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G Faller

Publications and source records attributed to G Faller.

53 records · Page 3Linked to original sources
PubMed1997

Expression of the transcriptional regulator Egr-1 in experimental glomerulonephritis: requirement for mesangial cell proliferation.

The early growth response gene-1 (Egr-1), a zinc finger transcriptional regulator, was induced in a rat model of mesangioproliferative glomerulonephritis (GN). Northern blot analysis revealed a maximal 14.9-fold increase in glomerular Egr-1 mRNA at day 6 of GN. By immunohistochemistry Egr-1 protein expression was demonstrated to be mainly confined to glomerular mesangial cells (MC). To test whether Egr-1 directly regulates MC proliferation, cultured MCs were stimulated with platelet-derived growth factor (PDGF) after preincubation with different Egr-1 antisense oligonucleotides (ASOs). PDGF-induced rise in 3H-thymidine uptake by 83% and almost completely abrogated increase in MC number. We conclude that Egr-1 induction is of critical importance for PDGF-induced mitogenic signaling in MCs, and inhibition of Egr-1 in vivo may offer an approach to oppose glomerular MC proliferation in glomerular inflammatory disease.

Animals↗
PubMed1997

Histological evidence of an inflammatory reaction to suture material in the dog vas deferens.

OBJECTIVE: To evaluate changes in histology and semen variables after using an elastomeric-hydrogel matrix plug as a reversible vasectomy device in dogs, and to determine the potential applications for improving fertility after vasectomy reversal. MATERIALS AND METHODS: Semen samples from six adult male dogs were obtained after left vasal ligation, placement of the plug in the right vas deferens, and subsequent removal of the plug. The vasa, epididymides and testes were evaluated histologically in four of the dogs after removal of the implant. RESULTS: No sperm were present in the ejaculate after the plug was removed. Histological sections showed intraluminal spermatids in areas where the plug had been placed. The lumen was occluded, secondary to foreign-body giant-cell reaction, at the vasotomy suture site, but other areas of the was previously containing the implant remained patent after it was removed. CONCLUSIONS: There were no sperm in the ejaculate after the plug was removed because the vasal lumen was occluded as a result of an inflammatory reaction to the suture material. In contrast, areas that had contained the implant but without a vasotomy suture were not inflamed. We suggest that further trials comparing various suture materials are carried out to determine if patency rates can be improved during vasotomy closure or vasovasotomy.

Animals↗
PubMed1997

Mucosal expression and luminal release of epidermal and transforming growth factors in patients with duodenal ulcer before and after eradication of Helicobacter pylori.

BACKGROUND: Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF alpha) are potent gastric acid inhibitors and stimuli of mucosal growth and protection but their involvement in Helicobacter pylori associated duodenal ulcer has been little examined. AIM: To assess gastric acid secretion, plasma gastrin concentrations, mucosal content of EGF and TGF alpha, and mucosal expression of these peptides and their receptor (EGFr) as well as salivary and gastric luminal release of EGF under basal conditions and after pentagastrin stimulation in 10 healthy subjects and in 25 H pylori positive patients with duodenal ulcer before and after two weeks of triple anti-H pylori therapy and four weeks after the termination of this therapy. RESULTS: Pentagastrin stimulation caused a significant increase in salivary and gastric release of EGF both in healthy controls and patients with duodenal ulcers but in the patients, the eradication of H pylori resulted in several fold higher gastric luminal (but not salivary) EGF release than before the anti-H pylori therapy. Mucosal contents of immunoreactive EGF and TGF alpha and mucosal expression of EGF, TGF alpha, and EGFr in H pylori positive patients with duodenal ulcer were significantly higher than those in healthy H pylori negative controls and this increase persisted after eradication of H pylori. Basal plasma gastrin was significantly reduced after two weeks of triple therapy and four weeks after the H pylori eradication all ulcers were completely healed. CONCLUSIONS: (1) H pylori infection in patients with duodenal ulcer was accompanied by enhanced plasma gastrin and increased mucosal content and expression of TGF alpha, EGF, and EGFr; (2) H pylori eradication resulted in ulcer healing, reduction in plasma gastrin, and enhancement of gastric (but not salivary) luminal release of EGF, particularly after pentagastrin stimulation; and (3) enhanced mucosal content and expression of TGF alpha, EGF, and EGFr and increased luminal release of EGF may contribute to ulcer healing after eradication of H pylori.

Duodenal Ulcer↗
PubMed1997

Antigastric autoantibodies in Helicobacter pylori infection: implications of histological and clinical parameters of gastritis.

BACKGROUND: It has recently been shown that humoral antigastric autoreactivities occur in a substantial number of Helicobacter pylori infected patients. AIMS: To analyse the relevance of such antigastric autoantibodies for histological and serological parameters of the infection as well as for the clinical course. METHODS: Gastric biopsy samples and sera from 126 patients with upper abdominal complaints were investigated for evidence of H pylori infection using histology and serology. Autoantibodies against epitopes in human gastric mucosa were detected by immunohistochemical techniques. Histological and clinical findings of all patients were then correlated with the detection of antigastric autoantibodies. RESULTS: H pylori infection was significantly associated with antigastric autoantibodies reactive with the luminal membrane of the foveolar epithelium and with canalicular structures within parietal cells. The presence of the latter autoantibodies was significantly correlated with the severity of body gastritis, gastric mucosa atrophy, elevated fasting gastrin concentrations, and a decreased ratio of serum pepsinogen I:II. Furthermore the presence of anticanalicular autoantibodies was associated with a greater than twofold reduced prevalence for duodenal ulcer. CONCLUSION: The data indicate that antigastric autoantibodies play a role in the pathogenesis and outcome of H pylori gastritis, in particular in the development of gastric mucosal atrophy.

Adolescent↗
PubMed1997

Congenital microvillous atrophy: report of two cases.

2 infants with chronic severe diarrhoea from birth and with lethal outcome have been studied. Small intestinal biopsies were examined by light and electron microscopy. Severe villous atrophy, complete loss of microvilli or rudimentary forms, intracytoplasmic vesicles, and microvillous inclusions are the characteristic features of the disease. The etiology is unknown. A disturbance in the transport of brush-border proteins to the cell surface is assumed to be the reason for congenital microvillous atrophy.

Atrophy↗
PubMed1996

[Pathology of Helicobacter infection].

The colonization of gastric mucosa by Helicobacter pylori (H.p.) is a special form of chronic bacterial infection characterized by long term persistence of microbes because cause of an inefficiency of local immune responses. The resulting chronic gastritis causes decisive transformations of gastric mucosa. They comprise the acquisition of an active mucosa-associated lymphoid tissue as well as the development of glandular atrophy and intestinal metaplasia in the stomach. Both transformations change normal gastric functions, and create abnormal microenvironments with an increased risk for gastric cancer and lymphoma. Own recent investigations indicate, that the distribution and severity of chronic gastritis might be decisively influenced by a rise of antigastric autoimmune reactivity during the H.p. infection. The histologic examination of gastric biopsy samples is essential for an exact diagnosis of the complex pathogenic processes in chronic gastritis. In the future special emphasis of histologic analyses has to be put on the subtypes of gastritis, which are prone for complications and on the evaluation of gastritis remission after H.p. eradication.

Autoimmunity↗
PubMed1996

Antigastric autoantibodies in Helicobacter pylori gastritis: prevalence, in-situ binding sites and clues for clinical relevance.

Colonization of human gastric mucosa with Helicobacter pylori leads to chronic active gastritis and induces the occurrence of an acquired mucosa-associated lymphoid tissue (MALT) in the stomach. This remodelling of the gastric mucosa together with chronic antigen persistence may induce autoimmune reactions. The aim of this study was to investigate humoral autoimmune reactions to human gastric mucosa in H. pylori gastritis and their clinical relevance. Sera from patients with dyspeptic symptoms were tested for presence of IgG immunoglobulins against H. pylori. Gastric infection with H. pylori and alterations of gastric mucosa were demonstrated by histological examination of gastric biopsy specimens. All sera were tested for reactivity against human gastric mucosa by immunohistochemistry. Two different in-situ binding sites of antigastric autoantibodies were observed. Binding to canalicular structures within parietal cells was significantly correlated with antibodies to H. pylori, elevated basal gastrin levels and atrophy of gastric corpus glands. Our data indicate that autoimmune reactions to antigens in the human gastric mucosa occur in H. pylori gastritis and that they may play a role in the pathogenesis of the disease.

Adult↗
PubMed1996

Salivary and gastric luminal release of epidermal growth factor under basal conditions and after pentagastrin stimulation in healthy subjects and in duodenal ulcer patients before and after eradication of Helicobacter pylori.

Epidermal growth factor (EGF) is secreted by salivary and Brunner's glands and shows a potent inhibitory effect on gastric acid and stimulatory influence on mucosal growth and protection but little is known about the effect of the Helicobacter pylori (Hp) infection on the release of EGF. In this study the salivary and gastric concentrations of EGF have been measured and gastric mucosal expression of EGF has been determined in 25 Hp positive duodenal ulcer (DU) patients before and after the eradication of Hp (using triple therapy with omeprazole, 20 mg bd, amoxycillin, 500 mg qd and metronidazole, 500 mg bd for 2 weeks) and in 10 healthy controls under basal conditions and following pentagastrin (2 micrograms/kg-h) stimulation. Basal salivary and gastric concentrations of EGF were similar and no significant difference was found between DU patients and healthy controls. Pentagastrin infusion (2 micrograms/kg-h) caused a significant increase in EGF release into saliva and gastric juice both in healthy controls and DU patients but in DU patients the Hp eradication resulted in several folds higher basal and pentagastrin-induced gastric EGF content than that before the anti-Hp therapy, whereas such Hp eradication had no significant influence on basal and pentagastrin-induced salivary EGF. Antral mucosal expression of EGF in Hp-positive DU patients was significantly higher than that in healthy Hp-negative controls and this elevation persisted after eradication of Hp. Basal and pentagastrin-induced gastric acid outputs in Hp-positive DU patients were significantly higher than in healthy controls and they were slightly reduced after the triple therapy. In all DU patients, 4 weeks after termination of anti-Hp therapy, a complete ulcer healing occurred. We conclude that (1) the stomach is capable of secreting large amounts of EGF and pentagastrin appears to be a potent stimulus of salivary and gastric EGF release; (2) the Hp infection reduces the release of gastric EGF and the eradication of Hp results in the augmentation of basal and pentagastrin-induced EGF release into the stomach but not into the saliva and (3) since the eradication of Hp infection in DU patients resulted in DU healing and this was accompanied by an increase in EGF release, we conclude that EGF plays a crucial role in the DU healing process.

Duodenal Ulcer↗
PubMed1996

[Relevance of antigastric autoantibodies in Helicobacter pylori gastritis].

We have recently shown that antigastric autoantibodies occur in a considerable number of Helicobacter pylori (H. pylori) infected patients. Particularly, autoantibodies to canaliculi within parietal cells of human gastric body mucosa are strongly associated with H. pylori gastritis. In this study we analyzed the implications of this type of autoantibody for histological and for clinical parameters of the disease. 126 patients with upper abdominal complaints were included in our study. Several histological and clinical parameters were evaluated. Presence of anticanalicular autoantibodies is significantly correlated with a higher degree of gastritis in the body mucosa, with atrophic changes in the gastric mucosa, with elevated fasting gastrin levels and a decreased pepsinogen I/pepsinogen II ratio. These data indicate, that the host's autoimmune response to canaliculi of parietal cells is of relevance for the pathogenesis and outcome of H. pylori gastritis.

Atrophy↗
PubMed1996

[Apoptosis in chronic gastritis: correlation of glandular apoptosis with antigastric autoantibodies].

In the course of time, chronic gastritis results in gastric atrophy. A typical example is type A-gastritis. Parietal cell antibodies lead to a loss of glands in the corpus mucosa. Atrophy is preceded by a preatrophic state (active type A-gastritis). Recently, gastric autoantibodies could also be detected in Helicobacter pylori induced type B-gastritis and could be specified as canalicular and luminal antibodies. The question of this study was whether apoptosis is responsible for the loss of gastric epithelium. Gastric biopsies from normal mucosa, type B-gastritis and active type A-gastritis were analysed for the presence of apoptosis using the TUNEL-method. Type B-gastritis was subdivided in cases without autoantibodies, with canalicular and luminal autoantibodies and with both types. In each case antrum- and corpus-mucosa was available and 200 cells of the foveolar as well as of the glands were counted. Normal mucosa showed only few apoptotic cells. The number of apoptosis was significantly elevated in all cases of type B-gastritis in the whole antrum and in the foveolar epithelium of the corpus. Active type A-gastritis revealed the highest number of apoptosis in the gastric glands of corpus mucosa. Subdividing type B-gastritis the most interesting result was the cases with canalicular antibodies had a similar high number of apoptosis in the corpus glands as active type A-gastritis. These cases were in this regard significantly different from cases of type B-gastritis without autoantibodies. The findings suggest that gastric atrophy might be the result of apoptosis in the gastric epithelium and that, possibly, different types of type B-gastritis lead to atrophy in different regions of the stomach.

Adolescent↗
PubMed1995

Inflammatory, preneoplastic, and neoplastic changes of the gastric mucosa. Examinations by the AgNORT-technique.

The gastric surface epithelium of 101 antrum biopsies was examined by the AgNOR-technique. The material included normal mucosa, Helicobacter pylori gastritis, gastric ulcer, intestinal metaplasia type I and type III, dysplasia grades I-III and carcinoma. Starting from normal mucosa, a continuous increase in the number of AgNORs could be observed. At the same time, the size of the individual AgNOR-dots decreased. The entire AgNOR area per cell and the AgNOR quotient were ascertained. Groups of significant differences were found and could be clearly defined by cluster analysis. Intestinal metaplasia type I corresponded to inflammatory changes, whereas intestinal metaplasia type III was related to dysplastic lesions.

Biopsy↗
PubMed1994

[Thyrotropin-producing hypophyseal adenoma in a case with congenital thyroid gland hypoplasia].

A 56 year old mentally disabled woman of short stature was admitted to our hospital because of severe chest pain and dyspnoea. An extended myocardial infarction in the anterior wall was clinically found and confirmed by autopsy. On admission cretinism with massive myxedema was diagnosed, which was confirmed by subsequent laboratory findings. Only at the base of the tongue thyroid tissue 3 mm in diameter was found. In the anterior lobe of the pituitary gland areas with nodular hyperplasia and microadenomas of TSH-producing cells were detected. Thyrotroph adenomas in long standing hypothyroidism are rare. There are only few reports on congenital hypothyroidism as primary underlying disease.

Adenoma↗
PubMed1990

HAB-1, a new heteromyeloma for continuous production of human monoclonal antibodies.

To obtain suitable cell lines for the immortalisation of human lymphocytes, we constructed a heteromyeloma between the murine myeloma Ag8 and human lymphocytes from a highly malignant polymorphic, centroblastic B-cell lymphoma. The thioguanine-resistant and HAT-sensitive heteromyeloma HAB-1 neither secretes nor contains cytoplasmatic immunoglobulins, the cells being EBV negative but positively stained for HLA-BC and the human proliferation marker Ki-67. The karyotype consists of about 50 murine and 20 human chromosomes. The HAB-1 cells grow in suspension and have a doubling rate of about 25-30 h. In fusion experiments with spleen cells from stomach carcinoma patients HAB-1 cells show a 5-7 times higher fusion efficiency than murine Ag8 cells or another heteromyeloma SPM4-0 and give stable antibody producing products. The cell line will be made available to interested scientists.

Animals↗
PubMedDate not supplied

LOH analyses in the region of the putative tumour suppressor gene C13 on chromosome 13q13.

BACKGROUND: In previous studies we isolated a new cDNA fragment named C13 which is down-regulated in malignant prostate tissues. The corresponding gene is localized on chromosome 13q13 between the known tumour suppressor genes (TSG) BRCA-2 and RB-1. MATERIALS AND METHODS: Loss of heterozygosity (LOH) analyses were carried out in the region of C13 in order to investigate the importance of the new putative TSG for prostate cancer development. Using semiquantitative LOH analysis, we screened 21 prostate carcinoma patients of different tumour stages (pT2-pT4) for 14 microsatellite markers in the region of C13 (13q13) and in the flanking BRCA-2 and the RB-1 loci. RESULTS: For 18 (86%) patients LOH or allelic imbalances were found. We identified three to nine alterations in affected tumours per marker. An overall genetic alteration frequency per patient of 38% (86 of 225 informative cases) could be calculated. One important finding regarding the overall frequency of determined microsatellite instability is that the LOH/AI rate of 47% for the seven C13-associated markers was higher than for the four markers of the RB-1 locus (39%) and for the three BRCA-2 markers (25%). Surprisingly, defining LOH critical regions (LCR) for the investigated marker panel, eight of the ten affected LCR cases showed chromosomal imbalances simultaneously for the RB-1 and the C13 LOH markers. CONCLUSIONS: The high LOH rate for eight different microsatellite markers in and around the putative TSG locus C13 on chromosome 13q13 further supports an involvement of C13 in prostate tumourigenesis.

Aged↗