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K J Hengels

Publications and source records attributed to K J Hengels.

At least 19 recordsLinked to original sources
PubMed1997

Which peptic ulcers bleed? Results of a case-control study. DUSUK Study Group.

BACKGROUND: The incidence of ulcer bleeding has not decrease despite effective medical treatment of peptic ulcer disease. Numerous studies have been performed on risk factors for ulcer bleeding, but only a few studies have related the risk of developing ulcer bleeding to the risk of developing uncomplicated ulcer disease. METHODS: This study was performed as a multicenter interdisciplinary case-control study and was based on diagnosis by endoscopy, prospective data collection, and multivariate analysis. To every study patient with ulcer bleeding (case) one patient with uncomplicated peptic ulcer proven at endoscopy (control) was assigned with regard to sex, ulcer localization, and age (+/-5 years). The controls were randomly taken from three sources: inpatients, outpatients, and patients treated by a private physician. RESULTS: Owing to strict inclusion and exclusion criteria, 209 matched pairs were available for evaluation out of 401 patients with peptic ulcer bleeding. In univariate analysis the duration of ulcer pain and the number of previous ulcer treatments proved to be protective factors for ulcer bleeding. The intake of non-steroidal anti-inflammatory drugs (NSAID) as a whole, acetylsalicylic acid (aspirin), and paracetamol gave an increased risk for ulcer bleeding. Multivariate analysis identified four risk factors for peptic ulcer bleeding: lung disease, NSAID intake, no pretreatment with H2 blockers, and acetylsalicylic acid intake. CONCLUSIONS: The following patient groups represent a risk for peptic ulcer bleeding: multimorbid patients, receiving NSAID and/or aspirin, and patients with no previous ulcer history.

Aged↗
PubMed1995

Influence of lansoprazole on intragastric 24-hour pH, meal-stimulated gastric acid secretion, and concentrations of gastrointestinal hormones and enzymes in serum and gastric juice in healthy volunteers.

Twelve healthy volunteers (6 females, 6 males) between 26 and 36 years of age were enroled in this double-blind, randomized, placebo-controlled, three-way cross-over study. The objective was to determine the influence of lansoprazole (Agopton, Takeda Pharma GmbH, Aachen), a novel proton pump inhibitor, in doses of 30 and 60 mg, on the intragastric pH, on meal-stimulated gastric acid secretion and on the concentration of gastrointestinal hormones and enzymes in serum and gastric juice. Active drug or placebo had to be taken as single daily morning doses on an empty stomach for 7 days. Each wash-out period between drug application periods was 2 weeks long. Lansoprazole induced a dose-related increase in intragastric pH as well as a relevant reduction of basal acid output, meal-stimulated acid output and meal-stimulated secretion volume. 60 mg lansoprazole was significantly superior to 30 mg in increasing intragastric pH. The basal secretion volume in volunteers on 30 and 60 mg lansoprazole were lower than in volunteers on placebo. Serum gastrin and serum pepsinogen concentrations increased in a dose-dependent manner. Pepsin output and pepsin activity in gastric juice were slightly decreased in volunteers on 30 mg lansoprazole and markedly suppressed in volunteers on 60 mg lansoprazole 2 h after meal stimulation. Intrinsic factor concentration increased in volunteers on lansoprazole with a clear dose relationship. The evaluation of laboratory data and reported nonserious adverse events proved the relative safety of this new antiulcer agent.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1994

The epidemiology of low serum pepsinogen A levels and an international association with gastric cancer rates. EUROGAST Study Group.

BACKGROUND/AIMS: Low serum levels of pepsinogen A are indicative of chronic atrophy, a risk factor for gastric cancer. This study investigated the relationships between low pepsinogen A levels, Helicobacter pylori seropositivity, and gastric cancer rates in 17 populations worldwide. METHODS: In each center, about 200 randomly selected subjects (50 male and 50 female, aged 25-34 and 55-64 years) provided serum samples for pepsinogen analysis and H. pylori serology. RESULTS: Cumulative gastric cancer rates were associated with the prevalence of low pepsinogen A levels in men (coefficient, 0.15 [P = 0.06] for mortality; coefficient, 0.36 [P = 0.01] for incidence) but not women. The prevalence of low pepsinogen A levels was also correlated with H. pylori seropositivity in the older age group (r = 0.55; P = 0.02). Low pepsinogen A levels were significantly more common in the older group (7.5% vs. 2.1% in the younger group; P < 0.001), among women (5.5% vs. 4.1% in men; P = 0.04), and among nonsmokers (5.8% vs. 2.9% in current smokers; P = 0.001). CONCLUSIONS: Low pepsinogen A levels are more common in areas with a high seroprevalence of H. pylori and in men in areas with high rates of gastric cancer. The prevalence of low pepsinogen A levels increases with age, but the excess in women and nonsmokers could reflect factors other than gastric pathology.

Adult↗
PubMed1994

Effects of Helicobacter pylori on histamine and carbachol stimulated acid secretion by human parietal cells.

Helicobacter pylori (H pylori) infection is associated with hypo, normal, and hypersecretory disorders of the gastric mucosa. Pathophysiological pathways by which H pylori interacts with acid secretion are still unclear. The effects of H pylori on (14C) aminopyrine uptake by human parietal cells were examined as an indirect assay for acid secretion. Isolated oxyntic glands were stimulated with submaximal concentrations of histamine or carbachol and incubated with sonicates of different H pylori strains. Omeprazole and sonicates of Campylobacter jejuni served as positive and negative controls, respectively. Two of four H pylori strains reduced hydrochloric acid sequestration within the parietal cells significantly and in a dose dependent manner in up to 80%. Interaction with acid secretion may therefore constitute a factor contributing to a distinct pathogenicity of H pylori strains.

Aminopyrine↗
PubMed1994

Effect of Helicobacter pylori on dbc-AMP stimulated acid secretion by human parietal cells.

This study examines the effect of different H.p. strains (A-D) on dbc-AMP stimulated acid secretion by human parietal cells in vitro. H.p. strains A and D reduced acid secretion dose-dependently between 20 and 80%. In contrast, H.p. strains B and C had little or no effect. We conclude that H.p. strains vary in their ability to suppress acid secretion, and that the site of inhibition lies beyond the c-AMP level, possibly involving the K+H(+)-ATPase of the parietal cell. Interference with acid secretion may facilitate H.p. colonization of the stomach and may prove to be an important pathogenetic factor.

Aminopyrine↗
PubMed1994

[Visceral leishmaniasis with gastrointestinal involvement in a 30-year-old HIV infected patient].

We report the case of a 30-years old HIV-infected woman who suffered from recurrent fever up to 41 degrees C, loss of appetite, loss of 8 kg body weight and swelling of the cervical and inguinal lymph nodes. The diagnostic work-up revealed infection with leishmania in gastric and duodenal biopsies. The parasites were also found in the inguinal lymph nodes and in the bone marrow of the patient. According to patient's history the infection was acquired on a holiday in southern spain. The patient was treated with pentavalent antimony in combination with interferon gamma. Visceral leishmaniosis in immuno-suppressed patients is discussed and therapeutic approaches are described.

AIDS-Related Opportunistic Infections↗
PubMed1994

[Sclerosing cholangitis with papillary stenosis in an HIV-infected patients with Cryptosporidium infection].

We report the case of a 46-year old HIV-infected patient who suffered from severe recurrent diarrhoea for 18 months. In stool cultures cryptosporidiae were identified. The cryptosporidial enteritis was unresponsive to therapy. In the further course of cryptosporidial infection the patient developed HIV-associated cholangitis with increasing upper abdominal pain, progredient laboratory cholestasis and morphological changes indicating posthepatic cholestasis. Papillary stenosis with erosive papilitis caused by cryptosporidia was diagnosed. Sphincterotomy significantly improved the clinical status of the patient. Cholangitis with associated crytosporidial infection in a HIV-infected patient ist discussed and necessary diagnostic and differential therapeutic approaches are described.

AIDS-Related Opportunistic Infections↗
PubMed1994

Hereditary hemorrhagic telangiectasia associated with multiple pulmonary arteriovenous malformations and juvenile polyposis.

A case with multiple telangiectases of the gastrointestinal tract that caused recurrent bleeding is reported. The hemorrhagic telangiectases were associated with multiple pulmonary arteriovenous malformations leading to significant right-to-left shunting and in combination with an atrial septal defect to progressive right heart failure and finally to the death of the patient. Juvenile polyps and tubulovillous adenomas of the colon were removed. Hemicolectomy had to be performed because of carcinomatous infiltration originating from adenomatous epithelium developing in a juvenile polyp. The pathogenesis of hemorrhagic telangiectases is unknown. It is an important source of intestinal hemorrhage and may be complicated by the additional finding of arteriovenous fistulas and the occurrence of recurrent juvenile, adenomatous epithelium containing colonic polyps eventually leading to carcinoma. The present case suggests an inherited association of hemorrhagic telangiectases and juvenile polyposis. It also highlights that rapidly progressive right-to-left shunting rather than hemorrhagic anemia my be the major determinant of the course of the disease.

Adenomatous Polyposis Coli↗
PubMed1993

Prognostic significance of DNA ploidy in adenocarcinoma of the pancreas. A flow cytometric study of paraffin-embedded specimens.

BACKGROUND: The prognostic significance of tumor DNA ploidy in patients with cancer of the pancreas has not been defined because conflicting results have been reported. METHODS: DNA content was measured in 56 ductal adenocarcinomas of the pancreas. DNA ploidy status was evaluated by flow cytometry in nuclei isolated from paraffin-embedded tumor tissues. RESULTS: An abnormal DNA stemline was observed in 27 (48%) patients. The percentage of aneuploid tumors was significantly increased in tumors classified as Stage III/IV (53%) compared with those classified as Stage I (22%). A borderline significant association existed between DNA ploidy and radicality of surgery (P = 0.08). The median survival of patients with diploid carcinomas was 6.9 months (standard error, +/- 0.9) in comparison to 4.5 +/- 1.2 months for patients with aneuploid tumors (P = 0.013 by generalized Wilcoxon test; P = 0.023 by generalized Savage test). Although a selection bias cannot be excluded, survival of patients with a radical resection was longer than that of patients with a nonradical resection (P = 0.0008 and P = 0.0085, respectively). In addition, presence of distant metastasis (P = 0.0006 [Wilcoxon test] and P = 0.033 [Savage test]) could be identified as a prognostic factor. In a Cox regression model, results of surgery and DNA ploidy were independent prognostic variables. CONCLUSIONS: Because DNA ploidy has a significant impact on prognosis in pancreatic cancer, it should be used as a variable for stratified randomization of patients in therapeutic trials.

Adenocarcinoma↗
PubMed1993

Protein kinase C and adenylate cyclase as targets for growth inhibition of human gastric cancer cells.

In the human gastric adenocarcinoma cell line AGS the effects of the protein-kinase-C-activating phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA), the protein kinase C inhibitor staurosporine, the adenylate-cyclase activating agent forskolin, and the permeable dibutyryl-adenosine 3',5'-monophosphate (Bt2cAMP) on the proliferation were assessed. Cell counting followed 5 days of incubation. Prolonged activation of protein kinase C by TPA, inhibition of protein kinase C by staurosporine, activation of adenylate cyclase by forskolin or a direct increase of the intracellular cAMP level all result in a dose-dependent growth inhibition of AGS gastric tumour cells. Half-maximal inhibition was achieved at 100 pM for TPA, 1 nM for staurosporine, 20 microM for forskolin, and 600 microM for Bt2cAMP. It is concluded that protein kinase C and adenylate cyclase play a fundamental role in the growth of AGS gastric cancer cells. Interference with these enzymes involved in the signal transduction of growth regulation in tumour cells may represent a target in the development of new antiproliferative principles.

Adenocarcinoma↗
PubMed1993

Histogenetical investigations on adenocarcinomas of the esophagogastric junction. An immunohistochemical study.

The presence of Pepsinogen II (PG II), gastral mucin (2B5), CA 19-9, BW 494 and Cytokeratin 20 (CK 20) was investigated in 69 adenocarcinomas of the esophagogastric junction (15 carcinomas in Barrett's esophagus, 9 distal esophageal carcinomas, 31 carcinomas of the cardia and 14 subcardial carcinomas). Evidence of gastric differentiation (expression of Pepsinogen II and/or gastric mucin) was found in more than 50% of the Barrett's carcinomas and the carcinomas of the cardia, but only in 20% of the subcardial carcinomas. High rates of antigen expression were found for the "intestinal" markers CA 19-9 (between 55.5% and 100%) and BW 494 (between 42.9 and 86.7%). CK-20 expression was detected to a significantly higher degree in Barrett's carcinomas (73.3%) than in the other groups (between 29% and 44.4%). These data indicate that the distribution of adenocarcinomas with gastric and/or intestinal differentiation at the esophagogastric junction forms a continuum without clear-cut borders.

Adenocarcinoma↗
PubMed1993

Local gastric and serum amoxicillin concentrations after different oral application forms.

The high recolonization rate after monotherapy of Helicobacter pylori-positive gastritis may be due to insufficient local drug concentrations. To investigate the role of local diffusion, we measured levels of amoxicillin, a drug with good in vitro activity against H. pylori, in the mucosa and serum. One gram of amoxicillin was given to healthy volunteers as a tablet (n = 6) or as water-dissolved, fizzing "Tab" (n = 6). Gastroscopy with biopsies from the antrum, corpus, and fundus was performed at 30, 60, and 90 min. Concentrations in the mucosa were measured after homogenization with the agar diffusion method using Bacillus subtilis as the biological indicator. Serum samples, taken basally and every 15 min, were analyzed by high-pressure liquid chromatography. Drug levels in the fundus and corpus remained far below those in the antrum for both application forms. The highest concentrations were reached after 30 min, with bactericidal levels in the antrum in two of six subjects who took the tablet form and five of six subjects who used Tabs. At 60 and 90 min, almost all values were below the MBC for 90% of the strains tested. The concentrations in serum, however, rose continuously, to reach a maximum after 75 or 90 min. These results show that incomplete elimination may be due to subbactericidal concentrations of antibiotics with high in vitro efficiency at the desired site of action in vivo and that local diffusion in the mucosa is essential for therapeutic effectiveness against H. pylori.

Administration, Oral↗
PubMed1992

Peptic ulcer bleeding: medical and surgical point of view. Results of a prospective interdisciplinary multicenter observational study. DUSUK Study Group.

Various treatment policies and clinical disciplines compete for the treatment of bleeding peptic ulcer. In a prospective multicenter and interdisciplinary study performed during a 1-year period at ten hospitals in Düsseldorf, all patients admitted for peptic ulcer bleeding were recorded. The characteristics of patients admitted to surgical and to medical departments, the distribution of endoscopic treatment, indications for surgery, type of surgical procedures, and outcome were investigated. In the study period 387 bleeding peptic ulcers were recorded. Of these patients 82% were primarily admitted to medical and 18% to surgical departments. No differences in terms of severity of ulcer disease or bleeding activity were noted between the groups of medical and surgical patients. However, accompanying or underlying diseases were detected more often in patients admitted to medical departments. Endoscopy treatment was performed in the majority of patients with arterial spurting bleeding (88%) or a visible vessel (80%). Injection therapy with epinephrine or polidocanol was mainly used (78%). In 16% of cases the patients underwent operation; 44% of the patients primarily admitted to a surgical department were operated (medical departments, 10%). About half of the operated patients underwent emergency surgery; in the majority of cases resections were performed (gastric ulcer, 76%; duodenal ulcer, 56%). Overall mortality was 11%, with no difference between surgical and medical patients. A high mortality was observed in the subgroup of patients with late recurrent bleeding (27%). It is concluded that for optimal treatment of peptic ulcer bleeding intensive cooperation between physicians and surgeons is necessary, and that agreed and evaluated treatment policies are needed.

Aged↗
PubMed1992

Association of Crohn's disease and multiple sclerosis. Is there a common background?

Crohn's disease (CD) and multiple sclerosis (MS) share familial occurrence and similar epidemiological traits. Apart from one report of both diseases occurring among consanguineous relatives, only three cases of CD and MS in the same patient have thus far been described. We describe here a 29-year-old woman in whom MS developed in 1983 and CD in 1989. The MS may have been the result of a strongly HLA-associated genetic predisposition, while the additional development of CD may have been due either to genetic factors or perhaps simply to chance. Viewing this case in the context of epidemiological data, however, we suggest that the development of CD and MS is based on one or more common genetic factors acting in conjunction with other presumably exogenous factors and triggering HLA antigens to lead to one disease or the other.

Adult↗
PubMed1992

DNA aneuploidy in Crohn's disease and ulcerative colitis: results of a comparative flow cytometric study.

DNA ploidy and S-phase fractions were assessed by flow cytometry in colonic biopsy specimens from 28 patients with ulcerative colitis and 51 with Crohn's disease. Whereas only diploid DNA histograms were found in Crohn's disease and control subjects, three patients with ulcerative colitis exhibited DNA aneuploidy. In one case, aneuploidy was associated with low grade dysplasia. S-phase fractions were higher in ulcerative colitis (mean (SD) 17.8 (7.7)%) than in Crohn's disease (13.1 (4.6)%) or control subjects (14.2 (4.6)%), but did not correlate with either disease activity or duration in any group. In this study, aneuploidy was associated exclusively with ulcerative colitis, even in the absence of dysplasia. In view of the epidemiological differences in malignant colonic transformation between ulcerative colitis and Crohn's disease, this study suggests that flow cytometry may help to identify individuals with an increased cancer risk in ulcerative colitis.

Aneuploidy↗