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C Sauter

Publications and source records attributed to C Sauter.

At least 37 records · Page 2Linked to original sources

A sulfate pocket formed by three GoU pairs in the 0.97 A resolution X-ray structure of a nonameric RNA.

The crystal structure of the RNA duplex [r(CGUGAUCG)dC]2 has been solved at a resolution of 0.97 A. The model has been refined to R-work and R-free of 14.88% and 19.54% for 23,838 independent reflections. The base-pairing scheme forces the 5'-rC to be excluded from the helix and to be disordered. In the crystals, the sequence promotes the formation of two GoU wobble pairs that cluster around a crystallographic threefold axis in two different ways. In the first contact type, the GoU pairs are exclusively surrounded by water molecules, whereas in the other contact type, the three amino groups of the guanine residues of the symmetry-related GoU pairs trap a sulfate ion. This work provides the first example of the interaction of a GoU pair with a sulfate ion in a helical context. Despite the negative charge on the polynucleotide backbone, the guanine amino N2 is able to attract negatively charged groups that could, in the folding of complex RNA molecules, belong to a negative phosphodiester group from a neighboring strand and, in a RNA-protein complex, to a negative carboxyl group of an aspartate or glutamate side chain.

Base Pairing↗

A prospective study of risk-adapted therapy for large cell non-Hodgkin's lymphoma with VACOP-B followed by high-dose CBV and autologous progenitor cell transplantation for high-risk patients in remission.

Several centres reported a favourable outcome after high-dose chemotherapy with autologous progenitor cell transplantation in selected patients with high-risk large cell non-Hodgkin's lymphoma in first remission. Based on these observations, we wanted to prospectively determine the outcome of a risk-adapted therapy for patients with large cell lymphoma. Patients aged 60 years or less received 12 weeks of VACOP-B chemotherapy. For high-risk patients in remission this was immediately followed by high-dose chemotherapy with cyclophosphamide, carmustine and etoposide and autologous progenitor cell transplantation. High-risk criteria were defined before the establishment of the International Index and included large cell lymphoma stage III or IV or mediastinal large lymphoma with sclerosis stage II or higher, and the presence of bulky tumours and/or an elevated LDH. 89 patients fulfilled the clinical selection criteria and were entered onto this multicentre study. 82 patients were evaluable after confirmation of large cell histology by pathology review. Of these, 51 were considered to be in the low-risk group and 31 in the high-risk group. The 3-year event-free survival for all patients was 68%. The 3-year event-free survival was 76% for the low-risk and 55% for the high-risk group (P = 0.061). Only 22/31 high-risk patients were able to receive the high-dose chemotherapy in first remission as intended. In conclusion, although our study demonstrated that a risk-adapted therapy for large cell lymphoma could be safely administered, the potential impact on outcome of the strategy chosen here is likely to be small.

Adult↗

Crystallization within agarose gel in microgravity improves the quality of thaumatin crystals.

To prevent crystals from moving in orbit and sedimenting upon their return to earth, the model protein thaumatin was crystallized in agarose gel in the Advanced Protein Crystallization Facility during the eight-day Space Shuttle mission STS-95 (November 1998). The quality of tetragonal crystals grown in microgravity was compared with that of controls prepared in parallel in the laboratory. On the basis of their diffraction properties, microgravity crystals were more ordered than crystals grown in gel on earth (the latter being, on average, better than reference crystals obtained in solution on earth). It is concluded that protein crystallization within a gel in microgravity may yield crystals of superior quality by combining the advantages of both environments. A possible explanation for the positive effect of microgravity on protein crystallization in gels involving the better quality of the nucleus is discussed.

Crystallization↗

Association of the class V myosin Myo4p with a localised messenger RNA in budding yeast depends on She proteins.

Asymmetric distribution of messenger RNAs is a widespread mechanism to localize synthesis of specific protein to distinct sites in the cell. Although not proven yet there is considerable evidence that mRNA localisation is an active process that depends on the activity of cytoskeletal motor proteins. To date, the only motor protein with a specific role in mRNA localisation is the budding yeast type V myosin Myo4p. Myo4p is required for the localisation of ASH1 mRNA, encoding a transcriptional repressor that is essential for differential expression of the HO gene and mating type switching in budding yeast. Mutations in Myo4p, in proteins of the actin cytoskeleton, and in four other specific genes, SHE2-SHE5 disrupt the daughter-specific localisation of ASH1 mRNA. In order to understand if Myo4p is directly participating in mRNA transport, we used in situ colocalisation and coprecipitation of Myo4p and ASH1 mRNA to test for their interaction. Our results indicate an association of Myo4p and ASH1 mRNA that depends on the activity of two other genes involved in ASH1 mRNA localisation, SHE2 and SHE3. This strongly suggests a direct role of Myo4p myosin as a transporter of localised mRNAs, convincingly supporting the concept of motor-protein based mRNA localisation.

DNA-Binding Proteins↗

[Green urine].

Explore the source record for details and available documents.

Adult↗

[Follow-up of tumor patients].

There are two main reasons for routine follow-up examinations after treatment of cancer patients: 1. Assessment of treatment efficacy and detection of relapse; 2. rating of drug side-effects. Routine controls can only efficiently be performed with a profound knowledge of the biology of the tumor and of the therapeutic efficacy of the available treatments. The frequency and the type of the follow-up examinations depend mainly on the curative or the palliative treatment possibilities. Examples of useless controls are mentioned. Through the prevention of unnecessary examinations the primary care physician could play an important role in the cut down of health care costs.

Adult↗

Pharmacokinetic studies of mitoxantrone and one of its metabolites in serum and urine in patients with advanced breast cancer.

OBJECTIVE: Mitoxantrone (MTO) was administered to patients with advanced breast cancer either as free MTO (f-MTO) or liposomal MTO (1-MTO). The intra- and interindividual variations in serum pharmacokinetics of MTO were analysed. In addition, the excretion of MTO and its metabolite mitoxantrone dicarboxylic acid (MTOD) in urine was determined. METHODS: The concentration of MTO was measured by high-performance liquid chromatography in serum over a period of 24 h and the amount of MTO and the metabolite MTOD excreted in urine over 18 h was determined. Pharmacokinetic parameters of f-MTO and 1-MTO were calculated. RESULTS: 1-MTO had a significantly longer half-life of distribution in the deep (third) compartment and thus a larger area under the curve (AUC) than f-MTO. No difference was found with respect to distribution in the peripheral (second) compartment. The kinetics of MTO in serum did not significantly differ between patients. In four patients repeated pharmacokinetic analyses gave superimposable results. Thus, there was no enzyme induction during therapy. By contrast, two patients with oedema had a much longer mean residence time (MRT) and AUC for MTO in serum. Despite the altered pharmacokinetics of f-MTD and 1-MTO, no toxic adverse effects occurred in these two patients. CONCLUSIONS: f-MTO and 1-MTO exhibited different distribution patterns in the deep compartment with a significantly increased half-life for 1-MTO. There is no need to monitor MTO for treatment of breast cancer patients with f-MTO. In patients with oedema, the MRT of MTO is prolonged. The clinical relevance of this observation is as yet unclear.

Adult↗

[Quality of treatment in operable breast carcinoma. Comparison of the years before 1987, 1987-1990 and 1991-1994].

BACKGROUND: Has progress in the treatment of breast cancer been translated into routine practice? What can be further ameliorated? We present a first step in quality assurance by examining the quality of care in early-stage breast cancer during recent years. METHODS: Retrospective analysis of actual care in 300 patients with operable invasive breast cancer. Analysis and comparison of treatment in 3 time-periods based on date of diagnosis (before 1987, 1987-1991, 1991-6/1994). RESULTS: Staging, surgical treatment and histopathological analysis have become more complete over these years. There is, however, no tendency to diagnose smaller tumors in our series. The percentage of patients undergoing breast-conserving surgery has not increased since 1987. Overall, 25% of cancers were treated by breast-conserving surgery. The rate of ipsilateral breast recurrences after breast-conserving surgery was 19% if the breast was irradiated, and 67% when radiation had been omitted (median follow-up 50 months). Adjuvant systemic therapy is now given to many node negative patients. Combined adjuvant therapy (endocrine plus chemotherapy) was rarely used. Early consultation of medical oncology has increased in recent years. CONCLUSION: Progress in the treatment of early-stage breast cancer has only partially been translated into clinical practice. To ensure that treatment decisions conform to the most recent standards, quality controls are necessary. The simplest form of quality control is a multidisciplinary approach, which should be used early, in every case, and if necessary, repeatedly.

Adult↗

[Chemotherapy of gastrointestinal carcinomas and non-small-cell pulmonary carcinoma: a controversy].

Patients with metastatic gastrointestinal cancers and metastatic non-small cell lung cancer present an important challenge in medical oncology and palliative care. Symptoms caused by tumor progression should undoubtedly be treated. The management of asymptomatic patients, however, is still controversial. A clinical decision on whether an asymptomatic patient should be treated with chemotherapy at an early or at a late stage in the evolution of the disease must often be reached on an individual basis. Ongoing clinical research to improve treatment results is still urgently needed. Research programs should aim at (a) evaluating new drugs and (b) testing new multi-modal treatment strategies.

Antineoplastic Agents↗