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B Stamm

Publications and source records attributed to B Stamm.

At least 55 records · Page 3Linked to original sources
PubMed1989

Localization of proinsulin and insulin in human insulinoma: preliminary immunohistochemical results.

We have carried out an immunohistochemical investigation of 15 human insulinomas applying monoclonal antibodies specifically recognizing proinsulin and insulin. Our results demonstrate that the epitopes unique to proinsulin and insulin can be detected with the respective monoclonal antibodies using the protein A-gold technique after routine formaldehyde fixation and paraffin embedding of the tissues. The immunostaining pattern for proinsulin and insulin in the insulinomas was different from the observed in B cells of pancreatic islets present in the adjacent normal pancreas. Furthermore, the pattern of immunostaining was found to vary from tumor to tumor. These findings strongly suggest the possibility of a disturbed proinsulin to insulin conversion in human insulinomas.

Adenoma, Islet Cell↗
PubMed1989

[Experimental pancreatic duct occlusion with polyurethane].

Pancreatic transplantation requires an effective method to manage exocrine secretion. A new technique to eliminate the exocrine function of the pancreas by obstruction of the duct with polyurethane was investigated in terms of function, outcome and morphology. Polyurethane is an alcoholic solution of block copolymers with the property of polymerizing within 5-10 min. In this study the in-situ pancreatic tail model in dogs was utilized, the pancreatic duct was cannulated and injected with 2-3 ml of polyurethane. As a result, complete atrophy and fibrosclerosis of the exocrine tissue was obtained leaving islets well vascularized and functioning for the entire experimental periods. All animals remained normoglycemic and showed normal K-values. Amylase levels were found to be maximally elevated at 24 h and returned to normal within 2 weeks after duct occlusion. Insulin, glucagon and somatostatin levels remained normal. Because of its ability to effect a complete occlusion of the pancreatic ducts with subsequent atrophy of the exocrine gland and without notable disturbance of endocrine function, we feel that polyurethane solution is superior to previously used materials for this purpose.

Animals↗
PubMed1988

Biopsy pathology of the gastrointestinal tract in human immunodeficiency virus-associated disease: a 5 year experience in Zürich.

Patients with human immunodeficiency virus (HIV)-associated disease are subject to a wide variety of unusual opportunistic infections and to the development of malignant tumours. These complications frequently manifest themselves within the gastrointestinal tract and endoscopic biopsies may contribute to their diagnosis. The results of 63 such biopsies from 28 patients are reviewed in this study. The diagnoses made included: upper gastrointestinal tract candidiasis (n = 6); cytomegalovirus infection of large intestine (n = 2); cryptosporidiosis (n = 1); spirochaetosis (n = 2); Kaposi's sarcoma (n = 4); malignant lymphoma (n = 3); and anal carcinoma (n = 2). Many of the specimens also showed inflammatory changes with no demonstrable aetiological agent. No specific pattern could be recognized for HIV infection per se.

Acquired Immunodeficiency Syndrome↗
PubMed1987

[Liver apudoma simulating cystic liver].

A 36-year-old man in otherwise good general condition and with completely normal laboratory results suffered from right upper abdominal pain. Hepatomegaly was diagnosed as due to cystic liver disease after ultrasound, computed tomography and magnetic resonance imaging. Recurrent abdominal pain continued over several months. Open liver biopsy eventually revealed trabecular-tubular carcinoma (APUDoma). Silver reaction was positive in many tumour cells. Electronmicroscopy demonstrated membrane-bound granules typical for endocrine cells. Immunohistological examinations of various hormones and of neurone-specific enolase were negative, but repeatedly measured high serum levels of pancreatic polypeptide and of beta-HCG nonetheless suggested an endocrine tumour. This case demonstrates that nonparasitic cystic changes in the liver, especially multiple ones, should have a firm diagnosis established by invasive means. Endocrine tumours can be mistaken for polycystic liver disease.

Adult↗
PubMed1987

Acinar cell cystadenocarcinoma of the pancreas.

An unusual tumor of the pancreas occurred in a 42-year-old man who presented with a gradually enlarging abdominal mass and weight loss. The mass was a 2 kg/25 cm diameter encapsulated multicystic tumor closely attached to the body and tail of the pancreas. On light microscopy it showed a predominantly tubular architecture and ultrastructurally numerous zymogen granules could be demonstrated in the tumor cells. It is therefore presumed to be of acinar cell origin. This tumor has features similar to the so-called acinar cell cystadenocarcinoma described in 1981 by Cantrell et al. Sixteen months after resection of the primary tumor a solitary liver metastasis was removed at a second operation.

Adult↗
PubMed1987

[The disseminated endocrine system of man. A contribution of pathology].

The disseminated (or diffuse) endocrine system is composed of many single cells and small groups of cells disseminated in the whole organism, capable of producing biogenic amines and polypeptide hormones. They are also called APUD cells and were first detected in the mucosa of the intestinal tract, where they occur in highest concentration. Carcinoids are tumors of disseminated endocrine cells which sometime retain their hormone-producing capacity. These hormones are key factors in the control of numerous bodily functions; some are transported by way of the bloodstream, while others probably exercise their functions only within the tissue immediately adjacent to the producing cells (paracrine function). It is an interesting fact that almost identical hormones are found within the brain and within the peripheral autonomic nervous system, where they act as neural transmitters.

APUD Cells↗
PubMed1987

[Radiation proctocolitis following gynecologic radiotherapy: an endoscopic study].

The prevalence of radiation injuries was assessed in 155 of 206 surviving patients who had had radiation therapy for carcinoma of the uterus or vagina. The patients were examined according to a standardized protocol. 51 (32.9%) exhibited endoscopic proctitis, and in 10 of them sigmoid colon was also affected. The prevalence of colitis was 31 of 66 (47%) in patients treated for carcinoma of cervix and 19 of 86 (47%) in those treated for carcinoma of corpus. 41 (80.4%) had clinical symptoms (bleeding and diarrhea in 53% each). The mean time lag between radiation therapy and beginning of symptoms was 9 months. Histology was positive in only 24 (47.1%) of 51 endoscopically documented cases of proctocolitis. There was no increase in the prevalence of radiation injury after previous surgery of any kind. Nor was higher risk found in patients with hypertension, diabetes, or congestive heart failure. However, patients with low body mass were at increased risk (p less than 0.01). There was a dose-response relationship between total dose and endoscopic proctitis (p less than 0.001). The incidence was 0% below 40 Gy, 20% at 60 Gy and 50% at 90 Gy.

Adult↗
PubMed1987

[Somatostatin-producing endocrine pancreatic tumor in Recklinghausen's neurofibromatosis. Case report and literature review].

Somatostatin-producing tumors of the pancreas were first described in 1977. In 1983 a syndrome involving multiple endocrine neoplasias (MEN) was named type III A. This syndrome consists of carcinoid of the duodenum, often producing somatostatin, and von Recklinghausen's disease (neurofibromatosis) or pheochromocytoma. The case is reported of a 62-year-old man with familial neurofibromatosis and a tumor of the head of the pancreas spreading into pars II of the duodenum. After Whipple's duodenopancreatectomy the patient exhibited no further symptoms. Immunohistochemistry served to prove the production of somatostatin and small amounts of calcitonin in the tumor.

Adenoma, Islet Cell↗
PubMed1987

[Chronic pancreatitis as a possible result of analgesic abuse].

Abuse of analgesics (AA) is a well known cause of chronic interstitial nephritis. Recently a noxious effect of AA on the pancreas has been suggested based upon case observations, and first evidence for association of AA with chronic pancreatitis was presented. In the present prospective clinical study 95 patients with chronic renal insufficiency, in 53 of them associated with AA, were investigated for evidence of chronic pancreatitis (e.g. history of pancreatitis, pancreatic calcifications, diabetes and exocrine function). The patients were divided into two groups: group A consisted of 53 patients with chronic nephropathy associated with AA, and control group B consisted of 42 patients with chronic nephropathy of other etiology. Pancreatic calcifications were observed in 5 cases of group A (10%), but in none of the patients of group B. Exocrine insufficiency was found in 2 of the 5 cases with pancreatic calcifications. Only one of the 5 patients had a history of pancreatitis in association with exocrine and endocrine insufficiency. Thus pancreatic calcifications, which are virtually pathognomonic for chronic pancreatitis, were found exclusively in the group with chronic nephropathy due to analgesic abuse. Chronic pancreatitis in this group of patients is likely to be overlooked because of the lack of clinical and laboratory evidence. The present data support our previous observations that AA may be an etiological factor in chronic calcifying pancreatitis. This first evidence for a drug-induced form of chronic pancreatitis is presented.

Adult↗
PubMed1987

Treatment of distal ulcerative colitis with beclomethasone enemas: high therapeutic efficacy without endocrine side effects. A prospective, randomized, double-blind trial.

Sixteen patients with 18 attacks of distal ulcerative colitis were treated randomly with either 0.5 mg topically administered beclomethasone dipropionate (BDP) or 5 mg betamethasone phosphate (BMT). The effect of the steroid enemas on adrenocortical function was examined by ACTH tests, which were performed before and 20 days after treatment. At completion of the trial, a marked suppression of the adrenocortical function was found in seven of eight patients treated for nine attacks with BMT but not in any patients in the BDP group (P less than 0.01). The mean posttreatment basal and stimulated plasma cortisol levels in the BMT group were significantly lower as compared with the BDP group. The overall therapeutic response assessed by score systems was comparable in the two treatment groups. It is concluded that, in the topical treatment of ulcerative colitis, BDP is preferable to BMT because it exerts an equal anti-inflammatory action without affecting adrenocortical function.

Adrenocorticotropic Hormone↗
PubMed1987

Comparative diagnostic value of the calcium-pentagastrin test versus the tolbutamide test in a patient with a somatostatinoma.

We describe a patient with a small somatostatinoma of the papilla of Vater without clinical evidence for diabetes mellitus, diarrhea, steatorrhea, or cholelithiasis, showing normal plasma basal levels for somatostatinlike immunoreactivity. The diagnosis was based on histologic and immunohistochemical analysis of tumor tissue and hypersomatostatinemia induced by the calcium-pentagastrin test. Before removal of the tumor both diagnostic tests recommended for the detection of a somatostatinoma, a tolbutamide test and a calcium-pentagastrin test, were performed. Whereas the calcium-pentagastrin test provoked a markedly elevated plasma somatostatin level in association with a depressed plasma neurotensin level, the tolbutamide test surprisingly did not. After removal of the tumor the calcium-pentagastrin test no longer induced hypersomatostatinemia. Further studies are needed to determine whether the calcium-pentagastrin test is a more reliable diagnostic test than the tolbutamide test in somatostatinomas with normal plasma basal levels.

Adenoma, Islet Cell↗
PubMed1986

Pancreatic lesions and hormonal profile of pancreatic tumors in multiple endocrine neoplasia type I. An immunocytochemical study of nine patients.

Pancreatic specimens of nine patients suffering from multiple endocrine neoplasia type I (MEN I) were investigated with regard to tumor frequency and growth pattern, islet hyperplasia and endocrine cell neoformation, immunocytochemical hormone profile of the tumors, and correlation to clinical symptoms. The majority of the 201 tumors were microadenomas (diameter less than 0.5 cm), which frequently displayed a trabecular growth pattern. Microadenomatosis was considered the most distinct feature of the MEN I pancreas. Additional larger tumors (diameter greater than 1.0 cm) were found in five patients. Whereas islet hyperplasia appears not to belong to the spectrum of the pancreatic lesions in MEN I, nesidioblastosis was occasionally observed. Immunocytochemical screening revealed that among hormone-positive tumors (approximately 80% of the tumors), pancreatic polypeptide tumors (PPomas), glucagonomas, and insulinomas were the most frequent. The high incidence of PPomas in these pancreases probably accounts for the elevated serum PP levels found in many MEN I patients. Somatostatinomas, gastrinomas, vasoactive intestinal polypeptide tumors (VIPomas), and neurotensinomas were rare. Clinically overt hyperinsulinism, observed in two patients and associated with a large insulinoma, was cured by tumor resection. Eight of nine patients presented a Zollinger-Ellison's syndrome (ZES), but only in two patients were gastrin-producing tumors found. The source of gastrin in MEN I patients with a ZES, in whom no gastrinoma could be detected, remains unclear.

Adult↗
PubMed1986

Duodenal and ampullary carcinoid tumors. A report of 12 cases with pathological characteristics, polypeptide content and relation to the MEN I syndrome and von Recklinghausen's disease (neurofibromatosis).

Twelve duodenal carcinoid tumours are presented, 4 of them located in the ampulla. Symptoms included the Zollinger-Ellison syndrome (4 patients), the carcinoid syndrome (1 patient), mechanical obstruction (3 patients), bleeding (1 patient) and abdominal pain (1 patient). Two further tumours were detected by chance. Three patients with the Zollinger-Ellison syndrome had additional endocrine tumours characteristic of the MEN I syndrome. In 2 of them the duodenal carcinoids were of very small size and were multiple. They were observed in close proximity to focal areas of endocrine cell hyperplasia. Immunohistochemical investigations showed gastrin and somatostatin to be the predominant polypeptide hormones produced by these tumours. No somatostatinoma syndrome was encountered. In half of our cases additional production of insulin, VIP or even calcitonin in smaller amounts was found. Two of our patients had cutaneous manifestations of von Recklinghausen's disease and in both of them the carcinoid was located in the ampulla. One of these patients also had a pheochromocytoma.

Adult↗
PubMed1986

Acute (nonprogressive) alcoholic pancreatitis: prospective longitudinal study of 144 patients with recurrent alcoholic pancreatitis.

Over the last 10 years, a series of 144 consecutive patients with alcoholic recurrent pancreatitis have been studied prospectively at regular intervals with particular regard to exocrine function, calcifications, pancreatographic ductal changes, and histopathology of the pancreas. Based upon the long-term course, the patients were classified into two groups; group A (n = 95), those with chronic pancreatitis (78 of them with calcifications); and group B (n = 49), those with acute (nonprogressive) pancreatitis. The duration of disease from onset was 2-19 years (median, 9.7 and 8.3 years, respectively, in group A and B). The two groups were comparable at onset of the disease in age, sex, number of episodes of pancreatitis, and number of pseudocysts. In group A, all 95 cases fulfilled the strict diagnostic criteria of chronic pancreatitis within the period of observation (e.g., progressive exocrine insufficiency and/or typical morphological changes, particularly calcifications). In group B, the exocrine function remained normal over the entire period of observation. No histologic evidence of chronic pancreatitis was detected in five of seven large pancreatic specimens. Marked to moderate ductal changes were found in 10 of 16 patients in group B (despite normal exocrine function). Our data suggest that about one third of patients of the present series with alcoholic (recurrent) pancreatitis did not progress toward chronic (progressive) pancreatitis, although some demonstrated morphological alterations (except calcifications) in association with normally preserved exocrine function (residual scars?). The pathogenetic factor(s) responsible for progression (or nonprogression) of alcoholic (recurrent) pancreatitis to chronic pancreatitis remain(s) to be elucidated.

Acute Disease↗