Raf inhibitors target ras spatiotemporal dynamics.

Background: The lateral segregation of Ras proteins into transient plasma membrane nanoclusters is essential for high-fidelity signal transmission by the Ras mitogen-activated protein kinase (MAPK) cascade. In this spatially constrained signaling system, the dynamics of Ras nanocluster assembly and disassembly control MAPK signal output.

Results: We show here that BRaf inhibitors paradoxically activate CRaf and MAPK signaling in Ras transformed cells by profoundly dysregulating Ras nanocluster dynamics.

Membrane mechanisms for signal transduction: the coupling of the meso-scale raft domains to membrane-skeleton-induced compartments and dynamic protein complexes.

Virtually all biological membranes on earth share the basic structure of a two-dimensional liquid. Such universality and peculiarity are comparable to those of the double helical structure of DNA, strongly suggesting the possibility that the fundamental mechanisms for the various functions of the plasma membrane could essentially be understood by a set of simple organizing principles, developed during the course of evolution. As an initial effort toward the development of such understanding, in this review, we present the concept of the cooperative action of the hierarchical three-tiered meso-scale (2-300 nm) domains in the plasma membrane: (1) actin membrane-skeleton-induced compartments (40-300 nm), (2) raft domains (2-20 nm), and (3) dynamic protein complex domains (3-10nm).

Hierarchical mesoscale domain organization of the plasma membrane.

Based on recent single-molecule imaging results in the living cell plasma membrane, we propose a hierarchical architecture of three-tiered mesoscale (2-300nm) domains to represent the fundamental functional organization of the plasma membrane: (i) membrane compartments of 40-300nm in diameter due to the partitioning of the entire plasma membrane by the actin-based membrane skeleton 'fence' and transmembrane protein 'pickets' anchored to the fence; (ii) raft domains (2-20nm); and (iii) dimers/oligomers and greater complexes of membrane-associated proteins (3-10nm). The basic molecular interactions required for the signal transduction function of the plasma membrane can be fundamentally understood and conveniently summarized as the cooperative actions of these mesoscale domains, where thermal fluctuations/movements of molecules and weak cooperativity play crucial roles.

Full characterization of GPCR monomer-dimer dynamic equilibrium by single molecule imaging.

Receptor dimerization is important for many signaling pathways. However, the monomer-dimer equilibrium has never been fully characterized for any receptor with a 2D equilibrium constant as well as association/dissociation rate constants (termed super-quantification). Here, we determined the dynamic equilibrium for the N-formyl peptide receptor (FPR), a chemoattractant G protein-coupled receptor (GPCR), in live cells at 37°C by developing a single fluorescent-molecule imaging method.

Pilocytic astrocytomas in elderly adults.

Pilocytic astrocytomas are classified as WHO grade I gliomas that occur predominantly in children and young adults. Reports of the tumors in elderly adults are extremely rare. We describe two cases of pilocytic astrocytoma in elderly adults, a 68-year-old man and a 71-year-old woman.

A local application of recombinant human fibroblast growth factor 2 for tibial shaft fractures: A randomized, placebo-controlled trial.

Fibroblast growth factor 2 (FGF-2) is a potent mitogen for mesenchymal cells, and a local application of recombinant human FGF-2 (rhFGF-2) in a gelatin hydrogel has been reported to accelerate bone union in our animal studies and preparatory dose-escalation trial on patients with surgical osteotomy. We have performed a randomized, double-blind, placebo-controlled trial in which patients with fresh tibial shaft fractures of transverse or short oblique type were randomly assigned to three groups receiving a single injection of the gelatin hydrogel containing either placebo or 0.8 mg (low-dosage group) or 2.

Cytotoxic 16-beta-[(D-xylopyranosyl)oxy]oxohexadecanyl triterpene glycosides from a Malagasy plant, Physena sessiliflora.

Brine shrimp lethality assay-guided separation of the MeOH extract of leaves of Physena sessiliflora, which is endemic to Madagascar, afforded eight triterpene glycosides, Physenoside S1-4 and 16-beta-[(d-xylopyranosyl)oxy]oxohexadecanyl homologues, Physenoside S5-8. Structural elucidation of these compounds was based on both spectroscopic analyses and chemical properties. Physenoside S7 and S8 have significant cytotoxic activities in the brine shrimp lethality assay.

Cross-linked fluoroalkyl end-capped co-oligomeric nanoparticle-encapsulated fullerenea new approach to the surface modification of traditional organic polymers with fullerene-containing nanoparticles.

Cross-linked fluoroalkyl end-capped co-oligomeric nanoparticle-encapsulated fullerenes, prepared by deprotecting a fluoroalkyl end-capped isocyanatoethyl methacrylate 2-butanone oxime adduct-1-hydroxy-5-adamantylacrylate co-oligomer in the presence of fullerene, were of well-defined size in the nanometer range (28-82 nm) and exhibited good dispersibility in a variety of solvents such as methanol, ethanol, isopropyl alcohol, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, and 1,2-dichloroethane. Transmission electron microscopy images also showed that these nanocomposites were particles with a mean diameter of 45 nm and that the fullerenes were tightly encapsulated into fluorinated nanoparticle cores. In methanol, these fluorinated nanoparticles emitted fluorescence related to the presence of fullerene and were applied in the surface modification of traditional organic polymers such as poly(methyl methacrylate) (PMMA) to effect good oleophobicity imparted by fluorine on the modified film surfaces.

[Studies on the constituents of cucurbitaceous plants].

I have an opportunity to have co-operative studies with Chinese group of Kunming Institute of Botany. Since then, I have investigated the chemical constituents of a number of Chinese plants of Araliaceae, Umbelliferae, Labiatae, Cucurbitaceae and other families. This review describes the structural elucidation of the cucurbitane, oleanane and dammarane glycosides, and their biological activities under the joint studies on cucurbitaceous plants, Bolbostemma, Hemsleya, Siraitia and Neoalsomitra species.

Antitumor agents. 261. 20(S)-protopanaxadiol and 20(s)-protopanaxatriol as antiangiogenic agents and total assignment of (1)H NMR spectra.

Angiogenesis is a critical step in tumor progression and involves several steps including endothelial cell (EC) proliferation, migration, and matrix remodeling. We investigated the antiangiogenic effects of 20( S)-protopanaxadiol ( 1) and 20( S)-protopanaxatriol ( 2), the sapogenins of two major ginseng saponins, in an angiogenesis model of human umbilical vein endothelial cells (HUVECs). These compounds inhibited the proliferative activity of HUVECs in a dose-dependent manner and have potential as anticancer drug candidates.

Preparation and applications of novel fluoroalkyl end-capped acrylic acid oligomers/silica nanocomposites-encapsulated fullerenes.

Fluoroalkyl end-capped acrylic acid oligomers/fullerenes nanocomposites reacted smoothly with tetraethoxysilane (TEOS) and silica nanoparticles under alkaline conditions to give fluoroalkyl end-capped oligomers/silica composites-encapsulated fullerenes. Interestingly, these isolated fluorinated composites were found to afford nanometer size-controlled colloidal particles with a good dispersibility in a variety of organic solvents including water. More interestingly, these fluorinated silica nanocomposites-encapsulated fullerenes were applied to a new type of surface modification agent, and these nanocomposites were able to disperse well above the poly(methyl methacrylate) films to exhibit not only surface active property imparted by fluorine but also a unique characteristic related to fullerenes in the nanocomposites on the surface, effectively.

Three-dimensional reconstruction of the membrane skeleton at the plasma membrane interface by electron tomography.

Three-dimensional images of the undercoat structure on the cytoplasmic surface of the upper cell membrane of normal rat kidney fibroblast (NRK) cells and fetal rat skin keratinocytes were reconstructed by electron tomography, with 0.85-nm-thick consecutive sections made approximately 100 nm from the cytoplasmic surface using rapidly frozen, deeply etched, platinum-replicated plasma membranes. The membrane skeleton (MSK) primarily consists of actin filaments and associated proteins.

Phenylpropanoid and phenylethanoid derivatives from Kigelia pinnata DC. fruits.

Further phytochemical investigation of the fruits of Kigelia pinnata DC. has yielded a new phenylpropanoid derivative identified as 6-p-coumaroyl-sucrose (1) together with ten known phenylpropanoid and phenylethanoid derivatives (2-11) and a flavonoid glycoside (12). The structures of the isolated compounds were elucidated using various techniques of NMR and MS spectral analysis.

Validation of the care notebook for measuring physical, mental and life well-being of patients with cancer.

To measure patients' QOL in the daily practice of clinical oncology, we developed and tested the Care Notebook. This instrument has 24 questions expressed in single words or short phrases to make it more acceptable to patients. The Care Notebook, EORTC QLQ-C30 and FACIT-Sp-12 were administered to 249 outpatients with cancer.

Paradigm shift of the plasma membrane concept from the two-dimensional continuum fluid to the partitioned fluid: high-speed single-molecule tracking of membrane molecules.

Recent advancements in single-molecule tracking methods with nanometer-level precision now allow researchers to observe the movement, recruitment, and activation of single molecules in the plasma membrane in living cells. In particular, on the basis of the observations by high-speed single-particle tracking at a frame rate of 40,000 frames s(1), the partitioning of the fluid plasma membrane into submicron compartments throughout the cell membrane and the hop diffusion of virtually all the molecules have been proposed. This could explain why the diffusion coefficients in the plasma membrane are considerably smaller than those in artificial membranes, and why the diffusion coefficient is reduced upon molecular complex formation (oligomerization-induced trapping).

A new iridoid diglycoside from Clerodendrum chinense.

A new iridoid diglucoside, 5-O-beta-glucopyranosyl-harpagide, has been isolated from the aerial part of Clerodendrum chinense together with three known iridoid glucosides and six known cyclohexylethanoids. Their structures have been determined by analyses of spectroscopic data.

Fluorescence imaging for monitoring the colocalization of two single molecules in living cells.

The interaction, binding, and colocalization of two or more molecules in living cells are essential aspects of many biological molecular processes, and single-molecule technologies for investigating these processes in live cells, if successfully developed, would become very powerful tools. Here, we developed simultaneous, dual-color, single fluorescent molecule colocalization imaging, to quantitatively detect the colocalization of two species of individual molecules. We first established a method for spatially correcting the two full images synchronously obtained in two different colors, and then for overlaying them with an accuracy of 13 nm.

Triterpenoidal glycosides from Justicia betonica.

dFrom the aerial portion of Justicia betonica L., four triterpenoidal glycosides (justiciosides A-D) were isolated. Their structures were established through chemical and NMR spectroscopic analyses as olean-12-ene-1beta,3beta,11alpha,28-tetraol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, olean-12-ene-1beta,3beta,11alpha,28-tetraol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, 11alpha-methoxy-olean-12-ene-1beta,3beta,28-triol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, 11alpha-methoxy-olean-12-ene-1beta,3beta,28-triol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, respectively.

Terpenic and phenolic glycosides from leaves of Breynia officinalis HEMSL.

From the leaves of Breynia officinalis, collected on Okinawa Island, six terpenic glucosides and six phenolic glycosides were isolated. Two of the terpenic glucosides were found to be known, and they were identified as turpinionoside B and betulalbuside A. The structures of the remaining terpenic glucosides were elucidated to be megastigmane glucosides, named breyniaionosides A-D, using spectroscopic analyses.

Aliphatic alcohol and iridoid glycosides from Asystasia intrusa.

An aliphatic alcohol glycoside (asystoside) and an iridoid diglucoside (3'-O-beta-D-glucopyranosyl-catalpol) were isolated from the aerial part of Asystasia intrusa along with benzyl beta-D-glucopyranoside, zizybeoside I, (6S,9R)-roseoside, verbascoside, ehrenoside, 6beta-hydroxyantirrhide, angeloside, catalpol, ajugol, 6-deoxycatalpol, and scutellarioside II. The structural elucidations were based on analyses of physical and spectroscopic data.

Phenylethanoid and iridoid glycosides from the Thai medicinal plant, Barleria strigosa.

A phenylethanoid (4-hydroxyphenylethyl 4-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranoside) and an iridoid (10-O-trans-coumaroyl-eranthemoside) were isolated from an entire Barleria strigosa plant together with verbascoside, isoverbascoside, decaffeoylverbascoside, (+)-lyoniresinol 3alpha-O-beta-D-glucoside, apigenin 7-O-alpha-L-rhamnosyl-(1-->6)-O-beta-D-glucoside, 7-O-acetyl-8-epi-loganic acid and (3R)-1-octen-3-ol-3-O-beta-D-xylosyl-(1-->6)-beta-D-glucoside. The structural elucidations were based on analyses of physical and spectroscopic data.

Tricin from a malagasy connaraceous plant with potent antihistaminic activity.

The bioassay-guided separation of a Malagasy plant, Agelaea pentagyna, led to the isolation of a flavonoid, tricin (1), with potent inhibitory activity toward exocytosis from antigen-stimulated rat leukemia basophils (RBL-2H3). The structure-activity relationships among structurally related natural and synthetic flavonoids are also discussed.

Activation of insulin receptors by lagerstroemin.

Lagerstroemin, an ellagitannin isolated from the leaves of Lagerstroemia speciosa (L.) Pers. (Lythraceae), was examined for its biological activities.

Lignan and megastigmane glycosides from Sauropus androgynus.

A lignan diglycoside, (-)-isolariciresinol 3alpha-O-beta-apiofuranosyl-(1-->2)-O-beta-glucopyranoside, and a megastigmane glucoside, sauroposide, were isolated from the aerial part of Sauropus androgynus together with (+)-isolariciresinol 3alpha-O-beta-glucopyranoside, (-)-isolariciresinol 3alpha-O-beta-glucopyranoside, (+)-syringaresinol di-O-beta-glucopyranoside, guanosine and corchoionoside C. The structural elucidations were bases on analyses of physical and spectroscopic data.