| 1. |
- Radecka, Eva, et al.
(författare)
-
An unusual case of tumor thrombus in the inferior vena cava : A case report
- 2003
-
Ingår i: Acta Radiologica. - 0284-1851 .- 1600-0455. ; 44:2, s. 160-161
-
Tidskriftsartikel (refereegranskat)abstract
- Adrenal cortical carcinoma (ACC) is a rare malignancy. Patients present either with a functional tumor or secondary to mass effect. In non-functioning tumors, the tumor size often exceeds 5 cm by the time of diagnosis, and tumor thrombus can occur. We report on a case of a small non-functioning ACC causing a large tumor thrombus in the inferior vena cava.
|
|
| 2. |
|
|
| 3. |
- Bergström, Mats, et al.
(författare)
-
PET imaging of adrenal cortical tumors with the 11beta-hydroxylase tracer 11C-metomidate
- 2000
-
Ingår i: Journal of Nuclear Medicine. - 0161-5505 .- 1535-5667. ; 41:2, s. 275-282
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of the study was to evaluate PET with the tracer 11C-metomidate as a method to identify adrenal cortical lesions.METHODS:PET with 11C-metomidate was performed in 15 patients with unilateral adrenal mass confirmed by CT. All patients subsequently underwent surgery, except 2 who underwent biopsy only. The lesions were histopathologically examined and diagnosed as adrenal cortical adenoma (n = 6; 3 nonfunctioning), adrenocortical carcinoma (n = 2), and nodular hyperplasia (n = 1). The remaining were noncortical lesions, including 1 pheochromocytoma, 1 myelolipoma, 2 adrenal cysts, and 2 metastases.RESULTS:All cortical lesions were easily identified because of exceedingly high uptake of 11C-metomidate, whereas the noncortical lesions showed very low uptake. High uptake was also seen in normal adrenal glands and in the stomach. The uptake was intermediate in the liver and low in other abdominal organs. Images obtained immediately after tracer injection displayed high uptake in the renal cortex and spleen. The tracer uptake in the cortical lesions increased throughout the examination. For quantitative evaluation of tracer binding in individual lesions, a model with the splenic radioactivity concentration assigned to represent nonspecific uptake was applied. Values derived with this method, however, did show the same specificity as the simpler standardized uptake value concept, with similar difference observed for cortical versus noncortical lesions.CONCLUSION:PET with 11C-metomidate has the potential to be an attractive method for the characterization of adrenal masses with the ability to discriminate lesions of adrenal cortical origin from noncortical lesions.
|
|
| 4. |
- Bhattacharyya, T, et al.
(författare)
-
Synthesis of chiral, amphiphilic, and water-soluble chiral macrocycles via urea formation.
- 2003
-
Ingår i: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 59:40, s. 7921-7928
-
Tidskriftsartikel (refereegranskat)abstract
- A simple, efficient, and flexible procedure for the synthesis of chiral, amphiphilic, and water-soluble macrocycles is reported. Acylation of p-xylylenediamine with N-Fmoc-protected glycine, -aspartic acid, -glutamic acid, and -arginine, followed by removal of Fmoc-groups, gave amino acid:p-xylylene conjugate diamines, which were converted to ten macrocycles via stepwise urea formation using p-nitrophenyl chloroformate. -Aspartic acid-containing macrocyles proved to be soluble in aqueous buffers and a macrocycle containing four aspartate residues was found to recognize arginine and arginine esters with moderate affinity.
|
|
| 5. |
- Brandänge, S, et al.
(författare)
-
Highly diastereoselective hydrogenations leading to ß-hydroxy ∂-lactones in hydroxy-protected form. A modified view of ∂-lactone conformations.
- 2003
-
Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 125:39, s. 11942-11955
-
Forskningsöversikt (refereegranskat)abstract
- Enol MEM ethers 4 and 15 and the corresponding enol acetates were hydrogenated over Pd/C with very high (>99%) diastereoselectivity to saturated -lactones. A stereochemical generalization can be formulated thus: trans-5,6-disubstituted 1-oxa-3-cyclohexen-2-ones (e.g. 14 and 15) are hydrogenated over Pd with high selectivity from the side trans to the C(6)-substituent. A mechanistic rationalization of the stereochemical outcome in the Pd-catalyzed hydrogenation of this as well as other types of substituted ,-unsaturated -lactones is presented. An analysis of X-ray crystallographic data for 67 compounds demonstrated a great conformational diversity of the saturated -lactone ring. Besides, ab initio calculations (HF/6-31G*) indicated a very high conformational mobility. Thus, the lowest calculated transition state for the conversion of the half-chair, most stable, conformer of -valerolactone to the boat-type conformer lies only 1.93 kcal/mol above the former. Beside these two conformers, also chair, envelope and skew conformations are accessible; all lie less than 2 kcal/mol above the half-chair. The previous conformational paradigm comprising only boat and half-chair types is incomplete
|
|
| 6. |
|
|
| 7. |
- Dukic, Tania, 1975, et al.
(författare)
-
To use virtual tools for further development of Volvo Car´s production system - A case study of the development of the production system for P28/XC90.
- 2002
-
Ingår i: Chalmers, Produkt- och Produktionsutveckling. Rapport nr. 16. - 1651-0984. ; , s. 112-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- SummaryA work procedure for virtual product and manufacturing engineering has been developed at the Volvo Car Corporation. For the first time this was fully adhered to during the development of the P28/XC90 car model. The working methods comprise both virtual and physical analysis of different aspects of the product and production process, such as packing, assembly ability and ergonomics. A decision was taken in January 2001 to make an evaluation of the virtual working methods, for which a research team from the National Institute for Working Life and Chalmers University of Technology was engaged.The purpose was to evaluate how well the virtual working methods functioned with regard to ergonomics aspects of assembly work - and to what degree they could be applied for early identification of ergonomics problems. About 30 interviews with members of different development teams (module teams) were carried out for the evaluation. Evaluations of the assembly work for a selected number of PIIs1 for P28 were also made, starting with virtual series2 5 (VS5) in February 2001 ending with the pre-series PTO1 (Pre try-out 13) in November 2001. The overall results showed that the virtual participative working methods worked well in general and the members of the module teams (project teams) were very positive to the usage of virtual tools. A large number of ergonomic problems were identified and corrected but the number of ergonomic simulations was lower than expected. The reason for this was said to be a lack of ergonomics competence. Nevertheless the module teams believed that there was a greater potential for identifying and solving several ergonomic problems in early project phases than was the case in this study. An overall important outcome was the recommendations to the company for how to improve virtual working procedures, follow-ups of simulation results and virtual tools for the future.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Eriksson, Barbro, et al.
(författare)
-
The role of PET in localization of neuroendocrine and adrenocortical tumors
- 2002
-
Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923 .- 1749-6632. ; 970, s. 159-169
-
Tidskriftsartikel (refereegranskat)abstract
- Positron emission tomography (PET) supplies a range of labeled compounds to be used for the characterization of tumor biochemistry. Some of these have proved to be of value for clinical diagnosis, treatment follow up, and clinical research. The first routinely used PET tracer in oncology, 18F-labeled deoxyglucose (FDG), was successfully used for diagnosis of cancer, reflecting increased expression of glucose transporter in cancerous tissue. This tracer, however, usually does not show sufficient uptake in well-differentiated tumors such as neuroendocrine tumors. We developed a tracer more specific to neuroendocrine tumors—the serotonin precursor 5-hydroxytryptophan (5-HTP) labeled with 11C—and demonstrated increased uptake and irreversible trapping of this tracer in carcinoid tumors. The uptake was so selective and the resolution was so high that we could detect more liver and lymph node metastases with PET than with CT or octreotide scintigraphy. To further improve the method, especially to reduce the high renal excretion of the tracer producing streaky artifacts in the area of interest, we introduced premedication by the decarboxylase inhibitor carbidopa, leading to a six-fold decreased renal excretion while the tumor uptake increased three-fold, hence improving the visualization of the tumors.11C-labeled l-DOPA was evaluated as an alternative tracer, especially for endocrine pancreatic tumors, which usually do not demonstrate enhanced urinary serotonin metabolites. However, only half of the EPTs, mainly functioning tumors, could be detected with l-DOPA. Instead 5-HTP seems to be a universal tracer for EPT and foregut carcinoids. With new, more sensitive PET cameras, larger field of view and procedures for whole-body coverage, the PET examination with 5-HTP is now routinely performed as reduced whole-body PET examinations with coverage of the thorax and abdomen. With this method we have been able to visualize small neuroendocrine lesions in the pancreas and thorax (e.g., ACTH-producing bronchial carcinoids) not detectable by any other method, including octreotide scintigraphy, MRI, and CT. Another tracer, the 11β-hydroxylase inhibitor, metomidate labeled with 11C, was developed to simplify diagnosis and follow-up of patients with incidentalomas. A large series of patients with incidentally found adrenal masses have been investigated and so far all lesions of adrenocortical origin have been easily identified because of exceedingly high uptake of 11C-metomidate, whereas noncortical lesions showed very low uptake. In addition, adrenocortical cancer shows high uptake, suggesting that this PET tracer can be used for staging purposes.
|
|
