Severity of histopathologic abnormalities and in vivo epileptogenicity in the in utero radiation model of rats is dose dependent

PURPOSE: Malformations of cortical development (MCDs) are a frequent cause of refractory epilepsy in humans. The in utero radiation model in rats shares many clinical and histopathologic characteristics with human MCDs. Previous studies reported the presence of clinical seizures in radiated rats, but also suggested a dose-dependent differential effect. METHODS: Time-pregnant Sprague-Dawley rats were irradiated on embryonic day E17 with 100 cGy (low dose), 145 cGy (medium dose), 175 cGy (high dose), or were left untreated. Their adult litters were implanted with bifrontal epidural and hippocampal depth electrodes and underwent long-term video-EEG monitoring. After 2 weeks of monitoring, the animals were killed and their brains processed for histological studies. RESULTS: Spikes were most frequently found in the rats that were subjected to low- and medium-dose radiation at E17 and were less frequently seen in the animals that were subjected to high-dose radiation. No interictal spikes were found in any of the control animals. Seizures were recorded in three of five animals of the medium-dose group. Histological studies showed a dose-dependent decrease in cortical thickness as well as an increase of cortical and hippocampal disorganization. CONCLUSIONS: In vivo epileptogenicity in radiated animals was present only in mild or moderate MCD. No in vivo epileptogenicity was seen in severe radiation-induced MCD.     

Value of transcatheter arterial embolization with coils and n-butyl cyanoacrylate for long-term hepatic arterial infusion chemotherapy

PURPOSE: To assess the value of transcatheter arterial embolization (TAE) of splanchnic arterial branches to allow continuous application of repeat hepatic arterial infusion chemotherapy (HAIC). MATERIALS AND METHODS: In 128 patients with unresectable advanced liver cancer, percutaneous implantation of a port catheter system and TAE of splanchnic arteries with coils and/or n-butyl cyanoacrylate (NBCA) were performed. Parameters included (a) methods selected for catheter placement; (b) embolic materials used (coils and/or NBCA, number of coils, administration rate of NBCA-iodized oil) for TAE of splanchnic arteries, details of embolized arteries, and frequency of recanalization; (c) ability to prevent gastrointestinal symptoms by avoiding inflow of anticancer drugs into extrahepatic adjacent organs and to maintain distribution of contrast agents in liver, as well as management of difficulties encountered; (d) complications related to catheter system implantation or to long-term HAIC and management of such complications; and (e) final success in performing scheduled HAIC while maintaining distribution over liver via a single route without gastrointestinal symptoms caused by inflow of anticancer drugs. Fisher exact test was used to compare recanalization rate between coil-embolized and NBCA- or NBCA-coil-embolized arteries, and frequency of heterogeneously poor distribution was compared between patients with single and those with multiple hepatic arteries. RESULTS: Embolization was successful during first catheterization in 326 arteries and during follow-up in 10. In 119 (93.0%) of 128 patients, repeat HAIC was effective until death or the time of this writing (observation period, 2-47 months). HAIC was continued in two patients, although anticancer drugs did not distribute to all liver tumors. Arteries once embolized with coils alone spontaneously recanalized at a significantly higher rate than those with NBCA (eight of 192 vs one of 144, P =.048). Rate of heterogeneously poor distribution was significantly higher in those with two or more hepatic arteries than in those with one (seven of 17 vs nine of 111, P =.001). CONCLUSION: TAE for various splanchnic organs is useful for efficient performance of long-term HAIC.     

Optical bioimaging: from living tissue to a single molecule: calcium imaging in blood vessel in situ employing two-photon excitation fluorescence microscopy

Recent developments in optoelectronics permit real-time Ca(2+) imaging of thin planes within cells utilizing laser scanning confocal microscopy (LSCM). However, a major complication associated with this imaging system involves increased phototoxicity with improved spatiotemporal resolution. Two-photon excitation microscopy (TPEM) helps to minimize phototoxicity due to the restriction of this technique to the volume proximal to the geometric focus of the light. In this study, the capability of Ca(2+) imaging was investigated employing recently developed real-time TPEM, RTS2000MP (Bio-Rad, Tokyo) with a mode-locked Ti-sapphire laser. Z-axis resolution of RTS2000MP with high NA objectives defined as full-width at half maximum (FWHM) with a 0.5-microm fluorescent bead provided values nearly identical to those obtained with LSCM at a small pinhole (0.2 mm) (approximately 0.6 microm). When serial sectioning of 21 sequential images at 0.3-microm intervals in cultured endothelial cells loaded with calcein and tetramethyl-rhodamine methylester were performed with TPEM, the z-axis resolution was higher than that observed with LSCM; moreover, the photobleaching rate was significantly lower than that obtained with LSCM. Maximum fluorescence intensities were detected at 780 nm in excitation spectra of fluo-3 and fluo-4 Ca(2+)-sensitive probes with TPEM. Fluorescence images in mouse arterial endothelial cells loaded with fluo-4 could be clearly visualized by TPEM in situ. Application of acetylcholine caused oscillatory increase in [Ca(2+)](i) of endothelial cells; subsequently, relaxation along the major axis of smooth muscle cells was evident. Furthermore, consecutive long-lasting experiments could be repeated with identical response in the same microscopic field. In conclusion, fluorescence imaging employing TPEM is useful for Ca(2+) imaging in blood vessels in situ.     

Interaction of G protein beta subunit with inward rectifier K(+) channel Kir3

G protein betagamma subunits bind and activate G protein-coupled inward rectifier K+ (GIRK) channels. This protein-protein interaction is crucial for slow hyperpolarizations of cardiac myocytes and neurons. The crystal structure of Gbeta shows a seven-bladed propeller with four beta strands in each blade. The Gbeta/Galpha interacting surface contains sites for activating GIRK channels. Furthermore, our recent investigation using chimeras between Gbeta1 and yeast beta (STE4) suggested that the outer strands of blades 1 and 2 of Gbeta1 could be an interaction area between Gbeta1 and GIRK. In this study, we made point mutations on suspected residues on these outer strands and investigated their ability to activate GIRK1/GIRK2 channels. Mutations at Thr-86, Thr-87, and Gly-131, all located on the loops between beta-strands, substantially reduced GIRK channel activation, suggesting that these residues are Gbeta/GIRK interaction sites. These mutations did not affect the expression of Gbeta1 or its ability to stimulate PLCbeta2. These residues are surface-accessible and located outside Gbeta/Galpha interaction sites. These results suggest that the residues on the outer surface of blades 1 and 2 are involved in the interaction of Gbetagamma with GIRK channels. Our study suggests a mechanism by which different effectors use different blades to achieve divergence of signaling. We also observed that substitution of alanine for Trp-332 of Gbeta1 impaired the functional interaction of Gbeta1 with GIRK, in agreement with the data on native neuronal GIRK channels. Trp-332 plays a critical role in the interaction of Gbeta1 with Galpha as well as all effectors so far tested.     

Simple visualization of the corticospinal pathway using tractography: one-ROI and two-ROI methods

Diffusion tensor imaging (DTI), a magnetic resonance (MR) technique to analyze diffusion anisotropy of the brain, is able to demonstrate subtle white matter anatomy. Tractography is expected to be a unique, non-invasive tool to provide more pertinent insights into brain structure and orientation not accessible by conventional MRI. In this report, preliminary experiences of visualization of the corticospinal tract using tractography are described. DTI of the brain was performed in 5 normal volunteers using single-shot echo-planar imaging, then tractography was generated by our original software. We determined that the two-region-of-interest (ROI) method is superior to the one-ROI method.     

Endoscopic local ablation therapy (ELAT) for hepatocellular carcinoma--inventive approaches to achieve radical treatment and to expand the indication of ELAT

We introduce some inventive approaches in endoscopic local ablation therapy (ELAT) for patients with hepatocellular carcinoma (HCC). ELAT is applied in cases of HCC when the tumor is smaller than 3 cm on the surface of the liver (smaller than 4 cm with extrahepatic growth), and tumor numbers < or = 3. Appropriate use of the laparoscopic, thoracoscopic and hand-assisted approaches, suitable preceding embolizations with the angiographic technique, a combination of ablation therapy, and the use of CO2-angio US, DIMON puncture system and cluster needle are important. If necessary, additional surgeries such as endoscopic hepatectomy, laparoscopic cholecystectomy or laparoscopic devascularization must be performed together. As a result, it will be possible to expand the indication of ELAT safely and radically.     

Visualization of pulmonary arteriovenous malformation by three dimensional computed tomography: a case report

Pulmonary arteriovenous malformation (PAVM) is an anomaly condition characterized by abnormal vascular communications between arteries and veins in the lungs. Hereby we describe a 60-year-old female with PAVM. Although the patient was asymptomatic, an abnormal round opacity was found on a chest X-ray film. Computed tomography (CT) of the lung disclosed nodules connected with enlarged vessels. Because PAVM was suspected, the patient was further evaluated by spiral CT coupled with three dimensional reconstruction of the images (3D-CT). As a result, PAVM was clearly visualized and invasive procedures such as angiography was not performed. The present case illustrates that 3D-CT is a diagnostic procedure of choice when PAVM is suspected.     

Distinct methylation pattern and microsatellite instability in sporadic gastric cancer.

Aberrant 5' CpG island methylation is an alternative mechanism of gene inactivation during the development of cancer as demonstrated for several tumor-suppressor genes. Also, marked relationship of microsatellite instability (MSI) and DNA methylation has been reported in sporadic colorectal cancer, which is a result of epigenetic inactivation of hMLH1 in association of promoter hypermethylation. In the present study, we investigated the 5' CpG island hypermethylation of hMLH1, E-cadherin and p16 in 61 primary gastric cancers (GCs) by using combined bisulfite restriction analysis (COBRA) and methylation-specific PCR (MSP), and their MSI status. Of 61 GCs investigated, 5 (8.1%) tumors presented hMLH1 methylation, 16 (26.2%) and 25 (40.9%) showed E-cadherin and p16 methylation respectively, and 8 (13.1%) presented high-frequency MSI (MSI-H). Of the 8 MSI-H patients, 5 presented hMLH1 methylation, whereas no low-frequency MSI (MSI-L) and microsatellite stable (MSS) cases exhibited hMLH1 methylation (5/8 vs. 0/43, p < 0.00001). Furthermore, these patients also presented E-cadherin and p16 hypermethylation. Our data showed a significant correlation between hMLH1 methylation and MSI in GC, and suggested that a common mechanism of aberrant de novo methylation can be postulated in these cancers.     

The effect of drug therapy and stellate ganglion block with or without oxygen inhalation on sudden hearing loss

Forty-one patients suffering from sudden hearing loss were studied by the following method. Twenty patients (group A) were treated with oral administration of prednisolone, intravenous administration of vitamin B and C, furosemide and stellate ganglion block. Another 21 patients (group B) were treated with oral administration of these drugs, stellate ganglion block and oxygen inhalation. Forty six percent of all these patients, 35 percent of group A and 57 percent of group B, regained less than 20 dB of their normal hearing level. The patients who are younger, having shorter duration from first finding of symptoms to starting of therapy and smaller average deficiency of hearing, without dizziness are easy to recover. Oxygen inhalation with drug therapy and stellate ganglion block is a useful treatment for sudden hearing loss.     

Recognition of the polypeptide core of mucin by monoclonal antibody MUSE11 against an adenocarcinoma-associated antigen

Monoclonal antibody (MAb) MUSE11 detects an adenocarcinoma-associated antigen and is useful for the serodiagnosis of pancreas cancer. We established a sandwich enzyme immunoassay using MAb MUSE11 and MAb DF3 against a breast cancer-associated mucin core protein as a catcher and a tracer, respectively. With this assay system, the binding of the tracer MAb DF3 to an antigen in the human kidney tissue lysate was clearly inhibited by MAb MUSE11. In addition, MAb MUSE11 showed a significant binding activity to the synthetic peptide corresponding to the tandem repeat of a human epithelial mucin core protein. These data suggest that MAb MUSE11 could detect the polypeptide core of a mucin, and may be of use for studying mucin as a gene product.