Increase of GADD34 expression in skeletal muscle by ATRA

All-trans retinoic acid (ATRA) increases the sensitivity to unfolded protein response in differentiating leukemic blasts. The downstream transcriptional factor of PERK, a major arm of unfolded protein response, regulates muscle differentiation. However, the role of growth arrest and DNA damage-inducible protein 34 (GADD34), one of the downstream factors of PERK, and the effects of ATRA on GADD34 expression in muscle remain unclear. In this study, we identified ATRA increased the GADD34 expression independent of the PERK signal in the gastrocnemius muscle of mice. ATRA up-regulated GADD34 expression through the transcriptional activation of GADD34 gene via inhibiting the interaction of homeobox Six1 and transcription co-repressor TLE3 with the MEF3-binding site on the GADD34 gene promoter in skeletal muscle. ATRA also inhibited the interaction of TTP, which induces mRNA degradation, with AU-rich element on GADD34 mRNA via p-38 MAPK, resulting in the instability of GADD34 mRNA. Overexpressed GADD34 in C2C12 cells changes the type of myosin heavy chain in myotubes. These results suggest ATRA increases GADD34 expression via transcriptional and post-transcriptional regulation, which changes muscle fiber type

Fertilization Recovery after Defective Sperm Cell Release in Arabidopsis

SummaryIn animal fertilization, multiple sperms typically arrive at an egg cell to “win the race” for fertilization. However, in flowering plants, only one of many pollen tubes, conveying plant sperm cells, usually arrives at each ovule that harbors an egg cell [1, 2]. Plant fertilization has thus been thought to depend on the fertility of a single pollen tube [1]. Here we report a fertilization recovery phenomenon in flowering plants that actively rescues the failure of fertilization of the first mutant pollen tube by attracting a second, functional pollen tube. Wild-type (WT) ovules of Arabidopsis thaliana frequently (∼80%) accepted two pollen tubes when entered by mutant pollen defective in gamete fertility. In typical flowering plants, two synergid cells on the side of the egg cell attract pollen tubes [3–5], one of which degenerates upon pollen tube discharge [3, 6]. By semi-in vitro live-cell imaging [7, 8] we observed that fertilization was rescued when the second synergid cell accepted a WT pollen tube. Our results suggest that flowering plants precisely control the number of pollen tubes that arrive at each ovule and employ a fertilization recovery mechanism to maximize the likelihood of successful seed set

Higgs mechanism and superconductivity in U(1) lattice gauge theory with dual gauge fields

We introduce a U(1) lattice gauge theory with dual gauge fields and study its phase structure. This system is motivated by unconventional superconductors like extended s-wave and d-wave superconductors in the strongly-correlated electron systems. In this theory, the "Cooper-pair" field is put on links of a cubic lattice due to strong on-site repulsion between electrons in contrast to the ordinary s-wave Cooper-pair field on sites. This Cooper-pair field behaves as a gauge field dual to the electromagnetic U(1) gauge field. By Monte Carlo simulations we study this lattice gauge model and find a first-order phase transition from the normal state to the Higgs (superconducting) state. Each gauge field works as a Higgs field for the other gauge field. This mechanism requires no scalar fields in contrast to the ordinary Higgs mechanism.Comment: 4 pages, 6 figure

Pulmonary Artery Leiomyosarcoma Diagnosed without Delay

A 63-year-old female presented with abnormal lung shadows but had, apart from this, few symptoms. Computed tomography (CT) revealed multiple nodules and blockage of the pulmonary artery. She was immediately diagnosed with pulmonary artery sarcoma based on a careful differential diagnosis and underwent surgery. Her tumor was pathologically diagnosed as leiomyosarcoma (i.e. intimal sarcoma). Pulmonary artery sarcoma can be easily confounded with thromboembolism in a clinical setting and some cases are diagnosed post mortem only. In our case, clinical prediction scores (Wells score, Geneva score, and revised Geneva score) for the pulmonary embolism showed low probability. Moreover, chest CT showed uncommon findings for pulmonary thromboembolism, as the nodules were too big for thrombi. Because surgical resection can provide the only hope of long-term survival in cases of pulmonary artery sarcoma, clinicians should consider this possibility in the differential diagnosis of pulmonary embolism. Clinical prediction scores and CT findings might help to reach the correct diagnosis of pulmonary artery sarcoma

Porencephaly in a Cynomolgus Monkey (Macaca Fascicularis)

Porencephaly was observed in a female cynomolgus monkey (Macaca fascicularis) aged 5 years and 7 months. The cerebral hemisphere exhibited diffuse brownish excavation with partial defects of the full thickness of the hemispheric wall, and it constituted open channels between the lateral ventricular system and arachnoid space. In addition, the bilateral occipital lobe was slightly atrophied. Histopathologically, fibrous gliosis was spread out around the excavation area and its periphery. In the roof tissue over the cavity, small round cells were arranged in the laminae. They seemed to be neural or glial precursor cells because they were positive for Musashi 1 and negative for NeuN and GFAP. In the area of fibrous gliosis, hemosiderin or lipofuscin were deposited in the macrophages, and activated astroglias were observed extensively around the excavation area

Onset of instability with collapse observed in relatively high density and medium beta regions of LHD

Edge MHD instabilities with pressure collapse are found in relatively high beta and low magnetic Reynolds number regions with a magnetic axis torus outward-shifted configuration of the large helical device (LHD), and characteristics and onset conditions of the instability are investigated. The instability has a radial structure with an odd parity around the resonant surface, which is different from that of the interchange instability typically observed in the LHD. The onset condition dependence on the magnetic axis location shows that the onset beta increases as the magnetic axis location moves more torus inwardly, and the instability appears only in limited configurations where the magnetic axis is located between 3.65 and 3.775 m. In such configurations, the resonant surface location is close to an index of the plasma boundary. This fact suggests that the distance between the resonant surface location and the plasma boundary plays an important role in the onset, and a possibility that the instability is driven by an external mode

Detection of RBM15-MKL1 Fusion Was Useful for Diagnosis and Monitoring of Minimal Residual Disease in Infant Acute Megakaryoblastic Leukemia

Acute megakaryocytic leukemia (AMKL) with t(1;22)(p13;q13) is a distinct category of myeloid leukemia by WHO classification and mainly reported in infants and young children. Accurate diagnosis of this type of AMKL can be difficult, because a subset of patients have a bone marrow (BM) blast percentage of less than 20% due to BM fibrosis. Therefore, it is possible that past studies have underestimated this type of AMKL. We present here the case of a 4-month-old female AMKL patient who was diagnosed by presence of the RBM15-MKL1 (OTT-MAL) fusion transcript by RT-PCR. In addition, we monitored RBM15-MKL1 fusion at several time points as a marker of minimal residual disease (MRD), and found that it was continuously negative after the first induction chemotherapy even by nested RT-PCR. Detection of the RBM15-MKL1 fusion transcript thus seems to be useful for accurate diagnosis of AMKL with t(1;22)(p13;q13). We recommend that the RBM15-MKL1 fusion transcript be analyzed for all suspected AMKL in infants and young children. Furthermore, monitoring of MRD using this fusion transcript would be useful in treatment of AMKL with t(1;22)(p13;q13)

External RMP effect on locked-mode-like instability in helical plasmas

The slowing-down mechanism of the locked-mode-like instabilities with and without an island structure is investigated through the effects of an external RMP (resonant magnetic perturbation) on the instabilities. For both instabilities, the slowing-down duration decreases with the increase in the external RMP, and the RMP dependence is consistent with the braking model of the j × B force due to the interaction between the instabilities and the external RMP. Moreover, the relationship between the amplitude and the frequency of both locked-mode-like instabilities during the slowing down is consistent with the force balance model between the j × B force due to the external RMP and a viscous force. These results suggest that the slowing down of both locked-mode-like instabilities with finite external RMP occurs due to the j × B force driven by the external RMP