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Purpose Few studies have compared the implant quality of linked and loose seeds for prostate brachytherapy. This study aimed to evaluate and compare plan reproducibility of intraoperatively built custom linked seeds and loose seeds for prostate brachytherapy. Material and methods Between December 2010 and March 2014, 76 localized prostate cancer patients received Iodine-125 brachytherapy with external beam radiotherapy. Linked and loose seeds were implanted in 39 and 37 patients, respectively. The primary endpoint was the mean (± standard deviation) of the absolute change in the minimum dose received by 90% of the prostate volume between intraoperative and post-operative planning (ΔD90) to confirm plan reproducibility. Comparisons between the groups were evaluated using 2-sample t tests. Results The ΔD90 values were 6.95 ± 11.6% and -0.41 ± 8.5% for the loose and linked seed groups, respectively (p < 0.01). The linked seed group showed decreased post-operative D90 (118.8% vs. 127.2%), V150 (51.7% vs. 66.7%), and RV100 (0.44 ml vs. 0.61 ml) compared to the loose seed group (p < 0.01), whereas lung migration tended to be reduced (0% vs. 8%). Conclusions The plan reproducibility of the linked seed group was better than that of the loose seed group. Moreover, the linked seed group showed less migration and lower rectal dose.

Purpose To compare late genitourinary (GU) and gastrointestinal (GI) toxicity following different prostate cancer treatment modalities. Materials and methods This study included 1084 consecutive prostate cancer patients treated with conventional radiotherapy, intensity-modulated radiotherapy (IMRT), permanent iodine-125 implantation (PI) alone, and PI combined with external beam radiotherapy (PI+EBRT). The effects of treatment- and patient-related factors on late grade⩾2 (G2+) GU/GI toxicity risk were assessed. Results The median follow-up was 43months (range, 12–97months). Compared to the PI+EBRT, there was significantly less G2+ GU toxicity in the conventional radiotherapy (hazard ratio [HR]=0.39; 95% CI, 0.20–0.77) and the IMRT (HR=0.45, 95% CI, 0.27–0.73). Compared to the PI+EBRT, there was significantly more G2+ GI toxicity in the IMRT (HR=2.38; 95% CI, 1.16–4.87). In PI-related groups, prostate equivalent dose in 2Gy fractions was a significant predictor of G2+ GU toxicity ( p =0.001), and the rectal volume receiving more than 100% of the prescribed dose was a significant predictor of G2+ GI toxicity ( p =0.001). Conclusion The differences in the late G2+ GU/GI risk cannot be explained by the differences in treatment modalities themselves, but by the total radiation dose to the GU/GI tract, which had a causal role in the development of late G2+ GU/GI toxicity across all treatment modality groups.

Time-resolved fluorescence spectroscopy of tryptophan residue has been extensively applied to the studies on structure-function relationships of protein. Regardless of this, the fluorescence decay mechanism and kinetics of tryptophan residue in many proteins still remains unclear. Previous studies have demonstrated that conformational heterogeneity and relaxation dynamics are both involved in the peculiar multiexponential decay kinetics in subnanosecond resolution. In the present study, we characterized the fluorescence decay property of six indole compounds in glycerol by resolving the contribution of conformational heterogeneity and relaxation dynamics. We applied the time-resolved area-normalized fluorescence emission spectrum (TRANES) method for the fluorescence decay analysis. The results of TRANES, time-dependent shift of fluorescence spectral center of gravity, and fluorescence decay simulation demonstrated that the dielectric relaxation process independent of intrinsic rotamer/conformer and the individual fluorescence lifetime gives the peculiarity to the fluorescence decay of indole compounds. These results confirmed that TRANES and time-dependent spectral shift analysis are potent methods to resolve the origin of multiexponential decay kinetics of tryptophyl fluorescence in protein.

The conformation and dynamics of a protein are essential in characterizing the protein folding/unfolding intermediate state. They are closely involved in the packing and site-specific interactions of peptide elements to build and stabilize the tertiary structure of the protein. In this study, it was confirmed that trypsin inhibitor obtained from seeds of bitter gourd (BGTI) adopted a peculiar but plausible conformation and dynamics in the unfolding intermediate state. The fluorescence spectrum of one of two tryptophan residues of BGTI, Trp9, shifted to the blue side in the presence of 2-3 M guanidine hydrochloride, although the other, Trp54, did not show this spectral shift. At the same time, the motional freedom of Trp9 revealed by a time-resolved fluorescence study decreased, suggesting that the segmental motion of this residue was more restricted. These results indicate that BGTI takes such a conformation state that the hydrophobic core and loop domains arranging Trp9 and Trp54 respectively are heterogeneously packed in the unfolding intermediate state.

Intermolecular interactions between protein molecules diffusing in various environments underlie many biological processes as well as control protein crystallization, which is a crucial step in x-ray protein structure determinations. Protein interactions were investigated through protein rotational diffusion analysis. First, it was confirmed that tetragonal lysozyme crystals containing fluorescein-tagged lysozyme were successfully formed with the same morphology as that of native protein. Using this nondisruptive fluorescent tracer system, we characterized the effects of sodium chloride and ammonium sulfate concentrations on lysozyme-lysozyme interactions by steady-state and time-resolved fluorescence anisotropy measurements and the introduction of a novel interaction parameter, krot. The results suggested that the specific attractive interaction, which was reflected in the retardation of the protein rotational diffusion, was induced depending on the salt type and its concentration. The change in the attractive interactions also correlated with the crystallization/precipitation behavior of lysozyme. Moreover, we discuss the validity of our rotational diffusion analysis through comparison with the osmotic second virial coefficient, B22, previously reported for lysozyme and those estimated from krot.

Snowmelt runoff is a precious water resource in cold region. However it causes disasters by influence of a warm air and a rainfall in spring. Therefore accurate estimation of snow water equivalent and forecast of snowmelt discharge are vital for river management. We investigated how snow water equivalent changes with time in the Jozankei Dam basin and on the premises of the Ishikari Experiment Laboratory. It was done by continuously monitoring of snowcover weight and snowmelt discharge using snowcover weightmeters and lysimeters. We observed time-lag of snowmelt runoff and excessive snowmelt runoff. It was caused by structure of snowcover layer. We proposed a simple equation for estimation of snow density by multiple linear regression analysis. We estimated snow water equivalent in the Jozankei dam basin by using the equation. The result of estimation is almost satisfactory.

Approximately half of the precipitation in Hokkaido falls as snow, and snowmelt floods in spring are an important factor in the river environment and in flood control and other river management. In Hokkaido, water storage at dams is managed using snowmelt water, and accurate estimation of snow water equivalent is important for flood management. We investigated how snow water equivalent changes with time in the Jozankei Dam basin, a basin that typifies those in snowy regions. Investigation was done by continuously monitoring snowcover weight and melted weight using a snowcover weightometer, which allows direct measurement of snowcover weight, and other instruments. Temporal changes in snow water equivalent and snow density were identified. The snow density was around 0.2g/cm3 at the initial stage of snow-accumulation, but at the late stage, the snow became granular in all layers and its density stabilized at around 0.4-0.5 g/cm3.

This study evaluates the living environment for Oncorhynchus masou parr by their feeding activities. Knowledge on physiology and ecology of Oncorhynchus masou parr is used for calculation of acquired energy after feeding, and consumed energy for maintaining their position and resting against current. The balance between the two kinds of energy is also calculated. The evaluation result can be applied for relative evaluation of the living environment of each section that show different environmental data, and for quantitative estimation of fish habitation in other rivers. To support this, the study verifies the validity of the evaluation by analyzing pools and riffles in the studied sections of the river, and the relationship between the energy balance and fish population in the river channel. And we clarified the optimal environmental conditions for Oncorhynchus masou.

The ribonuclease P (RNase P) in the hyperthermophilic archaeon Pyrococcus horikoshii comprises RNA (PhopRNA) and five proteins. We analyzed the RNA binding mode of the protein, using a pair of complementary fluorescence-labeled oligoribonucleotides. Fluorescence resonance energy transfer (FRET)-based assays suggested that the RNase P proteins assist PhopRNA in attaining a functionally active conformation via a distinct mode of binding.

The fluorescence spectral distributions of four tryptophan residues of hen egg-white lysozyme were analyzed using time-resolved and quenching-resolved fluorescence spectroscopy. Trp62 and Trp108 gave the fluorescence maxima at 352 nm and 342 nm, respectively. The fluorescence of Trp28 and Trp111 occurred only at 300-360 nm and they were observed as an unresolved emission band with a maximum and shoulder at 320 nm and 330 nm. The fluorescence quenching and decay parameters of each tryptophan residue reconfirmed that Trp62 was fully exposed to the solvent but Trp108 was sealed in the cage of the peptide chains and furthermore showed that Trp28 and Trp111 are under the influence of the larger fluctuational motion at the hydrophobic matrix box. The fluorescence responses of each tryptophan residue to the lysozyme-ligand interaction suggested that the internal fluctuation was reduced by the binding of ligand to give a distorted conformation to the hydrophobic matrix box region.

In Escherichia coli the oriC-independent primosome plays an essential role in replication restart after dissociation of the replication DNA–protein complex by DNA damage. Primosome is thought to form via two pathways: one PriA dependent and the other PriA independent. PriC is a key protein in the replication restart of the PriA-independent pathway. In this study, we determined that PriC was divided into two domains. Then, we obtained information that: (i) the C-terminal domain preferentially binds to single-stranded DNA (ssDNA); (ii) the binding of PriC to ssDNA depends on salt concentration; and (iii) the binding site size of PriC is approximately 7–9 nucleotides. The protease digestion of PriC suggested that a possible DNA-binding site is the N-terminus of the C-terminal domain where basic amino acid residues are concentrated. Interestingly, α-helical induction of the C-terminal domain of PriC occurred after the addition of DNAs. Also, we examined the role of heptad repeat of leucine or valine residues in the C-terminal domain and PriC oligomerization. This study describes the structure and function analysis of PriC which forms the primosome complex in replication restart.

The cationic derivatives, the hydrochloride salts of ethylenediamine monodeoxycholate (EdaDC) and cholate (EdaC) derived from the respective bile salts, sodium deoxycholate (NaDC) and cholate (NaC), were synthesized and their physicochemical and biological properties together with the possibility of application as crystallizing agents for membrane proteins were studied. The critical micelle concentrations (CMCs) in water were determined to be 4.0 mM for EdaDC and 9.0 mM for EdaC, and the surface tensions were lowered down to 43 and 41 mN m−1, respectively, in the range above CMCs. When compared with the corresponding natural bile salts, the two cationic bile acid derivatives have the highest surfactant ability, followed by the corresponding taurine-conjugated salts of TDC (taurodeoxycholic acid) and TC (taurocholic acid) and the free bile acid salts of DC and C have the lowest activity. Studies of dye release from pre-encapsulated vesicles, hemolysis and antimicrobial activity indicated that the concentrations leading to a large increase in the membrane permeability and biomembrane perturbation ability are signiicantly lower than the CMCs of these surfactants. Buffer solution containing EdaC or EdaDC could solubilize a membrane protein, light-harvesting chlorophyll ab protein complex (LHCII), at concentrations higher than CMCs, but the power was estimated to be one third of that of surfactants such as Triton X-100, n-octyl-β-d-glucopyranoside and n-nonyl-β-d-glucopyranoside. Fluroescence depolarization studies showed that some specific molecular interactions between LHCIIs are induced by the cationic bile salts, suggesting that the latter would be valid for the crystallization of LHCII. In fact, LHCII crystals were observed in crystallization media containing 1% EdaC or 0.5% EdaDC.

The hydraulic characteristics of an ice-covered river is much different from those at other seasons, because the frictional resistance between water surface and icesheet increases due to the ice cover on the water surface.Accuracy of estimation of the average velocity is dependent on the velocity profile. Usually, the k-e model is used to estimate the velocity profile under ice cover. This paper verifies a new estimation of a velocity profile under ice, the Two-Power LAW, using data measured in Hokkaido.

Protein intermolecular depletion interactions induced by polyethylene glycol (PEG) depend largely on its concentration and molecular weight. Herein, we investigated the effects of various concentrations and molecular weights of PEG on lysozyme interactions through the analysis of protein rotational diffusion, which is susceptible to intermolecular interactions at short range. To this end, we measured fluorescence anisotropy of fluorescein-tagged lysozyme added as a tracer in concentrated native lysozyme solutions and introduced a protein concentration-dependent interaction parameter, k(rot). The results show the nonmonotonic changes in k(rot) as the concentrations of PEG10000 and 6000 are increased. The depletion attractions are characterized by the decrease in k(rot), indicating an increase of a degree at which protein rotational diffusion slows down. The influences of temperature on the lysozyme rotational diffusion and k(rot) were also measured, and the validity of this approach was checked through comparison with the colloidal theory.

Pyruvate dehydrogenase multienzyme complex was purified from Bacillus caldolyticus. The complex was composed of four polypeptides with molecular masses of 39.8, 41.7, 53.7, and 57.5kDa estimated by SDS-PAGE and they were presumed to be pyruvate decarboxylase (E1, dimeric), lipoate acetyltransferase (E2), and lipoamide dehydrogenase (E3) on the analogy of those from Bacillus stearothermophilus. E1 and E3 were stable at pH 5.7-10.2 and 4.5-11.3, respectively. Halves of E1 and E3 activity were abolished by incubation for 30min at 65°C and 85°C, respectively. Loss of overall activity was principally due to inactivation of E1. Structural changes in the complex incubated at high temperature were studied by fluorescence spectroscopy. The results suggested that the thermal denaturation of the complex proceeded through at least two different steps: inactivations of E1 and E3, and the former process is accompanied by a reduction of the complex size.

With reference to the local conformation of a protein, it is interesting to differentiate the individual fluorescence properties of included tryptophan residues without modification. The fluorescence spectrum of bitter gourd trypsin inhibitor (BGTI) was separated into two emission bands by the quenching-resolved fluorescence method. One emission band was given as a fraction with the Stern-Volmer quenching constant, 44.9 x 10(-3) M(-1), against the fluorescence quenching by KI, and it showed an emission maximum intensity at 341 nm. The fluorescence quenching constant of the other band was 1.58 x 10(-3) M(-1), and the maximum wavelength was found at 337 nm. These separated emissions were due to the fluorescence of Trp54 and Trp9 of BGTI. The quenching resolved-fluorescence spectrum was effectively applied to the precise description of the polar circumstances surrounding the Trp residues in the unfolding intermediate state of BGTI. The results suggested that the molten globule-like state of BGTI adopted such a peculiar conformation that the helix domain including Trp9 was packed more densely while the other loop domain partially unfolded.

Field measurements of velocity profiles for ice-covered streams were performed in Hokkaido. Surface conditions of the cover were classified into smooth ice cover, rippled ice cover and cover with frazil slush. Adaptability of logarithmic velocity distribution was first investigated. The friction factor fi and Manning's roughness coefficient ni were caluculated based on an assumption of the logarithmic distribution; average values ni for smooth and rippled cover were 0.012 and 0.021 respectively.

The electronic structures of models for alkylene-aromatic polymers (AAPs) and their pyrolysis products, as member of the one-dimensional graphite family, have been studied on the basis of tight-binding crystal orbital calculations. The band gaps of AAPs decrease and the frontier-band widths increase with the progress of the pyrolysis. The change of the frontier electron distribution has also been examined.

Stereotactic radiosurgery (SRS: single-fraction stereotactic irradiation) was originally developed to treat benign lesions in the brain, and has been adopted for the treatment of small primary or metastatic brain tumours. It has recently been recommended that stereotactic radiotherapy (SRT: fractionated stereotactic irradiation) be applied to the treatment of brain tumours; however, it requires much more time and work than SRS, and sufficient radiobiological evaluations of these techniques have never been carried out. Biologically effective doses were calculated to determine the indications for SRS and SRT, and to decide on an effective SRT schedule, incorporating the factors of 'repair' and 'cell proliferation'. The results suggest that SRS would be recommended for arteriovenous malformations and benign tumours that have distinct margins separating them from surrounding normal tissue and SRT would be recommended for benign or malignant brain tumours without clearly defined boundaries. The recommended SRT schedules would be 7 Gy x 7 fractions every other day for malignant tumours and 3.5 Gy x 12 fractions every other day for benign tumours. However, clinically, these schedules should be modified according to many other factors in individual cases.

Upon heat treatment of the pyruvate dehydrogenase complex from Bacillus stearothermophilus, the most thermostable component is a dihydrolipoamide dehydrogenase (E3c). To understand this stability, the thermal disintegration of E3 dissociated from the complex (E3d) was examined, comparing with that of E3c. Judging from residual activity and inactivation rate, E3d was less thermostable than E3c; E3d and E3c lost half of their original activities upon incubations for 30 min at 79 degrees C and 90 degrees C, respectively. Heat treatment of E3d raised the fluorescence intensities of Trp residue, intrinsic FAD, and extrinsic 8-anilinonaphthalene-1-sulfonate. E3d lost FAD, and inactive E3d polypeptides were aggregated. The sulfonate bound to the aggregate became notably fluorescent. The thermal disintegration of E3d was speculated to be a consecutive reaction that was different from the concurrent disintegration reaction of the complex. Some interactions with other component polypeptides was suggested to improve the thermostability of E3c.

By analyzing the steady state and time-resolved fluorescence anisotropy, the internal motions of chlorophyll a of light-harvesting chlorophyll a/b-protein complex (LHCII) were characterized in a dimyristoylphosphatidylcholine (DMPC) liposome. Corresponding to the thermotropic phase of the membrane, chlorophyll a showed an unique internal motion in LHCII. At the gel phase, two motional components, one fast and the other slow, were observed, which would originate in the heterogeneity of the mutual orientation and the binding site of the chlorophyll a in LHCII. Interestingly, the faster motion was suppressed and only the slower segmental rotation with the larger motional amplitude was allowed on the phase transition to a liquid crystalline phase.

Thermally induced changes in pyruvate dehydrogenase complex (PDC) from B. stearothermophilus were examined mainly at temperatures from 60 degrees to 70 degrees C. Accompanied by inactivation of pyruvate decarboxylase, light scattering decreased, and ANS fluorescence increased. These changes including the inactivation were approximately first-order reactions, and the values of rate constants were greatly dependent on temperature. Chromatographic studies showed that any polypeptides were in associated forms and that final products were aggregates (230S) and an assembly (48S) smaller than PDC. The aggregates and assembly were rich in decarboxylase and lipoate acetyltransferase, respectively. It was suggested that, during the thermal denaturation, a decarboxylase was dissociated from PDC and immediately involved in aggregates.

The conformational change of hen egg-white lysozyme (EC 3.2.1.17) induced by the interaction with tri-N-acetyl-D-glucosamine were investigated by steady state and time-resolved fluorescence spectroscopy. To identify more clearly the conformation of hen egg-white lysozyme interacting with the ligand, the fluorescence decay kinetics of the lysozyme and its complex with the ligand were precisely measured at their full spectral regions. The spectral analysis based on the time-resolved studies showed that the binding of the ligand affected not only the Trp62 directly linked to the ligand but its influence was extended to the vicinity of Trp108 and further to the hydrophobic matrix box region. Near the binding site, the intramolecular distance between Trp108 and Glu35 was expanded or contracted depending on the pH of the buffer solution. On the other hand, the interaction of Trp28 and/or Trp111 with their surroundings was reduced by restriction of fluctuational motions at the hydrophobic matrix box region.

Since 2004, stationary SOFC CHP systems using flatten tubular segmented-in-series (FT-SIS) cells stacks have been developed by Tokyo Gas Co., Ltd., Gastar Co., Ltd., Rinnai Corporation and Kyocera Corporation to construct small-scale CHP systems which excel in performance and durability. In 2008, we have succeeded in producing a residential system which consists of a power generation unit using FT-SIS cells stacks and a heat recovery unit. Electric power and hot water are produced efficiently in the system, and by adopting electric load following operation, the produced energy is supplied to the residence with minimal loss. Since 2009, we have installed the systems into residences to collect operation data under practical use conditions. A part of the tests are conducted under NEDO SOFC Demonstration Program. From the operational data, environmentally-enhancing potentials and superior durability of the FT-SIS SOFC systems are verified.

The dynamical properties of subsite C of hen egg-white lysozyme were investigated using Kyn62-lysozyme as an active analogue. Time-resolved fluorescence depolarization studies showed that the segmental motion of kynurenine which was important in subsite C was described with two components of which the rotational correlation times were phi 1 = 150 ps and phi 2 = 1.4 ns, respectively. Although these two segmental motions retained 90% of motional freedom, the slower motion was completely restricted and the degree of freedom was lost to 40% during the interaction with oligomers of N-acetyl-D-glucosamine.

Thermostabilities of component enzymes in the pyruvate dehydrogenase complex from Bacillus stearothermophilus decreased in the order lipoamide dehydrogenase, lipoate acetyltransferase, and pyruvate decarboxylase (E1). Fluorescence of an extrinsic 8-amino-1-naphthalenesulfonate (ANS) increased with inactivation of E1. The thermal denaturation of the enzymes resulted in disassembly of the complex. El was involved in a resulting aggregate of the complex. The interaction between ANS and denatured E1 accounted for an increase in fluorescence.