Homarus Americanus Stomatogastric Nervous System Dissection

With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the activity of interest and are accessible and amenable to experimental methods. The stomatogastric nervous system (STNS) of the American lobster (Homarus americanus; also know was the Atlantic or Maine lobster) has been established as a model system for studying rhythm generating networks and neuromodulation of networks. The STNS consists of 3 anterior ganglia (2 commissural ganglia and an oesophageal ganglion), containing modulatory neurons that project centrally to the stomatogastric ganglion (STG). The STG contains approximately 30 neurons that comprise two central pattern generating networks, the pyloric and gastric networks that underlie feeding behaviors in crustaceans^1,2. While it is possible to study this system in vivo³, the STNS continues to produce its rhythmic activity when isolated in vitro. Physical isolation of the STNS in a dish allows for easy access to the somata in the ganglia for intracellular electrophysiological recordings and to the nerves of the STNS for extracellular recordings. Isolating the STNS is a two-part process. The first part, dissecting the stomach from the animal, is described in an accompanying video article⁴. In this video article, fine dissection techniques are used to isolate the STNS from the stomach. This procedure results in a nervous system preparation that is available for electrophysiological recordings.     

Circular Thin-layer Chromatography of Oligosaccharides

The physicochemical properties and chemical constituents of the blue protein from rice bran were investigated. The blue protein was a copper-containing glycoprotein, the molecular weight of which was found to be 18,300 Daltons by the sedimentation equilibrium method assuming the partial specific volume 0.72 cm³ g^?1. The hexose and pentose contents were 5.49 and 4.01 g per 100 g protein respectively. The copper content was 0.38% which corresponded to 1.09 atoms per one molecule of the protein. The electron spin resonance spectrum showed that the copper was in a cupric state. The standard oxidation-reduction potential of the copper was found to be +275 mV at 20°C and at pH 7.39. The visible and near infrared absorption maxima were found at 450, 600 and 890 mμ, and the 450 mμ band was optically active in the optical rotatory dispersion exhibiting a large Cotton effect.     

Injury Delays Stem Cell Apoptosis after Radiation in Planarians

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Synaptic Connectivity between the Cortex and Claustrum Is Organized into Functional Modules

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Calcium Wave Promotes Cell Extrusion

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Cancer‐upregulated gene 2 (CUG2) overexpression induces apoptosis in SKOV‐3 cells

Cancer‐upregulated gene 2 (CUG2) was originally identified as a potential oncogene commonly up‐regulated in various human cancers. Recently, CUG2 was also identified as a new member of a centromere protein complex, important in the formation of a functional kinetochore complex. Presently, we report the pro‐apoptotic effect of CUG2 when this gene was overexpressed in the SKOV‐3 human ovarian cancer cell line. Apoptotic cell death mediated by CUG2 overexpression was independently demonstrated using cell viability determination, flow cytometry analysis, chromosome fragmentation assay, and the cleavage of the death substrate poly(ADP‐ribose) polymerase. Moreover, activation of caspase‐3 and ‐8 and the cytoplasmic translocation of mitochondrial cytochrome c were evident upon CUG2 expression. Apoptotic cell death was also observed during early development of zebrafish when CUG2 was overexpressed in zebrafish embryo. We propose that high expression of CUG2 induces apoptotic cell death. Copyright © 2010 John Wiley & Sons, Ltd.     

The novel ruthenium—γ‐linolenic complex [Ru2(aGLA)4Cl] inhibits C6 rat glioma cell proliferation and induces changes in mitochondrial membrane potential,increased reactive oxygen species generation and apoptosis in vitro

The present study reports the synthesis of a novel compound with the formula [Ru₂(aGLA)4Cl] according to elemental analyses data, referred to as Ru₂GLA. The electronic spectra of Ru₂GLA is typical of a mixed valent diruthenium(II,III) carboxylate. Ru₂GLA was synthesized with the aim of combining and possibly improving the anti‐tumour properties of the two active components ruthenium and γ‐linolenic acid (GLA). The properties of Ru₂GLA were tested in C6 rat glioma cells by analysing cell number, viability, lipid droplet formation, apoptosis, cell cycle distribution, mitochondrial membrane potential and reactive oxygen species. Ru₂GLA inhibited cell proliferation in a time and concentration dependent manner. Nile Red staining suggested that Ru₂GLA enters the cells and ICP‐AES elemental analysis found an increase in ruthenium from <0.02 to 425 mg/Kg in treated cells. The sub‐G1 apoptotic cell population was increased by Ru₂GLA (22 ± 5.2%) when analysed by FACS and this was confirmed by Hoechst staining of nuclei. Mitochondrial membrane potential was decreased in the presence of Ru₂GLA (44 ± 2.3%). In contrast, the cells which maintained a high mitochondrial membrane potential had an increase (18 ± 1.5%) in reactive oxygen species generation. Both decreased mitochondrial membrane potential and increased reactive oxygen species generation may be involved in triggering apoptosis in Ru₂GLA exposed cells. The EC₅₀ for Ru₂GLA decreased with increasing time of exposure from 285 µM at 24 h, 211 µM at 48 h to 81 µM at 72 h. In conclusion, Ru₂GLA is a novel drug with antiproliferative properties in C6 glioma cells and is a potential candidate for novel therapies in gliomas. Copyright © 2009 John Wiley & Sons, Ltd.     

Polysaccharides derived from Balanophora polyandra significantly suppressed the proliferation of ovarian cancer cells through P53‐mediated pathway

Ovarian cancer (OC) is ranked the first among the cancers threatening women's health. It attracts tremendous attention of cancer researchers because of its extremely high mortality rate. Recent studies have indicated that traditional herbal medicines (THMs) can play a pivotal role in cancer prevention and treatment. THMs are gaining popularity as a source of anti‐cancer agents. The plant of Balanophora polyandra, which has been used as a traditional herbal medicine, has been known for exhibiting potential haemostatic, analgesic, anti‐inflammatory and anti‐cancer properties. However, few studies on inhibitory effect of B. polyandra on OC have been performed. In the present study, we found that B. polyandra polysaccharides (BPP) induced cell cycle arrest at S phase, triggered apoptosis and inhibited migration and invasion of OC cells. Furthermore, we also found that there was a potential and close relationship between BPP and P53‐mediated pathway. Overall, these findings suggest that BPP can be a potential therapeutic agent for the treatment of OC.