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.

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.

An additional simple denitrification bioreactor using packed gel envelopes applicable to industrial wastewater treatment

A simple denitrification bioreactor for nitrate-containing wastewater without organic compounds was developed. This bioreactor consisted of packed gel envelopes in a single tank. Each envelope comprised two plates of gels containing Paracoccus denitrificans cells with an internal space between the plates. As an electron donor for denitrification, ethanol was injected into the internal space and not directly into the wastewater. P. denitrificans cells in the gel reduced nitrate to nitrogen gas by using the injected ethanol. Nitrate-containing desulfurization wastewater derived from a coal-fired thermal power plant was continuously treated with 20 packed gel envelopes (size, 1,000 x 900 x 12 mm; surface area, 1.44 m(2)) in a reactor tank (volume 1.5 m(3)). When the total nitrogen concentration in the inflow was around 150 mg-N x L(-1), the envelopes removed approximately 60-80% of the total nitrogen, and the maximum nitrogen removal rate was 5.0 g-N x day(-1) per square meter of the gel surface. This value corresponded to the volumetric nitrogen removal performance of 0.109 kg-N x m(-3) x day(-1). In each envelope, a high utilization efficiency of the electron donor was attained, although more than the double amount of the electron donor was empirically injected in the present activated sludge system to achieve denitrification when compared with the theoretical value. The bioreactor using the envelopes would be extremely effective as an additional denitrification system because these envelopes can be easily installed in the vacant spaces of preinstalled water treatment systems, without requiring additional facilities for removing surplus ethanol and sludge.

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.

DISC1–NDEL1/NUDEL protein interaction, an essential component for neurite outgrowth, is modulated by genetic variations of DISC1

Disrupted-In-Schizophrenia-1 (DISC1) is a unique susceptibility gene for major mental conditions, because of the segregation of its genetic variant with hereditary psychosis in a Scottish pedigree. Genetic association studies reproducibly suggest involvement of DISC1 in both schizophrenia and bipolar disorder in several ethnic groups. The DISC1 protein is multifunctional, and a pool of DISC1 in the dynein motor complex is required for neurite outgrowth in PC12 cells as well as proper neuronal migration and dendritic arborization in the developing cerebral cortex in vivo. Here, we show that a specific interaction between DISC1 and nuclear distribution element-like (NDEL1/NUDEL) is required for neurite outgrowth in differentiating PC12 cells. Among several components of the dynein motor complex, DISC1 and NDEL1 are selectively upregulated during neurite outgrowth upon differentiation in PC12 cells. The NDEL1 binding site of DISC1 was narrowed down to a small portion of exon 13, corresponding to amino acids 802-835 of DISC1. We demonstrate that genetic variants of DISC1, proximal to the NDEL1 binding site, affect the interaction between DISC1 and NDEL1.

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.

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.

Polymerase Chain Reaction-Based Analysis Using Deaminated DNA of Dodecamer Expansions in CSTB, Associated with Unverricht-Lundborg Myoclonus Epilepsy

Progressive myoclonus epilepsy of the Unverricht-Lundborg type is an autosomal recessive disorder that is characterized clinically by myoclonic seizures and ataxia. The majority of affected individuals carry repeat expansions of a dodecamer in the promoter region of the cystatin B gene. The unusually high GC content of this tract is refractory to conventional polymerase chain reaction (PCR), and, as a result, a circumventive procedure involving the deamination of DNA with sodium bisulfite has been proposed. This study evaluates the effectiveness of this deamination modification for the detection of dodecamer repeat variants. An analysis of 258 healthy Japanese individuals revealed an allele with four copies of the dodecamer repeat with a frequency of 0.01, in addition to the more commonly observed two and three copy repeat alleles. Homozygous repeat expansions 600 and 680 base pairs in length were detected in the analyses of two affected individuals. For these cases, sequencing, along with an alternative PCR-stutter formation, revealed 41 and 48 copies, respectively, of the dodecamer repeat. The complete conversion of C to T was observed in the expanded tracts, indicating that no methylation occurred at the CpG sites. Based on these results, it was concluded that the use of deaminated DNA allows for a precise analysis of consecutive GC tracts.

Antibacterial activity of Bacillus amyloliquefaciens phage endolysin without holin conjugation

To characterize the enzymatic activity and antibacterial activity of endolysin encoded by a Bacillus amyloliquefaciens phage, the open reading frame encoding endolysin was amplified by PCR and cloned into the expression plasmid pET21d(+). The resultant plasmid was used to transform Escherichia coli JM109(DE3). Production of endolysin in the cytosol facilitated cell lysis without coproduction of holin, which is considered to degrade or alter the cytoplasmic membrane. The phage endolysin was overexpressed and purified. Although the specific activity of the purified phage endolysin towards lyophilized Micrococcus luteus cells was 1/11 of the activity of chicken egg white lysozymes, the endolysin showed stronger antibacterial activity towards E. coli W3110, E. coli JM109(DE3) and Pseudomonas aeruginosa PAO1 than chicken egg white lysozymes. The antibacterial activity of the endolysin towards these three bacterial strains was marked when EDTA was added to the endolysin solution.

Near-threshold diffractive psi-meson photoproduction from the proton

Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes.

Relationship between stress factor and periodontal disease in a rural area population in Japan

OBJECTIVES

Several studies conducted in Western countries have shown significant associations between stress factors and periodontal disease. However, there have been only a few studies conducted in Asian countries. The present study was designed to identify possible relationship between stress and periodontal disease in residents of a rural area in Japan. -

MATERIAL AND METHODS

Data were collected from 1,089 adults with at least six natural teeth in a typical farming district of Japan. Subjects were asked to complete a questionnaire on daily stresses in various aspects of life. Data on gender, occupation, smoking, alcohol drinking habits, dental health behavior and systemic disease status were obtained from the questionnaires. Periodontal disease status was assessed using clinical attachment loss (CAL), and the subjects were dichotomized according to mean CAL<1.5 mm (control group) and>/=1.5 mm (diseased group). Logistic regression was applied to assess the associations between stress and other factors with periodontal disease, and odds ratios (ORs) as well as 95% confidence intervals were calculated.

RESULTS

In bivariate analysis, significant relationships were found between periodontal disease and stress within 1 month (P<0.001), job stress (P<0.001), self-health-related stress (P<0.001) and family health-related stress (P<0.01). Logistic regression analysis revealed that subjects who felt job stress (OR=1.71, P<0.05) and those who felt stress due to self health (OR=1.72, P<0.05) were more prone to have periodontal disease than were those who never or only rarely felt such stress. Significant correlations were also found between periodontal disease and smoking habit, frequency of dental clinic visits and hyperlipidemia (OR=1.8, P<0.05, OR=2.0, P<0.001, OR=2.1, P<0.05, respectively). -

CONCLUSION

The results suggest that stress related to self health and job might be potential risk indicators for development of periodontal diseases. Intervention measures including stress reduction may provide adjunctive approaches for preventing and treating periodontal disease.

Formation and resolution of ankylosis under application of recombinant human bone morphogenetic protein-2 (rhBMP-2) to class III furcation defects in cats

OBJECTIVES

Periodontal regeneration under application of bone morphogenetic protein (BMP) is compromised by ankylosis. Ankylosis disappearance following application of BMP has been observed in the case of a small defect, which might be beneficial change for periodontal regeneration. However, the histological observation of ankylosis disappearance has not been demonstrated in a large defect. The purpose of this present study was to confirm resolution of ankylosis during periodontal regeneration by recombinant human BMP-2 (rhBMP-2) applied to class III furcation defects.

MATERIAL AND METHODS

Class III furcation defects were created in the premolars of six adult cats. The rhBMP-2 material, prepared by applying rhBMP-2 to a combination of polylactic acid-polygricolic copolymer and gelatin sponge (PGS; 0.33 microg rhBMP-2/mm(3) PGS) or control material containing only PGS, was implanted into each defect. The cats were killed at 3, 6 or 12 weeks after surgery and serial sections were prepared for histological and histometrical observation.

RESULTS

Ankylosis was observed in some of the rhBMP-2/PGS group at 3 and 6 weeks, but not at 12 weeks. At 6 weeks, osteoclast-like cells were visible in the rhBMP-2/PGS group with ankylosis. Residual PGS was evident between the bone and root surface in the rhBMP-2/PGS group without ankylosis at 3 weeks.

CONCLUSIONS

Resolution of ankylosis by osteoclast-like cells possibly occurred under application of rhBMP-2. Residual PGS might play an important role in preventing ankylosis formation.

Estrogenic activity of 37 components of commercial sunscreen lotions evaluated by in vitro assays

Thirty-seven chemical components of commercial sunscreen lotions were evaluated for estrogen agonistic and/or antagonistic activity using two in vitro assays, (1) an ELISA-based estrogen receptor competitive binding assay (ER-ELISA) and (2) a modified yeast two-hybrid estrogen assay, with and without addition of a rat liver preparation, S9 mix. Eleven compounds, most of which were benzophenone derivatives and parabens, showed binding affinity to ER by ER-ELISA without S9 mix. Although the activities of almost all of the compounds were attenuated by addition of S9 mix, 4-octylphenylsalicylate and 2,2'-dihydroxy-4,4'-dimethoxybenzophenone acquired estrogenic activity, suggesting metabolic activation of these compounds. Two benzophenones showed agonistic activity in the yeast two-hybrid assay without S9 mix. The activity of one of these was reduced by S9 treatment and a further two benzophenones was activated. Eight parabens were active in this assay without S9 exposure, but their activities were eliminated by S9 treatment. Benzophenones with para-phenolic hydroxyl groups and parabens with branched and/or longer linear chains were generally more potent in both bioassays. In addition, weak antagonistic activity of 4-t-butylphenyl-salicylate, 2-ethylhexyl 4-dimethylaminobenzoate and (+/-)-alpha-tocopherolacetate was observed with S9 treatment. In vivo testing of the compounds reported here to have estrogen agonistic and antagonistic activities is required to confirm their effects at an organismal level.