Finite element analysis of the re-entrant type resonant cavity applicator for brain tumor hyperthermia

In this paper, we have proposed a new heating method in which high frequency electric fields in a re-entrant type resonant cavity are used for the heating of deeply seated tumors. In this method, a human head is placed between the gap of the inner re-entrant cylinders, and is heated with electromagnetic fields stimulated in the cavity without contact between the surface of the human head and the applicator. Here, we proposed a new method to control the heating area. In this method, the resonant frequency inside the cavity was changed, then we use the TM010-like mode and the TM012-like mode from various types of the resonant frequency. First, the computer simulation results of electric and magnetic field patterns are presented. Second, a comparison of the heating properties of TM010-like mode and TM012-like mode are discussed. The heating area of the center of agar phantom is more concentrated by using TM012-like mode than that of using TM010-like mode. From these results, it is confirmed that the proposed method can be controlled to heat the various sizes of deep tumors.

Heating properties of re-entrant resonant applicator for brain tumor by electromagnetic heating modes

This paper discusses a new method to control the heating area of a re-entrant resonant cavity applicator for brain tumor hyperthermia treatment non-invasively. We have already discussed about the effectiveness of a developed system with experiments of heating an agar phantom and computer simulations. Here, in order to heat a deep brain tumor, we propose the heating method of using several electromagnetic heating modes which are transverse magnetic (TM) modes. In this method, TM010-like and TM012-like modes obtained by selecting resonant frequencies can be used to heat the deep brain tumors. To control the heating area of the modes the agar phantom is used in the heating experiments by the developed system. From these results, we found that the heating area of the agar phantom by using TM012-like mode is about 50% of the heating area of TM010-like mode. It is found that the proposed heating system can be applicable to the hyperthermia treatment of brain tumors corresponding to the size and the position where it occurred.

Heating properties of re-entrant resonant cavity applicator for brain tumor with simple head model

We have already confirmed the effectiveness of the re-entrant resonant cavity applicator system with non-invasive experiments of heating cylindrical agar phantoms and computer simulations. This paper discusses the heating properties of the developed heating system with a human head model made of agar for brain tumor hyperthermia treatment. First, we present the results of heating a uniform agar head model with the developed heating system. In the experiments, the temperature rise at the center of the agar was about 8 degrees C, it was found that the center of the agar is heated to maximum temperature non-invasively. Second, we present the results of heating a non-uniform agar head model having an oral cavity and a nasal cavity. We found that the center of the agar can be heated to maximum temperature as well as uniform agar head model. From these results, it is confirmed that the possibility of effective hyperthermia for various types of deep-seated brain tumors.

Covered expandable metallic stent placement for hemostasis of colonic bleeding caused by invasion of gallbladder carcinoma

A 72-year-old Japanese man was admitted to our hospital complaining of right upper-quadrant abdominal pain, blood in his stool, and symptoms of anemia. On physical examination a hard mass, about 6 cm in diameter, was palpable in the right upper quadrant of the abdomen. Computed tomography revealed a gallbladder carcinoma which had invaded the transverse colon, with liver metastasis. We diagnosed gallbladder carcinoma, stage IVB. Colonoscopy was performed for persistent blood in the stools. This revealed an elevated lesion which appeared to be an invasion of gallbladder carcinoma, with diffuse bleeding from the right-side of the transverse colon. It proved difficult to stop this bleeding by ordinary therapeutic endoscopy. In order to achieve hemostasis we therefore inserted a covered Ultraflex metallic stent to compress the tumor. After stent placement, blood was no longer seen in the patient's stools, he became able to eat soft food and was discharged. This treatment was uninvasive and effective. Covered stent placement appears to be a new and useful method in the management of bleeding from malignant gastrointestinal tumors.

Start-up of full-scale anaerobic digesters treating municipal solid waste

Raising organic loading rate, and the behavior of dissolved CODcr (D-CODcr), VFA and specific methanogen activity, were investigated through a laboratory experiment for the start-up of a sludge recycling center. Moreover, application for MPN-PCR methods using a gene as a direct technique to measure the quantity of methanogen was attempted. It was recognized that specific methanogen activity depends on the quantity of methanogen, and that gas production does not reflect the condition of methane fermentation. The methane fermentation condition was checked through the specific methanogen activity and analysis of D-CODcr. The target organic loading rate was reached in the short period of about 30 days, and rapid start-up was successfully attained for a full-scale anaerobic digester.

Concise synthesis of ciguatoxin ABC-ring fragments and surface plasmon resonance study of the interaction of their BSA conjugates with monoclonal antibodies

Monoclonal antibodies (mAbs), 4H2 and 6H7, were prepared previously using a protein conjugate of a 1:1 epimeric mixture of the synthetic ABC-ring fragments of ciguatoxin (CTX), 3 and 4. Here, the interactions of these mAbs with the fragments of CTX and CTX3C, 3 and 5, were investigated by surface plasmon resonance (SPR) spectroscopy in an attempt to clarify an antigenic determinant. Compared with the previous synthesis, the fragment 3 possessing the 2S configuration was synthesized from tri-O-acetyl-D-glucal much more effectively. The mAb 4H2 was already known to show a dose-dependent binding to the bovine serum albumin (BSA) conjugate of 3, but not to that of 5. The present SPR study of 4H2 demonstrates that the A-ring side chain of 3 plays a decisive role as an epitope. Therefore, SPR can effectively replace the ELISA method for the analysis of mAbs.

A novel [2 + 2] photodimerization of N-[(E)-3,4-methylenedioxycinnamoyl]dopamine in the solid state

[reaction: see text] To give photoreactivity to catecholamines, N-cinnamoyl-substituted dopamines (E)-5a-5c and O,O'-dimethyldopamines (E)-3a-3c were prepared under solvent-free conditions. A particularly interesting observed photoreactivity was that of N-[(E)-3,4-methylenedioxycinnamoyl]dopamine ((E)-5c), which underwent a novel type of [2 + 2] photodimerization in the solid state, giving exclusively a tricyclic product 8. This reaction is the first example of solid-state photoaddition of an alkene to the benzene ring.

Difference in hepatic tissue oxygenation between total vascular exclusion and inflow occlusion of the liver and the possible role of hepatic venous blood under liver ischemia

The difference between total vascular exclusion (TVE) and inflow occlusion (IO) of the liver was assessed by the extent of DNA injury in rats and by hepatic tissue oxygen saturation (SahtO2) in pigs. Moreover, the role of hepatic venous blood under liver ischemia was discussed. Seventy percent of the rat livers were exposed to complete IO (hepatic artery + portal vein) or to TVE (IO + hepatic vein) for 30 or 60 min. DNA strand breaks following blood flow interception were measured using the in situ nick translation technique as an indicator of liver damage. IO/TVE were performed on pigs as well under portosystemic bypass, and the oxygen saturation of the hepatic venous blood (SahvO2) was altered by changing the fraction of inspiratory oxygen or by oxygenating the inferior caval blood using an extracorporeal membrane oxygenator. The changes in SahtO2 were measured sequentially using near-infrared spectroscopy. The results were as follows: (1) DNA injury occurred more severely under TVE than under IO of the rat liver at the end of ischemia, as well as 30 min after revascularization. (2) SahtO2 during TVE was significantly lower than that during IO. (3) The increase in SahvO2 by oxygenation of the inferior caval blood resulted in the elevation of SahtO2 under IO. In conclusion, TVE could cause greater damage to the liver than IO due to the lack of the hepatic venous blood. Hepatic venous blood might play an important role in hepatic tissue oxygenation in the case of hepatic blood flow interception.

Stimulation of hyaluronan synthesis by tumor necrosis factor-alpha is mediated by the p50/p65 NF-kappa B complex in MRC-5 myofibroblasts

The lesions of fibrocontractive diseases result from an excessive myofibroproliferative response to numerous forms of inflammatory stimuli, which elicit the net deposition of extracellular matrix (ECM) in the interstitium of the affected tissue. Hyaluronan (HA), reported to be a key player supporting cellular migration and adherence, is a major component of ECM that undergoes dynamic regulation during inflammation. The molecular regulation of HA biosynthesis by inflammatory cytokines on myofibroblasts is not yet completely understood. Here we report the biochemical characteristics of the lung myofibroblast cell line MRC-5, and we demonstrate that the production of HA by this cell line is inducible by the proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), at the message level of HA synthase (HAS). In TNF-alpha-stimulated MRC-5 cells, DNA-binding and competition experiments indicated that the predominant NF-kappa B binding activity detected with nuclear extract-stimulated cells is mediated by the p50/p65 complex. Using antisense oligonucleotides, we confirmed that the TNF-alpha-stimulation of HA synthesis by MRC-5 cells is dependent on the activation of the p50/p65 NF-kappa B complex. These findings indicate that TNF-alpha production within inflamed tissues may enhance the HA synthesis via the transcriptional induction of HAS on myofibroblasts, thereby providing a provisional matrix for supporting cellular migration and adhesion, and that the p50/p65 NF-kappa B complex that plays an important role in the regulation of HA production by TNF-alpha might be an appropriate target for therapeutic compounds to treat tissue fibrosis accompanied by inflammation.

Molecular analysis of suppression of interleukin-8 production by rebamipide in Helicobacter pylori-stimulated gastric cancer cell lines

Interleukin-8 (IL-8) may play an important role in Helicobacter pylori infection-associated chronic active gastritis and peptic ulcer disease in human. We have recently reported that a gastric cancer cell line, MKN45, produced a massive amount of IL-8 upon coculture with live H. pylori. Moreover, H. pylori induced the activation of NF-kappaB as well as AP-1, leading to IL-8 gene transcription. In this study, we evaluated the effect of rebamipide, an antigastritis and antiulcer agent, on H. pylori-induced IL-8 production. Rebamipide inhibited the production of IL-8 in several gastric cancer cell lines infected with H. pylori. In addition, rebamipide suppressed H. pylori-induced IL-8 gene expression at the transcriptional level as revealed by northern blotting analysis and luciferase activity in cells that were transfected with a luciferase expression vector linked with a 5'-flanking region of the IL-8 gene (bp -133 to +44). Furthermore, rebamipide significantly suppressed the NF-kappaB activation by H. pylori infection. These results suggest that rebamipide may protect against the mucosal inflammation associated with H. pylori infection through inhibition of a proinflammatory cytokine, IL-8.

Ultraviolet B-induced cell death in four cutaneous cell lines exhibiting different enzymatic antioxidant defences: involvement of apoptosis

Reactive oxygen species (ROS) play a role in the modulation of apoptosis. Antioxidant defence mechanisms against cell death involving apoptosis due to UVB irradiation were studied on three established cell lines (SCC derived from human skin squamous cell carcinoma, F-SV and F-ST derived from human skin fibroblasts) which were susceptible to cell death by UVB irradiation (12.5-250 mJ/cm2), and one cell line (N-F) derived from primary cultured human skin fibroblasts which was resistant to cell death. We compared antioxidant defences between the three established cell lines and N-F, measuring four antioxidant enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and glutathione reductase (GR) and a non-enzymatic antioxidant glutathione. The greatest difference was that Cu, Zn-SOD activity in N-F was 3-4-times the three other cell lines. Though SCC had much larger amounts of glutathione and higher antioxidant enzyme activities except for Cu, Zn-SOD than N-F, SCC was very susceptible to cell death. After UVB irradiation (at 16 h after 12.5 mJ/cm2), in all cell lines, SOD activity increased 1.1-1.3-times that of non-irradiated cells, while other enzyme activities remained constant. This presumably represents a protective response against ROS generated during UVB irradiation. N-F which was resistant to UVB-induced cell death had higher Cu, Zn-SOD activity before UVB irradiation, and a larger increase of SOD (mainly Mn-SOD) after UVB exposure than the other cell lines which were susceptible to cell death. Therefore, we conclude that the most important enzymatic antioxidant to protect cells from UVB damage is SOD.

Antisense sequences of the nbl gene induce apoptosis in the human promyelocytic leukemia cell line HL-60

Apoptosis is induced by the transcriptional inhibitor actinomycin D (Act D) in various cell types, particularly many leukemic cell lines such as HL-60. A common feature of these cell lines is their high constitutive expression level of the nbl gene, which was originally isolated by virtue of its abundance in a Namalwa Burkitt lymphoma cDNA library. In contrast, cell lines which constitutively express nbl at low levels appear not to undergo typical apoptotic death in response to Act D. Apoptotic induction by Act D in cells which normally express nbl at high levels was found in this study to be closely associated with a decline in nbl mRNA levels, raising the possibility that apoptosis could be induced by lowering nbl expression levels in such cells. Transient expression of nbl antisense sequences in HL-60 cells decreased cell viability, and induced typical apoptotic morphology such as cell shrinkage, chromatin condensation and nuclear fragmentation. Incubation with nbl antisense oligomers also induced similar features in HL-60 cells and in another high nb-expressing cell line, Jurkat, but had little effect in HepG2 cells which constitutively express nbl at low levels. These findings suggest that lowering constitutively high levels of nbl expression can induce apoptosis.

Topical application of alpha-tocopherol modulates the antioxidant network and diminishes ultraviolet-induced oxidative damage in murine skin

The aim of this study was to investigate the effects of topical alpha-tocopherol application on epidermal and dermal antioxidants and its ability to prevent ultraviolet (UV)-induced oxidative damage. Hairless mice received topical applications of alpha-tocopherol 24 h before a single, acute UV irradiation (10 x minimal erythemal dose). The four major antioxidant enzymes (catalase, superoxide dismutase, glutathione reductase and glutathione peroxidase), hydrophilic and lipophilic antioxidants, and lipid hydroperoxides, markers of oxidative damage, were assayed in both epidermis and dermis of hairless mice. Topical alpha-tocopherol treatment increased dermal superoxide dismutase activity by 30% (P < 0.01) and protected epidermal glutathione peroxidase and superoxide dismutase from depletion after UV irradiation. Total and reduced glutathione levels in the epidermis increased by 50% after the topical treatment (P < 0.05), as did dermal ascorbate levels (by 40%: P < 0.01). The topical treatment increased alpha-tocopherol levels both in the epidermis (62-fold) and the dermis (22-fold: P < 0.001 in each layer). Furthermore, alpha-tocopherol treatment significantly reduced the formation of epidermal lipid hydroperoxides after UV irradiation (P < 0.05). These results demonstrate that topical administration of alpha-tocopherol protects cutaneous tissues against oxidative damage induced by UV irradiation in vivo, and suggest that the underlying mechanism of this effect involves the up-regulation of a network of enzymatic and non-enzymatic antioxidants.

Calorimetric observation of a GroEL-protein binding reaction with little contribution of hydrophobic interaction

Binding of Escherichia coli chaperonin, GroEL, to substrate proteins with non-native structure, reduced alpha-lactalbumin (rLA) and denatured pepsin, were analyzed by isothermal titration calorimetry at various temperatures in the presence of salt (0.2 M KCl). Both proteins bound to GroEL with 1:1 stoichiometry and micromolar affinity at all temperatures tested. However, thermodynamic properties of their binding to GroEL are remarkably different from each other. While heat capacity changes (DeltaCp) of rLA-GroEL binding showed large negative values, -4.19 kJ mol-1 K-1, that of denatured pepsin-GroEL binding was only -0.2 kJ mol-1 K-1. These values strongly indicate that the hydrophobic interaction is a major force of rLA-GroEL binding but not so for denatured pepsin-GroEL binding. When salt was omitted from the solution, the affinity and DeltaCp of the rLA-GroEL binding reaction were not significantly changed whereas denatured pepsin lost affinity to GroEL. Thus, in the non-native protein-GroEL binding reaction, thermodynamic properties, as well as the effect of salt, differ from protein to protein and hydrophobic interaction may not always be a major driving force.

Mitochondrial trifunctional protein deficiency associated with recurrent myoglobinuria in adolescence

A 23-year-old man with recurrent myoglobinuria had low muscle-free carnitine levels and deficient fasting ketogenesis. Urinary organic acid analysis showed large amounts of C6-C14 3-hydroxydicarboxylic acids. Mitochondrial trifunctional protein (TP), harboring long-chain enoyl-coenzyme A (CoA) hydratase, long-chain 3-hydroxyacyl-CoA dehydrogenase, and long-chain 3-ketoacyl-CoA thiolase showed markedly decreased activity in fibroblasts. On immunoblot analysis, the TP content of his fibroblasts was less than 2% that of the control cells. TP deficiency can be a life-threatening disorder with early infantile onset, but it can also present in adolescence with recurrent myoglobinuria.

A strong association between HLA-B*5101 and Behçet's disease in Greek patients

Behçet's disease is known to be associated with HLA-B51, one of the split antigens of HLA-B5, among many different ethnic groups. In a Greek population, an increased incidence of HLA-B5 in the patient group has also been reported. Because the B51 antigen has been recently identified to comprise seven alleles, B*5101-B*5107, we performed HLA-B51 allele genotyping by the PCR-SSP method as well as serological HLA-A and -B typing among 31 Greek patients with Behçet's disease to investigate whether there is any correlation between one particular B51-associated allele and Behçet's disease. The frequency of B51 was remarkably high (80.6%) in the patient group as compared to the ethnically matched control group (26.7%). In addition, HLA-A26 was also increased in the patients (29.0%) as compared with the healthy controls (3.3%). B51 allele genotyping revealed that all these B51-positive patients carried B*5101. This study revealed a strong association of Behçet's disease in Greeks with one of the B51 subantigens, providing insight into the molecular mechanism underlying an HLA association with Behçet's disease.

Comparison of tracheal aspiration with other tests for diagnosis of Rhodococcus equi pneumonia in foals

The diagnostic value of tracheal aspiration was evaluated through comparison with other diagnostic methods using an experimental model of Rhodococcus equi (R. equi) pneumonia in foals. Pneumonia was induced by spraying of the virulent R. equi strain ATCC 33701 into the trachea of foals. All foals developed fever from 11 to 16 days after bacterial inoculation. One foal was euthanized on day 26 due to its poor prognosis, and other foals euthanized on day 43. During the experiment, some tests for diagnosis of Rhodococcus equi pneumonia such as tracheal aspiration, radiography, serodiagnosis and fecal culture were carried out. R. equi was continually isolated from tracheal aspirates collected via a silicone catheter inserted transnasally on day 8 to day 32 after bacterial inoculation. On the other hand, radiography, serodiagnosis and fecal culture were demonstrated to be valuable diagnostic methods, but to be limited compared with tracheal aspiration. Indirect fluorescent antibody technique (IFA) using a monoclonal antibody against the 15- to 17-kDa virulence-associated antigens (VapA) of R. equi and PCR targeting the structural gene of VapA detected bacteria in tracheal aspirates less sensitively than the isolation technique although they were more rapid. Therefore, we conclude that a combination of tracheal aspiration and bacterial isolation was the most valuable method for routine diagnosis of R. equi pneumonia in foals.

The role of histamine in ethanol-induced gastric mucosal injury in the rat

It has been suggested that changes in the micro circulatory system are related to the early production of acute gastric mucosal injury and inflammatory factors such as prostaglandins, histamine, etc., have been considered as contributing to the development of the injury. We assessed the permeability of the gastric mucosa in rats with ethanol-induced acute mucosal injury by measuring the leakage rate of 51chronium-ethylene-diamine-tetraacetic acid (51Cr-EDTA) into the gastric juice. Histamine concentrations in the gastric mucosa was measured by high performance liquid chromatography. The enterochromaffin-like (ECL) cell counts in the gastric mucosa was performed following histamine staining with an enzyme-labeled antibody, and the histamine released due to degranulation was observed. We also investigated the kinetics of endogenous histamine in the gastric mucosa. Five minutes after the administration of ethanol, an increase in permeability, an increase in histamine concentration, and a decrease in ECL cell count were found in the gastric mucosa. These results suggest that endogenous histamine in the gastric mucosa is closely related to the early development of acute gastric mucosal injury.