Genome mapping of postzygotic hybrid necrosis in an interspecific pear population

Deleterious epistatic interactions in plant inter- and intraspecific hybrids can cause a phenomenon known as hybrid necrosis, characterized by a typical seedling phenotype whose main distinguishing features are dwarfism, tissue necrosis and in some cases lethality. Identification of the chromosome regions associated with this type of incompatibility is important not only to increase our understanding of the evolutionary diversification that led to speciation but also for breeding purposes. Development of molecular markers linked to the lethal genes will allow breeders to avoid incompatible inbred combinations that could affect the expression of important agronomic tratis co-segregating with these genes. Although hybrid necrosis has been reported in several plant taxa, including Rosaceae species, this phenomenon has not been described previously in pear. In the interspecific pear population resulting from a cross between PEAR3 (Pyrus bretschneideri × Pyrus communis) and 'Moonglow' (P. communis), we observed two types of hybrid necrosis, expressed at different stages of plant development. Using a combination of previously mapped and newly developed genetic markers, we identified three chromosome regions associated with these two types of lethality, which were genetically independent. One type resulted from a negative epistatic interaction between a locus on linkage group 5 (LG5) of PEAR3 and a locus on LG1 of 'Moonglow', while the second type was due to a gene that maps to LG2 of PEAR3 and which either acts alone or more probably interacts with another gene of unknown location inherited from 'Moonglow'.

Esophageal intramural pseudodiverticulosis: endoscopic diagnosis and therapy

Esophageal intramural pseudodiverticulosis is a rare disease that may lead to esophageal stenosis and dysphagia. The aim of the study was to evaluate the endoscopic diagnosis, treatment and clinical course of intramural pseudodiverticulosis. We retrospectively studied endoscopic criteria of intramural pseudodiverticulitis, associated diseases, and the clinical course, particularly in patients with dysphagia because of esophageal stenosis in a period from 2002 to 2012. In 23 patients, the diagnosis was made according to endoscopic criteria. As risk factors, alcohol and tobacco consumption were present in all patients. Concomitant candida infection was present in six (26%) patients. In 12 (52%) patients esophageal stenosis was present, which was localized in the upper half of the esophagus. In 11 patients bougienage has been performed with excellent improvement of the dysphagia score from 3.7 to 1.3 (P = 0.002). However, dysphagia was recurrent in four patients with need for repeated bougienage. About half of the patients with intramural pseudodiverticulosis present with stenosis of the esophagus at the time of diagnosis. In patients with proximal esophageal stenosis and a typical risk constellation, intramural pseudodiverticulosis should be suspected. Treatment of stenosis with bougienage is effective to resolve dysphagia, but repeated bougienage may be necessary.

Evaluation of alternative sites for islet transplantation in the minipig: interest and limits of the gastric submucosa

Since the introduction of glucocorticoid-free immunosuppressive regimens, islet transplantation offers a less invasive alternative to pancreas transplantation. However, complications associated with intraportal islet injection and the progressive functional decline of intrahepatic islets encourage the exploration of alternative sites. Herein we evaluated, in the minipig, the use of the gastric submucosa (GS; group 1, n = 5) for islet transplantation compared with the kidney capsule (KC; group 2, n = 5). Subsequently we attempted to improve the vascularization of the submucosal graft (group 3, n = 5) by the addition of an extracellular matrix rich in growth factors (Matrigel). One month after grafting, we evaluated transplanted islet function in vivo and in vitro. Our study showed better function of islets engrafted in the GS than in the KC (P < .05). Despite the growth factors, Matrigel did not offer a more suitable environment to further improve engraftment (group 3, P < .05). Thus, even if the liver remains the gold standard, the GS represents a potential islet engraftment site, confirming the data obtained in vitro and in the rodent. Offering easy access by endoscopy, this site could constitute an interesting alternative for experimental studies in large mammals and, eventually, for clinical application.

Effects of very long (up to 10 years) proton pump blockade on human gastric mucosa

BACKGROUND

Long-term use of proton pump inhibitors (PPI) has been reported to worsen oxyntic mucosa gastritis and the resulting gland atrophy has been considered a potential risk factor for neoplastic changes in the gastric mucosa.

AIMS

The present study examines the effect of extended continuous PPI treatment for up to 10 years on the exocrine and endocrine stomach of patients with acid-related diseases of the upper GI tract.

METHODS

Biopsies from the antral and oxyntic mucosa taken at regular time intervals were examined for gastritis, atrophy, intestinal metaplasia, Helicobacter pylori and argyrophil cells and correlated to serum gastrin levels.

RESULTS

A general amelioration of antral gastritis without relevant changes of atrophy or intestinal metaplasia, contrasted with the worsening of gastritis and gland atrophy seen in the oxyntic mucosa of reflux esophagitis (but not gastric or duodenal ulcer) patients in the presence of H. pylori infection. In association with PPI- induced hypergastrinemia, argyrophil cell hyperplasia (but not dysplasia or neoplasia) developed in the oxyntic mucosa.

CONCLUSION

The present results outline the milder pretreatment pattern and higher proneness to PPI-related, H. pylori-restricted worsening of oxyntic mucosa gastritis in reflux esophagitis compared to gastric ulcer or duodenal ulcer patients. In addition, they confirm a substantial safety of long-term PPI therapy as concerns neoplastic changes in the exocrine and endocrine human stomach.

Pancreatic neuroendocrine tumor with extensive vascularisation and parathyroid hormone-related protein (PTHrP)--associated hypercalcemia of malignancy

We report the case of a 34 year old male presenting with symptomatic hypercalcemia due to excessive PTHrP secretion from a pancreatic neuroendocrine carcinoma with extensive hypervascularization and without any evidence for metastatic disease. In the early phase of the disease conventional chemotherapy with streptozocin and doxorubicin was able to control functional activity as well as tumor growth. However, after 2 years tumor escape was indicated by severe therapy-resistant hypercalcemia. Therapeutic options were reduced due to the excessive tumor vascularization and the patient died from his disease after a short period of intensified therapy. The role of PTHrP in hypercalcemia of malignancy (HHM) and its association with neuroendocrine pancreatic tumors as well as possible therapeutic options are reviewed.

Renin producing neuroendocrine pancreatic carcinoma--a case report and review of the literature

A 44 year old male patient presented with severe hypertension. The diagnostic work-up revealed elevated levels of plasma renin activity (about 10 times the upper limit of normal) in the presence of normal plasma aldosterone levels and serum potassium concentrations. Renovascular disease was excluded by angiography. Selective renal vein sampling did not show any renin gradient. CT-scans of the abdomen demonstrated normal morphology of the kidneys and adrenals but revealed a big mass in the pancreatic corpus and tail with infiltration of the splenic vein and the presence of enlarged local lymph nodes. The endocrine nature of the pancreatic mass was further supported by a positive octreotide scintigraphy scan. Surgical removal of the tumor by left sided pancreatectomy combined with splenectomy resulted in rapid normalization of elevated renin concentrations as well as blood pressure. Histological examination of the tumor tissue revealed the presence of a neuroendocrine pancreatic carcinoma. Highly (x 70) elevated renin levels were detected by radioimmunoassay in the tumor tissue. To our knowledge this is the first renin-producing neuroendocrine pancreatic carcinoma described in the literature. The present paper describes the case in detail and reviews the available literature on clinical symptomatology, diagnosis and treatment of renin-producing tumors.

Intestinal obstruction, progressive weight loss, and recurrent fever in two patients with mesenteric lesions

We describe 2 patients who presented with fever and incomplete intestinal obstruction. Previously, both patients had had laparotomies showing unresectable lesions in the root of the mesentery which were histologically diagnosed as sclerosing mesenteritis in the first and mesenteric fibromatosis in the second patient. In spite of aggressive immunosuppressive therapy the first patient deteriorated with high-grade fever and progressive weight loss. Similar symptoms occurred in the second patient. Computed tomographic scanning revealed necrotic lesions in both patients which histologically were found to be an angiocentric T-cell lymphoma in the first and a superinfected necrotizing fibroma in the second patient. It is therefore clinically and radiologically impossible to distinguish between the different causes of mesenteric lesions. Reoperation for further biopsies needs to be considered if such patients do not respond to medical treatment.

Morphological changes of the human gastric mucosa under long-term proton pump inhibitor therapy and their clinical relevance

Proton pump inhibitors are potent drugs for the treatment of acid-related diseases. The moderate hypergastrinaemia observed during therapy is a physiological response to low intragastric pH and the increase is limited to the first months of therapy with no further changes thereafter. Reports on endocrine cell changes in the antral mucosa under chronic PPI therapy are controversial and lack clinical relevance. In contrast, in the oxyntic mucosa hyperplastic argyrophil cell changes have been reported, dependent on the degree and duration of hypergastrinaemia, the severity of oxyntic mucosal gastritis, especially atrophy, and the presence of H. pylori infection. Current data do not support a progression from hyperplastic to dysplastic argyrophil cell lesions in humans in the absence of additional genetic factors. Data on the progression of oxyntic gastritis under chronic PPI treatment in comparison to untreated controls could not be confirmed in more recent studies including a well-matched control population. The main factor for gastritis progression is the presence of Helicobacter pylori infection. The bacterium not only causes a chronic inflammation of the gastric mucosa, resulting in atrophy and intestinal metaplasia, but also influences endocrine cell populations involved in the regulation of gastric acid secretion. The clinical benefit of H. pylori eradication in reflux esophagitis patients is still a matter of debate. The complex relations in humans between hypergastrinaemia, (oxyntic) gastritis and atrophy, H. pylori infection, argyrophil cell hyperplasia, and the effects of long-term PPI treatment of acid-related diseases do not allow a quantification of the contribution of each single factor for the observed changes.

Morphological changes of the human gastric mucosa under long-term proton pump inhibitor therapy and their clinical relevance

Proton pump inhibitors are potent drugs for the treatment of acid-related diseases. The moderate hypergastrinaemia observed during therapy is a physiological response to low intragastric pH and the increase is limited to the first months of therapy with no further changes thereafter. Reports on endocrine cell changes in the antral mucosa under chronic PPI therapy are controversial and lack clinical relevance. In contrast, in the oxyntic mucosa hyperplastic argyrophil cell changes have been reported, dependent on the degree and duration of hypergastrinaemia, the severity of oxyntic mucosal gastritis, especially atrophy, and the presence of H. pylori infection. Current data do not support a progression from hyperplastic to dysplastic argyrophil cell lesions in humans in the absence of additional genetic factors. Data on the progression of oxyntic gastritis under chronic PPI treatment in comparison to untreated controls could not be confirmed in more recent studies including a well-matched control population. The main factor for gastritis progression is the presence of Helicobacter pylori infection. The bacterium not only causes a chronic inflammation of the gastric mucosa, resulting in atrophy and intestinal metaplasia, but also influences endocrine cell populations involved in the regulation of gastric acid secretion. The clinical benefit of H. pylori eradication in reflux esophagitis patients is still a matter of debate. The complex relations in humans between hypergastrinaemia, (oxyntic) gastritis and atrophy, H. pylori infection, argyrophil cell hyperplasia, and the effects of long-term PPI treatment of acid-related diseases do not allow a quantification of the contribution of each single factor for the observed changes.

[Initial manifestation of primary intestinal lymphangiectasis as acute abdomen]

HISTORY

A 32-year-old man had ten years previously undergone several laparotomies for recurrent ileus of the small intestine. They revealed severe intestinal oedema and histology showed hyperplasia of the lymphatic system but the aetiology was unclear. After a 10-year interval free of symptoms he presented with marked hypoproteinaemic oedema and exudative enteropathy the cause of which was to be clarified by exploratory laparotomy with excision of lymph nodes and a small section of small intestine.

INVESTIGATIONS

Histology revealed intestinal lymphangiectasis with partly hyperplastic lymphoid tissue. Lymphangiography demonstrated several lymph nodes in the region of the aortic bifurcation and renal vessels with a central filling defect. It is thought likely that obstruction to lymphatic flow in this region resulted in oedema of the intestinal wall which caused the recurrent episodes of ileus.

DIAGNOSIS

Retrospectively it is assumed that primary intestinal lymphangiectasis was responsible for the initial manifestation of an acute abdomen. For treatment of hypoproteiaemia with human albuminea prot system was implanted. The course was complicated by recurrent inflammation and thrombosis of the port catheter. Because of immune deficiency risk of carcinoma is high in primary intestinal lymphangiectasis.

CONCLUSION

Primary intestinal lymphangiectasis, even though a rare condition, should be considered in the differential diagnosis of otherwise unclear acute abdomen.

[Multiple endocrine neoplasia Type I. Diagnosis and therapy in a case with classical family history]

BACKGROUND

A classical family history, representative of the multiple endocrine neoplasia type I (MEN I) syndrome, is reported to illustrate the clinical manifestations, diagnostic procedures and therapeutic modalities of the various endocrine disorders of this syndrome.

DIAGNOSIS

Today genetic analysis clearly identifies gene carriers. In these patients screening of all involved endocrine organs (parathyroid, pituitary, pancreas) at regular time intervals is necessary because also at higher ages additional endocrine manifestations may develop. Due to consequent screening the age at time of diagnosis was reduced by 10 to 20 years. As a consequence the rate of malignancy of pancreatic endocrine tumors which is the limiting factor with regard to long-term prognosis was reduced to about one third. At present it is not known whether this procedure can also increase the survival rate of MEN I patients as could be demonstrated in the MEN II syndrome.

Role of circulating gastrin in colorectal adenomas and carcinomas

BACKGROUND/AIMS

A trophic role of gastrin has been convincingly demonstrated in the oxyntic mucosa of the stomach, but is still a matter of debate in the lower gastrointestinal tract.

METHODS

In order to examine the role of circulating gastrin in colorectal adenoma and carcinoma fasting serum gastrin concentrations were determined in 351 patients undergoing complete colonoscopy.

RESULTS

In comparison to controls (n = 145) more patients with either polyps (n = 125) or colorectal carcinoma (n = 81) have slightly increased serum gastrin concentrations, leading to an increased mean, but no change in median serum gastrin levels. In 3 patients preoperatively increased serum gastrin concentrations were normalized after surgical removal of the polyp and/or tumor, suggesting a local release of gastrin from the polyp/tumor. Gastrin concentrations do not correlate with the histopathological classification or malignant potential of adenomatous polyps.

CONCLUSION

In view of these findings a significant role of circulating endogenous gastrin in human colorectal carcinogenesis seems to be unlikely.

Electron-microscopical evidence for heterogeneity of micronodular argyrophil cell growth in man

Hypergastrinaemia-associated changes of non-antral argyrophil cells in man are of increasing interest, because of the development of potent inhibitors of gastric acid secretion. Using an antibody against chromogranin A, we identified micronodular endocrine cell hyperplasia of the oxyntic mucosa in gastric biopsy specimens of patients with hypergastrinaemia of different backgrounds. Consecutive ultrathin sections were examined at the electron-microscopical level. Endocrine cell types within the (extraepithelial) micronodules closely resembled those in the adjacent mucosa. Micronodules were classified into two groups. The first group was composed of endocrine cells only and predominated in patients with drug-induced hypergastrinaemia and/or chronic gastritis, and in a gastrinoma/MEN I patient. The second group represented "neuroendocrine complexes", showing a close intermingling of non-myelinated nerve fibres with endocrine cells, and was found predominantly in pernicious anaemia. Micronodular argyrophil cell growth in man is therefore heterogeneous and depends on the background of the hypergastrinaemia.

Progression and prognosis of Crohn's colitis

BACKGROUND

Inflammation refractory to medical treatment frequently characterizes the course of Crohn's colitis, often leading to colectomy and need for a stoma. The influence of disease extent within the colon on prognosis and disease progress over time has not been studied so far.

AIMS

We evaluated the disease progress and the long-term outcome in 323 patients with Crohn's colitis followed-up for a mean of 9.8 years.

METHODS

The charts were analyzed retrospectively, the mean number of documented examinations was 18.5 per patient. The influence of disease pattern, rectal disease and perianal fistulas on the long-term outcome was evaluated using actuarial methods and independent factor analysis.

RESULTS

The probabilities of having pancolitis or rectal disease were 77.1% and 78.8% after 15 years, respectively, and higher in patients with initially left-sided or segmental colitis compared with right-sided colitis. The chance of having perianal fistulas was 43.3% after 15 years. The risk of undergoing resectional colonic surgery was 62.2% after 15 years and higher in the presence of right-sided colitis. The cumulative risk of colectomy was 18.2% after 15 years and higher in patients with pancolitis, left-sided colitis or in the presence of perianal fistulas. The 15-year probabilities of proctectomy (12%) and of having a temporary stoma (21%) were only influenced by the presence of perianal fistulas but not by rectal disease or pattern of colitis.

CONCLUSIONS

Most patients with colonic Crohn's disease will eventually have pancolitis but only 20% of them will loose the colon. The proctectomy rate is low despite a high frequency of rectal disease. Perianal fistulas and the presence of total or left-sided colonic involvement are adverse risk factors with regard to preservation of colonic length.

[Pheochromocytoma-induced multiorgan failure. An internal medicine and surgical emergency]

HISTORY AND CLINICAL FINDINGS

A 66-year-old woman, for 18 months known to have a phaeochromocytoma of the left adrenal, developed sciatica-like pain, headaches, vomiting, diarrhoea and dyspnoea. She had previously refused operative treatment. Physical examination was largely negative. But within a few hours of admission she developed a fever (40.5 degrees C) as well as cardiopulmonary and renal failure. She had to be intubated.

INVESTIGATIONS

There was leukocytosis (20,800/microliters) and an increase in creatine kinase activity (136 U/l), in the proportion of isoenzyme CKMB (19 U/l) and the creatine level (1.5 mg/dl). Coronary angiography excluded coronary heart disease. Compared with previous x-rays there was a definite increase in the space-occupying process in the area of the left adrenal.

TREATMENT AND COURSE

The life-threatening state required emergency removal of the adrenal tumour. The operation was without complications, but muscle weakness set in, especially proximally, and was slow to regress. No cause was found.

CONCLUSIONS

Primary manifestation of a phaeochromocytoma in the form of multiple organ failure is rare and its diagnosis is based on symptoms and radiological demonstration of the tumour, because biochemical data are obscured by the need to give catecholamines therapeutically. If the general condition deteriorates during conservative treatment immediate removal of the tumour is mandatory in view of the otherwise high death rate.

[Hormone dependence of colorectal carcinomas]

The question of a possible hormonal control of colorectal cancer growth can be examined by several different approaches. At the present time epidemiological studies do not give a conclusive answer to this problem. The demonstration of functionally active peptide hormone receptors on colon cancer cell lines may play a role in a subgroup of receptor-positive tumors only. At the present time a classical endocrine mode of action of peptide hormones can be excluded. However, there is a possibility of a "hormonal control" of colorectal carcinomas by so-called "growth factors". In this system the expression of a stimulating growth factor, the demonstration of a specific receptor, the blocking of the effect by receptor antagonists or growth factor antibodies and the demonstration of a functional activity have been fulfilled. The multiple relations between cellular protooncogenes and growth factors on the level of the ligand itself, the receptors, or the intracellular signal transduction connect the process of malignant transformation with hormonal control of growth regulation. This connection might offer a basis for a more causal therapy of colon carcinomas within the near future.

Long-term omeprazole therapy in peptic ulcer disease: gastrin, endocrine cell growth, and gastritis

BACKGROUND

The effects of chronic drug-induced hypergastrinemia on the exocrine and endocrine stomach are still incompletely understood. Chronic hypergastrinemia in rats and humans is associated with gastric argyrophil cell hyperplasia.

METHODS

Seventy-four patients with chronic ranitidine-resistant ulcerations were treated chronically with omeprazole (median observation period 48 [6-84] months).

RESULTS

Median fasting serum gastrin levels increased from a pretreatment value of 74-145 pg/mL after 3 months. No further increase was observed thereafter. The finding of atrophic gastritis increased from 1.8% to 20.8% after 5 years. A doubling of the mean argyrophil cell volume density (0.36% vs. 0.74% after 5 years; P < 0.01%) was paralleled by a decrease in the normal endocrine cell growth pattern from 64.3% to 33.3% and an increase in micronodular hyperplasia (8.9% vs. 16.7%). These changes correlated with the severity of corpus gastritis and seemed to be more disease- than drug-related. No statistically significant changes were observed in the antral G- and D-cell volume densities under therapy.

CONCLUSIONS

Long-term omeprazole therapy in humans results in moderate hypergastrinemia and a significant argyrophil cell hyperplasia, which are correlated to the grade of corpus gastritis. Because hypergastrinemia and gastritis are closely related, it is difficult to quantitatively assess their respective role in this process.

[Type-2B multiple endocrine neoplasms with diffuse liver metastases as the cause of chronic diarrhea]

During examination before surgical correction of pes valgus a 20-year-old man reported having 3-5 pasty, foul smelling diarrhoeic motions per day for the past 3 years. He was noted to have rather thick lips and Marfan-like body build. Erythrocyte sedimentation rate was 18/34 mm, serum activity of GOT 22.5 U/l, GPT 35.7 U/l. Faecal weight was increased to 640 g/d, fat content to 12 g/d. Serum levels of the carcinoembryonic antigen (2494 ng/ml; normal: < 2.5) and of calcitonin (1,619,760 pg/ml; normal < 100) were elevated. Gastroscopy, partial coloscopy, colon-contrast imaging, ultrasonography and computed tomography of the neck and abdomen, as well as magnetic nuclear imaging of the neck were all normal. But laparoscopy revealed the liver to be infiltrated by small whitish nodules which immunohistologically proved to be metastases of a C-cell carcinoma. Total thyroidectomy was performed and the diagnosis of a C-cell carcinoma of the thyroid confirmed intra-operatively. After the operation the diarrhoea was stopped with codeine (9 mg/d). In case of tumour progression, therapy with octreotide, a somatostatin analogue, will be carried out. The concomitant occurrence of C-cell carcinoma, Marfan-like body build, thick lips and skeletal changes is typical of multiple endocrine neoplasia type 2B, which is caused by a chromosomal defect.

Budd-Chiari syndrome as the primary manifestation of a fibrolamellar hepatocellular carcinoma

An 18-year-old female patient was admitted with ascites, right upper abdominal tenderness and peripheral edema. Angiography showed complete occlusion of the vena cava inferior up to the level of the right atrium. By open heart surgery, masses of thrombotic material were pulled out of the v. cava inferior/vv. iliacae which histologically contained tumor cell populations consistent with a hepatocellular carcinoma. Celiacography showed a highly vascularized tumor in the right hepatic lobe. Histologically, it proved to be fibrolamellar subtype hepatocellular carcinoma.

Inter-relationship between serum gastrin levels, gastric mucosal histology and gastric endocrine cell growth

The development of gastric enterochromaffin-like (ECL)-cell hyperplasia in humans may be associated with extreme hypergastrinaemia, as occurs in Zollinger-Ellison syndrome (ZES) and pernicious anaemia (type A gastritis). More recently, endocrine cell hyperplasia has been found in all forms of chronic atrophic gastritis and even in cases of focal atrophy. Serum gastrin levels, non-antral gastric endocrine (argyrophil) cell growth, and the severity and type of concomitant gastritis were monitored in 66 unoperated and 8 antrectomized patients with poorly responsive peptic ulcer or reflux oesophagitis during up to 5 years' treatment with high-dose omeprazole, 40 mg daily. A small subgroup of patients (23%) had serum gastrin concentrations of more than four times the normal upper limit. These patients also had hyperplasia of the gastric argyrophil cells. More importantly, the same subgroup of patients had high-grade (atrophic) gastritis. Micronodular hyperplasia of argyrophil cells was significantly more frequent in biopsies showing atrophic gastritis (48%) than in biopsies showing only superficial gastritis (3.6%). It is concluded that, as previously demonstrated in untreated patients with gastric ulcer, the argyrophil cell hyperplasia observed during high-dose omeprazole therapy is related to the progression of chronic atrophic gastritis rather than to serum gastrin levels.

Lysosomal storage of glycogen as a sequel of alpha-glucosidase inhibition by the absorbed deoxynojirimycin derivative emiglitate (BAYo1248). A drug-induced pattern of hepatic glycogen storage mimicking Pompe's disease (glycogenosis type II)

Effects of the two absorbable alpha-glucosidase inhibitors miglitol (BAYm1099) and emiglitate (BAYo1248) on hepatic and muscular glycogen concentrations were investigated in the rat after 3, 7, and 28 days. Both compounds were (orally) administered at very high doses (5-50-500 mg/kg b.wt.). In a second experiment, glycogen storage after oral administration of acarbose (1000 mg/kg b.wt.) was studied after 7 days. In a third protocol, hepatic glycogen concentrations were investigated in the fed rat after 7 days of either inhibitor at the respective highest dosage. In fasted rats, emiglitate induced a significant, dose-dependent increase of hepatic glycogen concentrations, which--at the dose of 500 mg/kg b.wt.--were present after 3, 7, and 28 days, but resulted in a significant increase of the liver weight after 28 days only. Light and electron microscopy proved that the increase in hepatic glycogen was due to lysosomal storage of glycogen only. Emiglitate in the amount of 5 mg/kg b.wt. did not induce significant changes either of glycogen concentrations or at the EM-level. While emiglitate also increased hepatic glycogen at a dosage of 50 mg/kg b.wt., miglitol led to significant storage of hepatic glycogen after 3, 7, or 28 days at the highest dose only. With miglitol (500 mg/kg b.wt.), only insignificant lysosomal storage of glycogen could be detected by electron and light microscopy, and liver weight was essentially unaffected. Both compounds displayed a dose-dependent tendency towards higher glycogen concentrations in the soleus muscle, which was significant with the highest dosage of either inhibitor. At an oral dose of o.i.d. 1000 mg/kg b.wt., the almost unabsorbable alpha-glucosidase inhibitor acarbose induced significantly increased glycogen concentrations both in the liver and in the soleus muscle after 7 days. With respect to an enormous enlargement of the lysosomes (EM) and in the absence of cytoplasmatic alpha-glycogen, this accumulation of glycogen must be attributed to lysosomal storage. In fed rats, all alpha-glucosidase inhibitors investigated significantly decreased postprandial hepatic glycogen concentrations (emiglitate greater than miglitol greater than acarbose), thereby reflecting the modulation of absorption. It is concluded that in the rat acarbose at approximately 1000 x ED50 may penetrate the intestinal mucosa at amounts significant enough to induce lysosomal storage of glycogen. Miglitol may cause some hepatocellular, lysosomal glycogen storage at a dose of 500 mg/kg b.wt., but no glycogen storage could be proven up to 100 x ED50 over 28 days.(ABSTRACT TRUNCATED AT 400 WORDS)

Somatostatin cells in rat antral mucosa: qualitative and quantitative ultrastructural analyses in different states of gastric acid secretion

In the gastrointestinal tract somatostatin is localized in endocrine cells and in neurons. The antral somatostatin (D-) cell shares features of both cell types. The activity of the antral D-cell is regulated by intragastric pH. Therefore different states of gastric acidity were induced experimentally in order to study D-cell morphology at the electron microscopical level. The morphological findings were related to measurements of plasma and tissue concentrations of the peptide. The D-cell is characterized by extensive membrane interdigitations with neighbouring cells. Changes in the activity of antral D-cells are reflected by an increase in cytoplasmic secretory granule density and a shift of secretory granules towards basal cell processes. Direct endocrine cell contacts at the level of the perikarya were rarely observed. The intracellular distribution of secretory granules suggests that cell communication is more likely to take place at the level of the strongly immunoreactive cytoplasmic processes. No evidence for endocrine or exocrine (luminar) secretion was observed morphologically. This is in agreement with the concept of paracrine secretion of the antral D-cell.

Is hypergastrinaemia dangerous to man?

Achlorhydria has been discussed as a possibly dangerous consequence of therapeutic inhibition of gastric acid secretion since the introduction of H2-receptor antagonists. The risk of long-term hypergastrinaemia has only been considered for about 5 years. The reason for this was the demonstration that gastric carcinoids (ECLomas) observed after life-long treatment of rats with the proton pump inhibitor omeprazole could also be produced in rats by other methods leading to long-lasting profound hypergastrinaemia. Such methods were the 80% resection of the oxyntic mucosa or feeding of ranitidine (2000 mg/day) for 2 years. The endocrine tumours corresponded to the gastric carcinoids found in patients with long-lasting hypergastrinaemia due to pernicious anaemia or with a gastrinoma as part of the MEN I syndrome. Neither in animals nor in man could other endocrine tumours or adenocarcinomas of the gastrointestinal tract be related to hypergastrinaemia. Epidemiologic data do not support gastrin dependence of adenocarcinoma of the stomach or the colon. Experimental findings of gastrin effects on tumour growth in vivo and in vitro have been contradictory and may be explained by the presence of gastrin receptors on tumour cells and the role of gastrin as an autocrine growth factor in some of these tumours. Since acid blockade by proton pump inhibitors or H2-receptor blockers dose-dependently increase serum gastrin levels, patients with ranitidine-resistant peptic ulceration receiving long-term treatment with high-dose omeprazole have been followed up with serial gastric biopsy specimens for up to 5 years. Complete healing, moderate hypergastrinaemia, and a slight hyperplasia but no dysplasia of the ECL cells in the oxyntic mucosa have been observed, which seemed to be correlated to chronic gastritis progressing over the years. Despite these negative findings excessive hypergastrinaemia by overdosage of potent drugs for inhibition of gastric secretion should be avoided and monitoring of plasma gastrin levels is recommended in case of long-term treatment.

Antral Helicobacter pylori-like organisms in different states of gastric acid secretion

The frequency of Helicobacter pylori (H.p.) infestation in antral mucosa and the presence of gastritis were investigated in different states of gastric acid secretion. Biopsies were stained by the Warthin-Starry technique and hematoxylin-eosin. Antral H.p. was found in similar frequencies in Zollinger-Ellison syndrome (n = 17; profound acid hypersecretion, associated with duodenal ulcer disease in most cases) and the same number of age-matched controls (35% in each group) whereas H.p. could be detected in 31 out of 33 duodenal ulcer patients (94%). The incidence of H.p. infestation in H2-blocker refractory reflux oesophagitis was low (24%). Treatment of peptic lesions with omeprazole (drug-induced hypochlorhydria) led to a reduction or disappearance of H.p. in 7 out of 10 H.p.-positive patients whereas none of 19 primarily H.p.-negative patients became infected with H.p. during prolonged omeprazole therapy. It is concluded that (1) development of duodenal ulcers (as in gastrinomas) does not necessarily require H.p., and (2) at least in some patients H.p. is reduced in antral mucosa by omeprazole.

[Infectious mononucleosis: hemolysis by autoantibodies against triosephosphate isomerase]

Generalized adenopathy and splenomegaly developed in an 18-year-old youth after a severe tonsillitis followed by headache, tiredness and weight loss for several weeks. Infectious mononucleosis (acute Epstein-Barr virus infection) was confirmed by the demonstration of virus-specific antibodies. A reticulocytosis (24%), decreased haptoglobin concentration (0.6 mg/dl) and increased lactate dehydrogenase activity (657 U/l) indicated marked haemolysis. The bone marrow showed increased erythropoiesis with abnormal maturation. Antibodies against triosephosphate isomerase and against blood group marker "i" were demonstrated in the patient's serum. Antibodies against triosephosphate isomerase from the patient's serum were purified by affinity-chromatography. They strongly reacted with the patient's erythrocytes and under complement activation induced an increased 51Cr liberation from marked erythrocytes. No corresponding effect of anti-i-antibodies was noted at 37 degrees C. With the fall in antibodies against triosephosphate isomerase the haemolysis receded and the patient became free of symptoms after 7 weeks.

Light and electron microscopical immunocytochemical localization of pancreastatin-like immunoreactivity in porcine tissues

Pancreastatin is a 49 amino acid comprising peptide isolated from porcine pancreas that is derived by proteolytic processing from chromogranin A. Using an antibody against the synthetic C-terminal fragment pancreastatin (33-49), we examined the light and electron microscopical immunocytochemical localization of this peptide in porcine tissues. Pancreastatin-like immunoreactivity (PLI) was found in pancreatic somatostatin-, insulin- and glucagon cells in varying intensities; pancreatic polypeptide cells were always negative. At the electron microscopical (EM) level the immunoreactivity was confined to the electron dense core of the secretory granules in the case of somatostatin and insulin cells or to the less electron dense "halo" of the glucagon granules. In the antrum PLI positive cells represented gastrin (G), somatostatin (D) and enterochromaffin (EC) cells, in the duodenum in addition to EC- and G-cells a small number of PLI positive cells showed a positive immunoreaction for glucagon-like peptide (GLP) I and secretin in serial sections. Both norepinephrine and epinephrine containing cells of the adrenal medulla exhibited a strong reaction for PLI. In the pituitary several cell populations stained with varying intensities, including gonadotrophs and thyrotrophys. PLI is present in a distinct and characteristic subpopulation of neuroendocrine cells in various organs. The subcellular localization may indicate a function in the granular concentration, packaging and storage of peptides and amines in the brain-gut endocrine system.

Investigation of the origin of the impedance cardiogram by means of exchange transfusion with stroma free haemoglobin solution in the dog

PURPOSE OF INVESTIGATION - To determine the contribution of variations in orientation of erythrocytes (orientation effect) to the heart synchronous variations in thoracic impedance in impedance cardiography. DESIGN - The blood of four dogs was gradually replaced by stroma free haemoglobin solution, causing a decrease in resistivity and orientation effect. The decrease in orientation effect was used to determine the contribution of the orientation effect using an extended form of the "parallel conductor" model of the thorax (parallel connection of a tissue admittance Yt and a blood conductance Gb). SUBJECTS - Four adult splenectomised mongrel dogs. MEASUREMENTS and RESULTS - Packed cell volume and resistivity at body temperature of every volume of circulating fluid removed was measured. Real and imaginary parts of the transthoracic impedance and the modulus of the heart synchronous impedance variations were measured just before each exchange. The parallel conductor model was extended to account for the influence on Gb of packed cell volume and orientation of erythrocytes. Applying this extended model, the average variations in Gb at a packed cell volume of 40% were estimated to be 7.46%:3.03% due to volume variations, 4.43% due to orientation effect. After further extending the model to account for the influence of small changes in blood pressure and heart rate, the average volume variations were estimated to range from 2.8% to 3.3% and the average orientation effect from 4.1% to 4.7% at a packed cell volume of 40%. CONCLUSION - Resistivity of the blood is far from constant and the contributions of variations in blood conductivity and volume to the heart synchronous thoracic impedance are of comparable magnitude. The contribution of the volume variations is the sum of the volume variations in the contributing intrathoracic vessels. The effects of variations in orientation are added up in proportion to the relative volumes of the contributing vessels. The extensions of the parallel conductor model brought out all physiological factors determining the heart synchronous thoracic impedance variations: pulse pressures and flows, mean pressures and flows, compliances of all contributing blood vessels, packed cell volume and heart rate, as well as the relevant properties of blood: the relations between volume, flow and orientation effect and the change in orientation effect during decelerating flow.

Efficacy and safety of omeprazole in the long-term treatment of peptic ulcer and reflux oesophagitis resistant to ranitidine

A total of 143 patients with peptic ulceration of the duodenum, stomach and oesophagus who did not respond to 3 or more months of high-dose treatment with ranitidine, 450 mg or more daily, were treated with oral omeprazole, 40 mg daily. In 94% of the patients, ulcers healed within 2-8 weeks. After healing, 133 patients underwent long-term maintenance treatment with omeprazole, 40 mg daily, for 1-5 years (continuing). During maintenance therapy with omeprazole, no endoscopically verified relapses occurred, and no drug-related adverse effects were seen. There were no significant changes in routine laboratory tests in any patient, including 27 with concomitant liver cirrhosis. Basal serum gastrin levels, which were already elevated by the previous high-dose ranitidine treatment, rose to 4 times normal levels after 4 months of treatment with omeprazole. Thereafter, no further increases in basal serum gastrin levels were observed, even after 5 years of administration. The volume density of argyrophilic cells in the oxyntic mucosa increased during omeprazole treatment, but no dysplasia of the gastric enterochromaffin-like cells was seen. In conclusion, omeprazole was highly effective in healing ranitidine-resistant peptic ulcers, and subsequent maintenance therapy with omeprazole, 40 mg daily, was found to be effective and safe over the period observed.

[Relapsing polychondritis]

For three months a 17-year-old boy had been suffering from laryngitis, pharyngitis and conjunctivitis, weight loss, nocturnal sweating and signs of changing cranial-nerve involvement (dizziness, nausea, nystagmus). The diagnosis of recurrent polychondritis was made only when, in addition to a definite inspiratory stridor there also developed a painful swelling of the left ear cartilage and a saddle nose due to loss of the cartilaginous portion of the nasal skeleton. Histological examination of the inflamed ear cartilage confirmed the diagnosis. After treatment with prednisone (100 mg daily, gradually reduced to 25 mg) and azathioprine (100 mg daily, increased to 150 mg after three weeks), there was clinical improvement, but the airway resistance (R = 6.2 cm H2O.s/l) rose further, requiring tracheostoma twelve months after onset of symptoms.

Quantitative studies of gastric endocrine cells in patients receiving long-term treatment with omeprazole

A total of 36 patients with chronic gastric or oesophageal peptic ulceration (including 6 with antrectomy), resistant to high-dose ranitidine treatment for at least 3 months, were successfully treated with omeprazole 20-60 mg/day, for periods up to 3 years. Fasting serum gastrin levels were monitored at regular intervals during therapy and multiple gastric mucosal biopsies were taken during gastroscopy every 3-6 months. Gastrin levels increased significantly during the first 6 months of therapy from a mean of 81.5 to 206 pg/ml; a slight decrease was observed thereafter. There was no significant increase in the volume density of argyrophilic cells in the oxyntic mucosa. No clusters of endocrine cells were found in the oxyntic mucosa and no change of G-cell volume density occurred in the antral mucosa under therapy. Omeprazole therapy did not result in any changes in gastrin levels or oxyntic argyrophilic cells in the antrectomized patients. It is concluded that the moderate hypergastrinaemia observed during long-term omeprazole treatment in man does not induce hyperplasia of argyrophilic cells in the oxyntic mucosa.