Chem Pharm Bull (Tokyo)
December 2024
A total synthesis of javaberine A was achieved through a lithium amide-mediated intramolecular hydroamination of an N-allyl aminoalkene. The desired hydroamination was accomplished using an excess of i-PrNH with a substoichiometric amount of n-BuLi. Using an excess of both n-BuLi and i-PrNH led to tandem cyclization, however, resulting in the construction of a tricyclic structure through the formation of one C-N and two C-C bonds in a single operation.
View Article and Find Full Text PDFObjective: Senescence is a cellular physiological process involved in cell aging. One factor that increases senescence is oxidative stress, which can be induced by hydrogen peroxide. Active compounds in turmeric (Curcuma longa) are classified as volatile and non-volatile.
View Article and Find Full Text PDFFlavanones, a class of flavonoids, are abundant in fruits, vegetables, and herbs. They are known to have several biological activities, such as anti-inflammatory and anti-cancer activities, but their effects on obesity remain unclear. Obesity is closely associated with adipocyte differentiation and lipid accumulation in adipose tissue.
View Article and Find Full Text PDFHeterotopic ossification (HO) in Achilles tendon often arises due to endochondral ossification during the healing process following trauma. Retinoic acid receptor γ (RARγ) plays a critical role in this phenomenon. This study aims to elucidate the therapeutic effects of CD1530, an RARγ selective agonist, along with the contributing cells, in Achilles tendon healing, utilizing a cell lineage tracing system.
View Article and Find Full Text PDFCilia are essential organelles and variants in genes governing ciliary function result in ciliopathic diseases. The Ciliogenesis and PLANar polarity Effectors (CPLANE) protein complex is essential for ciliogenesis in animals models but remains poorly defined. Notably, all but one subunit of the CPLANE complex have been implicated in human ciliopathy.
View Article and Find Full Text PDFC3-positive reactive astrocytes play a neurotoxic role in various neurodegenerative diseases. However, the mechanisms controlling C3-positive reactive astrocyte induction are largely unknown. We found that the length of the primary cilium, a cellular organelle that receives extracellular signals was increased in C3-positive reactive astrocytes, and the loss or shortening of primary cilium decreased the count of C3-positive reactive astrocytes.
View Article and Find Full Text PDFBackground: Two mangostin compounds, gamma-mangostin and alpha-mangostin, show anticancer properties through the inhibition of cell proliferation and cell migration. Metastatic triple-negative breast cancer (TNBC) cells, including MDA-MB-231, highly express C-X-C chemokine receptor type 4 (CXCR4) to maintain reactive oxygen species (ROS) and cell migration.
Objectives: This study was performed to analyze and compare different modes of action of γ-mangostin and α-mangostin as antimigratory effects targeted on in MDA-MB-231 as a model of TNBC cell.
Topological electronic transition is the very promising strategy for achieving high band degeneracy (N) and for optimizing thermoelectric performance. Herein, this work verifies in p-type MgSb Bi that topological electronic transition could be the key mechanism responsible for elevating the N of valence band edge from 1 to 6, leading to much improved thermoelectric performance. Through comprehensive spectroscopy characterizations and theoretical calculations of electronic structures, the topological electronic transition from trivial semiconductor is unambiguously demonstrated to topological semimetal of MgSb Bi with increasing the Bi content, due to the strong spin-orbit coupling of Bi and the band inversion.
View Article and Find Full Text PDFBackground: The influence of vision on multi-joint control during dynamic tasks in anterior cruciate ligament (ACL) deficient patients is unknown. Thus, the purpose of this study was to establish a new method for quantifying neuromuscular control by focusing on the variability of multi-joint movement under conditions with different visual information and to determine the cutoff for potential biomarkers of injury risk in ACL deficient individuals.
Methods: Twenty-three ACL deficient patients and 23 healthy subjects participated in this study.
Manipulating thermal properties of materials can be interpreted as the control of how vibrations of atoms (known as phonons) scatter in a crystal lattice. Compared to a perfect crystal, crystalline solids with defects are expected to have shorter phonon mean free paths caused by point defect scattering, leading to lower lattice thermal conductivities than those without defects. While this is true in many cases, alloying can increase the phonon mean free path in the Cd-doped AgSnSbSe system to increase the lattice thermal conductivity from 0.
View Article and Find Full Text PDF[Purpose] This study aimed to investigate whether modification of vastus medialis activity can delay the varus thrust. [Participants and Methods] Ten participants (Kellgren-Laurence grades I: n=2, II: n=6, and III: n=2) diagnosed with knee osteoarthritis were enrolled. The intervention involved free walking on a 10-m walkway at any speed after donning a functional electrical stimulation set to contract the vastus medialis before heel contact.
View Article and Find Full Text PDFAlthough attentional focus affects motor performance, whether corticospinal excitability and intracortical modulations differ between focus strategies depending on the exercise patterns remains unclear. In the present study, using single- and paired-pulse transcranial magnetic stimulation and peripheral nerve stimulation, we demonstrated changes in the cortical and spinal excitability under external focus (EF) and internal focus (IF) conditions with dynamic or static exercise. Participants performed the ramp-and-hold contraction task of right index finger abduction against an object (sponge or wood) with both exercises.
View Article and Find Full Text PDFRetinitis pigmentosa (RP) and macular dystrophy (MD) cause severe retinal dysfunction, affecting 1 in 4000 people worldwide. This disease is currently assumed to be intractable, because effective therapeutic methods have not been established, regardless of genetic or sporadic traits. Here, we examined a RP mouse model in which the Prominin-1 (Prom1) gene was deficient and investigated the molecular events occurring at the outset of retinal dysfunction.
View Article and Find Full Text PDFSome of the best thermoelectric (TE) materials to date are also topological insulators (TIs). While many studies have investigated the effects of topologically-protected TI surface states on TE properties, the conditions needed to realize such effects are quite different from typical operating conditions of TE devices for, , power generation and room-temperature Peltier cooling. As a result, it is still unclear what properties of TIs, especially those related to the bulk band structure, are beneficial for TE performance, if any.
View Article and Find Full Text PDFLow-dimensional materials have unique optical, electronic, mechanical, and chemical properties that make them desirable for a wide range of applications. Nano-scaling materials to confine transport in at least one direction is a common method of designing materials with low-dimensional electronic structures. However, bulk materials give rise to low-dimensional electronic structures when bonding is highly anisotropic.
View Article and Find Full Text PDFThermoelectric (TE) cooling is an environment-friendly alternative to vapor compression cooling. New TE materials with high coefficients of performance are needed to further advance this technology. Narrow-gap semiconductors and semimetals have garnered interest for Peltier cooling, yet large-scale computational searches often rely on material descriptors that do not account for bipolar conduction effects.
View Article and Find Full Text PDFAxon pathfinding is an essential step in neuronal network formation. Shootin1a is a clutch-linker molecule that is mechanically involved in axon outgrowth and guidance. It was previously shown that concentration gradients of axon guidance molecule netrin-1 in the extracellular environment elicit asymmetrically localized Pak1 kinase-mediated phosphorylation of shootin1a within axonal growth cones, which is higher on the netrin-1 source side.
View Article and Find Full Text PDFThe skin is a protective interface between the internal organs and environment and functions not only as a physical barrier but also as an immune organ. However, the immune system in the skin is not fully understood. A member of the thermo-sensitive transient receptor potential (TRP) channel family, TRPM4, which acts as a regulatory receptor in immune cells, was recently reported to be expressed in human skin and keratinocytes.
View Article and Find Full Text PDFAdhesion GPCRs (aGPCRs) are a subfamily of GPCRs that are involved in cell adhesion, cell proliferation, and cell migration in various tissues. G protein-coupled receptor proteolytic site (GPS) of aGPCR is required to cleave the extracellular domain autocatalytically, generating two fragments; a N-terminal fragment (NTF) and a C-terminal fragment (CTF) containing seven transmembrane structure. NTF can interact with CTF non-covalently after cleavage, however the physiological significance of the cleavage of aGPCR at GPS, and also the interaction between NTF and CTF have not been fully clarified yet.
View Article and Find Full Text PDFObjective Patients with autoimmune hemolytic anemia (AIHA) are considered to be at an increased risk of thrombosis, and prophylaxis for venous thromboembolism (VTE) is often recommended. However, the occurrence of thrombosis in Asian patients has not been specifically studied. Thrombotic complications and features of Japanese warm AIHA (WAIHA) patients were studied to see if Japanese patients were at an increased risk of thrombosis and should receive prophylaxis for VTE.
View Article and Find Full Text PDFRare-earth chalcogenides ( = La, Pr, Nd, = S, Se, and Te) have been extensively studied as high-temperature thermoelectric (TE) materials owing to their low lattice thermal conductivity (κ) and tunable electron carrier concentration cation vacancies. In this work, we introduce YTe, a rare-earth chalcogenide with a rocksalt-like vacancy-ordered structure, as a promising n-type TE material. We computationally evaluate the transport properties, optimized TE performance, and doping characteristics of YTe.
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