Dragma hippomanicum X: Astragali (Leguminosae) nevadenses novi criticive,singulo peruviano adjecto

One new species,Astragalus tiehmii, and two new varieties,A. convallarius var.margaretae andA. oophorus var.lavinii, are described from Nevada; the relationships of each are discussed and the first is illustrated. Two new combinations,A. eurylobus (Barneby) Barneby andA. serenoi var.shockleyi (M. E. Jones) Barneby are proposed and defended. A new species,A. bryogenes, is described from high Andean Peru (Junín).     

New variety and nomenclatural changes in neotropical Gaultheria (ericaceae)

Gaultheria sclerophylla var.hirsuta Luteyn from Ecuador is described, illustrated, and discussed, and the following new combinations are validated:Gaultheria buxifolia var.elassantha (A. C. Smith) Luteyn,G. buxifolia var.secunda (E. J. Remy) Luteyn,G. lanigera var. rufolanata (Sleumer) Luteyn,G. strigosa var.revoluta (A. C. Smith) Luteyn,G. eriophylla var.mucronata (E. J. Remy) Luteyn,G. alnifolia var.grata (A. C. Smith) Luteyn,G. serrata (Vell. Conc.) Sleumer ex Kinoshita-Gouvêa.     

Taxonomy of Gundlachia (Compositae: Astereae)

Gundlachia, a genus of shrubs occurring in the Caribbean islands, is treated as comprising two species, one of which has six varieties. Five new combinations are made: Gundlachia corymbosa var. apiculata (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. compacta (Urb. & Ekman) M. A. Lane, G. corymbosa var. cubana (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. foliosa (Britton & S. F. Blake) M. A. Lane, and G. corymbosa var. ocoana (Urb. & Ekman) M. A. Lane. Gundlachia is probably most closely related to Gymnosperma.     

Saponins and a lignan derivative of Terminalia tropophylla from the Madagascar Dry Forest

A study of an EtOH extract obtained from the roots of the Madagascan plant Terminalia tropophylla H. Perrier (Combretaceae) led to isolation of the oleanane-type triterpenoid saponin 1, the lignan derivative 2, and the two known saponins arjunglucoside I (3) and sericoside (4). The structures of compounds 1 (terminaliaside A) and 2 (4′-O-cinnamoyl cleomiscosin A) were elucidated using 1D and 2D NMR experiments and mass spectrometry. Compound 1 showed antiproliferative activity against the A2780 human ovarian cancer cell line with an IC₅₀ value of 1.2 μM.     

Arceuthobium (Viscaceae) in Mexico and Guatemala: Additions and range extensions

Three new dwarf mistletoes are described:Arceuthobium globosum subsp.grandicaule (Mexico and Guatemala),A. aureum subsp.aureum (Guatemala) andA. aureum subsp.petersonii (Chiapas, Mexico).Arceuthobium guatemalense is recorded for the first time in Mexico. Significant range extensions are recorded forA. abietisreligiosae, A. divaricatum,A. gillii subsp.nigrum, andA. rubrum. New hosts are reported for several taxa. Nineteen members of the genus are presently known from Mexico, and three (possibly four) from Guatemala. Chromosome counts are reported for the first time for 3 taxa.     

New species in Adiantum and Pteris (Pteridaceae) from the Andes

We describe, discuss, and illustrate four new species, one inAdiantum (A. capillatum A. R. Sm. &; Prado, from Ecuador) and three species inPteris (P. lellingeri A. R. Sm. &; Prado, from Bolivia;P. venezuelensis A. R. Sm. &; Prado, from Venezuela; andP. websteri A. R. Sm. &; Prado, from Ecuador, Colombia, and Bolivia).     

Unusual withanolides from aeroponically grown Withania somnifera

In an attempt to maximize production and the structural diversity of plant metabolites, the effect of growing the medicinal plant Withania somnifera under soil-less aeroponic conditions on its ability to produce withaferin A and withanolides was investigated. It resulted in the isolation and characterization of two compounds, 3α-(uracil-1-yl)-2,3-dihydrowithaferin A (1) and 3β-(adenin-9-yl)-2,3-dihydrowithaferin A (2), in addition to 10 known withanolides including 2,3-dihydrowithaferin A-3β-O-sulfate. 3β-O-Butyl-2,3-dihydrowithaferin A (3), presumably an artifact formed from withaferin A during the isolation process was also encountered. Reaction of withaferin A with uracil afforded 1 and its epimer, 3β-(uracil-1-yl)-2,3-dihydrowithaferin A (4). The structures of these compounds were elucidated on the basis of their high resolution mass and NMR spectroscopic data.     

Dragma Hippomanicum. I

Two new species are described,Astragalus schinetorum from central Chile (Coquimbo) andA. ledinghamii from southwestern Iran (Fars); in connection with the latter, a new name (A. koelzii) is substituted for the posterior homonymA. unifoliolatus Sirj. & Rech. f.     

Antioxidative activity of (-)-epigallocatechin-3-(3''-O-methyl)gallate isolated from fresh tea leaf and preliminary results on its biological activity

Antioxidative activity of (-)-epigallocatechin-3-(3'-O-methyl)gallate (catechin e) was examined. Catechin e showed a strong antioxidative activity. A preliminary test using rat cancer cells suggests that catechin e also has a strong cytotoxic activity. Among tested catechins, only catechin e has strong activity for both.     

In silico study of carvone derivatives as potential neuraminidase inhibitors

Recent outbreaks of highly pathogenic influenza strains have highlighted the need to develop new anti-influenza drugs. Here, we report an in silico study of carvone derivatives to analyze their binding modes with neuraminidase (NA) active sites. Two proposed carvone analogues, CV(A) and CV(B), with 36 designed ligands were predicted to inhibit NA (PDB ID: 3TI6) using molecular docking. The design is based on structural resemblance with the commercial inhibitor, oseltamivir (OTV), ligand polarity, and amino acid residues in the NA active sites. Docking simulations revealed that ligand A18 has the lowest energy binding (?G_bind) value of ?8.30 kcal mol^-1, comparable to OTV with ?G_bind of ?8.72 kcal mol^-1. A18 formed seven hydrogen bonds (H-bonds) at residues Arg292, Arg371, Asp151, Trp178, Glu227, and Tyr406, while eight H-bonds were formed by OTV with amino acids Arg118, Arg292, Arg371, Glu119, Asp151, and Arg152. Molecular dynamics (MD) simulation was conducted to compare the stability between ligand A18 and OTV with NA. Our simulation study showed that the A18-NA complex is as stable as the OTV-NA complex during the MD simulation of 50 ns through the analysis of RMSD, RMSF, total energy, hydrogen bonding, and MM/PBSA free energy calculations.     

New species and combinations in neotropical Lecythidaceae

Lecythis barnebyi Mori andCorythophora amapaensis Pires ex Mori & Prance are described and the following new combinations are coined:Lecythis brancoensis (R. Knuth) Mori,L. schwackei (R. Knuth) Mori,L. alutacea (A. C. Smith) Mori,L. lurida (Miers)Mori, L. holcogyne (Sandwith)Mori, L. corrugata Poiteau subsp.rosea (Spruce ex Berg) Mori, andCorythophora labriculata (Eyma) Mori & Prance.     

A taxonomic revision of the Antennaria rosea (Asteraceae: Inuleae: Gnaphaliinae) polyploid complex

TheAntennaria rosea species complex is circumscribed to contain four subspecific taxa. A complete synonymy and key to the subspecies ofA. rosea is presented. The following new combinations are proposed:Antennaria rosea subsp.arida (E. Nels.) R. Bayer,A. rosea subsp. confinis (Greene) R. Bayer, andA. rosea subsp. pulvinata (Greene) R. Bayer. The affinities ofA. rosea to other species ofAntennaria are discussed and a key to separateA. rosea from related polyploid complexes is provided.     

In vitro antiamyloidogenic properties of 1,4-naphthoquinones

The aim of this study is to find out whether several 1,4-naphthoquinones (1,4-NQ) can interact with the amyloidogenic pathway of the amyloid precursor protein processing, particularly targeting at β-secretase (BACE), as well as at β-amyloid peptide (Aβ) aggregation and disaggregating preformed Aβ fibrils. Compounds bearing hydroxyl groups at the quinoid (2) or benzenoid rings (5, 6) as well as some 2- and 3-aryl derivatives (11-15) showed BACE inhibitory activity, without effect on amyloid aggregation or disaggregation. The halogenated compounds 8 and 10 were selective for the inhibition of amyloid aggregation. On the other hand, 1,4-naphthoquinone (1), 6-hydroxy-1,4-naphthoquinone (4) and 2-(3,4-dichlorophenyl)-1,4-naphthoquinone (26) did not show any BACE inhibitory activity but were active on amyloid aggregation and disaggregation preformed Aβ fibrils. Juglone (5-hydroxy-1,4-naphthoquinone (3), and 3-(p-hydroxyphenyl)-5-methoxy-1,4-napththoquinone (19) were active on all the three targets. Therefore, we suggest that 1,4-NQ derivatives, specially 3 and 19, should be explored as possible drug candidates or lead compounds for the development of drugs to prevent amyloid aggregation and neurotoxicity in Alzheimer’s disease.     

Changes in Violaxanthin Deepoxidase Activity and Unsaturation of Thylakoid Membrane Lipids in Indica and Japonica RiceUnder Chill and Strong Light

To explore the differences of sesitivities to chill and strong light in indica and japonica rice (Oryza sativa), the changes in unsaturation of thylakoid membrane lipids and xanthophyll cycle were studied under Chill condition and strong light. The contents of unsaturated fatty acids of thylakoid membrane lipids decreased and that of the saturated ones increased with the time of Chill- and strong lighttreatment, resulting in the reduction of the index of unsaturation of fatty acids (IUFA). The activities of violaxanthin deepoxidase (VDE), a key enzyme of xanthophyll cycle, also reduced. The content of violaxanthin (V) increased, and the contents of antheraxanthin (A) and zeaxanthin (Z) decreased, the ratio of (A+Z)/(A+Z+V) decreased correspondingly. Arrhenius analysis showed that VDE was sensitive to both chill and unsaturation level of thylakoid membrane lipids. Correlation analysis showed that there was distinctly positive relationships between IUFA of thylakoid membrane lipids and the activity of VDE, Fv/Fm, and D1 protein content. Lower IUFA values, less fluidity and stability of thylakoid membrane lipids, lower VDE activity and (A+Z)/(A+Z+V) ratio were found in indica rice cv. Shanyou 63 than in japonica rice cv. 9516 under chill and strong light.     

Dibenzylideneacetone analogues as novel Plasmodium falciparum inhibitors

A series of dibenzylideneacetones (A1-A12) and some of their pyrazolines (B1-B4) were synthesized and evaluated in vitro for blood stage antiplasmodial properties in Plasmodium falciparum culture using SYBR-green-I fluorescence assay. The compound (1E, 4E)-1,5-bis(3,4-dimethoxyphenyl)penta-1,4-dien-3-one (A9) was found to be the most active with IC₅₀ of 1.97 μM against chloroquine-sensitive strain (3D7) and 1.69 μM against chloroquine-resistant field isolate (RKL9). The MTT based cytotoxicity assay on HeLa cell line has confirmed that A9 is selective in its action against malaria parasite (with a therapeutic index of 166). Our results revealed that these compounds exhibited promising antiplasmodial activities which can be further explored as potential leads for the development of cheaper, safe, effective and potent drugs against chloroquine-resistant malarial parasites.     

Antioxidative Activity of (-)-Epigallocatechin-3-(3″-O-methyl)gallate Isolated from Fresh Tea Leaf and Preliminary Results on Its Biological Activity

Antioxidative activity of (-)-epigallocatechin-3-(3″-O-methyl)gallate (catechin e) was examined. Catechin e showed a strong antioxidative activity. A preliminary test using rat cancer cells suggests that catechin e also has a strong cytotoxic activity. Among tested catechins, only catechin e has strong activity for both.     

Synthesis and SAR study of new phenylimidazole-pyrazolo[1,5-c]quinazolines as potent phosphodiesterase 10A inhibitors

A series of phenylimidazole-pyrazolo[1,5-c]quinazolines 1a-q was designed, synthesized and characterised as a novel class of potent phophodiesterase 10A (PDE10A) inhibitors. In this series, 2,9-dimethyl-5-(2-(1-methyl-4-phenyl-1H-imidazol-2-yl)ethyl)pyrazolo[1,5-c]quinazoline (1q) showed the highest affinity for PDE10A enzyme (IC₅₀ = 16 nM).     

Total weak acid concentration and effective dissociation constant of nonvolatile buffers in human plasma.

The strong ion approach provides a quantitative physicochemical method for describing the mechanism for an acid-base disturbance. The approach requires species-specific values for the total concentration of plasma nonvolatile buffers (A(tot)) and the effective dissociation constant for plasma nonvolatile buffers (K(a)), but these values have not been determined for human plasma. Accordingly, the purpose of this study was to calculate accurate A(tot) and K(a) values using data obtained from in vitro strong ion titration and CO(2) tonometry. The calculated values for A(tot) (24.1 mmol/l) and K(a) (1.05 x 10(-7)) were significantly (P < 0.05) different from the experimentally determined values for horse plasma and differed from the empirically assumed values for human plasma (A(tot) = 19.0 meq/l and K(a) = 3.0 x 10(-7)). The derivatives of pH with respect to the three independent variables [strong ion difference (SID), PCO(2), and A(tot)] of the strong ion approach were calculated as follows: dpH/dSID(+) = [1 + 10(pK(a)-pH)](2)/(2.303 x [SPCO(2)10(pH-pK'(1)[1 + 10(pK(a)-pH](2) + A(tot)10(pK(a)-PH]]; dpH/dPCO(2) = S10(-pK'(1)/[2.303[A(tot)10(pH)(10(pH + 10(pK(a))(-2) - SID(+)10(-pH)]], dpH/dA(tot) = -1/[2.303[SPCO(2)10(pH-pK'(1) + SID(+)10(pK(a)-pH)]], where S is solubility of CO(2) in plasma. The derivatives provide a useful method for calculating the effect of independent changes in SID(+), PCO(2), and A(tot) on plasma pH. The calculated values for A(tot) and K(a) should facilitate application of the strong ion approach to acid-base disturbances in humans.     

(Arene)Cl₂Ru(II) complexes with N-coordinated estrogen and androgen isonicotinates: interaction with sex hormone binding globulin and anticancer activity

(Arene)dichloridoruthenium(II) complexes with N-coordinated isonicotinates of androgens (6) and estrogens (9) were prepared and tested for affinity to the estrogen receptor (ERα) and sex hormone binding globulin (SHBG), as well as for cytotoxicity in cancer cells. None of the new complexes bound noticeably to the ER and most of them also bound less strongly to SHBG than the corresponding unmetallated steroids 7. In MTT assays the Ru(p-cymene) complexes 9 of 2-substituted estrones were equally or even more cytotoxic than the metal-free steroids against hormone-dependent (MCF-7 breast and KB-V1 cervix carcinomas) and hormone-independent (518A2 melanoma) cells. The addition of external SHBG to MTT assays lowered the cytotoxicities of the complexes 9 and distinctly more so those of some steroids 7, probably by the way of sequestration and reduction of the cellular uptake. In the absence of SHBG the estrogen complexes 9 were internalized by 518A2 melanoma cells and ruthenated their DNA as quantified by ICP-OES. They also ruthenated salmon sperm DNA but did not change the topology of plasmid DNA in EMSA experiments. In addition, the Ru(p-cymene) complex of 2-ethoxyestrone (9c) was shown to reduce the motility of 518A2 melanoma cells in a wound-healing assay.