Dynamics of Double Bubble Tabular Film Process for Producing Biaxially oriented Nylon 6 Film

A double bubble tubular film process for nylon 6 was investigated. This report discussed three topics: Relationship between process conditions and film stretching stresses; deformation rate during double bubble process, birefringence and film thickness uniformity; and scale-up rule for double bubble tubular film process. The optimum stretching stress during the double bubble tubular film process exists. The bubble break occurs over stress of 1300 Kg/cm2 and bubble stability occurs below stress of 600 Kg/cm2. The cross point of stretching stress, which means stress in the machine direction is equal to stress in the transverse direction, is influenced by a deformation rate which is closely related to birefringence and bubble stability. Bubble stability and film thickness uniformity are improved with increasing deformation rate. It is found that the scale-up rule which was set up theoretically is applicable to predict the physical properties and bubble stability for large scale double bubble tubular film process once the same process is carried out by using the same scale machine and a small amount of resin.

Prediction of Birefringence for Optical Memory Disk

Polycarbonate (PC) is considered to be a proper resin for optical memory disk, however PC resin shows high birefringence. It is very important to reduce birefringence of PC optical memory disk. This research is to obtain the relationship between birefringence and process conditions and to get the optimum condition for the production of low birefringence substrate of PC optical memory disk. The birefringence distribution of PC optical memory disk was theoretically predicted by the calculations of both the stress distribution caused by molecular orientation during the filling stage and the thermal stress caused by temperature difference during the cooling stage. The relationship between birefringence distribution and the process conditions such as rheological properties of PC resin, injection temperature, mold temperature, mold design and annealing condition is possible to be predicted theoretically by calculating shear stress during the injection process and thermal stress during the cooling process. The predicted results of birefringence distribution qualitatively agree with the experimental ones.

Differentiating the roles of STAT5B and STAT5A in human CD4+ T cells

STAT5A and STAT5B are highly homologous proteins whose distinctive roles in human immunity remain unclear. However, STAT5A sufficiency cannot compensate for STAT5B defects, and human STAT5B deficiency, a rare autosomal recessive primary immunodeficiency, is characterized by chronic lung disease, growth failure and autoimmunity associated with regulatory T cell (Treg) reduction. We therefore hypothesized that STAT5A and STAT5B play unique roles in CD4(+) T cells. Upon knocking down STAT5A or STAT5B in human primary T cells, we found differentially regulated expression of FOXP3 and IL-2R in STAT5B knockdown T cells and down-regulated Bcl-X only in STAT5A knockdown T cells. Functional ex vivo studies in homozygous STAT5B-deficient patients showed reduced FOXP3 expression with impaired regulatory function of STAT5B-null Treg cells, also of increased memory phenotype. These results indicate that STAT5B and STAT5A act partly as non-redundant transcription factors and that STAT5B is more critical for Treg maintenance and function in humans.

Thickness Uniformity of Double Bubble Tubular Film Process for Producing Biaxially Oriented PA 6 Film

It is known that while the double bubble tubular film process gives better impact strength and more uniform shrinkage balance than the tenter process, yet it is relatively poor in film thickness uniformity. The film thickness uniformity of the PA 6 produced by the double bubble tubular film process was investigated.

The optimum stretching stress during the double bubble tubular film process exists. The bubble breaks over stress 130 MPa and bubble is unstable below stress 60 MPa. In the optimum condition, which is process temperature 310 °C and stretching ratio 3.2, stretched film uniformity was twice worse than non-stretched film one. The thickness uniformity of the film stretched in the optimum condition was better than that of the film stretched at higher process temperature and at lower stretching ratio. In the observations of the bubble sample through the polarizing plates, deformation pattern showed the equality of deformation. Thickness uniformity of non-stretched film significantly affects the thickness uniformity of biaxially oriented film.

Local stretching ratio, which varies along the film width, influences tensile modulus and tensile strength at break. In order to obtain the uniform physical properties of film, it is important to produce the film with uniform thickness. Film thickness uniformity can be improved when stretching stress is high and bubble stability is good. These factors are influenced by stretching temperature, stretching ratio and air velocity from air ring.

Deformation Behavior, Processability and Physical Properties for Biaxially Oriented Film of LLDPE

The bubble deformation behavior of double bubble tubular film (DBTF) of linear low density polyethylene (LLDPE) is experimentally analyzed. Also investigated is how the bubble deformation behavior of the stretched films are changed by stretching conditions, especially stretching temperature, and how the properties of stretched films are influenced by stretching conditions.

From the results, the optimum conditions required to obtain a stable bubble and good properties for the DBTF of LLDPE are indicated. The relationship between the DBTF and laboratory tenter stretched film (LTSF) is investigated in order to predict the processability and the properties of the DBTF by using the laboratory tenter biaxial stretcher. This method is not only more time efficient, but also reduces overall costs of developing the DBTF.

Easy Tear Film of Biaxially Oriented PA 6/MXD 6 Blend by Double Bubble Tubular Film Process

In the market, a film which adapted to environmental and barrier problems is desired. This report discusses the stretching stability and physical properties for biaxially oriented PA 6/ MXD 6 blending film produced by double bubble tubular film process. As MXD 6 blending ratio increased, the stretching stress decreased. Hydrogen bond is due to be suppressed by the steric hindrance of the MXD 6 resin. Blending film can be stretched stably and oxygen gas permeability is more excellent than PA 6. Further the film blended between 20 % and 40 % as MXD 6 blend ratio has the property of easy straight line cut. It is found that the plate-like cylinder structure was formed in the observation of TEM. However, thickness uniformity deteriorates when MXD 6 blending ratio exceeds 40 %. To improve the thickness uniformity, the influence of the kneading conditions was studied. When the melting point of MXD 6 decreased, the stretching stability deteriorated and mechanical properties drastically lowered. The excess reaction of the blending resins is not desirable. Stretchability, easy tear property and oxygen gas barrier property are maintained by following process conditions. In case of dry blending, MXD 6 30% is proper content. And in case of premixing, MXD 6 melting point keeps over 236°C. It was confirmed that there is the condition satisfying all properties. The blending film keeps the compatible performance of strength and easy tear property. Namely, the material and production technology of a film could solve environmental and barrier free problems.

Bowing Phenomenon in Double Bubble Tubular Film Processing for PA 6

This report is to discuss the bowing phenomenon and the sag elimination tension for biaxial oriented PA 6 film process, which consists of double bubble tubular film process and the thermosetting tentering.

The bowing phenomenon does not occur in the heat set of the triple bubble tubular process. However, there is a serious problem of the bubble stability when the sufficient thermosetting by the tubular process is carried out, so the heat set by the tenter process is required. The bowing phenomenon arises when the annealing is carried out by the tenter method. The bowing distortion becomes large when the annealing temperature is high and film relaxation ratio is large.

It is possible to reduce the bowing distortion when thermosetting is carried out in a two-step tenter process. The shrinkage stress of the stretched film was relaxed in the heat treatment during the second step whose temperature is higher than the first one. A two-step heat treatment was able to decrease the bowing distortion compared with the one-step heat treatment.

When the bowing phenomenon occurred, shrinkage percentage in hot water changes along the cross-direction of a film. The humidity expansion coefficient in the film which increases as the increasing shrinkage percentage in hot water is related to the molecular orientation. The sag also increased with increasing the bowing distortion. The bowing distortion and the sag elimination of tension have proportional connection.

Stretchability and Properties of LLDPE Blends for Biaxially Oriented Film

In order to improve the stretchability of linear low density polyethylene (LLDPE) for double bubble tubular film (DBTF), the blending of LLDPEs have been investigated. Three LLDPEs of varying densities were blended, and several films having different densities, molecular-weight distributions and composition distributions were produced. The stretchability and properties of these films were investigated and the relationship between the stretchability and the material properties were also discussed. The material properties of LLDPE which showed better stretchability were reported. Furthermore, the stretchability of LLDPE by using the laboratory tenter stretched film (LTSF) and the DBTF were compared. The prediction of the stretchability for the DBTF by using the LTSF was reported.

Stretchability and Properties of Various LLDPE for Biaxially Oriented Film

Stretchability and properties of linear low density polyethylene (LLDPE) blends for biaxially oriented film was investigated in the previous report [1]. That report focused on changing the film density by blending three different densities of LLDPE. The relationship among stretchability, film density and the composition distribution was explored. In this report, several different densities and melt flow indices (MFI) of LLDPE were examined. A film with a density of about 0.915 g/cm3 displayed the best stretchability, while films not less than 2 g/10 min MFI had poor stretchability. The most suitable composition distribution for stretching was reported. The properties of biaxially oriented films were also evaluated. Furthermore, the relationship between the laboratory tenter stretched film (LTSF) and the double bubble tubular film (DBTF) was investigated. There was a correlation between the density in film over 0.910 g/cm3 and the stretchability of the DBTF and LTSF.

Easy Tear Multilayer Film of Biaxially Oriented PA6/MXD6 by Double Bubble Tubular Film Process

In the market, a film which is adapted to environmental and barrier problems and easy tear property is desired. A previous report discussed easy tear PA6 film. This report discusses the film having not only easy tear, but also high barrier properties.

A biaxially oriented PA6/MXD6 blend film produced by double bubble tubular film process does possess gas barrier. So a multilayer film having high gas barrier layer and keeping easy tear cut has been studied. High gas barrier layer of high content MXD 6 in the center layer is added to PA6/MXD6 blend film in the outer layers.

When MXD6 blending ratio of PA6/MXD6 blending film layer is 30 %, the property of easy straight line cut is obtained. It is found that the plate-like cylinder structure was formed in the observation of TEM for PA6/MXD6 blend film.

The multilayer biaxially oriented film composed of PA6/MXD6 blend layer and MXD6 high content layer keeps high strength, easy tear property and high gas barrier. Namely, the material and production technology of a PA6 film could solve environmental and barrier problems.

Study on the Bleeding Mechanism of Slip Agents in a Polypropylene Film using Molecular Dynamics

The bleeding (internal transport) process of additives in a polypropylene film under atmospheric pressure was investigated. The experimental results were explained more precisely by a new model assuming the two-step transport between the amorphous and crystalline regions. The diffusion coefficient of a higher fatty acid such as behenic acid (docosanoic acid) in isotactic polypropylene film and that of higher fatty acid amides such as erucamaide (13-cis-docosenamide) in ethylene copolymerized polypropylene film were determined at 40 and 50°C respectively. The difference between the diffusion coefficients of three slip agents in a polypropylene film at 50°C was explained using a molecular dynamics simulation in which self-association of the slip agent molecules by hydrogen bonding was considered.

Multilayer Barrier Film of Biaxially Oriented PA6/EVOH by Double Bubble Tubular Film Process

In the market, a film adapted to environmental and barrier problems is desired. The previous report discussed easy tear and gas barrier PA6 film. This report discusses the multilayer PA6 film having high barrier EVOH layer.

A biaxially oriented PA6 film produced by double bubble tubular film process has high strength, but does not have enough gas barrier property compared with K-coated PA6. In the following a multilayer film with gas barrier layer is studied. A high gas barrier layer of EVOH is added to the center layer in the outer layers of PA6 films. The gas barrier ability increases with increasing the content of EVOH and decreasing ethylene content of EVOH, but at the same time the mechanical properties and processability get worse. From this point of view, it is found that the optimum content of EVOH is between 20% and 43%.

In a biaxially oriented multilayer film composed of PA6 layers and EVOH one keeps high strength and high gas barrier. The material and production technology of a PA6 film can solve environmental and barrier problems.

Visualization of Flow Instabilities for High Density Polyethylene

Two typical flow instabilities of “Shark Skin” and “Melt Fracture” for high density polyethylene were investigated in this report. Experimental measurements were carried out methodically in a wide flow region from the reservoir (entry region) to the die land with a specific slit die. Especially the flow pattern was visualized with a high speed camera and the frequency of the flow instability was analyzed. Corresponding to the visualization analysis, the pressure fluctuation in the slit die and the surface roughness at the die exit were measured simultaneously and these frequency characteristics were analyzed with a FFT (Fast Fourier Transform) analyzer. As for “Shark Skin” region, the irregularity of the surface roughness in the broad frequency band was recognized at the die exit. In spite of this surface roughness, the pressure fluctuation and the fluctuation of the flow pattern at the wall vicinity in the die land were not observed. These results indicate that “Shark Skin” occurs at the die exit. As for “Melt Fracture” region, the periodical oscillation of the flow pattern and the periodical pressure fluctuation which corresponded to the periodical distortion of the extrudate was recognized in the die land. However the periodical oscillation of the flow pattern and the periodical pressure fluctuation could not be recognized in the reservoir (entry region of the die land). These results indicate that “Melt Fracture” is initiated at the die entry and occurs in the die land. Consequently it is clarified that “Shark Skin” occurs at the die exit and the flow instability which lead to “Melt Fracture” is initiated at the die entry and occurs in the die land.

Quantitative Analysis for Polymer Degradation in the Extrusion Process

Polymer degradation in the extrusion process decreases quality and productivity. For this reason, it is necessary to prevent polymer degradation. In the extrusion process, polymer degradation is caused by oxidation. It depends on the processing temperature and the amount of dissolved oxygen in the molten polymer. Therefore, a quantitative analysis of these factors is required.

As for the degradation characteristics of the material used in this study, temperature and oxygen concentration dependency of the oxidation rate could be quantitatively characterized with an apparatus to evaluate polymer degradation which utilized chemiluminescence generated by an oxidation reaction.

Moreover, an online measuring apparatus to analyze dissolved gas in the extruded molten polymer was developed. With this apparatus, the volume ratio of dissolved gases (N2, O2 etc.) to the extruded molten polymer could be quantitatively analyzed and the quality of the extruded molten polymer evaluated.

With this apparatus, dissolved nitrogen (an index of entrained air) was analyzed with a full-flight screw and a barrier screw. Furthermore, observation of cross sectional views in the screw channel obtained from the cooling experiment under the operating conditions was carried out for the full-flight screw and the barrier screw. With the full-flight screw, break up phenomenon (collapse of solid polymer) occurred in the screw channel and the amount of nitrogen increased. With the barrier screw, the amount of nitrogen decreased because of prevention of the break up phenomenon in the screw channel.

Consequently, it is shown that the use of the barrier screw is suitable for oxygen reduction in the molten polymer, which is a factor in causing polymer degradation.

297 PRODUCTION OF CHIMERIC PORCINE FETUSES BY AGGREGATION METHOD USING PARTHENOGENETIC EMBRYOS

Porcine induced pluripotent stem (iPS) cells are considered to be an invaluable research tool in translational research with pigs as a large animal model. Pluripotency of the iPS cells needs to be verified by their competence to contribute to chimera formation. The aim of the present study is to establish feasible system to create chimeric pig fetuses using parthenogenetic embryos. In Experiment 1, inner cell mass (ICM) was isolated by immunosurgery from Day 6 blastocysts obtained by parthenogenetic activation of in vitro matured (IVM) oocytes. Isolated ICM were used as the donor cells after staining with fluorescent carbocyanine dye (DiI). Using parthenogenetic morulae or 4- to 8-cell embryos as the host embryos, chimeric embryos were prepared by injection or aggregation method. Injection of ICM was performed by micromanipulation: a single ICM was directly injected into the centre portion of the host morulae. In the aggregation method, a single ICM was aggregated with blastomeres isolated from 2 host embryos at the morula or 4- to 8-cell stage in a micro-well (400 µm diameter, 300 µm deep). The chimeric embryos were cultured in PZM-5 (Yoshioka et al. 2008) for 2 to 3 days to examine development to blastocysts and incorporation of donor ICM cells into the resultant blastocysts ICM (ICM chimerism). In Experiment 2, donor blastomeres isolated from a parthenogenetic morula or 4- to 8-cell embryo were stained by DiI and aggregated with a parthenogenetic host embryo at the morula or 4- to 8-cell stage, and the in vitro development to the blastocyst stage and the ICM chimerism were examined. In Experiment 3, ICM isolated from IVF blastocysts harboring humanized Kusabira-Orange (huKO) gene were used as donor cells. Donor ICM were aggregated with the host embryos at the morula or 4- to 8-cell stage, and the resultant blastocysts were transferred to 4 recipient gilts to collect fetuses on Day 18. Results of Experiments 1 and 2 are summarised in Table 1. Combination of the donor ICM and host morulae yielded high rates of blastocyst formation (~95%) and ICM chimerism (~85%), regardless of the method used (injection or aggregation). Transfer of 73 blastocysts developed from host morulae to 2 recipients (Experiment 3) gave rise to 25 (34.2%) fetuses, of which 6 (24.0%) were confirmed to be chimeric by their clear orange fluorescence and immunostaining by anti-huKO antibody. Of 22 (40.7%) fetuses obtained after transfer of 54 blastocysts derived from 4- to 8-cell host embryos to 2 recipients, 3 (13.6%) were chimeric. Contribution of the donor cells in the tissues of the chimeric fetuses measured by image analysis software (ImageJ, NIH, Bethesda, MD, USA) ranged between 16.1 and 65.2%. These results demonstrate that the aggregation method using parthenogenetic host embryos is an efficient means to produce chimeric pig fetuses, and thereby feasible for verification of pluripotent cells such as iPS cells. Table 1.In vitro development of injected or aggregated porcine embryos

324 PRODUCTION OF GENETICALLY MODIFIED PIGS BY ARTIFICIAL REPRODUCTIVE TECHNOLOGIES USING FROZEN EPIDIDYMAL SPERM

Genetically modified (GM) pigs are useful tools for many types of biomedical research. The objective of this study was to develop a reliable protocol for the reproduction of GM pigs using frozen epididymal sperm. Epididymal sperm were collected from 3 GM boars: (1) humanized Kusabira-Orange (huKO) transgenic, (2) mutant human hepatocyte nuclear factor 1α (HNF-1α) transgenic, and (3) α1,3-galactosyltransferase gene knockout (GalT-KO). Additionally, a wild type (WT) boar was also used for sperm collection. After collection, the sperm were frozen in Niwa and Sasaki freezing medium (Niwa et al. 1989 Manual for Cryopreservation of Pig Spermatozoa 19–23; 1.0 × 109 sperm mL–1) using 0.5-mL straws. The sperm were cooled utilising the 2-step method, from 25 to 15°C at a rate of 0.17°C min–1, and then from 15 to 5°C at 0.08°C min–1. After cooling to 5°C, the straws were frozen in liquid nitrogen with 3% glycerol for storage. After storage for 0.5 to 21 months, the straws were thawed by immersion into a 37°C water bath. The recovered sperm were washed by centrifugation in PBS + 1 mg mL–1 BSA and were resuspended in either Beltsville thawing solution (Pursel and Johnson. 1975 J. Anim. Sci. 40, 99–102) for intra-fallopian AI or in porcine fertilization medium (PFM, Research Institute for the Functional Peptides, Yamagata, Japan) for IVF. Prepubertal gilts (6.5 months), in which oestrus was induced by 1000 IU eCG and 1500 IU hCG given 66 or 72 h apart, were surgically inseminated with 0.9–7.9 × 106 progressive motile sperm 41 to 51 h after receiving an hCG injection. Oocytes, which matured in vitro either in modified porcine oocyte medium (IFP) or modified NCSU23 medium, were inseminated in PFM for 8 h with either 0.5 (huKO, GalT-KO) or 1.6 (HNF-1α) × 106 progressive motile sperm mL–1. The in vitro fertilized oocytes were cultured in porcine zygote medium-5 (Research Institute for the Functional Peptides) for 5 to 6 days until they were transferred. Some of these oocytes were examined for their fertilization rates. Blastocysts were transferred into the uterus of the recipient 150 h after hCG treatment. The fertilization rates for huKO, HNF-1α and GalT-KO sperm were 63.5% (61/96), 62.5% (70/112) and 92.4% (61/66), respectively; 50.8% (31/61), 82.9% (58/70) and 60.7% (37/61) of these were monospermic. The rate at which the IVF embryos developed into blastocysts was 47.8–52.4%. This study demonstrates that IVF using frozen epididymal sperm is more efficient method for reproducing genetically modified pigs than AI (87.5 v. 33.3%). Table 1.Pig production efficiencies of frozen epididymal sperm from genetically modified pigs utilising AI and IVF This study was supported by JST, ERATO, NAKAUCHI Stem Cell and Organ Regeneration Project, Tokyo.

326 GENERATION OF A DOUBLE-TRANSGENIC PIG WITH PANCREAS-SPECIFIC GREEN AND LIVER-SPECIFIC RED FLUORESCENCE

Transgenic (Tg) pigs with organ/tissue-specific fluorescence expression provide invaluable research tools for many types of studies, such as organogenesis analysis, in vitro tissue generation from pluripotent cells, and progenitor/stem cell transplantation therapy. We aimed to develop a Tg pig characterised by pancreas- and liver-specific fluorescence expression. A 8.4 kb transgene construct expressing Venus (green fluorescence) under the control of the mouse Pdx1 (pancreatic duodenal homeobox-1) promoter and a BAC-derived construct (170 kb) consisting of the whole-length porcine albumin (Alb) promoter and humanized Kusabira-Orange (huKO, red fluorescence) was introduced into porcine in vitro-matured oocytes using the intracytoplasmic sperm injection (ICSI)-mediated gene transfer method. Injected embryos were transferred to the oviducts of oestrus-synchronized recipients after culture for 1 to 3 days. The transfer of 370 Pdx1-Venus embryos into 4 recipients produce 22 (5.9%) fetuses/piglets, and 9 (40.9%) Tg pigs exhibited pancreas-specific Venus expression. Two (1 male and 1 female) founder Pdx1-Venus-Tg pigs were mated with wild-type (WT) pigs and produced 32 offspring in 3 litters, of which 16 (50.0%) were transgenic. Pancreas-specific Venus expression was inherited in these Tg offspring. The transfer of 523 Alb-huKO embryos into 4 recipients resulted in 19 (3.6%) piglets including a Tg female, which showed liver-specific huKO fluorescent expression. Expression of huKO was detected by RT-PCR exclusively in liver, but not in 7 other organs/tissues examined, including heart, lung, stomach, small intestine, spleen, kidney and skin. This founder Tg female produced a total of 12 non-Tg and 5 Tg offspring (in 2 litters) after mating with a WT boar. Liver-specific huKO expression was inherited in these Tg offspring. Furthermore, the mating of a female Pdx1-Venus pig with an Alb-huKO boar yielded 7 non-Tg and 10 Tg pigs. Four of these Tg pigs carrying both of the transgenes exhibited both pancreas-specific Venus and liver-specific huKO expression in single individuals. Double-Tg pigs with pancreas-specific green fluorescence and liver-specific red fluorescence grew normally, and tests of their reproduction ability are currently underway. These data demonstrate that transgene introduction by ICSI-mediated gene transfer into in vitro-matured oocytes is a feasible option for generating pigs expressing fluorescent proteins in a tissue-specific manner.

67 A HOLLOW FIBER VITRIFICATION METHOD ENABLES CRYOBANKING OF IN VITRO-MATURATION/IN VITRO-FERTILIZATION-DERIVED TRANSGENIC PIG EMBRYOS

We have recently developed a novel high-performance embryo cryopreservation method: the hollow fiber vitrification (HFV) method (Matsunari et al. 2012 J. Reprod. Dev., in press). In this study, we aimed to demonstrate the utility of the HFV method for the cryopreservation of transgenic pig embryos produced by in vitro oocyte maturation/fertilization (IVM/IVF). In vitro-matured oocytes were inseminated with cryopreserved epididymal sperm (Kikuchi et al. 1998 Theriogenology 50, 615–623) from a transgenic pig carrying the humanized Kusabira-Orange gene (Matsunari et al. 2008 Cloning Stem Cell 10, 313–323) and then cultured for 96 h. Morulae with normal morphology were divided into the vitrification and nonvitrification groups. The vitrification of embryos was performed by the HFV method using 20-mM HEPES-buffered TCM199 containing 20% calf serum as a base medium. Cellulose acetate hollow fibers (25 mm), each containing 10 to 20 embryos, were placed in an equilibration solution containing 7.5% ethylene glycol and 7.5% dimethyl sulfoxide for 5 to 7 min and were then placed for 1 min in the vitrification solution containing 15% ethylene glycol, 15% dimethyl sulfoxide, and 0.5 M sucrose. The embryos were then vitrified by immersion in liquid nitrogen and held there for 5 to 10 min. The embryos were warmed by immersing the hollow fiber in a 1-M sucrose solution at 38.5°C, followed by a stepwise dilution of the cryoprotectants using 0.5-M sucrose solution (3 min) and the base medium (10 min). Vitrified and nonvitrified embryos were cultured for 40 h, and their development into blastocysts was evaluated. The in vitro development of vitrified embryos to the blastocyst stage was compared with that of the nonvitrified controls on Day 6. In the embryo-transfer experiments, blastocysts at either Day 5 or Day 6 from both the vitrification and nonvitrification groups were transferred to 3 recipient gilts per group (25–32 blastocysts/gilt), and their development through farrowing was compared. To test long-term preservation, some of the vitrified morulae were kept in liquid nitrogen for 43 days, and their development to Day 30 fetuses was evaluated after transfer to an additional recipient. The differences in proportional data between the 2 groups were analyzed with the χ2-test. Of the 393 putative zygotes obtained by IVM/IVF, 169 (43.0%) developed into morulae. In vitro development of the vitrified morulae to blastocysts (66/85, 77.6%) was comparable with that of the nonvitrified morulae (67/84, 79.8%, not significant: NS). The embryo-transfer experiments resulted in pregnancy in all 6 of the recipients. The production efficiency of piglets (piglets/embryos transferred) was 17/88 (19.3%) for the vitrification group and 27/88 (27.7%, NS) for the nonvitrification group. Approximately 50% of the offspring in both groups were transgenic. Long-term cryopreservation using the HFV method resulted in similar piglet production efficiency (7 piglets produced out of 32 embryos transferred). This study demonstrated for the first time that the HFV method effectively cryopreserves IVM/IVF-derived transgenic pig embryos. Supported by the JST CREST program.

Increased α1-antitrypsin levels in acute-phase Kawasaki disease as shown by SELDI-TOF MS analysis

Various agents have been suggested as causal or associated factors in the pathogenesis of Kawasaki disease (KD); however, the underlying factors of KD remain unknown. Plasma exchange is one of the most effective treatments for the acute phase of KD. This indicates that plasma may contain factors associated with the pathogenesis of KD. To search for proteins that may be involved in KD pathogenesis, we analyzed serum proteins with surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS). Serum samples were obtained from 17 KD patients. Serum from six of the patients was collected during acute phase before acetylsalicylic acid (ASA) and intravenous immunoglobulin administration (phase A1), during remission with ASA (phase A2), and during remission without any medication (phase A3). Serum from the remaining 11 patients was collected for phases A1 and A2 only. There were two age- and sex-matched control groups comprising 8 afebrile healthy children (group B) and 8 febrile children with several infectious diseases (group C). There were no statistical differences in laboratory examination between phase A1 and group C except for albumin level, alanine aminotransferase, or sodium level. Serum samples were analyzed by SELDI-TOF MS after purification. We detected five peaks, i.e., those were specifically increased or decreased during phase A1, and identified 1 of these as α1-antitrypsin (α1-AT). α1-AT can inhibit neutrophil elastase activity. This elastase is thought to play a role in coronary artery damage. Our findings present an interesting starting point for further investigations into the pathophysiology of KD.

Sub-two-cycle, carrier-envelope phase-stable, intense optical pulses at 1.6 μm from a BiB3O6 optical parametric chirped-pulse amplifier

We report on the generation of 9.0 fs, 550 μJ, carrier-envelope phase (CEP)-stabilized optical pulses around 1.6 μm at 1 kHz. Few-cycle IR pulses are obtained from a BiB(3)O(6) optical parametric chirped-pulse amplifier. The amplification of nearly octave-spanning ultrabroad pulses without spectral broadening results in good stability in output energy (0.85% rms) and CEP (160 mrad rms). We observed high harmonics in the water window from a neon cell that corresponds to a laser intensity of 4.1×10(14) W/cm(2).

Design of ridge filters for spread-out Bragg peaks with Monte Carlo simulation in carbon ion therapy

Spread-out Bragg peaks made by ridge filters or wheel range modulators are used in charged particle therapy with passive methods to achieve uniform biological responses in irradiated tumors. Following the biological responses needed to design the ridge filters, which were developed at the National Institute of Radiological Sciences in Japan, new ridge filters were designed using recent developments in heavy-ion reactions and dosimetry. The Monte Carlo code of Geant4 was used to calculate the qualities of carbon ion beams in a water phantom. The results obtained from the simulation were corrected so that they agreed with the measurements of depth dose distributions. The calculations of biological responses to fragments other than carbon ions were assumed to be for helium ions. The measured dose distributions with the designed ridge filters were compared to the calculated distributions. A beam modifying system using this adaptable method was successively applied to carbon ion therapy at Gunma University.

The STAT5b Pathway Defect and Autoimmunity

The signal transducer and activator of transcription (STAT) 5b is a universal transcription factor that plays key biological roles in allergic diseases, immunodeficiencies, autoimmunities, cancers, hematological diseases, growth disorders, and lung diseases. The identification of distinct pathological manifestations of STAT5b deficiency in humans has highlighted the critical role of the STAT5b pathway. Proper gene transcription at IL-2R α, FOXP3, Bcl-2, and growth hormone (GH) associated loci are thought to be associated with normal STAT5b transcriptional activity. These genes are thought to play important roles in allergy/autoimmunity, immunodeficiency, cancer/anemia, and growth, respectively. The STAT5A and STAT5B genes are collocated on 17q11. Although these two monomeric proteins exhibit peptide sequence similarities of >90%, it is known through observations of STAT5b deficient subjects that STAT5a and STAT5b are not fully redundant in humans. Patients with STAT5b deficiency have decreased numbers of regulatory CD4⁺CD25^high T cell (Treg) despite their STAT5a levels being normal. Prior studies on STAT5b deficient subjects have revealed immunological aberrations associated with the following disease phenotype: modest lymphopenia and decreased populations of Treg, γ−δ T cells, and natural killer (NK) cells. Most subjects with STAT5b deficiency show severe eczema, and autoimmune disease (juvenile idiopathic arthritis, autoimmune thyroiditis, idiopathic thrombocytic purpura) which are thought to be associated with Treg dysfunction. We will review the likely pathophysiological mechanisms associated with STAT5b deficiency.

Hollow fiber vitrification provides a novel method for cryopreserving in vitro maturation/fertilization-derived porcine embryos

In vitro matured (IVM) oocytes have been used to create genetically modified pigs for various biomedical purposes. However, porcine embryos derived from IVM oocytes are very cryosensitive. Developing improved cryopreservation methods would facilitate the production of genetically modified pigs and also accelerate the conservation of genetic resources. We recently developed a novel hollow fiber vitrification (HFV) method; the present study was initiated to determine whether this new method permits the cryopreservation of IVM oocyte-derived porcine embryos. Embryos were created from the in vitro fertilization of IVM oocytes with frozen-thawed sperm derived from a transgenic pig carrying a humanized Kusabira-Orange (huKO) gene. Morula-stage embryos were assigned to vitrification and nonvitrification groups to compare their in vitro and in vivo developmental abilities. Vitrified morulae developed to the blastocyst stage at a rate similar to that of nonvitrified embryos (66/85, 77.6% vs. 67/84, 79.8%). Eighty-eight blastocysts that developed from vitrified morulae were transferred into the uteri of three recipient gilts. All three became pregnant and produced a total of 17 piglets (19.3%). This piglet production was slightly lower, albeit not significantly, than that of the nonvitrification group (27/88, 30.7%). Approximately half of the piglets in the vitrification (10/17, 58.8%) and nonvitrification (15/27, 55.6%) groups were transgenic. There was no significant difference in the growth rates among the piglets in the two groups. These results indicate that the HFV method is an extremely effective method for preserving cryosensitive embryos such as porcine in vitro maturation/fertilization-derived morulae.