Cytologic diagnosis of a metastatic oligodendroglioma in a pleural effusion. A case report

BACKGROUND: Extraneural metastasis of oligodendroglioma is extremely rare and is diagnosed primarily by biopsy or autopsy and very occasionally by fine needle cytologic examination. We report a case of metastatic oligodendroglioma diagnosed by cytologic examination of a pleural effusion. Such a diagnosis has not been reported before. CASE: A 64-year-old woman developed anemia and bilateral pleural effusion 7 years after an operation for an oligodendroglioma over the left frontal lobe. Cytologic examination of the pleural effusion showed aggregates of atypical polygonal cells containing round, hyperchromatic nuclei and scanty, granular cytoplasm in Liu's and Papanicolaou stain and cell blocks. Immunohistochemical staining of the tumor cells revealed a positive reaction for antibodies to glial fibrillary acidic protein, S-100 and Olig2. Pleural biopsy confirmed the cytologic diagnosis of pleural effusion. A pathologic fracture of the right humeral and femoral bones was noted 1 month later, and the specimen also showed infiltrating oligodendroglioma cells in bone tissue. CONCLUSION: To the best of our knowledge, this is the first metastatic oligodendroglioma diagnosed by pleural cytology. Fine needle cytology can provide a reliable and rapid way to detect an extracranial metastatic oligodendroglioma in different organs.     

Visible-Light-Induced Bactericidal Activity of a Nitrogen-Doped Titanium Photocatalyst against Human Pathogens

The antibacterial activity of photocatalytic titanium dioxide (TiO₂) substrates is induced primarily by UV light irradiation. Recently, nitrogen- and carbon-doped TiO₂ substrates were shown to exhibit photocatalytic activities under visible-light illumination. Their antibacterial activity, however, remains to be quantified. In this study, we demonstrated that nitrogen-doped TiO₂ substrates have superior visible-light-induced bactericidal activity against Escherichia coli compared to pure TiO₂ and carbon-doped TiO₂ substrates. We also found that protein- and light-absorbing contaminants partially reduce the bactericidal activity of nitrogen-doped TiO₂ substrates due to their light-shielding effects. In the pathogen-killing experiment, a significantly higher proportion of all tested pathogens, including Shigella flexneri, Listeria monocytogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Streptococcus pyogenes, and Acinetobacter baumannii, were killed by visible-light-illuminated nitrogen-doped TiO₂ substrates than by pure TiO₂ substrates. These findings suggest that nitrogen-doped TiO₂ has potential application in the development of alternative disinfectants for environmental and medical usages.     

The effect of ultrasound stimulation versus bioreactors on neocartilage formation in tissue engineering scaffolds seeded with human chondrocytes in vitro

Pulsed ultrasound (1 MHz, 67 mW/cm(2) Ispta, and 10 min/day) promoted cell proliferation and matrix deposition in low-density 2D ( approximately 6 x 10(3)cells/cm(2)) as well as 3D ( approximately 4 x 10(6)cells/cm(3)) chondrocyte cultures. The beneficial effect of ultrasound on neocartilage formation only last 28 days, shorter than that of bioreactors.     

Enhanced nuclear factor-kappa B-associated Wnt-1 expression in hepatitis B- and C-related hepatocarcinogenesis: identification by functional proteomics

Summary Chronic infections with hepatitis B and C viruses (HBV and HCV) are etiologically linked to hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). Both viruses may induce activation of nuclear factor-kappa B (NF-κB) in hepatocytes that plays a crucial role in the regulation of cell growth and apoptosis. Functional proteomics analysis of proteins associated with NF-κB signaling complexes in both viruses-related HCC tumor and non-tumor tissues may disclose possible common mechanisms in hepatocarcinogenesis. By functional proteomics, we analyzed proteins associated with NF-κB-signaling complexes in four-paired human HCC tumor and non-tumor tissues from HBV- and HCV-infected patients, respectively, and in one-paired tissue with dual viral infection. The quantity of NF-κB-associated proteins was semi-quantitatively measured by protein spot intensity on the gels of two-dimensional polyacrylamide gel electrophoresis. The results showed that overexpression of NF-κB-associated Wnt-1 protein in tumor part was detected in the␣majority of HBV- and HCV-infected HCC samples. These data suggest that enhanced expression of NF-κB-associated Wnt-1 protein might be a mechanism of hepatocarcinogenesis common to HBV- and HCV-infected patients. NF-κB signaling pathway and Wnt-1 protein could be potential targets for designing highly effective therapeutic agents in treating HCC and for chemoprevention of hepatocarcinogenesis.     

A DNA Vaccine Encoding a Codon-Optimized Human Papillomavirus Type 16 E6 Gene Enhances CTL Response and Anti-tumor Activity

Summary The HPV oncoproteins E6 and E7 are consistently expressed in HPV-associated cancer cells and are responsible for their malignant transformation. Therefore, HPV E6 and E7 are ideal target antigens for developing vaccines and immunotherapeutic strategies against HPV-associated neoplasms. Recently, it has been demonstrated that codon optimization of the HPV-16 E7 gene resulted in highly efficient translation of E7 and increased the immunogenicity of E7-specific DNA vaccines. Since vaccines targeting E6 also represent an important strategy for controlling HPV-associated lesions, we developed a codon-optimized HPV-16 E6 DNA vaccine (pNGVL4a-E6/opt) and characterized the E6-specific CD8⁺ T cell immune responses as well as the protective and therapeutic anti-tumor effects in vaccinated C57BL/6 mice. Our data indicated that transfection of human embryonic kidney cells (293 cells) with pNGVL4a-E6/opt resulted in highly efficient translation of E6. In addition, vaccination with pNGVL4a-E6/opt significantly enhanced E6-specific CD8⁺ T cell immune responses in C57BL/6 mice. Mice vaccinated with pNGVL4a-E6/opt are able to generate potent protective and therapeutic antitumor effects against challenge with E6-expressing tumor cell line, TC-1. Thus, DNA vaccines encoding a codon-optimized HPV-16 E6 may be a promising strategy for improving the potency of prophylactic and therapeutic HPV vaccines with potential clinical implications.     

Modulation of testicular receptor 4 activity by mitogen-activated protein kinase-mediated phosphorylation

Testicular receptor 4 (TR4) is an orphan member of the nuclear receptor superfamily. Despite the lack of identified ligands, its functional role has been demonstrated both in animals and cell cultures. However, it remains unclear how the biological activity of TR4 is regulated without specific ligands. In this study, we showed that in the absence of specific ligands the activity of TR4 could be modulated by mitogen-activated protein kinase (MAPK)-mediated phosphorylation of its activation function 1 (AF-1) domain. A mass spectrometry-based proteome analysis of TR4 expressed in insect cells revealed three phosphorylation sites in its AF-1 domain, specifically on Ser(19), Ser(55), and Ser(68). Site-directed mutagenesis studies demonstrated the functionality of phosphorylation on Ser(19) and Ser(68) but not Ser(55). We also demonstrated that MAPK-mediated phosphorylation of the AF-1 domain rendered TR4 a repressor, mediated through the preferential recruitment of corepressor RIP140. Dephosphorylation of its AF-1 made TR4 an activator due to its selective recruitment of coactivator, P300/cyclic AMP-responsive element binding protein-binding protein-associated factor (PCAF). The biological effects were validated by using the wild type TR4 and its constitutive negative (dephosphorylated) and constitutive positive (phosphorylated) mutants in the studies of regulation of its natural target gene, apoE. This study uncovered, for the first time, a ligand-independent mechanism underlying the biological activity of TR4 that was mediated by MAPK-mediated receptor phosphorylation of AF-1 domain.     

Determination of tetrodotoxin in human urine and blood using C18 cartridge column, ultrafiltration and LC-MS

Six fishermen were victims (including one death) of food poisoning from unknown fish on their boat in central Taiwan Strait, in April 2001. The symptoms were like those of tetrodotoxin (TTX) poisoning. As there was no remaining fish, a new protocol was developed to determine TTX in the urine and blood of the victims. The urine and blood samples were cleansed using a C18 Sep-Pak cartridge column, and the toxin was extracted by methanol. The eluate was filtered through a microcentrifuge filter. The filtrate was freeze-dried, dissolved in distilled water, and determined by LC-MS. The recovery was more than 88.9%. The detection limit was 15.6 nM. A linear relationship between response and concentration was obtained between 93.75 and 9375 nM of TTX. It was shown that the urine and blood of the victims contained TTX. The range of TTX was 4.5-40.6 nM in blood and 47-344 nM in urine. Judging from the symptoms of the victims and the experimental data, the causative agent of the food poisoning was identified as TTX.     

Determination of acteoside in Cistanche deserticola and Boschniakia rossica and its pharmacokinetics in freely-moving rats using LC-MS/MS

A sensitive LC-MS/MS method with a simple solid-phase extraction for the determination of acteoside in rat plasma and tissue homogenates was established for the investigation of bioavailability and brain distribution in freely-moving rats. Acteoside in Cistanche deserticola and Boschniakia rossica was also determined. Acteoside and internal standard were separated on a RP-select B column (125mmx4.6mm i.d., particle size 5microm). The mobile phase consisted of 35% methanol and 65% acetic acid-water (1:100, v/v) at a flow-rate of 1mL/min. Acteoside and the internal standard were monitored using the multiple-reaction monitoring (MRM) mode at m/z transitions of 623-->161 and 609-->301, respectively. The acteoside content was 38.4+/-2.4mg/kg (n=3) for B. rossica, which is obviously lower than 21134.2+/-805.5mg/kg (n=3) of C. deserticola. The protein binding in rat plasma was 75.5+/-1.8%. The brain distribution result indicated that acteoside was evenly distributed in brain tissues (brain stem, cerebellum, the rest of the brain, cortex, hippocampus and striatum) which was about 0.45-0.68% of that in plasma (4.5+/-0.5microg/mL) after 15min of acteoside administration (10mg/kg, i.v.). After acteoside was given (3mg/kg, i.v.; 100mg/kg, p.o.), the oral bioavailability (AUC(p.o.)/dose(p.o.))/(AUC(i.v.)/dose(i.v.)) was only 0.12%.