Gene network shaping of inherent noise spectra.

Recent work demonstrates that stochastic fluctuations in molecular populations have consequences for gene regulation. Previous experiments focused on noise sources or noise propagation through gene networks by measuring noise magnitudes. However, in theoretical analysis, we showed that noise frequency content is determined by the underlying gene circuits, leading to a mapping between gene circuit structure and the noise frequency range. An intriguing prediction from our previous studies was that negative autoregulation shifts noise to higher frequencies where it is more easily filtered out by gene networks--a property that may contribute to the prevalence of autoregulation motifs (for example, found in the regulation of approximately 40% of Escherichia coli genes). Here we measure noise frequency content in growing cultures of E. coli, and verify the link between gene circuit structure and noise spectra by demonstrating the negative autoregulation-mediated spectral shift. We further demonstrate that noise spectral measurements provide mechanistic insights into gene regulation, as perturbations of gene circuit parameters are discernible in the measured noise frequency ranges. These results suggest that noise spectral measurements could facilitate the discovery of novel regulatory relationships.

[Evaluation of surgical treatment results in patients with differentiated thyroid cancer from materials in the Oncologic Institute in Gliwice]. / Ocena wyników leczenia operacyjnego chorych na zróznicowane raki tarczycy w materiale Instytutu Onkologii w Gliwicach.

The optimal surgical treatment for patients with differentiated thyroid carcinoma is still controversial and discussed. The aim of this study was to analyze the effectiveness of treatment in differentiated thyroid carcinoma, to establish the prognostic value of histopathological type, clinical advancement, the extent of surgery and to estimate the therapeutic benefit rate of the radical approach. The randomized group of 768 patients with differentiated thyroid carcinoma, aged between 16 to 40 (median age 44), treated in Oncology Center Institute in Gliwice between 1986 and 1997 were analyzed. They were operated in different surgical clinics in Poland. The primary total thyroidectomy was performed in 153 of patients (20%), the secondary radical operation in 474 (62%). 136 persons were operated by less radical approach. Cervical lymph node metastases were observed in 26% of patients. Distant metastases occurred in 8% of cases. 610 persons were treated with 131I. All patients were administered hormonal therapy to suppress TSH. Locoregional recurrence occurred in 7.5% of patients. Complete remission was observed in 71.5% of persons (548 patients). The influence of distant metastases lymph node metastases and tumor size on the long-term prognosis was analyzed in univariate statistic analysis. There were no differences in survival in patients with papillary and follicular carcinoma. The 10-year survival was statistically significantly longer in patients who underwent radical surgical treatment (92%) than after non-total thyroidectomy (80%). Despite the relatively high risk of surgical complications the benefits of the radical approach were significant.