Sphingosine 1-phosphate (S1P) inhibits monocyte–endothelial cell interaction by regulating of RhoA activity

AbstractRecent studies suggest that sphingosine 1-phosphate (S1P) protects against atherosclerosis. We assessed the effects of S1P on monocyte–endothelial interaction in the presence of inflammatory mediators. Pretreatment of THP-1 cells with S1P abolished Phorbol 12 myristate 13-acetate (PMA)-induced THP-1 cell adhesion to human umbilical vein endothelial cells (HUVECs). S1P inhibited PMA-induced activation of RhoA, but not PKCs. S1P activated p190Rho GTPase activation protein (GAP) only in the presence of PMA, suggesting an inhibitory effect of S1P and PMA to suppress RhoA. In conclusion, S1P inhibited monocyte–endothelial interactions by inhibiting RhoA activity which may explain its anti-atherogenic effects

「環境意識」の社会的構築 -世論調査とメディア報道の長期的分析から-

早大学位記番号:新7987早稲田大

Utility of commercial high‐resolution satellite imagery for monitoring general flowering in Sarawak, Borneo

General flowering (GF), irregular synchronous mass flowering of multiple tree species across multiple families, is a unique biological phenomenon of the mixed lowland dipterocarp forest in Southeast Asia. Characterizing the spatial extent and temporal dynamics of GF is essential for an improved understanding of climate–vegetation interactions and the potential climate change impact on this species-rich rainforest. We investigated the utility of newly available high-temporal (daily) and high-spatial (3–4 m) resolution remote sensing by the PlanetScope commercial satellite constellation for detecting flowering trees in a dipterocarp rainforest at Lambir Hills National Park, Sarawak, Malaysia. Our study was focused on the latest GF event known to have occurred in the region in the year 2019. PlanetScope successfully acquired 13 clear-sky or minimally cloud-contaminated scenes over the park during a study period of January 1, 2019 to August 31, 2019 encompassing the 2019 GF event. In situ phenology observations verified that the PlanetScope images detected the flowering crowns of tree species that turned into white or orange. This multitemporal image dataset also captured the flowering peak and species differences. The correlation coefficients between the multitemporal image signatures and in situ phenology observations were moderate to very strong (0.52–0.85). The results indicated that the 2019 GF event was a whole-park phenomenon with the flowering peak in May. This study reports the first successful satellite-based observations of a GF event and suggests the possibility of regional-scale characterization of species-level phenology in the dipterocarp forest, key information for biodiversity conservation in Southeast Asia

Auto-Luminescent Genetically-Encoded Ratiometric Indicator for Real-Time Ca2+ Imaging at the Single Cell Level

Background: Efficient bioluminescence resonance energy transfer (BRET) from a bioluminescent protein to a fluorescent protein with high fluorescent quantum yield has been utilized to enhance luminescence intensity, allowing single-cell imaging in near real time without external light illumination. Methodology/Principal Findings: We applied BRET to develop an autoluminescent Ca2+ indicator, BRAC, which is composed of Ca^[2+]-binding protein, calmodulin, and its target peptide, M13, sandwiched between a yellow fluorescent protein variant, Venus, and an enhanced Renilla luciferase, RLuc8. Adjusting the relative dipole orientation of the luminescent protein's chromophores improved the dynamic range of BRET signal change in BRAC up to 60%, which is the largest dynamic range among BRET-based indicators reported so far. Using BRAC, we demonstrated successful visualization of Ca2+ dynamics at the single-cell level with temporal resolution at 1 Hz. Moreover, BRAC signals were acquired by ratiometric imaging capable of canceling out Ca^[2+]-independent signal drifts due to change in cell shape, focus shift, etc. Conclusions/Significance: The brightness and large dynamic range of BRAC should facilitate high-sensitive Ca2+ imaging not only in single live cells but also in small living subjects

Monoclonal antibody to galactosylceramide: discrimination of structural difference in the ceramide moiety

AbstractA mouse monoclonal antibody (mAb) was developed against monohexaosylceramide. This mAb differentially reacted on thin-layer chromatograms with 3 types of galactosylceramide (GalCer) obtained from bovine brain. Structural analysis of the 3 glycolipids revealed that they consisted of the same galactose and sphingosine but of apparently different fatty acids. Among the 3 GalCers, the mAb reacted with two GalCers which contained α-hydroxy fatty acids, but not with GalCer composed of nonhydroxy fatty acids. These findings suggest not only that the mAb discriminated the fatty acid composition in the ceramide moiety of GalCer, but also that the ceramide structure defines the immunological epitope as it is known to do for the carbohydrate moiety of glycosphingolipid

Antisense RNA transcripts in the blood may be novel diagnostic markers for colorectal cancer

Numerous genetic studies have been conducted regarding the occurrence of colorectal cancer (CRC) and the prognosis using microarrays. However, adequate investigations into the diagnostic application of microarrays have yet to be performed. The simplicity and accuracy of diagnosis and prognosis tracking are important requirements for its processes, and the use of blood cells for diagnosis is considered to be suitable to meet these requirements. The patients involved in the study were 28 preoperative patients with CRC and 6 healthy individuals who served as controls. RNA was extracted from the blood cells of the patients and analyzed using a sense/antisense RNA custom microarray. In the patients with CRC, the expression levels of 20 sense RNA and 20 antisense RNA species were identified as being significantly altered compared with that of the healthy volunteers (P2.0). Cluster analysis of these RNA species revealed that the top 10 antisense RNAs significantly clustered patients with cancer and healthy individuals separately. Patients with stage I or II CRC exhibited significant changes in the expression levels of 33 sense and 39 antisense RNA species, as compared with healthy volunteers (P2.0). Cluster analysis demonstrated that patients with stage I or II CRC and healthy volunteers formed separate clusters only among the top 20 antisense RNA species. A tracking study of expression levels of haloacid dehalogenase‑like hydrolase domain‑containing 1 (HDHD1) antisense RNA was performed and a significant difference was identified between the CRC and healthy groups revealing that the levels at one week and three months following surgical removal of the cancerous tissue, decreased to almost same levels of the healthy individuals. The results of the current study indicate that HDHD1 antisense RNA may serve as a potential biomarker for the prognosis of CRC

Increased production of intestinal immunoglobulins in Syntenin-1-deficient mice

AbstractSyntenin-1 is an intracellular PDZ protein that binds multiple proteins and regulates protein trafficking, cancer metastasis, exosome production, synaptic formation, and IL-5 signaling. However, the functions of Syntenin-1 have not yet been clearly characterized in detail, especially in vivo. In this study, we generated a Syntenin-1 knock out (KO) mouse strain and analyzed the role(s) of Syntenin-1 in IL-5 signaling, because the direct interaction of Syntenin-1 with the cytoplasmic domain of the IL-5 receptor α subunit and the regulation of IL-5 signaling by Syntenin-1 have been reported. Unexpectedly, the number of IL-5-responding cells was normal and the levels of fecal immunoglobulins were rather higher in the Syntenin-1 KO mice. We also found that IgA and IgM production of splenic B cells stimulated in vitro was increased in Syntenin-1 KO mice. In addition, we showed that a distribution of intestinal microbial flora was influenced in Syntenin-1 KO mice. Our data indicate that Syntenin-1 negatively regulates the intestinal immunoglobulin production and has a function to maintain the intestinal homeostasis in vivo. The analysis of Syntenin-1 KO mice may provide novel information on not only mucosal immunity but also other functions of Syntenin-1 such as cancer metastasis and neural development

Nasogastric tube syndrome induced by an indwelling long intestinal tube

The nasogastric tube (NGT) has become a frequently used device to alleviate gastrointestinal symptoms. Nasogastric tube syndrome (NTS) is an uncommon but potentially life-threatening complication of an indwelling NGT. NTS is characterized by acute upper airway obstruction due to bilateral vocal cord paralysis. We report a case of a 76-year-old man with NTS, induced by an indwelling long intestinal tube. He was admitted to our hospital for treatment of sigmoid colon cancer. He underwent sigmoidectomy to release a bowel obstruction, and had a long intestinal tube inserted to decompress the intestinal tract. He presented acute dyspnea following prolonged intestinal intubation, and bronchoscopy showed bilateral vocal cord paralysis. The NGT was removed immediately, and tracheotomy was performed. The patient was finally discharged in a fully recovered state. NTS be considered in patients complaining of acute upper airway obstruction, not only with a NGT inserted but also with a long intestinal tube