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E G Hahn

Publications and source records attributed to E G Hahn.

At least 37 records · Page 2Linked to original sources
PubMed2005

Objective benefit of a 1-day training course in endoscopic hemostasis using the "compactEASIE" endoscopy simulator.

BACKGROUND AND STUDY AIMS: The Erlangen Active Simulator for Interventional Endoscopy (EASIE) was introduced in 1997 as a training model for interventional endoscopy. Objective evidence of the benefits of training with this model has not previously been published. As part of two long-term projects, the benefits of a 1-day training course with the "compactEASIE" simulator were evaluated. MATERIALS AND METHODS: Fourteen American and 18 French gastroenterology fellows were enrolled. These fellows were participants in the intensive groups performing training in endoscopic hemostasis, with a total number of 28 fellows in New York and 36 in France. Gastrointestinal endoscopy faculty members in New York and France evaluated and timed the fellows in four disciplines to establish baseline skills (manual skills; injection and coagulation; Hemoclip application; and variceal ligation) with the compactEASIE simulator. The trainees were reevaluated after an intensive 1-day course (with two or three fellows and one instructor per station), also including preparation and assistance for each procedure. The assessment (overall and parts) was done by expert tutors using an ordinal scale ranging from 1 to 10 (1 = poorest, 10 = best), recording also mistakes and performance time. The compactEASIE simulator, equipped with an upper gastrointestinal organ package and an artificial blood perfusion system, was used as the training tool. RESULTS: A highly significant improvement ( P < or = 0.001) was observed in the performance of all endoscopic techniques. A significant reduction in performance time was also observed with three of the four endoscopic techniques. Successful hemostasis was significantly improved in two out of three techniques. CONCLUSIONS: A 1-day training course on endoscopic hemostasis using the compactEASIE simulator is capable of improving the performance of hemostasis procedures. Long-term effects of repeated training sessions are currently subject of collaborative studies in New York and France.

Clinical Competence↗
PubMed2005

Variants of bcl-2 specific siRNA for silencing antiapoptotic bcl-2 in pancreatic cancer.

BACKGROUND AND AIMS: Pancreatic cancer remains a devastating diagnosis with only limited therapeutic options. Specific inhibition of expression of target genes has become possible using small interfering (si) RNAs. We therefore investigated how far siRNA specific for bcl-2 may serve as a therapeutic option for pancreatic cancer in vitro and in vivo. METHODS: siRNAs targeting two different regions in the bcl-2 gene were transfected to YAP C and DAN G pancreatic carcinoma cells and human foreskin fibroblasts. Permutations were generated by changing 3' and 5' overhangs and varying the length of the paired RNA duplex. Transfection efficacy was determined using FITC labelled siRNAs and fluorescence microscopy. Cell survival and apoptosis were quantified at 24-120 hours. Pancreatic cancer xenografts in male nude mice were treated intraperitoneally with siRNAs daily for 24 days. siRNA pharmacokinetics in vivo were assessed using radioactively labelled siRNAs. Total protein and RNA were extracted for western Blot analysis and quantitative polymerase chain reaction. RESULTS AND CONCLUSIONS: Bcl-2 specific siRNAs specifically inhibited expression of the target gene in vitro and in vivo. Antiproliferative and proapoptotic effects were observed in tumour cells but not in fibroblasts or non-malignant tissues. siRNA permutations and diverse overhangs influenced gene silencing efficacy. siRNA was quickly distributed to all organs and excreted via the kidney and liver. Bcl-2 specific siRNA is a promising adjunctive treatment for pancreatic carcinoma.

3' Untranslated Regions↗
PubMed2005

Prostaglandins as mediators of COX-2 derived carcinogenesis in gastrointestinal tract.

This review was designed to show the role of expression of cyclooxygenase (COX)-1 and COX-2 in the cancerogenesis of esophagus, stomach and colon. Unlike COX-1, which is expressed in the normal esophago-gastro-colonic mucosa, COX-2 was found to be expressed mainly in the pre-cancer changes in the mucosa including Barrett's esophagus, Helicobacter pylori (H. pylori)-induced gastritis and inflammatory changes in colonic mucosa. In Barrett's esophagus, prostaglandins (PGs) derived from upregulated COX-2 contribute to the progression of low-grade to high-grade dysplasia and finally to cancer. In chronic gastritis induced by chronic H. pylori infection, overexpression of COX-2 is probably induced by inflammatory cytokines, growth factors, especially gastrin and reactive oxygen species leading to mutagenesis and subsequent metaplasia, dysplasia and cancer formation. The imbalance between cell proliferation and apoptosis caused mainly by products of COX-2 leads to cancerogenesis. Similarly, in colorectal cancer the overexpression of COX-2, possibly induced by the action of growth promoting factors including progastrin and gastrin and overexpression of survivin contribute to the colorectal cancerogenesis that could be, at least in part, amended by the treatment with specific COX-2 inhibitors. We conclude that: 1) COX-2-derived PGs play a key role in the tumorigenesis in the gastrointestinal tract; 2) The tumor-promoting effect of PGs may be attributed to their ability to stimulate cell proliferation and migration, to inhibit the apoptosis and to increase angiogenesis and invasiveness; 3) In accordance to the proposed major role of COX-2 in cancerogenesis, selective COX-2 inhibitors have been shown in numerous studies to exhibit strong chemopreventive effect on the development of gastrointestinal cancers.

Animals↗
PubMed2005

Significance of salicylate intolerance in diseases of the lower gastrointestinal tract.

Salicylate intolerance is defined as a nonspecific antigen-induced pseudo-allergic hypersensitivity reaction which can occur upon contact of an organism with salicylic acid, its derivatives or other related organic or inorganic acids of similar chemical structure. Since the effects of nonsteroidal anti-inflammatory drugs (NSAID) intolerance are by no means always severe or life-endangering but may just as well present as oligosymptomatic or local disorders (e.g. abdominal pain, diarrhea, we decided to evaluate the characteristics of patients with salicylate intolerance on the basis of gastroenterological case material of Medical Department I of Erlangen University. On the basis of the findings from the Erlangen interdisciplinary data register of chronic inflammatory gastrointestinal disease, the signs and symptoms of NSAID intolerance were found to constitute a diagnosis of great practical import to clinical medicine (allergology, dermatology, immunology, other disorders etc.) including gastroenterology. For approx. 2-7% of all patients with inflammatory bowel syndrome and food allergies this poses a new diagnostic and therapeutic challenge which may concern physicians from any of the disciplines involved. When presented with patients with chronic active disease who are suffering from these symptoms one should, therefore, in future give greater thought to the possibility of salicylate intolerance, all the more as there are meaningful dietetic, diagnostic and therapeutic options available for these persons.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2004

Exogenous and endogenous ghrelin in gastroprotection against stress-induced gastric damage.

Ghrelin, identified in the gastric mucosa has been involved in control of food intake and growth hormone (GH) release but little is known about its influence on gastric secretion and mucosal integrity. The effects of ghrelin on gastric secretion, plasma gastrin and gastric lesions induced in rats by 75% ethanol or 3.5 h of water immersion and restraint stress (WRS) were determined. Exogenous ghrelin (5, 10, 20, 40 and 80 microg/kg i.p.) increased gastric acid secretion and attenuated gastric lesions induced by ethanol and WRS and this was accompanied by the significant rise in plasma ghrelin level, gastric mucosal blood flow (GBF) and luminal NO concentrations. Ghrelin-induced protection was abolished by vagotomy and attenuated by suppression of COX, deactivation of afferent nerves with neurotoxic dose of capsaicin or CGRP(8-37) and by inhibition of NOS with L-NNA but not influenced by medullectomy and administration of 6-hydroxydopamine. We conclude that ghrelin exerts a potent protective action on the stomach of rats exposed to ethanol and WRS, and these effects depend upon vagal activity, sensory nerves and hyperemia mediated by NOS-NO and COX-PG systems.

Adrenergic Agents↗
PubMed2004

Implementation of a computer-assisted monitoring system for the detection of adverse drug reactions in gastroenterology.

AIM: To investigate the effectiveness of a computer monitoring system that detects adverse drug reactions (ADRs) by laboratory signals in gastroenterology. METHODS: A prospective, 6-month, pharmaco-epidemiological survey was carried out on a gastroenterological ward at the University Hospital Erlangen-Nuremberg. Two methods were used to identify ADRs. (i) All charts were reviewed daily by physicians and clinical pharmacists. (ii) A computer monitoring system generated a daily list of automatic laboratory signals and alerts of ADRs, including patient data and dates of events. RESULTS: One hundred and nine ADRs were detected in 474 admissions (377 patients). The computer monitoring system generated 4454 automatic laboratory signals from 39 819 laboratory parameters tested, and issued 2328 alerts, 914 (39%) of which were associated with ADRs; 574 (25%) were associated with ADR-positive admissions. Of all the alerts generated, signals of hepatotoxicity (1255), followed by coagulation disorders (407) and haematological toxicity (207), were prevalent. Correspondingly, the prevailing ADRs were concerned with the metabolic and hepato-gastrointestinal system (61). The sensitivity was 91%: 69 of 76 ADR-positive patients were indicated by an alert. The specificity of alerts was increased from 23% to 76% after implementation of an automatic laboratory signal trend monitoring algorithm. CONCLUSION: This study shows that a computer monitoring system is a useful tool for the systematic and automated detection of ADRs in gastroenterological patients.

Adolescent↗
PubMed2004

[Recurrent bouts of fever accompanied by abdominal pain and emesis].

A 34 year-old Turkish patient was admitted to hospital several times with the same symptoms of abdominal pain, fever up to 39.2 degrees C and vomiting. The diagnosis always was an acute attack of chronic pancreatitis. The inflammation scores in the blood were high and he had a moderate increase in pancreatic enzymes. He always got well in a few days on a strict diet and regime of analgesics. Taking these symptoms and his ethnic affiliation into consideration, differential diagnosis should include familial Mediterranean fever (FMF). Therapy with colchicine should be initiated even if genetic testing does not reveal the mutation characteristics for FMF. Immediate and consistent therapy helps to avoid amyloid nephropathy as the most dangerous complication of this disease.

Abdominal Pain↗
PubMed2004

Duodenal alkaline secretion: its mechanisms and role in mucosal protection against gastric acid.

Duodenal mucosa, especially its proximal portion, is exposed to intermittent pulses of gastric acid (H+). This review summarises the mechanisms of duodenal bicarbonate (HCO3-) secretion and their role in protecting duodenal epithelium against gastric H+. Duodenal epithelium is a leaky barrier against gastric H+, which diffuses into duodenocytes, but fails to damage them due to: (a) an enhanced expression of cyclooxygenase, producing protective prostaglandins and expression of nitric oxide synthase, releasing nitric oxide, both stimulating duodenal HCO3- secretion and (b) the release of several neurotransmitters also stimulating HCO3- secretion such as vasoactive intestinal peptide, pituitary adenylate cyclase-activating polypeptide, acetylcholine and melatonin. At the apical duodenocyte membrane, several HCO3-/Cl- anion exchangers operate in response to luminal H+ to extrude HCO3- into duodenal lumen. In baso-lateral duodenocyte membrane, both non-electrogenic and electrogenic Na+-HCO3- cotransporters are activated after exposure of duodenum to gastric H+, causing inward movement of HCO3- from extracellular fluid to duodenocytes. There are also at least three Na+/H+ exchangers, eliminating H+ which diffused into these cells. The Helicobacter pylori infection with gastric metaplasia in the duodenum and bacterium inoculation results in the inhibition of HCO3- secretion by its endogenous inhibitor dimethyl arginine, resulting in ulcerogenesis.

Bicarbonates↗
PubMed2004

Complete remission with long-term survival in a patient with esophageal carcinoma and a tracheoesophageal fistula after treatment with the AIO regimen and bi-weekly cisplatin.

INTRODUCTION: To date, only few reports are available on patients with esophageal carcinoma containing a tracheoesophageal fistula under chemotherapy. CASE REPORT: A 56-year-old patient presented to the hospital with a stenosing squamous cell carcinoma of the esophagus containing a tracheoesophageal fistula 3 cm above the carina. After placement of a Port-a-Cath and adequate hydration he received weekly 500 mg/m (2) i. v. folinic acid (FA) as a 1 - 2-hour infusion and 2000 mg/m (2) 5-fluorouracil (5-FU) as a 24-hour infusion (24-h inf.) (AIO regimen) with prior application of bi-weekly 50 mg/m (2) i. v. cisplatin. A tracheal Y-Dumont metallic stent was inserted prior to initiating systemic treatment. The patient's alimentation was completely parenteral. After three cycles of chemotherapy (six months) the patient revealed complete remission (CR) with closure of the tracheoesophageal fistula. The tracheal Y-Dumont stent could be removed and the patient had oral alimentation restored. 29 months after initiating treatment he is without evidence of disease. CONCLUSION: Patients with esophageal carcinoma containing a tracheoesophageal fistula might benefit from chemotherapy and should not be generally excluded from systemic treatment.

Antineoplastic Agents↗
PubMed2004

Successful laserlithotripsy in Bouveret's syndrome using a new frequency doubled doublepulse Nd:YAG laser (FREDDY).

Gastric outlet obstruction as a result of gallstone (Bouveret syndrome) is a rare but serious complication of cholelithiasis. In many cases, surgery has been conducted for treatment. In recent years, minimal invasive treatment modalities (e.g. shockwave lithotripsy) have been shown to be effective in some of those patients. Laserlithotripsy has so far been described in two cases with a Rhodamine-6G dye laser. We present the case of a 90-year-old woman with duodenal obstruction due to a huge gallstone. The patient was referred to our hospital because attempts at endoscopic extraction and extracorporeal shockwave lithotripsy had failed. The man was treated successfully in just one session with a new cost-efficient frequency doubled doublepulse Nd:YAG laser (FREDDY) using a total of 5726 laser pulses (120 mJ pulse energy, 10 Hz pulse repetition rate) and recovered rapidly. Laserlithotripsy can be considered an effective non-invasive therapeutic alternative to surgical treatment in Bouveret's syndrome, especially in old or high-risk patients.

Aged↗
PubMed2004

The compact Erlangen Active Simulator for Interventional Endoscopy: a prospective comparison in structured team-training courses on "endoscopic hemostasis" for doctors and nurses to the "Endo-Trainer" model.

BACKGROUND: In 1997 Hochberger and Neumann presented the "Erlangen Biosimulation Model" (commercialized as the "Erlangen Endo-Trainer") at various national and international meetings. The new compactEASIE is a simplified version of the original "Biosimulation Model" (Endo-Trainer) and is specially designed for easy handling. CompactEASIE is reduced in its features, focusing exclusively on flexible endoscopy training. The acceptance of training in endoscopic hemostasis is accepted by workshop participants, as evaluated by a questionnaire on both models. METHODS: Eleven structured courses on endoscopic hemostasis for doctors and nurses organized by the same endoscopists from 3/1998 to 5/1999 were evaluated using one of both models. The questionnaires were filled in by 207/291 trainees (71%). The Endo-Trainer was used in 4 (n = 103) and the compactEASIE in 7 courses (n = 104). Both simulators were equipped with identical types of specially prepared pig-organ packages consisting of esophagus, stomach and duodenum, including artificial sewn-in vessels, polyps and varices. Blood perfusion was done with a roller pump connected to the sewn-in vessels and blood surrogate. All workshops were identical concerning the course structure: a 30-min theoretical introduction on ulcer bleeding was followed by 2 h of practical training in injection techniques and hemoclip application. The second part of variceal therapy consisted of a 30-min theoretical introduction prior to 2 h of practical training on sclerotherapy, band ligation and cyanoacrylate application. Finally, a questionnaire on the trainees' pre-experience and their rating of the different workshop sections was handed out to each participant. RESULTS: Previous endoscopic experience was comparable in both groups. The training in both simulators was highly accepted by the trainees (compactEASIE 95% excellent and good versus EASIE (Endo-Trainer) 97%) and did not show any significant difference (P = 0.493). Even in the assessment of the single techniques, no statistical difference was observed. Furthermore, the assessments of the closeness to reality and the endoscopic environment in both simulators were identical. CONCLUSIONS: Both simulators (Endo-Trainer, compactEASIE) are excellent educational tools for interventional endoscopy with a high level of acceptance. The easy-to-handle, "lightweight" compactEASIE is a significant, progress tool for the future.

Clinical Competence↗
PubMed2004

Readmissions and adverse drug reactions in internal medicine: the economic impact.

BACKGROUND: Recent studies show that nearly half of the hospitalized patients are readmitted within 6 months from discharge. No data exist about the relationship between adverse drug reactions (ADRs) and readmittance to a department of internal medicine. OBJECTIVES: The primary aims of the study were to determine if ADRs could be used as predictors for recurrent hospitalizations in internal medicine and to evaluate the economic impact of ADRs on hospitalization costs. DESIGN AND SETTING: A cohort-based, prospective, 18-month pharmacoepidemiological survey was conducted in the Department I of Internal Medicine at the University Hospital of Erlangen. All patients were intensively monitored for ADRs by a pharmacoepidemiological team. ADRs were evaluated for their offending drugs, probability, severity, preventability and classified by WHO-ART. During a 6-month period ADR-positive patients were matched to non-ADR patients applying diagnosis-related group categorization in order to measure the impact of ADRs on the duration and frequency of hospitalization. RESULTS: Of 1000 admissions 424 patients had single admissions and 206 patients had recurrent readmissions (min 1, max 9). The prevalence of readmissions was 37% (n = 370). In 145 (23%) of 630 patients, 305 ADRs were observed. The ADR incidence was similar in first admissions and readmissions. ADRs were not found to predict further readmissions and lack of ADRs did not preclude readmissions. ADRs caused hospitalizations in 6.2% of first admissions and in 4.2% of readmissions. According to the Schumock algorithm 135 (44.3%) ADRs were found to be preventable. The occurrence and numbers of ADRs per admission were found to prolong hospitalization period significantly (r = 0.48 and 0.51, P < 0.001, n = 135). Of 9107 treatment days 20% were caused by in-house (1130 days) and community-acquired ADRs (669 days). In admissions and readmissions 11% (>973 days) of all treatment days were judged to be preventable. CONCLUSIONS: Intensified drug monitoring supported by information technology in internal medicine is essential for early detecting and prevention of ADRs and saving hospital resources.

Adolescent↗