in the pathogenesis of amyotrophic lateral sclerosis.

The discovery of mutations in the Cu,Zn superoxide dismutase gene in familial ALS implicates oxidative stress in the pathogenesis of this disorder. Recent findings further suggest that oxidative stress may also be present in the more common sporadic form of the disease. The possible sources of oxidative stress in ALS are reviewed, and the participation of this disease mechanism to motorneuron death is discussed.

Amyotrophic Lateral Sclerosis↗
PubMed1995

Papanicolaou smears in human immunodeficiency virus-seropositive women during follow-up.

OBJECTIVE: To assess the outcome of cervical squamous intraepithelial lesions (SIL) in human immunodeficiency virus (HIV)-seropositive women. METHODS: Papanicolaou smears were followed-up prospectively in a group of 60 HIV-positive women every 6 months for 18 months. RESULTS: The cumulative incidence of SIL at 18 months was 9% in 27 women who presented with normal Papanicolaou smears at entry. In 33 women who initially presented with SIL, the rate of persistence of cervical lesions was 95% (18 of 19) in untreated patients and 61% (eight of 13) in women who underwent surgery. In women with low-grade SIL, the persistence or progression of cervical lesions was observed in 92% of the cases (12 of 13). No invasive cancer was observed during the 18 months of the study period. CONCLUSION: Although the long-term outcome of SIL in this population remains unknown, our results emphasize the high rate of persistence of SIL and the relative inefficiency of conventional treatment in HIV-infected women. These findings contrast with the natural history of SIL in immunocompetent women.

Adult↗
PubMed1995

CD34+ cell immunoselection from G-CSF-alone-primed peripheral blood in children with low body mass.

We report the data of CD34+ cell immunoselection from peripheral blood after G-CSF-alone mobilization (10 micrograms/kg/d s.c.) in nine children with neuroblastoma (median age 4-5 years (2-8), median body weight 16 kg (10-20). Leukaphereses were carried out on a Cobe Spectra separator and two consecutive harvests (4 blood volumes processed) were used for immunoselection on a Ceprate column. The yield of CD34+ cells in the purified fraction was 50% (23-80), with a median number of 2.8 x 10(6) CD34+ cells/kg (1-9.4). All patients were reinfused with selected CD34+ cells after busulfan 600 mg/m2 +melphalan 180 mg/m2 and achieved successful haemopoietic recovery.

Antigens, CD34↗
PubMed1995

Erythrocyte polyamine levels: an indication of successful engraftment of bone marrow in children.

We studied the evolution of erythrocyte polyamine levels after 17 autologous bone marrow transplants (BMT) in 16 children with malignant diseases. We found that the time to the end of aplasia (0.5 x 10(9) granulocytes per liter) could be divided into 2 distinct periods. The first is characterized by low erythrocyte spermidine (Spd) and spermine (Spm) levels; the second is characterized by normal levels of polyamines. Spd and Spm levels were correlated (r = 0.74) during the second period, but not during the first period or in the control group. Furthermore, the time when Spd concentration was > or = 7 nmol/8 x 10(9) erythrocytes (19 +/- 7) was correlated (r = 0.64) with the advent of end of aplasia (30 +/- 10). We found no correlation between the numbers of CFU-GM and duration of aplasia levels or the duration of period A. The establishment of normal erythrocyte spermidine levels is the earliest index of successful marrow engraftment.

Adolescent↗