One-Step Synthesis of Copper and Cupric Oxide Particles from the Liquid Phase by X-Ray Radiolysis Using Synchrotron Radiation

The deposition of copper (Cu) and cupric oxide (Cu4O3, Cu2O, and CuO) particles in an aqueous copper sulfate (CuSO4) solution with additive alcohol such as methanol, ethanol, 2-propanol, and ethylene glycol has been studied by X-ray exposure from synchrotron radiation. An attenuated X-ray radiation time of 5 min allows for the synthesis of Cu, Cu4O3, Cu2O, and CuO nano/microscale particles and their aggregation into clusters. The morphology and composition of the synthesized Cu/cupric oxide particle clusters were characterized by scanning electron microscopy, scanning transmission electron microscopy, and high-resolution transmission electron microscopy with energy dispersive X-ray spectroscopy. Micro-Raman spectroscopy revealed that the clusters comprised cupric oxide core particles covered with Cu particles. Neither Cu/cupric oxide particles nor their clusters were formed without any alcohol additives. The effect of alcohol additives is attributed to the following sequential steps: photochemical reaction due to X-ray irradiation induces nucleation of the particles accompanying redox reaction and forms a cluster or aggregates by LaMer process and DLVO interactions. The procedure offers a novel route to synthesize the Cu/cupric oxide particles and aggregates. It also provides a novel additive manufacturing process or lithography of composite materials such as metal, oxide, and resin

Regulated motion of glycoproteins revealed by direct visualization of a single cargo in the endoplasmic reticulum

The quality of cargo proteins in the endoplasmic reticulum (ER) is affected by their motion during folding. To understand how the diffusion of secretory cargo proteins is regulated in the ER, we directly analyze the motion of a single cargo molecule using fluorescence imaging/fluctuation analyses. We find that the addition of two N-glycans onto the cargo dramatically alters their diffusion by transient binding to membrane components that are confined by hyperosmolarity. Via simultaneous observation of a single cargo and ER exit sites (ERESs), we could exclude ERESs as the binding sites. Remarkably, actin cytoskeleton was required for the transient binding. These results provide a molecular basis for hypertonicity-induced immobilization of cargo, which is dependent on glycosylation at multiple sites but not the completion of proper folding. We propose that diffusion of secretory glycoproteins in the ER lumen is controlled from the cytoplasm to reduce the chances of aggregation

Gene Targeting and Subsequent Site-Specific Transgenesis at the beta-actin (ACTB) Locus in Common Marmoset Embryonic Stem Cells

Nonhuman primate embryonic stem (ES) cells have vast promise for preclinical studies. Genetic modification in nonhuman primate ES cells is an essential technique for maximizing the potential of these cells. The common marmoset (Callithrix jacchus), a nonhuman primate, is expected to be a useful transgenic model for preclinical studies. However, genetic modification in common marmoset ES (cmES) cells has not yet been adequately developed. To establish efficient and stable genetic modifications in cmES cells, we inserted the enhanced green fluorescent protein (EGFP) gene with heterotypic lox sites into the beta-actin (ACTB) locus of the cmES cells using gene targeting. The resulting knock-in ES cells expressed EGFP ubiquitously under the control of the endogenous ACTB promoter. Using inserted heterotypic lox sites, we demonstrated Cre recombinase-mediated cassette exchange (RMCE) and successfully established a monomeric red fluorescent protein (mRFP) knock-in cmES cell line. Further, a herpes simplex virus-thymidine kinase (HSV-tk) knock-in cmES cell line was established using RMCE. The growth of tumor cells originating from the cell line was significantly suppressed by the administration of ganciclovir. Therefore, the HSV-tk/ganciclovir system is promising as a safeguard for stem cell therapy. The stable and ubiquitous expression of EGFP before RMCE enables cell fate to be tracked when the cells are transplanted into an animal. Moreover, the creation of a transgene acceptor locus for site-specific transgenesis will be a powerful tool, similar to the ROSA26 locus in mice

A history of mild shocks experienced by the regolith particles on hydrated asteroid Ryugu

Micrometeorites, a possible major source of Earth’s water, are thought to form from explosive dispersal of hydrated chondritic materials during impact events on their parental asteroids. However, this provenance and formation mechanism have yet to be directly confirmed using asteroid returned samples. Here, we report evidence of mild shock metamorphism in the surface particles of asteroid Ryugu based on electron microscopy. All particles are dominated by phyllosilicates but lack dehydration textures, which are indicative of shock-heating temperatures below ~500 °C. Microfault-like textures associated with extensively shock-deformed framboidal magnetites and a high-pressure polymorph of Fe–Cr–sulfide have been identified. These findings indicate that the average peak pressure was -2 GPa. The vast majority of ejecta formed during impact on Ryugu-like asteroids would be hydrated materials, larger than a millimetre, originating far from the impact point. These characteristics are inconsistent with current micrometeorite production models, and consequently, a new formation mechanism is required

Oxygen isotope evidence from Ryugu samples for early water delivery to Earth by CI chondrites

The delivery of water to the inner Solar System, including Earth, is still a debated topic. A preferential role for hydrated asteroids in this process is supported by isotopic measurements. Carbonaceous chondrite (CC) meteorites represent our main source of information about these volatile-rich asteroids. However, the destruction of weaker materials during atmospheric entry creates a bias in our CC data. The return of surface materials from the C-type asteroid 162173 Ryugu by the Hayabusa2 spacecraft provides a unique opportunity to study high-porosity, low-density, primitive materials, unrepresented in the meteorite record. We measured the bulk oxygen isotope composition from four Ryugu particles and show that they most closely resemble the rare CI (CC Ivuna-type) chondrites, but with some differences that we attribute to the terrestrial contamination of the CI meteorites. We suggest that CI-related material is widespread among carbonaceous asteroids and a more important source of Earth’s water and other volatiles than its limited presence in our meteoritic collection indicates

ソウキ ノ ゼンシン ステロイド リョウホウ ニヨリ キドウ ノ ハンコン キョウサク オ カイヒ デキタ キカンシ ケッカク ノ 1ショウレイ

35歳男性.入院約6週前より喀痰,咳嗽出現.数日前に左上肺空洞影指摘,喀痰中抗酸菌(3+)検出され入院.INH,RFP,PZA 及びEB による標準化学療法が開始された.咳嗽,呼吸困難,両肺野狭窄音聴取及び多量排菌持続し,気管支鏡所見上気管〜両側主気管支に隆起性潰瘍病変を認め,気管支結核を確定.高度の呼吸器症状遷延のため中等量のステロイド点滴投与を開始し,症状ならびに気道粘膜病変は改善した.高率に気管・気管支瘢痕収縮へ移行しうる気道粘膜像であったが,中等量の全身ステロイド療法により回避された.気道瘢痕狭窄回避のため,気管支結核活動性病変には中等量以上の全身ステロイド療法を考慮すべきと考えられた.A 35-year-old man admitted to the hospital because of acavitary lesion in the lung and acid-fast bacilli (AFB) (3+) in a sputum specimen, a polymerase-chain-reaction ofwhich revealed positive for M. tuberculosis. He had beenwell until approximately 6 weeks before admission, whenproductive cough developed. He also had temperature of upto 38 ℃, hoarseness, and shortness of breath couple of daysbefore. Intractable cough, dyspnea, wheeze in both lungfields, and numerous AFB in a sputum sustained, despiteprompt introduction of conventional chemotherapy containingINH, rifampicin, pyrazinamide, and ethambutol. Diagnosisof EBTB was confirmed by fibroptic bronchoscopy,which revealed granulomatous ulceration in the mucosa oftrachea and both main bronchi. Accordingly, intravenousmedium-dose methylprednisolone was administered, resultingrelief from serious respiratory manifestation and avoidanceof cicatricial stenosis of trachea and bronchi. This outcomesuggested that the current early intervention withglucocorticoid should be considered in serious active lesionof tracheal and bronchial mucosa in patients with EBTB

A pristine record of outer Solar System materials from asteroid Ryugu’s returned sample

Volatile and organic-rich C-type asteroids may have been one of the main sources of Earth’s water. Our best insight into their chemistry is currently provided by carbonaceous chondritic meteorites, but the meteorite record is biased: only the strongest types survive atmospheric entry and are then modified by interaction with the terrestrial environment. Here we present the results of a detailed bulk and microanalytical study of pristine Ryugu particles, brought to Earth by the Hayabusa2 spacecraft. Ryugu particles display a close compositional match with the chemically unfractionated, but aqueously altered, CI (Ivuna-type) chondrites, which are widely used as a proxy for the bulk Solar System composition. The sample shows an intricate spatial relationship between aliphatic-rich organics and phyllosilicates and indicates maximum temperatures of ~30 °C during aqueous alteration. We find that heavy hydrogen and nitrogen abundances are consistent with an outer Solar System origin. Ryugu particles are the most uncontaminated and unfractionated extraterrestrial materials studied so far, and provide the best available match to the bulk Solar System composition

鶏におけるB複合体 : 血液型システムから主要組織適合複合体への発展

鶏の主要組織適合複合体は最初Bシステムと名付けられた血液型システムとして見出された。B血液型に関する初期の研究は、この血液型が生理機能と関連していることを示唆した。その後,Bシステムは種々の免疫機能にも関連していることが見出され、このシステムは鶏における主要組織適合複合体であることが判明した。そこで、このシステムは現在、一般にB複合体と呼ばれている。B複合体は、B-G、B-FおよびB-Lと名付けられた三つの領域より成り、哺乳類の主要組織適合複合体と同様に、多くの機能に関与している。B複合体の各領域のDNA レベルでの構造については、現在徐々に明らかにされてきている。本論文ではB血液型から主要組織複合体への研究の発展過程とB複合体に関する研究の現状について総説的に紹介した。The major histocompatibility complex (MHC) in chickens was initially described as a blood group locus called the B system. Early studies on the B blood group system re-vealed that the B system was associated with some physiological functions. Subsequently, it was found that the B system was associated with several immunological functions and should be the MHC in chickens.Then, the system is now called the B complex. The B complex is composed of three regions, B-G, B-F and B-L, and regulates a number of functions similar to those found in mammalian MHC. The DNA structure of each region within the B complex is now gradually becoming clear

Inhibitory effect of histamine on the potentials recorded from the VPM and RF evoked by stimulation of the tooth pulp

The effect of histamine (Hi) on the evoked potentials recorded from the nucleus ventralis posteromedialis thalami (VPM) and the midbrain reticular formation (RF) was studied in unanesthetized rabbits. Under pentobarbital anesthesia, the recording electrodes were implanted stereotaxically into the VPM and RF, and stimulating electrodes were inserted into the tooth pulp of both incisors of rabbits. To maintain a high electrical resistance between the stimulating electrodes, attention was paid to selecting a suitable material for protecting the soldering point. When the tooth pulp was stimulated by the repetition of square wave pulses either ipsilaterally or contralaterally, similar evoked potentials were recorded at the VPM and RF. The potentials were biphasic consisting of an initial negative deflection followed by a positive deflection. Contralateral stimulation induced larger amplitude waves with shorter latencies than those of ispilateral stimulation. Intraventricular administration of Hi decreased the amplitudes of evoked potentials in a dose-dependent fashion. The effect of 200 μg of Hi corresponds to that produced by intravenous administration of 2 mg/kg of morphine. When the same dose of Hi was given together with 20 μg of pyrilamine, the depression of the potentials was eliminated remarkably, but visible alteration was not brought about by simultaneous administration of cimetidine