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The SAC8.5, a low-cost Peltier-cooled black and white 8-bit CCD camera for astronomy, was evaluated for its use in imaging microscopy. Two camera–microscope configurations were used: an epifluorescence microscope (Nikon Eclipse TE2000-U) and a bottom port laser scanning confocal microscope system (Zeiss LSCM 510 META). Main advantages of the CCD camera over the currently used photomultiplier detection in the scanning setup are fast image capturing, stable background, an improved signal-to-noise ratio and good linearity. Based on DAPI-labelled Chinese Hamster Ovarian cells, the signal-to-noise ratio was estimated to be 4 times higher with respect to the currently used confocal photomultiplier detector. A linear relationship between the fluorescence signal and the FITC-inulin concentrations ranging from 0.05 to 1.8 mg mL−1 could be established. With the SAC8.5 CCD camera and using DAPI, calcein-AM and propidium iodide we could also distinguish between viable, apoptotic and necrotic cells: exposure to CdCl2 caused necrosis in A6 cells. Additional examples include the observation of wire-like mitochondrial networks in Mito Tracker Green-loaded Madin–Darby canine kidney cells. Furthermore, it is straightforward to interface the SAC8.5 with automated shutters to prevent rapid fluorophore photobleaching via easy to useastrovideo software. In this study, we demonstrate that the SAC8.5 black and white CCD camera is an easy-to-implement and cost-conscious addition to quantitative fluorescence microfluorimetry on living tissues and is suitable for teaching laboratories. [ABSTRACT FROM AUTHOR]

Crude trifluoroacetic acid extracts were prepared from different body parts of the forest ant, Formica polyctena Foerster, Hymenoptera, Formicidae, and the honeybee, Apis mellifera carnica Pollmann, Hymenoptera, Apidae. Extracts were prepurified by means of solid phase extraction over reversed-phase cartridges. The effects of the resulting fractions on fluid secretion rates were tested on single preparations of ant Malpighian tubules. Diuretic and antidiuretic factors were shown to be present. High-performance liquid chromatography allowed for the identification of a diuretic factor from the bee-head extract which had a similar elution profile to a previously purified diuretic peptide from ant-head extracts. An antidiuretic factor was also identified from the bee abdominal extract. Similar to an antidiuretic peptide, which was purified from ant abdominal extracts, this antidiuretic factor inhibited fluid secretion and depolarized the transepithelial potential of ant Malpighian tubules. [ABSTRACT FROM AUTHOR]

In previous studies exposing animals to Cd caused oxidative stress and kidney damage. Mostly high doses were applied, often by injection. In the present study mice were exposed up to 23 weeks to low Cd concentrations (10 and 100 mg CdCl2/l) in the drinking water. Antioxidant gene expression levels as well as glutathione, ascorbate and lipid peroxidation levels were measured. Metallothionein 1 and 2 were upregulated from 1 week of exposure on. An early induction of the Prdx2 gene suggested that peroxiredoxin might be involved in the early response as well. After 8 weeks Cd reduced antioxidant expression of Bcl2, Prdx2 and Sod1 which might indicate a toxic effect. No significant effect was seen on lipid peroxidation however, and the overall redox status remained in balance throughout the whole experiment. Levels of reduced glutathione and ascorbate and of transcription of Sod2 remained stable. This suggested that the energy maintenance in mitochondria was under control. A second response was observed after 23 weeks. Interestingly, the expression of renal NADPH oxidase 4 (Nox4) increased. Nox4 has not been studied yet in Cd nephrotoxicity. The antioxidants catalase, glutathione peroxidase 4 and heme oxygenase 1 also responded. In conclusion our study reveals a two-step oxidative stress response in the kidney. Clearly the kidney was in control of Cd-induced oxidative stress after exposure to low Cd concentrations. [ABSTRACT FROM AUTHOR]