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M Brüwer

Publications and source records attributed to M Brüwer.

At least 19 recordsLinked to original sources
PubMed2003

[Neuroendocrine tumors of the gastroenteropancreatic system--reevaluation using the Capella classification].

INTRODUCTION: Neuroendocrine tumors of the gastroenteropancreatic system (GEP) are heterogeneous regarding hormone production, localisation and biological behaviour making the prognostic evaluation of these rare tumors difficult. Capella et al. proposed a new classification that combines for the first time both biological and prognostic characteristics. This study aimed to evaluate the prognostic value of Capella's classification in the patients treated at our hospital. METHODS: 86 from 1975-1999 surgically treated and histologically confirmed neuroendocrine tumors were retrospectively classified as benign (B), uncertain behavior (UB), low grade malignant (LG) or high grade malignant (HG) following the Capella classification. These data were correlated with the long-term outcome of the patients 8.5 (range: 1-24) years after surgery. RESULTS: 43 % of tumors were localised in the pancreas, the others were equally distributed in the remaining GEP. Most tumors were classified as B (42 %) or LG (41 %), few were UB (10 %) or HG (7 %). 61 patients survived free of disease, 25 patients died, 13 of them not tumor related. Tumor related deaths were only observed in 6 patients with inoperable LG- and 6 patients with HG-neuroendocrine tumors within 3 years after surgery. CONCLUSION: The Capella classification reliably reflects the heterogeneity and the biological behaviour of GEP-neuroendocrine tumors and can therefore be recommended for clinical use.

Adolescent↗
PubMed2002

[Rectal carcinoma in a patient with familial adenomatous polyposis coli after colectomy with ileorectal anastomosis and consecutive chemoprevention with sulindac suppositories].

Surgery is the definitive treatment in familial adenomatous polyposis coli (FAP). Proctocolectomy with ileal pouch anal anastomosis is recommended for the majority of FAP patients. Only in patients with attenuated FAP, is a colectomy with ileorectal anastomosis (IRA) accepted, although the risk for rectum carcinoma remains increased. Sulindac, a chemoprophylactic agent, regresses colorectal adenomas in patients with FAP. Under systemic Sulindac-therapy, three carcinomas in the rectum after colectomy with IRA have been described. We report the first known case of rectum carcinoma in a patient with FAP, 51 months after IRA and local Sulindac therapy.

Adenocarcinoma↗
PubMed2001

Role of appendix and spleen in experimental colitis.

There is growing clinical evidence suggesting that certain secondary lymphoid tissues (e.g., appendix and spleen) contribute to the initiation and/or perpetuation of ulcerative colitis. In this study, the importance of secondary lymphoid tissues in inducing colitis was assessed experimentally by removing the spleen and/or appendix (or sham operation) prior to inducing colitis in mice. Feeding 2.5% dextran sulphate sodium (DSS) in drinking water over 7 days induced colitis. Clinical disease activity was assessed based on weight loss, stool consistency, and presence of blood in stools. Additional measurements included white blood cell count and hematocrit, and myeloperoxidase activity (MPO) in colon samples. Colonic injury was assessed by histology and computerized image analysis. DSS treatment in sham-operated mice produced colitis associated with weight loss, bloody diarrhea, and mucosal ulceration. Clinical assessment of DSS-treated mice subjected to appendectomy or combined appendectomy/splenectomy exhibited a delayed onset and course of disease activity. Histomorphologic examination revealed significantly lower damage scores and a reduction in ulcerated mucosal surface area. Colonic MPO activity, which correlated with tissue injury and disease activity, was lowest in appendectomized mice. No beneficial effects of splenectomy were observed after 7 days of colitis. These findings support the hypothesis that appendicular lymphoid tissue, but not the spleen, contributes to the development of colitis.

Animals↗
PubMed2001

Increased expression of metallothionein in inflammatory bowel disease.

OBJECTIVE: Metallothioneins (MT) are cytoprotective against the damaging effects of oxygen-derived free radicals. Therefore MT may be involved in defence mechanisms to counter Crohn's disease (CD) and ulcerative colitis (UC). MATERIALS: 107 routinely processed tissue samples from 22 patients with CD and 48 patients with UC were tested with the monoclonal anti-MT antibody E9. METHODS: Immunohistochemistry was used to assess MT staining in a semiquantitative manner. Chi-square test was used for statistical analysis. RESULTS: MT overexpression was found in the fibroblasts of all ulcerative and/or fissural lesions in UC and CD. MT overexpression in intestinal epithelial cells of 40% of UC and CD lesions correlated significantly with the grade of inflammation. CONCLUSIONS: MT-immunoreactivity in fibroblasts supports a protective role for MT in inflammatory bowel disease. It remains unclear whether MT overexpression in epithelial cells is also important in this protection.

Humans↗
PubMed2001

[Colorectal carcinoma. Minimally invasive surgery under quality aspects--limitations].

Owing to a lack of long-term survival in prospective randomized studies controversy continues to surround the use of laparoscopic resection in cases of colorectal carcinoma. However short-term survival and recurrence rate seem to be similar to conventional procedures. Mortality and morbidity rates following laparoscopic surgery seem to be equal to conventional surgery. Oncological problems associated with laparoscopic colorectal surgery with curative intent include inadequate radicality, incorrect surgical technique, and failure to observe the technical and/or oncological limitations applicable to certain tumor sites. Carcinomas of the right and left hemicolon, colon sigmoideum and of the lower rectum without a possibility of continence preservation can be safely treated by laparoscopy. All other locations, tumors with a size greater than 8 cm and tumors involving the surrounding tissue are technically demanding and difficult to be treated laparoscopically following oncological criteria. The incidence and pathogenesis of trocar site metastases are unknown. Surgical concepts to avoid these sequelae are not established.

Colectomy↗
PubMed2000

[Intraoperative radiotherapy as multimodal therapy approach in epithelial tumors of the gastrointestinal system].

Surgery alone often fails to achieve local control in advanced gastrointestinal tumors. With multimodal therapy approaches, both local tumor control and long-term survival appear to be improved. Intraoperative radiation therapy (IORT) is an attempt to achieve higher doses of irradiation while dose-limiting structures are surgically displaced. It has been shown previously that both local tumor control and long-term survival are improved in patients undergoing surgery combined with IORT for both primary and recurrent rectal carcinoma. In advanced gastric carcinoma, IORT has achieved optimistic survival results in a few studies. In locally advanced pancreatic cancer, an apparent improvement in local control has been noted with IORT, but survival has not been prolonged because of a high incidence of both liver and peritoneal metastases. The data concerning IORT for esophageal carcinoma are not yet sufficient to allow judgement.

Animals↗
PubMed2000

[Fulminant necrotizing fasciitis secondary to Crohn's disease].

Necrotizing fasciitis is a life-threatening infection, commonly caused by group A streptococci, which has to be treated by surgical exploration and debridement during the first 24 h. Clinical clues are severe pain, in some cases followed by the appearance of bullous formations, and the detection of gas in the soft tissues by computed tomography or MRI. In addition to that, the infection is characterized by rapid inflammatory progression, producing a highly life-threatening situation. Diagnosis is finally based on surgical exploration obtaining specimens for culture and histopathologic examination. Debridement and exploration, in some cases amputation of the extremity, are indicated as soon as possible. Antibiotic therapy increases efficacy too, but there is no substitute for surgical treatment. Inflammatory bowel disease (Crohn's disease in this case) followed by necrotizing fasciitis is rarely mentioned in the literature. Therapeutic management in a situation of immunosuppression is discussed by illustration of an actual case.

Adult↗
PubMed1999

[Stoma physiology].

In addition to psychological stress, stomas may lead to metabolic consequences. Colostomies normally cause only minor physiological problems; however, patients with ileostomies are at risk for severe metabolic disturbances. The small intestine essentially manages the balance of water and electrolytes and the absorption of nutrition. In special circumstances such as "high output" or short-bowel syndrome, dangerous consequences like kidney disorders may arise. Basic therapeutic strategies such as enteral or parenteral substitution are discussed.

Colostomy↗
PubMed1999

Transepithelial transport processes at the intestinal mucosa in inflammatory bowel disease.

Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) of unknown etiology. Oral absorption studies have shown an increased intestinal permeability for various sugar molecules in patients with IBD and their healthy relatives as a possible pathogenetic factor. However, the various transport pathways through the mucosal barrier have not yet been examined. This study therefore investigated whether antigens pass the epithelial barrier by a transcellular or a paracellular pathway. Mucosa of freshly resected specimens from CD (n = 10) or UC (n = 10) patients was investigated by immunoelectron microscopy and compared with healthy mucosa. Epithelial transport was studied with the antigens ovalbumin and horseradish peroxidase after defined incubation. Labeling density of subunit c of ATP synthetase was determined in mitochondria of enterocytes of all specimens. In all specimens epithelial transport of OVA and HRP was principally transcellular through enterocytes with normal ultrastructure, although some tight junctions in CD and UC were dilated. Antigens were transported within vesicles to the basolateral membrane 2.5 min after incubation. The level of enterocytes with electron-lucent cytoplasm containing a high amount of antigens was higher in CD and UC than in healthy mucosa, depending on the grade of inflammation. ATP synthetase was significantly decreased in electron-lucent cytoplasm of CD and UC to normal ultrastructure of healthy mucosa. Our study shows that ovalbumin and horseradish peroxidase taken up by the apical membrane reach the paracellular space by vesicular transport in healthy and IBD enterocytes within a few minutes. Transcellular pathway is affected in both CD and UC, which is indicated by a high level of antigens within the cytosol. We speculate that increased intestinal permeability in IBD results substantially from enhanced transcellular transport.

Adult↗
PubMed1998

[Effect of proctocolectomy on fluid balance--comparison of conventional ileostomy, ileorectal anastomosis and ileoanal pouch operation].

Total colectomy for ulcerative colitis (UC) and familiar adenomatous polyposis coli (FAP) is mainly performed as an ileoanal Pouch procedure (IAP). Alternatives are ileorectal anastomosis (IRA) and conventional proctocolectomy with Brooke ileostomy (CPS). The different surgical techniques may influence the excretion of water and electrolytes in stool and urine and may lead to a higher risk for urolithiasis. We investigated patients (12 IAP, 12 IRA and 8 CPS) several years after surgery and compared them to twelve normal controls. Total fecal and urinary output was collected at two consecutive days. Volume and electrolytes were determined in stool and urine. The risk for urinary stone formation was calculated by nomograms. Fecal volume and sodium (Na+) excretion was increased in all therapy groups compared to controls. IAP and IRA had significant less stool volume and Na+ excretion compared to CPS. Augmented fecal Na+ excretion was compensated by reduction of renal output after colectomy compared to controls. There were no significant differences in the daily urine volume between any groups. There was no urolithiasis in any groups. The nomograms showed a risk for all groups and controls to develop urinary stones.

Adenomatous Polyposis Coli↗
PubMed1998

[Classification of neuroendocrine tumors and the effect on surgical technique].

Neuroendocrine tumors of the gastrointestinal tract are heterogenous regarding hormone production and tumor biology and have a varying disease course and survival time. In 1995 Capella et al. proposed a new classification of neuroendocrine tumors combining characteristics of the primary (i.e. histological differentiation, size, extension into surrounding tissues, hormonal activity and angioinvasion) and its suspected biological behavior (benign, uncertain, low-grade malignant, high-grade malignant). The extent of surgical therapy depends on the malignant potential of the primary tumor. To evaluate the usefulness of this classification in practical work neuroendocrine tumors have to be categorized by this classification and these data have to be correlated with the individual long-term course of patients.

Gastrointestinal Neoplasms↗
PubMed1998

[Indications for restorative proctocolectomy in systemic colorectal diseases (ulcerative colitis and familial adenomatous polyposis coli)].

Restorative proctocolectomy is now the procedure of choice for patients suffering from ulcerative colitis (UC) and familial adenomatous polyposis coli (FAP). The majority of patients with UC require surgery for failure or development of side effects of medical therapy. Other indications include dysplasia, carcinoma and complications from either medical therapy or the disease, such as massive bleeding or perforation. In the adolescent patient, resection may be necessary owing to growth retardation. In patients with FAP the 100% risk of developing colorectal carcinoma can be avoided only by proctocolectomy. Crohn's colitis and carcinoma of the lower rectum represent absolute contraindications. A relative contraindication exists in indeterminate colitis, patients with poor sphincter function, mesenteric desmoids, obesity and an age above 65 years.

Adenomatous Polyposis Coli↗
PubMed1996

[Changes in fecal bile acid excretion after proctocolectomy].

To study the effect of total colectomy for fecal bile acid excretion we examined groups of patients with ulcerative colitis and familial adenomatous polyposis coli 4,8 +/- 2.9 years after surgery. Patients after total colectomy showed a significant higher fecal bile acid excretion compared to healthy persons (mean +/- SD: 190.8 +/- 195.2 mumol/d). The highest fecal output occurred in patients with permanent ileostomies (mean +/- SD: 7595.0 +/- 5651.4 mumol/d), it was significantly higher compared to patients with ileoanal pouch anastomosis (mean +/- SD: 2212.8 +/- 2132.8 mumol/d). The daily fecal output of patients with ileorectal anastomosis (mean +/- SD: 4331.8 +/- 6314.7 mumol/d) is between the results of both other groups without any significance. After total colectomy only primary bile acids were found in each group whereas healthy people had almost identically rates of primary and secondary bile acids in their stools.

Adenomatous Polyposis Coli↗
PubMed1994

Control of human arm movements in two dimensions: paths and joint control in avoiding simple linear obstacles.

In order to examine path planning and the control of redundant degrees of freedom in the human arm, the movements of the shoulder, elbow and wrist were recorded as subjects moved a pointer to a target and avoided a simple obstacle. With respect to joint control, the results show that the extra degree of freedom provided by the wrist is incorporated into target movements in a systematic manner for both large and small obstacles; it is not used only when there is no geometrical alternative. For the wrist, two strategies are apparent, depending upon the length of the obstacle. Wrist extension predominates for shorter obstacles, while flexion or extension and flexion predominate for longer obstacles. These wrist movements shorten the effective length of the distal segments (lower arm plus hand and pointer) and thus reduce the excursion required at the proximal joints. In part, they correspond to assuming the most comfortable arm configuration at each point in the new path necessitated by the obstacle and can be described by static cost functions. However, wrist extension is also used to move the hand and pointer away from the obstacle as shoulder and elbow movements carry the wrist itself towards the obstacle. Wrist flexion is also used to move the pointer tip rapidly past the obstacle. These components, which cannot be explained by static cost functions alone, confirm for the human arm the hypothesized use of redundant degrees of freedom in obstacle avoidance. With respect to path planning, the results show that the minimum distance between pointer and obstacle remains fairly constant over a large range of obstacle lengths; this relative invariance is interpreted to support the hypothesis that workspace coordinates are important for movement planning. However, minimum distance and several other path parameters do depend significantly on the orientation and location of the movement in the workspace. This inhomogeneity implies that movement planning does not occur exclusively in workspace coordinates; it suggests an influence of joint space criteria. In frontal movements, for example, the systematic decline in the minimum distance with increasing obstacle length is interpreted as a compromise reducing the amount of extra joint movement and the discomfort of arm configurations.

Adult↗
PubMed1991

Apparent size as a function of vertical gaze direction: new tests of an old hypothesis.

The hypothesis was tested that the decline of apparent size with elevated gaze results from a latent tendency of the eyes to diverge and thus increased vergence effort. Through the use of a method of category estimation, the decline of apparent size on elevation or depression of gaze was found not to be different between subjects with larger or smaller changes of dark vergence and thus vergence effort. In a 2nd experiment, vergence effort was varied by varying gaze elevation and the angle of convergence. With vergence effort constant, apparent size was dependent on the angle of convergence rather than being constant. It is concluded that apparent size does not depend on vergence effort and that the effect of gaze elevation on apparent size cannot be attributed to its concomitant effect on dark vergence.

Adolescent↗
PubMed1991

Preferred vertical gaze direction and observation distance.

Hill and Kroemer (1986) and Kroemer and Hill (1986) found that the preferred vertical direction of gaze is lower with a nearer binocular stimulus than with a more distant one. A model is proposed that relates this phenomenon to characteristics of the resting state of the oculomotor system. Three predictions of the model were tested, based on measurements of the preferred vertical gaze direction and dark vergence in the same subject sample. On average the effect of observation distance on the preferred vertical gaze direction served to reduce the discrepancy between the resting state of vergence, operationally defined as dark vergence, and actual convergence during inspection of the binocular stimulus. Second, dark vergence data from individual subjects could be successfully used to predict whether they raised or lowered their eyes on inspection of a binocular stimulus as compared with the preferred vertical gaze direction while viewing a monocular stimulus. Finally, predictions of the size of the change of the preferred vertical gaze direction on introduction of a binocular stimulus produced only small and non-significant correlations.

Adolescent↗