Effects of sodium valproate on the chromatin of Triatoma infestans (Klug, 1834) (Hemiptera, Reduviidae) under in vitro culture conditions.

Sodium valproate (VPA) is a classic anticonvulsive, a histone deacetylase inhibitor, and a chromatin remodeling inducer. When injected into specimens of Triatoma infestans, a vector of Chagas disease, VPA affects the chromatin supraorganization of chromocenter heterochromatin in only a few cells of the Malpighian tubules. To test whether this result was explained by the inaccessibility of all of the organ's cells to the drug, we investigated the nuclear phenotypes and global acetylation of lysine 9 in histone H3 (H3K9ac) in Malpighian tubules cultivated in vitro for 1-24 h in the presence of 0.05 mM-1 mM VPA. The present results revealed that the chromatin decondensation event in the chromocenter body, which was detected only under low VPA concentrations up to a 4-h treatment, was not frequent during organ culture, similar to the results for injected insects. Cultivation of T. infestans Malpighian tubules in vitro for 24 h revealed inadequate for cell preservation even in the absence of the drug. Immunofluorescence signals for H3K9ac following VPA treatment showed a slightly increased intensity in the euchromatin, but were never detected in the chromocenter bodies, except with great intensity at their periphery, where the 18S rDNA is located. In conclusion, when VPA affects the chromocenter heterochromatin in this animal cell model, it occurs through a pathway that excludes a classic global H3K9ac mark. Investigation of nonhistone proteins associated with histone methylation marks is still required to further explain the differential response of T. infestans chromatin to VPA.

Satellite Telemetry and Image Reception with Software Defined Radio Applied to Space Outreach Projects in Brazil.

Software Defined Radio (SDR) uses a processor, a special receiver and software that play the main parts of the receiver (mixer, filters, amplifiers, modulators, demodulators, etc.) and it is quite advantageous for its flexibility and compact size as it reduces the amount of hardware components while adapting for different needs. This work briefly presents the SDR concept and approach for obtaining satellite telemetries and imagery in the context of different modulation schemes, link budget requirements and different satellites types. Two case studies are presented for supporting affordable ground segment and promoting satellites projects in Brazil. Reception from the 1st Brazilian picosatellite, Tancredo-1, with specific software developed, UbaTM is presented for obtaining satellite raw telemetries, convert them to engineering value and friendly present on user screen. A series of support software packages are then introduced so that one can pipeline various operations and automate tasks in the ground station. Finally, a second study case was performed in order to receive NOAA class satellites imagery over VHF band and decoded by specific software freely available. Using the proposed SDR approach, it can adapt to projects mainly those with a limited budget and outreach for major inclusion on space topics in Brazil.