University of the Ryukyus
  • Okinawa, Okinawa, Japan
Recent publications
One new furanocembranoid diterpene, 11-hydroxy-Δ ¹²⁽¹³⁾ -pukalide ( 1 ), along with six known secondary metabolites, 11-acetoxy-Δ ¹²⁽¹³⁾ -pukalide ( 2 ), 13α-acetoxypukalide ( 3 ), pukalide ( 4 ), 3α-methoxyfuranocembranoid ( 5 ), Δ ⁹⁽¹⁵⁾ -africanene ( 6 ), and methyl (5′ E )-5-(2′,6′-dimethylocta-5′,7′-dienyl)furan-3-carboxylate ( 7 ) were isolated from the Okinawan soft coral Sinularia sp. Their chemical structures were elucidated based on spectroscopic analysis (FTIR, NMR, and HRESIMS), and the relative stereochemistry of 1 was determined by NOESY experiments and acetylation, which yielded derivative 2 . In addition, compounds 1 and 7 exhibited toxicity in the brine shrimp lethality test. Graphical Abstract
We examined the chemical constitution of the red alga Laurencia saitoi Perestenko, collected from Katsuura, Boso Peninsula, Chiba Prefecture, Japan. This specimen produced a new polyhalogenated acetogenin, named katsuurallene ( 1 ), which structure was determined by the spectral methods, along with known diterpene, deoxyparguerol ( 2 ) and triterpene, thyrsiferol ( 3 ). In this paper we describe the structural elucidation of katsuurallene together with some biological activities.
We describe the case of a male patient with orofaciodigital (OFD) syndrome type XVI with a homozygous variant of TMEM107 (p.Phe106del) and the additional findings of tibial dysplasia, which is a pivotal finding of OFD syndrome type IV. His family history included two fetuses with anencephaly with or without cleft lip/palate and polydactyly with no genetic information. Careful attention should be given to the interpretation of this rare pattern.
Based on laboratory observations, planktonic foraminifers are omnivorous, feeding zooplankton and phytoplankton. Spinose species tend toward greater dependence on zooplankton prey than on phytoplankton prey, while non-spinose species are more adapted to herbivorous diets. However, the trophic activity of planktonic foraminifers in the natural environment and their trophic positions in the marine food web have not yet been fully understood. The trophic position (TP) of two non-spinose species, Neogloboquadrina dutertrei and Pulleniatina obliquiloculata , was determined by differences in the nitrogen isotopic composition between two amino acids (glutamic acid and phenylalanine). Results show that TP values of N. dutertrei were ~ 2.4, indicating dependence on omnivorous (mixed herbivorous and carnivorous) diets, while those of P. obliquiloculata were ~ 2.1, indicating dependence on herbivorous diets. Together with previous laboratory observations, these TP values suggest that N. dutertrei is a detritivore or scavenger, while P. obliquiloculata is generally a herbivore. This trophic niche separation likely allows these two planktonic foraminiferal species to live within a similar depth zone in the open water column and provides a clue for understanding causes of spatial and temporal changes in their relative abundances in living and sediment assemblages.
Bioenergy is a renewable energy source that saves from fossil fuel dependence. Therefore, it is important to increase the efficiency of bioenergy investments to create an environmentally sustainable energy supply. This paper aims to identify economic indicators significant in forecasting the supply of bioenergy. Considering this goal, an integrated evaluation has been performed for 17 developed economies using the Random Forest method and the Fuzzy Decision-Making Trial and Evaluation Laboratory (QROF-DEMATEL) method. The main contribution of this study is conducting analysis by using both quantitative and qualitative data. Additionally, the coherence of the results made with the QROF-DEMATEL method is also verified by implementing a sensitivity analysis. The results of both approaches are quite similar and provide information about the reliability of the findings. This situation demonstrates that for the development of bioenergy investments, firstly, countries' macroeconomic conditions should be improved. Consequently, economic growth and unemployment (weighting results-0.159 and 0.155) should be primarily considered for the bioenergy supply forecast.
A very critical and integral part of the power system is the distribution networks. The final component of the power system, including transmission systems or consumers, is the distribution system (DS). This leads to the highest energy loss that happens. So improving the performance of distribution networks is required not only to provide the reliability of power supply but also to achieve the most economic cost. By optimizing the power flow and simultaneously minimizing the total emission cost and generation cost and taking into account the power losses, these objectives can be achieved. In recent years, heuristic methods are widely employed for solving such complex problems, and The main modern optimization techniques are genetic algorithm(GA). The most important issue in Evolutionary Algorithms is exploration vs. exploitation. Maybe GA is restricted for exploration features, what causes slow convergence and poor robustness Therefore, using the hybridization strategy, the main reason behind this is that such a hybrid approach is expected to create swape between the exploration and exploitation. This work presents performance improvement of a radial distribution networks using a new hybrid optimization technique of Genetic Algorithms (GA) with Equilibrium optimizer (EO) algorithm called Hybrid Genetic Algorithm Equilibrium optimizer (GAEO). It is used for optimum location and size of Renewable Energy Sources (wind energy, photovoltaic, fuel cell) on distribution systems. DG source locations and capacity have strongly influenced the improvement of the distribution network performance by reducing the entire system's power loss, enhancing the voltage profile, reducing fuel costs and emissions of contaminants.
Numerical simulations of thermo-solutal Marangoni convection in a floating half SiGe zone with radiation effects under zero gravity have been carried out. In this system, thermal and solutal Marangoni flows develop along the melt free surface either in the same direction or opposite directions depending on the directions of thermal and solutal gradients. In present model of a half SiGe zone, the ambient temperature is kept constant. Radiation due to heat loss and heat gain is considered as the dominant heat transfer mechanism from the ambience. Transition mode maps, based on concentration distribution with respect to Marangoni ratio (Rσ=MaC/MaT) and ambient temperature (Ta), have been developed to investigate the effect of radiation at unequal or equal (MaC, MaT) values. The maps reveal the main concentration structures and potential transitions at various Ta values. The opposite thermo-solutal Marangoni flows give rise to more complex structures than those of the same-direction flows. Both heat loss and heat gain may alter or destabilize the concentration distribution in the melt. However, to some extent, heat loss in the opposite-direction flow case provides a stabilizing effect on the azimuthal wave pattern at a lower or higher Rσ value.
Microtubule (MT) dynamics are modulated through the coordinated action of various MT-associated proteins (MAPs). However, the regulatory mechanisms underlying MT dynamics remain unclear. We show that the MAP7 family protein Map7D2 stabilizes MTs to control cell motility and neurite outgrowth. Map7D2 directly bound to MTs through its N-terminal half and stabilized MTs in vitro. Map7D2 localized prominently to the centrosome and partially on MTs in mouse N1-E115 neuronal cells, which expresses two of the four MAP7 family members, Map7D2 and Map7D1. Map7D2 loss decreased the resistance to the MT-destabilizing agent nocodazole without affecting acetylated/detyrosinated stable MTs, suggesting that Map7D2 stabilizes MTs via direct binding. In addition, Map7D2 loss increased the rate of random cell migration and neurite outgrowth, presumably by disturbing the balance between MT stabilization and destabilization. Map7D1 exhibited similar subcellular localization and gene knockdown phenotypes to Map7D2. However, in contrast to Map7D2, Map7D1 was required for the maintenance of acetylated stable MTs. Taken together, our data suggest that Map7D2 and Map7D1 facilitate MT stabilization through distinct mechanisms in cell motility and neurite outgrowth.
Background Accurate cup placement during total hip arthroplasty (THA) is difficult because the intraoperative pelvic position changes even in supine patient position. We developed a device known as HipPointer; it corrects pelvic rotation and creates a functional pelvic plane as a reference. The aim of this study was to determine the device placement accuracy and investigate causes of error. Material and methods HipPointer was used for cup placement in 353 hips of 308 patients who underwent direct-anterior-approach THA in supine position. The mean age at surgery and body mass index were 63.9 (17-90) years and 24.9 (16.6-42.0) kg/m², respectively. The mean observation period was 40.5 (12-73) months. To investigate the accuracy of HipPointer, preoperative planning and postoperative cup placement angles relative to the functional pelvic plane were evaluated using a three-dimensional analysis software, and absolute errors were determined. Results The means ± standard deviations of radiographic inclination (RI) and radiographic anteversion (RA) were 40.2 ± 3.0° and 15.8 ± 3.6°, respectively. The absolute errors of RI and RA were 2.2 ± 2.0° and 2.7 ± 2.3°, respectively. The ratio of the cup placement angle for which both RI and RA are ≤10° in the target zone was 99% (350/353 hips), and the ratio of the absolute errors for which both RI and RA are ≤5° was 80.4% (284/353 hips). Conclusions HipPointer is simple in structure, easy to use, and useful for direct-anterior-approach THA in supine position. It provides good cup placement accuracy.
Concentrations of 13 phase-partitioned polycyclic aromatic hydrocarbons (PAHs) in seawater were monitored monthly off Oki Island, Japan, during 2015–2019 to elucidate seasonal variations, main source, and transport pathways of PAHs in the southwestern Sea of Japan. Total PAH (dissolved plus particulate) concentrations in surface seawater at 36°09.0′N, 133°17.3′E (site OK) were in the range 0.49–9.36 ng L⁻¹ (mean 2.77, SD 2.05 ng L⁻¹) with higher levels in summer–autumn, an order of magnitude lower than those in the East China Sea during 2005 and 2009–2011 and about one-third of those recorded in the Sea of Japan in 2008 and 2010. The main sources of dissolved and particulate PAHs were combustion products. Increasing dissolved PAH levels during July–October indicate that the area around southern Oki Island is impacted by PAH-rich summer continental-shelf water transported by the Tsushima Warm Current flowing from the East China Sea.
We herein report a case of common variable immunodeficiency (CVID). Endoscopy with biopsies disclosed duodenal nodularity with villous flattening associated with CVID. CVID-associated enteropathy is briefly discussed.
Background: To explore the possibility that endosymbiotic dinoflagellates (Symbiodiniaceae) are associated with coral calcification rates, we investigated the diversity of symbiotic algae in coral colonies with different calcification rates within massive and branching corals (Porites australiensis and Acropora digitifera). Methods and results: Genotyping symbiotic algae from colonies with different calcification rates revealed that all the colonies of both species harbored mainly Cladocopium (previously clade C of Symbiodinium). The Cladocopium symbionts in P. australiensis were mainly composed of C15 and C15bn, and those in A. digitifera of C50a and C50c. We did not detect clear relationships between symbiont compositions and calcification rates within the two coral species. Conclusions: Our results suggest that different coral calcification rates within species may be attributed to genetic factors of coral hosts themselves and/or within symbiont genotypes.
Background Although clozapine is effective for treatment-resistant schizophrenia (TRS), the rate of clozapine prescription is still low. Although antipsychotic monotherapy is recommended in clinical practice guidelines, the rate of antipsychotic polypharmacy is still high. There is little evidence on whether a clozapine prescription influences changes in the rate of monotherapy and polypharmacy, including antipsychotics and other psychotropics. We therefore hypothesized that the rate of antipsychotic monotherapy in patients with TRS who were prescribed clozapine would be higher than that in patients with schizophrenia who were not prescribed clozapine. Methods We assessed 8306 patients with schizophrenia nationwide from 178 institutions in Japan from 2016 to 2019. We analyzed the psychotropic prescription data at discharge in patients diagnosed with TRS and with no description of TRS (ND-TRS) based on the diagnosis listed in the discharge summary. Results The rate of antipsychotic monotherapy in the TRS with clozapine group (91.3%) was significantly higher than that in the TRS without clozapine group (45.9%; p < 2.0 × 10 -16) and the ND-TRS without clozapine group (54.7%; p < 2.0 × 10 -16). The rate of antipsychotic monotherapy without any other concomitant psychotropics in the TRS with clozapine group (26.5%) was significantly higher than that in the TRS without clozapine group (12.6%; p = 1.1 × 10 -6) and the ND-TRS without clozapine group (17.0%; p = 5.9 × 10 -6). Conclusions Clozapine prescription could be associated with a high rate of antipsychotic monotherapy. Patients will benefit from the correct diagnosis of TRS and thus from proper clozapine prescription.
Objectives: To evaluate the management and outcome of idiopathic retroperitoneal fibrosis (iRPF) in Japan, and to identify its clinical biomarker. Methods: We retrospectively analyzed 129 patients with iRPF treated between January 2008 and May 2018 at 12 university and related hospitals. Patients treated with glucocorticoid were analyzed to identify a predictive biomarker. These patients were classified into three groups according to overall effectiveness (no change: NC, complete response: CR, and partial response groups: PR), and each parameter was compared statistically. Results: Male-female ratio was 5:1, and median age at diagnosis was 69 (33-86) years. Smoking history was reported in 59.6% of the patients. As treatment, 95 patients received glucocorticoid therapy with an overall response rate of 84%. As a result, serum concentration of IgG4 was significantly decreased in NC group compared with the other two groups (56.6 mg/dL vs. 255 mg/dL, 206 mg/dL, p = 0.0059 and 0.0078). ROC analysis was performed between the nonresponder (NC) and responder groups (CR + PR) to identify the cut-off value of serum IgG4 as a predictive marker. As a result, AUC of 0.793 was confirmed. Conclusions: Pre-treatment serum IgG4 concentration may have potential as a predictive biomarker of steroid treatment.
Dystrophinopathy is caused by alterations in DMD . Approximately 1% of patients remain genetically undiagnosed because intronic variations are not detected by standard methods. Here, we combined laboratory and in silico analyses to identify disease-causing genomic variants in genetically undiagnosed patients and determine the regulatory mechanisms underlying abnormal DMD transcript generation. DMD transcripts from 20 genetically undiagnosed dystrophinopathy patients in whom no exon variants were identified, despite dystrophin deficiency on muscle biopsy, were analyzed by transcriptome sequencing. Genome sequencing captured intronic variants and their effects were interpreted using in silico tools. Targeted long-read sequencing was applied in cases with suspected structural genomic abnormalities. Abnormal DMD transcripts were detected in all cases analyzed. Exonization of intronic sequences was observed in 15 cases and exon skipping in one case; 13 single nucleotide variants and three structural rearrangements were identified as causal genomic variations. DMD transcripts were aberrantly spliced and polyadenylated in two cases in which chromosome rearrangements were detected. In one case, DMD transcripts were terminated due to nucleotide repeat expansion. Our combined analysis approach successfully identified pathogenic events. Detection of diseasing-causing mechanisms in DMD transcripts could inform the therapeutic options for patients with dystrophinopathy.
Purpose There is increased recognition of the importance of mangroves worldwide, with efforts being made to sustainably manage these ecosystems for forestry and fishery use. Although successive monitoring of mangrove growth after planting has been conducted in some afforestation stands, measurements of soil environmental changes accompanying plant growth have not been made in most stands. In this study, we observed the interactive relationship between the underground root biomass of mangrove, Rhizophora stylosa, and soil chemical properties at an afforestation stand on Tarawa atoll, Kiribati. Methods We first estimated underground root biomass in the stand. Next, we measured the concentrations of dissolved phosphorus, nitrogen, and other ions (Br⁻, Ca²⁺, K⁺, Na⁺, Cl⁻, and SO4²⁻) in soil pore water, as well as the isotopic ratio of leaf carbon and nitrogen in mangrove patches of different ages. Results Estimated underground root biomass was positively related with phosphate and nitrate concentrations in soil pore water, indicating the formation of a rhizosphere environment. Leaf δ¹⁵N analysis suggested that the discrimination of nitrogen isotopes during nitrification and/or uptake of NH4⁺ and NO3⁻ occurs in accordance with plant growth. Differences in salt stress among the patches were reflected in leaf δ¹³C, suggesting it would be a good indicator of the physiological response of mangrove plants to salinity. Conclusions Our findings revealed the changes that occur on a yearly basis in the chemical properties of mangrove leaves and soil pore water after mangrove plantation. These data help to improve our understanding of environmental succession during the formation of mangrove ecosystems.
The specificity of the relationship between cnidarian hosts and symbiotic dinoflagellates (zooxanthellae) differs among host species. Some cnidarian hosts can establish symbiotic relationship with various types of zooxanthellae, while others exhibit high fidelity to specific symbiont type. It is not known how compatibility or specificity of the relationship is determined. We hypothesized that some cnidarian hosts select symbiont type that leads to highest fitness when the host is flexible with symbiont type and more than one types of symbionts are available. As a first step to study this possibility, compatibility of clonal polyps of Cassiopea sp. with six strains of cultured zooxanthellae and the fitness of the host associated with different types of symbionts were studied. Polyp diameter was measured and the number of asexual buds were calculated as a measure of host fitness. The number of zooxanthellae in host and in asexual buds was also measured as a measure of symbiont fitness. Three strains KB8 (clade A), Y106 (clade A), and K100 (clade B) were compatible with the Cassiopea polyps, while other three strains, Y103 (clade C), K111 (clade D), and K102 (clade F) were incompatible. No clear difference in the fitness was found among the polyps inoculated with compatible and incompatible symbiont strains. In one experiment, a compatible strain Y106 seemed to decrease host fitness, but this should be checked by further studies. This study suggests that feeding regimes and long observation period might be important when fitness of hosts associated with different types of symbionts is investigated.
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859 members
Yoshihide Ogawa
  • Graduate School of Medicine
Kosuke Ito
  • Department of Physics and Earth Sciences
Fuminori Kanaya
  • Department of Orthopaedic Surgery
Kazuki Tsuji
  • Faculty of Agriculture
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1 Senbaru, Nakagami-gun, 903-0213, Okinawa, Okinawa, Japan
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http://www.u-ryukyu.ac.jp/