PubMed Health⌕ Search

Biomedical subjects

F Berger

Publications and source records attributed to F Berger.

At least 253 records · Page 14Linked to original sources
PubMed1994

Activation of a potassium outward current by zymosan and opsonized zymosan in mouse peritoneal macrophages.

The effects of zymosan and human serum opsonized zymosan on membrane currents of adherent mouse peritoneal macrophages which had been cultured for 5 to 20 days were investigated with the whole-cell voltage-clamp technique. Both stimuli activated an outward current. The outward current activation was transient and lasted about 5 min. In solutions with 10 or 50 mmol/l extracellular potassium concentration the activation of an outwardly directed current occurred at test potentials positive to the respective potassium equilibrium potential. This particle-induced current resembled a calcium-activated potassium current which could be activated with the calcium ionophore A 23187 and with platelet activating factor. The order of maximal responses (test potential + 55 mV, amplitude given as percentage of the respective control) was: 0.1 mumol/l platelet activating factor (222 +/- 36%, n = 8, P < 0.01) > 1 mumol/l A 23187 (190 +/- 24%, n = 11, P < 0.01) > 900 micrograms/ml opsonized zymosan (134 +/- 7%, n = 22, P < 0.01) > 900 micrograms/ml zymosan (116 +/- 5%, n = 21, P < 0.01). The lower efficiency of zymosan as compared to opsonized zymosan is explained in part by a lower percentage of responding cells which was 48% for zymosan and 73% for opsonized zymosan. Macrophages which were pretreated with particles showed a greater reactivity to calcium as compared to untreated cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Triple association: extramembranous glomerulonephritis, renal adenocarcinoma and splenic hamartoma. Apropos of a case].

We report the case of a 36 year old woman who presented a renal cell carcinoma, associated to a membranous nephropathy as a paraneoplastic syndrome. The concomitant association with a splenic hamartoma was probably fortuitous. Five years after nephrectomy, the patient was asymptomatic and her proteinuria was very low. We studied in the literature 93 cases which reported a such association between cancer, nephrotic syndrome and membranous nephropathy. Carcinoma of the lung and adenocarcinoma of the gastrointestinal tract are the most frequently implicated. This association can occur at every age and more often in men (75%) than in women. The survival is directly linked to the evolution of the cancer. Proteinuria and membranous nephropathy can totally disappear after surgical resection of the carcinoma. The glomerular injury is mediated by immune complexes composed at least in part of tumour associated antigens. The development of several types of glomerular injury in patients with carcinoma have been described but membranous glomerulonephritis is the most commonly observed.

Adenocarcinoma↗
PubMed1994

Heterogeneity of neoplastic and reactive cell proliferation in non-Hodgkin's lymphomas linked to patient survival.

This study was undertaken to determine the characteristics of the proliferation of malignant and reactive cells in non-Hodgkin's lymphoma (NHL). Cell kinetics were studied in 76 previously untreated cases of NHL by flow cytometry after a double labeling of membrane antigen and DNA. Results were analyzed according to clinical and biologic characteristics of the patients. In B-cell NHL, percentages of B and T cells in S-phase were strongly linked (r = .82). The level of proliferation of malignant B cells and reactive T cells was significantly higher in aggressive lymphomas, compared with low grade, diffuse small cleaved cell NHL or reactive lymph nodes (P < .001). The percentages of malignant B cells in S-phase were lower when reactive T cells were more numerous (n = 59, r = -.264, P < .05), particularly in high-grade NHL (n = 16, r = -.78, P < .001). In the whole population of patients, survival was longer when the percentage of cells in S-phase (n1 = 38, n2 = 33) or S+G2 + mitosis (M) (n1 = 36, n2 = 35) was less than 3.2% and 7.25%, respectively (P < .005). When considering only B-cell NHL, survival was longer when the percentage of B cells in S-phase was less than 4.5% (n1 = 31, n2 = 28, P < .04). Among the slowly proliferative groups of lymphomas, this prognostic value was retained when S-phase value was less than 1% (n1 = 16, n2 = 13, P < .002). Furthermore, prognosis was better when the percentage of T cells in S-phase was less than 2.75% (n1 = 30, n2 = 29, P < .01) or when reactive CD4-positive T cells were more than 14.5% (n1 = 24, n2 = 24, P < .04). This result remained true in the group of highly proliferative lymphomas. These results illustrate the complexity of the interactions between malignant and reactive cells in NHL, with possible opposite effects on tumor cell growth.

Adolescent↗
PubMed1994

Improvement in left ventricular dysfunction after aortic reimplantation in 11 consecutive paediatric patients with anomalous origin of the left coronary artery from the pulmonary artery. Early results of a serial echocardiographic follow-up.

To study the potential for recovery of left ventricular function in patients with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) after aortic reimplantation, serial two-dimensional echocardiographic examinations were performed before and up to 9 months after operation in 11 consecutive paediatric patients (group 1: six infants; group 2: five children above the age of 1 year). End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), myocardial volume (MV), ratio of myocardial volume/end-diastolic volume (MVI), and regional wall motion of the left ventricle (LV) were studied. Pre-operatively, mean LVEDV was 339% of normal in group 1 and 289% in group 2 (P < 0.001); mean LVMV was about twice the normal value in both groups (P < 0.001); LVMVI was 0.79 +/- 0.23 in group 1 and 0.83 +/- 0.3 in group 2; LVEF was 28 +/- 10% in group 1 and 46 +/- 18% in group 2; regional wall motion was normal in two group 2 patients, the other showed uniform reduction in segmental shortening fraction. Postoperatively, mean LVEDV tended to become normal after 2 weeks in group 1 and after 3 months in group 2. In both groups mean LVEF reached the normal range after 3 months; LVMV as well as LVMVI normalized after 9 months. Three months after the operation, all infants had a nearly normal pattern of regional wall motion, while in three group 2 children a residual reduced shortening fraction could be observed in anterior or lateral segments.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta, Thoracic↗
PubMed1994

[13C-urea breath test for the diagnosis of Helicobacter pylori infection. Comparison with histology].

OBJECTIVE: This study was to evaluate the 13C-urea breath test for the diagnosis of Helicobacter pylori infection compared with pathological data of gastric antrum and fundus endoscopic biopsies. METHODS: In 95 patients, the results of the 13C-urea breath test were retrospectivally compared with histology (standard and Giemsa staining). RESULTS: Using a ROC curve, the best cut-off value for the 13C-urea breath test was determined at + 3 delta 0/00 of breath isotopic enrichment. Compared with histology, the diagnostic values of the 13C-urea breath test were: sensibility 90.3%, specificity 97%, positive predictive value 98.2%, negative predictive value 84%. The false negative results of the breath test (6 out of 95) were obtained in patients with few H. pylori present in antral biopsies, or in patients under omeprazole therapy. The urea breath test was well correlated with the inflammation of the gastric mucosa (P < 0.0001). The isotopic enrichment in breath was well correlated to the number of H. pylori estimated by histological analysis (P < 0.05). CONCLUSIONS: The 13C-urea breath test is a non invasive and non radioactive diagnostic tool for H. pylori infection. Its excellent positive predictive value and its good negative predictive value guarantee its usefulness in clinical practice, especially for the control of eradication after anti-H. pylori therapy.

Biopsy↗
PubMed1994

Anomalous origin of the left coronary artery from the pulmonary artery. Early results with direct aortic reimplantation.

Between January 1991 and June 1993, eleven children with anomalous origin of the left coronary artery from the pulmonary artery underwent direct aortic reimplantation of the left coronary artery at the German Heart Institute Berlin. The patients' ages ranged from 2.5 months to 10.5 years; six were infants. Three infants were intubated and their lungs ventilated before the operation, and one was resuscitated 2 days before the operation. The electrocardiograms of eight patients indicated deep Q waves. All but three of these patients had insufficient collaterals between the right and left coronary arteries. The entire group exhibited reduced left ventricular ejection fraction (minimum 15%) including mitral valve incompetence, which was moderate in six patients and severe in three. All six infants underwent emergency operations, and the remaining children, who were older, underwent elective operations involving moderate hypothermic perfusion and cold crystalloid cardioplegia. Aortic cross-clamping time ranged from 22 to 79 minutes (mean 54 minutes). A two-coronary artery system was established in all patients by direct reimplantation of the anomalous left coronary artery into the ascending aorta. Three patients who also exhibited severe mitral valve incompetence underwent modified Kay mitral valve annuloplasty. A delayed sternal closure procedure (closure performed 1 to 10 days after the operation) was used on eight patients. A 10-month-old patient was successfully treated after the operation with a centrifugal left heart assist device and a 9-year-old patient received extracorporeal membrane oxygenation because of severe heart failure. No postoperative deaths occurred. Left ventricular end-diastolic volume decreased dramatically after the operation and returned to near normal values 1 to 9 months postoperatively. At the same time, the preoperatively depressed left ventricular ejection fraction returned to normal and mitral valve incompetence decreased or vanished in eight patients. Color Doppler echocardiograms (eleven patients) and coronary angiograms (three patients) indicated that the reimplanted left coronary artery was patent in all eleven patients during the follow-up period. Reimplantation of the left coronary artery into the ascending aorta is an effective method of establishing a two-coronary artery system in children with anomalous origin of the left coronary artery from the pulmonary artery. Mitral valve annuloplasty is recommended for patients who also have severe mitral valve incompetence. Prolonged assisted circulation must be used in cases of severe postoperative heart failure.

Aorta↗
PubMed1993

Five-year survival after transhiatal resection of esophageal carcinoid tumor with a lymph node metastasis.

BACKGROUND: Carcinoid tumors of the esophagus are rare. Most reported cases have had a poor prognosis. The authors report the case of a 64-year-old man with a 4-cm carcinoid tumor of the lower esophagus. METHODS: Following endoscopic resection of an argyrophilic, nonargentaffin, carcinoid tumor of the lower esophagus, endosonography showed residual tumor, suggestive of a metastatic lymph node. The findings were confirmed at transhiatal esophagectomy. RESULTS: No recurrence has been observed along the current 5-year follow-up. CONCLUSIONS: Lymph node metastasis does not rule out the possibility of prolonged survival in esophageal carcinoids. Endosonography is strongly advisable for preoperative evaluation.

Carcinoid Tumor↗
PubMed1993

[Lymphomas in immunocompromised hosts].

Congenital and acquired states of immunodeficiency are associated with an increased incidence of ill-defined lymphoproliferations. These are mainly B-cell, often extranodal, lymphoproliferations commonly associated with EBV. Their incidence is increasing with the rapid development of organ transplantation and spreading of the HIV infection. The association with EBV partly explains the pathogeny of these affections. This ubiquitous virus immortalizes B lymphocytes in vitro and is tumorigenic for new world primates. An EBV-specific cytotoxic T-cell memory prevents uncontrolled proliferation of infected B cells in normal subjects after the primary infection. The X-linked lymphoproliferative syndrome is a primary immunodeficiency characterized by an abnormal immune responsiveness to EBV, resulting in fatal infectious mononucleosis and malignant lymphoma. The severe immunosuppression present in transplanted patients allows EBV infected cells to proliferate, giving rise to a spectrum of lymphoproliferations. Reduction of immunosuppression alone is, in some cases, sufficient to produce tumor regression. The evolution of these affections is difficult to predict and requires a combined biological and clinical analysis, in order to evaluate the aggressivity of the tumor and the ability of the immune response of the host. HIV infected patients have an increased risk of developing Burkitt's lymphomas which are associated with EBV in 50% of the cases. Patients with AIDS at an advanced stage, present immunoblastic large cell lymphomas associated with EBV, similar to the post-transplant lymphomas. Lymphoproliferations in immunodeficiencies constitute a model for evaluation of the interaction between EBV and the immune system.

Animals↗
PubMed1993

Rearrangement and overexpression of the BCL-1/PRAD-1 gene in intermediate lymphocytic lymphomas and in t(11q13)-bearing leukemias.

The t(11;14)(q13;q32) translocation and its molecular counterpart, BCL-1 rearrangement, are consistent features of intermediate lymphocytic lymphoma (ILL). Rearrangement is thought to deregulate the nearby PRAD-1/BCL-1 proto-oncogene that is a newly identified member of the cyclin family. To characterize further the association between rearrangement of chromosome 11q13 and over-expression of BCL-1. Southern blot analysis was performed in 33 cases of ILL, 5 cases of t(11;14)-associated leukemias, and 1 case of leukemia carrying a variant translocation t(11;19)(q13;q13) using three separate BCL-1 locus probes. When RNA was available, BCL-1 expression was assessed by Northern blot analysis. DNA from 19 of 33 ILL (57%) showed BCL-1 rearrangement, 16 involving the major translocation cluster (MTC) region and 3 involving a new breakpoint cluster located in the 5' flanking region of the BCL-1 gene. DNA from 3 of 6 t(11q13)-associated leukemias demonstrated a rearrangement involving the MTC. Northern blot analysis showed that BCL-1 was overexpressed in 14 of 15 ILL and in all leukemias analyzed (included the t(11;19) leukemia) relative to normal and malignant lymphoid tissues. These results constitute additional elements in favor of the role of BCL-1 in lymphoid neoplasia and allow us to speculate about its mechanisms of activation.

Aged↗
PubMed1993

Identification and characterization of an anti-tyrosine kinase factor in cystic gliomas.

In view of the frequent activation of the epidermal growth factor receptor (EGF-R) in gliomas and autocrine hypothesis, we searched for 'EGF-like' factor(s) in cystic fluids (CFs) associated with gliomas. Membranes of A431 cells, which overexpress EGF-R, were used to explore such activity in 20 CFs. In all cases CFs induced inhibition of EGF-R phosphorylation. Biochemical analysis revealed an anti-tyrosine kinase activity which was identified as a 18 kDa proteic factor. Effectiveness at high dilution and anti-proliferative effect on living cells in culture suggest that this factor may be involved in the negative regulation of glial oncogenesis.

Astrocytoma↗
PubMed1993

FVT-1, a novel human transcription unit affected by variant translocation t(2;18)(p11;q21) of follicular lymphoma.

Variant t(2;18) and t(18;22) chromosome translocations observed in B-cell chronic lymphocytic leukemias and in follicular lymphomas have been reported to consistently involve the 5' region of the BCL-2 gene on chromosome 18 and various regions on the lg light chain loci. We show here that a variant t(2;18)(p11;q21) translocation observed in a case of follicular lymphoma leads to the juxtaposition of a J kappa segment to a chromosome 18 transcriptional unit located 10 kpb upstream of the BCL-2 locus. The cDNA of this new evolutionarily conserved gene, termed FVT-1 for follicular-variant-translocation gene, codes for a putatively secreted protein of 36 Kd that is not homologous with any described protein. The FVT-1 gene is weakly expressed in all the analyzed normal hematopoietic tissues but a very high rate of transcription is observed in some T-cell malignancies and in phytohemagglutinin-stimulated lymphocytes. The proximity of FVT-1 to the BCL-2 locus suggests that in the t(14;18) currently observed in follicular lymphomas, both genes would participate in the tumoral process.

Amino Acid Sequence↗
PubMed1993

Activation of membrane outward currents by human low density lipoprotein in mouse peritoneal macrophages.

The aim of the present study was to search for electrophysiological effects of human lipoproteins on membrane currents in mouse peritoneal macrophages which had been cultured for 5 to 20 days. Whole-cell currents were recorded by using a voltage-clamp technique. Low density lipoprotein (LDL, 100 micrograms/ml) increased a slowly activating nonspecific cation current (iso) in the positive potential range to 244 +/- 23% of the reference (test potential + 55 mV, n = 13, P < 0.005). Augmentation of current resulted out of a negative shift of the activation curve along the voltage axis (-22 mV) and an increase of maximally available current. Furthermore, LDL increased a rapidly activating outward current (ifo) at test potentials positive to the potassium equilibrium potential. At +55 mV ifo-amplitude increased to 165 +/- 14% of reference (n = 16, P < 0.005). LDL-induced effects on ifo-current could be mimicked by application of the calcium ionophore A 23,187 (1 mumol/l) which led to an increase of ifo-current to 161 +/- 25% of the reference (test potential +55 mV, n = 11, P < 0.005). Acetylated-LDL (100 micrograms/ml, 5-15 min) produced no significant effect on the membrane currents under investigation.

Animals↗
PubMed1993

A slowly inactivating transient outward current in rat ventricular myocytes.

In rat ventricular myocytes we found two components of transient outward current, which could be discriminated time- and voltage- dependently. Besides the well known fastly inactivating transient outward current (ito,f, tau = 35 +/- 8 ms, n = 4) we investigated properties of a slowly inactivating transient outward current (ito,s, tau = 1.7 +/- 0.4 s, n = 4). Because of the slow inactivation process of ito,s tail currents were observed at -25 mV. The inactivation curve of ito,f was characterized by a half- inactivation voltage of -58.4 +/- 1.4 mV and a slope factor of 5.6 +/- 0.5 mV (n = 4). The inactivation curves of ito,s and tail currents were nearly identical but significantly different from the ito,f-curve. Half-inactivation voltages of ito,s and tail currents were -87.5 +/- 6 mV and -89.1 +/- 5 mV (n = 4), respectively. Slope factors were 10.3 +/- 2.9 mV and 9.8 +/- 1.7 mV (n = 4). The activation gate of ito,s was half-maximally opened at -11.5 +/- 2.6 mV, and the slope factor was -10.6 +/- 1.7 mV (n = 3). Ito,s tail current reversed its direction at -62 +/- 3.2 mV (n = 5). This indicates, that ito,s- current flow is carried mainly by potassium ions. Ito,s- current was not abolished by Tetrodotoxin (TTX) and Cd.

Animals↗
PubMed1993

Characterization of normal brain-reactive antibodies in glioma cyst fluids.

Anti-normal brain antibodies were studied in glioma cyst fluids. Cyst fluids were obtained by stereotaxic puncture from 34 patients with cystic gliomas. Immunoglobulins were analyzed by immunohistochemistry, immuno-Western blotting, concentration measures, and isoelectrofocalization. 80% of cyst fluids stained astrocytes and/or microvessels in non-tumoral white matter. In white matter extracts, cyst fluids recognized five immunoreactive bands having apparent molecular masses of 50-75 kDa. Although cyst proteins could be of systemic origin, isoelectrofocalization analysis suggests an additional local immune response. These antibody activities could be involved in certain peritumoral events such as brain edema.

Autoantibodies↗
PubMed1993

Mutagens, N-nitroso compounds and their precursors in gastric juice from patients with and without precancerous lesions of the stomach.

This study examined whether elevated risk of gastric cancer is associated with high levels of total N-nitroso compounds (NOC), their precursors and nitrosation-dependent genotoxins in gastric juice (GJ). An improved method for quantifying total NOC was used and genotoxicity was assayed in E. coli. Results from patients (n = 210) with or without precancerous lesions of the stomach and living in three areas with up to 8-fold variations in gastric cancer risk (U.K., France, Colombia) were compared. The level of nitrite (range < 1-472 mumol/l) was found to increase with the pH of GJ from the three countries and was dependent on country of collection. The levels of NOC (range: < or = 0.01-8.0 mumol/l) in GJ were not affected by stomach histology and country of collection. NOC levels increased linearly with nitrite concentrations, but the slope of the regression line was greater for acidic GJ (pH < or = 4). These data together suggest that chemical nitrosation contributes at least as much as other nitrosation pathways to the intragastric formation of NOC. Acid-catalysed nitrosation of GJ in vitro increased the NOC concentration (range: 7-1332 mumol/l) up to several 1000-fold but this increase was not predictive of gastric cancer risk either by country or by stomach histology. After acid-catalysed nitrosation, direct genotoxicity (SOS-inducing potency) was significantly higher in GJ with original pH > 4 and highest in samples from Colombia. The results (a) provide no support that intragastric total NOC levels are elevated in subjects with precancerous stomach lesions or living in a high risk area for stomach cancer; (b) confirm that a high nitrite level and elevated pH in GJ are strongly associated, the level of nitrite being associated with precancerous stomach conditions only in Colombia; (c) reveal the presence of precursor compounds in GJ, that after nitrosation yield direct mutagens that probably contain NOC and other substances. As their concentrations were significantly higher in achlorhydric subjects and highest in Colombian patients, these data together provide support for a role of intragastrically formed nitrite-derived direct mutagens in gastric cancer aetiology.

Adult↗