Weld procedure produces quality welds for thick sections of Hastelloy-X

Welding program produces premium quality, multipass welds in heavy tube sections of Hastelloy-X. It develops semiautomatic tungsten/inert gas procedures, weld wire procurement specifications material weld properties, welder-operator training, and nondestructive testing inspection techniques and procedures

Extramural Venous Invasion as Prognostic Factor of Recurrence in Stage 1 and 2 Colon Cancer

Aim. Extramural venous invasion (EMVI) is a prognostic indicator in patients with colorectal cancer. However, its additional value in patients with stage 1 and 2 colorectal cancer is uncertain. In the present study, the incidence of EMVI and the hazard ratio for recurrence in patients with stage 1 and 2 colon cancer were studied. Methods. 184 patients treated for stage 1 and 2 colon cancer were included with a follow-up of at least 5 years. Chart review was performed and EMVI was assessed by two separate pathologists. EMVI was scored with additional caldesmon staining on the resection specimen. Primary outcomes were recurrence-free survival (RFS) measured through the Cox regression analysis and prevalence of EMVI. Results. There were 10 cases of EMVI and 3 cases of intramural venous invasion (IMVI) all occurring in patients with stage 2 disease corresponding to a prevalence of 9%. Thirty-one percent of the patients with venous invasion experienced recurrence versus 14% in patients without, corresponding with a hazard ratio of 2.39 (p=0.11). Conclusion. The present study demonstrates a trend towards an increased risk of recurrence in patients with stage 2 colon cancer with venous invasion. This warrants consideration of adjuvant chemotherapy despite the lack of lymph node metastases

Altered MRP is associated with multidrug resistance and reduced drug accumulation in human SW-1573 cells.

We have analysed the contribution of several parameters, e.g. drug accumulation, MDR1 P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP) and topoisomerase (topo) II, to drug resistance in a large set of drug-resistant variants of the human non-small-cell lung cancer cell line SW-1573 derived by selection with low concentrations of doxorubicin or vincristine. Selection with either drug nearly always resulted in MDR clones. The resistance of these clones could be explained by reduced drug accumulation and was associated with a decrease rather than an increase in the low MDR1 mRNA level. To test whether a decrease in MDR1 mRNA indirectly affected resistance in these cells, we introduced a MDR1-specific hammerhead ribozyme into wild-type SW-1573 cells. Although this led to a substantial reduction in MDR1 mRNA, it did not result in resistance. In all resistant clones we found an altered form of the multidrug resistance-associated protein (MRP), migrating slightly slower during SDS-polyacrylamide gel electrophoresis than MRP in parental cells. This altered MRP was also present in non-P-gp MDR somatic cell hybrids of the SW-1573 cells, demonstrating a clear linkage with the MDR phenotype. Treatment of crude cellular membrane fractions with N-glycanase, endoglycosidase H or neuraminidase showed that the altered migration of MRP on SDS-PAGE is due to a post-translational modification. There was no detectable difference in sialic acid content. In most but not all doxorubicin-selected clones, this MDR phenotype was accompanied by a reduction in topo II alpha mRNA level. No reduction was found in the clones selected with vincristine. We conclude from these results that selection of the SW-1573 cell line for low levels of doxorubicin or vincristine resistance, predominantly results in MDR with reduced drug accumulation associated with the presence of an altered MRP protein. This mechanism can be accompanied by other resistance mechanisms, such as reduced topo II alpha mRNA in case of doxorubicin selection

Selection and characterisation of a phage-displayed human antibody (Fab) reactive to the lung resistance-related major vault protein

The major vault protein is the main component on multimeric vault particles, that are likely to play an essential role in normal cell physiology and to be associated with multidrug resistance of tumour cells. In order to unravel the function of vaults and their putative contribution to multidrug resistance, specific antibodies are invaluable tools. Until now, only conventional major vault protein-reactive murine monoclonal antibodies have been generated, that are most suitable for immunohistochemical analyses. The phage display method allows for selection of human antibody fragments with potential use in clinical applications. Furthermore, cDNA sequences encoding selected antibody fragments are readily identified, facilitating various molecular targeting approaches. In order to obtain such human Fab fragments recognising major vault protein we used a large non-immunized human Fab fragment phage library. Phages displaying major vault protein-reactive Fabs were obtained through several rounds of selection on major vault protein-coated immunotubes and subsequent amplification in TG1 E coli bacteria. Eventually, one major vault protein-reactive clone was selected and further examined. The anti-major vault protein Fab was found suitable for immunohistochemical and Western blot analysis of tumour cell lines and human tissues. BIAcore analysis showed that the binding affinity of the major vault protein-reactive clone almost equalled that of the murine anti-major vault protein Mabs. The cDNA sequence of this human Fab may be exploited to generate an intrabody for major vault protein-knock out studies. Thus, this human Fab fragment should provide a valuable tool in elucidating the contribution(s) of major vault protein/vaults to normal physiology and cellular drug resistance mechanisms

Functional Evidence of Multidrug Resistance Transporters (MDR) in Rodent Olfactory Epithelium

Background: P-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP1) are membrane transporter proteins which function as efflux pumps at cell membranes and are considered to exert a protective function against the entry of xenobiotics. While evidence for Pgp and MRP transporter activity is reported for olfactory tissue, their possible interaction and participation in the olfactory response has not been investigated. Principal Findings: Functional activity of putative MDR transporters was assessed by means of the fluorometric calcein acetoxymethyl ester (calcein-AM) accumulation assay on acute rat and mouse olfactory tissue slices. Calcein-AM uptake was measured as fluorescence intensity changes in the presence of Pgp or MRP specific inhibitors. Epifluorescence microscopy measured time course analysis in the olfactory epithelium revealed significant inhibitor-dependent calcein uptake in the presence of each of the selected inhibitors. Furthermore, intracellular calcein accumulation in olfactory receptor neurons was also significantly increased in the presence of either one of the Pgp or MRP inhibitors. The presence of Pgp or MRP1 encoding genes in the olfactory mucosa of rat and mouse was confirmed by RT-PCR with appropriate pairs of speciesspecific primers. Both transporters were expressed in both newborn and adult olfactory mucosa of both species. To assess a possible involvement of MDR transporters in the olfactory response, we examined the electrophysiological response to odorants in the presence of the selected MDR inhibitors by recording electroolfactograms (EOG). In both animal species

Cytokeratin phenotyping does not help in distinguishing oesophageal adenocarcinoma from cancer of the gastric cardia

Background: It is sometimes difficult to distinguish between cardia cancer and oesophageal cancer. Aims: To evaluate whether cytokeratin (CK) expression of the tumour can be of value in differentiating between the two tumour types. Methods: Consecutive patients with a malignant tumour in the oesophagus or stomach were recruited. Biopsy specimens were taken for routine haematoxylin and eosin staining. One tissue block with representative tissue was selected for immunohistochemical staining (CK7 and CK20). Results: Endoscopically located adenocarcinoma of the oesophagus was present in 84 patients (64 men, 20 women; mean age, 68 years; range, 44–91). Cancer located primarily in the gastric cardia was present in 63 patients (42 men, 21 women; mean age, 68 years; range, 42–88). The histological diagnosis was metastasis from a primary tumour outside the oesophagus or stomach in 19 patients. The patients were divided into three groups for the immunohistochemical analysis. Patients in group A had definite oesophageal cancer, group B patients had a definite carcinoma located in the gastric cardia, and group C patients had an obstructing tumour distal in the oesophagus at the level of the diaphragm, which could not be passed with the endoscope. Paraffin wax embedded material was available from 122 patients for immunostaining and CK analysis. There was no significant difference in expression or distribution of CK7 or CK20 in the three groups of patients. Conclusion: CK phenotyping cannot distinguish between cancer arising from a Barrett’s oesophagus and carcinoma originating in the gastric cardia