Parazoanthoxanthin A is a fluorescent yellow nitrogenous pigment of the group of zoanthoxanthins, which show a broad range of biological activity. These include, among others, the ability to bind to DNA. In this study we have used a variety of spectroscopic (intrinsic fluorescence emission and UV-spectroscopy) and hydrodynamic techniques (viscometry) to characterize in more detail the binding of parazoanthoxanthin A to a variety of natural and synthetic DNA duplexes in different buffer conditions. Our results reveal the following five significant features: (i) Parazoanthoxanthin A exhibits two modes of DNA binding: One binding mode exhibits properties of intercalation, while the second binding mode is predominantly electrostatic in origin. (ii) The apparent binding "site size" for parazoanthoxanthin A near physiological salt concentration (100 mM NaCl) is in the range of 7 +/- 1 base pairs for natural genomic DNA duplexes (calf thymus and salmon testes DNA) and alternating synthetic polynucleotides (poly[d(AT)]. poly[d(AT)] and poly[d(GC)]. poly[d(GC)]). A slightly larger apparent binding site size of 9 +/- 1 bp was obtained for parazoanthoxanthin A binding to the synthetic homopolymer poly[d(A)]. poly[d(T)]. (iii) Near physiological salt concentration (100 mM NaCl) parazoanthoxanthin A binds with the same approximate binding affinity of 2-5 x 10(5) M(-1) to all DNA polymers studied. (iv) At low salt concentration, parazoanthoxanthin A preferentially binds alternating poly[d(AT)]. poly[d(AT)] and poly[d(GC)]. poly[d(GC)] host duplexes. (v) Parazoanthoxanthin A inhibits DNA polymerase in vitro.

This paper discusses the stability of TCP. More precisely, the stationary behavior of the congestion window process is analyzed based on the measured real Internet traffic (bulk data transfer, FTP of large files). Appropriate algorithm approximating the actual congestion window is presented, and statistical methods to analyze the data are discussed in detail: change-point detection, distribution testing and parameter estimation. It has been shown that the distribution of the congestion window process during stable periods has a bell-like shape and can be approximated by a normal distribution. A number of interesting observations during the study are depicted and explained. Finally, possibilities for building reliable and robust models for the TCP protocol in the future, are discussed.

OBJECTIVE To study the short-term effects of physical therapy (ice massage or wax packs, thermal baths, and faradic hand baths) and exercise therapy on the rheumatoid hand. METHODS The effect of individual physical therapy and exercise therapy programs was evaluated in 50 randomly selected rheumatoid arthritis inpatients (38 women and 12 men). Mean patient age (+/- SD) was 47.94 +/- 11.22 years, and mean disease duration was 5.04 +/- 4.80 years. The control group consisted of 50 randomly selected rheumatoid arthritis outpatients (37 women and 13 men; mean age 48.46 +/- 10.65 years, mean duration of disease 5.23 +/- 4.89 years) who at the time of the investigation were not receiving any physical or exercise therapy. The clinical indices used for evaluation of inflammation included erythrocyte sedimentation rate (ESR), pain intensity, proximal interphalangeal (PIP) joint size, and Ritchie articular index. Hand grip strength, palmar tip-to-tip and key pinch finger strength, finger range of motion, and activities of daily living (ADL) were the parameters used to assess the functional hand status. The study was single-blinded and of 3 weeks duration. RESULTS In the physical therapy treated group, there was an improvement for most of the observed indices from baseline parameters that achieved statistical significance (P < 0.01 and P < 0.005) after the 3-week study period. ESR and PIP joint size improved clinically but failed to reach statistical significance. Patients had a more significant improvement in hand pain, joint tenderness, and ADL score (P < 0.005) than in range of motion (P < 0.01). All parameters in the control group slightly deteriorated over the study period. CONCLUSION At least in the short term, physical and, particularly, exercise therapy produce a favorable improvement in the functional status of the rheumatoid hand.