Toxin and species identification of toxic octopus implicated into food poisoning in Taiwan.

A food poisoning incident due to ingestion of unknown octopus occurred in Taipei in December, 2010. The serum and urine from victims (male 38 and 43 years old) were collected, determined the toxicity, and identified tetrodotoxin (TTX) by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS). It was found that only urine contained the trace of TTX. Then, two retained specimen (one without blue ring in the skin and another with small blue ring in the skin) were collected from victims and examined for the toxicity and toxin. Meanwhile, 6 specimens of octopus without blue ring in the skin and 4 specimens of octopus with blue ring in the skin were re-collected from the market. Both retained octopus samples were found to contain TTX. However, re-collected market's octopus without blue ring in the skin did not show to contain TTX the and was identified as Octopus aegina by using the analysis of cytochrome b gene (Cyt b) and cytochrome c oxidase subunit I gene (COI). Only octopus with blue ring in the skin contained TTX and was identified as Hapalochlaena fasciata by using the analysis of Cyt b and COI. Therefore, this octopus food poisoning was caused by toxic octopus H. fasciata and the causative agent was TTX.

Sodium valproate induces mitochondria-dependent apoptosis in human hepatoblastoma cells.

BACKGROUND: Sodium valproate inhibits proliferation in neuroblastoma and glioma cells, and inhibits proliferation and induces apoptosis in hepatoblastoma cells. Information describing the molecular pathways of the antitumor effects of sodium valproate is limited; therefore, we explored the mechanisms of action of sodium valproate in the human hepatoblastoma cell line, HepG2. METHODS: The effects of sodium valproate on the proliferation of HepG2 cells were evaluated by the Walsh-schema transform and colony formation assays. Sodium valproate-induced apoptosis in HepG2 cells was investigated with fluorescence microscopy to detect morphological changes; by flow cytometry to calculate DNA ploidy and apoptotic cell percentages; with Western blotting analyses to determine c-Jun N-terminal kinases (JNK), p-JNK, Bcl-2, Bax, and caspase-3 and -9 protein expression levels; and using JC-1 fluorescence microscopy to detect the membrane potential of mitochondria. Statistical analyses were performed using one-way analysis of variance by SPSS 13.0 software. RESULTS: Our results indicated that sodium valproate treatment inhibited the proliferation of HepG2 cells in a dose-dependent manner. Sodium valproate induced apoptosis in HepG2 cells as it: caused morphologic changes associated with apoptosis, including condensed and fragmented chromatin; increased the percentage of hypodiploid cells in a dose-dependent manner; increased the percentage of annexin V-positive/propidium iodide-negative cells from 9.52% to 74.87%; decreased JNK and increased phosphate-JNK protein expression levels; reduced the membrane potential of mitochondria; decreased the ratio of Bcl-2/Bax; and activated caspases-3 and -9. CONCLUSION: Sodium valproate inhibited the proliferation of HepG2 cells, triggered mitochondria-dependent HepG2 cell apoptosis and activated JNK.

[Antisense oligonucleotides targeting protein kinase C alpha inhibits the proliferation of A549 cells].

OBJECTIVE: To investigate the effects of antisense oligonucleotides (ASODN) targeting protein kinase C alpha (PKCalpha) on the proliferation of A549 cells. METHODS: PKCalpha ASODN and random oligonucleotides (RODN) were transfected into A549 cells mediated by polyethyleneimine, and the proliferation and clone formation of A549 cells were detected by CCK-8 and clone formation assay, respectively. The expression of PKCalpha in the transfected cells was analyzed by RT-PCR and Western blotting. RESULTS: Compared with those in the control group, PEI group and PEI-RODN group, the proliferation and clone formation of A549 cells treated with ASODN targeting PKCalpha were significantly inhibited (P<0.05). The expressions of PKCalpha mRNA and protein in PKCalpha ASODN-transfected A549 cells were significantly lower than those in the other 3 groups (P<0.05). CONCLUSION: The PKCalpha ASODN mediated by PEI down-regutates the expression of PKCalpha gene and suppress the proliferation and clone formation of A549 cells.