The compact electron cyclotron resonance ion source KeiGM for the carbon ion therapy facility at Gunma University

A high-energy carbon-ion radiotherapy facility is under construction at Gunma University Heavy Ion Medical Centre (GHMC). Its design was based on a study of the heavy ion radiotherapy at the National Institute of Radiological Sciences (NIRS) in order to reduce the size and construction cost of the facility. A compact electron cyclotron resonance ion source (ECRIS) for Gunma University, called KeiGM, was installed in 2008. It is almost a copy of the prototype ECRIS Kei2 which was developed by NIRS; meanwhile this prototype produced over 1 e mA of C(4+) using C(2)H(2) gas (660 W and 40 kV). The beam intensity of C(4+) was 600 e microA with CH(4) gas (250 W and 30 kV). The beam intensity satisfies the required value of 300 e microA.

Application of positron emission tomography in physical medicine

Positron emission tomography (PET) is widely used in the fields of clinical and basic medicine. The PET device utilizes coincidence logic to detect annihilation photons emitted from positrons and estimates physiological functions of human organs in vivo. Radiopharmaceutical 18F- fluorodeoxyglucose (FDG), an analogue of glucose, is trapped metabolically in cells after being administered into the body, and can be substantially used for evaluating physiological and biochemical functions in vivo. Here, we attempted to describe the basics of PET as well as to apply the technique together with 18F-FDG as a tracer for evaluating organ glucose metabolism induced by exercise. Three-dimensional (3D) FDG-PET was applied to normal volunteers who performed exercise to evaluate whole-body glucose metabolism. Regions of interest analysis were drawn on visually defined regions (i.e., lower limbs, thigh, liver, intestine, brain, heart, etc.) to determine radioactivity distribution. FDG-PET clearly showed the recruitment of energy resources from abdominal organs to lower limb skeletal muscles to balance energy expenditures. The results suggested that 3D FDG-PET can be applied as an imaging tool to physical medicine.

Increased expression of Smad6 deteriorates murine acute experimental pancreatitis in two models

BACKGROUND

Smad6 is implicated in the inhibition of bone morphogenetic protein signalling. However, the function of Smad6 in the pancreas remains obscure.

METHODS

To elucidate the unknown function of Smad6, we developed transgenic mice selectively expressing Smad6 in pancreatic acinar cells using a plasmid construct coding rat elastase 1 enhancer/promoter.

RESULTS

Smad6 transgenic mice had no specific distinguishing phenotype such as body weight, pancreatic wet weight and concentrations of pancreatic protein. However, Smad6 transgenic mice reacted to hyperstimulation by caerulein injection or a diet containing 0.5% ethionine. Maximal amylase release stimulated by CCK-8 was significantly decreased in Smad6 transgenic mice acini, and trypsin activities in transgenic mice acini were significantly increased after stimulation of CCK-8. There was no difference in effect of CCK-8 stimulation on the subsequent increase in intracellular free Ca2+ concentration ([Ca2+](i)) between wild-type and transgenic mice acini. These findings suggest that reduced pancreatic enzyme secretion was caused by the disorder of its downstream signal transduction pathways in acinar cells. The amino acid sequence at the N-terminus of Smad6 was similar to that of synaptosome-associated protein (SNAP) 25 interacting protein, which plays an important role in regulating exocytosis of pancreatic enzymes in acinar cells. Pancreatic SNAP25 protein levels in transgenic mice were decreased after caerulein-induced pancreatitis.

CONCLUSIONS

These results suggest that elevated expression of Smad6 inhibits normal function of SNAP25-interacting protein and SNAP25, reduces amylase secretion in acinar cells, and increases the susceptibility of acinar cells to the onset of pancreatitis.

Mechanism of NKT cell activation by intranasal coadministration of alpha-galactosylceramide, which can induce cross-protection against influenza viruses

In a nasal vaccine against influenza, the activation of natural killer T (NKT) cells by intranasal coadministration of alpha-galactosylceramide (alpha-GalCer) can potently enhance protective immune responses. The results of this study show that the NKT cell-activated nasal vaccine can induce an effective cross-protection against different strains of influenza virus, including H5 type. To analyze the mechanism of NKT cell activation by this nasal vaccine, we prepared fluorescence-labeled alpha-GalCer by which we detect a direct interaction between NKT cells and alpha-GalCer-stored dendritic cells in nasal mucosa-associated tissues. Accordingly, although very few NKT cells exist at mucosa, the nasal vaccination induced a localized increase in NKT cell population, which is partly dependent on CXCL16/CXCR6. Furthermore, we found that NKT cell activation stimulates mucosal IgA production by a mechanism that is dependent on interleukin (IL)-4 production. These results strengthen the basis of nasal vaccination via NKT cell activation, which can induce immune cross-protection.

Endoscopic mucosal resection for early gastric cancer: comparison of two modifications of the cap method

BACKGROUND AND STUDY AIM

Endoscopic mucosal resection using a cap (EMR-C) is an established method for curative resection of early neoplastic lesions; prelooping of the snare may however be difficult and lead to imprecise resection. We therefore compared two modifications of the conventional technique using outer snare placement with an accessory channel in a prospective, nonrandomized study.

PATIENTS AND METHODS

Between October 2004 and March 2007, 54 patients (men 37, women 17; mean age 71 years) underwent EMR. One method involved an internally retained snare (IRS) cap, with a fixed prelooped snare inside the cap; the other method used an externally guided snare (EGS) cap with the snare guided over an oblique cap. The main outcome parameters were specimen size, en bloc resection, and complications.

RESULTS

There was no difference between use of the IRS and EGS cap methods in relation to specimen size (27.6 vs. 27.1 mm), or rates of en bloc resection (88.9 % vs. 83.3 %); only one perforation occurred, and this was in the EGS group.

CONCLUSION

Both techniques appeared to provide similar efficacy, the inner rim of the IRS cap stabilizes aspiration of the lesion compared with the EGS cap that does not have it.

Green tea polyphenol (-)-epigallocatechin-3-gallate inhibits ethanol-induced activation of pancreatic stellate cells

BACKGROUND

Activated pancreatic stellate cells (PSCs) play a central role in the pathogenesis of pancreatic fibrogenesis and inflammation. Ethanol, a major cause of chronic pancreatitis, directly induces PSC activation and oxidative stress. Inhibition of PSC activation or stimulation to PSC might be an effective therapeutic strategy for the prevention of pancreatic fibrosis, and (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea extracts, is a potent antioxidant of polyphenols. Therefore, we examined the mechanisms through which ethanol induces oxidative stress on PSCs and evaluated the effect of EGCG on activation and cell functions of ethanol-stimulated PSCs.

MATERIALS AND METHODS

The PSCs were isolated from the pancreas of male Wister rats with Nycodenz gradient methods and cells between passages one and four were used. Isolated PSCs were cultured with ethanol (50 mM) in the absence or presence of EGCG (5 microM or 25 microM).

RESULTS

The EGCG pre-treatment abolished ethanol-induced lipid peroxidation of the cell membrane, loss of total superoxide dismutase (SOD) activity and suppressed ethanol-induced gene expressions of Mn- and Cu/Zn-SOD. EGCG also suppressed ethanol-induced p38 mitogen-activated protein (MAP) kinase phosphorylation, alpha-smooth muscle actin production in PSCs and activated transforming growth factor-beta1 secretion into the medium. Furthermore, EGCG inhibited ethanol-induced type-I procollagen production and collagen secretion. In addition, EGCG inhibited transformation of freshly isolated cells to activated myofibroblast-like phenotype.

CONCLUSIONS

Our results suggest that green tea and polyphenols could prevent pancreatic fibrosis by inhibiting PSC activation through the antioxidative effect.

A short γ-ray burst apparently associated with an elliptical galaxy at redshift z = 0.225

Gamma-ray bursts (GRBs) come in two classes: long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift (z approximately 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars. In contrast, no short GRB had been accurately (< 10'') and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from--and the localization of--the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs.

Cholecystokinin-1 receptor protein up-regulation during pancreatic regeneration after acute haemorrhagic pancreatitis in rats

BACKGROUND

Cholecystokinin (CCK) plays an important role in regeneration after acute pancreatitis in rats. The present study was aimed to elucidate the role of CCK-1 receptor (CCK-1R) in acute pancreatitis. We investigated the serial changes in CCK-1R mRNA and protein levels and their immunolocalization after acute haemorrhagic pancreatitis induced in male Wistar rats by retrograde intraductal infusion of 4% sodium taurocholate (100 micro L 100 g(-1) body weight).

METHODS

Histological changes were evaluated by haematoxylin and eosin staining. Pancreatic CCK-1R mRNA was determined by Northern blot analysis. Pancreatic CCK-1R protein was evaluated by immunoblot analysis and immunohistochemistry with a polyclonal antibody against rat CCK-1R protein.

RESULTS

Histological findings revealed that newly formed acinar cells were detected at the periphery of tubular complexes on day 14, and normal architecture of lobules was observed focally on day 21. Pancreatic CCK-1R mRNA peaked on day 3 and thereafter gradually decreased. Cholecystokinin-1R protein rapidly increased after induction of pancreatitits, reaching a maximal level on day 3. On day 3, intense immunoreactivity for CCK-1R protein was observed in both the cytoplasm of vacuolized acinar cells and the tubular complexes. In the regenerative process after acute haemorrhagic pancreatitis in rats, the expression of pancreatic CCK-1R mRNA and protein increased, and intense immunoreactivity for CCK-1R protein was observed in tubular complexes in the cytoplasm of regenerated acinar cells.

CONCLUSION

These results suggest that CCK-1R contributes to pancreatic regeneration after acute haemorrhagic pancreatitis and that tubular complexes are involved in the process of acinar cell regeneration following pancreatic injury.

Attenuation of a human H9N2 influenza virus in mammalian host by reassortment with an avian influenza virus

In order to develop a surrogate virus strain for production of an inactivated influenza vaccine against a human H9N2 virus, A/Hong Kong/1073/99 (HK1073: H9N2) was co-infected in embryonated chicken eggs with an apathogenic avian influenza virus, A/Duck/Czechoslovakia/56 (Dk/Cz: H4N6), for gene segment reassortment. Multiple-gene reassortants obtained were examined for replication in mammalian hosts in vitro and in vivo by infecting MDCK cells and by intranasal administration to hamsters, respectively. A 2-6 gene reassortant with both surface glycoproteins of HK1073 origin and the rest of Dk/Cz origin, HK/CZ-13, was shown to replicate poorly in the mammalian hosts both in vivo and in vitro comparing with HK1073, although this reassortant replicated as efficiently as each parental strain in embryonated eggs. No sequence difference was observed in the HA1 region between HK1073 and HK/CZ-13, indicating that the reassortant would be equivalent in its immunogenicity to the parental HK1073 strain when it is used as an inactivated vaccine. A virus strain with attenuation in mammalian hosts is preferable for production of an H9 vaccine, since it should reduce the risk of manufacturing-related infections of employees during the vaccine production. HK/CZ-13 can therefore be a surrogate strain for production of an inactivated vaccine as well as diagnostic antigens in case of a possible future pandemic caused by an HK1073-like H9 influenza virus.

Neuraminidase sequence analysis and susceptibilities of influenza virus clinical isolates to zanamivir and oseltamivir

The influenza virus neuraminidase (NA) inhibitors zanamivir and oseltamivir were introduced into clinical practice in various parts of the world between 1999 and 2002. In order to monitor the potential development of resistance, the Neuraminidase Inhibitor Susceptibility Network was established to coordinate testing of clinical isolates collected through the World Health Organization influenza surveillance network from different regions of the world (M. Zambon and F. G. Hayden, Antivir. Res. 49:147-156, 2001). The present study establishes the baseline susceptibilities prior to and shortly after the introduction of the NA inhibitors. Over 1000 clinical influenza isolates recovered from 1996 to 1999 were tested. Susceptibilities were determined by enzyme inhibition assays with chemiluminescent or fluorescent substrates with known NA inhibitor-resistant viruses as controls. The 50% inhibitory concentrations (IC(50)s) depended upon the assay method, the drug tested, and the influenza virus subtype. By both assays, the mean zanamivir IC(50)s were 0.76, 1.82, and 2.28 nM for the subtype H1N1 (N1), H3N2 (N2), and B NAs, respectively, and the oseltamivir IC(50)s were 1.2, 0.5, and 8.8 nM for the N1, N2, and B NAs, respectively. The drug susceptibilities of known zanamivir- and oseltamivir-resistant viruses with the NA mutations E119V, R292K, H274Y, and R152K fell well outside the 95% confidence limits of the IC(50)s for all natural isolates. Sequence analysis of the NAs of viruses for which the IC(50)s were above the 95% confidence limits and several control isolates for which the IC(50)s were in the normal range revealed variations in some previously conserved residues, including D151, A203, T225, and E375 (N2 numbering). Known resistance mutations are both influenza virus subtype and drug specific, but there was no evidence of naturally occurring resistance to either drug in any of the isolates.