PubMed Health⌕ Search

Biomedical subjects

F Bergmann

Publications and source records attributed to F Bergmann.

At least 37 records · Page 2Linked to original sources
PubMed1999

Severe protein C deficiency and aseptic osteonecrosis of the hip joint: a case report.

UNLABELLED: Homozygous congenital protein C deficiency is accompanied by severe thrombophilia. Thrombotic events can be reduced in number and severity by lifelong oral anticoagulation therapy. A 4-year-old boy was first diagnosed as having severe congenital homozygous protein C deficiency during the neonatal period when purpura fulminans occurred as the first manifestation of thrombosis. From this time he had been treated with phenprocoumon (INR 3.5-4.5). During an infection of the upper respiratory tract he developed signs of a new episode of purpura fulminans (INR 2.6). Additional anticoagulation therapy with LMW heparin (Clexane) and protein C concentrate was given while the oral anticoagulation therapy was continued. On the third day of this episode the boy suffered from pain of unknown origin. MRI of the abdomen and of the pelvis revealed nontraumatic osteonecrosis of the hip joint. After a few weeks of immobilisation no special treatment was necessary. One year later he was able to walk with no problem. CONCLUSION: Aseptic osteonecrosis of the hip joint is associated with a variety of disorders including vascular thrombosis and haemorrhage. Especially young children and handicapped patients with thrombophilia and pain of unknown origin are suspected to have thrombosis in atypical regions.

Child, Preschool↗
PubMed1999

Polyploidization and losses of chromosomes 1, 2, 6, 10, 13, and 17 in three cases of chromophobe renal cell carcinomas.

Clonal chromosome aberrations identified after short-term culture are presented for three cases of chromophobe renal cell carcinomas (RCC). All tumors revealed abnormal karyotypes with a varying proportion of polyploid tumor cells. Common numerical abnormalities were combined losses of chromosomes 1, 2, 6, 10, 13, and 17. Clonal karyotypic evolution was demonstrated in one case in which several related clones could be identified. An additional balanced translocation t(3;14)(p24;q22) observed in this case proved to be of constitutional nature by cytogenetic analysis of normal kidney cells and peripheral blood lymphocytes. These cytogenetic findings provide further evidence that chromophobe renal cell carcinomas are characterized by a highly specific combination of chromosomal losses most commonly including chromosomes 1, 2, 6, 10, 13, and 17.

Adenocarcinoma↗
PubMed1999

Papillary renal cell carcinoma with clear cell cytomorphology and chromosomal loss of 3p.

AIMS: Cytogenetic studies on renal cell carcinomas (RCCs) have disclosed a correlation between chromosome aberrations and histomorphological features. Nevertheless, it is still controversial whether the cytomorphology of the tumour cells (clear cell, chromophilic, chromophobe) or their growth pattern (nonpapillary, papillary) is more discriminative for the combined histomorphological-cytogenetic classification of RCCs. METHODS AND RESULTS: Three RCCs with papillary growth pattern and clear cell cytomorphology were analysed by classical cytogenetics using standard G-banding techniques. Each tumour displayed clonal aberrations leading to loss of terminal 3p chromosomal segments. Monosomy 14 was also consistently found. Trisomy 17 was not observed in any of the tumours. CONCLUSIONS: This series of three RCCs consisting of clear cells with papillary architecture revealed chromosomal aberrations characteristic for the conventional (clear cell) RCC. Irrespective of the predominant papillary growth pattern, none of the cases were characterized by trisomy of chromosomes 3q, 7, 8, 12, 16, 17 and 20 and loss of Y chromosome which are widely regarded as the most consistent genetic alterations for papillary RCC. Therefore, our cytogenetic findings provide evidence that papillary clear cell RCCs should be classified according to their cytomorphology rather than their growth pattern even when papillary architecture is prominent.

Adult↗
PubMed1999

Thoracic computed tomography of patients infected with the human immunodeficiency virus: relevance for the course of disease.

To determine the diagnostic accuracy and prognostic implications of thoracic computed tomography (CT) in patients with human immunodeficiency virus infection (HIV), CT scans of 154 HIV-infected patients (mean age, 41 years; range 23-65 years; 18 female) with suspicion of pulmonary disease were retrospectively reviewed for signs of disease by two investigators blinded to clinical data other than positive HIV serology. Abnormal CT features were correlated with CD4-T lymphocyte count, histologic or microbiologic diagnosis, and survival. Computed tomography detected features of pulmonary disease in 133 patients. A recent chest film was available in 96 patients, and it was normal in 16. In 17 of 99 patients (17%) with histologic or microbiologic correlation, pathologic CT features could be demonstrated, though histologic and microbiological studies were unrevealing. Median survival was 649 days. Confluent pulmonary infiltrates and bilateral masses on CT indicated advanced disease with a median survival of 115 days (n = 11, p = 0.0005) and 174 days (n = 15, p < 0.0001), respectively. The authors concluded that thoracic CT detects pulmonary lesions in an appreciable portion of HIV-infected patients in whom chest radiographs, microbiologic methods, or histology failed to establish a diagnosis, and that CT findings allow for an estimation of patient survival in acquired immunodeficiency syndrome.

Adult↗
PubMed1998

Characterization of a newly established endometrial stromal sarcoma cell line.

We describe a newly established human sarcoma cell line derived from an endometrial stromal sarcoma (ESS). The cell line has been maintained in long-term cell culture for more than 2 years. It has been repeatedly analyzed in terms of morphology, immunocytochemical features, ultrastructure and karyotypic characteristics. In contrast to uniform endometrial stromal differentiation in vivo, the tumor cells were shown to display distinct phenotypical heterogeneity in vitro. In addition to the predominant cell type, which retained sarcomatous differentiation, foci of epithelial-like cells were observed in the cell culture. Immunocytochemical and ultrastructural analysis demonstrated a mainly mesenchymal phenotype with signs of epithelial characteristics, such as expression of cytokeratins, and the presence of desmosomes and kinetocilia, respectively. Cytogenetic analyses in early and late passages revealed unbalanced translocations between chromosomes 3 and 6 and an additional i(19)(q10), as common karyotypic changes in all tumor cells, indicating a monoclonal origin. Our new cell line can be used as an in vitro model to study the mechanisms of heterogeneous differentiation patterns in ESS.

Aged↗
PubMed1998

Solitary enchondroma with clonal chromosomal abnormalities.

We report a case of a solitary enchondroma located in the head of the left fibula in a 50-year-old patient and present the findings of histopathologic investigation and cytogenetic analysis. The tumor revealed simple karyotypic abnormalities with t(8;17)(q23;p13) and loss of chromosomes 9, 19, and 22 as clonal chromosomal changes. Only a few enchondromas with chromosome aberrations have been published previously; nevertheless, it appears that benign and malignant cartilaginous tumors may have similar chromosomal abnormalities.

Bone Neoplasms↗
PubMed1998

Characterization of the human gene coding for the swelling-dependent chloride channel ICln at position 11q13.5-14.1 (CLNS1A) and further characterization of the chromosome 6 (CLNS1B) localization.

Expression cloning revealed a chloride channel (ICln) that we found to be fundamental for the regulatory volume decrease in a variety of cells. The chromosomal localization of the human ICln-gene showed two loci, one at chromosome 11 in position q13.5-q14.1, termed CLNS1A, and a second one at chromosome 6 at position p12.1-q13, termed CLNS1B. In this study, we offer a detailed characterization of the CLNS1A gene and provide the exact position (6p12) and sequence data of CLNS1B, an intronless gene 91.3% homologous to the coding region of CLNS1A.

Amino Acid Sequence↗
PubMed1998

Cytogenetic analysis of 11 renal oncocytomas: further evidence of structural rearrangements of 11q13 as a characteristic chromosomal anomaly.

We carried out cytogenetic analysis on 11 renal oncotytomas by using G-banding and DAPI-banding techniques. Four of our tumors exhibited structural rearrangements affecting chromosome 11 at band q13. Together with another case previously described by us, our tumors constitute the largest series of renal oncocytomas displaying translocations involving 11q13. A review of the literature disclosed only 6 similar oncocytomas, 1 tumor with a t(9;11)(p23;q12), 2 tumors with a nearly identical t(9;11)(p23;q13), and 3 tumors with a t(5;11)(q35;q13). Therefore, our findings provide further cytogenetic evidence that genes located on 11q12-13 may be involved in the tumorigenesis of renal oncocytomas.

Adenoma, Oxyphilic↗
PubMed1998

[Ultrastructural differential diagnosis of gastrointestinal stromal tumors].

Gastrointestinal stromal tumors (GIST) may present with myogen or neurogen differentiation, mixed differentiation or with morphological features which cannot be further specified. 14 GIST of the stomach (9), the duodenum (2) and small bowel (3) were examined by immunohistochemistry and electron microscopy. Diagnosis was consistent for such tumors located distally from the stomach, however, evaluation of GIST of the stomach was different (apart from one case). Light microscopy and immunohistochemistry did not allow to discriminate between the different subtypes of GIST, however, electron microscopy revealed cellular differentiation. Hence, ultrastructural analysis is an useful tool for diagnosis of GIST, particularly those of the stomach.

Adult↗
PubMed1998

Cytogenetic and morphologic characteristics of gastrointestinal stromal tumors. Recurrent rearrangement of chromosome 1 and losses of chromosomes 14 and 22 as common anomalies.

We present cytogenetic findings in five gastrointestinal stromal tumors (GISTs). Three of these five cases had abnormal karyotypes with clonal chromosomal aberrations. The most common karyotypic pattern was a combined loss of chromosomes 14 and 22 in a total of three cases. Among these cases, additional recurrent chromosomal abnormalities were loss of 1p and/or 9, detected in two cases each. Another karyotypic feature consisted of polyploidisation, leading to hypotetraploid chromosome numbers in one case. These cytogenetic results provide evidence for a characteristic karyotypic pattern consisting of -14 and -22 in a subset of GISTs.

Chromosome Aberrations↗
PubMed1997

Sequelae after modified Fontan operation: postoperative haemodynamic data and organ function.

OBJECTIVE: To investigate the specific sequelae of the Fontan operation, and particularly the potential sequelae of chronically elevated systemic venous pressure. DESIGN: A retrospective analysis of clinical and haemodynamic data and evaluation of organ function in 80 surviving patients undergoing modified Fontan operation for various forms of underlying functionally univentricular hearts. PATIENTS: 65 patients (81%) who had undergone a total cavopulmonary anastomosis and 15 an atriopulmonary anastomosis. Follow up ranged from 12 to 106 months (mean 54 (SD 23) months). RESULTS: 62 patients underwent postoperative cardiac catheterisation (mean systemic venous pressure 10.5 (2.5) mm Hg and cardiac index 3.1 (0.7) l/min/m2). Older age at operation was significantly correlated with both higher systemic venous pressure and lower cardiac index. Atrial arrhythmia was documented on Holter electrocardiogram in 17%. Protein losing enteropathy (with abnormal alpha 1-antitrypsin clearance) was found in 2/80 patients (2.5%). Ten patients had hypoproteinaemia, with a significantly higher incidence in patients after total cavopulmonary anastomosis and young age at operation. Liver function tests reflecting liver synthesis and metabolism were normal in all, whereas mild cholestasis was found in nearly 30%-predominantly in patients with a cardiac index of < 3 l/min/m2 (P = 0.045). Five patients (6.2%) developed atrial thrombosis. Coagulation factor analysis in 44 patients showed protein C deficiency in 11 (25%); laboratory signs of activation of the coagulation system were found in four of these (9%). None of the abnormal laboratory indices was significantly related to underlying cardiac malformation, postoperative systemic venous pressure, or follow up interval. CONCLUSIONS: A high proportion of clinically asymptomatic patients had abnormal laboratory findings on mid-term follow up. Detailed evaluation of organ function is necessary to detect the need for further diagnostic procedures before clinical symptoms develop.

Adolescent↗
PubMed1996

Prevalence of factor V Leiden in children with thrombo-embolism.

UNLABELLED: Hereditary resistance to the anticoagulatory action of activated protein C (APC resistance, APCR) was identified as a possible new thrombophilic factor in a high percentage (17%-60%) of young adults with thrombotic events. A single missense mutation (R506Q) due to a G/A transition (G1691A) in exon 10 of the factor V gene is regarded as the causative molecular defect, resulting in factor V Leiden which is correlated with APCR. Identification of this mutation by polymerase chain reaction-based methods is easy to perform and prevents pre-analytical and analytical errors in the coagulometric assay for APCR. Since the impact of this mutation in children with thrombo-embolic disease has not been determined to date, we initiated a multi centre prevalence study in two paediatric populations, with and without thrombo-embolic events. We compared 125 paediatric patients with thrombosis, divided into three different age groups (0 to < 0.5 years; > 0.5 to < 10 years; > 10 to < 18 years) with a normal population of 159 children. Although the mutation G1691A was found with an unexpectedly high prevalence of 12% in our normal controls, the prevalence was significantly higher in the age groups; 0 to < 0.5 years (26%) and > 10 to < 18 years (30%). In patients between > 0.5 and < 10 years the overall prevalence was similar to that of the control group (13%). However, in patients of this age with spontaneous thrombosis, G1691A was also a significant risk factor (5/17 approximately equal to 29%). Homozygosity for G1691A was detected in three patients but not in the control group. Including deficiencies of protein C, protein S, antithrombin, and the presence of anti-phospholipid antibodies, thrombosis was correlated with endogenous thrombophilic factors in 38/125 patients (30.4%). CONCLUSION: Our results emphasize the impact of factor V Leiden on thrombogenesis in children. However, the significance is age-dependent and may reflect the different physiology of haemostasis in the three age groups. The diagnostic workup of children with thrombosis should include tests for factor V Leiden. The correlation of factor V Leiden with the clinical course of thrombo-embolism in children is essential to establish rational guidelines for therapy and prophylaxis of APCR-related thrombosis which are not yet available.

Adolescent↗
PubMed1996

Blood pressure effects of hydrochlorothiazide, applied to the rat hypothalamus.

In the search for central actions of hydrochlorothiazide (HCTZ), the drug was injected directly into the hypothalamus (HTH) of hypertensive rats. This caused regular fall of blood pressure (BP) and development of a flat dose-response curve-both events resembling corresponding phenomena in systemic injections. In a small number of experiments, the drug caused a rise in BP. This result was enhanced when normotensive rats were injected into the HTH. It is concluded that the rat HTH bears two antagonistic receptors for HCTZ.

Animals↗
PubMed1996

Recent progress in oligonucleotide synthesis.

New blocking group combinations for the machine-aided oligoribonucleotide synthesis on solid phase material have been developed and tested regarding their general application. An acetal function for 2'-OH protection offers a series of advantages in the synthetic approach but special conditions have to be fulfilled in order to guarantee a selective cleavage of the temporary 5'-OH blocking group such as the dansylethoxycarbonyl or even the acid-labile dimethoxytrityl group in the chain elongation process. The final removal of the 2'-O-acetal function in the partially deblocked oligomer proceeds unexpectedly well under weak acidic conditions due to a supposed intramolecular acid catalysis.

Acetals↗
PubMed1996

Results of a screening for von Willebrand disease type 2N in patients with suspected haemophilia A or von Willebrand disease type 1.

A screening program for the detection of patients with von Willebrand disease type 2N (VWD 2N) was carried out in 177 unrelated patients previously diagnosed with haemophilia A and in 199 unrelated patients with VWD type 1 in comparison. By measuring the factor VIII (FVIII) binding capacity of von Willebrand factor (VWF), we detected 13 patients with VWD 2N within 8 unrelated families. The former diagnosis has been haemophilia A in 5 index patients, and VWD in the remaining 3. Included in this study were 14 patients with suspected haemophilia A, whose molecular analysis for mutations in the FVIII gene was unsuccessful. Five of them had VWD 2N. In all patients with the VWD 2N phenotype we were able to identify specific molecular defects in the corresponding DNA sequence of the FVIII binding domain of VWF. The most common defect was R91Q. Four patients from 4 families were homozygous for R91Q, six patients from 3 families were compound heterozygous for R91Q and a silent yet unidentified allele. The VWD 2N phenotype of father, daughter, and son in one family, was based on 2 different genotypes, compound heterozygosity for R91Q and VWD type 1 in the father and the daughter, and homozygosity for R91Q in the son. Two patients from one family were compound heterozygous for T28M and delta C2680-2685 in exon 18, and one patient was compound heterozygous for a novel candidate missense mutation in exon 18(E24K) and delta C2680-2685 in exon 18 which is regarded the most common defect causing severe VWD type 3. FVIII:C values of 0.07 and 0.14 IU/ml were observed in patients with the genotype T28M/delta C2680-2685 whereas in patients being homozygous or compound heterozygous for R91Q, FVIII:C was 0.19 +/- 0.071 IU/ml. In contrast to the other genotypes, E24K/delta C2680-2685 is correlated with a more severe haemophilic phenotype with a FVIII residual activity of only 0.01-0.02 IU/ml. This emphasizes the need for inclusion of the factor VIII binding assay in the diagnostic workup of suspected haemophilia A.

Adult↗