Search PubMed⌕ Search

Biomedical subjects

A Imdahl

Publications and source records attributed to A Imdahl.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Percutaneous placement of feeding tubes for long-term nutrition and decompression. Indications, techniques and complications].

In the recent past, PEG/PEJ has found worldwide acceptance. The uncomplicated nature of the method has resulted in a considerable increase in endoscopic gastrostomies. Provided that the method is properly applied, and appropriate aftercare is offered, complications rarely occur. In principle, the indications are chronic diseases requiring tube feeding for longer than one month, such as cachexia in patients with cancer or stenotic tumors of the mouth and throat, or of the upper gastrointestinal tract.

Aged↗
PubMed2000

Impact of 18F-FDG-positron emission tomography for decision making in colorectal cancer recurrences.

Diagnostic imaging for suspected tumour recurrence of primary colorectal cancer frequently lacks specificity and sensitivity. The impact of whole body 18F-FDG-positron-emission tomography (PET) on detection of local recurrences and hepatic or pulmonary metastases was evaluated in a prospective study. Results were compared with computed tomography (CT), ultrasonography, magnetic resonance imaging and conventional chest X-ray. The study included 71 patients (77 investigations) with suspected local recurrence, hepatic metastases or unexplained raised level of the tumour marker carcinoembryonic antigen (CEA). The results demonstrate that 18F-FDG-PET was clearly superior to CT with regard to detection of hepatic metastases. Sensitivity was 1.0 and specificity 0.98 compared with 0.87 and 0.91 for CT. In four cases, 18F-FDG-PET clarified otherwise unclear local recurrences. In five patients, 18F-FDG-PET showed pulmonary metastases that had previously been unknown. In a total of 16 patients (20.8%), 18F-FDG-PET provided additional information leading to a change of the treatment strategy. 18F-FDG-PET clearly has the ability to detect colorectal tumour recurrence and its metastases in a whole body format. Therefore, it may be applied in the follow-up of patients with primary colorectal cancer. Despite the costs, it is certainly recommended for patients with an otherwise unclear increase of CEA level or with unproven local recurrence.

Adult↗
PubMed2000

Is MIB-1 proliferation index a predictor for response to neoadjuvant therapy in patients with esophageal cancer?

BACKGROUND: The overall survival rate for patients with an esophageal cancer remains poor. As a consequence, preoperative chemoradiation was introduced for patients with tumor stage T >1 M0 regardless of tumor histology or localization. However, factors predicting response to this therapy pretherapeutically are largely unknown. METHODS: Clinical results of preoperative chemoradiation were investigated. The rates of proliferation and apoptosis were determined in pretherapeutic tumor samples and correlated with tumor response and long-term survival after surgery. RESULTS: A complete tumor response due to chemoradiation (n = 42; cervically localized tumors excluded) was achieved in 11 patients (26%) after resection. Five-year survival rate was significantly improved in these patients compared with those who did not respond to chemoradiation (48% versus 5.5%; P = 0.003). Chemoradiation was performed without benefit in 43%. Perioperative hospital mortality rate was 14.3% in all patients. No correlation of apoptosis with response to chemoradiation or postoperative long-term survival was observed. However, there was a clear correlation between the proliferation rate as determined by MIB-1 immunohistology. Five-year survival rate of patients with a proliferation index (PI) >/=39% was 38% compared with 0% in tumors with a PI <39%. Tumors with a PI >/=39% responded to chemoradiation in 71.4%, but 100% of tumors with a PI <39% did not. Mean survival time of these patients was 33 months and 11 months, respectively (P = 0.015). CONCLUSIONS: The results indicate that the PI may be used for stratification of patients treatment prior surgery. However, these results need further validation in larger patient numbers in the search for factors indicating response pretherapeutically to preoperative chemoradiation in esophageal cancer.

Adenocarcinoma↗
PubMed1999

Expression of gastrin/CCK-B receptors does not lead to a mitogenic response to gastrin in two colon cell lines.

To clarify the impact of the classic gastrin/CCK-B receptor on the growth of benign and malignant colonic cells, two permanent cell lines expressing this receptor have been established. The conditionally immortalized nonmalignant colonic cell line YAMC and the colonic carcinoma cell line SW 403 were stably transfected with a plasmid encoding the gastrin/CCK-B receptor (GR), or with plasmid alone (V). Expression of the gastrin/CCK-B receptor in the transfected YAMC-GR and SW 403-GR cells was demonstrated by gastrin binding experiments. The YAMC-GR cell line did not respond mitogenically to pentagastrin or gastrin(17) in vitro and was not tumorigenic. The SW 403-GR cell line was stimulated by gastrin(17) in vitro, but the growth patterns of SW 403-GR and SW 403-V were the same in nude mice with cells injected either subcutaneously or into the spleen. These results provide further evidence that the gastrin/CCK-B receptor is not responsible for gastrin-stimulated growth in colonic tumors.

Animals↗
PubMed1999

Molecular biological observations in some rare neoplasms: DNA ploidy and cell cycle data in liposarcoma and malignant fibrous histiocytoma.

INTRODUCTION: The prognostic significance of tumor DNA ploidy and cell cycle analysis for long-term survival has been examined in 19 patients with liposarcoma or malignant fibrous histiocytoma. In many cases, different tumor areas of primary tumors and local recurrences have been analyzed to reveal intratumoral heterogeneity. RESULTS: Among the primary tumors, there were eight aneuploid tumors, three of which showed diploid and aneuploid tumor regions. Correlations among DNA ploidy, grading, percentage of S-phase cells and infiltrative growth pattern of the tumors could be demonstrated. Poorly differentiated tumors (G3) showed aneuploidy in six of eight patients. Aneuploid tumors showed S-phase cells in 17.2% (range 3.2-38.1%), which was higher than the percentage of S-phase cells in diploid tumors (9.4%, range 2.1-27.4%). Aneuploid tumors showed a more infiltrative growth pattern (6 of 8 patients) than diploid tumors (6 of 11 patients). The median survival time of patients with diploid tumors was 86.5 months (8-144 months), compared with 40.9 months (11-54 months) for patients with aneuploid tumors. CONCLUSION: DNA ploidy and percentage of S-phase cells may be considered as prognostic factors.

Aneuploidy↗
PubMed1999

Evaluation of positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose for the differentiation of chronic pancreatitis and pancreatic cancer.

BACKGROUND: The clinical presentation of patients with pancreatic cancer may resemble the clinical picture of chronic pancreatitis. A definitive preoperative diagnosis is not always obtained in patients with a history of chronic pancreatitis despite the use of modern imaging techniques. Operative strategy therefore remains unclear before operation in these patients. METHODS: Positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (FDG) was introduced recently into clinical oncology because of its ability to demonstrate metabolic changes associated with various disease processes. The impact of FDG-PET on the differentiation of chronic pancreatitis and pancreatic cancer was investigated. FDG-PET was performed in 48 patients with chronic pancreatitis (n = 12), acute pancreatitis (n = 3) and pancreatic cancer (n = 27), and in controls (n = 6). Histological examination was undertaken in all cases except controls. The FDG-PET results were obtained without knowledge of results of other imaging procedures. The results were then compared with those of computed tomography, ultrasonography, endoscopic retrograde cholangiopancreaticography, operative findings and histology. PET images were analysed semiquantitatively by calculating a standard uptake value (SUV) 90-120 min after application of the tracer. RESULTS: Cut-off values were validated as follows: SUV greater than 4.0 for pancreatic cancer, SUV of 3.0-4.0 for chronic pancreatitis, and SUV of less than 3.0 for controls. Sensitivity and specificity of PET imaging were 0.96 and 1.0 for pancreatic cancer, and 1.0 and 0.97 for chronic pancreatitis. In five cases only FDG-PET led to the correct preoperative diagnosis. CONCLUSION: The results give further evidence that FDG-PET is an important non-invasive method for the differentiation of chronic pancreatitis and pancreatic cancer. Delayed image acquisition in the glycolysis plateau phase permits improved diagnostic performance. This imaging technique is extremely helpful before operation in patients with an otherwise unclear pancreatic mass, despite its costs.

Adult↗
PubMed1997

The influence of ischemic bowel wall damage on translocation, inflammatory response, and clinical course.

BACKGROUND: While vascular patency and overall viability of the gut can be evaluated perioperatively, damage to the mucosal barrier can hardly be judged in the perioperative setting and, moreover, will probably determine the clinical course. METHODS: In 19 consecutive cases with intestinal ischemia, the clinical course was correlated to the severity of the disease (APACHE II; Septic Severity Score, SSS), the intraabdominal and systemic inflammatory response, and the translocation of bacteria and endotoxin. RESULTS: The comparison of the 10 survivors with the nonsurviving group revealed no differences as to the length of history, serum lactate levels, white blood cell counts, body temperature, markers of the inflammatory response, or quantity and macroscopic quality of the exudate. Differences were found in intraperitoneal bacteriology (prevalence 0.37, negative predictive value for lethal outcome 0.8), endotoxin concentrations in the exudate (P = 0.02) and in the plasma (P = 0.015), fibrinopeptide A levels (exudate P = 0.036; plasma P = 0.015), PGE2 plasma concentration (P = 0.0357), and APACHE II (P = 0.0034) and SSS (P = 0.0027) values. CONCLUSION: The clinical course of ischemic bowel wall necrosis seems to depend on the severity of the disease at admission and on the integrity of the mucosal barrier rather than on inflammatory response, therapeutic measures, or supportive treatment.

APACHE↗
PubMed1997

Glycine-extended gastrin acts as an autocrine growth factor in a nontransformed colon cell line.

BACKGROUND & AIMS: The hypothesis that progastrin-derived peptides act as autocrine growth factors for colorectal carcinomas has generated considerable interest. However, the influence of autocrine gastrins on nontumorigenic colonic cells has not been investigated. This study tested the above hypothesis in the nontumorigenic, conditionally immortalized mouse colon cell line YAMC. METHODS: The effects of expression of antisense or sense gastrin messenger RNA, treatment with antibodies against progastrin-derived peptides, or treatment with gastrin receptor antagonists on YAMC cell proliferation were measured. RESULTS: YAMC clones expressing antisense gastrin messenger RNA had reduced levels of immunoreactive progastrin-derived peptides and a reduced rate of proliferation, relative to vector only-transfected cells. Glycine-extended gastrin17, but not amidated gastrin17, reversed the antisense-induced inhibition of proliferation and stimulated the proliferation of sense- or vector only-transfected cells. YAMC cells bound 125I-glycine-extended gastrin17 (Kd, 0.36 nmol/L, 1810 sites/cell), but not 125I-amidated gastrin17, and binding was unaffected by gastrin receptor antagonists including benzotript. Proliferation of all YAMC clones was partially inhibited either by an antibody selective for glycine-extended gastrin or by preincubation with benzotript, and the inhibitory effects were additive. CONCLUSIONS: YAMC cells use nonamidated progastrin-derived peptides as autocrine growth factors, partly through binding to an extracellular receptor selective for glycine-extended gastrin, and partly through an intracellular mechanism.

Animals↗
PubMed1997

[Therapy outcome of patients with soft-tissue sarcoma: retrospective analysis for identifying independent prognostic factors].

The postoperative outcome of 108 patients with soft tissue sarcoma (STS) of the extremities, the retroperitoneum, or the trunk was investigated retrospectively to identify independent factors for the over all survival and local tumor control. Chi-square single factor analysis and a Cox model were used to identify independent postoperative risk factors. Single factor analysis revealed a significant correlation with negative effect on overall survival for the variables metastasis (p < 0.0001), chemotherapy (p < 0.0009), surgical procedures (0.001), tumor size > 10 cm (p < 0.003), localization (retroperitoneum, trunk) (p < 0.03), and grading (G3/G4) (p < 0.03). Local tumor control was significantly correlated with the variable tumor size > 10 cm (p < 0.01). The Cox model showed a significant negative impact on overall survival for the factors metastasis (p < 0.002), tumor size > 10 cm (p < 0.004), grading (G3/G4) (p < 0.005), and sex (male) (p < 0.008). For local tumor control the variables were age (p < 0.006), and surgical procedures (p < 0.01).

Adolescent↗
PubMed1996

Comparison of laparoscopic handsewn suture techniques for experimental small-bowel anastomoses.

Laparoscopic techniques have only rarely been applied to procedures on the small bowel. A comparison of three handsewn intracorporeal anastomoses was carried out. Thirty pigs were divided into three groups, and a different technique was used in each group (SK, single knot; RS, running suture; CL, clip suture). Half of the animals had a relaparoscopy on day 4. The duration of the procedure was recorded, and the quality of anastomotic healing was assessed by morphological, radiological, mechanical, and biochemical examinations. The animals were sacrificed on postoperative day 14. The anastomoses in the SK group took significantly longer than in the RS or CL groups. The mean duration of relaparoscopy was 28 min. Bursting pressure values and hydroxyproline concentrations were without any significant difference. The SK and CL groups showed a good alignment of the layers and the RS showed necrosis and overlying mucosa. Most complications were noted in RS. The results demonstrate that manual small-bowel anastomoses can be performed laparoscopically. Single-knot and clip sutures are reliable techniques. The ongoing development of new instruments and the three-dimensional technique will basically improve the construction of intracorporeal anastomoses.

Anastomosis, Surgical↗
PubMed1995

Expression of gastrin, gastrin/CCK-B and gastrin/CCK-C receptors in human colorectal carcinomas.

To investigate further the presence of an autocrine proliferative loop involving gastrin in colorectal carcinomas and to clarify the receptor responsible, 102 human colorectal carcinomas and 10 hepatic metastases were investigated for the expression of the genes encoding gastrin, the gastrin/CCK-B receptor and the gastrin/CCK-C receptor. Levels of RNA expression were assayed by RNase protection assay. In addition, gastrin/CCK receptors on crude membranes of tumour tissue were assayed by radioligand binding. High-affinity gastrin/CCK-B receptors were not detected in any of the carcinomas investigated, whereas in 36% low-affinity binding was observed, consistent with the expression of the gastrin/CCK-C receptor. RNase protection assay detected the RNA for the gastrin/CCK-B receptor in 11% of the carcinomas investigated, whereas the RNA for the gastrin/CCK-C receptor was demonstrated in 75% and the RNA for gastrin in 86% of the carcinomas investigated. These results confirm the recent demonstration of progastrin fragments in colorectal carcinomas. One possible explanation for progastrin expression is that such progastrin fragments may participate in an autocrine proliferative loop. The receptor involved in this loop is more likely to be the low-affinity gastrin/CCK-C receptor rather than the gastrin/CCK-B receptor, which is rarely expressed in colorectal carcinomas.

Binding, Competitive↗
PubMed1994

Radiation enteropathy.

PURPOSE: Radiation enteropathy presents a complex clinical picture which varies from case to case. Diagnosis and treatment require a thorough knowledge of the natural history of the condition and of the complications which are to be expected. PATIENTS AND METHODS: The pathogenesis, clinical picture, diagnosis and treatment of radiation damage to the gut are described. The progress of 90 patients operated on in the Chirurgische Universitätsklinik Freiburg is retrospectively evaluated. RESULTS: Haemorrhage, vomiting, diarrhoea and, occasionally, perforation are the signs of acute radiation enteropathy, which appears weeks or months after radiotherapy. Except for perforations, these can usually be treated conservatively. Chronic radiation enteropathy does not manifest itself until years after irradiation, with diarrhoea, obstruction and the development of fistulae. The acute ileus can often be relieved with decompression tubes. After localising the stenosis radiologically with a contrast medium, and improvement in the general condition, many cases require operative intervention. This usually consists of resection, the establishment of a bypass anastomosis or enterostomy. In 44% of the patients postoperative complications followed, with a mortality of 22%. The cause of the high complication rate is partly the poor general condition of the patient, and partly the radiation induced impairment in wound healing, which may lead to insufficiency of the anastomosis and the development of fistulae. CONCLUSIONS: The treatment of radiation enteropathy is a demanding task. Because of the high complication rate, it is generally wise to choose the least risky procedure.

Adult↗
PubMed1994

[The value of CEA immunoscintigraphy for diagnosis of colorectal cancer and its metastases: results of a prospective study].

The importance of the CEA-immunoscintigraphy (IS; BW 431/26 Fa Behring) for the diagnosis of colorectal carcinoma and its metastases was determined in a prospective trial including 60 patients. The results were compared with results of the ultrasound, the CT-Scan and the Angio-CT. Patients suffered from a colorectal carcinoma (15), from a local tumor recurrence after bowel resection (10), from hepatic (39) and/or extrahepatic metastases (16). In 40 patients the diagnosis was confirmed by laparotomy. Regarding the detection of hepatic metastases the sensitivity and specificity of the Angio-CT were superior to the IS (0.86 and 0.63 vs. 0.78 and 0.45). Ultrasound and Angio-CT together revealed true positive results in 89.2%. The IS did not improve this rate. Regarding the detection of extrahepatic metastases the sensitivity and the specificity of the CT were slightly superior to the IS (0.59 and 0.87 vs. 0.47 and 0.28). However, the IS increased the rate of true positive results by 18.8% (US + CT 43.7%; +IS 62.5% true positive results). Due to these results the IS is not recommended as the method of choice to detect liver metastases. But in patients unfit for diagnostic laparotomy the IS may give additional information of the extrahepatic tumor stage.

Adult↗
PubMed1993

[Perioperative risk factors in esophageal cancer: a retrospective study of independent variables].

The postoperative outcome of 127 patients with an esophageal carcinoma was investigated retrospectively, to identify independent factors for the perioperative mortality (hospital mortality). Chi-square single factor analysis was employed to test 35 independent variables, in a second analysis stepwise logistic regression was used to determine the factors correlating with the morality. In 41 patients the esophagus was resected by a thoraco-abdominal approach, in 86 by blunt dissection. The hospital mortality was 17.3%, the 30-day mortality 12.6%. Single factor analysis revealed a significant correlation with the variable smoking (p < 0.003), post-operative morbidity (p < 0.008), CEA (p < 0.02), time of operation (p < 0.02) and surgical procedures (p < 0.02). The influence of the surgeon's experience was significant. In the stepwise logistic regression the duration of operation (p < 0.0039), the surgical procedures (p < 0.016), and the units of blood (p < 0.03) were correlated with mortality. The logistic regression showed a significant increase of mortality for the thoracoabdominal approach with increasing duration of the operation. The estimation of survival time according to Kaplan and Meier revealed a significant correlation with the stage of the tumor, but not with the surgical procedure.

Adenocarcinoma↗