Biomedical subjects

A Ulrich

Publications and source records attributed to A Ulrich.

At least 37 records · Page 2Linked to original sources

PubMed2001

Description of Microbacterium foliorum sp. nov. and Microbacterium phyllosphaerae sp. nov., isolated from the phyllosphere of grasses and the surface litter after mulching the sward, and reclassification of Aureobacterium resistens (Funke et al. 1998) as Microbacterium resistens comb. nov..

The taxonomic position of a group of coryneform bacteria isolated from the phyllosphere of grasses and the surface litter after sward mulching was investigated. On the basis of restriction analyses of 16S rDNA, the isolates were divided into two genotypes. According to the 16S rDNA sequence analysis, representatives of both genotypes were related at a level of 99.2% similarity and clustered within the genus Microbacterium. Chemotaxonomic features (major menaquinones MK-12, MK-11 and MK-10; predominating iso- and anteiso-branched cellular fatty acids; G+C content 64-67 mol%; peptidoglycan-type B2beta with glycolyl residues) corresponded to this genus as well. DNA-DNA hybridization studies showed a reassociation value of less than 70% between representative strains of both subgroups, suggesting that two different species are represented. Although the extensive morphological and physiological analyses did not reveal any differentiating feature for the genotypes, differences in the presence of the cell-wall sugar mannose enabled the subgroups to be distinguished from one another. DNA-DNA hybridization with type strains of closely related Microbacterium spp. indicated that the isolates represent two individual species, which can also be differentiated from previously described species of Microbacterium on the basis of biochemical features. As a result of phenotypic and phylogenetic analyses, the species Microbacterium foliorum sp. nov., type strain P 333/02T (= DSM 12966T = LMG 19580T), and Microbacterium phyllosphaerae sp. nov., type strain P 369/06T (= DSM 13468T = LMG 19581T), are proposed. Furthermore, the reclassification of Aureobacterium resistens (Funke et al. 1998) as Microbacterium resistens (Funke et al. 1998) comb. nov. is proposed.

Actinomycetales↗

PubMed2001

Inhibition of acetyl coenzyme A carboxylase activity restores expression of the INO1 gene in a snf1 mutant strain of Saccharomyces cerevisiae.

Mutations in the Saccharomyces cerevisiae SNF1 gene affect a number of cellular processes, including the expression of genes involved in carbon source utilization and phospholipid biosynthesis. To identify targets of the Snf1 kinase that modulate expression of INO1, a gene required for an early, rate-limiting step in phospholipid biosynthesis, we performed a genetic selection for suppressors of the inositol auxotrophy of snf1Delta strains. We identified mutations in ACC1 and FAS1, two genes important for fatty acid biosynthesis in yeast; ACC1 encodes acetyl coenzyme A carboxylase (Acc1), and FAS1 encodes the beta subunit of fatty acid synthase. Acc1 was shown previously to be phosphorylated and inactivated by Snf1. Here we show that snf1Delta strains with increased Acc1 activity exhibit decreased INO1 transcription. Strains carrying the ACC1 suppressor mutation have reduced Acc1 activity in vitro and in vivo, as revealed by enzymatic assays and increased sensitivity to the Acc1-specific inhibitor soraphen A. Moreover, a reduction in Acc1 activity, caused by addition of soraphen A, provision of exogenous fatty acid, or conditional expression of ACC1, suppresses the inositol auxotrophy of snf1Delta strains. Together, these findings indicate that the inositol auxotrophy of snf1Delta strains arises in part from elevated Acc1 activity and that a reduction in this activity restores INO1 expression in these strains. These results reveal a Snf1-dependent connection between fatty acid production and phospholipid biosynthesis, identify Acc1 as a Snf1 target important for INO1 transcription, and suggest models in which metabolites that are generated or utilized during fatty acid biosynthesis can significantly influence gene expression in yeast.

AMP-Activated Protein Kinases↗

PubMed2001

Experimental animal models in pancreatic carcinogenesis: lessons for human pancreatic cancer.

The silent course of pancreatic cancer and its explosive fatal outcome have hindered studies of tumor histogenesis and the identification of early biochemical and genetic alterations that could help to diagnose the disease at a curable stage and develop therapeutic strategies. Experimental animal models provide important tools to assess risk factors, as well as preventive and therapeutic possibilities. Although several pancreatic cancer models presently exist, only models that closely resemble human tumors in morphological, clinical, and biological aspects present useful media for preclinical studies. Because an estimated 70% of human tumors are induced by carcinogens and because a significant association has been found between cigarette smoking and pancreatic cancer, chemically induced models are of particular value. Moreover, in such models the etiology, modifying factors, effects of diets, and naturally occurring products can be studied and early diagnostic, preventive, and therapeutic possibilities sought out. Many of the existing models are described in this review, and the advantages and shortcomings of each model and their clinical implications are discussed.

Animals↗

PubMed2001

Expression of nerve growth factors in pancreatic neural tissue and pancreatic cancer.

One of the characteristics of pancreatic cancer is its tendency to invade neural tissue. We hypothesized that the affinity of cancer cells for nerve tissue is related to the presence of growth factors in neural tissue and their receptors in cancer cells. Sections of pancreatic cancer and normal pancreatic tissue were examined by immunohistochemistry for the expression of the neurotrophins NGF, BDNF, NT-3, NT-4, and their receptors TrkA, TrkB, and TrkC, as well as the low-affinity receptor, p75NTR. TrkA expression was found in duct, islet, and cancer cells; TrkB was found in the alpha-cells of the islet only. The anti-pan-Trk antibody (TrkB3), which is presumed to recognize all three receptors, immunoreacted with duct and acinar cells in normal tissue and with cancer cells. The staining with TrkC was similar to that of TrkA. The low-affinity receptor p75NTR was expressed in the neural tissue and in scattered duct cells of the normal tissue only. Duct and acinar cells, as well as neural tissue and cancer cells, showed weak to strong immunoreactivity with NGF. NT-3 expression was noted in capillary endothelia and erythrocytes. NT-4 showed specific staining for ductule cells. The expression and distribution of neurotrophins and their receptors suggest their role in the potential of pancreatic cancer cells for neural invasion.

Humans↗

PubMed2001

Combination of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and actinomycin D induces apoptosis even in TRAIL-resistant human pancreatic cancer cells.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a novel member of the tumor necrosis factor superfamily of cytokines that induces cell death by apoptosis. TRAIL has been shown to be effective in almost two-thirds of solid tumors tested thus far, but its effect on pancreatic cancer cells is unknown. We tested the effect of TRAIL on seven human pancreatic cancer cell lines (HPAF, Panc1, Miapaca2, Bxpc3, Panc89, SW979, and Aspc1) in vitro. Of these cell lines, all but Aspc1 showed a significant dose-dependent increase in apoptosis. The apoptotic rate, as detected by a terminal deoxynucleotidyl transferase-mediated nick end labeling assay, was highest in Bxpc3 (71.5%), followed by HPAF (38.0%), Miapaca2 (24.9%), Panc1 (16.1%), Panc89 (15.8%), SW979 (13.9%), and Aspc1 (5.2%). Multiple treatments were more effective than a single treatment and caused a sustained and profound cell death in all but Aspc1 cells. There was no correlation between the effect of TRAIL and the differentiation grade of the cell lines, p53 mutation, or bcl-2 or bax expression. The resistance of Aspc1 cells to TRAIL was not related to the lack of TRAIL receptors. The combination of actinomycin D and TRAIL induced an almost complete lysis of Aspc1 cells, whereas actinomycin D alone had no effect on cell survival but inhibited the expression of the Flice inhibitory protein, which is assumed to play a role in the apoptotic pathway of TRAIL. Thus, the combination of actinomycin D and TRAIL appears to be a promising approach for the therapy of pancreatic cancers resistant to TRAIL.

Antibiotics, Antineoplastic↗

PubMed2000

Membrane binding of MARCKS-related protein studied by tryptophan fluorescence spectroscopy.

MARCKS-related protein (MRP) is a peripheral membrane protein whose binding to membranes is mediated by the N-terminal myristoyl moiety and a central, highly basic effector domain. MRP mediates cross-talk between protein kinase C and calmodulin and is thought to link the actin cytoskeleton to the plasma membrane. Since MRP contains no tryptophan residues, we mutated a phenylalanine in the effector domain to tryptophan (MRP F93W) and used fluorescence spectroscopy to monitor binding of the protein to phospholipid vesicles. We report in detail the evaluation procedure necessary to extract quantitative information from the raw data. The spectra of MRP F93W obtained in the presence of increasing amounts of lipid crossed at an isosbestic point, indicating a simple transition between two states: free and membrane-bound protein. The change in fluorescence toward values typical of a more hydrophobic environment was used to quantify membrane binding. The partition coefficient agreed well with values obtained previously by other methods. To study the interaction of the N-terminus of MRP with membranes, a tryptophan residue was also introduced at position 4 (MRP S4W). Our data suggest that only the myristoylated N-terminus interacted with liposomes. These results demonstrate the versatility of site-directed incorporation of tryptophan residues to study protein-membrane interactions.

Amino Acid Sequence↗

PubMed2000

Mapping the interface between calmodulin and MARCKS-related protein by fluorescence spectroscopy.

MARCKS-related protein (MRP) is a myristoylated protein kinase C substrate that binds calmodulin (CaM) with nanomolar affinity. To obtain structural information on this protein, we have engineered 10 tryptophan residues between positions 89 and 104 in the effector domain, a 24-residue-long amphipathic segment that mediates binding of MRP to CaM. We show that the effector domain is in a polar environment in free MRP, suggesting exposure to water, in agreement with a rod-shaped structure of the protein. The effector domain participates in the binding of MRP to CaM, as judged by the dramatic changes observed in the fluorescent properties of the mutants on complex formation. Intermolecular quenching of the fluorescence emission of the tryptophan residues in MRP by selenomethionine residues engineered in CaM reveals that the N-terminal side of the effector domain contacts the C-terminal domain of CaM, whereas the C-terminal side of the effector domain contacts the N-terminal domain of CaM. Finally, a comparison of the fluorescent properties of the myristoylated and unmyristoylated forms of a construct in which a tryptophan residue was introduced at position 4 close to the myristoylated N terminus of MRP suggests that the lipid moiety is also involved in the interaction of MRP with CaM.

Amino Acid Sequence↗

PubMed2000

In vitro induction of giant cell tumors from cultured hamster islets treated with N-Nitrosobis(2-Oxopropyl)amine.

Giant cell carcinoma of the pancreas is a rare tumor. Its histogenesis is still controversial. In a Syrian hamster pancreatic cancer model, tumors similar to human giant cell carcinomas have been induced at an extremely low rate of incidence and after the use of high doses of pancreatic carcinogens. Thus far no tumors of giant cell type have been induced by the in vitro treatment of hamster pancreatic ductal cells with the potent pancreatic carcinogen N-nitrosobis(2-oxopropyl)amine (BOP). In the present study we report the induction of giant cell carcinoma from hamster islets treated with BOP in vitro. The results suggest that in hamsters some component of islet cells, probably stem cells, are the origin of giant cell carcinoma.

Animals↗

PubMed2000

Maintenance of human islets in long-term culture.

The long-term maintenance of human islets in culture has remained a challenge. Despite advancements in culture techniques, human islets proved to have a short life span in vitro. For the first time, we have succeeded in maintaining human islets in a defined culture medium for more than 12 months. Freshly isolated islets from a 38-year-old donor were cultured in M3:5 medium and placed on a rocker for 14 days to remove contaminated exocrine and mesenchymal cells which attached to the bottom. The floating islets were purified by daily hand-picking and transfer into fresh medium. After 14 days, purified islets were allowed to attach to the bottom of the flasks and to expand. At various time points, islets were examined immunohistochemically and electron microscopically, and the secretion of islet hormones and their mRNA were determined by radioimmunoassay and reverse transcriptase polymerase chain reaction, respectively. Within seven days of culture, ductular and acinar cells developed within the initially normal islets. With time, exocrine cell types expanded while the number of the endocrine cells and their secretion decreased. At day 60, only a few endocrine cells were identifiable, whereas most of the cells appeared undifferentiated and expressed cytokeratin 7 and 19, neuron specific enolase, tomato lectin, phaseolus leucoagglutinin, laminin, and vimentin. After 60 days, the culture consisted entirely of undifferentiated cells which could be maintained in culture for 270 days before they became senescent. This is the first report on the long-term maintenance of human islet cells in culture and allows an insight into the complex process of endocrine cell differentiation.

Adult↗

PubMed2000

Comparison of the hematopoietic activity of flt-3 ligand and granulocyte-macrophage colony-stimulating factor acting alone or in combination.

The hematopoietic sequelae of intramuscular administration of flt-3 ligand (FL) and granulocyte-macrophage colony-stimulating factor (GM-CSF) alone, or in combination, were compared in BALB/c mice. Changes in hematopoiesis were measured in the marrow, spleen and blood using an in vitro colony-forming unit (CFU) assay and flow cytometrically (expression of CD34 and stem cell antigen (Sca)-1). FL administration was associated with a significant increase in the absolute number of CFU and CD34+ cells in the marrow and CFU, CD34+, Sca-1+, and CD34+ Sca-1+ cells in the spleen and blood. These data demonstrate that FL expands and mobilizes a range of hematopoietic progenitors. By comparison, GM-CSF administration was associated with a significant increase in the number of CFU in the spleen and a significant reduction in marrow CD34+, Sca-1+, and CD34+Sca-1+ cells. These data suggest that GM-CSF-driven expansion of CFU may be at the expense of more primitive cells. The pattern of progenitor cell expansion associated with FL + GM-CSF administration was similar to that of FL alone with the following exceptions. The numbers of spleen and blood CFU were significantly greater and the number of marrow CD34+Sca-1+ cells were significantly less, than with FL alone. These data suggest that co-administration of these cytokines may combine the expansion of the more primitive cell populations (associated with FL) with the expansion of the more mature CFU population (associated with GM-CSF) to yield a greater overall CFU expansion and elevation of CFU in the blood. However, increasing the expansion and mobilization of the relatively mature, rather than the more primitive, hematopoietic progenitors, may be of limited value as a mobilization strategy, if the goal is the expansion and isolation of increased numbers of "high-quality," primitive cells for transplantation.

Animals↗

PubMed2000

Differentiation of islet cells in long-term culture.

Our previous studies in the hamster pancreatic cancer model have shown that exocrine pancreatic cancer arises from ductal/ductular cells, as well as from within the islets, most probably from islet precursor (stem) cells. To identify and characterize these cells, we established a long-term culture from isolated hamster islets and investigated their growth, differentiation, and expression of biomarkers. Islets maintained their original form and structure within the first 14 days in culture. However, beginning at day 7, ductular structures began to form within the islets. At day 21 in culture, acinar cells, intermediary cells, oncocytes, and cells comparable to pancreatic hepatocytes also appeared between ductular and endocrine cells. The number of duct-like cells gradually increased, whereas the number of hormone-producing cells decreased. After 35 days in culture, the exocrine cells disappeared, and undifferentiated cells formed a monolayer. These cells expressed cytokeratins, alpha1-antitrypsin, transforming growth factor-alpha, epidermal growth factor receptor, carbonic anhydrase II, vimentin, laminin, and showed binding to tomato lectin and Phaseolus vulgaris leukoagglutinin. They did not express the regulatory transcriptional factors, insulin-promoting factor 1, NKx6.1, Pax6, and NeuroD. The results thus indicate that islet cells have potential to form exocrine cells. At present, it is not clear whether these cells originate from preexisting stem cells or from transdifferentiated islet cells.

Animals↗

PubMed2000

Clinical characteristics as predictors of recurrent alcohol-related seizures.

OBJECTIVE: To determine whether clinical data available in the emergency department can accurately predict a subset of patients at low risk of developing recurrent seizures following one or more initial alcohol-related seizures in the out-of-hospital arena. METHODS: This was a retrospective secondary analysis of data obtained from the placebo arms of two prospective, randomized trials of drug treatments for the prevention of recurrent alcohol-related seizures. Subjects with and without one or more recurrent alcohol-related seizures during the study period were compared according to the following characteristics: 1) age, 2) gender, 3) daily ethanol consumption, 4) years of ethanol abuse, 5) previous alcohol-related seizure, 6) previous seizure of other etiology, 7) temperature, 8) heart rate, 9) systolic blood pressure, 10) diastolic blood pressure, 11) respiratory rate, and 12) ethanol level. Data were analyzed with t-tests and chi-square where appropriate. RESULTS: One hundred five placebo-treated patients were analyzed and 31 (30%) developed recurrent alcohol-related seizures. None of the listed characteristics were statistically different between the two groups except for the initial ethanol level. Subjects with an ethanol level higher than 100 mg/dL were less likely (0%) to develop recurrent seizures than patients with a level equal to or below 100 mg/dL (36%) (p < 0.01). CONCLUSIONS: An initial ethanol level higher than 100 mg/dL was significantly associated with a low risk for recurrent alcohol-related seizures during the observation period. No other low-risk clinical characteristics could be identified.

Adult↗

PubMed1999

Phylogenetic Diversity and Population Densities of Culturable Cellulolytic Soil Bacteria across an Agricultural Encatchment.

> Abstract A typical, small encatchment (catena Bölkendorf) in the moraine, northeast German agricultural landscape Schorfheide-Chorin was studied with respect to summit, midslope, and foot-slope positions at northern and southern slope exposure, respectively, including a central noncultivated kettle hole position (pot hole). Across the sequence of seven distinct sampling positions, soil organic carbon and total nitrogen contents, soil gravimetric water content, and soil microbial biomass displayed maxima at the kettle hole position. Soil pH revealed a decreasing trend at the northern exposed slope and a minimum at the kettle hole position. Against this background, the population density of total culturable bacteria clearly displayed a minimum at the kettle hole position, whereas the population density of carboxymethylcellulose decomposing bacteria was not clearly differentiated in relation to sampling positions. To study the phylogenetic diversity of culturable cellulolytic bacteria, 311 isolates were obtained from the sampling positions across the entire encatchment and examined by restriction analysis of PCR-amplified 16S rDNA. Using the restriction enzyme ScrFI, isolates were classified into 31 pattern groups. Although the ratio of actinomycetes within total isolates ranged from 0.73 to 0.94, only 16 pattern groups originated from actinomycetes, but 15 from other bacteria. At all sampling positions, a dominant pattern group was identified, containing 38 to 65% of total isolates. Two site-specific pattern groups could be identified, representing significant parts of the total population, which were highly specific for the kettle hole (19% of total isolates) and for foot- and midslope positions (15-18% of total isolates), respectively. In general, the composition of cellulolytic isolates across the encatchment displayed differences with respect to slope positions, but was not significantly affected by soil properties. Based on 16S rDNA sequence analysis, isolates of the dominant as well as the specific pattern groups could be assigned to the genus Streptomyces. Furthermore, sequencing of 16S rDNA of isolates of another three pattern groups revealed a high phylogenetic diversity among these isolates, including cellulomonads and bacilli.http://link.springer-ny.com/link/service/journals/00248/bibs/37n4p238.html

Journal Article↗

PubMed1999

Modulation of Heidelberg Retinal Flowmeter parameter flow at the papilla of healthy subjects: effect of carbogen, oxygen, high intraocular pressure, and beta-blockers.

The Heidelberg Retina Flowmeter (HRF) is intended to assess ocular blood flow by scanning laser doppler flowmetry. In the retina and possibly in the optic nerve head, carbogen increases blood flow, whereas pure oxygen or high intraocular pressure (IOP) decrease it. This study addresses whether at the papilla of healthy volunteers, the HRF parameter flow, is modulated by breathing 5% carbogen (5% carbon dioxide + 95% oxygen) for 7 minutes, breathing 100% oxygen for 7 minutes, increasing IOP to 50 mm Hg with a suction cup, or decreasing IOP with a single topical ocular instillation of the beta-blockers 0.5% betaxolol (betoptic) or 0.5% timolol (timoptic). At the papilla (20 degrees x 5 degrees, 256 X 64 pixels), values of HRF parameter, flow (50 X 50) pixels, increased after carbogen (N = 5, P < 0.05), but decreased after oxygen (N = 5, P < 0.05) or IOP increase (N = 5, P < 0.01). Although IOP values were significantly reduced by betaxolol (N = 9, P < 0.05) and timolol (N = 9, P < 0.01), HRF values were only significantly decreased (N = 9, P < 0.05) after timolol. In conclusion, at the papilla of healthy volunteers, a positive correlation exists between changes in values of the HRF-parameter, flow, and stimuli considered to modulate retinal and ONH blood flow. Furthermore, although of unkown clinical relevance, it appears that in contrast to betaxolol, values of the HRF parameter, flow, at the papilla of healthy volunteers are significantly decreased after a single instillation of timolol.

Administration, Inhalation↗

PubMed1999

A taxonomic study of bacteria isolated from grasses: a proposed new species Pseudomonas graminis sp. nov.

The taxonomic position of a yellow-pigmented group of bacteria, isolated from the phyllosphere of grasses was investigated. Results obtained from restriction analysis of amplified 16S rDNA with seven endonucleases (CfoI, HaeIII, AluI, HinfI, MspI, Sau3A and ScrFI) showed identical restriction patterns for each enzyme of all isolates studied, which suggests that all strains belong to the same species. The grass isolates displayed the characteristics of the genus Pseudomonas. They were Gram-negative, aerobic and rod-shaped with polar flagella. Isolates were catalase-positive and oxidase-negative, and unable to oxidize or ferment glucose with the production of acid. The isolates did not reduce nitrate to nitrite but were able to utilize a wide range of compounds individually as a sole carbon source, with preference being given to the utilization of monosaccharides. The disaccharides tested were not utilized as substrates. The DNA base compositions of the tested strains ranged from 60 to 61 mol% G+C. The major isoprenoid quinone of each was ubiquinone Q-9 and hydroxy fatty acids were represented by 3-hydroxydodecanoic acid and 2-hydroxydodecanoic acid. Comparison of 16S rDNA sequences showed that the bacteria were members of the genus Pseudomonas, with similarity values between 91.5 and 97.7%. DNA-DNA hybridization studies with closely related neighbours revealed a low level of homology (< 27%), indicating that the isolates represent an individual species. On the basis of phenotypic and phylogenetic analyses a new species, Pseudomonas graminis sp. nov. (type strain DSM 11363T), is proposed.

Base Sequence↗

PubMed1999

In vitro pancreatic carcinogenesis.

Studies in our laboratories have indicated that pancreatic cancer originates not only from pancreatic ductal/ductular cells but also from within the Langerhans' islets, probably from reserve (precursor, stem) cells. To identify, enrich and characterize these cells, we established a long-term hamster islet culture and studied their growth, differentiation and response to the pancreatic carcinogen, N-nitrosobis(2-oxopropyl)amine (BOP). One group of cultured islets was treated in vitro with BOP (KL5B group) and the other group of islets served as an untreated control (KL5N group). During the early culture days, in both groups all cultured islets showed a progressive loss of endocrine cells and replacement by ductular, acinar and intermediary cells. However, all these cells disappeared after 35 days in culture and gave room to undifferentiated cells, which we believe represent stem cells. No differences were found between KL5N and KL5B cells with regard to cell growth and differentiation until day 35, when the growth of the KL5B cells accelerated and the cells underwent increasing pleomorphism and atypia. At day 133, KL5B cells but not KL5N cells showed colony formation in soft agar and formed invasive, poorly differentiated adenocarcinomas of the ductal type when transplanted into hamsters. All of these tumors showed mutation of the K-ras gene and extensive chromosomal damage. We concluded that like ductal/ductular cells, certain cell populations within islets are responsive to the carcinogenic effect of BOP. We could not ascertain whether these cells present a preexisting (stem, reserve) cell population within the islets or transdifferentiated islet cells.

Animals↗

PubMed1998

Heterogeneity of plant-associated streptococci as characterized by phenotypic features and restriction analysis of PCR-amplified 16S rDNA.

Thirty-five strains of streptococci isolated from forage grasses were examined by restriction analysis of PCR-amplified 16S rDNA. Using a set of seven endonucleases, five 16S rDNA genotypes were obtained. The isolates could be identified as belonging to the species Enterococcus faecium, Ent. mundtii, Ent. faecalis, Ent. casseliflavus and Lactococcus lactis ssp. lactis, respectively. To assign the isolates to one of these species, digestion with the endonuclease HinfI was sufficient. Data obtained from whole-cell protein analysis were in accordance with the species identification. Additionally, three of the five species found were subdivided into two related subgroups. Both methods are suitable for a rapid and unequivocal identification of plant-associated streptococci. The phenotypic characters showed a high diversity and were in some cases contrary to the expected features usually given in genus and species descriptions. The results demonstrated the close relatedness of the determined species in contrast to their high phenotypic heterogeneity.

Bacterial Typing Techniques↗

PubMed1998

[Diagnosis of liver tumors--what is necessary for therapy planning?].

For the surgical treatment of liver tumors, two initial steps are necessary: functional operability must be proven and oncological and local inoperability must be ruled out. The diagnostic process consists of a series of steps, beginning with non-invasive procedures such as laboratory findings and sonography, continuing with CT, CTAP, laparoscopy in the case of hepatic cirrhosis, up to explorative laparotomy. The potential operability is re-checked after each step. Punction, MRI and scintigraphy are implemented in special cases. The early implementation of MRI is of particular value for the diagnosis of certain benign processes.

Diagnostic Imaging↗