Importance of extensive staging in patients with mucosa-associated lymphoid tissue (MALT)-type lymphoma

Lymphoma of the mucosa-associated lymphoid tissue (MALT) type usually arises in MALT acquired through chronic antigenic stimulation triggered by persistent infection and/or autoimmune processes. Due to specific ligand–receptor interactions between lymphoid cells and high-endothelial venules of MALT, both normal and neoplastic lymphoid cells display a pronounced homing tendency to MALT throughout the body. In the case of neoplastic disease these homing properties may be responsible for lymphoma dissemination among various MALT-sites. According to this concept, we have standardized staging procedures in all patients diagnosed with MALT-type lymphoma. All patients with MALT-type lymphoma underwent standardized staging procedures before treatment. Staging included ophthalmologic examination, otolaryngologic investigation, gastroscopy with multiple biopsies, endosonography of the upper gastrointestinal tract, enteroclysis, colonoscopy, computed tomography of thorax and abdomen and bone marrow biopsy. Biopsy was performed in all lesions suggestive for lymphomatous involvement, and evaluation of all biopsy specimens was performed by a reference pathologist. 35 consecutive patients with histologically verified MALT-type lymphoma were admitted to our department. Twenty-four patients (68%) had primary involvement of the stomach, five (15%) had lymphoma of the ocular adnexa, three (8.5%) had lymphoma of the parotid, and three (8,5%) of the lung. Lymph-node involvement corresponding to stage EII disease was found in 13 patients (37%), only one patient with primary gastric lymphoma had local and supradiaphragmatic lymph-node involvement (stage EIII). Bone marrow biopsies were negative in all patients. Overall, eight of 35 patients (23%) had simultaneous biopsy-proven involvement of two MALT-sites: one patient each had lymphoma of parotid and lacrimal gland, conjunctiva and hypopharynx, conjunctiva and skin, lacrimal gland and lung, stomach and colon, and stomach and lung. The remaining two patients had bilateral parotideal lymphoma. Staging work-up was negative for lymph-node involvement in all of these eight patients. The importance of extensive staging in MALT-type lymphoma is emphasized by the demonstration of multiorgan involvement in almost a quarter of patients. In addition, our data suggest that extra-gastrointestinal MALT-type lymphoma more frequently occurs simultaneously at different anatomic sites than MALT-type lymphoma involving the GI-tract. © 2000 Cancer Research Campaig

Treatment of advanced pancreatic cancer with the long-acting somatostatin analogue lanreotide: in vitro and in vivo results

Fourteen patients with metastatic pancreatic adenocarcinoma were treated with the long-acting somatostatin (SST) analogue lanreotide. No objective response was obtained, and the median survival was 4 months (range 1.8–7 months). Pancreatic cancer could not be visualized by means of SST-receptor (R) scintigraphy in our patients. In vitro data also demonstrated absence of SSTR2 expression, suggesting pancreatic cancer not to be a potential target for treatment with SST analogues. © 1999 Cancer Research Campaig

Structural and functional properties of ribosomal protein L7 from humans and rodents.

By subtractive screening of a library made from mRNA of lipopolysaccharide (LPS)-stimulated mouse B lymphocytes we isolated cDNA-clones encoding the ribosomal protein L7. Human L7 mRNA was cloned from activated T-lymphocytes. Although no specific function of L7 in the translation apparatus is known as yet, it should be a critical one as indicated by its high degree of structural conservation during evolution and its regulated expression in lymphoid cells. Human and rodent L7 proteins carry sequences similar to the basic-region-leucine-zipper(BZIP)-motif of DNA-binding eucaryotic transcription factors. We show here that the region of L7 carrying the latter motif mediates L7-dimerization and stable binding to DNA and RNA. A preferential binding to RNA-structures is demonstrated

Primary hepatocytes of Tupaia belangeri as a potential model for hepatitis C virus infection

Hepatitis C virus (HCV) is a major cause of chronic hepatitis worldwide, but the study of HCV infection has been hampered by the lack of an in vitro or in vivo small animal model. The tree shrew Tupaia belangeri is susceptible to infection with a variety of human viruses in vivo, including hepatitis viruses. We show that primary Tupaia hepatocytes can be infected with serum- or plasma-derived HCV from infected humans, as measured by de novo synthesis of HCV RNA, analysis of viral quasispecies evolution, and detection of viral proteins. Production of infectious virus could be demonstrated by passage to naive hepatocytes. To assess whether viral entry in Tupaia hepatocytes was dependent on the recently isolated HCV E2 binding protein CD81, we identified and characterized Tupaia CD81. Sequence analysis of cloned Tupaia cDNA revealed a high degree of homology between Tupaia and human CD81 large extracellular loops (LEL). Cellular binding of E2 and HCV infection could not be inhibited by anti-CD81 antibodies or soluble CD81-LEL, suggesting that viral entry can occur through receptors other than CD81. Thus, primary Tupaia hepatocytes provide a potential model for the study of HCV infection of hepatocytes

Metallorganische Gasphasenepitaxie und Untersuchung von Gruppe III-Nitriden fuer blaue Leuchtdioden Abschlussbericht

Within this research project, we have investigated the metalorganic vapor phase epitaxy and characteristics of GaInN-GaN hetero structures for LED applications. We focused our studies on the epitaxy on SiC substrates and the investigation of GaInN structures. We found taht for high quality GaN on SiC, an Al containing intermediate layer is necessary. An AlGaN buffer layer containing only 10% Al is well suited and may be useful as conducting buffer in optoelectronic devices. When depositing GaInN, secondary epitaxial parameters like temperature, growth rate or carrier gas composition determine the In incorporation efficiency. We found that even fairly thick GaInN layers may be pseudomorphicly strained. In consequence, large inner piezoelectric fields exist which strongly influence the spectroscopic data and probably device performance. Our studies on p-doping of GaN with Mg resulted in low resistivities of about 2 #OMEGA#cm. Additionally, we studied the selective growth of GaInN-GaN structures. We found that the mask geometry determined thickness inhomogeneity increases also the composition inhomogeneity making this approach less promising for device production. (orig.)SIGLEAvailable from TIB Hannover: F98B1357+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman