Postural instability via a loss of intermittent control in elderly and patients with Parkinson's disease: A model-based and data-driven approach.

Postural instability is one of the major symptoms of Parkinson's disease. Here, we assimilated a model of intermittent delay feedback control during quiet standing into postural sway data from healthy young and elderly individuals as well as patients with Parkinson's disease to elucidate the possible mechanisms of instability. Specifically, we estimated the joint probability distribution of a set of parameters in the model using the Bayesian parameter inference such that the model with the inferred parameters can best-fit sway data for each individual.

Two new sesquiterpenes from Artemisia annua L.

Investigation of the dried whole plants of Artemisia annua led to the isolation of two new sesquiterpenes, artemanins A (1) and B (2), along with twenty-nine known compounds. The structures of the new compounds were elucidated by spectroscopic and chemical means.

[Diversity of Secondary Metabolites from Some Medicinal Plants and Cultivated Lichen Mycobionts].

 Studies on the structural determination, biosynthesis, and biological activities of secondary metabolites from natural sources are significant in the field of natural products chemistry. This review focuses on diverse secondary metabolites isolated from medicinal plants and cultivated mycobionts of lichens in our laboratory. Monoterpene-tetrahydroisoquinoline glycosides and alkaloids isolated from Cephaelis acuminata and Alangium lamarckii gave important information on the biosynthesis of ipecac alkaloids.

Postural flexibility during quiet standing in healthy elderly and patients with Parkinson's disease.

Postural instability is one of the predominant symptoms of Parkinson's disease (PD). Despite its significant impact on the deterioration in quality of life in PD patients, mechanistic causes of the instability have not been clarified. Joint inflexibility at ankle and hip joints might be such a major cause, leading to small variability in the center of pressure (CoP) during quiet stance.

Polyprenylated Benzoylphloroglucinols with DNA Polymerase Inhibitory Activity from the Fruits of Garcinia schomburgkiana.

Chemical investigation of the fruits of Garcinia schomburgkiana collected in Vietnam led to the isolation of eight new schomburgkianones, A-H (1-8), four known (9-12) polyprenylated benzoylphloroglucinols, and four known biflavonoids. The structures of these compounds were elucidated by spectroscopic and chemical means. The absolute configuration at C-40 of 1 and 2 was determined by (1)H NMR analyses of their MPA esters.

Alkaloids from the Tuber of Stephania cf. rotunda.

Chemical investigation of the tuber of Stephania cf. rotunda collected in Vietnam led to the isolation of a new stephaoxocane-type alkaloid, stepharotudine (1), twenty -eight known alkaloids, and two known amides. The chemical structures of the isolated compounds were determined by spectroscopic and chemical methods.

Screening of mammalian DNA polymerase and topoisomerase inhibitors from Garcinia mangostana L. and analysis of human cancer cell proliferation and apoptosis.

We purified and identified eight xanthones from mangosteen (Garcinia mangostana L.) and investigated whether these compounds inhibited the activities of mammalian DNA polymerases (Pols) and human DNA topoisomerases (Topos). β-Mangostin was the strongest inhibitor of both mammalian Pols and human Topos among the isolated xanthones, with 50% inhibitory concentration (IC50) values of 6.

Cinnamtannin B-1 Promotes Migration of Mesenchymal Stem Cells and Accelerates Wound Healing in Mice.

Substances that enhance the migration of mesenchymal stem cells to damaged sites have the potential to improve the effectiveness of tissue repair. We previously found that ethanol extracts of Mallotus philippinensis bark promoted migration of mesenchymal stem cells and improved wound healing in a mouse model. We also demonstrated that bark extracts contain cinnamtannin B-1, a flavonoid with in vitro migratory activity against mesenchymal stem cells.

Serotonergic mechanisms are involved in antidepressant-like effects of bisbenzylisoquinolines liensinine and its analogs isolated from the embryo of Nelumbo nucifera Gaertner seeds in mice.

Objectives: We attempted to ascertain if bisbenzylisoquinoline alkaloids, liensinine and isoliensinine from Nelumbo nucifera Gaertner have antidepressant-like effects and compare the effects with those previously obtained by their analogue neferine.

Methods: Using mice, the forced swimming test (FST) was carried out after treatment with liensinine, isoliensinine and neferine.

Key Findings: Liensinine and isoliensinine elicited antidepressant-like effects in mice after the FST.

Universal and individual characteristics of postural sway during quiet standing in healthy young adults.

The time course of the center of pressure (CoP) during human quiet standing, corresponding to body sway, is a stochastic process, influenced by a variety of features of the underlying neuro-musculo-skeletal system, such as postural stability and flexibility. Due to complexity of the process, sway patterns have been characterized in an empirical way by a number of indices, such as sway size and mean sway velocity. Here, we describe a statistical approach with the aim of estimating "universal" indices, namely parameters that are independent of individual body characteristics and thus are not "hidden" by the presence of individual, daily, and circadian variations of sway; in this manner it is possible to characterize the common aspects of sway dynamics across healthy young adults, in the assumption that they might reflect underlying neural control during quiet standing.

Noisy interlimb coordination can be a main cause of freezing of gait in patients with little to no parkinsonism.

Freezing of gait in patients with Parkinson's disease is associated with several factors, including interlimb incoordination and impaired gait cycle regulation. Gait analysis in patients with Parkinson's disease is confounded by parkinsonian symptoms such as rigidity. To understand the mechanisms underlying freezing of gait, we compared gait patterns during straight walking between 9 patients with freezing of gait but little to no parkinsonism (freezing patients) and 11 patients with Parkinson's disease (non-freezing patients).

Three acetophenones from Acronychia pedunculata.

Phytochemical investigation of the leaves and twigs of Acronychia pedunculata has led to the isolation of three new acetophenone monomers 1-3 as well as 1-[2',4'-dihydroxy-3',5'-di-(3″-methyl-2″-butenyl)-6'-methoxy]phenylethanone (4), acronyculatin E (5), a mixture of β-sitosterol and stigmasterol, and sesamin. The structures of these new compounds were elucidated spectroscopically. The inhibitory activities of the isolated acetophenone derivatives against mammalian DNA polymerases and human cancer cell growth were also assessed.

A 14-membered macrolide and isocoumarin derivatives from the cultured lichen mycobionts of Graphis vestitoides.

Spore-derived mycobionts of the crustose lichen Graphis vestitoides collected in Vietnam were cultivated on a malt-yeast extract medium supplemented with 10% sucrose. The investigation of their metabolites resulted in isolation of a novel 14-membered macrolide and a new isocoumarin, together with five known isocoumarin derivatives. Their structures were determined by spectroscopic and chemical means.

Synthesis and pharmacological activity of alkaloids from embryo of lotus, Nelumbo nucifera.

Bisbenzylisoquinoline alkaloid, nelumboferine which was recently isolated from the embryo of Nelumbo nucifera, and stereoisomers of neferine, which is a major alkaloid of the embryo of N. nucifera, were stereoselectively synthesized. Pharmacological activity of nelumboferine, stereoisomers of neferine, liensinine, isoliensinine, and O-methylneferine were evaluated.

Eremophilane-type sesquiterpenes from cultured lichen mycobionts of Sarcographa tricosa.

Spore-derived mycobionts of the crustose lichen Sarcographa tricosa were cultivated on a malt-yeast extract medium supplemented with 10% sucrose. Chemical investigation of the cultivated colonies led to isolation of three eremophilane-type sesquiterpenes, 3-epi-petasol (1), dihydropetasol (2) and sarcographol (3), together with six known eremophilanes and ergosterol peroxide. These structures were elucidated by spectroscopic and chemical methods.

Bisbenzylisoquinoline Alkaloids from Nelumbo nucifera.

From the embryos of the seeds of Nelumbo nucifera, three bisbenzylisoquinoline alkaloids, nelumboferine and nelumborines A and B, were isolated along with four known compounds, neferine, liensinine, isoliensinine and anisic acid. The structures of the new alkaloids were determined mainly by spectroscopic methods.

Phenolic compounds from the cultured mycobionts of Graphis proserpens.

Spore-derived mycobionts of the lichen Graphis proserpens were cultivated on a malt-yeast extract medium supplemented with 10% sucrose and their metabolites were investigated. Isocoumarin derivatives 1-3 and 7-oxo-5,7-dihydrooxepino[4,3,2-de]isochromene derivatives, proserins A-C (4-6), were isolated along with three known isocoumarin derivatives and three benzoic acid derivatives. Their structures were determined by spectroscopic methods.

Structure and biosynthesis of lecanopyrone, a naphtho[1,8-cd]pyran-3-one derivative from cultured lichen mycobionts of Lecanora leprosa.

From the cultures of spore-derived mycobionts of the lichen Lecanora leprosa a novel naphtho[1,8-cd]pyran-3-one derivative, lecanopyrone, was isolated. Its structure was determined by spectroscopic methods. The assembly pattern of acetate units in its biosynthesis was verified using sodium [1-13C]-acetate and sodium [1,2-13C2]-acetate.

Inhibitory effects of docosyl p-coumarate on DNA topoisomerase activity and human cancer cell growth.

We previously found six compounds of alkyl p-coumarates from a composite plant Artemisia annua L., and chemically synthesized these compounds (cis-isomer of C20, C22 and C24, and trans-isomer of C20, C22 and C24 of p-coumarates are compounds 1-6, respectively). This report describes the inhibitory activities of these alkyl p-coumarates against DNA polymerase (pol), DNA topoisomerase (topo), and human cancer cell growth.

Antidepressant-like effects of neferine in the forced swimming test involve the serotonin1A (5-HT1A) receptor in mice.

The effects of neferine, an alkaloid of Nelumbo nucifera Gaertner embryos, on immobility in the forced swimming test, which is used to evaluate antidepressants, were investigated in mice. The administration of neferine from 25 to 100 mg/kg i.p.

Secoiridoid glucosides and unusual recyclized secoiridoid aglycones from Ligustrum vulgare.

Phytochemical investigation of the dried leaves and twigs of Ligustrum vulgare has led to the isolation of the secoiridoid glucosides, (2''R)- and (2''S)-10-hydroxy-2''-methoxyoleuropeins (1 and 2), and the secoiridoid aglycones, ligustrohemiacetals A (3) and B (4). Their structures were elucidated by spectroscopic and chemical means. Enzymatic hydrolysis of 10-hydroxyoleuropein to the analog of ligustrohemiacetals A and B led to the structural revision of jasmolactones.

Synthesis and DNA polymerase alpha and beta inhibitory activity of alkyl p-coumarates and related compounds.

trans- and cis-Icosyl, docosyl, and tetracosyl p-coumarates, constituents of Artemisia annua L., and their structurally-related compounds were synthesized and evaluated for inhibitory activity on DNA polymerases alpha and beta. Among 30 compounds synthesized, octadecyl trans- and cis-p-coumarates and octadecyl p-hydroxyphenylpropiolate showed strong inhibitory activity on DNA polymerases alpha and beta.

Effects of extracts and neferine from the embryo of Nelumbo nucifera seeds on the central nervous system.

The effects of embryos of the seeds of Nelumbo nucifera on the central nervous system were studied in mice. MeOH extracts of embryos of Nelumbo nucifera seeds significantly inhibited locomotor activity in mice. The MeOH extract was successively partitioned between H(2)O and n-hexane, between H(2)O and CHCl(3), and between H(2)O and n-BuOH.