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Hook. F. (hook. + f)
Selected AbstractsLeaf dark respiration as a function of canopy position in Nothofagus fusca trees grown at ambient and elevated CO2 partial pressures for 5 yearsFUNCTIONAL ECOLOGY, Issue 4 2001K. L. Griffin Summary 1,Mass-based and area-based rates of respiration, leaf nitrogen content, leaf total protein content, non-structural carbohydrates and leaf mass per unit area (LMA) all decreased with depth in the canopy of Nothofagus fusca (Hook. F.) Oerst. (Red beech) trees grown for 5 years at ambient (36 Pa) or elevated (66 Pa) CO2 partial pressures. 2Elevated CO2 partial pressure had a strong effect on dark respiration, decreasing both mass-based and area-based rates at all canopy positions, but had little or no effect on leaf physical and biochemical properties. 3Leaf sugars, starch, protein, N and LMA were all correlated with respiration rate, and are therefore strong predictors of area-based dark respiration rates. The y axis intercept of regressions of respiration rate on mean leaf N, protein, starch and LMA was lower for plants grown at elevated compared to ambient CO2 partial pressures because of the differential effect of growth at elevated CO2 partial pressure on leaf gas-exchange, chemical and physical characteristics. 4,The lower respiration rates for leaves from trees grown at elevated CO2 partial pressure resulted in a significant increase in the ratio of light-saturated net photosynthesis to respiration, increasing the potential carbon-use efficiency of these leaves. [source] Chemical constituents of the essential oils of Goniothalamus malayanus Hook. f. and Thoms.FLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2002Ibrahim bin Jantan Abstract The chemical composition of the leaf, bark and root oils of Goniothalamus malayanus Hook. f. and Thoms. was examined by capillary GC and GC,MS. The leaf oil was made up mainly of sesquiterpenoids, of which ,-selinene (33.6%) was the dominant component. The other major compounds present were viridiflorol (13.1%), epi -globulol (7.7%), (E)-nerolidol (4.4%) and globulol (3.8%). The bark and root oils, which were qualitatively similar but with some variation in levels of the individual constituents, were also rich in sesquiterpenoids (97% and 95%, respectively), with eudesmols as the most abundant compounds. The bark oil contained a higher amount of ,-eudesmol (32.2%), ,-eudesmol (21.8%) and ,-eudesmol (6.6%) than the root oil. Copyright © 2002 John Wiley & Sons, Ltd. [source] Triptolide functions as a potent angiogenesis inhibitorINTERNATIONAL JOURNAL OF CANCER, Issue 1 2010Ming-Fang He Abstract Triptolide is a key anti-inflammatory compound of the Chinese herbal medicine Tripterygium wilfordii Hook. f. (Celastraceae). It also possesses potent antitumor activity. In this study, we show that triptolide is an angiogenesis inhibitor based on various angiogenesis assays. The IC50 in in vitro assays was 45 nM, which was much lower than the plasma concentrations of triptolide in the rat or human administered with T. wilfordii extracts for treating inflammation. When dosed in vivo, triptolide potently inhibited angiogenesis at 100 nM in Matrigel plug assay. Triptolide at 0.75 mg/kg/day significantly blocked tumor angiogenesis and tumor progression in murine tumorigenesis assay. The underlying mechanism of triptolide correlated with downregulation of proangiogenic Tie2 and VEGFR-2 expression in human umbilical vein endothelial cell by semiquantitative RT-PCR and western blot analysis. Although Tie2 inhibition appeared to be a later event as compared with VEGFR-2, Tie2 overexpression significantly attenuated the inhibitory effect of triptolide on endothelial proliferation and network formation. By contrast, Tie2 knockdown mimicked the inhibitory effect of triptolide on endothelial network formation. Our findings suggest that antitumor action of triptolide is partly via inhibition of tumor angiogenesis by blocking 2 endothelial receptor-mediated signaling pathways, and triptolide can be a promising antiangiogenic agent. [source] Isolation of polymorphic microsatellite markers for Begonia sutherlandii Hook. f.MOLECULAR ECOLOGY RESOURCES, Issue 2 2002M. Hughes Abstract Seven polymorphic microsatellite loci have been characterized for investigating population structure in the patchily distributed herb Begonia sutherlandii. Two loci (BSU3 and BSU4) exhibited population specific null alleles; primer redesign and allele sequencing for one of these loci showed two transition mutations in the original primer site. Two loci exhibited imperfect repeat polymorphisms due to single base pair indels in the flanking region (locus BSU6) and in the microsatellite region itself (BSU7). Transversion mutations were also found in the microsatellite region of locus BSU7. The remaining three loci amplified in all individuals tested and appeared to conform to a simple stepwise mutation pattern. [source] Impatiens quadriloba sp. nov. (Balsaminaceae) from Sichuan, ChinaNORDIC JOURNAL OF BOTANY, Issue 3 2010Yi-Yan Cong Impatiens quadriloba K. M. Liu et Y. L. Xiang sp. nov. collected from the Siguniang Mountains Nature Reserve in northwestern Sichuan, China, is described and illustrated. The seed-coat and pollen morphology of the new species are described and diagnostic morphological characters that distinguish the new species from the related I. falcifer Hook. f. are discussed. [source] Notes on identity of some Indian species of Agapetes (Ericaceae)NORDIC JOURNAL OF BOTANY, Issue 1-2 2008Dipanwita Banik Agapetes variegata (Roxb.) D. Don ex G. Don var. bhareliana Airy Shaw is treated here as a separate species; A. bhareliana (Airy Shaw) D. Banik & M. Sanjappa. Resurrected A. macrantha (Hook.) Hook. f., earlier treated as a variety under A. variegata (Roxb.) D. Don ex G. Don as A. variegata var. macrantha (Hook. f.) Airy Shaw. Two new combinations A. macrantha var. grandiflora (Hook.f.) Q.Banik & M.Sanjappa and A. macrantha var. oblanceolata (Airy Shaw) D. Banik & M. Sanjappa are proposed here. A. macrantha var. macrantha and A. macrantha var. oblanceolata are reported for the first time from India. [source] Chemical constituents and antimicrobial activity of medicinal plants from Ghana: Cassia sieberiana, Haematostaphis barteri, Mitragyna inermis and Pseudocedrela kotschyiPHYTOTHERAPY RESEARCH, Issue 8 2008Alex Asase Abstract The antimicrobial activity of the sequential n -hexane, acetone and 50% aqueous methanol extracts of leaves, stem bark and roots of four species of medicinal plants, Cassia sieberiana DC. (Leguminosae), Haematostaphis barteri Hook. f. (Anacardiaceae), Mitragyna inermis (Willd.) O. Kuntze (Rubiaceae) and Pseudocedrela kotschyi (Schweinf.) Harms (Meliaceae), from Ghana were tested against Bacillus subtilis, Pseudomonas syringae and Cladosporium herbarum using TLC direct-autobiographic methods. Extracts from leaves, stem bark and roots of the four species gave a positive result against at least one test organism. Twelve of the 36 extracts were active against B. subtilis, four extracts were active against P. syringae and six were active against C. herbarum. Preliminary chemical analysis revealed the presence of flavonoids, stilbenes and alkaloids. This is the first report of a stilbene from the Anacardiaceae. Copyright © 2008 John Wiley & Sons, Ltd. [source] A revision of Calvoa Hook. f. (Melastomataceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2001ESTRELA FIGUEIREDO FLS A revision of the genus Calvoa Hook. f. (Melastomataceae) is presented. Principal Component Analyses (PCA) and Cluster Analyses (UPGMA) were performed to elucidate three cases of difficult species delimitation and infraspecific variation, with the following results. (1) The separation between C. crassinoda Hook. f. and C. grandifolia Cogn. was clear in the results obtained with both methods. (2) The group of the West-Central African species Calvoa angolensis A. Fern. & R. Fern., C. calliantha Jacq.-Fél., C. monticola A. Chev., C. pulcherrima Gilg ex Engl., C. sapinii De Wild., C. seretii De Wild., C. sinuata Hook. f. and C. subquinquenervia De Wild, proved difficult to resolve with either analysis, but the Cluster Analysis produced results which are more consistent with the identification of the specimens. (3) Neither of the two analyses supported the recognition of infraspecific categories in Calvoa orientalis Taub. Eighteen species are recognized in the genus. The new species Calvoa Jacques-felixii E. Figueiredo is described and the new combination Calvoa seretii subsp. wildemaniana (Exell) E. Figueiredo is made. Four lectotypes are designated. The conservation status of some taxa is discussed. Six species are considered rare and possibly under threat. [source] Reproductive biology of a mycoheterotrophic species, Burmannia wallichii (Burmanniaceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2000DIANXIANG ZHANG The breeding system of a mycoheterotrophic species, Bumannia wallichii (Miers) Hook. f. (Burmanniaceae), is assessed using field observations, floral anatomy, pollen histochemistry and isozyme electrophoresis. The structure of the flower effectively prevents pollinators from accessing the stamens, and no pollinators were observed visiting natural populations in Hong Kong. The pollen is starch-rich but lipid-poor. Analysis of isozyme variation revealed a small proportion of polymorphic loci, a low level of total heterozygosity (HT= 0.1972), and a very high overall fixation index of populations (FIT= 0.6602). These results strongly suggest that B. wallichii is predominantly self-pollinated. The coefficient of gene differentiation (GST) is low (0.05), although it is suggested that this is due to genetic homogenization of populations consonant with the formation of numerous tiny ,diaspora' seeds that are wind dispersed. [source] Activity of triptolide against human mast cells harboring the kinase domain mutant KITCANCER SCIENCE, Issue 7 2009Yanli Jin Gain-of-function mutations of the receptor tyrosine kinase KIT can cause systemic mastocytosis (SM) and gastrointestinal stromal tumors. Most of the constitutively active KIT can be inhibited by imatinib; D816V KIT cannot. In this study, we investigated the activity of triptolide, a diterpenoid isolated from the Chinese herb Tripterygium wilfordii Hook. f., in cells expressing mutant KIT, including D816V KIT. Imatinib-sensitive HMC-1.1 cells harboring the mutation V560G in the juxtamembrane domain of KIT, imatinib-resistant HMC-1.2 cells harboring both V560G and D816V mutations, and murine P815 cells, were treated with triptolide, and analyzed in terms of growth, apoptosis, and signal transduction. The in vivo antitumor activity was evaluated by using the nude mouse xenograft model. Our results demonstrated that triptolide potently inhibits the growth of both human and murine mast cells harboring not only imatinib-sensitive KIT mutation but also imatinib-resistant D816V KIT. Triptolide markedly inhibited KIT mRNA levels and strikingly reduced the levels of phosphorylated and total Stat3, Akt, and Erk1/2, downstream targets of KIT. Triptolide triggered apoptosis by inducing depolarization of mitochondrial potential and release of cytochrome c, downregulation of Mcl-1 and XIAP. Furthermore, triptolide significantly abrogated the growth of imatinib-resistant HMC-1.2 cell xenografts in nude mice and decreased KIT expression in xenografts. Our data demonstrate that triptolide inhibits imatinib-resistant mast cells harboring D816V KIT. Further investigation of triptolide for treatment of human neoplasms driven by gain-of-function KIT mutations is warranted. (Cancer Sci 2009; 100: 1335,1343) [source] | |||||||||||||