Direct Injection of CRISPR/Cas9-Related mRNA into Cytoplasm of Parthenogenetically Activated Porcine Oocytes Causes Frequent Mosaicism for Indel Mutations

Some reports demonstrated successful genome editing in pigs by one-step zygote microinjection of mRNA of CRISPR/Cas9-related components. Given the relatively long gestation periods and the high cost of housing, the establishment of a single blastocyst-based assay for rapid optimization of the above system is required. As a proof-of-concept, we attempted to disrupt a gene (GGTA1) encoding the α-1,3-galactosyltransferase that synthesizes the α-Gal epitope using parthenogenetically activated porcine oocytes. The lack of α-Gal epitope expression can be monitored by staining with fluorescently labeled isolectin BS-I-B₄ (IB4), which binds specifically to the α-Gal epitope. When oocytes were injected with guide RNA specific to GGTA1 together with enhanced green fluorescent protein (EGFP) and human Cas9 mRNAs, 65% (24/37) of the developing blastocysts exhibited green fluorescence, although almost all (96%, 23/24) showed a mosaic fluorescent pattern. Staining with IB4 revealed that the green fluorescent area often had a reduced binding activity to IB4. Of the 16 samples tested, six (five fluorescent and one non-fluorescent blastocysts) had indel mutations, suggesting a correlation between EGFP expression and mutation induction. Furthermore, it is suggested that zygote microinjection of mRNAs might lead to the production of piglets with cells harboring various mutation types.     

Quantitative risk assessment using a Japanese hydrogen refueling station model

Although hydrogen refueling stations (HRSs) are becoming widespread across Japan and are essential for the operation of fuel cell vehicles, they present potential hazards. A large number of accidents such as explosions or fires have been reported, rendering it necessary to conduct a number of qualitative and quantitative risk assessments for HRSs. Current safety codes and technical standards related to Japanese HRSs have been established based on the results of a qualitative risk assessment and quantitative effectiveness validation of safety measures over ten years ago. In the last decade, there has been much development in the technologies of the components or facilities used in domestic HRSs and much operational experience as well as knowledge to use hydrogen in HRSs safely have been gained through years of commercial operation. The purpose of the present study is to conduct a quantitative risk assessment (QRA) of the latest HRS model representing Japanese HRSs with the most current information and to identify the most significant scenarios that pose the greatest risks to the physical surroundings in the HRS model. The results of the QRA show that the risk contours of 10^?3 and 10^?4 per year were confined within the HRS boundaries, whereas the risk contours of 10^?5 and 10^?6 per year are still present outside the HRS. Comparing the breakdown of the individual risks (IRs) at the risk ranking points, we conclude that the risk of jet fire demonstrates the highest contribution to the risks at all of the risk ranking points and outside the station. To reduce these risks and confine the risk contour of 10^?6 per year within the HRS boundaries, it is necessary to consider risk mitigation measures for jet fires.     

Hopping and optical absorption of electrons in nano-porous crystal 12CaO·7Al2O3

Recently it has been discovered that a nano-porous main group oxide 12CaO·7Al₂O₃ (C12A7) can be converted from a wide-gap insulator to a good transparent conductor. Using ab initio modelling we explain good conductivity of this material by very small barriers for hopping of localised electrons between neighbouring positive cages. We show that optical absorption of C12A7 in infrared region and at energies higher than 2.7 eV is due to inter-cage and intra-cage electron transitions, respectively. The proposed mechanisms can be useful in further search for conducting transparent media.     

Magnet Safety Assessment for ITER

The ITER magnet system consists of structurally linked sets of toroidal (TF) and poloidal (PF) field coils, central solenoid (CS), and various support structures. The coils are superconducting, force flow Helium cooled with a Kapton-Glass-Epoxy multilayer insulation system. The stored magnetic energy is about 100GJ in the TF system and 20GJ in the PF-CS. Coils and structure are maintained at 4 K by enclosing them in a vacuum cryostat. The cryostat, comprising an outer envelope to the magnets, forms most of the second radioactivity confinement barrier. The inner primary barrier is formed by the vacuum vessel, its ports and their extensions. To keep the machine size within acceptable bounds, it is essential that the magnets are in close proximity to both of the nuclear confinement barriers. The objective of the magnet design is that, although local damage to one of the barriers may occur in very exceptional circumstances, large scale magnet structural or thermal failure leading to simultaneous breaching of both barriers is not credible. Magnet accidents fall into three categories: thermal (which includes arcing arising from insulation failure and local overheating due to discharge failure in the event of a superconductor quench), structural (which includes component mechanical failure arising from material inadequacies, design errors and exceptional force patterns arising from coil shorts or control failures), and fluid (Helium release due to cooling line failure). After a preliminary survey to select initial faults conceivable within the present design, these faults are systematically analyzed to provide an assessment of the damage potential. The results of this damage assessment together with an assessment of the reliability of the monitoring and protective systems, shows that the magnets can operate with the required safety condition.     

A 300-MHz 25-/spl mu/A/Mb-leakage on-chip SRAM module featuring process-variation immunity and low-leakage-active mode for mobile-phone application processor

An on-chip 1-Mb SRAM suitable for embedding in the application processor used in mobile cellular phones was developed. This SRAM supports three operating modes - high-speed active mode, low-leakage low-speed active mode, and standby mode - and uses a subdivisional power-line control (SPC) scheme. The combination of three operating modes and the SPC scheme realizes low-power operation under actual usage conditions. It operates at 300 MHz, with leakage of 25 /spl mu/A/Mb in standby mode, and 50 /spl mu/A/Mb at the low-leakage active mode. This SRAM also uses a self-bias write scheme that decreases of minimum operating voltage by about 100 mV.     

Hydrothermal corrosion of magnesiapartially-stabilized zirconia

Changes in the phase compositions and microstructures of magnesia-partially-stabilized zirconia (Mg-PSZ) were studied in water at 80–300 °C, 1 m HCl solutions at 80–140 °C and 1 m CH₃COOH-CH₃COONa buffer solutions at pH 3 and 80–140 °C for 10–40 days. The tetragonal to monoclinic phase transformation and the degradation of the fracture strength occurred in water above 200 °C. On the other hand, although no noticeable tetragonal to monoclinic phase transformation proceeded in 1 m HCl solutions and 1 m CH₃COOH-CH₃-COONa buffer solutions at pH 3 below 140 °C, the fracture strength of Mg-PSZ greatly degraded. The dissolution of Mg²⁺ ion was observed in water above 200 °C and in 1 m HCl solutions above 80 °C.     

Amyloid beta-protein deposition in the leptomeninges and cerebral cortex

To further investigate the process of amyloid beta-protein (Abeta) deposition, we determined, using sensitive enzyme immunoassays, the levels of Abeta40 and Abeta42 (Abetas) in the soluble and insoluble fractions of the leptomeninges (containing arachnoid mater and leptomeningeal vessels) and cerebral cortices from elderly control subjects showing various stages of Abeta deposition and from patients affected by Alzheimer's disease (AD). In both locations, insoluble Abeta levels were higher by orders of magnitude than soluble Abeta levels. Soluble Abeta levels in cortices were much lower than those in leptomeninges. In insoluble Abeta in the cortex, Abeta42 was by far the predominant species, and Abeta42 in AD cortices was characterized by the highest degree of modifications in the amino terminus. In contrast, this Abeta42 predominance was not observed in insoluble Abeta in the leptomeninges, which were found to be able to accumulate Abetas to an extent similar to that in the cortex, on a weight basis. The levels of insoluble Abeta in the leptomeninges or cortex generally correlated with the degree of cerebral amyloid angiopathy or the abundance of senile plaque, respectively. However, the presence of plaque-free cortical samples showing significant levels of insoluble Abeta42 suggests that biochemically detectable Abeta accumulation precedes immunocytochemically detectable Abeta deposition in the cortex.     

Exchangeability of actin in cardiac myocytes and fibroblasts as determined by fluorescence photobleaching recovery

OBJECTIVE: To assess whether hypertension is a risk factor for hysterectomy performed for benign diseases. METHODS: Self-report questionnaires were collected from 77% of 2301 Danish women aged 30, 40, 50, or 60 years selected at random in 1982 for a prevalence study. Information about cardiovascular diseases, hypertension, use of medicine, weight and dieting history, life-styles, psychologic factors, gynecologic history (including history of hysterectomy), and social background were recorded. Weight, height, and blood pressure were measured. In an incidence study, the cohort was followed during 1982-1990 via central registers to assess the incidence of hysterectomy. Logistic and Cox regressions were used to analyze data. RESULTS: In the prevalence study, history of hypertension partly explained the relation between hysterectomy and cardiovascular diseases. In the incidence study, history of hypertension and use of diuretics were significant risk factors for hysterectomy. After confounder control, use of diuretics was explained by weight-related variables, and hypertension was a risk factor for hysterectomy in educated women (adjusted relative risk [RR] 2.88, 95% confidence interval [CI] 1.07, 7.76) and in women with weight fluctuations (adjusted RR 3.31, 95% CI 1.35, 8.14). Weight cycling and lack of education remained significant risk factors for hysterectomy in women with and without hypertension, respectively. CONCLUSION: History of hypertension, weight cycling, and lack of education are closely related risk factors for premenopausal hysterectomy. These three risk factors contribute to women undergoing hysterectomy having an increased risk for cardiovascular diseases. We proposed that hypertension might be a plausible biological cause of menorrhagia and an indication for hysterectomy.