PHOTON FIELD OF ~100-200 KEV FOR ENVIRONMENTAL DOSEMETER CALIBRATION

As a reference photon field, several radionuclides have been used frequently, such as 241Am,137Cs and60 Co for calibration. These nuclides provide mono-energy photons for dosemeters covering few tens of keV-MeV. The main energy around 200 keV is important for both environmental and medical fields since the former should consider scattering photons and the later should measure photons from X-ray generator. In our previous work, a backscattered layout can provide a uniform photon field spectra and dose rate with an energy of 190 keV by using an affordable intensity 137 Cs gamma source. Several other quasi-monoenergetic photon fields in the range of 100-200 keV could be obtained by using several available gamma sources. Two calibrated environmental CsI(Tl) survey meters, Horiba PA-1000 and Mr. Gamma A2700, had been measured with the developed backscattered photon field to understand energy-dependent features in order to confirm dosemeter readings. Consequently, both scintillator instruments are sensitive for measurements of the relatively low dose rates at 190 keV.

78 Evaluation of the genomic estimated breeding value of carcass traits in blastocyst-stage embryos derived from Japanese Black cattle

Genomic selection based on a high-throughput microarray for genotyping single nucleotide polymorphism (SNP) is expected to accelerate genetic improvement in cattle. Recently, a genomic evaluation system for carcass traits, such as carcass weight and marbling score, is being established in Japanese Black cattle. To further increase genetic improvement efficiency in this breed, establishing a genomic evaluation system for pre-implantation embryos before embryo transfer (ET) is required. Here, we examined the correlation between genomic estimated breeding value (GEBV) of carcass traits calculated from embryonic (blastocyst) biopsy cells and from a corresponding calf produced by ET (Experiment 1); we also evaluated the pregnancy rate following ET of GEBV-evaluated blastocysts (GEBV blastocysts) preserved by vitrification (Experiment 2). In total, 16 Japanese Black dams and cryopreserved semen from 6 Japanese Black sires were used for producing in vivo blastocysts (Day 7-8). In Experiment 1, four blastocysts (IETS code 1) were divided into biopsy cells (15-20 cells) and biopsied embryos using a micromanipulator equipped with a micro blade. Biopsy cells were processed for DNA extraction and whole-genome amplification. Freshly biopsied embryos were transferred to recipient cows, and DNA was extracted from the blood or ear cells of the resulting 4 calves. Then SNP genotyping was performed using Illumina bovine LD BeadChip (Illumina, San Diego, CA, USA). The GEBV of 6 carcass traits (carcass weight, ribeye area, rib thickness, subcutaneous fat thickness, estimated yield percent, and marbling score) were calculated using phenotypic and genotypic data from 4,311 Japanese Black steers, and these were compared between biopsy cells and the corresponding calf. In Experiment 2, 134 blastocysts (IETS code 1 and 2) in total were biopsied (10-20 cells), and the biopsied embryos were vitrified by the cryotop method. Biopsy cells were processed for SNP genotyping as in Experiment 1, and the samples in which the call rate was more than 85% were used for GEBV calculation. Based on GEBV records, 24 vitrified GEBV blastocysts were warmed, cultured for 3 to 5h, and 22 GEBV blastocysts that survived (re-expanded) post-culture were transferred to recipient cows. Pregnancy in these cows was diagnosed using ultrasonography during Day 55 to 60 of gestation. In Experiment 1, the SNP call rates of the biopsy cells and corresponding calf were 98.5 to 99.3% and 99.7 to 99.8%, respectively. The GEBV of 6 carcass traits from biopsy cells and from the corresponding calf had almost the same values. In Experiment 2, the SNP call rates of the biopsy cells were ranged from 26.1 to 99.3%. The GEBV of 6 carcass traits varied among full-sib embryos. The pregnancy rate following ET of vitrified GEBV blastocysts was 40.9% (9/22). These results suggest the possible application of a genomic evaluation system for carcass traits at the blastocyst stage in Japanese Black cattle. Further large-scale assessment of pregnancy rates following ET of cryopreserved GEBV blastocysts is required for practical application of the evaluation system.

The muscular dystrophic chicken is hypernatremic

1. The E3 ubiquitin protein ligase 1 (WWP1) gene, the mutation of which causes muscular dystrophy in chickens, is expressed not only in the pectoral muscle, but also in a number of tissues such as the kidney. Therefore, this study examined some parameters related to kidney function in muscular dystrophic (MD) chickens. 2. Plasma osmolality, Na⁺ and K⁺ concentrations, aldosterone levels, and the expression of aquaporin (AQP) 2, AQP3, and α subunits of the amiloride-sensitive epithelial sodium channel (αENaC) were analysed in the kidneys of 5-week-old MD chickens and White Leghorn (WL) chickens under physiological conditions or after one day of water deprivation. 3. Plasma osmolality, Na⁺ concentrations, and plasma aldosterone levels were significantly higher in MD chickens than in WL chickens. αENaC mRNA expression levels were lower in MD chickens than in WL chickens. AQP2 and AQP3 mRNA expression levels were similar in the two strains of chickens. 4. Plasma osmolality correlated with aldosterone levels and AQP2 and αENaC mRNA levels in WL chickens. In MD chickens, plasma osmolality correlated with AQP2 mRNA levels, but not with plasma aldosterone or αENaC mRNA levels. 5. These results suggest that neither water reabsorption nor the expression of AQP2 and AQP3 is impaired in MD chickens and that a WWP1 gene mutation may or may not directly induce an abnormality in Na⁺-reabsorption in the kidneys of MD chickens, potentially through αENaC.

141 EXPRESSION STATUS OF AQUAPORINS 3, 7, AND 9 IN BOVINE PRE-IMPLANTATION EMBRYOS

The aquaporins (AQP) are a family of small integral membrane proteins that work as channels for rapid water transport. In mouse embryos, AQP3, AQP7, and AQP9 were found to play important roles in the pre-implantation development or adaptive cellular response to osmotic stress. In addition, because AQP3, AQP7, and AQP9 permeate not only water but also cryoprotectant, such as glycerol, these AQP thought to be involved in the process of cryopreservation. However, little information is available for AQP in bovine embryos. The understanding of the mechanisms mediated by AQP that embryos utilise to survive during culture and the process of cryopreservation will contribute to development of in vitro culture systems and cryopreservation procedures for bovine embryos. The aims of present study were to clarify the expression status of AQP3, AQP7, and AQP9 in bovine pre-implantation embryos, and to evaluate the expression level of AQP3 in in vivo-derived (IVD) and IVF bovine embryos. For production of IVF embryos, cumulus-oocyte complexes (COC) were aspirated from ovaries collected at a local slaughterhouse. The COC were in vitro matured, fertilized, and then cultured for 7 days. The IVD embryos at early blastocyst (EB) and blastocyst (BC) stage were obtained from donor cows treated with superovulation and AI. In experiment 1, in order to clarify the expression of AQP3, AQP7, and AQP9 mRNA in bovine pre-implantation embryos, total RNA was extracted from pools of 30 IVM oocytes, pools of 15 IVF embryos at 2- to 4-cell, 8- to 16-cell, compaction morula (CM), EB, BC, and expanded blastocyst (ExBC) stage, and RT-PCR was performed followed by agarose gel electrophoresis. In experiment 2, in order to clarify the expression status of AQP3, AQP7, and AQP9 during bovine pre-implantation development after zygotic gene activation, total RNA was extracted from pools of 15 IVF embryos at 8- to 16-cell, CM, EB, BC and ExBC stage (n = 5), and relative quantifications of AQP mRNA were performed using real-time RT-PCR. Data were analysed by Scheffé’s method. In experiment 3, AQP3 transcript levels in single IVD and IVF embryos at EB and BC stages (n = 10) was evaluated by real-time RT-PCR. Data were analysed by Mann-Whitney’s U test. In experiment 1, AQP3 and AQP7 transcripts were detected in IVM oocytes and all stages of embryos. AQP9 mRNA was detected in IVM oocytes and in 2- to 4-cell, 8- to 16 cell, CM, and EB stage embryos, but was not detected in BC and ExBC stage embryos. In experiment 2, AQP3 and AQP7 transcript levels were significantly increased from 8- to 16-cell to CM and EB stage, and significantly decreased from EB to BC and ExBC stages (P < 0.05). AQP9 transcript level was significantly decreased from 8- to 16-cell to CM and EB stage (P < 0.05). In experiment 3, AQP3 transcript level in IVF embryos was significantly lower than that in in vivo embryos at the BC stage (P < 0.05). Our results indicate that AQP3 and AQP7 may have specific roles at morula and EB stage in bovine embryos. In addition, AQP3 expression is influenced by developmental condition of bovine embryos.

Direct observation of back energy transfer in blue phosphorescent materials for organic light emitting diodes by time-resolved optical waveguide spectroscopy

We demonstrate a high-sensitive transient absorption technique for detection of excited states in an organic thin film by time-resolved optical waveguide spectroscopy. By using a laser beam as a probe light, we detect small change in the transient absorbance which is equivalent to 10^-7 absorbance unit in a conventional method. This technique was applied to organic thin films of blue phosphorescent materials for organic light emitting diodes. We directly observed the back energy transfer from emitting guest molecules to conductive host molecules.

Computation of diffusion limited controlled actions for gene regulating repressor particles

Temporal changes in association anddissociation kinetics of the repressor -operator reaction were simulated by a computational approach using MATOLABO on the basis of strict mathematical description. The diffusion equation of a repressor particle has been combinedwith arrival probabilities of therepressor particle. Temporal behaviors of the repressor operator complex have been computed by inverting the Laplace transformed equations. The temporal kinetic data of association anddissociation obtained at differentionic strength and at different DNA length were successfully simulated. Those results could be achieved byregulating diffusion constants inmedium on the DNA, a reaction radius of the repressor and a reaction rate per one repressor on the reaction sphere surface, k value. The reported values of association rate constant ka obtained at different ionic strength were also successfully simulated. Amongthe regulated parameters to get these successful simulations, the reaction rate per one particle on the reaction sphere surface, k value has effectiveinfluences on the association anddissociation kinetics particularly those at varying ionic strength that were induced by high KCl condition. By an electro chemical consideration for thechange of k value in combinationwith the screening effects of counter ions around the repressor particle and the DNA molecule, the most effectivefactor seems to be the Coulombrepulsive forces and or Londondispersion forces. The sliding mechanism for facilitated translocation of a repressor protein ona DNA chain can be described by the present mathematical approach which describes the temporal changes in amounts of the species. To achieve such mechanism in varying ionic strength,the secondary changes in the diffusion constants, the reaction radius and the reaction rate per one particle on thereaction sphere surface k value (anelectro chemical factor) seemed to have important roles.

Calculation of personal dose equivalent for positron-emitting radionuclides using Monte Carlo code EGS5

The conversion coefficients, H'(d,α)/Φ, for monoenergetic positrons and positron-emitting radionuclides were calculated by using the user code UCICRPM of the Monte Carlo code EGS5 to estimate the radiation dose for medical staff involved in positron emission tomography examinations. From these coefficients, the dose equivalent rates per unit activity at 0.07 and 10 mm depths in a soft tissue for a straight-line source of 2-deoxy-2-[(18)F]fluoro-d-glucose ((18)F-FDG) were calculated by using the developed user code UCF18DOSE. The dose equivalent rates per unit activity at 0.07 and 10 mm depths were measured by using a personal dosemeter (DOSE(3)) under the same conditions as those considered in the calculation. The calculated dose equivalent rates per unit activity at 0.07 and 10 mm depths were 0.116 and 0.0352 pSv min(-1) Bq(-1), respectively, at 20 cm from the (18)F-FDG injection tube.

High Efficiency UV-Emission at 345 nm from InAlGaN Light-Emitting Diodes

Optical and electrical properties of 340 nm-band bright UV-light emitting diodes (LEDs) were compared between In0.03Al0.20Ga0.77N and other active regions. Single peaked and high efficiency ultraviolet (UV) emission at 345 nm from In0.03Al0.20Ga0.77N LEDs is achieved under continuous current injection conditions. Any significant broadening and peak shift of the electroluminescence (EL) spectrum were not observed. We attribute such a good properties to using of high quality InAlGaN-quaternary active layer. The EL intensity of the InAlGaN quaternary-based LED showed more one order of magnitude higher intensity than that of AlGaN and GaN based LEDs. Additionally, The I-L characteristics of the InAlGaN quaternary-based LED showed a linearly increasing of intensity with increasing of injection current density, that is also observed for InGaN based LEDs. This shows the recombination efficiency of the InAlGaN-based LED is as much as that of InGaN based LEDs. From these results InAlGaN quaternary is expected to be a promising material for UV LEDs and LDs.

Fabrication of p-n junction with Mg-doped wide bandgap InAlGaN for application to UV emitters

Mg-doped quaternary InAlGaN is very attractive for use as p-side layers of 300-nm band ultraviolet (UV) light-emitting diodes (LEDs) or laser diodes (LDs), because high hole conductivity is expected to obtain for wide bandgap (~4 eV) InAlGaN with Mg-doping. We fabricated p-n junction diode consisting of Mg-doped In0.02Al0.28Ga0.70N and Si-doped Al0.25Ga0.75N, and demonstrated intense UV emission under CW current injection at room temperature. The rising voltage in I-V curve was around 3.8 V and the breakdown voltage was as high as 10 V. Single peaked intense emission was observed at 340 nm from around InAlGaN/AlGaN p-n junction area without any deep level emission. Also we found that Ni/Au electrode directly fabricated on Mg-doped InAlGaN is useful. From these results, Mg-doped InAlGaN is considered to be very attractive for use as p-side layer of UV-LEDs or LDs.

Gas Source Silicon Molecular Beam Epitaxy

Gas source silicon molecular beam epitaxial (Si-MBE) growth is microscopically governed by a disociative adsorption of silicon hydrides, such as Si2H6 source gas molecules on Si surface. The dissociative adsorption generates SiH species on the surface. From this hydride phase, hydrogen desorbs thermaly. The temperature dependence of the growth rate indicated that the hydrogen desorption from the SiH is the rate limiting step. In HBO2 Knudsen cell doping, B adsorbates block the surface migration. Such a blocking effect can be avoided by B2H6 gas dopant, because of the similar incorpration mechanism of B2H6 to that of Si2H6. However, in PH3 gas doping, a crystal quality degradation was observed at a high doping range due to the preferentially high sticking coefficient of PH3 and the resulting surface dangling bond termination. The selective epitaxial growth of a B doped layer using Si2H6 and B2H6 was applied to a novel structured base fabrication for super self-aligned selectively grown base transistor (SSSBT). A successful achievement of the SSSBT fabrication indicates the high potentiality of gas source Si-MBE to the sub-micron size ultra-high speed bipolar large scale integrated (LSI) circuits.

Contrasting effects of ghrelin and des-acyl ghrelin on the lumbo-sacral defecation center and regulation of colorectal motility in rats

BACKGROUND

We have previously demonstrated that a centrally penetrant ghrelin receptor agonist enhances colorectal motility, through activation of the lumbo-sacral defecation center (L6-S1 region of the spinal cord) in rats. In the present study, we examined the effects of the native peptide and its non-acylated counterpart in eliciting this stimulatory effect on colorectal motility.

METHODS

Rats were anesthetised with α-chloralose and ketamine, and colorectal intraluminal pressure and propelled intraluminal liquid volume were recorded in vivo.

KEY RESULTS

Intrathecal application of acylated ghrelin to the L6-S1 region of the spinal cord, but not intravenous application, elicited groups of phasic increases in colorectal intraluminal pressure that were associated with increased fluid output through the anal cannula. The effect was dose-dependent. The colokinetic effects of ghrelin were prevented if the pelvic nerves were severed. Reverse transcription polymerase chain reaction revealed the expression of the ghrelin and ghrelin receptor genes in the lumbo-sacral spinal cord. In contrast to acylated ghrelin, des-acyl ghrelin failed to cause changes in colorectal motility. However, when des-acyl ghrelin and ghrelin were applied simultaneously at the L6-S1 region, the ghrelin-induced enhancement of colorectal motility was significantly attenuated.

CONCLUSION & INFERENCES

It is concluded that acylation of the ghrelin peptide is essential to promote propulsive contractions of the colorectum and that des-acyl ghrelin opposes this effect. At most other sites of ghrelin action, des-acyl ghrelin either has no effect or it mimics ghrelin. This is the first evidence that non-acylated ghrelin opposes the action of the acylated peptide in the spinal cord.

84 GENE EXPRESSION DURING BLASTOCYST-TO-ELONGATED STAGE IN BOVINE EMBRYOS DERIVED FROM SOMATIC CELL NUCLEAR TRANSFER

Epigenetic modification is an important factor in the development of embryos and the production of normal offspring derived from somatic cell nuclear transfer (NTSC). Several investigators have reported aberrant gene transcription in bovine NTSC embryos at the blastocyst (BC) stage. The objectives of this study were to evaluate the gene expression in NTSC embryos, which had developed to the elongated (EL) stage, and clarify differential levels of gene transcription in the embryo disc (ED) and trophectoderm (TE) of EL embryos. Five specific mRNAs [octamer-binding transcription factor (OCT-4), interferon-τ (IFN-τ), fibroblast growth factor receptor 2 (FGF-R2), and fibroblast growth factors 2 and 4 (FGF-2 and FGF-4)] were selected. Bovine BC embryos were obtained from NTSC using calf fibroblast cells or the uterus of donor cows after AI (Vivo). Some BC embryos were transferred to recipient cows at Day 7 (Day 0 = estrus), and then EL embryos were collected by uterine flushing at Day 16. Total RNA in single BC, ED, and TE were reverse-transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA was normalized to the abundance of GAPDH. A total of 15 (BC) and 7 (ED and TE) samples were used in each group to analyze the gene expression. Data on mRNA expression levels were analyzed using a Kruskal–Wallis test followed by multiple pair-wise comparisons using the Scheffe method. Most embryos (87–100%) gave positive signals of OCT-4, IFN-τ, and FGF-R2, regardless of the origin and stage of the embryos. Transcript signals of FGF-4 in BC embryos derived from Vivo (100%) and NTSC (70%) were detected with higher frequencies. At the EL stage, the FGF-4 signal was detected in only ED. The transcript of FGF-2 was detected with lower frequencies (20–27%) in BC embryos, but was consistently (71–86%) detected in ED of both groups. The relative abundance of OCT-4 expression in NTSC was higher (P &lt; 0.05) than in Vivo embryos at the BC stage. In contrast, the transcript of FGF-4 at the BC stage was lower (P &lt; 0.01) in NTSC than in Vivo embryos. Transcript levels of IFN-�, FGF-R2, and FGF-2 were not significantly different in both groups at the BC stage. The amount of OCT-4, FGF-4, and FGF-2 transcripts in ED were significantly (P &lt; 0.05) higher than in TE. Transcript levels of these genes did not differ between NTSC and Vivo embryos. FGF-R2 levels were not significantly different in origins and tissue of EL embryos. In Vivo embryos, the IFN-τ level of TE was significantly (P &lt; 0.05) higher than in ED. However, the difference in the IFN-τ transcription was not observed between ED and TE in NTSC embryos. The results of an analysis of mRNA transcripts at 2 different stages of development demonstrate that bovine NTSC embryos at the BC stage show deviations in expression patterns with respect to several genes which have important roles in cell differentiation, implantation, and embryo development, but these expressions, except for IFN-τ, were modified to a normal level according to the embryo development and differentiation.

42 PREPARTUM HORMONAL CHANGES IN RECIPIENT COWS FOR SOMATIC CELL CLONED FETUSES

Placental estrogens are associated with fetal growth and development, and play important roles in the initiation of the parturition process. In the delivery of somatic cell-cloned (SC) calves, recipient cows show a weak and unclear symptom of parturition, although large offspring syndrome (LOS) frequently occurs. The mortality of calves by dystocia decreases the efficiency of SC cattle production. In this study, we examined peripheral estrone (E1), estradiol-17� (E2), estrone sulfate (E1S), and progesterone (P4) levels during preparturition in recipients of SC and in vivo calves. Recipients were administered 20 mg dexamethasone (DEX) at Days 276-288 of pregnancy, followed by 0.75-1 mg cloprostenol (PG) and 20 mg estriol 24 h later. Calves (Japanese black cattle) were delivered 2 or 3 days after the DEX administration. SC calves were delivered by cesarean section (C-sec) when LOS was suspected by rectal palpation. Blood samples of recipients [vaginal delivery of SC (Vag): n = 13; C-sec of SC: n = 8; vaginal delivery of in vivo calves (Control): n = 4] were taken at Days 257 and 271 of pregnancy, and just before DEX (-2P), PG (-1P), and parturition (0P). Blood samples of calves were taken just after delivery to analyze cortisol level. The statistical significance was analyzed by the Steel-Dwass test. Birth weight of calves was the heaviest (P &lt; 0.05) in C-sec (62 � 3 kg; n = 12); Vag calves (43 � 2 kg; n = 19) were also heavier (P &lt; 0.05) than Control calves (29 � 2 kg; n = 9). E1 levels in Control calves remained low (&lt;629 � 111 pg mL-1) until Day 271 and then increased progressively (&gt;2156 � 599 pg mL-1). E1 levels tended to be lower in Vag (&lt;1968 � 299 pg mL-1) and C-sec (&lt;1268 � 385 pg mL-1) calves at -2P, -1P, and 0P; E1 levels in C-sec calves were significantly lower (P &lt; 0.05) than in Control calves at -2P (512 � 85 pg/mL-1) and -1P (725 � 91 pg mL-1). The E2 level in Control calves increased and reached a plateau at -2P. Vag and C-sec calves showed lower E2 levels, except that the Vag level at 0P was similar to that in Control calves. The E2 level of C-sec calves (61.8 � 25.3 pg mL-1) at 0P was significantly lower (P &lt; 0.05) than that of Control calves (247.5 � 102.8 pg mL-1). E1S levels in Vag and C-sec calves increased progressively from -2P to 0P, whereas the E1S level in Control calves increased at 0P. The E1S level in Vag calves (41.1 � 4.1 ng mL-1) was significantly higher (P &lt; 0.05) than in Control calves (19.4 � 5.1 ng mL-1) at -1P. P4 levels decreased from -2P in Vag and Control calves, and from -1P in C-sec calves. The cortisol level in C-sec calves (60.1 � 19.1 ng mL-1) tended to be low compared with that in Vag (104.4 � 23.1 ng mL-1) and Control (93.4 � 15.0 ng mL-1) calves. This study revealed fetoplacental dysfunction of estrogen synthesis in the SC fetus during preparturition. Elevated E1S levels in recipients of the SC fetus, which correlated with high birth weight and agreed with previous reports for normal or plural pregnancy, might cause the reduction of E1 level. The comparable level of cortisol in Vag and Control calves indicated that SC calves had normal adrenal cortex function. Further analysis on placental estrogen synthesis and cortisol secretion in the SC fetus is necessary to clarify the cause of the prolonged gestation.

167 EXPRESSION OF INTERFERON τ IN BOVINE EMBRYOS DERIVED FROM PARTHENOGENETIC ACTIVATION

Parthenogenetic activation (PA) is a useful technique for reproductive technologies such as somatic cell nuclear transfer. Furthermore, there is a possibility of embryonic stem cell establishment deriving from PA embryos (Cibelli et al. 2002 Science 295, 819). Understanding of the ability of development and differentiation in PA embryos is important for the application. This study was designed to assess the gene expression of octamer-binding transcription factor (OCT-4) and interferon τ (IFNτ) in bovine PA embryos at the blastocyst (BC) and elongated (EL) stages, and the protein secretion of IFNτ at the EL stage. PA embryos were produced from oocytes matured in vitro (24 h), activated with Ca-ionophore (5 min) and electric pulse, and then treated with cytochalasin B and cycloheximide (5 h). In vivo-produced (Vivo) embryos were obtained non-surgically at Day 8 (Day 0 = estrus) from superovulated donor cows. PA or Vivo embryos were transferred to recipient cows (PA: 10 embryos/cow; Vivo: 1 embryo/cow) at Day 8, and then recovered non-surgically with uterine flushings at Day 16. Total RNA in single BC and EL embryos were reverse transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA was normalized to the abundance of GAPDH. IFNτ secretion of uterine flushings was estimated by RIA (Takahashi et al. 2005 Theriogenology 63, 1050–1060). The cleavage and blastocyst developmental rates of PA oocytes were 65.8 and 29.7%, respectively. Most embryos had positive signals of OCT-4 and IFNτ regardless of the origin and stage of embryos. The relative abundance (mean � SEM) of OCT-4 expression in PA and Vivo embryos dropped to its lowest level (1.78 � 0.32 and 1.14 � 0.45, respectively) at the EL stage, and it was significantly lower than that at the BC stage (1018.87 � 148.69 and 696.29 � 151.80, respectively; P &lt; 0.05). The transcript level of OCT-4 was not significantly different between PA and Vivo embryos at both stages. Although the transcript level of IFNτ in PA and Vivo embryos increased significantly at the EL stage (0.36 � 0.06 and 7.68 � 2.01, respectively) from the BC stage (0.03 � 0.01 and 0.01 � 0.004, respectively; P &lt; 0.05), that in PA embryos was significantly lower than that in Vivo embryos at the EL stage (P &lt; 0.01). The total amount (mean � SEM) of IFNτ in uterine flushings from cows with transferred PA embryos was 3.38 � 0.35 �g (the number of embryos in each uterine flushing was unknown), and it was low compared with that from cows with Vivo embryos (13.40 � 3.03 �g). Our results indicate that bovine PA embryos have the ability to secrete IFNτ in the uteri of recipient cows at the EL stage, and there is a similar expression pattern of OCT-4 for Vivo embryos.

170 EXPRESSION PROFILE AND PROTEIN SECRETION OF BOVINE INTERFERON τ ON DAYS 12 TO 28 IN EARLY PREGNANCY

Bovine interferon (bIFN) τ has been implicated as a mediator of maternal recognition of pregnancy in cattle. Ovine (o) and bIFNτ expression show temporal patterns until implantation begins (Farin et al. 1990 Biol. Reprod. 43, 210–218); therefore, the expression peaks of bIFNτ are not well understood. This study aimed to investigate the expression profile of mRNA and protein secretion of bIFNτ in conceptuses obtained from cows on Days 12 to 28 in early pregnancy. Induction of superovulation and recipient synchronization were achieved by previously reported methods (Hirayama et al. 2004 Theriogenology 62, 887–896). Embryos were recovered non-surgically on Day 8 (Day 0 = estrus). Subsequently, recovered embryos were singly transferred to recipients immediately upon evaluation. Bovine conceptuses and uterine flushings were collected non-surgically from embryo-transferred cows on Days 12 (n = 2), 14 (n = 6), 16 (n = 5), 18 (n = 4), and 20 (n = 5) with MEM. On Days 22 (n = 3), 24 (n = 5), and 28 (n = 2), bovine conceptuses were recovered within 30 min after slaughter by flushing the uterus with PBS supplemented with 0.1% BSA. Uterine flushings were also collected from 6 cows in the control group on Day 16 of the estrous cycle. Conceptuses for collection of RNA were processed individually and stored at -80�C until analysis. The flushing was centrifuged at 1800g and 4�C for 30 min to remove cellular debris, and stored at -30�C for subsequent measurement of bIFNτ. Total RNA in conceptuses were reverse transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA concentration was normalized to the abundance of GAPDH. BIFNτ contents of the uterine flushings were measured by RIA (Takahashi et al. 2005 Theriogenology 63, 1050–1060). Intra-assay and inter-assay CVs were 11.0 and 8.5%, respectively. Transcripts of bIFNτ were detected in all samples from Days 12 to 28; the expression of mRNA increased remarkably from Day 16 (mean � SEM, 2.15 � 0.66) to Day 18 (9.62 � 4.09), and then declined on Day 20 (3.42 � 0.86). Protein detected on Day 16 was 13.3 � 3.02 �g. An increase of bIFNτ secretion was observed between Day 18 (39.8 � 20.62 �g) and Day 20 (71.9 � 17.36 �g); thereafter it decreased on Day 22 (27.2 � 2.83 �g). BIFNτ displayed a pattern of expression similar to that of oIFNτ, with mRNA expression peaking around Day 18 (ovine, Days 12/13) and protein secretion on Day 20 (ovine, Days 15/16), thereby reflecting the comparatively later time frame of maternal recognition of pregnancy in cattle. These results indicate that the expression and secretion profiles of bIFNτ show temporal and spatial patterns in early pregnancy.

204 RELATIONSHIP BETWEEN RESPIRATORY ACTIVITY AND THE PREGNANCY RATE OF BISECTED BOVINE EMBRYOS IN VIVO

Oxygen consumption is an important indicator of the metabolic activity of living cells, which may provide valuable information for evaluating embryo quality. We have found that the bovine embryos with high oxygen consumption possess stronger potential for further development. However, the relationship between respiratory activity and the pregnancy rate of embryos is still unclear. In this study, we investigated the respiration rates of bisected bovine embryos and the pregnancy rates of demi-embryos after embryo transfer. Compact morula-stage embryos were bisected evenly by micro glass needle. One hundred bisected embryos were incubated for 24 h in embryo culture medium (IVD101; Research Institute for the Functional Peptides, Yamagata, Japan) at 39�C under 5% CO2, 5% O2, 90% N2. After the incubation, demi-embryos were classified into 2 groups: blastocoel-formed (BC) and blastocoel-not-formed (CM) embryos. Oxygen consumption rates of demi-embryos were measured by scanning electrochemical microscopy (SECM; Hokuto Denko Corporation, Tokyo, Japan). Within 3 h after the measurement, 80 demi-embryos were transferred into recipient cows (one demi-embryo/one recipient) at 7–8 days after estrus. Recipient cows were diagnosed for pregnancy by ultrasonography approximately 40 days after estrus. Statistical difference was analyzed by Tukey's post-hoc test and chi-square test. A total of 27 recipient cows became pregnant; the pregnancy rates for cows with CM and BC demi-embryos were 40.6% (13/32) and 29.2% (14/48), respectively. Mean oxygen consumption rates (� 10-14 mol s-1) in pregnant and non-pregnant cows were 0.47 and 0.39 for CM demi-embryos and 0.63 and 0.52 for BC demi-embryos, respectively. Retrospective analysis showed that the respiratory activity of demi-embryos in the pregnant group was higher than those in the non-pregnant group. In particular, the pregnancy rates for demi-embryos with respiratory activity higher than 0.35 in CM and 0.40 in BC groups were 52.0% (13/25) and 35.9% (14/39), respectively. On the other hand, cows with demi-embryos having an oxygen consumption rate under 0.35 in CM (n = 7) and 0.40 in BC (n = 9) groups did not become pregnant. These results demonstrated that bovine demi-embryos with higher respiratory activity showed a high pregnancy rate after embryo transfer. It is generally known that the pregnancy rate after the transfer of bisected embryos is lower than that of whole embryos. The measurement of oxygen consumption by SECM procedures is a useful tool to assess the quality of pre-implantation embryos and may contribute to the improvement of the success rate for bisected embryo transfer.

Radiation safety design for the J-PARC Project

The High-Intensity Proton Accelerator Project, named J-PARC, is in progress, with the aim of enabling studies on the latest basic science and the advancement of nuclear technology. In the project, a high-energy proton accelerator complex with the world's highest instantaneous intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.

Arrangement of high-energy neutron irradiation field and shielding experiment using 4 m concrete at KENS

An irradiation field of high-energy neutrons produced in the forward direction from a thick tungsten target bombarded by 500 MeV protons was arranged at the KENS spallation neutron source facility. In this facility, shielding experiment was performed with an ordinary concrete shield of 4 m thickness assembled in the irradiation room, 2.5 m downstream from the target centre. Activation detectors of bismuth, aluminium, indium and gold were inserted into eight slots inside the shield and attenuations of neutron reaction rates were obtained by measurements of gamma-rays from the activation detectors. A MARS14 Monte Carlo simulation was also performed down to thermal energy, and comparisons between the calculations and measurements show agreements within a factor of 3. This neutron field is useful for studies of shielding, activation and radiation damage of materials for high-energy neutrons, and experimental data are useful to check the accuracies of the transmission and activation calculation codes.

Experimental determination of minimal stimulation current and period for electrical thrombosis in dogs

SUMMARY

Endovascular surgery has been proposed as an alternative treatment for cerebral aneurysms. However, for wide neck and large sized lesions it is very difficult to obtain complete occlusion and tissue organization. The present study was conducted to examine the efficacy of electrical thrombosis for cerebral aneurysms and parent arterial occlusions using Interlocking Detachable Coils (IDCs), focusing on the minimum current volume and stimulation time required for stable electrical thrombosis formation. We used ten mixed-breed adult dogs (in the study body weights 9-12 kg; males: 5, females: 5). Guiding catheter sand microcatheters were introduced into both sides of the distal external carotid artery (ECA) and placed at the same level. To prevent migration, IDCs (4 mm x 12 cm) were placed in the ECA without being detached. After confirming no vessel occlusion, we applied a positive current (2-6 mA) to the coil on one side and performed angiography every ten minutes to observe whether vessel occlusion with electrothrombosis had occurred. It was determined that to achieve complete occlusion of the external carotid arteries in mixedbreed dogs, a minimum stimulation current of 4mA and a minimum stimulation time of ten to 20 minutes are required.

The efficacy of coil embolization at the dissection site of ruptured dissecting vertebral aneurysms

SUMMARY

Proximal occlusion of the parent artery has been widely used for treatment of vertebral dissecting ruptured aneurysms, but this does not always completely prevent re-rupture. In this series, the efficacy of occlusion at the dissection site using detachable coils was compared with proximal balloon occlusion. Over a five year period, 25 patients suffering from subarachnoid hemorrhage with dissecting vertebral aneurysms were treated by endovascular surgery. The first three of these 25 patients were treated with proximal balloon occlusion of the parent artery. The remainder underwent platinum coil occlusion at the affected site as early as possible after the diagnosis. In two of the three cases treated with proximal balloon occlusion, clipping or coating surgery were added because of progressive dissection. In all 22 cases of coil embolization, the intervention was successfully performed without complication. In one case with a dissection involving bilateral vertebral arteries, minor rebleeding from a contralateral dissection occurred after embolization. In the other 21 cases, rebleeding was not apparent (clinical follow-up: mean 24 months). Radiological findings showed complete occlusion of the dissection site and patency of the non affected artery (follow-up: mean ten months). We conclude that detachable platinum coil embolization at the dissection site is more effective than proximal occlusion for treatment of ruptured vertebral dissecting aneurysms because of immediate cessation of blood flow to the dissection site. However, in cases with bilateral dissections or hypoplastic contralateral vertebral arteries, preceding bypass surgery or stent treatment to preserve the affected vertebral artery may be needed.

Response of GafChromic MD-55 radiochromic film to synchrotron radiation

Synchrotron radiation has been increasingly and extensively used for materials science, biology and medical research. For measurement of high dose from the low energy photons, tissue-equivalent dosemeters having linearity in the Gy region are required. In this study, energy and dose responses of double-layer Gafchromic film MD-55 were measured using 10-40 keV monoenergetic photons from synchrotron radiation. The result showed that the energy responses normalised at 60Co gamma rays were 0.58-0.59 at 10-20 keV, 0.66 at 30 keV and 0.72 at 40 keV in air. The linearity was confirmed to extend from 2 Gy to 100 Gy.

Evaluation of left ventricular function using electrocardiographically gated myocardial SPECT with (123)I-labeled fatty acid analog

Electrocardiographically (ECG) gated myocardial SPECT with (99m)Tc-tetrofosmin has been used widely to assess left ventricular (LV) function. However, the accuracy of variables using ECG gated myocardial SPECT with beta-methyl-p-(123)I-iodophenylpentadecanoic acid (BMIPP) has not been well defined.

METHODS

Thirty-six patients (29 men, 7 women; mean age, 61.6 +/- 15.6 y) with ischemic heart disease underwent ECG gated myocardial SPECT with (123)I-BMIPP and with (99m)Tc-tetrofosmin and left ventriculography (LVG) within 1 wk. LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), and LV end-systolic volume (LVESV) were determined on gated SPECT using commercially available software for automatic data analysis. These volume-related items on LVG were calculated with an area-length method and were estimated by 2 independent observers to evaluate interobserver validity. The regional wall motion with these methods was assessed visually.

RESULTS

LVEF was 41.1% +/- 12.5% on gated SPECT with (123)I-BMIPP, 44.5% +/- 13.1% on gated SPECT with (99m)Tc-tetrofosmin, and 46.0% +/- 12.7% on LVG. Global LV function and regional wall motion between both gated SPECT procedures had excellent correlation (LVEF, r = 0.943; LVEDV, r = 0.934; LVESV, r = 0.952; regional wall motion, kappa = 0.92). However, the correlations of global LV function and regional wall motion between each gated SPECT and LVG were significantly lower. Gated SPECT with (123)I-BMIPP showed the same interobserver validity as gated SPECT with (99m)Tc-tetrofosmin.

CONCLUSION

Gated SPECT with (123)I-BMIPP provides high accuracy with regard to LV function and is sufficiently applicable for use in clinical SPECT. This technique can simultaneously reveal myocardial fatty acid metabolism and LV function, which may be useful to evaluate various cardiac diseases.

Enhancing osseointegration by capacitively coupled electric field: a pilot study on early occlusal loading in the dog mandible

Expeditious postoperative appositional growth of bone to dental implants is desired for clinically successful fixation of oral implants. The present study was performed to evaluate the effect of applying a capacitively coupled electric field (CCEF) followed by functional loading on peri-implant osteogenesis in the dog mandible. Nine adult beagles were used in this study. All premolars on both sides of the mandible were removed from each dog. A physio-odontlam implant (POI, Ti-6AI-4v) with 2 stages (3.7 mm in diameter and 8.0 mm in length), whose surface had been treated with anodic oxidation and sandblasted, was placed into each test site by self-tapping. Daily application of CCEF (8 hours per day) was initiated on the day following surgery and continued for 14 days or 21 days. After CCEF treatment was finished for each period, a prosthetic abutment and a straight post were placed on each implant. Four days after placement of the post, implants were placed under functional loading for 30 days. The dogs were then sacrificed, and histologic and radiographic studies of the mandible were performed. Relatively well calcified, mature bone with a lamellar-like structure was observed by contact microradiography and histologic study (double staining with basic fuchsin-methylene blue) of the peri-implant region on the CCEF-treated samples. In contrast, poorly calcified, immature bone without a lamellar structure was observed in control sites not treated with CCEF. The bone area ratios of the CCEF-treated sides were larger than those of control sides. These results suggest that the application of CCEF after implant placement may enhance peri-implant osteogenesis, even with functional loading.

Traumatic basilar artery occlusion caused by a fracture of the clivus--case report

A 56-year-old man presented with a rare traumatic basilar artery occlusion caused by a fracture of the clivus. He fell from the height of 2 meters and immediately fell into a coma. Head computed tomography (CT) revealed an open depressed fracture, an acute epidural hematoma 1 cm thick in the left middle frontal fossa, and a longitudinal fracture of the clivus. Emergency removal of the hematoma was performed with cranioplasty. Head CT 8 hours 50 minutes after injury showed infarctions in the brain stem, cerebellum, and occipital lobes. Cerebral angiography revealed occlusion of the basilar artery in the middle part of the clivus. The patient died after 3 days. Autopsy revealed that the basilar artery was trapped in the clivus fracture site. Vertebrobasilar artery occlusion due to trapping in a clivus fracture has a very poor prognosis. Diagnosis is difficult and generally only confirmed at autopsy. Cerebral angiography is recommended in a patient in a deep coma without massive brain contusion at the early stage of head injury to identify the possibility of vertebrobasilar artery occlusion in a clivus fracture.

An experimental study on radiation streaming through a labyrinth in a proton accelerator facility of intermediate energy

A radiation streaming experiment has been carried out at the Takasaki Ion Accelerator Facility for Advanced Radiation Application at the Japan Atomic Energy Research Institute in a room housing a Cu target irradiated with 68 MeV protons and in a labyrinth of three-legs having a total length of 29 m. In the experiment, neutron and gamma ray energy spectra, neutron reaction rates, and neutron and gamma ray dose equivalent rates were measured using various counters and dosimeters. The experimental data show the applicability of some empirical formulas for estimating the thermal neutron flux in a room and neutrons streaming in a labyrinth designed for a proton accelerator operating in the intermediate energy region. The data suggest that it is mandatory to estimate the gamma ray dose equivalent rate in a labyrinth, which is dominated by the secondary gamma rays due to the neutron capture reaction.

Histopathologic evaluation of coronary artery thrombi obtained by directional coronary atherectomy in patients with restenosis-induced unstable angina pectoris

The pathogenesis of unstable angina pectoris (UAP) following percutaneous transluminal coronary angioplasty (PTCA) or directional coronary atherectomy (DCA) has not been adequately investigated, so the present study aimed to determine whether thrombi are present in restenotic lesions. The study group comprised 14 patients (16 arterial branches) with angina pectoris in whom either PTCA or DCA was performed and who had developed UAP associated with restenosis, and who then underwent DCA of the restenosed lesion (R-UAP group). The control groups comprised individuals with UAP undergoing DCA with no prior history of PTCA or DCA (P-UAP group; n=29, 29 branches), patients with acute myocardial infarction (AMI group; n=34, 34 branches), and patients with stable angina pectoris (SAP group; n=31, 33 branches). The presence of thrombi was determined by light microscopy of histologic specimens. Thrombus was present in only 1 of the 16 (6.3%) branches in the R-UAP group. 21 of the 29 (72.4%) branches in the P-UAP group, and in 25 of the 34 (73.5%) in the AMI group. In the SAP group, it was detected in only 2 of the 33 (7.1%) branches. The incidence of thrombus was significantly lower in the R-UAP group than in the P-UAP group. In conclusion, the role of thrombus is limited in causing post-interventional UAP at restenosed sites.

[Usefulness of intravenous myocardial contrast echocardiography in rats]

OBJECTIVES

Few intravenous myocardial contrast echocardiography trials have evaluated myocardial perfusion in small animals. The feasibility of using intravenous myocardial contrast echocardiography to assess the ischemic area in rats was investigated.

METHODS

Fourteen open chest Wister male rats were examined. Intravenous myocardial contrast echocardiography was performed by fundamental and intermittent mode using a high frequency (5-12 MHz) transducer (SONOS 5500) with injection of NC100100 (20% dilution) into the femoral vein. The mechanical index was set to 1.6. Baseline-subtracted video intensity (256 level) was measured in the anterior, posterior, septal and lateral walls of the left ventricle. The left anterior descending artery was ligated in 16 rats. The area at risk was evaluated by myocardial contrast echocardiography and compared to the area of defect by Evans Blue staining.

RESULTS

All wall segments were clearly opacified (anterior 63.8 +/- 24.7, posterior 27.0 +/- 11.0, septal 44.5 +/- 11.6, lateral 52.3 +/- 19.1), although the baseline-subtracted video intensity of the posterior wall was low. The area at risk was clearly observed, and there was a good correlation with the nonperfused area by Evans Blue staining (y = 1.13x-3.54, r = 0.98).

CONCLUSIONS

Intravenous myocardial contrast echocardiography can detect the perfusion defect even in rats using a high frequency transducer and suitable setup of equipment.

Dose measurements in inhomogeneous bone/tissue and lung/tissue phantoms for angiography using synchrotron radiation

For angiography using synchrotron radiation we measured the absorbed dose distribution in inhomogeneous phantoms with thin LiF:Mg, Cu, P, LiF:Mg, Ti thermoluminescent dosimeters (TLDs) in tissue and lung substitutes, and with Mg2SiO4:Tb TLDs in bone substitute for 33.32 keV monoenergetic photons from synchrotron radiation. The energy responses of the TLDs were measured in air for 10-40 keV monoenergetic photons. The values at 30 keV became smaller by 30% for LiF:Mg, Cu, P and larger by 22% for Mg2SiO4:Tb than the ratio of the mass energy absorption coefficients of the TLDs to that of air. These values were used to modify the calculated response of the TLDs in each phantom material. The absorbed dose distribution obtained was compared with that calculated using the Monte Carlo transport code EGS4 expanded to a low-energy region, and their agreement was confirmed taking linear polarization into account. In the bone substitute the dose increased by a factor of 3.9, while behind the bone the dose decreased drastically because of photon attenuation. In the lung substitute a slight dose difference from that in soft tissue was observed because of its different density. The LiF:Mg, Cu, P TLDs exhibited a better energy response, higher sensitivity and wider linear regions than did the other tissue-equivalent TLDs in the low-energy region.

Troglitazone, an antidiabetic drug, improves left ventricular mass and diastolic function in normotensive diabetic patients

AIMS

Patients with NIDDM have excessive cardiovascular morbidity and mortality, even in the absence of hypertension. Left ventricular hypertrophy (LVH), which is an ominous prognostic sign and an independent risk factor for cardiac events, is often present in NIDDM patients.

METHODS AND RESULTS

NIDDM male patients with (n=10) and without (n=12) hypertension, all of whom had been diagnosed over 10 years ago, were examined in the present study. Normotensive NIDDM patients had not received any anti-hypertensive drugs. All patients were classified according to the left ventricular mass (LVM) index by using M-mode echocardiography and were assessed regarding their systolic (fractional shortening) and diastolic function, which included the maximal early flow velocity (MFV), the mitral valve deceleration time (DT), and the isovolumic relaxation time (IRT) as determined by Doppler indices. Troglitazone (TRO), an antidiabetic drug, was administered to both groups at a dose of 400 mg/day for 6 months. After TRO treatment, a reduction in the LVM index and an improvement in the diastolic function were observed in the normotensive but not in the hypertensive patients.

CONCLUSION

The TRO treatment was sensitive for cardiac regression in those normotensive patients. These results suggest that LVH and the diastolic function in NIDDM patients without hypertension may be associated with elevated insulin resistance because TRO has a pharmacological function to increase the insulin sensitivity and to decrease insulin resistance.

Comparison of in-phantom dose distributions for coronary angiography using an x-ray machine and synchrotron radiation

Coronary cineangiography using synchrotron radiation is anticipated, owing to the high intensity and availability of monoenergy. To investigate allowable dose levels in clinical application, absorbed dose distribution in a tissue substitute phantom for a conventional x-ray machine was measured with thermoluminescent dosimeters at the University of Tsukuba under the practical conditions used for digital angiography. The dose rate at a 0.5-cm depth was 0.145 Gy/s, and the dose per frame was 0.725 mGy for the irradiation period of 5 ms per frame. For synchrotron radiation, the dose distribution measurement was made at a 5-GeV AR (Accumulation Ring) of the High Energy Accelerator Research Organization, in which a polymethylmethacrylate (PMMA) phantom was irradiated with the strongest beam available at the facility, which was 33.32 keV, 5.2 x 6.2 cm2 beam. Using this beam, a 1-mm-diameter coronary artery has been visualized at 1% iodine concentration at the AR. Nonhomogeneous strength distribution in the beam was observed in the vertical direction. The maximum dose rate was 0.556 Gy/s, and it attenuated to 1/3000 at a 30-cm depth in the beam center. At the deep positions, the doses were influenced by the high harmonics, which was confirmed with an EGS4 Monte Carlo calculation. Outside the beam, beam contamination on both sides of the main beam affected the doses. For comparison to the x-ray machine, the measured dose was analytically converted to that needed for a 5.2 x 16 cm2 beam that is used for clinical application. The dose rate at 0.5-cm depth was found to be 0.215 Gy/s, which is 1.48 times larger than that for x-rays. Moreover, the attenuation rate in the phantom was significantly greater than that of the x-ray machine, because of the difference of the energy spectra between the x-rays and synchrotron radiation used.

Arterial remodeling influences the development of intimal hyperplasia after stent implantation

OBJECTIVES

We examined whether preinterventional arterial remodeling influenced the interventional results after stenting.

BACKGROUND

Arterial remodeling is seen in atherosclerotic lesions, and it may play an important role in the early stage of atherosclerosis.

METHODS

We examined 113 lesions that underwent elective stenting using tubular slotted stents under intravascular ultrasound guidance. The lesions were divided into three groups--adequate, intermediate and inadequate remodeling group--according to preinterventional arterial remodeling. The patients were subjected to coronary angiography and intravascular ultrasound evaluation on average 6.4 months after stenting.

RESULTS

At baseline and immediately after stenting, there were no differences in quantitative angiographic analysis among remodeling groups. However, the plaque cross-sectional area (CSA) in the minimal lumen CSA at preintervention and intimal hyperplasia CSA at follow-up were significantly larger in the adequate remodeling group than in the inadequate remodeling group. The restenosis rate of stenting for the lesions with inadequate arterial remodeling was very low (9.4%). A significant positive correlation was found between preinterventional plaque CSA and intimal hyperplasia CSA at follow-up (r = 0.47, p < 0.0001). Moreover, remodeling index significantly correlated with relative intimal hyperplasia CSA (r = 0.28, p < 0.01).

CONCLUSIONS

Preinterventional arterial remodeling influenced the development of intimal hyperplasia after stenting.

Determination of left ventricular mass by echocardiography in normotensive diabetic patients

Patients with Type 2 diabetes mellitus (DM) have excessive cardiovascular morbidity and mortality, even in the absence of hypertension. Left ventricular hypertrophy (LVH), which is an ominous prognostic sign and an independent risk factor for cardiac events, is often present in Type 2 DM patients. Forty-two Type 2 DM patients without hypertension, all of whom had been diagnosed more than 10 years ago, were examined in the present study. They had no evidence of renal dysfunction and had not received any anti-hypertensive drugs. Age-matched healthy normal subjects (n=47) were recruited as controls. All participants were classified according to the left ventricular mass index (LVMI) using M-mode echocardiography and their systolic function (fractional shortening) was examined. The systolic function was not significantly different between the Type 2 DM and control groups. LVH can be seen even in the normotensive Type 2 DM patients, with these patients still having a higher LVMI than the normal control subjects. Although the plasma insulin levels were not significantly increased in the Type 2 DM patients, the LVMI significantly correlated with plasma insulin levels. However, the LVMI did not significantly correlate with plasma fasting glucose and hemoglobin A1c in the Type 2 DM patients. These results suggest that LVH in Type 2 DM patients without hypertension may be associated with elevated plasma insulin levels.

Crystal structures of heptakis(2,6-di-O-ethyl)cyclomaltoheptaose

Heptakis(2,6-di-O-ethyl)-beta-cyclodextrin (DE-beta-CD) was crystallized in two forms from hexane and 95% aqueous methanol, respectively: A form I crystal with the space group P2(1)2(1)2(1) and a form II crystal with the space group P3(1). In both crystals, DE-beta-CD molecules are in a round shape with intramolecular O-3-H...O-2 hydrogen bonds. In the form I crystal, the DE-beta-CD molecules are arranged along the twofold screw axis to form a helically extended polymeric chain by including the 6-O-ethyl groups of the adjacent molecule. One hexane molecule with twofold disorder is located in the intermolecular channel along the a-axis. In contrast, the DE-beta-CD molecules in the form II crystal form a helical arrangement along the threefold screw axis. One methanol and one water molecule are included on the O-6 side of the molecular cavity. The water molecule links the methanol molecule and two ethoxy groups of the adjacent DE-beta-CD molecule with hydrogen bonds. The result suggests the important role of solvent in the formation of helical arrangement of DE-beta-CD molecules.

Novel toluene elimination system in a toluene-tolerant microorganism

In studies of Pseudomonas putida IH-2000, a toluene-tolerant microorganism, membrane vesicles (MVs) were found to be released from the outer membrane when toluene was added to the culture. These MVs were found to be composed of phospholipids, lipopolysaccharides (LPS), and very low amounts of outer membrane proteins. The MVs also contained a higher concentration of toluene molecules (0.172 +/- 0. 012 mol/mol of lipid) than that found in the cell membrane. In contrast to the wild-type strain, the toluene-sensitive mutant strain 32, which differs from the parent strain in LPS and outer membrane proteins, did not release MVs from the outer membrane. The toluene molecules adhering to the outer membrane are eliminated by the shedding of MVs, and this system appears to serve as an important part of the toluene tolerance system of IH-2000.

A mathematical method for investigating dynamic behavior of an idiotype network of the immune system. The time minimum optimal control theory

We proposed a mathematical method to investigate an integrated property of an idiotype immune network under the time minimum optimal control. The transient changes of amounts of B cell receptor bound antibodies and immune complex in the network system were expressed by detailed differential equations. The rate constant for binding the second Fab arm of antibody was set as a function of coulombic repulsive force to express the influence of redistribution of electrical charges in the ligand-receptor molecular complex. We proposed time minimum optimal control strategy as an organizing principle for rapid reactions of the immune system. Based on the rigorous mathematical foundations of the optimal control theory, we determined the differential equations for co-state variables for the state variables to compute the time minimum transient changes in the amount of the species. Biological parameters in the immune reactions were utilized from the reported experimental data. Numerical computation disclosed that influence of changes in a rate constant extended to all the species of the network. Changes in a rate constant in a different B cell system reinforced the collaborations among the idiotypes and lead them to set in motion the ejection of the antigen. Simulation of reported experimental data by the present method was successful. There were, however, some inevitable dissociations between reported experimental data and computed results. The present method will be available for evaluating the time minimum reaction of the immune network system.

Cement failure loads of 4 provisional luting agents used for the cementation of implant-supported fixed partial dentures

The major disadvantage of cement-retained implant-supported fixed partial dentures (FPDs) is difficulty in retrievability. The retentive strengths of the provisional luting agents usually employed in these cases are therefore an important consideration. This study evaluated the cement failure loads of 4 provisional luting agents used for the cementation of FPDs supported by 2 implants or 4 implants. Nogenol luting agent exhibited the lowest retentive values in both types of FPD. ImProv proved to be the most retentive cement of all tested. Temp Bond NE and Temp Bond presented significantly different values (P < .05) for the 2-implant FPD, but not for the 4-implant model. On the basis of the study results, it may be concluded that Nogenol appears to be more appropriate for cementation of both 2- and 4-implant-supported FPDs when removal of the provisionally cemented superstructure is anticipated.