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H Dancygier

Publications and source records attributed to H Dancygier.

At least 55 records · Page 3Linked to original sources
PubMed1992

[Endosonography in malignant extrahepatic obstructive jaundice].

34 patients with obstructive jaundice were investigated consecutively by transcutaneous ultrasonography, endoscopic sonography and endoscopic retrograde cholangio-pancreatography (ERCP). In 20 cases obstruction was due to a tumor, whose location and extent could be visualized by endosonography and ERCP in all cases. By transcutaneous ultrasonography this was possible in only 14 (70%) and 17 (85%) cases respectively. In seven of eight cases the tumor size, in four of five cases metastatic involvement of lymph nodes and in all cases infiltration into neighboring organs or vessels were correctly predicted by endosonography. Both other methods failed in this regard. We therefore conclude that the diagnostic information obtained by endosonography in patients with obstructive jaundice due to malignancy is superior to conventional sonography and ERCP.

Adult↗
PubMed1991

Endoscopic ultrasonography of the upper gastrointestinal tract.

EUS unites two established imaging techniques and extends the range of observation into and beyond the wall of the GI tract. The close proximity of the sonographic probe to the region of interest combined with high ultrasonic frequencies of between 7.5 and 12 MHz yields images of high resolution. EUS is used in the staging of benign and malignant neoplastic disorders of the oesophagus, stomach, pancreas and extrahepatic bile ducts. It helps to establish operability, to plan surgical approach, to follow response to therapy and to search for recurrence. The predictive value in defining the T and N stages of oesophageal carcinoma lies between 80 and 90% and 65 and 85%, respectively. It is clearly superior to CT in tumour stages T1 and T2. In gastric cancer, resectability based on the TNM staging system can be correctly assessed by EUS in 85% of cases and EUS detection and staging of early gastric cancer reaches an accuracy of 90%. The EUS accuracy rate for resectability of pancreatic carcinoma is 83% and tumour infiltration into the portal and splenic vein can be correctly determined by EUS in 94% and 67%, respectively. A reliable EUS differentiation between chronic pancreatitis and pancreatic carcinoma based on the echo pattern and outer margins is not possible. The development of EUS-guided needle biopsy should improve the specificity of EUS in this regard. Experience to data suggests as well that EUS will assume an important place in the staging of bile duct tumours. EUS has expanded our endoscopic and sonographic capabilities and it is to be hoped that further technical improvement, e.g. the construction of forward-viewing endoscopes combined with radial scanning devices, will contribute to a widespread use of this technique by gastroenterologists.

Contraindications↗
PubMed1991

[Endoscopic ultrasound in small pancreatic tumors].

32 of 89 pancreatic tumors examined by endoscopic ultrasonography (EUS) from January 1986 to February 1990 had a diameter of 3 cm or less. The final diagnosis of a malignant (n = 28) or benign (n = 4) pancreatic neoplasma was achieved by operation, puncture or autopsy. The accuracy of EUS (100%) was higher than for ultrasound (61%), computed tomography (64%) or endoscopic-retrograde cholangiopancreatography (84%). The echopattern of the small pancreatic carcinomas showed, compared to larger neoplasms, less often regressive changes (21 vs. 77%) and a well demarcated or smooth tumor margin (25 vs. 2%). However, it is not possible to differentiate reliably a small malignant from a benign pancreatic tumor by the echofeatures alone. Since most pancreatic tumors are large at the time of clinical presentation, they can be visualized by conventional imaging methods in most cases. EUS adds clinically important information to the diagnosis of pancreatic carcinoma especially in small tumors.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1990

Effect of thyrotropin-releasing hormone on immune functions of peripheral blood mononuclear cells.

The tripeptide thyrotropin-releasing hormone (TRH) works as a hypothalamic hormone, but is found also outside the brain in intrinsic nerve fibers of the gastrointestinal tract. There is evidence that TRH modulates the activity of immunocompetent cells, although there are only very few data on TRH-mediated immune effector functions. Since we could recently show that TRH inhibits monocyte activities we were also interested in other possible TRH modulated immune functions. Peripheral blood mononuclear cells (PBMC) from ten healthy subjects were cultured for 7 days and pulsed with 0.125 and 0.250 microgram/ml Pokeweed mitogen (PWM). 10(-12) to 10(-6) M TRH was added simultaneously with PWM. Lymphocyte proliferation [(3H]thymidine incorporation), interferon-gamma (IFN-gamma) activity (RIA) and immunoglobulin activities (IgG, IgM, IgA; ELISA) were determined in the supernatants. We could demonstrate a TRH-dependent decrease in PWM-pulsed IgG activity with significant (alpha = 0.05) values at 10(-8) and 10(-10) M (-29 +/- 6%/-16 +/- 3% for PWM 0.125 microgram/ml and -17 +/- 9%/-11 +/- 9% for PWM 0.250 microgram/ml). This inhibitory effect could be abolished by an anti-TRH antiserum. There was no TRH effect on IgM and IgA activities, IFN-gamma activity and lymphocyte proliferation compared with the PWM stimulated values alone. The described TRH effect on the polyclonal IgG response by PBMC gives further evidence for a functional link between the immune system and the endocrine system, although its underlying mechanism is not yet clear.

Enzyme-Linked Immunosorbent Assay↗
PubMed1990

Effect of substance P on immunoglobulin and interferon-gamma secretion by cultured human duodenal mucosa.

Recently, we have demonstrated a substance P (SP)-dependent modulation of in vitro IgM and interferon-gamma (IFN-gamma) secretion by human peripheral blood mononuclear cells, as well as lymphokine activities in supernatants of cultured duodenal mucosa. Therefore we investigated other local immunoregulatory effects of SP. Duodenal biopsies of 7 healthy subjects were cultured with Pokeweed mitogen (PWM, 1 microgram/ml) for 4 days at 37 degrees C in 1 ml medium each. SP was added in concentrations ranging from 10(-12)M to 10(-6)M on day 1. Fresh media with fresh PWM were added every day. IgG, IgM, IgA (ELISA) and IFN-gamma (RIA) were determined in the culture supernatants. Values were referred to 5 mg biopsy weight and expressed as % change in basal PWM pulsed secretion, or as units/ml. 10(-6) M and 10(-12) M SP increased secretion of all immunoglobulin isotypes. Compared to controls, 10(-6) M and 10(-12) M SP led to an increase in IgM secretion of up to 73 +/- 23% and 41 +/- 32% and to an increase in IgA secretion up to 96 +/- 35% and 25 +/- 33%, respectively (alpha = 0.02 for both isotypes at 10(-6) M). 10(-12) M to 10(-6) M SP led to a significant dose-dependent increase in IFN-gamma secretion from 7.08 +/- 1.65 up to 21.8 +/- 12.6 units/ml/5 mg. The maximum effect could be seen on culture days 3 and 4. We were able to demonstrate for the first time that SP stimulates PWM pulsed immunoglobulin and IFN-gamma secretion by human duodenal immunocompetent cells. These results support the hypothesis of local neuropeptidergic-immune interactions.

Adult↗
PubMed1990

Stimulation of the immune response in outpatients with hepatocellular carcinomas by low doses of cyclophosphamide (LDCY), echinacea purpurea extracts (Echinacin) and thymostimulin.

Outpatients with inoperable far advanced hepato-cellular carcinomas (n = 5) were treated with LDCY--300 mg/m2 i.v. every 28 days-, echinacin--60 mg/m2 i.m.--and thymostimulin--30 mg/m2 i.m., day 3-10 after LDCY, then twice a week. Therapy was well tolerated by all patients. Their Karnofsky' index increased for 10% in the mean. A stable disease for more than 8 weeks was documented by abdominal ultrasonography in one patient. Serum levels of Alpha-Fetoprotein (AFP), Carcinoembryonic Antigen (CEA) and Tissue Polypeptide Antigen (TPA) did not increase in 2 patients. Median survival time was 2.5 months. One patient is still alive after 8 months. Absolute numbers of CD8+ cells significantly (p less than 0.02) decreased for 7% 1 day after LDCY, whereas CD4+ cells increased (p less than 0.02) from day 1-7. Numbers of natural killer (NK-) cells increased for 17% (p less than 0.05), their activity for 90% (p less than 0.05). Activities of peripheral polymorphs (p less than 0.05) increased for 27% and of Lymphokine Activated Killer (LAK-) cells for 180% (p less than 0.05).

Adjuvants, Immunologic↗
PubMed1989

Interleukin 4 inhibits the interleukin 2-induced production of its functional antagonist, interferon gamma.

Interferon gamma (IFN gamma) inhibits many effects of interleukin (IL)-4. Its production largely parallels cell proliferation but is regulated independently. As IL-4 inhibits several IL-2-induced effects including proliferation of human peripheral blood mononuclear cells, we investigated its influence on the IL-2-induced IFN gamma production. We found that both absolute IFN gamma production and IFN gamma production per proliferation unit (1000 cpm) in response to IL-2 were inhibited by IL-4. IL-2-induced interferon production was inhibited by IL-4 in both sheep red blood cell rosetting and non-rosetting cells. In bidirectional mixed lymphocyte culture, IL-4 alone enhanced proliferation but suppressed IFN gamma production. As 48% of IFN gamma-producing cells are known to show T cell phenotype, the nearly total inhibition of IFN gamma production is evidence for suppression of T cell response to IL-2. Additionally, we found that the inhibition of IL-2-induced proliferation by IL-4 was significantly more pronounced at low cell densities. Basal proliferation was only inhibited in serum-containing media. These data stress the importance of other lymphokines or accessory cells in the regulation of early lymphocyte activation.

Cells, Cultured↗
PubMed1989

[AIDS manifestations in the gastrointestinal tract].

More than 50% of HIV-infected patients develop gastrointestinal symptoms. The HIV-induced damage of the mucosa-associated immune system (reduction of CD4-positive cells in the lamina propria) leads to an increased risk of opportunistic infections (Candida, Herpes simplex virus, Cytomegalovirus, Cryptosporidia, Isospora belli, Strongyloides stercoralis, Mycobacteria) and the development of malignant tumors (Kaposi's sarcoma, malignant lymphoma). 70% of patients with gastrointestinal Kaposi's sarcoma succumb to opportunistic infections within two years. Furthermore, HIV infection promotes the persistence of hepatitis B virus. Although the risk for health care professionals to acquire HIV infection in hospital is minimal, cases of hospital acquired infection are well documented. Therefore when performing endoscopic examinations on HIV-infected patients protective measures such as the wearing of a cap, eye and mouth protection, gloves and a gown must not be neglected. Endoscopes must be disinfected in accordance to standardized procedures.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Endoscopic sonography of the upper digestive tract].

Endoscopic sonography (EUS) enables systematic and detailed imaging of the wall of the upper gastrointestinal tract and its immediate neighbourhood. Update equipment supplies a circular image and is fitted with an instrumentation channel for executing transmural fine needle biopsies. Preoperative staging of oesophageal and gastric carcinomas is enhanced by EUS. This method should be used with every patient suffering from dysphagia. EUS is the most sensitive method in assessing the extension of gastric lymphomas and in the delineation of small (less than 2 cm) pancreatic tumours. In on-target problems EUS should be used as a method that is complementary to the conventional morphological methods.

Diagnosis, Differential↗
PubMed1989

Endoscopic transpapillary biopsy (ETPB) of human extrahepatic bile ducts--light and electron microscopic findings, clinical significance.

Endoscopic transpapillary biopsy (ETPB) has been performed in 106 patients to investigate the fine structure of human bile ducts, and to assess its clinical significance. Three hundred and twenty-six biopsy specimens obtained from the hepatic and common bile duct and from the ampullary/papillary region were examined by light, transmission and scanning electron microscopy. No complications due to biopsy occurred. The epithelium lining at the bile duct contains 5 different types of cells: the main epithelial cell, endocrine/paracrine cells, tuft cells, immunocompetent cells and goblet cells. Twenty-one ampullary carcinomas, and 26 benign neoplastic ampullary lesions were diagnosed. In 8 of the former, only second-look, follow-up biopsies established the presence of a carcinoma. While the clinical significance of "blind" hepatic duct biopsy is not readily apparent, ETPB is the diagnostic method of choice for ampullary neoplasms, and extensive biopsies from even tiny ampullary lesions are mandatory.

Bile Duct Diseases↗
PubMed1989

Effect of thyrotropin-releasing hormone (TRH) on the chemiluminescence (CL) activity of human mononuclear cells.

The effect of the tripeptide TRH on the chemiluminescence activity of human monocytes was tested. TRH significantly (p less than 0.002) inhibited monocytes activity at pharmacological concentrations of 2 x 10(-4) M/L. The effect was not mediated via Ia or C3a-receptors as was proven by the preincubation of monocytes with the monoclonal antibodies OKIa1 and anti-C3a. Heat inactivation abolished the effect of TRH. This study has demonstrated for the first time, that pharmacological doses of TRH which had already been tentatively employed as a therapeutic agent in men can modulate immunocompetent cells.

Hot Temperature↗
PubMed1988

[Vasoactive intestinal polypeptide influences human immunoglobulin secretion].

Blood lymphocytes from eight subjects were cultured for seven days and stimulated with Pokeweed mitogen. At the same time, vasoactive intestinal polypeptide (VIP) was added in rising concentrations (10(-12) M to 10(-6) M). Immunoglobulin concentrations were measured by ELISA in the remaining cultures. Mitogen-stimulated peripheral mononuclear cells were stimulated dose-dependent by VIP to a further significant rise of IgM secretion in six of the eight subjects. VIP had no influence in this respect on mononuclear cells that had not been prestimulated. This was, therefore, the first demonstration that VIP, in concentrations that occur in intestinal mucosa in certain circumstances, influences human immunoglobulin synthesis in vitro. These findings may provide a building stone towards a better understanding of local immunoregulatory events in the intestinal mucosa.

Cells, Cultured↗
PubMed1988

Preoperative staging of a distal common bile duct tumor by endoscopic ultrasound.

A 27-yr-old man with a long-standing history of primary sclerosing cholangitis presented with recurrent episodes of fever and progressive weight loss over 6 mo. The diagnosis of a distal cholangiocarcinoma was made by endoscopic retrograde cholangiography and transpapillary biopsy. The extent of the tumor could be reliably assessed by endoscopic ultrasound, whereas computed tomography scan, angiography, and transabdominal ultrasound failed to visualize the tumor. The intraoperative findings and histologic work-up of the resected specimen confirmed a T3N0M0 adenocarcinoma of the distal common bile duct.

Adenocarcinoma↗