A chromosomal duplication that includes the canine microsatellite INRA21 in Labrador Retrievers

INRA21 is one of the canine microsatellites recommended for parentage verification by the International Society for Animal Genetics. In Labrador Retrievers, abnormal peak patterns such as three-peak patterns during capillary electrophoresis were frequently observed at INRA21. Pedigree analysis indicated that the abnormal peak patterns were due to inheritable causes, and semiquantitative multiplex (SQM) PCR analysis showed that the abnormal peak patterns were caused by chromosomal duplication. Walking SQM-PCR analysis revealed that the size of the duplicated segment was approximately 1.58 Mb. Genotypes of microsatellites within the duplicated segment indicated that the duplication was an identical-by-descent mutation. This duplication is probably carried by more than half of the dogs in the Japanese population of Labrador Retrievers. The abnormal peak patterns at INRA21 were also observed in German Shorthaired Pointers and Flat-Coated Retrievers. Genotyping analysis of the microsatellites within the duplicated segment in Labrador Retrievers suggested that the abnormal peak patterns observed in the two breeds were due to the duplication inherited from the same ancestor as the duplication of Labrador Retrievers. This study urges attention to the use of INRA21 and shows an example of copy number polymorphisms that are characteristic to dog breeds or lineages.

Combination chemotherapy of S-1 and low-dose twice-weekly cisplatin for advanced and recurrent gastric cancer in an outpatient setting: a retrospective study

BACKGROUND

We have reported the efficacy and safety of S-1 combined with low-dose consecutive cisplatin therapy for advanced and recurrent gastric cancer, but the regimen was difficult because daily cisplatin administration was necessary. We have already confirmed that cisplatin of 6 mg/m2 twice-weekly maintained the same protein-bound Pt concentration as that of 3 mg/m2 of cisplatin daily. In the present study, the efficacy and safety of a combination of S-1 and low-dose twice-weekly cisplatin were investigated.

PATIENTS AND METHODS

The participants were 32 patients treated at our hospital, and all were admitted for the first 2 weeks of therapy. S-1 at 80 mg/m2 daily was administered orally in two divided doses. Cisplatin at 6 mg/m2 was administered by intravenous drip infusion over 30 minutes on 2 days each week, day 1 and day 4. Each treatment cycle consisted of 4 weeks of drug administration followed by a 2-week drug-free period (6 weeks in total).

RESULTS

A total of 146 cycles were administered, with a median of three cycles (range: 1-24) per patient. The results were rated as a complete response in 1 case, partial response in 24 cases and stable disease in 5 cases. The response rate was 78.1% (25/32) and the median survival time was 12.0 months (95% confidence interval (CI) 8.9-15.1 months). The response rate did not differ between previously treated and untreated patients. The one-year survival rate was 48.2% (95% CI 30.3-66.0%). The major adverse reactions were myelosuppression and gastrointestinal symptoms. The total incidence of grade 3 or greater adverse reactions was 15.6% (5/32).

CONCLUSION

The combination of S-1 and low-dose twice-weekly cisplatin therapy appears to be highly efficacious and safe and shows promise as a useful treatment strategy, even in outpatient clinics.

FK506-protective effects against trimethyltin neurotoxicity in rats: hippocampal expression analyses reveal the involvement of periarterial osteopontin

There is little information on the molecular mechanisms in FK506-mediated neuroprotection. In the present study, we investigated the protective effect of FK506, an immunosuppressant and neuroprotectant, on trimethyltin (TMT)-induced neurotoxicity in the rat hippocampus. Histologically, TMT-induced neuronal damage was partially prevented by FK506 in the hippocampal CA1 region, but not in CA3. FK506 treatment significantly reduced the number of apoptotic cells in CA1, but not in CA3, and also prevented induction of cognitive deficits by TMT. Microarray analysis of the rat hippocampus detected 14 genes with TMT-induced alteration of mRNA expression that was rescued by FK506 treatment. Subsequent quantitative RT-PCR analysis confirmed elevated mRNA levels for four inflammatory genes, glutathione S-transferase, lysozyme, matrix Gla protein, and osteopontin after TMT treatment. Upregulation of these genes was reversed by FK506 treatment at 5 days postgavage. Immunohistochemistry revealed that FK506 reduced osteopontin (OPN) induction by TMT in the periarterial area at 5 days postgavage. Our data suggest that inflammatory gene expression is involved in TMT-induced damage to the hippocampal CA1 region, resulting in apoptosis, and that this process is initiated by periarterial OPN activation, and can be alleviated by FK506.

Acute lung injury following an esophagectomy for esophageal cancer, with special reference to the clinical factors and cytokine levels of peripheral blood and pleural drainage fluid

Acute lung injury (ALI) is one of most serious complications to occur after an esophagectomy for esophageal cancer. However, the pathogenesis of ALI is still unclear. The cytokine levels of pleural drainage fluid as well as peripheral blood were measured in 27 patients who had undergone an extended radical esophagectomy. Both the clinical factors and cytokine levels were compared between 11 patients with (group I) and 16 without ALI (group II). ALI occurred more frequently in patients who underwent colon interposition than in those who received a gastric tube reconstruction (86%vs 25%, P = 0.009). The operation time of group I was significantly longer than that of group II. A logistic regression analysis revealed colon interposition to be an independent factor associated with the ALI (P < 0.05). Postoperative anastomotic leakage and systemic inflammatory response syndrome (SIRS) occurred more frequently in group I than in group II (P < 0.01). Both the serum interleukin-6 (IL-6) and IL-8 levels of group I were significantly higher than those of group II. IL-1beta and tumor necrosis factor-alpha were undetectable in the peripheral blood, whereas they were detectable in the pleural effusion. The IL-1beta of pleural effusion was higher in group I than group II. In conclusion, greater surgical stress, such as a longer operative time, is thus considered to be associated with the first attack of ALI. The adverse events developing in the extra-thoracic site, such as necrosis and local infection around anastomosis may therefore be the second attack. Furthermore, ALI may cause not only SIRS but also other complications such as anastomotic leakage.

Prion removal by nanofiltration under different experimental conditions

Manufacturing processes used in the production of biopharmaceutical or biological products should be evaluated for their ability to remove potential contaminants, including TSE agents. In the present study, we have evaluated scrapie prion protein (PrP Sc) removal in the presence of different starting materials, using virus removal filters of different pore sizes. Following 75 nm filtration, PrP Sc was detected in the filtrate by Western blot (WB) analysis when a "super-sonicated" microsomal fraction derived from hamster adapted scrapie strain 263K (263K MF) was used as the spike material. In contrast, no PrP Sc was detected when an untreated 263K MF was used. By using spike materials prepared in a manner designed to optimize the particle size distribution within the preparation, only 15 nm filtration was shown to remove PrP Sc to below the limits of detection of the WB assays used under all the experimental conditions. However, infectious PrP Sc was recovered following 15 nm filtration under one experimental condition. The results obtained suggest that the nature of the spike preparation is an important factor in evaluating the ability of filters to remove prions, and that procedures designed to minimize the particle size distribution of the prion spike, such as the "super-sonication" or detergent treatments described herein, should be used for the preparation of the spike materials.

Nonlinear and adiabatic control of high-Q photonic crystal nanocavities

This article overviews our recent studies of ultrahigh-Q and ultrasmall photonic-crystal cavities, and their applications to nonlinear optical processing and novel adiabatic control of light. First, we show our latest achievements of ultrahigh-Q photonic-crystal nanocavities, and present extreme slow-light demonstration. Next, we show all-optical bistable switching and memory operations based on enhanced optical nonlinearity in these nanocavities with extremely low power, and discuss their applicability for realizing chip-scale all-optical logic, such as flip-flop. Finally, we introduce adiabatic tuning of high-Q nanocavities, which leads to novel wavelength conversion and another type of optical memories.

Constant blood flow reduction in premotor frontal lobe regions in ALS with dementia - a SPECT study with 3D-SSP

OBJECTIVES - We investigated the regional cerebral blood flow in amyotrophic lateral sclerosis with dementia (ALS-D) patients, using single photon emission computed tomography (SPECT). MATERIALS AND METHODS - The (123)I-IMP SPECT data for 5 ALS-D and 16 ALS patients were analyzed using three-dimensional stereotactic surface projection (3D-SSP). RESULTS - 3D-SSP demonstrated marked prefrontal hypoperfusion in all the five ALS-D cases and significant bilateral prefrontal hypoperfusion in group comparisons. CONCLUSIONS - This study revealed prefrontal hypoperfusion in ALS-D cases to be an obvious abnormality with scientific objectivity.

Reduced cardiac 123I-MIBG uptake reflects cardiac sympathetic dysfunction in Lewy body disease

OBJECTIVE

To examine the relation between the results of cardiac (123)I-meta-iodobenzylguanidine (MIBG) scintigraphy and cardiovascular autonomic function in Lewy body disease (LBD).

METHODS

The subjects were 66 patients with LBD, 44 of whom had Parkinson disease (PD), 10 PD with dementia (PDD), and 12 dementia with Lewy bodies (DLB); 20 age-matched healthy subjects were studied as controls. Cardiovascular autonomic function was evaluated on the basis of cardiac (123)I-MIBG uptake, cardiovascular autonomic response on the Valsalva maneuver (VM), and systolic blood pressure (SBP) response on head-up tilt table (HUT) testing.

RESULTS

Patients with LBD had reduced cardiac (123)I-MIBG uptake, cardiovascular autonomic response on the VM, and SBP response on HUT testing as compared with controls. Cardiac (123)I-MIBG uptake and cardiovascular autonomic function in PDD and DLB were severely impaired as compared with those in PD. Cardiac (123)I-MIBG uptake in LDB was not significantly related to vasomotor sympathetic function, baroreceptor reflex gain, cardiac parasympathetic function, or the changes in SBP on HUT testing. Cardiac (123)I-MIBG uptake was, however, significantly related to the blood pressure overshoot in phase IV of the VM.

CONCLUSION

Cardiac (123)I-meta-iodobenzylguanidine uptake clinically reflects cardiac sympathetic dysfunction in Lewy body disease.

An international parentage and identification panel for the domestic cat (Felis catus)

Seventeen commercial and research laboratories participated in two comparison tests under the auspices of the International Society for Animal Genetics to develop an internationally tested, microsatellite-based parentage and identification panel for the domestic cat (Felis catus). Genetic marker selection was based on the polymorphism information content and allele ranges from seven random-bred populations (n = 261) from the USA, Europe and Brazil and eight breeds (n = 200) from the USA. Nineteen microsatellite markers were included in the comparison test and genotyped across the samples. Based on robustness and efficiency, nine autosomal microsatellite markers were ultimately selected as a single multiplex ‘core’ panel for cat identification and parentage testing. Most markers contained dinucleotide repeats. In addition to the autosomal markers, the panel included two gender-specific markers, amelogenin and zinc-finger XY, which produced genotypes for both the X and Y chromosomes. This international cat parentage and identification panel has a power of exclusion comparable to panels used in other species, ranging from 90.08% to 99.79% across breeds and 99.47% to 99.87% in random-bred cat populations.

Salvage esophagectomy after definitive chemoradiotherapy for esophageal cancer

Salvage esophagectomy is performed for esophageal cancer after definitive chemoradiotherapy. The clinical significance and safety of salvage surgery has not been well established. We reviewed 14 cases of salvage esophagectomy following definitive chemoradiotherapy from 1994 through 2005 and investigated complication rates and outcomes. Seven of 14 cases were completely resected with salvage surgery. Operation time and bleeding were greater in patients who experienced incomplete resection (R1/R2). Anastomosis leakage, pulmonary dysfunction and heart failure were recognized in four, two and one patients, respectively. The postoperative complications were more frequent (71.4%) in patients with incomplete resection (R1/R2) than in patients with complete resection (R0) (28.4%). Two patients with complete resection (R0) showed long-term survival. Salvage esophagectomy may be indicated when the tumor can be resected completely after definitive chemotherapy. However, all cases of T4 cancer cannot be resected completely, resulting in a high risk for complications and poor survival.

Modelling the magnetic signature of neuronal tissue

Neuronal communication in the brain involves electrochemical currents, which produce magnetic fields. Stimulus-evoked brain responses lead to changes in these fields and can be studied using magneto- and electro-encephalography (MEG/EEG). In this paper we model the spatiotemporal distribution of the magnetic field of a physiologically idealized but anatomically realistic neuron to assess the possibility of using magnetic resonance imaging (MRI) for directly mapping the neuronal currents in the human brain. Our results show that the magnetic field several centimeters from the centre of the neuron is well approximated by a dipole source, but the field close to the neuron is not, a finding particularly important for understanding the possible contrast mechanism underlying the use of MRI to detect and locate these currents. We discuss the importance of the spatiotemporal characteristics of the magnetic field in cortical tissue for evaluating and optimizing an experiment based on this mechanism and establish an upper bound for the expected MRI signal change due to stimulus-induced cortical response. Our simulations show that the expected change of the signal magnitude is 1.6% and its phase shift is 1 degrees . An unexpected finding of this work is that the cortical orientation with respect to the external magnetic field has little effect on the predicted MRI contrast. This encouraging result shows that magnetic resonance contrast directly based on the neuronal currents present in the cortex is theoretically a feasible imaging technique. MRI contrast generation based on neuronal currents depends on the dendritic architecture and we obtained high-resolution optical images of cortical tissue to discuss the spatial structure of the magnetic field in grey matter.

Simultaneous observation of superficial cortical and intracerebral microvessels in vivo during reperfusion after transient forebrain ischemia in rats using synchrotron radiation

Using a newly developed angiography system that combines monochromatic synchrotron radiation (MSR) as an X-ray source with a high-definition camera or video system, we observed superficial cortical and intracerebral microvessels simultaneously in vivo during reperfusion after transient forebrain ischemia. Transient brain ischemia was induced by 10-min four-vessel occlusion in rats under general anesthesia. Angiographic images were then sequentially obtained at 3 frames/s. The detector features a 7-microm equivalent pixel size projected onto the input area and a 7 mmx7 mm input field. Changes in the cerebral microvessels were observed before and 1, 5, 10, 15, 20 and 30 min after transient cerebral ischemia using the MSR angiography system. The calibers of the internal carotid artery (ICA), middle cerebral artery (MCA), and striate artery (SA) significantly increased 1 min after reperfusion, while the pial arteriole (PA) caliber significantly decreased (76% of base line). The MCA, PA and SA were significantly dilated 5 and 10 min after reperfusion. Although the caliber of the ICA significantly decreased after 30 min reperfusion compared with the basal value, the calibers of the other three vessels remained larger than the basal values throughout the experiment. Early venous filling was observed at 5 and 10 min after reperfusion. The MSR angiography system is useful for investigating morphological changes in both cortical and central branches of cerebral vessels in rats during reperfusion after cerebral ischemia.

Recent advances in the surgical treatment for esophageal cancer in Japan: An experience of 1000 cases who underwent an esophagectomy at a single institute

15011

Background: Most cases of esophageal cancer are squamous cell carcinoma in Japan and the prognosis of such patients tends to be poor. However, the clinical results after an esophagectomy have recently been reported to improve. Methods: The mortality and morbidity as well as the patients’ prognosis were evaluated in 1000 cases of esophageal cancer who all underwent an esophagectomy in the Department of Surgery and Science (Department of Surgery II), Kyushu University, Japan from 1964 to 2006. The incidence of squamous cell carcinoma was 94 %. The patients were divided into three groups according to the operation period: Group I (n=197), Group II (n=432), and Group III (n=371) underwent an esophagectomy during the periods of ‘64-’80, ’81-’93, and ’93-’06, respectively. The incidences of TNM Stage 0 or I gradually increased (4, 19 and 24 %, respectively), while those of Stage IV decreased (28, 19 and 14 %). Results: The 5-yr overall survival rates (OSR) and cause-specific survival rate (CSR) after an esophagectomy for all 1000 cases were 30 and 37 %, respectively. The 5-yr OSRs of Groups I, II and III were 14, 27 and 46 %, while the 5-yr CSRs were 18, 36, and 52 %, respectively (P<0.01 between each group). When the prognoses were compared for each TNM stage, an improvement in the prognosis was observed at every tumor stage. A multivariate analysis (Cox proportional hazard model) revealed not only the age, depth of invasion, node metastasis, curability (each P<0.001) and extent of a lymphadenectomy (P<0.05) but also the operation period (P<0.001) to be independent prognostic factors. The morbidity rates of Groups I, II and III were 62, 38, and 33 %, and the incidences of pulmonary complications were 42, 13 and 14 %, respectively (P<0.01, Group I vs. II and I vs. III). The 30-day mortality rates were 8.1, 2.1 and 0 %, respectively (P<0.01 between each group). Conclusions: An analysis of a total of 1000 cases with esophageal cancer revealed that an esophagectomy has generally been safely performed without any critical pulmonary complications, while an increasingly favorable prognosis has been achieved due to recent advances in surgical techniques and treatment modalities.

No significant financial relationships to disclose.

Akt-mediated YB-1 phosphorylation induces resistance for chemotherapy of gastric cancer

4554

Background: Y-box-binding protein 1 (YB-1), a member of the DNA-binding protein family which contains a cold-shock domain, has pleiotropic functions in response to stimuli of the AKT/PI3K signal pathway. We have previously described a pathway that involves PTEN/AKT/PI3K, thereby mediating chemoresistance in gastric cancer patients. We studied the Akt-mediated YB-1 phosphorylation and resistance to anti-cancer drugs for the treatment of gastric cancer. Methods: Primary gastric carcinoma tissue and the corresponding normal mucosa were both obtained from 81 gastric cancer patients who underwent surgery in the Department of Surgery II at Kyushu University Hospital from the years 1996 to 2000. YB-1 nuclear expression was investigated by immunostaining while AKT activation was investigated by immunostaining with a phosphorylation-specific antibody. The chemotherapeutic sensibilities of these patients were investigated using an MTT assay. LOH of PTEN was studied using a DNA sequencer with D10S796 and D10S1173 microsatellite markers in the same samples. Results: We found the activated AKT to be associated with an increased resistance to multiple chemotherapeutic agents, including those currently used on gastric cancer patients (5-fluorouracil, adriamycin, mitomycin C, and cis-platinum). The YB-1 nuclear expression was recognized in some patients and they closely correlated with a high expression of phosphorylated AKT. A high level of AKT phosphorylation (activated AKT) correlated closely with the LOH of PTEN (p < 0.0008), and the prognosis of patients who had LOH of PTEN was significantly poor in comparison to the other patients. Conclusions: The results of this study indicate that AKT activation and LOH of PTEN mediated the YB-1 activation, thus suggesting that they play an important role in conferring broad-spectrum chemoresistance in gastric cancer patients. These findings thus support the carrying out of new clinical trials for investigations of combination chemotherapy using conventional drugs with a new generation of signal transduction inhibitors.

No significant financial relationships to disclose.

Phase I/II study of S-1 combined with triweekly irinotecan for advanced or recurrent colorectal cancer

14541

Background: A dose-escalation study of irinotecan (CPT-11) combined with S-1, an oral dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine, was performed to determine the maximum-tolerated dose (MTD), recommended dose (RD), dose-limiting toxicities (DLTs), and objective response rate (RR) in advanced or recurrent colorectal cancer. Methods: The subjects were untreated patients with inoperable advanced or recurrent colorectal cancer aged 20–75 years. S-1 was administered orally at 80 mg m-2 day-1 from day 1 to 14 of a 21-day cycle and CPT-11 was given intravenously on day 1 at an initial dose of 80 mg m-2 day-1, stepping up to 150 mg m-2. The treatment was repeated every 3 weeks, unless disease progression was observed. Results: In the phase I portion, only one of six patients at level 1 (80 mg m-2 of CPT-11) developed DLT, grade 3 diarrhea. No other serious adverse reactions occurred (either hematological or non- hematological), and all patients at levels 2 (100 mg m-2) to 5 (150 mg m-2) could receive therapy safely on an outpatient basis. The final RD was determined to be 150 mg m-2. In the phase II portion, fourteen patients including three patients in the final RD phase I portion were evaluated. The median treatment course was six (range: 2–17). The incidences of severe (grade 3–4) haematological and nonhaematological toxicities were 41.7 and 8.3%, respectively, but all were manageable. The RR was 50% (7 of 14, 95%CI: 23.0–77.0%), and Disease Control Rate (PR + SD) was seen in 71.4%. MST is not reached. Conclusions: Our phase I/II trial showed that S-1 combined with CPT-11 achieved a high response rate and could be given safely on an outpatient basis. These findings suggest that the therapy has potential as first- line treatment for inoperable advanced recurrent colorectal cancer. The updated analysis will be presented at the meeting.

No significant financial relationships to disclose.

Dense fimbrial meshwork enhances Porphyromonas gingivalis adhesiveness: a scanning electron microscopic study

BACKGROUND AND OBJECTIVE

The aim of this study was to determine how the fimbriae of Porphyromonas gingivalis function in plaque formation.

MATERIAL AND METHODS

We used scanning electron microscopy to examine aggregates and hemaggregates of fimbria-rich ATCC33277 (parent) and fimbra-poor OZ6301C (pgmA-knockout, mutant) strains of P. gingivalis. We also assessed the hemagglutination activity of the two strains as an indicator of P. gingivalis adhesiveness.

RESULTS

Aggregates of P. gingivalis were composed of bacterial chains and clusters. Rich fimbriae projecting from cells of the parent strain tended to bunch and form a dense meshwork among bacterial cells. In contrast, cells of the mutant strain projected fewer fimbriae and the meshwork was looser. Hemaggregates including cells of the parent strain contained a detached, dense fimbrial meshwork that adhered to erythrocytes. Hemaggregates comprising cells of the mutant strain included bacterial chains and clusters that adhered to erythrocytes by shorter fimbriae than those of the parent strain. The hemagglutination titer of the parent strain was 10-fold higher than that of the mutant strain, although the number of fimbriae per cell of the parent strain was only double that of the mutant strain.

CONCLUSION

The results indicate that P. gingivalis adhesiveness is prominently enhanced by the dense fimbrial meshwork. Thus, the virulence of P. gingivalis is increased by the presence of rich fimbriae.

Estimation of soft X-ray and EUV transition radiation power emitted from the MIRRORCLE-type tabletop synchrotron

The tabletop synchrotron light sources MIRRORCLE-6X and MIRRORCLE-20SX, operating at electron energies E(el) = 6 MeV and E(el) = 20 MeV, respectively, can emit powerful transition radiation (TR) in the extreme ultraviolet (EUV) and the soft X-ray regions. To clarify the applicability of these soft X-ray and EUV sources, the total TR power has been determined. A TR experiment was performed using a 385 nm-thick Al foil target in MIRRORCLE-6X. The angular distribution of the emitted power was measured using a detector assembly based on an NE102 scintillator, an optical bundle and a photomultiplier. The maximal measured total TR power for MIRRORCLE-6X is P(max) approximately equal 2.95 mW at full power operation. Introduction of an analytical expression for the lifetime of the electron beam allows calculation of the emitted TR power by a tabletop synchrotron light source. Using the above measurement result, and the theoretically determined ratio between the TR power for MIRRORCLE-6X and MIRRORCLE-20SX, the total TR power for MIRRORCLE-20SX can be obtained. The one-foil TR target thickness is optimized for the 20 MeV electron energy. P(max) approximately equal 810 mW for MIRRORCLE-20SX is obtained with a single foil of 240 nm-thick Be target. The emitted bremsstrahlung is negligible with respect to the emitted TR for optimized TR targets. From a theoretically known TR spectrum it is concluded that MIRRORCLE-20SX can emit 150 mW of photons with E > 500 eV, which makes it applicable as a source for performing X-ray lithography. The average wavelength, \overline\lambda = 13.6 nm, of the TR emission of MIRRORCLE-20SX, with a 200 nm Al target, could provide of the order of 1 W EUV.

Multiple inhibitory pathways for lipopolysaccharide- and pro-inflammatory cytokine-induced nitric oxide production in cultured astrocytes

We previously showed that lipopolysaccharide (LPS) and pro-inflammatory cytokines utilized different mechanisms for the production of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) in cultured rat astrocytes. To further characterize these regulatory pathways, we tested the effects of inhibitory factors (anti-inflammatory cytokines, cellular cAMP, and glucocorticoid) on aspects of iNOS expression (from transcription to enzyme activity) during LPS- and cytokine-induced astrocyte NO production. Anti-inflammatory cytokines (transforming growth factor-beta and interleukin-4) suppressed both LPS- and cytokine-induced NO production by reducing iNOS protein expression without affecting mRNA levels. Increased cellular cAMP levels, induced by noradrenaline or forskolin, suppressed LPS-induced, but not cytokine-induced, NO production without affecting iNOS protein expression. The glucocorticoid analog, dexamethasone, suppressed LPS-induced, but not cytokine-induced, NO production by reducing iNOS promoter activity. These different mechanisms would allow the fine control of NO concentration in the brain, as well as accounting for the multiple roles of NO in brain physiology and pathology. Moreover, these mechanisms provide useful therapeutic targets for the treatment of neurodegenerative diseases.

Differential cross section and photon-beam asymmetry for the gamma n --> K+ Sigma- reaction at E gamma = 1.5-2.4 GeV

Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations.

K+-independent initiation of motility in chum salmon sperm treated with an organic alcohol, glycerol

Sperm of salmonid fishes are quiescent in the presence of millimolar concentrations of extracellular K+, but motility initiation occurs when sperm are suspended in K+-free medium. In this study, glycerol (CH2OHCHOHCH2OH) treatment of intact sperm in the presence of K+ induced the initiation of motility even though a large amount of K+ was present. Another organic alcohol, erythritol (CH2OH(CHOH)2CH2OH), had a similar effect, but ethylene glycol (CH2OHCH2OH) did not initiate sperm motility. Furthermore, this glycerol-treated sperm showed motility without subsequent addition of ATP and cAMP. CCCP, an uncoupler of the mitochondrial electron-transport chain involved in ATP synthesis, suppressed motility of glycerol-treated sperm, suggesting that ATP synthesis is required for dynein to slide microtubules in glycerol-treated sperm. The amount of intracellular cAMP ([cAMP]i) in glycerol-treated sperm did not increase on motility activation, but a protein kinase A (PKA) inhibitor, H-89, inhibited glycerol-treated sperm motility. In addition, phosphorylation of protein associated with motility initiation also occurred in glycerol-treated sperm, suggesting that the glycerol treatment induces activation of PKA without an increase in [cAMP]i. Taken together, it can be concluded that organic alcohol, glycerol and erythritol induce phosphorylation for motility initiation, bypassing the increase in [cAMP]i as a result of a decrease in extracellular K+ concentration.

Theory and characteristics of transition radiation emitted by low-energy storage-ring synchrotrons for use in X-ray lithography

Existing theory is developed further for description of transition radiation (TR) emitted by low-energy storage-ring synchrotrons. It takes into account the fact that the dielectric constant of the TR target material is a complex function, introduces an expression for the number of passes of an injected electron through the target, and accounts more precisely for the absorption of TR. It is shown that the consideration of the complexity of the dielectric constant results in notable changes of the TR spectrum for emitted photons with energies close to the ionization energies of the target material. Since such TR is used mostly for performing X-ray lithography (XRL), the sensitivity of the photoresist used in XRL is formulated. Maximization of this resist sensitivity can be used for designing optimum targets for XRL. Study of the transmission of TR through a commonly used XRL mask, and its partial absorption in a common photoresist, illustrates that TR emission with E = [490, 1860] eV is most useful for performing such XRL, while E approximately equal to 1 keV is best. It is shown that, for a particular target material, a target consisting of only one foil emits the most TR energy. Optimization of an Al target, based on maximization of the resist sensitivity, indicates that a target containing one Al foil with a thickness of about 200 nm would be best for performing XRL by our low-energy storage-ring synchrotron MIRRORCLE-20SX.

Association of connexin36 and zonula occludens-1 with zonula occludens-2 and the transcription factor zonula occludens-1-associated nucleic acid-binding protein at neuronal gap junctions in rodent retina

Most gap junctions between neurons in mammalian retina contain abundant connexin36, often in association with the scaffolding protein zonula occludens-1. We now investigate co-association of connexin36, zonula occludens-1, zonula occludens-2 and Y-box transcription factor 3 (zonula occludens-1-associated nucleic acid-binding protein) in mouse and rat retina. By immunoblotting, zonula occludens-1-associated nucleic acid-binding protein and zonula occludens-2 were both detected in retina, and zonula occludens-2 in retina was found to co-immunoprecipitate with connexin36. By immunofluorescence, the four proteins appeared as puncta distributed in the plexiform layers. In the inner plexiform layer, most connexin36-puncta were co-localized with zonula occludens-1, and many were co-localized with zonula occludens-1-associated nucleic acid-binding protein. Moreover, zonula occludens-1-associated nucleic acid-binding protein was often co-localized with zonula occludens-1. Nearly all zonula occludens-2-puncta were positive for connexin36, zonula occludens-1 and zonula occludens-1-associated nucleic acid-binding protein. In the outer plexiform layer, connexin36 was also often co-localized with zonula occludens-1-associated nucleic acid-binding protein. In connexin36 knockout mice, labeling of zonula occludens-1 was slightly reduced in the inner plexiform layer, zonula occludens-1-associated nucleic acid-binding protein was decreased in the outer plexiform layer, and both zonula occludens-1-associated nucleic acid-binding protein and zonula occludens-2 were markedly decreased in the inner sublamina of the inner plexiform layer, whereas zonula occludens-1, zonula occludens-2 and zonula occludens-1-associated nucleic acid-binding protein puncta persisted and remained co-localized in the outer sublamina of the inner plexiform layer. By freeze-fracture replica immunogold labeling, connexin36 was found to be co-localized with zonula occludens-2 within individual neuronal gap junctions. In addition, zonula occludens-1-associated nucleic acid-binding protein was abundant in a portion of ultrastructurally-defined gap junctions throughout the inner plexiform layer, and some of these junctions contained both connexin36 and zonula occludens-1-associated nucleic acid-binding protein. These distinct patterns of connexin36 association with zonula occludens-1, zonula occludens-2 and zonula occludens-1-associated nucleic acid-binding protein in different sublaminae of retina, and differential responses of these proteins to connexin36 gene deletion suggest differential regulatory and scaffolding roles of these gap junction accessory proteins. Further, the persistence of a subpopulation of zonula occludens-1/zonula occludens-2/zonula occludens-1-associated nucleic acid-binding protein co-localized puncta in the outer part of the inner plexiform layer of connexin36 knockout mice suggests close association of these proteins with other structures in retina, possibly including gap junctions composed of an as-yet-unidentified connexin.

Phase II clinical trials of combination S-1 plus low-dose twice weekly cisplatin for advanced or recurrent gastric cancer

14013

Background: We reported the efficacy and safety of combined S-1 + low-dose consecutive cisplatin therapy for advanced or recurrent gastric cancer (Clin Cancer Res. 10:1664–9, 2004). However, this procedure was complicated because the daily dosage of CDDP was necessary. We confirmed that 6 mg/m2 dosage of twice weekly Cisplatin were maintained equal protein binding Pt concentration after daily treatment of 3 mg/m2 dosage of Cisplatin. We examined an effect and safety of a Combination S-1 plus low-dose twice weekly Cisplatin treatment. Methods: All the subjects were admitted to the hospital as inpatients for the first 2 weeks of therapy. S-1 was administered orally daily at the daily dose level of 80 mg/m2 (administered in two divided doses). Cisplatin 6 mg/m2 was administered by intravenous drip infusion over 30 minutes on 2days of the week (Day1 and Day4). Each treatment cycle consisted of 4 weeks of drug administration followed by a 2-week drug-free period (6 weeks in total). Results: 32 patients were enroled in this study. The response was rated as complete response in 1 case, partial response in 24 cases and stable disease in 5 cases. The response rate was 78.1% (25/32). The median survival time was 10.3 months. The response rate did not differ between previously untreated patients and patients who had received prior treatment. The major adverse reactions to the therapy were bone marrow suppression and gastrointestinal symptoms. The total incidence of grade 3 or more severe adverse reactions was 15.6% (5/32). Conclusion: Combination S-1 + low-dose twice weekly Cisplatin therapy thus appears to be highly efficacious and safe, offers promise as a useful treatment strategy even at outpatient clinics. [Table: see text]

No significant financial relationships to disclose.

Impact of PTEN/AKT/PI3K signal pathway on the chemotherapy for gastric cancer

4034

Background: Growth factor receptor-mediated signal transduction has been recently implicated in conferring resistance to conventional chemotherapy on cancer cells. We have described a pathway that involves AKT/PI3K to mediate chemoresistance in gastric cancer patients. The phosphatase activity of PTEN is crucial in controlling the phosphatidylinositol-3 (PI-3) kinase signal transduction pathway and in the activation of the protein kinase B(PKB/Akt) proto-oncogene. This indicates that PTEN exerts its tumor-suppressor function by negatively regulating the anitapoptotic PI3-kinase/AKT signaling pathway. Methods: Primary gastric carcinoma tissues and corresponding normal mucosa were obtained from 119 gastric cancer patients who underwent surgery in the Department of Surgery II in Kyushu University Hospital from the years 1996 to 2000. Methylation of PTEN was studied with methylation-specific PCR and LOH (loss of heterozygosity) of PTEN was studied using a DNA sequencer with D10S796 and D10S1173 microsatellite marker in the same samples. AKT activation was investigated by immunostaining with a phosphorylation-specific antibody. The chemotherapeutic sensibilities of these patients were investigated using an MTT assay. Results: We found that methylation of PTEN was rarely recognized, However, the gastric cancer patients who had a higher AKT phosphorylation (activated AKT) appeared to have LOH of PTEN (p < 0.0008), and the prognosis of the patient who has LOH of PTEN was significantly poor. When the chemotherapeutic sensibilities of these patients were studied in an MTT assay, it was found that the activated AKT was associated with increased resistance to multiple chemotherapeutic agents, which included those currently used on gastric cancer patients (5-fluorouracil, adriamycin, mitomycin C, and cis-platinum). Conclusions: The results of this study indicate that AKT activation and LOH of PTEN plays an important role in conferring a broad-spectrum chemoresistance in gastric cancer patients. It also indicates that clinical trials for an appropriate chemotherapy combination with conventional drugs and a new generation of signal transduction inhibitors that inhibit the PTEN/AKT pathway should be considered in treating gastric cancer in the near future.

No significant financial relationships to disclose.

Clinical effects of esophagectomy for patients 80 years of age and older with thoracic esophageal cancer

4049

Background: Esophageal cancer tends to mainly occur in elderly patients. Although a radical operation is the most effective existing therapy, the associated operative morbidity is still high. As a result, the indications for an esophagectomy in elderly patients (especially for patients over 80 years of age) remain controversial. Methods: A total of 599 patients with thoracic esophageal cancer who underwent an esophagectomy by the transthoracic approach since 1986 were evaluated. They were divided into 3 groups depending on age, namely groups I (<69 y.o., n = 441), II (70–79 y.o., n = 143) and III (≥80 y.o., n = 15). No significant differences were observed in the location of the tumor, histological type or stage. A distal esophagectomy with a left thoracotomy was performed for 40, 46, and 47% of the patients, respectively, while the others underwent a subtotal esophagectomy with a right thoracotomy. In group III, surgery was only done for cases with PS 0 or 1 as well as a normal cardiac and pulmonary function (ejection fraction ≥65 %, vital capacity ≥80 %, FEV 1.0% > 70%). Results: Postoperative complications occurred in 31 % of group I and 39 % of group II patients, and the incidence of pulmonary complication was 9 and 18 %, respectively (P < 0.01). In group III, the operative morbidity and mortality were 27 and 0 %, respectively, and pulmonary complications only occurred in one patient (7%). No significant difference was observed in the disease-free survival (DFS: 50, 46 and 58 % for 3yrs, 44, 40 and 33 % for 5 yrs), while the overall survival rates were worse in the older groups as a result of death due to causes other than recurrence (45, 34 and 34 % for 3yrs and 38, 26 and 9 % for 5 yrs in groups I, II and III, respectively. P < 0.01 group I v.s. II). Conclusions: An esophagectomy is considered to be a viable treatment alternative in patients over 80 years of age without increasing morbidity, when the indications for surgery are strictly determined. Furthermore, the DFS in these patients was similar to that observed in younger patients although the incidence of death due to causes other than cancer was found to be higher. An esophagectomy should therefore be considered as an effective treatment strategy even in elderly patients over 80 years of age.

No significant financial relationships to disclose.

Phase II study of S-1 and biweekly docetaxel combination in advanced or recurrent gastric cancer

14031

Background: Docetaxel (TXT) and S-1 are active agents against gastric cancer. A synergistic antitumor effect has been shown in a preclinical study (Takahashi et al., Oncology 2005), and our previous phase I trial demonstrated the safety and tolerability of the combination, and its potent activity. To prospectively evaluate toxicity and efficacy of S-1/ biweekly TXT, we conducted the current phase II study in patients with advanced and recurrent gastric cancer. Methods: Patients (pts) with advanced or recurrent gastric cancer, who have not received any chemotherapy except postoperative chemotherapy (not including S-1 or TXT), were eligible for the trial, and were treated with docetaxel 35 mg/m2 one hour iv infusion on day 1 and 15, and S-1 at a full dose of 80 mg/m2/day for two weeks every four weeks. Results: Thirty-five pts with measurable lesions (RECIST) (10 females, 25 males; performance status [PS] 0/1/2: 23/8/4, age 27–74, differentiated/undifferentiated adenocarcinoma: 19/16) have been enrolled. A total of 113 cycles were administered (median 3, range 1–6), and all pts were assessable for toxicity and efficacy. Grade 3–4 toxicities were: neutropenia in 20.0% (grade 4: 11.4%) of patients, leukocytopenia in 11.4% (grade 4: 0%), anemia in 5.7%, appetite loss in 8.6%, stomatitis in 8.6%, fever in 2.9%, and fatigue in 2.9%. All treatment related toxicities resolved, and no toxic death was reported. Thirteen partial responses (PR) were obtained, resulting in an overall response (OR) rate of 37.1% (95% CI: 0.22–0.55). Thirteen pts (37.5%) had stable disease, and 4 pts (12.5%) progressed. The tumor control rate was 74.3% (95% CI: 0.57–0.88). The median survival time (MST) and time to treatment failure (TTF) were 326 and 75 days, respectively. Conclusions: The combination of S-1/ biweekly TXT is active in advanced or recurrent gastric cancer, and can be given safely with proper management of adverse events even in outpatient clinic. S-1/ biweekly TXT is one of the most effective regimen to control metastatic gastric cancer with less toxicity.

No significant financial relationships to disclose.

Luminescent yeast cells entrapped in hydrogels for estrogenic endocrine disrupting chemical biodetection

In the construction of luminescent yeast cell based fibre-optic biosensors, we demonstrate a novel approach for estrogenic endocrine disrupting chemical (EDC) biodetection by entrapping genetically modified Saccharomyces cerevisiae cells, containing the estrogen receptor alpha-mediated expression of the luc reporter gene, in hydrogel matrices based on calcium alginate or PVA. In order to insure a significant signal, an optimal immobilization ratio of 1:2 alginate 3% (w/v): 5 x 10(6) [cells/ml], respectively, was used with the highest 17-beta-estradiol (beta-E2) induction factor after 2.5 h of incubation with 10[nM] beta-E2. It was shown that biocompatible alginate beads, 4.27-4.55 x 10(5) [CFU/bead], which were characterized by a detection limit of 0.08[microg l(-1)] and an EC50 of 0.64[microg l(-1)] for beta-E2, retained their viability for luminescence measurements after 1 month of storage at -80 degrees C slow freeze condition, and thus repeated cell cultivations were not required. The assay reproducibility for each tested EDC, represented by the coefficients of variation (CV), ranged from 4.35 to 18.47%. An alternative immobilization method, based on a room temperature partial drying of polyvinyl alcohol (PVA) solution (LentiKat Liquid) and cell suspension mix, was investigated with only a slightly lower detection limit for beta-E2 than that reported with alginate beads. Alginate yeast based hydrogels may also be applicable to the analysis of environmental water samples since the trend of detected estrogenic activities with alginate beads roughly correlated with LC-MS-MS analytical results.

Mutations within the tyrosine kinase domain of EGFR gene specifically occur in lung adenocarcinoma patients with a low exposure of tobacco smoking

Somatically acquired mutations in the epidermal growth factor receptor (EGFR) gene in lung cancer are associated with significant clinical responses to gefitinib, a tyrosine kinase inhibitor that targets EGFR. We screened the EGFR in 469 resected tumours of patients with lung cancer, which included 322 adenocarcinomas, 102 squamous cell carcinomas, 27 large cell carcinomas, 13 small cell carcinomas, and five other cell types. PCR with a specific condition was performed to identify any deletion in exon 19, while mutant-allele-specific amplification was performed to identify a mutation in codon 858 of exon 21. EGFR mutations were found in 136 cases (42.2%) with adenocarcinoma, in one case with large cell carcinoma, and in one case with pleomorphic carcinoma. An in-frame deletion in exon 19 was found in 62 cases while an L858R mutation was found in 77 cases. In the 322 cases with adenocarcinoma, these mutations were more frequently found in women than in men (P=0.0004), in well differentiated tumours than in poorly differentiated tumours (P=0.0014), and in patients who were never smokers than in patients who were current/former smokers (P<0.0001). The mutation was more frequently observed in patients who smoked ⩽20 pack-year, and in patients who quit at least 20 years before the date of diagnosis for lung cancer. The K-ras mutations were more frequently found in smokers than in never smokers, and in high-dose smokers than in low-dose smokers. In conclusion, the mutations within the tyrosine kinase domain of EGFR were found to specifically occur in lung adenocarcinoma patients with a low exposure of tobacco smoking.

Comparison of MR images and histochemical localization of intra-arterially administered microglia surrounding beta-amyloid deposits in the rat brain

The therapeutic use of microglial cells has recently received some attention for the treatment of Alzheimer disease (AD), but few non-invasive techniques exist for monitoring the cells after administration. Here we present a magnetic resonance imaging (MRI) technique for tracking microglia injected intra-arterially in vivo. We micro-injected Abeta42 into the left hippocampus and saline into the right hippocampus of rats. We then administered microglia, which were labeled with enhanced green fluorescent protein (EGFP) gene and Resovist, into the carotid artery. After monitoring exogenously administered microglia using MRI, we compared the MR images and the histochemical localization of administered microglia. MRI revealed clear signal changes attributable to Resovist-containing microglia in Abeta-injected areas. Histochemistry demonstrated that EGFP-positive microglia accumulated around Abeta deposits and internalized the peptide. This study demonstrates the usefulness of MRI for non-invasive monitoring of exogenous microglia, and suggests a promising future for microglia/macrophages as therapeutic tools for AD.

Comparison Between Intraperitoneal CO2 Insufflation and Abdominal Wall Lift on QT Dispersion and Rate-corrected QT Dispersion During Laparoscopic Cholecystectomy

This study compared the effect of intraperitoneal CO2 insufflation with abdominal wall lift on RR interval, QT interval, the rate-corrected QT (QTc) interval, QT dispersion (QTD), and the rate-corrected QTD (QTcD) using computerized measurement during laparoscopic cholecystectomy. Thirty patients scheduled for laparoscopic cholecystectomy were randomly assigned to 2 groups: intraperitoneal CO2 insufflation (CO2 group) or abdominal wall lift (lift group). A 12-lead electrocardiogram was monitored to measure parameters. The RR interval, QT interval, and QTc interval did not change significantly during the study in both groups. The QTD and QTcD in the CO2 group increased significantly during CO2 insufflation, and were significantly higher than those of the lift group. Statistically significant increases of QTD and QTcD, which are associated with an increased risk of arrhythmias and cardiac events, occur during CO2 insufflation, and QTD and QTcD in the CO2 group were significantly higher than those of the lift group.

Cardiovascular dysautonomia in Parkinson's disease and multiple system atrophy

OBJECTIVES

To determine whether Parkinson's disease (PD) can be distinguished from multiple system atrophy (MSA) on the basis of the assessment of iodine-123 meta-iodobenzylguanidine (123I-MIBG) radioactivity in heart and cardiovascular autonomic function.

PATIENTS AND METHODS

Seventeen patients with MSA, 39 with PD, and 25 healthy volunteers underwent 123I-MIBG scintigraphy and hemodynamic autonomic function tests using Valsalva maneuver (VM). Baroreceptor reflex sensitivity (BRS) was measured using the slope of the relation between RR interval and blood pressure during the fourth phase.

RESULTS

123I-MIBG radioactivity in heart of patients with PD was lower than that of control subjects and patients with MSA, but there was some overlap between PD and MSA. BRS in patients with PD who had a 123I-MIBG radioactivity similar to that in MSA was larger than that in patients with MSA, with no overlap in any patient.

CONCLUSION

Assessment of BRS may be useful for differentiating between MSA and PD that had a 123I-MIBG radioactivity similar to MSA.

Total cavopulmonary connection: open anastomosis of an extracardiac conduit with vacuum-assisted venous drainage

Insertion of a tube conduit for total cavopulmonary connection is sometimes technically demanding due to the crumpled stump of the inferior vena cava caused by a tourniquet of the inferior vena cava near the division line. Herein we describe an alternative in which the anastomosis is completed during removal of the tourniquet with the application of vacuum-assisted venous drainage. This new technique may alleviate, if not completely eliminate, a concern associated with total cavopulmonary connection with extracardiac conduit in small patients.

A locus on chromosome 9p confers susceptibility to ALS and frontotemporal dementia

OBJECTIVE

To perform genetic linkage analysis in a family affected with ALS and frontotemporal dementia (FTD).

METHODS

The authors performed a genome-wide linkage analysis of a four-generation, 50-member Scandinavian family in which five individuals were diagnosed with ALS and nine with FTD. Linkage calculations assuming autosomal dominant inheritance of a single neurodegenerative disease manifesting as either ALS or FTD with age-dependent penetrance were performed. Further analyses for ALS alone and FTD alone were performed. A parametric logarithm of odds (lod) score of 2.0 or greater was required for further study of a potential locus and crossover (haplotype) analysis.

RESULTS

A new ALS-FTD locus was identified between markers D9s1870 and D9s1791 on human chromosome 9p21.3-p13.3. A maximum multipoint lod score of 3.00 was obtained between markers D9s1121 and D9s2154. Crossover analysis indicates this region covers approximately 21.8 cM, or 14Mb.

CONCLUSIONS

A locus on chromosome 9p21.3-p13.3 is linked to ALS-FTD.

An Ecological Study on the Association of Public Dental Health Activities and Sociodemographic Characteristics with Caries Prevalence in Japanese 3-Year-Old Children

The aim of this ecological study was to determine the association of the frequency of dental health activities conducted as public health service and sociodemographic characteristics with caries prevalence in Japanese 3-year-old children using data for each municipality as one unit. Data on caries prevalence in 3-year-old children in 2000 were obtained from 3,251 municipalities (almost all municipalities in Japan). Caries prevalence for each municipality was recalculated using the empirical Bayes estimation model to make adjustments for variations in municipalities with small numbers of children. Explanatory factors included annual frequency of dental health activities such as dental health education and topical fluoride application programs and various sociodemographic characteristics. Multiple linear regression analysis was applied to examine the associations between caries prevalence and annual frequency of dental health activities with adjustment of other sociodemographic variables. Variations in caries prevalence in municipalities with small populations became smaller after being adjusted by the empirical Bayes estimation model. Multiple linear regression analysis showed significant associations of caries prevalence with sociodemographic characteristics such as the proportion of residents with university degrees, total fertility rate, and the proportion of workers in the manufacturing industry (p < 0.001). Annual frequency of topical fluoride application showed a significant but relatively weak association with caries prevalence (p < 0.001), explaining only 0.8% of the total variation in caries prevalence, whereas no correlation was found between caries prevalence and annual frequency of dental health education. It was concluded that the effect of the fluoride application service on caries prevalence in 3-year-old children, although statistically significant, was of far lower clinical significance than sociodemographic characteristics.

Use of the exogenous Drosophila octopamine receptor gene to study Gq-coupled receptor-mediated responses in mammalian neurons

Diverse excitatory and inhibitory neuronal responses are mediated via Gq-coupled receptors, but the lack of a systematic comparison of different receptors or neurons has hindered a better understanding of these responses. Such a comparison may be provided by an exogenous receptor that is activated by compounds that have no effect on endogenous receptors. We therefore expressed an invertebrate biogenic amine receptor, the Drosophila octopamine receptor, in rat cortical neurons and compared octopamine receptor-mediated responses with those mediated by the group I metabotropic glutamate receptor, the endogenous Gq-coupled receptor in rat cortical neurons. Stimulation of either receptor did not result in a calcium response in octopamine receptor-expressing neurons, although octopamine preferentially elicited a calcium increase in octopamine receptor-expressing PC12h cells, while enhancing the neuronal depolarization-induced calcium increase and the electrical excitability. The increased excitability was caused by inward currents resulting from a reduction in the leak current, which was voltage-independent and blocked by genistein, a non-selective tyrosine kinase inhibitor. These results show that, in cortical neurons, exogenous octopamine receptor in mushroom bodies activated the same cell signaling pathway as endogenous metabotropic glutamate receptor, suggesting that the diverse neuronal responses mediated by Gq-coupled receptors are due to the properties of different neurons, rather than to the properties of the receptors.