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A Rost

Publications and source records attributed to A Rost.

At least 19 recordsLinked to original sources

Nested fermi surface and electronic instability in Ca3Ru2O7.

High-resolution angular resolved photoemission data reveal well-defined quasiparticle bands of unusually low weight, emerging in line with the metallic phase of Ca(3)Ru(2)O(7) below approximately 30 K . At the bulk structural phase transition temperature of 48 K, we find clear evidence for an electronic instability, gapping large parts of the underlying Fermi surface that appears to be nested. Metallic pockets are found to survive in the small, non-nested sections, constituting a low-temperature Fermi surface with 2 orders of magnitude smaller volume than in all other metallic ruthenates. The Fermi velocities and volumes of these pockets are in agreement with the results of complementary quantum oscillation measurements on the same crystal batches.

Journal Article↗

Bendamustine is effective in relapsed or refractory aggressive non-Hodgkin's lymphoma.

BACKGROUND: Bendamustine, an alkylating agent with a nitrogen mustard group and a purine-like benzimidazol group, has been shown to be effective in several solid tumors and indolent non-Hodgkin's lymphomas, but has not yet been studied for efficacy in aggressive lymphomas. PATIENTS AND METHODS: We conducted a phase II study in patients with relapsed or refractory high-grade non-Hodgkin's lymphomas, using bendamustine at a dose of 120 mg/m(2) on days 1 and 2, every 3 weeks for up to six cycles. Twenty-one patients were enrolled; 18 were evaluable for response and toxicity, 10 of whom were refractory to previous chemotherapy. RESULTS: With three patients achieving a complete response (at 6, >or=8 and >or=22 months) and five a partial response (three at 2 months, one at 3 months and one at 10 months), the total response rate of the evaluable patients was 44% (eight out of 18; 38% of all patients). Two complete and two partial responders were refractory to prior treatment. In 10 patients, treatment had to be stopped after one to three cycles due to progressive disease or hematological toxicity (n = 2). Non-hematological side effects were mild. Eight (13%) WHO grade 3 and no grade 4 events were observed in 60 evaluable treatment cycles. Hematologic toxicity was moderate (grade 3 and 4): anemia in five cycles (8%), leukopenia in seven (12%) and thrombocytopenia in eight (13%). CONCLUSIONS: Bendamustine as a single agent is effective against aggressive lymphoma, even in cases of refractory disease. Further studies are warranted to determine the significance of bendamustine in the treatment of aggressive lymphomas.

Adult↗

Phase II study of a weekly 24-hour infusion with 5-fluorouracil and simultaneous sodium-folinic acid in the first-line treatment of metastatic colorectal cancer.

BACKGROUND: A weekly continuous 24-hour infusion therapy with 5-fluorouracil (5-FU) and calcium - folinic acid (CA-FA) was shown to be an effective first-line treatment in advanced metastatic colorectal cancer. Sodium - folinic acid (S-FA) is a new formulation which, in contrast to CA-FA allows the simultaneous i.v. administration in combination with 5-FU in one pump. PATIENTS AND METHODS: From 1997 to 1998, 51 patients [median age 60 (range 24-77) years; 38 male, 13 female] with metastatic colorectal cancer were recruited in 5 centers to receive weekly 24-hour infusions of 5-FU (2,600 mg/m(2)) and S-FA (500 mg/m(2)) dissolved in one pump for 6 weeks as first-line treatment. The treatment cycle was repeated after a 2-week rest period. RESULTS: 1,178 administrations (median 24, range 3-54) were performed during the study. Out of 51 patients (median follow-up 20.2 months), 2 (3.9%) achieved complete remission (CR), 17 (33.3%) partial remission (PR), and 21 (41.2%) no change (NC). Progressive disease (PD) was observed in 11/51 (21.6%) patients, including 6 patients who did not complete the first cycle. Median time to tumor progression (TTP) was 8.5 months (95% CI: 5.8-11.3). 32/51 (62.7%) patients survived for more than 1 year, the median survival was reached at 16.5 months (95%CI: 10.2-22.8). Among major toxicities, NCICTC grade III/IV diarrhea occurred in 13/51 (25.4%), grade III hand-foot syndrome in 6/51 (11.7%) patients. Grade III/IV stomatitis was observed in 4/51 (7.8%), cardiac toxicity occurred in 2/51 patients (3.9%). CONCLUSION: Similar to conventional 24-hour 5-FU + CA-FA treatment, the combination with S-FA induced 37.2% objective responses with moderate toxicity. However, TTP seems favorable and the administration of S-FA is convenient, while saving costs and time for the patient in outpatient units.

Adult↗

Human thyroid carcinoma cell lines and normal thyrocytes: expression and regulation of matrix metalloproteinase-1 and tissue matrix metalloproteinase inhibitor-1 messenger-RNA and protein.

Matrix metalloproteinase-1 (MMP-1) and tissue matrix metalloproteinase inhibitor 1 (TIMP-1) play an important role in remodeling the extracellular matrix in normal and pathological processes. The effect of phorbol-myristate acetate (PMA), interleukin-1 (IL-1), and tumor necrosis factor-alpha (TNF-alpha) on MMP-1 and TIMP-1 expression was studied on highly purified thyrocytes and undifferentiated 8505 C, C 643, HTh 74, SW 1736 thyroid carcinoma cells compared with thyroid-derived fibroblasts. Messenger RNA (mRNA) levels were monitored by competitive semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) after 24 hours. Culture supernatants were assayed for free and/or complexed MMP-1 and TIMP-1 after 48 hours using enzyme-linked immunosorbent assay (ELISA) systems (detection limit: <2 ng/mL). MMP-1 and TIMP-1 mRNA were present in all cell types, although thyrocytes showed MMP-1 mRNA levels near the detection limit. 8505 C expressed MMP-1 mRNA levels of up to 10(6) times those of the other cells analyzed. PMA and IL-1 increased MMP-1 mRNA in most cell types. TIMP-1 mRNA increased after treatment with PMA in all cells except 8505 C, whereas only slight effects were shown after IL-1 stimulation. MMP-1 protein was undetectable in normal thyrocyte cultures, but was secreted spontaneously by all cell lines ([ng/mL]; C 643: 15+/-7; HTh 74: 81+/-1; SW 1736: 13+/-2; 8505 C: 2097+/-320). There was a strong correlation between levels of MMP-1 mRNA and protein (r = 0.99, p < .0001). PMA and IL-1 increased MMP-1 secretion in all cell types after 48 hours. Fibroblasts ([ng/mL] 517+/-55) and the cell lines (C 643: 142+/-48; HTh 74: 115+/-13; SW 1736: 202+/-14; 8505C: 120+/-19) secreted TIMP-1 in unstimulated cultures, whereas only a trace amount was detected in thyrocyte cultures, even after PMA treatment. IL-1 upregulated TIMP-1 secretion after 48 hours in SW 1736, HTh 74, and C 643 cells. Our data suggest that in contrast to normal thyrocytes, dedifferentiated thyroid carcinoma cell lines are potential producers of MMP-1 as well as TIMP-1. High MMP-1 or MMP-1/TIMP-1 expression may play a role in tissue invasion of undifferentiated thyroid cancer cells.

Adult↗

Effect of primary renal disease and risk factors on kidney graft survival.

The important role of immunological factors, HLA typing and pretransplant blood transfusion on improved kidney graft survival is well established. Additionally, graft survival depends on risk factors such as diabetes and age of the recipient. The effect of other clinical risk factors on graft survival was evaluated in 187 patients who received kidney transplants at our centre between 1970 and 1981. Graft survival according to the life table method and statistical analysis according to the logrank test revealed 4 main risk factors. Graft survival is significantly lower in type I diabetics and analgesic nephropathy, whereas it is better in hereditary and other renal diseases. Additional risk factors are coronary heart disease and repeated grafting. Time of dialysis before transplantation and age of the recipient showed no detrimental effect on graft survival.

Adult↗

[Long-term results after kidney transplantation].

In this investigation, our own long-term results after kidney transplantation were compared with those in literature, and the influence of recent findings on the survival rate of patients and transplants was analyzed. In 217 kidney transplant patients, the 5 and 9-year-patient survival rate was calculated at 58% and 45% respectively. The 9-year-transplant function rate was 38%. Analogous results can be derived from collective international and European statistics. The long-term patient survival rate after successful transplantation shows better results than comparable statistics of hemodialysis treatment. Analysis of the results fractionated into the years 1970 to 1974, 1975 to 1977 and 1978 to 1981 shows a continuous improvement in the survival rate of patients and transplants. This improvement of results can be attributed to the reduction of surgical complications with increasing experience and particularly to knowledge recently gained in the field of transplantation immunology (compatibility in the HLA-A/B and -DR system, preoperative blood transfusions) and immunosuppression (reduction of steroid doses, supplementary ATG and cyclosporin A medication).

Adult↗

Cyproterone acetate, testosterone, LH, FSH, and prolactin levels in plasma after intramuscular application of cyproterone acetate in patients with prostatic cancer.

Five patients with prostatic carcinoma (stages T3N0M0) were injected intramuscularly with 300 mg of cyproterone acetate (CPA) (Androcur-Depot) at weekly intervals. The concentrations of CPA, testosterone, LH, FSH, and prolactin in plasma after the first, third, and fifth injection were measured by specific radioimmunoassays. After five injections of Androcur-Depot, CPA levels were slightly higher than in previous determinations, suggesting that a balance between active substance release from the depot and excretion could be achieved after eight to twelve injections, with only slightly higher levels of active substance attained. Testosterone levels clearly were reduced after the first injection of CPA, but the lowest values were registered only after three injections. Plasma concentrations of FSH and LH were slightly diminished, whereas the prolactin level increased after CPA therapy.

Cyproterone↗

Determination of auto-antibodies against spermatozoa in experimental cryptorchism.

In 70% of the patients with unilateral retentio testis the normal descended testicle shows damage in spermiogenesis too. The formation of auto-antibodies is considered as a possible cause. In rats with artificial uni- and bilateral cryptorchism, this mechanism was examined. The presence of auto-antibodies against spermatozoa could be proven by indirect immunofluorescence. After uni- and bilateral intra-abdominal displacement of the testicles, this phenomenon takes place after the 3rd month post-operatively, shows the maximum of titers after 6 months and decreases towards the 9th month post-operatively. An animal model is presented, suitable for the study of immunological processes in unilateral gonadal diseases.

Animals↗

[Value of computer tomography in the staging of bladder and prostatic cancer].

In carcinomas of the urinary bladder we regard a humpy contour of the outer wall of the bladder as a transmural growth of the tumour, i.e. stage T4. A retraction of the wall or a plateau phenomenon was assigned to an intramural infiltration (stage T2 or T3). Contrary to the caudal lymphography in several cases changes in the nodes of the iliaca interna-group could be proved. The computer tomography seems to prove in such cases, in which the arteriography of the urinary bladder could not fulfil the expectations (9, 10). The results illustrate that by means of the methods chosen by us a delimitation of early invasive form paravesically growing vesical tumours is possible (12, 17, 18). In the classification of the carcinoma of the prostate the computer tomography does not give more essential informations in comparison to the rectal palpation, the vesiculography and the lymphography. The distinction of a normal prostate from the benign or malignant tumour tissue is not successful, since there are no specific differences in density. Particularly the tumour infiltration into the seminal vesicles could not be established early enough (7, 13). In the estimation of regional settlements of lymphatic nodes the statements are above all based on controls of the course, only a few cases could be ascertained histologically. In these cases it is necessary to keep in mind that in the computer tomography only lymphatic nodes from a diameter of 1.5-2 cm are recognizable. Since the computer tomography is a non-invasive method, it can be used for the pre- and postoperative diagnostics as well for controls of the course in tumour diseases of the lower urinary tract (2, 8, 20). However, no evidence can be made on the dignity of the spacial demands.

Aged↗