235 research outputs found
Circularly polarized gravitational waves in Chern-Simons gravity originated from an axion domain wall
We study a scattering problem of gravitational waves (GWs) by an axion domain
wall in Chern-Simons (CS) gravity. We find that circular polarization of GWs is
produced after passing through the domain wall. It turns out that the circular
polarization is sizable if the frequency of the GW is comparable to a critical
value determined by the characteristic CS length scale and the energy scale of
the axion domain wall. Thus, observations of the circular polarization could
give a stringent constraint on the characteristic CS length scale or could be a
new avenue to search for axion.Comment: 17 pages, 2 figure
The Greenish Flower Phenotype of Habenaria radiata (Orchidaceae) Is Caused by a Mutation in the SEPALLATA-Like MADS-Box Gene HrSEP-1
In Arabidopsis thaliana, the E-class SEPALLATA (SEP) genes are generally expressed across all floral whorls. These genes play fundamental roles in floral organ fate determination during development by interacting with other MADS-box gene products, such as those from A-, B-, and C-class genes. However, the function of SEP genes in orchid remains obscure. Here, we analyzed a mutant orchid cultivar with greenish flowers in Habenaria radiata and found that this phenotype is caused by the absence of SEP function. Wild type H. radiata flowers contain a column and two perianth whorls consisting of three greenish sepals, two white petals, and a lip (labellum). By contrast, the flowers of H. radiata cultivar âRyokuseiâ appear greenish, with three normal sepals in whorl 1, two greenish petals and a lip in whorl 2, and several sepaloid organs and a ventral column in whorls 3 and 4. We isolated two SEP-like genes (HrSEP-1 and HrSEP-2) and two AGAMOUS-like genes (HrAG-1 and HrAG-2) from wild type H. radiata and compared their expression in the wild type vs. the mutant cultivar. HrAG-1 and HrAG-2 were expressed in the column in the wild type, whereas these genes were expressed in the ventral column and in sepaloid organs that had been converted from a column in âRyokusei.â HrSEP-1 and HrSEP-2 were expressed in all floral organs in the wild type. However, in the mutant cultivar, HrSEP-2 was expressed in all floral organs, while HrSEP-1 expression was not detected. Thus, we analyzed the genomic structures of HrSEP-1 in the wild type and âRyokuseiâ and identified a retrotransposon-like element in its first exon in âRyokusei.â Yeast two-hybrid assays demonstrated that HrSEP-1 interacts with HrDEF, HrAG-1, and HrAG-2. These results indicate that the mutant phenotype of âRyokuseiâ flowers is caused by the loss of function of HrSEP-1. Therefore, this gene plays an important role in column, lip, and petal development in H. radiata flowers
An Adult Case of Kawasaki Disease in a Pregnant Japanese Woman: A Case Report
Kawasaki disease is an acute febrile disease predominantly seen in young children. We report a case of Kawasaki disease in a 32-year-old pregnant woman. She developed a generalized erythematous skin rash accompanied by high fever. Bilateral conjunctival congestion, tender cervical lymphadenopathy, an edematous lower lip and peripheral edema followed by desquamation were observed. She was successfully treated with aspirin and intravenous gammaglobulin (1 g/kg/day). Her course was not complicated by coronary artery aneurysm and she delivered a healthy baby. To the best of our knowledge, this is the first case of Kawasaki disease in a pregnant woman. We suggest that Kawasaki disease should be included in the differential diagnosis of a generalized, erythematous skin rash accompanied by high fever in adults
Origin of purple asparagus cultivar âPacific Purpleâ based on the sequence of sex determination gene
Garden asparagus is one of the most important crops worldwide. Since this crop is dioecious and male plants generally have higher yields compared to female plants, several DNA markers for sex identification have been developed for acceleration of asparagus breeding. Among these markers, Asp1-T7sp and MSSTS710 were found to be effective in sex determination for many asparagus cultivars. However, we previously found that these markers were not completely suitable for sex identification in the purple asparagus cultivar âPacific Purpleâ. There are two types of male individuals in this cultivar: One type is PP-m, which is identified the sex type by Asp1-T7sp and MSSTS710 markers, while the other type is PP-m* whose sex type is not identified by these markers. Since the sex identification markers are located on the non-recombining Y region, it was expected that the sequence around this region might be different between PP-m and PP-m*. In this study, the sequence of one of the sex-determining genes, MSE1/AoMYB35/AspTDF1, was analyzed, and a comparative analysis was conducted among PP-m and PP-m* of âPacific Purpleâ, A. officinalis and related species A. maritimus. The results revealed that PP-m and PP-m* has the similar sequence of MSE1/AoMYB35/AspTDF1 gene from A. officinalis and A. maritimus, respectively. âPacific Purpleâ is a cultivar developed through polycross hybrid from Italian landrace âVioletto dâAlbengaâ (VA), suggesting that VA originated from an interspecific crossing between A. officinalis and A. maritimus and that the pollen parent used in âPacific Purpleâ breeding contained two types of male individuals with different MSE1/AoMYB35/AspTDF1 sequence. As a result, PP-m and PP-m* of âPacific Purpleâ harbors the similar sequences of the MSE1/AoMYB35/AspTDF1 gene from A. officinalis and A. maritimus, respectively
Enhanced clickability of doubly sterically-hindered aryl azides
Steric character is one of the most fundamental factors to determine the reactivity of the substrate in organic synthesis. In bimolecular reaction, the sterically-bulky group situated close to the reactive center generally prevents the approach of the reaction partner retarding the bond formation. This report describes, to the contrary, significantly enhanced reactivity of 2,6-disubstituted phenyl azides observed in catalyst-free 1,3-dipolar cycloaddition with alkynes, unexpectedly reacting faster than unsubstituted phenyl azide and even more faster than unhindered alkyl azide, despite the steric hindrance adjacent to the reactive azido group. Experimental and computational studies have indicated that the steric hindrance eliciting the inhibition of resonance between azido group and the aromatic ring is the primary cause of this apparently-paradoxical phenomenon. This is the first type of steric acceleration, indicating a possibility of designing a highly reactive functional group by strategically locating it in the sterically-congested environment
LACTATE/MCT4/GPR81 AXIS IN BONE PAIN OF BREAST CANCER
Breast cancer (BC) bone metastasis causes bone pain (BP), which detrimentally damages the quality of life and outcome of patients with BC. However, the mechanism of BCâBP is poorly understood, and effective treatments are limited. The present study demonstrated a novel mechanism of BCâBP using a mouse model of bone pain, in which mouse (EO771) and human (MDAâMBâ231) BC cells were injected in the bone marrow cavity of tibiae. Western blot analysis using sensory nerves, in vivo assessment of cancer pain and in vitro calcium flux analysis were performed. These mice developed progressive BCâBP in tibiae in conjunction with an upregulation of phosphorylated pERK1/2 and cAMPâresponse elementâbinding protein (pCREB), which are molecular indicators of neuron excitation, in the dorsal root ganglia (DRG) of sensory nerves. Importantly, mice injected with BC cells, in which the expression of the lactic acid transporter monocarboxylate transporter 4 (MCT4) was silenced, exhibited decreased BCâBP with downregulated expression of pERK1/2 and pCREB in the DRG and reduced circulating levels of lactate compared with mice injected with parental BC cells. Further, silencing of the cellâsurface orphan receptor for lactate, G proteinâcoupled receptor 81 (GPR81), in the F11 sensory neuron cells decreased lactateâpromoted upregulation of pERK1/2 and Ca2+ influx, suggesting that the sensory neuro excitation was inhibited. These results suggested that lactate released from BC cells via MCT4 induced BCâBP through the activation of GPR81 of sensory neurons. In conclusion, the activation of GPR81 of sensory neurons by lactate released via MCT4 from BC was demonstrated to contribute to the induction of BCâBP, and disruption of the interactions among lactate, MCT4 and GPR81 may be a novel approach to control BCâBP
Molecular phylogeny and evolution of alcohol dehydrogenase (Adh) genes in legumes
BACKGROUND: Nuclear genes determine the vast range of phenotypes that are responsible for the adaptive abilities of organisms in nature. Nevertheless, the evolutionary processes that generate the structures and functions of nuclear genes are only now be coming understood. The aim of our study is to isolate the alcohol dehydrogenase (Adh) genes in two distantly related legumes, and use these sequences to examine the molecular evolutionary history of this nuclear gene. RESULTS: We isolated the expressed Adh genes from two species of legumes, Sophora flavescens Ait. and Wisteria floribunda DC., by a RT-PCR based approach and found a new Adh locus in addition to homologues of the Adh genes found previously in legumes. To examine the evolution of these genes, we compared the species and gene trees and found gene duplication of the Adh loci in the legumes occurred as an ancient event. CONCLUSION: This is the first report revealing that some legume species have at least two Adh gene loci belonging to separate clades. Phylogenetic analyses suggest that these genes resulted from relatively ancient duplication events
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