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F Berger

Publications and source records attributed to F Berger.

At least 91 records · Page 5Linked to original sources
PubMed2001

Cystic endocrine tumors of the pancreas: clinical, radiologic, and histopathologic features in 13 cases.

Cystic endocrine tumors of the pancreas are rare and raise difficult clinical problems. Our aims were to reevaluate the diagnostic and therapeutic strategy and to assess their histopathologic characteristics. Thirteen cystic endocrine tumors diagnosed in 10 patients were included. Clinical, radiologic, and pathologic data were reviewed. There were 6 male and 4 female patients (median age, 46 yrs). Six patients had evidence of multiple endocrine neoplasia type 1 (MEN1) disease. Four had a functional endocrine syndrome. Ten tumors were visible on imaging studies. The most suggestive radiologic features were the existence of a peripheral hypervascular rim (10 cases) and images of cyst into cyst (two cases). On gross and histologic examinations, two distinct types were present. Macrocystic tumors (six cases) were unilocular and limited by a thick wall containing nests of tumor cells. Microcystic tumors (seven cases) were characterized by the presence of multiple cystic spaces directly lined by tumor cells. Surgical resection was performed in all cases. Three patients had lymph node metastases at the time of diagnosis. One patient is dead with metastatic dissemination. The others are alive without recurrence or metastasis. The diagnosis of endocrine tumor must be considered for any pancreatic cyst discovered in a patient with a history of MEN1 syndrome or with clinical features suggestive of this syndrome. Cystic pancreatic endocrine tumors must be treated by surgical resection because of their possible malignant evolution.

Adult↗
PubMed2001

Dynamic analyses of the expression of the HISTONE::YFP fusion protein in arabidopsis show that syncytial endosperm is divided in mitotic domains.

During early seed development, nuclear divisions in the endosperm are not followed by cell division, leading to the development of a syncytium. The simple organization of the Arabidopsis endosperm provides a model in which to study the regulation of the cell cycle in relation to development. To monitor nuclear divisions, we constructed a HISTONE 2B::YELLOW FLUORESCENT PROTEIN gene fusion (H2B::YFP). To validate its use as a vital marker for chromatin in plants, H2B::YFP was expressed constitutively in Arabidopsis. This enabled the observation of mitoses in living root meristems. H2B::YFP was expressed specifically in Arabidopsis syncytial endosperm by using GAL4 transactivation. Monitoring mitotic activity in living syncytial endosperm showed that the syncytium was organized into three domains in which nuclei divide simultaneously with a specific time course. Each mitotic domain has a distinct spatiotemporal pattern of mitotic CYCLIN B1;1 accumulation. The polar spatial organization of the three mitotic domains suggests interactions between developmental mechanisms and the regulation of the cell cycle.

Arabidopsis↗
PubMed2001

Percutaneous closure of large atrial septal defects with the Amplatzer Septal Occluder: technical overkill or recommendable alternative treatment?

To judge whether an Amplatzer Septal Occluder (ASO) can be used as a safe therapy instead of surgery for closure of large atrial septal defects > 25 mm in diameter, we report our experiences in 45 patients out of a cohort of 467 patients after successful ASO implantation within a period of 3 years. Median defect diameter was 28 mm (range 25-36), median age was 41.2 years (range 10.1-77.7 years). Body weight ranged from 33.5 to 112.0 kg (median 68 kg). Due to an inevitable reduction of the stent size with increasing distances of the discs fixed at the thicker part of the atrial septum in larger defects, we implanted devices 2-4 mm larger than the measured stretched diameter. Fluoroscopy times ranged from 2.0 to 24.4 minutes, with a median of 10.3 minutes. Follow-up studies were obtained after 48 hours and 1, 6, and 12 months, and then yearly. The median period of follow-up was 0.82 years (range 0.1-2.6). The complete occlusion rate was 91.1%. A trivial hemodynamically insignificant residual shunt remained in 8.9% of the patients. Three patients showed transient atrial tachyarrhythmias within the first 3 months after implantation and three remained in chronic atrial fibrillation. The excellent results in the short and medium term make Amplatzer device implantation a recommendable safe and effective alternative to surgery, even in selected cases with defects > 25 mm. Final judgement, however, is only possible after long-term follow-up.

Adolescent↗
PubMed2001

Echocardiographically guided closure of a patent foramen ovale during pregnancy after recurrent strokes.

BACKGROUND: Stroke during pregnancy and puerperium is a severe complication that causes high morbidity and mortality. A patent foramen ovale (PFO) allowing paradoxical embolism is one identified risk factor. CASE: A 25-year-old pregnant woman with PFO suffered from recurrent cerebral embolism. To prevent recurrent cerebral embolism during pregnancy, delivery, and puerperium, interventional closure of the PFO was performed without fluoroscopy under echocardiographic guidance. The postinterventional course was uneventful. CONCLUSION: Percutaneous transvenous closure of a PFO during pregnancy is feasible without the use of fluoroscopy.

Adult↗
PubMed2001

Microarray RNA quantification assay for large-scale nanosamples analysis.

We have developed a convenient and sensitive method for the quantification of RNA in samples from microbiopsies. This procedure is especially suitable for quantitating very small amounts of RNA in large-scale biological samples. This method, using a microarray-spotting facility for the study of multigenic expression, entails the hybridization of a DNA probe with RNA spotted at high density on nylon membrane. Furthermore, with this procedure, the reproducibility, sensitivity, and accuracy of the assay are notably improved as compared to current methods.

Biotechnology↗
PubMed2001

Chemical pathology in brain white matter of recently detoxified alcoholics: a 1H magnetic resonance spectroscopy investigation of alcohol-associated frontal lobe injury.

BACKGROUND: Investigations have suggested that frontal lobe abnormalities are a prominent feature of the alcoholic brain, indicated by impaired neuropsychological performance on tests of frontal lobe function and by reduced frontal lobe volume in neuroimaging and neuropathological examinations. White matter compartment volume loss may underlie observed brain shrinkage and cognitive deficits associated with the frontal lobes, although the nature of this change has not been well-characterized. METHOD: To investigate the susceptibility of frontal lobe white matter to alcohol-associated metabolic change and to understand the nature of alcohol-related white matter injury, 1H magnetic resonance spectroscopy (MRS) was used to measure concentrations of metabolites in frontal white matter (FWM) and parietal white matter (PWM) of recently detoxified alcoholics (RDA) and nonalcoholic controls (CON). Concentrations of N-acetylaspartate (NAA), choline-containing compounds (Cho), myo-inositol (Ins), and creatine plus phosphocreatine (Cr) were measured in 37 RDA (mean age, 40.4 years; mean length of abstinence, 27.9 days) and 15 CON (mean age, 38.0 years). RESULTS: Analysis of variance (ANOVA) revealed a group by region of interest interaction for concentrations of NAA. Simple effects analysis revealed a significant 14.7% reduction in FWM NAA, while NAA levels in PWM were similar in RDA and CON. In addition, RDA had an 11.8% increase (averaged across both regions of interest) in brain white matter Ins relative to CON. Reductions in FWM NAA were associated with a longer drinking history in the RDA group, but this result was not found when both age and drinking history were used to predict the level of FWM NAA. CONCLUSIONS: Alcohol-associated reductions in FWM NAA may be the result of neuronal loss or dysfunction in the metabolism of NAA. While alcohol-induced oxidative stress may cause global brain impairments in the metabolism and subsequent reduction of NAA, the frontal lobes are particularly rich in excitatory amino acid pathways, and axonal damage or destruction secondary to glutamate-mediated excitotoxicity during alcohol withdrawal may cause frontal lobe-specific reductions in NAA. Elevations in brain white matter Ins may reflect astrocyte proliferation as well as an osmotic response to cell shrinkage.

Adult↗
PubMed2001

[Hepatobiliary cystic tumors. Clinical, radiological and histopathological study of 7 cases].

OBJECTIVES: Hepatobiliary cystic tumors are rare, but must be correctly diagnosed because of their potential malignancy. We report the clinical, radiological, pathological and evolutive characteristics of 7 cases of hepatobiliary cystic tumors. MATERIAL AND METHODS: Complete clinical charts were available. Radiological and pathological documents were reviewed. RESULTS: There were 4 females and 3 males (median age, 58.7 yrs). In 3 cases, the presenting symptom was the palpation of a mass in the right upper abdominal quadrant. In 6 cases, pre-operative imaging studies showed a cystic intra-hepatic mass, containing vegetations and/or septa in 5 cases. In the remaining case, the radiological appearance showed a heterogeneous liver mass. Two patients were treated by pericystectomy and 5 by radical hepatectomy. At macroscopic examination, tumors were usually large (range: 2-24 cm) and multilocular. Histological diagnosis was: cystadenoma with mesenchymous stroma (2 cases), mucinous cystadenoma (2 cases), mucinous cystadenocarcinoma (2 cases), giant cell cystadenocarcinoma (1 case). The mean duration of follow up was 60 months. Two patients, both with cystadenocarcinomas, died after respectively, 21 and 34 months with metastatic dissemination. Five patients are alive without evidence of disease after a delay ranging from 14 to 144 months. CONCLUSION: Radical surgical treatment of cystic hepatobiliary tumors is necessary to obtain histopathological examination of the complete specimen, which is essential for a correct evaluation of the malignant potential of the lesion, and for prolonged survival, even in cases of locally invasive tumors.

Adult↗
PubMed2001

[Hemodynamic tolerance and rapid hypertrophy of a hepatic graft corresponding to less than 30% of the ideal mass in pigs].

BACKGROUND AND OBJECTIVE: Evaluation of a new pig liver transplantation technique for survival and hypertrophy of a small-sized graft by providing adapted and controlled venous portal flow. MATERIAL AND METHODS: [corrected] Twenty Large-White pigs underwent heterotopic liver transplantation after a mesocaval shunt and ligation of the superior mesenteric vein downstream from the shunt. The donor-to-recipient weight ratio was below 30%. Furthermore, recipient's biliary duct and portal vein into the hilum were tied. In a control group, no mesocaval shunt was performed and the graft received the entire splanchnic venous flow. RESULTS: The mesocaval shunt provided diversion of 60% of the splanchnic blood flow. The median survival of study pigs was 39 days (range: 8-98). Median serum bilirubin levels at 1 week were 12 micromol/L (range: 4-59). At autopsy, graft weight was increased to 2.7 times the initial weight and histological findings were normal. In the control group, all pigs died quickly from acute splanchnic congestion. CONCLUSION: In a model of heterotopic liver transplantation using small-sized grafts, complete diversion of mesenteric blood flow through a mesocaval shunt resulted in hemodynamic tolerance and hypertrophy of a graft corresponding to less than 30% of the ideal mass.

Anastomosis, Surgical↗
PubMed2000

Recent advances in imaging endogenous or transferred gene expression utilizing radionuclide technologies in living subjects: applications to breast cancer.

A variety of imaging technologies is being investigated as tools for studying gene expression in living subjects. Two technologies that use radiolabeled isotopes are single photon emission computed tomography (SPECT) and positron emission tomography (PET). A relatively high sensitivity, a full quantitative tomographic capability, and the ability to extend small animal imaging assays directly into human applications characterize radionuclide approaches. Various radiolabeled probes (tracers) can be synthesized to target specific molecules present in breast cancer cells. These include antibodies or ligands to target cell surface receptors, substrates for intracellular enzymes, antisense oligodeoxynucleotide probes for targeting mRNA, probes for targeting intracellular receptors, and probes for genes transferred into the cell. We briefly discuss each of these imaging approaches and focus in detail on imaging reporter genes. In a PET reporter gene system for in vivo reporter gene imaging, the protein products of the reporter genes sequester positron emitting reporter probes. PET subsequently measures the PET reporter gene dependent sequestration of the PET reporter probe in living animals. We describe and review reporter gene approaches using the herpes simplex type 1 virus thymidine kinase and the dopamine type 2 receptor genes. Application of the reporter gene approach to animal models for breast cancer is discussed. Prospects for future applications of the transgene imaging technology in human gene therapy are also discussed. Both SPECT and PET provide unique opportunities to study animal models of breast cancer with direct application to human imaging. Continued development of new technology, probes and assays should help in the better understanding of basic breast cancer biology and in the improved management of breast cancer patients.

Animals↗
PubMed2000

Antibodies to endostatin in a multifocal glioblastoma patient.

Endostatin, a C-terminal fragment of collagen XVIII is involved in the regulation of neovascularisation in solid tumours in mice. However, few data are available on the concentration of endostatin protein in patients with cancer. Paradoxical results obtained in this way prompted us to investigate an antibody to endostatin. We detected antibodies to endostatin in the serum and in the tumour brain tissue of a patient with a multifocal glioblastoma, and in the serum samples from two patients with aggressive tumours. These data suggest that endostatin overexpression by tumour tissue might induce a humoral immune response.

Angiogenesis Inhibitors↗
PubMed2000

Bacterial DNA methylation and gene transfer efficiency.

The necessary amplification step in bacteria of any plasmid currently used in DNA immunization or gene therapy introduces modification in the nucleotide sequence of plasmid DNA used in gene transfer. These changes affect the adenine and the internal cytosine in respectively all of the GATC and CC(A/T)GG sequences. These modifications which introduce 6-methyladenine and 5-methylcytosine in plasmidic DNA are the consequence of the existence of the bacterial modification systems Dam and Dcm. In eucaryotes, the presence of 5-methylcytosine at dinucleotides -CG- is involved in silencing gene expression, but the possible consequences of the presence of the bacterial G(m)ATC and C(m)C(A/T)GG sequences in the plasmids used in gene transfer experiments are presently unknown. Since the possibility exists to obtain plasmid DNA lacking this specific bacterial pattern of methylation by using (dam(-), dcm(-)) bacteria we performed experiments to compare in vitro and in vivo gene transfer efficiency of a pCMV-luc reporter plasmid amplified either in the JM109 (dam(+), dcm(+)) or JM110 (dam(-), dcm(-)) bacteria. Data obtained demonstrated that the presence of 6-methyladenine in GATC sequences and 5-methylcytosine in the second C of CC(A/T)GG motifs does not reduce the levels of luciferase activity detected following in vitro or in vivo gene transfer. On the contrary, gene transfer with a pCMV-luc amplified in JM109 (dam(+), dcm(+)) bacteria gives greater amounts of luciferase than the same transfection performed with a plasmid amplified in the mutated JM110 (dam(-), dcm(-)) counterpart. Therefore, these data do not suggest that the use of (dam(-), dcm(-)) bacteria to amplify plasmid DNA may increase gene transfer efficiency. However, the persistence of the use of (dam(+), dcm(+)) bacteria in order to amplify plasmid DNA raises the question of the possible biological consequences of the introduction of the bacterial G(m)ATC and C(m)C(A/T)GG sequences in eukaryotic cells or organisms.

5-Methylcytosine↗
PubMed2000

Muscle transfection by electroporation with high-voltage and short-pulse currents provides high-level and long-lasting gene expression.

Gene transfer into muscle by electroporation with low-voltage and long-pulse (LV/LP, 100 V/50 msec) currents was shown to be more efficient than simple intramuscular DNA injection. Nevertheless, transgene expression declined from day 7 and only reached 10% of the maximum 3 weeks after electroporation. We have optimized electroporation conditions including voltage, pulse number, and the amount of injected luciferase-encoding plasmid DNA in the tibialis anterior muscle. Using high-voltage and short-pulse (HV/SP, 900 V/100 microsec) currents, we observed an average 500-fold increase in luciferase expression, in comparison with nonelectroporated muscle. Moreover, sustained and long-lasting gene expression was observed for at least 6 months. When we compared HV/SP currents with LV/LP currents, luciferase expression was similar 24 hr after electroporation. One month later, whereas luciferase expression was stable in muscle electroporated with HV/SP currents, it decreased 600-fold in muscle electroporated with LV/LP currents. In conclusion, electroporation with high-voltage and short-pulse currents provides high-level and long-lasting gene expression in muscle.

Animals↗
PubMed2000

Comparison of chemotherapy to radiotherapy as consolidation of complete or good partial response after six cycles of chemotherapy for patients with advanced Hodgkin's disease: results of the groupe d'études des lymphomes de l'Adulte H89 trial.

The treatment of advanced Hodgkin's disease (HD) with chemotherapy (CTx) alone or combined modality treatments has been controversial. In 1989, we designed a randomized study to compare 2 cycles of CTx to (sub)total nodal irradiation (RTx) as consolidation treatments for patients with stage IIIB/IV HD in complete remission (CR) or good partial response after 6 cycles of CTx. A total of 559 patients were randomized to receive 6 cycles of MOPP/ABV (mechlorethamine, vincristine, procarbazine, prednisone/Adriamycin [doxorubicin], bleomycin, vinblastine) hybrid (n = 266) or ABVPP (n = 267). After induction treatment, 418 patients could be evaluated for the consolidation phase. With a median follow-up of 48 months, the 5-year disease-free survival estimates were 80% for 8 cycles of MOPP/ABV, 82% for 6 cycles of MOPP/ABV plus RTx, 68% for 8 cycles of ABVPP, and 75% for 6 cycles of ABVPP plus RTx (P =.01). The 5-year disease-free survival estimates did not differ between CTx and RTx, 74% and 79%, respectively (P =.07). After MOPP/ABV, the 5-year overall survival estimates did not differ between CTx and RTx, 85% and 88%, respectively (P =.2). After ABVPP, the 5-year survival estimates were 94% for CTx and 78% for RTx (P =.002). These results showed that RTx was not superior to CTx consolidation after doxorubicin-induced CR for patients with advanced HD. Because of the uncertainty of obtaining a prolonged second remission for patients relapsing after CTx and RTx and the possible long-term effects of RTx, we prefer 8 cycles of CTx as standard treatment when a CR has been achieved after 6 cycles.

Adolescent↗
PubMed2000

Non-MALT marginal zone B-cell lymphomas: a description of clinical presentation and outcome in 124 patients.

Marginal zone B-cell lymphoma (MZL) is a recently individualized lymphoma that encompasses mucosa-associated lymphoid tissue (MALT) lymphoma, splenic lymphoma with or without villous lymphocytes, and nodal lymphoma with or without monocytoid B-cells. If the clinical description and outcome of MALT lymphoma is well known, this is not the case for the other subtypes. We reviewed 124 patients presenting non-MALT MZL treated in our department to describe the morphologic and clinical presentation and the outcome of these lymphomas. Four clinical subtypes were observed: splenic, 59 patients; nodal, 37 patients; disseminated (splenic and nodal), 20 patients; and leukemic (not splenic nor nodal), 8 patients. These lymphomas were usually CD5-, CD10-, CD23-, and CD43-, but the detection of one or, rarely, two of these antigens may be observed. Bone marrow and blood infiltrations were frequent, except in the nodal subtype, but these locations were not associated with a poorer outcome. Splenic and leukemic subtypes were associated with a median time to progression (TTP) longer than 5 years, even in the absence of treatment or of complete response to therapy. Nodal and disseminated subtypes were associated with a median TTP of 1 year. However, in all these subtypes, survival was good with a median survival of 9 years, allowing these lymphomas to be classified as indolent. Because of the retrospective nature of this analysis, no conclusion may be drawn on the therapeutic aspects, but conservative treatments seem recommended for leukemic and splenic subtypes. (Blood. 2000;95:1950-1956)

Age Factors↗
PubMed2000

Transcatheter closure of atrial septal defects without fluoroscopy: feasibility of a new method.

BACKGROUND: In an effort to reduce x-ray exposure, we developed a technique for transcatheter closure of atrial septal defects under echocardiographic guidance without fluoroscopy. To assess the efficiency of this procedure for routine use, we compared our initial results with those for the conventional procedure. METHODS AND RESULTS: Twenty-two randomly selected patients (median age 18 years; range 2 to 66 years) with atrial septal defects (n=13) or patent foramen ovale (n=9) underwent cardiac catheterization for possible interventional defect closure with echocardiography as the only imaging tool. Median stretched diameter was 9 mm (range 6 to 26 mm); median left-to-right shunt over the atrial septal defects was Qp/Qs=1.8 (range 1.5 to 2.6). An Amplatzer septal occluder was successfully implanted in 19 defects without fluoroscopy and in 3 with the help of radiography. After 1 month, complete defect closure was documented in all patients. Compared with the conventional procedure of a control group of 131 patients, procedure times were not significantly different (88 versus 100 minutes; P=0.09). However, the study group received significantly higher doses of propofol for sedation (9.9 versus 5.6 mg/kg body weight; P=0.002) owing to extended transesophageal echocardiography. CONCLUSIONS: In the majority of patients in whom transcatheter closure of interatrial communications with the Amplatzer septal occluder is possible, the procedure can be safely performed under echocardiographic guidance without fluoroscopy.

Adolescent↗
PubMed2000

Mucosa-associated lymphoid tissue lymphoma is a disseminated disease in one third of 158 patients analyzed.

Mucosa-associated lymphoid tissue-derived lymphoma (MALT lymphoma) is usually a very indolent lymphoma, described as localized at diagnosis and remaining localized for a prolonged period; dissemination occurs only after a long course of evolution. In our database, out of 158 patients with MALT lymphoma, 54 patients presented with a disseminated disease at diagnosis. Of these 54 patients, 17 patients (30%) presented with multiple involved mucosal sites; 37 patients (70%) presented with 1 involved mucosal site, but in 23 of these patients (44%), dissemination of the disease was due to bone marrow involvement; 12 patients (22%) had multiple lymph node involvement; and 2 patients (4%) had nonmucosal site involvement. No significant difference in clinical characteristics (sex, age, performance status, B symptoms) and biological parameters (hemoglobin [Hb] and lactate dehydrogenase levels) was observed between localized or disseminated MALT-lymphoma patients. Only beta2-microglobulin level was significantly more elevated in disseminated disease patients than in localized disease patients. Complete response after the first treatment was achieved in 74% of the patients, and there was no difference between the 2 groups. With a median follow-up of 4 years, the estimated 5- and 10-year overall survival rates were similar in the 2 groups, 86% and 80%, respectively. The median freedom-from-progression survival was 5.6 years for all patients, surprisingly without any difference between localized and disseminated MALT-lymphoma patients. In conclusion, MALT lymphoma is an indolent disease but presents as a disseminated disease in one-third of the cases at diagnosis. The dissemination does not change the outcome of the patients.

Adult↗